Movement Precision and Amplitude as Separate Factors in the Control of Movement.

ERIC Educational Resources Information Center

Kerr, Robert

The purpose of this study was to assess Welford's dual controlling factor interpretation of Fitts' Law--describing movement time as being a linear function of movement distance (or amplitude) and the required precision of the movement (or target width). Welford's amplification of the theory postulates that two separate processes ought to be…

78 FR 60321 - Biweekly Notice; Applications and Amendments to Facility Operating Licenses and Combined Licenses...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-01

... sample selection. A steam generator tube rupture (SGTR) event is one of the design basis accidents that... in the design basis accident analysis. The proposed change will not cause the consequences of a SGTR... changes to the plant design basis or postulated accidents resulting from potential tube degradation. The...

Illustrated study of the semiholographic nonperturbative framework

NASA Astrophysics Data System (ADS)

Banerjee, Souvik; Gaddam, Nava; Mukhopadhyay, Ayan

2017-03-01

Semiholography has been proposed as an effective nonperturbative framework which can consistently combine perturbative and nonperturbative effects for theories like QCD. It is postulated that the strongly coupled nonperturbative sector has a holographic dual in the form of a classical gravity theory in the large N limit, and the perturbative fields determine the gravitational boundary conditions. In this work, we pursue a fundamental derivation of this framework particularly showing how perturbative physics by itself can determine the holographic dual of the infrared, and also the interactions between the perturbative and the holographic sectors. We firstly demonstrate that the interactions between the two sectors can be constrained through the existence of a conserved local energy-momentum tensor for the full system up to hard-soft coupling constants. As an illustration, we set up a biholographic toy theory where both the UV and IR sectors are strongly coupled and holographic with distinct classical gravity duals. In this construction, the requirement that an appropriate gluing can cure the singularities (geodetic incompleteness) of the respective geometries leads us to determine the parameters of the IR theory and the hard-soft couplings in terms of those of the UV theory. The high energy scale behavior of the hard-soft couplings is state-independent but their runnings turn out to be state-dependent. We discuss how our approach can be adapted to the construction of the semiholographic framework for QCD.

A cognitive dual task affects gait variability in patients suffering from chronic low back pain.

PubMed

Hamacher, Dennis; Hamacher, Daniel; Schega, Lutz

2014-11-01

Chronic pain and gait variability in a dual-task situation are both associated with higher risk of falling. Executive functions regulate (dual-task) gait variability. A possible cause explaining why chronic pain increases risk of falling in an everyday dual-task situation might be that pain interferes with executive functions and results in a diminished dual-task capability with performance decrements on the secondary task. The main goal of this experiment was to evaluate the specific effects of a cognitive dual task on gait variability in chronic low back pain (CLBP) patients. Twelve healthy participants and twelve patients suffering from CLBP were included. The subjects were asked to perform a cognitive single task, a walking single task and a motor-cognitive dual task. Stride variability of trunk movements was calculated. A two-way ANOVA was performed to compare single-task walking with dual-task walking and the single cognitive task performance with the motor-cognitive dual-task performance. We did not find any differences in both of the single-task performances between groups. However, regarding single-task walking and dual-task walking, we observed an interaction effect indicating that low back pain patients show significantly higher gait variability in the dual-task condition as compared to controls. Our data suggest that chronic pain reduces motor-cognitive dual-task performance capability. We postulate that the detrimental effects are caused by central mechanisms where pain interferes with executive functions which, in turn, might contribute to increased risk of falling.

Environmental influences on energy balance-related behaviors: A dual-process view

PubMed Central

Kremers, Stef PJ; de Bruijn, Gert-Jan; Visscher, Tommy LS; van Mechelen, Willem; de Vries, Nanne K; Brug, Johannes

2006-01-01

Background Studies on the impact of the 'obesogenic' environment have often used non-theoretical approaches. In this journal's debate and in other papers authors have argued the necessity of formulating conceptual models for differentiating the causal role of environmental influences on behavior. Discussion The present paper aims to contribute to the debate by presenting a dual-process view on the environment – behavior relationship. This view is conceptualized in the EnRG framework (Environmental Research framework for weight Gain prevention). In the framework, behavior is postulated to be the result of a simultaneous influence of conscious and unconscious processes. Environmental influences are hypothesized to influence behavior both indirectly and directly. The indirect causal mechanism reflects the mediating role of behavior-specific cognitions in the influence of the environment on behavior. A direct influence reflects the automatic, unconscious, influence of the environment on behavior. Specific personal and behavioral factors are postulated to moderate the causal path (i.e., inducing either the automatic or the cognitively mediated environment – behavior relation). In addition, the EnRG framework applies an energy balance-approach, stimulating the integrated study of determinants of diet and physical activity. Conclusion The application of a dual-process view may guide research towards causal mechanisms linking specific environmental features with energy balance-related behaviors in distinct populations. The present paper is hoped to contribute to the evolution of a paradigm that may help to disentangle the role of 'obesogenic' environmental factors. PMID:16700907

Political myths and totalitarianism: an anthropological analysis of their causal interrelationship.

PubMed

Svilicić, Niksa; Maldini, Pero

2014-06-01

This paper discusses the key political, anthropological and socio-cultural functions of political myths in the appearance and functioning of totalitarian regimes. A special emphasis is put on structural elements of the myth (mythemes) and the mythic content (narratives) in the processes of artificial construction of a new society (community) based on the myth-inspired ideological postulates. The paper argues that the establishment of totalitarianism marked a certain anthropological devolution. This devolution, in turn, proceeds through the deconstruction of civil society as an organic social sphere and the artificial construction of a new political community based on ideological postulates and political myths. In support of this assertion, it is first shown how the mythical narratives--transformed into political concepts and programs--were the basis of (re)interpretation of the world, society and individual, and essentially determined the nature and functioning of the totalitarian regimes. Then, the specific political myths are analyzed and compared, as well as their content and origin, and particularly their dual function. It in turn is analyzed in the framework of the classical society-community dichotomy, where the (civil) society is founded socio-politically on the social contract, and the (political) community socio-anthropologically on political myth. In a situation of identity and legitimacy crisis, anomie and the weakening of social cohesion--the characteristic conditions of the great economic and political crisis of the early twentieth century that enabled the emergence of totalitarianism--society as a contracting community does not work. A strong need for meaning (at the individual and societal level) affects the citizens' susceptibility to (political) concepts of (re)constitution of (political) community with which they can identify. Right there, totalitarian movements use the cohesive power of the political myth that replaces the rationally based constitution of society, and becomes a means of ideological mystification and political manipulation. Affecting the mind of the citizens, it moves their feelings and motivations and directs their behavior toward the goals of the totalitarian political power. Recent iterations of totalitarianism (Great-Serbian aggression), with the same tragic consequences, were a warning on the actuality of political myths and the danger of a resurgence of totalitarian tendencies.

Subliminal influence on preferences? A test of evaluative conditioning for brief visual conditioned stimuli using auditory unconditioned stimuli

PubMed Central

2017-01-01

In the field of evaluative conditioning (EC), two opposing theories—propositional single-process theory versus dual-process theory—are currently being discussed in the literature. The present set of experiments test a crucial prediction to adjudicate between these two theories: Dual-process theory postulates that evaluative conditioning can occur without awareness of the contingency between conditioned stimulus (CS) and unconditioned stimulus (US); in contrast, single-process propositional theory postulates that EC requires CS-US contingency awareness. In a set of three studies, we experimentally manipulate contingency awareness by presenting the CSs very briefly, thereby rendering it unlikely to be processed consciously. We address potential issues with previous studies on EC with subliminal or near-threshold CSs that limited their interpretation. Across two experiments, we consistently found an EC effect for CSs presented for 1000 ms and consistently failed to find an EC effect for briefly presented CSs. In a third pre-registered experiment, we again found evidence for an EC effect with CSs presented for 1000 ms, and we found some indication for an EC effect for CSs presented for 20 ms. PMID:28989730

Subliminal influence on preferences? A test of evaluative conditioning for brief visual conditioned stimuli using auditory unconditioned stimuli.

PubMed

Heycke, Tobias; Aust, Frederik; Stahl, Christoph

2017-09-01

In the field of evaluative conditioning (EC), two opposing theories-propositional single-process theory versus dual-process theory-are currently being discussed in the literature. The present set of experiments test a crucial prediction to adjudicate between these two theories: Dual-process theory postulates that evaluative conditioning can occur without awareness of the contingency between conditioned stimulus (CS) and unconditioned stimulus (US); in contrast, single-process propositional theory postulates that EC requires CS-US contingency awareness. In a set of three studies, we experimentally manipulate contingency awareness by presenting the CSs very briefly, thereby rendering it unlikely to be processed consciously. We address potential issues with previous studies on EC with subliminal or near-threshold CSs that limited their interpretation. Across two experiments, we consistently found an EC effect for CSs presented for 1000 ms and consistently failed to find an EC effect for briefly presented CSs. In a third pre-registered experiment, we again found evidence for an EC effect with CSs presented for 1000 ms, and we found some indication for an EC effect for CSs presented for 20 ms.

About Perpetuum Mobile without Emotions

NASA Astrophysics Data System (ADS)

Nikulov, Alexey

2002-11-01

It is noted that old belief in impossibility of any perpetuum mobile is the basis of the great confidence in the second law of thermodynamics. The Carnot's principle, «called with the time of Rudolf Clausius as the second law of thermodynamics», was based on this belief and this belief saved the second law in the beginning of 20 century when absolute randomness of any Brownian motion, perpetual motion experimentally observed, was postulated. It is shown that this postulate is not correct according to quantum mechanics. Moreover experimental evidence of its violation is known. Violation of this postulate means violation of the second law and a possibility of useful perpetuum mobile.

The two pathways to being an (un-)popular narcissist.

PubMed

Küfner, Albrecht C P; Nestler, Steffen; Back, Mitja D

2013-04-01

Narcissism affects social relationships from the very first interactions. The overall positivity of social impressions narcissists evoke is, however, unclear-with previous research reporting positive, negative, or null effects on popularity at short-term acquaintance. Here we postulate a dual-pathway model, which explains the effects of narcissism on (un-)popularity as the result of two opposing behavioral pathways: assertiveness and aggressiveness. In two studies, unacquainted German college students (N = 100; N = 68) met in groups of four to six persons and engaged in group discussions. Afterward, they provided ratings of each other's assertiveness, aggressiveness, and likeability. In Study 2, we additionally videotaped the sessions and assessed participants' actual behavior. Results of both studies confirm our dual-pathway hypothesis: There was a "positive" and a "negative" path from targets' narcissism to being liked or not-dependent upon being seen as assertive or aggressive. Behavioral observations showed that expressive and dominant behaviors mediated the positive path, whereas arrogant and combative behaviors mediated the negative path. Initial (un-)popularity of narcissists at early stages of interpersonal interactions depends on the behavioral pathway that is triggered in the given situational context. © 2012 Wiley Periodicals, Inc.

An Expanded Role for the Dorsal Auditory Pathway in Sensorimotor Control and Integration

PubMed Central

Rauschecker, Josef P.

2010-01-01

The dual-pathway model of auditory cortical processing assumes that two largely segregated processing streams originating in the lateral belt subserve the two main functions of hearing: identification of auditory “objects”, including speech; and localization of sounds in space (Rauschecker and Tian, 2000). Evidence has accumulated, chiefly from work in humans and nonhuman primates, that an antero-ventral pathway supports the former function, whereas a postero-dorsal stream supports the latter, i.e. processing of space and motion-in-space. In addition, the postero-dorsal stream has also been postulated to subserve some functions of speech and language in humans. A recent review (Rauschecker and Scott, 2009) has proposed the possibility that both functions of the postero-dorsal pathway can be subsumed under the same structural forward model: an efference copy sent from prefrontal and premotor cortex provides the basis for “optimal state estimation” in the inferior parietal lobe and in sensory areas of the posterior auditory cortex. The current article corroborates this model by adding and discussing recent evidence. PMID:20850511

The integration of familiarity and recollection information in short-term recognition: modeling speed-accuracy trade-off functions.

PubMed

Göthe, Katrin; Oberauer, Klaus

2008-05-01

Dual process models postulate familiarity and recollection as the basis of the recognition process. We investigated the time-course of integration of the two information sources to one recognition judgment in a working memory task. We tested 24 subjects with a response signal variant of the modified Sternberg recognition task (Oberauer, 2001) to isolate the time course of three different probe types indicating different combinations of familiarity and source information. We compared two mathematical models implementing different ways of integrating familiarity and recollection. Within each model, we tested three assumptions about the nature of the familiarity signal, with familiarity having (a) only positive values, indicating similarity of the probe with the memory list, (b) only negative values, indicating novelty, or (c) both positive and negative values. Both models provided good fits to the data. A model combining the outputs of both processes additively (Integration Model) gave an overall better fit to the data than a model based on a continuous familiarity signal and a probabilistic all-or-none recollection process (Dominance Model).

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

Swamy, S.A.; Bhowmick, D.C.; Prager, D.E.

The regulatory requirements for postulated pipe ruptures have changed significantly since the first nuclear plants were designed. The Leak-Before-Break (LBB) methodology is now accepted as a technically justifiable approach for eliminating postulation of double-ended guillotine breaks (DEGB) in high energy piping systems. The previous pipe rupture design requirements for nuclear power plant applications are responsible for all the numerous and massive pipe whip restraints and jet shields installed for each plant. This results in significant plant congestion, increased labor costs and radiation dosage for normal maintenance and inspection. Also the restraints increase the probability of interference between the piping andmore » supporting structures during plant heatup, thereby potentially impacting overall plant reliability. The LBB approach to eliminate postulating ruptures in high energy piping systems is a significant improvement to former regulatory methodologies, and therefore, the LBB approach to design is gaining worldwide acceptance. However, the methods and criteria for LBB evaluation depend upon the policy of individual country and significant effort continues towards accomplishing uniformity on a global basis. In this paper the historical development of the U.S. LBB criteria will be traced and the results of an LBB evaluation for a typical Japanese PWR primary loop applying U.S. NRC approved methods will be presented. In addition, another approach using the Japanese LBB criteria will be shown and compared with the U.S. criteria. The comparison will be highlighted in this paper with detailed discussion.« less

Gravitational instantons admit hyper-Kähler structure

NASA Astrophysics Data System (ADS)

Aliev, A. N.; Nutku, Y.

1999-01-01

We construct the explicit form of three almost-complex structures that a Riemannian manifold with self-dual curvature admits and show that their Nijenhuis tensors vanish so that they are integrable. This proves that gravitational instantons with self-dual curvature admit hyper-Kähler structure. In order to arrive at the three vector-valued 1-forms defining almost-complex structure, we give a spinor description of real four-dimensional Riemannian manifolds with Euclidean signature in terms of two independent sets of two-component spinors. This is a version of the original Newman-Penrose formalism that is appropriate to the discussion of the mathematical, as well as physical properties of gravitational instantons. We shall build on the work of Goldblatt who first developed an NP formalism for gravitational instantons but we shall adopt it to differential forms in the NP basis to make the formalism much more compact. We shall show that the spin coefficients, connection 1-form, curvature 2-form, Ricci and Bianchi identities, as well as the Maxwell equations naturally split up into their self-dual and anti-self-dual parts corresponding to the two independent spin frames. We shall give the complex dyad as well as the spinor formulation of the almost-complex structures and show that they reappear under the guise of a triad basis for the Petrov classification of gravitational instantons. Completing the work of Salamon on hyper-Kähler structure, we show that the vanishing of the Nijenhuis tensor for all three almost-complex structures depends on the choice of a self-dual gauge for the connection which is guaranteed by virtue of the fact that the curvature 2-form is self-dual for gravitational instantons.

Comparison of two culture approaches, blind passage and dual observation, for detecting Chlamydia trachomatis in various prevalence populations.

PubMed Central

Zimmerman, S J; Moses, E; Sofat, N; Bartholomew, W R; Amsterdam, D

1992-01-01

Chlamydia trachomatis diagnosis in our laboratory consisted of dual inoculation of shell vials and detection of inclusions by using fluorescein-conjugated monoclonal antiserum; the second culture vial was conventionally used for blind passage when the first vial was negative. We compared the increase in positivity using blind passage with that of a strategy utilizing observation of two stained monolayers (dual observation) without blind passage, in an effort to reduce the reporting time and labor associated with the conventional approach. A total of 4,329 specimens were obtained from an obstetrics and gynecology (OB-GYN) clinic (2,563 specimens) and the sexually transmitted disease clinic (1,766 specimens). These specimens were used to compare the two strategies. Blind passage of 1,269 initially culture-negative specimens from the OB-GYN clinic resulted in an additional 6 positive chlamydial diagnoses. In comparison, a similar number of specimens (1,294) from the OB-GYN clinic collected subsequently to the first group were tested by dual observation. There were five additional positive findings. A similar evaluation of specimens from the sexually transmitted disease clinic was performed. Blind passage of 313 initially culture-negative specimens yielded 3 additional positive diagnoses, whereas dual observation of 1,435 similar specimens resulted in 9 positive diagnoses. On the basis of analysis of 4,332 specimens, sensitivity of dual observation is comparable to that of blind passage; labor, cost, and reporting time of dual observation are reduced in comparison to those of blind passage. PMID:1452664

The Feigin Tetrahedron

NASA Astrophysics Data System (ADS)

Rupel, Dylan

2015-03-01

The first goal of this note is to extend the well-known Feigin homomorphisms taking quantum groups to quantum polynomial algebras. More precisely, we define generalized Feigin homomorphisms from a quantum shuffle algebra to quantum polynomial algebras which extend the classical Feigin homomorphisms along the embedding of the quantum group into said quantum shuffle algebra. In a recent work of Berenstein and the author, analogous extensions of Feigin homomorphisms from the dual Hall-Ringel algebra of a valued quiver to quantum polynomial algebras were defined. To relate these constructions, we establish a homomorphism, dubbed the quantum shuffle character, from the dual Hall-Ringel algebra to the quantum shuffle algebra which relates the generalized Feigin homomorphisms. These constructions can be compactly described by a commuting tetrahedron of maps beginning with the quantum group and terminating in a quantum polynomial algebra. The second goal in this project is to better understand the dual canonical basis conjecture for skew-symmetrizable quantum cluster algebras. In the symmetrizable types it is known that dual canonical basis elements need not have positive multiplicative structure constants, while this is still suspected to hold for skew-symmetrizable quantum cluster algebras. We propose an alternate conjecture for the symmetrizable types: the cluster monomials should correspond to irreducible characters of a KLR algebra. Indeed, the main conjecture of this note would establish this ''KLR conjecture'' for acyclic skew-symmetrizable quantum cluster algebras: that is, we conjecture that the images of rigid representations under the quantum shuffle character give irreducible characters for KLR algebras. We sketch a proof in the symmetric case giving an alternative to the proof of Kimura-Qin that all non-initial cluster variables in an acyclic skew-symmetric quantum cluster algebra are contained in the dual canonical basis. With these results in mind we interpret the cluster mutations directly in terms of the representation theory of the KLR algebra.

A comparison of VLSI architecture of finite field multipliers using dual, normal or standard basis

NASA Technical Reports Server (NTRS)

Hsu, I. S.; Truong, T. K.; Shao, H. M.; Deutsch, L. J.; Reed, I. S.

1987-01-01

Three different finite field multipliers are presented: (1) a dual basis multiplier due to Berlekamp; (2) a Massy-Omura normal basis multiplier; and (3) the Scott-Tavares-Peppard standard basis multiplier. These algorithms are chosen because each has its own distinct features which apply most suitably in different areas. Finally, they are implemented on silicon chips with nitride metal oxide semiconductor technology so that the multiplier most desirable for very large scale integration implementations can readily be ascertained.

Imaging and sensing based on dual-pulse nonlinear photoacoustic contrast: a preliminary study on fatty liver

NASA Astrophysics Data System (ADS)

Tian, Chao; Xie, Zhixing; Fabiilli, Mario; Wang, Xueding

2015-03-01

We developed a simple and effective contrast for tissue characterization based on the recently proposed dual-pulse nonlinear photoacoustic technology. The new contrast takes advantage of the temperature dependence of Grüneisen parameter of tissue and involves a dual-pulse laser excitation process. A short pulse first heats the sample and causes a temperature jump, which then leads to the change of Grüneisen parameter and amplitude of the photoacoustic signal of the second pulse. For different tissues, the induced rate or trend of change is expected to be different, which constitutes the basis of the new contrast. Preliminary phantom experiment in blood and lipid mixtures and in vitro experiment in fatty rat liver have demonstrated that the proposed contrast has the capability of fast characterization of lipid-rich and blood-rich tissues.

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

Thomas, Kolle E.; McCormick, Laura J.; Vazquez-Lima, Hugo

Single-crystal X-ray analysis of the β-heptakis(trifluoromethyl)-meso-tetrakis(p-fluorophenyl)porphyrin, H 2[(CF 3) 7T pFPP], has revealed the first example of a stable cis tautomer of a free-base porphyrin, the long-postulated intermediate of porphyrin tautomerism. The stability of the unique molecule appears to reflect a dual origin: a strongly saddled porphyrin skeleton, which alleviates electrostatic repulsion between the two NH protons, and two polarization-enhanced, transannular N−H⋅⋅⋅O−H⋅⋅⋅N hydrogen bond chains, each involving a molecule of water. DFT calculations suggest that the observed tautomer has a lower energy than the alternative, doubly hydrated trans tautomer by some 8.3 kcal mol −1 . A fascinating prospect thusmore » exists that H 2[(CF 3) 7T pFPP]⋅ 2H 2O and cognate structures may act as supramolecular synthons, which, given their chirality, may even be amenable to resolution into optically pure enantiomers.« less

Comparison of the sensitivity and specificity of 5 image sets of dual-energy computed tomography for detecting first-pass myocardial perfusion defects compared with positron emission tomography.

PubMed

Li, Wenhuan; Zhu, Xiaolian; Li, Jing; Peng, Cheng; Chen, Nan; Qi, Zhigang; Yang, Qi; Gao, Yan; Zhao, Yang; Sun, Kai; Li, Kuncheng

2014-12-01

The sensitivity and specificity of 5 different image sets of dual-energy computed tomography (DECT) for the detection of first-pass myocardial perfusion defects have not systematically been compared using positron emission tomography (PET) as a reference standard. Forty-nine consecutive patients, with known or strongly suspected of coronary artery disease, were prospectively enrolled in our study. Cardiac DECT was performed at rest state using a second-generation 128-slice dual-source CT. The DECT data were reconstructed to iodine maps, monoenergetic images, 100 kV images, nonlinearly blended images, and linearly blended images by different postprocessing techniques. The myocardial perfusion defects on DECT images were visually assessed by 5 observers, using standard 17-segment model. Diagnostic accuracy of 5 image sets was assessed using nitrogen-13 ammonia PET as the gold standard. Discrimination was quantified using the area under the receiver operating characteristic curve (AUC), and AUCs were compared using the method of DeLong. The DECT and PET examinations were successfully completed in 30 patients and a total of 90 territories and 510 segments were analyzed. Cardiac PET revealed myocardial perfusion defects in 56 territories (62%) and 209 segments (41%). The AUC of iodine maps, monoenergetic images, 100 kV images, nonlinearly blended images, and linearly blended images were 0.986, 0.934, 0.913, 0.881, and 0.871, respectively, on a per-territory basis. These values were 0.922, 0.813, 0.779, 0.763, and 0.728, respectively, on a per-segment basis. DECT iodine maps shows high sensitivity and specificity, and is superior to other DECT image sets for the detection of myocardial perfusion defects in the first-pass myocardial perfusion.

Diagnostic reasoning: where we've been, where we're going.

PubMed

Monteiro, Sandra M; Norman, Geoffrey

2013-01-01

Recently, clinical diagnostic reasoning has been characterized by "dual processing" models, which postulate a fast, unconscious (System 1) component and a slow, logical, analytical (System 2) component. However, there are a number of variants of this basic model, which may lead to conflicting claims. This paper critically reviews current theories and evidence about the nature of clinical diagnostic reasoning. We begin by briefly discussing the history of research in clinical reasoning. We then focus more specifically on the evidence to support dual-processing models. We conclude by identifying knowledge gaps about clinical reasoning and provide suggestions for future research. In contrast to work on analytical and nonanalytical knowledge as a basis for reasoning, these theories focus on the thinking process, not the nature of the knowledge retrieved. Ironically, this appears to be a revival of an outdated concept. Rather than defining diagnostic performance by problem-solving skills, it is now being defined by processing strategy. The version of dual processing that has received most attention in the literature in medical diagnosis might be labeled a "default/interventionist" model,(17) which suggests that a default system of cognitive processes (System 1) is responsible for cognitive biases that lead to diagnostic errors and that System 2 intervenes to correct these errors. Consequently, from this model, the best strategy for reducing errors is to make students aware of the biases and to encourage them to rely more on System 2. However, an accumulation of evidence suggests that (a) strategies directed at increasing analytical (System 2) processing, by slowing down, reducing distractions, paying conscious attention, and (b) strategies directed at making students aware of the effect of cognitive biases, have no impact on error rates. Conversely, strategies based on increasing application of relevant knowledge appear to have some success and are consistent with basic research on concept formation.

Integrating the behavioral and neural dynamics of response selection in a dual-task paradigm: a dynamic neural field model of Dux et al. (2009).

PubMed

Buss, Aaron T; Wifall, Tim; Hazeltine, Eliot; Spencer, John P

2014-02-01

People are typically slower when executing two tasks than when only performing a single task. These dual-task costs are initially robust but are reduced with practice. Dux et al. (2009) explored the neural basis of dual-task costs and learning using fMRI. Inferior frontal junction (IFJ) showed a larger hemodynamic response on dual-task trials compared with single-task trial early in learning. As dual-task costs were eliminated, dual-task hemodynamics in IFJ reduced to single-task levels. Dux and colleagues concluded that the reduction of dual-task costs is accomplished through increased efficiency of information processing in IFJ. We present a dynamic field theory of response selection that addresses two questions regarding these results. First, what mechanism leads to the reduction of dual-task costs and associated changes in hemodynamics? We show that a simple Hebbian learning mechanism is able to capture the quantitative details of learning at both the behavioral and neural levels. Second, is efficiency isolated to cognitive control areas such as IFJ, or is it also evident in sensory motor areas? To investigate this, we restrict Hebbian learning to different parts of the neural model. None of the restricted learning models showed the same reductions in dual-task costs as the unrestricted learning model, suggesting that efficiency is distributed across cognitive control and sensory motor processing systems.

High-frequency stimulation-induced peptide release synchronizes arcuate kisspeptin neurons and excites GnRH neurons

PubMed Central

Qiu, Jian; Nestor, Casey C; Zhang, Chunguang; Padilla, Stephanie L; Palmiter, Richard D

2016-01-01

Kisspeptin (Kiss1) and neurokinin B (NKB) neurocircuits are essential for pubertal development and fertility. Kisspeptin neurons in the hypothalamic arcuate nucleus (Kiss1ARH) co-express Kiss1, NKB, dynorphin and glutamate and are postulated to provide an episodic, excitatory drive to gonadotropin-releasing hormone 1 (GnRH) neurons, the synaptic mechanisms of which are unknown. We characterized the cellular basis for synchronized Kiss1ARH neuronal activity using optogenetics, whole-cell electrophysiology, molecular pharmacology and single cell RT-PCR in mice. High-frequency photostimulation of Kiss1ARH neurons evoked local release of excitatory (NKB) and inhibitory (dynorphin) neuropeptides, which were found to synchronize the Kiss1ARH neuronal firing. The light-evoked synchronous activity caused robust excitation of GnRH neurons by a synaptic mechanism that also involved glutamatergic input to preoptic Kiss1 neurons from Kiss1ARH neurons. We propose that Kiss1ARH neurons play a dual role of driving episodic secretion of GnRH through the differential release of peptide and amino acid neurotransmitters to coordinate reproductive function. DOI: http://dx.doi.org/10.7554/eLife.16246.001 PMID:27549338

The Development of a Dual-Warhead Impact System for Dynamic Linearity Measurement of a High-g Micro-Electro-Mechanical-Systems (MEMS) Accelerometer

PubMed Central

Shi, Yunbo; Yang, Zhicai; Ma, Zongmin; Cao, Huiliang; Kou, Zhiwei; Zhi, Dan; Chen, Yanxiang; Feng, Hengzhen; Liu, Jun

2016-01-01

Despite its extreme significance, dynamic linearity measurement for high-g accelerometers has not been discussed experimentally in previous research. In this study, we developed a novel method using a dual-warhead Hopkinson bar to measure the dynamic linearity of a high-g acceleration sensor with a laser interference impact experiment. First, we theoretically determined that dynamic linearity is a performance indicator that can be used to assess the quality merits of high-g accelerometers and is the basis of the frequency response. We also found that the dynamic linearity of the dual-warhead Hopkinson bar without an accelerometer is 2.5% experimentally. Further, we verify that dynamic linearity of the accelerometer is 3.88% after calibrating the Hopkinson bar with the accelerometer. The results confirm the reliability and feasibility of measuring dynamic linearity for high-g accelerometers using this method. PMID:27338383

Use of Disjunctive Response Requirements in Dual-Task Environments: Implications for Automation.

DTIC Science & Technology

1986-05-01

could be momentarily held in a short-term sensory buffer for later processing. Broadbent, postulating an early filter model , assumed the physical nature...explicative power of the early filter model , further dichotic listening experiments began to support, as a minimum, a late filter model . Deutsch and Deutsch... filter 63 model came from a study by Cortecn and Wood (1972). Initially, they conditioned a list of city names to electrical shock until the

Self-duality in higher dimensions

NASA Astrophysics Data System (ADS)

Bilge, A. H.; Dereli, T.; Kocak, S.

2017-01-01

Let ω be a 2-form on a 2n dimensional manifold. In previous work, we called ω “strong self-dual, if the eigenvalues of its matrix with respect to an orthonormal frame are equal in absolute value. In a series of papers, we showed that strong self-duality agrees with previous definitions; in particular if ω is strong self-dual, then, in 2n dimensions, ωn is proportional to its Hodge dual ω and in 4n dimensions, ωn is Hodge self-dual. We also obtained a local expression of the Bonan 4-form on 8 manifolds with Spin 7 holonomy, as the sum of the squares of any orthonormal basis of a maximal linear subspace of strong self-dual 2-forms. In the present work we generalize the notion of strong self-duality to odd dimensional manifolds and we express the dual of the Fundamental 3-form 7 manifolds with G 2 holonomy, as a sum of the squares of an orthonormal basis of a maximal linear subspace of strong self-dual 2-forms.

Restriction of virus infection by plants. Final report, July 1, 1987--June 30, 1992

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

Bruening, G.

1992-12-31

The basis of genotypic resistance of the Arlington line of cowpea (Vigna unguiculata) against cowpea mosaic virus (CPMV) has been attributed, to an inhibitor of the processing of CPMV polyproteins. We sought to purify the protein that is postulated to be the inhibitor of polyprotein processing and to characterize the inhibitor and its gene. Such information can be the basis for engineering resistance to specific viruses in plants. In studies with cherry leafroll virus (CLRV) we sought understanding of the biochemical basis of the resistance.

Dual Enrollment as a Liminal Space

ERIC Educational Resources Information Center

Hofmann, Eric; Voloch, Daniel

2012-01-01

Dual enrollment is a place between high school and college that is neither exclusively one nor the other. Dual enrollment inhabits a space where larger questions about higher education--the cultural practices, norms, institutional relationships and interactions, and the overall "business" of learning--are grappled with on a daily basis. To the…

Polarization and propagation characteristics of switchable first-order azimuthally asymmetric beam generated in dual-mode fiber.

PubMed

Khan, Saba N; Chatterjee, Sudip K; Chaudhuri, Partha Roy

2015-02-20

We report here the controlled generation of a linearly polarized first-order azimuthally asymmetric beam (F-AAB) in a dual-mode fiber (DMF) by appropriate superposition of selectively excited zeroth-order vector modes that are doughnut-shaped azimuthally symmetric beams (D-ASBs). We first demonstrate continually switching polarization mode structures having an identical two-lobe intensity profile (i.e., intra-F-AAB conversion). Then, under a distinct launching state, we generate mode structures progressively toggling between the doughnut-shaped profile and two-lobe pattern having dissimilar polarization orientations (i.e., F-AAB to D-ASB conversion). Interestingly, a decentralized elliptical Gaussian beam possessing homogenous spatial polarization is obtained by enhancing the contribution of the fundamental mode (HE₁₁/LP₀₁) in selectively excited F-AAB. A smoothly varying azimuth of the input beam in this situation resulted in redistribution of transverse energy procuring a unique and exciting unconventional two-grain T-polarized beam having mutually orthogonal state of polarization (SOP). All of the above three were achieved under a given set of launching conditions (tilt/offset) of a Gaussian mode (TEM₀₀) devised with changing SOP of the input beam. A strong modulation in the output beam characteristics was also observed with the variation in propagation distance (for a fixed input SOP) owing to the large difference in propagation constants of the participating modes (LP₀₁ and one of the F-AABs). Finally, this particular study led to a design for a low-cost highly sensitive strain measuring device based on tracking the centroid movement of the output intensity pattern. Each of our experimentally observed intensity/polarization distributions is theoretically mapped on a one-to-one basis considering a linear superposition of appropriately excited LP basis modes of the waveguide toward a complete understanding of the polarization and mode propagation in the dual-mode structure.

Self-Calibrating and Remote Programmable Signal Conditioning Amplifier System and Method

NASA Technical Reports Server (NTRS)

Medelius, Pedro J. (Inventor); Hallberg, Carl G. (Inventor); Simpson, Howard J., III (Inventor); Thayer, Stephen W. (Inventor)

1998-01-01

A self-calibrating, remote programmable signal conditioning amplifier system employs information read from a memory attached to a measurement transducer for automatic calibration. The signal conditioning amplifier is self-calibrated on a continuous basis through use of a dual input path arrangement, with each path containing a multiplexer and a programmable amplifier. A digital signal processor controls operation of the system such that a transducer signal is applied to one of the input paths, while one or more calibration signals are applied to the second input path. Once the second path is calibrated, the digital signal processor switches the transducer signal to the second path. and then calibrates the first path. This process is continually repeated so that each path is calibrated on an essentially continuous basis. Dual output paths are also employed which are calibrated in the same manner. The digital signal processor also allows the implementation of a variety of digital filters which are either programmed into the system or downloaded by an operator, and performs up to eighth order linearization.

The numerical study and comparison of radial basis functions in applications of the dual reciprocity boundary element method to convection-diffusion problems

NASA Astrophysics Data System (ADS)

Chanthawara, Krittidej; Kaennakham, Sayan; Toutip, Wattana

2016-02-01

The methodology of Dual Reciprocity Boundary Element Method (DRBEM) is applied to the convection-diffusion problems and investigating its performance is our first objective of the work. Seven types of Radial Basis Functions (RBF); Linear, Thin-plate Spline, Cubic, Compactly Supported, Inverse Multiquadric, Quadratic, and that proposed by [12], were closely investigated in order to numerically compare their effectiveness drawbacks etc. and this is taken as our second objective. A sufficient number of simulations were performed covering as many aspects as possible. Varidated against both exacts and other numerical works, the final results imply strongly that the Thin-Plate Spline and Linear type of RBF are superior to others in terms of both solutions' quality and CPU-time spent while the Inverse Multiquadric seems to poorly yield the results. It is also found that DRBEM can perform relatively well at moderate level of convective force and as anticipated becomes unstable when the problem becomes more convective-dominated, as normally found in all classical mesh-dependence methods.

Stabilization and Structure of the cis  Tautomer of a Free-Base Porphyrin

DOE PAGES

Thomas, Kolle E.; McCormick, Laura J.; Vazquez-Lima, Hugo; ...

2017-03-29

Single-crystal X-ray analysis of the β-heptakis(trifluoromethyl)-meso-tetrakis(p-fluorophenyl)porphyrin, H 2[(CF 3) 7T pFPP], has revealed the first example of a stable cis tautomer of a free-base porphyrin, the long-postulated intermediate of porphyrin tautomerism. The stability of the unique molecule appears to reflect a dual origin: a strongly saddled porphyrin skeleton, which alleviates electrostatic repulsion between the two NH protons, and two polarization-enhanced, transannular N−H⋅⋅⋅O−H⋅⋅⋅N hydrogen bond chains, each involving a molecule of water. DFT calculations suggest that the observed tautomer has a lower energy than the alternative, doubly hydrated trans tautomer by some 8.3 kcal mol −1 . A fascinating prospect thusmore » exists that H 2[(CF 3) 7T pFPP]⋅ 2H 2O and cognate structures may act as supramolecular synthons, which, given their chirality, may even be amenable to resolution into optically pure enantiomers.« less

Implicit and explicit forgetting: when is gist remembered?

PubMed

Dorfman, J; Mandler, G

1994-08-01

Recognition (YES/NO) and stem completion (cued: complete with a word from the list; and uncued: complete with the first word that comes to mind) were tested following either semantic or non-semantic processing of a categorized input list. Item/instance information was tested by contrasting target items from the input list with new items that were categorically related to them; gist/categorical information was tested by comparing target items semantically related to the input items with unrelated new items. For both recognition and stem completion, regardless of initial processing condition, item information decayed rapidly over a period of one week. Gist information was maintained over the same period when initial processing was semantic but only in the cued condition for completion. These results are discussed in terms of dual process theory, which postulates activation/integration of a representation as primarily relevant to implicit item information and elaboration of a representation as mainly relevant to semantic (i.e. categorical) information.

Characterization of NPP Visible/Infrared Imager Radiometer Suite (VIIRS) Reflective Solar Bands Dual Gain Anomaly

NASA Technical Reports Server (NTRS)

Lee, Shihyan; McIntire, Jeff; Oudari, Hassan

2012-01-01

The Visible/Infrared Imager Radiometer Suite (VIIRS) contains six dual gain bands in the reflective solar spectrum. The dual gain bands are designed to switch gain mode at pre-defined thresholds to achieve high resolution at low radiances while maintaining the required dynamic range for science. During pre-launch testing, an anomaly in the electronic response before transitioning from high to low gain was discovered and characterized. On-orbit, the anomaly was confirmed using MODIS data collected during Simultaneous Nadir Overpasses (SNOs). The analysis of the Earth scene data shows that dual gain anomaly can be determined at the orbital basis. To characterize the dual gain anomaly, the anomaly region and electronic offsets were tracked per week during the first 8 month of VIIRS operation. The temporal analysis shows the anomaly region can drift 20 DN and is impacted by detectors DC Restore. The estimated anomaly flagging regions cover 2.5 % of the high gain dynamic range and are consistent with prelaunch and on-orbit LUT. The prelaunch results had a smaller anomaly range (30-50 DN) and are likely the results of more stable electronics from the shorter data collection time. Finally, this study suggests future calibration efforts to focus on the anomaly's impact on science products and possible correction method to reduce uncertainties.

Two intermediate states of the conformational switch in dual specificity phosphatase 13a.

PubMed

Wei, Chun Hwa; Min, Hee Gyeong; Kim, Myeongbin; Kim, Gwan Hee; Chun, Ha-Jung; Ryu, Seong Eon

2018-02-01

Dual specificity phosphatases (DUSPs) include MAP kinase phosphatases and atypical dual specificity phosphatases and mediate cell growth and differentiation, brain function, and immune responses. They serve as targets for drug development against cancers, diabetes and depression. Several DUSPs have non-canonical conformation of the central β-sheet and active site loops, suggesting that they may have conformational switch that is related to the regulation of enzyme activity. Here, we determined the crystal structure of DUSP13a, and identified two different structures that represent intermediates of the postulated conformational switch. Amino acid sequence of DUSP13a is not significantly homologous to DUSPs with conformational switch, indicating that the conformational switch is not sequence-dependent, but rather determined by ligand interaction. The sequence-independency suggests that other DUSPs with canonical conformation may have the conformational switch during specific cellular regulation. The conformational switch leads to significant changes in the protein surface, including a hydrophobic surface and pockets, which can be exploited for development of allosteric modulators of drug target DUSPs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Beyond Inhibition: A Dual-Process Perspective to Renew the Exploration of Binge Drinking

PubMed Central

Lannoy, Séverine; Billieux, Joël; Maurage, Pierre

2014-01-01

Binge drinking is a widespread alcohol-consumption pattern in youth and is linked to cognitive consequences, mostly for executive functions. However, other crucial factors remain less explored in binge drinking and notably the emotional-automatic processes. Dual-process model postulates that addictive disorders are not only due to impaired reflective system (involved in deliberate behaviors), but rather to an imbalance between under-activated reflective system and over-activated affective-automatic one (involved in impulsive behaviors). This proposal has been confirmed in alcohol-dependence, but has not been tested in binge drinking. The observation of comparable impairments in binge drinking and alcohol-dependence led to the “continuum hypothesis,” suggesting similar deficits across different alcohol-related disorders. In this perspective, applying the dual-process model to binge drinking might renew the understanding of this continuum hypothesis. A three-axes research agenda will be proposed, exploring: (1) the affective-automatic system in binge drinking; (2) the systems’ interactions and imbalance in binge drinking; (3) the evolution of this imbalance in the transition between binge drinking and alcohol-dependence. PMID:24926251

A Study of Problems and Responses in the Development of Dual-Language Education Models in Tibetan Regions: Taking Xiahe County in Gannan Tibetan Autonomous Prefecture as an Example

ERIC Educational Resources Information Center

Hongzhi, Long

2017-01-01

Dual-language education models are theoretical and practical systems formed through the process of dual-language education and centered on study and teaching. The language environment is the basis for developing and reforming dual-language education models. The author takes Xiahe County in Gannan Tibetan Autonomous Prefecture as an example and…

Delusional misidentifications and duplications: right brain lesions, left brain delusions.

PubMed

Devinsky, Orrin

2009-01-06

When the delusional misidentification syndromes reduplicative paramnesia and Capgras syndromes result from neurologic disease, lesions are usually bifrontal and/or right hemispheric. The related disorders of confabulation and anosognosis share overlapping mechanisms and anatomic pathology. A dual mechanism is postulated for the delusional misidentification syndromes: negative effects from right hemisphere and frontal lobe dysfunction as well as positive effects from release (i.e., overactivity) of preserved left hemisphere areas. Negative effects of right hemisphere injury impair self-monitoring, ego boundaries, and attaching emotional valence and familiarity to stimuli. The unchecked left hemisphere unleashes a creative narrator from the monitoring of self, memory, and reality by the frontal and right hemisphere areas, leading to excessive and false explanations. Further, the left hemisphere's cognitive style of categorization, often into dual categories, leads it to invent a duplicate or impostor to resolve conflicting information. Delusions result from right hemisphere lesions. But it is the left hemisphere that is deluded.

A technique for measuring vertically and horizontally polarized microwave brightness temperatures using electronic polarization-basis rotation

NASA Technical Reports Server (NTRS)

Gasiewski, Albin J.

1992-01-01

This technique for electronically rotating the polarization basis of an orthogonal-linear polarization radiometer is based on the measurement of the first three feedhorn Stokes parameters, along with the subsequent transformation of this measured Stokes vector into a rotated coordinate frame. The technique requires an accurate measurement of the cross-correlation between the two orthogonal feedhorn modes, for which an innovative polarized calibration load was developed. The experimental portion of this investigation consisted of a proof of concept demonstration of the technique of electronic polarization basis rotation (EPBR) using a ground based 90-GHz dual orthogonal-linear polarization radiometer. Practical calibration algorithms for ground-, aircraft-, and space-based instruments were identified and tested. The theoretical effort consisted of radiative transfer modeling using the planar-stratified numerical model described in Gasiewski and Staelin (1990).

Psychological and Biological Perspectives on Altruism.

ERIC Educational Resources Information Center

Hoffman, Martin L.

1978-01-01

Explores the case for viewing altruism as an inherent part of human nature. Postulates an altruistic disposition or motive to act which is under the control of perceptual and cognitive processes. Presents psychological evidence complementing this view. Discusses social implications of a biological basis for human altruism. (RH)

A Dual-Process Account of the Development of Scientific Reasoning: The Nature and Development of Metacognitive Intercession Skills

ERIC Educational Resources Information Center

Amsel, Eric; Klaczynski, Paul A.; Johnston, Adam; Bench, Shane; Close, Jason; Sadler, Eric; Walker, Rick

2008-01-01

Metacognitive knowledge of the dual-processing basis of judgment is critical to resolving conflict between analytic and experiential processing responses [Klaczynski, P. A. (2004). A dual-process model of adolescent development: Implications for decision making, reasoning, and identity. In R. V. Kail (Ed.), "Advances in child development and…

A Dual System Model of Preferences under Risk

ERIC Educational Resources Information Center

Mukherjee, Kanchan

2010-01-01

This article presents a dual system model (DSM) of decision making under risk and uncertainty according to which the value of a gamble is a combination of the values assigned to it independently by the affective and deliberative systems. On the basis of research on dual process theories and empirical research in Hsee and Rottenstreich (2004) and…

The Neurocognitive Basis for Impaired Dual-Task Performance in Senior Fallers.

PubMed

Nagamatsu, Lindsay S; Hsu, C Liang; Voss, Michelle W; Chan, Alison; Bolandzadeh, Niousha; Handy, Todd C; Graf, Peter; Beattie, B Lynn; Liu-Ambrose, Teresa

2016-01-01

Falls are a major health-care concern, and while dual-task performance is widely recognized as being impaired in those at-risk for falls, the underlying neurocognitive mechanisms remain unknown. A better understanding of the underlying mechanisms could lead to the refinement and development of behavioral, cognitive, or neuropharmacological interventions for falls prevention. Therefore, we conducted a cross-sectional study with community-dwelling older adults aged 70-80 years with a history of falls (i.e., two or more falls in the past 12 months) or no history of falls (i.e., zero falls in the past 12 months); n = 28 per group. We compared functional activation during cognitive-based dual-task performance between fallers and non-fallers using functional magnetic resonance imaging (fMRI). Executive cognitive functioning was assessed via Stroop, Trail Making, and Digit Span. Mobility was assessed via the Timed Up and Go test (TUG). We found that non-fallers exhibited significantly greater functional activation compared with fallers during dual-task performance in key regions responsible for resolving dual-task interference, including precentral, postcentral, and lingual gyri. Further, we report slower reaction times during dual-task performance in fallers and significant correlations between level of functional activation and independent measures of executive cognitive functioning and mobility. Our study is the first neuroimaging study to examine dual-task performance in fallers, and supports the notion that fallers have reduced functional brain activation compared with non-fallers. Given that dual-task performance-and the underlying neural concomitants-appears to be malleable with relevant training, our study serves as a launching point for promising strategies to reduce falls in the future.

Nonviolent unitarization: basic postulates to soft quantum structure of black holes

NASA Astrophysics Data System (ADS)

Giddings, Steven B.

2017-12-01

A first-principles approach to the unitarity problem for black holes is systematically explored, based on the postulates of 1) quantum mechanics 2) the ability to approximately locally divide quantum gravitational systems into subsystems 3) correspondence with quantum field theory predictions for appropriate observers and (optionally) 4) universality of new gravitational effects. Unitarity requires interactions between the internal state of a black hole and its surroundings that have not been identified in the field theory description; correspondence with field theory indicates that these are soft. A conjectured information-theoretic result for information transfer between subsystems, partly motivated by a perturbative argument, then constrains the minimum coupling size of these interactions of the quantum atmosphere of a black hole. While large couplings are potentially astronomically observable, given this conjecture one finds that the new couplings can be exponentially small in the black hole entropy, yet achieve the information transfer rate needed for unitarization, due to the large number of black hole internal states. This provides a new possible alternative to arguments for large effects near the horizon. If universality is assumed, these couplings can be described as small, soft, state-dependent fluctuations of the metric near the black hole. Open questions include that of the more fundamental basis for such an effective picture.

A clinical and experimental overview of sirenomelia: insight into the mechanisms of congenital limb malformations.

PubMed

Garrido-Allepuz, Carlos; Haro, Endika; González-Lamuño, Domingo; Martínez-Frías, María Luisa; Bertocchini, Federica; Ros, Maria A

2011-05-01

Sirenomelia, also known as sirenomelia sequence, is a severe malformation of the lower body characterized by fusion of the legs and a variable combination of visceral abnormalities. The causes of this malformation remain unknown, although the discovery that it can have a genetic basis in mice represents an important step towards the understanding of its pathogenesis. Sirenomelia occurs in mice lacking Cyp26a1, an enzyme that degrades retinoic acid (RA), and in mice that develop with reduced bone morphogenetic protein (Bmp) signaling in the caudal embryonic region. The phenotypes of these mutant mice suggest that sirenomelia in humans is associated with an excess of RA signaling and a deficit in Bmp signaling in the caudal body. Clinical studies of sirenomelia have given rise to two main pathogenic hypotheses. The first hypothesis, based on the aberrant abdominal and umbilical vascular pattern of affected individuals, postulates a primary vascular defect that leaves the caudal part of the embryo hypoperfused. The second hypothesis, based on the overall malformation of the caudal body, postulates a primary defect in the generation of the mesoderm. This review gathers experimental and clinical information on sirenomelia together with the necessary background to understand how deviations from normal development of the caudal part of the embryo might lead to this multisystemic malformation.

Tolerance of an Antarctic Bacterium to Multiple Environmental Stressors.

PubMed

Sengupta, Dipanwita; Sangu, Kavya; Shivaji, Sisinthy; Chattopadhyay, Madhab K

2015-10-01

A population of cold-tolerant Antarctic bacteria was screened for their ability to tolerate other environmental stress factors. Besides low temperature, they were predominantly found to be tolerant to alkali. Attempt was also made to postulate a genetic basis of their multistress-tolerance. Transposon mutagenesis of an isolate Pseudomonas syringae Lz4W was performed, and mutants with delayed growth at low temperature were further screened for sensitivity to some other stress factors. A number of multistress-sensitive mutants were isolated. The mutated gene in one of the mutants sensitive to low temperature, acid and alkali was found to encode citrate synthase. Possible role of citrate synthase in conferring multistress-tolerance was postulated.

Dual host specificity of phage SP6 is facilitated by tailspike rotation

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

Tu, Jiagang

Bacteriophage SP6 exhibits dual-host adsorption specificity. The SP6 tailspikes are recognized as important in host range determination but the mechanisms underlying dual host specificity are unknown. Cryo-electron tomography and sub-tomogram classification were used to analyze the SP6 virion with a particular focus on the interaction of tailspikes with host membranes. The SP6 tail is surrounded by six V-shaped structures that interconnect in forming a hand-over-hand hexameric garland. Each V-shaped structure consists of two trimeric tailspike proteins: gp46 and gp47, connected through the adaptor protein gp37. SP6 infection of Salmonella enterica serovars Typhimurium and Newport results in distinguishable changes in tailspikemore » orientation, providing the first direct demonstration how tailspikes can confer dual host adsorption specificity. SP6 also infects S. Typhimurium strains lacking O antigen; in these infections tailspikes have no apparent specific role and the phage tail must therefore interact with a distinct host receptor to allow infection. - Highlights: •Cryo-electron tomography reveals the structural basis for dual host specificity. •Sub-tomogram classification reveals distinct orientations of the tailspikes during infection of different hosts. •Tailspike-adaptor modules rotate as they bind different O antigens. •In the absence of any O antigen, tailspikes bind weakly and without specificity to LPS. •Interaction of the phage tail with LPS is essential for infection.« less

The Dual System of Vocational Training in Germany. BASIS-INFO 11-1995. Social Policy.

ERIC Educational Resources Information Center

Kraemer, Dagmar

The dual system of vocational training is a joint government-industry program and part of the general educational system in Germany. It provides hands-on training in private businesses coupled with specialized instruction in public vocational schools at no cost to students. The objective of the dual system is to provide young people with the best…

Analysis of sleep on Shuttle missions

NASA Technical Reports Server (NTRS)

Santy, Patricia A.; Kapanka, Heidi; Davis, Jeffrey R.; Stewart, Donald F.

1988-01-01

The sleep patterns of 58 Space Shuttle crew members are analyzed statistically on the basis of debriefing forms filled out within 3 days postflight. The data are compiled in a table, and photographs of typical sleep conditions on the Shuttle are provided. It is found that sleep disruption is relatively common on Shuttle missions, especially on the first and last days. Sleep medication was used by 19.4 percent of crew on single-shift flights and 50 percent of crew on dual-shift flights.

Design and utilisation of protocols to characterise dynamic PET uptake of two tracers using basis pursuit.

PubMed

Bell, Christopher; Puttick, Simon; Rose, Stephen; Smith, Jye; Thomas, Paul; Dowson, Nicholas

2017-06-21

Imaging using more than one biological process using PET could be of great utility, but despite previously proposed approaches to dual-tracer imaging, it is seldom performed. The alternative of performing multiple scans is often infeasible for clinical practice or even in research studies. Dual-tracer PET scanning allows for multiple PET radiotracers to be imaged within the same imaging session. In this paper we describe our approach to utilise the basis pursuit method to aid in the design of dual-tracer PET imaging experiments, and later in separation of the signals. The advantage of this approach is that it does not require a compartment model architecture to be specified or even that both signals are distinguishable in all cases. This means the method for separating dual-tracer signals can be used for many feasible and useful combinations of biology or radiotracer, once an appropriate scanning protocol has been decided upon. Following a demonstration in separating the signals from two consecutively injected radionuclides in a controlled experiment, phantom and list-mode mouse experiments demonstrated the ability to test the feasibility of dual-tracer imaging protocols for multiple injection delays. Increases in variances predicted for kinetic macro-parameters V D and K I in brain and tumoral tissue were obtained when separating the synthetically combined data. These experiments confirmed previous work using other approaches that injections delays of 10-20 min ensured increases in variance were kept minimal for the test tracers used. On this basis, an actual dual-tracer experiment using a 20 min delay was performed using these radio tracers, with the kinetic parameters (V D and K I ) extracted for each tracer in agreement with the literature. This study supports previous work that dual-tracer PET imaging can be accomplished provided certain constraints are adhered to. The utilisation of basis pursuit techniques, with its removed need to specify a model architecture, allows the feasibility of a range of imaging protocols to be investigated via simulation in a straight-forward manner for a wide range of possible scenarios. The hope is that the ease of utilising this approach during feasibility studies and in practice removes any perceived technical barrier to performing dual-tracer imaging.

Design and utilisation of protocols to characterise dynamic PET uptake of two tracers using basis pursuit

NASA Astrophysics Data System (ADS)

Bell, Christopher; Puttick, Simon; Rose, Stephen; Smith, Jye; Thomas, Paul; Dowson, Nicholas

2017-06-01

Imaging using more than one biological process using PET could be of great utility, but despite previously proposed approaches to dual-tracer imaging, it is seldom performed. The alternative of performing multiple scans is often infeasible for clinical practice or even in research studies. Dual-tracer PET scanning allows for multiple PET radiotracers to be imaged within the same imaging session. In this paper we describe our approach to utilise the basis pursuit method to aid in the design of dual-tracer PET imaging experiments, and later in separation of the signals. The advantage of this approach is that it does not require a compartment model architecture to be specified or even that both signals are distinguishable in all cases. This means the method for separating dual-tracer signals can be used for many feasible and useful combinations of biology or radiotracer, once an appropriate scanning protocol has been decided upon. Following a demonstration in separating the signals from two consecutively injected radionuclides in a controlled experiment, phantom and list-mode mouse experiments demonstrated the ability to test the feasibility of dual-tracer imaging protocols for multiple injection delays. Increases in variances predicted for kinetic macro-parameters V D and K I in brain and tumoral tissue were obtained when separating the synthetically combined data. These experiments confirmed previous work using other approaches that injections delays of 10-20 min ensured increases in variance were kept minimal for the test tracers used. On this basis, an actual dual-tracer experiment using a 20 min delay was performed using these radio tracers, with the kinetic parameters (V D and K I) extracted for each tracer in agreement with the literature. This study supports previous work that dual-tracer PET imaging can be accomplished provided certain constraints are adhered to. The utilisation of basis pursuit techniques, with its removed need to specify a model architecture, allows the feasibility of a range of imaging protocols to be investigated via simulation in a straight-forward manner for a wide range of possible scenarios. The hope is that the ease of utilising this approach during feasibility studies and in practice removes any perceived technical barrier to performing dual-tracer imaging.

Dual Sticky Hierarchical Dirichlet Process Hidden Markov Model and Its Application to Natural Language Description of Motions.

PubMed

Hu, Weiming; Tian, Guodong; Kang, Yongxin; Yuan, Chunfeng; Maybank, Stephen

2017-09-25

In this paper, a new nonparametric Bayesian model called the dual sticky hierarchical Dirichlet process hidden Markov model (HDP-HMM) is proposed for mining activities from a collection of time series data such as trajectories. All the time series data are clustered. Each cluster of time series data, corresponding to a motion pattern, is modeled by an HMM. Our model postulates a set of HMMs that share a common set of states (topics in an analogy with topic models for document processing), but have unique transition distributions. For the application to motion trajectory modeling, topics correspond to motion activities. The learnt topics are clustered into atomic activities which are assigned predicates. We propose a Bayesian inference method to decompose a given trajectory into a sequence of atomic activities. On combining the learnt sources and sinks, semantic motion regions, and the learnt sequence of atomic activities, the action represented by the trajectory can be described in natural language in as automatic a way as possible. The effectiveness of our dual sticky HDP-HMM is validated on several trajectory datasets. The effectiveness of the natural language descriptions for motions is demonstrated on the vehicle trajectories extracted from a traffic scene.

Evolution and Distribution of Saxitoxin Biosynthesis in Dinoflagellates

PubMed Central

Orr, Russell J. S.; Stüken, Anke; Murray, Shauna A.; Jakobsen, Kjetill S.

2013-01-01

Numerous species of marine dinoflagellates synthesize the potent environmental neurotoxic alkaloid, saxitoxin, the agent of the human illness, paralytic shellfish poisoning. In addition, certain freshwater species of cyanobacteria also synthesize the same toxic compound, with the biosynthetic pathway and genes responsible being recently reported. Three theories have been postulated to explain the origin of saxitoxin in dinoflagellates: The production of saxitoxin by co-cultured bacteria rather than the dinoflagellates themselves, convergent evolution within both dinoflagellates and bacteria and horizontal gene transfer between dinoflagellates and bacteria. The discovery of cyanobacterial saxitoxin homologs in dinoflagellates has enabled us for the first time to evaluate these theories. Here, we review the distribution of saxitoxin within the dinoflagellates and our knowledge of its genetic basis to determine the likely evolutionary origins of this potent neurotoxin. PMID:23966031

Evolution and distribution of saxitoxin biosynthesis in dinoflagellates.

PubMed

Orr, Russell J S; Stüken, Anke; Murray, Shauna A; Jakobsen, Kjetill S

2013-08-08

Numerous species of marine dinoflagellates synthesize the potent environmental neurotoxic alkaloid, saxitoxin, the agent of the human illness, paralytic shellfish poisoning. In addition, certain freshwater species of cyanobacteria also synthesize the same toxic compound, with the biosynthetic pathway and genes responsible being recently reported. Three theories have been postulated to explain the origin of saxitoxin in dinoflagellates: The production of saxitoxin by co-cultured bacteria rather than the dinoflagellates themselves, convergent evolution within both dinoflagellates and bacteria and horizontal gene transfer between dinoflagellates and bacteria. The discovery of cyanobacterial saxitoxin homologs in dinoflagellates has enabled us for the first time to evaluate these theories. Here, we review the distribution of saxitoxin within the dinoflagellates and our knowledge of its genetic basis to determine the likely evolutionary origins of this potent neurotoxin.

Development and Testing of Operational Dual-Polarimetric Radar Based Lightning Initiation Forecast Techniques

NASA Technical Reports Server (NTRS)

Woodard, Crystal; Carey, Lawrence D.; Petersen, Walter A.; Felix, Mariana; Roeder, William P.

2011-01-01

Lightning is one of Earth s natural dangers, destructive not only to life but also physical property. According to the National Weather Service, there are on average 58 lightning fatalities each year, with over 300 related injuries (NWS 2010). The ability to forecast lightning is critical to a host of activities ranging from space vehicle launch operations to recreational sporting events. For example a single lightning strike to a Space Shuttle could cause billions of dollars of damage and possible loss of life. While forecasting that provides longer lead times could provide sporting officials with more time to respond to possible threatening weather events, thus saving the lives of player and bystanders. Many researchers have developed and tested different methods and tools of first flash forecasting, however few have done so using dual-polarimetric radar variables and products on an operational basis. The purpose of this study is to improve algorithms for the short-term prediction of lightning initiation through development and testing of operational techniques that rely on parameters observed and diagnosed using C-band dual-polarimetric radar.

Unique Characteristics of Diagnostic Classification Models: A Comprehensive Review of the Current State-of-the-Art

ERIC Educational Resources Information Center

Rupp, Andre A.; Templin, Jonathan L.

2008-01-01

"Diagnostic classification models" (DCM) are frequently promoted by psychometricians as important modelling alternatives for analyzing response data in situations where multivariate classifications of respondents are made on the basis of multiple postulated latent skills. In this review paper, a definitional boundary of the space of DCM…

Structural and theoretical basis for ligand exchange on thiolate monolayer protected gold nanoclusters.

PubMed

Heinecke, Christine L; Ni, Thomas W; Malola, Sami; Mäkinen, Ville; Wong, O Andrea; Häkkinen, Hannu; Ackerson, Christopher J

2012-08-15

Ligand exchange reactions are widely used for imparting new functionality on or integrating nanoparticles into devices. Thiolate-for-thiolate ligand exchange in monolayer protected gold nanoclusters has been used for over a decade; however, a firm structural basis of this reaction has been lacking. Herein, we present the first single-crystal X-ray structure of a partially exchanged Au(102)(p-MBA)(40)(p-BBT)(4) (p-MBA = para-mercaptobenzoic acid, p-BBT = para-bromobenzene thiol) with p-BBT as the incoming ligand. The crystal structure shows that 2 of the 22 symmetry-unique p-MBA ligand sites are partially exchanged to p-BBT under the initial fast kinetics in a 5 min timescale exchange reaction. Each of these ligand-binding sites is bonded to a different solvent-exposed Au atom, suggesting an associative mechanism for the initial ligand exchange. Density functional theory calculations modeling both thiol and thiolate incoming ligands postulate a mechanistic pathway for thiol-based ligand exchange. The discrete modification of a small set of ligand binding sites suggests Au(102)(p-MBA)(44) as a powerful platform for surface chemical engineering.

Integrated deterministic and probabilistic safety analysis for safety assessment of nuclear power plants

DOE PAGES

Di Maio, Francesco; Zio, Enrico; Smith, Curtis; ...

2015-07-06

The present special issue contains an overview of the research in the field of Integrated Deterministic and Probabilistic Safety Assessment (IDPSA) of Nuclear Power Plants (NPPs). Traditionally, safety regulation for NPPs design and operation has been based on Deterministic Safety Assessment (DSA) methods to verify criteria that assure plant safety in a number of postulated Design Basis Accident (DBA) scenarios. Referring to such criteria, it is also possible to identify those plant Structures, Systems, and Components (SSCs) and activities that are most important for safety within those postulated scenarios. Then, the design, operation, and maintenance of these “safety-related” SSCs andmore » activities are controlled through regulatory requirements and supported by Probabilistic Safety Assessment (PSA).« less

A Method to Improve Electron Density Measurement of Cone-Beam CT Using Dual Energy Technique

PubMed Central

Men, Kuo; Dai, Jian-Rong; Li, Ming-Hui; Chen, Xin-Yuan; Zhang, Ke; Tian, Yuan; Huang, Peng; Xu, Ying-Jie

2015-01-01

Purpose. To develop a dual energy imaging method to improve the accuracy of electron density measurement with a cone-beam CT (CBCT) device. Materials and Methods. The imaging system is the XVI CBCT system on Elekta Synergy linac. Projection data were acquired with the high and low energy X-ray, respectively, to set up a basis material decomposition model. Virtual phantom simulation and phantoms experiments were carried out for quantitative evaluation of the method. Phantoms were also scanned twice with the high and low energy X-ray, respectively. The data were decomposed into projections of the two basis material coefficients according to the model set up earlier. The two sets of decomposed projections were used to reconstruct CBCT images of the basis material coefficients. Then, the images of electron densities were calculated with these CBCT images. Results. The difference between the calculated and theoretical values was within 2% and the correlation coefficient of them was about 1.0. The dual energy imaging method obtained more accurate electron density values and reduced the beam hardening artifacts obviously. Conclusion. A novel dual energy CBCT imaging method to calculate the electron densities was developed. It can acquire more accurate values and provide a platform potentially for dose calculation. PMID:26346510

A streamlined artificial variable free version of simplex method.

PubMed

Inayatullah, Syed; Touheed, Nasir; Imtiaz, Muhammad

2015-01-01

This paper proposes a streamlined form of simplex method which provides some great benefits over traditional simplex method. For instance, it does not need any kind of artificial variables or artificial constraints; it could start with any feasible or infeasible basis of an LP. This method follows the same pivoting sequence as of simplex phase 1 without showing any explicit description of artificial variables which also makes it space efficient. Later in this paper, a dual version of the new method has also been presented which provides a way to easily implement the phase 1 of traditional dual simplex method. For a problem having an initial basis which is both primal and dual infeasible, our methods provide full freedom to the user, that whether to start with primal artificial free version or dual artificial free version without making any reformulation to the LP structure. Last but not the least, it provides a teaching aid for the teachers who want to teach feasibility achievement as a separate topic before teaching optimality achievement.

A Streamlined Artificial Variable Free Version of Simplex Method

PubMed Central

Inayatullah, Syed; Touheed, Nasir; Imtiaz, Muhammad

2015-01-01

This paper proposes a streamlined form of simplex method which provides some great benefits over traditional simplex method. For instance, it does not need any kind of artificial variables or artificial constraints; it could start with any feasible or infeasible basis of an LP. This method follows the same pivoting sequence as of simplex phase 1 without showing any explicit description of artificial variables which also makes it space efficient. Later in this paper, a dual version of the new method has also been presented which provides a way to easily implement the phase 1 of traditional dual simplex method. For a problem having an initial basis which is both primal and dual infeasible, our methods provide full freedom to the user, that whether to start with primal artificial free version or dual artificial free version without making any reformulation to the LP structure. Last but not the least, it provides a teaching aid for the teachers who want to teach feasibility achievement as a separate topic before teaching optimality achievement. PMID:25767883

Nuclear power and probabilistic safety assessment (PSA): past through future applications

NASA Astrophysics Data System (ADS)

Stamatelatos, M. G.; Moieni, P.; Everline, C. J.

1995-03-01

Nuclear power reactor safety in the United States is about to enter a new era -- an era of risk- based management and risk-based regulation. First, there was the age of `prescribed safety assessment,' during which a series of design-basis accidents in eight categories of severity, or classes, were postulated and analyzed. Toward the end of that era, it was recognized that `Class 9,' or `beyond design basis,' accidents would need special attention because of the potentially severe health and financial consequences of these accidents. The accident at Three Mile Island showed that sequences of low-consequence, high-frequency events and human errors can be much more risk dominant than the Class 9 accidents. A different form of safety assessment, PSA, emerged and began to gain ground against the deterministic safety establishment. Eventually, this led to the current regulatory requirements for individual plant examinations (IPEs). The IPEs can serve as a basis for risk-based regulation and management, a concept that may ultimately transform the U.S. regulatory process from its traditional deterministic foundations to a process predicated upon PSA. Beyond the possibility of a regulatory environment predicated upon PSA lies the possibility of using PSA as the foundation for managing daily nuclear power plant operations.

[Organization and expression of poliovirus genome].

PubMed

Vevcherenko, S G

1984-01-01

In the present paper on the basis of analysis of literary data it is postulated that along with the AUG codon at N743 there exists a second initiation codon in the poliovirus RNA (the AUG codon at N586). The translation initiated at N586 can be transferred to the phase of the major reading frame by removing the small hairpin N732-N744 formed near the first initiation site, or by removing the small region N739-N745. In the first case at the boundary between the hypothetical leader peptide encoded by the 5'-terminus of the long, open reading frame of the spliced poliovirus RNA and the capsid protein VP4 must be the Gln-Gly proteolytic cleavage signal, and in the second case--the Tyr-Gly signal. In both cases the leader peptide can be chipped off by the virus specific proteinase. It is supposed that the exon-intronic structure of the poliovirus genome is needed for coordination of translation and transcription during the poliovirus reproduction cycle.

Dual coil ignition system

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

Huberts, Garlan J.; Qu, Qiuping; Czekala, Michael Damian

2017-03-28

A dual coil ignition system is provided. The dual coil ignition system includes a first inductive ignition coil including a first primary winding and a first secondary winding, and a second inductive ignition coil including a second primary winding and a second secondary winding, the second secondary winding connected in series to the first secondary winding. The dual coil ignition system further includes a diode network including a first diode and a second diode connected between the first secondary winding and the second secondary winding.

Duality and 'particle' democracy

NASA Astrophysics Data System (ADS)

Castellani, Elena

2017-08-01

Weak/strong duality is usually accompanied by what seems a puzzling ontological feature: the fact that under this kind of duality what is viewed as 'elementary' in one description gets mapped to what is viewed as 'composite' in the dual description. This paper investigates the meaning of this apparent 'particle democracy', as it has been called, by adopting an historical approach. The aim is to clarify the nature of the correspondence between 'dual particles' in the light of a historical analysis of the developments of the idea of weak/strong duality, starting with Dirac's electric-magnetic duality and its successive generalizations in the context of (Abelian and non-Abelian) field theory, to arrive at its first extension to string theory. This analysis is then used as evidential basis for discussing the 'elementary/composite' divide and, after taking another historical detour by analyzing an instructive analogy case (DHS duality and related nuclear democracy), drawing some conclusions on the particle-democracy issue.

Economic modelling with low-cognition agents

NASA Astrophysics Data System (ADS)

Ormerod, Paul

2006-10-01

The standard socio-economic model (SSSM) postulates very considerable cognitive powers on the part of its agents. They are able to gather all relevant information in any given situation, and to take the optimal decision on the basis of it, given their tastes and preferences. This behavioural rule is postulated to be universal. The concept of bounded rationality relaxes this somewhat, by permitting agents to have access to only limited amounts of information. But agents still optimise subject to their information set and tastes. Empirical work in economics over the past 20 years or so has shown that in general these behavioural postulates lack empirical validity. Instead, agents appear to have limited ability to gather information, and use simple rules of thumb to process the information which they have in order to take decisions. Building theoretical models on these realistic foundations which give better accounts of empirical phenomena than does the SSSM is an important challenge to both economists and econophysicists. Considerable progress has already been made in a short space of time, and examples are given in this paper.

Operational Axioms for Quantum Mechanics

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

D'Ariano, Giacomo Mauro; Department of Electrical and Computer Engineering, Northwestern University, Evanston, IL 60208

2007-02-21

The mathematical formulation of Quantum Mechanics in terms of complex Hilbert space is derived for finite dimensions, starting from a general definition of physical experiment and from five simple Postulates concerning experimental accessibility and simplicity. For the infinite dimensional case, on the other hand, a C*-algebra representation of physical transformations is derived, starting from just four of the five Postulates via a Gelfand-Naimark-Segal (GNS) construction. The present paper simplifies and sharpens the previous derivation in Ref. [1]. The main ingredient of the axiomatization is the postulated existence of faithful states that allows one to calibrate the experimental apparatus. Such notionmore » is at the basis of the operational definitions of the scalar product and of the transposed of a physical transformation. What is new in the present paper with respect to Ref. [1], is the operational deduction of an involution corresponding to the complex-conjugation for effects, whose extension to transformations allows to define the adjoint of a transformation when the extension is composition-preserving. The existence of such composition-preserving extension among possible extensions is analyzed.« less

Processing concrete words: fMRI evidence against a specific right-hemisphere involvement.

PubMed

Fiebach, Christian J; Friederici, Angela D

2004-01-01

Behavioral, patient, and electrophysiological studies have been taken as support for the assumption that processing of abstract words is confined to the left hemisphere, whereas concrete words are processed also by right-hemispheric brain areas. These are thought to provide additional information from an imaginal representational system, as postulated in the dual-coding theory of memory and cognition. Here we report new event-related fMRI data on the processing of concrete and abstract words in a lexical decision task. While abstract words activated a subregion of the left inferior frontal gyrus (BA 45) more strongly than concrete words, specific activity for concrete words was observed in the left basal temporal cortex. These data as well as data from other neuroimaging studies reviewed here are not compatible with the assumption of a specific right-hemispheric involvement for concrete words. The combined findings rather suggest a revised view of the neuroanatomical bases of the imaginal representational system assumed in the dual-coding theory, at least with respect to word recognition.

Avco Lycoming/NASA contract status. [on reduction of emissions from aircraft piston engines

NASA Technical Reports Server (NTRS)

Duke, L. C.

1976-01-01

The standards promulgated by the Environmental Protection Agency (EPA) for carbon monoxide (CO), unburned hydrocarbon (HC), and oxides-of-nitrogen (NOx) emissions were the basis in a study of ways to reduce emissions from aircraft piston engines. A variable valve timing system, ultrasonic fuel atomization, and ignition system changes were postulated.

An Investigation of Visual, Aural, Motion and Control Movement Cues.

ERIC Educational Resources Information Center

Matheny, W. G.; And Others

A study was conducted to determine the ways in which multi-sensory cues can be simulated and effectively used in the training of pilots. Two analytical bases, one called the stimulus environment approach and the other an information array approach, are developed along with a cue taxonomy. Cues are postulated on the basis of information gained from…

Digital Avionics Information System (DAIS): Impact of DAIS Concept on Life Cycle Cost. Final Report.

ERIC Educational Resources Information Center

Goclowski, John C.; And Others

Designed to identify and quantify the potential impacts of the Digital Avionics Information System (DAIS) on weapon system personnel requirements and life cycle cost (LCC), this study postulated a typical close-air-support (CAS) mission avionics suite to serve as a basis for comparing present day and DAIS configuration specifications. The purpose…

The Role of Voluntariness in Distance Education Students' Usage of a Course Website

ERIC Educational Resources Information Center

Ramayah, T.

2010-01-01

This study looks at the usage of a course website among distance learning business management students in a public institution of higher learning in Malaysia. The Technology Acceptance Model (TAM) was used as the basis of the research framework but voluntariness was added as a possible moderating factor. TAM postulates that perceived usefulness…

The Attributive Theory of Quality: A Model for Quality Measurement in Higher Education.

ERIC Educational Resources Information Center

Afshar, Arash

A theoretical basis for defining and measuring the quality of institutions of higher education, namely for accreditation purposes, is developed. The theory, the Attributive Theory of Quality, is illustrated using a calculation model that is based on general systems theory. The theory postulates that quality only exists in relation to the…

Diffusion of Innovation Theory: A Bridge for the Research-Practice Gap in Counseling

ERIC Educational Resources Information Center

Murray, Christine E.

2009-01-01

This article presents a diffusion of innovation theory-based framework for addressing the gap between research and practice in the counseling profession. The author describes the nature of the research-practice gap and presents an overview of diffusion of innovation theory. On the basis of the application of several major postulates of diffusion…

Dual-energy micro-CT imaging for differentiation of iodine- and gold-based nanoparticles

NASA Astrophysics Data System (ADS)

Badea, C. T.; Johnston, S. M.; Qi, Y.; Ghaghada, K.; Johnson, G. A.

2011-03-01

Spectral CT imaging is expected to play a major role in the diagnostic arena as it provides material decomposition on an elemental basis. One fascinating possibility is the ability to discriminate multiple contrast agents targeting different biological sites. We investigate the feasibility of dual energy micro-CT for discrimination of iodine (I) and gold (Au) contrast agents when simultaneously present in the body. Simulations and experiments were performed to measure the CT enhancement for I and Au over a range of voltages from 40-to-150 kVp using a dual source micro-CT system. The selected voltages for dual energy micro-CT imaging of Au and I were 40 kVp and 80 kVp. On a massconcentration basis, the relative average enhancement of Au to I was 2.75 at 40 kVp and 1.58 at 80 kVp. We have demonstrated the method in a preclinical model of colon cancer to differentiate vascular architecture and extravasation. The concentration maps of Au and I allow quantitative measure of the bio-distribution of both agents. In conclusion, dual energy micro-CT can be used to discriminate probes containing I and Au with immediate impact in pre-clinical research.

Dual therapy with infliximab and immunomodulator reduces one-year rates of hospitalization and surgery among veterans with inflammatory bowel disease.

PubMed

Abraham, Neena S; Richardson, Peter; Castillo, Diana; Kane, Sunanda V

2013-10-01

Effectiveness of early treatment with biologics and immunomodulator therapy on healthcare utilization remains poorly defined. We assessed rates of hospitalization and surgery within 1 year after initiation of infliximab and/or immunomodulator therapy in a United States cohort of patients with inflammatory bowel disease. We conducted a retrospective, observational cohort study of veterans with Crohn's disease or ulcerative colitis by using administrative data from 176 Department of Veteran Affairs facilities (October 1, 2001 through September 30, 2009). Inpatient, outpatient, and death records were linked longitudinally with prescription fill data. Each person-day of follow-up was assessed for treatment with infliximab, immunomodulators, both (dual therapy), or neither. We calculated drug exposure time and used Poisson and logistic regression analyses to assess outcomes. The cohort of 20,474 patients included 8042 patients with Crohn's disease and 12,432 with ulcerative colitis (93.9% male; 72.5% white; mean age, 60.9 ± 14.5 years) prescribed infliximab (0.17%), immunomodulator (1.3%), or dual therapy (1.5%). Adjusted models revealed 50% relative reductions in hospitalization among patients who received 9.2 months of immunomodulator monotherapy, 8 months of infliximab, or 7.7 months of dual therapy. A 50% relative reduction in surgery was observed among patients receiving 7 months of infliximab or 5 months of dual therapy. Analysis of dose-response data revealed 73.1% and 92% reductions in risk of hospitalization and surgery, respectively, after 9 months of dual therapy. On the basis of a retrospective cohort study, dual therapy with infliximab and an immunomodulator for <8 months is associated with significant reductions in hospitalization and surgery within 1 year of the start of therapy. These findings indicate that patients with IBD are more likely to benefit if dual therapy is initiated earlier in their first year of therapy. Copyright © 2013 AGA Institute. Published by Elsevier Inc. All rights reserved.

On Anticipatory Development of Dual Education Based on the Systemic Approach

ERIC Educational Resources Information Center

Alshynbayeva, Zhuldyz; Sarbassova, Karlygash; Galiyeva, Temir; Kaltayeva, Gulnara; Bekmagambetov, Aidos

2016-01-01

The article addresses separate theoretical and methodical aspects of the anticipatory development of dual education in the Republic of Kazakhstan based on the systemic approach. It states the need to develop orientating basis of prospective professional activities in students. We define the concepts of anticipatory cognition and anticipatory…

The polynomial form of the scattering equations is an H -basis

NASA Astrophysics Data System (ADS)

Bosma, Jorrit; Søgaard, Mads; Zhang, Yang

2016-08-01

We prove that the polynomial form of the scattering equations is a Macaulay H -basis. We demonstrate that this H -basis facilitates integrand reduction and global residue computations in a way very similar to using a Gröbner basis, but circumvents the heavy computation of the latter. As an example, we apply the H -basis to prove the conjecture that the dual basis of the polynomial scattering equations must contain one constant term.

Correction of energy-dependent systematic errors in dual-energy X-ray CT using a basis material coefficients transformation method

NASA Astrophysics Data System (ADS)

Goh, K. L.; Liew, S. C.; Hasegawa, B. H.

1997-12-01

Computer simulation results from our previous studies showed that energy dependent systematic errors exist in the values of attenuation coefficient synthesized using the basis material decomposition technique with acrylic and aluminum as the basis materials, especially when a high atomic number element (e.g., iodine from radiographic contrast media) was present in the body. The errors were reduced when a basis set was chosen from materials mimicking those found in the phantom. In the present study, we employed a basis material coefficients transformation method to correct for the energy-dependent systematic errors. In this method, the basis material coefficients were first reconstructed using the conventional basis materials (acrylic and aluminum) as the calibration basis set. The coefficients were then numerically transformed to those for a more desirable set materials. The transformation was done at the energies of the low and high energy windows of the X-ray spectrum. With this correction method using acrylic and an iodine-water mixture as our desired basis set, computer simulation results showed that accuracy of better than 2% could be achieved even when iodine was present in the body at a concentration as high as 10% by mass. Simulation work had also been carried out on a more inhomogeneous 2D thorax phantom of the 3D MCAT phantom. The results of the accuracy of quantitation were presented here.

Third-Order Incremental Dual-Basis Set Zero-Buffer Approach: An Accurate and Efficient Way To Obtain CCSD and CCSD(T) Energies.

PubMed

Zhang, Jun; Dolg, Michael

2013-07-09

An efficient way to obtain accurate CCSD and CCSD(T) energies for large systems, i.e., the third-order incremental dual-basis set zero-buffer approach (inc3-db-B0), has been developed and tested. This approach combines the powerful incremental scheme with the dual-basis set method, and along with the new proposed K-means clustering (KM) method and zero-buffer (B0) approximation, can obtain very accurate absolute and relative energies efficiently. We tested the approach for 10 systems of different chemical nature, i.e., intermolecular interactions including hydrogen bonding, dispersion interaction, and halogen bonding; an intramolecular rearrangement reaction; aliphatic and conjugated hydrocarbon chains; three compact covalent molecules; and a water cluster. The results show that the errors for relative energies are <1.94 kJ/mol (or 0.46 kcal/mol), for absolute energies of <0.0026 hartree. By parallelization, our approach can be applied to molecules of more than 30 atoms and more than 100 correlated electrons with high-quality basis set such as cc-pVDZ or cc-pVTZ, saving computational cost by a factor of more than 10-20, compared to traditional implementation. The physical reasons of the success of the inc3-db-B0 approach are also analyzed.

Application of the dual-component model of working memory to ADHD:Greater secondary memory deficit despite confounded cognitive differences.

PubMed

Gibson, Bradley S; Gondoli, Dawn M; Ralph, Kathryn J; Sztybel, Pedro

2018-01-01

The dual-component model postulates that working memory capacity consists of two dissociable components: maintenance in primary memory (PM) and retrieval from secondary memory (SM). Recent application of this model to attention-deficit/hyperactivity disorder (ADHD) has revealed that the SM component is more deficient than the PM component across both verbal and spatial modalities. The present study attempts to strengthen this conclusion by addressing two weaknesses in the previous study. First, the present study shows that the SM component continues to be more deficient than the PM component across both modalities under conditions in which (1) all participants were instructed to use the same recall strategy (resulting in the exclusion of fewer participants); and, (2) individual differences in this strategy were controlled. Second, the present study also documents a group difference in word reading efficiency that is confounded with diagnostic status and that might have influenced estimates of PM and SM capacities in the verbal modality. However, although the SM component is more deficient than the PM component in the ADHD group, the magnitude of this interaction does not vary as a function task modality. These findings are interpreted to suggest that the pattern of WM deficiencies observed are part of a causal pathway that can lead to the symptoms of ADHD, as well as to impairments in reading (and intelligence) due to overlapping cue-dependent retrieval mechanisms. These findings provide additional support for the notion that the SM component of WM is an important and neglected target for treatment.

Beamspace dual signal space projection (bDSSP): a method for selective detection of deep sources in MEG measurements.

PubMed

Sekihara, Kensuke; Adachi, Yoshiaki; Kubota, Hiroshi K; Cai, Chang; Nagarajan, Srikantan S

2018-06-01

Magnetoencephalography (MEG) has a well-recognized weakness at detecting deeper brain activities. This paper proposes a novel algorithm for selective detection of deep sources by suppressing interference signals from superficial sources in MEG measurements. The proposed algorithm combines the beamspace preprocessing method with the dual signal space projection (DSSP) interference suppression method. A prerequisite of the proposed algorithm is prior knowledge of the location of the deep sources. The proposed algorithm first derives the basis vectors that span a local region just covering the locations of the deep sources. It then estimates the time-domain signal subspace of the superficial sources by using the projector composed of these basis vectors. Signals from the deep sources are extracted by projecting the row space of the data matrix onto the direction orthogonal to the signal subspace of the superficial sources. Compared with the previously proposed beamspace signal space separation (SSS) method, the proposed algorithm is capable of suppressing much stronger interference from superficial sources. This capability is demonstrated in our computer simulation as well as experiments using phantom data. The proposed bDSSP algorithm can be a powerful tool in studies of physiological functions of midbrain and deep brain structures.

Beamspace dual signal space projection (bDSSP): a method for selective detection of deep sources in MEG measurements

NASA Astrophysics Data System (ADS)

Sekihara, Kensuke; Adachi, Yoshiaki; Kubota, Hiroshi K.; Cai, Chang; Nagarajan, Srikantan S.

2018-06-01

Objective. Magnetoencephalography (MEG) has a well-recognized weakness at detecting deeper brain activities. This paper proposes a novel algorithm for selective detection of deep sources by suppressing interference signals from superficial sources in MEG measurements. Approach. The proposed algorithm combines the beamspace preprocessing method with the dual signal space projection (DSSP) interference suppression method. A prerequisite of the proposed algorithm is prior knowledge of the location of the deep sources. The proposed algorithm first derives the basis vectors that span a local region just covering the locations of the deep sources. It then estimates the time-domain signal subspace of the superficial sources by using the projector composed of these basis vectors. Signals from the deep sources are extracted by projecting the row space of the data matrix onto the direction orthogonal to the signal subspace of the superficial sources. Main results. Compared with the previously proposed beamspace signal space separation (SSS) method, the proposed algorithm is capable of suppressing much stronger interference from superficial sources. This capability is demonstrated in our computer simulation as well as experiments using phantom data. Significance. The proposed bDSSP algorithm can be a powerful tool in studies of physiological functions of midbrain and deep brain structures.

Sequential detection of different antigens induced by Epstein-Barr virus and herpes simplex virus in the same Western blot by using dual antibody probes.

PubMed

Lin, J C; Pagano, J S

1986-08-01

A dual antibody probing technique that permitted a color-coded identification of polypeptides representing different classes of Epstein-Barr virus (EBV) antigens as well as differentiation of the polypeptides induced by different herpesviruses in the same Western blot was developed. When the nitrocellulose sheet was probed first with monoclonal antibody against EBV early antigen diffuse component (EA-D) and then stained with 4-chloro-1-naphthol, four polypeptides specific for EA-D were identified by purple bands. Subsequently, the same nitrocellulose sheet was reprobed with human serum containing antibodies against EBV early antigen, viral capsid antigen, and nuclear antigen and stained with 3,3'-diaminobenzidine. Several brown bands corresponding to early, viral capsid, and nuclear antigen polypeptides were detected. The dual antibody probing technique was used in an analysis to differentiate polypeptides resulting from either EBV or herpes simplex virus infection, either in cells infected by individual virus or in a cell line dually infected by both viruses. On the basis of different colored bands in different lanes of the same gel, 20 polypeptides with molecular weights ranging from 31,000 to 165,000 were identified as herpes simplex virus-specific proteins. These results suggested that the dual antibody probing technique may be applicable in clinical diagnosis for detecting antigens and antibodies derived from different pathogens.

Complex regulation of GH autofeedback under dual-peptide drive: studies under a pharmacological GH and sex steroid clamp

PubMed Central

Erickson, Dana; Miles, John M.; Bowers, Cyril Y.

2011-01-01

To test the postulate that sex difference, sex steroids, and peptidyl secretagogues control GH autofeedback, 11 healthy postmenopausal women and 14 older men were each given 1) a single iv pulse of GH to enforce negative feedback and 2) continuous iv infusion of saline vs. combined GHRH/GHRP-2 to drive feedback escape during pharmacological estradiol (E2; women) or testosterone (T; men) supplementation vs. placebo in a double-blind, prospectively randomized crossover design. By three-way ANCOVA, sex difference, sex hormone treatment, peptide stimulation, and placebo/saline responses (covariate) controlled total (integrated) GH recovery during feedback (each P < 0.001). Both sex steroid milieu (P = 0.019) and dual-peptide stimulation (P < 0.001) determined nadir (maximally feedback-suppressed) GH concentrations. E2/T exposure elevated nadir GH concentrations during saline infusion (P = 0.003), whereas dual-peptide infusion did so independently of T/E2 and sex difference (P = 0.001). All three of sex difference (P = 0.001), sex steroid treatment (P = 0.005), and double-peptide stimulation (P < 0.001) augmented recovery of peak (maximally feedback-escaped) GH concentrations. Peak GH responses to dual-peptidyl agonists were greater in women than in men (P = 0.016). E2/T augmented peak GH recovery during saline infusion (P < 0.001). Approximate entropy analysis corroborated independent effects of sex steroid treatment (P = 0.012) and peptide infusion (P < 0.001) on GH regularity. In summary, sex difference, sex steroid supplementation, and combined peptide drive influence nadir, peak, and entropic measurements of GH release under controlled negative feedback. To the degree that the pharmacological sex steroid, GH, and dual-peptide clamps provide prephysiological regulatory insights, these outcomes suggest major determinants of pulsatile GH secretion in the feedback domain. PMID:21467302

Structural reliability calculation method based on the dual neural network and direct integration method.

PubMed

Li, Haibin; He, Yun; Nie, Xiaobo

2018-01-01

Structural reliability analysis under uncertainty is paid wide attention by engineers and scholars due to reflecting the structural characteristics and the bearing actual situation. The direct integration method, started from the definition of reliability theory, is easy to be understood, but there are still mathematics difficulties in the calculation of multiple integrals. Therefore, a dual neural network method is proposed for calculating multiple integrals in this paper. Dual neural network consists of two neural networks. The neural network A is used to learn the integrand function, and the neural network B is used to simulate the original function. According to the derivative relationships between the network output and the network input, the neural network B is derived from the neural network A. On this basis, the performance function of normalization is employed in the proposed method to overcome the difficulty of multiple integrations and to improve the accuracy for reliability calculations. The comparisons between the proposed method and Monte Carlo simulation method, Hasofer-Lind method, the mean value first-order second moment method have demonstrated that the proposed method is an efficient and accurate reliability method for structural reliability problems.

Molecular Clues to Physiological and Premature Ageing Revealed | Center for Cancer Research

Cancer.gov

There are many theories about the molecular basis of ageing. One of the most popular ones postulates that organisms age by accumulating damage to their tissues, cells, and molecules. On the cellular level, ageing is associated with progressive changes in chromatin (a combination of DNA and proteins that makes up chromosomes). These changes include loss of chromatin structure,

Complex quantum enveloping algebras as twisted tensor products

NASA Astrophysics Data System (ADS)

Chryssomalakos, Chryssomalis; Engeldinger, Ralf A.; Jurčo, Branislav; Schlieker, Michael; Zumino, Bruno

1994-12-01

We introduce a *-structure on the quantum double and its dual in order to make contact with various approaches to the enveloping algebras of complex quantum groups. Furthermore, we introduce a canonical basis in the quantum double, its universal R-matrices and give its relation to subgroups in the dual Hopf algebra.

Design and synthesis of dual inhibitors of acetylcholinesterase and serotonin transporter targeting potential agents for Alzheimer's disease.

PubMed

Kogen, Hiroshi; Toda, Narihiro; Tago, Keiko; Marumoto, Shinji; Takami, Kazuko; Ori, Mayuko; Yamada, Naho; Koyama, Kazuo; Naruto, Shunji; Abe, Kazumi; Yamazaki, Reina; Hara, Takao; Aoyagi, Atsushi; Abe, Yasuyuki; Kaneko, Tsugio

2002-10-03

Highly efficient acetylcholinesterase (AChE) and serotonin transporter (SERT) dual inhibitors, (S)-4 and (R)-13 were designed and synthesized on the basis of the hypothetical model of AChE active site. Both compounds showed potent inhibitory activities against AChE and SERT. [structure: see text

Elaborations on the Socioegocentric and Dual-Level Connectionist Models of Group Interaction Processes

ERIC Educational Resources Information Center

Hewes, Dean E.

2009-01-01

The purpose of the author's contribution to this colloquy was to spark conversation on the theoretical nature of communication processes and the evidentiary requirements for testing their relationship to group outcomes. Co-discussants have raised important issues concerning the philosophical basis of the socioegocentric model (SM) and dual-level…

The Molecular Basis for Dual Fatty Acid Amide Hydrolase (FAAH)/Cyclooxygenase (COX) Inhibition.

PubMed

Palermo, Giulia; Favia, Angelo D; Convertino, Marino; De Vivo, Marco

2016-06-20

The design of multitarget-directed ligands is a promising strategy for discovering innovative drugs. Here, we report a mechanistic study that clarifies key aspects of the dual inhibition of the fatty acid amide hydrolase (FAAH) and the cyclooxygenase (COX) enzymes by a new multitarget-directed ligand named ARN2508 (2-[3-fluoro-4-[3-(hexylcarbamoyloxy)phenyl]phenyl]propanoic acid). This potent dual inhibitor combines, in a single scaffold, the pharmacophoric elements often needed to block FAAH and COX, that is, a carbamate moiety and the 2-arylpropionic acid functionality, respectively. Molecular modeling and molecular dynamics simulations suggest that ARN2508 uses a noncovalent mechanism of inhibition to block COXs, while inhibiting FAAH via the acetylation of the catalytic Ser241, in line with previous experimental evidence for covalent FAAH inhibition. This study proposes the molecular basis for the dual FAAH/COX inhibition by this novel hybrid scaffold, stimulating further experimental studies and offering new insights for the rational design of novel anti-inflammatory agents that simultaneously act on FAAH and COX. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

An Initial Assessment of the Surface Reference Technique Applied to Data from the Dual-Frequency Precipitation Radar (DPR) on the GPM Satellite

NASA Technical Reports Server (NTRS)

Meneghini, Robert; Kim, Hyokyung; Liao, Liang; Jones, Jeffrey A.; Kwiatkowski, John M.

2015-01-01

It has long been recognized that path-integrated attenuation (PIA) can be used to improve precipitation estimates from high-frequency weather radar data. One approach that provides an estimate of this quantity from airborne or spaceborne radar data is the surface reference technique (SRT), which uses measurements of the surface cross section in the presence and absence of precipitation. Measurements from the dual-frequency precipitation radar (DPR) on the Global Precipitation Measurement (GPM) satellite afford the first opportunity to test the method for spaceborne radar data at Ka band as well as for the Ku-band-Ka-band combination. The study begins by reviewing the basis of the single- and dual-frequency SRT. As the performance of the method is closely tied to the behavior of the normalized radar cross section (NRCS or sigma(0)) of the surface, the statistics of sigma(0) derived from DPR measurements are given as a function of incidence angle and frequency for ocean and land backgrounds over a 1-month period. Several independent estimates of the PIA, formed by means of different surface reference datasets, can be used to test the consistency of the method since, in the absence of error, the estimates should be identical. Along with theoretical considerations, the comparisons provide an initial assessment of the performance of the single- and dual-frequency SRT for the DPR. The study finds that the dual-frequency SRT can provide improvement in the accuracy of path attenuation estimates relative to the single-frequency method, particularly at Ku band.

Linear free energy relationships of the 1H and 13C NMR chemical shifts of 3-methylene-2-substituted-1,4-pentadienes

NASA Astrophysics Data System (ADS)

Valentić, Nataša V.; Vitnik, Željko; Kozhushkov, Sergei I.; de Meijere, Armin; Ušćumlić, Gordana S.; Juranić, Ivan O.

2005-06-01

Linear free energy relationships (LFER) were applied to the 1H and 13C NMR chemical shifts ( δN, N= 1H and 13C, respectively) in the unsaturated backbone of cross-conjugated trienes 3-methylene-2-substituted-1,4-pentadienes. The NMR data were correlated using five different LFER models, based on the mono, the dual and the triple substituent parameter (MSP, DSP and TSP, respectively) treatment. The simple and extended Hammett equations, and the three postulated unconventional LFER models obtained by adaptation of the later, were used. The geometry data, which are needed in Karplus-type and McConnell-type analysis, were obtained using semi-empirical MNDO-PM3 calculations. In correlating the data the TSP approach was more successful than the MSP and DSP approaches. The fact that the calculated molecular geometries allow accurate prediction of the NMR data confirms the validity of unconventional LFER models used. These results suggest the s- cis conformation of the cross-conjugated triene as the preferred one. Postulated unconventional DSP and TSP equations enable the assessment of electronic substituent effects in the presence of other interfering influences.

Dual agency, dual relationships, boundary crossings, and associated boundary violations: a survey of military and civilian psychiatrists.

PubMed

Hines, A H; Ader, D N; Chang, A S; Rundell, J R

1998-12-01

We hypothesized that psychiatrists with high dual-agency potential (military and health maintenance organization [HMO] psychiatrists) were more likely than non-HMO civilian psychiatrists to engage in dual relationships, report pressures to do so, participate in other general boundary-crossing activities, and report associated counter-therapeutic outcomes (boundary violations). Ninety military and 191 demographically matched civilian psychiatrists reported the number of boundary-crossing activities (including dual relationships) and associated counter-therapeutic outcomes in the preceding year with adult patients. Military and HMO psychiatrists reported greater external pressures than non-HMO civilian psychiatrists to engage in dual relationships; however, all three groups were similar in their reported numbers of dual relationships. The reported boundary-crossing activities and dual relationships studied here are not necessarily associated with reported boundary violations. The relative risk of a particular boundary crossing associating with harm to a patient likely depends on the therapeutic context and should be determined on a case-by-case basis.

Whiplash injuries of the temporomandibular joint in motor vehicle accidents: speculations and facts.

PubMed

McKay, D C; Christensen, L V

1998-10-01

Referring to the temporomandibular joint (TMJ) of the human mandibular locomotor system, it has been asserted that displacement of the TMJ disc and inflammation of TMJ tissues are the results of acute and indirect trauma to the TMJ; on occasion this is allegedly experienced in motor vehicle accidents and commonly known as a TMJ whiplash injury. It is postulated that the TMJ whiplash injury is released in the occupant or occupants of a target vehicle when its rear end is impacted by the front end of a bullet vehicle. On the basis of detailed analyses of TMJ trauma/pain histories and TMJ magnetic resonance images, presented as circumstantial evidence in favour of the postulated TMJ whiplash injury, and detailed analyses of the mathematical biophysics of the mandibular locomotor system as well as direct experimental evidence, it is concluded that the postulated TMJ whiplash injury does not exist as a single and independent disease entity caused by motor vehicle accidents. If TMJ disc displacement and inflammation are present, they are expressions of an insidious and progressive pre-existing (pre-accident) disease entity that is comprised of TMJ synovitis/osteoarthritis (phase of inflammation with presence of immune system cells), TMJ internal derangement (phase of disc displacement and deformation with presence of proteinases), and TMJ osteoarthrosis (phase of degeneration with absence of immune system cells). For the asserted TMJ whiplash manoeuvre and ensuing injury to occur as postulated, the laws of physics and biology would have to be suspended.

Upgrade of the 92 GHz airborne multi-channel meteorological radiometer (AMMR)

NASA Technical Reports Server (NTRS)

Kunkee, D. B.; Gasiewski, A. J.

1994-01-01

The AMMR 92 GHz dual polarized radiometer (AMMR-92) has been used to perform experiments in the Laboratory for Radioscience and Remote Sensing at Georgia Tech during two periods, the first period was from March 1991 to November 1992, and the second period was from March 1993 to September 1993. Early in the first period a polarization correlation channel was added to the radiometer. This new channel can be configured to measure the third (Re(E(sub v)E(sub h)(sup *)) or fourth (Im(E(sub v)E(sub h)(sup *)) Stokes parameter in the radiometer's feedhorn polarization basis. Operation of the instrument as a polarization correlating radiometer is does not affect its originally intended operation as a dual-polarized radiometer. Investigations with the AMMR-92 at Georgia Tech have uncovered some problems which may compromise the accuracy of the instrument. These problems are not related to the installation of the new cross-correlating channel but are inherent in the original design. This report discusses the following topics: (1) Splash-plate alignment; (2) Replacement of calibration load with pyramidal type; (3) Mixer upgrade; and (4) Installation of a video blanking circuit.

Dual Language Use in Sign-Speech Bimodal Bilinguals: fNIRS Brain-Imaging Evidence

ERIC Educational Resources Information Center

Kovelman, Ioulia; Shalinsky, Mark H.; White, Katherine S.; Schmitt, Shawn N.; Berens, Melody S.; Paymer, Nora; Petitto, Laura-Ann

2009-01-01

The brain basis of bilinguals' ability to use two languages at the same time has been a hotly debated topic. On the one hand, behavioral research has suggested that bilingual dual language use involves complex and highly principled linguistic processes. On the other hand, brain-imaging research has revealed that bilingual language switching…

Division of Labor in German Dual-Earner Families: Testing Equity Theoretical Hypotheses

ERIC Educational Resources Information Center

Klumb, Petra; Hoppmann, Christiane; Staats, Melanie

2006-01-01

On the basis of 52 German dual-earner couples with at least 1 child younger than 5 years, we tested the effects of an unequal division of labor on relationship satisfaction. We analyzed diary reports of time allocated to productive activities according to the actor-partner-interdependence model. Hierarchical linear models showed that rather than…

78 FR 39781 - Consequence Study of a Beyond-Design-Basis Earthquake Affecting the Spent Fuel Pool for a U.S...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-02

... Spent Fuel Pool Study). The purpose of this study was to examine if faster removal of older, colder... NRC Library at http://www.nrc.gov/reading-rm/adams.html . To begin the search, select ``ADAMS Public... of postulated spent fuel pool accidents. The purpose of this study is to examine if faster removal of...

Teaching Thermodynamics of Ideal Solutions: An Entropy-Based Approach to Help Students Better Understand and Appreciate the Subtleties of Solution Models

ERIC Educational Resources Information Center

Tomba, J. Pablo

2015-01-01

The thermodynamic formalism of ideal solutions is developed in most of the textbooks postulating a form for the chemical potential of a generic component, which is adapted from the thermodynamics of ideal gas mixtures. From this basis, the rest of useful thermodynamic properties can be derived straightforwardly without further hypothesis. Although…

Dual renin-angiotensin-aldosterone system blockade for diabetic kidney disease.

PubMed

Pichler, Raimund H; de Boer, Ian H

2010-08-01

Blockade of the renin-angiotensin-aldosterone system (RAAS) prevents the development and progression of diabetic kidney disease (DKD). It is controversial whether the simultaneous use of two RAAS inhibitors (ie, dual RAAS blockade) further improves renal outcomes. This review examines the scientific rationale and current clinical evidence addressing the use of dual RAAS blockade to prevent and treat DKD. It is concluded that dual RAAS blockade should not be routinely applied to patients with low or moderate risk of progressive kidney disease (normoalbuminuria or microalbuminuria with preserved glomerular filtration rate). For patients with high risk of progressive kidney disease (substantial albuminuria or impaired glomerular filtration rate), clinicians should carefully weigh the potential risks and benefits of dual RAAS blockade on an individual basis until ongoing clinical trials provide further insight.

"Role magnets"? An empirical investigation of popularity trajectories for life-course persistent individuals during adolescence.

PubMed

Young, Jacob T N

2014-01-01

Recent scholarship has focused on the role of social status in peer groups to explain the fact that delinquency is disproportionately committed during adolescence. Yet, the precise mechanism linking adolescence, social status, and antisocial behavior is not well understood. Dual-taxonomy postulates a testable mechanism that links the sudden increase in risky behavior among adolescents to the social magnetism of a small group of persistently antisocial individuals, referred to here as the "role magnet" hypothesis. Using semi-parametric group-based trajectory modeling and growth-curve modeling, this study provides the first test of this hypothesis by examining physical violence and popularity trajectories for 1,845 male respondents age 11-32 from a nationally representative sample (54 % non-Hispanic White; 21 % non-Hispanic African American; 17 % Hispanic; 8 % Asian). Individuals assigned to a "chronic violence" trajectory group showed consistently lower average levels of popularity from 11 to 19. But, these same individuals experienced increases in popularity during early adolescence and subsequent declines in late adolescence. These findings are linked to current research examining social status as a mechanism generating antisocial behavior during adolescence and the consequences of delayed entry into adult roles.

Climate, Water, and Human Health: Large Scale Hydroclimatic Controls in Forecasting Cholera Epidemics

NASA Astrophysics Data System (ADS)

Akanda, A. S.; Jutla, A. S.; Islam, S.

2009-12-01

Despite ravaging the continents through seven global pandemics in past centuries, the seasonal and interannual variability of cholera outbreaks remain a mystery. Previous studies have focused on the role of various environmental and climatic factors, but provided little or no predictive capability. Recent findings suggest a more prominent role of large scale hydroclimatic extremes - droughts and floods - and attempt to explain the seasonality and the unique dual cholera peaks in the Bengal Delta region of South Asia. We investigate the seasonal and interannual nature of cholera epidemiology in three geographically distinct locations within the region to identify the larger scale hydroclimatic controls that can set the ecological and environmental ‘stage’ for outbreaks and have significant memory on a seasonal scale. Here we show that two distinctly different, pre and post monsoon, cholera transmission mechanisms related to large scale climatic controls prevail in the region. An implication of our findings is that extreme climatic events such as prolonged droughts, record floods, and major cyclones may cause major disruption in the ecosystem and trigger large epidemics. We postulate that a quantitative understanding of the large-scale hydroclimatic controls and dominant processes with significant system memory will form the basis for forecasting such epidemic outbreaks. A multivariate regression method using these predictor variables to develop probabilistic forecasts of cholera outbreaks will be explored. Forecasts from such a system with a seasonal lead-time are likely to have measurable impact on early cholera detection and prevention efforts in endemic regions.

SO(N) restricted Schur polynomials

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

Kemp, Garreth, E-mail: garreth.kemp@students.wits.ac.za

2015-02-15

We focus on the 1/4-BPS sector of free super Yang-Mills theory with an SO(N) gauge group. This theory has an AdS/CFT (an equivalence between a conformal field theory in d-1 dimensions and type II string theory defined on an AdS space in d-dimensions) dual in the form of type IIB string theory with AdS{sub 5}×RP{sup 5} geometry. With the aim of studying excited giant graviton dynamics, we construct an orthogonal basis for this sector of the gauge theory in this work. First, we demonstrate that the counting of states, as given by the partition function, and the counting of restrictedmore » Schur polynomials match by restricting to a particular class of Young diagram labels. We then give an explicit construction of these gauge invariant operators and evaluate their two-point function exactly. This paves the way to studying the spectral problem of these operators and their D-brane duals.« less

Dual RBFNNs-Based Model-Free Adaptive Control With Aspen HYSYS Simulation.

PubMed

Zhu, Yuanming; Hou, Zhongsheng; Qian, Feng; Du, Wenli

2017-03-01

In this brief, we propose a new data-driven model-free adaptive control (MFAC) method with dual radial basis function neural networks (RBFNNs) for a class of discrete-time nonlinear systems. The main novelty lies in that it provides a systematic design method for controller structure by the direct usage of I/O data, rather than using the first-principle model or offline identified plant model. The controller structure is determined by equivalent-dynamic-linearization representation of the ideal nonlinear controller, and the controller parameters are tuned by the pseudogradient information extracted from the I/O data of the plant, which can deal with the unknown nonlinear system. The stability of the closed-loop control system and the stability of the training process for RBFNNs are guaranteed by rigorous theoretical analysis. Meanwhile, the effectiveness and the applicability of the proposed method are further demonstrated by the numerical example and Aspen HYSYS simulation of distillation column in crude styrene produce process.

Improved performance of nanoscale junctionless tunnel field-effect transistor based on gate engineering approach

NASA Astrophysics Data System (ADS)

Molaei Imen Abadi, Rouzbeh; Sedigh Ziabari, Seyed Ali

2016-11-01

In this paper, a first qualitative study on the performance characteristics of dual-work function gate junctionless TFET (DWG-JLTFET) on the basis of energy band profile modulation is investigated. A dual-work function gate technique is used in a JLTFET in order to create a downward band bending on the source side similar to PNPN structure. Compared with the single-work function gate junctionless TFET (SWG-JLTFET), the numerical simulation results demonstrated that the DWG-JLTFET simultaneously optimizes the ON-state current, the OFF-state leakage current, and the threshold voltage and also improves average subthreshold slope. It is illustrated that if appropriate work functions are selected for the gate materials on the source side and the drain side, the JLTFET exhibits a considerably improved performance. Furthermore, the optimization design of the tunnel gate length ( L Tun) for the proposed DWG-JLTFET is studied. All the simulations are done in Silvaco TCAD for a channel length of 20 nm using the nonlocal band-to-band tunneling (BTBT) model.

Two-dimensional analytical model for dual-material control-gate tunnel FETs

NASA Astrophysics Data System (ADS)

Xu, Hui Fang; Dai, Yue Hua; Gui Guan, Bang; Zhang, Yong Feng

2016-09-01

An analytical model for a dual-material control-gate (DMCG) tunnel field effect transistor (TFET) is presented for the first time in this paper, and the influence of the mobile charges on the potential profile is taken into account. On the basis of the potential profile, the lateral electric field is derived and the expression for the drain current is obtained by integrating the band-to-band tunneling (BTBT) generation rate applicable to low-bandgap and high-bandgap materials over the tunneling region. The model also predicts the impacts of the control-gate work function on the potential and drain current. The advantage of this work is that it not only offers physical insight into device physics but also provides the basic designing guideline for DMCG TFETs, enabling the designer to optimize the device in terms of the on-state current, the on-off current ratio, and suppressed ambipolar behavior. Very good agreements for both the potential and drain current are observed between the model calculations and the simulated results.

Observations on the structural degradation of silver during simultaneous exposure to oxidizing and reducing environments

NASA Astrophysics Data System (ADS)

Singh, Prabhakar; Yang, Zhenguo; Viswanathan, Vish; Stevenson, Jeff W.

2004-06-01

The structural stability of silver (Ag) in dual atmosphere exposure conditions, which are representative of solid oxide fuel cell (SOFC) current collector and gas seals, has been examined in the 600 800 °C temperature range. Experiments conducted on Ag tubular sections exposed to flowing H2-3% H2O (inside the tube) and air (outside the tube) showed extensive porosity formation along the grain boundaries in the bulk metal. Similar tubular sections, when exposed to air only (both inside and outside the tube), showed no bulk porosity or structural changes. It is postulated that the porosity formation in the bulk metal is related to the formation of gaseous H2O bubbles due to simultaneous diffusion of hydrogen and oxygen followed by subsequent interaction resulting in the formation of steam. Thermochemical processes that are responsible for structural degradation are presented and discussed. Based on experimental observations, it is concluded that Ag metal may not provide adequate long-term structural stability under a dual-environment condition that is typical of interconnects or gas seals in intermediate temperature SOFCs.

Motivation to comply with task rules and multitasking performance: The role of need for cognitive closure and goal importance.

PubMed

Szumowska, Ewa; Kossowska, Małgorzata; Roets, Arne

2018-01-01

In three studies, we examined the role task rules play in multitasking performance. We postulated that rules should be especially important for individuals highly motivated to have structure and clear answers, i.e., those high on need for cognitive closure (NFC). High NFC should thus be related to greater compliance with task rules. Specifically, given high goal importance, NFC should be more strongly related to a multitasking strategy when multitasking is imposed by the rules, and to a mono-tasking strategy when monotasking is imposed by the rules. This should translate into better multitasking or mono-tasking performance, depending on condition. Overall, the results were supportive as NFC was related to a more mono-tasking strategy in the mono-tasking condition (Studies 1 and 2 only) and more dual-tasking strategy in the dual-tasking condition (Studies 1-3). This translated into respective differences in performance. The effects were significant only when goal importance was high (Study 1) and held when cognitive ability was controlled for (Study 2).

Synovial fluid hyaluronan mediates MSC attachment to cartilage, a potential novel mechanism contributing to cartilage repair in osteoarthritis using knee joint distraction

PubMed Central

Mastbergen, Simon C; Jones, Elena; Calder, Stuart J; Lafeber, Floris P J G; McGonagle, Dennis

2016-01-01

Objectives Knee joint distraction (KJD) is a novel, but poorly understood, treatment for osteoarthritis (OA) associated with remarkable ‘spontaneous’ cartilage repair in which resident synovial fluid (SF) multipotential mesenchymal stromal cells (MSCs) may play a role. We hypothesised that SF hyaluronic acid (HA) inhibited the initial interaction between MSCs and cartilage, a key first step to integration, and postulate that KJD environment favoured MSC/cartilage interactions. Methods Attachment of dual-labelled SF-MSCs were assessed in a novel in vitro human cartilage model using OA and rheumatoid arthritic (RA) SF. SF was digested with hyaluronidase (hyase) and its effect on adhesion was observed using confocal microscopy. MRI and microscopy were used to image autologous dual-labelled MSCs in an in vivo canine model of KJD. SF-HA was investigated using gel electrophoresis and densitometry. Results Osteoarthritic-synovial fluid (OA-SF) and purified high molecular weight (MW) HA inhibited SF-MSC adhesion to plastic, while hyase treatment of OA-SF but not RA-SF significantly increased MSC adhesion to cartilage (3.7-fold, p<0.05) These differences were linked to the SF mediated HA-coat which was larger in OA-SF than in RA-SF. OA-SF contained >9 MDa HA and this correlated with increases in adhesion (r=0.880). In the canine KJD model, MSC adhesion to cartilage was evident and also dependent on HA MW. Conclusions These findings highlight an unappreciated role of SF-HA on MSC interactions and provide proof of concept that endogenous SF-MSCs are capable of adhering to cartilage in a favourable biochemical and biomechanical environment in OA distracted joints, offering novel one-stage strategies towards joint repair. PMID:25948596

Dual use of electronic and tobacco cigarettes among adolescents: a cross-sectional study in Poland.

PubMed

Goniewicz, Maciej L; Leigh, Noel J; Gawron, Michal; Nadolska, Justyna; Balwicki, Lukasz; McGuire, Connor; Sobczak, Andrzej

2016-03-01

Electronic cigarettes (e-cigarettes) are gaining in popularity among youth. While these products may be beneficial in adult smokers, the effect on young users of electronic and tobacco cigarettes (dual users) is unknown. The objective of this study was to assess the frequency of dual use among adolescents and to compare tobacco cigarette consumption among dual and exclusive tobacco cigarette users. A cross-sectional survey of a sample of 2213 Polish students aged 16-18 conducted between December 2013 and February 2014. Overall, 21.8 % of students were dual users. Dual users were more likely to smoke tobacco cigarettes on a daily basis [adjusted odds ratio, AOR 3.54 (95 % CI 2.34-5.36) and less likely to smoke fewer cigarettes per day (AOR 0.27 (95 % CI 0.12-0.57)] than exclusive tobacco cigarette users. The frequency of dual use was higher than exclusive use of a single product among Polish adolescents. Young dual users do not smoke a lower number of tobacco cigarettes per day than exclusive tobacco cigarette users.

Radiological operational scenario for a permanent lunar base

NASA Astrophysics Data System (ADS)

McCormack, Percival D.

An operational scenario for a lunar base is postulated based on 30 lunar base personnel and 2 year tours of duty plus stipulated numbers of EVA's and sorties in the lunar rover vehicles. It is also postulated that the main shielding material for the lunar base units (habitats, laboratories, etc.) will be lunar regolith. Using the solar minimum period as the basis, total accumulated dose equivalents for the galactic cosmic radiation over the two year period are computed at various shielding depths. Depths of regolith of over 20 g/sq cm are sufficient to reduce the total dose equivalents to well under the present limits. The second arm of the radiological health strategy -- continuous and all-encompassing radiation dosimetry -- is also discussed in some detail. It is also emphasized that monitoring of the base personnel for genetic mutations and chromosomal aberrations must be part of the radiological health program in the lunar base.

Neural Correlates of Confidence during Item Recognition and Source Memory Retrieval: Evidence for Both Dual-Process and Strength Memory Theories

ERIC Educational Resources Information Center

Hayes, Scott M.; Buchler, Norbou; Stokes, Jared; Kragel, James; Cabeza, Roberto

2011-01-01

Although the medial-temporal lobes (MTL), PFC, and parietal cortex are considered primary nodes in the episodic memory network, there is much debate regarding the contributions of MTL, PFC, and parietal subregions to recollection versus familiarity (dual-process theory) and the feasibility of accounts on the basis of a single memory strength…

Comparison of in-vivo failure of single-thread and dual-thread temporary anchorage devices over 18 months: A split-mouth randomized controlled trial.

PubMed

Durrani, Owais Khalid; Shaheed, Sohrab; Khan, Arsalan; Bashir, Ulfat

2017-10-01

The purpose of this study was to compare the in-vivo failure rates of single-thread and dual-thread temporary anchorage device (TAD) designs over 18 months. Thirty patients with skeletal Class II Division 1 malocclusion requiring anchorage from TADs for retraction of maxillary incisors into the extracted premolar space were recruited in this parallel group, split-mouth, randomized controlled trial. A block randomization sequence was generated with Random Allocation Software (version 2.0; Isfahan, Iran) with the allocations concealed in sequentially numbered, opaque, sealed envelopes. A total of 60 TADs (diameter, 2 mm; length, 10 mm) were placed in the maxillary arches of these patients with random allocation of the 2 types to the left and the right sides in a 1:1 ratio. All TADs were placed between the roots of the second premolar and the first molar and were immediately loaded. Patients were followed for a minimum of 12 months and a maximum of 18 months for the failure of the TADs. Data were analyzed blindly on an intention-to-treat basis. Four TADs (13.3%) failed in the single-thread group, and 6 TADs (20%) failed in the dual-thread group. The McNemar test showed an insignificant difference (P = 0.72) between the 2 groups. An odds ratio of 1.6 (95% confidence interval, 0.39-6.97) showed no significant associations among the variables. Most TADs failed in the first month after insertion (50%). The failure rate of dual-thread TADs compared with single-thread TADs is statistically insignificant when placed in the maxilla for retraction of the anterior segment. Registration: The trial was not registered before commencement. The protocol was not published before the trial. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Aging Couples in Dual-Career/Earner Families.

PubMed

Reeves, Joy B; Darville, Ray L

1992-01-01

The authors present results of an empirical study of 611 mature couples in a dual-career or dual-earner famil where at least one spouse is a member of The National Retired Teacher's Association and is retired. We hypothesize that degree of role-sharing will va among mature couples in this special population on the basis of sexcted personal and social characteristics. Through discriminant analysis we identify which personal and social variables best predict whether or not couples currently share roles. We also determine the change in role-sharing over time for these couples. Our hypothesis is confirmed.

Molecular Clues to Physiological and Premature Ageing Revealed | Center for Cancer Research

Cancer.gov

There are many theories about the molecular basis of ageing. One of the most popular ones postulates that organisms age by accumulating damage to their tissues, cells, and molecules. On the cellular level, ageing is associated with progressive changes in chromatin (a combination of DNA and proteins that makes up chromosomes). These changes include loss of chromatin structure, loss and/or modification of essential proteins, and accumulation of DNA damage.

A Theoretical Basis for the Scaling Law of Broadband Shock Noise Intensity in Supersonic Jets

NASA Technical Reports Server (NTRS)

Kandula, Max

2011-01-01

A theoretical basis for the scaling of broadband shock noise intensity In supersonic jets was formulated considering linear shock-shear wave interaction. Modeling of broadband shock noise with the aid of shock-turbulence interaction with special reference to linear theories is briefly reviewed. An hypothesis has been postulated that the peak angle of incidence (closer to the critical angle) for the shear wave primarily governs the generation of sound in the interaction process with the noise generation contribution from off-peak incident angles being relatively unimportant. The proposed hypothesis satisfactorily explains the well-known scaling law for the broadband shock-associated noise in supersonic jets.

Attitudes as Object-Evaluation Associations of Varying Strength

PubMed Central

Fazio, Russell H.

2009-01-01

Historical developments regarding the attitude concept are reviewed, and set the stage for consideration of a theoretical perspective that views attitude, not as a hypothetical construct, but as evaluative knowledge. A model of attitudes as object-evaluation associations of varying strength is summarized, along with research supporting the model’s contention that at least some attitudes are represented in memory and activated automatically upon the individual’s encountering the attitude object. The implications of the theoretical perspective for a number of recent discussions related to the attitude concept are elaborated. Among these issues are the notion of attitudes as “constructions,” the presumed malleability of automatically-activated attitudes, correspondence between implicit and explicit measures of attitude, and postulated dual or multiple attitudes. PMID:19424447

Procedure times, complication rates, and survival times associated with single-chamber versus dual-chamber pacemaker implantation in dogs with clinical signs of bradyarrhythmia: 54 cases (2004-2009).

PubMed

Genovese, David W; Estrada, Amara H; Maisenbacher, Herbert W; Heatwole, Bonnie A; Powell, Melanie A

2013-01-15

To compare procedure times and major and minor complication rates associated with single-chamber versus dual-chamber pacemaker implantation and with 1-lead, 2-lead, and 3-lead pacemaker implantation in dogs with clinical signs of bradyarrhythmia. Retrospective case series. 54 dogs that underwent pacemaker implantation because of clinical signs of bradyarrhythmia. Medical records of dogs that received pacemakers between July 2004 and December 2009 were reviewed for information regarding signalment, diagnosis, pacemaker implantation, pacemaker type, complications, and survival time. Analyses were performed to determine significant differences in anesthesia time, procedure time, and outcome for dogs on the basis of pacing mode and number of pacing leads. 28 of 54 (51.9%) dogs received single-chamber pacemakers and 26 (48.1%) received dual-chamber pacemakers. Mean ± SD procedural time was significantly longer for patients with dual-chamber pacemakers (133.5 ± 51.3 minutes) than for patients with single-chamber pacemakers (94.9 ± 37.0 minutes), and procedure time increased significantly as the number of leads increased (1 lead, 102.3 ± 51.1 minutes; 2 leads, 114.9 ± 24.8 minutes; 3 leads, 158.2 ± 8.5 minutes). Rates of major and minor complications were not significantly different between dogs that received single-chamber pacemakers and those that received dual-chamber pacemakers or among dogs grouped on the basis of the number of pacing leads placed. Although dual-chamber pacemaker implantation did result in increased procedural and anesthesia times, compared with single-chamber pacemaker implantation, this did not result in a higher complication rate.

Management traceability information system for the food supply chain

NASA Astrophysics Data System (ADS)

Bendriss, S.; Benabdelhafid, A.; Boukachour, J.

2008-06-01

For a long time, the traceability was applied only for management reasons, but with the advent of new communication and information technologies more and more used in the logistic medium, the notion of the traceability became new extensive to meet the new market needs in term of information by ensuring accessibility the data characteristic or been dependent on the product throughout its life cycle. On the basis of this postulate, we tried to raise some questions of research, beginning by the presentation of the progress achieved, assumptions and objective relating to the traceability, in the second time we mentioned principal work by showing how evolved the scientific question especially the information systems integrating the traceability were developed very little in the literature. Based on what was developed in the first part, we present our generic modeling approach of communicating product "smart object", able to take into account the various essential elements for its traceability: the product in its various states, various operations carried out on the product, resources used, its localization, and interactions between the product and its environment carried out on the basis of whole of service. In order to validate our generic modeling, a case of study representing an application in a context of food industry is presented.

The Stochastic Early Reaction, Inhibition, and late Action (SERIA) model for antisaccades

PubMed Central

2017-01-01

The antisaccade task is a classic paradigm used to study the voluntary control of eye movements. It requires participants to suppress a reactive eye movement to a visual target and to concurrently initiate a saccade in the opposite direction. Although several models have been proposed to explain error rates and reaction times in this task, no formal model comparison has yet been performed. Here, we describe a Bayesian modeling approach to the antisaccade task that allows us to formally compare different models on the basis of their evidence. First, we provide a formal likelihood function of actions (pro- and antisaccades) and reaction times based on previously published models. Second, we introduce the Stochastic Early Reaction, Inhibition, and late Action model (SERIA), a novel model postulating two different mechanisms that interact in the antisaccade task: an early GO/NO-GO race decision process and a late GO/GO decision process. Third, we apply these models to a data set from an experiment with three mixed blocks of pro- and antisaccade trials. Bayesian model comparison demonstrates that the SERIA model explains the data better than competing models that do not incorporate a late decision process. Moreover, we show that the early decision process postulated by the SERIA model is, to a large extent, insensitive to the cue presented in a single trial. Finally, we use parameter estimates to demonstrate that changes in reaction time and error rate due to the probability of a trial type (pro- or antisaccade) are best explained by faster or slower inhibition and the probability of generating late voluntary prosaccades. PMID:28767650

Modeling of aircraft unsteady aerodynamic characteristics. Part 1: Postulated models

NASA Technical Reports Server (NTRS)

Klein, Vladislav; Noderer, Keith D.

1994-01-01

A short theoretical study of aircraft aerodynamic model equations with unsteady effects is presented. The aerodynamic forces and moments are expressed in terms of indicial functions or internal state variables. The first representation leads to aircraft integro-differential equations of motion; the second preserves the state-space form of the model equations. The formulations of unsteady aerodynamics is applied in two examples. The first example deals with a one-degree-of-freedom harmonic motion about one of the aircraft body axes. In the second example, the equations for longitudinal short-period motion are developed. In these examples, only linear aerodynamic terms are considered. The indicial functions are postulated as simple exponentials and the internal state variables are governed by linear, time-invariant, first-order differential equations. It is shown that both approaches to the modeling of unsteady aerodynamics lead to identical models.

Fulfilling Koch's postulates in glycoscience: HCELL, GPS and translational glycobiology.

PubMed

Sackstein, Robert

2016-06-01

Glycoscience-based research that is performed expressly to address medical necessity and improve patient outcomes is called "translational glycobiology". In the 19th century, Robert Koch proposed a set of postulates to rigorously establish causality in microbial pathogenesis, and these postulates can be reshaped to guide knowledge into how naturally-expressed glycoconjugates direct molecular processes critical to human well-being. Studies in the 1990s indicated that E-selectin, an endothelial lectin that binds sialofucosylated carbohydrate determinants, is constitutively expressed on marrow microvessels, and investigations in my laboratory indicated that human hematopoietic stem cells (HSCs) uniquely express high levels of a specialized glycoform of CD44 called "hematopoietic cell E-/L-selectin ligand" (HCELL) that functions as a highly potent E-selectin ligand. To assess the role of HCELL in directing HSC migration to marrow, a method called "glycosyltransferase-programmed stereosubstitution" (GPS) was developed to custom-modify CD44 glycans to enforce HCELL expression on viable cell surfaces. Human mesenchymal stem cells (MSCs) are devoid of E-selectin ligands, but GPS-based glycoengineering of CD44 on MSCs licenses homing of these cells to marrow in vivo, providing direct evidence that HCELL serves as a "bone marrow homing receptor". This review will discuss the molecular basis of cell migration in historical context, will describe the discovery of HCELL and its function as the bone marrow homing receptor, and will inform on how glycoengineering of CD44 serves as a model for adapting Koch's postulates to elucidate the key roles that glycoconjugates play in human biology and for realizing the immense impact of translational glycobiology in clinical medicine. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Wellbeing of Army Personnel in Dual Military Marriages

DTIC Science & Technology

2015-11-01

my pregnant wife, you know, she didn’t have anybody. It was her first kid , our first kid , and nobody paid me to have to watch my son being born over...set and further examined the role that sex has in dual-military marriages, with a focus on career intentions. I predicted that not only is gender...collected thus far: Table 4. Demographic data Married: Dual-Military Married: Not Dual Military N 276 673 Sex Male: 52% Female: 48

(Un)Intended Consequences: The First-Year College Experience of Female Students with Dual Credits

ERIC Educational Resources Information Center

Tobolowsky, Barbara F.; Allen, Taryn Ozuna

2016-01-01

Using Merton's (1957) anticipatory socialization theory, this qualitative study explored how participation in dual credit in high school helped introduce 12 female students to the academic and social aspects of college to ease their first-year transitions. These students, who entered one Texas university with between 15 and 78 dual credits,…

Third quantization

NASA Astrophysics Data System (ADS)

Seligman, Thomas H.; Prosen, Tomaž

2010-12-01

The basic ideas of second quantization and Fock space are extended to density operator states, used in treatments of open many-body systems. This can be done for fermions and bosons. While the former only requires the use of a non-orthogonal basis, the latter requires the introduction of a dual set of spaces. In both cases an operator algebra closely resembling the canonical one is developed and used to define the dual sets of bases. We here concentrated on the bosonic case where the unboundedness of the operators requires the definitions of dual spaces to support the pair of bases. Some applications, mainly to non-equilibrium steady states, will be mentioned.

Third quantization

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

Seligman, Thomas H.; Centro Internacional de Ciencias, Cuernavaca, Morelos; Prosen, Tomaz

2010-12-23

The basic ideas of second quantization and Fock space are extended to density operator states, used in treatments of open many-body systems. This can be done for fermions and bosons. While the former only requires the use of a non-orthogonal basis, the latter requires the introduction of a dual set of spaces. In both cases an operator algebra closely resembling the canonical one is developed and used to define the dual sets of bases. We here concentrated on the bosonic case where the unboundedness of the operators requires the definitions of dual spaces to support the pair of bases. Somemore » applications, mainly to non-equilibrium steady states, will be mentioned.« less

Application of the dual-kinetic-balance sets in the relativistic many-body problem of atomic structure

NASA Astrophysics Data System (ADS)

Beloy, Kyle; Derevianko, Andrei

2008-09-01

The dual-kinetic-balance (DKB) finite basis set method for solving the Dirac equation for hydrogen-like ions [V.M. Shabaev et al., Phys. Rev. Lett. 93 (2004) 130405] is extended to problems with a non-local spherically-symmetric Dirac-Hartree-Fock potential. We implement the DKB method using B-spline basis sets and compare its performance with the widely-employed approach of Notre Dame (ND) group [W.R. Johnson, S.A. Blundell, J. Sapirstein, Phys. Rev. A 37 (1988) 307-315]. We compare the performance of the ND and DKB methods by computing various properties of Cs atom: energies, hyperfine integrals, the parity-non-conserving amplitude of the 6s-7s transition, and the second-order many-body correction to the removal energy of the valence electrons. We find that for a comparable size of the basis set the accuracy of both methods is similar for matrix elements accumulated far from the nuclear region. However, for atomic properties determined by small distances, the DKB method outperforms the ND approach. In addition, we present a strategy for optimizing the size of the basis sets by choosing progressively smaller number of basis functions for increasingly higher partial waves. This strategy exploits suppression of contributions of high partial waves to typical many-body correlation corrections.

Dual-Energy CT: Basic Principles, Technical Approaches, and Applications in Musculoskeletal Imaging (Part 1).

PubMed

Omoumi, Patrick; Becce, Fabio; Racine, Damien; Ott, Julien G; Andreisek, Gustav; Verdun, Francis R

2015-12-01

In recent years, technological advances have allowed manufacturers to implement dual-energy computed tomography (DECT) on clinical scanners. With its unique ability to differentiate basis materials by their atomic number, DECT has opened new perspectives in imaging. DECT has been used successfully in musculoskeletal imaging with applications ranging from detection, characterization, and quantification of crystal and iron deposits; to simulation of noncalcium (improving the visualization of bone marrow lesions) or noniodine images. Furthermore, the data acquired with DECT can be postprocessed to generate monoenergetic images of varying kiloelectron volts, providing new methods for image contrast optimization as well as metal artifact reduction. The first part of this article reviews the basic principles and technical aspects of DECT including radiation dose considerations. The second part focuses on applications of DECT to musculoskeletal imaging including gout and other crystal-induced arthropathies, virtual noncalcium images for the study of bone marrow lesions, the study of collagenous structures, applications in computed tomography arthrography, as well as the detection of hemosiderin and metal particles. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Dual-Energy CT: Basic Principles, Technical Approaches, and Applications in Musculoskeletal Imaging (Part 2).

PubMed

Omoumi, Patrick; Verdun, Francis R; Guggenberger, Roman; Andreisek, Gustav; Becce, Fabio

2015-12-01

In recent years, technological advances have allowed manufacturers to implement dual-energy computed tomography (DECT) on clinical scanners. With its unique ability to differentiate basis materials by their atomic number, DECT has opened new perspectives in imaging. DECT has been successfully used in musculoskeletal imaging with applications ranging from detection, characterization, and quantification of crystal and iron deposits, to simulation of noncalcium (improving the visualization of bone marrow lesions) or noniodine images. Furthermore, the data acquired with DECT can be postprocessed to generate monoenergetic images of varying kiloelectron volts, providing new methods for image contrast optimization as well as metal artifact reduction. The first part of this article reviews the basic principles and technical aspects of DECT including radiation dose considerations. The second part focuses on applications of DECT to musculoskeletal imaging including gout and other crystal-induced arthropathies, virtual noncalcium images for the study of bone marrow lesions, the study of collagenous structures, applications in computed tomography arthrography, as well as the detection of hemosiderin and metal particles. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

High-pressure processing of apple juice: kinetics of pectin methyl esterase inactivation.

PubMed

Riahi, Esmaeil; Ramaswamy, Hosahalli S

2003-01-01

High-pressure (HP) inactivation kinetics of pectin methyl esterase (PME) in apple juice were evaluated. Commercial PME was dispensed in clarified apple juice, sealed in dual peel sterilizable plastic bags, and subjected to different high-pressure processing conditions (200-400 MPa, 0-180 min). Residual enzyme activity was determined by a titration method estimating the rate of free carboxyl group released by the enzyme acting on pectin substrate at pH 7.5 (30 degrees C). The effects of pressure level and pressure holding time on enzyme inactivation were significant (p < 0.05). PME from the microbial source was found to be more resistant (p < 0.05) to pressure inactivation than PME from the orange peel. Almost a full decimal reduction in the activity of commercial PME was achieved by HP treatment at 400 MPa for 25 min. Inactivation kinetics were evaluated on the basis of a dual effect model involving a pressure pulse effect and a first-order rate model, and the pressure sensitivity of rate constants was modeled by using the z-value concept.

Evaluation of dual polarization scattering matrix radar rain backscatter measurements in the X- and Q-bands

NASA Astrophysics Data System (ADS)

Agrawal, A. P.; Carnegie, D. W.; Boerner, W.-M.

This paper presents an evaluation of polarimetric rain backscatter measurements collected with coherent dual polarization radar systems in the X (8.9 GHz) and Q (45GHz) bands, the first being operated in a pulsed mode and the second being a FM-CW system. The polarimetric measurement data consisted for each band of fifty files of time-sequential scattering matrix measurements expressed in terms of a linear (H, V) antenna polarization state basis. The rain backscattering takes place in a rain cell defined by the beam widths and down range distances of 275 ft through 325 ft and the scattering matrices were measured far below the hydrometeoric scattering center decorrelation time so that ensemble averaging of time-sequential scattering matrices may be applied. In the data evaluation great care was taken in determining: (1) polarimetric Doppler velocities associated with the motion of descending oscillating raindrops and/or eddies within the moving swaths of coastal rain showers, and (2) also the properties of the associated co/cross-polarization rain clutter nulls and their distributions on the Poincare polarization sphere.

Rapid, Microwave-Assisted Synthesis of Cubic, Three-Dimensional, Highly Porous MOF-205 for Room Temperature CO2 Fixation via Cyclic Carbonate Synthesis.

PubMed

Babu, Robin; Roshan, Roshith; Kathalikkattil, Amal Cherian; Kim, Dong Woo; Park, Dae-Won

2016-12-14

A dual-porous, three-dimensional, metal-organic framework [Zn 4 O(2,6-NDC)(BTB) 4/3 ] (MOF-205, BET = 4200 m 2 /g) has been synthesized using microwave power as an alternative energy source for the first time, and its catalytic activity has been exploited for CO 2 -epoxide coupling reactions to produce five-membered cyclic carbonates under solvent-free conditions. Microwave synthesis was performed at different time intervals to reveal the formation of the crystals. Significant conversion of various epoxides was obtained at room temperature, with excellent selectivity toward the desired five-membered cyclic carbonates. The importance of the dual porosity and the synergistic effect of quaternary ammonium salts on efficiently catalyzed CO 2 conversion were investigated using various experimental and physicochemical characterization techniques, and the results were compared with those of the solvothermally synthesized MOF-205 sample. On the basis of literature and experimental inferences, a rationalized mechanism mediated by the zinc center of MOF-205 for the CO 2 -epoxide cycloaddition reaction has been proposed.

Seemingly irrational driving behavior model: The effect of habit strength and anticipated affective reactions.

PubMed

Chung, Yi-Shih

2015-09-01

An increasing amount of evidence suggests that aberrant driving behaviors are not entirely rational. On the basis of the dual-process theory, this study postulates that drivers may learn to perform irrational aberrant driving behaviors, and these behaviors could be derived either from a deliberate or an intuitive decision-making approach. Accordingly, a seemingly irrational driving behavior model is proposed; in this model, the theory of planned behavior (TPB) was adopted to represent the deliberate decision-making mechanism, and habit strength was incorporated to reflect the intuitive decision process. A multiple trivariate mediation structure was designed to reflect the process through which driving behaviors are learned. Anticipated affective reactions (AARs) were further included to examine the effect of affect on aberrant driving behaviors. Considering the example of speeding behaviors, this study developed scales and conducted a two-wave survey of students in two departments at a university in Northern Taiwan. The analysis results show that habit strength consists of multiple aspects, and frequency of past behavior cannot be a complete repository for accumulating habit strength. Habit strength appeared to be a crucial mediator between intention antecedents (e.g., attitude) and the intention itself. Including habit strength in the TPB model enhanced the explained variance of speeding intention by 26.7%. In addition, AARs were different from attitudes; particularly, young drivers tended to perform speeding behaviors to reduce negative feelings such as regret. The proposed model provides an effective alternative approach for investigating aberrant driving behaviors; corresponding countermeasures are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Quantitative SERS Detection of Dopamine in Cerebrospinal Fluid by Dual-Recognition-Induced Hot Spot Generation.

PubMed

Zhang, Kun; Liu, Yu; Wang, Yuning; Zhang, Ren; Liu, Jiangang; Wei, Jia; Qian, Hufei; Qian, Kun; Chen, Ruoping; Liu, Baohong

2018-05-09

Reliable profiling of the extracellular dopamine (DA) concentration in the central nervous system is essential for a deep understanding of its biological and pathological functions. However, quantitative determination of this neurotransmitter remains a challenge because of the extremely low concentration of DA in the cerebrospinal fluid (CSF) of patients. Herein, on the basis of the specific recognition of boronate toward diol and N-hydroxysuccinimide ester toward the amine group, a simple and highly sensitive strategy was presented for DA detection by using surface-enhanced Raman scattering (SERS) spectroscopy as a signal readout. This was realized by first immobilizing 3,3'-dithiodipropionic acid di( N-hydroxysuccinimide ester) on gold thin film surfaces to capture DA, followed by introducing 3-mercaptophenylboronic acid (3-MPBA)-functionalized silver nanoparticles to generate numerous plasmonic "hot spots" with the nanoparticle-on-mirror geometry. Such a dual-recognition mechanism not only avoids complicated bioelement-based manipulations but also efficiently decreases the background signal. With the direct use of the recognition probe 3-MPBA as a Raman reporter, the "signal-on" SERS method was employed to quantify the concentration of DA from 1 pM to 1 μM with a detection limit of 0.3 pM. Moreover, our dual-recognition-directed SERS assay exhibited a high resistance to cerebral interference and was successfully applied to monitoring of DA in CSF samples of patients.

Can infections prevent or cure allergy and autoimmunity?

PubMed

Kamradt, Thomas

2005-06-01

Extract: In western countries the prevalence and incidence of allergic and autoimmune diseases have been increasing dramatically over the last 50 years. In the last two decades, significant progress has been made towards understanding the genetic basis for susceptibility to autoimmunity or allergy. Genetic factors, however, cannot explain abrupt changes in disease incidence. It is therefore likely that environmental factors, specifically environmental factors that have changed over the last two generations, are critical for the increasing incidence of allergies and autoimmune diseases. Traditionally, autoimmune diseases such as multiple sclerosis (MS), type I diabetes, or rheumatoid arthritis (RA) are believed to have resulted from aberrant immune response to pathogens. In contrast, the "hygiene hypothesis," first postulated some 20 years ago, proposes that a lack of infections, especially during early childhood, predisposes one to the aberrant immune responses against harmless foreign antigens that cause allergic diseases such as rhinitis, atopic dermatitis, and allergic asthma. Several lines of epidemiological, clinical and experimental research point to more complex connections, either protective or pathogenic, between infection, allergy and autoimmunity.

Calibration of the Galactic Cosmic Ray Flux

NASA Technical Reports Server (NTRS)

Mathew, K. J.; Marti, K.

2004-01-01

We report first Xe data on the cross-calibration of I-129-Xe-129(sub n) ages with conventional CRE ages, a method which is expected to provide information on the long-term constancy of the galactic cosmic ray (GCR) flux. We studied isotopic signatures of Xe released in stepwise heating, decomposition and melting of troilites in the Cape York iron meteorite to identify isotopic shifts in Xe-129 and Xe-131 due to neutron capture in Te-128 and Te-130. We also resolve components due to extinct 129I, spallation and fission Xe. There has recently been much speculation on the constancy of GCR over long time scales, as may be inferred from iron meteorites. If GCRs originate from supernova events, this provides the basis for postulating increased fluxes at locations with higher than average densities of supernovae, specifically in OB-associations. The solar system at present appears to be inside a local bubble between spiral arms and may experience an increased GCR flux.

A Novel Amyloid Designable Scaffold and Potential Inhibitor Inspired by GAIIG of Amyloid Beta and the HIV-1 V3 loop.

PubMed

Kokotidou, C; Jonnalagadda, S V R; Orr, A A; Seoane-Blanco, M; Apostolidou, C P; van Raaij, M J; Kotzabasaki, M; Chatzoudis, A; Jakubowski, J M; Mossou, E; Forsyth, V T; Mitchell, E P; Bowler, M W; Llamas-Saiz, A L; Tamamis, P; Mitraki, A

2018-05-17

The GAIIG sequence, common to the amyloid beta peptide (residues 29-33) and to the HIV gp 120 (residues 24-28 in a typical V3 loop) self-assembles into amyloid fibrils, as suggested by theory and the experiments presented here. The longer YATGAIIGNII sequence from the V3 loop also self-assembles into amyloid fibrils, of which the first three and the last two residues are outside the amyloid GAIIG core. We postulate that this sequence, with suitable selected replacements at the flexible positions, can serve as a designable scaffold for novel amyloid-based materials. Moreover, we report the single X-ray crystal structure of the beta-breaker peptide GAIPIG at 1.05 Å resolution. This structural information could serve as the basis for structure-based design of potential inhibitors of amyloid formation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Central nervous system vasculitis after starting methimazole in a woman with Graves' disease.

PubMed

Tripodi, Pier Francesco; Ruggeri, Rosaria M; Campennì, Alfredo; Cucinotta, Mariapaola; Mirto, Angela; Lo Gullo, Renato; Baldari, Sergio; Trimarchi, Francesco; Cucinotta, Domenico; Russo, Giuseppina T

2008-09-01

Graves' disease (GD), a prototypical autoimmune disorder, is associated with other autoimmune diseases, including vasculitis. Antithyroid drugs, despite their postulated immunosuppressive effects, may cause several autoimmune disorders. Here we describe the first patient with central nervous system (CNS) vasculitis that developed shortly after the start of methimazole (MMI) treatment for GD. CNS vasculitis was suspected on the basis of the clinical features and neurologic examination, showing a reinforcement of deep reflexes, especially of the left knee and Achilles reflexes. The diagnosis was confirmed by a brain magnetic resonance imaging (MRI), which showed some hyperintensive spots in the subcortical substantia alba and in the parietal area bilaterally, and by a single-photon emission computed tomography (SPECT) imaging, which showed a nonhomogenous distribution of the blood flow in the brain, with a reduced perfusion on the left side of the frontotemporal and parietal regions, and on the right side of the frontotemporal area. MMI was stopped before total thyroidectomy, and symptoms resolved in the next 5 weeks. Six months after MMI was stopped, the brain MRI and SPECT had become normal. To our knowledge, this is the first report of CNS vasculitis related to MMI therapy.

Unravelling the distinct strains of Tharu ancestry.

PubMed

Chaubey, Gyaneshwer; Singh, Manvendra; Crivellaro, Federica; Tamang, Rakesh; Nandan, Amrita; Singh, Kamayani; Sharma, Varun Kumar; Pathak, Ajai Kumar; Shah, Anish M; Sharma, Vishwas; Singh, Vipin Kumar; Selvi Rani, Deepa; Rai, Niraj; Kushniarevich, Alena; Ilumäe, Anne-Mai; Karmin, Monika; Phillip, Anand; Verma, Abhilasha; Prank, Erik; Singh, Vijay Kumar; Li, Blaise; Govindaraj, Periyasamy; Chaubey, Akhilesh Kumar; Dubey, Pavan Kumar; Reddy, Alla G; Premkumar, Kumpati; Vishnupriya, Satti; Pande, Veena; Parik, Jüri; Rootsi, Siiri; Endicott, Phillip; Metspalu, Mait; Lahr, Marta Mirazon; van Driem, George; Villems, Richard; Kivisild, Toomas; Singh, Lalji; Thangaraj, Kumarasamy

2014-12-01

The northern region of the Indian subcontinent is a vast landscape interlaced by diverse ecologies, for example, the Gangetic Plain and the Himalayas. A great number of ethnic groups are found there, displaying a multitude of languages and cultures. The Tharu is one of the largest and most linguistically diverse of such groups, scattered across the Tarai region of Nepal and bordering Indian states. Their origins are uncertain. Hypotheses have been advanced postulating shared ancestry with Austroasiatic, or Tibeto-Burman-speaking populations as well as aboriginal roots in the Tarai. Several Tharu groups speak a variety of Indo-Aryan languages, but have traditionally been described by ethnographers as representing East Asian phenotype. Their ancestry and intra-population diversity has previously been tested only for haploid (mitochondrial DNA and Y-chromosome) markers in a small portion of the population. This study presents the first systematic genetic survey of the Tharu from both Nepal and two Indian states of Uttarakhand and Uttar Pradesh, using genome-wide SNPs and haploid markers. We show that the Tharu have dual genetic ancestry as up to one-half of their gene pool is of East Asian origin. Within the South Asian proportion of the Tharu genetic ancestry, we see vestiges of their common origin in the north of the South Asian Subcontinent manifested by mitochondrial DNA haplogroup M43.

Human error identification for laparoscopic surgery: Development of a motion economy perspective.

PubMed

Al-Hakim, Latif; Sevdalis, Nick; Maiping, Tanaphon; Watanachote, Damrongpan; Sengupta, Shomik; Dissaranan, Charuspong

2015-09-01

This study postulates that traditional human error identification techniques fail to consider motion economy principles and, accordingly, their applicability in operating theatres may be limited. This study addresses this gap in the literature with a dual aim. First, it identifies the principles of motion economy that suit the operative environment and second, it develops a new error mode taxonomy for human error identification techniques which recognises motion economy deficiencies affecting the performance of surgeons and predisposing them to errors. A total of 30 principles of motion economy were developed and categorised into five areas. A hierarchical task analysis was used to break down main tasks of a urological laparoscopic surgery (hand-assisted laparoscopic nephrectomy) to their elements and the new taxonomy was used to identify errors and their root causes resulting from violation of motion economy principles. The approach was prospectively tested in 12 observed laparoscopic surgeries performed by 5 experienced surgeons. A total of 86 errors were identified and linked to the motion economy deficiencies. Results indicate the developed methodology is promising. Our methodology allows error prevention in surgery and the developed set of motion economy principles could be useful for training surgeons on motion economy principles. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Alkaline phosphatase: a possible treatment for sepsis-associated acute kidney injury in critically ill patients.

PubMed

Peters, Esther; Heemskerk, Suzanne; Masereeuw, Rosalinde; Pickkers, Peter

2014-06-01

Acute kidney injury (AKI) is a common disease in the intensive care unit and accounts for high morbidity and mortality. Sepsis, the predominant cause of AKI in this setting, involves a complex pathogenesis in which renal inflammation and hypoxia are believed to play an important role. A new therapy should be aimed at targeting both these processes, and the enzyme alkaline phosphatase, with its dual mode of action, might be a promising candidate. First, alkaline phosphatase is able to reduce inflammation through dephosphorylation and thereby detoxification of endotoxin (lipopolysaccharide), which is an important mediator of sepsis. Second, adenosine triphosphate, released during cellular stress caused by inflammation and hypoxia, has detrimental effects but can be converted by alkaline phosphatase into adenosine with anti-inflammatory and tissue-protective effects. These postulated beneficial effects of alkaline phosphatase have been confirmed in animal experiments and two phase 2a clinical trials showing that kidney function improved in critically ill patients with sepsis-associated AKI. Because renal inflammation and hypoxia also are observed commonly in AKI induced by other causes, it would be of interest to investigate the therapeutic effect of alkaline phosphatase in these nephropathies as well. Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Dual Credit Enrollment and GPA by Ethnicity and Gender at Texas 2-Year Colleges

ERIC Educational Resources Information Center

Young, Robert D., Jr.

2013-01-01

Purpose: The purpose of this investigation was to determine the extent to which differences were present in dual credit course enrollment. Specifically examined were whether differences were present in the first semester GPA and at the end of the first two semesters for students who enrolled in dual credit courses while in high school from…

Three-dimensional visualization of gammaherpesvirus life cycle in host cells by electron tomography.

PubMed

Peng, Li; Ryazantsev, Sergey; Sun, Ren; Zhou, Z Hong

2010-01-13

Gammaherpesviruses are etiologically associated with human tumors. A three-dimensional (3D) examination of their life cycle in the host is lacking, significantly limiting our understanding of the structural and molecular basis of virus-host interactions. Here, we report the first 3D visualization of key stages of the murine gammaherpesvirus 68 life cycle in NIH 3T3 cells, including viral attachment, entry, assembly, and egress, by dual-axis electron tomography. In particular, we revealed the transient processes of incoming capsids injecting viral DNA through nuclear pore complexes and nascent DNA being packaged into progeny capsids in vivo as a spool coaxial with the putative portal vertex. We discovered that intranuclear invagination of both nuclear membranes is involved in nuclear egress of herpesvirus capsids. Taken together, our results provide the structural basis for a detailed mechanistic description of gammaherpesvirus life cycle and also demonstrate the advantage of electron tomography in dissecting complex cellular processes of viral infection.

Effective Dual Method Contraceptive Use and HPV Vaccination Among U.S. Adolescent and Young Adult Females

PubMed Central

Vanderpool, Robin C.; Williams, Corrine M.; Klawitter, Amy R.; Eddens, Katherine

2016-01-01

Background Problem Behavior Theory posits that risky behaviors cluster in individuals, implying that protective behaviors may follow a similar pattern. The purpose of this study was to determine whether the protective behavior of effective dual method contraception use at first and most recent sexual intercourse is associated with HPV vaccination among adolescent and young adult females. Methods National Survey of Family Growth (2006–2010) data were used to examine the association between women’s contraception use during first and most recent sexual intercourse and HPV vaccination. Women aged 15 to 24 years (n = 1,820) served as the study sample. Findings At first and last sexual intercourse, effective dual method contraception use was reported by 15.3% and 16.8% women, respectively; 27.8% reported receiving at least one dose of the human papillomavirus (HPV) vaccine. Higher HPV vaccination rates were observed among dual method users at first and last sexual intercourse (36.4% and 48.2%, respectively). This trend was also observed across age groups (15–19 year olds vs. 20–24 year olds). In adjusted models, among all respondents, dual users at last sexual intercourse were significantly more likely to be vaccinated, whereas at first sexual intercourse only younger dual users were more likely to report HPV vaccination. Conclusions Findings suggest that the protective behavior of dual method contraceptive use at first and most recent sexual intercourse may serve as a predictor of another complementary health behavior, HPV vaccination, particularly among adolescent females. More research is needed to understand behavioral clustering to design related multi-focused women’s health interventions. PMID:25213746

Effective dual method contraceptive use and HPV vaccination among U.S. adolescent and young adult females.

PubMed

Vanderpool, Robin C; Williams, Corrine M; Klawitter, Amy R; Eddens, Katherine

2014-01-01

Problem Behavior Theory posits that risky behaviors cluster in individuals, implying that protective behaviors may follow a similar pattern. The purpose of this study was to determine whether the protective behavior of effective dual method contraception use at first and most recent sexual intercourse is associated with HPV vaccination among adolescent and young adult females. National Survey of Family Growth (2006-2010) data were used to examine the association between women's contraception use during first and most recent sexual intercourse and HPV vaccination. Women aged 15 to 24 years (n = 1,820) served as the study sample. At first and last sexual intercourse, effective dual method contraception use was reported by 15.3% and 16.8% women, respectively; 27.8% reported receiving at least one dose of the human papillomavirus (HPV) vaccine. Higher HPV vaccination rates were observed among dual method users at first and last sexual intercourse (36.4% and 48.2%, respectively). This trend was also observed across age groups (15-19 year olds vs. 20-24 year olds). In adjusted models, among all respondents, dual users at last sexual intercourse were significantly more likely to be vaccinated, whereas at first sexual intercourse only younger dual users were more likely to report HPV vaccination. Findings suggest that the protective behavior of dual method contraceptive use at first and most recent sexual intercourse may serve as a predictor of another complementary health behavior, HPV vaccination, particularly among adolescent females. More research is needed to understand behavioral clustering to design related multi-focused women's health interventions. Copyright © 2014 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

Librarians and the First Amendment after Nixon

ERIC Educational Resources Information Center

Hentoff, Nat

1974-01-01

Reviews the state of first amendment freedoms today and postulates their erosion in the near future. Includes discussions of the balanced presentation and fairness doctrines, decline of press freedoms, privacy of library circulation records, the Nixon Supreme Court decisions on obscenity, the FCC suppression of broadcasters' freedom of speech,…

Gait disorders in the elderly and dual task gait analysis: a new approach for identifying motor phenotypes.

PubMed

Auvinet, Bernard; Touzard, Claude; Montestruc, François; Delafond, Arnaud; Goeb, Vincent

2017-01-31

Gait disorders and gait analysis under single and dual-task conditions are topics of great interest, but very few studies have looked for the relevance of gait analysis under dual-task conditions in elderly people on the basis of a clinical approach. An observational study including 103 patients (mean age 76.3 ± 7.2, women 56%) suffering from gait disorders or memory impairment was conducted. Gait analysis under dual-task conditions was carried out for all patients. Brain MRI was performed in the absence of contra-indications. Three main gait variables were measured: walking speed, stride frequency, and stride regularity. For each gait variable, the dual task cost was computed and a quartile analysis was obtained. Nonparametric tests were used for all the comparisons (Wilcoxon, Kruskal-Wallis, Fisher or Chi 2 tests). Four clinical subgroups were identified: gait instability (45%), recurrent falls (29%), memory impairment (18%), and cautious gait (8%). The biomechanical severity of these subgroups was ordered according to walking speed and stride regularity under both conditions, from least to most serious as follows: memory impairment, gait instability, recurrent falls, cautious gait (p < 0.01 for walking speed, p = 0.05 for stride regularity). According to the established diagnoses of gait disorders, 5 main pathological subgroups were identified (musculoskeletal diseases (n = 11), vestibular diseases (n = 6), mild cognitive impairment (n = 24), central nervous system pathologies, (n = 51), and without diagnosis (n = 8)). The dual task cost for walking speed, stride frequency and stride regularity were different among these subgroups (p < 0.01). The subgroups mild cognitive impairment and central nervous system pathologies both showed together a higher dual task cost for each variable compared to the other subgroups combined (p = 0.01). The quartile analysis of dual task cost for stride frequency and stride regularity allowed the identification of 3 motor phenotypes (p < 0.01), without any difference for white matter hyperintensities, but with an increased Scheltens score from the first to the third motor phenotype (p = 0.05). Gait analysis under dual-task conditions in elderly people suffering from gait disorders or memory impairment is of great value in assessing the severity of gait disorders, differentiating between peripheral pathologies and central nervous system pathologies, and identifying motor phenotypes. Correlations between motor phenotypes and brain imaging require further studies.

TU-A-12A-08: Computing Longitudinal Material Changes in Bone Metastases Using Dual Energy Computed Tomography

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

Schmidtlein, CR; Hwang, S; Veeraraghavan, H

Purpose: This study demonstrates a methodology for tracking changes in metastatic bone disease using trajectories in material basis space in serial dual energy computed tomography (DECT) studies. Methods: This study includes patients with bone metastases from breast cancer that had clinical surveillance CT scans using a General Electric CT750HD in dual energy mode. A radiologist defined regions-of-interested (ROI) for bone metastasis, normal bone, and marrow across the serial DECT scans. Our approach employs a Radon transform to forward-projection the basis images, namely, water and iodine, into sinogram space. This data is then repartitioned into fat/bone and effective density/Z image pairsmore » using assumed energy spectrums for the x-ray energies. This approach both helps remove negative material densities and avoids adding spectrum-hardening artifacts. These new basis data sets were then reconstructed via filtered back-projection to create new material basis pair images. The trajectories of these pairs were then plotted in the new basis space providing a means to both visualize and quantitatively measure changes in the material properties of the tumors. Results: ROI containing radiologist defined metastatic bone disease showed well-defined trajectories in both fat/bone and effective density/Z space. ROI that contained radiologist defined normal bone and marrow did not exhibit any discernible trajectories and were stable from scan to scan. Conclusions: The preliminary results show that changes in material composition and effective density/Z image pairs were seen primarily in metastasis and not in normal tissue. This study indicates that by using routine clinical DECT it may be possible to monitor therapy response of bone metastases because healing or worsening bone metastases change material composition of bone. Additional studies are needed to further validate these results and to test for their correlation with outcome.« less

Resistance of Bacillus Endospores to Extreme Terrestrial and Extraterrestrial Environments

PubMed Central

Nicholson, Wayne L.; Munakata, Nobuo; Horneck, Gerda; Melosh, Henry J.; Setlow, Peter

2000-01-01

Endospores of Bacillus spp., especially Bacillus subtilis, have served as experimental models for exploring the molecular mechanisms underlying the incredible longevity of spores and their resistance to environmental insults. In this review we summarize the molecular laboratory model of spore resistance mechanisms and attempt to use the model as a basis for exploration of the resistance of spores to environmental extremes both on Earth and during postulated interplanetary transfer through space as a result of natural impact processes. PMID:10974126

A Survey of Long-Range Forecasting Models and Data Resources: A Method for Their Application at the Department of Defense.

DTIC Science & Technology

1979-08-08

confident analysis or prediction. Still, the behavioralist models do provide a basis for comparison and analysis of real world environments . In addition...p.236. 60 o Environmental - the lowest level and encompasses man’s physical environment (climate, land, water, air, and physical resources); also... analysis . The food model report is based on two postulates: a. It is reasonable to review agriculture in an ecosystems framework *Mesarovic, M., and Pestel

[AVIATION MEDICINE: THEORETICAL CONCEPTS AND FOCAL FUNDAMENTAL AND PRACTICAL ISSUES (for the 80th anniversary of the Research Test Center of Aerospace Medicine and Military Ergonomics)].

PubMed

Zhdanko, I M; Pisarev, A A; Vorona, A A; Lapa, V V; Khomenko, M N

2015-01-01

The article discloses postulates of theoretical concepts that make the methodological basis for addressing the real-world aviation medicine challenges of humanizing aviator's environment, labor content and means, and health and performance maintenance. Under consideration are focal fundamental and practical issues arising with the technological progress in aviation and dealt with at the AF CRI Research Test Center of Aerospace Medicine and Military Ergonomics.

ψ -ontology result without the Cartesian product assumption

NASA Astrophysics Data System (ADS)

Myrvold, Wayne C.

2018-05-01

We introduce a weakening of the preparation independence postulate of Pusey et al. [Nat. Phys. 8, 475 (2012), 10.1038/nphys2309] that does not presuppose that the space of ontic states resulting from a product-state preparation can be represented by the Cartesian product of subsystem state spaces. On the basis of this weakened assumption, it is shown that, in any model that reproduces the quantum probabilities, any pair of pure quantum states |ψ >,|ϕ > with <ϕ |ψ > ≤1 /√{2 } must be ontologically distinct.

Isogeometric Bézier dual mortaring: Refineable higher-order spline dual bases and weakly continuous geometry

NASA Astrophysics Data System (ADS)

Zou, Z.; Scott, M. A.; Borden, M. J.; Thomas, D. C.; Dornisch, W.; Brivadis, E.

2018-05-01

In this paper we develop the isogeometric B\\'ezier dual mortar method. It is based on B\\'ezier extraction and projection and is applicable to any spline space which can be represented in B\\'ezier form (i.e., NURBS, T-splines, LR-splines, etc.). The approach weakly enforces the continuity of the solution at patch interfaces and the error can be adaptively controlled by leveraging the refineability of the underlying dual spline basis without introducing any additional degrees of freedom. We also develop weakly continuous geometry as a particular application of isogeometric B\\'ezier dual mortaring. Weakly continuous geometry is a geometry description where the weak continuity constraints are built into properly modified B\\'ezier extraction operators. As a result, multi-patch models can be processed in a solver directly without having to employ a mortaring solution strategy. We demonstrate the utility of the approach on several challenging benchmark problems. Keywords: Mortar methods, Isogeometric analysis, B\\'ezier extraction, B\\'ezier projection

Analysis of the interaction between experimental and applied behavior analysis.

PubMed

Virues-Ortega, Javier; Hurtado-Parrado, Camilo; Cox, Alison D; Pear, Joseph J

2014-01-01

To study the influences between basic and applied research in behavior analysis, we analyzed the coauthorship interactions of authors who published in JABA and JEAB from 1980 to 2010. We paid particular attention to authors who published in both JABA and JEAB (dual authors) as potential agents of cross-field interactions. We present a comprehensive analysis of dual authors' coauthorship interactions using social networks methodology and key word analysis. The number of dual authors more than doubled (26 to 67) and their productivity tripled (7% to 26% of JABA and JEAB articles) between 1980 and 2010. Dual authors stood out in terms of number of collaborators, number of publications, and ability to interact with multiple groups within the field. The steady increase in JEAB and JABA interactions through coauthors and the increasing range of topics covered by dual authors provide a basis for optimism regarding the progressive integration of basic and applied behavior analysis. © Society for the Experimental Analysis of Behavior.

Bone density in patients with chondromalacia patella.

PubMed

Salehi, Iraj; Khazaeli, Shabnam; Hatami, Parta; Malekpour, Mahdi

2010-06-01

Chondromalacia of the patella is the most common cause of anterior knee pain in young women. The etiology of the disease is not well-understood but the initial lesion is a disorganization of collagenous structures. Since the disease is proposed to be due to generalized constitutional disturbance, we postulated that bony structures could also be involved. To investigate this hypothesis we measured the bone density of 286 patients with the diagnosis of chondromalacia of the patella during a 4-year period using dual energy X-ray absorptiometry (DXA) method. We found a significant number of patients having low bone densities. This problem was more pronounced in men and in younger age groups. We suggest base-line bone density evaluation in all patients, treatment of osteopenia or osteoporosis in select patients and regular follow-ups using DXA.

Re-discovering periodontal butyric acid: New insights on an old metabolite.

PubMed

Cueno, Marni E; Ochiai, Kuniyasu

2016-05-01

The oral microbiome is composed of detrimental and beneficial microbial communities producing several microbial factors that could contribute to the development of the oral microbiome and, likewise, may lead to the development of host diseases. Metabolites, like short-chain fatty acids, are commonly produced by the oral microbiome and serve various functions. Among the periodontal short-chain fatty acids, butyric acid is mainly produced by periodontopathic bacteria and, attributable to the butyrate paradox, is postulated to exhibit a dual function depending on butyric acid concentration. A better understanding of the interconnecting networks that would influence butyric acid function in the oral cavity may shed a new light on the current existing knowledge and view regarding butyric acid. Copyright © 2015 Elsevier Ltd. All rights reserved.

IS ISLAND PARK A HOT DRY ROCK SYSTEM?

USGS Publications Warehouse

Hoover, D.B.; Pierce, Herbert A.; Long, C.L.

1985-01-01

The Island Park-Yellowstone National Park region comprises a complex caldera system which has formed over the last 2 m. y. The caldera system has been estimated to contain 50% of the total thermal energy remaining in all young igneous systems in the United States. As the result of a reexamination of the data and recent electrical work in the area, the authors now postulate that much of the area where the first- and second-stage calderas developed is underlain by a solidified but still hot pluton. They postulate that the pluton represents a significant hot-dry-rock resource for the United States.

The Measurement Process in the Generalized Contexts Formalism for Quantum Histories

NASA Astrophysics Data System (ADS)

Losada, Marcelo; Vanni, Leonardo; Laura, Roberto

2016-02-01

In the interpretations of quantum mechanics involving quantum histories there is no collapse postulate and the measurement is considered as a quantum interaction between the measured system and the measured instrument. For two consecutive non ideal measurements on the same system, we prove that both pointer indications at the end of each measurement are compatible properties in our generalized context formalism for quantum histories. Inmediately after the first measurement an effective state for the measured system is deduced from the formalism, generalizing the state that would be obtained by applying the state collapse postulate.

Dynamical Correspondence in a Generalized Quantum Theory

NASA Astrophysics Data System (ADS)

Niestegge, Gerd

2015-05-01

In order to figure out why quantum physics needs the complex Hilbert space, many attempts have been made to distinguish the C*-algebras and von Neumann algebras in more general classes of abstractly defined Jordan algebras (JB- and JBW-algebras). One particularly important distinguishing property was identified by Alfsen and Shultz and is the existence of a dynamical correspondence. It reproduces the dual role of the selfadjoint operators as observables and generators of dynamical groups in quantum mechanics. In the paper, this concept is extended to another class of nonassociative algebras, arising from recent studies of the quantum logics with a conditional probability calculus and particularly of those that rule out third-order interference. The conditional probability calculus is a mathematical model of the Lüders-von Neumann quantum measurement process, and third-order interference is a property of the conditional probabilities which was discovered by Sorkin (Mod Phys Lett A 9:3119-3127, 1994) and which is ruled out by quantum mechanics. It is shown then that the postulates that a dynamical correspondence exists and that the square of any algebra element is positive still characterize, in the class considered, those algebras that emerge from the selfadjoint parts of C*-algebras equipped with the Jordan product. Within this class, the two postulates thus result in ordinary quantum mechanics using the complex Hilbert space or, vice versa, a genuine generalization of quantum theory must omit at least one of them.

Method for ambiguity resolution in range-Doppler measurements

NASA Technical Reports Server (NTRS)

Heymsfield, Gerald M. (Inventor); Miller, Lee S. (Inventor)

1994-01-01

A method for resolving range and Doppler target ambiguities when the target has substantial range or has a high relative velocity in which a first signal is generated and a second signal is also generated which is coherent with the first signal but at a slightly different frequency such that there exists a difference in frequency between these two signals of Delta f(sub t). The first and second signals are converted into a dual-frequency pulsed signal, amplified, and the dual-frequency pulsed signal is transmitted towards a target. A reflected dual-frequency signal is received from the target, amplified, and changed to an intermediate dual-frequency signal. The intermediate dual-frequency signal is amplified, with extracting of a shifted difference frequency Delta f(sub r) from the amplified intermediate dual-frequency signal done by a nonlinear detector. The final step is generating two quadrature signals from the difference frequency Delta f(sub t) and the shifted difference frequency Delta f(sub r) and processing the two quadrature signals to determine range and Doppler information of the target.

TU-F-18A-06: Dual Energy CT Using One Full Scan and a Second Scan with Very Few Projections

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

Wang, T; Zhu, L

Purpose: The conventional dual energy CT (DECT) requires two full CT scans at different energy levels, resulting in dose increase as well as imaging errors from patient motion between the two scans. To shorten the scan time of DECT and thus overcome these drawbacks, we propose a new DECT algorithm using one full scan and a second scan with very few projections by preserving structural information. Methods: We first reconstruct a CT image on the full scan using a standard filtered-backprojection (FBP) algorithm. We then use a compressed sensing (CS) based iterative algorithm on the second scan for reconstruction frommore » very few projections. The edges extracted from the first scan are used as weights in the Objectives: function of the CS-based reconstruction to substantially improve the image quality of CT reconstruction. The basis material images are then obtained by an iterative image-domain decomposition method and an electron density map is finally calculated. The proposed method is evaluated on phantoms. Results: On the Catphan 600 phantom, the CT reconstruction mean error using the proposed method on 20 and 5 projections are 4.76% and 5.02%, respectively. Compared with conventional iterative reconstruction, the proposed edge weighting preserves object structures and achieves a better spatial resolution. With basis materials of Iodine and Teflon, our method on 20 projections obtains similar quality of decomposed material images compared with FBP on a full scan and the mean error of electron density in the selected regions of interest is 0.29%. Conclusion: We propose an effective method for reducing projections and therefore scan time in DECT. We show that a full scan plus a 20-projection scan are sufficient to provide DECT images and electron density with similar quality compared with two full scans. Our future work includes more phantom studies to validate the performance of our method.« less

Profiling the SO2 Plume from Volcan Turrialba: Ticosonde Balloon Measurements Compared with OMI and OMPS Retrievals

NASA Astrophysics Data System (ADS)

Selkirk, H. B.; Krotkov, N. A.; Li, C.; Morris, G.; Diaz, J. A.; Carn, S. A.; Voemel, H.; Nord, P. M.; Larson, K.

2014-12-01

The summit of Volcan Turrialba (elev. 3340 m) lies less than 50 km upstream in the prevailing easterlies from the Ticosonde balloon launch site at San Jose, Costa Rica, where ECC ozone sondes have been launched regularly since 2005. In 2006 we began to see telltale notches in the ozone profiles in the altitude range between 2 and 6 km. Given the proximity of Turrialba, it seemed likely that SO2 in the volcano's plume was interfering in the chemical reaction in the ECC ozone sonde used to detect ozone. In early 2010, fumarolic activity in the Turrialba crater increased strongly, and the profile notches in our soundings increased in frequency as well, consistent with this hypothesis. In February 2012 we tested a dual ECC sonde system, where an additional sonde is flown on the same payload using a selective SO2 filter. The difference of the measurements in the dual sonde is a direct measure of the amount of SO2 encountered. This first dual sonde passed through the plume, and the data indicated a tropospheric SO2 column of 1.4 DU, comparing favorably with a total column of 1.7 DU in the OMI 3-km linear fit (LF) product at the sonde profile location and at nearly the same time. We are now launching dual sondes on a regular basis with 18 launches in the first 12 months through July 2014; 11 of these have detectable SO2 signals. These soundings have great potential for validation of the Aura OMI and the Suomi-NPP OMPS retrievals of SO2. Here we present the sonde measurements and compare them with two satellite datasets: the Aura OMI Linear Fit (LF) product and the Suomi-NPP OMPS Principal Components Analysis (PCA) boundary layer product. The PCA algorithm reduces retrieval noise and artifacts by more accurately accounting for various interferences in SO2 retrievals such as O3 absorption and rotational Raman scattering. The comparisons with the in situ observations indicate a significant improvement of the PCA algorithm in capturing relatively weak volcanic SO2 signals.

Profiling the SO2 Plume from Volcan Turrialba: Ticosonde Balloon Measurements Compared with OMI and OMPS Retrievals

NASA Technical Reports Server (NTRS)

Selkirk, Henry; Krotkov, Nickolay; Li, Can; Morris, Gary (Inventor); Diaz, Jorge Andres; Carn, Simon; Vomel, Holger; Corrales, Ernesto; Nord, Paul; Larson, Kelsey

2014-01-01

The summit of Volcan Turrialba (elev. 3340 m) lies less than 50 km upstream in the prevailing easterlies from the Ticosonde balloon launch site at San Jose, Costa Rica, where ECC ozone sondes have been launched regularly since 2005. In 2006 we began to see telltale notches in the ozone profiles in the altitude range between 2 and 6 km. Given the proximity of Turrialba, it seemed likely that SO2 in the volcano's plume was interfering in the chemical reaction in the ECC ozone sonde used to detect ozone. In early 2010, fumarolic activity in the Turrialba crater increased strongly, and the profile notches in our soundings increased in frequency as well, consistent with this hypothesis. In February 2012 we tested a dual ECC sonde system, where an additional sonde is flown on the same payload using a selective SO2 filter. The difference of the measurements in the dual sonde is a direct measure of the amount of SO2 encountered. This first dual sonde passed through the plume, and the data indicated a tropospheric SO2 column of 1.4 DU, comparing favorably with a total column of 1.7 DU in the OMI 3-km linear fit (LF) product at the sonde profile location and at nearly the same time. We are now launching dual sondes on a regular basis with 18 launches in the first 12 months through July 2014; 11 of these have detectable SO2 signals. These soundings have great potential for validation of the Aura OMI and the Suomi-NPP OMPS retrievals of SO2. Here we present the sonde measurements and compare them with two satellite datasets: the Aura OMI Linear Fit (LF) product and the Suomi-NPP OMPS Principal Components Analysis (PCA) boundary layer product. The PCA algorithm reduces retrieval noise and artifacts by more accurately accounting for various interferences in SO2 retrievals such as O3 absorption and rotational Raman scattering. The comparisons with the in situ observations indicate a significant improvement of the PCA algorithm in capturing relatively weak volcanic SO2 signals.

The proteome of exudates from germinating Lupinus albus seeds is secreted through a selective dual-step process and contains proteins involved in plant defence.

PubMed

Scarafoni, Alessio; Ronchi, Alessandro; Prinsi, Bhakti; Espen, Luca; Assante, Gemma; Venturini, Giovanni; Duranti, Marcello

2013-03-01

The general knowledge of defence activity during the first steps of seed germination is still largely incomplete. The present study focused on the proteins released in the exudates of germinating white lupin seeds. During the first 24 h, a release of proteins was observed. Initially (i.e. during the first 12 h), the proteins found in exudates reflected the composition of the seed, indicating a passive extrusion of pre-formed proteins. Subsequently, when the rate of protein release was at its highest, the composition of the released proteome changed drastically. This transition occurred in a short time, indicating that more selective and regulated events, such as secretory processes, took place soon after the onset of germination. The present study considered: (a) the characterization of the proteome accumulated in the germinating medium collected after the appearance of the post-extrusion events; (b) the biosynthetic origin and the modalities that are the basis of protein release outside the seeds; and (c) an assessment of antifungal activity of these exudates. The most represented protein in the exudate was chitinase, which was synthesized de novo. The other proteins are involved in the cellular mechanisms responding to stress events, including biotic ones. This exudate was effectively able to inhibit fungal growth. The results of the present study indicate that seed exudation is a dual-step process that leads to the secretion of selected proteins and thus is not a result of passive leakage. The released proteome is involved in protecting the spermosphere environment and thus may act as first defence against pathogens. © 2013 The Authors Journal compilation © 2013 FEBS.

Comparison of dual and single exposure techniques in dual-energy chest radiography.

PubMed

Ho, J T; Kruger, R A; Sorenson, J A

1989-01-01

Conventional chest radiography is the most effective tool for lung cancer detection and diagnosis; nevertheless, a high percentage of lung cancer tumors are missed because of the overlap of lung nodule image contrast with bone image contrast in a chest radiograph. Two different energy subtraction strategies, dual exposure and single exposure techniques, were studied for decomposing a radiograph into bone-free and soft tissue-free images to address this problem. For comparing the efficiency of these two techniques in lung nodule detection, the performances of the techniques were evaluated on the basis of residual tissue contrast, energy separation, and signal-to-noise ratio. The evaluation was based on both computer simulation and experimental verification. The dual exposure technique was found to be better than the single exposure technique because of its higher signal-to-noise ratio and greater residual tissue contrast. However, x-ray tube loading and patient motion are problems.

[The mechanism of phenoptosis: I. Age-dependent decrease of the overall rate of protein synthesis is caused by the programmed attenuation of bio-energetics].

PubMed

Trubitsyn, A G

2009-01-01

The age-dependent degradation of all vital processes of an organism can be result of influences of destructive factors (the stochastic mechanism of aging), or effect of realizations of the genetic program (phenoptosis). The stochastic free-radical theory of aging dominating now contradicts the set of empirical data, and the semicentenial attempts to create the means to slow down aging did not give any practical results. It makes obvious that the stochastic mechanism of aging is incorrect. At the same time, the alternative mechanism of the programmed aging is not developed yet but preconditions for it development have already been created. It is shown that the genes controlling process of aging exist (contrary to the customary opinion) and the increase in the level of damaged macromolecules (basic postulate of the free-radical theory) can be explained by programmed attenuation of bio-energetics. As the bio-energetics is a driving force of all vital processes, decrease of its level is capable to cause degradation of all functions of an organism. However to transform this postulate into a basis of the theory of phenoptosis it is necessary to show, that attenuation of bio-energetics predetermines such fundamental processes accompanying aging as decrease of the overall rate of protein biosynthesis, restriction of cellular proliferations (Hayflick limit), loss of telomeres etc. This article is the first step in this direction: the natural mechanism of interaction of overall rate of protein synthesis with a level of cellular bio-energetics is shown. This is built-in into the translation machine and based on dependence of recirculation rate of eukaryotic initiation factor 2 (elF2) from ATP/ADP value that is created by mitochondrial bio-energetic machine.

Pattern similarity study of functional sites in protein sequences: lysozymes and cystatins

PubMed Central

Nakai, Shuryo; Li-Chan, Eunice CY; Dou, Jinglie

2005-01-01

Background Although it is generally agreed that topography is more conserved than sequences, proteins sharing the same fold can have different functions, while there are protein families with low sequence similarity. An alternative method for profile analysis of characteristic conserved positions of the motifs within the 3D structures may be needed for functional annotation of protein sequences. Using the approach of quantitative structure-activity relationships (QSAR), we have proposed a new algorithm for postulating functional mechanisms on the basis of pattern similarity and average of property values of side-chains in segments within sequences. This approach was used to search for functional sites of proteins belonging to the lysozyme and cystatin families. Results Hydrophobicity and β-turn propensity of reference segments with 3–7 residues were used for the homology similarity search (HSS) for active sites. Hydrogen bonding was used as the side-chain property for searching the binding sites of lysozymes. The profiles of similarity constants and average values of these parameters as functions of their positions in the sequences could identify both active and substrate binding sites of the lysozyme of Streptomyces coelicolor, which has been reported as a new fold enzyme (Cellosyl). The same approach was successfully applied to cystatins, especially for postulating the mechanisms of amyloidosis of human cystatin C as well as human lysozyme. Conclusion Pattern similarity and average index values of structure-related properties of side chains in short segments of three residues or longer were, for the first time, successfully applied for predicting functional sites in sequences. This new approach may be applicable to studying functional sites in un-annotated proteins, for which complete 3D structures are not yet available. PMID:15904486

Application of the dual-kinetic-balance sets in the relativistic many-body problem of atomic structure

NASA Astrophysics Data System (ADS)

Beloy, Kyle; Derevianko, Andrei

2008-05-01

The dual-kinetic-balance (DKB) finite basis set method for solving the Dirac equation for hydrogen-like ions [V. M. Shabaev et al., Phys. Rev. Lett. 93, 130405 (2004)] is extended to problems with a non-local spherically-symmetric Dirac-Hartree-Fock potential. We implement the DKB method using B-spline basis sets and compare its performance with the widely- employed approach of Notre Dame (ND) group [W.R. Johnson, S.A. Blundell, J. Sapirstein, Phys. Rev. A 37, 307-15 (1988)]. We compare the performance of the ND and DKB methods by computing various properties of Cs atom: energies, hyperfine integrals, the parity-non-conserving amplitude of the 6s1/2-7s1/2 transition, and the second-order many-body correction to the removal energy of the valence electrons. We find that for a comparable size of the basis set the accuracy of both methods is similar for matrix elements accumulated far from the nuclear region. However, for atomic properties determined by small distances, the DKB method outperforms the ND approach.

Adult Hippocampal Neurogenesis in the Pathogenesis of Addiction and Dual Diagnosis Disorders

PubMed Central

Chambers, R. Andrew

2013-01-01

Background As knowledge deepens about how new neurons are born, differentiate, and wire into the adult mammalian brain, growing evidence depicts hippocampal neurogenesis as a special form of neuroplasticity that may be impaired across psychiatric disorders. This review provides an integrated-evidence based framework describing a neurogenic basis for addictions and addiction vulnerability in mental illness. Methods Basic studies conducted over the last decade examining the effects of addictive drugs on adult neurogenesis and the impact of neurogenic activity on addictive behavior were compiled and integrated with relevant neurocomputational and human studies. Results While suppression of hippocampal neurogenic proliferation appears to be a universal property of addictive drugs, the pathophysiology of addictions involves neuroadaptative processes within frontal-cortical-striatal motivation circuits that the neurogenic hippocampus regulates via direct projections. States of suppressed neurogenic activity may simultaneously underlie psychiatric and cognitive symptoms, but also confer or signify hippocampal dysfunction that heightens addiction vulnerability in mental illness as a basis for dual diagnosis disorders. Conclusions Research on pharmacological, behavioral and experiential strategies that enhance adaptive regulation of hippocampal neurogenesis holds potential in advancing preventative and integrative treatment strategies for addictions and dual diagnosis disorders. PMID:23279925

Adult hippocampal neurogenesis in the pathogenesis of addiction and dual diagnosis disorders.

PubMed

Chambers, R Andrew

2013-06-01

As knowledge deepens about how new neurons are born, differentiate, and wire into the adult mammalian brain, growing evidence depicts hippocampal neurogenesis as a special form of neuroplasticity that may be impaired across psychiatric disorders. This review provides an integrated-evidence based framework describing a neurogenic basis for addictions and addiction vulnerability in mental illness. Basic studies conducted over the last decade examining the effects of addictive drugs on adult neurogenesis and the impact of neurogenic activity on addictive behavior were compiled and integrated with relevant neurocomputational and human studies. While suppression of hippocampal neurogenic proliferation appears to be a universal property of addictive drugs, the pathophysiology of addictions involves neuroadaptative processes within frontal-cortical-striatal motivation circuits that the neurogenic hippocampus regulates via direct projections. States of suppressed neurogenic activity may simultaneously underlie psychiatric and cognitive symptoms, but also confer or signify hippocampal dysfunction that heightens addiction vulnerability in mental illness as a basis for dual diagnosis disorders. Research on pharmacological, behavioral and experiential strategies that enhance adaptive regulation of hippocampal neurogenesis holds potential in advancing preventative and integrative treatment strategies for addictions and dual diagnosis disorders. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The Impact of Coping Flexibility on the Risk of Depressive Symptoms

PubMed Central

Kato, Tsukasa

2015-01-01

Objective According to the dual-process theory, coping flexibility is defined as the ability to produce and implement a new coping strategy in place of an ineffective coping strategy. Specifically, coping flexibility includes two processes: evaluation coping and adaptive coping. Evaluation coping refers to sensitivity to feedback about the efficacy of a coping strategy, and adaptive coping involves the willingness to implement alternative coping strategies. The coping flexibility hypothesis (CFH) postulates that more flexible coping will be associated with more adaptive outcomes; importantly, there are numerous theories and studies that support the CFH. The main purpose of this study was to test the CFH based on dual-process theory. Methods A total of 1,770 Japanese college students participated and, completed a set of questionnaires that measured coping flexibility (evaluation coping and adaptive coping) and depressive symptoms. Depressive symptoms were measured via the Center for Epidemiologic Studies Depression Scale. Results The proportions of women and men who reported depressive symptoms were 58.69% (95% CIs [55.74, 61.66]) and 54.17% (95% CIs [50.37, 57.95]), respectively when a cut-off score of 16 on the CES-D was used. A multivariable logistic regression analysis revealed that evaluation coping (OR = 0.86, 95% CIs [0.83, 0.0.89]) and adaptive coping (OR = 0.91, 95% CIs [0.88, 0.93]) were significantly associated with lower levels of depressive symptoms. Conclusion The results of the present study indicated that the CFH based on dual-process theory was supported in a Japanese sample. PMID:26011626

Fringe formation in dual-hologram interferometry

NASA Technical Reports Server (NTRS)

Burner, A. W.

1990-01-01

Reference-fringe formation in nondiffuse dual-hologram interferometry is described by combining a first-order geometrical hologram treatment with interference fringes generated by two point sources. The first-order imaging relationships can be used to describe reference-fringe patterns for the geometry of the dual-hologram interferometry. The process can be completed without adjusting the two holograms when the reconstructing wavelength is less than the exposing wavelength, and the process is found to facilitate basic intereferometer adjustments.

Use of an auxiliary basis set to describe the polarization in the fragment molecular orbital method

NASA Astrophysics Data System (ADS)

Fedorov, Dmitri G.; Kitaura, Kazuo

2014-03-01

We developed a dual basis approach within the fragment molecular orbital formalism enabling efficient and accurate use of large basis sets. The method was tested on water clusters and polypeptides and applied to perform geometry optimization of chignolin (PDB: 1UAO) in solution at the level of DFT/6-31++G∗∗, obtaining a structure in agreement with experiment (RMSD of 0.4526 Å). The polarization in polypeptides is discussed with a comparison of the α-helix and β-strand.

Comparison study of image quality and effective dose in dual energy chest digital tomosynthesis

NASA Astrophysics Data System (ADS)

Lee, Donghoon; Choi, Sunghoon; Lee, Haenghwa; Kim, Dohyeon; Choi, Seungyeon; Kim, Hee-Joung

2018-07-01

The present study aimed to introduce a recently developed digital tomosynthesis system for the chest and describe the procedure for acquiring dual energy bone decomposed tomosynthesis images. Various beam quality and reconstruction algorithms were evaluated for acquiring dual energy chest digital tomosynthesis (CDT) images and the effective dose was calculated with ion chamber and Monte Carlo simulations. The results demonstrated that dual energy CDT improved visualization of the lung field by eliminating the bony structures. In addition, qualitative and quantitative image quality of dual energy CDT using iterative reconstruction was better than that with filtered backprojection (FBP) algorithm. The contrast-to-noise ratio and figure of merit values of dual energy CDT acquired with iterative reconstruction were three times better than those acquired with FBP reconstruction. The difference in the image quality according to the acquisition conditions was not noticeable, but the effective dose was significantly affected by the acquisition condition. The high energy acquisition condition using 130 kVp recorded a relatively high effective dose. We conclude that dual energy CDT has the potential to compensate for major problems in CDT due to decomposed bony structures, which induce significant artifacts. Although there are many variables in the clinical practice, our results regarding reconstruction algorithms and acquisition conditions may be used as the basis for clinical use of dual energy CDT imaging.

Synovial fluid hyaluronan mediates MSC attachment to cartilage, a potential novel mechanism contributing to cartilage repair in osteoarthritis using knee joint distraction.

PubMed

Baboolal, Thomas G; Mastbergen, Simon C; Jones, Elena; Calder, Stuart J; Lafeber, Floris P J G; McGonagle, Dennis

2016-05-01

Knee joint distraction (KJD) is a novel, but poorly understood, treatment for osteoarthritis (OA) associated with remarkable 'spontaneous' cartilage repair in which resident synovial fluid (SF) multipotential mesenchymal stromal cells (MSCs) may play a role. We hypothesised that SF hyaluronic acid (HA) inhibited the initial interaction between MSCs and cartilage, a key first step to integration, and postulate that KJD environment favoured MSC/cartilage interactions. Attachment of dual-labelled SF-MSCs were assessed in a novel in vitro human cartilage model using OA and rheumatoid arthritic (RA) SF. SF was digested with hyaluronidase (hyase) and its effect on adhesion was observed using confocal microscopy. MRI and microscopy were used to image autologous dual-labelled MSCs in an in vivo canine model of KJD. SF-HA was investigated using gel electrophoresis and densitometry. Osteoarthritic-synovial fluid (OA-SF) and purified high molecular weight (MW) HA inhibited SF-MSC adhesion to plastic, while hyase treatment of OA-SF but not RA-SF significantly increased MSC adhesion to cartilage (3.7-fold, p<0.05) These differences were linked to the SF mediated HA-coat which was larger in OA-SF than in RA-SF. OA-SF contained >9 MDa HA and this correlated with increases in adhesion (r=0.880). In the canine KJD model, MSC adhesion to cartilage was evident and also dependent on HA MW. These findings highlight an unappreciated role of SF-HA on MSC interactions and provide proof of concept that endogenous SF-MSCs are capable of adhering to cartilage in a favourable biochemical and biomechanical environment in OA distracted joints, offering novel one-stage strategies towards joint repair. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Structural models of the MscL gating mechanism

NASA Technical Reports Server (NTRS)

Sukharev, S.; Durell, S. R.; Guy, H. R.

2001-01-01

Three-dimensional structural models of the mechanosensitive channel of large conductance, MscL, from the bacteria Mycobacterium tuberculosis and Escherichia coli were developed for closed, intermediate, and open conformations. The modeling began with the crystal structure of M. tuberculosis MscL, a homopentamer with two transmembrane alpha-helices, M1 and M2, per subunit. The first 12 N-terminal residues, not resolved in the crystal structure, were modeled as an amphipathic alpha-helix, called S1. A bundle of five parallel S1 helices are postulated to form a cytoplasmic gate. As membrane tension induces expansion, the tilts of M1 and M2 are postulated to increase as they move away from the axis of the pore. Substantial expansion is postulated to occur before the increased stress in the S1 to M1 linkers pulls the S1 bundle apart. During the opening transition, the S1 helices and C-terminus amphipathic alpha-helices, S3, are postulated to dock parallel to the membrane surface on the perimeter of the complex. The proposed gating mechanism reveals critical spatial relationships between the expandable transmembrane barrel formed by M1 and M2, the gate formed by S1 helices, and "strings" that link S1s to M1s. These models are consistent with numerous experimental results and modeling criteria.

Prefrontal oxygenation and the acoustic startle eyeblink response during exercise: A test of the dual-mode model.

PubMed

Tempest, Gavin D; Parfitt, Gaynor

2017-07-01

The interplay between the prefrontal cortex and amygdala is proposed to explain the regulation of affective responses (pleasure/displeasure) during exercise as outlined in the dual-mode model. However, due to methodological limitations the dual-mode model has not been fully tested. In this study, prefrontal oxygenation (using near-infrared spectroscopy) and amygdala activity (reflected by eyeblink amplitude using acoustic startle methodology) were recorded during exercise standardized to metabolic processes: 80% of ventilatory threshold (below VT), at the VT, and at the respiratory compensation point (RCP). Self-reported tolerance of the intensity of exercise was assessed prior to, and affective responses recorded during exercise. The results revealed that, as the intensity of exercise became more challenging (from below VT to RCP), prefrontal oxygenation was larger and eyeblink amplitude and affective responses were reduced. Below VT and at VT, larger prefrontal oxygenation was associated with larger eyeblink amplitude. At the RCP, prefrontal oxygenation was greater in the left than right hemisphere, and eyeblink amplitude explained significant variance in affective responses (with prefrontal oxygenation) and self-reported tolerance. These findings highlight the role of the prefrontal cortex and potentially the amygdala in the regulation of affective (particularly negative) responses during exercise at physiologically challenging intensities (above VT). In addition, a psychophysiological basis of self-reported tolerance is indicated. This study provides some support of the dual-mode model and insight into the neural basis of affective responses during exercise. © 2017 Society for Psychophysiological Research.

Excitation of Higher Order Modes of Cylindrical Dielectric Resonator Antenna using Dual-slot feed

NASA Astrophysics Data System (ADS)

Ojha, A. K.; Praveen Kumar, A. V.

2018-03-01

Excitation of the higher order modes (HOM) of a cylindrical dielectric resonator antenna(DRA) of high relative permittivity, using dual feed scheme is investigated. The feed scheme uses a pair of narrow slots and is chosen on the basis of the field distribution of the desired DRA modes. Numerical studies using ANSYS HFSS show that the dual-feed excited a combination of two HOMs, which are identified as HEM21δ and TM01δ. The mixed-up nature is further verified through studying the radiation pattern of the DRA which shows azimuthal asymmetry and low gain. It is suggested that if one of the HOM is suppressed, better antenna performance can be achieved.

Design, synthesis and structure-activity relationships of dual inhibitors of acetylcholinesterase and serotonin transporter as potential agents for Alzheimer's disease.

PubMed

Toda, Narihiro; Tago, Keiko; Marumoto, Shinji; Takami, Kazuko; Ori, Mayuko; Yamada, Naho; Koyama, Kazuo; Naruto, Shunji; Abe, Kazumi; Yamazaki, Reina; Hara, Takao; Aoyagi, Atsushi; Abe, Yasuyuki; Kaneko, Tsugio; Kogen, Hiroshi

2003-05-01

We have designed and synthesized a dual inhibitor of acetylcholinesterase (AChE) and serotonin transporter (SERT) as a novel class of treatment drugs for Alzheimer's disease on the basis of a hypothetical model of the AChE active site. Dual inhibitions of AChE and SERT would bring about greater therapeutic effects than AChE inhibition alone and avoid adverse peripheral effects caused by excessive AChE inhibition. Compound (S)-6j exhibited potent inhibitory activities against AChE (IC(50)=101 nM) and SERT (IC(50)=42 nM). Furthermore, (S)-6j showed inhibitory activities of both AChE and SERT in mice brain following oral administration.

Bimodal wireless sensing with dual-channel wide bandgap heterostructure varactors

NASA Astrophysics Data System (ADS)

Deen, David A.; Osinsky, Andrei; Miller, Ross

2014-03-01

A capacitive wireless sensing scheme is developed that utilizes an AlN/GaN-based dual-channel varactor. The dual-channel heterostructure affords two capacitance plateaus within the capacitance-voltage (CV) characteristic, owing to the two parallel two-dimensional electron gases (2DEGs) located at respective AlN/GaN interfaces. The capacitance plateaus are leveraged for the definition of two resonant states of the sensor when implemented in an inductively-coupled resonant LRC network for wireless readout. The physics-based CV model is compared with published experimental results, which serve as a basis for the sensor embodiment. The bimodal resonant sensor is befitting for a broad application space ranging from gas, electrostatic, and piezoelectric sensors to biological and chemical detection.

First observations of SPEAR-induced topside and bottomside sporadic E layer heating observed using the EISCAT Svalbard and SuperDARN radars

NASA Astrophysics Data System (ADS)

Baddeley, L. J.; Haggstrøm, I.; Yeoman, T. K.; Rietveld, M.

2012-01-01

We present the first observations of heater-induced simultaneous topside and bottomside sporadic E layer enhancements at very high latitudes (78.15°N) using the Space Plasma Exploration by Active Radar (SPEAR) heating facility and the European Incoherent Scatter (EISCAT) Svalbard Radar. During the experiment the SPEAR heating facility was transmitting with O-mode polarization in a field-aligned direction with a constant effective radiated power of ˜16 MW. Results show distinct heater-induced enhancements in both the ion and plasma line spectra. The plasma line enhancements are observed at the SPEAR heater frequency of 4.45 MHz. The plasma line observations represent the highest spatial resolution data (100 m) obtained of such heater-induced enhancements and indicate simultaneous enhancements at both the topside and bottomside of the layer, respectively (located at ˜107.5 and 109 km altitude, respectively). It is postulated that the results represent evidence of O- to Z-mode conversion of the heater wave occurring at the bottom of the E layer, allowing propagation through the layer resulting in simultaneous topside enhancements. The Z-mode enhancements are observed outside the Spitze angle, which is thought to be a result of field-aligned irregularities causing an increase in angular extent of the observations. Additional data from the Super Dual Auroral Radar Network (SuperDARN) HF Finland radar are also shown, which indicate that upon a thinning of the sporadic E layer, the heater beam propagated into the F region, where it induced artificial field-aligned irregularities.

Evolutionary and preservational constraints on origins of biologic groups: divergence times of eutherian mammals

NASA Technical Reports Server (NTRS)

Foote, M.; Hunter, J. P.; Janis, C. M.; Sepkoski, J. J. Jr

1999-01-01

Some molecular clock estimates of divergence times of taxonomic groups undergoing evolutionary radiation are much older than the groups' first observed fossil record. Mathematical models of branching evolution are used to estimate the maximal rate of fossil preservation consistent with a postulated missing history, given the sum of species durations implied by early origins under a range of species origination and extinction rates. The plausibility of postulated divergence times depends on origination, extinction, and preservation rates estimated from the fossil record. For eutherian mammals, this approach suggests that it is unlikely that many modern orders arose much earlier than their oldest fossil records.

Dual-Hit Hypothesis Explains Pulmonary Hypoplasia in the Nitrofen Model of Congenital Diaphragmatic Hernia

PubMed Central

Keijzer, Richard; Liu, Jason; Deimling, Julie; Tibboel, Dick; Post, Martin

2000-01-01

Pulmonary hypoplasia associated with congenital diaphragmatic hernia (CDH) remains a major therapeutic problem. Moreover, the pathogenesis of pulmonary hypoplasia in case of CDH is controversial. In particular, little is known about early lung development in this anomaly. To investigate lung development separate from diaphragm development we used an in vitro modification of the 2,4-dichlorophenyl-p-nitrophenylether (Nitrofen) animal model for CDH. This enabled us to investigate the direct effects of Nitrofen on early lung development and branching morphogenesis in an organotypic explant system without the influence of impaired diaphragm development. Epithelial cell differentiation of the lung explants was assessed using surfactant protein-C and Clara cell secretory protein-10 mRNA expression as markers. Furthermore, cell proliferation and apoptosis were investigated. Our results indicate that Nitrofen negatively influences branching morphogenesis of the lung. Initial lung anlage formation is not affected. In addition, epithelial cell differentiation and cell proliferation are attenuated in lungs exposed to Nitrofen. These data indicate that Nitrofen interferes with early lung development before and separate from (aberrant) diaphragm development. Therefore, we postulate the dual-hit hypothesis, which explains pulmonary hypoplasia in CDH by two insults, one affecting both lungs before diaphragm development and one affecting the ipsilateral lung after defective diaphragm development. PMID:10751355

Electrochemical aptasensor based on the dual-amplification of G-quadruplex horseradish peroxidase-mimicking DNAzyme and blocking reagent-horseradish peroxidase.

PubMed

Yuan, Yali; Gou, Xuxu; Yuan, Ruo; Chai, Yaqin; Zhuo, Ying; Mao, Li; Gan, Xianxue

2011-06-15

A simple electrochemical aptasensor for sensitive detection of thrombin was fabricated with G-quadruplex horseradish peroxidase-mimicking DNAzyme (hemin/G-quadruplex system) and blocking reagent-horseradish peroxidase as dual signal-amplification scheme. Gold nanoparticles (nano-Au) were firstly electrodeposited onto single wall nanotube (SWNT)-graphene modified electrode surface for the immobilization of electrochemical probe of nickel hexacyanoferrates nanoparticles (NiHCFNPs). Subsequently, another nano-Au layer was electrodeposited for further immobilization of thrombin aptamer (TBA), which later formed hemin/G-quadruplex system with hemin. Horseradish peroxidases (HRP) then served as blocking reagent to block possible remaining active sites and avoided the non-specific adsorption. In the presence of thrombin, the TBA binded to thrombin and the hemin released from the hemin/G-quadruplex electrocatalytic structure, increasing steric hindrance of the aptasensor and decomposing hemin/G-quadruplex electrocatalytic structure, which finally decreased the electrocatalytic efficiency of aptasensor toward H(2)O(2) in the presence of NiHCFNPs with a decreased electrochemical signal. On the basis of the synergistic amplifying action, a detection limit as low as 2 pM for thrombin was obtained. Copyright © 2011 Elsevier B.V. All rights reserved.

Neural basis of nonanalytical reasoning expertise during clinical evaluation.

PubMed

Durning, Steven J; Costanzo, Michelle E; Artino, Anthony R; Graner, John; van der Vleuten, Cees; Beckman, Thomas J; Wittich, Christopher M; Roy, Michael J; Holmboe, Eric S; Schuwirth, Lambert

2015-03-01

Understanding clinical reasoning is essential for patient care and medical education. Dual-processing theory suggests that nonanalytic reasoning is an essential aspect of expertise; however, assessing nonanalytic reasoning is challenging because it is believed to occur on the subconscious level. This assumption makes concurrent verbal protocols less reliable assessment tools. Functional magnetic resonance imaging was used to explore the neural basis of nonanalytic reasoning in internal medicine interns (novices) and board-certified staff internists (experts) while completing United States Medical Licensing Examination and American Board of Internal Medicine multiple-choice questions. The results demonstrated that novices and experts share a common neural network in addition to nonoverlapping neural resources. However, experts manifested greater neural processing efficiency in regions such as the prefrontal cortex during nonanalytical reasoning. These findings reveal a multinetwork system that supports the dual-process mode of expert clinical reasoning during medical evaluation.

Being qua becoming: Aristotle's "Metaphysics", quantum physics, and Process Philosophy

NASA Astrophysics Data System (ADS)

Johnson, David Kelley

In Aristotle's First Philosophy, science and philosophy were partners, but with the rise of empiricism, went their separate ways. Metaphysics combined the rational and irrational (i.e. final cause/unmoved mover) elements of existence to equate being with substance, postulating prime matter as pure potential that was actuated by form to create everything. Modern science reveres pure reason and postulates its theory of being by a rigorous scientific methodology. The Standard Model defines matter as energy formed into fundamental particles via forces contained in fields. Science has proved Aristotle's universe wrong in many ways, but as physics delves deeper into the quantum world, empiricism is reaching its limits concerning fundamental questions of existence. To achieve its avowed mission of explaining existence completely, physics must reunite with philosophy in a metascience modeled on the First Philosophy of Aristotle. One theory of being that integrates quantum physics and metaphysics is Process Philosophy.

First Amendment Speech and Press Theory: Preferred Position Postulate Reexamined.

ERIC Educational Resources Information Center

Stonecipher, Harry W.

If the United States Supreme Court is to exercise its historic role as guardian of the fundamental freedoms flowing from the speech and press clauses of the first amendment, it is imperative that those basic freedoms be placed in a preferred position. The preferred position doctrine provides adequate safeguards for both speech and press guarantees…

Immigrants and Suffrage: Adding to the Discourse by Integrating State versus National Citizenship, Dual Domestic Residency, and Dual Citizenship

ERIC Educational Resources Information Center

Garcia, John A.

2012-01-01

This article builds upon the literature on immigrants and the vote by focusing on three legal and democratic principles: state versus national citizenship, dual domestic residency, and globalization/dual citizenship. It first delineates the discretion and powers that states can utilize to establish suffrage rights. The article next develops…

Wormhole and entanglement (non-)detection in the ER=EPR correspondence

DOE PAGES

Bao, Ning; Pollack, Jason; Remmen, Grant N.

2015-11-19

The recently proposed ER=EPR correspondence postulates the existence of wormholes (Einstein-Rosen bridges) between entangled states (such as EPR pairs). Entanglement is famously known to be unobservable in quantum mechanics, in that there exists no observable (or, equivalently, projector) that can accurately pick out whether a generic state is entangled. Many features of the geometry of spacetime, however, are observables, so one might worry that the presence or absence of a wormhole could identify an entangled state in ER=EPR, violating quantum mechanics, specifically, the property of state-independence of observables. In this note, we establish that this cannot occur: there is nomore » measurement in general relativity that unambiguously detects the presence of a generic wormhole geometry. Furthermore, this statement is the ER=EPR dual of the undetectability of entanglement.« less

Attention, motivation, and reading coherence failure: a neuropsychological perspective.

PubMed

Wasserman, Theodore

2012-01-01

Reading coherence, defined as the ability to create appropriate, meaningful connections between the elements within a specific text itself and between elements within a text and the reader's prior knowledge, is one of the key processes involved in reading comprehension. This article describes reading coherence within the context of a neuropsychological model combining recent research in motivation, attention, and working memory. Specifically, a unique neuropsychologically identifiable form of reading coherence failure arising from the attentional and motivational deficiencies, based in altered frontoventral striatal reward circuits associated with noradrenaline (NA) circuitry, consistent with the delay-aversion model (dual-pathway model) of Sonuga-Barke ( 2003 ) is postulated. This article provides a model for this subset of reading disorders of which etiology is based on the executive support processes for reading and not in the mechanics of actual reading such as decoding and phonetics.

Approaching the theoretical limit in periodic local MP2 calculations with atomic-orbital basis sets: the case of LiH.

PubMed

Usvyat, Denis; Civalleri, Bartolomeo; Maschio, Lorenzo; Dovesi, Roberto; Pisani, Cesare; Schütz, Martin

2011-06-07

The atomic orbital basis set limit is approached in periodic correlated calculations for solid LiH. The valence correlation energy is evaluated at the level of the local periodic second order Møller-Plesset perturbation theory (MP2), using basis sets of progressively increasing size, and also employing "bond"-centered basis functions in addition to the standard atom-centered ones. Extended basis sets, which contain linear dependencies, are processed only at the MP2 stage via a dual basis set scheme. The local approximation (domain) error has been consistently eliminated by expanding the orbital excitation domains. As a final result, it is demonstrated that the complete basis set limit can be reached for both HF and local MP2 periodic calculations, and a general scheme is outlined for the definition of high-quality atomic-orbital basis sets for solids. © 2011 American Institute of Physics

Gas Flows in Dual Active Galactic Nuclei

NASA Astrophysics Data System (ADS)

Mueller Sanchez, Francisco; Comerford, Julia M.; Davies, Richard; Treister, Ezequiel; Privon, George C.; Nevin, Becky

2018-06-01

Dual Active Galactic Nuclei (AGN) are the Rosetta stone to understand the role of galaxy mergers in triggering nuclear activity and regulating black hole (BH) and galaxy growth. But very little is known about the physical processes required to effectively trigger AGN activity and regulate the growth of the two BHs. The work I will present here characterizes for the first time the properties of the stars, gas (molecular, ionized, and highly-ionized) and dust in all the confirmed dual AGN at z < 0.05, using Keck/OSIRIS, VLT/SINFONI, SOFIA/FORCAST, and HST data. I will focus on the interplay between the several complex processes observed in dual AGN, using as an example the prototypical merger system NGC 6240: vigorous star formation, two AGNs, outflowing winds of ionized gas, rippling dust and gas lanes, and tidal tails. In this galaxy, we observe for the first time a dual outflow of different species of gas: an AGN-driven outflow of highly-ionized gas to the northeast and a starburst-driven outflow of ionized hydrogen to the northwest. This shows that stellar feedback and supermassive black hole feedback can work in tandem to regulate the stellar growth of a galaxy after a merger event. These results open a new door to studies of dual AGN and AGN pairs in general, and enable dual AGN to be used, for the first time, for studies of galaxy evolution.

Development of dual field magnetic flux leakage (MFL) inspection technology to detect mechanical damage.

DOT National Transportation Integrated Search

2013-03-01

This report details the development and testing of a dual magnetization in-line inspection (ILI) : tool for detecting mechanical damage in operating pipelines, including the first field trials of a : fully operational dual-field magnetic flux leakage...

On the Scaling Law for Broadband Shock Noise Intensity in Supersonic Jets

NASA Technical Reports Server (NTRS)

Kanudula, Max

2009-01-01

A theoretical model for the scaling of broadband shock noise intensity in supersonic jets was formulated on the basis of linear shock-shear wave interaction. An hypothesis has been postulated that the peak angle of incidence (closer to the critical angle) for the shear wave primarily governs the generation of sound in the interaction process rather than the noise generation contribution from off-peak incident angles. The proposed theory satisfactorily explains the well-known scaling law for the broadband shock -associated noise in supersonic jets.

C/sub 60/La: a deflated soccer ball

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

Cox, D.M.; Trevor, D.J.; Reichmann, K.C.

1986-04-30

A recent paper reported very exciting results; the production and detection of C/sub n/La complexes, n = 44, 46, 48,...76, with n = 60 the dominant species. For the dominant C/sub n/La species, C/sub 60/La, the metal atom was postulated, on the basis of the experimental photoionization mass spectroscopy data, to be strongly bound within a spheroidal carbon shell possessing unusually high stability. In this paper we present further experimental evidence which when added to the information presented by HOZLCKTS and Kroto et al. (KHOCS) seriously challenges this enticing conclusion.

Investigation of naphthofuran moiety as potential dual inhibitor against BACE-1 and GSK-3β: molecular dynamics simulations, binding energy, and network analysis to identify first-in-class dual inhibitors against Alzheimer's disease.

PubMed

Kumar, Akhil; Srivastava, Gaurava; Srivastava, Swati; Verma, Seema; Negi, Arvind S; Sharma, Ashok

2017-08-01

BACE-1 and GSK-3β are potential therapeutic drug targets for Alzheimer's disease. Recently, both the targets received attention for designing dual inhibitors for Alzheimer's disease. Until now, only two-scaffold triazinone and curcumin have been reported as BACE-1 and GSK-3β dual inhibitors. Docking, molecular dynamics, clustering, binding energy, and network analysis of triazinone derivatives with BACE-1 and GSK-3β was performed to get molecular insight into the first reported dual inhibitor. Further, we designed and evaluated a naphthofuran series for its ability to inhibit BACE-1 and GSK-3β with the computational approaches. Docking study of naphthofuran series showed a good binding affinity towards both the targets. Molecular dynamics, binding energy, and network analysis were performed to compare their binding with the targets and amino acids responsible for binding. Naphthofuran series derivatives showed good interaction within the active site residues of both of the targets. Hydrogen bond occupancy and binding energy suggested strong binding with the targets. Dual-inhibitor binding was mostly governed by the hydrophobic interactions for both of the targets. Per residue energy decomposition and network analysis identified the key residues involved in the binding and inhibiting BACE-1 and GSK-3β. The results indicated that naphthofuran series derivative 11 may be a promising first-in-class dual inhibitor against BACE-1 and GSK-3β. This naphthofuran series may be further explored to design better dual inhibitors. Graphical abstract Naphthofuran derivative as a dual inhibitor for BACE-1 and GSK-3β.

Unravelling the distinct strains of Tharu ancestry

PubMed Central

Chaubey, Gyaneshwer; Singh, Manvendra; Crivellaro, Federica; Tamang, Rakesh; Nandan, Amrita; Singh, Kamayani; Sharma, Varun Kumar; Pathak, Ajai Kumar; Shah, Anish M; Sharma, Vishwas; Singh, Vipin Kumar; Selvi Rani, Deepa; Rai, Niraj; Kushniarevich, Alena; Ilumäe, Anne-Mai; Karmin, Monika; Phillip, Anand; Verma, Abhilasha; Prank, Erik; Singh, Vijay Kumar; Li, Blaise; Govindaraj, Periyasamy; Chaubey, Akhilesh Kumar; Dubey, Pavan Kumar; Reddy, Alla G; Premkumar, Kumpati; Vishnupriya, Satti; Pande, Veena; Parik, Jüri; Rootsi, Siiri; Endicott, Phillip; Metspalu, Mait; Lahr, Marta Mirazon; van Driem, George; Villems, Richard; Kivisild, Toomas; Singh, Lalji; Thangaraj, Kumarasamy

2014-01-01

The northern region of the Indian subcontinent is a vast landscape interlaced by diverse ecologies, for example, the Gangetic Plain and the Himalayas. A great number of ethnic groups are found there, displaying a multitude of languages and cultures. The Tharu is one of the largest and most linguistically diverse of such groups, scattered across the Tarai region of Nepal and bordering Indian states. Their origins are uncertain. Hypotheses have been advanced postulating shared ancestry with Austroasiatic, or Tibeto-Burman-speaking populations as well as aboriginal roots in the Tarai. Several Tharu groups speak a variety of Indo-Aryan languages, but have traditionally been described by ethnographers as representing East Asian phenotype. Their ancestry and intra-population diversity has previously been tested only for haploid (mitochondrial DNA and Y-chromosome) markers in a small portion of the population. This study presents the first systematic genetic survey of the Tharu from both Nepal and two Indian states of Uttarakhand and Uttar Pradesh, using genome-wide SNPs and haploid markers. We show that the Tharu have dual genetic ancestry as up to one-half of their gene pool is of East Asian origin. Within the South Asian proportion of the Tharu genetic ancestry, we see vestiges of their common origin in the north of the South Asian Subcontinent manifested by mitochondrial DNA haplogroup M43. PMID:24667789

Dual-filter estimation for rotating-panel sample designs

Treesearch

Francis Roesch

2017-01-01

Dual-filter estimators are described and tested for use in the annual estimation for national forest inventories. The dual-filter approach involves the use of a moving widow estimator in the first pass, which is used as input to Theil’s mixed estimator in the second pass. The moving window and dual-filter estimators are tested along with two other estimators in a...

Genetics and pathological mechanisms of Usher syndrome.

PubMed

Yan, Denise; Liu, Xue Z

2010-06-01

Usher syndrome (USH) comprises a group of autosomal recessively inherited disorders characterized by a dual sensory impairment of the audiovestibular and visual systems. Three major clinical subtypes (USH type I, USH type II and USH type III) are distinguished on the basis of the severity of the hearing loss, the presence or absence of vestibular dysfunction and the age of onset of retinitis pigmentosa (RP). Since the cloning of the first USH gene (MYO7A) in 1995, there have been remarkable advances in elucidating the genetic basis for this disorder, as evidence for 11 distinct loci have been obtained and genes for 9 of them have been identified. The USH genes encode proteins of different classes and families, including motor proteins, scaffold proteins, cell adhesion molecules and transmembrane receptor proteins. Extensive information has emerged from mouse models and molecular studies regarding pathogenesis of this disorder and the wide phenotypic variation in both audiovestibular and/or visual function. A unifying hypothesis is that the USH proteins are integrated into a protein network that regulates hair bundle morphogenesis in the inner ear. This review addresses genetics and pathological mechanisms of USH. Understanding the molecular basis of phenotypic variation and pathogenesis of USH is important toward discovery of new molecular targets for diagnosis, prevention and treatment of this debilitating disorder.

Postmortem validation of breast density using dual-energy mammography

PubMed Central

Molloi, Sabee; Ducote, Justin L.; Ding, Huanjun; Feig, Stephen A.

2014-01-01

Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dual energy mammography system. Glandular and adipose equivalent phantoms of uniform thickness were used to calibrate a dual energy basis decomposition algorithm. Dual energy decomposition was applied after scatter correction to calculate breast density. Breast density was also estimated using radiologist reader assessment, standard histogram thresholding and a fuzzy C-mean algorithm. Chemical analysis was used as the reference standard to assess the accuracy of different techniques to measure breast composition. Results: Breast density measurements using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean algorithm, and dual energy were in good agreement with the measured fibroglandular volume fraction using chemical analysis. The standard error estimates using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean, and dual energy were 9.9%, 8.6%, 7.2%, and 4.7%, respectively. Conclusions: The results indicate that dual energy mammography can be used to accurately measure breast density. The variability in breast density estimation using dual energy mammography was lower than reader assessment rankings, standard histogram thresholding, and fuzzy C-mean algorithm. Improved quantification of breast density is expected to further enhance its utility as a risk factor for breast cancer. PMID:25086548

Postmortem validation of breast density using dual-energy mammography

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

Molloi, Sabee, E-mail: symolloi@uci.edu; Ducote, Justin L.; Ding, Huanjun

2014-08-15

Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dual energy mammography system. Glandular and adipose equivalent phantoms of uniform thickness were used to calibrate a dual energy basis decomposition algorithm. Dual energy decompositionmore » was applied after scatter correction to calculate breast density. Breast density was also estimated using radiologist reader assessment, standard histogram thresholding and a fuzzy C-mean algorithm. Chemical analysis was used as the reference standard to assess the accuracy of different techniques to measure breast composition. Results: Breast density measurements using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean algorithm, and dual energy were in good agreement with the measured fibroglandular volume fraction using chemical analysis. The standard error estimates using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean, and dual energy were 9.9%, 8.6%, 7.2%, and 4.7%, respectively. Conclusions: The results indicate that dual energy mammography can be used to accurately measure breast density. The variability in breast density estimation using dual energy mammography was lower than reader assessment rankings, standard histogram thresholding, and fuzzy C-mean algorithm. Improved quantification of breast density is expected to further enhance its utility as a risk factor for breast cancer.« less

Conceptualizing the impacts of dual practice on the retention of public sector specialists - evidence from South Africa.

PubMed

Ashmore, John; Gilson, Lucy

2015-01-19

'Dual practice', or multiple job holding, generally involves public sector-based health workers taking additional work in the private sector. This form of the practice is purported to help retain public health care workers in low and middle-income countries' public sectors through additional wage incentives. There has been little conceptual or empirical development of the relationship between dual practice and retention. This article helps begin to fill this gap, drawing on empirical evidence from a qualitative study focusing on South African specialists. Fifty-one repeat, in-depth interviews were carried out with 28 doctors (predominantly specialists) with more than one job, in one public and one private urban hospital. Findings suggest dual practice can impact both positively and negatively on specialists' intention to stay in the public sector. This is through multiple conceptual channels including those previously identified in the literature such as dual practice acting as a 'stepping stone' to private practice by reducing migration costs. Dual practice can also lead specialists to re-evaluate how they compare public and private jobs, and to overworking which can expedite decisions on whether to stay in the public sector or leave. Numerous respondents undertook dual practice without official permission. The idea that dual practice helps retain public specialists in South Africa may be overstated. Yet banning the practice may be ineffective, given many undertake it without permission in any case. Regulation should be better enforced to ensure dual practice is not abused. The conceptual framework developed in this article could form a basis for further qualitative and quantitative inquiry.

Low kV versus dual-energy virtual monoenergetic CT imaging for proven liver lesions: what are the advantages and trade-offs in conspicuity and image quality? A pilot study.

PubMed

Hanson, G Jay; Michalak, Gregory J; Childs, Robert; McCollough, Brian; Kurup, Anil N; Hough, David M; Frye, Judson M; Fidler, Jeff L; Venkatesh, Sudhakar K; Leng, Shuai; Yu, Lifeng; Halaweish, Ahmed F; Harmsen, W Scott; McCollough, Cynthia H; Fletcher, J G

2018-06-01

Single-energy low tube potential (SE-LTP) and dual-energy virtual monoenergetic (DE-VM) CT images both increase the conspicuity of hepatic lesions by increasing iodine signal. Our purpose was to compare the conspicuity of proven liver lesions, artifacts, and radiologist preferences in dose-matched SE-LTP and DE-VM images. Thirty-one patients with 72 proven liver lesions (21 benign, 51 malignant) underwent full-dose contrast-enhanced dual-energy CT (DECT). Half-dose images were obtained using single tube reconstruction of the dual-source SE-LTP projection data (80 or 100 kV), and by inserting noise into dual-energy projection data, with DE-VM images reconstructed from 40 to 70 keV. Three blinded gastrointestinal radiologists evaluated half-dose SE-LTP and DE-VM images, ranking and grading liver lesion conspicuity and diagnostic confidence (4-point scale) on a per-lesion basis. Image quality (noise, artifacts, sharpness) was evaluated, and overall image preference was ranked on per-patient basis. Lesion-to-liver contrast-to-noise ratio (CNR) was compared between techniques. Mean lesion size was 1.5 ± 1.2 cm. Across the readers, the mean conspicuity ratings for 40, 45, and 50 keV half-dose DE-VM images were superior compared to other half-dose image sets (p < 0.0001). Per-lesion diagnostic confidence was similar between half-dose SE-LTP compared to half-dose DE-VM images (p ≥ 0.05; 1.19 vs. 1.24-1.32). However, SE-LTP images had less noise and artifacts and were sharper compared to DE-VM images less than 70 keV (p < 0.05). On a per-patient basis, radiologists preferred SE-LTP images the most and preferred 40-50 keV the least (p < 0.0001). Lesion CNR was also higher in SE-LTP images than DE-VM images (p < 0.01). For the same applied dose level, liver lesions were more conspicuous using DE-VM compared to SE-LTP; however, SE-LTP images were preferred more than any single DE-VM energy level, likely due to lower noise and artifacts.

Turbine airfoil with dual wall formed from inner and outer layers separated by a compliant structure

DOEpatents

Campbell,; Christian X. , Morrison; Jay, A [Oviedo, FL

2011-12-20

A turbine airfoil usable in a turbine engine with a cooling system and a compliant dual wall configuration configured to enable thermal expansion between inner and outer layers while eliminating stress formation is disclosed. The compliant dual wall configuration may be formed a dual wall formed from inner and outer layers separated by a compliant structure. The compliant structure may be configured such that the outer layer may thermally expand without limitation by the inner layer. The compliant structure may be formed from a plurality of pedestals positioned generally parallel with each other. The pedestals may include a first foot attached to a first end of the pedestal and extending in a first direction aligned with the outer layer, and may include a second foot attached to a second end of the pedestal and extending in a second direction aligned with the inner layer.

Free radicals are present in human serum of Catha edulis Forsk (Khat) abusers.

PubMed

Al-Akwa, Ahmed A; Shaher, Monira; Al-Akwa, Sameeha; Aleryani, Samir L

2009-09-25

Khat (Catha edulis Forsk) is a naturally occurring drug with an amphetamine-like structure and action. It has been postulated that amphetamine induces free radical formation. On this basis, we have hypothesized that Khat may promote synthesis of reactive oxygen and nitrogen species in the same way that amphetamine promotes free radical production. Forty male subjects were enrolled in two groups: those with a chronic Khat chewing habit (n=20), and those without a chewing habit (controls; n=20). Both groups were matched with regard to age. Total antioxidant capacity and cholinesterase (AChE) activity were assayed. This study showed that Khat consumption inhibited serum free radical scavenging enzymes, resulting in significant elevations in free radical loads (p=0.01; n=20). We also showed that serum acetyl cholinesterase (AChE) was significantly inhibited in the Khat chewing group (p=0.002; n=20). These results show for the first time that Khat may contribute to high levels of free radicals. In addition, the presence of pesticides in Khat leaves is implicated in the inhibition of AChE activity.

Active faulting in the central Betic Cordillera (Spain): Palaeoseismological constraint of the surface-rupturing history of the Baza Fault (Central Betic Cordillera, Iberian Peninsula)

NASA Astrophysics Data System (ADS)

Castro, J.; Martin-Rojas, I.; Medina-Cascales, I.; García-Tortosa, F. J.; Alfaro, P.; Insua-Arévalo, J. M.

2018-06-01

This paper on the Baza Fault provides the first palaeoseismic data from trenches in the central sector of the Betic Cordillera (S Spain), one of the most tectonically active areas of the Iberian Peninsula. With the palaeoseismological data we constructed time-stratigraphic OxCal models that yield probability density functions (PDFs) of individual palaeoseismic event timing. We analysed PDF overlap to quantitatively correlate the walls and site events into a single earthquake chronology. We assembled a surface-rupturing history of the Baza Fault for the last ca. 45,000 years. We postulated six alternative surface rupturing histories including 8-9 fault-wide earthquakes. We calculated fault-wide earthquake recurrence intervals using Monte Carlo. This analysis yielded a 4750-5150 yr recurrence interval. Finally, compared our results with the results from empirical relationships. Our results will provide a basis for future analyses of more of other active normal faults in this region. Moreover, our results will be essential for improving earthquake-probability assessments in Spain, where palaeoseismic data are scarce.

Molecular biology of castration-resistant prostate cancer: basis for the novel therapeutic targets.

PubMed

Mellado, Begoña; Marin Aguilera, Mercedes; Pereira, Maria Veronica

2013-06-01

Prostate cancer cells express the androgen receptor (AR) and need the presence of androgens to survive. Androgen suppression is the gold standard first-line therapy for metastatic disease. Almost all prostate cancer patients initially respond to hormonal therapy, but most of them gradually develop castration-resistant progression. Recent evidence has shown that progression at the castration resistant prostate cancer (CRPC) stage is often mediated by AR signalling. Importantly, subsequent AR androgen inhibition, by abiraterone acetate or enzalutamide, has shown to improve patients' survival. Several mechanisms that enhance AR signalling in an androgen-depleted environment have been elucidated:(1) AR mutations that allow activation by low androgen levels or by other endogenous steroids, (2) AR amplification and/or overexpression,(3)increased local intracrine synthesis of androgens, (4) changes in AR cofactors and (5) cross-talk with cytokines and growth factors. Today, there are under development a number of novel agents targeting the AR signaling pathway. This article reviews the postulated mechanisms of AR-driven resistance to androgen suppression that have contributed to the development of new hormonal therapeutic strategies in prostate cancer.

Sulfuric acid in the Venus clouds.

NASA Technical Reports Server (NTRS)

Sill, G. T.

1972-01-01

The extremely dry nature of the Venus upper atmosphere appears to demand the presence of an efficient desiccating agent as the chief constituent of the clouds of Venus. On the basis of polarization measures it is to be expected that this substance is present as spherical droplets, 1 to 2 microns in diameter, with a refractive index n of 1.46 plus or minus 0.02 at 3500A in the observed region of the atmosphere, with T about equal to 235 K. This substance must have ultraviolet, visible, and infrared reflection properties not inconsistent with the observed spectrum of Venus. Sulfuric acid, of about 86% by weight composition, roughly fulfills the first of these properties. The visible and ultraviolet transmission features of a thin layer of elemental bromine and hydrobromic acid dissolved in sulfuric acid somewhat resemble the Venus spectrum, up to 14 microns. The chemical process postulated for forming sulfuric acid involves the oxidation of sulfur and its compounds to sulfuric acid through the agency of elemental bromine produced by the photolytic decomposition of hydrogen bromide.

On the stiffness matrix of the intervertebral joint: application to total disk replacement.

PubMed

O'Reilly, Oliver M; Metzger, Melodie F; Buckley, Jenni M; Moody, David A; Lotz, Jeffrey C

2009-08-01

The traditional method of establishing the stiffness matrix associated with an intervertebral joint is valid only for infinitesimal rotations, whereas the rotations featured in spinal motion are often finite. In the present paper, a new formulation of this stiffness matrix is presented, which is valid for finite rotations. This formulation uses Euler angles to parametrize the rotation, an associated basis, which is known as the dual Euler basis, to describe the moments, and it enables a characterization of the nonconservative nature of the joint caused by energy loss in the poroviscoelastic disk and ligamentous support structure. As an application of the formulation, the stiffness matrix of a motion segment is experimentally determined for the case of an intact intervertebral disk and compared with the matrices associated with the same segment after the insertion of a total disk replacement system. In this manner, the matrix is used to quantify the changes in the intervertebral kinetics associated with total disk replacements. As a result, this paper presents the first such characterization of the kinetics of a total disk replacement.

Quantum mechanics without the projection postulate and its realistic interpretation

NASA Astrophysics Data System (ADS)

Dieks, D.

1989-11-01

It is widely held that quantum mechanics is the first scientific theory to present scientifically internal, fundamental difficulties for a realistic interpretation (in the philosophical sense). The standard (Copenhagen) interpretation of the quantum theory is often described as the inevitable instrumentalistic response. It is the purpose of the present article to argue that quantum theory does not present fundamental new problems to a realistic interpretation. The formalism of quantum theory has the same states—it will be argued—as the formalisms of older physical theories and is capable of the same kinds of philosophical interpretation. This result is reached via an analysis of what it means to give a realistic interpretation to a theory. The main point of difference between quantum mechanics and other theories—as far as the possibilities of interpretation are concerned—is the special treatment given to measurement by the “projection postulate.” But it is possible to do without this postulate. Moreover, rejection of the projection postulate does not, in spite of what is often maintained in the literature, automatically lead to the many-worlds interpretation of quantum mechanics. A realistic interpretation is possible in which only the reality of one (our) world is recognized. It is argued that the Copenhagen interpretation as expounded by Bohr is not in conflict with the here proposed realistic interpretation of quantum theory.

Revisiting the Balazs thought experiment in the case of a left-handed material: electromagnetic-pulse-induced displacement of a dispersive, dissipative negative-index slab.

PubMed

Chau, Kenneth J; Lezec, Henri J

2012-04-23

We propose a set of postulates to describe the mechanical interaction between a plane-wave electromagnetic pulse and a dispersive, dissipative slab having a refractive index of arbitrary sign. The postulates include the Abraham electromagnetic momentum density, a generalized Lorentz force law, and a model for absorption-driven mass transfer from the pulse to the medium. These opto-mechanical mechanisms are incorporated into a one-dimensional finite-difference time-domain algorithm that solves Maxwell's equations and calculates the instantaneous force densities exerted by the pulse onto the slab, the momentum-per-unit-area of the pulse and slab, and the trajectories of the slab and system center-of-mass. We show that the postulates are consistent with conservation of global energy, momentum, and center-of-mass velocity at all times, even for cases in which the refractive index of the slab is negative or zero. Consistency between the set of postulates and well-established conservation laws reinforces the Abraham momentum density as the one true electromagnetic momentum density and enables, for the first time, identification of the correct form of the electromagnetic mass density distribution and development of an explicit model for mass transfer due to absorption, for the most general case of a ponderable medium that is both dispersive and dissipative. © 2012 Optical Society of America

Rayleigh imaging in spectral mammography

NASA Astrophysics Data System (ADS)

Berggren, Karl; Danielsson, Mats; Fredenberg, Erik

2016-03-01

Spectral imaging is the acquisition of multiple images of an object at different energy spectra. In mammography, dual-energy imaging (spectral imaging with two energy levels) has been investigated for several applications, in particular material decomposition, which allows for quantitative analysis of breast composition and quantitative contrast-enhanced imaging. Material decomposition with dual-energy imaging is based on the assumption that there are two dominant photon interaction effects that determine linear attenuation: the photoelectric effect and Compton scattering. This assumption limits the number of basis materials, i.e. the number of materials that are possible to differentiate between, to two. However, Rayleigh scattering may account for more than 10% of the linear attenuation in the mammography energy range. In this work, we show that a modified version of a scanning multi-slit spectral photon-counting mammography system is able to acquire three images at different spectra and can be used for triple-energy imaging. We further show that triple-energy imaging in combination with the efficient scatter rejection of the system enables measurement of Rayleigh scattering, which adds an additional energy dependency to the linear attenuation and enables material decomposition with three basis materials. Three available basis materials have the potential to improve virtually all applications of spectral imaging.

Developing ADHD in preschool: Testing the dual pathway model of temperament.

PubMed

Kerner Auch Koerner, Julia; Gust, Nicole; Petermann, Franz

2017-07-14

The dual pathway model of Attention Deficit Hyperactivity Disorder (ADHD) suggests that effortful control and positive approach, or surgency, are independent pathways leading to ADHD. This model has been proven on the basis of temperament in school children, however not in preschool children. In this study we tested whether the dual pathway model of ADHD can be replicated in preschool children using temperamental measures. One hundred and nineteen children (59 girls, M-age = 4.97 years, SD = 0.96) participated in a study. Parents rated temperament on the Child Behavior Questionnaire (CBQ) and parents and teachers rated ADHD symptoms (SDQ). We found that effortful control and surgency independently predicted preschool ADHD symptoms but there were no moderations or mediations. Our findings support the dual pathway model of temperament but not compensatory models of ADHD. Ratings of temperament might be an important predictor of which child is at risk to develop clinical ADHD later on and therefore an important part of prevention.

Construction of self-dual codes in the Rosenbloom-Tsfasman metric

NASA Astrophysics Data System (ADS)

Krisnawati, Vira Hari; Nisa, Anzi Lina Ukhtin

2017-12-01

Linear code is a very basic code and very useful in coding theory. Generally, linear code is a code over finite field in Hamming metric. Among the most interesting families of codes, the family of self-dual code is a very important one, because it is the best known error-correcting code. The concept of Hamming metric is develop into Rosenbloom-Tsfasman metric (RT-metric). The inner product in RT-metric is different from Euclid inner product that is used to define duality in Hamming metric. Most of the codes which are self-dual in Hamming metric are not so in RT-metric. And, generator matrix is very important to construct a code because it contains basis of the code. Therefore in this paper, we give some theorems and methods to construct self-dual codes in RT-metric by considering properties of the inner product and generator matrix. Also, we illustrate some examples for every kind of the construction.

On a Quantum Model of Brain Activities

NASA Astrophysics Data System (ADS)

Fichtner, K.-H.; Fichtner, L.; Freudenberg, W.; Ohya, M.

2010-01-01

One of the main activities of the brain is the recognition of signals. A first attempt to explain the process of recognition in terms of quantum statistics was given in [6]. Subsequently, details of the mathematical model were presented in a (still incomplete) series of papers (cf. [7, 2, 5, 10]). In the present note we want to give a general view of the principal ideas of this approach. We will introduce the basic spaces and justify the choice of spaces and operations. Further, we bring the model face to face with basic postulates any statistical model of the recognition process should fulfill. These postulates are in accordance with the opinion widely accepted in psychology and neurology.

First operation and effect of a new tandem-type ion source based on electron cyclotron resonance

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

Kato, Yushi, E-mail: kato@eei.eng.osaka-u.ac.jp; Kimura, Daiju; Yano, Keisuke

A new tandem type source has been constructed on the basis of electron cyclotron resonance plasma for producing synthesized ion beams in Osaka University. Magnetic field in the first stage consists of all permanent magnets, i.e., cylindrically comb shaped one, and that of the second stage consists of a pair of mirror coil, a supplemental coil and the octupole magnets. Both stage plasmas can be individually operated, and produced ions in which is energy controlled by large bore extractor also can be transported from the first to the second stage. We investigate the basic operation and effects of the tandemmore » type electron cyclotron resonance ion source (ECRIS). Analysis of ion beams and investigation of plasma parameters are conducted on produced plasmas in dual plasmas operation as well as each single operation. We describe construction and initial experimental results of the new tandem type ion source based on ECRIS with wide operation window for aiming at producing synthesized ion beams as this new source can be a universal source in future.« less

Evaluation and Characterization Study of Dual Pulse Laser-Induced Spark (DPLIS) for Rocket Engine Ignition System Application

NASA Technical Reports Server (NTRS)

Osborne, Robin; Wehrmeyer, Joseph; Trinh, Huu; Early, James

2003-01-01

This paper addresses the progress of technology development of a laser ignition system at NASA Marshall Space Flight Center (MSFC). Laser ignition has been used at MSFC in recent test series to successfully ignite RP1/GOX propellants in a subscale rocket chamber, and other past studies by NASA GRC have demonstrated the use of laser ignition for rocket engines. Despite the progress made in the study of this ignition method, the logistics of depositing laser sparks inside a rocket chamber have prohibited its use. However, recent advances in laser designs, the use of fiber optics, and studies of multi-pulse laser formats3 have renewed the interest of rocket designers in this state-of the-art technology which offers the potential elimination of torch igniter systems and their associated mechanical parts, as well as toxic hypergolic ignition systems. In support of this interest to develop an alternative ignition system that meets the risk-reduction demands of Next Generation Launch Technology (NGLT), characterization studies of a dual pulse laser format for laser-induced spark ignition are underway at MSFC. Results obtained at MSFC indicate that a dual pulse format can produce plasmas that absorb the laser energy as efficiently as a single pulse format, yet provide a longer plasma lifetime. In an experiments with lean H2/air propellants, the dual pulse laser format, containing the same total energy of a single laser pulse, produced a spark that was superior in its ability to provide sustained ignition of fuel-lean H2/air propellants. The results from these experiments are being used to optimize a dual pulse laser format for future subscale rocket chamber tests. Besides the ignition enhancement, the dual pulse technique provides a practical way to distribute and deliver laser light to the combustion chamber, an important consideration given the limitation of peak power that can be delivered through optical fibers. With this knowledge, scientists and engineers at Los Alamos National Laboratory and CFD Research Corporation have designed and fabricated a miniaturized, first-generation optical prototype of a laser ignition system that could be the basis for a laser ignition system for rocket applications. This prototype will be tested at MSFC in future subscale rocket ignition tests.

Molecular Determinants of the Thickened Matrix in a Dual-Species Pseudomonas aeruginosa and Enterococcus faecalis Biofilm

PubMed Central

Lee, Keehoon; Lee, Kang-Mu; Kim, Donggeun

2017-01-01

ABSTRACT Biofilms are microbial communities that inhabit various surfaces and are surrounded by extracellular matrices (ECMs). Clinical microbiologists have shown that the majority of chronic infections are caused by biofilms, following the introduction of the first biofilm infection model by J. W. Costerton and colleagues (J. Lam, R. Chan, K. Lam, and J. W. Costerton, Infect Immun 28:546–556, 1980). However, treatments for chronic biofilm infections are still limited to surgical removal of the infected sites. Pseudomonas aeruginosa and Enterococcus faecalis are two frequently identified bacterial species in biofilm infections; nevertheless, the interactions between these two species, especially during biofilm growth, are not clearly understood. In this study, we observed phenotypic changes in a dual-species biofilm of P. aeruginosa and E. faecalis, including a dramatic increase in biofilm matrix thickness. For clear elucidation of the spatial distribution of the dual-species biofilm, P. aeruginosa and E. faecalis were labeled with red and green fluorescence, respectively. E. faecalis was located at the lower part of the dual-species biofilm, while P. aeruginosa developed a structured biofilm on the upper part. Mutants with altered exopolysaccharide (EPS) productions were constructed in order to determine the molecular basis for the synergistic effect of the dual-species biofilm. Increased biofilm matrix thickness was associated with EPSs, not extracellular DNA. In particular, Pel and Psl contributed to interspecies and intraspecies interactions, respectively, in the dual-species P. aeruginosa and E. faecalis biofilm. Accordingly, targeting Pel and Psl might be an effective part of eradicating P. aeruginosa polymicrobial biofilms. IMPORTANCE Chronic infection is a serious problem in the medical field. Scientists have observed that chronic infections are closely associated with biofilms, and the vast majority of infection-causing biofilms are polymicrobial. Many studies have reported that microbes in polymicrobial biofilms interact with each other and that the bacterial interactions result in elevated virulence, in terms of factors, such as infectivity and antibiotic resistance. Pseudomonas aeruginosa and Enterococcus faecalis are frequently isolated pathogens in chronic biofilm infections. Nevertheless, while both bacteria are known to be agents of numerous nosocomial infections and can cause serious diseases, interactions between the bacteria in biofilms have rarely been examined. In this investigation, we aimed to characterize P. aeruginosa and E. faecalis dual-species biofilms and to determine the molecular factors that cause synergistic effects, especially on the matrix thickening of the biofilm. We suspect that our findings will contribute to the development of more efficient methods for eradicating polymicrobial biofilm infections. PMID:28842537

Molecular Determinants of the Thickened Matrix in a Dual-Species Pseudomonas aeruginosa and Enterococcus faecalis Biofilm.

PubMed

Lee, Keehoon; Lee, Kang-Mu; Kim, Donggeun; Yoon, Sang Sun

2017-11-01

Biofilms are microbial communities that inhabit various surfaces and are surrounded by extracellular matrices (ECMs). Clinical microbiologists have shown that the majority of chronic infections are caused by biofilms, following the introduction of the first biofilm infection model by J. W. Costerton and colleagues (J. Lam, R. Chan, K. Lam, and J. W. Costerton, Infect Immun 28:546-556, 1980). However, treatments for chronic biofilm infections are still limited to surgical removal of the infected sites. Pseudomonas aeruginosa and Enterococcus faecalis are two frequently identified bacterial species in biofilm infections; nevertheless, the interactions between these two species, especially during biofilm growth, are not clearly understood. In this study, we observed phenotypic changes in a dual-species biofilm of P. aeruginosa and E. faecalis , including a dramatic increase in biofilm matrix thickness. For clear elucidation of the spatial distribution of the dual-species biofilm, P. aeruginosa and E. faecalis were labeled with red and green fluorescence, respectively. E. faecalis was located at the lower part of the dual-species biofilm, while P. aeruginosa developed a structured biofilm on the upper part. Mutants with altered exopolysaccharide (EPS) productions were constructed in order to determine the molecular basis for the synergistic effect of the dual-species biofilm. Increased biofilm matrix thickness was associated with EPSs, not extracellular DNA. In particular, Pel and Psl contributed to interspecies and intraspecies interactions, respectively, in the dual-species P. aeruginosa and E. faecalis biofilm. Accordingly, targeting Pel and Psl might be an effective part of eradicating P. aeruginosa polymicrobial biofilms. IMPORTANCE Chronic infection is a serious problem in the medical field. Scientists have observed that chronic infections are closely associated with biofilms, and the vast majority of infection-causing biofilms are polymicrobial. Many studies have reported that microbes in polymicrobial biofilms interact with each other and that the bacterial interactions result in elevated virulence, in terms of factors, such as infectivity and antibiotic resistance. Pseudomonas aeruginosa and Enterococcus faecalis are frequently isolated pathogens in chronic biofilm infections. Nevertheless, while both bacteria are known to be agents of numerous nosocomial infections and can cause serious diseases, interactions between the bacteria in biofilms have rarely been examined. In this investigation, we aimed to characterize P. aeruginosa and E. faecalis dual-species biofilms and to determine the molecular factors that cause synergistic effects, especially on the matrix thickening of the biofilm. We suspect that our findings will contribute to the development of more efficient methods for eradicating polymicrobial biofilm infections. Copyright © 2017 American Society for Microbiology.

Dual-process models of health-related behaviour and cognition: a review of theory.

PubMed

Houlihan, S

2018-03-01

The aim of this review was to synthesise a spectrum of theories incorporating dual-process models of health-related behaviour. Review of theory, adapted loosely from Cochrane-style systematic review methodology. Inclusion criteria were specified to identify all relevant dual-process models that explain decision-making in the context of decisions made about human health. Data analysis took the form of iterative template analysis (adapted from the conceptual synthesis framework used in other reviews of theory), and in this way theories were synthesised on the basis of shared theoretical constructs and causal pathways. Analysis and synthesis proceeded in turn, instead of moving uni-directionally from analysis of individual theories to synthesis of multiple theories. Namely, the reviewer considered and reconsidered individual theories and theoretical components in generating the narrative synthesis' main findings. Drawing on systematic review methodology, 11 electronic databases were searched for relevant dual-process theories. After de-duplication, 12,198 records remained. Screening of title and abstract led to the exclusion of 12,036 records, after which 162 full-text records were assessed. Of those, 21 records were included in the review. Moving back and forth between analysis of individual theories and the synthesis of theories grouped on the basis of theme or focus yielded additional insights into the orientation of a theory to an individual. Theories could be grouped in part on their treatment of an individual as an irrational actor, as social actor, as actor in a physical environment or as a self-regulated actor. Synthesising identified theories into a general dual-process model of health-related behaviour indicated that such behaviour is the result of both propositional and unconscious reasoning driven by an individual's response to internal cues (such as heuristics, attitude and affect), physical cues (social and physical environmental stimuli) as well as regulating factors (such as habit) that mediate between them. Copyright © 2017. Published by Elsevier Ltd.

From railway spine to whiplash--the recycling of nervous irritation.

PubMed

Ferrari, Robert; Shorter, Edward

2003-11-01

The search for a specific structural basis for chronic whiplash and other chronic pain and fatigue syndromes has been in progress for decades, and yet currently there remains no "structural" solution to these enigmata. In light of the failure of research to identify the chronic "damage" or pathology as lying in a muscular, bony, or "connective tissue" sites for many chronic pain syndromes like whiplash, fibromyalgia, et cetera, more recent attention has been paid to nervous system structures. Nerve irritation has been implicated as the basis for the pain and other symptoms that are common to many chronic disability syndromes. We postulate here, however, that the concept of nervous irritation has been prostituted for centuries whenever more concrete structural explanations for chronic pain and other controversial illness have been untenable. We suggest that, after each cycle of nervous irritation as a disease, and subsequent dismissal of the notion, the doctrine of irritation as a disease was too good to go away. First, with the hypersthenic and asthenic diseases of the nineteenth century, then railway spine, whiplash, thoracic outlet syndrome, and now brachial plexus irritation, we detect the same pattern: patients with symptoms, but no objective evidence of nerve disease. Nervous irritation has repeatedly served this purpose for the last 200 years. It is our intent that bringing an understanding of this trend will encourage current clinicians and researchers to appreciate the need to abandon this form of speculation without historical insight when dealing with today's controversial syndromes.

Demonstration of 1024x1024 pixel dual-band QWIP focal plane array

NASA Astrophysics Data System (ADS)

Gunapala, S. D.; Bandara, S. V.; Liu, J. K.; Mumolo, J. M.; Ting, D. Z.; Hill, C. J.; Nguyen, J.; Rafol, S. B.

2010-04-01

QWIPs are well known for their stability, high pixel-pixel uniformity and high pixel operability which are quintessential parameters for large area imaging arrays. In this paper we report the first demonstration of the megapixel-simultaneously-readable and pixel-co-registered dual-band QWIP focal plane array (FPA). The dual-band QWIP device was developed by stacking two multi-quantum-well stacks tuned to absorb two different infrared wavelengths. The full width at half maximum (FWHM) of the mid-wave infrared (MWIR) band extends from 4.4 - 5.1 μm and FWHM of the long-wave infrared (LWIR) band extends from 7.8 - 8.8 μm. Dual-band QWIP detector arrays were hybridized with direct injection 30 μm pixel pitch megapixel dual-band simultaneously readable CMOS read out integrated circuits using the indium bump hybridization technique. The initial dual-band megapixel QWIP FPAs were cooled to 68K operating temperature. The preliminary data taken from the first megapixel QWIP FPA has shown system NE▵T of 27 and 40 mK for MWIR and LWIR bands respectively.

Mortality salience and morality: thinking about death makes people less utilitarian.

PubMed

Trémolière, Bastien; Neys, Wim De; Bonnefon, Jean-François

2012-09-01

According to the dual-process model of moral judgment, utilitarian responses to moral conflict draw on limited cognitive resources. Terror Management Theory, in parallel, postulates that mortality salience mobilizes these resources to suppress thoughts of death out of focal attention. Consequently, we predicted that individuals under mortality salience would be less likely to give utilitarian responses to moral conflicts. Two experiments corroborated this hypothesis. Experiment 1 showed that utilitarian responses to non-lethal harm conflicts were less frequent when participants were reminded of their mortality. Experiment 2 showed that the detrimental effect of mortality salience on utilitarian conflict judgments was comparable to that of an extreme concurrent cognitive load. These findings raise the question of whether private judgment and public debate about controversial moral issues might be shaped by mortality salience effects, since these issues (e.g., assisted suicide) often involve matters of life and death. Copyright © 2012 Elsevier B.V. All rights reserved.

How the bimodal format of presentation affects working memory: an overview.

PubMed

Mastroberardino, Serena; Santangelo, Valerio; Botta, Fabiano; Marucci, Francesco S; Olivetti Belardinelli, Marta

2008-03-01

The best format in which information that has to be recalled is presented has been investigated in several studies, which focused on the impact of bimodal stimulation on working memory performance. An enhancement of participant's performance in terms of correct recall has been repeatedly found, when bimodal formats of presentation (i.e., audiovisual) were compared to unimodal formats (i.e, either visual or auditory), in providing implications for multimedial learning. Several theoretical frameworks have been suggested in order to account for the bimodal advantage, ranging from those emphasizing early stages of processing (such as automatic alerting effects or multisensory integration processes) to those centred on late stages of processing (as postulated by the dual coding theory). The aim of this paper is to review previous contributions to this topic, providing a comprehensive theoretical framework, which is updated by the latest empirical studies.

Efficient Kill-Save Ratios Ease Up the Cognitive Demands on Counterintuitive Moral Utilitarianism.

PubMed

Trémolière, Bastien; Bonnefon, Jean-François

2014-07-01

The dual-process model of moral judgment postulates that utilitarian responses to moral dilemmas (e.g., accepting to kill one to save five) are demanding of cognitive resources. Here we show that utilitarian responses can become effortless, even when they involve to kill someone, as long as the kill-save ratio is efficient (e.g., 1 is killed to save 500). In Experiment 1, participants responded to moral dilemmas featuring different kill-save ratios under high or low cognitive load. In Experiments 2 and 3, participants responded at their own pace or under time pressure. Efficient kill-save ratios promoted utilitarian responding and neutered the effect of load or time pressure. We discuss whether this effect is more easily explained by a parallel-activation model or by a default-interventionist model. © 2014 by the Society for Personality and Social Psychology, Inc.

Comparison of Dynamic Contrast Enhanced MRI and Quantitative SPECT in a Rat Glioma Model

PubMed Central

Skinner, Jack T.; Yankeelov, Thomas E.; Peterson, Todd E.; Does, Mark D.

2012-01-01

Pharmacokinetic modeling of dynamic contrast enhanced (DCE)-MRI data provides measures of the extracellular volume fraction (ve) and the volume transfer constant (Ktrans) in a given tissue. These parameter estimates may be biased, however, by confounding issues such as contrast agent and tissue water dynamics, or assumptions of vascularization and perfusion made by the commonly used model. In contrast to MRI, radiotracer imaging with SPECT is insensitive to water dynamics. A quantitative dual-isotope SPECT technique was developed to obtain an estimate of ve in a rat glioma model for comparison to the corresponding estimates obtained using DCE-MRI with a vascular input function (VIF) and reference region model (RR). Both DCE-MRI methods produced consistently larger estimates of ve in comparison to the SPECT estimates, and several experimental sources were postulated to contribute to these differences. PMID:22991315

Symmetry as Bias: Rediscovering Special Relativity

NASA Technical Reports Server (NTRS)

Lowry, Michael R.

1992-01-01

This paper describes a rational reconstruction of Einstein's discovery of special relativity, validated through an implementation: the Erlanger program. Einstein's discovery of special relativity revolutionized both the content of physics and the research strategy used by theoretical physicists. This research strategy entails a mutual bootstrapping process between a hypothesis space for biases, defined through different postulated symmetries of the universe, and a hypothesis space for physical theories. The invariance principle mutually constrains these two spaces. The invariance principle enables detecting when an evolving physical theory becomes inconsistent with its bias, and also when the biases for theories describing different phenomena are inconsistent. Structural properties of the invariance principle facilitate generating a new bias when an inconsistency is detected. After a new bias is generated. this principle facilitates reformulating the old, inconsistent theory by treating the latter as a limiting approximation. The structural properties of the invariance principle can be suitably generalized to other types of biases to enable primal-dual learning.

Photonic Choke-Joints for Dual Polarization Waveguides

NASA Technical Reports Server (NTRS)

Wollack, Edward J. (Inventor); U-Yen, Kongpop (Inventor); Chuss, David T. (Inventor)

2014-01-01

A waveguide structure for a dual polarization waveguide includes a first flange member, a second flange member, and a waveguide member disposed in each of the first flange member and second flange member. The first flange member and the second flange member are configured to be coupled together in a spaced-apart relationship separated by a gap. The first flange member has a substantially smooth surface, and the second flange member has an array of two-dimensional pillar structures formed therein.

WE-D-BRF-05: Quantitative Dual-Energy CT Imaging for Proton Stopping Power Computation

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

Han, D; Williamson, J; Siebers, J

2014-06-15

Purpose: To extend the two-parameter separable basis-vector model (BVM) to estimation of proton stopping power from dual-energy CT (DECT) imaging. Methods: BVM assumes that the photon cross sections of any unknown material can be represented as a linear combination of the corresponding quantities for two bracketing basis materials. We show that both the electron density (ρe) and mean excitation energy (Iex) can be modeled by BVM, enabling stopping power to be estimated from the Bethe-Bloch equation. We have implemented an idealized post-processing dual energy imaging (pDECT) simulation consisting of monogenetic 45 keV and 80 keV scanning beams with polystyrene-water andmore » water-CaCl2 solution basis pairs for soft tissues and bony tissues, respectively. The coefficients of 24 standard ICRU tissue compositions were estimated by pDECT. The corresponding ρe, Iex, and stopping power tables were evaluated via BVM and compared to tabulated ICRU 44 reference values. Results: BVM-based pDECT was found to estimate ρe and Iex with average and maximum errors of 0.5% and 2%, respectively, for the 24 tissues. Proton stopping power values at 175 MeV, show average/maximum errors of 0.8%/1.4%. For adipose, muscle and bone, these errors result range prediction accuracies less than 1%. Conclusion: A new two-parameter separable DECT model (BVM) for estimating proton stopping power was developed. Compared to competing parametric fit DECT models, BVM has the comparable prediction accuracy without necessitating iterative solution of nonlinear equations or a sample-dependent empirical relationship between effective atomic number and Iex. Based on the proton BVM, an efficient iterative statistical DECT reconstruction model is under development.« less

Dual redundant arm system operational quality measures and their applications - Static measures

NASA Technical Reports Server (NTRS)

Lee, Sukhan; Kim, Sungbok

1990-01-01

The authors present dual-arm system static operational quality measures which quantify the efficiency and capability of a dual-arm system in generating Cartesian velocities and static forces. First, they define and analyze the kinematic interactions between the two arms incurred by the various modes of dual-arm cooperation, such as transport, assembly, and grasping modes of cooperation, and specify the kinematic constraints imposed on individual arms in Cartesian space due to the kinematic interactions. Dual-arm static manipulability is presented. Finally, dual-arm operational quality is scaled by a task-oriented operational quality measure (TOQs) obtained by the comparison between the desired and actual static manipulabilities. TOQs is used in the optimization of dual-arm joint configurations. Simulation results are shown.

[Research of dual-photoelastic-modulator-based beat frequency modulation and Fourier-Bessel transform imaging spectrometer].

PubMed

Wang, Zhi-Bin; Zhang, Rui; Wang, Yao-Li; Huang, Yan-Fei; Chen, You-Hua; Wang, Li-Fu; Yang, Qiang

2014-02-01

As the existing photoelastic-modulator(PEM) modulating frequency in the tens of kHz to hundreds of kHz between, leading to frequency of modulated interference signal is higher, so ordinary array detector cannot effectively caprure interference signal..A new beat frequency modulation method based on dual-photoelastic-modulator (Dual-PEM) and Fourier-Bessel transform is proposed as an key component of dual-photoelastic-modulator-based imaging spectrometer (Dual-PEM-IS) combined with charge coupled device (CCD). The dual-PEM are operated as an electro-optic circular retardance modulator, Operating the PEMs at slightly different resonant frequencies w1 and w2 respectively, generates a differential signal at a much lower heterodyne frequency that modulates the incident light. This method not only retains the advantages of the existing PEM, but also the frequency of modulated photocurrent decreased by 2-3 orders of magnitude (10-500 Hz) and can be detected by common array detector, and the incident light spectra can be obtained by Fourier-Bessel transform of low frequency component in the modulated signal. The method makes the PEM has the dual capability of imaging and spectral measurement. The basic principle is introduced, the basic equations is derived, and the feasibility is verified through the corresponding numerical simulation and experiment. This method has' potential applications in imaging spectrometer technology, and analysis of the effect of deviation of the optical path difference. This work provides the necessary theoretical basis for remote sensing of new Dual-PEM-IS and for engineering implementation of spectra inversion.

Decentralized Sliding Mode Observer Based Dual Closed-Loop Fault Tolerant Control for Reconfigurable Manipulator against Actuator Failure.

PubMed

Zhao, Bo; Li, Chenghao; Liu, Derong; Li, Yuanchun

2015-01-01

This paper considers a decentralized fault tolerant control (DFTC) scheme for reconfigurable manipulators. With the appearance of norm-bounded failure, a dual closed-loop trajectory tracking control algorithm is proposed on the basis of the Lyapunov stability theory. Characterized by the modularization property, the actuator failure is estimated by the proposed decentralized sliding mode observer (DSMO). Moreover, the actuator failure can be treated in view of the local joint information, so its control performance degradation is independent of other normal joints. In addition, the presented DFTC scheme is significantly simplified in terms of the structure of the controller due to its dual closed-loop architecture, and its feasibility is highly reflected in the control of reconfigurable manipulators. Finally, the effectiveness of the proposed DFTC scheme is demonstrated using simulations.

Decentralized Sliding Mode Observer Based Dual Closed-Loop Fault Tolerant Control for Reconfigurable Manipulator against Actuator Failure

PubMed Central

Zhao, Bo; Li, Yuanchun

2015-01-01

This paper considers a decentralized fault tolerant control (DFTC) scheme for reconfigurable manipulators. With the appearance of norm-bounded failure, a dual closed-loop trajectory tracking control algorithm is proposed on the basis of the Lyapunov stability theory. Characterized by the modularization property, the actuator failure is estimated by the proposed decentralized sliding mode observer (DSMO). Moreover, the actuator failure can be treated in view of the local joint information, so its control performance degradation is independent of other normal joints. In addition, the presented DFTC scheme is significantly simplified in terms of the structure of the controller due to its dual closed-loop architecture, and its feasibility is highly reflected in the control of reconfigurable manipulators. Finally, the effectiveness of the proposed DFTC scheme is demonstrated using simulations. PMID:26181826

Non Abelian T-duality in Gauged Linear Sigma Models

NASA Astrophysics Data System (ADS)

Bizet, Nana Cabo; Martínez-Merino, Aldo; Zayas, Leopoldo A. Pando; Santos-Silva, Roberto

2018-04-01

Abelian T-duality in Gauged Linear Sigma Models (GLSM) forms the basis of the physical understanding of Mirror Symmetry as presented by Hori and Vafa. We consider an alternative formulation of Abelian T-duality on GLSM's as a gauging of a global U(1) symmetry with the addition of appropriate Lagrange multipliers. For GLSMs with Abelian gauge groups and without superpotential we reproduce the dual models introduced by Hori and Vafa. We extend the construction to formulate non-Abelian T-duality on GLSMs with global non-Abelian symmetries. The equations of motion that lead to the dual model are obtained for a general group, they depend in general on semi-chiral superfields; for cases such as SU(2) they depend on twisted chiral superfields. We solve the equations of motion for an SU(2) gauged group with a choice of a particular Lie algebra direction of the vector superfield. This direction covers a non-Abelian sector that can be described by a family of Abelian dualities. The dual model Lagrangian depends on twisted chiral superfields and a twisted superpotential is generated. We explore some non-perturbative aspects by making an Ansatz for the instanton corrections in the dual theories. We verify that the effective potential for the U(1) field strength in a fixed configuration on the original theory matches the one of the dual theory. Imposing restrictions on the vector superfield, more general non-Abelian dual models are obtained. We analyze the dual models via the geometry of their susy vacua.

Algorithm-enabled partial-angular-scan configurations for dual-energy CT.

PubMed

Chen, Buxin; Zhang, Zheng; Xia, Dan; Sidky, Emil Y; Pan, Xiaochuan

2018-05-01

We seek to investigate an optimization-based one-step method for image reconstruction that explicitly compensates for nonlinear spectral response (i.e., the beam-hardening effect) in dual-energy CT, to investigate the feasibility of the one-step method for enabling two dual-energy partial-angular-scan configurations, referred to as the short- and half-scan configurations, on standard CT scanners without involving additional hardware, and to investigate the potential of the short- and half-scan configurations in reducing imaging dose and scan time in a single-kVp-switch full-scan configuration in which two full rotations are made for collection of dual-energy data. We use the one-step method to reconstruct images directly from dual-energy data through solving a nonconvex optimization program that specifies the images to be reconstructed in dual-energy CT. Dual-energy full-scan data are generated from numerical phantoms and collected from physical phantoms with the standard single-kVp-switch full-scan configuration, whereas dual-energy short- and half-scan data are extracted from the corresponding full-scan data. Besides visual inspection and profile-plot comparison, the reconstructed images are analyzed also in quantitative studies based upon tasks of linear-attenuation-coefficient and material-concentration estimation and of material differentiation. Following the performance of a computer-simulation study to verify that the one-step method can reconstruct numerically accurately basis and monochromatic images of numerical phantoms, we reconstruct basis and monochromatic images by using the one-step method from real data of physical phantoms collected with the full-, short-, and half-scan configurations. Subjective inspection based upon visualization and profile-plot comparison reveals that monochromatic images, which are used often in practical applications, reconstructed from the full-, short-, and half-scan data are largely visually comparable except for some differences in texture details. Moreover, quantitative studies based upon tasks of linear-attenuation-coefficient and material-concentration estimation and of material differentiation indicate that the short- and half-scan configurations yield results in close agreement with the ground-truth information and that of the full-scan configuration. The one-step method considered can compensate effectively for the nonlinear spectral response in full- and partial-angular-scan dual-energy CT. It can be exploited for enabling partial-angular-scan configurations on standard CT scanner without involving additional hardware. Visual inspection and quantitative studies reveal that, with the one-step method, partial-angular-scan configurations considered can perform at a level comparable to that of the full-scan configuration, thus suggesting the potential of the two partial-angular-scan configurations in reducing imaging dose and scan time in the standard single-kVp-switch full-scan CT in which two full rotations are performed. The work also yields insights into the investigation and design of other nonstandard scan configurations of potential practical significance in dual-energy CT. © 2018 American Association of Physicists in Medicine.

Method for continuously recovering metals using a dual zone chemical reactor

DOEpatents

Bronson, Mark C.

1995-01-01

A dual zone chemical reactor continuously processes metal-containing materials while regenerating and circulating a liquid carrier. The starting materials are fed into a first reaction zone of a vessel containing a molten salt carrier. The starting materials react to form a metal product and a by-product that dissolves in the molten salt that flows to a second reaction zone in the reaction vessel. The second reaction zone is partitioned from, but in fluid communication with, the first reaction zone. The liquid carrier continuously circulates along a pathway between the first reaction zone and the second reaction zone. A reactive gas is introduced into the second reaction zone to react with the reaction by-product to generate the molten salt. The metal product, the gaseous waste products, and the excess liquid carrier are removed without interrupting the operation of the reactor. The design of the dual zone reactor can be adapted to combine a plurality of liquid carrier regeneration zones in a multiple dual zone chemical reactor for production scale processing.

The evolution of cognitive behavior therapy for schizophrenia: current practice and recent developments.

PubMed

Tai, Sara; Turkington, Douglas

2009-09-01

Cognitive behavior therapy (CBT) evolved from behavioral theory and developed to focus more on cognitive models that incorporated reappraisal of thinking errors and schema change strategies. This article will describe the key elements of CBT for schizophrenia and the current evidence of its efficacy and effectiveness. We conclude with a description of recent concepts that extend the theoretical basis of practice and expand the range of CBT strategies for use in schizophrenia. Mindfulness, meta-cognitive approaches, compassionate mind training, and method of levels are postulated as useful adjuncts for CBT with psychotic patients.

[Christian Wolff (1679-1754) and the medical concept of his time].

PubMed

Kaiser, W

1979-06-01

The 300th anniversary of the birthday of Christian Wolff gave the occasion to set his multilateral work in relation to the medical currents of his time and to analyse it from the standpoint of modern medicine. Especially in his early period at Halle University Christian Wolff develops a new research programme with essential accents for the future physician. His philosophical literature with the postulates containing in this are conformable to the aim of the predecessors of the French revolution and on the sector of the art of therapeutic forms the basis decisive improvements in organised public health.

The Evolution of Cognitive Behavior Therapy for Schizophrenia: Current Practice and Recent Developments

PubMed Central

Tai, Sara; Turkington, Douglas

2009-01-01

Cognitive behavior therapy (CBT) evolved from behavioral theory and developed to focus more on cognitive models that incorporated reappraisal of thinking errors and schema change strategies. This article will describe the key elements of CBT for schizophrenia and the current evidence of its efficacy and effectiveness. We conclude with a description of recent concepts that extend the theoretical basis of practice and expand the range of CBT strategies for use in schizophrenia. Mindfulness, meta-cognitive approaches, compassionate mind training, and method of levels are postulated as useful adjuncts for CBT with psychotic patients. PMID:19661198

A note on the problem of choosing a model of the universe. II

NASA Astrophysics Data System (ADS)

Skalsky, Vladimir

1989-05-01

The value of the mean mass density (rho) of the universe is examined. It is shown that there is a difference between the present terrestrial conditions and the initial conditions of the universe expansion and that, for the sphere of the physical boundary conditions represented by Planck's values (when the present evolution phase of the universe was probably decided), there are serious limitations for the value of rho. It is postulated on the basis of these limiting conditions that some cause may exist for which the condition corresponding to the critical mass density of the universe was realized.

Dual Check Valve and Method of Controlling Flow Through the Same

NASA Technical Reports Server (NTRS)

Corallo, Roger (Inventor)

2016-01-01

A dual check valve includes, a housing having a cavity fluidically connecting three ports, a movable member movably engaged within the cavity from at least a first position occluding a first port of the three ports, a second position occluding a second port of the three ports, and a third position allowing flow between both the first port, the second port and a third port of the three ports.

Dual aperture dipole magnet with second harmonic component

DOEpatents

Praeg, Walter F.

1985-01-01

An improved dual aperture dipole electromagnet includes a second-harmonic frequency magnetic guide field winding which surrounds first harmonic frequency magnetic guide field windings associated with each aperture. The second harmonic winding and the first harmonic windings cooperate to produce resultant magnetic waveforms in the apertures which have extended acceleration and shortened reset portions of electromagnet operation.

The TACT-Mentor Program: A Dual Introduction into College Teaching. Final Report.

ERIC Educational Resources Information Center

Murray, Robert C.

A two-part effort called "The TACT Mentor Program: A Dual Introduction into College Teaching," designed to assist new faculty in their first year of teaching at Heidelberg College, Ohio, is described and evaluated. The first part of the program, TACT (Teachers and College Teaching) consisted of weekly discussions based on the book…

Dual aperture dipole magnet with second harmonic component

DOEpatents

Praeg, W.F.

1983-08-31

An improved dual aperture dipole electromagnet includes a second-harmonic frequency magnetic guide field winding which surrounds first harmonic frequency magnetic guide field windings associated with each aperture. The second harmonic winding and the first harmonic windings cooperate to produce resultant magnetic waveforms in the apertures which have extended acceleration and shortened reset portions of electromagnet operation.

Symbolic play and language development.

PubMed

Orr, Edna; Geva, Ronny

2015-02-01

Symbolic play and language are known to be highly interrelated, but the developmental process involved in this relationship is not clear. Three hypothetical paths were postulated to explore how play and language drive each other: (1) direct paths, whereby initiation of basic forms in symbolic action or babbling, will be directly related to all later emerging language and motor outputs; (2) an indirect interactive path, whereby basic forms in symbolic action will be associated with more complex forms in symbolic play, as well as with babbling, and babbling mediates the relationship between symbolic play and speech; and (3) a dual path, whereby basic forms in symbolic play will be associated with basic forms of language, and complex forms of symbolic play will be associated with complex forms of language. We micro-coded 288 symbolic vignettes gathered during a yearlong prospective bi-weekly examination (N=14; from 6 to 18 months of age). Results showed that the age of initiation of single-object symbolic play correlates strongly with the age of initiation of later-emerging symbolic and vocal outputs; its frequency at initiation is correlated with frequency at initiation of babbling, later-emerging speech, and multi-object play in initiation. Results support the notion that a single-object play relates to the development of other symbolic forms via a direct relationship and an indirect relationship, rather than a dual-path hypothesis. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Increased functional connectivity in the ventral and dorsal streams during retrieval of novel words in professional musicians.

PubMed

Dittinger, Eva; Valizadeh, Seyed Abolfazl; Jäncke, Lutz; Besson, Mireille; Elmer, Stefan

2018-02-01

Current models of speech and language processing postulate the involvement of two parallel processing streams (the dual stream model): a ventral stream involved in mapping sensory and phonological representations onto lexical and conceptual representations and a dorsal stream contributing to sound-to-motor mapping, articulation, and to how verbal information is encoded and manipulated in memory. Based on previous evidence showing that music training has an influence on language processing, cognitive functions, and word learning, we examined EEG-based intracranial functional connectivity in the ventral and dorsal streams while musicians and nonmusicians learned the meaning of novel words through picture-word associations. In accordance with the dual stream model, word learning was generally associated with increased beta functional connectivity in the ventral stream compared to the dorsal stream. In addition, in the linguistically most demanding "semantic task," musicians outperformed nonmusicians, and this behavioral advantage was accompanied by increased left-hemispheric theta connectivity in both streams. Moreover, theta coherence in the left dorsal pathway was positively correlated with the number of years of music training. These results provide evidence for a complex interplay within a network of brain regions involved in semantic processing and verbal memory functions, and suggest that intensive music training can modify its functional architecture leading to advantages in novel word learning. © 2017 Wiley Periodicals, Inc.

Sequence analysis of the 5.8S ribosomal DNA and internal transcribed spacers (ITS1 and ITS2) from five species of the Oxalis tuberosa alliance.

PubMed

Tosto, D S; Hopp, H E

1996-01-01

The internal transcribed spacer region (ITS1 and ITS2) of the 18S-25S nuclear ribosomal DNA sequence and the intervening 5.8S region from five species of the genus Oxalis was amplified by polymerase chain reaction and subjected to direct DNA sequencing. On the basis of cytogenetic studies some species of this genus were postulated to be related by the number of chromosomes. Sequence homologies in the ITS1, 5.8S and ITS2 among species are in good agreement with previous relationships established on the basis of chromosome numbers. We also identified a highly conserved sequence of six bp in the ITS1, reported to be present in a wide range of flowering plants, but not in the Oxalidaceae family to which the genus Oxalis belongs to.

Comparison of High School Dual-Enrollment and Traditional First-Term General/Organic/Biochemistry College Chemistry Class Outcomes

ERIC Educational Resources Information Center

Zuidema, Daniel R.; Eames, Kevin J.

2014-01-01

Student performance in a high school dual-enrollment chemistry course was compared with student performance in the corresponding traditional college course. The two courses were taught by the same instructor and evaluated using the same American Chemical Society (ACS) standardized examination. Interestingly, the high school dual-enrollment…

Investigating Perfect Timesharing: The Relationship between IM-Compatible Tasks and Dual-Task Performance

ERIC Educational Resources Information Center

Halvorson, Kimberly M.; Ebner, Herschel; Hazeltine, Eliot

2013-01-01

Why are dual-task costs reduced with ideomotor (IM) compatible tasks (Greenwald & Shulman, 1973; Lien, Proctor & Allen, 2002)? In the present experiments, we first examine three different measures of single-task performance (pure single-task blocks, mixed blocks, and long stimulus onset asynchrony [SOA] trials in dual-task blocks) and two…

Cholinesterase inhibitor (Altenuene) from an endophytic fungus Alternaria alternata: optimization, purification and characterization.

PubMed

Bhagat, J; Kaur, A; Kaur, R; Yadav, A K; Sharma, V; Chadha, B S

2016-10-01

The aim of this study was to screen endophytic fungi isolated from Vinca rosea for their potential to produce acetylcholinesterase (AChE) inhibitors. Endophytic fungi isolated from V. rosea (Catharanthus roseus), were screened for AChE inhibitor production using Ellman's method. Maximum inhibition against AChE (78%) was observed in an isolate VS-10, identified to be Alternaria alternata on morphological and molecular basis. The isolate also inhibited butyrylcholinesterase (73%). Significant increase (1·3 fold) was achieved after optimization of process parameters using one variable at time approach. The inhibitor was purified using chromatographic techniques. The structure elucidation of the inhibitor was carried out using spectroscopic techniques and was identified to be 'altenuene'. The purified inhibitor possessed antioxidant potential as revealed by dot blot assay. The insecticidal potential of purified inhibitor was evaluated by feeding Spodoptora litura on diet amended with inhibitor. It evinced significant larval mortality. Endophytic A. alternata can serve as a source of dual cholinesterase inhibitor 'altenuene' with significant antioxidant and insecticidal activity. This is the first report on acetylcholinestearse inhibitory activity of altenuene. Alternaria alternata has the potential to produce a dual ChE inhibitor with antioxidant activity useful in the treatment of neurodegenerative disorders and in agriculture as biocontrol agent. © 2016 The Society for Applied Microbiology.

Dual salt precipitation for the recovery of a recombinant protein from Escherichia coli.

PubMed

Balasundaram, Bangaru; Sachdeva, Soam; Bracewell, Daniel G

2011-01-01

When considering worldwide demand for biopharmaceuticals, it becomes necessary to consider alternative process strategies to improve the economics of manufacturing such molecules. To address this issue, the current study investigates precipitation to selectively isolate the product or remove contaminants and thus assist the initial purification of a intracellular protein. The hypothesis tested was that the combination of two or more precipitating agents will alter the solubility profile of the product through synergistic or antagonistic effects. This principle was investigated through several combinations of ammonium sulfate and sodium citrate at different ratios. A synergistic effect mediated by a known electrostatic interaction of citrate ions with Fab' in addition to the typical salting-out effects was observed. On the basis of the results of the solubility studies, a two step primary recovery route was investigated. In the first step termed conditioning, post-homogenization and before clarification, addition of 0.8 M ammonium sulfate extracted 30% additional product. Clarification performance measured using a scale-down disc stack centrifugation mimic determined a four-fold reduction in centrifuge size requirements. Dual salt precipitation in the second step resulted in >98% recovery of Fab' while removing 36% of the contaminant proteins simultaneously. Copyright © 2011 American Institute of Chemical Engineers (AIChE).

Fringe Formation in Dual-Hologram Interferometry

NASA Technical Reports Server (NTRS)

Burner, A. W.

1989-01-01

A first order geometrical optics treatment of holograms combined with the generation of interference fringes by two point sources is used to describe reference fringe formation in non-diffuse dual-hologram interferometry.

Quantization of liver tissue in dual kVp computed tomography using linear discriminant analysis

NASA Astrophysics Data System (ADS)

Tkaczyk, J. Eric; Langan, David; Wu, Xiaoye; Xu, Daniel; Benson, Thomas; Pack, Jed D.; Schmitz, Andrea; Hara, Amy; Palicek, William; Licato, Paul; Leverentz, Jaynne

2009-02-01

Linear discriminate analysis (LDA) is applied to dual kVp CT and used for tissue characterization. The potential to quantitatively model both malignant and benign, hypo-intense liver lesions is evaluated by analysis of portal-phase, intravenous CT scan data obtained on human patients. Masses with an a priori classification are mapped to a distribution of points in basis material space. The degree of localization of tissue types in the material basis space is related to both quantum noise and real compositional differences. The density maps are analyzed with LDA and studied with system simulations to differentiate these factors. The discriminant analysis is formulated so as to incorporate the known statistical properties of the data. Effective kVp separation and mAs relates to precision of tissue localization. Bias in the material position is related to the degree of X-ray scatter and partial-volume effect. Experimental data and simulations demonstrate that for single energy (HU) imaging or image-based decomposition pixel values of water-like tissues depend on proximity to other iodine-filled bodies. Beam-hardening errors cause a shift in image value on the scale of that difference sought between in cancerous and cystic lessons. In contrast, projection-based decomposition or its equivalent when implemented on a carefully calibrated system can provide accurate data. On such a system, LDA may provide novel quantitative capabilities for tissue characterization in dual energy CT.

Water Chemistry Laboratory Manual.

ERIC Educational Resources Information Center

Jenkins, David; And Others

This manual of laboratory experiments in water chemistry serves a dual function of illustrating fundamental chemical principles of dilute aqueous systems and of providing the student with some familiarity with the chemical measurements commonly used in water and wastewater analysis. Experiments are grouped in categories on the basis of similar…

Increased alertness, better than posture prioritization, explains dual-task performance in prosthesis users and controls under increasing postural and cognitive challenge.

PubMed

Howard, Charla L; Perry, Bonnie; Chow, John W; Wallace, Chris; Stokic, Dobrivoje S

2017-11-01

Sensorimotor impairments after limb amputation impose a threat to stability. Commonly described strategies for maintaining stability are the posture first strategy (prioritization of balance) and posture second strategy (prioritization of concurrent tasks). The existence of these strategies was examined in 13 below-knee prosthesis users and 15 controls during dual-task standing under increasing postural and cognitive challenge by evaluating path length, 95% sway area, and anterior-posterior and medial-lateral amplitudes of the center of pressure. The subjects stood on two force platforms under usual (hard surface/eyes open) and difficult (soft surface/eyes closed) conditions, first alone and while performing a cognitive task without and then with instruction on cognitive prioritization. During standing alone, sway was not significantly different between groups. After adding the cognitive task without prioritization instruction, prosthesis users increased sway more under the dual-task than single-task standing (p ≤ 0.028) during both usual and difficult conditions, favoring the posture second strategy. Controls, however, reduced dual-task sway under a greater postural challenge (p ≤ 0.017), suggesting the posture first strategy. With prioritization of the cognitive task, sway was unchanged or reduced in prosthesis users, suggesting departure from the posture second strategy, whereas controls maintained the posture first strategy. Individual analysis of dual tasking revealed that greater postural demand in controls and greater cognitive challenge in prosthesis users led to both reduced sway and improved cognitive performance, suggesting cognitive-motor facilitation. Thus, activation of additional resources through increased alertness, rather than posture prioritization, may explain dual-task performance in both prosthesis users and controls under increasing postural and cognitive challenge.

Self-Enhancement on a Self-Categorization Leash: Evidence for a Dual-Process Model of First-and Third-Person Perceptions

ERIC Educational Resources Information Center

Zhang, Jinguang

2010-01-01

Research suggests that first- and third-person perceptions are driven by the motive to self-enhance and cognitive processes involving the perception of social norms. This article proposes and tests a dual-process model that predicts an interaction between cognition and motivation. Consistent with the model, Experiment 1 (N = 112) showed that…

A Comparison of Difficulty Levels of Vocabulary in First Grade Basal Readers for Preschool Dual Language Learners and Monolingual English Learners

ERIC Educational Resources Information Center

Leung, Cynthia B.; Silverman, Rebecca; Nandakumar, Ratna; Qian, Xiaoyu; Hines, Sara

2011-01-01

The present study investigated preschoolers' knowledge of vocabulary that appears in first grade basal readers by applying Rasch modeling to data from a researcher-developed receptive picture vocabulary assessment administered to 238 children. Levels of word difficulty for dual language learners (DLLs) and monolingual English learners (MELs) were…

Orbifold E-functions of dual invertible polynomials

NASA Astrophysics Data System (ADS)

Ebeling, Wolfgang; Gusein-Zade, Sabir M.; Takahashi, Atsushi

2016-08-01

An invertible polynomial is a weighted homogeneous polynomial with the number of monomials coinciding with the number of variables and such that the weights of the variables and the quasi-degree are well defined. In the framework of the search for mirror symmetric orbifold Landau-Ginzburg models, P. Berglund and M. Henningson considered a pair (f , G) consisting of an invertible polynomial f and an abelian group G of its symmetries together with a dual pair (f ˜ , G ˜) . We consider the so-called orbifold E-function of such a pair (f , G) which is a generating function for the exponents of the monodromy action on an orbifold version of the mixed Hodge structure on the Milnor fibre of f. We prove that the orbifold E-functions of Berglund-Henningson dual pairs coincide up to a sign depending on the number of variables and a simple change of variables. The proof is based on a relation between monomials (say, elements of a monomial basis of the Milnor algebra of an invertible polynomial) and elements of the whole symmetry group of the dual polynomial.

Efficient material decomposition method for dual-energy X-ray cargo inspection system

NASA Astrophysics Data System (ADS)

Lee, Donghyeon; Lee, Jiseoc; Min, Jonghwan; Lee, Byungcheol; Lee, Byeongno; Oh, Kyungmin; Kim, Jaehyun; Cho, Seungryong

2018-03-01

Dual-energy X-ray inspection systems are widely used today for it provides X-ray attenuation contrast of the imaged object and also its material information. Material decomposition capability allows a higher detection sensitivity of potential targets including purposely loaded impurities in agricultural product inspections and threats in security scans for example. Dual-energy X-ray transmission data can be transformed into two basis material thickness data, and its transformation accuracy heavily relies on a calibration of material decomposition process. The calibration process in general can be laborious and time consuming. Moreover, a conventional calibration method is often challenged by the nonuniform spectral characteristics of the X-ray beam in the entire field-of-view (FOV). In this work, we developed an efficient material decomposition calibration process for a linear accelerator (LINAC) based high-energy X-ray cargo inspection system. We also proposed a multi-spot calibration method to improve the decomposition performance throughout the entire FOV. Experimental validation of the proposed method has been demonstrated by use of a cargo inspection system that supports 6 MV and 9 MV dual-energy imaging.

Dual chamber arrhythmia detection in the implantable cardioverter defibrillator.

PubMed

Dijkman, B; Wellens, H J

2000-10-01

Dual chamber implantable cardioverter defibrillator (ICD) technology extended ICD therapy to more than termination of hemodynamically unstable ventricular tachyarrhythmias. It created the basis for dual chamber arrhythmia management in which dependable detection is important for treatment and prevention of both ventricular and atrial arrhythmias. Dual chamber detection algorithms were investigated in two Medtronic dual chamber ICDs: the 7250 Jewel AF (33 patients) and the 7271 Gem DR (31 patients). Both ICDs use the same PR Logic algorithm to interpret tachycardia as ventricular tachycardia (VT), supraventricular tachycardia (SVT), or dual (VT+ SVT). The accuracy of dual chamber detection was studied in 310 of 1,367 spontaneously occurring tachycardias in which rate criterion only was not sufficient for arrhythmia diagnosis. In 78 episodes there was a double tachycardia, in 223 episodes SVT was detected in the VT or ventricular fibrillation zone, and in 9 episodes arrhythmia was detected outside the boundaries of the PR Logic functioning. In 100% of double tachycardias the VT was correctly diagnosed and received priority treatment. SVT was seen in 59 (19%) episodes diagnosed as VT. The causes of inappropriate detection were (1) algorithm failure (inability to fulfill the PR

Job demands-resources, burnout and intention to leave the nursing profession: a questionnaire survey.

PubMed

Jourdain, Geneviève; Chênevert, Denis

2010-06-01

The aims of the paper are to examine the role of burnout in the relationship between stress factors related to nurses' work and social environment and intention to leave the profession and to investigate the nature of the relationship between burnout and intention to leave the nursing profession. A postulate of the job demands-resources model is that two distinct yet related processes contribute to the development of burnout. The energetic process originates from demands and is mainly centered on emotional exhaustion; the motivational process originates from resources and is mainly centered on depersonalization. Moreover, we postulated that the two components of burnout are linked indirectly to intention to leave the profession via psychosomatic complaints, associated with the energetic process, and via professional commitment, associated with the motivational process. The research model was tested on cross-sectional data collected in 2005 from 1636 registered nurses working in hospitals who responded to a self-administrated questionnaire. Demands are the most important determinants of emotional exhaustion and indirectly induce depersonalization via emotional exhaustion, whereas resources mainly predict depersonalization. Moreover, emotional exhaustion and depersonalization are linked to psychosomatic complaints and professional commitment, which are in turn associated with intention to leave the profession. The results suggest that a dual strategy is needed in order to retain nurses within the profession: a decrease in job demands, coupled with an increase in available job resources. In particular, nurses' tasks and role should be restructured to reduce work overload and increase the meaning of their work. (c) 2009 Elsevier Ltd. All rights reserved.

High effective inverse dynamics modelling for dual-arm robot

NASA Astrophysics Data System (ADS)

Shen, Haoyu; Liu, Yanli; Wu, Hongtao

2018-05-01

To deal with the problem of inverse dynamics modelling for dual arm robot, a recursive inverse dynamics modelling method based on decoupled natural orthogonal complement is presented. In this model, the concepts and methods of Decoupled Natural Orthogonal Complement matrices are used to eliminate the constraint forces in the Newton-Euler kinematic equations, and the screws is used to express the kinematic and dynamics variables. On this basis, the paper has developed a special simulation program with symbol software of Mathematica and conducted a simulation research on the a dual-arm robot. Simulation results show that the proposed method based on decoupled natural orthogonal complement can save an enormous amount of CPU time that was spent in computing compared with the recursive Newton-Euler kinematic equations and the results is correct and reasonable, which can verify the reliability and efficiency of the method.

A dual system model of preferences under risk.

PubMed

Mukherjee, Kanchan

2010-01-01

This article presents a dual system model (DSM) of decision making under risk and uncertainty according to which the value of a gamble is a combination of the values assigned to it independently by the affective and deliberative systems. On the basis of research on dual process theories and empirical research in Hsee and Rottenstreich (2004) and Rottenstreich and Hsee (2001) among others, the DSM incorporates (a) individual differences in disposition to rational versus emotional decision making, (b) the affective nature of outcomes, and (c) different task construals within its framework. The model has good descriptive validity and accounts for (a) violation of nontransparent stochastic dominance, (b) fourfold pattern of risk attitudes, (c) ambiguity aversion, (d) common consequence effect, (e) common ratio effect, (f) isolation effect, and (g) coalescing and event-splitting effects. The DSM is also used to make several novel predictions of conditions under which specific behavior patterns may or may not occur.

Analysis of laser light-scattering interferometric devices for in-line diagnostics of moving particles

NASA Astrophysics Data System (ADS)

Naqwi, Amir A.; Durst, Franz

1993-07-01

Dual-beam laser measuring techniques are now being used, not only for velocimetry, but also for simultaneous measurements of particle size and velocity in particulate two-phase flows. However, certain details of these optical techniques, such as the effect of Gaussian beam profiles on the accuracy of the measurements, need to be further explored. To implement innovative improvements, a general analytic framework is needed in which performances of various dual-beam instruments could be quantitatively studied and compared. For this purpose, the analysis of light scattering in a generalized dual-wave system is presented in this paper. The present simulation model provides a basis for studying effects of nonplanar beam structures of incident waves, taking into account arbitrary modes of polarization. A polarizer is included in the receiving optics as well. The peculiar aspects of numerical integration of scattered light over circular, rectangular, and truncated circular apertures are also considered.

The dual algebraic Riccati equations and the set of all solutions of the discrete-time Riccati equation

NASA Astrophysics Data System (ADS)

Zhang, Liangyin; Chen, Michael Z. Q.; Li, Chanying

2017-07-01

In this paper, two new pairs of dual continuous-time algebraic Riccati equations (CAREs) and dual discrete-time algebraic Riccati equations (DAREs) are proposed. The dual DAREs are first studied with some nonsingularity assumptions on the system matrix and the parameter matrix. Then, in the case of singular matrices, a generalised inverse is introduced to deal with the dual DARE problem. These dual AREs can easily lead us to an iterative procedure for finding the anti-stabilising solutions, especially to DARE, by means of that for the stabilising solutions. Furthermore, we provide the counterpart results on the set of all solutions to DARE inspired by the results for CARE. Two examples are presented to illustrate the theoretical results.

Continuous 1052, 1064 nm dual-wavelength Nd:YAG laser

NASA Astrophysics Data System (ADS)

Wang, Xiaozhong; Yuan, Haiyang; Wang, Mingshan; Huang, Wencai

2016-10-01

Dual-wavelength lasers are usually obtained through balancing the net gain of the two oscillating lines. Competition between transitions 1052 nm, 1061 nm and 1064 nm is utilized to realize a continuous wave 1052 and 1064 nm dual-wavelength Nd:YAG laser firstly in this paper. A specially designed Fabry-Perot band-pass filter is exploited as output coupler to control the thresholds of the oscillating wavelengths. The maximum power of the dual-wavelength laser is 1.6 W and the slope efficiency is about 10%. The power instability of the output dual-wavelength laser is smaller than ±4% in half an hour. The mechanism presented in this paper may provide a new way to obtain dual-wavelength lasers.

Coding for reliable satellite communications

NASA Technical Reports Server (NTRS)

Lin, S.

1984-01-01

Several error control coding techniques for reliable satellite communications were investigated to find algorithms for fast decoding of Reed-Solomon codes in terms of dual basis. The decoding of the (255,223) Reed-Solomon code, which is used as the outer code in the concatenated TDRSS decoder, was of particular concern.

(Im)Politeness in Cross-Cultural Encounters

ERIC Educational Resources Information Center

House, Juliane

2012-01-01

In this article I will first discuss the notions of "politeness" and "impoliteness" including a multilevel model of politeness and impoliteness that relates universal levels to culture- and language-specific ones. Given this framework and my earlier postulation of a set of parameters along which members of two linguacultures differ in terms of…

A hierarchical preconditioner for the electric field integral equation on unstructured meshes based on primal and dual Haar bases

NASA Astrophysics Data System (ADS)

Adrian, S. B.; Andriulli, F. P.; Eibert, T. F.

2017-02-01

A new hierarchical basis preconditioner for the electric field integral equation (EFIE) operator is introduced. In contrast to existing hierarchical basis preconditioners, it works on arbitrary meshes and preconditions both the vector and the scalar potential within the EFIE operator. This is obtained by taking into account that the vector and the scalar potential discretized with loop-star basis functions are related to the hypersingular and the single layer operator (i.e., the well known integral operators from acoustics). For the single layer operator discretized with piecewise constant functions, a hierarchical preconditioner can easily be constructed. Thus the strategy we propose in this work for preconditioning the EFIE is the transformation of the scalar and the vector potential into operators equivalent to the single layer operator and to its inverse. More specifically, when the scalar potential is discretized with star functions as source and testing functions, the resulting matrix is a single layer operator discretized with piecewise constant functions and multiplied left and right with two additional graph Laplacian matrices. By inverting these graph Laplacian matrices, the discretized single layer operator is obtained, which can be preconditioned with the hierarchical basis. Dually, when the vector potential is discretized with loop functions, the resulting matrix can be interpreted as a hypersingular operator discretized with piecewise linear functions. By leveraging on a scalar Calderón identity, we can interpret this operator as spectrally equivalent to the inverse single layer operator. Then we use a linear-in-complexity, closed-form inverse of the dual hierarchical basis to precondition the hypersingular operator. The numerical results show the effectiveness of the proposed preconditioner and the practical impact of theoretical developments in real case scenarios.

Dual-Pump Coherent Anti-Stokes Raman Scattering Temperature and CO2 Concentration Measurements

NASA Technical Reports Server (NTRS)

Lucht, Robert P.; Velur-Natarajan, Viswanathan; Carter, Campbell D.; Grinstead, Keith D., Jr.; Gord, James R.; Danehy, Paul M.; Fiechtner, G. J.; Farrow, Roger L.

2003-01-01

Measurements of temperature and CO2 concentration using dual-pump coherent anti-Stokes Raman scattering, (CARS) are described. The measurements were performed in laboratory flames,in a room-temperature gas cell, and on an engine test stand at the U.S. Air Force Research Laboratory, Wright-Patterson Air Force Base. A modeless dye laser, a single-mode Nd:YAG laser, and an unintensified back-illuminated charge-coupled device digital camera were used for these measurements. The CARS measurements were performed on a single-laser-shot basis. The standard deviations of the temperatures and CO2 mole fractions determined from single-shot dual-pump CARS spectra in steady laminar propane/air flames were approximately 2 and 10% of the mean values of approximately 2000 K and 0.10, respectively. The precision and accuracy of single-shot temperature measurements obtained from the nitrogen part of the dual-pump CARS system were investigated in detail in near-adiabatic hydrogen/air/CO2 flames. The precision of the CARS temperature measurements was found to be comparable to the best results reported in the literature for conventional two-laser, single-pump CARS. The application of dual-pump CARS for single-shot measurements in a swirl-stabilized combustor fueled with JP-8 was also demonstrated.

A fast dual wavelength laser beam fluid-less optical CT scanner for radiotherapy 3D gel dosimetry I: design and development

NASA Astrophysics Data System (ADS)

Ramm, Daniel

2018-02-01

Three dimensional dosimetry by optical CT readout of radiosensitive gels or solids has previously been indicated as a solution for measurement of radiotherapy 3D dose distributions. The clinical uptake of these dosimetry methods has been limited, partly due to impracticalities of the optical readout such as the expertise and labour required for refractive index fluid matching. In this work a fast laser beam optical CT scanner is described, featuring fluid-less and dual wavelength operation. A second laser with a different wavelength is used to provide an alternative reference scan to the commonly used pre-irradiation scan. Transmission data for both wavelengths is effectively acquired simultaneously, giving a single scan process. Together with the elimination of refractive index fluid matching issues, scanning practicality is substantially improved. Image quality and quantitative accuracy were assessed for both dual and single wavelength methods. The dual wavelength scan technique gave improvements in uniformity of reconstructed optical attenuation coefficients in the sample 3D volume. This was due to a reduction of artefacts caused by scan to scan changes. Optical attenuation measurement accuracy was similar for both dual and single wavelength modes of operation. These results established the basis for further work on dosimetric performance.

Revisiting the theoretical basis of the endosymbiotic origin of plastids in the original context of Lynn Margulis on the origin of mitosing, eukaryotic cells.

PubMed

Sato, Naoki

2017-12-07

Fifty years ago, Lynn Margulis proposed a comprehensive hypothesis on the origin of eukaryotic cells with an emphasis on the origin of mitosis. This hypothesis postulated that the eukaryotic cell is a composite of different parts as a result of the symbiosis of various different bacteria. In this hypothesis, she integrated previously proposed ideas that mitochondria and chloroplasts were descendants of endosymbionts that originated from aerobic bacteria and blue-green algae (now cyanobacteria), respectively. However, the major part of her hypothesis, which she believed to be original, was the origin of mitosis. The core of her postulate involved a chromosome partition mechanism dependent on DNA-microtubule binding, which originated from a hypothetical centriole-DNA complex, with an ability to replicate. Surprisingly, her complete lack of real experimental works in the cytoskeleton, cell motility, or paleontology did not prevent this 29-year-old junior scientist from assembling archival knowledge and constructing a narrative on the evolution of all organisms. Whether the centriole-DNA complex originated from a spirochete or not was a minor anecdote in this initial postulate. Unfortunately, this hypothesis on the origin of mitosis, which she believed to be a holistic unity, testable by experiments, was entirely refuted. Despite falsification of her original narrative as a whole, her success as a founder of endosymbiotic theory on the origin of mitochondria and chloroplasts is undoubted. We will discuss the reasons for her success in terms of the historical situation in the latter half of the 20th century. Copyright © 2017 Elsevier Ltd. All rights reserved.

Approaches to emergent spacetime in gauge/gravity duality

NASA Astrophysics Data System (ADS)

Sully, James Kenneth

2013-08-01

In this thesis we explore approaches to emergent local spacetime in gauge/gravity duality. We first conjecture that every CFT with a large-N type limit and a parametrically large gap in the spectrum of single-trace operators has a local bulk dual. We defend this conjecture by counting consistent solutions to the four-point function in simple scalar models and matching to the number of local interaction terms in the bulk. Next, we proceed to explicitly construct local bulk operators using smearing functions. We argue that this construction allows one to probe inside black hole horizons for only short times. We then suggest that the failure to construct bulk operators inside a black hole at late times is indicative of a break-down of local effective field theory at the black hole horizon. We argue that the postulates of black hole complementarity are inconsistent and cannot be realized within gauge/gravity duality. We argue that the most conservative solution is a firewall at the black hole horizon and we critically explore alternative resolutions. We then examine the CGHS model of two-dimensional gravity to look for dynamical formation of firewalls. We find that the CGHS model does not exhibit firewalls, but rather contains long-lived remnants. We argue that, while this is consistent for the CGHS model, it cannot be so in higher-dimensional theories of gravity. Lastly, we turn to F-theory, and detail local and global obstructions to writing elliptic fibrations in Tate form. We determine more general possible forms.

A novel cell-based assay for inhibitory anti-muscarinic type 3 receptor antibodies in primary Sjögren's syndrome.

PubMed

Bastian, Isabell; Gordon, Tom P; Jackson, Michael W

2015-12-01

Inhibitory autoantibodies acting at the muscarinic acetylcholine receptor type 3 (M3R) are postulated to mediate autonomic dysfunction, including decreased salivary and lacrimal gland output and extra-glandular manifestations, in patients with primary Sjögren's syndrome. However, the contention that anti-M3R antibodies are pathogenic in patients remains untested, due to a lack of assays both sophisticated enough to detect inhibitory anti-M3R antibodies yet suitable for screening large patient cohorts. In the current study, we have established a cell-based bioassay of M3R activity, based on dual transfection of the M3R and a luciferase reporter gene. The bioassay is capable of capturing real-time agonist-mediated signalling of the M3R, which is inhibited specifically by patient IgG that have previously been demonstrated to have anti-M3R activity. The assay can be run in multi-well culture plates, and analysed using simple luminescence readers. As such, the new bioassay incorporating M3R-mediated luciferase transduction is the first assay adaptable to common diagnostic platforms that is capable of determining the presence in patient serum of functionally active anti-M3R autoantibodies. The new bioassay should prove useful for large cohort screening studies aiming to correlate the presence in patients of inhibitory anti-M3R antibodies with symptoms of both glandular and extra-glandular autonomic dysfunction. Copyright © 2015 Elsevier B.V. All rights reserved.

Non Abelian T-duality in Gauged Linear Sigma Models

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

Bizet, Nana Cabo; Martínez-Merino, Aldo; Zayas, Leopoldo A. Pando

Abelian T-duality in Gauged Linear Sigma Models (GLSM) forms the basis of the physical understanding of Mirror Symmetry as presented by Hori and Vafa. We consider an alternative formulation of Abelian T-duality on GLSM’s as a gauging of a global U(1) symmetry with the addition of appropriate Lagrange multipliers. For GLSMs with Abelian gauge groups and without superpotential we reproduce the dual models introduced by Hori and Vafa. We extend the construction to formulate non-Abelian T-duality on GLSMs with global non-Abelian symmetries. The equations of motion that lead to the dual model are obtained for a general group, they dependmore » in general on semi-chiral superfields; for cases such as SU(2) they depend on twisted chiral superfields. We solve the equations of motion for an SU(2) gauged group with a choice of a particular Lie algebra direction of the vector superfield. This direction covers a non-Abelian sector that can be described by a family of Abelian dualities. The dual model Lagrangian depends on twisted chiral superfields and a twisted superpotential is generated. We explore some non-perturbative aspects by making an Ansatz for the instanton corrections in the dual theories. We verify that the effective potential for the U(1) field strength in a fixed configuration on the original theory matches the one of the dual theory. Imposing restrictions on the vector superfield, more general non-Abelian dual models are obtained. We analyze the dual models via the geometry of their susy vacua.« less

Non Abelian T-duality in Gauged Linear Sigma Models

DOE PAGES

Bizet, Nana Cabo; Martínez-Merino, Aldo; Zayas, Leopoldo A. Pando; ...

2018-04-01

Abelian T-duality in Gauged Linear Sigma Models (GLSM) forms the basis of the physical understanding of Mirror Symmetry as presented by Hori and Vafa. We consider an alternative formulation of Abelian T-duality on GLSM’s as a gauging of a global U(1) symmetry with the addition of appropriate Lagrange multipliers. For GLSMs with Abelian gauge groups and without superpotential we reproduce the dual models introduced by Hori and Vafa. We extend the construction to formulate non-Abelian T-duality on GLSMs with global non-Abelian symmetries. The equations of motion that lead to the dual model are obtained for a general group, they dependmore » in general on semi-chiral superfields; for cases such as SU(2) they depend on twisted chiral superfields. We solve the equations of motion for an SU(2) gauged group with a choice of a particular Lie algebra direction of the vector superfield. This direction covers a non-Abelian sector that can be described by a family of Abelian dualities. The dual model Lagrangian depends on twisted chiral superfields and a twisted superpotential is generated. We explore some non-perturbative aspects by making an Ansatz for the instanton corrections in the dual theories. We verify that the effective potential for the U(1) field strength in a fixed configuration on the original theory matches the one of the dual theory. Imposing restrictions on the vector superfield, more general non-Abelian dual models are obtained. We analyze the dual models via the geometry of their susy vacua.« less

The Man of Dual Nationality.

ERIC Educational Resources Information Center

Abe, Yoshio

1985-01-01

Presents an English translation of the first few pages, set in a Japanese internment camp in the U.S. during World War II, of a Japanese novel about the problems of dual nationality and personal identity. (KH)

A machine learning approach for efficient uncertainty quantification using multiscale methods

NASA Astrophysics Data System (ADS)

Chan, Shing; Elsheikh, Ahmed H.

2018-02-01

Several multiscale methods account for sub-grid scale features using coarse scale basis functions. For example, in the Multiscale Finite Volume method the coarse scale basis functions are obtained by solving a set of local problems over dual-grid cells. We introduce a data-driven approach for the estimation of these coarse scale basis functions. Specifically, we employ a neural network predictor fitted using a set of solution samples from which it learns to generate subsequent basis functions at a lower computational cost than solving the local problems. The computational advantage of this approach is realized for uncertainty quantification tasks where a large number of realizations has to be evaluated. We attribute the ability to learn these basis functions to the modularity of the local problems and the redundancy of the permeability patches between samples. The proposed method is evaluated on elliptic problems yielding very promising results.

On the theoretical link between LLL-reduction and Lambda-decorrelation

NASA Astrophysics Data System (ADS)

Lannes, A.

2013-04-01

The LLL algorithm, introduced by Lenstra et al. (Math Ann 261:515-534, 1982), plays a key role in many fields of applied mathematics. In particular, it is used as an effective numerical tool for preconditioning the integer least-squares problems arising in high-precision geodetic positioning and Global Navigation Satellite Systems (GNSS). In 1992, Teunissen developed a method for solving these nearest-lattice point (NLP) problems. This method is referred to as Lambda (for Least-squares AMBiguity Decorrelation Adjustment). The preconditioning stage of Lambda corresponds to its decorrelation algorithm. From an epistemological point of view, the latter was devised through an innovative statistical approach completely independent of the LLL algorithm. Recent papers pointed out some similarities between the LLL algorithm and the Lambda-decorrelation algorithm. We try to clarify this point in the paper. We first introduce a parameter measuring the orthogonality defect of the integer basis in which the NLP problem is solved, the LLL-reduced basis of the LLL algorithm, or the Λ -basis of the Lambda method. With regard to this problem, the potential qualities of these bases can then be compared. The Λ -basis is built by working at the level of the variance-covariance matrix of the float solution, while the LLL-reduced basis is built by working at the level of its inverse. As a general rule, the orthogonality defect of the Λ -basis is greater than that of the corresponding LLL-reduced basis; these bases are however very close to one another. To specify this tight relationship, we present a method that provides the dual LLL-reduced basis of a given Λ -basis. As a consequence of this basic link, all the recent developments made on the LLL algorithm can be applied to the Lambda-decorrelation algorithm. This point is illustrated in a concrete manner: we present a parallel Λ -type decorrelation algorithm derived from the parallel LLL algorithm of Luo and Qiao (Proceedings of the fourth international C^* conference on computer science and software engineering. ACM Int Conf P Series. ACM Press, pp 93-101, 2012).

Fission Product Yield Study of 235U, 238U and 239Pu Using Dual-Fission Ionization Chambers

NASA Astrophysics Data System (ADS)

Bhatia, C.; Fallin, B.; Howell, C.; Tornow, W.; Gooden, M.; Kelley, J.; Arnold, C.; Bond, E.; Bredeweg, T.; Fowler, M.; Moody, W.; Rundberg, R.; Rusev, G.; Vieira, D.; Wilhelmy, J.; Becker, J.; Macri, R.; Ryan, C.; Sheets, S.; Stoyer, M.; Tonchev, A.

2014-05-01

To resolve long-standing differences between LANL and LLNL regarding the correct fission basis for analysis of nuclear test data [M.B. Chadwick et al., Nucl. Data Sheets 111, 2891 (2010); H. Selby et al., Nucl. Data Sheets 111, 2891 (2010)], a collaboration between TUNL/LANL/LLNL has been established to perform high-precision measurements of neutron induced fission product yields. The main goal is to make a definitive statement about the energy dependence of the fission yields to an accuracy better than 2-3% between 1 and 15 MeV, where experimental data are very scarce. At TUNL, we have completed the design, fabrication and testing of three dual-fission chambers dedicated to 235U, 238U, and 239Pu. The dual-fission chambers were used to make measurements of the fission product activity relative to the total fission rate, as well as for high-precision absolute fission yield measurements. The activation method was employed, utilizing the mono-energetic neutron beams available at TUNL. Neutrons of 4.6, 9.0, and 14.5 MeV were produced via the 2H(d,n)3He reaction, and for neutrons at 14.8 MeV, the 3H(d,n)4He reaction was used. After activation, the induced γ-ray activity of the fission products was measured for two months using high-resolution HPGe detectors in a low-background environment. Results for the yield of seven fission fragments of 235U, 238U, and 239Pu and a comparison to available data at other energies are reported. For the first time results are available for neutron energies between 2 and 14 MeV.

Measuring the Diversity Awareness of Social Work Students: The Dual Perspective Inventory

ERIC Educational Resources Information Center

Anderson, Wandarah; Hayashi, Reiko; Frost, Caren J.

2009-01-01

The Dual Perspective Inventory was implemented to measure the diversity awareness of first-year MSW students at a university in the western U.S. Data were collected at the beginning of the first semester from students who enrolled in a course on diversity, and again at the end of the semester when the students were about to complete the course.…

The Combine Project: An Experience in a Dual-Language Classroom = El proyecto de la cosechadora: una experiencia en una clase bilingue.

ERIC Educational Resources Information Center

Wilson, Rebecca

This article, also available in Spanish, describes what happened when a bilingual kindergarten class in West Liberty, Iowa, investigated a combine. The dual-language Kindergarten program supports content area instruction in both Spanish and English. The first part of the article tells the story of the Combine Project, this class's first project…

A random spatial network model based on elementary postulates

USGS Publications Warehouse

Karlinger, Michael R.; Troutman, Brent M.

1989-01-01

A model for generating random spatial networks that is based on elementary postulates comparable to those of the random topology model is proposed. In contrast to the random topology model, this model ascribes a unique spatial specification to generated drainage networks, a distinguishing property of some network growth models. The simplicity of the postulates creates an opportunity for potential analytic investigations of the probabilistic structure of the drainage networks, while the spatial specification enables analyses of spatially dependent network properties. In the random topology model all drainage networks, conditioned on magnitude (number of first-order streams), are equally likely, whereas in this model all spanning trees of a grid, conditioned on area and drainage density, are equally likely. As a result, link lengths in the generated networks are not independent, as usually assumed in the random topology model. For a preliminary model evaluation, scale-dependent network characteristics, such as geometric diameter and link length properties, and topologic characteristics, such as bifurcation ratio, are computed for sets of drainage networks generated on square and rectangular grids. Statistics of the bifurcation and length ratios fall within the range of values reported for natural drainage networks, but geometric diameters tend to be relatively longer than those for natural networks.

Structural Basis of Multifunctionality in a Vitamin B[subscript 12]-processing Enzyme

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

Koutmos, Markos; Gherasim, Carmen; Smith, Janet L.

An early step in the intracellular processing of vitamin B{sub 12} involves CblC, which exhibits dual reactivity, catalyzing the reductive decyanation of cyanocobalamin (vitamin B{sub 12}), and the dealkylation of alkylcobalamins (e.g. methylcobalamin; MeCbl). Insights into how the CblC scaffold supports this chemical dichotomy have been unavailable despite it being the most common locus of patient mutations associated with inherited cobalamin disorders that manifest in both severe homocystinuria and methylmalonic aciduria. Herein, we report structures of human CblC, with and without bound MeCbl, which provide novel biochemical insights into its mechanism of action. Our results reveal that CblC is themore » most divergent member of the NADPH-dependent flavin reductase family and can use FMN or FAD as a prosthetic group to catalyze reductive decyanation. Furthermore, CblC is the first example of an enzyme with glutathione transferase activity that has a sequence and structure unrelated to the GST superfamily. CblC thus represents an example of evolutionary adaptation of a common structural platform to perform diverse chemistries. The CblC structure allows us to rationalize the biochemical basis of a number of pathological mutations associated with severe clinical phenotypes.« less

Method for continuously recovering metals using a dual zone chemical reactor

DOEpatents

Bronson, M.C.

1995-02-14

A dual zone chemical reactor continuously processes metal-containing materials while regenerating and circulating a liquid carrier. The starting materials are fed into a first reaction zone of a vessel containing a molten salt carrier. The starting materials react to form a metal product and a by-product that dissolves in the molten salt that flows to a second reaction zone in the reaction vessel. The second reaction zone is partitioned from, but in fluid communication with, the first reaction zone. The liquid carrier continuously circulates along a pathway between the first reaction zone and the second reaction zone. A reactive gas is introduced into the second reaction zone to react with the reaction by-product to generate the molten salt. The metal product, the gaseous waste products, and the excess liquid carrier are removed without interrupting the operation of the reactor. The design of the dual zone reactor can be adapted to combine a plurality of liquid carrier regeneration zones in a multiple dual zone chemical reactor for production scale processing. 6 figs.

Impact of a Dual PharmD/MBA Degree on Graduates' Academic Performance, Career Opportunities, and Earning Potential

PubMed Central

Chumney, Elinor C.G.; Jones, Kathy J.

2008-01-01

Objective To evaluate the academic experience and satisfaction of students who completed a dual PharmD/MBA degree program and the program's long-term impact on the students' career choice and earning potential. Methods GPAs, job placement, and starting job salaries were compared between graduates who completed the dual PharmD/MBA program and those who completed only the PharmD program. A satisfaction survey instrument was administered to 17 students who completed the dual PharmD/MBA degree program in May 2007. Data from a standardized job placement and starting salary survey instrument completed by all PharmD graduates were also obtained, as well as all students' final grade point averages (GPAs). GPAs, job placement, and starting job salaries were compared between graduates who had completed the dual PharmD/MBA program and those who had completed only the PharmD program. Results The graduating GPAs of dual-degree students were higher than those of both pharmacy (3.52 vs 3.41, p > 0.10) and business (3.82 vs. 3.68, p = 0.018) students not enrolled in the dual-degree program. Dual-degree students were slightly less likely to enter a residency (17% vs. 27%, p = 0.44) than other pharmacy graduates. Among those who elected not to pursue a residency, both mean starting salaries ($111,090 vs. $101,965) and mean total first-year compensation ($127,290 vs. $110,388) were significantly higher for dual-degree graduates compared to the PharmD graduates. Conclusions Students enrolled in the dual-degree program did slightly better academically than students who completed only the MBA or PharmD programs and indicated a high level of satisfaction with the program. Dual-degree graduates reported increased career opportunities and were slated to earn significantly more during their first year in the workforce. These results affirm continuation of our program and make the case for support of similar programs across the nation. PMID:18483594

Phase 2 Study of AZD2014, a Dual mTORC1/mTORC1 Inhibitor,for NF2 Patients with Progressive or Symptomatic Meningiomas

DTIC Science & Technology

2017-06-01

will be administered on a repeating basis at a dose of 125 mg twice daily for two consecutive days out of every seven days (1 cycle = 28 days ...a repeating basis at a dose of 125 mg twice daily for two consecutive days out of every seven days (1 cycle = 28 days ). Treatment will continue until...immunohistochemical analysis of blood and tumor specimens. Funding support N/A Name Justin Jordan, MD, MPH Project Role Co-Investigator Nearest

The Wellbeing of Army Personnel in Dual-Military Marriages

DTIC Science & Technology

2013-06-01

experience both negative health and lower subjective feelings of wellbeing . The first year of this study has been focused on research lab development...findings to report. 15. SUBJECT TERMS Dual-Military Marriages, Wellbeing , Health , Work-family Conflict 16. SECURITY CLASSIFICATION OF: 17...However there have been very few studies that have examined the health and wellbeing of individuals in dual-military marital relationships. The

A Quantitative Assessment of Texas House Bill 505: College Dual Credit Courses and Academic Success among High School Students

ERIC Educational Resources Information Center

Klimitchek, Michelle Leigh

2017-01-01

Texas House Bill 505 expanded dual credit programs to include high school freshmen and sophomores. This study examined the relationship of high school student characteristics and academic success in first attempt dual credit courses. Characteristics refer to year in high school, gender, and high school size. Success is passing scores in English,…

The ocular pathology of Norrie disease in a fetus of 11 weeks' gestational age.

PubMed

Parsons, M A; Curtis, D; Blank, C E; Hughes, H N; McCartney, A C

1992-01-01

The ocular pathology of Norrie disease was studied for the first time in a fetus of 11 weeks' gestation, following prenatal diagnosis using genetic markers for Norrie disease and elective abortion. The eyes were histologically normal, with no evidence of primary neuroectodermal maldevelopment of the retina, previously postulated to be the cause of the ocular changes. We believe that the retinal and other manifestations of Norrie disease are the result of a primary abnormality of vascular proliferation, probably in relation to persistent hyperplastic primary vitreous after approximately 14 weeks' gestation. We postulate that the ocular and otological effects of Norrie disease may be due to a genetically mediated abnormality of secretion of, or sensitivity to, angiogenic growth factors at endodermal-neuroectodermal interfaces during fetal and postnatal development.

Dynamic phase coexistence in glass-forming liquids.

PubMed

Pastore, Raffaele; Coniglio, Antonio; Ciamarra, Massimo Pica

2015-07-09

One of the most controversial hypotheses for explaining the heterogeneous dynamics of glasses postulates the temporary coexistence of two phases characterized by a high and by a low diffusivity. In this scenario, two phases with different diffusivities coexist for a time of the order of the relaxation time and mix afterwards. Unfortunately, it is difficult to measure the single-particle diffusivities to test this hypothesis. Indeed, although the non-Gaussian shape of the van-Hove distribution suggests the transient existence of a diffusivity distribution, it is not possible to infer from this quantity whether two or more dynamical phases coexist. Here we provide the first direct observation of the dynamical coexistence of two phases with different diffusivities, by showing that in the deeply supercooled regime the distribution of the single-particle diffusivities acquires a transient bimodal shape. We relate this distribution to the heterogeneity of the dynamics and to the breakdown of the Stokes-Einstein relation, and we show that the coexistence of two dynamical phases occurs up to a timescale growing faster than the relaxation time on cooling, for some of the considered models. Our work offers a basis for rationalizing the dynamics of supercooled liquids and for relating their structural and dynamical properties.

Fuzzy Logic for Incidence Geometry

PubMed Central

2016-01-01

The paper presents a mathematical framework for approximate geometric reasoning with extended objects in the context of Geography, in which all entities and their relationships are described by human language. These entities could be labelled by commonly used names of landmarks, water areas, and so forth. Unlike single points that are given in Cartesian coordinates, these geographic entities are extended in space and often loosely defined, but people easily perform spatial reasoning with extended geographic objects “as if they were points.” Unfortunately, up to date, geographic information systems (GIS) miss the capability of geometric reasoning with extended objects. The aim of the paper is to present a mathematical apparatus for approximate geometric reasoning with extended objects that is usable in GIS. In the paper we discuss the fuzzy logic (Aliev and Tserkovny, 2011) as a reasoning system for geometry of extended objects, as well as a basis for fuzzification of the axioms of incidence geometry. The same fuzzy logic was used for fuzzification of Euclid's first postulate. Fuzzy equivalence relation “extended lines sameness” is introduced. For its approximation we also utilize a fuzzy conditional inference, which is based on proposed fuzzy “degree of indiscernibility” and “discernibility measure” of extended points. PMID:27689133

Traditional Chinese medicine valuably augments therapeutic options in the treatment of climacteric syndrome.

PubMed

Eisenhardt, Sarah; Fleckenstein, Johannes

2016-07-01

Climacteric syndrome refers to recurring symptoms such as hot flashes, chills, headache, irritability and depression. This is usually experienced by menopausal women and can be related to a hormonal reorganization in the hypothalamic-pituitary-gonadal axis. In Traditional Chinese Medicine, originating 1000s of years ago, above-mentioned symptoms can be interpreted on the basis of the philosophic diagnostic concepts, such as the imbalance of Yin and Yang, the Zang-Fu and Basic substances (e.g. Qi, Blood and Essence). These concepts postulate balance and harmonization as the principle aim of a treatment. In this context, it is not astounding that one of the most prominent ancient textbooks dating back to 500-200 BC, Huang di Neijing: The Yellow Emperor's Classic of Internal Medicine gives already first instructions for diagnosis and therapy of climacteric symptoms. For therapy, traditional Chinese medicine comprises five treatment principles: Chinese herbal medicine, TuiNa (a Chinese form of manual therapy), nutrition, activity (e.g. QiGong) and acupuncture (being the most widespread form of treatment used in Europe). This review provides an easy access to the concepts of traditional Chinese medicine particularly regarding to climacteric syndrome and also focuses on current scientific evidence.

Structural and Functional Elucidation of Peptide Ts11 Shows Evidence of a Novel Subfamily of Scorpion Venom Toxins

PubMed Central

Cremonez, Caroline M.; Maiti, Mohitosh; Peigneur, Steve; Cassoli, Juliana Silva; Dutra, Alexandre A. A.; Waelkens, Etienne; Lescrinier, Eveline; Herdewijn, Piet; de Lima, Maria Elena; Pimenta, Adriano M. C.; Arantes, Eliane C.; Tytgat, Jan

2016-01-01

To date, several families of peptide toxins specifically interacting with ion channels in scorpion venom have been described. One of these families comprise peptide toxins (called KTxs), known to modulate potassium channels. Thus far, 202 KTxs have been reported, belonging to several subfamilies of KTxs (called α, β, γ, κ, δ, and λ-KTxs). Here we report on a previously described orphan toxin from Tityus serrulatus venom, named Ts11. We carried out an in-depth structure-function analysis combining 3D structure elucidation of Ts11 and electrophysiological characterization of the toxin. The Ts11 structure is highlighted by an Inhibitor Cystine Knot (ICK) type scaffold, completely devoid of the classical secondary structure elements (α-helix and/or β-strand). This has, to the best of our knowledge, never been described before for scorpion toxins and therefore represents a novel, 6th type of structural fold for these scorpion peptides. On the basis of their preferred interaction with voltage-gated K channels, as compared to all the other targets tested, it can be postulated that Ts11 is the first member of a new subfamily, designated as ε-KTx. PMID:27706049

Structural and Functional Elucidation of Peptide Ts11 Shows Evidence of a Novel Subfamily of Scorpion Venom Toxins.

PubMed

Cremonez, Caroline M; Maiti, Mohitosh; Peigneur, Steve; Cassoli, Juliana Silva; Dutra, Alexandre A A; Waelkens, Etienne; Lescrinier, Eveline; Herdewijn, Piet; de Lima, Maria Elena; Pimenta, Adriano M C; Arantes, Eliane C; Tytgat, Jan

2016-09-30

To date, several families of peptide toxins specifically interacting with ion channels in scorpion venom have been described. One of these families comprise peptide toxins (called KTxs), known to modulate potassium channels. Thus far, 202 KTxs have been reported, belonging to several subfamilies of KTxs (called α, β, γ, κ, δ, and λ-KTxs). Here we report on a previously described orphan toxin from Tityus serrulatus venom, named Ts11. We carried out an in-depth structure-function analysis combining 3D structure elucidation of Ts11 and electrophysiological characterization of the toxin. The Ts11 structure is highlighted by an Inhibitor Cystine Knot (ICK) type scaffold, completely devoid of the classical secondary structure elements (α-helix and/or β-strand). This has, to the best of our knowledge, never been described before for scorpion toxins and therefore represents a novel, 6th type of structural fold for these scorpion peptides. On the basis of their preferred interaction with voltage-gated K channels, as compared to all the other targets tested, it can be postulated that Ts11 is the first member of a new subfamily, designated as ε-KTx.

High-power dual-wavelength Ho-doped fiber laser at >2 μm tandem pumped by a 1.15 μm fiber laser

PubMed Central

Jin, Xiaoxi; Lou, Zhaokai; Chen, Yizhu; Zhou, Pu; Zhang, Hanwei; Xiao, Hu; Liu, Zejin

2017-01-01

We demonstrated a high-power continuous-wave (CW) dual-wavelength Ho-doped fiber laser (HDFL) at 2049 nm and 2153 nm with a simple coupled-cavity configuration. A ~100 W laser diode-pumped fiber laser at 1150 nm served as the pump source. The maximum output power reached ~22.3 W and the slope efficiency was 23%. By altering the incident pump power, the power ratio of two signal wavelengths could be tuned in a large range due to gain competition. As far as we know, this is the first CW dual-wavelength HDFL with the power exceeding ten-watt-level, and the first dual-wavelength HDFL with the central wavelengths exceeding 2.0 μm and 2.15 μm respectively. PMID:28181571

High-power dual-wavelength Ho-doped fiber laser at >2 μm tandem pumped by a 1.15 μm fiber laser

NASA Astrophysics Data System (ADS)

Jin, Xiaoxi; Lou, Zhaokai; Chen, Yizhu; Zhou, Pu; Zhang, Hanwei; Xiao, Hu; Liu, Zejin

2017-02-01

We demonstrated a high-power continuous-wave (CW) dual-wavelength Ho-doped fiber laser (HDFL) at 2049 nm and 2153 nm with a simple coupled-cavity configuration. A ~100 W laser diode-pumped fiber laser at 1150 nm served as the pump source. The maximum output power reached ~22.3 W and the slope efficiency was 23%. By altering the incident pump power, the power ratio of two signal wavelengths could be tuned in a large range due to gain competition. As far as we know, this is the first CW dual-wavelength HDFL with the power exceeding ten-watt-level, and the first dual-wavelength HDFL with the central wavelengths exceeding 2.0 μm and 2.15 μm respectively.

Sweepoviruses Cause Disease in Sweet Potato and Related Ipomoea spp.: Fulfilling Koch's Postulates for a Divergent Group in the Genus Begomovirus

PubMed Central

Márquez-Martín, Belén; Moriones, Enrique; Navas-Castillo, Jesús

2011-01-01

Sweet potato (Ipomoea batatas) and related Ipomoea species are frequently infected by monopartite begomoviruses (genus Begomovirus, family Geminiviridae), known as sweepoviruses. Unlike other geminiviruses, the genomes of sweepoviruses have been recalcitrant to rendering infectious clones to date. Thus, Koch's postulates have not been fullfilled for any of the viruses in this group. Three novel species of sweepoviruses have recently been described in Spain: Sweet potato leaf curl Lanzarote virus (SPLCLaV), Sweet potato leaf curl Spain virus (SPLCSV) and Sweet potato leaf curl Canary virus (SPLCCaV). Here we describe the generation of the first infectious clone of an isolate (ES:MAL:BG30:06) of SPLCLaV. The clone consisted of a complete tandem dimeric viral genome in a binary vector. Successful infection by agroinoculation of several species of Ipomoea (including sweet potato) and Nicotiana benthamiana was confirmed by PCR, dot blot and Southern blot hybridization. Symptoms observed in infected plants consisted of leaf curl, yellowing, growth reduction and vein yellowing. Two varieties of sweet potato, ‘Beauregard’ and ‘Promesa’, were infected by agroinoculation, and symptoms of leaf curl and interveinal loss of purple colouration were observed, respectively. The virus present in agroinfected plants was readily transmitted by the whitefly Bemisia tabaci to I. setosa plants. The progeny virus population present in agroinfected I. setosa and sweet potato plants was isolated and identity to the original isolate was confirmed by sequencing. Therefore, Koch's postulates were fulfilled for the first time for a sweepovirus. PMID:22073314

Sweepoviruses cause disease in sweet potato and related Ipomoea spp.: fulfilling Koch's postulates for a divergent group in the genus begomovirus.

PubMed

Trenado, Helena P; Orílio, Anelise F; Márquez-Martín, Belén; Moriones, Enrique; Navas-Castillo, Jesús

2011-01-01

Sweet potato (Ipomoea batatas) and related Ipomoea species are frequently infected by monopartite begomoviruses (genus Begomovirus, family Geminiviridae), known as sweepoviruses. Unlike other geminiviruses, the genomes of sweepoviruses have been recalcitrant to rendering infectious clones to date. Thus, Koch's postulates have not been fullfilled for any of the viruses in this group. Three novel species of sweepoviruses have recently been described in Spain: Sweet potato leaf curl Lanzarote virus (SPLCLaV), Sweet potato leaf curl Spain virus (SPLCSV) and Sweet potato leaf curl Canary virus (SPLCCaV). Here we describe the generation of the first infectious clone of an isolate (ES:MAL:BG30:06) of SPLCLaV. The clone consisted of a complete tandem dimeric viral genome in a binary vector. Successful infection by agroinoculation of several species of Ipomoea (including sweet potato) and Nicotiana benthamiana was confirmed by PCR, dot blot and Southern blot hybridization. Symptoms observed in infected plants consisted of leaf curl, yellowing, growth reduction and vein yellowing. Two varieties of sweet potato, 'Beauregard' and 'Promesa', were infected by agroinoculation, and symptoms of leaf curl and interveinal loss of purple colouration were observed, respectively. The virus present in agroinfected plants was readily transmitted by the whitefly Bemisia tabaci to I. setosa plants. The progeny virus population present in agroinfected I. setosa and sweet potato plants was isolated and identity to the original isolate was confirmed by sequencing. Therefore, Koch's postulates were fulfilled for the first time for a sweepovirus.

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

Vitvitsky, Victor; Yadav, Pramod K.; An, Sojin

Hydrogen sulfide is a cardioprotective signaling molecule but is toxic at elevated concentrations. Red blood cells can synthesize H2S but, lacking organelles, cannot dispose of H2S via the mitochondrial sulfide oxidation pathway. We have recently shown that at high sulfide concentrations, ferric hemoglobin oxidizes H2S to a mixture of thiosulfate and iron-bound polysulfides in which the latter species predominates. Here, we report the crystal structure of human hemoglobin containing low spin ferric sulfide, the first intermediate in heme-catalyzed sulfide oxidation. The structure provides molecular insights into why sulfide is susceptible to oxidation in human hemoglobin but is stabilized against itmore » in HbI, a specialized sulfide-carrying hemoglobin from a mollusk adapted to life in a sulfide-rich environment. We have also captured a second sulfide bound at a postulated ligand entry/exit site in the α-subunit of hemoglobin, which, to the best of our knowledge, represents the first direct evidence for this site being used to access the heme iron. Hydrodisulfide, a postulated intermediate at the junction between thiosulfate and polysulfide formation, coordinates ferric hemoglobin and, in the presence of air, generated thiosulfate. At low sulfide/heme iron ratios, the product distribution between thiosulfate and iron-bound polysulfides was approximately equal. The iron-bound polysulfides were unstable at physiological glutathione concentrations and were reduced with concomitant formation of glutathione persulfide, glutathione disulfide, and H2S. Hence, although polysulfides are unlikely to be stable in the reducing intracellular milieu, glutathione persulfide could serve as a persulfide donor for protein persulfidation, a posttranslational modification by which H2S is postulated to signal.« less

ACCESS 3. Approximation concepts code for efficient structural synthesis: User's guide

NASA Technical Reports Server (NTRS)

Fleury, C.; Schmit, L. A., Jr.

1980-01-01

A user's guide is presented for ACCESS-3, a research oriented program which combines dual methods and a collection of approximation concepts to achieve excellent efficiency in structural synthesis. The finite element method is used for structural analysis and dual algorithms of mathematical programming are applied in the design optimization procedure. This program retains all of the ACCESS-2 capabilities and the data preparation formats are fully compatible. Four distinct optimizer options were added: interior point penalty function method (NEWSUMT); second order primal projection method (PRIMAL2); second order Newton-type dual method (DUAL2); and first order gradient projection-type dual method (DUAL1). A pure discrete and mixed continuous-discrete design variable capability, and zero order approximation of the stress constraints are also included.

A comparative study of inter-abutment distance of dies made from full arch dual-arch impression trays with those made from full arch stock trays: an in vitro study.

PubMed

Reddy, Jagan Mohan; Prashanti, E; Kumar, G Vinay; Suresh Sajjan, M C; Mathew, Xavier

2009-01-01

The dual-arch impression technique is convenient in that it makes the required maxillary and mandibular impressions, as well as the inter-occlusal record in one procedure. The accuracy of inter-abutment distance in dies fabricated from dual-arch impression technique remains in question because there is little information available in the literature. This study was conducted to evaluate the accuracy of inter-abutment distance in dies obtained from full arch dual-arch trays with those obtained from full arch stock metal trays. The metal dual-arch trays showed better accuracy followed by the plastic dual-arch and stock dentulous trays, respectively, though statistically insignificant. The pouring sequence did not have any effect on the inter-abutment distance statistically, though pouring the non-working side of the dual-arch impression first showed better accuracy.

Gravity-induced absorption changes in Phycomyces blakesleeanus during parabolic flights: first spectral approach in the visible.

PubMed

Schmidt, Werner

2006-12-01

Gravity-induced absorption changes as experienced during a series of parabolas on the Airbus 300 Zero-G have been measured previously pointwise on the basis of dual-wavelength spectroscopy. Only the two wavelengths of 460 and 665 nm as generated by light-emitting diodes have been utilised during our first two parabolic-flight campaigns. In order to gain complete spectral information throughout the wavelength range from 400 to 900 nm, a miniaturized rapid scan spectrophotometer was designed. The difference of spectra taken at 0 g and 1.8 g presents the first gravity-induced absorption change spectrum measured on wild-type Phycomyces blakesleeanus sporangiophores, exhibiting a broad positive hump in the visible range and negative values in the near infrared with an isosbestic point near 735 nm. The control experiment performed with the stiff mutant A909 of Phycomyces blakesleeanus does not show this structure. These results are in agreement with those obtained with an array spectrophotometer. In analogy to the more thoroughly understood so-called light-induced absorption changes, we assume that gravity-induced absorption changes reflect redox changes of electron transport components such as flavins and cytochromes localised within the plasma membrane.

Approaching the basis set limit for DFT calculations using an environment-adapted minimal basis with perturbation theory: Formulation, proof of concept, and a pilot implementation

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

Mao, Yuezhi; Horn, Paul R.; Mardirossian, Narbe

2016-07-28

Recently developed density functionals have good accuracy for both thermochemistry (TC) and non-covalent interactions (NC) if very large atomic orbital basis sets are used. To approach the basis set limit with potentially lower computational cost, a new self-consistent field (SCF) scheme is presented that employs minimal adaptive basis (MAB) functions. The MAB functions are optimized on each atomic site by minimizing a surrogate function. High accuracy is obtained by applying a perturbative correction (PC) to the MAB calculation, similar to dual basis approaches. Compared to exact SCF results, using this MAB-SCF (PC) approach with the same large target basis set producesmore » <0.15 kcal/mol root-mean-square deviations for most of the tested TC datasets, and <0.1 kcal/mol for most of the NC datasets. The performance of density functionals near the basis set limit can be even better reproduced. With further improvement to its implementation, MAB-SCF (PC) is a promising lower-cost substitute for conventional large-basis calculations as a method to approach the basis set limit of modern density functionals.« less

Nonlinear Cross-Bridge Elasticity and Post-Power-Stroke Events in Fast Skeletal Muscle Actomyosin

PubMed Central

Persson, Malin; Bengtsson, Elina; ten Siethoff, Lasse; Månsson, Alf

2013-01-01

Generation of force and movement by actomyosin cross-bridges is the molecular basis of muscle contraction, but generally accepted ideas about cross-bridge properties have recently been questioned. Of the utmost significance, evidence for nonlinear cross-bridge elasticity has been presented. We here investigate how this and other newly discovered or postulated phenomena would modify cross-bridge operation, with focus on post-power-stroke events. First, as an experimental basis, we present evidence for a hyperbolic [MgATP]-velocity relationship of heavy-meromyosin-propelled actin filaments in the in vitro motility assay using fast rabbit skeletal muscle myosin (28–29°C). As the hyperbolic [MgATP]-velocity relationship was not consistent with interhead cooperativity, we developed a cross-bridge model with independent myosin heads and strain-dependent interstate transition rates. The model, implemented with inclusion of MgATP-independent detachment from the rigor state, as suggested by previous single-molecule mechanics experiments, accounts well for the [MgATP]-velocity relationship if nonlinear cross-bridge elasticity is assumed, but not if linear cross-bridge elasticity is assumed. In addition, a better fit is obtained with load-independent than with load-dependent MgATP-induced detachment rate. We discuss our results in relation to previous data showing a nonhyperbolic [MgATP]-velocity relationship when actin filaments are propelled by myosin subfragment 1 or full-length myosin. We also consider the implications of our results for characterization of the cross-bridge elasticity in the filament lattice of muscle. PMID:24138863

Contour Curvature As an Invariant Code for Objects in Visual Area V4

PubMed Central

Pasupathy, Anitha

2016-01-01

Size-invariant object recognition—the ability to recognize objects across transformations of scale—is a fundamental feature of biological and artificial vision. To investigate its basis in the primate cerebral cortex, we measured single neuron responses to stimuli of varying size in visual area V4, a cornerstone of the object-processing pathway, in rhesus monkeys (Macaca mulatta). Leveraging two competing models for how neuronal selectivity for the bounding contours of objects may depend on stimulus size, we show that most V4 neurons (∼70%) encode objects in a size-invariant manner, consistent with selectivity for a size-independent parameter of boundary form: for these neurons, “normalized” curvature, rather than “absolute” curvature, provided a better account of responses. Our results demonstrate the suitability of contour curvature as a basis for size-invariant object representation in the visual cortex, and posit V4 as a foundation for behaviorally relevant object codes. SIGNIFICANCE STATEMENT Size-invariant object recognition is a bedrock for many perceptual and cognitive functions. Despite growing neurophysiological evidence for invariant object representations in the primate cortex, we still lack a basic understanding of the encoding rules that govern them. Classic work in the field of visual shape theory has long postulated that a representation of objects based on information about their bounding contours is well suited to mediate such an invariant code. In this study, we provide the first empirical support for this hypothesis, and its instantiation in single neurons of visual area V4. PMID:27194333

Dual Method Use Among a Sample of First-Year College Women

PubMed Central

Walsh, Jennifer L.; Fielder, Robyn L.; Carey, Kate B.; Carey, Michael P.

2014-01-01

CONTEXT Dual method use—using one type of contraceptive to reduce the risk of STDs and another to prevent pregnancy—is effective but understudied. No prior studies have employed an event-level approach to examining characteristics associated with dual method use among college women. METHODS In 12 consecutive monthly surveys conducted in 2009–2010, data on 1,843 vaginal intercourse events were collected from 296 first-year college women. Women reported on their use of condoms and hormonal contraceptives during all events. Multilevel regression analysis was used to assess associations between event-, month- and person-level characteristics and hormonal use and dual method use. RESULTS Women used hormonal contraceptives during 53% of events and condoms during 63%. Dual method use was reported 28% of the time, and only 14% of participants were consistent users of both methods. The likelihood of dual method use was elevated when sex partners were friends as opposed to romantic partners or ex-boyfriends, and among women who had received an STD diagnosis prior to college (odds ratios, 2.5–2.9); it also increased with level of religiosity (coefficient, 0.8). Dual use was less likely when less reliable methods were used (odds ratio, 0.2) and when women reported more months of hormonal use (0.8), were older (coefficient, −4.7) and had had a greater number of partners before college (−0.3). CONCLUSIONS A better understanding of the characteristics associated with dual method use may help in the design of potential intervention efforts. PMID:24684480

Toward a New Theory for Selecting Instructional Visuals.

ERIC Educational Resources Information Center

Croft, Richard S.; Burton, John K.

This paper provides a rationale for the selection of illustrations and visual aids for the classroom. The theories that describe the processing of visuals are dual coding theory and cue summation theory. Concept attainment theory offers a basis for selecting which cues are relevant for any learning task which includes a component of identification…

26 CFR 1.1503(d)-3 - Foreign use.

Code of Federal Regulations, 2010 CFR

2010-04-01

... States) on its worldwide income or on a residence basis. (ii) The loss may be available to offset income... (for example, the United States). (iii) The deductibility of any portion of a deduction or loss taken... general. Except as provided in paragraph (c) of this section, a foreign use of a dual consolidated loss...

Postsecondary Enrollment Options (PSEO) Reference Guide

ERIC Educational Resources Information Center

Minnesota Department of Education, 2017

2017-01-01

The PSEO program is a dual credit program that allows high school students to simultaneously earn high school and college credit through enrollment in and successful completion of college-level courses on a college campus or online. Students may take PSEO courses on a full- or part-time basis. The PSEO program provides students with a greater…

An fMRI Investigation of Posttraumatic Flashbacks

ERIC Educational Resources Information Center

Whalley, Matthew G.; Kroes, Marijn C. W.; Huntley, Zoe; Rugg, Michael D.; Davis, Simon W.; Brewin, Chris R.

2013-01-01

Flashbacks are a defining feature of posttraumatic stress disorder (PTSD), but there have been few studies of their neural basis. We tested predictions from a dual representation model of PTSD that, compared with ordinary episodic memories of the same traumatic event, flashbacks would be associated with activity in dorsal visual stream and related…

Reading and Spelling in Adults: Are There Lexical and Sub-Lexical Subtypes?

ERIC Educational Resources Information Center

Burt, Jennifer S.; Heffernan, Maree E.

2012-01-01

The dual-route model of reading proposes distinct lexical and sub-lexical procedures for word reading and spelling. Lexically reliant and sub-lexically reliant reader subgroups were selected from 78 university students on the basis of their performance on lexical (orthographic) and sub-lexical (phonological) choice tests, and on irregular and…

Taking a Straightforward Detour: Learning and Labour Market Participation in the German Apprenticeship System

ERIC Educational Resources Information Center

Behrens, Martina; Pilz, Matthias; Greuling, Oliver

2008-01-01

In Germany, the group of young people with the most extended transition from school to work are those achieving higher education entrance qualifications ("Abitur"), then serving an apprenticeship in the German "dual system" and later pursuing higher education. On the basis of three Anglo-German comparative studies, this article…

Dual Familial Roles: An Asperger's Syndrome Case Story

ERIC Educational Resources Information Center

Ivey, Julie K.; Ward, A. Kris

2010-01-01

Sibling interactions are challenges that all families face on a daily basis. These interactions are significantly more difficult when one child has autism. With the apparent increase in diagnoses of autism, there are more families each year who are dealing with issues of relationships. Children learn, as part of the growing up experience, how to…

Students' Cognitive Processes While Learning from Teaching. Final Report (Volume One).

ERIC Educational Resources Information Center

Winne, Philip H.; Marx, Ronald W.

Research is reported on the cognitive mediational paradigm which postulates that teachers influence students' learning by causing them to think and behave in particular ways during teaching. Four studies are reported. The first describes five teachers and their students and explores, in classroom lessons, the cognitive processes students used in…

Wilt, crown, and root rot of common rose mallow (Hibiscus moscheutos) caused by a novel Fusarium sp

USDA-ARS?s Scientific Manuscript database

A new crown and root rot disease of landscape plantings of the malvaceous ornamental common rose mallow (Hibiscus moscheutos) was first detected in Washington State in 2012. The main objectives of this study were to complete Koch's postulates, document the disease sypmtoms photographically, and iden...

Occupational health services for shift and night workers.

PubMed

Koller, M

1996-02-01

It is important for an occupational health service to plan health supervision and measures for shift and night workers considering the biorhythmic and psychosocial desynchronisation, as well as the frequent prevalence of combined effects of adverse environmental and working conditions. The measures taken should be preventive to reduce the expected health risks rather than being rehabilitative. Both a medical surveillance and a counselling service are recommended before and during engagement in shift and night work. Sleep, digestive, metabolic and cardiovascular troubles should be noted and followed up. Medical counselling is especially necessary in the first months of shift and night work exposure and then after long-term exposure. The postulate for timed surveillance and intervention is supported by data of our epidemiologic investigations. The importance of the single health measures is underlined by direct reference to the relevant literature. Recommendations that should be applied in all countries and enterprises are in accordance with the ILO Night Work Convention 1990a and include: (1) appropriate occupational health services provided for night and shift workers, including counselling; (2) first aid facilities during all shift hours; (3) the option of transfer to day work when certified unfit for night work for reasons of health; and (4) measures for women on night shifts, in particular special maternity protection (transfer to day work, social security benefits or an extension of maternity leave). Examples of occupational health services already installed in some states for shift and night workers, and information on future developments are given. Up to now the medical service has been implemented mostly on the basis of collective agreements rather than on the basis of legal provisions. The Austrian Night Shift/Heavy Work Law Regulations of 1981, revised 1993, are cited: workers exposed to night shifts under defined single or combined additional heavy workloads are entitled to a special health assessment, additional rest pauses, additional free time and early retirement depending on years of exposure.

Techniques for deriving tissue structure from multiple projection dual-energy x-ray absorptiometry

NASA Technical Reports Server (NTRS)

Feldmesser, Howard S. (Inventor); Charles, Jr., Harry K. (Inventor); Beck, Thomas J. (Inventor); Magee, Thomas C. (Inventor)

2004-01-01

Techniques for deriving bone properties from images generated by a dual-energy x-ray absorptiometry apparatus include receiving first image data having pixels indicating bone mineral density projected at a first angle of a plurality of projection angles. Second image data and third image data are also received. The second image data indicates bone mineral density projected at a different second angle. The third image data indicates bone mineral density projected at a third angle. The third angle is different from the first angle and the second angle. Principal moments of inertia for a bone in the subject are computed based on the first image data, the second image data and the third image data. The techniques allow high-precision, high-resolution dual-energy x-ray attenuation images to be used for computing principal moments of inertia and strength moduli of individual bones, plus risk of injury and changes in risk of injury to a patient.

Creep Deformation and Rupture Behavior of Single- and Dual-Pass 316LN Stainless-Steel-Activated TIG Weld Joints

NASA Astrophysics Data System (ADS)

Vijayanand, V. D.; Vasudevan, M.; Ganesan, V.; Parameswaran, P.; Laha, K.; Bhaduri, A. K.

2016-06-01

Creep deformation and rupture behavior of single-pass and dual-pass 316LN stainless steel (SS) weld joints fabricated by an autogenous activated tungsten inert gas welding process have been assessed by performing metallography, hardness, and conventional and impression creep tests. The fusion zone of the single-pass joint consisted of columnar zones adjacent to base metals with a central equiaxed zone, which have been modified extensively by the thermal cycle of the second pass in the dual-pass joint. The equiaxed zone in the single-pass joint, as well as in the second pass of the dual-pass joint, displayed the lowest hardness in the joints. In the dual-pass joint, the equiaxed zone of the first pass had hardness comparable to the columnar zone. The hardness variations in the joints influenced the creep deformation. The equiaxed and columnar zone in the first pass of the dual-pass joint was more creep resistant than that of the second pass. Both joints possessed lower creep rupture life than the base metal. However, the creep rupture life of the dual-pass joint was about twofolds more than that of the single-pass joint. Creep failure in the single-pass joint occurred in the central equiaxed fusion zone, whereas creep cavitation that originated in the second pass was blocked at the weld pass interface. The additional interface and strength variation between two passes in the dual-pass joint provides more restraint to creep deformation and crack propagation in the fusion zone, resulting in an increase in the creep rupture life of the dual-pass joint over the single-pass joint. Furthermore, the differences in content, morphology, and distribution of delta ferrite in the fusion zone of the joints favors more creep cavitation resistance in the dual-pass joint over the single-pass joint with the enhancement of creep rupture life.

Nonequilibrium Phase Transitions and a Nonequilibrium Critical Point from Anti-de Sitter Space and Conformal Field Theory Correspondence

NASA Astrophysics Data System (ADS)

Nakamura, Shin

2012-09-01

We find novel phase transitions and critical phenomena that occur only outside the linear-response regime of current-driven nonequilibrium states. We consider the strongly interacting (3+1)-dimensional N=4 large-Nc SU(Nc) supersymmetric Yang-Mills theory with a single flavor of fundamental N=2 hypermultiplet as a microscopic theory. We compute its nonlinear nonballistic quark-charge conductivity by using the AdS/CFT correspondence. We find that the system exhibits a novel nonequilibrium first-order phase transition where the conductivity jumps and the sign of the differential conductivity flips at finite current density. A nonequilibrium critical point is discovered at the end point of the first-order regime. We propose a nonequilibrium steady-state analogue of thermodynamic potential in terms of the gravity-dual theory in order to define the transition point. Nonequilibrium analogues of critical exponents are proposed as well. The critical behavior of the conductivity is numerically confirmed on the basis of these proposals. The present work provides a new example of nonequilibrium phase transitions and nonequilibrium critical points.

Interrogation of weak Bragg grating sensors based on dual-wavelength differential detection.

PubMed

Cheng, Rui; Xia, Li

2016-11-15

It is shown that for weak Bragg gratings the logarithmic ratio of reflected intensities at any two wavelengths within the spectrum follows a linear relationship with the Bragg wavelength shift, with a slope proportional to their wavelength spacing. This finding is exploited to develop a flexible, efficient, and cheap interrogation solution of weak fiber Bragg grating (FBGs), especially ultra-short FBGs, in distributed sensing based on dual-wavelength differential detection. The concept is experimentally studied in both single and distributed sensing systems with ultra-short FBG sensors. The work may form the basis of new and promising FBG interrogation techniques based on detecting discrete rather than continuous spectra.

Advances in spaceborne synthetic aperture radar sensor technology

NASA Technical Reports Server (NTRS)

Caro, E. R.; Ruzek, M.

1986-01-01

The evolution of space SARs for NASA projects since Seasat (1978) is surveyed, with an emphasis on hardware development. The fundamental principles of SAR are reviewed; the SIR-A and SIR-B instruments flown as Shuttle payloads are characterized; their antennas, transmitters, receivers, and data subsystems are described; the advantages offered by the SIR-C dual-frequency (L and C band) dual-polarization distributed SAR (being developed for a future Shuttle flight and as the basis of an SAR for the Earth Observing System) are explained; and a number of technical challenges are identified (including RF elements, structural fidelity, pointing accuracy, data handling, and dc power). Drawings, diagrams, sample images, photographs, and tables are provided.

Using CCT Diagrams to Optimize the Composition of an As-Rolled Dual-Phase Steel

NASA Astrophysics Data System (ADS)

Coldren, A. Phillip; Eldis, George T.

1980-03-01

A continuous-cooling transformation (CCT) diagram study was conducted for the purpose of optimizing the composition of a Mn-Si-Cr-Mo as-rolled dual-phase (ARDP) steel. The individual effects of chromium, molybdenum, and silicon on the allowable cooling rates were determined. On the basis of the CCT diagram study and other available information, an optimum composition was selected. Data from recent mill trials at three steel companies, involving steels with compositions in or near the newly recommended range, are presented and compared with earlier mill trial data. The comparison shows that the optimized composition is highly effective in making the steel's properties more uniform and reproducible in the as-rolled condition.

Improving Dual-Task Control With a Posture-Second Strategy in Early-Stage Parkinson Disease.

PubMed

Huang, Cheng-Ya; Chen, Yu-An; Hwang, Ing-Shiou; Wu, Ruey-Meei

2018-03-31

To examine the task prioritization effects on postural-suprapostural dual-task performance in patients with early-stage Parkinson disease (PD) without clinically observed postural symptoms. Cross-sectional study. Participants performed a force-matching task while standing on a mobile platform, and were instructed to focus their attention on either the postural task (posture-first strategy) or the force-matching task (posture-second strategy). University research laboratory. Individuals (N=16) with early-stage PD who had no clinically observed postural symptoms. Not applicable. Dual-task change (DTC; percent change between single-task and dual-task performance) of posture error, posture approximate entropy (ApEn), force error, and reaction time (RT). Positive DTC values indicate higher postural error, posture ApEn, force error, and force RT during dual-task conditions compared with single-task conditions. Compared with the posture-first strategy, the posture-second strategy was associated with smaller DTC of posture error and force error, and greater DTC of posture ApEn. In contrast, greater DTC of force RT was observed under the posture-second strategy. Contrary to typical recommendations, our results suggest that the posture-second strategy may be an effective dual-task strategy in patients with early-stage PD who have no clinically observed postural symptoms in order to reduce the negative effect of dual tasking on performance and facilitate postural automaticity. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Hollow fiber membranes and methods for forming same

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

Bhandari, Dhaval Ajit; McCloskey, Patrick Joseph; Howson, Paul Edward

2016-03-22

The invention provides improved hollow fiber membranes having at least two layers, and methods for forming the same. The methods include co-extruding a first composition, a second composition, and a third composition to form a dual layer hollow fiber membrane. The first composition includes a glassy polymer; the second composition includes a polysiloxane; and the third composition includes a bore fluid. The dual layer hollow fiber membranes include a first layer and a second layer, the first layer being a porous layer which includes the glassy polymer of the first composition, and the second layer being a polysiloxane layer whichmore » includes the polysiloxane of the second composition.« less

Quantum interference experiments with large molecules

NASA Astrophysics Data System (ADS)

Nairz, Olaf; Arndt, Markus; Zeilinger, Anton

2003-04-01

Wave-particle duality is frequently the first topic students encounter in elementary quantum physics. Although this phenomenon has been demonstrated with photons, electrons, neutrons, and atoms, the dual quantum character of the famous double-slit experiment can be best explained with the largest and most classical objects, which are currently the fullerene molecules. The soccer-ball-shaped carbon cages C60 are large, massive, and appealing objects for which it is clear that they must behave like particles under ordinary circumstances. We present the results of a multislit diffraction experiment with such objects to demonstrate their wave nature. The experiment serves as the basis for a discussion of several quantum concepts such as coherence, randomness, complementarity, and wave-particle duality. In particular, the effect of longitudinal (spectral) coherence can be demonstrated by a direct comparison of interferograms obtained with a thermal beam and a velocity selected beam in close analogy to the usual two-slit experiments using light.

1995 Pacific Northwest Loads and Resources Study, Technical Appendix: Volume 1.

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

United States. Bonneville Power Administration.

1995-12-01

The Pacific Northwest Loads and Resources Study (WhiteBook), is published annually by BPA, and establishes the planning basis for supplying electricity to customers. It serves a dual purpose. First, the White Book presents projections of regional and Federal system load and resource capabilities, along with relevant definitions and explanations. Second, the White Book serves as a benchmark for annual BPA determinations made pursuant to the 1981 regional power sales contracts. Specifically, BPA uses the, information in the White Book for determining the notice required when customers request to increase or decrease the amount of power purchased from BPA. Aside frommore » these purposes, the White Book is used for input to BPA`s resource planning process. The White Book compiles information obtained from several formalized resource planning reports and data submittals, including those from the Northwest Power Planning Council (Council) and the Pacific Northwest Utilities Conference Committee (PNUCC).« less

Reduced Order Modeling of Combustion Instability in a Gas Turbine Model Combustor

NASA Astrophysics Data System (ADS)

Arnold-Medabalimi, Nicholas; Huang, Cheng; Duraisamy, Karthik

2017-11-01

Hydrocarbon fuel based propulsion systems are expected to remain relevant in aerospace vehicles for the foreseeable future. Design of these devices is complicated by combustion instabilities. The capability to model and predict these effects at reduced computational cost is a requirement for both design and control of these devices. This work focuses on computational studies on a dual swirl model gas turbine combustor in the context of reduced order model development. Full fidelity simulations are performed utilizing URANS and Hybrid RANS-LES with finite rate chemistry. Following this, data decomposition techniques are used to extract a reduced basis representation of the unsteady flow field. These bases are first used to identify sensor locations to guide experimental interrogations and controller feedback. Following this, initial results on developing a control-oriented reduced order model (ROM) will be presented. The capability of the ROM will be further assessed based on different operating conditions and geometric configurations.

PWR-related integral safety experiments in the PKL 111 test facility SBLOCA under beyond-design-basis accident conditions

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

Weber, P.; Umminger, K.J.; Schoen, B.

1995-09-01

The thermal hydraulic behavior of a PWR during beyond-design-basis accident scenarios is of vital interest for the verification and optimization of accident management procedures. Within the scope of the German reactor safety research program experiments were performed in the volumetrically scaled PKL 111 test facility by Siemens/KWU. This highly instrumented test rig simulates a KWU-design PWR (1300 MWe). In particular, the latest tests performed related to a SBLOCA with additional system failures, e.g. nitrogen entering the primary system. In the case of a SBLOCA, it is the goal of the operator to put the plant in a condition where themore » decay heat can be removed first using the low pressure emergency core cooling system and then the residual heat removal system. The experimental investigation presented assumed the following beyond-design-basis accident conditions: 0.5% break in a cold leg, 2 of 4 steam generators (SGs) isolated on the secondary side (feedwater- and steam line-valves closed), filled with steam on the primary side, cooldown of the primary system using the remaining two steam generators, high pressure injection system only in the two loops with intact steam generators, if possible no operator actions to reach the conditions for residual heat removal system activation. Furthermore, it was postulated that 2 of the 4 hot leg accumulators had a reduced initial water inventory (increased nitrogen inventory), allowing nitrogen to enter the primary system at a pressure of 15 bar and nearly preventing the heat transfer in the SGs ({open_quotes}passivating{close_quotes} U-tubes). Due to this the heat transfer regime in the intact steam generators changed remarkably. The primary system showed self-regulating system effects and heat transfer improved again (reflux-condenser mode in the U-tube inlet region).« less

Coexistence of meningoencephalocele and hippocampal sclerosis: a new type of dual pathology.

PubMed

Martinoni, Matteo; Marucci, Gianluca; Gagliardini, Gabriele; Tinuper, Paolo; Michelucci, Roberto; Giulioni, Marco

2017-05-01

Both temporal lobe meningoencephalocele (TE) and hippocampal sclerosis (HS) are causes of drug-resistant temporal lobe epilepsy. Spontaneous TE constitutes a rare but well-known and increasingly recognised cause of refractory epilepsy. It is well known that HS may be associated with another neocortical lesion (dual pathology). Here we report for the first time a new type of dual pathology; namely, the coexistence of temporal pole meningoencephalocele and HS.

Dual-Task Interference When A Response is Not Required

NASA Technical Reports Server (NTRS)

VanSelst, Mark; Johnston, James C.; Shafto, Michael (Technical Monitor)

2002-01-01

When subjects are required to respond to two stimuli presented in rapid succession, responses to the second stimulus are delayed. Such dual-task interference has been attributed to a fundamental processing bottleneck preventing simultaneous processing on both tasks. Two experiments show dual-task interference even when the first task does not require a response. The observed interference is caused by a bottleneck in central cognitive processing, rather than in response initiation or execution.

A MAG for the Twenty First Century: Lethal, Lighter, Energy Efficient, and Cheaper

DTIC Science & Technology

2010-04-14

well as an advanced trainer. 40 25. Zero altitude-zero airspeed ejection seats . 26. Common multi-function display (MFD) cockpit configuration for...front cockpit, with seat belts/shoulder harnesses fastened. b. Aft cockpit capable of being reconfigured for flight control including conducting...Capability to carry two wounded Marines via internal litters. 24. Dual seat with dual controls to facilitate dual use as light attack/armed reconnaissance as

Dual photon absorptiometry using a gadolinium-153 source applied to measure equine bone mineral content

NASA Astrophysics Data System (ADS)

Moure, Alessandro; Reichmann, Peter; Remigio Gamba, Humberto

2003-12-01

The application of the dual photon absorptiometry (DPA) technique, using gadolinium-153 as the photon source, to evaluate the bone mineral density (BMD) of the third metacarpal bone of horses is presented. The radiation detector was implemented with a NaI(TI) scintillator coupled to a 14 stage photomultiplier. A modular mechanical system allows the position of the prototype to be adjusted in relation to the animal. A moveable carrier makes it possible to scan the third metacarpal with a velocity adjustable between 1 and 12 mm s-1, in steps of 1 mm s-1, for a total distance of 250 mm. The prototype was evaluated with a phantom of the third metacarpal bone made of perspex and aluminium, and in vitro with a transverse slice of the third metacarpal bone of a horse. The tests showed that the prototype has an accuracy and precision of, approximately, 10% and 6%, respectively, for a 6 s acquisition time. Preliminary studies carried out in three foals from birth to one year of age indicated that the prototype is well suited to in vivo and in situ analysis of the BMD of the third metacarpal bones of horses, making it possible to evaluate the changes of BMD levels on a monthly basis. Also, results indicated an exponential behaviour of the BMD curve during the first year of life of the studied horses.

Dual emission behavior of phenyleneethynylene gold(I) complexes dictated by intersystem crossing: a theoretical perspective.

PubMed

Wang, Li; Li, Yuanyuan; Zhang, Yanxin; He, Hongqing; Zhang, Jinglai

2015-02-25

In commonly studied gold(I) complexes with oligo (o-, p-, or m-phenyleneethynylene) (PE) ligands, an intriguing photophysical behavior is dual emission composed of fluorescence from S1 and phosphorescence from T1 which is dictated by effective intersystem crossing (ISC) process. In order to explore the salient photodynamics of such oligo-PE gold(I) complexes effectively, we have deliberately chosen three model complexes, namely, Ph-C≡C-Au(PMe3) (1a') and Ph-C≡C-(1,m)C6H4-C≡C-Au(PMe3) (m=4, 2a'; m=3, 3a') in place of the real system. Firstly, electronic structure methods based on DFT and TD-DFT are utilized to perform optimization calculations for the ground- and lowest-lying excited states, respectively. Next, basic photophysical properties including absorption and emission spectra are investigated by TD-DFT under the optimized geometries. Besides, on the basis of the electronic spectra herein, we succeed in searching for surface intersections as the minima on the seam of singlet-triplet surface crossings (SCs) at the CASSCF level of theory. By integration of the results available, the process of delayed fluorescence of triplet-triplet annihilation (TTA) and phosphorescence was displayed in detail with SCs playing the lead in monitoring the ISC. Copyright © 2014 Elsevier B.V. All rights reserved.

Tips of the dual-lumen microcatheter-facilitated reverse wire technique in percutaneous coronary interventions for markedly angulated bifurcated lesions.

PubMed

Nomura, Tetsuya; Kikai, Masakazu; Hori, Yusuke; Yoshioka, Kenichi; Kubota, Hiroshi; Miyawaki, Daisuke; Urata, Ryota; Sugimoto, Takeshi; Keira, Natsuya; Tatsumi, Tetsuya

2018-04-01

In practical settings of percutaneous coronary intervention (PCI), we sometimes encounter difficulty in introducing a guidewire (GW) to the markedly angulated side branch (SB), and the reverse wire technique is considered as a last resort to overcome such a situation. We analyzed 12 cases that underwent PCI with dual-lumen microcatheter-facilitated reverse wire technique between January 2013 and July 2016. We retrospectively investigated the lesion's characteristics and the details of the PCI procedures, and discussed tips about the use of this technique. The SB that exhibits both a smaller take-off angle and a larger carina angle is considered to be the most suitable candidate for this technique. The first step of this technique involves the delivery of the reverse wire system to the target bifurcation. However, most cases exhibit significant stenosis proximal to the bifurcation, which often hampers the delivery of the reverse wire system. Because the sharply curved reverse wire system is easier to pass the stenosis as compared to the roundly curved system, we recommend a sharp curve should be adopted for this technique. On the other hand, it is sure that device delivery is much easier on the GW with a round curve as compared to that with a sharp curve. Therefore, it is important to modify the details of this procedure on a case-by-case basis according to the lesion's characteristics.

Homophobia: An Impulsive Attraction to the Same Sex? Evidence From Eye-Tracking Data in a Picture-Viewing Task.

PubMed

Cheval, Boris; Radel, Remi; Grob, Emmanuelle; Ghisletta, Paolo; Bianchi-Demicheli, Francesco; Chanal, Julien

2016-05-01

Some models suggest that homophobia can be explained as a denied attraction toward same-sex individuals. While it has been found that homophobic men have same-sex attraction, these results are not consistent. This study drew on the dual-process models to test the assumption that sexual interest in homosexual cues among men high in homophobia will depend on their specific impulses toward homosexual-related stimuli. Heterosexual men (N = 38) first completed a scale measuring their level of homonegativity. Then, they performed a manikin task to evaluate their impulsive approach tendencies toward homosexual stimuli (IAHS). A picture-viewing task was performed with simultaneous eye-tracking recording to assess participants' viewing time of the visual area of interest (i.e., face and body). IAHS positively predicted the viewing time of homosexual photographs among men with a high score of homonegativity. Men with a high homonegativity score looked significantly longer at homosexual than at heterosexual photographs but only when they had a high IAHS. These findings confirm the importance of considering the variability in impulsive processes to understand why some (but not all) men high in homophobia have homosexual interest. These findings reinforce the theoretical basis for elaborating a dual-process model for behaviors in the sexual context. Copyright © 2016 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Dual chamber system providing simultaneous etch and deposition on opposing substrate sides for growing low defect density epitaxial layers

DOEpatents

Kulkarni, Nagraj S [Knoxville, TN; Kasica, Richard J. ,

2011-03-08

A dual-chamber reactor can include a housing enclosing a volume having a divider therein, where the divider defines a first chamber and a second chamber. The divider can include a substrate holder that supports at least one substrate and exposes a first side of the substrate to the first chamber and a second side of the substrate to the second chamber. The first chamber can include an inlet for delivering at least one reagent to the first chamber for forming a film on the first side of the substrate, and the second chamber can include a removal device for removing material from the second side of the substrate.

Advanced Test Reactor Safety Basis Upgrade Lessons Learned Relative to Design Basis Verification and Safety Basis Management

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

G. L. Sharp; R. T. McCracken

The Advanced Test Reactor (ATR) is a pressurized light-water reactor with a design thermal power of 250 MW. The principal function of the ATR is to provide a high neutron flux for testing reactor fuels and other materials. The reactor also provides other irradiation services such as radioisotope production. The ATR and its support facilities are located at the Test Reactor Area of the Idaho National Engineering and Environmental Laboratory (INEEL). An audit conducted by the Department of Energy's Office of Independent Oversight and Performance Assurance (DOE OA) raised concerns that design conditions at the ATR were not adequately analyzedmore » in the safety analysis and that legacy design basis management practices had the potential to further impact safe operation of the facility.1 The concerns identified by the audit team, and issues raised during additional reviews performed by ATR safety analysts, were evaluated through the unreviewed safety question process resulting in shutdown of the ATR for more than three months while these concerns were resolved. Past management of the ATR safety basis, relative to facility design basis management and change control, led to concerns that discrepancies in the safety basis may have developed. Although not required by DOE orders or regulations, not performing design basis verification in conjunction with development of the 10 CFR 830 Subpart B upgraded safety basis allowed these potential weaknesses to be carried forward. Configuration management and a clear definition of the existing facility design basis have a direct relation to developing and maintaining a high quality safety basis which properly identifies and mitigates all hazards and postulated accident conditions. These relations and the impact of past safety basis management practices have been reviewed in order to identify lessons learned from the safety basis upgrade process and appropriate actions to resolve possible concerns with respect to the current ATR safety basis. The need for a design basis reconstitution program for the ATR has been identified along with the use of sound configuration management principles in order to support safe and efficient facility operation.« less

Potential health risks from postulated accidents involving the Pu-238 RTG on the Ulysses solar exploration mission

NASA Technical Reports Server (NTRS)

Goldman, Marvin; Hoover, Mark D.; Nelson, Robert C.; Templeton, William; Bollinger, Lance; Anspaugh, Lynn

1991-01-01

Potential radiation impacts from launch of the Ulysses solar exploration experiment were evaluated using eight postulated accident scenarios. Lifetime individual dose estimates rarely exceeded 1 mrem. Most of the potential health effects would come from inhalation exposures immediately after an accident, rather than from ingestion of contaminated food or water, or from inhalation of resuspended plutonium from contaminated ground. For local Florida accidents (that is, during the first minute after launch), an average source term accident was estimated to cause a total added cancer risk of up to 0.2 deaths. For accidents at later time after launch, a worldwide cancer risk of up to three cases was calculated (with a four in a million probability). Upper bound estimates were calculated to be about 10 times higher.

Volume versus wiring transmission in the brain: a new theoretical frame for neuropsychopharmacology.

PubMed

Agnati, L F; Bjelke, B; Fuxe, K

1995-01-01

A volume transmission mode of communication in brain was implicit already in the early work of Golgi, who postulated the existence of electrical signals in the extracellular fluid (ECF) based on Volta's "wet conductor" made by solutions. The term volume transmission is taken from the term volume conduction describing the flow of ionic currents in the ECF as a basis for the electrocorticogram. The slow VT mode includes also chemical signals and is opposed to the fast synaptic (wiring) transmission. Every neuron may function in a dual mode, the synaptic and the volume transmission mode, when considering the autocrine and synaptic classes of communication. The paracrine- and neuroendocrine-like classes only involve the VT mode in the latter case including the CSF as a route. The chemical signals for VT are the neuropeptides, but also the classical transmitters, the monoamines, acetylcholine, GABA, and glutamate can participate, when they operate via slow, high affinity G protein coupled receptors. Ions such as K+, Ca++, and H+ also function as VT signals. The hypothesis is also introduced that CO2 can act as a multifacit long-distance VT and WT regulator besides being part of the CO2/HCO3 buffer. CO2 via regulating NMDA receptor sensitivity can also regulate NO formation, which represents a paracrine and fast VT signal. The therapy of CNS disorders is also discussed in the frame of the wiring and VT concept. Two therapeutical approaches can therefore be developed, one based on increasing WT and one based on increasing VT. In contrast to the WT therapy, which must preserve the electrotemporal code, the VT therapy can operate also with postsynaptic agonists. Therefore, a therapeutic effect with such a drug indicates that the deficiency in the communication process operates via VT. In view of the lack of very effective negative feedbacks in VT vs. WT, VT therapy may produce less tolerance and drug dependency.

Adaptive Spontaneous Transitions between Two Mechanisms of Numerical Averaging.

PubMed

Brezis, Noam; Bronfman, Zohar Z; Usher, Marius

2015-06-04

We investigated the mechanism with which humans estimate numerical averages. Participants were presented with 4, 8 or 16 (two-digit) numbers, serially and rapidly (2 numerals/second) and were instructed to convey the sequence average. As predicted by a dual, but not a single-component account, we found a non-monotonic influence of set-size on accuracy. Moreover, we observed a marked decrease in RT as set-size increases and RT-accuracy tradeoff in the 4-, but not in the 16-number condition. These results indicate that in accordance with the normative directive, participants spontaneously employ analytic/sequential thinking in the 4-number condition and intuitive/holistic thinking in the 16-number condition. When the presentation rate is extreme (10 items/sec) we find that, while performance still remains high, the estimations are now based on intuitive processing. The results are accounted for by a computational model postulating population-coding underlying intuitive-averaging and working-memory-mediated symbolic procedures underlying analytical-averaging, with flexible allocation between the two.

Advances in our understanding of immunization and vaccines for patients with systemic lupus erythematosus.

PubMed

Bragazzi, Nicola Luigi; Watad, Abdulla; Sharif, Kassem; Adawi, Mohammad; Aljadeff, Gali; Amital, Howard; Shoenfeld, Yehuda

2017-10-01

Systemic lupus erythematosus (SLE) is a chronic systemic autoimmune disease. In SLE, immune system dysfunction is postulated to result by virtue of the disease itself as well as by the impact of treatment modalities employed. A myriad of immune dysregulations occur including complement system dysfunction among others. Infectious agents are known to complicate the disease course in close to 25-45% of SLE patients. Areas covered: In this review a discussion of the immunogenicity and safety of viral and bacterial vaccinations in SLE was performed. The search included ISI Web of Science (WoS), Scopus, MEDLINE/PubMed, Google-Scholar, DOAJ, EbscoHOST, Scirus, Science Direct, Cochrane Library and ProQuest. Proper string made up of a key-words including 'SLE', 'vaccination', 'safety' and 'efficacy' was used. Expert commentary: Vaccination of SLE patients is proven to be immunogenic. Concerns regarding vaccine safety are postulated, yet no direct relationship between vaccination and disease exacerbation were established. While live virus vaccines are generally contraindicated in immunosuppressive states, generally live attenuated vaccinations are recommended in SLE patients on a case-to-case basis. In SLE patients, clinical parameters such as vaccination during disease exacerbations have not been intensively studied and therefore while apparently safe, vaccination is generally recommended while disease is quiescent.

[Interdisciplinary AWMF guideline for the diagnostics of primary immunodeficiency].

PubMed

Farmand, S; Baumann, U; von Bernuth, H; Borte, M; Foerster-Waldl, E; Franke, K; Habermehl, P; Kapaun, P; Klock, G; Liese, J; Marks, R; Müller, R; Nebe, T; Niehues, T; Schuster, V; Warnatz, K; Witte, T; Ehl, S; Schulze, I

2011-11-01

Primary immunodeficiencies are potentially life-threatening diseases. Over the last years, the clinical phenotype and the molecular basis of an increasing number of immunological defects have been characterized. However, in daily practice primary immunodeficiencies are still often diagnosed too late. Considering that an early diagnosis may reduce morbidity and mortality of affected patients, an interdisciplinary guideline for the diagnosis of primary immunodeficiencies was developed on behalf of the Arbeitsgemeinschaft Pädiatrische Immunologie (API) and the Deutsche Gesellschaft für Immunologie (DGfI). The guideline is based on expert opinion and on knowledge from other guidelines and recommendations from Germany and other countries, supplemented by data from studies that support the postulated key messages (level of evidence III). With the contribution of 20 representatives, belonging to 14 different medical societies and associations, a consensus-based guideline with a representative group of developers and a structured consensus process was created (S2k). Under the moderation of a representative of the Association of the Scientific Medical Societies in Germany (AWMF) the nominal group process took place in April 2011. The postulated key messages were discussed and voted on following a structured consensus procedure. In particular, modified warning signs for primary immunodeficiencies were formulated and immunological emergency situations were defined. © Georg Thieme Verlag KG Stuttgart · New York.

A Simple Lab Exercise Demonstrating Koch's Postulates.

ERIC Educational Resources Information Center

Fulton, Michael M.

1981-01-01

Describes a laboratory exercise which applies Koch's Postulates to a plant disease, bacterial speck. Includes an explanation of Koch's Postulate, list of equipment needed, advance preparation, outline of the three-week activity, and variations of the laboratory exercise. (DS)

Political conservatism, authoritarianism, and societal threat: voting for Republican representatives in U.S. Congressional elections from 1946 to 1992.

PubMed

McCann, Stewart J H

2009-07-01

The author found that the degree of national societal threat preceding congressional elections from 1946 to 1992 was positively associated with the mean state percentage of people voting for Republican representatives, supporting a conventional threat-authoritarianism hypothesis. However, threat was positively associated with the mean state percentage of people voting for Republican representatives in conservative states but not in liberal states, and the conventional threat-authoritarianism link was entirely driven by the relation in conservative states. The author classified states with a composite measure (alpha = .92) on the basis of state ideological identification, religious fundamentalism, composite policy liberalism, Republican Party elite ideology, and Democratic Party elite ideology. These results offer support to an interactive threat-authoritarianism hypothesis derived from the authoritarian dynamic theory of K. Stenner (2005), which postulates that only authoritarian persons are activated to manifest authoritarian behavior in times of normative threat. Also, the author discusses potential alternative explanations on the basis of system justification, need for closure, and terror-management theories.

Comparison of veterinary drugs and veterinary homeopathy: part 1

PubMed Central

Lees, P.; Pelligand, L.; Whiting, M.; Chambers, D.; Toutain, P-L.; Whitehead, M. L.

2017-01-01

For many years after its invention around 1796, homeopathy was widely used in people and later in animals. Over the intervening period (1796-2016) pharmacology emerged as a science from Materia Medica (medicinal materials) to become the mainstay of veterinary therapeutics. There remains today a much smaller, but significant, use of homeopathy by veterinary surgeons. Homeopathic products are sometimes administered when conventional drug therapies have not succeeded, but are also used as alternatives to scientifically based therapies and licensed products. The principles underlying the veterinary use of drug-based and homeopathic products are polar opposites; this provides the basis for comparison between them. This two-part review compares and contrasts the two treatment forms in respect of history, constituents, methods of preparation, known or postulated mechanisms underlying responses, the legal basis for use and scientific credibility in the 21st century. Part 1 begins with a consideration of why therapeutic products actually work or appear to do so. PMID:28801498

Hot Cell Installation and Demonstration of the Severe Accident Test Station

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

Linton, Kory D.; Burns, Zachary M.; Terrani, Kurt A.

A Severe Accident Test Station (SATS) capable of examining the oxidation kinetics and accident response of irradiated fuel and cladding materials for design basis accident (DBA) and beyond design basis accident (BDBA) scenarios has been successfully installed and demonstrated in the Irradiated Fuels Examination Laboratory (IFEL), a hot cell facility at Oak Ridge National Laboratory. The two test station modules provide various temperature profiles, steam, and the thermal shock conditions necessary for integral loss of coolant accident (LOCA) testing, defueled oxidation quench testing and high temperature BDBA testing. The installation of the SATS system restores the domestic capability to examinemore » postulated and extended LOCA conditions on spent fuel and cladding and provides a platform for evaluation of advanced fuel and accident tolerant fuel (ATF) cladding concepts. This document reports on the successful in-cell demonstration testing of unirradiated Zircaloy-4. It also contains descriptions of the integral test facility capabilities, installation activities, and out-of-cell benchmark testing to calibrate and optimize the system.« less

Comparison of veterinary drugs and veterinary homeopathy: part 1.

PubMed

Lees, P; Pelligand, L; Whiting, M; Chambers, D; Toutain, P-L; Whitehead, M L

2017-08-12

For many years after its invention around 1796, homeopathy was widely used in people and later in animals. Over the intervening period (1796-2016) pharmacology emerged as a science from Materia Medica (medicinal materials) to become the mainstay of veterinary therapeutics. There remains today a much smaller, but significant, use of homeopathy by veterinary surgeons. Homeopathic products are sometimes administered when conventional drug therapies have not succeeded, but are also used as alternatives to scientifically based therapies and licensed products. The principles underlying the veterinary use of drug-based and homeopathic products are polar opposites; this provides the basis for comparison between them. This two-part review compares and contrasts the two treatment forms in respect of history, constituents, methods of preparation, known or postulated mechanisms underlying responses, the legal basis for use and scientific credibility in the 21st century. Part 1 begins with a consideration of why therapeutic products actually work or appear to do so. British Veterinary Association.

Dual peer mentoring program for undergraduate medical students: exploring the perceptions of mentors and mentees

PubMed Central

Abdolalizadeh, Parya; Pourhassan, Saeed; Gandomkar, Roghayeh; Heidari, Farrokh; Sohrabpour, Amir Ali

2017-01-01

Background: Despite the advantages of dual peer mentoring, there are a few reports of implementing and evaluating such programs for medical students. This study aimed at exploring the perceptions of mentors and mentees about the dual peer mentoring program for the first year undergraduate medical students of Tehran University of Medical Sciences. Methods: This qualitative study was conducted at the end of the first year of implementing the mentoring program. All mentees and mentors were invited to participate in focus group discussions. Data were analyzed using a qualitative content analysis. Results: All mentors (n= 12) and a group of mentees (n= 21) participated in focus group discussion sessions. We provided a variety of supports for the mentees including academic and psychosocial support and positive relationship; as a result, some developments occurred to the mentors We also explored participants’ views on some unique aspects of the program such as student-authorized, dual mentoring, and role model sessions. Conclusion: Our participants found the mentoring program beneficial in various academic achievements and psychosocial supports for both the mentors and the mentees. Dual peer mentoring program can be an alternative to school administered programs. PMID:28638809

Dual peer mentoring program for undergraduate medical students: exploring the perceptions of mentors and mentees.

PubMed

Abdolalizadeh, Parya; Pourhassan, Saeed; Gandomkar, Roghayeh; Heidari, Farrokh; Sohrabpour, Amir Ali

2017-01-01

Background: Despite the advantages of dual peer mentoring, there are a few reports of implementing and evaluating such programs for medical students. This study aimed at exploring the perceptions of mentors and mentees about the dual peer mentoring program for the first year undergraduate medical students of Tehran University of Medical Sciences. Methods: This qualitative study was conducted at the end of the first year of implementing the mentoring program. All mentees and mentors were invited to participate in focus group discussions. Data were analyzed using a qualitative content analysis. Results: All mentors ( n= 12 ) and a group of mentees ( n= 21 ) participated in focus group discussion sessions. We provided a variety of supports for the mentees including academic and psychosocial support and positive relationship; as a result, some developments occurred to the mentors We also explored participants' views on some unique aspects of the program such as student-authorized, dual mentoring, and role model sessions. Conclusion: Our participants found the mentoring program beneficial in various academic achievements and psychosocial supports for both the mentors and the mentees. Dual peer mentoring program can be an alternative to school administered programs.

Design of two-DMD based zoom MW and LW dual-band IRSP using pixel fusion

NASA Astrophysics Data System (ADS)

Pan, Yue; Xu, Xiping; Qiao, Yang

2018-06-01

In order to test the anti-jamming ability of mid-wave infrared (MWIR) and long-wave infrared (LWIR) dual-band imaging system, a zoom mid-wave (MW) and long-wave (LW) dual-band infrared scene projector (IRSP) based on two-digital micro-mirror device (DMD) was designed by using a projection method of pixel fusion. Two illumination systems, which illuminate the two DMDs directly with Kohler telecentric beam respectively, were combined with projection system by a spatial layout way. The distances of projection entrance pupil and illumination exit pupil were also analyzed separately. MWIR and LWIR virtual scenes were generated respectively by two DMDs and fused by a dichroic beam combiner (DBC), resulting in two radiation distributions in projected image. The optical performance of each component was evaluated by ray tracing simulations. Apparent temperature and image contrast were demonstrated by imaging experiments. On the basis of test and simulation results, the aberrations of optical system were well corrected, and the quality of projected image meets test requirements.

Cross-cultural re-entry for missionaries: a new application for the Dual Process Model.

PubMed

Selby, Susan; Clark, Sheila; Braunack-Mayer, Annette; Jones, Alison; Moulding, Nicole; Beilby, Justin

Nearly half a million foreign aid workers currently work worldwide, including over 140,000 missionaries. During re-entry these workers may experience significant psychological distress. This article positions previous research about psychological distress during re-entry, emphasizing loss and grief. At present there is no identifiable theoretical framework to provide a basis for assessment, management, and prevention of re-entry distress in the clinical setting. The development of theoretical concepts and frameworks surrounding loss and grief including the Dual Process Model (DPM) are discussed. All the parameters of the DPM have been shown to be appropriate for the proposed re-entry model, the Dual Process Model applied to Re-entry (DPMR). It is proposed that the DPMR is an appropriate framework to address the processes and strategies of managing re-entry loss and grief. Possible future clinical applications and limitations of the proposed model are discussed. The DPMR is offered for further validation and use in clinical practice.

Interactions between Depression and Facilitation within Neural Networks: Updating the Dual-Process Theory of Plasticity

PubMed Central

Prescott, Steven A.

1998-01-01

Repetitive stimulation often results in habituation of the elicited response. However, if the stimulus is sufficiently strong, habituation may be preceded by transient sensitization or even replaced by enduring sensitization. In 1970, Groves and Thompson formulated the dual-process theory of plasticity to explain these characteristic behavioral changes on the basis of competition between decremental plasticity (depression) and incremental plasticity (facilitation) occurring within the neural network. Data from both vertebrate and invertebrate systems are reviewed and indicate that the effects of depression and facilitation are not exclusively additive but, rather, that those processes interact in a complex manner. Serial ordering of induction of learning, in which a depressing locus precedes the modulatory system responsible for inducing facilitation, causes the facilitation to wane. The parallel and/or serial expression of depression and waning facilitation within the stimulus–response pathway culminates in the behavioral changes that characterize dual-process learning. A mathematical model is presented to formally express and extend understanding of the interactions between depression and facilitation. PMID:10489261

Rate-dependent, Li-ion insertion/deinsertion behavior of LiFePO4 cathodes in commercial 18650 LiFePO4 cells.

PubMed

Liu, Qi; He, Hao; Li, Zhe-Fei; Liu, Yadong; Ren, Yang; Lu, Wenquan; Lu, Jun; Stach, Eric A; Xie, Jian

2014-03-12

We have performed operando synchrotron high-energy X-ray diffraction (XRD) to obtain nonintrusive, real-time monitoring of the dynamic chemical and structural changes in commercial 18650 LiFePO4/C cells under realistic cycling conditions. The results indicate a nonequilibrium lithium insertion and extraction in the LiFePO4 cathode, with neither the LiFePO4 phase nor the FePO4 phase maintaining a static composition during lithium insertion/extraction. On the basis of our observations, we propose that the LiFePO4 cathode simultaneously experiences both a two-phase reaction mechanism and a dual-phase solid-solution reaction mechanism over the entire range of the flat voltage plateau, with this dual-phase solid-solution behavior being strongly dependent on charge/discharge rates. The proposed dual-phase solid-solution mechanism may explain the remarkable rate capability of LiFePO4 in commercial cells.

Dual adaptive dynamic control of mobile robots using neural networks.

PubMed

Bugeja, Marvin K; Fabri, Simon G; Camilleri, Liberato

2009-02-01

This paper proposes two novel dual adaptive neural control schemes for the dynamic control of nonholonomic mobile robots. The two schemes are developed in discrete time, and the robot's nonlinear dynamic functions are assumed to be unknown. Gaussian radial basis function and sigmoidal multilayer perceptron neural networks are used for function approximation. In each scheme, the unknown network parameters are estimated stochastically in real time, and no preliminary offline neural network training is used. In contrast to other adaptive techniques hitherto proposed in the literature on mobile robots, the dual control laws presented in this paper do not rely on the heuristic certainty equivalence property but account for the uncertainty in the estimates. This results in a major improvement in tracking performance, despite the plant uncertainty and unmodeled dynamics. Monte Carlo simulation and statistical hypothesis testing are used to illustrate the effectiveness of the two proposed stochastic controllers as applied to the trajectory-tracking problem of a differentially driven wheeled mobile robot.

The effect of dual tasking on foot kinematics in people with functional ankle instability.

PubMed

Tavakoli, Sanam; Forghany, Saeed; Nester, Christopher

2016-09-01

Some cases of repeated inversion ankle sprains are thought to have a neurological basis and are termed functional ankle instability (FAI). In addition to factors local to the ankle, such as loss of proprioception, cognitive demands have the ability to influence motor control and may increase the risk of repetitive lateral sprains. The purpose of this study was to investigate the effect of cognitive demand on foot kinematics in physically active people with functional ankle instability. 21 physically active participants with FAI and 19 matched healthy controls completed trials of normal walking (single task) and normal walking while performing a cognitive task (dual task). Foot motion relative to the shank was recorded. Cognitive performance, ankle kinematics and movement variability in single and dual task conditions was characterized. During normal walking, the ankle joint was significantly more inverted in FAI compared to the control group pre and post initial contact. Under dual task conditions, there was a statistically significant increase in frontal plane foot movement variability during the period 200ms pre and post initial contact in people with FAI compared to the control group (p<0.05). Dual task also significantly increased plantar flexion and inversion during the period 200ms pre and post initial contact in the FAI group (p<0.05). participants with FAI demonstrated different ankle movement patterns and increased movement variability during a dual task condition. Cognitive load may increase risk of ankle instability in these people. Copyright © 2016 Elsevier B.V. All rights reserved.

Fear of falling is associated with prolonged anticipatory postural adjustment during gait initiation under dual-task conditions in older adults.

PubMed

Uemura, Kazuki; Yamada, Minoru; Nagai, Koutatsu; Tanaka, Buichi; Mori, Shuhei; Ichihashi, Noriaki

2012-02-01

Little is known about dynamic balance control under dual-task conditions in older adults with fear of falling (FoF). The purpose of this study was to examine the effect of FoF on anticipatory postural adjustment (APA) during gait initiation under dual-task conditions in older adults. Fifty-seven elderly volunteers (age, 79.2 [6.8] years) from the community participated in this study. Each participant was categorised into either the Fear (n=24) or No-fear (n=33) group on the basis of the presence or absence of FoF. Under single- and dual-task conditions, centre of pressure (COP) data were collected while the participants performed gait initiation trials from a starting position on a force platform. We also performed a 10-m walking test (WT), a timed up & go test (TUG), and a functional reach test (FR). The reaction and APA phases were measured from the COP data. The results showed that under the dual-task condition, the Fear group had significantly longer APA phases than the No-fear group, although no significant differences were observed between the 2 groups in the reaction and APA phases under the single-task condition and in any clinical measurements (WT, TUG, and FR). Our findings suggest that specific deficits in balance control occur in subjects with FoF during gait initiation while dual tasking, even if their physical functions are comparable to subjects without FoF. Copyright © 2011 Elsevier B.V. All rights reserved.

Conceptual DFT: the chemical relevance of higher response functions.

PubMed

Geerlings, P; De Proft, F

2008-06-07

In recent years conceptual density functional theory offered a perspective for the interpretation/prediction of experimental/theoretical reactivity data on the basis of a series of response functions to perturbations in the number of electrons and/or external potential. This approach has enabled the sharp definition and computation, from first principles, of a series of well-known but sometimes vaguely defined chemical concepts such as electronegativity and hardness. In this contribution, a short overview of the shortcomings of the simplest, first order response functions is illustrated leading to a description of chemical bonding in a covalent interaction in terms of interacting atoms or groups, governed by electrostatics with the tendency to polarize bonds on the basis of electronegativity differences. The second order approach, well known until now, introduces the hardness/softness and Fukui function concepts related to polarizability and frontier MO theory, respectively. The introduction of polarizability/softness is also considered in a historical perspective in which polarizability was, with some exceptions, mainly put forward in non covalent interactions. A particular series of response functions, arising when the changes in the external potential are solely provoked by changes in nuclear configurations (the "R-analogues") are also systematically considered. The main part of the contribution is devoted to third order response functions which, at first sight, may be expected not to yield chemically significant information, as turns out to be for the hyperhardness. A counterexample is the dual descriptor and its R analogue, the initial hardness response, which turns out to yield a firm basis to regain the Woodward-Hoffmann rules for pericyclic reactions based on a density-only basis, i.e. without involving the phase, sign, symmetry of the wavefunction. Even the second order nonlinear response functions are shown possibly to bear interesting information, e.g. on the local and global polarizability. Its derivatives may govern the influence of charge on the polarizability, the R-analogues being the nuclear Fukui function and the quadratic and cubic force constants. Although some of the higher order derivatives may be difficult to evaluate a comparison with the energy expansion used in spectroscopy in terms of nuclear displacements, nuclear magnetic moments, electric and magnetic fields leads to the conjecture that, certainly cross terms may contain new, intricate information for understanding chemical reactivity.

Dual Antiplatelet Therapy for 6 Months vs 12 Months After New-generation Drug-eluting Stent Implantation: Matched Analysis of ESTROFA-DAPT and ESTROFA-2.

PubMed

de la Torre Hernández, José M; Oteo Domínguez, Juan F; Hernández, Felipe; García Camarero, Tamara; Abdul-Jawad Altisent, Omar; Rivero Crespo, Fernando; Cascón, José D; Zavala, Germán; Gimeno, Federico; Arrebola Moreno, Antonio L; Andraka, Leire; Gómez Menchero, Antonio; Bosa, Francisco; Carrillo, Xavier; Sánchez Recalde, Ángel; Alfonso, Fernando; Pérez de Prado, Armando; López Palop, Ramón; Sanchis, Juan; Diarte de Miguel, José A; Jiménez Navarro, Manuel; Muñoz, Luz; Ramírez Moreno, Antonio; Tizón Marcos, Helena

2015-10-01

The recommendation for dual antiplatelet therapy following drug-eluting stent implantation ranges from 6 months to 12 months or beyond. Recent trials have suggested the safety of a 6-month dual antiplatelet therapy regimen, yet certain caveats to these studies limit the applicability of this shorter duration dual antiplatelet therapy strategy in real world settings. A registry was constructed with consecutive recruitment of patients undergoing new-generation drug-eluting stent implantation and prescribed 6 months of dual antiplatelet therapy. Propensity score matching was undertaken with a historical cohort of patients treated with second-generation drug-eluting stents who received 12 months of dual antiplatelet therapy from the ESTROFA-2 registry. The sample size was calculated using a noninferiority basis and the primary endpoint was the combination of cardiac death, myocardial infarction, revascularization, or major bleeding at 12 months. The analysis included 1286 patients in each group, with no significant differences in baseline characteristics. The primary endpoint occurred in 5.0% and 6.6% in the 6-month and 12-month groups, respectively (P = .001 for noninferiority). The incidence of definite or probable stent thrombosis was 0.5% and 0.7% in the 6-month and 12-month groups, respectively (P = .4). Major bleeding events were lower in the 6-month group than in the 12-month group (0.8% vs 1.4%; P = .2) CONCLUSIONS: In selected patients in this large multicenter study, the safety and efficacy of a 6-month dual antiplatelet therapy regimen after implantation of new-generation drug-eluting stents appeared to be noninferior to those of a 12-month dual antiplatelet therapy regimen. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Eliminating Barriers to Dual Enrollment in Oklahoma

ERIC Educational Resources Information Center

Roach, Rick; Gamez Vargas, Juanita; David, Kevin M.

2015-01-01

Policy, financial, and transportation barriers have limited participation in dual enrollment for marginalized (low-socioeconomic, first-generation, and ethnic minority) students in Oklahoma. This chapter presents a collaborative effort by education and community leaders that has successfully eliminated these barriers and increased the number of…

Microprocessor controlled advanced battery management systems

NASA Technical Reports Server (NTRS)

Payne, W. T.

1978-01-01

The advanced battery management system described uses the capabilities of an on-board microprocessor to: (1) monitor the state of the battery on a cell by cell basis; (2) compute the state of charge of each cell; (3) protect each cell from reversal; (4) prevent overcharge on each individual cell; and (5) control dual rate reconditioning to zero volts per cell.

Empirical Study of the Role of Government Support and Success Factors in Industry-University-Institute Cooperation

ERIC Educational Resources Information Center

Zhimin, Guan; Zhongpeng, Cao; Jin, Tao

2016-01-01

Empirical research methods were used to study the state of industry-university-institute collaboration in China and the factors influencing the results of cooperation between members of technological innovation alliances, from the dual perspectives of enterprises and universities/research institutes On the basis of questionnaire surveys of 100…

On the geometric analysis and adjustment of optical satellite observations. M.S. Thesis

NASA Technical Reports Server (NTRS)

Tsimis, E.

1972-01-01

Satellite geodesy methods were catagorized into three divisions: geometric, dynamic, and mixed. These catagories furnish the basis for distinction between geometric and dynamic satellite geodesy. The dual adjustment, geometric analysis, and Cartesian coodinate determination are examined for two observing stations. Similar illustrations are given when more than two observing stations are used.

The adolescent parent: A dual developmental crisis.

PubMed

Sadler, L S; Catrone, C

1983-06-01

This paper examines salient developmental characteristics of adolescents and beginning parents. In the case of many teenage parents, specific developmental tasks of adolescence affect and may potentially conflict with the tasks of early parenthood. A conceptual framework is presented which describes this conflict and serves as the basis for examining and explaining certain unique behaviors observed in young adolescent parents.

Seed and blanket fuel arrangement for dual-phase nuclear reactors

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

Congdon, S.P.; Fawcett, R.M.

1992-09-22

This patent describes a fuel management method for a dual-phase nuclear reactor, it comprises: installing a fuel bundle at a first core location accessed by coolant through a relatively small aperture, each of the bundles having a predetermined group of fuel elements; operating the reactor a first time; shutting down the reactor; reinstalling the fuel bundle at a second core location accessed by coolant through a relatively large aperture; and operating the reactor a second time.

Achieving Academic Control in Two Languages: Drawing on the Psychology of Language Learning in Considering the Past, the Present, and Prospects for the Future

ERIC Educational Resources Information Center

Cohen, Andrew D.

2015-01-01

This paper first considers what it means to become truly proficient in a language other than the native one. It then looks briefly at the evolution of dual language programs. Next, it focuses on the issue of whether the first language (L1) or the second language (L2) serves as the language of mediation. Other dual language program issues are then…

Inorganic dual-layer microporous supported membranes

DOEpatents

Brinker, C. Jeffrey; Tsai, Chung-Yi; Lu, Yungfeng

2003-03-25

The present invention provides for a dual-layer inorganic microporous membrane capable of molecular sieving, and methods for production of the membranes. The inorganic microporous supported membrane includes a porous substrate which supports a first inorganic porous membrane having an average pore size of less than about 25 .ANG. and a second inorganic porous membrane coating the first inorganic membrane having an average pore size of less than about 6 .ANG.. The dual-layered membrane is produced by contacting the porous substrate with a surfactant-template polymeric sol, resulting in a surfactant sol coated membrane support. The surfactant sol coated membrane support is dried, producing a surfactant-templated polymer-coated substrate which is calcined to produce an intermediate layer surfactant-templated membrane. The intermediate layer surfactant-templated membrane is then contacted with a second polymeric sol producing a polymeric sol coated substrate which is dried producing an inorganic polymeric coated substrate. The inorganic polymeric coated substrate is then calcined producing an inorganic dual-layered microporous supported membrane in accordance with the present invention.

Economic Efficiency and Investment Timing for Dual Water Systems

NASA Astrophysics Data System (ADS)

Leconte, Robert; Hughes, Trevor C.; Narayanan, Rangesan

1987-10-01

A general methodology to evaluate the economic feasibility of dual water systems is presented. In a first step, a static analysis (evaluation at a single point in time) is developed. The analysis requires the evaluation of consumers' and producer's surpluses from water use and the capital cost of the dual (outdoor) system. The analysis is then extended to a dynamic approach where the water demand increases with time (as a result of a population increase) and where the dual system is allowed to expand. The model determines whether construction of a dual system represents a net benefit, and if so, what is the best time to initiate the system (corresponding to maximization of social welfare). Conditions under which an analytic solution is possible are discussed and results of an application are summarized (including sensitivity to different parameters). The analysis allows identification of key parameters influencing attractiveness of dual water systems.

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

Karpenko, V.; Salmon, J.

The goal of this project was to work together through the project phases to conceive, demonstrate, and produce concepts for detecting, locating, tracking, imaging, and assessing emissions passively or actively. The initial Sensor Concept Exploration Phase was postulated and assessed concepts at a first-order level to ascertain whether the parties’ concepts (either separately developed or jointly developed) had merit for missile defense and homeland security applications

The Characteristics of Religious Education Teachers and Respecting Diversity in Religious Education in Croatia

ERIC Educational Resources Information Center

Filipovic, Ana Thea; Rihtar, Stanko

2017-01-01

The first part of the article deals with the European and, specifically, Croatian sociopolitical and cultural framework of inclusive pedagogy and presents its basic postulates. The second part contains answers to questions linked to the treatment of differences in religious education in Croatia and characteristics of teachers that can be linked to…

Interpersonal Persuasion I: Formulation and First Test of a Rules-Based Theory.

ERIC Educational Resources Information Center

Lulofs, Roxane Salyer

A great deal of research has been done in the area of "compliance-message" tactics and strategies, but this research has not produced a coherent framework for studying this interpersonal communication process. Based on six axioms concerning the nature of communication behavior in general and on one postulate and five theorems defining…

Special Relativity in Week One: 2) All Clocks Run Slow

ERIC Educational Resources Information Center

Huggins, Elisha

2011-01-01

In our initial article on teaching special relativity in the first week of an introductory physics course, we used the principle of relativity and Maxwell's theory of light to derive Einstein's second postulate (that the speed of light is the same to all observers). In this paper we study thought experiments involving a light pulse clock moving…

Comprehension and Knowledge Components That Predict L2 Reading: A Latent-Trait Approach

ERIC Educational Resources Information Center

Yamashita, Junko; Shiotsu, Toshihiko

2017-01-01

Among predictors of second language (L2) reading, both first language (L1) reading and L2 listening embody the complexities of comprehension ability in their construct. Their contributions to L2 reading have rarely been examined together, probably because of the different theoretical frameworks in which they are postulated. Therefore, the field…

Integrative Analysis of Transgenic Alfalfa (Medicago sativa L.) Suggests New Metabolic Control Mechanisms for Monolignol Biosynthesis

PubMed Central

Lee, Yun; Chen, Fang; Gallego-Giraldo, Lina; Dixon, Richard A.; Voit, Eberhard O.

2011-01-01

The entanglement of lignin polymers with cellulose and hemicellulose in plant cell walls is a major biological barrier to the economically viable production of biofuels from woody biomass. Recent efforts of reducing this recalcitrance with transgenic techniques have been showing promise for ameliorating or even obviating the need for costly pretreatments that are otherwise required to remove lignin from cellulose and hemicelluloses. At the same time, genetic manipulations of lignin biosynthetic enzymes have sometimes yielded unforeseen consequences on lignin composition, thus raising the question of whether the current understanding of the pathway is indeed correct. To address this question systemically, we developed and applied a novel modeling approach that, instead of analyzing the pathway within a single target context, permits a comprehensive, simultaneous investigation of different datasets in wild type and transgenic plants. Specifically, the proposed approach combines static flux-based analysis with a Monte Carlo simulation in which very many randomly chosen sets of parameter values are evaluated against kinetic models of lignin biosynthesis in different stem internodes of wild type and lignin-modified alfalfa plants. In addition to four new postulates that address the reversibility of some key reactions, the modeling effort led to two novel postulates regarding the control of the lignin biosynthetic pathway. The first posits functionally independent pathways toward the synthesis of different lignin monomers, while the second postulate proposes a novel feedforward regulatory mechanism. Subsequent laboratory experiments have identified the signaling molecule salicylic acid as a potential mediator of the postulated control mechanism. Overall, the results demonstrate that mathematical modeling can be a valuable complement to conventional transgenic approaches and that it can provide biological insights that are otherwise difficult to obtain. PMID:21625579

Dual-Use system architecture for a space situational awareness system in Japan

NASA Astrophysics Data System (ADS)

Otani, Y.; Kohtake, N.; Ohkami, Y.

The use of outer space plays a vital role in both defense and civil fields. Since the separation of space activities between civil and defense applications is extremely inefficient, the Dual-Use concept has been considered fundamental for promoting the effective use of space. To the best of the authors' knowledge, most previous studies on Dual-Use focused on the technological aspects, and very few on a system engineering approach to Dual-Use. This left some important issues untouched such as the operational aspects of a system of systems, which need to be understood in a more generic context. This paper presents the results of a conceptual study, system design and management analysis of Dual-Use system architecture. First, an outline of the Dual-Use concept will be described and a definition of Dual-Use given. The effectiveness of applying the Dual-Use system concept to Space Situational Awareness (SSA) for both defense and civil users as a system of systems will then be discussed and investigated with a stakeholders analysis, context diagram and design structure matrix method. It has demonstrated that there is a need for a Dual-Use SSA Data Center which works as a binder between defense and civil systems as well as a data policy for constructing a Dual-Use SSA system.

Differential gene expression during thermal stress and bleaching in the Caribbean coral Montastraea faveolata.

PubMed

DeSalvo, M K; Voolstra, C R; Sunagawa, S; Schwarz, J A; Stillman, J H; Coffroth, M A; Szmant, A M; Medina, M

2008-09-01

The declining health of coral reefs worldwide is likely to intensify in response to continued anthropogenic disturbance from coastal development, pollution, and climate change. In response to these stresses, reef-building corals may exhibit bleaching, which marks the breakdown in symbiosis between coral and zooxanthellae. Mass coral bleaching due to elevated water temperature can devastate coral reefs on a large geographical scale. In order to understand the molecular and cellular basis of bleaching in corals, we have measured gene expression changes associated with thermal stress and bleaching using a complementary DNA microarray containing 1310 genes of the Caribbean coral Montastraea faveolata. In a first experiment, we identified differentially expressed genes by comparing experimentally bleached M. faveolata fragments to control non-heat-stressed fragments. In a second experiment, we identified differentially expressed genes during a time course experiment with four time points across 9 days. Results suggest that thermal stress and bleaching in M. faveolata affect the following processes: oxidative stress, Ca(2+) homeostasis, cytoskeletal organization, cell death, calcification, metabolism, protein synthesis, heat shock protein activity, and transposon activity. These results represent the first medium-scale transcriptomic study focused on revealing the cellular foundation of thermal stress-induced coral bleaching. We postulate that oxidative stress in thermal-stressed corals causes a disruption of Ca(2+) homeostasis, which in turn leads to cytoskeletal and cell adhesion changes, decreased calcification, and the initiation of cell death via apoptosis and necrosis.

Assessment of Dual-Antiplatelet Regimen for Pipeline Embolization Device Placement: A Survey of Major Academic Neurovascular Centers in the United States.

PubMed

Gupta, Raghav; Moore, Justin M; Griessenauer, Christoph J; Adeeb, Nimer; Patel, Apar S; Youn, Roy; Poliskey, Karen; Thomas, Ajith J; Ogilvy, Christopher S

2016-12-01

Flow diversion with the Pipeline Embolization Device (PED) currently is adopted for treatment of a variety of intracranial aneurysms. The elevated risk of thromboembolic complications associated with the device necessitates the need for administration of antiplatelet agents. We sought to assess current dual-antiplatelet therapy practices patterns and their associated costs after PED placement. An online questionnaire that assessed dual-antiplatelet regimens after flow diversion for treatment of intracranial aneurysms was developed and disseminated to 80 neurosurgeons at major academic cerebrovascular centers. Pricing information from 2 of the largest prescription payers in Massachusetts was used to calculate the monthly cost of these agents. Twenty-six responses (32.5%) were received. All respondents (100%) affirmed using clopidogrel and aspirin dual-antiplatelet therapy as a first-line regimen. Twenty-three (88.5%) routinely use platelet function testing. Eleven respondents (42.3%) each identified that they administer aspirin/ticagrelor and aspirin/prasugrel to clopidogrel hypo- or nonresponders. For uninsured patients, prasugrel was found to have the highest cumulative monthly cost ($471), followed by ticagrelor ($396), clopidogrel ($149), and ticlopidine ($110). Significant heterogeneity in dual-antiplatelet regimens after PED placement and associated costs exists at major academic neurovascular centers. The most commonly used first-line dual-antiplatelet regimen consists of aspirin and clopidogrel. Two major alternate protocols involving ticagrelor and prasugrel are administered to clopidogrel hyporesponders. The optimal dual-antiplatelet regimen for patients with cerebrovascular conditions has not been established, given limited prospective data within the neurointerventional literature. Copyright © 2016 Elsevier Inc. All rights reserved.

Enhanced dual-frequency operation of a polymerized liquid crystal microplate by liquid crystal infiltration

NASA Astrophysics Data System (ADS)

Kumagai, Takayuki; Yoshida, Hiroyuki; Ozaki, Masanori

2017-04-01

The electric-field-induced switching behavior of a polymer microplate is investigated. A microplate fabricated with a photopolymerizable dual-frequency liquid crystal was surrounded by an unpolymerized photopolymerizable dual-frequency liquid crystal in the isotropic phase. As an electric field was applied along the plane of the microplate, the microplate switched to set its interior molecular orientation to be either parallel or perpendicular to the field, depending on the frequency. Analysis of the rotational behavior, as well as numerical calculations, showed that the surrounding unpolymerized photopolymerizable dual-frequency liquid crystal infiltrated into the microplate, which enhanced the dielectric properties of the microplate. To the best of our knowledge, this is the first report of an enhanced dual-frequency dielectric response of a polymer microplate induced by liquid crystal infiltration.

Tunable and switchable dual-wavelength dissipative soliton generation in an all-normal-dispersion Yb-doped fiber laser with birefringence fiber filter.

PubMed

Zhang, Z X; Xu, Z W; Zhang, L

2012-11-19

We report the generation of tunable single- and dual-wavelength dissipative solitons in an all-normal-dispersion mode-locked Yb-doped fiber laser, to the best of our knowledge, for the first time. Besides single-wavelength mode-locking, dual-wavelength mode-locking was achieved using an in-line birefringence fiber filter with periodic multiple passbands, which not only allows multiple wavelengths to oscillate simultaneously but also performs spectrum modulation on highly chirped dissipative pulse. Furthermore, taking advantage of the tunability of the birefringence fiber filter, wavelength tuning for both single- and dual-wavelength dissipative soliton mode-locking was realized. The dual-wavelength operation is also switchable. The all-fiber dissipative laser with flexible outputs can meet diverse application needs.

Feasibility of an on-line fission-gas-leak detection system

NASA Technical Reports Server (NTRS)

Lustig, P. H.

1973-01-01

Calculations were made to determine if a cladding failure could be detected in a 100-kW zirconium hydride reactor primary system by monitoring the highly radioactive NaK coolant for the presence of I-131. The system is to be completely sealed. A leak of 0.01 percent from a single fuel pin was postulated. The 0.364-MeV gamma of I-131 could be monitored on an almost continuous basis, while its presence could be varified by using a longer counting time for the 0.638-MeV gamma. A lithium-drifted germanium detector would eliminate radioactive corrosion product interference that could occur with a sodium iodide scintillation detector.

Structural analysis of color video camera installation on tank 241AW101 (2 Volumes)

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

Strehlow, J.P.

1994-08-24

A video camera is planned to be installed on the radioactive storage tank 241AW101 at the DOE` s Hanford Site in Richland, Washington. The camera will occupy the 20 inch port of the Multiport Flange riser which is to be installed on riser 5B of the 241AW101 (3,5,10). The objective of the project reported herein was to perform a seismic analysis and evaluation of the structural components of the camera for a postulated Design Basis Earthquake (DBE) per the reference Structural Design Specification (SDS) document (6). The detail of supporting engineering calculations is documented in URS/Blume Calculation No. 66481-01-CA-03 (1).

Measurements of Sheath Currents and Equilibrium Potential on the Explorer VIII Satellite (1960 xi)

NASA Technical Reports Server (NTRS)

Bourdeau, R. E.; Donley, J. L.; Serbu, G. P.; Whipple, E. C., Jr.

1961-01-01

Experimental data were obtained from the Explorer VIII satellite on five parameters pertinent to the problem of the interaction of space vehicles with an ionized atmosphere. The five parameters are: photoemission current due to electrons emitted from the satellite surfaces as a result of solar radiation; electron and positive ion currents due to the diffusion of charged particles from the medium to the spacecraft; the vehicle potential relative to the medium, and the ambient electron temperature. Included in the experimental data is the aspect dependence of the photoemission and diffusion currents. On the basis of the observations, certain characteristics of the satellite's plasma sheath are postulated.

Precision Dentistry in Early Childhood: The Central Role of Genomics.

PubMed

Divaris, Kimon

2017-07-01

Pediatric oral health is determined by the interaction of environmental factors and genetic influences. This is the case for early childhood caries, the most common disease of childhood. The complexity of exogenous-environmental factors interacting with innate biological predispositions results in a continuum of normal variation, as well as oral health and disease outcomes. Optimal oral health and care or precision dentistry warrants comprehensive understanding of these influences and tools enabling intervention on modifiable factors. This article reviews the current knowledge of the genomic basis of pediatric oral health and highlights known and postulated mechanistic pathways of action relevant to early childhood caries. Copyright © 2017 Elsevier Inc. All rights reserved.

The biosynthesis of 4-hydroxycoumarin and dicoumarol by Aspergillus fumigatus Fresenius.

PubMed

Bye, A; King, H K

1970-04-01

A strain of Aspergillus fumigatus Fresenius, isolated from spoiled hay, converts melilotic acid (o-hydroxyphenylpropionic acid) and o-coumaric acid into 4-hydroxycoumarin and dicoumarol. The sequence is shown to be melilotic acid (I) [Formula: see text] coumaric acid (IV) [Formula: see text] beta-hydroxymelilotic acid (II) [Formula: see text] beta-oxomelilotic acid (III) [Formula: see text] 4-hydroxycoumarin (VI), on the basis of (1) studies on the formation of postulated intermediates, (2) experiments with isotopically labelled materials and (3) sequential enzyme induction. In the presence of semicarbazide, o-coumaraldehyde is formed from o-coumaric acid: there is no evidence, however, that this lies on the normal metabolic pathway.

LEAD AND MERCURY EACH AS PRIME MATTER IN ALCHEMY

PubMed Central

Mahdihassan, S.

1988-01-01

Prime Matter is matter-cum-energy. The first substance identified as such was lead. When gently heated it becomes red and redness means soul or energy so that lead was potentially red or soul-like and as such dual natured. Mercury also becomes red and can return to white metal. It was thus dual natured and was the second substance recognized as Prime Matter. First lead alone and then lead and mercury were considered as the source of all metals. PMID:22557603

Humanity's Dual Response to Dogs and Wolves.

PubMed

Treves, Adrian; Bonacic, Cristian

2016-07-01

Dogs were first domesticated 31 000-41 000 years ago. Humanity has experienced ecological costs and benefits from interactions with dogs and wolves. We propose that humans inherited a dual response of attraction or aversion that expresses itself independently to domestic and wild canids. The dual response has had far-reaching consequences for the ecology and evolution of all three taxa, including today's global 'ecological paw print' of 1 billion dogs and recent eradications of wolves. Copyright © 2016 Elsevier Ltd. All rights reserved.

Composite membranes, methods of making same, and applications of same

DOEpatents

Pintauro, Peter N.; Park, Andrew; Ballengee, Jason

2016-05-24

In one aspect of the present invention, a method of fabricating a composite membrane includes: forming a first polymer solution from a first polymer and a second polymer solution from a second polymer, respectively, where the first polymer includes a charged polymer and the second polymer includes an uncharged polymer; electrospinning, separately and simultaneously, the first and second polymer solutions to form a dual fiber mat with first polymer fibers and second polymer fibers; and processing the dual fiber mat by softening and flowing one of the first or second polymer fibers to fill in the void space between the other of the first and second polymer fibers so as to form the composite membrane. In some embodiments, the composite membrane may be a proton exchange membrane (PEM) or an anion exchange membrane (AEM).

[Margaret Cavendish vs Robert Hooke: An impossible duel].

PubMed

Aït-Touati, Frédérique

2016-12-01

In 1665, Robert Hooke published his major work in microscopy, Micrographia, a defense of experimental philosophy. The following year, Margaret Cavendish, Duchess of Newcastle, published at her own expense a treatise and a novel that undermined the basis of this new science. The dispute broke out at the initiative of the Duchess, in the context of a vast controversy about the legitimacy and the efficiency of optical instruments in natural philosophy. All the figures of the dual are used, except one: the counterattack. Cavendish, indeed, was alone on the battlefield. Is it possible to call a dual a battle with only one combatant? This particular case of dispute that stops owing to the shortage of combatants is the subject of this article.

A novel method for flow pattern identification in unstable operational conditions using gamma ray and radial basis function.

PubMed

Roshani, G H; Nazemi, E; Roshani, M M

2017-05-01

Changes of fluid properties (especially density) strongly affect the performance of radiation-based multiphase flow meter and could cause error in recognizing the flow pattern and determining void fraction. In this work, we proposed a methodology based on combination of multi-beam gamma ray attenuation and dual modality densitometry techniques using RBF neural network in order to recognize the flow regime and determine the void fraction in gas-liquid two phase flows independent of the liquid phase changes. The proposed system is consisted of one 137 Cs source, two transmission detectors and one scattering detector. The registered counts in two transmission detectors were used as the inputs of one primary Radial Basis Function (RBF) neural network for recognizing the flow regime independent of liquid phase density. Then, after flow regime identification, three RBF neural networks were utilized for determining the void fraction independent of liquid phase density. Registered count in scattering detector and first transmission detector were used as the inputs of these three RBF neural networks. Using this simple methodology, all the flow patterns were correctly recognized and the void fraction was predicted independent of liquid phase density with mean relative error (MRE) of less than 3.28%. Copyright © 2017 Elsevier Ltd. All rights reserved.

Photochemical Dual-Catalytic Synthesis of Alkynyl Sulfides.

PubMed

Santandrea, Jeffrey; Minozzi, Clémentine; Cruché, Corentin; Collins, Shawn K

2017-09-25

A photochemical dual-catalytic cross-coupling to form alkynyl sulfides via C(sp)-S bond formation is described. The cross-coupling of thiols and bromoalkynes is promoted by a soluble organic carbazole-based photocatalyst using continuous flow techniques. Synthesis of alkynyl sulfides bearing a wide range of electronically and sterically diverse aromatic alkynes and thiols can be achieved in good to excellent yields (50-96 %). The simple continuous flow setup also allows for short reaction times (30 min) and high reproducibility on gram scale. In addition, we report the first application of photoredox/nickel dual catalysis towards macrocyclization, as well as the first example of the incorporation of an alkynyl sulfide functional group into a macrocyclic scaffold. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Student Participation in Dual Enrollment and College Success

ERIC Educational Resources Information Center

Jones, Stephanie J.

2014-01-01

The study investigated the impact of dual enrollment participation on the academic preparation of first-year full-time college students at a large comprehensive community college and a large research university. The research design was causal-comparative and utilized descriptive and inferential statistics. Multivariate analysis of variances were…

Giftedness and ADHD: Identification, Misdiagnosis, and Dual Diagnosis

ERIC Educational Resources Information Center

Mullet, Dianna R.; Rinn, Anne N.

2015-01-01

Many gifted characteristics overlap the symptoms of attention deficity-hyperactivity disorder (ADHD). The potential for the misdiagnosis of giftedness as ADHD exists, but so does the potential for a dual diagnosis of giftedness and ADHD. A decade after the misdiagnosis of giftedness as ADHD was first investigated we examine lessons learned…

Diversity of free-living amoebae in a dual distribution (potable and recycled) water system

EPA Science Inventory

Free-living amoebae are known to facilitate the growth of water associated pathogens. This study, for the first time, explored the diversity of free-living amoebae in a dual distribution (potable and recycled) water system in Rouse Hill NSW, Australia. Water and biofilm samples w...

Individual Differences in Dual Task Performance. Final Report.

ERIC Educational Resources Information Center

Lansman, Marcy; Hunt, Earl

This report summarizes the research results and provides a reference. The basic question addressed was, "Is performance on multi-component tasks predicted by performance on the individual components performed separately?" In the first series of experiments, a dual task involving memory and verbal processing components to predict a…

Isolating the Neural Mechanisms of Interference During Continuous Multisensory Dual-task Performance

DTIC Science & Technology

2014-01-01

sion accuracy in each task, the signal detection theory sensitivity measure of d0 was used (Macmillan & Creelman , 1991; Green & Swets, 1966). First...J. (1998). Sources of dual-task interference: Evidence from human electrophysiology. Psychological Science, 9, 223–227. Macmillan, N. A., & Creelman

Selective impairment of masked priming in dual-task performance.

PubMed

Fischer, Rico; Kiesel, Andrea; Kunde, Wilfried; Schubert, Torsten

2011-03-01

This study investigated the impact of divided attention on masked priming. In a dual-task setting, two tasks had to be carried out in close temporal succession: a tone discrimination task and a masked priming task. The order of the tasks was varied between experiments, and attention was always allocated to the first task-that is, the first task was prioritized. The priming task was the second (nonprioritized) task in Experiment 1 and the first (prioritized) task in Experiment 2. In both experiments, "novel" prime stimuli associated with semantic processing were essentially ineffective. However, there was intact priming by another type of prime stimuli associated with response priming. Experiment 3 showed that all these prime stimuli can reveal significant priming effects during a task-switching paradigm in which both tasks were performed consecutively. We conclude that dual-task specific interference processes (e.g., the simultaneous coordination of multiple stimulus-response rules) selectively impair priming that is assumed to rely on semantic processing.

A single VLSI chip for computing syndromes in the (225, 223) Reed-Solomon decoder

NASA Technical Reports Server (NTRS)

Hsu, I. S.; Truong, T. K.; Shao, H. M.; Deutsch, L. J.

1986-01-01

A description of a single VLSI chip for computing syndromes in the (255, 223) Reed-Solomon decoder is presented. The architecture that leads to this single VLSI chip design makes use of the dual basis multiplication algorithm. The same architecture can be applied to design VLSI chips to compute various kinds of number theoretic transforms.

Strategic Mobility 21 Technical Plan

DTIC Science & Technology

2006-09-06

or grant. b. Technical documents with this statement may be made available or sold to the public and foreign nationals, companies, and governments ...including adversary governments , and may be exported. c. This statement may not be used on technical documents that formerly were classified...Transportation Technologies (CCDOTT), a government -industry academic collaborative enterprise. 2 Dual-use technology serves as a basis for both

Higher Educational Cost-Sharing, Dual-Track Tuition Fees, and Higher Educational Access: The East African Experience

ERIC Educational Resources Information Center

Marcucci, Pamela; Johnstone, D. Bruce; Ngolovoi, Mary

2008-01-01

Three universal demands characterize higher education globally: the demand for higher quality, for increased access, and for greater equity. In East Africa, where resources are highly constrained, no nation has been able to meet these demands on the basis of public expenditures alone. Instead countries have had to increase resources from nonpublic…

Genetic algorithm based feature selection combined with dual classification for the automated detection of proliferative diabetic retinopathy.

PubMed

Welikala, R A; Fraz, M M; Dehmeshki, J; Hoppe, A; Tah, V; Mann, S; Williamson, T H; Barman, S A

2015-07-01

Proliferative diabetic retinopathy (PDR) is a condition that carries a high risk of severe visual impairment. The hallmark of PDR is the growth of abnormal new vessels. In this paper, an automated method for the detection of new vessels from retinal images is presented. This method is based on a dual classification approach. Two vessel segmentation approaches are applied to create two separate binary vessel map which each hold vital information. Local morphology features are measured from each binary vessel map to produce two separate 4-D feature vectors. Independent classification is performed for each feature vector using a support vector machine (SVM) classifier. The system then combines these individual outcomes to produce a final decision. This is followed by the creation of additional features to generate 21-D feature vectors, which feed into a genetic algorithm based feature selection approach with the objective of finding feature subsets that improve the performance of the classification. Sensitivity and specificity results using a dataset of 60 images are 0.9138 and 0.9600, respectively, on a per patch basis and 1.000 and 0.975, respectively, on a per image basis. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mind wandering in text comprehension under dual-task conditions.

PubMed

Dixon, Peter; Li, Henry

2013-01-01

In two experiments, subjects responded to on-task probes while reading under dual-task conditions. The secondary task was to monitor the text for occurrences of the letter e. In Experiment 1, reading comprehension was assessed with a multiple-choice recognition test; in Experiment 2, subjects recalled the text. In both experiments, the secondary task replicated the well-known "missing-letter effect" in which detection of e's was less effective for function words and the word "the." Letter detection was also more effective when subjects were on task, but this effect did not interact with the missing-letter effect. Comprehension was assessed in both the dual-task conditions and in control single-task conditions. In the single-task conditions, both recognition (Experiment 1) and recall (Experiment 2) was better when subjects were on task, replicating previous research on mind wandering. Surprisingly, though, comprehension under dual-task conditions only showed an effect of being on task when measured with recall; there was no effect on recognition performance. Our interpretation of this pattern of results is that subjects generate responses to on-task probes on the basis of a retrospective assessment of the contents of working memory. Further, we argue that under dual-task conditions, the contents of working memory is not closely related to the reading processes required for accurate recognition performance. These conclusions have implications for models of text comprehension and for the interpretation of on-task probe responses.

Mind wandering in text comprehension under dual-task conditions

PubMed Central

Dixon, Peter; Li, Henry

2013-01-01

In two experiments, subjects responded to on-task probes while reading under dual-task conditions. The secondary task was to monitor the text for occurrences of the letter e. In Experiment 1, reading comprehension was assessed with a multiple-choice recognition test; in Experiment 2, subjects recalled the text. In both experiments, the secondary task replicated the well-known “missing-letter effect” in which detection of e's was less effective for function words and the word “the.” Letter detection was also more effective when subjects were on task, but this effect did not interact with the missing-letter effect. Comprehension was assessed in both the dual-task conditions and in control single-task conditions. In the single-task conditions, both recognition (Experiment 1) and recall (Experiment 2) was better when subjects were on task, replicating previous research on mind wandering. Surprisingly, though, comprehension under dual-task conditions only showed an effect of being on task when measured with recall; there was no effect on recognition performance. Our interpretation of this pattern of results is that subjects generate responses to on-task probes on the basis of a retrospective assessment of the contents of working memory. Further, we argue that under dual-task conditions, the contents of working memory is not closely related to the reading processes required for accurate recognition performance. These conclusions have implications for models of text comprehension and for the interpretation of on-task probe responses. PMID:24101909

A new method for designing dual foil electron beam forming systems. I. Introduction, concept of the method

NASA Astrophysics Data System (ADS)

Adrich, Przemysław

2016-05-01

In Part I of this work existing methods and problems in dual foil electron beam forming system design are presented. On this basis, a new method of designing these systems is introduced. The motivation behind this work is to eliminate the shortcomings of the existing design methods and improve overall efficiency of the dual foil design process. The existing methods are based on approximate analytical models applied in an unrealistically simplified geometry. Designing a dual foil system with these methods is a rather labor intensive task as corrections to account for the effects not included in the analytical models have to be calculated separately and accounted for in an iterative procedure. To eliminate these drawbacks, the new design method is based entirely on Monte Carlo modeling in a realistic geometry and using physics models that include all relevant processes. In our approach, an optimal configuration of the dual foil system is found by means of a systematic, automatized scan of the system performance in function of parameters of the foils. The new method, while being computationally intensive, minimizes the involvement of the designer and considerably shortens the overall design time. The results are of high quality as all the relevant physics and geometry details are naturally accounted for. To demonstrate the feasibility of practical implementation of the new method, specialized software tools were developed and applied to solve a real life design problem, as described in Part II of this work.

1958 NASA/USAF Space Probes (ABLE-1). Volume 3; Vehicles, Trajectories, and Flight Histories

NASA Technical Reports Server (NTRS)

1959-01-01

The three NASA/USAF lunar probes of August 17, October 13, and November 8, 1958 are described. Details of the program, the vehicles, the payloads, the firings, the tracking, and the results are presented. Principal result was the first experimental verification of a confined radiation zone of the type postulated by Van Allen and others.

Special Relativity in Week One: 3) Introducing the Lorentz Contraction

ERIC Educational Resources Information Center

Huggins, Elisha

2011-01-01

This is the third of four articles on teaching special relativity in the first week of an introductory physics course. With Einstein's second postulate that the speed of light is the same to all observers, we could use the light pulse clock to introduce time dilation. But we had difficulty introducing the Lorentz contraction until we saw the movie…

Excitement or Anxiety? A Case Study of Indian Postgraduate Sojourners at University of Nottingham

ERIC Educational Resources Information Center

Unjore, Sanju

2014-01-01

Moving to a new country is often seen as a disturbing event in sojourners' lives. Several models of adjustment postulate that the first phase of the sojourn is either categorised by euphoria or anxiety. Using a case study of three Indian Postgraduate students, this paper investigates whether the beginning phase of these sojourners was euphoric or…

Do Cs Make Degrees? The Relationship of Maximizing versus Satisficing Student Types and Academic Success in the Business Curriculum

ERIC Educational Resources Information Center

Stohs, Mark Hoven

2016-01-01

The author analyzed the academic performance of 197 business students in their first required finance course. He postulated that the students' performance related to whether their academic strategy was one of two types: satisficing or maximizing. Satisficers seemed content with getting Cs to earn their degree, while maximizers aimed for the…

Constructive Development of the Solutions of Linear Equations in Introductory Ordinary Differential Equations

ERIC Educational Resources Information Center

Mallet, D. G.; McCue, S. W.

2009-01-01

The solution of linear ordinary differential equations (ODEs) is commonly taught in first-year undergraduate mathematics classrooms, but the understanding of the concept of a solution is not always grasped by students until much later. Recognizing what it is to be a solution of a linear ODE and how to postulate such solutions, without resorting to…

Derivation of the Schrodinger Equation from the Hamilton-Jacobi Equation in Feynman's Path Integral Formulation of Quantum Mechanics

ERIC Educational Resources Information Center

Field, J. H.

2011-01-01

It is shown how the time-dependent Schrodinger equation may be simply derived from the dynamical postulate of Feynman's path integral formulation of quantum mechanics and the Hamilton-Jacobi equation of classical mechanics. Schrodinger's own published derivations of quantum wave equations, the first of which was also based on the Hamilton-Jacobi…

College Persistence of First-Year African American and African Immigrant Males: Differences of Non-Academic and Other Factors on Community College Black Male Students

ERIC Educational Resources Information Center

Adams-Mahaley, Charlene

2012-01-01

Literature has postulated that noncognitive or psychosocial variables are a strong predictor of African American and international students persisting in college. Using a modified version of the Noncognitive-Revised (NCQ-R) questionnaire developed by Tracey and Sedlacek (1984), this mixed methods descriptive study investigated the relationships…

Lasiodiplodia theobromae is a Mycoparasite of a Powdery Mildew Pathogen

PubMed Central

Singh, Leena

2009-01-01

Powdery mildews on over 40 plants in Bangalore were screened during July-December of 2003~2008. Isolates from mycoparasitised Oidium caesalpiniacearum of Bauhinia purpurea comprised Lasiodiplodia theobromae, in addition to Ampelomyces quisqualis. Koch's postulates were satisfied to establish the mycoparasitism of L. theobromae. This is the first report that L. theobromae acts as a mycoparasite of a powdery mildew. PMID:23983554

Conditions That Promote the Academic Performance of College Students in a Remedial Mathematics Course: Academic Competence, Academic Resilience, and the Learning Environment

ERIC Educational Resources Information Center

Foshee, Cecile Mary

2013-01-01

Researchers have postulated that math academic achievement increases student success in college (Lee, 2012; Silverman & Seidman, 2011; Vigdor, 2013), yet 80% of universities and 98% of community colleges require many of their first-year students to be placed in remedial courses (Bettinger & Long, 2009). Many high school graduates are…

Dense matter theory: A simple classical approach

NASA Astrophysics Data System (ADS)

Savić, P.; Čelebonović, V.

1994-07-01

In the sixties, the first author and by P. Savić and R. Kašanin started developing a mean-field theory of dense matter. It is based on the Coulomb interaction, supplemented by a microscopic selection rule and a set of experimentally founded postulates. Applications of the theory range from the calculation of models of planetary internal structure to DAC experiments.

Nitrogen saturation in a high elevation New England spruce-fir stand

Treesearch

Steven G. McNulty; John D. Aber; Steven D. Newman

1994-01-01

High rates of nitrogen (N) deposition were first postulated as a cause of N saturation (i.e. the availability of NH-N and NO3-N in excess of total combined plant and microbial nutritional demand) and spruce mortality during the1980s. To test this hypothesis, N addition plots were established in 1988, in a high elevation...

The role of solid state 13 C NMR spectroscopy in studies of the nature of native celluloses

Treesearch

R.H. Atalla; D.L. VanderHart

1999-01-01

Published spectroscopic observations pertaining to the crystal structure of native celluloses are reviewed for the purpose of defining our current level of understanding about crystalline polymorphism in these materials. Emphasis is placed on observations from solid state 13 C nuclear magnetic resonance (NMR), which first led to the postulate that most native,...

Casimer Funk, nonconformist nomenclature, and networks surrounding the discovery of vitamins.

PubMed

Maltz, Alesia

2013-07-01

In the 2 decades between when the existence of vitamins was first postulated and when they were isolated, scientists and research physicians could produce no conclusive evidence for their existence from the laboratory or clinic. By the time the first vitamin was chemically isolated, vitamins were already widely accepted by scientists, clinicians, the public, and government agencies. In the period between when vitamins were postulated and the Nobel Prize was awarded for their discovery, a debate over nomenclature served as a substitute for a priority dispute. The most popular term "vitamine" was introduced by Casimer Funk in 1912 and was changed to "vitamin" by Cecil Drummond in 1920. Initial conditions surrounding the discovery of vitamins, including World War I, necessitated the creation of unusual networks for the dissemination of scientific information about vitamins. In Great Britain, research institutes, government agencies, and individual researchers were instrumental in creating a set of national and international networks for the dissemination of information from research laboratories to hospitals, physicians, pharmaceutical houses, and the public. These networks of dissemination still exert an influence on how scientific information about vitamins is communicated to the public today.

Conventional armed forces in Europe: Technology scenario development

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

Houser, G.M.

1990-07-01

In January 1986, the Soviet Union's Mikhail Gorbachev proposed elimination of all nuclear weapons by the year 2000. In April of that year, Mr. Gorbachev proposed substantial reductions of conventional weapons in Europe, from the Atlantic Ocean to the Ural Mountains, including reductions in operational-tactical nuclear weapons. In May 1986, the North Atlantic Treaty Organization (NATO) responded with the Brussels Declaration on Conventional Arms Control,'' which indicated readiness to open East/West discussions on establishing a mandate for negotiating conventional arms control throughout Europe. The Group of 23,'' which met in Vienna beginning in February 1987, concluded the meeting in Januarymore » 1989 with a mandate for the Conventional Armed Forced in Europe (CFE) negotiations. On 6 March 1989, CFE talks began, and these talks have continued through six rounds (as of April 1990). Although US President George Bush, on 30 May 1989, called for agreement within six months to a year, and the Malta meeting of December 1989 called for completion of a CFE agreement by the end of 1990, much remains to be negotiated. This report provides three types of information. First, treaty provisions brought to the table by both sides are compared. Second, on the basis of these provisions, problem areas for each of the provision elements are postulated and possible scenarios for resolving these problem areas are developed. Third, the scenarios are used as requirements for tasks assigned program elements for possible US implementation of a CFE treaty. As progress is achieved during the negotiations, this report could be updated, as necessary, in each of the areas to provide a continuing systematic basis for program implementation and technology development. 8 refs.« less

Testosterone and Erectile Function: From Basic Research to a New Clinical Paradigm for Managing Men with Androgen Insufficiency and Erectile Dysfunction

PubMed Central

Traish, Abdulmaged M.; Goldstein, Irwin; Kim, Noel N.

2007-01-01

Objectives Androgens are essential for the development and growth of the penis, and they regulate erectile physiology by multiple mechanisms. Our goal is to provide a concise overview of the basic research and how this knowledge can be translated into a new clinical paradigm for patient management. In addition, this new paradigm may serve as a basis for stimulating constructive debate regarding the use of testosterone in men, and to promote new, innovative basic and clinical research to further understand the underlying mechanisms of androgen action in restoring erectile physiology. Methods A literature review was performed utilizing the US National Library of Medicine's PubMed database. Results On the basis of evidence derived from laboratory animal studies and clinical data, we postulate that androgen insufficiency disrupts cellular-signaling pathways and produces pathologic alterations in penile tissues, leading to erectile dysfunction. In this review, we discuss androgen-dependent cellular, molecular, and physiologic mechanisms modulating erectile function in the animal model, and the implication of this knowledge in testosterone use in the clinical setting to treat erectile dysfunction. The new clinical paradigm incorporates many of the consensed points of view discussed in traditional consensed algorithms exclusively designed for men with androgen insufficiency. There are, however, novel and innovative differences with this new clinical paradigm. This paradigm represents a fresh effort to provide mandatory and optional management strategies for men with both androgen insufficiency and erectile dysfunction. Conclusions The new clinical paradigm is evidence-based and represents one of the first attempts to address a logical management plan for men with concomitant hormonal and sexual health concerns. PMID:17329016

Transferability of Dual-Task Coordination Skills after Practice with Changing Component Tasks

PubMed Central

Schubert, Torsten; Liepelt, Roman; Kübler, Sebastian; Strobach, Tilo

2017-01-01

Recent research has demonstrated that dual-task performance with two simultaneously presented tasks can be substantially improved as a result of practice. Among other mechanisms, theories of dual-task practice-relate this improvement to the acquisition of task coordination skills. These skills are assumed (1) to result from dual-task practice, but not from single-task practice, and (2) to be independent from the specific stimulus and response mappings during the practice situation and, therefore, transferable to new dual task situations. The present study is the first that provides an elaborated test of these assumptions in a context with well-controllable practice and transfer situations. To this end, we compared the effects of dual-task and single-task practice with a visual and an auditory sensory-motor component task on the dual-task performance in a subsequent transfer session. Importantly, stimulus and stimulus-response mapping conditions in the two component tasks changed repeatedly during practice sessions, which prevents that automatized stimulus-response associations may be transferred from practice to transfer. Dual-task performance was found to be improved after practice with the dual tasks in contrast to the single-task practice. These findings are consistent with the assumption that coordination skills had been acquired, which can be transferred to other dual-task situations independently on the specific stimulus and response mapping conditions of the practiced component tasks. PMID:28659844

Glucose Starvation Alters Heat Shock Response, Leading to Death of Wild Type Cells and Survival of MAP Kinase Signaling Mutant

PubMed Central

Higgins, LeeAnn; Markowski, Todd; Brambl, Robert

2016-01-01

A moderate heat shock induces Neurospora crassa to synthesize large quantities of heat shock proteins that are protective against higher, otherwise lethal temperatures. However, wild type cells do not survive when carbohydrate deprivation is added to heat shock. In contrast, a mutant strain defective in a stress-activated protein kinase does survive the combined stresses. In order to understand the basis for this difference in survival, we have determined the relative levels of detected proteins in the mutant and wild type strain during dual stress, and we have identified gene transcripts in both strains whose quantities change in response to heat shock or dual stress. These data and supportive experimental evidence point to reasons for survival of the mutant strain. By using alternative respiratory mechanisms, these cells experience less of the oxidative stress that proves damaging to wild type cells. Of central importance, mutant cells recycle limited resources during dual stress by undergoing autophagy, a process that we find utilized by both wild type and mutant cells during heat shock. Evidence points to inappropriate activation of TORC1, the central metabolic regulator, in wild type cells during dual stress, based upon behavior of an additional signaling mutant and inhibitor studies. PMID:27870869

Structural and energetic basis for the molecular recognition of dual synthetic vs. natural inhibitors of EGFR/HER2.

PubMed

Bello, Martiniano; Saldaña-Rivero, Lucia; Correa-Basurto, José; García, Benjamín; Sánchez-Espinosa, Victor Armando

2018-05-01

Activation of EGFR starts by ligand binding at the extracellular domain which results in homo and heterodimerization, leading to phosphorylation, activation of downstream signaling pathways which upregulate expression of genes, proliferation and angiogenesis. Abnormalities in the expression of EGFR play a critical role in the development of different types of cancer. HER2 is the preferred heterodimerization partner for EGFR; this biological characteristic together with the high percentage of structural homology has been exploited in the design of dual synthetic inhibitors against EGFR/HER2. Herein we combined structural data and molecular dynamics (MD) simulations coupled to an MMGBSA approach to provide insight into the binding mechanism between two dual synthetics (lapatinib and TAK-285) and one dual natural inhibitor (EGCG) which target EGFR/HER2. In addition, we proposed some EGCG derivatives which were filtered through in silico screening. Structural analysis demonstrated that the coupling of synthetic, natural or newly designed compounds impacts the conformational space of EGFR and HER2 differently. Energetic analysis points out that lapatinib and TAK-285 have better affinity for inactive EGFR than the active EGFR state or HER2, whereas some EGCG derivatives seem to form binding affinities similar to those observed for lapatinib or TAK-285. Copyright © 2018 Elsevier B.V. All rights reserved.

First Observations with the New Dual Sphere Superconducting Gravimeter Osg-073 at Metsähovi, Finland

NASA Astrophysics Data System (ADS)

Virtanen, H.; Raja-Halli, A.; Bilker-Koivula, M.; Naranen, J.; Ruotsalainen, H. E. O.

2014-12-01

The new dual sphere superconducting gravimeter (SG) OSG-073 was installed in the Metsähovi Geodetic Observatory in February 2014. Its two gravity sensors are side by side, not one on top of another as in most earlier dual sensor installations. One sensor is the standard iGrav™ SG, with a lightweight sphere (5 grams) which is nearly drift-free. The second sensor uses a heavy 20-gram sphere which gives ultra low noise and a much higher quality factor Q. We present time domain observations of the first months, and estimate drift rates after the initial exponential drift. We have determined the transfer functions. Calibration factors were obtained using parallel registrations with the FG5X-221 absolute gravimeter of the FGI. We show selected free oscillation spectra from the SG, and seismic data obtained at Metsähovi with the Nanometrics Trillium 120P broadband seismometer of the Institute of Seismology (University of Helsinki). The noise level of the data is then compared with the New Low Noise Model NLNM. The results with the dual sphere SG can be compared with parallel observations with the SG T020. This 20-year old instrument is situated in the same room at a distance of 2 metres from the dual-sphere SG.

Covariance in self-dual inhomogeneous models of effective quantum geometry: Spherical symmetry and Gowdy systems

NASA Astrophysics Data System (ADS)

Ben Achour, Jibril; Brahma, Suddhasattwa

2018-06-01

When applying the techniques of loop quantum gravity (LQG) to symmetry-reduced gravitational systems, one first regularizes the scalar constraint using holonomy corrections, prior to quantization. In inhomogeneous system, where a residual spatial diffeomorphism symmetry survives, such modification of the gauge generator generating time reparametrization can potentially lead to deformations or anomalies in the modified algebra of first-class constraints. When working with self-dual variables, it has already been shown that, for spherically symmetric geometry coupled to a scalar field, the holonomy-modified constraints do not generate any modifications to general covariance, as one faces in the real variables formulation, and can thus accommodate local degrees of freedom in such inhomogeneous models. In this paper, we extend this result to Gowdy cosmologies in the self-dual Ashtekar formulation. Furthermore, we show that the introduction of a μ ¯-scheme in midisuperspace models, as is required in the "improved dynamics" of LQG, is possible in the self-dual formalism while being out of reach in the current effective models using real-valued Ashtekar-Barbero variables. Our results indicate the advantages of using the self-dual variables to obtain a covariant loop regularization prior to quantization in inhomogeneous symmetry-reduced polymer models, additionally implementing the crucial μ ¯-scheme, and thus a consistent semiclassical limit.

Dual doped monolayer and bilayer graphene: The case of 4p and 2p elements

NASA Astrophysics Data System (ADS)

Denis, Pablo A.; Iribarne, Federico

2016-08-01

4p/2p dual-doped monolayer and bilayer graphene were studied via first principle calculations. Generally, dopants prefer to be agglomerated. A second dopant significantly reduces formation energies. Thus, partially reduced graphene oxide would favor substitutional doping by facilitating the introduction of the 4p dopants. Dual-doping can tune the band gap from 0.1 to 0.8 eV. For bilayer graphene, large atomic radii elements (Gallium and Germanium) form interlayer bonds with the undoped sheet. For some dual-doped graphenes, interlayer GaC and GeC bonds were formed, increasing the chemical reactivity of the undoped layer and affecting its electronic structure, with metallic or semiconducting characters observed.

Dual diagnosis capability in mental health and addiction treatment services: An assessment of programs across multiple state systems

PubMed Central

McGovern, Mark P.; Lambert-Harris, Chantal; Gotham, Heather J.; Claus, Ronald E.; Xie, Haiyi

2012-01-01

Despite increased awareness of the benefits of integrated services for persons with co-occurring substance use and psychiatric disorders, estimates of the availability of integrated services vary widely. The present study utilized standardized measures of program capacity to address co-occurring disorders, the Dual Diagnosis Capability in Addiction Treatment (DDCAT) and Dual Diagnosis Capability in Mental Health Treatment (DDCMHT) indexes, and sampled 256 programs across the United States. Approximately 18% of addiction treatment and 9% of mental health programs met criteria for dual diagnosis capable services. This is the first report on public access to integrated services using objective measures. PMID:23183873

Microstructural Developments Leading to New Advanced High Strength Sheet Steels: A Historical Assessment of Critical Metallographic Observations

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

Matlock, David K; Thomas, Larrin S; Taylor, Mark D

In the past 30+ years significant advancements have been made in the development of higher strength sheet steels with improved combinations of strength and ductility that have enabled important product improvements leading to safer, lighter weight, and more fuel efficient automobiles and in other applications. Properties of the primarily low carbon, low alloy steels are derived through careful control of time-temperature processing histories designed to produce multiphase ferritic based microstructures that include martensite and other constituents including retained austenite. The basis for these developments stems from the early work on dual-phase steels which was the subject of much interest. Inmore » response to industry needs, dual-phase steels have evolved as a unique class of advanced high strength sheet steels (AHSS) in which the thermal and mechanical processing histories have been specifically designed to produce constituent combinations for the purpose of simultaneously controlling strength and deformation behavior, i.e. stress-strain curve shapes. Improvements continue as enhanced dual-phase steels have recently been produced with finer microstructures, higher strengths, and better overall formability. Today, dual phase steels are the primary AHSS products used in vehicle manufacture, and several companies have indicated that the steels will remain as important design materials well into the future. In this presentation, fundamental results from the early work on dual-phase steels will be reviewed and assessed in light of recent steel developments. Specific contributions from industry/university cooperative research leading to product improvements will be highlighted. The historical perspective provided in the evolution of dual-phase steels represents a case-study that provides important framework and lessons to be incorporated in next generation AHSS products.« less

A new unequal-weighted triple-frequency first order ionosphere correction algorithm and its application in COMPASS

NASA Astrophysics Data System (ADS)

Liu, WenXiang; Mou, WeiHua; Wang, FeiXue

2012-03-01

As the introduction of triple-frequency signals in GNSS, the multi-frequency ionosphere correction technology has been fast developing. References indicate that the triple-frequency second order ionosphere correction is worse than the dual-frequency first order ionosphere correction because of the larger noise amplification factor. On the assumption that the variances of three frequency pseudoranges were equal, other references presented the triple-frequency first order ionosphere correction, which proved worse or better than the dual-frequency first order correction in different situations. In practice, the PN code rate, carrier-to-noise ratio, parameters of DLL and multipath effect of each frequency are not the same, so three frequency pseudorange variances are unequal. Under this consideration, a new unequal-weighted triple-frequency first order ionosphere correction algorithm, which minimizes the variance of the pseudorange ionosphere-free combination, is proposed in this paper. It is found that conventional dual-frequency first-order correction algorithms and the equal-weighted triple-frequency first order correction algorithm are special cases of the new algorithm. A new pseudorange variance estimation method based on the three carrier combination is also introduced. Theoretical analysis shows that the new algorithm is optimal. The experiment with COMPASS G3 satellite observations demonstrates that the ionosphere-free pseudorange combination variance of the new algorithm is smaller than traditional multi-frequency correction algorithms.

The Transport of Salt and Water across Isolated Rat Ileum

PubMed Central

Clarkson, T. W.

1967-01-01

The flows of sodium, potassium, and chloride under electrical and chemical gradients and of salt and water in the presence of osmotic pressure gradients are described by phenomenological equations based on the thermodynamics of irreversible processes. The aim was to give the simplest possible description, that is to postulate the least number of active transport processes and the least number of separate pathways across the intestine. On this basis, the results were consistent with the following picture of the intestine: Two channels exist across this tissue, one allowing only passive transport of ions and the other only active. In the passive channel, the predominant resistance to ion flow is friction with the water in the channel. The electroosmotic flow indicates that the passive channel is lined with negative fixed charged groups having a surface charge density of 3000 esu cm-2. The values of the ion-water frictional coefficients, and the relationship between ionic concentrations and flows indicate that the passive channel is extracellular. The active channel behaves as two membranes in series, the first membrane being semipermeable but allowing active transport of sodium, and the second membrane being similar to the passive channel. Friction with the ions in the second "membrane" is the predominant resistance to water flow. PMID:11526854

Phylogenetic identification of fungi isolated from the marine sponge Tethya aurantium and identification of their secondary metabolites.

PubMed

Wiese, Jutta; Ohlendorf, Birgit; Blümel, Martina; Schmaljohann, Rolf; Imhoff, Johannes F

2011-01-01

Fungi associated with the marine sponge Tethya aurantium were isolated and identified by morphological criteria and phylogenetic analyses based on internal transcribed spacer (ITS) regions. They were evaluated with regard to their secondary metabolite profiles. Among the 81 isolates which were characterized, members of 21 genera were identified. Some genera like Acremonium, Aspergillus, Fusarium, Penicillium, Phoma, and Trichoderma are quite common, but we also isolated strains belonging to genera like Botryosphaeria, Epicoccum, Parasphaeosphaeria, and Tritirachium which have rarely been reported from sponges. Members affiliated to the genera Bartalinia and Volutella as well as to a presumably new Phoma species were first isolated from a sponge in this study. On the basis of their classification, strains were selected for analysis of their ability to produce natural products. In addition to a number of known compounds, several new natural products were identified. The scopularides and sorbifuranones have been described elsewhere. We have isolated four additional substances which have not been described so far. The new metabolite cillifuranone (1) was isolated from Penicillium chrysogenum strain LF066. The structure of cillifuranone (1) was elucidated based on 1D and 2D NMR analysis and turned out to be a previously postulated intermediate in sorbifuranone biosynthesis. Only minor antibiotic bioactivities of this compound were found so far.

Imaging chromatin nanostructure with binding-activated localization microscopy based on DNA structure fluctuations

PubMed Central

Szczurek, Aleksander; Klewes, Ludger; Xing, Jun; Gourram, Amine; Birk, Udo; Knecht, Hans; Dobrucki, Jurek W.; Mai, Sabine

2017-01-01

Abstract Advanced light microscopy is an important tool for nanostructure analysis of chromatin. In this report we present a general concept for Single Molecule localization Microscopy (SMLM) super-resolved imaging of DNA-binding dyes based on modifying the properties of DNA and the dye. By careful adjustment of the chemical environment leading to local, reversible DNA melting and hybridization control over the fluorescence signal of the DNA-binding dye molecules can be introduced. We postulate a transient binding as the basis for our variation of binding-activated localization microscopy (BALM). We demonstrate that several intercalating and minor-groove binding DNA dyes can be used to register (optically isolate) only a few DNA-binding dye signals at a time. To highlight this DNA structure fluctuation-assisted BALM (fBALM), we applied it to measure, for the first time, nanoscale differences in nuclear architecture in model ischemia with an anticipated structural resolution of approximately 50 nm. Our data suggest that this approach may open an avenue for the enhanced microscopic analysis of chromatin nano-architecture and hence the microscopic analysis of nuclear structure aberrations occurring in various pathological conditions. It may also become possible to analyse nuclear nanostructure differences in different cell types, stages of development or environmental stress conditions. PMID:28082388

Enzymatic catalysis of anti-Baldwin ring closure in polyether biosynthesis.

PubMed

Hotta, Kinya; Chen, Xi; Paton, Robert S; Minami, Atsushi; Li, Hao; Swaminathan, Kunchithapadam; Mathews, Irimpan I; Watanabe, Kenji; Oikawa, Hideaki; Houk, Kendall N; Kim, Chu-Young

2012-03-04

Polycyclic polyether natural products have fascinated chemists and biologists alike owing to their useful biological activity, highly complex structure and intriguing biosynthetic mechanisms. Following the original proposal for the polyepoxide origin of lasalocid and isolasalocid and the experimental determination of the origins of the oxygen and carbon atoms of both lasalocid and monensin, a unified stereochemical model for the biosynthesis of polyether ionophore antibiotics was proposed. The model was based on a cascade of nucleophilic ring closures of postulated polyepoxide substrates generated by stereospecific oxidation of all-trans polyene polyketide intermediates. Shortly thereafter, a related model was proposed for the biogenesis of marine ladder toxins, involving a series of nominally disfavoured anti-Baldwin, endo-tet epoxide-ring-opening reactions. Recently, we identified Lsd19 from the Streptomyces lasaliensis gene cluster as the epoxide hydrolase responsible for the epoxide-opening cyclization of bisepoxyprelasalocid A to form lasalocid A. Here we report the X-ray crystal structure of Lsd19 in complex with its substrate and product analogue to provide the first atomic structure-to our knowledge-of a natural enzyme capable of catalysing the disfavoured epoxide-opening cyclic ether formation. On the basis of our structural and computational studies, we propose a general mechanism for the enzymatic catalysis of polyether natural product biosynthesis. © 2012 Macmillan Publishers Limited. All rights reserved

Westinghouse Small Modular Reactor passive safety system response to postulated events

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

Smith, M. C.; Wright, R. F.

2012-07-01

The Westinghouse Small Modular Reactor (SMR) is an 800 MWt (>225 MWe) integral pressurized water reactor. This paper is part of a series of four describing the design and safety features of the Westinghouse SMR. This paper focuses in particular upon the passive safety features and the safety system response of the Westinghouse SMR. The Westinghouse SMR design incorporates many features to minimize the effects of, and in some cases eliminates the possibility of postulated accidents. The small size of the reactor and the low power density limits the potential consequences of an accident relative to a large plant. Themore » integral design eliminates large loop piping, which significantly reduces the flow area of postulated loss of coolant accidents (LOCAs). The Westinghouse SMR containment is a high-pressure, compact design that normally operates at a partial vacuum. This facilitates heat removal from the containment during LOCA events. The containment is submerged in water which also aides the heat removal and provides an additional radionuclide filter. The Westinghouse SMR safety system design is passive, is based largely on the passive safety systems used in the AP1000{sup R} reactor, and provides mitigation of all design basis accidents without the need for AC electrical power for a period of seven days. Frequent faults, such as reactivity insertion events and loss of power events, are protected by first shutting down the nuclear reaction by inserting control rods, then providing cold, borated water through a passive, buoyancy-driven flow. Decay heat removal is provided using a layered approach that includes the passive removal of heat by the steam drum and independent passive heat removal system that transfers heat from the primary system to the environment. Less frequent faults such as loss of coolant accidents are mitigated by passive injection of a large quantity of water that is readily available inside containment. An automatic depressurization system is used to reduce the reactor pressure in a controlled manner to facilitate the passive injection. Long-term decay heat removal is accomplished using the passive heat removal systems augmented by heat transfer through the containment vessel to the environment. The passive injection systems are designed so that the fuel remains covered and effectively cooled throughout the event. Like during the frequent faults, the passive systems provide effective cooling without the need for ac power for seven days following the accident. Connections are available to add additional water to indefinitely cool the plant. The response of the safety systems of the Westinghouse SMR to various initiating faults has been examined. Among them, two accidents; an extended station blackout event, and a LOCA event have been evaluated to demonstrate how the plant will remain safe in the unlikely event that either should occur. (authors)« less

76 FR 43356 - Evaluations of Explosions Postulated To Occur at Nearby Facilities and on Transportation Routes...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-20

... the ``Regulatory Guides'' collection of the NRC's Library at http://www.nrc.gov/reading-rm/doc... NUCLEAR REGULATORY COMMISSION [NRC-2011-0152] Evaluations of Explosions Postulated To Occur at..., ``Evaluations of Explosions Postulated to Occur at Nearby Facilities and on Transportation Routes Near Nuclear...

Contextual representations increase analogue traumatic intrusions: evidence against a dual-representation account of peri-traumatic processing.

PubMed

Pearson, David G

2012-12-01

Information processing accounts of post-traumatic stress disorder (PTSD) state that intrusive memories emerge due to a lack of integration between perceptual and contextual trauma representations in autobiographical memory. This hypothesis was tested experimentally using an analogue trauma paradigm in which participants viewed an aversive film designed to elicit involuntary recollections. Participants viewed scenes from the film either paired with contextual information or with the contextual information omitted. After viewing the film participants were asked to record for one week any involuntary intrusions for the film using a provided intrusions diary. The results revealed a significant increase in analogue intrusions for the film when viewed with contextual information in comparison to when the film was viewed with the contextual information omitted. In contrast there was no effect of contextual information on valence ratings or voluntary memory for the film, or on the reported vividness and emotionality of the intrusions. The analogue trauma paradigm may have failed to reproduce the effect of extreme stress on encoding that is postulated to occur during PTSD. The findings have potential implications for trauma intervention as they suggest that the contextual understanding of a scene during encoding can be integral to the subsequent occurrence of traumatic intrusions. The pattern of results found in the study are inconsistent with dual-representation accounts of intrusive memory formation, and instead provide new evidence that contextual representations play a casual role in increasing the frequency of involuntary intrusions for traumatic material. Copyright © 2012 Elsevier Ltd. All rights reserved.

Dual Enrollment as a Path to Higher Education in Oregon

ERIC Educational Resources Information Center

Arthur, Michael S.

2017-01-01

This qualitative study was conducted at a community college in Oregon with a full-time enrollment of 4,954 students during the 2015-16 academic school year (National Center for Education Statistics, 2017). A phenomenological research methodology investigated the lived experiences of first-year college students who participated in a dual-enrollment…

Children's Language Ideologies in a First-Grade Dual-Language Class

ERIC Educational Resources Information Center

Lopez, Minda Morren

2012-01-01

This study explores the language ideologies of young children in a Spanish/English dual language programme in the USA. Recent studies of language ideologies in education have centred primarily on adults or older students, but this study focuses on young children from varied language backgrounds. By analysing discussions centred on children's…

Dual Language Teachers' Use of Conventional, Environmental, and Personal Resources to Support Academic Language Development

ERIC Educational Resources Information Center

Lucero, Audrey

2015-01-01

This article reports findings from a study that investigated the ways in which first-grade dual language teachers drew on various resources to instructionally support academic language development among Spanish-English emergent bilingual students. Classroom observations, semistructured interviews, and document collection were conducted over a…

Dual mode cobaloxime crystals: Acceleration of trans-cis photochromic reaction rate by photoisomerization

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

Sekine, Akiko, E-mail: asekine@chem.titech.ac.jp

2016-08-26

Our recent results on the photochromic reactions in dual mode cobaloxime crystals containing azobenzene derivatives are briefly reviewed. This work represents the first step toward the design of functional materials which can be controlled by two independent external stimuli, one by visible light and the other by UV radiation.

Improving the signal subtle feature extraction performance based on dual improved fractal box dimension eigenvectors

NASA Astrophysics Data System (ADS)

Chen, Xiang; Li, Jingchao; Han, Hui; Ying, Yulong

2018-05-01

Because of the limitations of the traditional fractal box-counting dimension algorithm in subtle feature extraction of radiation source signals, a dual improved generalized fractal box-counting dimension eigenvector algorithm is proposed. First, the radiation source signal was preprocessed, and a Hilbert transform was performed to obtain the instantaneous amplitude of the signal. Then, the improved fractal box-counting dimension of the signal instantaneous amplitude was extracted as the first eigenvector. At the same time, the improved fractal box-counting dimension of the signal without the Hilbert transform was extracted as the second eigenvector. Finally, the dual improved fractal box-counting dimension eigenvectors formed the multi-dimensional eigenvectors as signal subtle features, which were used for radiation source signal recognition by the grey relation algorithm. The experimental results show that, compared with the traditional fractal box-counting dimension algorithm and the single improved fractal box-counting dimension algorithm, the proposed dual improved fractal box-counting dimension algorithm can better extract the signal subtle distribution characteristics under different reconstruction phase space, and has a better recognition effect with good real-time performance.

Synthesis and Biological Evaluation of the First Dual Tyrosyl-DNA Phosphodiesterase I (Tdp1) - Topoisomerase I (Top1) Inhibitors

PubMed Central

Nguyen, Trung Xuan; Morrell, Andrew; Conda-Sheridan, Martin; Marchand, Christophe; Agama, Keli; Bermingam, Alun; Stephen, Andrew G.; Chergui, Adel; Naumova, Alena; Fisher, Robert; O’Keefe, Barry R.; Pommier, Yves; Cushman, Mark

2012-01-01

Substances with dual tyrosyl-DNA phosphodiesterase I - topoisomerase I inhibitory activity in one low molecular weight compound would constitute a unique class of anticancer agents that could potentially have significant advantages over drugs that work against the individual enzymes. The present study demonstrates the successful synthesis and evaluation of the first dual Top1-Tdp1 inhibitors, which are based on the indenoisoquinoline chemotype. One bis(indenoisoquinoline) had significant activity against human Tdp1 (IC50 = 1.52 ± 0.05 μM), and it was also equipotent to camptothecin as a Top1 inhibitor. Significant insights into enzyme-drug interactions were gained via structure-activity relationship studies of the series. The present results also document the failure of the previously reported sulfonyl ester pharmacophore to confer Tdp1 inhibition in this indenoisoquinoline class of inhibitors, even though it was demonstrated to work well for the steroid NSC 88915 (7). The current study will facilitate future efforts to optimize dual Top1-Tdp1 inhibitors. PMID:22536944

Marrow Adipose Tissue Quantification of the Lumbar Spine by Using Dual-Energy CT and Single-Voxel 1H MR Spectroscopy: A Feasibility Study

PubMed Central

Daley, Scott M.; Kalra, Mannudeep K.; Brown, J. Keenan; Miller, Karen K.; Torriani, Martin

2015-01-01

Purpose To test the performance of dual-energy computed tomography (CT) in the assessment of marrow adipose tissue (MAT) content of the lumbar spine by using proton (hydrogen 1 [1H]) magnetic resonance (MR) spectroscopy as a reference standard and to determine the influence of MAT on the assessment of bone mineral density (BMD). Materials and Methods This study was institutional review board approved and complied with HIPAA guidelines. Written informed consent was obtained. Twelve obese osteopenic but otherwise healthy subjects (mean age ± standard deviation, 43 years ± 13) underwent 3-T 1H MR spectroscopy of the L2 vertebra by using a point-resolved spatially localized spectroscopy sequence without water suppression. The L2 vertebra was scanned with dual-energy CT (80 and 140 kV) by using a dual-source multi–detector row CT scanner with a calibration phantom. Mean basis material composition relative to the phantom was estimated in the L2 vertebra. Volumetric BMD was measured with and without correction for MAT. Bland-Altman 95% limits of agreement and Pearson correlation coefficients were calculated. Results There was excellent agreement between 1H MR spectroscopy and dual-energy CT, with a mean difference in fat fraction of −0.02 between the techniques, with a 95% confidence interval of −0.24, 0.20. There was a strong correlation between marrow fat fraction obtained with 1H MR spectroscopy and that obtained with dual-energy CT (r = 0.91, P < .001). The presence of MAT led to underestimation of BMD, and this bias increased with increasing MAT content (P < .001). Conclusion Dual-energy CT can be used to assess MAT content and BMD of the lumbar spine in a single examination and provides data that closely agree and correlate with 1H MR spectroscopy data. © RSNA, 2015 PMID:25988401

Dual-modality wide-field photothermal quantitative phase microscopy and depletion of cell populations

NASA Astrophysics Data System (ADS)

Turko, Nir A.; Barnea, Itay; Blum, Omry; Korenstein, Rafi; Shaked, Natan T.

2015-03-01

We review our dual-modality technique for quantitative imaging and selective depletion of populations of cells based on wide-field photothermal (PT) quantitative phase imaging and simultaneous PT cell extermination. The cells are first labeled by plasmonic gold nanoparticles, which evoke local plasmonic resonance when illuminated by light in a wavelength corresponding to their specific plasmonic resonance peak. This reaction creates changes of temperature, resulting in changes of phase. This phase changes are recorded by a quantitative phase microscope (QPM), producing specific imaging contrast, and enabling bio-labeling in phase microscopy. Using this technique, we have shown discrimination of EGFR over-expressing (EGFR+) cancer cells from EGFR under-expressing (EGFR-) cancer cells. Then, we have increased the excitation power in order to evoke greater temperatures, which caused specific cell death, all under real-time phase acquisition using QPM. Close to 100% of all EGFR+ cells were immediately exterminated when illuminated with the strong excitation beam, while all EGFR- cells survived. For the second experiment, in order to simulate a condition where circulating tumor cells (CTCs) are present in blood, we have mixed the EGFR+ cancer cells with white blood cells (WBCs) from a healthy donor. Here too, we have used QPM to observe and record the phase of the cells as they were excited for selective visualization and then exterminated. The WBCs survival rate was over 95%, while the EGFR+ survival rate was under 5%. The technique may be the basis for real-time detection and controlled treatment of CTCs.

Molecular Determinants of Magnolol Targeting Both RXRα and PPARγ

PubMed Central

Chen, Lili; Chen, Jing; Hu, Lihong; Jiang, Hualiang; Shen, Xu

2011-01-01

Nuclear receptors retinoic X receptor α (RXRα) and peroxisome proliferator activated receptor γ (PPARγ) function potently in metabolic diseases, and are both important targets for anti-diabetic drugs. Coactivation of RXRα and PPARγ is believed to synergize their effects on glucose and lipid metabolism. Here we identify the natural product magnolol as a dual agonist targeting both RXRα and PPARγ. Magnolol was previously reported to enhance adipocyte differentiation and glucose uptake, ameliorate blood glucose level and prevent development of diabetic nephropathy. Although magnolol can bind and activate both of these two nuclear receptors, the transactivation assays indicate that magnolol exhibits biased agonism on the transcription of PPAR-response element (PPRE) mediated by RXRα:PPARγ heterodimer, instead of RXR-response element (RXRE) mediated by RXRα:RXRα homodimer. To further elucidate the molecular basis for magnolol agonism, we determine both the co-crystal structures of RXRα and PPARγ ligand-binding domains (LBDs) with magnolol. Structural analyses reveal that magnolol adopts its two 5-allyl-2-hydroxyphenyl moieties occupying the acidic and hydrophobic cavities of RXRα L-shaped ligand-binding pocket, respectively. While, two magnolol molecules cooperatively accommodate into PPARγ Y-shaped ligand-binding pocket. Based on these two complex structures, the key interactions for magnolol activating RXRα and PPARγ are determined. As the first report on the dual agonist targeting RXRα and PPARγ with receptor-ligand complex structures, our results are thus expected to help inspect the potential pharmacological mechanism for magnolol functions, and supply useful hits for nuclear receptor multi-target ligand design. PMID:22140563

Dual-frequency ultrasound imaging and therapeutic bilaminar array using frequency selective isolation layer.

PubMed

Azuma, Takashi; Ogihara, Makoto; Kubota, Jun; Sasaki, Akira; Umemura, Shin-ichiro; Furuhata, Hiroshi

2010-05-01

A new ultrasound array transducer with two different optimal frequencies designed for diagnosis and therapy integration in Doppler imaging-based transcranial sonothrombolysis is described. Previous studies have shown that respective frequencies around 0.5 and 2 MHz are suitable for sonothrombolysis and Doppler imaging. Because of the small acoustic window available for transcranial ultrasound exposure, it is highly desirable that both therapeutic and diagnostic ultrasounds pass through the same aperture with high efficiency. To achieve such a dual-frequency array transducer, we propose a bilaminar array, having an array for imaging and another for therapy, with a frequency selective isolation layer between the two arrays. The function of this layer is to isolate the imaging array from the therapy array at 2 MHz without disturbing the 0.5-MHz ultrasound transmission. In this study, we first used a 1-D model including two lead zirconate titanate (PZT) layers separated by an isolation layer for intuitive understanding of the phenomena. After that, we optimized the acoustic impedance and thickness of the isolation layer by analyzing pulse propagation in a 2-D model by conducting a numerical simulation with commercially available software. The optimal acoustic impedance and thickness are 3 to 4 MRayI and lambda/10, respectively. On the basis of the optimization, a prototype array transducer was fabricated, and the spatial resolutions of the Doppler images it obtained were found to be practically the same as those obtained through conventional imaging array transducers.

A multistep damage recognition mechanism for global genomic nucleotide excision repair

PubMed Central

Sugasawa, Kaoru; Okamoto, Tomoko; Shimizu, Yuichiro; Masutani, Chikahide; Iwai, Shigenori; Hanaoka, Fumio

2001-01-01

A mammalian nucleotide excision repair (NER) factor, the XPC–HR23B complex, can specifically bind to certain DNA lesions and initiate the cell-free repair reaction. Here we describe a detailed analysis of its binding specificity using various DNA substrates, each containing a single defined lesion. A highly sensitive gel mobility shift assay revealed that XPC–HR23B specifically binds a small bubble structure with or without damaged bases, whereas dual incision takes place only when damage is present in the bubble. This is evidence that damage recognition for NER is accomplished through at least two steps; XPC–HR23B first binds to a site that has a DNA helix distortion, and then the presence of injured bases is verified prior to dual incision. Cyclobutane pyrimidine dimers (CPDs) were hardly recognized by XPC–HR23B, suggesting that additional factors may be required for CPD recognition. Although the presence of mismatched bases opposite a CPD potentiated XPC–HR23B binding, probably due to enhancement of the helix distortion, cell-free excision of such compound lesions was much more efficient than expected from the observed affinity for XPC–HR23B. This also suggests that additional factors and steps are required for the recognition of some types of lesions. A multistep mechanism of this sort may provide a molecular basis for ensuring the high level of damage discrimination that is required for global genomic NER. PMID:11238373

A multistep damage recognition mechanism for global genomic nucleotide excision repair.

PubMed

Sugasawa, K; Okamoto, T; Shimizu, Y; Masutani, C; Iwai, S; Hanaoka, F

2001-03-01

A mammalian nucleotide excision repair (NER) factor, the XPC-HR23B complex, can specifically bind to certain DNA lesions and initiate the cell-free repair reaction. Here we describe a detailed analysis of its binding specificity using various DNA substrates, each containing a single defined lesion. A highly sensitive gel mobility shift assay revealed that XPC-HR23B specifically binds a small bubble structure with or without damaged bases, whereas dual incision takes place only when damage is present in the bubble. This is evidence that damage recognition for NER is accomplished through at least two steps; XPC-HR23B first binds to a site that has a DNA helix distortion, and then the presence of injured bases is verified prior to dual incision. Cyclobutane pyrimidine dimers (CPDs) were hardly recognized by XPC-HR23B, suggesting that additional factors may be required for CPD recognition. Although the presence of mismatched bases opposite a CPD potentiated XPC-HR23B binding, probably due to enhancement of the helix distortion, cell-free excision of such compound lesions was much more efficient than expected from the observed affinity for XPC-HR23B. This also suggests that additional factors and steps are required for the recognition of some types of lesions. A multistep mechanism of this sort may provide a molecular basis for ensuring the high level of damage discrimination that is required for global genomic NER.

Meteorological Observations and System Performance From the NASA D3R's First 5 Years

NASA Technical Reports Server (NTRS)

Chandrasekar, V.; Beauchamp, Robert M.; Vega, Manuel; Chen, Haonan; Kumar, Mohit; Joshil, Shashank; Schwaller, Mathew; Petersen, Walter; Wolff, David

2017-01-01

The NASA dual-frequency, dual-polarization, Doppler radar (D3R) was conceived and developed to support ground validation (GV) operations of the Global Precipitation Measurement (GPM) mission. The D3R operates in the same frequencies bands, Ku- and Ka-band, as GPMs dual-frequency precipitation radar enabling direct comparisons of microphysical observations of precipitation. To support the GPM GVmission, D3R substantively participated in four field campaigns in North America with diverse geographic features covering both winter and summer conditions.

One- and Two-Photon Uncaging: Carbazole Fused o-Hydroxycinnamate Platform for Dual Release of Alcohols (Same or Different) with Real-Time Monitoring.

PubMed

Venkatesh, Yarra; Srivastava, Hemant Kumar; Bhattacharya, S; Mehra, Muneshwar; Datta, P K; Bandyopadhyay, S; Singh, N D Pradeep

2018-04-20

A one- and two-photon activated photoremovable protecting group (PRPG) was designed based on a carbazole fused o-hydroxycinnamate platform for the dual (same or different) release of alcohols. The mechanism for the dual release proceeds through a stepwise pathway and also monitors the first and second photorelease in real time by an increase in fluorescence intensity and color change, respectively. Further, its application in staining live neurons and ex vivo imaging with two-photon excitation is shown.

Radar Differential Phase Signatures of Ice Orientation for the Prediction of Lightning Initiation and Cessation

NASA Technical Reports Server (NTRS)

Carey, L.D.; Petersen, W.A.; Deierling, W.

2009-01-01

The majority of lightning-related casualties typically occur during thunderstorm initiation (e.g., first flash) or dissipation (e.g., last flash). The physics of electrification and lightning production during thunderstorm initiation is fairly well understood. As such, the literature includes a number of studies presenting various radar techniques (using reflectivity and, if available, other dual-polarimetric parameters) for the anticipation of initial electrification and first lightning flash. These radar techniques have shown considerable skill at forecasting first flash. On the other hand, electrical processes and lightning production during thunderstorm dissipation are not nearly as well understood and few, if any, successful techniques have been developed to anticipate the last flash and subsequent cessation of lightning. One promising approach involves the use of dual-polarimetric radar variables to infer the presence of oriented ice crystals in lightning producing storms. In the absence of strong vertical electric fields, ice crystals fall with their largest (semi-major) axis in the horizontal associated with gravitational and aerodynamic forces. In thunderstorms, strong vertical electric fields (100-200 kV m(sup -1)) have been shown to orient small (less than 2 mm) ice crystals such that their semi-major axis is vertical (or nearly vertical). After a lightning flash, the electric field is typically relaxed and prior radar research suggests that ice crystals rapidly resume their preferred horizontal orientation. In active thunderstorms, the vertical electric field quickly recovers and the ice crystals repeat this cycle of orientation for each nearby flash. This change in ice crystal orientation from primarily horizontal to vertical during the development of strong vertical electric fields prior to a lightning flash forms the physical basis for anticipating lightning initiation and, potentially, cessation. Research has shown that radar reflectivity (Z) and other co-polar back-scattering radar measurements like differential reflectivity (Z(sub dr)) typically measured by operational dual-polarimetric radars are not sensitive to these changes in ice crystal orientation. However, prior research has demonstrated that oriented ice crystals cause significant propagation effects that can be routinely measured by most dual-polarimetric radars from X-band (3 cm) to S-band (10 cm) wavelengths using the differential propagation phase shift (often just called differential phase, phi(sub dp)) or its range derivative, the specific differential phase (K(sub dp)). Advantages of the differential phase include independence from absolute or relative power calibration, attenuation, differential attenuation and relative insensitivity to ground clutter and partial beam occultation effects (as long as the signal remains above noise). In research mode, these sorts of techniques have been used to anticipate initial cloud electrification, lightning initiation, and cessation. In this study, we develop a simplified model of ice crystal size, shape, orientation, dielectric, and associated radar scattering and propagation effects in order to simulate various idealized scenarios of ice crystals responding to a hypothetical electric field and their dual-polarimetric radar signatures leading up to lightning initiation and particularly cessation. The sensitivity of the K(sub dp) ice orientation signature to various ice properties and radar wavelength will be explored. Since K(sub dp) is proportional to frequency in the Rayleigh- Gans scattering regime, the ice orientation signatures should be more obvious at higher (lower) frequencies (wavelengths). As a result, simulations at radar wavelengths from 10 cm down to 1 cm (Ka-band) will be conducted. Resonance effects will be considered using the T-matrix method. Since most K(sub dp) Vbased observations have been shown at S-band, we will present ice orientation signatures from C-band (UAH/NASA ARMOR) and X-bd (UAH MAX) dual-polarimetric radars located in Northern Alabama. Issues related to optimal radar scanning for the detection of oriented ice will be discussed. Preliminary suggestions on how these differential phase signatures of oriented ice could contribute to lightning initiation and cessation algorithms will be presented.

The determinants of response time in a repeated constant-sum game: A robust Bayesian hierarchical dual-process model.

PubMed

Spiliopoulos, Leonidas

2018-03-01

The investigation of response time and behavior has a long tradition in cognitive psychology, particularly for non-strategic decision-making. Recently, experimental economists have also studied response time in strategic interactions, but with an emphasis on either one-shot games or repeated social-dilemmas. I investigate the determinants of response time in a repeated (pure-conflict) game, admitting a unique mixed strategy Nash equilibrium, with fixed partner matching. Response times depend upon the interaction of two decision models embedded in a dual-process framework (Achtziger and Alós-Ferrer, 2014; Alós-Ferrer, 2016). The first decision model is the commonly used win-stay/lose-shift heuristic and the second the pattern-detecting reinforcement learning model in Spiliopoulos (2013b). The former is less complex and can be executed more quickly than the latter. As predicted, conflict between these two models (i.e., each one recommending a different course of action) led to longer response times than cases without conflict. The dual-process framework makes other qualitative response time predictions arising from the interaction between the existence (or not) of conflict and which one of the two decision models the chosen action is consistent with-these were broadly verified by the data. Other determinants of RT were hypothesized on the basis of existing theory and tested empirically. Response times were strongly dependent on the actions chosen by both players in the previous rounds and the resulting outcomes. Specifically, response time was shortest after a win in the previous round where the maximum possible payoff was obtained; response time after losses was significantly longer. Strongly auto-correlated behavior (regardless of its sign) was also associated with longer response times. I conclude that, similar to other tasks, there is a strong coupling in repeated games between behavior and RT, which can be exploited to further our understanding of decision making. Copyright © 2017 Elsevier B.V. All rights reserved.

The metabolic response of P. putida KT2442 producing high levels of polyhydroxyalkanoate under single- and multiple-nutrient-limited growth: Highlights from a multi-level omics approach

PubMed Central

2012-01-01

Background Pseudomonas putida KT2442 is a natural producer of polyhydroxyalkanoates (PHAs), which can substitute petroleum-based non-renewable plastics and form the basis for the production of tailor-made biopolymers. However, despite the substantial body of work on PHA production by P. putida strains, it is not yet clear how the bacterium re-arranges its whole metabolism when it senses the limitation of nitrogen and the excess of fatty acids as carbon source, to result in a large accumulation of PHAs within the cell. In the present study we investigated the metabolic response of KT2442 using a systems biology approach to highlight the differences between single- and multiple-nutrient-limited growth in chemostat cultures. Results We found that 26, 62, and 81% of the cell dry weight consist of PHA under conditions of carbon, dual, and nitrogen limitation, respectively. Under nitrogen limitation a specific PHA production rate of 0.43 (g·(g·h)-1) was obtained. The residual biomass was not constant for dual- and strict nitrogen-limiting growth, showing a different feature in comparison to other P. putida strains. Dual limitation resulted in patterns of gene expression, protein level, and metabolite concentrations that substantially differ from those observed under exclusive carbon or nitrogen limitation. The most pronounced differences were found in the energy metabolism, fatty acid metabolism, as well as stress proteins and enzymes belonging to the transport system. Conclusion This is the first study where the interrelationship between nutrient limitations and PHA synthesis has been investigated under well-controlled conditions using a system level approach. The knowledge generated will be of great assistance for the development of bioprocesses and further metabolic engineering work in this versatile organism to both enhance and diversify the industrial production of PHAs. PMID:22433058

Holography in Lovelock Chern-Simons AdS gravity

NASA Astrophysics Data System (ADS)

Cvetković, Branislav; Miskovic, Olivera; Simić, Dejan

2017-08-01

We analyze holographic field theory dual to Lovelock Chern-Simons anti-de Sitter (AdS) gravity in higher dimensions using first order formalism. We first find asymptotic symmetries in the AdS sector showing that they consist of local translations, local Lorentz rotations, dilatations and non-Abelian gauge transformations. Then, we compute 1-point functions of energy-momentum and spin currents in a dual conformal field theory and write Ward identities. We find that the holographic theory possesses Weyl anomaly and also breaks non-Abelian gauge symmetry at the quantum level.

First demonstration and field trial on multi-user UDWDM-PON full duplex PSK-PSK with single monolithic integrated dual-output-DFB-SOA based ONUs.

PubMed

Chu, GuangYong; Maho, Anaëlle; Cano, Iván; Polo, Victor; Brenot, Romain; Debrégeas, Hélène; Prat, Josep

2016-10-15

We demonstrate a monolithically integrated dual-output DFB-SOA, and conduct the field trial on a multi-user bidirectional coherent ultradense wavelength division multiplexing-passive optical network (UDWDM-PON). To the best of our knowledge, this is the first achievement of simplified single integrated laser-based neighboring coherent optical network units (ONUs) with a 12.5 GHz channel spaced ultra-dense access network, including both downstream and upstream, taking the benefits of low footprint and low-temperature dependence.

The Light-Velocity Postulate: The Essential Difference between the Theories of Lorentz-Poincare and Einstein

ERIC Educational Resources Information Center

Abiko, Seiya

2005-01-01

Einstein, who had already developed the light-quantum theory, knew the inadequacy of Maxwell's theory in the microscopic sphere. Therefore, in writing his paper on special relativity, he had to set up the light-velocity postulate independently of the relativity postulate in order to make the electromagnetic foundation of physics compatible with…

A Theory of Vocational Development for Women.

ERIC Educational Resources Information Center

Zytowski, Donald G.

In postulate I, the modal life role for women is described as that of the homemaker. Postulate II proposes that the nature of the woman's role is not static, ultimately bearing no distinction from that of men. Postulate III states that the role of women is orderly and developmental, divisible into major segments according to the major task in…

Simultaneous measurement of temperature and emissivity of lunar regolith simulant using dual-channel millimeter-wave radiometry.

PubMed

McCloy, J S; Sundaram, S K; Matyas, J; Woskov, P P

2011-05-01

Millimeter wave (MMW) radiometry can be used for simultaneous measurement of emissivity and temperature of materials under extreme environments (high temperature, pressure, and corrosive environments). The state-of-the-art dual channel MMW passive radiometer with active interferometric capabilities at 137 GHz described here allows for radiometric measurements of sample temperature and emissivity up to at least 1600 °C with simultaneous measurement of sample surface dynamics. These capabilities have been used to demonstrate dynamic measurement of melting of powders of simulated lunar regolith and static measurement of emissivity of solid samples. The paper presents the theoretical background and basis for the dual-receiver system, describes the hardware in detail, and demonstrates the data analysis. Post-experiment analysis of emissivity versus temperature allows further extraction from the radiometric data of millimeter wave viewing beam coupling factors, which provide corroboratory evidence to the interferometric data of the process dynamics observed. These results show the promise of the MMW system for extracting quantitative and qualitative process parameters for industrial processes and access to real-time dynamics of materials behavior in extreme environments.

Fabrication of Ag-decorated BiOBr-mBiVO4 dual heterojunction composite with enhanced visible light photocatalytic performance for degradation of malachite green

NASA Astrophysics Data System (ADS)

Regmi, Chhabilal; Dhakal, Dipesh; Kim, Tae-Ho; Yamaguchi, Takutaro; Wohn Lee, Soo

2018-04-01

A visible light active Ag-decorated BiVO4-BiOBr dual heterojunction photocatalyst was prepared using a facile hydrothermal method, followed by the photodeposition of Ag. The photocatalytic activity of the synthesized samples was investigated by monitoring the change in malachite green (MG) concentration upon visible light irradiation. The synthesized sample was highly effective for the degradation of non-biodegradable MG. The enhanced activity observed was ascribed to the efficient separation and transfer of charge carriers across the dual heterojunction structure as verified by photoluminescence measurements. The removal of MG was primarily initiated by hydroxyl radicals and holes based on scavenger’s effect. To gain insight into the degradation mechanism, both high performance liquid chromatography and high resolution-quantitative time of flight, electrospray ionization mass spectrometry measurements during the degradation process were carried out. The degradation primarily followed the hydroxylation and N-demethylation process. A possible reaction pathway is proposed on the basis of all the information obtained under various experimental conditions.

SERS-Fluorescence Dual-Mode pH-Sensing Method Based on Janus Microparticles.

PubMed

Yue, Shuai; Sun, Xiaoting; Wang, Ning; Wang, Yaning; Wang, Yue; Xu, Zhangrun; Chen, Mingli; Wang, Jianhua

2017-11-15

A surface-enhanced Raman scattering (SERS)-fluorescence dual-mode pH-sensing method based on Janus microgels was developed, which combined the advantages of high specificity offered by SERS and fast imaging afforded by fluorescence. Dual-mode probes, pH-dependent 4-mercaptobenzoic acid, and carbon dots were individually encapsulated in the independent hemispheres of Janus microparticles fabricated via a centrifugal microfluidic chip. On the basis of the obvious volumetric change of hydrogels in different pHs, the Janus microparticles were successfully applied for sensitive and reliable pH measurement from 1.0 to 8.0, and the two hemispheres showed no obvious interference. The proposed method addressed the limitation that sole use of the SERS-based pH sensing usually failed in strong acidic media. The gastric juice pH and extracellular pH change were measured separately in vitro using the Janus microparticles, which confirmed the validity of microgels for pH sensing. The microparticles exhibited good stability, reversibility, biocompatibility, and ideal semipermeability for avoiding protein contamination, and they have the potential to be implantable sensors to continuously monitor pH in vivo.

Dropping Out or Keeping Up? Early-Dropouts, Late-Dropouts, and Maintainers Differ in Their Automatic Evaluations of Exercise Already before a 14-Week Exercise Course.

PubMed

Antoniewicz, Franziska; Brand, Ralf

2016-01-01

The aim of this study was to examine how automatic evaluations of exercising (AEE) varied according to adherence to an exercise program. Eighty-eight participants (24.98 years ± 6.88; 51.1% female) completed a Brief-Implicit Association Task assessing their AEE, positive and negative associations to exercising at the beginning of a 3-month exercise program. Attendance data were collected for all participants and used in a cluster analysis of adherence patterns. Three different adherence patterns (52 maintainers, 16 early dropouts, 20 late dropouts; 40.91% overall dropouts) were detected using cluster analyses. Participants from these three clusters differed significantly with regard to their positive and negative associations to exercising before the first course meeting ([Formula: see text] = 0.07). Discriminant function analyses revealed that positive associations to exercising was a particularly good discriminating factor. This is the first study to provide evidence of the differential impact of positive and negative associations on exercise behavior over the medium term. The findings contribute to theoretical understanding of evaluative processes from a dual-process perspective and may provide a basis for targeted interventions.

Recommendations for the Pharmacological Management of Neuropathic Pain: An Overview and Literature Update

PubMed Central

Dworkin, Robert H.; O'Connor, Alec B.; Audette, Joseph; Baron, Ralf; Gourlay, Geoffrey K.; Haanpää, Maija L.; Kent, Joel L.; Krane, Elliot J.; LeBel, Alyssa A.; Levy, Robert M.; Mackey, Sean C.; Mayer, John; Miaskowski, Christine; Raja, Srinivasa N.; Rice, Andrew S. C.; Schmader, Kenneth E.; Stacey, Brett; Stanos, Steven; Treede, Rolf-Detlef; Turk, Dennis C.; Walco, Gary A.; Wells, Christopher D.

2010-01-01

The Neuropathic Pain Special Interest Group of the International Association for the Study of Pain recently sponsored the development of evidence-based guidelines for the pharmacological treatment of neuropathic pain. Tricyclic antidepressants, dual reuptake inhibitors of serotonin and norepinephrine, calcium channel α2-δ ligands (ie, gabapentin and pregabalin), and topical lidocaine were recommended as first-line treatment options on the basis of the results of randomized clinical trials. Opioid analgesics and tramadol were recommended as second-line treatments that can be considered for first-line use in certain clinical circumstances. Results of several recent clinical trials have become available since the development of these guidelines. These studies have examined botulinum toxin, high-concentration capsaicin patch, lacosamide, selective serotonin reuptake inhibitors, and combination therapies in various neuropathic pain conditions. The increasing number of negative clinical trials of pharmacological treatments for neuropathic pain and ambiguities in the interpretation of these negative trials must also be considered in developing treatment guidelines. The objectives of the current article are to review the Neuropathic Pain Special Interest Group guidelines for the pharmacological management of neuropathic pain and to provide a brief overview of these recent studies. PMID:20194146

Dropping Out or Keeping Up? Early-Dropouts, Late-Dropouts, and Maintainers Differ in Their Automatic Evaluations of Exercise Already before a 14-Week Exercise Course

PubMed Central

Antoniewicz, Franziska; Brand, Ralf

2016-01-01

The aim of this study was to examine how automatic evaluations of exercising (AEE) varied according to adherence to an exercise program. Eighty-eight participants (24.98 years ± 6.88; 51.1% female) completed a Brief-Implicit Association Task assessing their AEE, positive and negative associations to exercising at the beginning of a 3-month exercise program. Attendance data were collected for all participants and used in a cluster analysis of adherence patterns. Three different adherence patterns (52 maintainers, 16 early dropouts, 20 late dropouts; 40.91% overall dropouts) were detected using cluster analyses. Participants from these three clusters differed significantly with regard to their positive and negative associations to exercising before the first course meeting (ηp2 = 0.07). Discriminant function analyses revealed that positive associations to exercising was a particularly good discriminating factor. This is the first study to provide evidence of the differential impact of positive and negative associations on exercise behavior over the medium term. The findings contribute to theoretical understanding of evaluative processes from a dual-process perspective and may provide a basis for targeted interventions. PMID:27313559

Impact of acid and oxidative modifications, single or dual, of sorghum starch on biodegradable films.

PubMed

Biduski, Bárbara; Silva, Francine Tavares da; Silva, Wyller Max da; Halal, Shanise Lisie de Mello El; Pinto, Vania Zanella; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

2017-01-01

The objective of this study was to evaluate the effects of acid and oxidation modifications on sorghum starch, as well as the effect of dual modification of starch on the physical, morphological, mechanical, and barrier properties of biodegradable films. The acid modification was performed with 3% lactic acid and the oxidation was performed with 1.5% active chlorine. For dual modification, the acid modification was performed first, followed by oxidation under the same conditions as above. Both films of the oxidized starches, single and dual, had increased stiffness, providing a higher tensile strength and lower elongation when compared to films based on native and single acid modified starches. However, the dual modification increased the water vapor permeability of the films without changing their solubility. The increase in sorghum starch concentration in the filmogenic solution increased the thickness, water vapor permeability, and elongation of the films. Copyright © 2016. Published by Elsevier Ltd.

Pulse dynamics of dual-wavelength dissipative soliton resonances and domain wall solitons in a Tm fiber laser with fiber-based Lyot filter.

PubMed

Wang, Pan; Zhao, Kangjun; Xiao, Xiaosheng; Yang, Changxi

2017-11-27

We report on the first demonstration of dual-wavelength square-wave pulses in a thulium-doped fiber laser. Under appropriate cavity parameters, dual-wavelength dissipative soliton resonances (DSRs) and domain wall solitons (DWSs) are successively obtained. Meanwhile, dark pulses generation is achieved at the dual-wavelength DWSs region due to the overlap of the two domain wall pulses. The fiber-based Lyot filter, conducted by inserting PMF between an in-line PBS and a PD-ISO, facilitates the generation of dual-wavelength operation. The polarization-resolved investigation suggests that the cross coupling between two orthogonal polarization components in the high nonlinear fiber plays an important role in the square-wave pulses formation. The investigation may be helpful for further understanding the square-wave pulse formation and has potential in application filed of multi-wavelength pulsed fiber lasers.

Smart design of a long-period fiber grating refractive index sensor based on dual-peak resonance near the phase-matching turning point.

PubMed

Ling, Qiang; Gu, Zhengtian; Gao, Kan

2018-04-01

This paper presents a smart design way for the long-period fiber grating (LPFG) refractive index sensor, which is based on high sensitivity of LPFG near phase-matching turning point (PMTP) to the surrounding refractive index (SRI). On the basis of the coupled mode theory of LPFG, cladding etching and film coating have opposite effects on the shift of the dual peaks. Therefore, an LPFG can be controlled by the cladding etching and film coating successively, until it operates near PMTP. Experimentally, an LPFG operating near PMTP was fabricated, and the glycerol solution concentration monitoring test was performed. The results show that the sensitivity of this LPFG to the SRI is as high as 5602 nm/refractive index unit.

In Vivo Antiviral Activity of 1,3-Bis(2-Chloroethyl)-1-Nitrosourea

PubMed Central

Sidwell, Robert W.; Dixon, Glen J.; Sellers, Sara M.; Schabel, Frank M.

1965-01-01

A prolongation in the lives of Swiss mice inoculated intracerebrally with lymphocytic choriomeningitis virus (LCM) was observed after treatment with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). A variety of treatment schedules, including therapy once or twice daily up to 17 days and single treatments at various times after virus inoculation, were employed. Virus titers ranging to greater than 104 were detected in the blood and brains of surviving drug-treated animals. In three comparative studies in which different treatment schedules were used, BCNU was shown to exert a protective effect approximately equal to that of methotrexate in LCM virus-infected mice. Tests were also carried out to investigate the activity of BCNU in mice experimentally infected with eastern equine encephalomyelitis (EEE) virus, western equine encephalomyelitis virus, Semliki Forest (SF) virus, herpes simplex virus, influenza virus strain PR8, vaccinia virus strain WR, Rous sarcoma virus, Friend leukemia virus (FLV), and poliovirus. Slight increases in life span were observed in the treated EEE, SF, and influenza PR8 virus-infected animals. Significant reduction in splenomegaly in FLV-infected animals treated with BCNU was demonstrated. The possible mechanisms of LCM virus inhibition by BCNU, on the basis of these and other studies, were postulated to be either specific antiviral activity or inhibition of “lethal” immune response to the LCM virus. Each of these postulates is discussed. PMID:14339266

The keloid phenomenon: progress toward a solution.

PubMed

Louw, Louise

2007-01-01

For centuries, keloids have been an enigma and despite considerable research to unravel this phenomenon no universally accepted treatment protocol currently exists. Historically, the etiology of keloids has been hypothesized by multiple different theories; however, a more contemporary view postulates a multifactoral basis for this disorder involving nutritional, biochemical, immunological, and genetic factors that play a role in this abnormal wound healing. Critical to the process of preventing or managing keloids is the need to locally control fibroblasts and their activities at the wound site. In recent years, considerable evidence has accumulated demonstrating the importance of fatty acids and bioactive lipids in health and disease, especially those involving inflammatory disorders or immune dysfunction. If hypertrophic scarring and keloid formation can be argued to have significant inflammatory histories, then it is possible to postulate a role for lipids in their etiology and potentially in their treatment. This report briefly visits past views and theories on keloid formation and treatment, and offers a theoretical rationale for considering adjuvant fatty acid therapy for keloid management. Sufficient scientific evidence in support of fatty acid strategies for the prevention and treatment of keloids currently exists, which offer opportunities to bridge the gap between the laboratory and the clinic. The intent of this paper is to serve as a basic guideline for researchers, nutritionists, and clinicians interested in keloids and to propose new directions for keloid management.

Creating ISO/EN 13606 archetypes based on clinical information needs.

PubMed

Rinner, Christoph; Kohler, Michael; Hübner-Bloder, Gudrun; Saboor, Samrend; Ammenwerth, Elske; Duftschmid, Georg

2011-01-01

Archetypes model individual EHR contents and build the basis of the dual-model approach used in the ISO/EN 13606 EHR architecture. We present an approach to create archetypes using an iterative development process. It includes automated generation of electronic case report forms from archetypes. We evaluated our approach by developing 128 archetypes which represent 446 clinical information items from the diabetes domain.

A New DEEL for An Old Problem: Social Justice at the Core

ERIC Educational Resources Information Center

Storey, Valerie A.; Beeman, Tom

2006-01-01

New DEEL does not refer to a specific policy or reform, but rather to an ideology, unencumbered by international borders and domestic politics. In this paper, we first endeavor to identify the rhetoric of New DEEL and social justice, and the reality of its implementation in schools today; spending time on the NCLB Act which we postulate is a major…

Polymeric and Molecular Materials for Advanced Organic Electronics

DTIC Science & Technology

2011-07-25

printable variants. All have excellent dielectric and insulating properties, a remarkable ability to minimize trapped charge between thin film transistor... trapped charge density, and hence the corresponding OTFT device performance. Under this program we first discovered that OTFT performance is...deep, high- density charge traps must be overcome for efficient FET operation, it has been postulated that in most OFETs, shallow lower-density (~10

Red spruce ecosystem level changes following 14 years of chronic N fertilization

Treesearch

Steven G. McNulty; Johnny Boggs; John D. Aber; Lindsey Rustad; Allison Magill

2005-01-01

In the early 1980s, nitrogen (N) deposition was first postulated as a cause of N saturation and spruce mortality across the northeastern US. In 1988, a series of high elevation spruce-fir forest N addition plots were established on Mt. Ascutney (southeastern) Vermont to test this hypothesis. The paired plots each received, in addition to ambient N deposition, 15.7 kg...

Design and evaluation of an oral multiparticulate system for dual delivery of amoxicillin and Lactobacillus acidophilus.

PubMed

Govender, Mershen; Choonara, Yahya E; van Vuuren, Sandy; Kumar, Pradeep; du Toit, Lisa C; Pillay, Viness

2016-09-01

A delayed-release dual delivery system for amoxicillin and the probiotic Lactobacillus acidophilus was developed and evaluated. Statistical optimization of a cross-linked denatured ovalbumin protective matrix was first synthesized using a Box-Behnken experimental design prior to encapsulation with glyceryl monostereate. The encapsulated ovalbumin matrix was thereafter incorporated with amoxicillin in a gastro-resistant capsule. In vitro characterization and stability analysis of the ovalbumin and encapsulated components were also performed Results: Protection of L. acidophilus probiotic against the bactericidal effects of amoxicillin within the dual formulation was determined. The dual formulation in this study proved effective and provides insight into current microbiome research to identify, classify and use functional healthy bacteria to develop novel probiotic delivery technologies.

Dual Motor-Cognitive Virtual Reality Training Impacts Dual-Task Performance in Freezing of Gait.

PubMed

Killane, Isabelle; Fearon, Conor; Newman, Louise; McDonnell, Conor; Waechter, Saskia M; Sons, Kristian; Lynch, Timothy; Reilly, Richard B

2015-11-01

Freezing of gait (FOG), an episodic gait disturbance characterized by the inability to generate effective stepping, occurs in more than half of Parkinson's disease patients. It is associated with both executive dysfunction and attention and becomes most evident during dual tasking (performing two tasks simultaneously). This study examined the effect of dual motor-cognitive virtual reality training on dual-task performance in FOG. Twenty community dwelling participants with Parkinson's disease (13 with FOG, 7 without FOG) participated in a pre-assessment, eight 20-minute intervention sessions, and a post-assessment. The intervention consisted of a virtual reality maze (DFKI, Germany) through which participants navigated by stepping-in-place on a balance board (Nintendo, Japan) under time pressure. This was combined with a cognitive task (Stroop test), which repeatedly divided participants' attention. The primary outcome measures were pre- and post-intervention differences in motor (stepping time, symmetry, rhythmicity) and cognitive (accuracy, reaction time) performance during single- and dual-tasks. Both assessments consisted of 1) a single cognitive task 2) a single motor task, and 3) a dual motor-cognitive task. Following the intervention, there was significant improvement in dual-task cognitive and motor parameters (stepping time and rhythmicity), dual-task effect for those with FOG and a noteworthy improvement in FOG episodes. These improvements were less significant for those without FOG. This is the first study to show benefit of a dual motor-cognitive approach on dual-task performance in FOG. Advances in such virtual reality interventions for home use could substantially improve the quality of life for patients who experience FOG.

Dual practice in the health sector: review of the evidence

PubMed Central

Ferrinho, Paulo; Van Lerberghe, Wim; Fronteira, Inês; Hipólito, Fátima; Biscaia, André

2004-01-01

This paper reports on income generation practices among civil servants in the health sector, with a particular emphasis on dual practice. It first approaches the subject of public–private overlap. Thereafter it focuses on coping strategies in general and then on dual practice in particular. To compensate for unrealistically low salaries, health workers rely on individual coping strategies. Many clinicians combine salaried, public-sector clinical work with a fee-for-service private clientele. This dual practice is often a means by which health workers try to meet their survival needs, reflecting the inability of health ministries to ensure adequate salaries and working conditions. Dual practice may be considered present in most countries, if not all. Nevertheless, there is surprisingly little hard evidence about the extent to which health workers resort to dual practice, about the balance of economic and other motives for doing so, or about the consequences for the proper use of the scarce public resources dedicated to health. In this paper dual practice is approached from six different perspectives: (1) conceptual, regarding what is meant by dual practice; (2) descriptive, trying to develop a typology of dual practices; (3) quantitative, trying to determine its prevalence; (4) impact on personal income, the health care system and health status; (5) qualitative, looking at the reasons why practitioners so frequently remain in public practice while also working in the private sector and at contextual, personal life, institutional and professional factors that make it easier or more difficult to have dual practices; and (6) possible interventions to deal with dual practice. PMID:15509305

THE METAL CARBONYLS.

PubMed

Blanchard, A A

1941-10-03

When the metal carbonyls were first discovered, their properties were startling because they seemed to violate nearly all the previously recognized generalizations of chemistry. Even to-day the existence of the carbonyls is not particularly emphasized in elementary courses of chemistry because it is rather hard to reconcile them with the first presentations of the generalizations of chemistry. Nevertheless, as the student progresses deeper into the knowledge of chemistry it becomes desirable to include the knowledge of the carbonyls both because they become more comprehensible when viewed in the light of Werner's system of coordination and because they themselves contribute to the comprehension of the Werner theory. As long ago as 1931, Reiff in his discussion of cobalt nitrosyl carbonyl recognized the correlation between the effective atomic number and the volatility of carbonyls. A more recent study of charged Werner coordination complexes, that is, of complex ions, has shown a similar role of the effective atomic number. We are standing on fairly firm ground when we point out the correlation between E.A.N. and the volatility of the carbonyl complexes and the existence of complex ions. Be it noted that we have made no postulates as to the arrangement of the electrons in quantum levels. In the inert gases the outer principal quantum group is supposed always to contain eight electrons. In the carbonyls and other Werner complexes there is no compelling reason to suppose that the electrons in the coordinating layer, be this layer of eight, ten, twelve or sixteen electrons, are not all at the same energy level. Although we have confined our discussion almost exclusively to the property of volatility, the carbonyls are very interesting from the standpoint of several other properties, for example, magnetic susceptibility and dielectric constant. Enthusiasts in the interpretation of such properties try to draw conclusions as to the condition of the electrons, sometimes they become so dogmatic as to seem really.to believe in the actual existence of the condition they postulate. As Professor Smith said, "Theories come and theories go, but facts live on forever." The facts of chemistry are so multitudinous that we would be utterly helpless to use them had we not means of correlating them. Any postulates which reach beneath the surface of the directly observable to give a mechanism to correlate the facts are helpful. But a scientist without a sense of humor is pretty hopeless. Who in his right mind can regard as other than absurd the idea that an electron pair can simultaneously occupy positions in two atom shells to make up the supposedly necessary number in each atom? In fact, is not the electron itself a pretty ridiculous figment of the imagination? To be sure, we recognize the electron as a discrete entity with certain very definite properties, but in the light of comparison with any mechanism within our comprehension is not the electron perfectly impossible? By all means let us use a postulate which allows us to make a useful classification of facts, but never let us lose the sense to see how utterly ridiculous the postulate will look to one who has not like ourselves grown attached to it. We do not expect ever to discover the ultimate reason for things, but we do expect ever to make progress in correlating and classifying the facts which we have already discovered and shall continue to discover. Dogmatic belief in ridiculous postulates retards this progress.

Further theoretical insight into the reaction mechanism of the hepatitis C NS3/NS4A serine protease

NASA Astrophysics Data System (ADS)

Martínez-González, José Ángel; Rodríguez, Alex; Puyuelo, María Pilar; González, Miguel; Martínez, Rodrigo

2015-01-01

The main reactions of the hepatitis C virus NS3/NS4A serine protease are studied using the second-order Møller-Plesset ab initio method and rather large basis sets to correct the previously reported AM1/CHARMM22 potential energy surfaces. The reaction efficiencies measured for the different substrates are explained in terms of the tetrahedral intermediate formation step (the rate-limiting process). The energies of the barrier and the corresponding intermediate are so close that the possibility of a concerted mechanism is open (especially for the NS5A/5B substrate). This is in contrast to the suggested general reaction mechanism of serine proteases, where a two-step mechanism is postulated.

The next 25 years: Industrialization of space - Rationale for planning

NASA Technical Reports Server (NTRS)

Von Puttkamer, J.

1977-01-01

A methodology for planning the industralization of space is discussed. The suggested approach combines the extrapolative ('push') approach, in which alternative futures are projected on the basis of past and current trends and tendencies, with the normative ('pull') view, in which an ideal state in the far future is postulated and policies and decisions are directed toward its attainment. Time-reversed vectors of the future are tied to extrapolated, trend-oriented vectors of the quasi-present to identify common plateaus or stepping stones in technological development. Important steps in the industrialization of space to attain the short-range goals of production of space-derived energy, goods and services and the long-range goal of space colonization are discussed.

Influence of Organic Matter - Mineral Interfacial Reactions on Metal(loid) Speciation and Bioaccessibility

NASA Astrophysics Data System (ADS)

Chorover, J.; Kong, S.; Root, R. A.; Thomas, A.

2015-12-01

Bioaccessibility of contaminant metals in geomedia is often measured on the basis of kinetic release to solution during in vitro reaction with biofluid simulants. We postulate that development of a predictive-mechanistic understanding of bioaccessibility requires knowledge of metal(loid) molecular speciation upon sample introduction, as well as its change over the course of the in vitro reaction. Our results - including data from batch, column, mesocosm and field studies pertaining to arsenic, lead, and zinc contaminated materials - indicate the strong influence of organic matter and associated biological activity on metal(loid) speciation in mine tailings and related model systems. Furthermore, presence/absence of organic matter during bioassays affects the kinetics of metal(loid) release into biofluid simulants through multiple mechanisms.

Molecular mechanisms of maternal vascular dysfunction in preeclampsia.

PubMed

Goulopoulou, Styliani; Davidge, Sandra T

2015-02-01

In preeclampsia, as a heterogeneous syndrome, multiple pathways have been proposed for both the causal as well as the perpetuating factors leading to maternal vascular dysfunction. Postulated mechanisms include imbalance in the bioavailability and activity of endothelium-derived contracting and relaxing factors and oxidative stress. Studies have shown that placenta-derived factors [antiangiogenic factors, microparticles (MPs), cell-free nucleic acids] are released into the maternal circulation and act on the vascular wall to modify the secretory capacity of endothelial cells and alter the responsiveness of vascular smooth muscle cells to constricting and relaxing stimuli. These molecules signal their deleterious effects on the maternal vascular wall via pathways that provide the molecular basis for novel and effective therapeutic interventions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Smelling time: a neural basis for olfactory scene analysis

PubMed Central

Ache, Barry W.; Hein, Andrew M.; Bobkov, Yuriy V.; Principe, Jose C.

2016-01-01

Behavioral evidence from phylogenetically diverse animals and humans suggests that olfaction could be much more involved in interpreting space and time than heretofore imagined by extracting temporal information inherent in the olfactory signal. If this is the case, the olfactory system must have neural mechanisms capable of encoding time at intervals relevant to the turbulent odor world in which many animals live. We review evidence that animals can use populations of rhythmically active or ‘bursting’ olfactory receptor neurons (bORNs) to extract and encode temporal information inherent in natural olfactory signals. We postulate that bORNs represent an unsuspected neural mechanism through which time can be accurately measured, and that ‘smelling time’ completes the requirements for true olfactory scene analysis. PMID:27594700