Microdosimetric Analysis Confirms Similar Biological Effectiveness of External Exposure to Gamma-Rays and Internal Exposure to 137Cs, 134Cs, and 131I

PubMed Central

Sato, Tatsuhiko; Manabe, Kentaro; Hamada, Nobuyuki

2014-01-01

The risk of internal exposure to 137Cs, 134Cs, and 131I is of great public concern after the accident at the Fukushima-Daiichi nuclear power plant. The relative biological effectiveness (RBE, defined herein as effectiveness of internal exposure relative to the external exposure to γ-rays) is occasionally believed to be much greater than unity due to insufficient discussions on the difference of their microdosimetric profiles. We therefore performed a Monte Carlo particle transport simulation in ideally aligned cell systems to calculate the probability densities of absorbed doses in subcellular and intranuclear scales for internal exposures to electrons emitted from 137Cs, 134Cs, and 131I, as well as the external exposure to 662 keV photons. The RBE due to the inhomogeneous radioactive isotope (RI) distribution in subcellular structures and the high ionization density around the particle trajectories was then derived from the calculated microdosimetric probability density. The RBE for the bystander effect was also estimated from the probability density, considering its non-linear dose response. The RBE due to the high ionization density and that for the bystander effect were very close to 1, because the microdosimetric probability densities were nearly identical between the internal exposures and the external exposure from the 662 keV photons. On the other hand, the RBE due to the RI inhomogeneity largely depended on the intranuclear RI concentration and cell size, but their maximum possible RBE was only 1.04 even under conservative assumptions. Thus, it can be concluded from the microdosimetric viewpoint that the risk from internal exposures to 137Cs, 134Cs, and 131I should be nearly equivalent to that of external exposure to γ-rays at the same absorbed dose level, as suggested in the current recommendations of the International Commission on Radiological Protection. PMID:24919099

Health Information Technologies-Academic and Commercial Evaluation (HIT-ACE) methodology: description and application to clinical feedback systems.

PubMed

Lyon, Aaron R; Lewis, Cara C; Melvin, Abigail; Boyd, Meredith; Nicodimos, Semret; Liu, Freda F; Jungbluth, Nathaniel

2016-09-22

Health information technologies (HIT) have become nearly ubiquitous in the contemporary healthcare landscape, but information about HIT development, functionality, and implementation readiness is frequently siloed. Theory-driven methods of compiling, evaluating, and integrating information from the academic and commercial sectors are necessary to guide stakeholder decision-making surrounding HIT adoption and to develop pragmatic HIT research agendas. This article presents the Health Information Technologies-Academic and Commercial Evaluation (HIT-ACE) methodology, a structured, theory-driven method for compiling and evaluating information from multiple sectors. As an example demonstration of the methodology, we apply HIT-ACE to mental and behavioral health measurement feedback systems (MFS). MFS are a specific class of HIT that support the implementation of routine outcome monitoring, an evidence-based practice. HIT-ACE is guided by theories and frameworks related to user-centered design and implementation science. The methodology involves four phases: (1) coding academic and commercial materials, (2) developer/purveyor interviews, (3) linking putative implementation mechanisms to hit capabilities, and (4) experimental testing of capabilities and mechanisms. In the current demonstration, phase 1 included a systematic process to identify MFS in mental and behavioral health using academic literature and commercial websites. Using user-centered design, implementation science, and feedback frameworks, the HIT-ACE coding system was developed, piloted, and used to review each identified system for the presence of 38 capabilities and 18 additional characteristics via a consensus coding process. Bibliometic data were also collected to examine the representation of the systems in the scientific literature. As an example, results are presented for the application of HIT-ACE phase 1 to MFS wherein 49 separate MFS were identified, reflecting a diverse array of characteristics and capabilities. Preliminary findings demonstrate the utility of HIT-ACE to represent the scope and diversity of a given class of HIT beyond what can be identified in the academic literature. Phase 2 data collection is expected to confirm and expand the information presented and phases 3 and 4 will provide more nuanced information about the impact of specific HIT capabilities. In all, HIT-ACE is expected to support adoption decisions and additional HIT development and implementation research.

An analytical model for calculating microdosimetric distributions from heavy ions in nanometer site targets.

PubMed

Czopyk, L; Olko, P

2006-01-01

The analytical model of Xapsos used for calculating microdosimetric spectra is based on the observation that straggling of energy loss can be approximated by a log-normal distribution of energy deposition. The model was applied to calculate microdosimetric spectra in spherical targets of nanometer dimensions from heavy ions at energies between 0.3 and 500 MeV amu(-1). We recalculated the originally assumed 1/E(2) initial delta electrons spectrum by applying the Continuous Slowing Down Approximation for secondary electrons. We also modified the energy deposition from electrons of energy below 100 keV, taking into account the effective path length of the scattered electrons. Results of our model calculations agree favourably with results of Monte Carlo track structure simulations using MOCA-14 for light ions (Z = 1-8) of energy ranging from E = 0.3 to 10.0 MeV amu(-1) as well as with results of Nikjoo for a wall-less proportional counter (Z = 18).

Applying the new HIT results to tokamak and solar plasmas

NASA Astrophysics Data System (ADS)

Jarboe, Thomas; Sutherland, Derek; Hossack, Aaron; Nelson, Brian; Morgan, Kyle; Chris, Hansen; Benedett, Thomas; Everson, Chris; Penna, James

2016-10-01

Understanding sustainment of stable equilibria with helicity injection in HIT-SI has led to a simple picture of several tokamak features. Perturbations cause a viscous-like force on the current that flattens the λ profile, which sustains and stabilizes the equilibrium. An explanation of the mechanism is based on two properties of stable, ideal, two-fluid, magnetized plasma. First, the electron fluid is frozen to magnetic fields and, therefore, current flow is also magnetic field flow. Second, for a stable equilibrium the structure perpendicular to the flux surface resists deformation. Thus toroidal current is from electrons frozen in nested, rotating resilient flux surfaces. Only symmetric flux surfaces allow free differential current flow. Perturbations cause interference of the flux surfaces. Thus, perturbations cause forces that oppose differential electron rotation and forced differential flow produces a symmetrizing force against perturbations and instability. This mechanism can explain the level of field error that spoils tokamak performance and the rate of poloidal flux loss in argon-induced disruptions in DIII-D. This new understanding has led to an explanation of the source of the solar magnetic fields and the power source for the chromosphere, solar wind and corona. Please place in spheromak and FRC section with other HIT posters.

Teachers' Perspectives on Hitting Back in School: Between Inexcusable Violence and Self-Defense

ERIC Educational Resources Information Center

Fleischmann, Amos

2015-01-01

Israeli schools expressly forbid a student to hit back after being attacked. In semistructured interviews, 71 Israeli educators were asked for their views on the hitting-back tactic. The interviews compared their attitude toward hitting back as teachers with their take on the matter as parents. The results, analyzed using grounded theory, show…

Hit discovery of 4-amino-N-(4-(3-(trifluoromethyl)phenoxy)pyrimidin-5-yl)benzamide: A novel EGFR inhibitor from a designed small library.

PubMed

Elkamhawy, Ahmed; Paik, Sora; Hassan, Ahmed H E; Lee, Yong Sup; Roh, Eun Joo

2017-12-01

Searching for hit compounds within the huge chemical space resembles the attempt to find a needle in a haystack. Cheminformatics-guided selection of few representative molecules of a rationally designed virtual combinatorial library is a powerful tool to confront this challenge, speed up hit identification and cut off costs. Herein, this approach has been applied to identify hit compounds with novel scaffolds able to inhibit EGFR kinase. From a generated virtual library, six 4-aryloxy-5-aminopyrimidine scaffold-derived compounds were selected, synthesized and evaluated as hit EGFR inhibitors. 4-Aryloxy-5-benzamidopyrimidines inhibited EGFR with IC 50 1.05-5.37 μM. Cell-based assay of the most potent EGFR inhibitor hit (10ac) confirmed its cytotoxicity against different cancerous cells. In spite of no EGFR, HER2 or VEGFR1 inhibition was elicited by 4-aryloxy-5-(thio)ureidopyrimidine derivatives, cell-based evaluation suggested them as antiproliferative hits acting by other mechanism(s). Molecular docking study provided a plausible explanation of incapability of 4-aryloxy-5-(thio)ureidopyrimidines to inhibit EGFR and suggested a reasonable binding mode of 4-aryloxy-5-benzamidopyrimidines which provides a basis to develop more optimized ligands. Copyright © 2017 Elsevier Inc. All rights reserved.

Cellular uptake of {sup 212}BiOCl by Ehrlich ascites cells: A dosimetric analysis

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

Roeske, J.C.; Whitlock, J.L.; Harper, P.V.

1999-01-01

Bi-212 is an alpha-emitting radionuclide being investigated as a therapeutic agent in the intraperitoneal treatment of micrometastatic ovarian carcinoma. In evaluating a new therapeutic modality, cell-survival studies are often used as a means of quantifying the biological effects of radiation. In this analysis, Ehrlich ascites cells were irradiated under conditions similar to therapy in various concentrations of Bi-212. Immediately following irradiation, a cell survival assay was performed in which cells were plated and colonies were counted after 10--14 days. Both a macrodosimetric and a microdosimetric approach were used in analyzing these data. These models used as input the fraction ofmore » activity within the cell and in solution, the distribution of cell sizes, and the variation of LET along individual alpha-particle tracks. The results indicate that the energy deposited within the nucleus varies significantly among individual cells. There is a small fraction of cell nuclei which receive no hits, while the remaining cells receive energy depositions which can differ significantly from the mean value. These dosimetric parameters are correlated with measured cell survival and will be a useful predictor of outcome for therapeutic doses.« less

High spatial resolution microdosimetry with monolithic ΔE-E detector on 12C beam: Monte Carlo simulations and experiment

NASA Astrophysics Data System (ADS)

Tran, Linh T.; Bolst, David; Guatelli, Susanna; Biasi, Giordano; Fazzi, Alberto; Sagia, Eleni; Prokopovich, Dale A.; Reinhard, Mark I.; Keat, Ying C.; Petasecca, Marco; Lerch, Michael L. F.; Pola, Andrea; Agosteo, Stefano; Matsufuji, Naruhiro; Jackson, Michael; Rosenfeld, Anatoly B.

2018-04-01

Nuclear fragmentation produced in 12C ion therapeutic beams contributes significantly to the Relative Biological Effectiveness (RBE)-weighted dose in the distal edge of the Spread out Bragg Peak (SOBP) and surrounding tissues in out-of-field. Complex mixed radiation field originated by the therapeutic 12C ion beam in a phantom is difficult to measure. This study presents a new method to characterise the radiation field produced in a 12C ion beam using a monolithic ΔE-E telescope which provides the capability to identify the particle components of the mixed radiation field as well as the microdosimetric spectra that allows derivation of the RBE based on a radiobiological model. The response of the monolithic ΔE-E telescope to a 290 MeV/u 12C ion beam at defined positions along the pristine Bragg Peak was studied using the Geant4 Monte Carlo toolkit. The microdosimetric spectra derived from the ΔE stage and the two-dimensional scatter plots of energy deposition in ΔE and E stages of the device in coincidence are presented, as calculated in-field and out-of-field. Partial dose weighted contribution to the microdosimetric spectra from nuclear fragments and recoils, such as 1H, 4He, 3He, 7Li, 9Be and 11B, have been analysed for each position. Comparison of simulation and experimental results are presented and demonstrates that the microdosimetric spectra changes dramatically within 0.5 mm depth increments close to and at the distal edge of the Bragg Peak which is impossible to identify using conventional Tissue Equivalent Proportional Counter (TEPC).

Sci-Thur AM: YIS – 06: A Monte Carlo study of macro- and microscopic dose descriptors and the microdosimetric spread using detailed cellular models

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

Oliver, Patricia; Thomson, Rowan

2016-08-15

Purpose: To develop Monte Carlo models of cell clusters to investigate the relationships between macro- and microscopic dose descriptors, quantify the microdosimetric spread in energy deposition for subcellular targets, and determine how these results depend on the computational model. Methods: Microscopic tissue structure is modelled as clusters of 13 to 150 cells, with cell (nuclear) radii between 5 and 10 microns (2 and 9 microns). Energy imparted per unit mass (specific energy or dose) is scored in the nucleus (D{sub nuc}) and cytoplasm (D{sub cyt}) for incident photon energies from 20 to 370 keV. Dose-to-water (D{sub w,m}) and dose-to-medium (D{submore » m,m}) are compared to D{sub nuc} and D{sub cyt}. Single cells and single nuclear cavities are also simulated. Results: D{sub nuc} and D{sub cyt} are sensitive to the surrounding environment with deviations of up to 13% for a single nucleus/cell compared with a multicellular cluster. These dose descriptors vary with cell and nucleus size by up to 10%. D{sub nuc} and D{sub cyt} differ from D{sub w,m} and D{sub m,m} by up to 32%. The microdosimetric spread is sensitive to whether cells are arranged randomly or in a hexagonal lattice, and whether subcellular compartment sizes are sampled from a normal distribution or are constant throughout the cluster. Conclusions: D{sub nuc} and D{sub cyt} are sensitive to cell morphology, elemental composition and the presence of surrounding cells. The microdosimetric spread was investigated using realistic elemental compositions for the nucleus and cytoplasm, and depends strongly on subcellular compartment size, source energy and dose.« less

Study of microdosimetric energy deposition patterns in tissue-equivalent medium due to low-energy neutron fields using a graphite-walled proportional counter.

PubMed

Waker, A J; Aslam

2011-06-01

To improve radiation protection dosimetry for low-energy neutron fields encountered in nuclear power reactor environments, there is increasing interest in modeling neutron energy deposition in metrological instruments such as tissue-equivalent proportional counters (TEPCs). Along with these computational developments, there is also a need for experimental data with which to benchmark and test the results obtained from the modeling methods developed. The experimental work described in this paper is a study of the energy deposition in tissue-equivalent (TE) medium using an in-house built graphite-walled proportional counter (GPC) filled with TE gas. The GPC is a simple model of a standard TEPC because the response of the counter at these energies is almost entirely due to the neutron interactions in the sensitive volume of the counter. Energy deposition in tissue spheres of diameter 1, 2, 4 and 8 µm was measured in low-energy neutron fields below 500 keV. We have observed a continuously increasing trend in microdosimetric averages with an increase in neutron energy. The values of these averages decrease as we increase the simulated diameter at a given neutron energy. A similar trend for these microdosimetric averages has been observed for standard TEPCs and the Rossi-type, TE, spherical wall-less counter filled with propane-based TE gas in the same energy range. This implies that at the microdosimetric level, in the neutron energy range we employed in this study, the pattern of average energy deposited by starter and insider proton recoil events in the gas is similar to those generated cumulatively by crosser and stopper events originating from the counter wall plus starter and insider recoil events originating in the sensitive volume of a TEPC.

A microdosimetric study of {sup 10}B(n,{alpha}){sup 7}Li and {sup 157}Gd(n,{gamma}) reactions for neutron capture therapy

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

Wang, C.K.C.; Sutton, M.; Evans, T.M.

1999-01-01

This paper presents the microdosimetric analysis for the most interesting cell survival experiment recently performed at the Brookhaven National Laboratory (BNL). In this experiment, the cells were first treated with a gadolinium (Gd) labeled tumor-seeking boronated porphyrin (Gd-BOPP) or with BOPP alone, and then irradiated with thermal neutrons. The resulting cell-survival curves indicate that the {sup 157}Gd(n,{gamma}) reactions are very effective in cell killing. The death of a cell treated with Gd-BOPP was attributed to either the {sup 10}B(n,{alpha}){sup 7}Li reactions or the {sup 157}Gd(n,{gamma}) reactions (or both). However, the quantitative relationship between the two types of reaction and themore » cell-survival fraction was not clear. This paper presents the microdosimetric analysis for the BNL experiment based on the measured experimental parameters, and the results clearly suggest a quantitative relationship between the two types of reaction and the cell survival fraction. The results also suggest new research in gadolinium neutron capture therapy (GdNCT) which may lead to a more practical modality than the boron neutron capture therapy (BNCT) for treating cancers.« less

The multiple-hit pathogenesis of non-alcoholic fatty liver disease (NAFLD).

PubMed

Buzzetti, Elena; Pinzani, Massimo; Tsochatzis, Emmanuel A

2016-08-01

Nonalcoholic fatty liver disease (NAFLD) is increasingly prevalent and represents a growing challenge in terms of prevention and treatment. Despite its high prevalence, only a small minority of affected patients develops inflammation and subsequently fibrosis and chronic liver disease, while most of them only exhibit simple steatosis. In this context, the full understanding of the mechanisms underlying the development of NAFLD and non-alcoholic steatohepatitis (NASH) is of extreme importance; despite advances in this field, knowledge on the pathogenesis of NAFLD is still incomplete. The 'two-hit' hypothesis is now obsolete, as it is inadequate to explain the several molecular and metabolic changes that take place in NAFLD. The "multiple hit" hypothesis considers multiple insults acting together on genetically predisposed subjects to induce NAFLD and provides a more accurate explanation of NAFLD pathogenesis. Such hits include insulin resistance, hormones secreted from the adipose tissue, nutritional factors, gut microbiota and genetic and epigenetic factors. In this article, we review the factors that form this hypothesis. Copyright © 2016 Elsevier Inc. All rights reserved.

Levels of theory and types of theoretical explanation in theoretical physics

NASA Astrophysics Data System (ADS)

Flores, Francisco J.

In Newtonian physics, there is a clear distinction between a 'framework theory', a collection of general physical principles and definitions of physical terms, and theories that describe specific causal interactions such as gravitation, i.e., 'interaction theories'. I argue that this distinction between levels of theory can also be found in the context of Special Relativity and that recognizing it is essential for a philosophical account of how laws are explained in this theory. As a case study, I consider the history of derivations of mass-energy equivalence which shows, I argue, that there are two distinct types of theoretical explanations (i.e., explanations of laws) in physics. One type is best characterized by the 'top-down' account of scientific explanation, while the other is more accurately described by the 'bottom-up' account. What is significant, I argue, is that the type of explanation a law receives depends on whether it is part of the framework theory or part of an interaction theory. The former only receive 'top-down' explanations while the latter can also receive 'bottom- up' explanations. Thus, I argue that current debates regarding 'top-down' vs 'bottom-up' views of scientific explanation can be clarified by recognizing the distinction between two levels of physical theory.

The REH theory of protein and nucleic acid divergence - A retrospective update. [Random Evolutionary Hits

NASA Technical Reports Server (NTRS)

Holmquist, R.

1978-01-01

The random evolutionary hits (REH) theory of evolutionary divergence, originally proposed in 1972, is restated with attention to certain aspects of the theory that have caused confusion. The theory assumes that natural selection and stochastic processes interact and that natural selection restricts those codon sites which may fix mutations. The predicted total number of fixed nucleotide replacements agrees with data for cytochrome c, a-hemoglobin, beta-hemoglobin, and myoglobin. The restatement analyzes the magnitude of possible sources of errors and simplifies calculational methodology by supplying polynomial expressions to replace tables and graphs.

Review of the Microdosimetric Studies for High-Energy Charged Particle Beams Using a Tissue-Equivalent Proportional Counter

NASA Astrophysics Data System (ADS)

Tsuda, Shuichi; Sato, Tatsuhiko; Ogawa, Tatsuhiko; Sasaki, Shinichi

Lineal energy (y) distributions were measured for various types of charged particles such as protons and iron, with kinetic energies of up to 500 MeV/u, via the use of a wall-less tissue-equivalent proportional counter (TEPC). Radial dependencies of y distributions were also experimentally evaluated to investigate the track structures of protons, carbon, and iron beams. This paper reviews a series of measured data using the aforementioned TEPC as well as assesses the systematic verification of a microdosimetric calculation model of a y distribution incorporated into the particle and heavy ion transport code system (PHITS) and associated track structure models.

Progress on the accelerator based SPES-BNCT project at INFN Legnaro

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

Esposito, J.; Colautti, P.; Pisent, A.

2007-02-12

In the framework of an advanced Exotic Ion Beam facility, named SPES (Study and Production of Exotic Species), that will allow a frontier program both in nuclear and interdisciplinary physics, an intense thermal neutron beam facility, devoted to perform Boron Neutron Capture Therapy (BNCT) experimental treatments on skin melanoma tumor, is currently under construction based on the SPES proton driver. A vast radiobiological investigation in vitro and in vivo has started with the new 10B carriers developed. Special microdosimetric detectors have been constructed to properly measure all the BNCT dose components and their qualities. Both microdosimetric and radiobiological measurements aremore » being performed at the new HYTHOR beam shaping assembly at the Enea-Casaccia TAPIRO reactor.« less

Sex Differences in Social Behavior: Are the Social Role and Evolutionary Explanations Compatible?

ERIC Educational Resources Information Center

Archer, John

1996-01-01

Examines competing claims of two explanations of sex differences in social behavior, social role theory, and evolutionary psychology. Findings associated with social role theory are weighed against evolutionary explanations. It is suggested that evolutionary theory better accounts for the overall pattern of sex differences and for their origins.…

Mind and Meaning: Piaget and Vygotsky on Causal Explanation.

ERIC Educational Resources Information Center

Beilin, Harry

1996-01-01

Piaget's theory has been characterized as descriptive and not explanatory, not qualifying as causal explanation. Piaget was consistent in showing how his theory was both explanatory and causal. Vygotsky also endorsed causal-genetic explanation but, on the basis of knowledge of only Piaget's earliest works, he claimed that Piaget's theory was not…

Estimation of relative biological effectiveness for boron neutron capture therapy using the PHITS code coupled with a microdosimetric kinetic model

PubMed Central

Horiguchi, Hironori; Sato, Tatsuhiko; Kumada, Hiroaki; Yamamoto, Tetsuya; Sakae, Takeji

2015-01-01

Abstract The absorbed doses deposited by boron neutron capture therapy (BNCT) can be categorized into four components: α and 7Li particles from the 10B(n, α)7Li reaction, 0.54-MeV protons from the 14N(n, p)14C reaction, the recoiled protons from the 1H(n, n) 1H reaction, and photons from the neutron beam and 1H(n, γ)2H reaction. For evaluating the irradiation effect in tumors and the surrounding normal tissues in BNCT, it is of great importance to estimate the relative biological effectiveness (RBE) for each dose component in the same framework. We have, therefore, established a new method for estimating the RBE of all BNCT dose components on the basis of the microdosimetric kinetic model. This method employs the probability density of lineal energy, y, in a subcellular structure as the index for expressing RBE, which can be calculated using the microdosimetric function implemented in the particle transport simulation code (PHITS). The accuracy of this method was tested by comparing the calculated RBE values with corresponding measured data in a water phantom irradiated with an epithermal neutron beam. The calculation technique developed in this study will be useful for biological dose estimation in treatment planning for BNCT. PMID:25428243

Development of a multi-element microdosimetric detector based on a thick gas electron multiplier

NASA Astrophysics Data System (ADS)

Anjomani, Z.; Hanu, A. R.; Prestwich, W. V.; Byun, S. H.

2017-03-01

A prototype multi-element gaseous microdosimetric detector was developed using the Thick Gas Electron Multiplier (THGEM) technique. The detector aims at measuring neutron and gamma-ray dose rates for weak neutron-gamma radiation fields. The multi-element design was employed to increase the neutron detection efficiency. The prototype THGEM multi-element detector consists of three layers of tissue equivalent plastic hexagons and each layer houses a hexagonal array of seven cylindrical gas cavity elements with equal heights and diameters of 17 mm. The final detector structure incorporates 21 gaseous volumes. Owing to the absence of wire electrodes, the THGEM multi-element detector offers flexible and convenient fabrication. The detector responses to neutron and gamma-ray were investigated using the McMaster Tandetron 7Li(p,n) neutron source. The dosimetric performance of the detector is presented in contrast to the response of a commercial tissue equivalent proportional counter. Compared to the standard TEPC response, the detector gave a consistent microdosimetric response with an average discrepancy of 8 % in measured neutron absorbed dose. An improvement of a factor of 3.0 in neutron detection efficiency has been accomplished with only a small degradation in energy resolution. However, its low energy cut off is about 6 keV/μm, which is not sufficient to measure the gamma-ray dose. This problem will be addressed by increasing the electron multiplication gain using double THGEM layers.

Theoretical explanations for maintenance of behaviour change: a systematic review of behaviour theories.

PubMed

Kwasnicka, Dominika; Dombrowski, Stephan U; White, Martin; Sniehotta, Falko

2016-09-01

Behaviour change interventions are effective in supporting individuals in achieving temporary behaviour change. Behaviour change maintenance, however, is rarely attained. The aim of this review was to identify and synthesise current theoretical explanations for behaviour change maintenance to inform future research and practice. Potentially relevant theories were identified through systematic searches of electronic databases (Ovid MEDLINE, Embase, PsycINFO). In addition, an existing database of 80 theories was searched, and 25 theory experts were consulted. Theories were included if they formulated hypotheses about behaviour change maintenance. Included theories were synthesised thematically to ascertain overarching explanations for behaviour change maintenance. Initial theoretical themes were cross-validated. One hundred and seventeen behaviour theories were identified, of which 100 met the inclusion criteria. Five overarching, interconnected themes representing theoretical explanations for behaviour change maintenance emerged. Theoretical explanations of behaviour change maintenance focus on the differential nature and role of motives, self-regulation, resources (psychological and physical), habits, and environmental and social influences from initiation to maintenance. There are distinct patterns of theoretical explanations for behaviour change and for behaviour change maintenance. The findings from this review can guide the development and evaluation of interventions promoting maintenance of health behaviours and help in the development of an integrated theory of behaviour change maintenance.

Theoretical explanations for maintenance of behaviour change: a systematic review of behaviour theories

PubMed Central

Kwasnicka, Dominika; Dombrowski, Stephan U; White, Martin; Sniehotta, Falko

2016-01-01

ABSTRACT Background: Behaviour change interventions are effective in supporting individuals in achieving temporary behaviour change. Behaviour change maintenance, however, is rarely attained. The aim of this review was to identify and synthesise current theoretical explanations for behaviour change maintenance to inform future research and practice. Methods: Potentially relevant theories were identified through systematic searches of electronic databases (Ovid MEDLINE, Embase, PsycINFO). In addition, an existing database of 80 theories was searched, and 25 theory experts were consulted. Theories were included if they formulated hypotheses about behaviour change maintenance. Included theories were synthesised thematically to ascertain overarching explanations for behaviour change maintenance. Initial theoretical themes were cross-validated. Findings: One hundred and seventeen behaviour theories were identified, of which 100 met the inclusion criteria. Five overarching, interconnected themes representing theoretical explanations for behaviour change maintenance emerged. Theoretical explanations of behaviour change maintenance focus on the differential nature and role of motives, self-regulation, resources (psychological and physical), habits, and environmental and social influences from initiation to maintenance. Discussion: There are distinct patterns of theoretical explanations for behaviour change and for behaviour change maintenance. The findings from this review can guide the development and evaluation of interventions promoting maintenance of health behaviours and help in the development of an integrated theory of behaviour change maintenance. PMID:26854092

Oncogenic transformation in C3H10T1/2 cells by low-energy neutrons.

PubMed

Miller, R C; Marino, S A; Napoli, J; Shah, H; Hall, E J; Geard, C R; Brenner, D J

2000-03-01

Occupational exposure to neutrons typically includes significant doses of low-energy neutrons, with energies below 100 keV. In addition, the normal-tissue dose from boron neutron capture therapy will largely be from low-energy neutrons. Microdosimetric theory predicts decreasing biological effectiveness for neutrons with energies below about 350 keV compared with that for higher-energy neutrons; based on such considerations, and limited biological data, the current radiation weighting factor (quality factor) for neutrons with energies from 10 keV to 100 keV is less than that for higher-energy neutrons. By contrast, some reports have suggested that the biological effectiveness of low-energy neutrons is similar to that of fast neutrons. The purpose of the current work is to assess the relative biological effectiveness of low-energy neutrons for an endpoint of relevance to carcinogenesis: in vitro oncogenic transformation. Oncogenic transformation induction frequencies were determined for C3H10T1/2 cells exposed to two low-energy neutron beams, respectively, with dose-averaged energies of 40 and 70 keV, and the results were compared with those for higher-energy neutrons and X-rays. These results for oncogenic transformation provide evidence for a significant decrease in biological effectiveness for 40 keV neutrons compared with 350 keV neutrons. The 70 keV neutrons were intermediate in effectiveness between the 70 and 350 keV beams. A decrease in biological effectiveness for low-energy neutrons is in agreement with most (but not all) earlier biological studies, as well as microdosimetric considerations. The results for oncogenic transformation were consistent with the currently recommended decreased values for low-energy neutron radiation weighting factors compared with fast neutrons.

Estimation of relative biological effectiveness for boron neutron capture therapy using the PHITS code coupled with a microdosimetric kinetic model.

PubMed

Horiguchi, Hironori; Sato, Tatsuhiko; Kumada, Hiroaki; Yamamoto, Tetsuya; Sakae, Takeji

2015-03-01

The absorbed doses deposited by boron neutron capture therapy (BNCT) can be categorized into four components: α and (7)Li particles from the (10)B(n, α)(7)Li reaction, 0.54-MeV protons from the (14)N(n, p)(14)C reaction, the recoiled protons from the (1)H(n, n) (1)H reaction, and photons from the neutron beam and (1)H(n, γ)(2)H reaction. For evaluating the irradiation effect in tumors and the surrounding normal tissues in BNCT, it is of great importance to estimate the relative biological effectiveness (RBE) for each dose component in the same framework. We have, therefore, established a new method for estimating the RBE of all BNCT dose components on the basis of the microdosimetric kinetic model. This method employs the probability density of lineal energy, y, in a subcellular structure as the index for expressing RBE, which can be calculated using the microdosimetric function implemented in the particle transport simulation code (PHITS). The accuracy of this method was tested by comparing the calculated RBE values with corresponding measured data in a water phantom irradiated with an epithermal neutron beam. The calculation technique developed in this study will be useful for biological dose estimation in treatment planning for BNCT. © The Author 2014. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

An Explanation of the Relationship between Instructor Humor and Student Learning: Instructional Humor Processing Theory

ERIC Educational Resources Information Center

Wanzer, Melissa B.; Frymier, Ann B.; Irwin, Jeffrey

2010-01-01

This paper proposes the Instructional Humor Processing Theory (IHPT), a theory that incorporates elements of incongruity-resolution theory, disposition theory, and the elaboration likelihood model (ELM) of persuasion. IHPT is proposed and offered as an explanation for why some types of instructor-generated humor result in increased student…

The validation of Huffaz Intelligence Test (HIT)

NASA Astrophysics Data System (ADS)

Rahim, Mohd Azrin Mohammad; Ahmad, Tahir; Awang, Siti Rahmah; Safar, Ajmain

2017-08-01

In general, a hafiz who can memorize the Quran has many specialties especially in respect to their academic performances. In this study, the theory of multiple intelligences introduced by Howard Gardner is embedded in a developed psychometric instrument, namely Huffaz Intelligence Test (HIT). This paper presents the validation and the reliability of HIT of some tahfiz students in Malaysia Islamic schools. A pilot study was conducted involving 87 huffaz who were randomly selected to answer the items in HIT. The analysis method used includes Partial Least Square (PLS) on reliability, convergence and discriminant validation. The study has validated nine intelligences. The findings also indicated that the composite reliabilities for the nine types of intelligences are greater than 0.8. Thus, the HIT is a valid and reliable instrument to measure the multiple intelligences among huffaz.

A highly optimized vectorized code for Monte Carlo simulations of SU(3) lattice gauge theories

NASA Technical Reports Server (NTRS)

Barkai, D.; Moriarty, K. J. M.; Rebbi, C.

1984-01-01

New methods are introduced for improving the performance of the vectorized Monte Carlo SU(3) lattice gauge theory algorithm using the CDC CYBER 205. Structure, algorithm and programming considerations are discussed. The performance achieved for a 16(4) lattice on a 2-pipe system may be phrased in terms of the link update time or overall MFLOPS rates. For 32-bit arithmetic, it is 36.3 microsecond/link for 8 hits per iteration (40.9 microsecond for 10 hits) or 101.5 MFLOPS.

Causal-Explanatory Pluralism: How Intentions, Functions, and Mechanisms Influence Causal Ascriptions

ERIC Educational Resources Information Center

Lombrozo, Tania

2010-01-01

Both philosophers and psychologists have argued for the existence of distinct kinds of explanations, including teleological explanations that cite functions or goals, and mechanistic explanations that cite causal mechanisms. Theories of causation, in contrast, have generally been unitary, with dominant theories focusing either on counterfactual…

Positive Side Effects in the Treatment of SIB Using the Self-Injurious Behavior Inhibiting System (SIBIS): Implications for Operant and Biochemical Explanations of SIB.

ERIC Educational Resources Information Center

Linscheid, Thomas R.; And Others

1994-01-01

The rate of self-injurious head hitting in an eight-year old with severe/profound mental retardation was reduced using contingent electric shock delivered via the Self Injurious Behavior Inhibiting System. An improved affective state and increased interaction with the environment were documented. Treatment gains were maintained at one-year…

Health Informatics and Technology for Integrated Elderly Care in the Context of Hong Kong: A Case Study.

PubMed

Chau, Cheuk Wing; Leung, Eman

2017-01-01

The aging population creates tremendous pressure to healthcare. To resolve, scholars recognized the solution to this challenge is integrated care. To facilitate integrated care, health information technologies (HIT) is a critical enabler. This paper will first review how technology enhanced integrated care, and review on the existing literatures in system effective use and the three key external factors that enable HIT implementation. Applying Burton-Jones and Volkoff's contextualized theories of effective use of HIT to understand the role of health informatics and technology in the unique context of Hong Kong, we have conducted a case study research to identify the levers for improving HK integration of care through HIT.

Fifteen symposia on microdosimetry: implications for modern particle-beam cancer radiotherapy.

PubMed

Wambersie, A; Menzel, H; Gueulette, J; Pihet, P

2015-09-01

The objective of microdosimetry was, and still is, to identify physical descriptions of the initial physical processes of ionising radiation interacting with biological matter which correlate with observed radiobiological effects with a view to improve the understanding of radiobiological mechanisms and effects. The introduction of therapy with particles starting with fast neutrons followed by negative pions, protons and light ions necessitated the application of biological weighting factors for absorbed dose in order to account for differences of the relative biological effectiveness (RBE). Dedicated radiobiological experiments in therapy beams with mammalian cells and with laboratory animals provided sets of RBE values which are used to evaluate empirical 'clinical RBE values'. The combination of such experiments with microdosimetric measurements in identical conditions offered the possibility to establish semi-empirical relationships between microdosimetric parameters and results of RBE studies. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

MICRODOSIMETRIC MEASUREMENT OF SECONDARY RADIATION IN THE PASSIVE SCATTERED PROTON THERAPY ROOM OF iTHEMBA LABS USING A TISSUE-EQUIVALENT PROPORTIONAL COUNTER.

PubMed

Chiriotti, S; Parisi, A; Vanhavere, F; De Saint-Hubert, M; Vandevoorde, C; Slabbert, J; Beukes, P; de Kock, E; Symons, J

2018-04-13

Measurements of the dose equivalent at different distances from the isocenter of the proton therapy center at iThemba LABS were previously performed with a tissue-equivalent proportional counter (TEPC). These measurements showed that the scattered radiation levels were one or two orders of magnitude higher in comparison to other passive scattering delivery systems. In order to reduce these radiation levels, additional shielding was installed shortly after the measurements were done. Therefore, the aim of this work is to quantify and assess the reduction of the secondary doses delivered in the proton therapy room at iThemba LABS after the installation of the additional shielding. This has been performed by measuring microdosimetric spectra with a TEPC at 11 locations around the isocenter when a clinical modulated beam of 200 MeV proton was impinging onto a water phantom placed at the isocenter.

Enhancing Student Explanations of Evolution: Comparing Elaborating and Competing Theory Prompts

ERIC Educational Resources Information Center

Donnelly, Dermot F.; Namdar, Bahadir; Vitale, Jonathan M.; Lai, Kevin; Linn, Marcia C.

2016-01-01

In this study, we explore how two different prompt types within an online computer-based inquiry learning environment enhance 392 7th grade students' explanations of evolution with three teachers. In the "elaborating" prompt condition, students are prompted to write explanations that support the accepted theory of evolution. In the…

Health Information Technology Systems profoundly impact users: a case study in a dental school.

PubMed

Hill, Heather K; Stewart, Denice C L; Ash, Joan S

2010-04-01

The purpose of this study was to increase our understanding of the impact of Health Information Technology Systems (HITS) on dental school users when the systems are integrated into chair-side patient care. We used qualitative research methods, including interviews, focus groups, and observations, to capture the experiences of HITS users at a single institution. Users included administrators, clinical faculty members, predoctoral students, support staff, and residents. The data were analyzed using a grounded theory approach, and nine themes emerged: 1) HITS benefits were disproportionate among users; 2) communicating about the HITS was challenging; 3) users experienced a range of strong emotions; 4) the instructor persona diminished; 5) there were shifts in the school's power structure; 6) allocation of end-users' time shifted; 7) the training and support needs of end-users were significant; 8) perceived lack of HITS usability made documentation cumbersome for clinicians; and 9) clinicians' workflow was disrupted. HITS integration into patient care impacts the work of all system users, especially end-users. The themes highlight areas of potential concern for implementers and users in integrating a HITS into patient care.

On the nature of explanation: A PDP approach

NASA Astrophysics Data System (ADS)

Churchland, Paul M.

1990-06-01

Neural network models of sensory processing and associative memory provide the resources for a new theory of what explanatory understanding consists in. That theory finds the theoretically important factors to reside not at the level of propositions and the relations between them, but at the level of the activation patterns across large populations of neurons. The theory portrays explanatory understanding, perceptual recognition, and abductive inference as being different instances of the same more general sort of cognitive achievement, viz. prototype activation. It thus effects a unification of the theories of explanation, perception, and ampliative inference. It also finds systematic unity in the wide diversity of types of explanation (causal, functional, mathematical, intentional, reductive, etc.), a chronic problem for theories of explanation in the logico-linguistic tradition. Finally, it is free of the many defects, both logical and psychological, that plague models in that older tradition.

The effect of microdosimetric 12C6+ heavy ion irradiation and Mg2+ on canthaxanthin production in a novel strain of Dietzia natronolimnaea.

PubMed

Zhou, Xiang; Xie, Jia-Rong; Tao, Lei; Xin, Zhi-Jun; Zhao, Feng-Wu; Lu, Xi-Hong; Zhao, Mei-Rong; Wang, Liang; Liang, Jian-Ping

2013-09-28

Dietzia natronolimnaea is one of the most important bacterial bioresources for high efficiency canthaxanthin production. It produces the robust and stable pigment canthaxanthin, which is of special interest for the development of integrated biorefineries. Mutagenesis employing 12C6+ irradiation is a novel technique commonly used to improve microorganism productivity. This study presents a promising route to obtaining the highest feasible levels of biomass dry weight (BDW), and total canthaxanthin by using a microdosimetric model of 12C6+ irradiation mutation in combination with the optimization of nutrient medium components. This work characterized the rate of both lethal and non-lethal dose mutations for 12C6+ irradiation and the microdosimetric kinetic model using the model organism, D. natronolimnaea svgcc1.2736. Irradiation with 12C6+ ions resulted in enhanced production of canthaxanthin, and is therefore an effective method for strain improvement of D. natronolimnaea svgcc1.2736. Based on these results an optimal dose of 0.5-4.5 Gy, Linear energy transfer (LET) of 80 keV μm-1and energy of 60 MeV u-1 for 12C6+ irradiation are ideal for optimum and specific production of canthaxanthin in the bacterium. Second-order empirical calculations displaying high R-squared (0.996) values between the responses and independent variables were derived from validation experiments using response surface methodology. The highest canthaxanthin yield (8.14 mg) was obtained with an optimized growth medium containing 21.5 g L-1 D-glucose, 23.5 g L-1 mannose and 25 ppm Mg2+ in 1 L with an irradiation dose of 4.5 Gy. The microdosimetric 12C6+ irradiation model was an effective mutagenic technique for the strain improvement of D. natronolimnaea svgcc1.2736 specifically for enhanced canthaxanthin production. At the very least, random mutagenesis methods using 12C6+ions can be used as a first step in a combined approach with long-term continuous fermentation processes. Central composite design-response surface methodologies (CCD-RSM) were carried out to optimize the conditions for canthaxanthin yield. It was discovered D-glucose, Mg2+ and mannose have significant influence on canthaxanthin biosynthesis and growth of the mutant strain.

Theory-based explanation as intervention.

PubMed

Weisman, Kara; Markman, Ellen M

2017-10-01

Cogent explanations are an indispensable means of providing new information and an essential component of effective education. Beyond this, we argue that there is tremendous untapped potential in using explanations to motivate behavior change. In this article we focus on health interventions. We review four case studies that used carefully tailored explanations to address gaps and misconceptions in people's intuitive theories, providing participants with a conceptual framework for understanding how and why some recommended behavior is an effective way of achieving a health goal. These case studies targeted a variety of health-promoting behaviors: (1) children washing their hands to prevent viral epidemics; (2) parents vaccinating their children to stem the resurgence of infectious diseases; (3) adults completing the full course of an antibiotic prescription to reduce antibiotic resistance; and (4) children eating a variety of healthy foods to improve unhealthy diets. Simply telling people to engage in these behaviors has been largely ineffective-if anything, concern about these issues is mounting. But in each case, teaching participants coherent explanatory frameworks for understanding health recommendations has shown great promise, with such theory-based explanations outperforming state-of-the-art interventions from national health authorities. We contrast theory-based explanations both with simply listing facts, information, and advice and with providing a full-blown educational curriculum, and argue for providing the minimum amount of information required to understand the causal link between a target behavior and a health outcome. We argue that such theory-based explanations lend people the motivation and confidence to act on their new understanding.

Phonological neighborhood and word frequency effects on the stuttered disfluencies of children who stutter: comments on Anderson (2007).

PubMed

Howell, Peter

2010-10-01

This letter comments on a study by Anderson (2007) that compared the effects of word frequency, neighborhood density, and phonological neighborhood frequency on part-word repetitions, prolongations, and single-syllable word repetitions produced by children who stutter. Anderson discussed her results with respect to 2 theories about stuttering: the covert repair hypothesis and execution planning (EXPLAN) theory. Her remarks about EXPLAN theory are examined. Anderson considered that EXPLAN does not predict the relationship between word and neighborhood frequency and stuttering for part-word repetitions and prolongations (she considered that EXPLAN predicts that stuttering occurs on simple words for children). The actual predictions that EXPLAN makes are upheld by her results. She also considered that EXPLAN cannot account for why stuttering is affected by the same variables that lead to speech errors, and it is shown that this is incorrect. The effects of word frequency, neighborhood density, and phonological neighborhood frequency on part-word repetitions, prolongations, and single-syllable word repetitions reported by Anderson (2007) are consistent with the predictions of the EXPLAN model.

Derivation of dynamo current drive in a closed-current volume and stable current sustainment in the HIT-SI experiment

DOE PAGES

Hossack, A. C.; Sutherland, D. A.; Jarboe, T. R.

2017-02-01

A derivation is given showing that the current inside a closed-current volume can be sustained against resistive dissipation by appropriately phased magnetic perturbations. Imposed-dynamo current drive (IDCD) theory is used to predict the toroidal current evolution in the HIT-SI experiment as a function of magnetic fluctuations at the edge. Analysis of magnetic fields from a HIT-SI discharge shows that the injector-imposed fluctuations are sufficient to sustain the measured toroidal current without instabilities whereas the small, plasma-generated magnetic fluctuations are not sufficiently large to sustain the current.

Derivation of dynamo current drive in a closed-current volume and stable current sustainment in the HIT-SI experiment

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

Hossack, A. C.; Sutherland, D. A.; Jarboe, T. R.

A derivation is given showing that the current inside a closed-current volume can be sustained against resistive dissipation by appropriately phased magnetic perturbations. Imposed-dynamo current drive (IDCD) theory is used to predict the toroidal current evolution in the HIT-SI experiment as a function of magnetic fluctuations at the edge. Analysis of magnetic fields from a HIT-SI discharge shows that the injector-imposed fluctuations are sufficient to sustain the measured toroidal current without instabilities whereas the small, plasma-generated magnetic fluctuations are not sufficiently large to sustain the current.

Children Balance Theories and Evidence in Exploration, Explanation, and Learning

ERIC Educational Resources Information Center

Bonawitz, Elizabeth Baraff; van Schijndel, Tessa J. P.; Friel, Daniel; Schulz, Laura

2012-01-01

We look at the effect of evidence and prior beliefs on exploration, explanation and learning. In Experiment 1, we tested children both with and without differential prior beliefs about balance relationships (Center Theorists, mean: 82 months; Mass Theorists, mean: 89 months; No Theory children, mean: 62 months). Center and Mass Theory children who…

Theory, explanation, and a third generation of theoretical development in social gerontology.

PubMed

Bengtson, V L; Burgess, E O; Parrott, T M

1997-03-01

Efforts at cumulative knowledge building in social gerontology have been lax, judging from research articles published in journals between 1990 and 1994. Too little attention has been paid to the cumulative development of theory; readers are left with many empirical generalizations but underdeveloped explanations by which to interpret findings and build upon them in subsequent research. To assist future theory development in social gerontology, we review seven theoretical perspectives referenced most frequently in recent journals: (1) social constructionist, (2) social exchange, (3) life course, (4) feminist, (5) age stratification (age and society), (6) political economy of aging, and (7) critical theory. We suggest that, taken together, these represent a "third generation" of explanation in social gerontology, noting their debt to older and more established traditions in social science theory. We argue that authors and journal reviewers should place more emphasis on theory development - which means, most simply, the construction of explicit explanations in accounting for empirical findings - if knowledge development about social aspects of aging is to be cumulative, systematic, and incremental.

To justify or excuse?: A meta-analytic review of the effects of explanations.

PubMed

Shaw, John C; Wild, Eric; Colquitt, Jason A

2003-06-01

The authors used R. Folger and R. Cropanzano's (1998, 2001) fairness theory to derive predictions about the effects of explanation provision and explanation adequacy on justice judgments and cooperation, retaliation, and withdrawal responses. The authors also used the theory to identify potential moderators of those effects, including the type of explanation (justification vs. excuse), outcome favorability, and study context. The authors' predictions were tested by using meta-analyses of 54 independent samples. The results showed strong effects of explanations on both the justice and response variables. Moreover, explanations were more beneficial when they took the form of excuses rather than justifications, when they were given after unfavorable outcomes, and when they were given in contexts with instrumental, relational, and moral implications.

Space Junk Norms: US Advantages in Creating a Debris Reducing Outer Space Norm

DTIC Science & Technology

2011-05-01

and White Knight ,” http://www.scaled.com/projects/tierone/ (accessed 25 March 2011). 26 Mike Moore argues that the nearest global competitor to the...formation of norms. 27 For an explanation of the US 2008 ASAT test, see Jamie McIntyre...the Space Age. Baltimore: Johns Hopkins University Press, 1997. McIntyre, Jamie , Suzanne Malveaux and Miles O’Brien. “Navy Missile Hits Dying Spy

Local Choices: Rationality and the Contextuality of Decision-Making

PubMed Central

Vlaev, Ivo

2018-01-01

Rational explanation is ubiquitous in psychology and social sciences, ranging from rational analysis, expectancy-value theories, ideal observer models, mental logic to probabilistic frameworks, rational choice theory, and informal “folk psychological” explanation. However, rational explanation appears to be challenged by apparently systematic irrationality observed in psychological experiments, especially in the field of judgement and decision-making (JDM). Here, it is proposed that the experimental results require not that rational explanation should be rejected, but that rational explanation is local, i.e., within a context. Thus, rational models need to be supplemented with a theory of contextual shifts. We review evidence in JDM that patterns of choices are often consistent within contexts, but unstable between contexts. We also demonstrate that for a limited, though reasonably broad, class of decision-making domains, recent theoretical models can be viewed as providing theories of contextual shifts. It is argued that one particular significant source of global inconsistency arises from a cognitive inability to represent absolute magnitudes, whether for perceptual variables, utilities, payoffs, or probabilities. This overall argument provides a fresh perspective on the scope and limits of human rationality. PMID:29301289

Local Choices: Rationality and the Contextuality of Decision-Making.

PubMed

Vlaev, Ivo

2018-01-02

Rational explanation is ubiquitous in psychology and social sciences, ranging from rational analysis, expectancy-value theories, ideal observer models, mental logic to probabilistic frameworks, rational choice theory, and informal "folk psychological" explanation. However, rational explanation appears to be challenged by apparently systematic irrationality observed in psychological experiments, especially in the field of judgement and decision-making (JDM). Here, it is proposed that the experimental results require not that rational explanation should be rejected, but that rational explanation is local , i.e., within a context. Thus, rational models need to be supplemented with a theory of contextual shifts. We review evidence in JDM that patterns of choices are often consistent within contexts, but unstable between contexts. We also demonstrate that for a limited, though reasonably broad, class of decision-making domains, recent theoretical models can be viewed as providing theories of contextual shifts. It is argued that one particular significant source of global inconsistency arises from a cognitive inability to represent absolute magnitudes, whether for perceptual variables, utilities, payoffs, or probabilities. This overall argument provides a fresh perspective on the scope and limits of human rationality.

Two Methods for Efficient Solution of the Hitting-Set Problem

NASA Technical Reports Server (NTRS)

Vatan, Farrokh; Fijany, Amir

2005-01-01

A paper addresses much of the same subject matter as that of Fast Algorithms for Model-Based Diagnosis (NPO-30582), which appears elsewhere in this issue of NASA Tech Briefs. However, in the paper, the emphasis is more on the hitting-set problem (also known as the transversal problem), which is well known among experts in combinatorics. The authors primary interest in the hitting-set problem lies in its connection to the diagnosis problem: it is a theorem of model-based diagnosis that in the set-theory representation of the components of a system, the minimal diagnoses of a system are the minimal hitting sets of the system. In the paper, the hitting-set problem (and, hence, the diagnosis problem) is translated from a combinatorial to a computational problem by mapping it onto the Boolean satisfiability and integer- programming problems. The paper goes on to describe developments nearly identical to those summarized in the cited companion NASA Tech Briefs article, including the utilization of Boolean-satisfiability and integer- programming techniques to reduce the computation time and/or memory needed to solve the hitting-set problem.

Factors influencing nurses' attitudes towards healthcare information technology.

PubMed

Huryk, Laurie A

2010-07-01

This literature review examines the current trend in nurses' attitudes toward healthcare information technology (HIT). HIT implementation and expansion are at the core of global efforts to improve healthcare quality and patient safety. As a large portion of the healthcare workforce, nurses' attitudes towards HIT are likely to have a major impact on the electronic health record (EHR) implementation process. A search of PubMed, CINAHL and Medline databases produced 1930 combined hits. Returned articles were scanned for relevancy and applicability. Thirteen articles met all criteria and were subsequently reviewed in their entirety. In accordance with two change theories, if HIT implementation projects are to be successful, nurses must recognize that incorporating EHRs into their daily practice is beneficial to patient outcomes. Overall, the attitudes of nurses toward HIT are positive. Increased computer experience is the main demographic indicator for positive attitudes. The most common detractors are poor system design, system slowdown and system downtime. Nurses are also fearful that the use of technology will dehumanize patient care. Involving nurses in system design is likely to improve post-implementation satisfaction. Creating a positive, supportive atmosphere appears to be instrumental to sustainability.

Construct and face validity of a new model for the three-hit theory of depression using PACAP mutant mice on CD1 background.

PubMed

Farkas, József; Kovács, László Á; Gáspár, László; Nafz, Anna; Gaszner, Tamás; Ujvári, Balázs; Kormos, Viktória; Csernus, Valér; Hashimoto, Hitoshi; Reglődi, Dóra; Gaszner, Balázs

2017-06-23

Major depression is a common cause of chronic disability. Despite decades of efforts, no equivocally accepted animal model is available for studying depression. We tested the validity of a new model based on the three-hit concept of vulnerability and resilience. Genetic predisposition (hit 1, mutation of pituitary adenylate cyclase-activating polypeptide, PACAP gene), early-life adversity (hit 2, 180-min maternal deprivation, MD180) and chronic variable mild stress (hit 3, CVMS) were combined. Physical, endocrinological, behavioral and functional morphological tools were used to validate the model. Body- and adrenal weight changes as well as corticosterone titers proved that CVMS was effective. Forced swim test indicated increased depression in CVMS PACAP heterozygous (Hz) mice with MD180 history, accompanied by elevated anxiety level in marble burying test. Corticotropin-releasing factor neurons in the oval division of the bed nucleus of the stria terminalis showed increased FosB expression, which was refractive to CVMS exposure in wild-type and Hz mice. Urocortin1 neurons became over-active in CMVS-exposed PACAP knock out (KO) mice with MD180 history, suggesting the contribution of centrally projecting Edinger-Westphal nucleus to the reduced depression and anxiety level of stressed KO mice. Serotoninergic neurons of the dorsal raphe nucleus lost their adaptation ability to CVMS in MD180 mice. In conclusion, the construct and face validity criteria suggest that MD180 PACAP HZ mice on CD1 background upon CVMS may be used as a reliable model for the three-hit theory. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Validation of the physical and RBE-weighted dose estimator based on PHITS coupled with a microdosimetric kinetic model for proton therapy.

PubMed

Takada, Kenta; Sato, Tatsuhiko; Kumada, Hiroaki; Koketsu, Junichi; Takei, Hideyuki; Sakurai, Hideyuki; Sakae, Takeji

2018-01-01

The microdosimetric kinetic model (MKM) is widely used for estimating relative biological effectiveness (RBE)-weighted doses for various radiotherapies because it can determine the surviving fraction of irradiated cells based on only the lineal energy distribution, and it is independent of the radiation type and ion species. However, the applicability of the method to proton therapy has not yet been investigated thoroughly. In this study, we validated the RBE-weighted dose calculated by the MKM in tandem with the Monte Carlo code PHITS for proton therapy by considering the complete simulation geometry of the clinical proton beam line. The physical dose, lineal energy distribution, and RBE-weighted dose for a 155 MeV mono-energetic and spread-out Bragg peak (SOBP) beam of 60 mm width were evaluated. In estimating the physical dose, the calculated depth dose distribution by irradiating the mono-energetic beam using PHITS was consistent with the data measured by a diode detector. A maximum difference of 3.1% in the depth distribution was observed for the SOBP beam. In the RBE-weighted dose validation, the calculated lineal energy distributions generally agreed well with the published measurement data. The calculated and measured RBE-weighted doses were in excellent agreement, except at the Bragg peak region of the mono-energetic beam, where the calculation overestimated the measured data by ~15%. This research has provided a computational microdosimetric approach based on a combination of PHITS and MKM for typical clinical proton beams. The developed RBE-estimator function has potential application in the treatment planning system for various radiotherapies. © The Author 2017. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Validation of the physical and RBE-weighted dose estimator based on PHITS coupled with a microdosimetric kinetic model for proton therapy

PubMed Central

Sato, Tatsuhiko; Kumada, Hiroaki; Koketsu, Junichi; Takei, Hideyuki; Sakurai, Hideyuki; Sakae, Takeji

2018-01-01

Abstract The microdosimetric kinetic model (MKM) is widely used for estimating relative biological effectiveness (RBE)-weighted doses for various radiotherapies because it can determine the surviving fraction of irradiated cells based on only the lineal energy distribution, and it is independent of the radiation type and ion species. However, the applicability of the method to proton therapy has not yet been investigated thoroughly. In this study, we validated the RBE-weighted dose calculated by the MKM in tandem with the Monte Carlo code PHITS for proton therapy by considering the complete simulation geometry of the clinical proton beam line. The physical dose, lineal energy distribution, and RBE-weighted dose for a 155 MeV mono-energetic and spread-out Bragg peak (SOBP) beam of 60 mm width were evaluated. In estimating the physical dose, the calculated depth dose distribution by irradiating the mono-energetic beam using PHITS was consistent with the data measured by a diode detector. A maximum difference of 3.1% in the depth distribution was observed for the SOBP beam. In the RBE-weighted dose validation, the calculated lineal energy distributions generally agreed well with the published measurement data. The calculated and measured RBE-weighted doses were in excellent agreement, except at the Bragg peak region of the mono-energetic beam, where the calculation overestimated the measured data by ~15%. This research has provided a computational microdosimetric approach based on a combination of PHITS and MKM for typical clinical proton beams. The developed RBE-estimator function has potential application in the treatment planning system for various radiotherapies. PMID:29087492

An Empirical Test of Crisis, Social Selection, and Role Explanations of the Relationship between Marital Disruption and Psychological Distress: A Pooled Time-Series Analysis of Four-Wave Panel Data.

ERIC Educational Resources Information Center

Johnson, David R.; Wu, Jian

2002-01-01

Reviews three theoretical explanations (social role theory, crisis theory, social selection theory) for the reasons for psychological distress of divorced individuals. Evaluates the efficacy of these theories in a pooled analysis of married persons followed over 12 years. Results provide evidence that higher stress levels of the divorced primarily…

Early-life stress and reproductive cost: A two-hit developmental model of accelerated aging?

PubMed

Shalev, Idan; Belsky, Jay

2016-05-01

Two seemingly independent bodies of research suggest a two-hit model of accelerated aging, one highlighting early-life stress and the other reproduction. The first, informed by developmental models of early-life stress, highlights reduced longevity effects of early adversity on telomere erosion, whereas the second, informed by evolutionary theories of aging, highlights such effects with regard to reproductive cost (in females). The fact that both early-life adversity and reproductive effort are associated with shorter telomeres and increased oxidative stress raises the prospect, consistent with life-history theory, that these two theoretical frameworks currently informing much research are tapping into the same evolutionary-developmental process of increased senescence and reduced longevity. Here we propose a mechanistic view of a two-hit model of accelerated aging in human females through (a) early-life adversity and (b) early reproduction, via a process of telomere erosion, while highlighting mediating biological embedding mechanisms that might link these two developmental aging processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Measurement of microdosimetric spectra with a wall-less tissue-equivalent proportional counter for a 290 MeV/u 12C beam.

PubMed

Tsuda, Shuichi; Sato, Tatsuhiko; Takahashi, Fumiaki; Satoh, Daiki; Endo, Akira; Sasaki, Shinichi; Namito, Yoshihito; Iwase, Hiroshi; Ban, Shuichi; Takada, Masashi

2010-09-07

The frequency distribution of the lineal energy, y, of a 290 MeV/u carbon beam was measured to obtain the dose-weighted mean of y and compare it with the linear energy transfer (LET). In the experiment, a wall-less tissue-equivalent proportional counter (TEPC) in a cylindrical volume with a simulated diameter of 0.72 microm was used. The measured frequency distribution of y as well as its dose-mean value agrees within 10% uncertainty with the corresponding data from microdosimetric calculations using the PHITS code. The ratio of the measured dose-mean lineal energy to the LET of the 290 MeV/u carbon beam is 0.73, which is much smaller than the corresponding data obtained by a wall TEPC. This result demonstrates that a wall-less TEPC is necessary to precisely measure the dose-mean of y for energetic heavy ion beams.

Fluence-based and microdosimetric event-based methods for radiation protection in space

NASA Technical Reports Server (NTRS)

Curtis, Stanley B.; Meinhold, C. B. (Principal Investigator)

2002-01-01

The National Council on Radiation Protection and Measurements (NCRP) has recently published a report (Report #137) that discusses various aspects of the concepts used in radiation protection and the difficulties in measuring the radiation environment in spacecraft for the estimation of radiation risk to space travelers. Two novel dosimetric methodologies, fluence-based and microdosimetric event-based methods, are discussed and evaluated, along with the more conventional quality factor/LET method. It was concluded that for the present, any reason to switch to a new methodology is not compelling. It is suggested that because of certain drawbacks in the presently-used conventional method, these alternative methodologies should be kept in mind. As new data become available and dosimetric techniques become more refined, the question should be revisited and that in the future, significant improvement might be realized. In addition, such concepts as equivalent dose and organ dose equivalent are discussed and various problems regarding the measurement/estimation of these quantities are presented.

Derivation of dynamo current drive in a closed-current volume and stable current sustainment in the HIT-SI experiment

NASA Astrophysics Data System (ADS)

Hossack, A. C.; Sutherland, D. A.; Jarboe, T. R.

2017-02-01

A derivation is given showing that the current inside a closed-current volume can be sustained against resistive dissipation by appropriately phased magnetic perturbations. Imposed-dynamo current drive theory is used to predict the toroidal current evolution in the helicity injected torus with steady inductive helicity injection (HIT-SI) experiment as a function of magnetic fluctuations at the edge. Analysis of magnetic fields from a HIT-SI discharge shows that the injector-imposed fluctuations are sufficient to sustain the measured toroidal current without instabilities whereas the small, plasma-generated magnetic fluctuations are not sufficiently large to sustain the current.

On the use of LiF:Mg,Ti thermoluminescence dosemeters in space--a critical review.

PubMed

Horowitz, Y S; Satinger, D; Fuks, E; Oster, L; Podpalov, L

2003-01-01

The use of LiF:Mg,Ti thermoluminescence dosemeters (TLDs) in space radiation fields is reviewed. It is demonstrated in the context of modified track structure theory and microdosimetric track structure theory that there is no unique correlation between the relative thermoluminescence (TL) efficiency of heavy charged particles, neutrons of all energies and linear energy transfer (LET). Many experimental measurements dating back more than two decades also demonstrate the multivalued, non-universal, relationship between relative TL efficiency and LET. It is further demonstrated that the relative intensities of the dosimetric peaks and especially the high-temperature structure are dependent on a large number of variables, some controllable, some not. It is concluded that TL techniques employing the concept of LET (e.g. measurement of total dose, the high-temperature ratio (HTR) methods and other combinations of the relative TL efficiency of the various peaks used to estimate average Q or simulate Q-LET relationships) should be regarded as lacking a sound theoretical basis, highly prone to error and, as well, lack of reproducibility/universality due to the absence of a standardised experimental protocol essential to reliable experimental methodology.

The use and role of open source software applications in public and not-for-profit hospitals in the United States.

PubMed

Vest, Joshua R; Stephens, James H

2013-01-01

The potential cost savings and customizability of open source software (OSS) may be particularly attractive for hospitals. However, numerous health-care-specific OSS applications exist, the adoption of OSS health information technology (HIT) applications is not widespread in the United States. This disconnect between the availability of promising software and low adoption raises the basic question: If OSS HIT is so advantageous, why are more health care organizations not using it? We interviewed the chief information officer, or equivalent position, at 17 not-for-profit and public hospitals across the United States. Through targeted recruitment, our sample included nine hospitals using OSS HIT and eight hospitals not using OSS HIT. The open-ended interview questions were guided by domains included in the fit-viability theory, an organizational-level innovation adoption framework, and those suggested by a review of the literature. Transcripts were analyzed using an inductive and comparative approach, which involved an open coding for relevant themes. Interviews described the state of OSS use in hospitals. Specifically, general OSS applications were widely used by IT professionals. In addition, hospitals using OSS HIT still relied heavily on vendor support. In terms of why decisions arose to use OSS HIT, several hospitals using OSS HIT noted the cost advantages. In contrast, hospitals avoiding OSS HIT were clear, OSS as a class did not fit with clinical work and posed too much risk. Perceptions of OSS HIT ranged from enthusiastic embracement to resigned adoption, to refusal, to abandonment. Some organizations were achieving success with their OSS HIT choices, but they still relied on vendors for significant support. The decision to adopt OSS HIT was not uniform but contingent upon views of the risk posed by the technology, economic factors, and the hospital's existing capabilities.

Technological iatrogenesis: the manifestation of inadequate organizational planning and the integration of health information technology.

PubMed

Palmieri, Patrick Albert; Peterson, Lori T; Corazzo, Luciano Bedoya

2011-01-01

The Institute of Medicine (IOM) views Health Information Technology (HIT) as an essential organizational prerequisite for the delivery of safe, reliable, and cost-effective health services. However, HIT presents the proverbial double-edged sword in generating solutions to improve system performance while facilitating the genesis of novel iatrogenic problems. Incongruent organizational processes give rise to technological iatrogenesis or the unintended consequences to system integrity and the resulting organizational outcomes potentiated by incongruent organizational-technological interfaces. HIT is a disruptive innovation for health services organizations but remains an overlooked organizational development (OD) concern. Recognizing the technology-organizational misalignments that result from HIT adoption is important for leaders seeking to eliminate sources of system instability. The Health Information Technology Iatrogenesis Model (HITIM) provides leaders with a conceptual framework from which to consider HIT as an instrument for organizational development. Complexity and Diffusion of Innovation theories support the framework that suggests each HIT adoption functions as a technological change agent. As such, leaders need to provide operational oversight to managers undertaking system change via HIT implementation. Traditional risk management tools, such as Failure Mode Effect Analysis and Root Cause Analysis, provide proactive pre- and post-implementation appraisals to verify system stability and to enhance system reliability. Reconsidering the use of these tools within the context of a new framework offers leaders guidance when adopting HIT to achieve performance improvement and better outcomes.

The current status of REH theory. [Random Evolutionary Hits in biological molecular evolution

NASA Technical Reports Server (NTRS)

Holmquist, R.; Jukes, T. H.

1981-01-01

A response is made to the evaluation of Fitch (1980) of REH (random evolutionary hits) theory for the evolutionary divergence of proteins and nucleic acids. Correct calculations for the beta hemoglobin mRNAs of the human, mouse and rabbit in the absence and presence of selective constraints are summarized, and it is shown that the alternative evolutionary analysis of Fitch underestimates the total fixed mutations. It is further shown that the model used by Fitch to test for the completeness of the count of total base substitutions is in fact a variant of REH theory. Considerations of the variance inherent in evolutionary estimations are also presented which show the REH model to produce no more variance than other evolutionary models. In the reply, it is argued that, despite the objections raised, REH theory applied to proteins gives inaccurate estimates of total gene substitutions. It is further contended that REH theory developed for nucleic sequences suffers from problems relating to the frequency of nucleotide substitutions, the identity of the codons accepting silent and amino acid-changing substitutions, and estimate uncertainties.

Hot pixel generation in active pixel sensors: dosimetric and micro-dosimetric response

NASA Technical Reports Server (NTRS)

Scheick, Leif; Novak, Frank

2003-01-01

The dosimetric response of an active pixel sensor is analyzed. heavy ions are seen to damage the pixel in much the same way as gamma radiation. The probability of a hot pixel is seen to exhibit behavior that is not typical with other microdose effects.

Thematic Progression Analysis in Teaching Explanation Writing

ERIC Educational Resources Information Center

Yang, Xueqian

2008-01-01

Thematic Progression theory explains textual meanings of how experiential and interpersonal meanings are organized in a linear and coherent way. Employing the rationale of T-P theory, this article analyses a lesson plan of teaching Explanation, and shows that T-P analysis can be employed in teaching writing.

Contrastive Constraints Guide Explanation-Based Category Learning

ERIC Educational Resources Information Center

Chin-Parker, Seth; Cantelon, Julie

2017-01-01

This paper provides evidence for a contrastive account of explanation that is motivated by pragmatic theories that recognize the contribution that context makes to the interpretation of a prompt for explanation. This study replicates the primary findings of previous work in explanation-based category learning (Williams & Lombrozo, 2010),…

Explanation and the Nature of Scientific Knowledge

ERIC Educational Resources Information Center

McCain, Kevin

2015-01-01

Explaining phenomena is a primary goal of science. Consequently, it is unsurprising that gaining a proper understanding of the nature of explanation is an important goal of science education. In order to properly understand explanation, however, it is not enough to simply consider theories of the nature of explanation. Properly understanding…

Reasoning in explanation-based decision making.

PubMed

Pennington, N; Hastie, R

1993-01-01

A general theory of explanation-based decision making is outlined and the multiple roles of inference processes in the theory are indicated. A typology of formal and informal inference forms, originally proposed by Collins (1978a, 1978b), is introduced as an appropriate framework to represent inferences that occur in the overarching explanation-based process. Results from the analysis of verbal reports of decision processes are presented to demonstrate the centrality and systematic character of reasoning in a representative legal decision-making task.

A generalized target theory and its applications.

PubMed

Zhao, Lei; Mi, Dong; Hu, Bei; Sun, Yeqing

2015-09-28

Different radiobiological models have been proposed to estimate the cell-killing effects, which are very important in radiotherapy and radiation risk assessment. However, most applied models have their own scopes of application. In this work, by generalizing the relationship between "hit" and "survival" in traditional target theory with Yager negation operator in Fuzzy mathematics, we propose a generalized target model of radiation-induced cell inactivation that takes into account both cellular repair effects and indirect effects of radiation. The simulation results of the model and the rethinking of "the number of targets in a cell" and "the number of hits per target" suggest that it is only necessary to investigate the generalized single-hit single-target (GSHST) in the present theoretical frame. Analysis shows that the GSHST model can be reduced to the linear quadratic model and multitarget model in the low-dose and high-dose regions, respectively. The fitting results show that the GSHST model agrees well with the usual experimental observations. In addition, the present model can be used to effectively predict cellular repair capacity, radiosensitivity, target size, especially the biologically effective dose for the treatment planning in clinical applications.

The Covering Law Model in Communication Inquiry.

ERIC Educational Resources Information Center

Berger, Charles R.

The first section of this paper defines covering law explanation as a theory which maintains that explanation may be achieved, and may be achieved, by subsuming what is to be explained under a general law. The model is examined in light of the deductive-nomological explanation, the deductive-statistical explanation, and the inductive-statistical…

Does who you know in the positional hierarchy protect or hurt? Social capital, comparative reference group, and depression in two societies.

PubMed

Song, Lijun

2015-07-01

Does the socioeconomic status (SES) that one's (ego's) network members (alters) occupy indicate social resources or social comparison standards in the dynamics of health across culture? Using nationally representative data simultaneously collected from the United States and urban China, this study examines two competing theories-social capital and comparative reference group-in the two societies and compares their different application across the two societies using two cultural explanations, relational dependence and self-evaluation motive. Social capital theory expects absolute accessed SES and the size of higher accessed socioeconomic positions to protect health, and the size of lower accessed socioeconomic positions to harm health. But comparative reference group theory predicts the opposite. Additionally, the relational dependence explanation anticipates social capital theory to be more applicable to urban China and comparative reference group theory to be more applicable to the United States. The self-evaluation motive explanation expects the same pattern across the two societies in the examination of the size of lower accessed socioeconomic positions but the opposite pattern in the analysis of absolute accessed SES and the size of higher accessed socioeconomic positions. This study focuses on depressive symptoms and measures accessed occupational status. Results are consistent with the self-evaluation motive explanation. They support both social capital theory and comparative reference group theory in the United States but only the latter theory in urban China. Copyright © 2015 Elsevier Ltd. All rights reserved.

A quantum probability explanation for violations of ‘rational’ decision theory

PubMed Central

Pothos, Emmanuel M.; Busemeyer, Jerome R.

2009-01-01

Two experimental tasks in psychology, the two-stage gambling game and the Prisoner's Dilemma game, show that people violate the sure thing principle of decision theory. These paradoxical findings have resisted explanation by classical decision theory for over a decade. A quantum probability model, based on a Hilbert space representation and Schrödinger's equation, provides a simple and elegant explanation for this behaviour. The quantum model is compared with an equivalent Markov model and it is shown that the latter is unable to account for violations of the sure thing principle. Accordingly, it is argued that quantum probability provides a better framework for modelling human decision-making. PMID:19324743

Microdosimetric considerations of effects of heavy ions on E. coli K-12 mutants.

PubMed

Takahashi, T; Yatagai, F; Izumo, K

1992-01-01

The inactivation cross sections of E. coli K-12 recombination-deficient mutants, JC1553 (recA) and AB2470 (recB), for several MeV/u alpha-particles and N ions have been successfully analyzed by Katz's target theory in which radiosensitivity parameter E0 is assumed to be LET independent and equal to D37 for gamma-rays. For E. coli K-12 wild type, AB1157 (rec+, uvr+), however, it is impossible to interpret the inactivation cross section data by an LET-independent E0-value. In the latter case, as in the case of B. subtilis spore, it is necessary to assume that the radiosensitivity of the target for the core of a heavy ion is higher than that for delta-electrons. As well as Waligorski, Hamm and Katz's dose, the dose around the trajectory of an ion based on Tabata and Ito's energy deposition algorithm for electrons has been used in the course of analysis.

The Interdependencies of Theory Formation, Revision, and Experimentation

DTIC Science & Technology

1988-06-01

as a candidate explanation for why evaporation stopped. We conclude this section with a review of the two techniques. An integrated design and the...Experiment design . Typically, there will be a number of different ways to change a theory to explain a new phenomenon. Experiments are designed to...efforts, each approach is designed to perform theory development autonomously. V1AL conjectures explanations of the new behavior based on its similarity to

Reduction of plasma density in the Helicity Injected Torus with Steady Inductance experiment by using a helicon pre-ionization source.

PubMed

Hossack, Aaron C; Firman, Taylor; Jarboe, Thomas R; Prager, James R; Victor, Brian S; Wrobel, Jonathan S; Ziemba, Timothy

2013-10-01

A helicon based pre-ionization source has been developed and installed on the Helicity Injected Torus with Steady Inductance (HIT-SI) spheromak. The source initiates plasma breakdown by injecting impurity-free, unmagnetized plasma into the HIT-SI confinement volume. Typical helium spheromaks have electron density reduced from (2-3) × 10(19) m(-3) to 1 × 10(19) m(-3). Deuterium spheromak formation is possible with density as low as 2 × 10(18) m(-3). The source also enables HIT-SI to be operated with only one helicity injector at injector frequencies above 14.5 kHz. A theory explaining the physical mechanism driving the reduction of breakdown density is presented.

Organizations disseminating health messages: the roles of organizational identification and HITs.

PubMed

Stephens, Keri K; Goins, Elizabeth S; Dailey, Stephanie L

2014-01-01

Research into the dissemination of health information now includes more focus on how various organizations (e.g., beauty shops, schools, workplaces, and churches) and health information technologies (HITs) reach and affect audiences. One relational feature of organizations is identification--the feeling of belongingness. Our study explores how it influences audiences, especially in combination with HITs such as e-mail, websites, and social media. We use social identity theory to predict how organizational identification and social media might function in health communication. Using a 3 × 2 experimental design, we find that people's identification with a message source mediates the effect of social media on outcomes. These findings improve our understanding of when organizations might be most helpful for disseminating health information.

Toward a comprehensive theory for the sweeping of trapped radiation by inert orbiting matter

NASA Technical Reports Server (NTRS)

Fillius, Walker

1988-01-01

There is a need to calculate loss rates when trapped Van Allen radiation encounters inert orbiting material such as planetary rings and satellites. An analytic expression for the probability of a hit in a bounce encounter is available for all cases where the absorber is spherical and the particles are gyrotropically distributed on a cylindrical flux tube. The hit probability is a function of the particle's pitch angle, the size of the absorber, and the distance between the flux tube and the absorber when distances are scaled to the gyroradius of a particle moving perpendicular to the magnetic field. Using this expression, hit probabilities in drift encounters were computed for all regimes of particle energies and absorber sizes.

Beable-guided quantum theories: Generalizing quantum probability laws

NASA Astrophysics Data System (ADS)

Kent, Adrian

2013-02-01

Beable-guided quantum theories (BGQT) are generalizations of quantum theory, inspired by Bell's concept of beables. They modify the quantum probabilities for some specified set of fundamental events, histories, or other elements of quasiclassical reality by probability laws that depend on the realized configuration of beables. For example, they may define an additional probability weight factor for a beable configuration, independent of the quantum dynamics. Beable-guided quantum theories can be fitted to observational data to provide foils against which to compare explanations based on standard quantum theory. For example, a BGQT could, in principle, characterize the effects attributed to dark energy or dark matter, or any other deviation from the predictions of standard quantum dynamics, without introducing extra fields or a cosmological constant. The complexity of the beable-guided theory would then parametrize how far we are from a standard quantum explanation. Less conservatively, we give reasons for taking suitably simple beable-guided quantum theories as serious phenomenological theories in their own right. Among these are the possibility that cosmological models defined by BGQT might in fact fit the empirical data better than any standard quantum explanation, and the fact that BGQT suggest potentially interesting nonstandard ways of coupling quantum matter to gravity.

An ancient explanation of presbyopia based on binocular vision.

PubMed

Barbero, Sergio

2014-06-01

Presbyopia, understood as the age-related loss of ability to clearly see near objects, was known to ancient Greeks. However, few references to it can be found in ancient manuscripts. A relevant discussion on presbyopia appears in a book called Symposiacs written by Lucius Mestrius Plutarchus around 100 A.C. In this work, Plutarch provided four explanations of presbyopia, associated with different theories of vision. One of the explanations is particularly interesting as it is based on a binocular theory of vision. In this theory, vision is produced when visual rays, emanating from the eyes, form visual cones that impinge on the objects to be seen. Visual rays coming from old people's eyes, it was supposed, are weaker than those from younger people's eyes; so the theory, to be logically coherent, implies that this effect is compensated by the increase in light intensity due to the overlapping, at a certain distance, of the visual cones coming from both eyes. Thus, it benefits the reader to move the reading text further away from the eyes in order to increase the fusion area of both visual cones. The historical hypothesis taking into consideration that the astronomer Hipparchus of Nicaea was the source of Plutarch's explanation of the theory is discussed. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Theoretical Evaluation of the Radiation Hazards from Cosmic Rays Within Space Vehicles

NASA Technical Reports Server (NTRS)

Katz, Robert

1998-01-01

We may summarize our efforts as follows: a. Improvement of our calculations of the radial dose distribution from delta rays ejected in the passage of heavy ions through matter through the application of new data to a previous calculation by Kobetich and Katz (1968). Supplementing this calculation, we have found the radial distribution of electron energy spectra and the radial distribution of microdosimetric quantities (Cucinotta et al, 1996, 1997). b. Extension of the Katz model of cellular survival to bacteria, to lethal mutations in C. Elegans in vivo, to mutation induction in vitro, to thindown in radiobiology (observed experimentally at GSI, Darmstadt, and there called "Darmstadt hooks", predicted by Katz theory years before GSI was constructed). c. Coupling the Katz theory of RBE to the NASA theory of the diffusion of heavy ion beams in matter to yield predictions of the effects for monoenergetic heavy ion beams as well as range modulated beams used for cancer therapy. Here we have directed attention to the role of "ion-kill" (the effects produced by heavy ions passing through the nucleus of a cell), responsible for increased RBE, decreased OER, and reduced repair. We predict that the use of beams of heavy ions in cancer therapy will create late effect problems for fractionated therapy. We highlight also the damage by "ion-kill", from single heavy ions in the cosmic rays, to the central nervous system in space flight. d. The coupling of Katz theory and the NASA theory of heavy ion diffusion and penetration through matter, and knowledge of the space radiation environment, has been applied to design of shielding, to the cell damage in space flight.

Microdosimetric Measurements on Nuclear Reactions.

DTIC Science & Technology

1983-01-01

applied to the field of radiation induced mutations. 130 BIBL OGI1APHY 1. T.C. May and M.H. Woods, IEEE Transactions on Electron Devices ED-l26, 2...McNulty, IEEE Transactions on Nuclear Science 11Sz29, 2012 (1982). 42. F.B. McLean and T.R. Oldham, ibid., NS-2.2, 2018 (1982). 43. G.C. Messenger

Children's memories of removal: a test of attachment theory.

PubMed

Melinder, Annika; Baugerud, Gunn Astrid; Ovenstad, Kristianne Stigsdatter; Goodman, Gail S

2013-02-01

We report a study of parents' attachment orientations and children's autobiographical memory for an experience that according to Bowlby's (1982) attachment theory should be particularly threatening-children's forced separation from their parents. It was hypothesized that individual differences in parents' attachment orientations would be associated with children's distress and memory for this highly traumatic event. Children (n = 28) were observed during forced removal from home or school by Child Protective Services due to allegations of child maltreatment. Children's memory for the removal was tested 1 week later, and biological parents (n = 28) completed an adult attachment measure. Parental attachment anxiety significantly predicted children's distress during less stressful phases of the removal, R(2) = .25, and parents' attachment-related avoidance predicted fewer correct memory reports from the children (i.e., fewer hits to open-ended questions, R(2) = .16, and fewer hits to direct questions, R(2) = .27). The findings indicate that attachment theory provides important guidance for understanding children's autobiographical memory for traumatic events. Copyright © 2013 International Society for Traumatic Stress Studies.

Public engagement as a means of restoring public trust in science--hitting the notes, but missing the music?

PubMed

Wynne, Brian

2006-01-01

This paper analyses the recent widespread moves to 'restore' public trust in science by developing an avowedly two-way, public dialogue with science initiatives. Noting how previously discredited and supposedly abandoned public deficit explanations of 'mistrust' have actually been continually reinvented, it argues that this is a symptom of a continuing failure of scientific and policy institutions to place their own science-policy institutional culture into the frame of dialogue, as possible contributory cause of the public mistrust problem. Copyright 2006 S. Karger AG, Basel.

An Investigation of Factors Affecting the Degree of Naïve Impetus Theory Application

NASA Astrophysics Data System (ADS)

Liu, Xiufeng; MacIsaac, Dan

2005-03-01

This study investigates factors affecting the degree of novice physics students' application of the naïve impetus theory. Six hundred and fourteen first-year university engineering physics students answered the Force Concept Inventory as a pre-test for their calculus-based course. We examined the degree to which students consistently applied the naïve impetus theory across different items. We used a 2-way repeated measures ANOVA and linear regression to analyze data coded from incorrect student responses. It was found that there were statistically significant main effects for item familiarity and item requirement for explanation vs. prediction on the measured degree of impetus theory application. Student course grades had no significant effect on impetus theory application. When faced with items that were unfamiliar and predictive, students appeared to rely on non-theoretical, knowledge-in-pieces reasoning. Reasoning characteristic of naïve theories was more frequently applied when students were completing familiar problem tasks that required explanation. When considering all the above factors simultaneously, we found that the degree of naïve impetus theory application by students is attributable to variables in the following order: familiarity, prediction, and explanation.

When Wife-Beating Is Not Necessarily Abuse: A Feminist and Cross-Cultural Analysis of the Concept of Abuse as Expressed by Tibetan Survivors of Domestic Violence.

PubMed

Rajan, Hamsa

2016-11-20

This article describes the views of Tibetan women who have experienced physical violence from male intimate partners. How they conceptualise abuse, their views on acceptable versus unacceptable hitting, and the acts besides hitting which they felt to be unacceptable or abusive, are explored. Views of survivors' relatives/friends and men who have hit their wives are also included. Western-based domestic violence theory is shown to be incommensurate with abuse in particular socio-cultural settings. As feminist scholars emphasize listening deeply to voices of women in the global South, this article demonstrates how such listening might be undertaken when the views expressed by women diverge from feminism. © The Author(s) 2016.

A Theoretical Model of Health Information Technology Usage Behaviour with Implications for Patient Safety

ERIC Educational Resources Information Center

Holden, Richard J.; Karsh, Ben-Tzion

2009-01-01

Primary objective: much research and practice related to the design and implementation of information technology in health care has been atheoretical. It is argued that using extant theory to develop testable models of health information technology (HIT) benefits both research and practice. Methods and procedures: several theories of motivation,…

Between cheap and costly signals: the evolution of partially honest communication.

PubMed

Zollman, Kevin J S; Bergstrom, Carl T; Huttegger, Simon M

2013-01-07

Costly signalling theory has become a common explanation for honest communication when interests conflict. In this paper, we provide an alternative explanation for partially honest communication that does not require significant signal costs. We show that this alternative is at least as plausible as traditional costly signalling, and we suggest a number of experiments that might be used to distinguish the two theories.

The Many Roles of "Explanation" in Science Education: A Case Study

ERIC Educational Resources Information Center

Rocksén, Miranda

2016-01-01

In this paper the role of explanations is discussed in relation to possible consequences originating in the polysemy of the word explanation. The present study is a response to conceptual confusions that have arisen in the intersection between theory and practice, and between science education literature and communication in authentic science…

Attributional Bias Instrument (ABI): Validation of a Measure to Assess Ability and Effort Explanations for Math Performance

ERIC Educational Resources Information Center

Espinoza, Penelope P.; Quezada, Stephanie A.; Rincones, Rodolfo; Strobach, E. Natalia; Gutierrez, Maria Armida Estrada

2012-01-01

The present work investigates the validation of a newly developed instrument, the attributional bias instrument, based on achievement attribution theories that distinguish between effort and ability explanations of behavior. The instrument further incorporates the distinction between explanations for success versus failure in academic performance.…

Microdosimetric Modeling of Biological Effectiveness for Boron Neutron Capture Therapy Considering Intra- and Intercellular Heterogeneity in 10B Distribution.

PubMed

Sato, Tatsuhiko; Masunaga, Shin-Ichiro; Kumada, Hiroaki; Hamada, Nobuyuki

2018-01-17

We here propose a new model for estimating the biological effectiveness for boron neutron capture therapy (BNCT) considering intra- and intercellular heterogeneity in 10 B distribution. The new model was developed from our previously established stochastic microdosimetric kinetic model that determines the surviving fraction of cells irradiated with any radiations. In the model, the probability density of the absorbed doses in microscopic scales is the fundamental physical index for characterizing the radiation fields. A new computational method was established to determine the probability density for application to BNCT using the Particle and Heavy Ion Transport code System PHITS. The parameters used in the model were determined from the measured surviving fraction of tumor cells administrated with two kinds of 10 B compounds. The model quantitatively highlighted the indispensable need to consider the synergetic effect and the dose dependence of the biological effectiveness in the estimate of the therapeutic effect of BNCT. The model can predict the biological effectiveness of newly developed 10 B compounds based on their intra- and intercellular distributions, and thus, it can play important roles not only in treatment planning but also in drug discovery research for future BNCT.

Microdosimetric intercomparison of BNCT beams at BNL and MIT.

PubMed

Burmeister, Jay; Riley, Kent; Coderre, Jeffrey A; Harling, Otto K; Ma, Ruimei; Wielopolski, Lucian; Kota, Chandrasekhar; Maughan, Richard L

2003-08-01

Microdosimetric measurements have been performed at the clinical beam intensities in two epithermal neutron beams, the Brookhaven Medical Research Reactor and the M67 beam at the Massachusetts Institute of Technology Research Reactor, which have been used to treat patients with Boron Neutron Capture Therapy (BNCT). These measurements offer an independent assessment of the dosimetry used at these two facilities, as well as provide information about the radiation quality not obtainable from conventional macrodosimetric techniques. Moreover, they provide a direct measurement of the absorbed dose resulting from the BNC reaction. BNC absorbed doses measured within this study are approximately 15% lower than those estimated using foil activation at both MIT and BNL. Finally, an intercomparison of the characteristics and radiation quality of these two clinical beams is presented. The techniques described here allow an accurate quantitative comparison of the physical absorbed dose as well as a measure of the biological effectiveness of the absorbed dose delivered by different epithermal beams. No statistically significant differences were observed in the predicted RBEs of these two beams. The methodology presented here can help to facilitate the effective sharing of clinical results in an effort to demonstrate the clinical utility of BNCT.

D'Arcy Thompson and the theory of transformations.

PubMed

Arthur, Wallace

2006-05-01

D'Arcy Thompson was a biologist, a mathematician and a classicist. His writing was great literature as well as great science. He is primarily known for a single book--On Growth and Form--and indeed for a single chapter within it, on his 'theory of transformations', which shows how the differences between the forms of related species can be represented geometrically. This theory cries out for causal explanation, which is something the great man eschewed. Perhaps the time is close when comparative developmental genetics will be able to provide such an explanation.

Biological Evolution and the History of the Earth Are Foundations of Science

NASA Astrophysics Data System (ADS)

2008-01-01

AGU affirms the central importance of including scientific theories of Earth history and biological evolution in science education. Within the scientific community, the theory of biological evolution is not controversial, nor have ``alternative explanations'' been found. This is why no competing theories are required by the U.S. National Science Education Standards. Explanations of natural phenomena that appeal to the supernatural or are based on religious doctrine-and therefore cannot be tested through scientific inquiry-are not scientific, and have no place in the science classroom.

Reduction of plasma density in the Helicity Injected Torus with Steady Inductance experiment by using a helicon pre-ionization source

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

Hossack, Aaron C.; Jarboe, Thomas R.; Victor, Brian S.

2013-10-15

A helicon based pre-ionization source has been developed and installed on the Helicity Injected Torus with Steady Inductance (HIT-SI) spheromak. The source initiates plasma breakdown by injecting impurity-free, unmagnetized plasma into the HIT-SI confinement volume. Typical helium spheromaks have electron density reduced from (2–3) × 10{sup 19} m{sup −3} to 1 × 10{sup 19} m{sup −3}. Deuterium spheromak formation is possible with density as low as 2 × 10{sup 18} m{sup −3}. The source also enables HIT-SI to be operated with only one helicity injector at injector frequencies above 14.5 kHz. A theory explaining the physical mechanism driving the reductionmore » of breakdown density is presented.« less

Using Self-Explanations in the Laboratory to Connect Theory and Practice: The Decision/ Explanation/Observation/Inference Writing Method

ERIC Educational Resources Information Center

Van Duzor, Andrea Gay

2016-01-01

While many faculty seek to use student-centered, inquiry-based approaches in teaching laboratories, transitioning from traditional to inquiry instruction can be logistically challenging. This paper outlines use of a laboratory notebook and report writing-to-learn method that emphasizes student self-explanations of procedures and outcomes,…

Microdosimetric investigation at the therapeutic proton beam facility of CATANA.

PubMed

De Nardo, L; Moro, D; Colautti, P; Conte, V; Tornielli, G; Cuttone, G

2004-01-01

Proton beams (62 Mev) are used by the Laboratori Nazionali del Sud of the Italian Institute of Nuclear Physics to treat eye melanoma tumours at the therapeutic facility called CATANA. A cylindrical slim tissue-equivalent proportional counter (TEPC) of 2.7 mm external diameter has been used to compare the radiation quality of two spread-out Bragg peaks (SOBP) at the CATANA proton beam.

Coupling Monte Carlo simulations with thermal analysis for correcting microdosimetric spectra from a novel micro-calorimeter

NASA Astrophysics Data System (ADS)

Fathi, K.; Galer, S.; Kirkby, K. J.; Palmans, H.; Nisbet, A.

2017-11-01

The high uncertainty in the Relative Biological Effectiveness (RBE) values of particle therapy beam, which are used in combination with the quantity absorbed dose in radiotherapy, together with the increase in the number of particle therapy centres worldwide necessitate a better understating of the biological effect of such modalities. The present novel study is part of performance testing and development of a micro-calorimeter based on Superconducting QUantum Interference Devices (SQUIDs). Unlike other microdosimetric detectors that are used for investigating the energy distribution, this detector provides a direct measurement of energy deposition at the micrometre scale, that can be used to improve our understanding of biological effects in particle therapy application, radiation protection and environmental dosimetry. Temperature rises of less than 1μK are detectable and when combined with the low specific heat capacity of the absorber at cryogenic temperature, extremely high energy deposition sensitivity of approximately 0.4 eV can be achieved. The detector consists of 3 layers: tissue equivalent (TE) absorber, superconducting (SC) absorber and silicon substrate. Ideally all energy would be absorbed in the TE absorber and heat rise in the superconducting layer would arise due to heat conduction from the TE layer. However, in practice direct particle absorption occurs in all 3 layers and must be corrected for. To investigate the thermal behaviour within the detector, and quantify any possible correction, particle tracks were simulated employing Geant4 (v9.6) Monte Carlo simulations. The track information was then passed to the COMSOL Multiphysics (Finite Element Method) software. The 3D heat transfer within each layer was then evaluated in a time-dependent model. For a statistically reliable outcome, the simulations had to be repeated for a large number of particles. An automated system has been developed that couples Geant4 Monte Carlo output to COMSOL for determining the expected distribution of proton tracks and their thermal contribution within the detector. The correction factor for a 3.8 MeV proton pencil beam was determined and applied to the expected spectra. The corrected microdosimetric spectra was shown to have a good agreement with the ideal spectra.

The training and support needs of faculty and students using a health information technology system were significant: a case study in a dental school.

PubMed

Hill, Heather K; Stewart, Denice C L; Ash, Joan S

2010-11-13

Health Information Technology Systems (HITS) are becoming more widely integrated into patient care in the dental school setting. The purpose of this study was to evaluate the impact of a chairside HITS on users in the dental school setting. Qualitative techniques, including interviews, focus groups and observations, were used. Using grounded theory, we saw 9 themes emerge. One theme of particular interest was that "training and support needs of end-users were significant." This paper explores this theme in detail and discusses the implications.

The Impact of the Geometrical Structure of the DNA on Parameters of the Track-Event Theory for Radiation Induced Cell Kill.

PubMed

Schneider, Uwe; Vasi, Fabiano; Besserer, Jürgen

2016-01-01

When fractionation schemes for hypofractionation and stereotactic body radiotherapy are considered, a reliable cell survival model at high dose is needed for calculating doses of similar biological effectiveness. An alternative to the LQ-model is the track-event theory which is based on the probabilities for one- and two two-track events. A one-track-event (OTE) is always represented by at least two simultaneous double strand breaks. A two-track-event (TTE) results in one double strand break. Therefore at least two two-track-events on the same or different chromosomes are necessary to produce an event which leads to cell sterilization. It is obvious that the probabilities of OTEs and TTEs must somehow depend on the geometrical structure of the chromatin. In terms of the track-event theory the ratio ε of the probabilities of OTEs and TTEs includes the geometrical dependence and is obtained in this work by simple Monte Carlo simulations. For this work it was assumed that the anchors of loop forming chromatin are most sensitive to radiation induced cell deaths. Therefore two adjacent tetranucleosomes representing the loop anchors were digitized. The probability ratio ε of OTEs and TTEs was factorized into a radiation quality dependent part and a geometrical part: ε = εion ∙ εgeo. εgeo was obtained for two situations, by applying Monte Carlo simulation for DNA on the tetranucleosomes itself and for linker DNA. Low energy electrons were represented by randomly distributed ionizations and high energy electrons by ionizations which were simulated on rays. εion was determined for electrons by using results from nanodosimetric measurements. The calculated ε was compared to the ε obtained from fits of the track event model to 42 sets of experimental human cell survival data. When the two tetranucleosomes are in direct contact and the hits are randomly distributed εgeo and ε are 0.12 and 0.85, respectively. When the hits are simulated on rays εgeo and ε are 0.10 and 0.71. For the linker-DNA εgeo and ε for randomly distributed hits are 0.010 and 0.073, and for hits on rays 0.0058 and 0.041, respectively. The calculated ε fits the experimentally obtained ε = 0.64±0.32 best for hits on the tetranucleosome when they are close to each other both, for high and low energy electrons. The parameter εgeo of the track event model was obtained by pure geometrical considerations of the chromatin structure and is 0.095 ± 0.022. It can be used as a fixed parameter in the track-event theory.

More than culture: structural racism, intersectionality theory, and immigrant health.

PubMed

Viruell-Fuentes, Edna A; Miranda, Patricia Y; Abdulrahim, Sawsan

2012-12-01

Explanations for immigrant health outcomes often invoke culture through the use of the concept of acculturation. The over reliance on cultural explanations for immigrant health outcomes has been the topic of growing debate, with the critics' main concern being that such explanations obscure the impact of structural factors on immigrant health disparities. In this paper, we highlight the shortcomings of cultural explanations as currently employed in the health literature, and argue for a shift from individual culture-based frameworks, to perspectives that address how multiple dimensions of inequality intersect to impact health outcomes. Based on our review of the literature, we suggest specific lines of inquiry regarding immigrants' experiences with day-to-day discrimination, as well as on the roles that place and immigration policies play in shaping immigrant health outcomes. The paper concludes with suggestions for integrating intersectionality theory in future research on immigrant health. Copyright © 2012 Elsevier Ltd. All rights reserved.

The moon illusion: II. A reference theory.

PubMed

Baird, J C

1982-09-01

The present theory provides explanations for the moon illusion and related issues involving size and distance perception in natural, outdoor settings. Although some assumptions of previous theories are rejected, other pivotal aspects are retained in this formulation. In particular, the present theory states that both the sky and ground are important referents in judging the spatial extent of the moon. Neither factor alone can account for all the available data, but quantitative models incorporating both factors do quite well when applied to the parametric findings of Holway and Boring, as well as to the results obtained by Kaufman and Rock. The reference theory and its associated class of specific models suggest new theoretical directions and experimental tests to narrow yet further the selection of appropriate explanations for one of visual perception's oldest unsolved puzzles.

Toward a comprehensive theory for the sweeping of trapped radiation by inert orbiting matter

NASA Technical Reports Server (NTRS)

Fillius, Walker

1988-01-01

There is a need to calculate loss rates when trapped Van Allen radiation encounters inert orbiting material such as planetary rings and satellites. An analytic expression for the probability of a hit in a bounce encounter is available for all cases where the absorber is spherical and the particles are gyrotropically distributed on a cylindrical flux tube. The hit probability is a function of the particle's pitch angle, the size of the absorber, and the distance between flux tube and absorber, when distances are scaled to the gyroradius of a particle moving perpendicular to the magnetic field. Using this expression, hit probabilities have been computed in drift encounters for all regimes of particle energies and absorber sizes. This technique generalizes the approach to sweeping lifetimes, and is particularly suitable for attacking the inverse problem, where one is given a sweeping signature and wants to deduce the properties of the absorber(s).

Models, theory structure and mechanisms in biochemistry: The case of allosterism.

PubMed

Alleva, Karina; Díez, José; Federico, Lucia

2017-06-01

From the perspective of the new mechanistic philosophy, it has been argued that explanatory causal mechanisms in some special sciences such as biochemistry and neurobiology cannot be captured by any useful notion of theory, or at least by any standard notion. The goal of this paper is to show that a model-theoretic notion of theory, and in particular the structuralist notion of a theory-net already applied to other unified explanatory theories, adequately suits the MWC allosteric mechanism explanatory set-up. We also argue, contra some mechanistic claims questioning the use of laws in biological explanations, that the theory reconstructed in this way essentially contains non-accidental regularities that qualify as laws, and that taking into account these lawful components, it is possible to explicate the unified character of the theory. Finally, we argue that, contrary to what some mechanists also claim, functional explanations that do not fully specify the mechanistic structure are not defective or incomplete in any relevant sense, and that functional components are perfectly explanatory. The conclusion is that, as some authors have emphasized in other fields (Walmsley 2008), particular elements of traditional approaches do not contradict but rather complement the new mechanist philosophy, and taken together they may offer a more complete understanding of special sciences and the variety of explanations they provide. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multiple compliant processes: A reply to Haslam and Reicher on the engaged followership explanation of 'obedience' in Milgram's experiments.

PubMed

Hollander, Matthew M; Turowetz, Jason

2018-04-01

Haslam and Reicher (2018, Br. J. Soc. Psychol., 57, 292-300) offer a thoughtful rejoinder to our critique (Hollander & Turowetz, 2017, Br. J. Soc. Psychol, 56, 655-674) of their theory of engaged followership, currently the most important explanation of 'obedient' behaviour in the Milgram paradigm. Our immersion in Milgram's archived audio recordings has led us to new findings about participants' perspectives, as well as to dissatisfaction with the theory in its present version. Following a brief discussion of our findings, which cast the theory in doubt, we respond to Haslam and Reicher's argument that these data may in fact be consistent with it. Our response identifies three limitations of engaged followership emerging from this debate. Despite the strengths of the theory and these authors' impressive re-analysis of our findings, important reasons remain for scepticism that engaged followership operated in Milgram's experiments in the way, and to the extent, that they claim. Rather, 'obedience' appears amenable to multiple empirically grounded explanations, only one of which is engaged followership. © 2018 The British Psychological Society.

The differential effects of tangible rewards and praise on intrinsic motivation: A comparison of cognitive evaluation theory and operant theory.

PubMed

Carton, J S

1996-01-01

Substantial research indicates that tangible rewards, such as money, prizes, and tokens, decrease response rates by undermining intrinsic motivation. In contrast, praise appears to increase response rates by enhancing intrinsic motivation. Based on their interpretation of available evidence, many social-cognitive researchers warn not to use tangible rewards in applied settings and to use praise instead. Furthermore, they suggest that the differential effects of the two types of rewards on intrinsic motivation cannot be explained using principles of operant psychology. Cognitive evaluation theory provides one of the most recent and widely cited social-cognitive explanations for the different effects of the two types of rewards on intrinsic motivation (Deci & Ryan, 1985). However, a review of existing research found little support for the explanations based on this theory and revealed three potential confounding effects: (a) temporal contiguity, (b) the number of reward administrations, and (c) discriminative stimuli associated with reward availability. These three confounding factors provide explanations for the effects of tangible rewards and praise on intrinsic motivation that are consistent with principles of operant psychology.

The differential effects of tangible rewards and praise on intrinsic motivation: A comparison of cognitive evaluation theory and operant theory

PubMed Central

Carton, John S.

1996-01-01

Substantial research indicates that tangible rewards, such as money, prizes, and tokens, decrease response rates by undermining intrinsic motivation. In contrast, praise appears to increase response rates by enhancing intrinsic motivation. Based on their interpretation of available evidence, many social-cognitive researchers warn not to use tangible rewards in applied settings and to use praise instead. Furthermore, they suggest that the differential effects of the two types of rewards on intrinsic motivation cannot be explained using principles of operant psychology. Cognitive evaluation theory provides one of the most recent and widely cited social-cognitive explanations for the different effects of the two types of rewards on intrinsic motivation (Deci & Ryan, 1985). However, a review of existing research found little support for the explanations based on this theory and revealed three potential confounding effects: (a) temporal contiguity, (b) the number of reward administrations, and (c) discriminative stimuli associated with reward availability. These three confounding factors provide explanations for the effects of tangible rewards and praise on intrinsic motivation that are consistent with principles of operant psychology. PMID:22478261

Causal-explanatory pluralism: How intentions, functions, and mechanisms influence causal ascriptions.

PubMed

Lombrozo, Tania

2010-12-01

Both philosophers and psychologists have argued for the existence of distinct kinds of explanations, including teleological explanations that cite functions or goals, and mechanistic explanations that cite causal mechanisms. Theories of causation, in contrast, have generally been unitary, with dominant theories focusing either on counterfactual dependence or on physical connections. This paper argues that both approaches to causation are psychologically real, with different modes of explanation promoting judgments more or less consistent with each approach. Two sets of experiments isolate the contributions of counterfactual dependence and physical connections in causal ascriptions involving events with people, artifacts, or biological traits, and manipulate whether the events are construed teleologically or mechanistically. The findings suggest that when events are construed teleologically, causal ascriptions are sensitive to counterfactual dependence and relatively insensitive to the presence of physical connections, but when events are construed mechanistically, causal ascriptions are sensitive to both counterfactual dependence and physical connections. The conclusion introduces an account of causation, an "exportable dependence theory," that provides a way to understand the contributions of physical connections and teleology in terms of the functions of causal ascriptions. Copyright © 2010 Elsevier Inc. All rights reserved.

A Social Control Perspective on Scientific Misconduct.

ERIC Educational Resources Information Center

Hackett, Edward J.

1994-01-01

Some explanations for scientific misconduct are examined, including those based on theories of individual psychopathology, anomie, and alienation. An alternative explanation, drawing on the concept of social control, is presented, and implications for research and policy are examined. (MSE)

Norwalk virus: How infectious is it?

EPA Science Inventory

Noroviruses are major agents of viral gastroenteritis worldwide. The infectivity of Norwalk virus, the prototype norovirus, has been studied in susceptible human volunteers. A new variant of the hit theory model of microbial infection was developed to estimate the variation in No...

Understanding Student Motivation

ERIC Educational Resources Information Center

Seifert, Timothy

2004-01-01

Contemporary theories of academic motivation seek to explain students' behaviours in academic settings. While each theory seems to possess its own constructs and unique explanations, these theories are actually closely tied together. In this theoretical study of motivation, several theories of motivation were described and an underlying theme of…

Competition explains limited attention and perceptual resources: implications for perceptual load and dilution theories.

PubMed

Scalf, Paige E; Torralbo, Ana; Tapia, Evelina; Beck, Diane M

2013-01-01

Both perceptual load theory and dilution theory purport to explain when and why task-irrelevant information, or so-called distractors are processed. Central to both explanations is the notion of limited resources, although the theories differ in the precise way in which those limitations affect distractor processing. We have recently proposed a neurally plausible explanation of limited resources in which neural competition among stimuli hinders their representation in the brain. This view of limited capacity can also explain distractor processing, whereby the competitive interactions and bias imposed to resolve the competition determine the extent to which a distractor is processed. This idea is compatible with aspects of both perceptual load and dilution models of distractor processing, but also serves to highlight their differences. Here we review the evidence in favor of a biased competition view of limited resources and relate these ideas to both classic perceptual load theory and dilution theory.

Proximity functions for electrons up to 10 keV

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

Chmelevsky, D.; Kellerer, A.M.; Terrissol, M.

1980-11-01

Proximity functions for electrons up to 10 keV in water are computed from simulated particle tracks. Numerical results are given for the differential functions t(x) and the integral functions T(x). Basic characteristics of these functions and their connections to other microdosimetric quantities are considered. As an example of the applicability of the proximity functions, the quantity y/sub D/ for spheres is derived from t(x).

Social Norms: Do We Love Norms Too Much?

PubMed

Bell, David C; Cox, Mary L

2015-03-01

Social norms are often cited as the cause of many social phenomena, especially as an explanation for prosocial family and relationship behaviors. And yet maybe we love the idea of social norms too much, as suggested by our failure to subject them to rigorous test. Compared to the detail in social norms theoretical orientations, there is very little detail in tests of normative theories. To provide guidance to researchers who invoke social norms as explanations, we catalog normative orientations that have been proposed to account for consistent patterns of action. We call on researchers to conduct tests of normative theories and the processes such theories assert.

Social Norms: Do We Love Norms Too Much?

PubMed Central

Bell, David C.; Cox, Mary L.

2014-01-01

Social norms are often cited as the cause of many social phenomena, especially as an explanation for prosocial family and relationship behaviors. And yet maybe we love the idea of social norms too much, as suggested by our failure to subject them to rigorous test. Compared to the detail in social norms theoretical orientations, there is very little detail in tests of normative theories. To provide guidance to researchers who invoke social norms as explanations, we catalog normative orientations that have been proposed to account for consistent patterns of action. We call on researchers to conduct tests of normative theories and the processes such theories assert. PMID:25937833

Superconducting properties of copper oxide high-temperature superconductors

PubMed Central

Chen, Guanhua; Langlois, Jean-Marc; Guo, Yuejin; Goddard, William A.

1989-01-01

The equations for the magnon pairing theory of high-temperature copper-oxide-based superconductors are solved and used to calculate several properties, leading to results for specific heat and critical magnetic fields consistent with experimental results. In addition, the theory suggests an explanation of why there are two sets of transition temperatures (Tc ≈ 90 K and Tc ≈ 55 K) for the Y1Ba2Cu3O6+x class of superconductors. It also provides an explanation of why La2-xSrxCuO4 is a superconductor for only a small range of x (and suggests an experiment to independently test the theory). These results provide support for the magnon pairing theory of high-temperature superconductors. On the basis of the theory, some suggestions are made for improving these materials. PMID:16594038

Portfolios in Stochastic Local Search: Efficiently Computing Most Probable Explanations in Bayesian Networks

NASA Technical Reports Server (NTRS)

Mengshoel, Ole J.; Roth, Dan; Wilkins, David C.

2001-01-01

Portfolio methods support the combination of different algorithms and heuristics, including stochastic local search (SLS) heuristics, and have been identified as a promising approach to solve computationally hard problems. While successful in experiments, theoretical foundations and analytical results for portfolio-based SLS heuristics are less developed. This article aims to improve the understanding of the role of portfolios of heuristics in SLS. We emphasize the problem of computing most probable explanations (MPEs) in Bayesian networks (BNs). Algorithmically, we discuss a portfolio-based SLS algorithm for MPE computation, Stochastic Greedy Search (SGS). SGS supports the integration of different initialization operators (or initialization heuristics) and different search operators (greedy and noisy heuristics), thereby enabling new analytical and experimental results. Analytically, we introduce a novel Markov chain model tailored to portfolio-based SLS algorithms including SGS, thereby enabling us to analytically form expected hitting time results that explain empirical run time results. For a specific BN, we show the benefit of using a homogenous initialization portfolio. To further illustrate the portfolio approach, we consider novel additive search heuristics for handling determinism in the form of zero entries in conditional probability tables in BNs. Our additive approach adds rather than multiplies probabilities when computing the utility of an explanation. We motivate the additive measure by studying the dramatic impact of zero entries in conditional probability tables on the number of zero-probability explanations, which again complicates the search process. We consider the relationship between MAXSAT and MPE, and show that additive utility (or gain) is a generalization, to the probabilistic setting, of MAXSAT utility (or gain) used in the celebrated GSAT and WalkSAT algorithms and their descendants. Utilizing our Markov chain framework, we show that expected hitting time is a rational function - i.e. a ratio of two polynomials - of the probability of applying an additive search operator. Experimentally, we report on synthetically generated BNs as well as BNs from applications, and compare SGSs performance to that of Hugin, which performs BN inference by compilation to and propagation in clique trees. On synthetic networks, SGS speeds up computation by approximately two orders of magnitude compared to Hugin. In application networks, our approach is highly competitive in Bayesian networks with a high degree of determinism. In addition to showing that stochastic local search can be competitive with clique tree clustering, our empirical results provide an improved understanding of the circumstances under which portfolio-based SLS outperforms clique tree clustering and vice versa.

Overview of HIT-SI3 experiment: Simulations, Diagnostics, and Summary of Current Results

NASA Astrophysics Data System (ADS)

Penna, James; Jarboe, Thomas; Nelson, Brian; Hossack, Aaron; Sutherland, Derek; Morgan, Kyle; Hansen, Chris; Benedett, Thomas; Everson, Chris; Victor, Brian

2016-10-01

The Helicity Injected Torus - Steady Inductive 3(HIT-SI3)experiment forms and maintains spheromaks via Steady Inductive Helicity Injection (SIHI). Three injector units allow for continuous injection of helicity into a copper flux conserver in order to sustain a spheromak. Firing of the injectors with a phase difference allows finite rotation of the plasma to provide a stabilizing effect. Simulations in the MHD code NIMROD and the fluid-model code PSI-TET provide validation and a basis for interpretation of the observed experimental data. Thompson Scattering (TS) and Far Infrared (FIR) Interferometer systems allow temperature and line-averaged density measurements to be taken. An Ion Doppler Spectroscopy (IDS) system allows measurement of the plasma rotation and velocity. HIT-SI3 data has been used for validation of IDCD predictions, in particular the projected impedance of helicity injectors according to the theory. The experimental impedances have been calculated here for the first time for different HIT-SI3 regimes. Such experimental evidence will contribute to the design of future experiments employing IDCD as a current-drive mechanism. Work supported by the D.O.E., Office of Science, Office of Fusion Science.

Rise of Human Intelligence: Comments on Howard (1999).

ERIC Educational Resources Information Center

Gobet, Fernand; Campitelli, Guillermo; Waters, Andrew J.

2002-01-01

Finds several difficulties with the theory advanced by R. Howard and shows that alternative explanations relating to changes in the chess environment, including increased access to chess knowledge, offer better explanations for the increased presence of young players at top-level chess. (SLD)

What was historical about natural history? Contingency and explanation in the science of living things.

PubMed

Harrison, Peter

2016-08-01

There is a long-standing distinction in Western thought between scientific and historical modes of explanation. According to Aristotle's influential account of scientific knowledge there cannot be an explanatory science of what is contingent and accidental, such things being the purview of a descriptive history. This distinction between scientia and historia continued to inform assumptions about scientific explanation into the nineteenth century and is particularly significant when considering the emergence of biology and its displacement of the more traditional discipline of natural history. One of the consequences of this nineteenth-century transition was that while modern evolutionary theory retained significant, if often implicit, historical components, these were often overlooked as evolutionary biology sought to accommodate itself to a model of scientific explanation that involved appeals to laws of nature. These scientific aspirations of evolutionary biology sometimes sit uncomfortably with its historical dimension. This tension lies beneath recent philosophical critiques of evolutionary theory and its modes of explanation. Such critiques, however, overlook the fact that there are legitimate modes of historical explanation that do not require recourse to laws of nature. But responding to these criticisms calls for a more explicit recognition of the affinities between evolutionary biology and history. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

“What about building 7?” A social psychological study of online discussion of 9/11 conspiracy theories

PubMed Central

Wood, Michael J.; Douglas, Karen M.

2013-01-01

Recent research into the psychology of conspiracy belief has highlighted the importance of belief systems in the acceptance or rejection of conspiracy theories. We examined a large sample of conspiracist (pro-conspiracy-theory) and conventionalist (anti-conspiracy-theory) comments on news websites in order to investigate the relative importance of promoting alternative explanations vs. rejecting conventional explanations for events. In accordance with our hypotheses, we found that conspiracist commenters were more likely to argue against the opposing interpretation and less likely to argue in favor of their own interpretation, while the opposite was true of conventionalist commenters. However, conspiracist comments were more likely to explicitly put forward an account than conventionalist comments were. In addition, conspiracists were more likely to express mistrust and made more positive and fewer negative references to other conspiracy theories. The data also indicate that conspiracists were largely unwilling to apply the “conspiracy theory” label to their own beliefs and objected when others did so, lending support to the long-held suggestion that conspiracy belief carries a social stigma. Finally, conventionalist arguments tended to have a more hostile tone. These tendencies in persuasive communication can be understood as a reflection of an underlying conspiracist worldview in which the details of individual conspiracy theories are less important than a generalized rejection of official explanations. PMID:23847577

Endosymbiosis and its implications for evolutionary theory.

PubMed

O'Malley, Maureen A

2015-08-18

Historically, conceptualizations of symbiosis and endosymbiosis have been pitted against Darwinian or neo-Darwinian evolutionary theory. In more recent times, Lynn Margulis has argued vigorously along these lines. However, there are only shallow grounds for finding Darwinian concepts or population genetic theory incompatible with endosymbiosis. But is population genetics sufficiently explanatory of endosymbiosis and its role in evolution? Population genetics "follows" genes, is replication-centric, and is concerned with vertically consistent genetic lineages. It may also have explanatory limitations with regard to macroevolution. Even so, asking whether population genetics explains endosymbiosis may have the question the wrong way around. We should instead be asking how explanatory of evolution endosymbiosis is, and exactly which features of evolution it might be explaining. This paper will discuss how metabolic innovations associated with endosymbioses can drive evolution and thus provide an explanatory account of important episodes in the history of life. Metabolic explanations are both proximate and ultimate, in the same way genetic explanations are. Endosymbioses, therefore, point evolutionary biology toward an important dimension of evolutionary explanation.

Myths or theories? Alternative beliefs about HIV and AIDS in South African working class communities.

PubMed

Dickinson, David

2013-09-01

Despite three decades of public health promotion based on the scientific explanation of HIV/AIDS, alternative explanations of the disease continue to circulate. While these are seen as counter-productive to health education efforts, what is rarely analysed is their plurality and their tenacity. This article analyses the 'AIDS myths' collected by African HIV/AIDS workplace peer educators during an action research project. These beliefs about HIV/AIDS are organised, in this article, around core ideas that form the basis of 'folk' and 'lay theories' of HIV/AIDS. These constitute non-scientific explanations of HIV/AIDS, with folk theories drawing on bodies of knowledge that are independent of HIV/AIDS while lay theories are generated in response to the disease. A categorisation of alternative beliefs about HIV/AIDS is presented which comprises three folk theories - African traditional beliefs, Christian theology, and racial conspiracy - and three lay theories, all focused on avoiding HIV infection. Using this schema, the article describes how the plausibility of these alternative theories of HIV/AIDS lies not in their scientific validity, but in the robustness of the core idea at the heart of each folk or lay theory. Folk and lay theories of HIV/AIDS are also often highly palatable in that they provide hope and comfort in terms of prevention, cure, and the allocation of blame. This study argue that there is coherence and value to these alternative HIV/AIDS beliefs which should not be dismissed as ignorance, idle speculation or simple misunderstandings. A serious engagement with folk and lay theories of HIV/AIDS helps explain the continued circulation of alternative beliefs of HIV/AIDS and the slow uptake of behavioural change messages around the disease.

Incubation, Insight, and Creative Problem Solving: A Unified Theory and a Connectionist Model

ERIC Educational Resources Information Center

Helie, Sebastien; Sun, Ron

2010-01-01

This article proposes a unified framework for understanding creative problem solving, namely, the explicit-implicit interaction theory. This new theory of creative problem solving constitutes an attempt at providing a more unified explanation of relevant phenomena (in part by reinterpreting/integrating various fragmentary existing theories of…

Model of Market Share Affected by Social Media Reputation

NASA Astrophysics Data System (ADS)

Ishii, Akira; Kawahata, Yasuko; Goto, Ujo

Proposal of market theory to put the effect of social media into account is presented in this paper. The standard market share model in economics is employed as a market theory and the effect of social media is considered quantitatively using the mathematical model for hit phenomena. Using this model, we can estimate the effect of social media in market share as a simple market model simulation using our proposed method.

Applications of computerized adaptive testing (CAT) to the assessment of headache impact.

PubMed

Ware, John E; Kosinski, Mark; Bjorner, Jakob B; Bayliss, Martha S; Batenhorst, Alice; Dahlöf, Carl G H; Tepper, Stewart; Dowson, Andrew

2003-12-01

To evaluate the feasibility of computerized adaptive testing (CAT) and the reliability and validity of CAT-based estimates of headache impact scores in comparison with 'static' surveys. Responses to the 54-item Headache Impact Test (HIT) were re-analyzed for recent headache sufferers (n = 1016) who completed telephone interviews during the National Survey of Headache Impact (NSHI). Item response theory (IRT) calibrations and the computerized dynamic health assessment (DYNHA) software were used to simulate CAT assessments by selecting the most informative items for each person and estimating impact scores according to pre-set precision standards (CAT-HIT). Results were compared with IRT estimates based on all items (total-HIT), computerized 6-item dynamic estimates (CAT-HIT-6), and a developmental version of a 'static' 6-item form (HIT-6-D). Analyses focused on: respondent burden (survey length and administration time), score distributions ('ceiling' and 'floor' effects), reliability and standard errors, and clinical validity (diagnosis, level of severity). A random sample (n = 245) was re-assessed to test responsiveness. A second study (n = 1103) compared actual CAT surveys and an improved 'static' HIT-6 among current headache sufferers sampled on the Internet. Respondents completed measures from the first study and the generic SF-8 Health Survey; some (n = 540) were re-tested on the Internet after 2 weeks. In the first study, simulated CAT-HIT and total-HIT scores were highly correlated (r = 0.92) without 'ceiling' or 'floor' effects and with a substantial reduction (90.8%) in respondent burden. Six of the 54 items accounted for the great majority of item administrations (3603/5028, 77.6%). CAT-HIT reliability estimates were very high (0.975-0.992) in the range where 95% of respondents scored, and relative validity (RV) coefficients were high for diagnosis (RV = 0.87) and severity (RV = 0.89); patient-level classifications were accurate 91.3% for a diagnosis of migraine. For all three criteria of change, CAT-HIT scores were more responsive than all other measures. In the second study, estimates of respondent burden, item usage, reliability and clinical validity were replicated. The test-retest reliability of CAT-HIT was 0.79 and alternate forms coefficients ranged from 0.85 to 0.91. All correlations with the generic SF-8 were negative. CAT-based administrations of headache impact items achieved very large reductions in respondent burden without compromising validity for purposes of patient screening or monitoring changes in headache impact over time. IRT models and CAT-based dynamic health assessments warrant testing among patients with other conditions.

Symbolic Interactionism and Social Action Theory

ERIC Educational Resources Information Center

Morrione, Thomas J.

1975-01-01

An explanation and elaboration of existing theory on interaction, this article describes a point of convergence between Parsons' Voluntaristic Theory of Action and Blumer's conceptualization of Symbolic Interactionism and develops specific problems of divergence in these normative and interpretive models of interaction. (JC)

The Expertise Reversal Effect Concerning Instructional Explanations

ERIC Educational Resources Information Center

Rey, Gunter Daniel; Fischer, Andreas

2013-01-01

The expertise reversal effect occurs when learner's expertise moderates design principles derived from cognitive load theory. Although this effect is supported by numerous empirical studies, indicating an overall large effect size, the effect was never tested by inducing expertise experimentally and using instructional explanations in a…

Age and the Explanation of Crime, Revisited

ERIC Educational Resources Information Center

Sweeten, Gary; Piquero, Alex R.; Steinberg, Laurence

2013-01-01

Age is one of the most robust correlates of criminal behavior. Yet, explanations for this relationship are varied and conflicting. Developmental theories point to a multitude of sociological, psychological, and biological changes that occur during adolescence and adulthood. One prominent criminological perspective outlined by Gottfredson and…

A Self-Categorization Explanation for Opinion Consensus Perceptions

ERIC Educational Resources Information Center

Zhang, Jinguang; Reid, Scott A.

2013-01-01

The public expression of opinions (and related communicative activities) hinges upon the perception of opinion consensus. Current explanations for opinion consensus perceptions typically focus on egocentric and other biases, rather than functional cognitions. Using self-categorization theory we showed that opinion consensus perceptions flow from…

Considerations of Elder Sibling Closeness in Predicting Younger Sibling Substance Use: Social Learning versus Social Bonding Explanations

PubMed Central

Samek, Diana R.; Rueter, Martha A.

2011-01-01

Adolescent siblings are often similar in a variety of adjustment outcomes, yet little is known about the processes that explain sibling influences during adolescence. Two alternative explanations were tested, attachment (based in social bonding theory) and anaclitic identification (based in social learning theory). Hypotheses were tested using a sample of 613 adolescent sibling pairs (206 non-adopted, 407 adopted; elder sibling Mage = 16.1, younger sibling Mage = 13.8) across three sibling contexts (gender composition, age difference, and genetic similarity). Attachment explanations were supported such that the greater the perceived sibling emotional and behavioral closeness, the lower the likelihood of substance use; however, there were considerable moderating effects of sibling gender composition. Anaclitic identification explanations were not supported; closeness and elder sibling substance use did not interact to predict younger sibling substance use. Overall, this research adds to a body of work demonstrating important sibling influences on adolescent substance use. PMID:21988080

Entering Communities: Social Justice Oriented Disaster Response Counseling

ERIC Educational Resources Information Center

West-Olatunji, Cirecie; Goodman, Rachael D.

2011-01-01

Counselors need to learn how to effectively and respectfully enter into communities hit by disasters and create collaborative partnerships with community members. Using critical consciousness theory, the authors describe a humanistic, culturally responsive approach to disaster response counseling for marginalized individuals and communities and…

Rethinking the relationship between socio-economic status and health: Making the case for sociological theory in health inequality research.

PubMed

Øversveen, Emil; Rydland, Håvard T; Bambra, Clare; Eikemo, Terje A

2017-03-01

The aim of this study is to analyse previous explanations of social inequality in health and argue for a closer integration of sociological theory into future empirical research. We examine cultural-behavioural, materialist, psychosocial and life-course approaches, in addition to fundamental cause theory. Giddens' structuration theory and a neo-materialist approach, inspired by Bruno Latour, Gilles Deleuze and Felix Guattari, are proposed as ways of rethinking the causal relationship between socio-economic status and health. Much of the empirical research on health inequalities has tended to rely on explanations with a static and unidirectional view of the association between socio-economic status and health, assuming a unidirectional causal relationship between largely static categories. We argue for the use of sociological theory to develop more dynamic models that enhance the understanding of the complex pathways and mechanisms linking social structures to health.

An ecological valence theory of human color preference.

PubMed

Palmer, Stephen E; Schloss, Karen B

2010-05-11

Color preference is an important aspect of visual experience, but little is known about why people in general like some colors more than others. Previous research suggested explanations based on biological adaptations [Hurlbert AC, Ling YL (2007) Curr Biol 17:623-625] and color-emotions [Ou L-C, Luo MR, Woodcock A, Wright A (2004) Color Res Appl 29:381-389]. In this article we articulate an ecological valence theory in which color preferences arise from people's average affective responses to color-associated objects. An empirical test provides strong support for this theory: People like colors strongly associated with objects they like (e.g., blues with clear skies and clean water) and dislike colors strongly associated with objects they dislike (e.g., browns with feces and rotten food). Relative to alternative theories, the ecological valence theory both fits the data better (even with fewer free parameters) and provides a more plausible, comprehensive causal explanation of color preferences.

Environmental factors and health information technology management strategy.

PubMed

Menachemi, Nir; Shin, Dong Yeong; Ford, Eric W; Yu, Feliciano

2011-01-01

: Previous studies have provided theoretical and empirical evidence that environmental forces influence hospital strategy. : Rooted in resource dependence theory and the information uncertainty perspective, this study examined the relationship between environmental market characteristics and hospitals' selection of a health information technology (HIT) management strategy. : A cross-sectional design is used to analyze secondary data from the American Hospital Association Annual Survey, the Healthcare Information and Management Systems Society Analytics Database, and the Area Resource File. Univariate and multinomial logistic regression analyses are used. : Overall, 3,221 hospitals were studied, of which 60.9% pursed a single-vendor HIT management strategy, 28.9% pursued a best-of-suite strategy, and 10.2% used a best-of-breed strategy. Multivariate analyses controlling for hospital characteristics found that measures of environmental factors representing munificence, dynamism, and/or complexity were systematically associated with various hospital HIT management strategy use. Specifically, the number of generalist physicians per capita was positively associated with the single-vendor strategy (B = -5.64, p = .10). Hospitals in urban markets were more likely to pursue the best-of-suite strategy (B = 0.622, p < .001). Dynamism, measured as the number of managed care contracts for a given hospital, was negatively associated with the single-vendor strategy (B = 0.004, p = .049). Lastly, complexity, measured as market competition, was positively associated with the best-of-breed strategy (B = 0.623, p = .042). : By and large, environmental factors are associated with hospital HIT management strategies in mostly theoretically supported ways. Hospital leaders and policy makers interested in influencing the adoption of hospital HIT should consider how market conditions influence HIT management decisions as part of programs to promote meaningful use.

Constructing Scientific Explanations: a System of Analysis for Students' Explanations

NASA Astrophysics Data System (ADS)

de Andrade, Vanessa; Freire, Sofia; Baptista, Mónica

2017-08-01

This article describes a system of analysis aimed at characterizing students' scientific explanations. Science education literature and reform documents have been highlighting the importance of scientific explanations for students' conceptual understanding and for their understanding of the nature of scientific knowledge. Nevertheless, and despite general agreement regarding the potential of having students construct their own explanations, a consensual notion of scientific explanation has still not been reached. As a result, within science education literature, there are several frameworks defining scientific explanations, with different foci as well as different notions of what accounts as a good explanation. Considering this, and based on a more ample project, we developed a system of analysis to characterize students' explanations. It was conceptualized and developed based on theories and models of scientific explanations, science education literature, and from examples of students' explanations collected by an open-ended questionnaire. With this paper, it is our goal to present the system of analysis, illustrating it with specific examples of students' collected explanations. In addition, we expect to point out its adequacy and utility for analyzing and characterizing students' scientific explanations as well as for tracing their progression.

Interest in and reactions to genetic risk information: The role of implicit theories and self-affirmation.

PubMed

Taber, Jennifer M; Klein, William M P; Persky, Susan; Ferrer, Rebecca A; Kaufman, Annette R; Thai, Chan L; Harris, Peter R

2017-10-01

Implicit theories reflect core assumptions about whether human attributes are malleable or fixed: Incremental theorists believe a characteristic is malleable whereas entity theorists believe it is fixed. People with entity theories about health may be less likely to engage in risk-mitigating behavior. Spontaneous self-affirmation (e.g., reflecting on one's values when threatened) may lessen defensiveness and unhealthy behaviors associated with fixed beliefs, and reduce the likelihood of responding to health risk information with fixed beliefs. Across two studies conducted in the US from 2012 to 2015, we investigated how self-affirmation and implicit theories about health and body weight were linked to engagement with genetic risk information. In Study 1, participants in a genome sequencing trial (n = 511) completed cross-sectional assessments of implicit theories, self-affirmation, and intentions to learn, share, and use genetic information. In Study 2, overweight women (n = 197) were randomized to receive genetic or behavioral explanations for weight; participants completed surveys assessing implicit theories, self-affirmation, self-efficacy, motivation, and intentions. Fixed beliefs about weight were infrequently endorsed across studies (10.8-15.2%). In Study 1, participants with stronger fixed theories were less interested in learning and using genetic risk information about medically actionable disease; these associations were weaker among participants higher in self-affirmation. In Study 2, among participants given behavioral explanations for weight, stronger fixed theories about weight were associated with lower motivation and intentions to eat a healthy diet. Among participants given genetic explanations, being higher in self-affirmation was associated with less fixed beliefs. Stronger health-related fixed theories may decrease the likelihood of benefiting from genetic information, but less so for people who self-affirm. Published by Elsevier Ltd.

The Importance of Qualitative Research for Causal Explanation in Education

ERIC Educational Resources Information Center

Maxwell, Joseph A.

2012-01-01

The concept of causation has long been controversial in qualitative research, and many qualitative researchers have rejected causal explanation as incompatible with an interpretivist or constructivist approach. This rejection conflates causation with the positivist "theory" of causation, and ignores an alternative understanding of causation,…

Investigating Friendship Quality: An Exploration of Self-Control and Social Control Theories' Friendship Hypotheses

ERIC Educational Resources Information Center

Boman, John H., IV; Krohn, Marvin D.; Gibson, Chris L.; Stogner, John M.

2012-01-01

While associations with deviant peers are well understood to impact individual development, less is understood about the relationship between friendship quality and delinquency. Two criminological theories--social control theory and self-control theory--are able to offer an explanation for the latter relationship. Social control and self-control…

Theory and Contrastive Explanation in Ethnography

ERIC Educational Resources Information Center

Lichterman, Paul; Reed, Isaac Ariail

2015-01-01

We propose three interlinked ways that theory helps researchers build causal claims from ethnographic research. First, theory guides the casing and re-casing of a topic of study. Second, theoretical work helps craft a clear causal question via the construction of a contrast space of the topic of investigation. Third, the researcher uses theory to…

Oppositional Culture Theory and the Delusion of Colorblindness

ERIC Educational Resources Information Center

Berlowitz, Marvin J.; Hutchins, Brandi N.; Jenkins, Derrick J.; Mussman, Mark P.; Schneider, Carri A.

2006-01-01

Oppositional culture theory is a widely accepted explanation for disparities in academic performance between middle class Whites and middle class African Americans. The authors make the case that oppositional culture theory has its roots in cultural deficit theory popularized in the early 1960s and present a significant body of evidence to refute…

Lessons from the Canadian national health information technology plan for the United States: opinions of key Canadian experts.

PubMed

Zimlichman, Eyal; Rozenblum, Ronen; Salzberg, Claudia A; Jang, Yeona; Tamblyn, Melissa; Tamblyn, Robyn; Bates, David W

2012-01-01

To summarize the Canadian health information technology (HIT) policy experience and impart lessons learned to the US as it determines its policy in this area. Qualitative analysis of interviews with identified key stakeholders followed by an electronic survey. We conducted semi-structured interviews with 29 key Canadian HIT policy and opinion leaders and used a grounded theory approach to analyze the results. The informant sample was chosen to provide views from different stakeholder groups including national representatives and regional representatives from three Canadian provinces. Canadian informants believed that much of the current US direction is positive, especially regarding incentives and meaningful use, but that there are key opportunities for the US to emphasize direct engagement with providers, define a clear business case for them, sponsor large scale evaluations to assess HIT impact in a broad array of settings, determine standards but also enable access to resources needed for mid-course corrections of standards when issues are identified, and, finally, leverage implementation of digital imaging systems. Not all stakeholder groups were included, such as providers or patients. In addition, as in all qualitative research, a selection bias could be present due to the relatively small sample size. Based on Canadian experience with HIT policy, stakeholders identified as lessons for the US the need to increase direct engagement with providers and the importance of defining the business case for HIT, which can be achieved through large scale evaluations, and of recognizing and leveraging successes as they emerge.

Special technical services for investigation of light flash phenomena

NASA Technical Reports Server (NTRS)

1973-01-01

Details are presented of an investigation aimed at an explanation of the phenomenon of light flashes observed by Apollo crew members. The various theories considered include: penetration of the eye by cosmic particles resulting in retinal stimulation; production of phosphenes or sensations of light through ionization or excitation; appearance of heavily ionized single tracks misinterpreted as light flashes; Cerenkov radiation; and direct excitation of neural tissue by penetrating cosmic rays. It is concluded that the latter two theories are the likeliest mechanisms for the development of a definitive explanation.

Age and ethnic differences in cold weather and contagion theories of colds and flu.

PubMed

Sigelman, Carol K

2012-02-01

Age and ethnic group differences in cold weather and contagion or germ theories of infectious disease were explored in two studies. A cold weather theory was frequently invoked to explain colds and to a lesser extent flu but became less prominent with age as children gained command of a germ theory of disease. Explanations of how contact with other people causes disease were more causally sophisticated than explanations of how cold weather causes it. Finally, Mexican American and other minority children were more likely than European American children to subscribe to cold weather theories, a difference partially but not wholly attributable to ethnic group differences in parent education. Findings support the value of an intuitive or naïve theories perspective in understanding developmental and sociocultural differences in concepts of disease and in planning health education to help both children and their parents shed misconceptions so that they can focus on effective preventive actions.

Auger-electron cascades, charge potential and microdosimetry of iodine-125.

PubMed

Booz, J; Paretzke, H G; Pomplun, E; Olko, P

1987-01-01

This paper is a contribution to the microdosimetry of I-125. It shows microdosimetric spectra of individual and average disintegrations of I-125 for various target sizes and gives evidence for the relative contributions of energy-deposition events of low and high LET. It further presents information on the relative efficiencies of Auger-electrons and multiple charges in terms of local energy deposition, e.g. to model targets of DNA, and discusses their radiobiological implications, e.g. the microdosimetric understanding of the different efficiencies of specific and random incorporations of I-125. When I-125 is specifically incorporated into DNA, most of the energy deposition events are very large, e.g. above 40 keV/micron for a simulated target volume of 20 nm diameter, regardless of the number and energy of Auger electrons emitted. Therefore it is not necessary, for the discussion of the radiobiological implications, to distinguish between different classes of disintegrations. For unspecific, homogeneous incorporation of I-125 somewhere into tissue, about 20% of the dose to critical targets of 25 nm diameter is made up by disintegrations that happen to occur within these targets. When assuming that other critical targets and target structures can be neglected, this part of the dose will be equally effective as in the case of specific incorporation of I-125 into such target models. In addition, there are the normal, low-LET radiation effects from the other, 80% large fraction of the dose. With this information, for the biological systems and end points for which a short section of the elemental chromatine fiber can be taken as the relevant critical target, it is shown that the expected D37 value for homogeneous unspecific incorporation of I-125 can be estimated when the D37 for specific incorporation in DNA is known. For an example calculation, the estimated D37-value for nonspecific, homogeneous incorporation of I-125 would be about half as effective as specifically incorporated I-125. Thus, the microdosimetric data of the present work show that a high efficiency of homogeneous incorporation of I-125 into the cell nucleus is not necessarily in contradiction with the idea of I-125 disintegrations inside the DNA being the main cause of radiation action.

The validity and value of inclusive fitness theory

PubMed Central

Bourke, Andrew F. G.

2011-01-01

Social evolution is a central topic in evolutionary biology, with the evolution of eusociality (societies with altruistic, non-reproductive helpers) representing a long-standing evolutionary conundrum. Recent critiques have questioned the validity of the leading theory for explaining social evolution and eusociality, namely inclusive fitness (kin selection) theory. I review recent and past literature to argue that these critiques do not succeed. Inclusive fitness theory has added fundamental insights to natural selection theory. These are the realization that selection on a gene for social behaviour depends on its effects on co-bearers, the explanation of social behaviours as unalike as altruism and selfishness using the same underlying parameters, and the explanation of within-group conflict in terms of non-coinciding inclusive fitness optima. A proposed alternative theory for eusocial evolution assumes mistakenly that workers' interests are subordinate to the queen's, contains no new elements and fails to make novel predictions. The haplodiploidy hypothesis has yet to be rigorously tested and positive relatedness within diploid eusocial societies supports inclusive fitness theory. The theory has made unique, falsifiable predictions that have been confirmed, and its evidence base is extensive and robust. Hence, inclusive fitness theory deserves to keep its position as the leading theory for social evolution. PMID:21920980

The validity and value of inclusive fitness theory.

PubMed

Bourke, Andrew F G

2011-11-22

Social evolution is a central topic in evolutionary biology, with the evolution of eusociality (societies with altruistic, non-reproductive helpers) representing a long-standing evolutionary conundrum. Recent critiques have questioned the validity of the leading theory for explaining social evolution and eusociality, namely inclusive fitness (kin selection) theory. I review recent and past literature to argue that these critiques do not succeed. Inclusive fitness theory has added fundamental insights to natural selection theory. These are the realization that selection on a gene for social behaviour depends on its effects on co-bearers, the explanation of social behaviours as unalike as altruism and selfishness using the same underlying parameters, and the explanation of within-group conflict in terms of non-coinciding inclusive fitness optima. A proposed alternative theory for eusocial evolution assumes mistakenly that workers' interests are subordinate to the queen's, contains no new elements and fails to make novel predictions. The haplodiploidy hypothesis has yet to be rigorously tested and positive relatedness within diploid eusocial societies supports inclusive fitness theory. The theory has made unique, falsifiable predictions that have been confirmed, and its evidence base is extensive and robust. Hence, inclusive fitness theory deserves to keep its position as the leading theory for social evolution.

The Interactive Attribution of School Success in Multi-Ethnic Schools

ERIC Educational Resources Information Center

de Haan, Mariette; Wissink, Inge

2013-01-01

The study shows how explanations for school success are expressed and dialogically constructed during teacher-parent conferences at school. Attribution theory is used to conceptualize the various explanations for school success that were expressed. However, instead of only looking at attributions as beliefs which individuals or groups "have", the…

I Dream of J.J., or Affordances and Motion Pictures.

ERIC Educational Resources Information Center

Anderson, Joseph D.

1995-01-01

Categorizes attempts to account for how viewers garner meanings from motion pictures as either semiotic, realist, or conventionalist. Proposes an alternative explanation based on J. J. Gibson's ecological theory of perception. Offers his concept of "affordances" as the key to an explanation of how meanings in motion pictures are…

An Application of Number Theory to Cryptology.

ERIC Educational Resources Information Center

Snow, Joanne R.

1989-01-01

Discussed is an application of number theory to cryptology that can be used with secondary school students. Background on the topics is given first, followed by an explanation for use of the topic. (MNS)

Microdose analysis of ion strikes on SRAM cells

NASA Astrophysics Data System (ADS)

Scheick, L.

2003-12-01

A method of measuring the effect from exposure to highly localized ionizing radiation on microstructures is described. The voltage at which a commercial SRAM cell cannot hold a programmed state changes with microdose. The microdose distribution across the array, in addition to the analysis of the occurrence of anomalous shifts in operating bias due to rare, large energy-deposition events is studied. The effect of multiple hits on a SRAM cell is presented. A general theory on multiple hits from which basic device parameters can be extracted is presented. SPICE, as well as analysis of basic device physics, is used to analyze the damage to individual transistors and the response of a SRAM cell.

How people explain their own and others’ behavior: a theory of lay causal explanations

PubMed Central

Böhm, Gisela; Pfister, Hans-Rüdiger

2015-01-01

A theoretical model is proposed that specifies lay causal theories of behavior; and supporting experimental evidence is presented. The model’s basic assumption is that different types of behavior trigger different hypotheses concerning the types of causes that may have brought about the behavior. Seven categories are distinguished that are assumed to serve as both behavior types and explanation types: goals, dispositions, temporary states such as emotions, intentional actions, outcomes, events, and stimulus attributes. The model specifies inference rules that lay people use when explaining behavior (actions are caused by goals; goals are caused by higher order goals or temporary states; temporary states are caused by dispositions, stimulus attributes, or events; outcomes are caused by actions, temporary states, dispositions, stimulus attributes, or events; events are caused by dispositions or preceding events). Two experiments are reported. Experiment 1 showed that free-response explanations followed the assumed inference rules. Experiment 2 demonstrated that explanations which match the inference rules are generated faster and more frequently than non-matching explanations. Together, the findings support models that incorporate knowledge-based aspects into the process of causal explanation. The results are discussed with respect to their implications for different stages of this process, such as the activation of causal hypotheses and their subsequent selection, as well as with respect to social influences on this process. PMID:25741306

Disintegration, Recognition, and Violence: A Theoretical Perspective

ERIC Educational Resources Information Center

Heitmeyer, Wilhelm; Anhut, Reimund

2008-01-01

The literature explaining deviance, criminality, or violence offers a broad spectrum of approaches in criminology and sociology. Mostly the theories focus on specific levels of explanation like the macrolevel (for example, strain theories) or the microlevel (for example, self-control theory). This article presents a relatively new theoretical…

Teaching Interactionist Gender Theory through Speed Dating

ERIC Educational Resources Information Center

Messinger, Adam M.

2015-01-01

Few evaluated classroom exercises to date have addressed one of the most cited and compelling explanations of gender formation over the life course: interactionist gender theory. This theory posits that people actively "do" or "perform" their gender in every interaction, and as such, they often subconsciously reshape their…

Violent aggression predicted by multiple pre-adult environmental hits.

PubMed

Mitjans, Marina; Seidel, Jan; Begemann, Martin; Bockhop, Fabian; Moya-Higueras, Jorge; Bansal, Vikas; Wesolowski, Janina; Seelbach, Anna; Ibáñez, Manuel Ignacio; Kovacevic, Fatka; Duvar, Oguzhan; Fañanás, Lourdes; Wolf, Hannah-Ulrike; Ortet, Generós; Zwanzger, Peter; Klein, Verena; Lange, Ina; Tänzer, Andreas; Dudeck, Manuela; Penke, Lars; van Elst, Ludger Tebartz; Bittner, Robert A; Schmidmeier, Richard; Freese, Roland; Müller-Isberner, Rüdiger; Wiltfang, Jens; Bliesener, Thomas; Bonn, Stefan; Poustka, Luise; Müller, Jürgen L; Arias, Bárbara; Ehrenreich, Hannelore

2018-05-24

Early exposure to negative environmental impact shapes individual behavior and potentially contributes to any mental disease. We reported previously that accumulated environmental risk markedly decreases age at schizophrenia onset. Follow-up of matched extreme group individuals (≤1 vs. ≥3 risks) unexpectedly revealed that high-risk subjects had >5 times greater probability of forensic hospitalization. In line with longstanding sociological theories, we hypothesized that risk accumulation before adulthood induces violent aggression and criminal conduct, independent of mental illness. We determined in 6 independent cohorts (4 schizophrenia and 2 general population samples) pre-adult risk exposure, comprising urbanicity, migration, physical and sexual abuse as primary, and cannabis or alcohol as secondary hits. All single hits by themselves were marginally associated with higher violent aggression. Most strikingly, however, their accumulation strongly predicted violent aggression (odds ratio 10.5). An epigenome-wide association scan to detect differential methylation of blood-derived DNA of selected extreme group individuals yielded overall negative results. Conversely, determination in peripheral blood mononuclear cells of histone-deacetylase1 mRNA as 'umbrella mediator' of epigenetic processes revealed an increase in the high-risk group, suggesting lasting epigenetic alterations. Together, we provide sound evidence of a disease-independent unfortunate relationship between well-defined pre-adult environmental hits and violent aggression, calling for more efficient prevention.

Discovering Authorities and Hubs in Different Topological Web Graph Structures.

ERIC Educational Resources Information Center

Meghabghab, George

2002-01-01

Discussion of citation analysis on the Web considers Web hyperlinks as a source to analyze citations. Topics include basic graph theory applied to Web pages, including matrices, linear algebra, and Web topology; and hubs and authorities, including a search technique called HITS (Hyperlink Induced Topic Search). (Author/LRW)

The changing features of the body-mind problem.

PubMed

Agassi, Joseph

2007-01-01

The body-mind problem invites scientific study, since mental events are repeated and repeatable and invite testable explanations. They seemed troublesome because of the classical theory of substance that failed to solve its own central problems. These are soluble with the aid of the theory of the laws of nature, particularly in its emergentist version [Bunge, M., 1980. The Body-mind Problem, Pergamon, Oxford] that invites refutable explanations [Popper, K.R., 1959. The Logic of Scientific Discovery, Hutchinson, London]. The view of mental properties as emergent is a modification of the two chief classical views, materialism and dualism. As this view invites testable explanations of events of the inner world, it is better than the quasi-behaviorist view of self-awareness as computer-style self-monitoring [Minsky, M., Laske, O., 1992. A conversation with Marvin Minsky. AI Magazine 13 (3), 31-45].

Characterizing High School Students' Written Explanations in Biology Laboratories

NASA Astrophysics Data System (ADS)

Peker, Deniz; Wallace, Carolyn S.

2011-03-01

The purpose of this qualitative interpretive research study was to examine high school students' written scientific explanations during biology laboratory investigations. Specifically, we characterized the types of epistemologies and forms of reasoning involved in students' scientific explanations and students' perceptions of scientific explanations. Sixteen students from a rural high school in the Southeastern United States were the participants of this research study. The data consisted of students' laboratory reports and individual interviews. The results indicated that students' explanations were primarily based on first-hand knowledge gained in the science laboratories and mostly representing procedural recounts. Most students did not give explanations based on a theory or a principle and did not use deductive reasoning in their explanations. The students had difficulties explaining phenomena that involved intricate cause-effect relationships. Students perceived scientific explanation as the final step of a scientific inquiry and as an account of what happened in the inquiry process, and held a constructivist-empiricist view of scientific explanations. Our results imply the need for more explicit guidance to help students construct better scientific explanations and explicit teaching of the explanatory genre with particular focus on theoretical and causal explanations.

Stochastic game theory: for playing games, not just for doing theory.

PubMed

Goeree, J K; Holt, C A

1999-09-14

Recent theoretical advances have dramatically increased the relevance of game theory for predicting human behavior in interactive situations. By relaxing the classical assumptions of perfect rationality and perfect foresight, we obtain much improved explanations of initial decisions, dynamic patterns of learning and adjustment, and equilibrium steady-state distributions.

Organizational Theory and Student Cheating: Explanation, Responses, and Strategies

ERIC Educational Resources Information Center

Gallant, Tricia Bertram; Drinan, Patrick

2006-01-01

Studies have described and analyzed the problem of student cheating as well as institutional responses to the problem. However, organizational theory has been neglected. Viewing student cheating and institutional responses through the lens of organizational theory can inform strategy and instill fresh approaches to the management of the problem.

Examining Hypermedia Learning: The Role of Cognitive Load and Self-Regulated Learning

ERIC Educational Resources Information Center

Moos, Daniel

2013-01-01

Distinct theoretical perspectives, Cognitive Load Theory and Self-Regulated Learning (SRL) theory, have been used to examine individual differences the challenges faced with hypermedia learning. However, research has tended to use these theories independently, resulting in less robust explanations of hypermedia learning. This study examined the…

Adult Learning Theory: A Primer. Information Series.

ERIC Educational Resources Information Center

Baumgartner, Lisa M.; Lee, Ming-Yeh; Birden, Susan; Flowers, Doris

The purpose of this monograph is to serve as a primer for practitioners on the foundational theories of adult learning. It begins with an explanation two lenses through which learning theory is viewed: behaviorism and constructivism. The next section defines andragogy and delineates Knowles's five assumptions about adult learners. This is followed…

Extending Sociocultural Theory to Group Creativity

ERIC Educational Resources Information Center

Sawyer, Keith

2012-01-01

Sociocultural theory focuses on group processes through time, and argues that group phenomena cannot be reduced to explanation in terms of the mental states or actions of the participating individuals. This makes sociocultural theory particularly useful in the analysis of group creativity and group learning, because both group creativity and group…

Social Learning Theory and Developmental Psychology: The Legacies of Robert Sears and Albert Bandura.

ERIC Educational Resources Information Center

Grusec, Joan E.

1992-01-01

Social learning theory is evaluated from a historical perspective that goes up to the present. Sears and others melded psychoanalytic and stimulus-response learning theory into a comprehensive explanation of human behavior. Bandura emphasized cognitive and information-processing capacities that mediate social behavior. (LB)

Prevention of Child Abuse: Theory, Myth, Practice.

ERIC Educational Resources Information Center

Newberger, Eli H.; Newberger, Carolyn Moore

Child abuse is discussed in terms of theory which when realized may lead to more effective primary and secondary prevention efforts. Theoretical explanations of child abuse are classified as either unitary or interactive. Unitary theories (psychological, sociological, and legal views of behavior) are considered deficient; none is capable of…

Polarization and Persuasion: Integrating the Elaboration Likelihood Model with Explanations of Group Polarization.

ERIC Educational Resources Information Center

Mongeau, Paul A.

Interest has recently focused on group polarization as a function of attitude processes. Several recent reviewers have challenged polarization researchers to integrate the explanations of polarization to existing theories of attitude change. This review suggests that there exists a clear similarity between the social comparison and persuasive…

A Self-Categorization Explanation for the Third-Person Effect

ERIC Educational Resources Information Center

Reid, Scott A.; Hogg, Michael A.

2005-01-01

Three studies tested a self-categorization theory explanation for the third-person effect. In Study 1 (N = 49) undergraduate students judged the influence of the "National Enquirer," "Wall Street Journal," and TV show "Friends" on themselves, relative to low- and high-status outgroup members, and other undergraduate students. The profile of first-…

Liberation and Economic Marginalization: A Reformulation and Test of (Formerly?) Competing Models

ERIC Educational Resources Information Center

Hunnicutt, Gwen; Broidy, Lisa M.

2004-01-01

This study reconceptualizes and tests liberation and economic marginality hypotheses as complementary explanations for female offending patterns. Both explanations are relevant in explaining female crime, but need to be reframed as interacting forces not opposing theories. It is suggested that economic marginality is in part a consequence of…

Nagel on reduction.

PubMed

Sarkar, Sahotra

2015-10-01

This paper attempts a critical reappraisal of Nagel's (1961, 1970) model of reduction taking into account both traditional criticisms and recent defenses. This model treats reduction as a type of explanation in which a reduced theory is explained by a reducing theory after their relevant representational items have been suitably connected. In accordance with the deductive-nomological model, the explanation is supposed to consist of a logical deduction. Nagel was a pluralist about both the logical form of the connections between the reduced and reducing theories (which could be conditionals or biconditionals) and their epistemological status (as analytic connections, conventions, or synthetic claims). This paper defends Nagel's pluralism on both counts and, in the process, argues that the multiple realizability objection to reductionism is misplaced. It also argues that the Nagel model correctly characterizes reduction as a type of explanation. However, it notes that logical deduction must be replaced by a broader class of inferential techniques that allow for different types of approximation. Whereas Nagel (1970), in contrast to his earlier position (1961), recognized the relevance of approximation, he did not realize its full import for the model. Throughout the paper two case studies are used to illustrate the arguments: the putative reduction of classical thermodynamics to the kinetic theory of matter and that of classical genetics to molecular biology. Copyright © 2015. Published by Elsevier Ltd.

The many roles of "explanation" in science education: a case study

NASA Astrophysics Data System (ADS)

Rocksén, Miranda

2016-12-01

In this paper the role of explanations is discussed in relation to possible consequences originating in the polysemy of the word explanation. The present study is a response to conceptual confusions that have arisen in the intersection between theory and practice, and between science education literature and communication in authentic science classroom settings. Science classroom communication is examined in terms of one teacher's word use during eleven lessons about evolution. The study contributes empirical examples of how disciplinary norms of valid explanations are manifested in science classroom communication. A dialogical analysis shows how the teacher provides three conversational structures: asking for acts of explanation, providing opportunities to talk about what explanations are in this context and providing opportunities to talk about explanations constructed by students. These three structures facilitate the process of learning how to evaluate and justify explanations. Three potential meanings of the word "explanation" are pointed to: an everyday meaning, a pedagogical-professional meaning and a scientific meaning of the word. It is suggested that the co-existence of these three potential meanings has communicative consequences in science education.

Measures and Interpretations of Vigilance Performance: Evidence Against the Detection Criterion

NASA Technical Reports Server (NTRS)

Balakrishnan, J. D.

1998-01-01

Operators' performance in a vigilance task is often assumed to depend on their choice of a detection criterion. When the signal rate is low this criterion is set high, causing the hit and false alarm rates to be low. With increasing time on task the criterion presumably tends to increase even further, thereby further decreasing the hit and false alarm rates. Virtually all of the empirical evidence for this simple interpretation is based on estimates of the bias measure Beta from signal detection theory. In this article, I describe a new approach to studying decision making that does not require the technical assumptions of signal detection theory. The results of this new analysis suggest that the detection criterion is never biased toward either response, even when the signal rate is low and the time on task is long. Two modifications of the signal detection theory framework are considered to account for this seemingly paradoxical result. The first assumes that the signal rate affects the relative sizes of the variances of the information distributions; the second assumes that the signal rate affects the logic of the operator's stopping rule. Actual or potential applications of this research include the improved training and performance assessment of operators in areas such as product quality control, air traffic control, and medical and clinical diagnosis.

Learned Helplessness as a Schedule-Shift Effect.

ERIC Educational Resources Information Center

McReynolds, William T.

1980-01-01

The essentials of learned helplessness theory are described and supporting evidence surveyed. The explanation Seligman and Maier give for these findings is critically analyzed. A schedule-shift discrimination theory of learned helplessness effects is also discussed. (Author)

The challenge of instinctive behaviour and Darwin's theory of evolution.

PubMed

Gordillo-García, Alejandro

2016-03-01

In the Origin of Species (1859), Darwin argued that his revolutionary theory of evolution by natural selection represented a significant breakthrough in the understanding of instinctive behaviour. However, many aspects in the development of his thinking on behavioural phenomena indicate that the explanation of this particular organic feature was by no means an easy one, but that it posed an authentic challenge - something that Darwin himself always recognized. This paper explores Darwin's treatment of instincts within his theory of natural selection. Particular attention is given to elucidate how he tackled the difficulties of explaining instincts as evolving mental features. He had to explain and demonstrate its inheritance, variation, and gradual accumulation within populations. The historical and philosophical aspects of his theory are highlighted, as well as his study of the case in which the explanation of instincts represented a 'special difficulty'; that is, the sterile castes of social insects. Copyright © 2016 Elsevier Ltd. All rights reserved.

Theory of mind and central coherence in adults with high-functioning autism or Asperger syndrome.

PubMed

Beaumont, Renae; Newcombe, Peter

2006-07-01

The study investigated theory of mind and central coherence abilities in adults with high-functioning autism (HFA) or Asperger syndrome (AS) using naturalistic tasks. Twenty adults with HFA/AS correctly answered significantly fewer theory of mind questions than 20 controls on a forced-choice response task. On a narrative task, there were no differences in the proportion of mental state words between the two groups, although the participants with HFA/AS were less inclined to provide explanations for characters' mental states. No between-group differences existed on the central coherence questions of the forced-choice response task, and the participants with HFA/AS included an equivalent proportion of explanations for non-mental state phenomena in their narratives as did controls. These results support the theory of mind deficit account of autism spectrum disorders, and suggest that difficulties in mental state attribution cannot be exclusively attributed to weak central coherence.

An ecological valence theory of human color preference

PubMed Central

Palmer, Stephen E.; Schloss, Karen B.

2010-01-01

Color preference is an important aspect of visual experience, but little is known about why people in general like some colors more than others. Previous research suggested explanations based on biological adaptations [Hurlbert AC, Ling YL (2007) Curr Biol 17:623–625] and color-emotions [Ou L-C, Luo MR, Woodcock A, Wright A (2004) Color Res Appl 29:381–389]. In this article we articulate an ecological valence theory in which color preferences arise from people’s average affective responses to color-associated objects. An empirical test provides strong support for this theory: People like colors strongly associated with objects they like (e.g., blues with clear skies and clean water) and dislike colors strongly associated with objects they dislike (e.g., browns with feces and rotten food). Relative to alternative theories, the ecological valence theory both fits the data better (even with fewer free parameters) and provides a more plausible, comprehensive causal explanation of color preferences. PMID:20421475

Krashen's Five Proposals on Language Learning: Are They Valid in Libyan EFL Classes

ERIC Educational Resources Information Center

Abukhattala, Ibrahim

2013-01-01

The most remarkable theory which aims to offer an overall explanation for SLA is Krashen's Monitor Theory. As documented by the professional literature, although it has received a great deal of criticism, this theory has had a great influence on all aspect of second language research and teaching since the 1980s. Krashen's theory seems to be…

[The neurodynamic core of consciousness and neural Darwinism].

PubMed

Ibáñez, A

In the last decades, the scientific study of consciousness in the scope of the cognitive neurosciences can be considered one of the greatest challenges of contemporary science. The Gerald Edelman theory of consciousness is one of the most promising and controversial perspectives. This theory stands out by its approach to topics usually rejected by other neurophysiologic theories of consciousness, as the case of the neurophysiologic explanation of qualia. The goal of this paper is to review the dynamic core theory of consciousness, presenting the main features of the theory, analyzing the explanation strategies, their empirical extensions, and elaborating some critical considerations about the possibility of the neuroscientific study of qualia. The central and additional theoretical components are analyzed, emphasizing its ontological, restrictive and explanatory assumptions. The properties of conscious phenomena and their cerebral correlates as advanced by the theory are described, and finally its experiments and empirical extensions are examined. The explanatory strategies of the theory are analyzed, based on conceptual isomorphism between the phenomenological properties and the neurophysiological and mathematical measures. Some criticisms could be raised about the limitations of the dynamic core theory, especially regarding its account of the so-called 'hard problem' of consciousness or qualia.

[Interpretative method as a synthesis of explicative, teleologic and analogic models].

PubMed

Yáñez Cortés, R

1980-06-01

To establish the basis of the interpretative method is congruous with finding a solid basis--epistemologically speaking--to the analytic theory. This basis would be the means to transform this theory into a real science with its necessary adecuation among method, act and object of knowledge. It is only from a scientific stand that the psychoanalytic theory will be able to face successfully the reductionisms that menace it, be it the biologist-naturalism with its explanations of the psychic phenomena by means of mechanisms and biologic models or be it the speculative ideologies with their nucleus of technical praxis which make it impossible for the social-factic sciences to become real sciences. We propose as interpretative method the union of two models: the teleologic one which makes possible the appearance of intelligible, contingent and variable explanations between an antecedent and a consequent on one side, and on the other, the analogic model with its two moments: the comparative and the symbolic one. These moments makes possible the comparison and the union between antecedent and consequent baring in mind the "natural" ambiguity of the subject-object in question. The principal objective of the method--as a regulative idea in the Kantian sense--would be the search of univocity as regards the choice of one and only one sense from all the possible senses that "explain" the motive relationship or motive-end relationship in order to make the interpretation scientific. This status of scientificity should obey the rules of explanation: that the interpretations be derived effectively from the presupposed theory, that they really explain what they claim to explain, that they are not contradictory or contrary in the same ontologic level. We postulate that the synthesis of the two mentioned models, the teleologic-explanative and the analogic one allows us to find a possibility to make clear the "dark" sense of the noun interpretation and in this way the factibility of speaking of an interpretative method that develops the real concrete object by producing the formal and abstract one--which for us is the behaviour of the subject--. In this way the interpretations come to be teleological explanations overdetermined by an analogical relationship. This means that they produce the formal and abstract object -the method--which is in itself an intelligible, continguent and variable relationship between an antecedent and a consequent permitting in this way the emergence of a symbolic comparison to explain the real concrete. The symbolic explanations and comparisons are strictly derived from the presupposed theory, the theoretical body of psychoanalysis.

How the World Gains Understanding of a Planet: Analysis of Scientific Understanding in Earth Sciences and of the Communication of Earth-Scientific Explanation

NASA Astrophysics Data System (ADS)

Voute, S.; Kleinhans, M. G.; de Regt, H.

2010-12-01

A scientific explanation for a phenomenon is based on relevant theory and initial and background conditions. Scientific understanding, on the other hand, requires intelligibility, which means that a scientist can recognise qualitative characteristic consequences of the theory without doing the actual calculations, and apply it to develop further explanations and predictions. If explanation and understanding are indeed fundamentally different, then it may be possible to convey understanding of earth-scientific phenomena to laymen without the full theoretical background. The aim of this thesis is to analyze how scientists and laymen gain scientific understanding in Earth Sciences, based on the newest insights in the philosophy of science, pedagogy, and science communication. All three disciplines have something to say about how humans learn and understand, even if at very different levels of scientists, students, children or the general public. If different disciplines with different approaches identify and quantify the same theory in the same manner, then there is likely to be something “real” behind the theory. Comparing methodology and learning styles of the different disciplines within the Earth Sciences and by critically analyze earth-scientific exhibitions in different museums may provide insight in the different approaches for earth-scientific explanation and communication. In order to gain earth-scientific understanding, a broad suite of tools is used, such as maps and images, symbols and diagrams, cross-sections and sketches, categorization and classification, modelling, laboratory experiments, (computer) simulations and analogies, remote sensing, and fieldwork. All these tools have a dual nature, containing both theoretical and embodied components. Embodied knowledge is created by doing the actual modelling, intervening in experiments and doing fieldwork. Scientific practice includes discovery and exploration, data collection and analyses, verification or falsification and conclusions that must be well grounded and argued. The intelligibility of theories is improved by the combination of these two types of understanding. This is also attested by the fact that both theoretical and embodied skills are considered essential for the training of university students at all levels. However, from surprised and confounded reactions of the public to natural disasters it appears that just showing scientific results is not enough to convey the scientific understanding to the public. By using the tools used by earth scientists to develop explanations and achieve understanding, laymen could achieve understanding as well without rigorous theoretical training. We are presently investigating in science musea whether engaging the public in scientific activities based on embodied skills leads to understanding of earth-scientific phenomena by laymen.

[Medical Applications of the PHITS Code I: Recent Improvements and Biological Dose Estimation Model].

PubMed

Sato, Tatsuhiko; Furuta, Takuya; Hashimoto, Shintaro; Kuga, Naoya

2015-01-01

PHITS is a general purpose Monte Carlo particle transport simulation code developed through the collaboration of several institutes mainly in Japan. It can analyze the motion of nearly all radiations over wide energy ranges in 3-dimensional matters. It has been used for various applications including medical physics. This paper reviews the recent improvements of the code, together with the biological dose estimation method developed on the basis of the microdosimetric function implemented in PHITS.

Effectiveness of the use of question-driven levels of inquiry based instruction (QD-LOIBI) assisted visual multimedia supported teaching material on enhancing scientific explanation ability senior high school students

NASA Astrophysics Data System (ADS)

Suhandi, A.; Muslim; Samsudin, A.; Hermita, N.; Supriyatman

2018-05-01

In this study, the effectiveness of the use of Question-Driven Levels of Inquiry Based Instruction (QD-LOIBI) assisted visual multimedia supported teaching materials on enhancing senior high school students scientific explanation ability has been studied. QD-LOIBI was designed by following five-levels of inquiry proposed by Wenning. Visual multimedia used in teaching materials included image (photo), virtual simulation and video phenomena. QD-LOIBI assisted teaching materials supported by visual multimedia were tried out on senior high school students at one high school in one district in West Java. A quasi-experiment method with design one experiment group (n = 31) and one control group (n = 32) were used. Experimental group were given QD-LOIBI assisted teaching material supported by visual multimedia, whereas the control group were given QD-LOIBI assisted teaching materials not supported visual multimedia. Data on the ability of scientific explanation in both groups were collected by scientific explanation ability test in essay form concerning kinetic gas theory concept. The results showed that the number of students in the experimental class that has increased the category and quality of scientific explanation is greater than in the control class. These results indicate that the use of multimedia supported instructional materials developed for implementation of QD-LOIBI can improve students’ ability to provide explanations supported by scientific evidence gained from practicum activities and applicable concepts, laws, principles or theories.

Cognitive Development of Fourth Graders in a High-Stakes State.

ERIC Educational Resources Information Center

Aagaard, Lola; Boram, Robert

Jean Piaget's classic theory of cognitive development would imply that the higher-order items on the Kentucky state assessment would only be possible for students well into concrete operations or beginning formal operations. The implication would be that Kentucky fourth graders who are not fully concrete yet may be hitting a developmental ceiling…

Cournot Competition and Hit-and-Run Entry and Exit in a Teaching Experiment

ERIC Educational Resources Information Center

Gachter, Simon; Thoni, Christian; Tyran, Jean-Robert

2006-01-01

Instructors can use a computerized experiment to introduce students to imperfect competition in courses on introductory economics, industrial organization, game theory, and strategy and management. In addition to introducing students to strategic thinking in general, the experiment serves to demonstrate that profits of a firm fall as the number of…

Investigating Strength and Frequency Effects in Recognition Memory Using Type-2 Signal Detection Theory

ERIC Educational Resources Information Center

Higham, Philip A.; Perfect, Timothy J.; Bruno, Davide

2009-01-01

Criterion- versus distribution-shift accounts of frequency and strength effects in recognition memory were investigated with Type-2 signal detection receiver operating characteristic (ROC) analysis, which provides a measure of metacognitive monitoring. Experiment 1 demonstrated a frequency-based mirror effect, with a higher hit rate and lower…

Markov Processes: Exploring the Use of Dynamic Visualizations to Enhance Student Understanding

ERIC Educational Resources Information Center

Pfannkuch, Maxine; Budgett, Stephanie

2016-01-01

Finding ways to enhance introductory students' understanding of probability ideas and theory is a goal of many first-year probability courses. In this article, we explore the potential of a prototype tool for Markov processes using dynamic visualizations to develop in students a deeper understanding of the equilibrium and hitting times…

The Expansion of Two-Year Colleges: Tests of Institutional and Political Economy Theories in a Dynamic Model.

ERIC Educational Resources Information Center

Blau, Judith R.; And Others

Traditional theoretical explanations for the rate of expansion of educational institutions have included the "organizational ecology" model of new foundings as a function of population density, the "institutional theory" argument that foundings are responsive to societal/consumer demand, and theories of political economy which describe foundings…

Dodging the Dangers of Reductionism: Some Thoughts on Recent Feminist Theory.

ERIC Educational Resources Information Center

Smith, Joan

This paper identifies major theories prevalent in recent feminist scholarship, discusses biases inherent in these theories, and offers an original theoretical explanation for women's social and economic status. The major objective is to contribute to the body of feminist thought by exposing the biased conceptual tools used by many researchers to…

Mission Incomplete: The U.S. Army’s Unsuccessful Implementation of Stability Operations in Iraq

DTIC Science & Technology

2011-06-01

balance of power theory (which Posen argues) are not sufficient explanation for that change.19 Avant says that institutional theory provides a better...to be focus on budgets to control the military.”23 Although Avant uses institutional theory to explain civil-military relations regarding military

The Inexpressive Male: Functional-Conflict and Role Theory as Contrasting Explanations.

ERIC Educational Resources Information Center

Balswick, Jack

1979-01-01

Compares functional-conflict and role theory perspectives in their ability to explain male inexpressiveness. The role theory approach incorporates the individual and the social structure in explaining male inexpressiveness. Change in male expressiveness can be expected if males are encouraged to devote more time and energy to emotionally laden…

Cognitive Type Theory & Learning Style, A Teacher's Guide.

ERIC Educational Resources Information Center

Mamchur, Carolyn

This guide provides a practical explanation of cognitive type theory and learning style that will help teachers meet students' needs and discover their own strengths as teachers and colleagues. The introduction provides an overview of the book from the perspective of a high school classroom teacher. Part One introduces the theory of psychological…

Seeking the General Explanation: A Test of Inductive Activities for Learning and Transfer

ERIC Educational Resources Information Center

Shemwell, Jonathan T.; Chase, Catherine C.; Schwartz, Daniel L.

2015-01-01

Evaluating the relation between evidence and theory should be a central activity for science learners. Evaluation comprises both hypothetico-deductive analysis, where theory precedes evidence, and inductive synthesis, where theory emerges from evidence. There is mounting evidence that induction is an especially good way to help learners grasp the…

Task and socioemotional behaviors of physicians: a test of reciprocity and social interaction theories in analogue physician-patient encounters.

PubMed

Roberts, C A; Aruguete, M S

2000-02-01

The purpose of the present study is to assess social interaction and reciprocity theories as explanations for patient responses to a physician in a medical consultation. Social interaction theory predicts that patients mostly recognize and react to socioemotional behavior of their physicians due to a lack of understanding of physician task behaviors or a preoccupation with anxiety. Reciprocity theory predicts that patients recognize socioemotional and task behaviors of their physicians, and they respond to these behaviors in thematically similar ways. We examined these hypotheses by having subjects view one of four videotapes which varied in physician task behavior (thorough or minimum levels of explanation of etiology, symptoms, and treatment) and physician socioemotional behavior (high or low levels of concern and affection displayed verbally and non-verbally). Results supported the general proposition of social interaction theory in that high levels of socioemotional behavior of the physician increased measures of patient self-disclosure, trust, satisfaction, and likelihood of recommending the physician. Physician task behavior had no effect on patient response to the physician, a finding inconsistent with reciprocity theory.

An Explanation of the Effectiveness of Written Corrective Feedback in Second-Language Acquisition

ERIC Educational Resources Information Center

Wagner, Jason

2016-01-01

The purpose of this study is to provide a theoretical explanation for the effectiveness of Written Corrective Feedback (WCF) in increasing second-language (L2) students' grammatical accuracy. WCF is examined via Skill Acquisition Theory (SAT) in order to account for uneven patterns of its effectiveness. As the study demonstrates, WCF is effective…

Interparental Aggression and Antisocial Behavior among African American Youth: A Simultaneous Test of Competing Explanations

ERIC Educational Resources Information Center

Su, Xiaoli; Simons, Ronald L.; Simons, Leslie G.

2011-01-01

Interparental aggression has long been implicated as a cause of child and adolescent antisocial behavior. Four theoretical explanations (viz., an aggressogenic cognition model, general strain theory, an emotional security model, and a spillover model) have been proposed to account for this deleterious effect. To gain a better understanding of the…

The Physics of Flight: I. Fixed and Rotating Wings

ERIC Educational Resources Information Center

Linton, J. Oliver

2007-01-01

Almost all elementary textbook explanations of the theory of flight rely heavily on Bernoulli's principle and the fact that air travels faster over a wing than below it. In recent years the inadequacies and, indeed, fallacies in this explanation have been exposed (see Babinsky's excellent article in 2003 Phys. Educ. 38 497-503) and it is now…

Age and Ethnic Differences in Cold Weather and Contagion Theories of Colds and Flu

ERIC Educational Resources Information Center

Sigelman, Carol K.

2012-01-01

Age and ethnic group differences in cold weather and contagion or germ theories of infectious disease were explored in two studies. A cold weather theory was frequently invoked to explain colds and to a lesser extent flu but became less prominent with age as children gained command of a germ theory of disease. Explanations of how contact with…

Categorial Compositionality: A Category Theory Explanation for the Systematicity of Human Cognition

PubMed Central

Phillips, Steven; Wilson, William H.

2010-01-01

Classical and Connectionist theories of cognitive architecture seek to explain systematicity (i.e., the property of human cognition whereby cognitive capacity comes in groups of related behaviours) as a consequence of syntactically and functionally compositional representations, respectively. However, both theories depend on ad hoc assumptions to exclude specific instances of these forms of compositionality (e.g. grammars, networks) that do not account for systematicity. By analogy with the Ptolemaic (i.e. geocentric) theory of planetary motion, although either theory can be made to be consistent with the data, both nonetheless fail to fully explain it. Category theory, a branch of mathematics, provides an alternative explanation based on the formal concept of adjunction, which relates a pair of structure-preserving maps, called functors. A functor generalizes the notion of a map between representational states to include a map between state transformations (or processes). In a formal sense, systematicity is a necessary consequence of a higher-order theory of cognitive architecture, in contrast to the first-order theories derived from Classicism or Connectionism. Category theory offers a re-conceptualization for cognitive science, analogous to the one that Copernicus provided for astronomy, where representational states are no longer the center of the cognitive universe—replaced by the relationships between the maps that transform them. PMID:20661306

Categorial compositionality: a category theory explanation for the systematicity of human cognition.

PubMed

Phillips, Steven; Wilson, William H

2010-07-22

Classical and Connectionist theories of cognitive architecture seek to explain systematicity (i.e., the property of human cognition whereby cognitive capacity comes in groups of related behaviours) as a consequence of syntactically and functionally compositional representations, respectively. However, both theories depend on ad hoc assumptions to exclude specific instances of these forms of compositionality (e.g. grammars, networks) that do not account for systematicity. By analogy with the Ptolemaic (i.e. geocentric) theory of planetary motion, although either theory can be made to be consistent with the data, both nonetheless fail to fully explain it. Category theory, a branch of mathematics, provides an alternative explanation based on the formal concept of adjunction, which relates a pair of structure-preserving maps, called functors. A functor generalizes the notion of a map between representational states to include a map between state transformations (or processes). In a formal sense, systematicity is a necessary consequence of a higher-order theory of cognitive architecture, in contrast to the first-order theories derived from Classicism or Connectionism. Category theory offers a re-conceptualization for cognitive science, analogous to the one that Copernicus provided for astronomy, where representational states are no longer the center of the cognitive universe--replaced by the relationships between the maps that transform them.

System as metaphor in the psychology and biology of shame.

PubMed

Maunder, R

1996-01-01

Biological theories of brain and psychological theories of mind are two systems of explanation that seem related to one another. The nature of the relationship is problematic and constitutes the age-old mind-body problem. The most prominent solutions currently are variations of materialism. While psychological theories can be consistent with materialism, there remains a difficulty in comprehending nonphysical (social, psychological) causes of physical effects. This difficulty is an obstacle to integration in psychiatry, where we routinely assume that illnesses that include or depend on biological dysfunction are caused multifactorially by causal agents such as perceived parental warmth, parental loss, stressful life events, genetics, and personality (Hammen et al. 1992; Kendler et al. 1993). Unity theory adopts the stance that neurobiological theories and psychological theories are essentially disparate explanations of the same psychobiological events; thus the relationship of mind to brain is one of shared reference (Goodman 1991; Maunder 1995). In Goodman's model the gap between biological and psychological systems is not bridgeable. Different conceptual categories refer to the same referents but cannot interact with each other. Stepping into the breach, systems theory has been presented as offering a language that can bridge the gap between psychological and biological theories of causation (Schwartz 1981; Weiner 1989). Thus, there is a controversy about the applicability of systems theory for integration in psychiatry.

Plasma response to sustainment with imposed-dynamo current drive in HIT-SI and HIT-SI3

NASA Astrophysics Data System (ADS)

Hossack, A. C.; Jarboe, T. R.; Chandra, R. N.; Morgan, K. D.; Sutherland, D. A.; Penna, J. M.; Everson, C. J.; Nelson, B. A.

2017-07-01

The helicity injected torus—steady inductive (HIT-SI) program studies efficient, steady-state current drive for magnetic confinement plasmas using a novel experimental method. Stable, high-beta spheromaks have been sustained using steady, inductive current drive. Externally induced loop voltage and magnetic flux are oscillated together so that helicity and power injection are always positive, sustaining the edge plasma current indefinitely. Imposed-dynamo current drive (IDCD) theory further shows that the entire plasma current is sustained. The method is ideal for low aspect ratio, toroidal geometries with closed flux surfaces. Experimental studies of spheromak plasmas sustained with IDCD have shown stable magnetic profiles with evidence of pressure confinement. New measurements show coherent motion of a stable spheromak in response to the imposed perturbations. On the original device two helicity injectors were mounted on either side of the spheromak and the injected mode spectrum was predominantly n  =  1. Coherent, rigid motion indicates that the spheromak is stable and a lack of plasma-generated n  =  1 energy indicates that the maximum q is maintained below 1 during sustainment. Results from the HIT-SI3 device are also presented. Three inductive helicity injectors are mounted on one side of the spheromak flux conserver. Varying the relative injector phasing changes the injected mode spectrum which includes n  =  2, 3, and higher modes.

Theories of Occupational Segregation by Sex: An Overview.

ERIC Educational Resources Information Center

Anker, Richard

1997-01-01

Reviews theoretical explanations for gender segregation in occupations: neoclassical, human capital, institutional and labor market segmentation, and gender discrimination. Determines that gender discrimination theories are most compelling, given the enormous overlap in abilities and preferences of individual men and women. (SK)

Scientists Weight Facts, Theories on Aging

ERIC Educational Resources Information Center

Chemical and Engineering News, 1974

1974-01-01

Discusses some of the current theories on aging, such as biological time clocks for certain cells and on-off switches for genes, that were offered as explanations at the 140th annual meeting of the American Association for the Advancement of Science (JR)

The Behavioral and Social Sciences.

ERIC Educational Resources Information Center

Simon, Herbert A.

1980-01-01

This article reviews some recent technical progress in the social sciences and three frontier areas including evolutionary theory as related to sociobiology, the theory of human rational choice, and cognitive science. These areas offer explanations for broad areas of human behavior. (Author/SA)

Development of a Health Information Technology Acceptance Model Using Consumers’ Health Behavior Intention

PubMed Central

2012-01-01

Background For effective health promotion using health information technology (HIT), it is mandatory that health consumers have the behavioral intention to measure, store, and manage their own health data. Understanding health consumers’ intention and behavior is needed to develop and implement effective and efficient strategies. Objective To develop and verify the extended Technology Acceptance Model (TAM) in health care by describing health consumers’ behavioral intention of using HIT. Methods This study used a cross-sectional descriptive correlational design. We extended TAM by adding more antecedents and mediating variables to enhance the model’s explanatory power and to make it more applicable to health consumers’ behavioral intention. Additional antecedents and mediating variables were added to the hypothetical model, based on their theoretical relevance, from the Health Belief Model and theory of planned behavior, along with the TAM. We undertook structural equation analysis to examine the specific nature of the relationship involved in understanding consumers’ use of HIT. Study participants were 728 members recruited from three Internet health portals in Korea. Data were collected by a Web-based survey using a structured self-administered questionnaire. Results The overall fitness indices for the model developed in this study indicated an acceptable fit of the model. All path coefficients were statistically significant. This study showed that perceived threat, perceived usefulness, and perceived ease of use significantly affected health consumers’ attitude and behavioral intention. Health consumers’ health status, health belief and concerns, subjective norm, HIT characteristics, and HIT self-efficacy had a strong indirect impact on attitude and behavioral intention through the mediators of perceived threat, perceived usefulness, and perceived ease of use. Conclusions An extended TAM in the HIT arena was found to be valid to describe health consumers’ behavioral intention. We categorized the concepts in the extended TAM into 3 domains: health zone, information zone, and technology zone. PMID:23026508

Development of a health information technology acceptance model using consumers' health behavior intention.

PubMed

Kim, Jeongeun; Park, Hyeoun-Ae

2012-10-01

For effective health promotion using health information technology (HIT), it is mandatory that health consumers have the behavioral intention to measure, store, and manage their own health data. Understanding health consumers' intention and behavior is needed to develop and implement effective and efficient strategies. To develop and verify the extended Technology Acceptance Model (TAM) in health care by describing health consumers' behavioral intention of using HIT. This study used a cross-sectional descriptive correlational design. We extended TAM by adding more antecedents and mediating variables to enhance the model's explanatory power and to make it more applicable to health consumers' behavioral intention. Additional antecedents and mediating variables were added to the hypothetical model, based on their theoretical relevance, from the Health Belief Model and theory of planned behavior, along with the TAM. We undertook structural equation analysis to examine the specific nature of the relationship involved in understanding consumers' use of HIT. Study participants were 728 members recruited from three Internet health portals in Korea. Data were collected by a Web-based survey using a structured self-administered questionnaire. The overall fitness indices for the model developed in this study indicated an acceptable fit of the model. All path coefficients were statistically significant. This study showed that perceived threat, perceived usefulness, and perceived ease of use significantly affected health consumers' attitude and behavioral intention. Health consumers' health status, health belief and concerns, subjective norm, HIT characteristics, and HIT self-efficacy had a strong indirect impact on attitude and behavioral intention through the mediators of perceived threat, perceived usefulness, and perceived ease of use. An extended TAM in the HIT arena was found to be valid to describe health consumers' behavioral intention. We categorized the concepts in the extended TAM into 3 domains: health zone, information zone, and technology zone.

Constructor theory of life

PubMed Central

Marletto, Chiara

2015-01-01

Neo-Darwinian evolutionary theory explains how the appearance of purposive design in the adaptations of living organisms can have come about without their intentionally being designed. The explanation relies crucially on the possibility of certain physical processes: mainly, gene replication and natural selection. In this paper, I show that for those processes to be possible without the design of biological adaptations being encoded in the laws of physics, those laws must have certain other properties. The theory of what these properties are is not part of evolution theory proper, yet without it the neo-Darwinian theory does not fully achieve its purpose of explaining the appearance of design. To this end, I apply constructor theory's new mode of explanation to express exactly within physics the appearance of design, no-design laws, and the logic of self-reproduction and natural selection. I conclude that self-reproduction, replication and natural selection are possible under no-design laws, the only non-trivial condition being that they allow digital information to be physically instantiated. This has an exact characterization in the constructor theory of information. I also show that under no-design laws an accurate replicator requires the existence of a ‘vehicle’ constituting, together with the replicator, a self-reproducer. PMID:25589566

Monte Carlo calculation of the maximum therapeutic gain of tumor antivascular alpha therapy

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

Huang, Chen-Yu; Oborn, Bradley M.; Guatelli, Susanna

Purpose: Metastatic melanoma lesions experienced marked regression after systemic targeted alpha therapy in a phase 1 clinical trial. This unexpected response was ascribed to tumor antivascular alpha therapy (TAVAT), in which effective tumor regression is achieved by killing endothelial cells (ECs) in tumor capillaries and, thus, depriving cancer cells of nutrition and oxygen. The purpose of this paper is to quantitatively analyze the therapeutic efficacy and safety of TAVAT by building up the testing Monte Carlo microdosimetric models. Methods: Geant4 was adapted to simulate the spatial nonuniform distribution of the alpha emitter {sup 213}Bi. The intraluminal model was designed tomore » simulate the background dose to normal tissue capillary ECs from the nontargeted activity in the blood. The perivascular model calculates the EC dose from the activity bound to the perivascular cancer cells. The key parameters are the probability of an alpha particle traversing an EC nucleus, the energy deposition, the lineal energy transfer, and the specific energy. These results were then applied to interpret the clinical trial. Cell survival rate and therapeutic gain were determined. Results: The specific energy for an alpha particle hitting an EC nucleus in the intraluminal and perivascular models is 0.35 and 0.37 Gy, respectively. As the average probability of traversal in these models is 2.7% and 1.1%, the mean specific energy per decay drops to 1.0 cGy and 0.4 cGy, which demonstrates that the source distribution has a significant impact on the dose. Using the melanoma clinical trial activity of 25 mCi, the dose to tumor EC nucleus is found to be 3.2 Gy and to a normal capillary EC nucleus to be 1.8 cGy. These data give a maximum therapeutic gain of about 180 and validate the TAVAT concept. Conclusions: TAVAT can deliver a cytotoxic dose to tumor capillaries without being toxic to normal tissue capillaries.« less

A new formalism for modelling parameters α and β of the linear-quadratic model of cell survival for hadron therapy

NASA Astrophysics Data System (ADS)

Vassiliev, Oleg N.; Grosshans, David R.; Mohan, Radhe

2017-10-01

We propose a new formalism for calculating parameters α and β of the linear-quadratic model of cell survival. This formalism, primarily intended for calculating relative biological effectiveness (RBE) for treatment planning in hadron therapy, is based on a recently proposed microdosimetric revision of the single-target multi-hit model. The main advantage of our formalism is that it reliably produces α and β that have correct general properties with respect to their dependence on physical properties of the beam, including the asymptotic behavior for very low and high linear energy transfer (LET) beams. For example, in the case of monoenergetic beams, our formalism predicts that, as a function of LET, (a) α has a maximum and (b) the α/β ratio increases monotonically with increasing LET. No prior models reviewed in this study predict both properties (a) and (b) correctly, and therefore, these prior models are valid only within a limited LET range. We first present our formalism in a general form, for polyenergetic beams. A significant new result in this general case is that parameter β is represented as an average over the joint distribution of energies E 1 and E 2 of two particles in the beam. This result is consistent with the role of the quadratic term in the linear-quadratic model. It accounts for the two-track mechanism of cell kill, in which two particles, one after another, damage the same site in the cell nucleus. We then present simplified versions of the formalism, and discuss predicted properties of α and β. Finally, to demonstrate consistency of our formalism with experimental data, we apply it to fit two sets of experimental data: (1) α for heavy ions, covering a broad range of LETs, and (2) β for protons. In both cases, good agreement is achieved.

The Double-Anchoring Theory of Lightness Perception: A Comment on Bressan (2006)

ERIC Educational Resources Information Center

Howe, Piers D. L.; Sagreiya, Hersh; Curtis, Dwight L.; Zheng, Chengjie; Livingstone, Margaret S.

2007-01-01

Comments on an article by Bressan. Recently, a double-anchoring theory (DAT) of lightness perception was proposed (P. Bressan, 2006), which offers explanations for all the data explained by the original anchoring theory (A. Gilchrist et al., 1999), as well as a number of additional lightness phenomena. Consequently, DAT can account for an…

The Neuroscience of Self-Efficacy: Vertically Integrated Leisure Theory and Its Implications for Theory-Based Programming

ERIC Educational Resources Information Center

Stone, Garrett Anderson

2018-01-01

The purpose of this paper is to explain and establish a link between social-psychological and biological explanations of self-efficacy theory. Specifically, the paper uses a hypothetical rock climbing program to illustrate how a practitioner could enhance the four sources of self-efficacious beliefs (enactive attainment, vicarious experience,…

A Theoretical Analysis of Learning with Graphics--Implications for Computer Graphics Design.

ERIC Educational Resources Information Center

ChanLin, Lih-Juan

This paper reviews the literature pertinent to learning with graphics. The dual coding theory provides explanation about how graphics are stored and precessed in semantic memory. The level of processing theory suggests how graphics can be employed in learning to encourage deeper processing. In addition to dual coding theory and level of processing…

Prescription Drug Use among College Students: A Test of Criminal Spin Theory

ERIC Educational Resources Information Center

Lin, Wan-Chun

2017-01-01

Criminal spin theory developed by Ronel intends to provide a more comprehensive explanation of criminal behavior. It includes wide-ranging factors that impact human behavior at an individual, group, and cultural level. According to criminal spin theory, an event or a set of events can impact human emotions, thoughts, and behaviors. With the…

Naive Theory of Biology: The Pre-School Child's Explanation of Death

ERIC Educational Resources Information Center

Vlok, Milandre; de Witt, Marike W.

2012-01-01

This article explains the naive theory of biology that the pre-school child uses to explain the cause of death. The empirical investigation showed that the young participants do use a naive theory of biology to explain function and do make reference to "vitalistic causality" in explaining organ function. Furthermore, most of these…

Large-Scale Investigation of the Role of Trait Activation Theory for Understanding Assessment Center Convergent and Discriminant Validity

ERIC Educational Resources Information Center

Lievens, Filip; Chasteen, Christopher S.; Day, Eric Anthony; Christiansen, Neil D.

2006-01-01

This study used trait activation theory as a theoretical framework to conduct a large-scale test of the interactionist explanation of the convergent and discriminant validity findings obtained in assessment centers. Trait activation theory specifies the conditions in which cross-situationally consistent and inconsistent candidate performances are…

Carl Hempel's Philosophy of Science: How to Avoid Epistemic Discontinuity and Pedagogical Pitfalls

ERIC Educational Resources Information Center

Vemulapalli, G. Krishna; Byerly, Henry C.

2004-01-01

Mathematical theories are essential for explanations in physics, chemistry and engineering. These theories often incorporate functions that are defined by the irrelation to other variables in the theory but not with reference to experimental observations. The wave function in quantum mechanics is perhaps one of the best known example of such…

Schema Theories as a Base for the Structural Representation of the Knowledge State.

ERIC Educational Resources Information Center

Dochy, F. J. R. C.; Bouwens, M. R. J.

From the view of schema-transfer theory, the use of schemata with their several functions gives an explanation for the facilitative effect of prior knowledge on learning processes. This report gives a theoretical exploration of the concept of schemata, underlying schema theories, and functions of schemata to indicate the importance of schema…

Analysis of ovarian dose of women employed in the radium watch dial industry: A macrodosimetric and microdosimetric approach

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

Roeske, J.C.; Stinchcomb, T.G.; Schieve, L.

1999-01-01

In the 1920s, painters in the radium watch dial industry frequently tipped their brushes with their tongues resulting in the ingestion of radium-226 and/or radium-228. Earlier dosimetric studies (1950--1990) attempted to correlate the magnitude of biological effects (e.g., increased cancer incidence) with variations in radium uptake. Recently, there is a renewed interest on the part of epidemiologists studying additional possible effects (e.g., low birthrate and sex ratio). The goal of this work is to review and update the determination of dose to the ovaries from both external and internal radiation hazards in an attempt to correlate ovarian dose with thesemore » additional possible effects. The dose to the ovaries can be attributed to four major sources: (1) external gamma irradiation from the containers of radium paint; (2) alpha and (3) beta particle emissions due to sources which decay within the ovaries; and (4) internal gamma irradiation released throughout the body. Data obtained in earlier dosimetric studies on the quantity of Ra-226 and/or Ra-228 ingested were used in this study. Dose is estimated on a macroscopic scale by calculating the average dose deposited within the entire ovary. In addition, a microdosimetric analysis is performed which considers the statistical variation of energy deposited within individual oocyte nuclei. Sources of uncertainty, and the use of these data in new epidemiological studies are discussed.« less

Microdosimetric study for nanosecond pulsed electric fields on a cell circuit model with nucleus.

PubMed

Denzi, Agnese; Merla, Caterina; Camilleri, Paola; Paffi, Alessandra; d'Inzeo, Guglielmo; Apollonio, Francesca; Liberti, Micaela

2013-10-01

Recently, scientific interest in electric pulses, always more intense and shorter and able to induce biological effects on both plasma and nuclear membranes, has greatly increased. Hence, microdosimetric models that include internal organelles like the nucleus have assumed increasing importance. In this work, a circuit model of the cell including the nucleus is proposed, which accounts for the dielectric dispersion of all cell compartments. The setup of the dielectric model of the nucleus is of fundamental importance in determining the transmembrane potential (TMP) induced on the nuclear membrane; here, this is demonstrated by comparing results for three different sets of nuclear dielectric properties present in the literature. The results have been compared, even including or disregarding the dielectric dispersion of the nucleus. The main differences have been found when using pulses shorter than 10 ns. This is due to the fact that the high spectral components of the shortest pulses are differently taken into account by the nuclear membrane transfer functions computed with and without nuclear dielectric dispersion. The shortest pulses are also the most effective in porating the intracellular structures, as confirmed by the time courses of the TMP calculated across the plasma and nuclear membranes. We show how dispersive nucleus models are unavoidable when dealing with pulses shorter than 10 ns because of the large spectral contents arriving above 100 MHz, i.e., over the typical relaxation frequencies of the dipolar mechanism of the molecules constituting the nuclear membrane and the subcellular cell compartments.

Marxism, Liberalism, and Educational Theory.

ERIC Educational Resources Information Center

Margonis, Frank

1993-01-01

Examines educational theory, Marxism, and liberalism, discussing Kenneth Strike's "Liberal Justice and the Marxist Critique of Education" and Daniel Liston's "Capitalist Schools: Explanation and Ethics in Radical Studies of Schooling." Suggests that both authors are too hasty in abandoning Marxism and that Marxism is the…

Ultrasonic cleaning: Fundamental theory and application

NASA Technical Reports Server (NTRS)

Fuchs, F. John

1995-01-01

This presentation describes: the theory of ultrasonics, cavitation and implosion; the importance and application of ultrasonics in precision cleaning; explanations of ultrasonic cleaning equipment options and their application; process parameters for ultrasonic cleaning; and proper operation of ultrasonic cleaning equipment to achieve maximum results.

Cultural Explanations for Racial and Ethnic Stratification in Academic Achievement: A Call for a New and Improved Theory

ERIC Educational Resources Information Center

Warikoo, Natasha; Carter, Prudence

2009-01-01

In this article we assess the literature on cultural explanations for ethno-racial differences in K-12 schooling and academic performance. Some cultural arguments problematically define certain ethno-racial identities and cultures as subtractive from the goal of academic mobility while defining the ethnic cultures and identities of others as…

Too Much Control Can Hurt: A Threaded Cognition Model of the Attentional Blink

ERIC Educational Resources Information Center

Taatgen, Niels A.; Juvina, Ion; Schipper, Marc; Borst, Jelmer P.; Martens, Sander

2009-01-01

Explanations for the attentional blink (AB; a deficit in identifying the second of two targets when presented 200-500ms after the first) have recently shifted from limitations in memory consolidation to disruptions in cognitive control. With a new model based on the threaded cognition theory of multi-tasking we propose a different explanation: the…

Prevalence, pathophysiological mechanisms and factors affecting urolithiasis.

PubMed

Khan, Aslam

2018-05-01

The formation of urinary stone, urolithiasis, is one the oldest known disease affecting human throughout different civilizations and times. The exact pathophysiological mechanism of urolithiasis is not yet clear, as these calculi are of various types and too complex for simple understanding. A single theory cannot explain its formation; therefore, different theories are presented in various times for its explanation like free particle, fixed particle, Randall's plaque theory. In addition, various factors and components are identified that play an important role in the formation of these urinary calculi. In this review, composition of kidney stones, its prevalence/incidence, explanation of pathophysiological mechanisms and role of various factors; urinary pH, uric acid, parathyroid hormone, citrate, oxalate, calcium and macromolecules; osteopontin, matrix Gla protein, kidney injury molecules, urinary prothrombin fragment-1, Tamm-Horsfall protein, inter-α-inhibitors, have been discussed in detail.

Music-colour synaesthesia: Concept, context and qualia.

PubMed

Curwen, Caroline

2018-05-01

This review provides a commentary on coloured-hearing arising on hearing music: music-colour synaesthesia. Although traditionally explained by the hyperconnectivity theory (Ramachandran & Hubbard, 2001a) and the disinhibited feedback theory (Grossenbacher & Lovelace, 2001) as a purely perceptual phenomenon, the review of eight coloured-hearing neuroimaging studies shows that it may not be assumed that these explanations are directly translatable to music-colour synaesthesia. The concept of 'ideaesthesia' (Nikolić, 2009) and the role of conceptual and semantic inducers challenge the likelihood of a single mechanism underlying the cause of synaesthesia and argue for a move away from a purely sensory to sensory explanation. Finally, music-colour synaesthesia forms a challenge for established philosophical theories and the position of synaesthesia is considered within the larger context of musical qualia. Copyright © 2018 Elsevier Inc. All rights reserved.

Social network extraction based on Web: 3. the integrated superficial method

NASA Astrophysics Data System (ADS)

Nasution, M. K. M.; Sitompul, O. S.; Noah, S. A.

2018-03-01

The Web as a source of information has become part of the social behavior information. Although, by involving only the limitation of information disclosed by search engines in the form of: hit counts, snippets, and URL addresses of web pages, the integrated extraction method produces a social network not only trusted but enriched. Unintegrated extraction methods may produce social networks without explanation, resulting in poor supplemental information, or resulting in a social network of durmise laden, consequently unrepresentative social structures. The integrated superficial method in addition to generating the core social network, also generates an expanded network so as to reach the scope of relation clues, or number of edges computationally almost similar to n(n - 1)/2 for n social actors.

Women Administrators as Instructional Leaders

ERIC Educational Resources Information Center

Horner, Beth A.

2013-01-01

Women are under-represented in educational research and are much less likely to hold administrative positions than are men. This study, using the Liberal Feminist Theory and Structural Barrier Theory, proffers possible explanations for this phenomenon. Four women leaders were interviewed to gain insight into their instructional leadership…

A Response to Jordan's (2004) "Explanatory Adequacy and Theories of Second Language Acquisition"

ERIC Educational Resources Information Center

Gregg, Kevin R.

2005-01-01

In a recent paper (Jordan, Geoff Jordan takes issue with some of my claims about second language acquisition (SLA) theory. Specifically, he queries the necessity of a property theory, and he finds my discussion of explanation unsatisfactory. In this brief reply, I try to answer his criticisms. In a brief but interesting paper, Geoff Jordan (2004:…

The Utility of Vulnerability and Social Capital Theories in Studying the Impact of Hurricane Katrina on the Elderly

ERIC Educational Resources Information Center

Durant, Thomas J., Jr.

2011-01-01

The definition of a disaster is followed by an explanation of vulnerability and social capital theories. The importance of using a sound theoretical framework and the utility and efficacy of vulnerability and social capital theories in studying the impact of natural disasters on the elderly population are emphasized and discussed. The conclusion…

Teaching for Hot Conceptual Change: Towards a New Model, beyond the Cold and Warm Ones

ERIC Educational Resources Information Center

Kural, Mehmet; Kocakülah, M. Sabri

2016-01-01

At the beginning of the 1980s, one of the most striking explanations of conceptual change was made by Posner, Strike, Hewson & Gertzog (1982) with a Conceptual Change Theory based on a Scientific Revolution Theory of Kuhn (1970). In Conceptual Change Theory, learning was explained with the Piaget (1970)'s concepts such as assimilation and…

Schema Theory Compared to Text-centered Theory as an Explanation for the Reader's Understanding of a Business Message.

ERIC Educational Resources Information Center

Faris, Kay A.; Smeltzer, Larry R.

1997-01-01

Examines variables affecting reader understanding of business writing. Notes that 57 business students and 82 non-business students read either a coherent or a non-coherent version of the same text and then took a test measuring their comprehension. Finds that background knowledge (schema theory) affected a reader's ability to understand business…

Physics of risk and uncertainty in quantum decision making

NASA Astrophysics Data System (ADS)

Yukalov, V. I.; Sornette, D.

2009-10-01

The Quantum Decision Theory, developed recently by the authors, is applied to clarify the role of risk and uncertainty in decision making and in particular in relation to the phenomenon of dynamic inconsistency. By formulating this notion in precise mathematical terms, we distinguish three types of inconsistency: time inconsistency, planning paradox, and inconsistency occurring in some discounting effects. While time inconsistency is well accounted for in classical decision theory, the planning paradox is in contradiction with classical utility theory. It finds a natural explanation in the frame of the Quantum Decision Theory. Different types of discounting effects are analyzed and shown to enjoy a straightforward explanation within the suggested theory. We also introduce a general methodology based on self-similar approximation theory for deriving the evolution equations for the probabilities of future prospects. This provides a novel classification of possible discount factors, which include the previously known cases (exponential or hyperbolic discounting), but also predicts a novel class of discount factors that decay to a strictly positive constant for very large future time horizons. This class may be useful to deal with very long-term discounting situations associated with intergenerational public policy choices, encompassing issues such as global warming and nuclear waste disposal.

General-purpose abductive algorithm for interpretation

NASA Astrophysics Data System (ADS)

Fox, Richard K.; Hartigan, Julie

1996-11-01

Abduction, inference to the best explanation, is an information-processing task that is useful for solving interpretation problems such as diagnosis, medical test analysis, legal reasoning, theory evaluation, and perception. The task is a generative one in which an explanation comprising of domain hypotheses is assembled and used to account for given findings. The explanation is taken to be an interpretation as to why the findings have arisen within the given situation. Research in abduction has led to the development of a general-purpose computational strategy which has been demonstrated on all of the above types of problems. This abduction strategy can be performed in layers so that different types of knowledge can come together in deriving an explanation at different levels of description. Further, the abduction strategy is tractable and offers a very useful tradeoff between confidence in the explanation and completeness of the explanation. This paper will describe this computational strategy for abduction and demonstrate its usefulness towards perceptual problems by examining problem-solving systems in speech recognition and natural language understanding.

A history of gravity: An introduction to the epistemology of Paul Feyerabend

NASA Astrophysics Data System (ADS)

Rodrigues, Danilo Miranda

2015-08-01

The goal of this work is to show an historical introduction to epistemology of Paul Feyerabend and the importance of his concept of epistemological anarchism for education.Feyerabend defended that different and even contradictory theories must be used in education, this multiplicity of possible explanations for natural phenomena is important to express the real development of science.There are many different explanations for the fall of bodies, since the "natural places" in Aristotle until the Newtonian Gravitation or the General Relativity. The contact with many different explanations has as important contribution for the learning of Astronomy.

Explanation and the Theory of Expert Problem Solving

DTIC Science & Technology

1990-02-01

specified output, Our work has aimed to identify the individual generic tasks, to analyze them properly, and to clarify their relationships to more...coverage of hypotheses must be tractable. that there cannot be many incompatibility relationships or cancellation effects between individual hypotheses. and...no necessary relationship between this justificatory argument and the actual reasoning that produced the solution. In Wick’s system the explanation

Job-Related Training and Benefits for Individuals: A Review of Evidence and Explanations. OECD Education Working Papers, No. 19

ERIC Educational Resources Information Center

Hansson, Bo

2008-01-01

This paper reviews the literature on job-related training and the effects of these investments for different groups of individuals. The paper also elaborates on the theories, empirical explanations, and policy implications that can be drawn from these findings. Employer-provided training is by far the most important source of further education and…

A microgenetic study of learning about the molecular theory of matter and chemical reactions

NASA Astrophysics Data System (ADS)

Chinn, Clark Allen

This paper reports the results of an experimental microgenetic study of children learning complex knowledge from text and experiments. The study had two goals. The first was to investigate fine-grained, moment-to-moment changes in knowledge as middle-school students learned about molecules and chemical reactions over thirteen sessions. The second was to investigate the effects of two instructional treatments, one using implicit textbook explanations and one using explicit explanations developed according to a theory of how scientific knowledge is structured. In the study, 61 sixth- and seventh-graders worked one on one with undergraduate instructors in eleven sessions of about 50 to 80 minutes. The instructors guided the students in conducting experiments and thinking out loud about texts. Topics studied included molecules, states of matter, chemical reactions, and heat transfer. A dense array of questions provided a detailed picture of children's moment-to-moment and day-to-day changes in knowledge. Three results chapters address students' preinstructional knowledge, the effects of the experimental treatment at posttest, and five detailed case studies of students' step-by-step knowledge change over eleven sessions. The chapter on preinstructional knowledge discussed three aspects of global knowledge change: conceptual change, coherence, and entrenchment. Notably, this chapter provides systematic evidence that children's knowledge was fragmented and that consistency with general unifying principles did not guarantee a highly coherent body of knowledge. The experimental manipulation revealed a strong advantage for explicit explanations over implicit textbook explanations. Multiple explicit explanations (e.g., highly explicit explanations of three or four chemical reactions) appeared to be necessary for students to master key concepts. Microgenetic analyses of five cases addressed eight empirical issues that should be addressed by any theory of knowledge acquisition: (a) the nature of the overall knowledge change, (b) the progression of intermediate states during knowledge change, (c) initiators of knowledge change, (d) interactions of prior background knowledge and prior domain knowledge during knowledge changes, (e) the fate of old and new knowledge, (f) the relationship between belief and knowledge, (g) changes in meta-awareness, and (h) factors that influenced the course of knowledge change.

[Features of PHITS and its application to medical physics].

PubMed

Hashimoto, Shintaro; Niita, Koji; Matsuda, Norihiro; Iwamoto, Yosuke; Iwase, Hiroshi; Sato, Tatsuhiko; Noda, Shusaku; Ogawa, Tatsuhiko; Nakashima, Hiroshi; Fukahori, Tokio; Furuta, Takuya; Chiba, Satoshi

2013-01-01

PHITS is a general purpose Monte Carlo particle transport simulation code to analyze the transport in three-dimensional phase space and collisions of nearly all particles, including heavy ions, over wide energy range up to 100 GeV/u. Various quantities, such as particle fluence and deposition energies in materials, can be deduced using estimator functions "tally". Recently, a microdosimetric tally function was also developed to apply PHITS to medical physics. Owing to these features, PHITS has been used for medical applications, such as radiation therapy and protection.

Lay Americans' views of why scientists disagree with each other.

PubMed

Johnson, Branden B; Dieckmann, Nathan F

2017-10-01

A survey experiment assessed response to five explanations of scientific disputes: problem complexity, self-interest, values, competence, and process choices (e.g. theories and methods). A US lay sample ( n = 453) did not distinguish interests from values, nor competence from process, as explanations of disputes. Process/competence was rated most likely and interests/values least; all, on average, were deemed likely to explain scientific disputes. Latent class analysis revealed distinct subgroups varying in their explanation preferences, with a more complex latent class structure for participants who had heard of scientific disputes in the past. Scientific positivism and judgments of science's credibility were the strongest predictors of latent class membership, controlling for scientific reasoning, political ideology, confidence in choice, scenario, education, gender, age, and ethnicity. The lack of distinction observed overall between different explanations, as well as within classes, raises challenges for further research on explanations of scientific disputes people find credible and why.

Explanation and Prediction: Building a Unified Theory of Librarianship, Concept and Review.

ERIC Educational Resources Information Center

McGrath, William E.

2002-01-01

Develops a comprehensive, unified, explanatory theory of librarianship by first making an analogy to the unification of the fundamental forces of nature. Topics include dependent and independent variables; publishing; acquisitions; classification and organization of knowledge; storage, preservation, and collection management; collections; and…

Motor Skill Learning in Children.

ERIC Educational Resources Information Center

Gabbard, Carl P.

The purpose of this article is to briefly describe schema theory and indicate its relevance to early childhood development, with specific reference to children's acquisition of motor skills. Schema theory proposes an explanation of how individuals learn and perform a seemingly endless variety of movements. According to Schmidt (1975), goal…

Introduction to Educational Leadership and Organizational Behavior: Theory into Practice. Second Edition

ERIC Educational Resources Information Center

Chance, Patti L.

2009-01-01

Like the bestselling first edition, this introductory textbook succinctly presents concepts and theories of educational leadership and organizational behavior and immediately applies them to problems of practice. It includes practical case studies, real-world scenarios and analyses, reflection questions, and straightforward explanations of…

Psychologic theories in functional neurologic disorders.

PubMed

Carson, A; Ludwig, L; Welch, K

2016-01-01

In this chapter we review key psychologic theories that have been mooted as possible explanations for the etiology of functional neurologic symptoms, conversion disorder, and hysteria. We cover Freudian psychoanalysis and later object relations and attachment theories, social theories, illness behavior, classic and operant conditioning, social learning theory, self-regulation theory, cognitive-behavioral theories, and mindfulness. Dissociation and modern cognitive neuroscience theories are covered in other chapters in this series and, although of central importance, are omitted from this chapter. Our aim is an overview with the emphasis on breadth of coverage rather than depth. © 2016 Elsevier B.V. All rights reserved.

Widespread correlations between dominance and homozygous effects of mutations: implications for theories of dominance.

PubMed

Phadnis, Nitin; Fry, James D

2005-09-01

The dominance of deleterious mutations has important consequences for phenomena such as inbreeding depression, the evolution of diploidy, and levels of natural genetic variation. Kacser and Burns' metabolic theory provides a paradigmatic explanation for why most large-effect mutations are recessive. According to the metabolic theory, the recessivity of large-effect mutations is a consequence of a diminishing-returns relationship between flux through a metabolic pathway and enzymatic activity at any step in the pathway, which in turn is an inevitable consequence of long metabolic pathways. A major line of support for this theory was the demonstration of a negative correlation between homozygous effects and dominance of mutations in Drosophila, consistent with a central prediction of the metabolic theory. Using data on gene deletions in yeast, we show that a negative correlation between homozygous effects and dominance of mutations exists for all major categories of genes analyzed, not just those encoding enzymes. The relationship between dominance and homozygous effects is similar for duplicated and single-copy genes and for genes whose products are members of protein complexes and those that are not. A complete explanation of dominance therefore requires either a generalization of Kacser and Burns' theory to nonenzyme genes or a new theory.

Modular structure of functional networks in olfactory memory.

PubMed

Meunier, David; Fonlupt, Pierre; Saive, Anne-Lise; Plailly, Jane; Ravel, Nadine; Royet, Jean-Pierre

2014-07-15

Graph theory enables the study of systems by describing those systems as a set of nodes and edges. Graph theory has been widely applied to characterize the overall structure of data sets in the social, technological, and biological sciences, including neuroscience. Modular structure decomposition enables the definition of sub-networks whose components are gathered in the same module and work together closely, while working weakly with components from other modules. This processing is of interest for studying memory, a cognitive process that is widely distributed. We propose a new method to identify modular structure in task-related functional magnetic resonance imaging (fMRI) networks. The modular structure was obtained directly from correlation coefficients and thus retained information about both signs and weights. The method was applied to functional data acquired during a yes-no odor recognition memory task performed by young and elderly adults. Four response categories were explored: correct (Hit) and incorrect (False alarm, FA) recognition and correct and incorrect rejection. We extracted time series data for 36 areas as a function of response categories and age groups and calculated condition-based weighted correlation matrices. Overall, condition-based modular partitions were more homogeneous in young than elderly subjects. Using partition similarity-based statistics and a posteriori statistical analyses, we demonstrated that several areas, including the hippocampus, caudate nucleus, and anterior cingulate gyrus, belonged to the same module more frequently during Hit than during all other conditions. Modularity values were negatively correlated with memory scores in the Hit condition and positively correlated with bias scores (liberal/conservative attitude) in the Hit and FA conditions. We further demonstrated that the proportion of positive and negative links between areas of different modules (i.e., the proportion of correlated and anti-correlated areas) accounted for most of the observed differences in signed modularity. Taken together, our results provided some evidence that the neural networks involved in odor recognition memory are organized into modules and that these modular partitions are linked to behavioral performance and individual strategies. Copyright © 2014 Elsevier Inc. All rights reserved.

Do Workers Who Experience Conflict between the Work and Family Domains Hit a "Glass Ceiling?": A Meta-Analytic Examination

ERIC Educational Resources Information Center

Hoobler, Jenny M.; Hu, Jia; Wilson, Morgan

2010-01-01

Based in Conservation of Resources (COR; Hobfoll, 1989) and self-verification (Swann, 1987) theories, we argue that when workers experience conflict between the work and family domains, this should have implications for evaluations of their work performance and ultimately affect more "objective" career outcomes such as salary and hierarchical…

The Nature of Self-Regulatory Fatigue and "Ego Depletion": Lessons From Physical Fatigue.

PubMed

Evans, Daniel R; Boggero, Ian A; Segerstrom, Suzanne C

2015-07-30

Self-regulation requires overriding a dominant response and leads to temporary self-regulatory fatigue. Existing theories of the nature and causes of self-regulatory fatigue highlight physiological substrates such as glucose, or psychological processes such as motivation, but these explanations are incomplete on their own. Historically, theories of physical fatigue demonstrate a similar pattern of useful but incomplete explanations, as recent views of physical fatigue emphasize the roles of both physiological and psychological factors. In addition to accounting for multiple inputs, these newer views also explain how fatigue can occur even in the presence of sufficient resources. Examining these newer theories of physical fatigue can serve as a foundation on which to build a more comprehensive understanding of self-regulatory fatigue that integrates possible neurobiological underpinnings of physical and self-regulatory fatigue, and suggests the possible function of self-regulatory fatigue. © 2015 by the Society for Personality and Social Psychology, Inc.

Evolutionary contributions to the study of human fertility.

PubMed

Sear, Rebecca

2015-01-01

Demography, lacking an overarching theoretical framework of its own, has drawn on theories in many other social sciences to inform its analyses. The aim of this paper is to bring to the demographic community's attention research in the evolutionary sciences on fertility, and to demonstrate that evolutionary theory can be another useful tool in the demographer's toolkit. I first dispel some myths which impede the incorporation of evolutionary theory into demography: I make it clear that evolutionary explanations do not assume that all human behaviour is hardwired and functions to maximize genetic fitness; that they are able to explain variation in human behaviour; and that they are not necessarily alternatives to social science explanations. I then describe the diversity of work on fertility by evolutionary researchers, particularly human evolutionary ecologists and cultural evolutionists, and illustrate the usefulness of the evolutionary approach with examples of its application to age at first birth and the fertility transition.

Intention Seekers: Conspiracist Ideation and Biased Attributions of Intentionality

PubMed Central

2015-01-01

Conspiracist beliefs are widespread and potentially hazardous. A growing body of research suggests that cognitive biases may play a role in endorsement of conspiracy theories. The current research examines the novel hypothesis that individuals who are biased towards inferring intentional explanations for ambiguous actions are more likely to endorse conspiracy theories, which portray events as the exclusive product of intentional agency. Study 1 replicated a previously observed relationship between conspiracist ideation and individual differences in anthropomorphisation. Studies 2 and 3 report a relationship between conspiracism and inferences of intentionality for imagined ambiguous events. Additionally, Study 3 again found conspiracist ideation to be predicted by individual differences in anthropomorphism. Contrary to expectations, however, the relationship was not mediated by the intentionality bias. The findings are discussed in terms of a domain-general intentionality bias making conspiracy theories appear particularly plausible. Alternative explanations are suggested for the association between conspiracism and anthropomorphism. PMID:25970175

The nature of self-regulatory fatigue and “ego depletion”: Lessons from physical fatigue

PubMed Central

Evans, Daniel R.; Boggero, Ian A.; Segerstrom, Suzanne C.

2016-01-01

Self-regulation requires overriding a dominant response, and leads to temporary self-regulatory fatigue. Existing theories of the nature and causes of self-regulatory fatigue highlight physiological substrates such as glucose or psychological processes such as motivation, but these explanations are incomplete on their own. Historically, theories of physical fatigue demonstrate a similar pattern of useful but incomplete explanations, as recent views of physical fatigue emphasize the roles of both physiological and psychological factors. In addition to accounting for multiple inputs, these newer views also explain how fatigue can occur even in the presence of sufficient resources. Examining these newer theories of physical fatigue can serve as a foundation on which to build a more comprehensive understanding of self-regulatory fatigue that integrates possible neurobiological underpinnings of physical and self-regulatory fatigue, and suggests the possible function of self-regulatory fatigue. PMID:26228914

Contingency Management and Deliberative Decision-Making Processes.

PubMed

Regier, Paul S; Redish, A David

2015-01-01

Contingency management is an effective treatment for drug addiction. The current explanation for its success is rooted in alternative reinforcement theory. We suggest that alternative reinforcement theory is inadequate to explain the success of contingency management and produce a model based on demand curves that show how little the monetary rewards offered in this treatment would affect drug use. Instead, we offer an explanation of its success based on the concept that it accesses deliberative decision-making processes. We suggest that contingency management is effective because it offers a concrete and immediate alternative to using drugs, which engages deliberative processes, improves the ability of those deliberative processes to attend to non-drug options, and offsets more automatic action-selection systems. This theory makes explicit predictions that can be tested, suggests which users will be most helped by contingency management, and suggests improvements in its implementation.

Contingency Management and Deliberative Decision-Making Processes

PubMed Central

Regier, Paul S.; Redish, A. David

2015-01-01

Contingency management is an effective treatment for drug addiction. The current explanation for its success is rooted in alternative reinforcement theory. We suggest that alternative reinforcement theory is inadequate to explain the success of contingency management and produce a model based on demand curves that show how little the monetary rewards offered in this treatment would affect drug use. Instead, we offer an explanation of its success based on the concept that it accesses deliberative decision-making processes. We suggest that contingency management is effective because it offers a concrete and immediate alternative to using drugs, which engages deliberative processes, improves the ability of those deliberative processes to attend to non-drug options, and offsets more automatic action-selection systems. This theory makes explicit predictions that can be tested, suggests which users will be most helped by contingency management, and suggests improvements in its implementation. PMID:26082725

Causality from the Cosmological Perspective in Vedanta and Western Physics.

NASA Astrophysics Data System (ADS)

Hawley, Danny Lee

The relation between Western physics and Indian Vedanta philosophy is investigated through the topic of causality, taken in the sense of explanatory theories of the origin of the universe and the relations among its physical, mental, and spiritual aspects. Both physics and Vedanta have a common goal of explanation by means of a unitary principle. While physics has long been separated from metaphysics, its discoveries indicate that consciousness must be included in a complete explanation. Consciousness is taken as the fundamental basis and source of all phenomena in Vedanta. This work traces the developments of causal explanation in Western physics and Indian philosophy, and considers how these views may relate to each other and how they may together suggest a comprehensive view of reality. Approaches typically applied by historians of religion to the study of creation myths, especially the psychological approach which considers myths from the perspective or cyclical stages of conscious development, are applied to the causal theories of the two cultures. The question of how causal explanations attempt to bridge the gap between cause and effect, unity and multiplicity, absolute and relative, conscious and unconscious, etc., is addressed. Though the investigation begins from the earliest causal explanations, viz., creation myths, emphasis is placed upon Samkara's commentaries of Advaita Vedanta, examined in the original Sanskrit, and upon the convergence of modern field theory, astrophysics, and cosmology, seen from the perspective of a previous doctorate in physics. Consideration is given to the comparison between physics and Vedanta as to goals, methods, and domains, to the question of the incompleteness of physics and the extent to which it nevertheless points beyond itself, to the possibility of a synthetic view and how it might be effected, and to analogies and metaphors through which physics and Vedanta may illuminate each other. An intuitive picture is presented which uses an analogy between higher dimensions and levels of consciousness to suggest a comprehensive view.

Visual versus Phonological Abilities in Spanish Dyslexic Boys and Girls

ERIC Educational Resources Information Center

Bednarek, Dorota; Saldana, David; Garcia, Isabel

2009-01-01

Phonological and visual theories propose different primary deficits as part of the explanation for dyslexia. Both theories were put to test in a sample of Spanish dyslexic readers. Twenty-one dyslexic and 22 typically-developing children matched on chronological age were administered phonological discrimination and awareness tasks and coherent…

How Children Learn Mathematics, Teaching Implications of Piaget's Research.

ERIC Educational Resources Information Center

Copeland, Richard W.

Included are the standard topics presented in the undergraduate and/or graduate course on methods of teaching mathematics in elementary education. Chapter 1 describes the historical development of learning theories, including Piaget's. Chapter 2 contains a biographical sketch of Piaget and an explanation of his theory of cognitive development.…

Hemispheric Dissociation and Dyslexia in a Computational Model of Reading

ERIC Educational Resources Information Center

Monaghan, Padraic; Shillcock, Richard

2008-01-01

There are several causal explanations for dyslexia, drawing on distinctions between dyslexics and control groups at genetic, biological, or cognitive levels of description. However, few theories explicitly bridge these different levels of description. In this paper, we review a long-standing theory that some dyslexics' reading impairments are due…

Facilitating Representation Change in Insight Problems through Training

ERIC Educational Resources Information Center

Patrick, John; Ahmed, Afia

2014-01-01

Our aim in this article is to elaborate the role of training in representational change theory (RCT), particularly in terms of Ohlsson's (2011) spread of activation explanation (named "redistribution theory"), and to develop novel training manipulations that effect the re-encoding mechanism proposed by RCT (Ohlsson, 1992). Two…

An Attitudinal Explanation of Biases in the Criminal Justice System: An Empirical Testing of Defensive Attribution Theory

ERIC Educational Resources Information Center

Herzog, Sergio

2008-01-01

Theoretical perspectives, supported by empirical evidence, have consistently argued that the judicial treatment of offenders by criminal justice agents is sometimes biased by extralegal factors, such as offenders' sociodemographic characteristics. According to defensive attribution theory, individuals tend to protect themselves against unfortunate…

Beyond Bifurcation: Examining the Conventions of Organic Agriculture in New Zealand

ERIC Educational Resources Information Center

Rosin, Christopher; Campbell, Hugh

2009-01-01

The last 10 years have witnessed numerous attempts to evaluate the merits of new theoretical approaches--ranging from Actor Network Theory to "post-structural" Political Economy and inhabiting a "post-Political Economy' theoretical space--to the explanation of global agricultural change. This article examines Convention Theory (CT)…

Intuitive Expertise: Theories and Empirical Evidence

ERIC Educational Resources Information Center

Harteis, Christian; Billett, Stephen

2013-01-01

Intuition has been long seen as an element of effective human performance in demanding tasks (i.e. expertise). But its form, constitutive elements and development remain subject to diverse explanations. This paper discusses these elements and explores theories and empirical evidence about what constitutes intuitive expertise, and offers an account…

Getting a Puff: A Social Learning Test of Adolescents Smoking

ERIC Educational Resources Information Center

Monroe, Jacquelyn

2004-01-01

This article is a description of a study that sought to examine the applicability of Ronald Akers' social learning theory. According to Akers' theory, differential associations with smokers, differential reinforcements for smoking, favorable definitions of smoking and the availability of role models (imitation) offer an explanation as to why…

A Phenomenological Study on Lack of Motivation

ERIC Educational Resources Information Center

Educational Research and Reviews, 2013

2013-01-01

The aim of this research is to point out the underlying reasons about the lack of motivation at academic activities concerning Attribution Theory. Attribution Theory trys to understand how the people answer "why" question and how they do casual explanations. This research is a qualitative based research. It used the phenomenological…

The Evolution of Human Longevity: Toward a Biocultural Theory.

ERIC Educational Resources Information Center

Mayer, Peter J.

Homo sapiens is the only extant species for which there exists a significant post-reproductive period in the normal lifespan. Explanations for the evolution of this species-specific trait are possible through "non-deterministic" theories of aging positing "wear and tear" or the failure of nature to eliminate imperfection, or…

Practical Applications of the Research on Epistemological Beliefs

ERIC Educational Resources Information Center

Nist, Sherrie L.; Holschuh, Jodi Patrick

2005-01-01

Theories of epistemological beliefs focus on individuals' perceptions about what knowledge is and where knowledge comes from. These beliefs are part of, and may in fact direct, the cognitive processes involved in learning. Research stemming from these theories offers varied explanations as to how beliefs relate to student learning and academic…

Biased ligand quantification in drug discovery: from theory to high throughput screening to identify new biased μ opioid receptor agonists

PubMed Central

Winpenny, David; Clark, Mellissa

2016-01-01

Background and Purpose Biased GPCR ligands are able to engage with their target receptor in a manner that preferentially activates distinct downstream signalling and offers potential for next generation therapeutics. However, accurate quantification of ligand bias in vitro is complex, and current best practice is not amenable for testing large numbers of compound. We have therefore sought to apply ligand bias theory to an industrial scale screening campaign for the identification of new biased μ receptor agonists. Experimental Approach μ receptor assays with appropriate dynamic range were developed for both Gαi‐dependent signalling and β‐arrestin2 recruitment. Δlog(Emax/EC50) analysis was validated as an alternative for the operational model of agonism in calculating pathway bias towards Gαi‐dependent signalling. The analysis was applied to a high throughput screen to characterize the prevalence and nature of pathway bias among a diverse set of compounds with μ receptor agonist activity. Key Results A high throughput screening campaign yielded 440 hits with greater than 10‐fold bias relative to DAMGO. To validate these results, we quantified pathway bias of a subset of hits using the operational model of agonism. The high degree of correlation across these biased hits confirmed that Δlog(Emax/EC50) was a suitable method for identifying genuine biased ligands within a large collection of diverse compounds. Conclusions and Implications This work demonstrates that using Δlog(Emax/EC50), drug discovery can apply the concept of biased ligand quantification on a large scale and accelerate the deliberate discovery of novel therapeutics acting via this complex pharmacology. PMID:26791140

Incidental Memory Encoding Assessed with Signal Detection Theory and Functional Magnetic Resonance Imaging (fMRI).

PubMed

Clemens, Benjamin; Regenbogen, Christina; Koch, Kathrin; Backes, Volker; Romanczuk-Seiferth, Nina; Pauly, Katharina; Shah, N Jon; Schneider, Frank; Habel, Ute; Kellermann, Thilo

2015-01-01

In functional magnetic resonance imaging (fMRI) studies that apply a "subsequent memory" approach, successful encoding is indicated by increased fMRI activity during the encoding phase for hits vs. misses, in areas underlying memory encoding such as the hippocampal formation. Signal-detection theory (SDT) can be used to analyze memory-related fMRI activity as a function of the participant's memory trace strength (d(')). The goal of the present study was to use SDT to examine the relationship between fMRI activity during incidental encoding and participants' recognition performance. To implement a new approach, post-experimental group assignment into High- or Low Performers (HP or LP) was based on 29 healthy participants' recognition performance, assessed with SDT. The analyses focused on the interaction between the factors group (HP vs. LP) and recognition performance (hits vs. misses). A whole-brain analysis revealed increased activation for HP vs. LP during incidental encoding for remembered vs. forgotten items (hits > misses) in the insula/temporo-parietal junction (TPJ) and the fusiform gyrus (FFG). Parameter estimates in these regions exhibited a significant positive correlation with d('). As these brain regions are highly relevant for salience detection (insula), stimulus-driven attention (TPJ), and content-specific processing of mnemonic stimuli (FFG), we suggest that HPs' elevated memory performance was associated with enhanced attentional and content-specific sensory processing during the encoding phase. We provide first correlative evidence that encoding-related activity in content-specific sensory areas and content-independent attention and salience detection areas influences memory performance in a task with incidental encoding of facial stimuli. Based on our findings, we discuss whether the aforementioned group differences in brain activity during incidental encoding might constitute the basis of general differences in memory performance between HP and LP.

Laser Cooling of Neutral Atoms.

DTIC Science & Technology

1983-12-01

Assumptions and Scope ........oo......469....... II. Theory of the Resonance Radiation Force ........... 7 .’ Introduction o ..... - ... o7 General Explanation...areas. First, the initial velocity distribution for the atoms are needed. This information is developed in Ramsey’s book (Ref 12). Second, a general ...theory of the interaction of light with an atom is required. A general theory of resonance radiation pressure of light is developed from quantum

Systemic Operational Design: An Alternative to Estimate Planning

DTIC Science & Technology

2009-05-04

relationships found in the COE. Framing and campaign design, with emphasis on systems theory , have therefore made their way to the forefront of doctrinal...short explanation of the systems theory behind SOD, examines how the SOD process happens, and compares SOD with the time proven “Commander’s Estimate... Theory , Campaign planning, Contemporary Operating Environment, Commander’s Estimate Process, Operational design 16. SECURITY CLASSIFICATION OF

Methods to identify, study and understand end-user participation in HIT development.

PubMed

Høstgaard, Anna Marie; Bertelsen, Pernille; Nøhr, Christian

2011-09-28

Experience has shown that for new health-information-technology (HIT) to be suc-cessful clinicians must obtain positive clinical benefits as a result of its implementation and joint-ownership of the decisions made during the development process. A prerequisite for achieving both success criteria is real end-user-participation. Experience has also shown that further research into developing improved methods to collect more detailed information on social groups participating in HIT development is needed in order to support, facilitate and improve real end-user participation. A case study of an EHR planning-process in a Danish county from October 2003 until April 2006 was conducted using process-analysis. Three social groups (physicians, IT-professionals and administrators) were identified and studied in the local, present perspective. In order to understand the interactions between the three groups, the national, historic perspective was included through a literature-study. Data were collected through observations, interviews, insight gathered from documents and relevant literature. In the local, present perspective, the administrator's strategy for the EHR planning process meant that there was no clinical workload-reduction. This was seen as one of the main barriers to the physicians to achieving real influence. In the national, historic perspective, physicians and administrators have had/have different perceptions of the purpose of the patient record and they have both struggled to influence this definition. To date, the administrators have won the battle. This explains the conditions made available for the physicians' participation in this case, which led to their role being reduced to that of clinical consultants--rather than real participants. In HIT-development the interests of and the balance of power between the different social groups involved are decisive in determining whether or not the end-users become real participants in the development process. Real end-user-participation is essential for the successful outcome of the process. By combining and developing existing theories and methods, this paper presents an improved method to collect more detailed information on social groups participating in HIT-development and their interaction during the development. This allows HIT management to explore new avenues during the HIT development process in order to support, facilitate and improve real end-user participation.

Explaining consumer choice: coming to terms with intentionality.

PubMed

Foxall, Gordon R

2007-06-01

Any attempt to understand the nature of behaviorism as a philosophy of science, to depict the essence of its distinctive explanatory system, or to delimit the scope of its capacity to explicate behavior, requires an appreciation of how its practitioners use language. Three behaviorist theories that are especially relevant to the explanation of economic behavior - radical behaviorism, teleological behaviorism, and picoeconomics - provide a necessary array of theoretical perspectives in that each contributes uniquely to understanding consumer choice. Despite the differences that separate them at a methodological level, and the internecine disputes in which their adherents sometimes address one another, these three perspectives play complementary roles in the depiction of everyday consumer behavior. Moreover, this combination of behavior theories owes much to the way in which each has responded to the challenge of intentional explanation. In order to demonstrate this, the paper proposes a framework of analysis which portrays the essential differences between intentional explanation and the extensional approach towards which many behaviorists have striven, and argues that while radical behaviorism scrupulously avoids intentional terms, teleological behaviorism and picoeconomics have in differing ways come to terms with the necessity of combining a behaviorist perspective with the explanatory value of intentional terminology. This continuum of explanations is applied to recent findings of consumer behavior analysis on consumer choice in natural environments.

Are evolutionary hypotheses for motion sickness "just-so" stories?

PubMed

Oman, Charles M

2012-01-01

Vertebrates have evolved rapidly conditionable nausea and vomiting reflexes mediated by gut and brainstem receptors, clearly as a defense against neurotoxin ingestion. In 1977 Treisman proposed that sensory orientation linkages to emetic centers evolved for the same reason, and that motion sickness was an accidental byproduct. It was an "adaptationist" explanation for motion sickness, since it assumed that evolution has shaped all phenotypic traits for survival advantage. Treisman's "poison" theory is plausible, and frequently cited as the accepted scientific explanation for motion sickness. However, alternative explanations have been proposed. The creation of hypotheses is an essential part of science - provided they are testable. This paper reviews the evidence for the Poison theory and several other adaptationist explanations. These hypotheses are certainly not "just-so stories", but supporting evidence is equivocal, and contradictory evidence exists Parsimony suggests an alternative "pluralistic" view: The vertebrate reticular formation maintains oxygenated blood flow to the brain, discriminates unexpected sensory stimuli- including postural disturbances, and detects and expels ingested neurotoxins. The three systems share neuroarchitectural elements but normally function independently. Brainstem sensory conflict neurons normally discriminate brief postural disturbances, but can be abnormally stimulated during prolonged passive transport (e.g. by boat, beginning about 150-200 generations ago). Sensory conflict signals cross couple into the neurotoxin expulsion and avoidance system, producing an arguably maladaptive emetic phenotype.

Toward a mechanistic explanation of phenotypic evolution: The need for a theory of theory integration.

PubMed

Laubichler, Manfred D; Prohaska, Sonja J; Stadler, Peter F

2018-01-01

Reconciling different underlying ontologies and explanatory contexts has been one of the main challenges and impediments for theory integration in biology. Here, we analyze the challenge of developing an inclusive and integrative theory of phenotypic evolution as an example for the broader challenge of developing a theory of theory integration within the life sciences and suggest a number of necessary formal steps toward the resolution of often incompatible (hidden) assumptions. Theory integration in biology requires a better formal understanding of the structure of biological theories The strategy for integrating theories crucially depends on the relationships of the underlying ontologies. © 2018 Wiley Periodicals, Inc.

Investigation of the radiation background in the interaction region of the medium-energy electron relativisitic heavy ion collider (MeRHIC)

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

Beebe-Wang,J.

There are three main sources of the radiation background in MeRHIC: forward synchrotron radiation generated upstream of the detector, the direct backward radiation caused by the photons hitting beampipe downstream of the detector, and the indirect secondary radiation caused by hard photons hitting vacuum systems, masks, collimators, absorbers or any other elements in the interaction region. In this paper, we first calculate the primary radiation distribution by employing electromagnetic theory. Then we obtain the direct backward scattering rate by applying the kinematic Born approximation deduced from scattering dynamics. The diffuse scattering cross section is calculated as a function of themore » surface properties of the MeRHIC vacuum system. Finally, the dominating physical processes and minimization of indirect secondary radiation is presented and discussed.« less

The Mistaken Birth and Adoption of LNT: An Abridged Version

PubMed Central

Calabrese, Edward J.

2017-01-01

The historical foundations of cancer risk assessment were based on the discovery of X-ray-induced gene mutations by Hermann J. Muller, its transformation into the linear nonthreshold (LNT) single-hit theory, the recommendation of the model by the US National Academy of Sciences, Biological Effects of Atomic Radiation I, Genetics Panel in 1956, and subsequent widespread adoption by regulatory agencies worldwide. This article summarizes substantial recent historical revelations of this history, which profoundly challenge the standard and widely acceptable history of cancer risk assessment, showing multiple significant scientific errors and incorrect interpretations, mixed with deliberate misrepresentation of the scientific record by leading ideologically motivated radiation geneticists. These novel historical findings demonstrate that the scientific foundations of the LNT single-hit model were seriously flawed and should not have been adopted for cancer risk assessment. PMID:29051718

Monte Carlo study of microdosimetric diamond detectors

NASA Astrophysics Data System (ADS)

Solevi, Paola; Magrin, Giulio; Moro, Davide; Mayer, Ramona

2015-09-01

Ion-beam therapy provides a high dose conformity and increased radiobiological effectiveness with respect to conventional radiation-therapy. Strict constraints on the maximum uncertainty on the biological weighted dose and consequently on the biological weighting factor require the determination of the radiation quality, defined as the types and energy spectra of the radiation at a specific point. However the experimental determination of radiation quality, in particular for an internal target, is not simple and the features of ion interactions and treatment delivery require dedicated and optimized detectors. Recently chemical vapor deposition (CVD) diamond detectors have been suggested as ion-beam therapy microdosimeters. Diamond detectors can be manufactured with small cross sections and thin shapes, ideal to cope with the high fluence rate. However the sensitive volume of solid state detectors significantly deviates from conventional microdosimeters, with a diameter that can be up to 1000 times the height. This difference requires a redefinition of the concept of sensitive thickness and a deep study of the secondary to primary radiation, of the wall effects and of the impact of the orientation of the detector with respect to the radiation field. The present work intends to study through Monte Carlo simulations the impact of the detector geometry on the determination of radiation quality quantities, in particular on the relative contribution of primary and secondary radiation. The dependence of microdosimetric quantities such as the unrestricted linear energy L and the lineal energy y are investigated for different detector cross sections, by varying the particle type (carbon ions and protons) and its energy.

Gravity in the Century of Light: The Gravitation Theory of Georges-Louis Le Sage

NASA Astrophysics Data System (ADS)

Evans, James

2006-05-01

Each generation of physicists, or natural philosophers, has sought to place universal gravitation in the context of its own worldview. Often this has entailed an effort to reduce gravitation to something more fundamental. But what is deemed fundamental has, of course, changed with time. Each generation attacked the problem of universal gravitation with the tools of its day and brought to bear the concepts of its own standard model. The most successful eighteenth-century attempt to provide a mechanical explanation of gravity was that of Georges-Louis Le Sage (1724-1803) of Geneva. Le Sage postulated a sea of ultramundane corpuscles, streaming in all directions and characterized by minute mass, great velocity, and complete inelasticity. Mostly these corpuscles just pass through gross bodies such as apples or planets, but a few are absorbed, leading to all the phenomena of attraction. In a voluminous correspondence with nearly all the savants of the day, Le Sage constantly reshaped his arguments for his system in order to appeal to metaphysicians, mechanicians and Newtonians of several varieties. Le Sage's theory is an especially interesting one, for several reasons. First, it serves as the prototype of a dynamical explanation of Newtonian gravity. Second, the theory came quite close to accomplishing its aim. Third, the theory had a long life and attracted comment by the leading physical thinkers of several successive generations, including Laplace, Kelvin, Maxwell and Feynman. Le Sage's theory therefore provides an excellent opportunity for the study of the evolution of attitudes toward physical explanation. The effects of national style in science and generational change take on a new clarity.

Using technology to engage hospitalised patients in their care: a realist review.

PubMed

Roberts, Shelley; Chaboyer, Wendy; Gonzalez, Ruben; Marshall, Andrea

2017-06-06

Patient participation in health care is associated with improved outcomes for patients and hospitals. New technologies are creating vast potential for patients to participate in care at the bedside. Several studies have explored patient use, satisfaction and perceptions of health information technology (HIT) interventions in hospital. Understanding what works for whom, under what conditions, is important when considering interventions successfully engaging patients in care. This realist review aimed to determine key features of interventions using bedside technology to engage hospital patients in their care and analyse these in terms of context, mechanisms and outcomes. A realist review was chosen to explain how and why complex HIT interventions work or fail within certain contexts. The review was guided by Pawson's realist review methodology, involving: clarifying review scope; searching for evidence; data extraction and evidence appraisal; synthesising evidence and drawing conclusions. Author experience and an initial literature scope provided insight and review questions and theories (propositions) around why interventions worked were developed and iteratively refined. A purposive search was conducted to find evidence to support, refute or identify further propositions, which formed an explanatory model. Each study was 'mined' for evidence to further develop the propositions and model. Interactive learning was the overarching theme of studies using technology to engage patients in their care. Several propositions underpinned this, which were labelled: information sharing; self-assessment and feedback; tailored education; user-centred design; and support in use of HIT. As studies were mostly feasibility or usability studies, they reported patient-centred outcomes including patient acceptability, satisfaction and actual use of HIT interventions. For each proposition, outcomes were proposed to come about by mechanisms including improved communication, shared decision-making, empowerment and self-efficacy; which acted as facilitators to patient participation in care. Overall, there was a stronger representation of health than IT disciplines in studies reviewed, with a lack of IT input in terms of theoretical underpinning, methodological design and reporting of outcomes. HIT interventions have great potential for engaging hospitalised patients in their care. However, stronger interdisciplinary collaboration between health and IT researchers is needed for effective design and evaluation of HIT interventions.

Societal Unity of Effort, a Fork in the Road to Development or Disaster -- Considerations for State Building

DTIC Science & Technology

2006-05-25

This places it somewhere between the Structuralist and Dependency schools. International Political Economy theory balances between the Marxist and...does not portend to provide that explanation, but rather seeks to provide considerations for study in developmental theory and for United States...of globalization. Historic and contemporary developmental theories are insufficient in that they fail to account for societal characteristics in

Why was Relativity Accepted?

NASA Astrophysics Data System (ADS)

Brush, S. G.

Historians of science have published many studies of the reception of Einstein's special and general theories of relativity. Based on a review of these studies, and my own research on the role of the light-bending prediction in the reception of general relativity, I discuss the role of three kinds of reasons for accepting relativity (1) empirical predictions and explanations; (2) social-psychological factors; and (3) aesthetic-mathematical factors. According to the historical studies, acceptance was a three-stage process. First, a few leading scientists adopted the special theory for aesthetic-mathematical reasons. In the second stage, their enthusiastic advocacy persuaded other scientists to work on the theory and apply it to problems currently of interest in atomic physics. The special theory was accepted by many German physicists by 1910 and had begun to attract some interest in other countries. In the third stage, the confirmation of Einstein's light-bending prediction attracted much public attention and forced all physicists to take the general theory of relativity seriously. In addition to light-bending, the explanation of the advance of Mercury's perihelion was considered strong evidence by theoretical physicists. The American astronomers who conducted successful tests of general relativity became defenders of the theory. There is little evidence that relativity was `socially constructed' but its initial acceptance was facilitated by the prestige and resources of its advocates.

Effects of TEL Confusers on Operator Target Acquisition Performance with SAR Imagery

DTIC Science & Technology

1998-12-01

processing known as the theory of signal detection (TSD) (Gescheider, 1985; Green & Swets, 1966; Macmillan & Creelman , 1991; Wilson, 1992). A TSD...localizations (Hacker & Ratcliff, 1979; Macmillan & Creelman , 1991). The index of bias in a target localization task provides a measure of the operator’s...of correct localizations substituted for hits (Macmillan & Creelman , 1991). Receiver Operating Characteristic Curves. In addition to the calculation

Automatic Target Cueing and Operator Performance with Enhanced APG-70 Synthetic Aperture Radar Imagery.

DTIC Science & Technology

1997-11-01

tasks (Gescheider, 1985; Green & Swets, 1966; Macmillan & Creelman , 1991; See & Kuperman, 1995; See, Riegler, Fitzhugh, & Kuperman, 1996; See, Warm...available for designation and the operator’s ensuing proportion of correct localization responses (Hacker & Ratcliff, 1979; Macmillan & Creelman ...substituted for hits (Macmillan & Creelman , 1991). The Present Study The techniques of signal detection theory were applied in the present study in

Theory of Mind and Emotion Regulation Difficulties in Adolescents with Borderline Traits

ERIC Educational Resources Information Center

Sharp, Carla; Pane, Heather; Ha, Carolyn; Venta, Amanda; Patel, Amee B.; Sturek, Jennifer; Fonagy, Peter

2011-01-01

Objective: Dysfunctions in both emotion regulation and social cognition (understanding behavior in mental state terms, theory of mind or mentalizing) have been proposed as explanations for disturbances of interpersonal behavior in borderline personality disorder (BPD). This study aimed to examine mentalizing in adolescents with emerging BPD from a…

For Whom Is a Picture Worth a Thousand Words? Extensions of a Dual-Coding Theory of Multimedia Learning.

ERIC Educational Resources Information Center

Mayer, Richard E.; Sims, Valerie K.

1994-01-01

In 2 experiments, 162 high- and low-spatial ability students viewed a computer-generated animation and heard a concurrent or successive explanation. The concurrent group generated more creative solutions to transfer problems and demonstrated a contiguity effect consistent with dual-coding theory. (SLD)

Chomsky, Syntax, and Reading: A Primer for Teachers.

ERIC Educational Resources Information Center

Kolczynski, Richard G.

Noam Chomsky's theory of grammar, or more specifically his theory of syntax, proposes to describe all possible English sentences through an explanation of how the native speaker generates sentences. It is the study of one's competence that offers insights into how language is acquired and how the rules and generalizations of that language are…

Serendipity in the Theater: Maude Adams as James M. Barrie's American Muse.

ERIC Educational Resources Information Center

Diaz de Chumaceiro, Cora L.

2003-01-01

This essay discusses how Maude Adams influenced James M. Barrie's creative process and became his inspiration. Set change theory is underscored as a cognitive explanation for Barrie's illumination. The psychoanalytic theory of transference is proposed as an underlying mechanism for facilitating the change of mental set during the incubation stage.…

Norms Inform Mental State Ascriptions: A Rational Explanation for the Side-Effect Effect

ERIC Educational Resources Information Center

Uttich, Kevin; Lombrozo, Tania

2010-01-01

Theory of mind, the capacity to understand and ascribe mental states, has traditionally been conceptualized as analogous to a scientific theory. However, recent work in philosophy and psychology has documented a "side-effect effect" suggesting that moral evaluations influence mental state ascriptions, and in particular whether a behavior is…

Enhancing Subjective Well-Being in Individuals with Asthma

ERIC Educational Resources Information Center

Bray, Melissa A.; Kehle, Thomas J.; Peck, Heather L.; Theodore, Lea A.; Zhou, Zheng

2004-01-01

Asthma, a chronic respiratory disease, is caused by a complex interaction between genetic and environmental variables. The intent of this article is to propose a theory that provides an explanation for the reduction of emotionally triggered asthma through treatments derived from positive psychology. The basic tenet of the theory is that physical…

Developmental roots of episodic memory.

PubMed

Nelson, Katherine

2018-01-01

Two arguments imply that Mahr & Csibra's (M&C's) functional theory is insufficient as an explanation of episodic memory: (1) The developmental course supports a different social cultural division of episodic and semantic memory, and (2) the existence of long-term autobiographical memory is not explained in the functional theory but can be seen in a broader cultural framework.

Leadership, Organizational, and Institutional Studies: Reconciling and Teaching Competing Perspectives

ERIC Educational Resources Information Center

Shoup, John R.

2016-01-01

Leadership, organizational, and institutional theories provide competing explanations on the nature of leadership and role of leaders. Part of the problem is that each theory is often studied in isolation, leading to incomplete perspectives on the essence of leadership in value driven contexts. A holistic paradigm that blends the three dominant…

General Strain Theory and Delinquency: Extending a Popular Explanation to American Indian Youth

ERIC Educational Resources Information Center

Eitle, David; Eitle, Tamela McNulty

2016-01-01

Despite evidence that American Indian (AI) adolescents are disproportionately involved in crime and delinquent behavior, there exists scant research exploring the correlates of crime among this group. We posit that Agnew's General Strain Theory (GST) is well suited to explain AI delinquent activity. Using the National Longitudinal Study of…

Social Exchange Theory as an Explanation of Organizational Citizenship Behaviour among Teachers

ERIC Educational Resources Information Center

Elstad, Eyvind; Christophersen, Knut Andreas; Turmo, Are

2011-01-01

Primary processes in schools are hard to pin down despite attempts to measure central aspects of processes and outputs. For this very reason, it is important that teachers are motivated to go above and beyond their formal job responsibilities, a phenomenon called organizational citizenship behaviour. Social exchange theory is a theoretical…

Inclusive Education: Teachers' Intentions and Behaviour Analysed from the Viewpoint of the Theory of Planned Behaviour

ERIC Educational Resources Information Center

Yan, Zi; Sin, Kuen-fung

2014-01-01

The theory of planned behaviour (TPB) claims that behaviour can be predicted by behavioural intention and perceived behavioural control, while behavioural intention is a function of attitude towards the behaviour, subjective norm, and perceived behavioural control. This study aims at providing explanation and prediction of teachers' inclusive…

Function and Functional Explanation in Social Capital Theory: A Philosophical Appraisal

ERIC Educational Resources Information Center

Vorhaus, John

2014-01-01

Social capital is frequently offered up as a variable to explain such educational outcomes as academic attainment, drop-out rates and cognitive development. Yet, despite its popularity amongst social scientists, social capital theory remains the object of some scepticism, particularly in respect of its explanatory ambitions. I provide an account…

Divisions of Domestic Work: Revising and Expanding the Theoretical Explanations

ERIC Educational Resources Information Center

Kroska, Amy

2004-01-01

Using a sample of 101 heterosexual, co-residential couples, the author evaluates four housework theories: gender ideology, relative resources, time availability, and doing gender. Unlike some tests of these theories, the author operationalizes gender ideology as an identity, and the author tests the models on the traditionally feminine chores as…

An Item Response Theory Model for Test Bias.

ERIC Educational Resources Information Center

Shealy, Robin; Stout, William

This paper presents a conceptualization of test bias for standardized ability tests which is based on multidimensional, non-parametric, item response theory. An explanation of how individually-biased items can combine through a test score to produce test bias is provided. It is contended that bias, although expressed at the item level, should be…

How Employees Remain Happy: Explaining a Paradox

ERIC Educational Resources Information Center

Hutton, Dorothy M.; Atkinson, Barbara; Judd, Priya; Darling, Julie; Tran, Linh; Cummins, Robert A.

2004-01-01

This paper draws on subjective quality of life theory to explain findings from three studies of quality of work life. The studies were conducted with 346 regional process workers, metropolitan employment officers and nurses. The results support the adoption of the theory of homeostasis as an explanation for findings on subjective wellbeing at work…

State of the Universe. If Not with a Big Bang, Then What?

ERIC Educational Resources Information Center

Peterson, Ivars

1991-01-01

The Big Bang Theory and alternatives to the Big Bang Theory as an explanation for the origin of the universe are discussed. The importance of the discovery of redshift, the percentage of hydrogen found in old stars, and the existence of a uniform sea of radiation are explained. (KR)

Appropriateness of Condom Use among College Students: A Social Cognitive Theory Based Explanation.

ERIC Educational Resources Information Center

Schuster, Catherine

2000-01-01

Surveyed college students using 12 selected components of social cognitive theory (SCT) to identify factors related to appropriate use of male condoms during vaginal intercourse. Results indicated that 8 of the 12 SCT constructs significantly correlated with appropriateness of condom use. Factors that affected appropriate condom use behavior were…

Rule-Based Reasoning Is Fast and Belief-Based Reasoning Can Be Slow: Challenging Current Explanations of Belief-Bias and Base-Rate Neglect

ERIC Educational Resources Information Center

Newman, Ian R.; Gibb, Maia; Thompson, Valerie A.

2017-01-01

It is commonly assumed that belief-based reasoning is fast and automatic, whereas rule-based reasoning is slower and more effortful. Dual-Process theories of reasoning rely on this speed-asymmetry explanation to account for a number of reasoning phenomena, such as base-rate neglect and belief-bias. The goal of the current study was to test this…

Cultural border crossing: The interaction between fundamental Christian beliefs and scientific explanations

NASA Astrophysics Data System (ADS)

Elimbi, Celestine Nakeli

The purpose of this study is to investigate the interaction between people's fundamental Christian beliefs and scientific explanations. When people with fundamental Christian beliefs encounter scientific explanations, such explanations may interact with their deeply rooted beliefs in a way that is likely to produce tensions. It is expedient to understand the classroom/professional experiences of such individuals and how they manage these tensions. I will apply Jegede's collateral learning theory as a lens to look at how individuals manage the tensions between their religious and scientific worldviews. Gaining insight into people's experiences in the classroom/work place and how they manage these tensions will potentially inform classroom instruction and ways by which we can help students with fundamental Christian beliefs maintain their pursuit of science related careers by easing the nature of the borders they cross. Sources of data will include participant reported perspectives of how they manage the tensions and observations of real-time resolution of potentially conflicting explanations from their religious and scientific worldviews.

Race, intelligence and political efficacy among school children.

PubMed

Carmines, E G; Baxter, D J

1986-01-01

This paper focuses on the difference in political efficacy found between black and white pre-adults, and assesses a specific explanation of this racial difference, one that combines elements of the intelligence explanation with aspects of the social-deprivation explanation as outlined by Paul Abramson. The explanation suggests that the racial difference in feelings of political effectiveness is due to intelligence which, in turn, is basically a function of the social and economic environment. Focusing on a study of 421 black and white students, it is shown that the predictions from the theory are empirically valid. Most importantly, it is demonstrated that once intelligence is controlled for, there is little or no relationship between race and political efficacy--that is, the black and white students are approximately equal in their levels of political effectiveness. Thus the study lends empirical support to this particular explanation of the racial difference in political efficacy, and suggests, more generally, that intelligence may play a significant role in the political socialization process.

Landquake dynamics inferred from seismic source inversion: Greenland and Sichuan events of 2017

NASA Astrophysics Data System (ADS)

Chao, W. A.

2017-12-01

In June 2017 two catastrophic landquake events occurred in Greenland and Sichuan. The Greenland event leads to tsunami hazard in the small town of Nuugaarsiaq. A landquake in Sichuan hit the town, which resulted in over 100 death. Both two events generated the strong seismic signals recorded by the real-time global seismic network. I adopt an inversion algorithm to derive the landquake force time history (LFH) using the long-period waveforms, and the landslide volume ( 76 million m3) can be rapidly estimated, facilitating the tsunami-wave modeling for early warning purpose. Based on an integrated approach involving tsunami forward simulation and seismic waveform inversion, this study has significant implications to issuing actionable warnings before hazardous tsunami waves strike populated areas. Two single-forces (SFs) mechanism (two block model) yields the best explanation for Sichuan event, which demonstrates that secondary event (seismic inferred volume: 8.2 million m3) may be mobilized by collapse-mass hitting from initial rock avalanches ( 5.8 million m3), likely causing a catastrophic disaster. The later source with a force magnitude of 0.9967×1011 N occurred 70 seconds after first mass-movement occurrence. In contrast, first event has the smaller force magnitude of 0.8116×1011 N. In conclusion, seismically inferred physical parameters will substantially contribute to improving our understanding of landquake source mechanisms and mitigating similar hazards in other parts of the world.

Time-dependent Models of Magnetospheric Accretion onto Young Stars

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

Robinson, C. E.; Espaillat, C. C.; Owen, J. E.

Accretion onto Classical T Tauri stars is thought to take place through the action of magnetospheric processes, with gas in the inner disk being channeled onto the star’s surface by the stellar magnetic field lines. Young stars are known to accrete material in a time-variable manner, and the source of this variability remains an open problem, particularly on the shortest (∼day) timescales. Using one-dimensional time-dependent numerical simulations that follow the field line geometry, we find that for plausibly realistic young stars, steady-state transonic accretion occurs naturally in the absence of any other source of variability. However, we show that ifmore » the density in the inner disk varies smoothly in time with ∼day-long timescales (e.g., due to turbulence), this complication can lead to the development of shocks in the accretion column. These shocks propagate along the accretion column and ultimately hit the star, leading to rapid, large amplitude changes in the accretion rate. We argue that when these shocks hit the star, the observed time dependence will be a rapid increase in accretion luminosity, followed by a slower decline, and could be an explanation for some of the short-period variability observed in accreting young stars. Our one-dimensional approach bridges previous analytic work to more complicated multi-dimensional simulations and observations.« less

Application of theory to family-centered care: a role for social workers.

PubMed

Miller, Gary

2012-01-01

Family-centered care is an emerging trend in health care settings today. An explanation, principles, and a definition of family-centered care are offered and discussed. A theoretical framework, Balance Theory of Coordination, which can be utilized by social workers to develop and enhance family-centered care practices, is explained and discussed. Various family-centered care practices are examined within the context of Balance Theory of Coordination as examples.

Putting Theory of Mind in Its Place: Psychological Explanations of the Socio-Emotional-Communicative Impairments in Autistic Spectrum Disorder

ERIC Educational Resources Information Center

Boucher, Jill

2012-01-01

In this review, the history of the theory of mind (ToM) theory of autistic spectrum disorder (ASD) is outlined (in which ToM is indexed by success on false belief tasks), and the explanatory power and psychological causes of impaired ToM in ASD are critically discussed. It is concluded that impaired ToM by itself has only limited explanatory…

Particularism and the retreat from theory in the archaeology of agricultural origins

PubMed Central

Gremillion, Kristen J.; Barton, Loukas; Piperno, Dolores R.

2014-01-01

The introduction of new analytic methods and expansion of research into previously untapped regions have greatly increased the scale and resolution of data relevant to the origins of agriculture (OA). As a result, the recognition of varied historical pathways to agriculture and the continuum of management strategies have complicated the search for general explanations for the transition to food production. In this environment, higher-level theoretical frameworks are sometimes rejected on the grounds that they force conclusions that are incompatible with real-world variability. Some of those who take this position argue instead that OA should be explained in terms of local and historically contingent factors. This retreat from theory in favor of particularism is based on the faulty beliefs that complex phenomena such as agricultural origins demand equally complex explanations and that explanation is possible in the absence of theoretically based assumptions. The same scholars who are suspicious of generalization are reluctant to embrace evolutionary approaches to human behavior on the grounds that they are ahistorical, overly simplistic, and dismissive of agency and intent. We argue that these criticisms are misplaced and explain why a coherent theory of human behavior that acknowledges its evolutionary history is essential to advancing understanding of OA. Continued progress depends on the integration of human behavior and culture into the emerging synthesis of evolutionary developmental biology that informs contemporary research into plant and animal domestication. PMID:24753601

Motivation and burnout among top amateur rugby players.

PubMed

Cresswell, Scott L; Eklund, Robert C

2005-03-01

Self-determination theory has proven to be a useful theoretical explanation of the occurrence of ill-being on a variety of accounts. Self-determination theory may also provide a useful explanation of the occurrence of athlete burnout. To date, limited evidence exists to support links between motivation and burnout. To examine relationships and potential causal directions among burnout and types of motivation differing in degree of self-determination. Data were collected on burnout using the Athlete Burnout Questionnaire and Sport Motivation Scale from 392 top amateur male rugby players. Structural equation modeling procedures were employed to evaluate a measurement model and three conceptually grounded structural models. One conceptual model specified concomitant (noncausal) relationships between burnout and motivations varying in self-determination. The other conceptual models specified causal pathways between burnout and the three motivation variables considered in the investigation (i.e., intrinsic motivation, external regulation, and amotivation). Within the models, amotivation, the least self-determined type of motivation, had a large positive association with burnout. Externally regulated motivation had trivial and nonsignificant relationships with burnout. Self-determined forms of motivation (i.e., intrinsic motivation) exhibited significant negative associations with burnout. Overall the results support the potential utility of a self-determination theory explanation of burnout. As all models displayed reasonable and comparable fits, further research is required to establish the nature (concomitant vs directional causal vs reciprocal causal) of the relationship between burnout and motivation.

Particularism and the retreat from theory in the archaeology of agricultural origins.

PubMed

Gremillion, Kristen J; Barton, Loukas; Piperno, Dolores R

2014-04-29

The introduction of new analytic methods and expansion of research into previously untapped regions have greatly increased the scale and resolution of data relevant to the origins of agriculture (OA). As a result, the recognition of varied historical pathways to agriculture and the continuum of management strategies have complicated the search for general explanations for the transition to food production. In this environment, higher-level theoretical frameworks are sometimes rejected on the grounds that they force conclusions that are incompatible with real-world variability. Some of those who take this position argue instead that OA should be explained in terms of local and historically contingent factors. This retreat from theory in favor of particularism is based on the faulty beliefs that complex phenomena such as agricultural origins demand equally complex explanations and that explanation is possible in the absence of theoretically based assumptions. The same scholars who are suspicious of generalization are reluctant to embrace evolutionary approaches to human behavior on the grounds that they are ahistorical, overly simplistic, and dismissive of agency and intent. We argue that these criticisms are misplaced and explain why a coherent theory of human behavior that acknowledges its evolutionary history is essential to advancing understanding of OA. Continued progress depends on the integration of human behavior and culture into the emerging synthesis of evolutionary developmental biology that informs contemporary research into plant and animal domestication.

The picture superiority effect in associative recognition.

PubMed

Hockley, William E

2008-10-01

The picture superiority effect has been well documented in tests of item recognition and recall. The present study shows that the picture superiority effect extends to associative recognition. In three experiments, students studied lists consisting of random pairs of concrete words and pairs of line drawings; then they discriminated between intact (old) and rearranged (new) pairs of words and pictures at test. The discrimination advantage for pictures over words was seen in a greater hit rate for intact picture pairs, but there was no difference in the false alarm rates for the two types of stimuli. That is, there was no mirror effect. The same pattern of results was found when the test pairs consisted of the verbal labels of the pictures shown at study (Experiment 4), indicating that the hit rate advantage for picture pairs represents an encoding benefit. The results have implications for theories of the picture superiority effect and models of associative recognition.

Folk-Psychological Interpretation of Human vs. Humanoid Robot Behavior: Exploring the Intentional Stance toward Robots.

PubMed

Thellman, Sam; Silvervarg, Annika; Ziemke, Tom

2017-01-01

People rely on shared folk-psychological theories when judging behavior. These theories guide people's social interactions and therefore need to be taken into consideration in the design of robots and other autonomous systems expected to interact socially with people. It is, however, not yet clear to what degree the mechanisms that underlie people's judgments of robot behavior overlap or differ from the case of human or animal behavior. To explore this issue, participants ( N = 90) were exposed to images and verbal descriptions of eight different behaviors exhibited either by a person or a humanoid robot. Participants were asked to rate the intentionality, controllability and desirability of the behaviors, and to judge the plausibility of seven different types of explanations derived from a recently proposed psychological model of lay causal explanation of human behavior. Results indicate: substantially similar judgments of human and robot behavior, both in terms of (1a) ascriptions of intentionality/controllability/desirability and in terms of (1b) plausibility judgments of behavior explanations; (2a) high level of agreement in judgments of robot behavior - (2b) slightly lower but still largely similar to agreement over human behaviors; (3) systematic differences in judgments concerning the plausibility of goals and dispositions as explanations of human vs. humanoid behavior. Taken together, these results suggest that people's intentional stance toward the robot was in this case very similar to their stance toward the human.

Relations of alpine plant communities across environmental gradients: Multilevel versus multiscale analyses

USGS Publications Warehouse

Malanson, George P.; Zimmerman, Dale L.; Kinney, Mitch; Fagre, Daniel B.

2017-01-01

Alpine plant communities vary, and their environmental covariates could influence their response to climate change. A single multilevel model of how alpine plant community composition is determined by hierarchical relations is compared to a separate examination of those relations at different scales. Nonmetric multidimensional scaling of species cover for plots in four regions across the Rocky Mountains created dependent variables. Climate variables are derived for the four regions from interpolated data. Plot environmental variables are measured directly and the presence of thirty-seven site characteristics is recorded and used to create additional independent variables. Multilevel and best subsets regressions are used to determine the strength of the hypothesized relations. The ordinations indicate structure in the assembly of plant communities. The multilevel analyses, although revealing significant relations, provide little explanation; of the site variables, those related to site microclimate are most important. In multiscale analyses (whole and separate regions), different variables are better explanations within the different regions. This result indicates weak environmental niche control of community composition. The weak relations of the structure in the patterns of species association to the environment indicates that either alpine vegetation represents a case of the neutral theory of biogeography being a valid explanation or that it represents disequilibrium conditions. The implications of neutral theory and disequilibrium explanations are similar: Response to climate change will be difficult to quantify above equilibrium background turnover.

A World-System Approach to Post-Catastrophe International Relief

ERIC Educational Resources Information Center

Letukas, Lynn; Barnshaw, John

2008-01-01

As our understanding of disaster shifts from an event concentrated in time and space to a social occasion occurring across time and space, so too must our explanations of disaster shift from theories of the middle range to broader theoretical frameworks. We explore the world-system approach in an effort to understand the upper limits of theory for…

Similarities and Dissimilarities in Coauthorship Networks: Gestalt Theory as Explanation for Well-Ordered Collaboration Structures and Production of Scientific Literature.

ERIC Educational Resources Information Center

Kretschmer, Hildrun

2002-01-01

Based on Gestalt theory, the author assumes the existence of a field-force equilibrium to explain how, according to the conciseness principle, mathematically precise gestalts could exist in coauthorship networks. Develops a mathematical function to describe these gestalts in scientific literature and discusses structural characteristics of…

Cohorts and Relatedness: Self-Determination Theory as an Explanation of How Learning Communities Affect Educational Outcomes

ERIC Educational Resources Information Center

Beachboard, Martine Robinson; Beachboard, John C.; Li, Wenling; Adkison, Stephen R.

2011-01-01

This study examines whether feelings of relatedness constitute a substantial means by which learning communities (cohorts) improve learning outcomes in higher education. It applies Ryan and Deci's Self-Determination Theory to an analysis of the National Survey of Student Engagement. The SDT hypothesizes that environments that support perceptions…

The Research Potential of Educational Theory: On the Specific Characteristics of the Issues of Education

ERIC Educational Resources Information Center

Les, Tomasz

2017-01-01

In this article, I present the argument that educational theory has specific character, which distinguishes it from most scientific disciplines. It requires the application of not only strictly scientific methods, which essentially consist of descriptions and explanations, but also normative ones, which indicate how it is related to philosophy and…

Pragmatic Choices: Teaching Applied Aesthetics through Brecht's "Life of Galileo"

ERIC Educational Resources Information Center

Stewart, Robert Scott; Nicholls, Rod

2002-01-01

Aesthetics, as a distinctively "philosophical" exercise, whether with respect to research or to teaching, is supposed to be about the "theory/theories" that underpin the works of art in these various fields. Given this, "applied aesthetics" demands a preliminary explanation. First of all, the phrase might refer to an analysis of a particular work…

Dual Coding Theory, Word Abstractness, and Emotion: A Critical Review of Kousta et al. (2011)

ERIC Educational Resources Information Center

Paivio, Allan

2013-01-01

Kousta, Vigliocco, Del Campo, Vinson, and Andrews (2011) questioned the adequacy of dual coding theory and the context availability model as explanations of representational and processing differences between concrete and abstract words. They proposed an alternative approach that focuses on the role of emotional content in the processing of…

Semantic Relevance, Domain Specificity and the Sensory/Functional Theory of Category-Specificity

ERIC Educational Resources Information Center

Sartori, Giuseppe; Gnoato, Francesca; Mariani, Ilenia; Prioni, Sara; Lombardi, Luigi

2007-01-01

According to the sensory/functional theory of semantic memory, Living items rely more on Sensory knowledge than Non-living ones. The sensory/functional explanation of category-specificity assumes that semantic features are organised on the basis of their content. We report here a study on DAT patients with impaired performance on Living items and…

Theoretical parallels between the Ponzo illusion and the Wundt-Jastrow illusion.

PubMed

Pick, D F; Pierce, K A

1993-04-01

Misapplied-size-constancy, assimilation, and contrast theories are discussed as explanations for the Wundt-Jastrow and Ponzo illusions. An experiment is reported that questions the need to include a contrast function in the assimilation theory of Pressey and Wilson to account for the Wundt-Jastrow illusion. Several directions for further research are proposed.

Latent Profiles of Risk among a Community Sample of Men: Implications for Sexual Aggression

ERIC Educational Resources Information Center

Greene, Patricia Logan; Davis, Kelly Cue

2011-01-01

Of the proposed theoretical explanations for the perpetration of sexual assault, Malamuth's confluence theory remains the most prominent. Further development of this theory has incorporated alcohol use into the original pathways of impersonal sex and hostile masculinity. This study uses data from a nationwide online survey (n = 289) to examine the…

Relational Regulation Theory: A New Approach to Explain the Link between Perceived Social Support and Mental Health

ERIC Educational Resources Information Center

Lakey, Brian; Orehek, Edward

2011-01-01

Perceived support is consistently linked to good mental health, which is typically explained as resulting from objectively supportive actions that buffer stress. Yet this explanation has difficulty accounting for the often-observed main effects between support and mental health. Relational regulation theory (RRT) hypothesizes that main effects…

Assessment of Theory of Mind in Children with Communication Disorders: Role of Presentation Mode

ERIC Educational Resources Information Center

van Buijsen, Marit; Hendriks, Angelique; Ketelaars, Mieke; Verhoeven, Ludo

2011-01-01

Children with communication disorders have problems with both language and social interaction. The theory-of-mind hypothesis provides an explanation for these problems, and different tests have been developed to test this hypothesis. However, different modes of presentation are used in these tasks, which make the results difficult to compare. In…

Hit discovery and hit-to-lead approaches.

PubMed

Keseru, György M; Makara, Gergely M

2006-08-01

Hit discovery technologies range from traditional high-throughput screening to affinity selection of large libraries, fragment-based techniques and computer-aided de novo design, many of which have been extensively reviewed. Development of quality leads using hit confirmation and hit-to-lead approaches present their own challenges, depending on the hit discovery method used to identify the initial hits. In this paper, we summarize common industry practices adopted to tackle hit-to-lead challenges and review how the advantages and drawbacks of different hit discovery techniques could affect the various issues hit-to-lead groups face.

Synthesizing animal and human behavior research via neural network learning theory.

PubMed

Tryon, W W

1995-12-01

Animal and human research have been "divorced" since approximately 1968. Several recent articles have tried to persuade behavior therapists of the merits of animal research. Three reasons are given concerning why disinterest in animal research is so widespread: (1) functional explanations are given for animals, and cognitive explanations are given for humans; (2) serial symbol manipulating models are used to explain human behavior; and (3) human learning was assumed, thereby removing it as something to be explained. Brain-inspired connectionist neural networks, collectively referred to as neural network learning theory (NNLT), are briefly described, and a spectrum of their accomplishments from simple conditioning through speech is outlined. Five benefits that behavior therapists can derive from NNLT are described. They include (a) enhanced professional identity derived from a comprehensive learning theory, (b) improved interdisciplinary collaboration both clinically and scientifically, (c) renewed perceived relevance of animal research, (d) access to plausible proximal causal mechanisms capable of explaining operant conditioning, and (e) an inherently developmental perspective.

On the interpretation of complex network analysis of language. Comment on "Approaching human language with complex networks" by Jin Cong, Haitao Liu

NASA Astrophysics Data System (ADS)

Čech, Radek

2014-12-01

After a rapid and successful development of the theory of complex networks at the turn of the millennium [1,2], attempts to apply this theory to a language analysis emerged immediately [3,4]. The first results seemed to bring new insights to the functioning of language. Moreover, some authors assumed that this approach can even solve some fundamental problems concerning language evolution [5,6]. However, after a decade of the application of complex network theory to language analysis, the initial expectations have not been fulfilled, in my opinion, and the need for a deeper, linguistically based explanation of observed properties has been still more obvious. Cong and Liu's review [7] can be seen as a successful attempt to clarify the main aspects of this kind of research from the linguistics point of view. However, I see two problematic aspects in their study relating to the nature of the character of explanation.

Development of biological and nonbiological explanations for the Viking label release data. [hydrogen peroxide theory

NASA Technical Reports Server (NTRS)

1980-01-01

The plausibility that hydrogen peroxide, widely distributed within the Mars surface material, was responsible for the evocative response obtained by the Viking Labeled Release (LR) experiment on Mars was investigated. Although a mixture of gamma Fe2O3 and silica sand stimulated the LR nutrient reaction with hydrogen peroxide and reduced the rate of hydrogen decomposition under various storage conditions, the Mars analog soil prepared by the Viking Inorganic Analysis Team to match the Mars analytical data does not cause such effects. Nor is adequate resistance to UV irradiation shown. On the basis of the results and consideration presented while the hydrogen peroxide theory remains the most, if not only, attractive chemical explanation of the LR data, it remains unconvincing on critical points. Until problems concerning the formation and stabilization of hydrogen peroxide on the surface of Mars can be overcome, adhere to the scientific evidence requires serious consideration of the biological theory.

Putting theory of mind in its place: psychological explanations of the socio-emotional-communicative impairments in autistic spectrum disorder.

PubMed

Boucher, Jill

2012-05-01

In this review, the history of the theory of mind (ToM) theory of autistic spectrum disorder (ASD) is outlined (in which ToM is indexed by success on false belief tasks), and the explanatory power and psychological causes of impaired ToM in ASD are critically discussed. It is concluded that impaired ToM by itself has only limited explanatory power, but that explorations of the psychological precursors of impaired ToM have been fruitful in increasing understanding of mindreading impairments in ASD (where 'mindreading' refers those abilities that underlie triadic interaction as well as ToM). It is argued that early explanations of impaired mindreading are untenable for various reasons, but that impairments of dyadic interaction in ASD that could lead to impaired ability to represent others' mental states may be the critical psychological cause, or causes, of impaired ToM. The complexity of causal routes to impaired ToM is emphasized.

A Signal Detection Theory Approach to Evaluating Oculometer Data Quality

NASA Technical Reports Server (NTRS)

Latorella, Kara; Lynn, William, III; Barry, John S.; Kelly, Lon; Shih, Ming-Yun

2013-01-01

Currently, data quality is described in terms of spatial and temporal accuracy and precision [Holmqvist et al. in press]. While this approach provides precise errors in pixels, or visual angle, often experiments are more concerned with whether subjects'points of gaze can be said to be reliable with respect to experimentally-relevant areas of interest. This paper proposes a method to characterize oculometer data quality using Signal Detection Theory (SDT) [Marcum 1947]. SDT classification results in four cases: Hit (correct report of a signal), Miss (failure to report a ), False Alarm (a signal falsely reported), Correct Reject (absence of a signal correctly reported). A technique is proposed where subjects' are directed to look at points in and outside of an AOI, and the resulting Points of Gaze (POG) are classified as Hits (points known to be internal to an AOI are classified as such), Misses (AOI points are not indicated as such), False Alarms (points external to AOIs are indicated as in the AOI), or Correct Rejects (points external to the AOI are indicated as such). SDT metrics describe performance in terms of discriminability, sensitivity, and specificity. This paper presentation will provide the procedure for conducting this assessment and an example of data collected for AOIs in a simulated flightdeck environment.

Clinical picture of heparin-induced thrombocytopenia (HIT) and its differentiation from non-HIT thrombocytopenia.

PubMed

Warkentin, Theodore E

2016-10-28

HIT is an acquired antibody-mediated disorder strongly associated with thrombosis, including microthrombosis secondary to disseminated intravascular dissemination (DIC). The clinical features of HIT are reviewed from the perspective of the 4Ts scoring system for HIT, which emphasises its characteristic timing of onset of thrombocytopenia. HIT antibodies recognize multimolecular complexes of platelet factor 4 (PF4)/heparin. However, a subset of HIT sera recognise PF4 bound to platelet chondroitin sulfate; these antibodies activate platelets in vitro and in vivo even in the absence of heparin, thus explaining: delayed-onset HIT (where HIT begins or worsens after stopping heparin); persisting HIT (where HIT takes several weeks to recover); spontaneous HIT syndrome (a disorder clinically and serologically resembling HIT but without proximate heparin exposure); and fondaparinux-associated HIT (four distinct syndromes featuring thrombocytopenia that begins or worsens during treatment with fondaparinux), with a new patient case presented with ongoing thrombocytopenia (and fatal haemorrhage) during treatment of HIT with fondaparinux, with fondaparinux-dependent platelet activation induced by patient serum ("fondaparinux cross-reactivity"). Ironically, despite existence of fondaparinux-associated HIT, this pentasaccharide anticoagulant is a frequent treatment for HIT (including one used by the author). HIT can be confused with other disorders, including those with a) timing similar to HIT (e. g. abciximab-associated thrombocytopenia of delayed-onset); b) combined thrombocytopenia/thrombosis (e. g. symmetrical peripheral gangrene secondary to acute DIC and shock liver); and c) both timing of onset and thrombosis (e. g. warfarin-associated venous limb gangrene complicating cancer-associated DIC). By understanding clinical and pathophysiological similarities and differences between HIT and non-HIT mimicking disorders, the clinician is better able to make the correct diagnosis.

Refining a self-assessment of informatics competency scale using Mokken scaling analysis.

PubMed

Yoon, Sunmoo; Shaffer, Jonathan A; Bakken, Suzanne

2015-01-01

Healthcare environments are increasingly implementing health information technology (HIT) and those from various professions must be competent to use HIT in meaningful ways. In addition, HIT has been shown to enable interprofessional approaches to health care. The purpose of this article is to describe the refinement of the Self-Assessment of Nursing Informatics Competencies Scale (SANICS) using analytic techniques based upon item response theory (IRT) and discuss its relevance to interprofessional education and practice. In a sample of 604 nursing students, the 93-item version of SANICS was examined using non-parametric IRT. The iterative modeling procedure included 31 steps comprising: (1) assessing scalability, (2) assessing monotonicity, (3) assessing invariant item ordering, and (4) expert input. SANICS was reduced to an 18-item hierarchical scale with excellent reliability. Fundamental skills for team functioning and shared decision making among team members (e.g. "using monitoring systems appropriately," "describing general systems to support clinical care") had the highest level of difficulty, and "demonstrating basic technology skills" had the lowest difficulty level. Most items reflect informatics competencies relevant to all health professionals. Further, the approaches can be applied to construct a new hierarchical scale or refine an existing scale related to informatics attitudes or competencies for various health professions.

On the need for Embodied and Dis-Embodied Cognition

PubMed Central

Dove, Guy

2011-01-01

This essay proposes and defends a pluralistic theory of conceptual embodiment. Our concepts are represented in at least two ways: (i) through sensorimotor simulations of our interactions with objects and events and (ii) through sensorimotor simulations of natural language processing. Linguistic representations are “dis-embodied” in the sense that they are dynamic and multimodal but, in contrast to other forms of embodied cognition, do not inherit semantic content from this embodiment. The capacity to store information in the associations and inferential relationships among linguistic representations extends our cognitive reach and provides an explanation of our ability to abstract and generalize. This theory is supported by a number of empirical considerations, including the large body of evidence from cognitive neuroscience and neuropsychology supporting a multiple semantic code explanation of imageability effects. PMID:21833295

Determinants of Judgments of Explanatory Power: Credibility, Generality, and Statistical Relevance.

PubMed

Colombo, Matteo; Bucher, Leandra; Sprenger, Jan

2017-01-01

Explanation is a central concept in human psychology. Drawing upon philosophical theories of explanation, psychologists have recently begun to examine the relationship between explanation, probability and causality. Our study advances this growing literature at the intersection of psychology and philosophy of science by systematically investigating how judgments of explanatory power are affected by (i) the prior credibility of an explanatory hypothesis, (ii) the causal framing of the hypothesis, (iii) the perceived generalizability of the explanation, and (iv) the relation of statistical relevance between hypothesis and evidence. Collectively, the results of our five experiments support the hypothesis that the prior credibility of a causal explanation plays a central role in explanatory reasoning: first, because of the presence of strong main effects on judgments of explanatory power, and second, because of the gate-keeping role it has for other factors. Highly credible explanations are not susceptible to causal framing effects, but they are sensitive to the effects of normatively relevant factors: the generalizability of an explanation, and its statistical relevance for the evidence. These results advance current literature in the philosophy and psychology of explanation in three ways. First, they yield a more nuanced understanding of the determinants of judgments of explanatory power, and the interaction between these factors. Second, they show the close relationship between prior beliefs and explanatory power. Third, they elucidate the nature of abductive reasoning.

Determinants of Judgments of Explanatory Power: Credibility, Generality, and Statistical Relevance

PubMed Central

Colombo, Matteo; Bucher, Leandra; Sprenger, Jan

2017-01-01

Explanation is a central concept in human psychology. Drawing upon philosophical theories of explanation, psychologists have recently begun to examine the relationship between explanation, probability and causality. Our study advances this growing literature at the intersection of psychology and philosophy of science by systematically investigating how judgments of explanatory power are affected by (i) the prior credibility of an explanatory hypothesis, (ii) the causal framing of the hypothesis, (iii) the perceived generalizability of the explanation, and (iv) the relation of statistical relevance between hypothesis and evidence. Collectively, the results of our five experiments support the hypothesis that the prior credibility of a causal explanation plays a central role in explanatory reasoning: first, because of the presence of strong main effects on judgments of explanatory power, and second, because of the gate-keeping role it has for other factors. Highly credible explanations are not susceptible to causal framing effects, but they are sensitive to the effects of normatively relevant factors: the generalizability of an explanation, and its statistical relevance for the evidence. These results advance current literature in the philosophy and psychology of explanation in three ways. First, they yield a more nuanced understanding of the determinants of judgments of explanatory power, and the interaction between these factors. Second, they show the close relationship between prior beliefs and explanatory power. Third, they elucidate the nature of abductive reasoning. PMID:28928679

Impact of Self-Explanation and Analogical Comparison Support on Learning Processes, Motivation, Metacognition, and Transfer

NASA Astrophysics Data System (ADS)

Richey, J. Elizabeth

Research examining analogical comparison and self-explanation has produced a robust set of findings about learning and transfer supported by each instructional technique. However, it is unclear how the types of knowledge generated through each technique differ, which has important implications for cognitive theory as well as instructional practice. I conducted a pair of experiments to directly compare the effects of instructional prompts supporting self-explanation, analogical comparison, and the study of instructional explanations across a number of fine-grained learning process, motivation, metacognition, and transfer measures. Experiment 1 explored these questions using sequence extrapolation problems, and results showed no differences between self-explanation and analogical comparison support conditions on any measure. Experiment 2 explored the same questions in a science domain. I evaluated condition effects on transfer outcomes; self-reported self-explanation, analogical comparison, and metacognitive processes; and achievement goals. I also examined relations between transfer and self-reported processes and goals. Receiving materials with analogical comparison support and reporting greater levels of analogical comparison were both associated with worse transfer performance, while reporting greater levels of self-explanation was associated with better performance. Learners' self-reports of self-explanation and analogical comparison were not related to condition assignment, suggesting that the questionnaires did not measure the same processes promoted by the intervention, or that individual differences in processing are robust even when learners are instructed to engage in self-explanation or analogical comparison.

A test of Hirschi's social bonding theory: juvenile delinquency in the high schools of Ankara, Turkey.

PubMed

Ozbay, Ozden; Ozcan, Yusuf Ziya

2006-12-01

Travis Hirschi's social bonding theory has mostly been tested in the West. In this study, the theory is tested on juvenile delinquency in a developing country, Turkey. Data were gathered from 1,710 high school students in Ankara by using two-stage stratified cluster sampling. Factor analysis was employed to determine the dimensions of juvenile delinquency (assault, school delinquency, and public disturbance), and regression analysis was used to test the theory. Similar to some other traditional societies, the social bonding theory plays an important role in the explanation of juvenile delinquency in Turkey.

Quantum mechanical energy-based screening of combinatorially generated library of tautomers. TauTGen: a tautomer generator program.

PubMed

Harańczyk, Maciej; Gutowski, Maciej

2007-01-01

We describe a procedure of finding low-energy tautomers of a molecule. The procedure consists of (i) combinatorial generation of a library of tautomers, (ii) screening based on the results of geometry optimization of initial structures performed at the density functional level of theory, and (iii) final refinement of geometry for the top hits at the second-order Möller-Plesset level of theory followed by single-point energy calculations at the coupled cluster level of theory with single, double, and perturbative triple excitations. The library of initial structures of various tautomers is generated with TauTGen, a tautomer generator program. The procedure proved to be successful for these molecular systems for which common chemical knowledge had not been sufficient to predict the most stable structures.

Understanding Genetic Breast Cancer Risk: Processing Loci of the BRCA Gist Intelligent Tutoring System

PubMed Central

Wolfe, Christopher R.; Reyna, Valerie F.; Widmer, Colin L.; Cedillos-Whynott, Elizabeth M.; Brust-Renck, Priscila G; Weil, Audrey M.; Hu, Xiangen

2016-01-01

The BRCA Gist Intelligent Tutoring System helps women understand and make decisions about genetic testing for breast cancer risk. BRCA Gist is guided by Fuzzy-Trace Theory, (FTT) and built using AutoTutor Lite. It responds differently to participants depending on what they say. Seven tutorial dialogues requiring explanation and argumentation are guided by three FTT concepts: forming gist explanations in one’s own words, emphasizing decision-relevant information, and deliberating the consequences of decision alternatives. Participants were randomly assigned to BRCA Gist, a control, or impoverished BRCA Gist conditions removing gist explanation dialogues, argumentation dialogues, or FTT images. All BRCA Gist conditions performed significantly better than controls on knowledge, comprehension, and risk assessment. Significant differences in knowledge, comprehension, and fine-grained dialogue analyses demonstrate the efficacy of gist explanation dialogues. FTT images significantly increased knowledge. Providing more elements in arguments against testing correlated with increased knowledge and comprehension. PMID:28008216

Understanding Genetic Breast Cancer Risk: Processing Loci of the BRCA Gist Intelligent Tutoring System.

PubMed

Wolfe, Christopher R; Reyna, Valerie F; Widmer, Colin L; Cedillos-Whynott, Elizabeth M; Brust-Renck, Priscila G; Weil, Audrey M; Hu, Xiangen

2016-07-01

The BRCA Gist Intelligent Tutoring System helps women understand and make decisions about genetic testing for breast cancer risk. BRCA Gist is guided by Fuzzy-Trace Theory, (FTT) and built using AutoTutor Lite. It responds differently to participants depending on what they say. Seven tutorial dialogues requiring explanation and argumentation are guided by three FTT concepts: forming gist explanations in one's own words, emphasizing decision-relevant information, and deliberating the consequences of decision alternatives. Participants were randomly assigned to BRCA Gist , a control, or impoverished BRCA Gist conditions removing gist explanation dialogues, argumentation dialogues, or FTT images. All BRCA Gist conditions performed significantly better than controls on knowledge, comprehension, and risk assessment. Significant differences in knowledge, comprehension, and fine-grained dialogue analyses demonstrate the efficacy of gist explanation dialogues. FTT images significantly increased knowledge. Providing more elements in arguments against testing correlated with increased knowledge and comprehension.

Transition for Whom? Adolescence Theories with Androcentric Bias

ERIC Educational Resources Information Center

Murty, Lakshmi

1978-01-01

Suggests that theoretical expositions of adolescence have completely ignored the differential effects of industrialization on males and females and have utilized a single explanation for both sexes. (Author/AM)

Fusion of bone marrow-derived cells with cancer cells: metastasis as a secondary disease in cancer

PubMed Central

Pawelek, John M.

2014-01-01

This perspective article highlights the leukocyte-cancer cell hybrid theory as a mechanism for cancer metastasis. Beginning from the first proposal of the theory more than a century ago and continuing today with the first proof for this theory in a human cancer, the hybrid theory offers a unifying explanation for metastasis. In this scenario, leukocyte fusion with a cancer cell is a secondary disease superimposed upon the early tumor, giving birth to a new, malignant cell with a leukocyte-cancer cell hybrid epigenome. PMID:24589183

Power and Attraction to the Counternormative Aspects of Infidelity.

PubMed

Lammers, Joris; Maner, Jon

2016-01-01

Previous research shows that powerful people are more likely than those lacking power to engage in infidelity. One possible explanation holds (a) that power psychologically releases people from the inhibiting effects of social norms and thus increases their appetite for counternormative forms of sexuality. Two alternative explanations are (b) that power increases appetite for any form of sexuality, normative or counternormative, and (c) that power makes men (but not women) seem more attractive to others and thus increases their access to potential mating opportunities. The current research tested these explanations using correlational data from 610 Dutch men and women. Supporting the first explanation, power's relationship with infidelity was statistically mediated by increased attraction to the secrecy associated with infidelity. Inconsistent with the second explanation, power was linked with infidelity but not with casual sex among singles (a more normative form of sexuality). Inconsistent with the third explanation, the link between power and infidelity was observed just as strongly in women as in men. Findings suggest that power may be associated with infidelity because power draws people to the counternormative aspects of infidelity. Implications for theories of power, sexuality, and gender are discussed.

Delusions as performance failures.

PubMed

Gerrans, P

2001-08-01

Delusions are explanations of anomalous experiences. A theory of delusion requires an explanation of both the anomalous experience and the apparently irrational explanation generated by the delusional subject. Hence, we require a model of rational belief formation against which the belief formation of delusional subjects can be evaluated. I first describe such a model, distinguishing procedural from pragmatic rationality. Procedural rationality is the use of rules or procedures, deductive or inductive, that produce an inferentially coherent set of propositions. Pragmatic rationality is the use of procedural rationality in context. I then apply the distinction to the explanation of the Capgras and the Cotard delusions. I then argue that delusions are failures of pragmatic rationality. I examine the nature of these failures employing the distinction between performance and competence familiar from Chomskian linguistics. This approach to the irrationality of delusions reconciles accounts in which the explanation of the anomalous experience exhausts the explanation of delusion, accounts that appeal to further deficits within the reasoning processes of delusional subjects, and accounts that argue that delusions are not beliefs at all. (Respectively, one-stage, two-stage, and expressive accounts.) In paradigm cases that concern cognitive neuropsychiatry the irrationality of delusional subjects should be thought of as a performance deficit in pragmatic rationality.

SU-E-J-03: A Comprehensive Comparison Between Alpha and Beta Emitters for Cancer Radioimmunotherapy

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

Huang, C.Y.; Guatelli, S; Oborn, B

2014-06-01

Purpose: The purpose of this study is to perform a comprehensive comparison of the therapeutic efficacy and cytotoxicity of alpha and beta emitters for Radioimmunotherapy (RIT). For each stage of cancer development, specific models were built for the separate objectives of RIT to be addressed:a) kill isolated cancer cells in transit in the lymphatic and vascular circulation,b) regress avascular cell clusters,c) regress tumor vasculature and tumors. Methods: Because of the nature of short range, high LET alpha and long energy beta radiation and heterogeneous antigen expression among cancer cells, the microdosimetric approach is essential for the RIT assessment. Geant4 basedmore » microdosimetric models are developed for the three different stages of cancer progression: cancer cells, cell clusters and tumors. The energy deposition, specific energy resulted from different source distribution in the three models was calculated separately for 4 alpha emitting radioisotopes ({sup 211}At, {sup 213}Bi, {sup 223}Ra and {sup 225}Ac) and 6 beta emitters ({sup 32}P, {sup 33}P, {sup 67}Cu, {sup 90}Y, {sup 131}I and {sup 177}Lu). The cell survival, therapeutic efficacy and cytotoxicity are determined and compared between alpha and beta emitters. Results: We show that internal targeted alpha radiation has advantages over beta radiation for killing isolated cancer cells, regressing small cell clusters and also solid tumors. Alpha particles have much higher dose specificity and potency than beta particles. They can deposit 3 logs more dose than beta emitters to single cells and solid tumor. Tumor control probability relies on deep penetration of radioisotopes to cancer cell clusters and solid tumors. Conclusion: The results of this study provide a quantitative understanding of the efficacy and cytotoxicity of RIT for each stage of cancer development.« less

Dosimetric and microdosimetric analyses for blood exposed to reactor-derived thermal neutrons.

PubMed

Ali, F; Atanackovic, J; Boyer, C; Festarini, A; Kildea, J; Paterson, L C; Rogge, R; Stuart, M; Richardson, R B

2018-06-06

Thermal neutrons are found in reactor, radiotherapy, aircraft, and space environments. The purpose of this study was to characterise the dosimetry and microdosimetry of thermal neutron exposures, using three simulation codes, as a precursor to quantitative radiobiological studies using blood samples. An irradiation line was designed employing a pyrolytic graphite crystal or-alternatively-a super mirror to expose blood samples to thermal neutrons from the National Research Universal reactor to determine radiobiological parameters. The crystal was used when assessing the relative biological effectiveness for dicentric chromosome aberrations, and other biomarkers, in lymphocytes over a low absorbed dose range of 1.2-14 mGy. Higher exposures using a super mirror will allow the additional quantification of mitochondrial responses. The physical size of the thermal neutron fields and their respective wavelength distribution was determined using the McStas Monte Carlo code. Spinning the blood samples produced a spatially uniform absorbed dose as determined from Monte Carlo N-Particle version 6 simulations. The major part (71%) of the total absorbed dose to blood was determined to be from the 14 N(n,p) 14 C reaction and the remainder from the 1 H(n,γ) 2 H reaction. Previous radiobiological experiments at Canadian Nuclear Laboratories involving thermal neutron irradiation of blood yielded a relative biological effectiveness of 26 ± 7. Using the Particle and Heavy Ion Transport Code System, a similar value of ∼19 for the quality factor of thermal neutrons initiating the 14 N(n,p) 14 C reaction in soft tissue was determined by microdosimetric simulations. This calculated quality factor is of similar high value to the experimentally-derived relative biological effectiveness, and indicates the potential of thermal neutrons to induce deleterious health effects in superficial organs such as cataracts of the eye lens.

Comparing stochastic proton interactions simulated using TOPAS-nBio to experimental data from fluorescent nuclear track detectors

NASA Astrophysics Data System (ADS)

Underwood, T. S. A.; Sung, W.; McFadden, C. H.; McMahon, S. J.; Hall, D. C.; McNamara, A. L.; Paganetti, H.; Sawakuchi, G. O.; Schuemann, J.

2017-04-01

Whilst Monte Carlo (MC) simulations of proton energy deposition have been well-validated at the macroscopic level, their microscopic validation remains lacking. Equally, no gold-standard yet exists for experimental metrology of individual proton tracks. In this work we compare the distributions of stochastic proton interactions simulated using the TOPAS-nBio MC platform against confocal microscope data for Al2O3:C,Mg fluorescent nuclear track detectors (FNTDs). We irradiated 8× 4× 0.5 mm3 FNTD chips inside a water phantom, positioned at seven positions along a pristine proton Bragg peak with a range in water of 12 cm. MC simulations were implemented in two stages: (1) using TOPAS to model the beam properties within a water phantom and (2) using TOPAS-nBio with Geant4-DNA physics to score particle interactions through a water surrogate of Al2O3:C,Mg. The measured median track integrated brightness (IB) was observed to be strongly correlated to both (i) voxelized track-averaged linear energy transfer (LET) and (ii) frequency mean microdosimetric lineal energy, \\overline{{{y}F}} , both simulated in pure water. Histograms of FNTD track IB were compared against TOPAS-nBio histograms of the number of terminal electrons per proton, scored in water with mass-density scaled to mimic Al2O3:C,Mg. Trends between exposure depths observed in TOPAS-nBio simulations were experimentally replicated in the study of FNTD track IB. Our results represent an important first step towards the experimental validation of MC simulations on the sub-cellular scale and suggest that FNTDs can enable experimental study of the microdosimetric properties of individual proton tracks.

Comparing stochastic proton interactions simulated using TOPAS-nBio to experimental data from fluorescent nuclear track detectors.

PubMed

Underwood, T S A; Sung, W; McFadden, C H; McMahon, S J; Hall, D C; McNamara, A L; Paganetti, H; Sawakuchi, G O; Schuemann, J

2017-04-21

Whilst Monte Carlo (MC) simulations of proton energy deposition have been well-validated at the macroscopic level, their microscopic validation remains lacking. Equally, no gold-standard yet exists for experimental metrology of individual proton tracks. In this work we compare the distributions of stochastic proton interactions simulated using the TOPAS-nBio MC platform against confocal microscope data for Al 2 O 3 :C,Mg fluorescent nuclear track detectors (FNTDs). We irradiated [Formula: see text] mm 3 FNTD chips inside a water phantom, positioned at seven positions along a pristine proton Bragg peak with a range in water of 12 cm. MC simulations were implemented in two stages: (1) using TOPAS to model the beam properties within a water phantom and (2) using TOPAS-nBio with Geant4-DNA physics to score particle interactions through a water surrogate of Al 2 O 3 :C,Mg. The measured median track integrated brightness (IB) was observed to be strongly correlated to both (i) voxelized track-averaged linear energy transfer (LET) and (ii) frequency mean microdosimetric lineal energy, [Formula: see text], both simulated in pure water. Histograms of FNTD track IB were compared against TOPAS-nBio histograms of the number of terminal electrons per proton, scored in water with mass-density scaled to mimic Al 2 O 3 :C,Mg. Trends between exposure depths observed in TOPAS-nBio simulations were experimentally replicated in the study of FNTD track IB. Our results represent an important first step towards the experimental validation of MC simulations on the sub-cellular scale and suggest that FNTDs can enable experimental study of the microdosimetric properties of individual proton tracks.

Relation between lineal energy distribution and relative biological effectiveness for photon beams according to the microdosimetric kinetic model.

PubMed

Okamoto, Hiroyuki; Kanai, Tatsuaki; Kase, Yuki; Matsumoto, Yoshitaka; Furusawa, Yoshiya; Fujita, Yukio; Saitoh, Hidetoshi; Itami, Jun; Kohno, Toshiyuki

2011-01-01

Our cell survival data showed the obvious dependence of RBE on photon energy: The RBE value for 200 kV X-rays was approximately 10% greater than those for mega-voltage photon beams. In radiation therapy using mega-voltage photon beams, the photon energy distribution outside the field is different with that in the radiation field because of a large number of low energy scattering photons. Hence, the RBE values outside the field become greater. To evaluate the increase in RBE, the method of deriving the RBE using the Microdosimetric Kinetic model (MK model) was proposed in this study. The MK model has two kinds of the parameters, tissue-specific parameters and the dose-mean lineal energy derived from the lineal energy distributions measured with a Tissue-Equivalent Proportional Counter (TEPC). The lineal energy distributions with the same geometries of the cell irradiations for 200 kV X-rays, (60)Co γ-rays, and 6 MV X-rays were obtained with the TEPC and Monte Carlo code GEANT4. The measured lineal energy distribution for 200 kV X-rays was quite different from those for mega-voltage photon beams. The dose-mean lineal energy of 200 kV X-rays showed the greatest value, 4.51 keV/µm, comparing with 2.34 and 2.36 keV/µm for (60)Co γ-rays and 6 MV X-rays, respectively. By using the results of the TEPC and cell irradiations, the tissue-specific parameters in the MK model were determined. As a result, the RBE of the photon beams (y(D): 2~5 keV/µm) in arbitrary conditions can be derived by the measurements only or the calculations only of the dose-mean lineal energy.

Laboratory Study on Disconnection Events in Comets

NASA Astrophysics Data System (ADS)

Li, Yan-Fei; Li, Yu-Tong; Wang, Wei-Min; Yuan, Da-Wei; et al.

2018-01-01

When comets interacting with solar wind, straight and narrow plasma tails will be often formed. The most remarkable phenomenon of the plasma tails is the disconnection event, in which a plasma tail is uprooted from the comet's head and moves away from the comet. In this paper, the interaction process between a comet and solar wind is simulated by using a laser-driven plasma cloud to hit a cylinder obstacle. A disconnected plasma tail is observed behind the obstacle by optical shadowgraphy and interferometry. Our particle-in-cell simulations show that the diference in thermal velocity between ions and electrons induces an electrostatic field behind the obstacle. This field can lead to the convergence of ions to the central region, resulting in a disconnected plasma tail. This electrostatic field-induced model may be a possible explanation for the disconnection events of cometary tails.

Conditions for positive and negative recencies in running memory-span recognition.

PubMed

Ruiz, R Marcos; Elosúa, M Rosa

2013-10-01

A positive recency effect in a running-span recognition procedure was obtained in Experiment 1 for hits and for intratrial false alarms. In running recall procedures, recency does not fit well with an active updating hypothesis. In Experiment 2, in which the beginning of the target set was marked with a cue upon presentation, the recency effects disappeared. In Experiments 3 and 4 participants were forced to maintain 2 items in memory until the last one was presented for recognition. These three items were the target set. When the last item presentation was uncertain-because of the variable length list-an unexpected negative recency effect appeared. An explanation for this change from positive to negative recency is offered based on the sharing of attentional resources put forward by others for similar procedures. © 2013.

Did Jan van Eyck build the first photocopier in 1432?

NASA Astrophysics Data System (ADS)

Stork, David G.

2003-12-01

Recently it has been claimed that some early Renaissance painters used concave mirrors to project real inverted images onto their supports (paper, canvas, oak panel, ...) which they then traced or painted over, and that this was an important source of the increase in realism in European painting around 1420. Key exhibits adduced as evidence in support of this bold theory are a pair of portraits by Jan van Eyck of Cardinal Niccolo Albergati(&?) - a silverpoint study of 1431 and a larger oil of 1432. The contours in these two works bear striking resemblance in form (after being appropriately scaled) and at least one distinctive "relative shift" - evidence that has led proponents of the projection theory to claim that the oil was copied by means of an epidiascope or primitive opaque projector, the shift due to an accidental "bump" during the copying process. We find several difficulties with this optical explanation: there are at least two relative shifts (one horizontal and one vertical), the latter being somewhat unlikely given the putative projection equipment and setup; these shifts are in the ratio of distances of nearly 1:2, a ratio that has no natural role in the projection explanation; any accidental "bump" would surely have been noticed by van Eyck, and if so desired, corrected by him; recent analysis shows physical evidence (tiny pinpricks presumably from mechanical compass) consistent with mechanical transfer that has no role in the optical explanation; and several other points. The fidelity of the copy as well as the direction and relative magnitudes of these shifts are, however, consistent with the use of a familiar grid construction and with mechanical transfer using drawing compass and ruler or Reductionszirkel. Further, there are prominent vertical Bruchkanten (fold or fraction) lines on the grounded paper in the silverpoint study whose orientation and separation have no natural role in an optical theory, but have a plausible role in other explanations. Our rebuttal to the projection theory for these works is supposed by considertaion of hte lack of documentary evidence from both artists and scientists, of surviving optical devices, and of the artistic goals and established painting praxis in the early Renaissance.

Can Sex Differences in Science Be Tied to the Long Reach of Prenatal Hormones? Brain Organization Theory, Digit Ratio (2D/4D), and Sex Differences in Preferences and Cognition.

PubMed

Valla, Jeffrey; Ceci, Stephen J

2011-03-01

Brain organization theory posits a cascade of physiological and behavioral changes initiated and shaped by prenatal hormones. Recently, this theory has been associated with outcomes including gendered toy preference, 2D/4D digit ratio, personality characteristics, sexual orientation, and cognitive profile (spatial, verbal, and mathematical abilities). We examine the evidence for this claim, focusing on 2D/4D and its putative role as a biomarker for organizational features that influence cognitive abilities/interests predisposing males toward mathematically and spatially intensive careers. Although massive support exists for early brain organization theory overall, there are myriad inconsistencies, alternative explanations, and outright contradictions that must be addressed while still taking the entire theory into account. Like a fractal within the larger theory, the 2D/4D hypothesis mirrors this overall support on a smaller scale while likewise suffering from inconsistencies (positive, negative, and sex-dependent correlations), alternative explanations (2D/4D related to spatial preferences rather than abilities per se), and contradictions (feminine 2D/4D in men associated with higher spatial ability). Using the debate over brain organization theory as the theoretical stage, we focus on 2D/4D evidence as an increasingly important player on this stage, a demonstrative case in point of the evidential complexities of the broader debate, and an increasingly important topic in its own right.

[Does co-operation research provide approaches to explain the changes in the German hospital market?].

PubMed

Raible, C; Leidl, R

2004-11-01

The German hospital market faces an extensive process of consolidation. In this change hospitals consider cooperation as one possibility to improve competitiveness. To investigate explanations of changes in the German hospital market by theoretical approaches of cooperation research. The aims and mechanism of the theories, their relevance in terms of contents and their potential for empirical tests were used as criteria to assess the approaches, with current and future trends in the German hospital market providing the framework. Based on literature review, six theoretical approaches were investigated: industrial organization, transaction cost theory, game theory, resource dependency, institutional theory, and co-operative investment and finance theory. In addition, the data needed to empirically test the theories were specified. As a general problem, some of the theoretical approaches set a perfect market as a precondition. This precondition is not met by the heavily regulated German hospital market. Given the current regulations and the assessment criteria, industrial organization as well as resource-dependency and institutional theory approaches showed the highest potential to explain various aspects of the changes in the hospital market. So far, none of the approaches investigated provides a comprehensive and empirically tested explanation of the changes in the German hospital market. However, some of the approaches provide a theoretical background for part of the changes. As this dynamic market is economically of high significance, there is a need for further development and empirical testing of relevant theoretical approaches.

Wildland recreation in the rural South: an examination of marginality and ethnicity theory

Treesearch

Cassandra Y. Johnson; J. Michael Bowker; Donald B.K. English; Dreamal Worthen

1998-01-01

The ethnicity and marginality explanations of minority recreation participation provide the conceptual basis for the authors’ inquiry. These theories are examined for a sample of rural African-Americans and whites. Using logistic regression, the researchers test for black and while differences in: 1) visitation to wildland areas in general; 2) visitation to national...

Cultural Influences on Intertemporal Reasoning

DTIC Science & Technology

2011-11-30

Wiley & Sons. Access at: http://ssrn.com/abstract=1750266. ABSTRACT Elements of economic theory are examined to understand the Euro-American cultural... theory might be understood or misunderstood in other cultures, with the goal of facilitating inter-cultural dialog. The framework is constructed...past, and the tendency of Arab culture to integrate events into an associative gestalt as a basis for understanding and explanation. The results

Teacher Personality: A Review of Psychological Research and Guidelines for a More Comprehensive Theory in Educational Psychology

ERIC Educational Resources Information Center

Göncz, Lajos

2017-01-01

The current review aims to demonstrate that findings from personality theories can help educational psychology craft a more thorough explanation of the role of teacher personality in the educational process. This topic seemed to have been inadvertently omitted. The following five groups of studies in psychology and related fields (classified based…

Effect of experience, expectation and resource availability on perceptions of crowding among trout anglers in Pennsylvania

Treesearch

Craig A. Miller

1995-01-01

Crowding research has suggested expectancy theory as one explanation to perceptions of crowding expressed by participants in outdoor recreation activities. Expectancy theory states that an individual enters into an activity with a preconceived set of expectations for the outcome of the experience. In this study, anglers fishing on the opening day of Pennsylvania's...

Applications of the Theory of Work Adjustment to Rehabilitation and Counseling. Minnesota Studies in Vocational Rehabilitation: XXX.

ERIC Educational Resources Information Center

Lofquist, Lloyd H.; Dawis, Rene V.

This is one of a series of 30 monographs documenting the progress and accomplishments of the Minnesota Work Adjustment Project. Presented in this, the final report, is an overview of the project as well as detailed explanations of outcomes and activities. The conceptualized Work Adjustment Theory is the foremost accomplishment of the research…

How to Do Things with Mouse Clicks: Applying Austin's Speech Act Theory to Explain Learning in Virtual Worlds

ERIC Educational Resources Information Center

Loke, Swee-Kin; Golding, Clinton

2016-01-01

This article addresses learning in desktop virtual worlds where students role play for professional education. When students role play in such virtual worlds, they can learn some knowledge and skills that are useful in the physical world. However, existing learning theories do not provide a plausible explanation of how performing non-verbal…

Exploring the Intentions and Practices of Principals Regarding Inclusive Education: An Application of the Theory of Planned Behaviour

ERIC Educational Resources Information Center

Yan, Zi; Sin, Kuen-fung

2015-01-01

This study aimed at providing explanation and prediction of principals' inclusive education intentions and practices under the framework of the Theory of Planned Behaviour (TPB). A sample of 209 principals from Hong Kong schools was surveyed using five scales that were developed to assess the five components of TPB: attitude, subjective norm,…

Application of simplified Complexity Theory concepts for healthcare social systems to explain the implementation of evidence into practice.

PubMed

Chandler, Jacqueline; Rycroft-Malone, Jo; Hawkes, Claire; Noyes, Jane

2016-02-01

To examine the application of core concepts from Complexity Theory to explain the findings from a process evaluation undertaken in a trial evaluating implementation strategies for recommendations about reducing surgical fasting times. The proliferation of evidence-based guidance requires a greater focus on its implementation. Theory is required to explain the complex processes across the multiple healthcare organizational levels. This social healthcare context involves the interaction between professionals, patients and the organizational systems in care delivery. Complexity Theory may provide an explanatory framework to explain the complexities inherent in implementation in social healthcare contexts. A secondary thematic analysis of qualitative process evaluation data informed by Complexity Theory. Seminal texts applying Complexity Theory to the social context were annotated, key concepts extracted and core Complexity Theory concepts identified. These core concepts were applied as a theoretical lens to provide an explanation of themes from a process evaluation of a trial evaluating the implementation of strategies to reduce surgical fasting times. Sampled substantive texts provided a representative spread of theoretical development and application of Complexity Theory from late 1990's-2013 in social science, healthcare, management and philosophy. Five Complexity Theory core concepts extracted were 'self-organization', 'interaction', 'emergence', 'system history' and 'temporality'. Application of these concepts suggests routine surgical fasting practice is habituated in the social healthcare system and therefore it cannot easily be reversed. A reduction to fasting times requires an incentivised new approach to emerge in the surgical system's priority of completing the operating list. The application of Complexity Theory provides a useful explanation for resistance to change fasting practice. Its utility in implementation research warrants further attention and evaluation. © 2015 John Wiley & Sons Ltd.

Perceptions of Speaking Ability: An Explanation for Stage Fright.

ERIC Educational Resources Information Center

Ayres, Joe

1986-01-01

Argues that stage fright is a function of the speaker's perception that ability falls short of audience expectation. Discusses the implications of this theory for future investigations and interventions. (MS)

George C. Marshall Strategic Leadership Competencies: Lessons for Today’s Strategic Leaders

DTIC Science & Technology

2010-02-25

His espoused statements hit home with the average American who might not have heard of “ Maslows ’ hierarchy of needs ” theory, but could truly...Commission on Higher Education of the Middle State Association of Colleges and Schools, 3624 Market Street, Philadelphia, PA 19104, (215) 662-5606...the data needed , and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of

The Future Role of the Combined Action Program

DTIC Science & Technology

1991-05-06

control predominates the VC can gain resources by means of covert purchase or hit-and-run raids if not by direct taxation . 36 Similar to the personnel...It may require changing accepted practises that are hundreds of years old. Nevertheless, change is imperative if CAP is to be successful. This is...8217Communist Party of the Philippines: Theory and Practise of United Front.* Masters Thesis, United States Army Command and General Staff College, Ft

Antigen Potency and Maximal Efficacy Reveal a Mechanism of Efficient T Cell Activation

PubMed Central

Wheeler, Richard J.; Zhang, Hao; Cordoba, Shaun-Paul; Peng, Yan-Chun; Chen, Ji-Li; Cerundolo, Vincenzo; Dong, Tao; Coombs, Daniel; van der Merwe, P. Anton

2014-01-01

T cell activation, a critical event in adaptive immune responses, follows productive interactions between T cell receptors (TCRs) and antigens, in the form of peptide-bound major histocompatibility complexes (pMHCs) on the surfaces of antigen-presenting-cells. Upon activation, T cells can lyse infected cells, secrete cytokines, such as interferon-γ (IFN-γ), and perform other effector functions with various efficiencies that directly depend on the binding parameters of the TCR-pMHC complex. The mechanism that relates binding parameters to the efficiency of activation of the T cell remains controversial; some studies suggest that the dissociation constant (KD) determines the response (the “affinity model”), whereas others suggest that the off-rate (koff) is critical (the “productive hit rate model”). Here, we used mathematical modeling to show that antigen potency, as determined by the EC50, the functional correlate that is used to support KD-based models, could not be used to discriminate between the affinity and productive hit rate models. Our theoretical work showed that both models predicted a correlation between antigen potency and KD, but only the productive hit rate model predicted a correlation between maximal efficacy (Emax) and koff. We confirmed the predictions made by the productive hit rate model in experiments with cytotoxic T cell clones and a panel of pMHC variants. Therefore, we suggest that the activity of an antigen is determined by both its potency and maximal efficacy. We discuss the implications of our findings to the practical evaluation of T cell activation, for example in adoptive immunotherapies, and relate our work to the pharmacological theory of dose-response. PMID:21653229

Historical development of the distinction between bio- and abiogenesis

NASA Astrophysics Data System (ADS)

Sheldon, Robert B.

2005-09-01

Early greek philosophers laid the philosophical foundations of the distinction between bio and abiogenesis, when they debated organic and non-organic explanations for natural phenomena. Plato and Aristotle gave organic, or purpose-driven explanations for physical phenomena, whereas the materialist school of Democritus and Epicurus gave non-organic, or materialist explanations. These competing schools have alternated in popularity through history, with the present era dominated by epicurean schools of thought. Present controversies concerning evidence for exobiology and biogenesis have many aspects which reflect this millennial debate. Therefore this paper traces a selected history of this debate with some modern, 20th century developments due to quantum mechanics. It finishes with an application of quantum information theory to several exobiology debates.

Feudalism and the French Revolution.

ERIC Educational Resources Information Center

Kaiser, Thomas E.

1979-01-01

Reviews and questions the traditional established interpretation that the French Revolution was about feudalism. Concludes that revisionist historians have cast doubt upon the orthodox theory but that they have not supplied an alternative explanation. (Author/DB)

A demographic-economic explanation of political stability: Mauritius as a microcosm.

PubMed

Lempert, D

1987-06-01

"This paper examines current models of economic and political development--social modernization theory, political and economic characteristics of stable regimes, and cross country analysis of political stability--and tests them on the Indian Ocean Island of Mauritius. The analysis continues with a causal explanation for political stability in Mauritius' recent history, derived from an examination of economic policies and demographic patterns. Political change in Mauritius over the past sixty years seems to be explained best by a model for political stability which integrates specific economic and demographic factors. The model, applicable to development in other third world nations, revises Malthus' conclusion that population and economic conditions move in an oscillatory relationship and replaces it with a more comprehensive theory, suggesting that political stability is a function of both economic development and a repeating cyclical relationship between economics and population." excerpt

Dynamical minimalism: why less is more in psychology.

PubMed

Nowak, Andrzej

2004-01-01

The principle of parsimony, embraced in all areas of science, states that simple explanations are preferable to complex explanations in theory construction. Parsimony, however, can necessitate a trade-off with depth and richness in understanding. The approach of dynamical minimalism avoids this trade-off. The goal of this approach is to identify the simplest mechanisms and fewest variables capable of producing the phenomenon in question. A dynamical model in which change is produced by simple rules repetitively interacting with each other can exhibit unexpected and complex properties. It is thus possible to explain complex psychological and social phenomena with very simple models if these models are dynamic. In dynamical minimalist theories, then, the principle of parsimony can be followed without sacrificing depth in understanding. Computer simulations have proven especially useful for investigating the emergent properties of simple models.

Differentiation without distancing. explaining bi-polarization of opinions without negative influence.

PubMed

Mäs, Michael; Flache, Andreas

2013-01-01

Explanations of opinion bi-polarization hinge on the assumption of negative influence, individuals' striving to amplify differences to disliked others. However, empirical evidence for negative influence is inconclusive, which motivated us to search for an alternative explanation. Here, we demonstrate that bi-polarization can be explained without negative influence, drawing on theories that emphasize the communication of arguments as central mechanism of influence. Due to homophily, actors interact mainly with others whose arguments will intensify existing tendencies for or against the issue at stake. We develop an agent-based model of this theory and compare its implications to those of existing social-influence models, deriving testable hypotheses about the conditions of bi-polarization. Hypotheses were tested with a group-discussion experiment (N = 96). Results demonstrate that argument exchange can entail bi-polarization even when there is no negative influence.

Ethical theory, "common morality," and professional obligations.

PubMed

Alexandra, Andrew; Miller, Seumas

2009-01-01

We have two aims in this paper. The first is negative: to demonstrate the problems in Bernard Gert's account of common morality, in particular as it applies to professional morality. The second is positive: to suggest a more satisfactory explanation of the moral basis of professional role morality, albeit one that is broadly consistent with Gert's notion of common morality, but corrects and supplements Gert's theory. The paper is in three sections. In the first, we sketch the main features of Gert's account of common morality in general. In the second, we outline Gert's explanation of the source of professional moral rules and demonstrate its inadequacy. In the third section, we provide an account of our own collectivist needs-based view of the source of the role-moral obligations of many professional roles, including those of health care professionals.

Gender role orientation and anxiety symptoms among African american adolescents.

PubMed

Palapattu, Anuradha G; Kingery, Julie Newman; Ginsburg, Golda S

2006-06-01

The present study evaluated gender role theory as an explanation for the observed gender differences in anxiety symptoms among adolescents. Specifically, the relation between gender, gender role orientation (i.e., masculinity and femininity), self-esteem, and anxiety symptoms was examined in a community sample of 114 African Americans aged 14 to 19 (mean age 15.77; 57 girls). Results revealed that masculinity was negatively associated with anxiety symptoms whereas femininity was positively associated with anxiety symptoms. Gender role orientation accounted for unique variance in anxiety scores above biological gender and self-esteem, and self-esteem moderated the relation between femininity (but not masculinity) and overall anxiety symptoms. Consistent with research on children and Caucasians, findings supported gender role theory as a partial explanation for the observed gender disparity in anxiety symptoms among African American adolescents.

The Triandis model for the study of health and illness behavior: a social behavior theory with sensitivity to diversity.

PubMed

Facione, N C

1993-03-01

The Triandis model of social behavior offers exceptional promise to nurse researchers whose goal is to achieve cultural sensitivity in their research investigations. The model includes six components: consequential beliefs, affect, social influences, previous behavioral habits, physiologic arousal, and facilitating environmental resources. A directed methodology to include culture-relevant items in the measurement of each of these model components allows researchers to capture the diverse explanations of health and illness behavior that might pertain in diverse populations. Researchers utilizing the model can achieve theory-based explanations of differences they observe by gender, race/ethnicity, social class, and sexual orientation. The Triandis model can provide studies to target variables for future intervention studies, as well as highlight areas for needed political action to equalize access to and delivery of nursing care.

Information processing and dynamics in minimally cognitive agents.

PubMed

Beer, Randall D; Williams, Paul L

2015-01-01

There has been considerable debate in the literature about the relative merits of information processing versus dynamical approaches to understanding cognitive processes. In this article, we explore the relationship between these two styles of explanation using a model agent evolved to solve a relational categorization task. Specifically, we separately analyze the operation of this agent using the mathematical tools of information theory and dynamical systems theory. Information-theoretic analysis reveals how task-relevant information flows through the system to be combined into a categorization decision. Dynamical analysis reveals the key geometrical and temporal interrelationships underlying the categorization decision. Finally, we propose a framework for directly relating these two different styles of explanation and discuss the possible implications of our analysis for some of the ongoing debates in cognitive science. Copyright © 2014 Cognitive Science Society, Inc.

Limitations of Western Medicine and Models of Integration Between Medical Systems.

PubMed

Attena, Francesco

2016-05-01

This article analyzes two major limitations of Western medicine: maturity and incompleteness. From this viewpoint, Western medicine is considered an incomplete system for the explanation of living matter. Therefore, through appropriate integration with other medical systems, in particular nonconventional approaches, its knowledge base and interpretations may be widened. This article presents possible models of integration of Western medicine with homeopathy, the latter being viewed as representative of all complementary and alternative medicine. To compare the two, a medical system was classified into three levels through which it is possible to distinguish between different medical systems: epistemological (first level), theoretical (second level), and operational (third level). These levels are based on the characterization of any medical system according to, respectively, a reference paradigm, a theory on the functioning of living matter, and clinical practice. The three levels are consistent and closely consequential in the sense that from epistemology derives theory, and from theory derives clinical practice. Within operational integration, four models were identified: contemporary, alternative, sequential, and opportunistic. Theoretical integration involves an explanation of living systems covering simultaneously the molecular and physical mechanisms of functioning living matter. Epistemological integration provides a more thorough and comprehensive explanation of the epistemic concepts of indeterminism, holism, and vitalism to complement the reductionist approach of Western medicine; concepts much discussed by Western medicine while lacking the epistemologic basis for their emplacement. Epistemologic integration could be reached with or without a true paradigm shift and, in the latter, through a model of fusion or subsumption.

42 CFR 495.344 - Approval of the State Medicaid HIT plan, the HIT PAPD and update, the HIT IAPD and update, and...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 5 2010-10-01 2010-10-01 false Approval of the State Medicaid HIT plan, the HIT... Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Requirements Specific to the Medicaid Program § 495.344 Approval of the State Medicaid HIT plan, the HIT PAPD...

MYC/BCL2/BCL6 triple hit lymphoma: a study of 40 patients with a comparison to MYC/BCL2 and MYC/BCL6 double hit lymphomas.

PubMed

Huang, Wenting; Medeiros, L Jeffrey; Lin, Pei; Wang, Wei; Tang, Guilin; Khoury, Joseph; Konoplev, Sergej; Yin, C Cameron; Xu, Jie; Oki, Yasuhiro; Li, Shaoying

2018-05-21

High-grade B-cell lymphomas with MYC, BCL2, and BCL6 rearrangements (triple hit lymphoma) are uncommon. We studied the clinicopathologic features of 40 patients with triple hit lymphoma and compared them to 157 patients with MYC/BCL2 double hit lymphoma and 13 patients with MYC/BCL6 double hit lymphoma. The triple hit lymphoma group included 25 men and 15 women with a median age of 61 years (range, 34-85). Nine patients had a history of B-cell lymphoma. Histologically, 23 (58%) cases were diffuse large B-cell lymphoma and 17 cases had features of B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma. Most cases of triple hit lymphoma were positive for CD10 (100%), BCL2 (95%), BCL6 (82%), MYC (74%), and 71% with MYC and BCL2 coexpression. P53 was overexpressed in 29% of triple hit lymphoma cases. The clinicopathological features of triple hit lymphoma patients were similar to patients with MYC/BCL2 and MYC/BCL6 double hit lymphoma, except that triple hit lymphoma cases were more often CD10 positive compared with MYC/BCL6 double hit lymphoma (p < 0.05). Induction chemotherapy used was similar for patients with triple hit lymphoma and double hit lymphoma and overall survival in triple hit lymphoma patients was 17.6 months, similar to the overall survival of patients with double hit lymphoma (p = 0.67). Patients with triple hit lymphoma showing P53 overexpression had significantly worse overall survival compared with those without P53 overexpression (p = 0.04). On the other hand, double expressor status and prior history of B-cell lymphoma did not correlate with overall survival. In conclusion, most patients with triple hit lymphoma have an aggressive clinical course and poor prognosis and these tumors have a germinal center B-cell immunophenotype, similar to patients with double hit lymphomas. P53 expression is a poor prognostic factor in patients with triple hit lymphoma.

In Vitro Cytotoxicity of Low-Dose-Rate Radioimmunotherapy by the Alpha-Emitting Radioimmunoconjugate Thorium-227-DOTA-Rituximab

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

Dahle, Jostein, E-mail: jostein.dahle@rr-research.n; Krogh, Cecilie; Melhus, Katrine B.

2009-11-01

Purpose: To determine whether the low-dose-rate alpha-particle-emitting radioimmunoconjugate {sup 227}Th-1,4,7,10-p-isothiocyanato-benzyl-tetraazacyclododecane-1,4,7, 10-tetraacetic acid (DOTA)-rituximab can be used to inactivate lymphoma cells growing as single cells and small colonies. Methods and Materials: CD20-positive lymphoma cell lines were treated with {sup 227}Th-DOTA-rituximab for 1-5 weeks. To simulate the in vivo situation with continuous but decreasing supply of radioimmunoconjugates from the blood pool, the cells were not washed after incubation with {sup 227}Th-DOTA-rituximab, but half of the medium was replaced with fresh medium, and cell concentration and cell-bound activity were determined every other day after start of incubation. A microdosimetric model was established tomore » estimate the average number of hits in the nucleus for different localizations of activity. Results: There was a specific targeted effect on cell growth of the {sup 227}Th-DOTA-rituximab treatment. Although the cells were not washed after incubation with {sup 227}Th-DOTA-rituximab, the average contribution of activity in the medium to the mean dose was only 6%, whereas the average contribution from activity on the cells' own surface was 78%. The mean dose rates after incubation with 800 Bq/mL {sup 227}Th-DOTA-rituximab varied from 0.01 to 0.03 cGy/min. The average delay in growing from 10{sup 5} to 10{sup 7} cells/mL was 15 days when the cells were treated with a mean absorbed radiation dose of 2 Gy alpha-particle radiation from {sup 227}Th-DOTA-rituximab, whereas it was 11 days when the cells were irradiated with 6 Gy of X-radiation. The relative biologic effect of the treatment was estimated to be 2.9-3.4. Conclusions: The low-dose-rate radioimmunoconjugate {sup 227}Th-DOTA-rituximab is suitable for inactivation of single lymphoma cells and small colonies of lymphoma cells.« less

The microdistribution of α-active nuclides in the human lung

NASA Astrophysics Data System (ADS)

Henshaw, D. L.; Fews, A. P.

1984-06-01

Elsewhere (refs. [4,5]) the authors have discussed new and elaborate techniques for alpha-particle autoradiography using the nuclear track detector CR-39. These techniques are at present being applied in a major study of the microdistribution of alpha-active nuclides in the human lung. Whole lungs with trachea are obtained at autopsy. Case histories representing a wide spectrum of lung burden are sought but that from the general population serves as a baseline from which all abnormal levels may be compared. The lungs are dissected, loaded against CR-39 and stored deep frozen for 3-20 months. Subsequent analysis of the autoradiograph reveals: (i) The microdistribution of activity. This includes for example the pattern of deposition around the tracheal bifurcation and across the tracheal wall for both the total activity and separately that due to 222Rn + daughter nuclei and, the distribution of single and multiple decays from single points over the storage period of the autoradiograph. The information enables the frequency of single and multiple hits to sensitive cells in the lung to be calculated. This is an important step in estimating the frequency of radiation induced mutations. (ii) The absolute abundance of alpha-active nuclides present at each site. This quantity is determined at particular locations in lung such as bifurcations in the major airways, in corresponding positions on the posterior aspect of the trachea and bronchus and parenchymal lung for each of the five lobes and in the lymph nodes. The information is obtained in normal lung over a wide span of age. This overall information may be used to study the deposition, retention and clearance patterns of different alpha-emitting elements with associated differences in size and physical and chemical nature. These studies in normal lung may provide new information on the mechanism at work in lung for the clearance of particulate matter. They may also be used to predict the behaviour of inhaled alpha-particulate matter in lung and perform microdosimetric calculations. This information may be applied to cases of occupational exposure to alpha-emitting particles such as plutonium.

Folk-Psychological Interpretation of Human vs. Humanoid Robot Behavior: Exploring the Intentional Stance toward Robots

PubMed Central

Thellman, Sam; Silvervarg, Annika; Ziemke, Tom

2017-01-01

People rely on shared folk-psychological theories when judging behavior. These theories guide people’s social interactions and therefore need to be taken into consideration in the design of robots and other autonomous systems expected to interact socially with people. It is, however, not yet clear to what degree the mechanisms that underlie people’s judgments of robot behavior overlap or differ from the case of human or animal behavior. To explore this issue, participants (N = 90) were exposed to images and verbal descriptions of eight different behaviors exhibited either by a person or a humanoid robot. Participants were asked to rate the intentionality, controllability and desirability of the behaviors, and to judge the plausibility of seven different types of explanations derived from a recently proposed psychological model of lay causal explanation of human behavior. Results indicate: substantially similar judgments of human and robot behavior, both in terms of (1a) ascriptions of intentionality/controllability/desirability and in terms of (1b) plausibility judgments of behavior explanations; (2a) high level of agreement in judgments of robot behavior – (2b) slightly lower but still largely similar to agreement over human behaviors; (3) systematic differences in judgments concerning the plausibility of goals and dispositions as explanations of human vs. humanoid behavior. Taken together, these results suggest that people’s intentional stance toward the robot was in this case very similar to their stance toward the human. PMID:29184519

On the RNG theory of turbulence

NASA Technical Reports Server (NTRS)

Lam, S. H.

1992-01-01

The Yakhot and Orszag (1986) renormalization group (RNG) theory of turbulence has generated a number of scaling law constants in reasonable quantitative agreement with experiments. The theory itself is highly mathematical, and its assumptions and approximations are not easily appreciated. The present paper reviews the RNG theory and recasts it in more conventional terms using a distinctly different viewpoint. A new formulation based on an alternative interpretation of the origin of the random force is presented, showing that the artificially introduced epsilon in the original theory is an adjustable parameter, thus offering a plausible explanation for the remarkable record of quantitative success of the so-called epsilon-expansion procedure.

Spontaneous heparin-induced thrombocytopenia (HIT) syndrome: HIT without any heparin exposure.

PubMed

Miyata, Shigeki

2016-01-01

Heparin-induced thrombocytopenia (HIT) is a pro-thrombotic side effect of heparin therapy caused by HIT antibodies with platelet-activating properties. Recent advances in understanding of spontaneous HIT syndrome, which can occur even without any heparin exposure despite its clinical and serological characteristics being similar to those of HIT, reveal the following HIT clinical features atypical for an immune-mediated disease. Heparin-naïve patients can develop IgG antibodies as early as day 4, as in a secondary immune response. Evidence for an anamnestic response upon heparin re-exposure is lacking. In addition, HIT antibodies are relatively short-lived, unlike those in a secondary immune response. Antigen immunoassays are commonly used worldwide for serological diagnosis of HIT. However, such assays do not indicate whether HIT antibodies have platelet-activating properties, leading to low diagnostic specificity for HIT. The detection of platelet-activating antibodies using a washed platelet activation assay is crucial for making a HIT diagnosis. These atypical clinical and serological features should be carefully considered while appropriately diagnosing HIT, which leads to appropriate therapy such as immediate administration of an alternative anticoagulant for preventing thromboembolic events and re-administration of heparin during surgery involving cardiopulmonary bypass when HIT antibodies are no longer detectable.

Professional physical scientists display tenacious teleological tendencies: purpose-based reasoning as a cognitive default.

PubMed

Kelemen, Deborah; Rottman, Joshua; Seston, Rebecca

2013-11-01

Teleological explanations account for objects and events by reference to a functional consequence or purpose. Although they are popular in religion, they are unpopular in science: Physical scientists in particular explicitly reject them when explaining natural phenomena. However, prior research provides reasons to suspect that this explanatory form may represent a default explanatory preference. As a strong test of this hypothesis, we explored whether physical scientists endorse teleological explanations of natural phenomena when their information-processing resources are limited. In Study 1, physical scientists from top-ranked American universities judged explanations as true or false, either at speed or without time restriction. Like undergraduates and age-matched community participants, scientists demonstrated increased acceptance of unwarranted teleological explanations under speed despite maintaining high accuracy on control items. Scientists' overall endorsement of inaccurate teleological explanation was lower than comparison groups, however. In Study 2, we explored this further and found that the teleological tendencies of professional scientists did not differ from those of humanities scholars. Thus, although extended education appears to produce an overall reduction in inaccurate teleological explanation, specialization as a scientist does not, in itself, additionally ameliorate scientifically inaccurate purpose-based theories about the natural world. A religion-consistent default cognitive bias toward teleological explanation tenaciously persists and may have subtle but profound consequences for scientific progress. PsycINFO Database Record (c) 2013 APA, all rights reserved.

The Examination of the Decline of Philosophy of Education with Institutional Theory: A Focus on the Last Three Decades

ERIC Educational Resources Information Center

Colgan, Andrew D.

2018-01-01

Many symposia and special journal issues over the last several decades have been devoted to concerns about the decline of philosophy in teacher education programs. I pursued an answer for my doctoral project and found institutional explanations are rarely invoked in the "decline literature." I have sketched here the theory and have shown…

Self-Control, Native Traditionalism, and Native American Substance Use: Testing the Cultural Invariance of a General Theory of Crime

ERIC Educational Resources Information Center

Morris, Gregory D.; Wood, Peter B.; Dunaway, R. Gregory

2006-01-01

Using a sample of White and Native American high school students, the authors provide a test of (a) self-control theory's invariance thesis and (b) native traditionalism as an explanation of Native American substance use. Self-control significantly influenced all forms of substance use when controlling for race and in race-specific analyses.…

Explanation of the anomalous secular increase of the moon orbit eccentricity by the new theory of gravitation (NTG)

NASA Astrophysics Data System (ADS)

Ziefle, Reiner Georg

2013-03-01

Present day gravitational physics experiences a huge success in obtaining better and better experimental results. In some cases, the observations do not fit with the present knowledge of established physics. Phenomena, like the increase of the Astronomical Unit by 7 m per century or the so-called anomalous secular increase of the eccentricity of the lunar orbit by about 9 × 10^-12 per year, which can neither be explained by Einstein's Theory of General Relativity, nor by the Newtonian Theory of Gravitation, can be explained by the New Theory of Gravitation

Developing perspectives on Korean nursing theory: the influences of Taoism.

PubMed

Shin, K R

2001-10-01

Nursing theory provides a systematic explanation and description of nursing phenomena. Western nursing theories have widely influenced Korean nursing. And yet, although nursing theory has universal aspects, the differences in philosophy and culture that are unique to each country need to be considered. This inquiry seeks to investigate the Korean cultural heritage, which integrates Confucianism, Buddhism, and Taoism, and how it provides a unique worldview of human beings, the universe, health, and nursing. Essential principles and therapies consistent with Taoist philosophy are also identified. This framework is proffered as the basis for establishing understanding between Korean nurses and patients.

Self-determination theory: a framework for clubhouse psychosocial rehabilitation research.

PubMed

Raeburn, Toby; Schmied, Virginia; Hungerford, Catherine; Cleary, Michelle

2015-02-01

The Clubhouse model is a widely used approach to psychosocial rehabilitation that has been a pioneer in supporting recovery-oriented programmes. Little consideration has been given however, to the theories that guide research of the recovery practices used by Clubhouses. In this paper, we provide a description of self-determination theory, including its philosophical background followed by explanation of its relevance to health care and Clubhouse contexts. We argue that self-determination theory provides a robust social constructionist theoretical framework that is well-suited to informing research related to psychosocial rehabilitation, recovery-oriented practices and the Clubhouse model.

The Complex Nature of Opening Reference Questions

ERIC Educational Resources Information Center

Eichman, Thomas Lee

1978-01-01

The purpose of this study is to review communication theory models and some of the literature from philosophy and linguistics in an attempt to supply a rational explanation for the generality of opening reference questions. (Author)

Understanding Magnetic Anomalies and Their Significance.

ERIC Educational Resources Information Center

Shea, James H.

1988-01-01

Describes a laboratory exercise testing the Vine-Matthews-Morley hypothesis of plate tectonics. Includes 14 questions with explanations using graphs and charts. Provides a historical account of the current plate tectonic and magnetic anomaly theory. (MVL)

The Helicity Injected Torus (HIT) Program

NASA Astrophysics Data System (ADS)

Jarboe, T. R.; Gu, P.; Hamp, W.; Izzo, V.; Jewell, P.; Liptac, J.; McCollam, K. J.; Nelson, B. A.; Raman, R.; Redd, A. J.; Shumlak, U.; Sieck, P. E.; Smith, R. J.; Jain, K. K.; Nagata, M.; Uyama, T.

2000-10-01

The purpose of the Helicity Injected Torus (HIT) program is to develop current drive techniques for low-aspect-ratio toroidal plasmas. The present HIT-II spherical tokamak experiment is capable of both Coaxial Helicity Injection (CHI) and transformer action current drive. The HIT-II device itself is modestly sized (major radius R = 0.3 m, minor radius a = 0.2 m, with an on-axis magnetic field of up to Bo = 0.5 T), but has demonstrated toroidal plasma currents of up to 200 kA, using either CHI or transformer drive. An overview of ongoing research on HIT-II plasmas, including recent results, will be presented. An electron-locking model has been developed for helicity injection current drive; a description of this model will be presented, as well as comparisons to experimental results from the HIT and HIT-II devices. Empirical results from both the HIT program and past spheromak research, buttressed by theoretical developments, have led to the design of the upcoming HIT-SI (Helicity Injected Torus with Steady Inductive helicity injection) device (T.R. Jarboe, Fusion Technology 36, p. 85, 1999). HIT-SI will be able to form a high-beta spheromak, a low aspect ratio RFP or a spherical tokamak using constant inductive helicity injection. The HIT-SI design and construction progress will be presented.

Assessment of the performances of AcuStar HIT and the combination with heparin-induced multiple electrode aggregometry: a retrospective study.

PubMed

Minet, V; Bailly, N; Douxfils, J; Osselaer, J C; Laloy, J; Chatelain, C; Elalamy, I; Chatelain, B; Dogné, J M; Mullier, F

2013-09-01

Early diagnosis of immune heparin-induced thrombocytopenia (HIT) is challenging. HemosIL® AcuStar HIT and heparin-induced multiple electrode aggregometry (HIMEA) were recently proposed as rapid diagnostic methods. We conducted a study to assess performances of AcuStar HIT-IgG (PF4-H) and AcuStar HIT-Ab (PF4-H). The secondary objective was to compare the performances of the combination of Acustar HIT and HIMEA with standardised clinical diagnosis. Sera of 104 suspected HIT patients were retrospectively tested with AcuStar HIT. HIMEA was performed on available sera (n=81). The clinical diagnosis was established by analysing in a standardized manner the patient's medical records. These tests were also compared with PF4-Enhanced®, LTA, and SRA in subsets of patients. Thresholds were determined using ROC curve analysis with clinical outcome as reference. Using the recommended thresholds (1.00AU), the negative predictive value (NPV) of HIT-IgG and HIT-Ab were 100.0% (95% CI: 95.9%-100.0% and 95.7%-100.0%). The positive predictive value (PPV) were 64.3% (95% CI: 35.1%-87.2.2%) and 45.0% (95% CI: 23.2%-68.6%), respectively. Using our thresholds (HIT-IgG: 2.89AU, HIT-Ab: 9.41AU), NPV of HIT-IgG and HIT-Ab were 100.0% (95% CI: 96.0%-100.0% and 96.1%-100.0%). PPV were 75.0% (95% CI: 42.7%-94.5%) and 81.8% (95% CI: 48.3%-97.7%), respectively. Of the 79 patients with a medium-high pretest probability score, 67 were negative using HIT-IgG (PF4-H) test at our thresholds. HIMEA was performed on HIT-IgG positive patients. Using this combination, only one patient on 79 was incorrectly diagnosed. Acustar HIT showed good performances to exclude the diagnosis of HIT. Combination with HIMEA improves PPV. Copyright © 2013 Elsevier Ltd. All rights reserved.

Computational rationality: linking mechanism and behavior through bounded utility maximization.

PubMed

Lewis, Richard L; Howes, Andrew; Singh, Satinder

2014-04-01

We propose a framework for including information-processing bounds in rational analyses. It is an application of bounded optimality (Russell & Subramanian, 1995) to the challenges of developing theories of mechanism and behavior. The framework is based on the idea that behaviors are generated by cognitive mechanisms that are adapted to the structure of not only the environment but also the mind and brain itself. We call the framework computational rationality to emphasize the incorporation of computational mechanism into the definition of rational action. Theories are specified as optimal program problems, defined by an adaptation environment, a bounded machine, and a utility function. Such theories yield different classes of explanation, depending on the extent to which they emphasize adaptation to bounds, and adaptation to some ecology that differs from the immediate local environment. We illustrate this variation with examples from three domains: visual attention in a linguistic task, manual response ordering, and reasoning. We explore the relation of this framework to existing "levels" approaches to explanation, and to other optimality-based modeling approaches. Copyright © 2014 Cognitive Science Society, Inc.

The Explanation of the Pauli Exclusion Principle

NASA Astrophysics Data System (ADS)

Vasiliev, Victor; Moon, Russell

2006-11-01

Using the principles of the Vortex Theory, the construction of the alpha particle, and the theory that the nucleus is constructed out of alpha particles, the explanation of the Pauli Exclusion Principle is explained. If protons and electrons are connected to each other via fourth dimensional vortices, they spin in opposite directions. Since the alpha particle possesses two protons possessing opposite spins, their electrons also possess opposite spins. With a nucleus constructed out of alpha particles, all paired electrons in shells and sub-shells will spin in opposite directions. 1. Victor Vasiliev, Russell Moon. Controversy surrounding the Experiment conducted to prove the Vortex Theory, 2006 8th Annual Meeting of the Northwest Section, May 18-20, 2006, University of Puget Sound, Tacoma, Washington, USA, Abstract C1.00009. 2. Russell Moon. To the Photon Acceleration Effect, 2006 Texas Section APS/AAPT/SPS Joint Spring Meeting, Thursday--Saturday, March 23--25, 2006; San Angelo, Texas, Abstract: POS.00008. 3. Russell Moon, Fabian Calvo, Victor Vasiliev. The Neutral Pentaquark, 2006 APS March Meeting, March 13-17, Baltimore, MD, USA, Session Q1: GENERAL POSTER SESSION, Abstract Q1.00147.

The point of E 8 in F-theory GUTs

NASA Astrophysics Data System (ADS)

Heckman, Jonathan J.; Tavanfar, Alireza; Vafa, Cumrun

2010-08-01

We show that in F-theory GUTs, a natural explanation of flavor hierarchies in the quark and lepton sector requires a single point of E 8 enhancement in the internal geometry, from which all Yukawa couplings originate. The monodromy group acting on the seven-brane configuration plays a key role in this analysis. Moreover, the E 8 structure automatically leads to the existence of the additional fields and interactions needed for minimal gauge mediated supersymmetry breaking, and almost nothing else. Surprisingly, we find that in all but one Dirac neutrino scenario the messenger fields in the gauge mediated supersymmetry breaking sector transform as vector-like pairs in the 10 oplus overline {10} of SU(5). We also classify dark matter candidates available from this enhancement point, and rule out both annihilating and decaying dark matter scenarios as explanations for the recent experiments PAMELA, ATIC and FERMI. In F-theory GUT models, a 10-100 MeV mass gravitino remains as the prime candidate for dark matter, thus suggesting an astrophysical origin for recent experimental signals.

A unified econophysics explanation for the power-law exponents of stock market activity

NASA Astrophysics Data System (ADS)

Gabaix, Xavier; Gopikrishnan, Parameswaran; Plerou, Vasiliki; Stanley, Eugene

2007-08-01

We survey a theory (first sketched in Nature in 2003, then fleshed out in the Quarterly Journal of Economics in 2006) of the economic underpinnings of the fat-tailed distributions of a number of financial variables, such as returns and trading volume. Our theory posits that they have a common origin in the strategic trading behavior of very large financial institutions in a relatively illiquid market. We show how the fat-tailed distribution of fund sizes can indeed generate extreme returns and volumes, even in the absence of fundamental news. Moreover, we are able to replicate the individually different empirical values of the power-law exponents for each distribution: 3 for returns, 3/2 for volumes, 1 for the assets under management of large investors. Large investors moderate their trades to reduce their price impact; coupled with a concave price impact function, this leads to volumes being more fat-tailed than returns but less fat-tailed than fund sizes. The trades of large institutions also offer a unified explanation for apparently disconnected empirical regularities that are otherwise a challenge for economic theory.

Heparin-induced thrombocytopenia: real-world issues.

PubMed

Linkins, Lori-Ann; Warkentin, Theodore E

2011-09-01

Heparin-induced thrombocytopenia (HIT) is a prothrombotic drug reaction caused by platelet-activating antibodies. HIT sera often activate platelets without needing heparin-such heparin-"independent" platelet activation can be associated with HIT beginning or worsening despite stopping heparin ("delayed-onset HIT"). We address important issues in HIT diagnosis and therapy, using a recent cohort of HIT patients to illustrate influences of heparin type; triggers for HIT investigation; serological features of heparin-independent platelet activation; and treatment. In our cohort of recent HIT cases ( N = 13), low-molecular-weight heparin (dalteparin) was a common causative agent ( N = 8, 62%); most patients were diagnosed after HIT-thrombosis had occurred; and danaparoid was the most frequently selected treatment. Heparin-independent platelet activation was common (7/13 [54%]) and predicted slower platelet count recovery (>1 week) among evaluable patients (5/5 vs 1/6; P = 0.015). In our experience with argatroban-treated patients, HIT-associated consumptive coagulopathy confounds anticoagulant monitoring. Our observations provide guidance on practical aspects of HIT diagnosis and management. Thieme Medical Publishers.

Neonatal Imitation: Theory, Experimental Design, and Significance for the Field of Social Cognition.

PubMed

Vincini, Stefano; Jhang, Yuna; Buder, Eugene H; Gallagher, Shaun

2017-01-01

Neonatal imitation has rich implications for neuroscience, developmental psychology, and social cognition, but there is little consensus about this phenomenon. The primary empirical question, whether or not neonatal imitation exists, is not settled. Is it possible to give a balanced evaluation of the theories and methodologies at stake so as to facilitate real progress with respect to the primary empirical question? In this paper, we address this question. We present the operational definition of differential imitation and discuss why it is important to keep it in mind. The operational definition indicates that neonatal imitation may not look like prototypical imitation and sets non-obvious requirements on what can count as evidence for imitation. We also examine the principal explanations for the extant findings and argue that two theories, the arousal hypothesis and the Association by Similarity Theory, which interprets neonatal imitation as differential induction of spontaneous behavior through similarity, offer better explanations than the others. With respect to methodology, we investigate what experimental design can best provide evidence for imitation, focusing on how differential induction may be maximized and detected. Finally, we discuss the significance of neonatal imitation for the field of social cognition. Specifically, we propose links with theories of social interaction and direct social perception. Overall, our goals are to help clarify the complex theoretical issues at stake and suggest fruitful guidelines for empirical research.

Neonatal Imitation: Theory, Experimental Design, and Significance for the Field of Social Cognition

PubMed Central

Vincini, Stefano; Jhang, Yuna; Buder, Eugene H.; Gallagher, Shaun

2017-01-01

Neonatal imitation has rich implications for neuroscience, developmental psychology, and social cognition, but there is little consensus about this phenomenon. The primary empirical question, whether or not neonatal imitation exists, is not settled. Is it possible to give a balanced evaluation of the theories and methodologies at stake so as to facilitate real progress with respect to the primary empirical question? In this paper, we address this question. We present the operational definition of differential imitation and discuss why it is important to keep it in mind. The operational definition indicates that neonatal imitation may not look like prototypical imitation and sets non-obvious requirements on what can count as evidence for imitation. We also examine the principal explanations for the extant findings and argue that two theories, the arousal hypothesis and the Association by Similarity Theory, which interprets neonatal imitation as differential induction of spontaneous behavior through similarity, offer better explanations than the others. With respect to methodology, we investigate what experimental design can best provide evidence for imitation, focusing on how differential induction may be maximized and detected. Finally, we discuss the significance of neonatal imitation for the field of social cognition. Specifically, we propose links with theories of social interaction and direct social perception. Overall, our goals are to help clarify the complex theoretical issues at stake and suggest fruitful guidelines for empirical research. PMID:28824502

Better Lucky Than Good: A Theory of Unconventional Minds and the Power of Who

DTIC Science & Technology

2009-12-01

approach. Interestingly, the premise of Nagl’s book, Learning to Eat Soup with a Knife: Counterinsurgency Lessons from Malaya and Vietnam, is that only...insurgency between Hit and Baghdadi. He had operated a rural mosque and insurgents met there routinely to plan, pray , or hide. He had abandoned his...caricature of Sheriff Buford Pusser as portrayed in the semi-biopic movie Walking Tall. Why chance spoiling his image by potentially getting his nose

Hit identification and optimization in virtual screening: practical recommendations based on a critical literature analysis.

PubMed

Zhu, Tian; Cao, Shuyi; Su, Pin-Chih; Patel, Ram; Shah, Darshan; Chokshi, Heta B; Szukala, Richard; Johnson, Michael E; Hevener, Kirk E

2013-09-12

A critical analysis of virtual screening results published between 2007 and 2011 was performed. The activity of reported hit compounds from over 400 studies was compared to their hit identification criteria. Hit rates and ligand efficiencies were calculated to assist in these analyses, and the results were compared with factors such as the size of the virtual library and the number of compounds tested. A series of promiscuity, druglike, and ADMET filters were applied to the reported hits to assess the quality of compounds reported, and a careful analysis of a subset of the studies that presented hit optimization was performed. These data allowed us to make several practical recommendations with respect to selection of compounds for experimental testing, definition of hit identification criteria, and general virtual screening hit criteria to allow for realistic hit optimization. A key recommendation is the use of size-targeted ligand efficiency values as hit identification criteria.

Psychoanalytic theory and loving God concepts: parent referencing versus self-referencing.

PubMed

Buri, J R; Mueller, R A

1993-01-01

We investigated the relationship of college students' conceptions of the wrathfulness-kindliness of God to their parents' nurturance, their parents' permissiveness, authoritarianism, and authoritativeness, and the students' own self-esteem. Although parents' nurturance, authoritarianism, and authoritativeness were related to participants' conceptions of God (thus providing some support for psychoanalytic assertions), the variable of self-esteem far outweighed all other variables in accounting for the variance in God concepts. These results suggest that self-referencing explanations better account for individuals' conceptions of God than do parent referencing (i.e., psychoanalytic) explanations.

Comments on the interaction of materials with atomic oxygen

NASA Technical Reports Server (NTRS)

Torre, Larry P.; Pippin, H. Gary

1987-01-01

An explanation of the relative resistance of various materials to attack by atomic oxygen is presented. Data from both ground based and on-orbit experiments is interpreted. The results indicate the importance of bond strengths, size and structure of pendant groups, and fluorination to the resistance of certain polymers to atomic oxygen. A theory which provides a partial explanation of the degradation of materials in low Earth orbit due to surface recombination of oxygen atoms is also included. Finally, a section commenting on mechanisms of material degradation is provided.

On the self-serving function of an academic wooden leg: test anxiety as a self-handicapping strategy.

PubMed

Smith, C W; Snyder, D R; Handelsman, M M

1982-02-01

The present study investigated the hypothesis that psychological symptoms may serve a self-protective function by providing an alternative explanation for potential failure in evaluating situations. It was hypothesized that highly test-anxious subjects would report anxiety symptoms in a pattern that reflected strategic presentation of symptoms; more specifically, it was predicted that greater reported anxiety should result when anxiety was a viable explanation for poor performance on an intelligence test and that lower reported anxiety should result when anxiety was not a viable explanation for poor performance. Analysis of state measures of self-reported anxiety supported these predictions. Further analysis indicated that when anxiety was not a viable explanation for poor test performance, high test-anxiety subjects reported reduced effort as an alternative self-protective strategy. These results are discussed in terms of traditional models of symptoms as self-protective strategies, current social psychological models of symptoms, and in reference to recent theory and research about the nature and treatment of test anxiety.

Always on My Mind? Recognition of Attractive Faces May Not Depend on Attention.

PubMed

Silva, André; Macedo, António F; Albuquerque, Pedro B; Arantes, Joana

2016-01-01

Little research has examined what happens to attention and memory as a whole when humans see someone attractive. Hence, we investigated whether attractive stimuli gather more attention and are better remembered than unattractive stimuli. Participants took part in an attention task - in which matrices containing attractive and unattractive male naturalistic photographs were presented to 54 females, and measures of eye-gaze location and fixation duration using an eye-tracker were taken - followed by a recognition task. Eye-gaze was higher for the attractive stimuli compared to unattractive stimuli. Also, attractive photographs produced more hits and false recognitions than unattractive photographs which may indicate that regardless of attention allocation, attractive photographs produce more correct but also more false recognitions. We present an evolutionary explanation for this, as attending to more attractive faces but not always remembering them accurately and differentially compared with unseen attractive faces, may help females secure mates with higher reproductive value.

INFLUENCE OF DEATH CRITERIA ON THE X-RAY SURVIVAL CURVES OF THE FUNGUS, NEUROSPORA

PubMed Central

Uber, Fred M.; Goddard, David R.

1934-01-01

1. When ascospores of Neurospora tetrasperma were irradiated with 11 kv. X-rays, the single spore cultures obtained displayed a wide variety of mutated forms. 2. Control germinations of ascospores showed uniform behavior, ranging from 92–95 per cent germination. 3. The shape of the survival curves was found to be a function of the criterion of death. The following criteria were used: germination, growth, production of mature ascospores, and the production of normal perithecia. 4. The germination survival curve exhibited a rhythmic variation with dosage. Germination is not a significant criterion of death. 5. Half-survival dosages for growth and ascospore production were approximately 30,000 and 20,000 roentgens, respectively. 6. Multiple hit-to-kill relations were found on the basis of the quantum hit theory; no accurate analysis was possible. 7. The studies indicate that ascospore death does not result from a single well defined reaction, but rather from the integrated effects of several deleterious processes initiated by the radiation. PMID:19872801

Quantum transport through 3D Dirac materials

NASA Astrophysics Data System (ADS)

Salehi, M.; Jafari, S. A.

2015-08-01

Bismuth and its alloys provide a paradigm to realize three dimensional materials whose low-energy effective theory is given by Dirac equation in 3+1 dimensions. We study the quantum transport properties of three dimensional Dirac materials within the framework of Landauer-Büttiker formalism. Charge carriers in normal metal satisfying the Schrödinger equation, can be split into four-component with appropriate matching conditions at the boundary with the three dimensional Dirac material (3DDM). We calculate the conductance and the Fano factor of an interface separating 3DDM from a normal metal, as well as the conductance through a slab of 3DDM. Under certain circumstances the 3DDM appears transparent to electrons hitting the 3DDM. We find that electrons hitting the metal-3DDM interface from metallic side can enter 3DDM in a reversed spin state as soon as their angle of incidence deviates from the direction perpendicular to interface. However the presence of a second interface completely cancels this effect.

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

Salehi, M.; Jafari, S.A., E-mail: jafari@physics.sharif.edu; Center of Excellence for Complex Systems and Condensed Matter

Bismuth and its alloys provide a paradigm to realize three dimensional materials whose low-energy effective theory is given by Dirac equation in 3+1 dimensions. We study the quantum transport properties of three dimensional Dirac materials within the framework of Landauer–Büttiker formalism. Charge carriers in normal metal satisfying the Schrödinger equation, can be split into four-component with appropriate matching conditions at the boundary with the three dimensional Dirac material (3DDM). We calculate the conductance and the Fano factor of an interface separating 3DDM from a normal metal, as well as the conductance through a slab of 3DDM. Under certain circumstances themore » 3DDM appears transparent to electrons hitting the 3DDM. We find that electrons hitting the metal-3DDM interface from metallic side can enter 3DDM in a reversed spin state as soon as their angle of incidence deviates from the direction perpendicular to interface. However the presence of a second interface completely cancels this effect.« less

Framing Prospective Elementary Teachers' Conceptions of Dissolving as a Ladder of Explanations

NASA Astrophysics Data System (ADS)

Subramaniam, Karthigeyan; Esprivalo Harrell, Pamela

2013-11-01

The paper details an exploratory qualitative study that investigated 61 prospective teachers' conceptual understanding of dissolving salt and sugar in water respectively. The study was set within a 15-week elementary science methods course that included a 5E learning cycle lesson on dissolving, the instructional context. Oversby's (Prim Sci Rev 63:6-19, 2002, Aspects of teaching secondary science, Routledge Falmer, London, 2002) ladder of explanations for the context of dissolving, current scientific explanations for dissolving and perspectives on conceptions and misconceptions provided the unified framework for the study. Concept maps, interview transcripts, written artifacts, and drawings and narratives were used as data to investigate these prospective teachers' conceptual understanding of dissolving throughout the 15-weeks of the methods course. Analysis revealed that participants' explanations of dissolving were predominantly descriptive explanations (39 %) and interpretative explanations (38 %), with lower percentage occurrences of intentional (14 %) and cause and effect (9 %) level explanations. Most of these explanations were also constructed by a set of loosely connected and reinforcing everyday concepts abstracted from common everyday experiences making them misconceptions. Implications include: (1) the need for science teacher educators to use multiple platforms to derive their prospective elementary teachers' conceptual understandings of science content; and (2) to identify and help them identify their own scientific conceptions and misconceptions and how they influence the construction of scientific/nonscientific explanations. Science teacher educators also need to emphasize the role of meaningful frameworks associated with the concept that is being introduced during the Engage phase of the 5E learning cycle. This is important because, relevant prior knowledge is associated with the knowledge of the particle theory of matter and both are part of larger knowledge system comprised of interrelated scientific concepts.

Kansas Working Papers in Linguistics.

ERIC Educational Resources Information Center

Khym, Hangyoo, Ed.; Kookiattikoon, Supath, Ed.

1997-01-01

The seven working papers on linguistic theory contained in this volume include: "Two Properties of the Intransitive Resultative Construction" (Yoichi Miyamoto); "Multiple Subject Construction in Korean: A Functional Explanation" (Youngjun Jang); "Constraints on Noun Incorporation in Korean" (Hangyoo Khym);…

The Brain Revolution.

ERIC Educational Resources Information Center

Sylwester, Robert

1998-01-01

A cognitive-science revolution, reminiscent of Dewey's Progressive Education Movement, will profoundly affect future educational policy and practice. A comprehensive brain theory will emerge out of Darwin's discoveries about natural selection as a scientific explanation for biodiversity, Einstein's theoretical reconceptualization of…

Revised theory of tachyons in general relativity

NASA Astrophysics Data System (ADS)

Schwartz, Charles

2017-08-01

A minus sign is inserted, for good reason, into the formula for the energy-momentum tensor for tachyons. This leads to remarkable theoretical consequences and a plausible explanation for the phenomenon called dark energy in the cosmos.

Addition of multiple limiting resources reduces grassland diversity

USDA-ARS?s Scientific Manuscript database

Niche dimensionality is the most general theoretical explanation for biodiversity: more niches allow for more ecological tradeoffs between species and thus greater opportunities for coexistence. Resource competition theory predicts that removing resource limitations, by increasing resource availabil...

Attractiveness bias: A cognitive explanation.

PubMed

Schein, Stevie S; Trujillo, Logan T; Langlois, Judith H

2017-01-01

According to cognitive averaging theory, preferences for attractive faces result from their similarity to facial prototypes, the categorical central tendencies of a population of faces. Prototypical faces are processed more fluently, resulting in increased positive affect in the viewer.

The Aggregate Supply Curve: Keynes and Downwardly Sticky Money Wages.

ERIC Educational Resources Information Center

Wells, Paul

1985-01-01

Keynes's explanation of both the rationale underlying downwardly sticky money wages and the consequences this phenomenon has for macroeconomic theory are reviewed. An aggregate supply curve appropriate to today's economy is then interpreted. (Author/RM)

Trends in Gender Segregation in the Choice of Science and Engineering Majors*

PubMed Central

Mann, Allison; DiPrete, Thomas A.

2013-01-01

Numerous theories have been put forward for the high and continuing levels of gender segregation in science, technology, engineering, and mathematics (STEM) fields, but research has not systematically examined the extent to which these theories for the gender gap are consistent with actual trends. Using both administrative data and four separate longitudinal studies sponsored by the U.S. Department of Education’s National Center for Education Statistics (NCES), we evaluate several prominent explanations for the persisting gender gap in STEM fields related to mathematics performance and background and general life goals, and find that none of them are empirically satisfactory. Instead, we suggest that the structure of majors and their linkages to professional training and careers may combine with gender differences in educational goals to influence the persisting gender gap in STEM fields. An analysis of gendered career aspirations, course-taking patterns, and pathways to medical and law school supports this explanation. PMID:24090849

Temporal Vulnerability and the Post-Disaster 'Window of Opportunity to Woo:' a Case Study of an African-American Floodplain Neighborhood after Hurricane Floyd in North Carolina.

PubMed

de Vries, Daniel H

2017-01-01

After major flooding associated with Hurricane Floyd (1999) in North Carolina, mitigation managers seized upon the "window of opportunity" to woo residents to accept residential buyout offers despite sizable community resistance. I present a theoretical explanation of how post-crisis periods turn into "opportunities" based on a temporal referential theory that complements alternative explanations based on temporal coincidence, panarchy, and shock-doctrine theories. Results from fieldwork conducted from 2002 to 2004 illustrate how several temporal influences compromised collective calibration of "normalcy" in local cultural models, leading to an especially heightened vulnerability to collective surprise. Four factors particularly influenced this temporal vulnerability: 1) epistemological uncertainty of floodplain dynamics due to colonization; 2) cultural practices that maintained a casual amnesia; 3) meaning attributed to stochastic timing of floods; and 4) competitive impact of referential flood baseline attractors.

Hill's Heuristics and Explanatory Coherentism in Epidemiology.

PubMed

Dammann, Olaf

2018-01-01

In this essay, I argue that Ted Poston's theory of explanatory coherentism is well-suited as a tool for causal explanation in the health sciences, particularly in epidemiology. Coherence has not only played a role in epidemiology for more than half a century as one of Hill's viewpoints, it can also provide background theory for the development of explanatory systems by integrating epidemiologic evidence with a diversity of other error-independent data. I propose that computational formalization of Hill's viewpoints in an explanatory coherentist framework would provide an excellent starting point for a formal epistemological (knowledge-theoretical) project designed to improve causal explanation in the health sciences. As an example, I briefly introduce Paul Thagard's ECHO system and offer my responses to possible objections to my proposal. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Differentiation without Distancing. Explaining Bi-Polarization of Opinions without Negative Influence

PubMed Central

Mäs, Michael; Flache, Andreas

2013-01-01

Explanations of opinion bi-polarization hinge on the assumption of negative influence, individuals’ striving to amplify differences to disliked others. However, empirical evidence for negative influence is inconclusive, which motivated us to search for an alternative explanation. Here, we demonstrate that bi-polarization can be explained without negative influence, drawing on theories that emphasize the communication of arguments as central mechanism of influence. Due to homophily, actors interact mainly with others whose arguments will intensify existing tendencies for or against the issue at stake. We develop an agent-based model of this theory and compare its implications to those of existing social-influence models, deriving testable hypotheses about the conditions of bi-polarization. Hypotheses were tested with a group-discussion experiment (N = 96). Results demonstrate that argument exchange can entail bi-polarization even when there is no negative influence. PMID:24312164

Belief-desire reasoning in the explanation of behavior: do actions speak louder than words?

PubMed

Wertz, Annie E; German, Timsin C

2007-10-01

The mechanisms underwriting our commonsense psychology, or 'theory of mind', have been extensively investigated via reasoning tasks that require participants to predict the action of agents based on information about beliefs and desires. However, relatively few studies have investigated the processes contributing to a central component of 'theory of mind' - our ability to explain the action of agents in terms of underlying beliefs and desires. In two studies, we demonstrate a novel phenomenon in adult belief-desire reasoning, capturing the folk notion that 'actions speak louder than words'. When story characters were described as searching in the wrong place for a target object, adult subjects often endorsed mental state explanations referencing a distracter object, but only when that object was approached. We discuss how this phenomenon, alongside other reasoning "errors" (e.g., hindsight bias; the curse of knowledge) can be used to illuminate the architecture of domain specific belief-desire reasoning processes.

Male reproductive strategy and decreased longevity.

PubMed

Vinogradov, A E

1998-06-01

An explanation of the inter-gender difference in longevity consistent with the 'disposable soma' theory of ageing is proposed. It is based on the concept of r-K selection as applied to the inter-gender situation. The concept predicts that the gender with a higher potential reproductive rate (males) should invest relatively less in somatic maintenance, which in its turn should result in a lower longevity according to the 'disposable soma' theory of ageing. In females, which are interpreted as K-selected organisms, the reproductive strategy strongly depends on steady, secure constitution designed for oocyte/embryo bearing and is therefore closely related to somatic maintenance, whereas in (r-selected) males it has a greater behavioural component--risky, variable, with a greater potential productive success at the expense of somatic maintenance. The higher metabolic and growth rates, a higher premature mortality and a longer period of sexual competence of males also find explanation as a complex of r-selected traits.

The impact of post-event information on study-related memories: an exploration of the roles of judgemental anchoring, specific expectations about change, and motivational influences.

PubMed

Sedlmeier, Peter; Jaeger, Sonia

2007-01-01

We explored how well common theories about the impact of post-event information on memories explain recollections that occur naturally in university students' study routines. Instead of starting from a familiar research paradigm, such as those used in hindsight-bias research, the present study used a situation common to university students, and examined how well three candidate explanations--judgemental anchoring, implicit theories of change, and motivational influences--could explain the results we obtained in a long-term memory study that included three sessions, six months apart. We found that about two thirds of the memories of study-related issues were indeed biased, and that the impact of post-event information being used as an anchor is the most plausible explanation for the results. There were also some indications that memory biases might have been due, at least in part, to motivational factors.

Health complaints and wind turbines: The efficacy of explaining the nocebo response to reduce symptom reporting.

PubMed

Crichton, Fiona; Petrie, Keith J

2015-07-01

A number of people are reporting an environmental sensitivity to sub-audible windfarm sound (infrasound), characterised by the experience of recurrent non-specific symptoms. A causal link between exposure and symptoms is not indicated by empirical evidence. Research indicates symptoms may be explained by the nocebo response, whereby health concerns and negative expectations, created from social discourse and media reports, trigger symptom reporting. The experimental aim was to test whether providing a nocebo explanation for symptoms, to individuals reporting symptomatic experiences during infrasound exposure, would ameliorate symptoms during further exposure. Sixty-six volunteers were randomly assigned to nocebo explanation or biological explanation groups. Participants were concurrently exposed to infrasound and audible windfarm sound, while reporting on current symptoms and mood, during two exposure sessions. Preceding session one, participants watched a presentation integrating media warnings about purported health risks posed by windfarm infrasound. Before session two, nocebo explanation participants viewed material outlining how nocebo responding could explain symptom reporting. Instead biological explanation participants watched material presenting pathophysiological theories for symptoms. During session one, participants reported increased symptoms and mood deterioration from baseline assessment. During session two symptom reporting and mood deterioration was maintained by biological explanation participants, while mood and symptoms reported by nocebo explanation participants returned to baseline levels. Results indicate that providing an explanation of the nocebo response, followed by exposure to infrasound, has the potential to operate as an intervention to reduce symptomatic experiences in people reporting symptoms attributed to windfarm generated infrasound. Copyright © 2015 Elsevier Inc. All rights reserved.

Proceedings of the Workshop on Models of Complex Human Learning Held in Ithaca, New York on June 27-28, 1989

DTIC Science & Technology

1989-06-01

to facilitate in-depth communication of research results in a multi-disciplinary gathering led to a decision to have long presentations and limit the...learning subfields such as computational learning theory and explanation based learning? Second, as the machine learning field increases its emphasis...Architecture, Pat Langley, University of California, Irvine .................................................... 22 A Theory of Human Plausible Reasoning

A Cluster Analysis Typology of Suicide in the United States Air Force

DTIC Science & Technology

2011-08-01

theorists such as Sigmund Freud , Edwin Shneidman and other suicidologists. Typologies: Psychoanalytic. In contrast to Durkheim’s theory and its emphasis...on societal factors, many early psychological explanations of suicide were rooted in Sigmund Freud’s psychodynamic theory. Freud wrote of two...The basic writings of Sigmund Freud (pp. 35-178). New York: Random House. Garson, G. D. (2009). Cluster analysis. Retrieved November, 1, 2009 from

What Feynman Could Not yet Use: The Generalised Hong-Ou-Mandel Experiment to Improve the QED Explanation of the Pauli Exclusion Principle

ERIC Educational Resources Information Center

Malgieri, Massimiliano; Tenni, Antonio; Onorato, Pasquale; De Ambrosis, Anna

2016-01-01

In this paper we present a reasoning line for introducing the Pauli exclusion principle in the context of an introductory course on quantum theory based on the sum over paths approach. We start from the argument originally introduced by Feynman in "QED: The Strange Theory of Light and Matter" and improve it by discussing with students…

Simulating parameters of lunar physical libration on the basis of its analytical theory

NASA Astrophysics Data System (ADS)

Petrova, N.; Zagidullin, A.; Nefediev, Yu.

2014-04-01

Results of simulating behavior of lunar physical libration parameters are presented. Some features in the speed change of impulse variables are revealed: fast periodic changes in р2 and long periodic changes in р3. A problem of searching for a dynamic explanation of this phenomenon is put. The simulation was performed on the basis of the analytical libration theory [1] in the programming environment VBA.

Developing nursing care plans.

PubMed

Ballantyne, Helen

2016-02-24

This article aims to enhance nurses' understanding of nursing care plans, reflecting on the past, present and future use of care planning. This involves consideration of the central theories of nursing and discussion of nursing models and the nursing process. An explanation is provided of how theories of nursing may be applied to care planning, in combination with clinical assessment tools, to ensure that care plans are context specific and patient centred.

Children's Theories and the Drive to Explain

NASA Astrophysics Data System (ADS)

Schwitzgebel, Eric

Debate has been growing in developmental psychology over how much the cognitive development of children is like theory change in science. Useful debate on this topic requires a clear understanding of what it would be for a child to have a theory. I argue that existing accounts of theories within philosophy of science and developmental psychology either are less precise than is ideal for the task or cannot capture everyday theorizing of the sort that children, if they theorize, must do. I then propose an account of theories that ties theories and explanation very closely together, treating theories primarily as products of a drive to explain. I clarify some of the positions people have taken regarding the theory theory of development, and I conclude by proposing that psychologists interested in the ''theory theory'' look for patterns of affect and arousal in development that would accompany the existence of a drive to explain.

Organizational theory for dissemination and implementation research.

PubMed

Birken, Sarah A; Bunger, Alicia C; Powell, Byron J; Turner, Kea; Clary, Alecia S; Klaman, Stacey L; Yu, Yan; Whitaker, Daniel J; Self, Shannon R; Rostad, Whitney L; Chatham, Jenelle R Shanley; Kirk, M Alexis; Shea, Christopher M; Haines, Emily; Weiner, Bryan J

2017-05-12

Even under optimal internal organizational conditions, implementation can be undermined by changes in organizations' external environments, such as fluctuations in funding, adjustments in contracting practices, new technology, new legislation, changes in clinical practice guidelines and recommendations, or other environmental shifts. Internal organizational conditions are increasingly reflected in implementation frameworks, but nuanced explanations of how organizations' external environments influence implementation success are lacking in implementation research. Organizational theories offer implementation researchers a host of existing, highly relevant, and heretofore largely untapped explanations of the complex interaction between organizations and their environment. In this paper, we demonstrate the utility of organizational theories for implementation research. We applied four well-known organizational theories (institutional theory, transaction cost economics, contingency theories, and resource dependency theory) to published descriptions of efforts to implement SafeCare, an evidence-based practice for preventing child abuse and neglect. Transaction cost economics theory explained how frequent, uncertain processes for contracting for SafeCare may have generated inefficiencies and thus compromised implementation among private child welfare organizations. Institutional theory explained how child welfare systems may have been motivated to implement SafeCare because doing so aligned with expectations of key stakeholders within child welfare systems' professional communities. Contingency theories explained how efforts such as interagency collaborative teams promoted SafeCare implementation by facilitating adaptation to child welfare agencies' internal and external contexts. Resource dependency theory (RDT) explained how interagency relationships, supported by contracts, memoranda of understanding, and negotiations, facilitated SafeCare implementation by balancing autonomy and dependence on funding agencies and SafeCare developers. In addition to the retrospective application of organizational theories demonstrated above, we advocate for the proactive use of organizational theories to design implementation research. For example, implementation strategies should be selected to minimize transaction costs, promote and maintain congruence between organizations' dynamic internal and external contexts over time, and simultaneously attend to organizations' financial needs while preserving their autonomy. We describe implications of applying organizational theory in implementation research for implementation strategies, the evaluation of implementation efforts, measurement, research design, theory, and practice. We also offer guidance to implementation researchers for applying organizational theory.

Symbolic interactionism in grounded theory studies: women surviving with HIV/AIDS in rural northern Thailand.

PubMed

Klunklin, Areewan; Greenwood, Jennifer

2006-01-01

Although it is generally acknowledged that symbolic interactionism and grounded theory are connected, the precise nature of their connection remains implicit and unexplained. As a result, many grounded theory studies are undertaken without an explanatory framework. This in turn results in the description rather than the explanation of data determined. In this report, the authors make explicit and explain the nature of the connections between symbolic interactionism and grounded theory research. Specifically, they make explicit the connection between Blumer's methodological principles and processes and grounded theory methodology. In addition, the authors illustrate the explanatory power of symbolic interactionism in grounded theory using data from a study of the HIV/AIDS experiences of married and widowed Thai women.

What propels sexual murderers: a proposed integrated theory of social learning and routine activities theories.

PubMed

Chan, Heng Choon Oliver; Heide, Kathleen M; Beauregard, Eric

2011-04-01

Despite the great interest in the study of sexual homicide, little is known about the processes involved in an individual's becoming motivated to sexually kill, deciding to sexually kill, and acting on that desire, intention, and opportunity. To date, no comprehensive model of sexual murdering from the offending perspective has been proposed in the criminological literature. This article incorporates the works of Akers and Cohen and Felson regarding their social learning theory and routine activities theory, respectively, to construct an integrated conceptual offending framework in sexual homicide. This integrated model produces a stronger and more comprehensive explanation of sexual murder than any single theory currently available.

[Acupuncture: an information therapy?].

PubMed

Nissel, H

1998-01-01

Even though modern medicine continues to be governed by the morphological point of view, cybernetics and systems theory are beginning to gain in importance. The concept of "Infomedicine" serves as the basis for a discussion of regulation and the information mechanisms necessary for this to occur. Some of the new insights being made in physics, such as the theory of relativity, quantum physics, and chaos theory provide many valuable explanations. Acupuncture represents a regulation and information therapy, and many parallels can be drawn between traditional Chinese medicine and the discoveries being made in today's physics.

Information performances and illative sequences: Sequential organization of explanations of chemical phase equilibrium

NASA Astrophysics Data System (ADS)

Brown, Nathaniel James Swanton

While there is consensus that conceptual change is surprisingly difficult, many competing theories of conceptual change co-exist in the literature. This dissertation argues that this discord is partly the result of an inadequate account of the unwritten rules of human social interaction that underlie the field's preferred methodology---semi-structured interviewing. To better understand the contributions of interaction during explanations, I analyze eight undergraduate general chemistry students as they attempt to explain to various people, for various reasons, why phenomena involving chemical phase equilibrium occur. Using the methods of interaction analysis, I characterize the unwritten, but systematic, rules that these participants follow as they explain. The result is a description of the contributions of interaction to explaining. Each step in each explanation is a jointly performed expression of a subject-predicate relation, an interactive accomplishment I call an information performance (in-form, for short). Unlike clauses, in-forms need not have a coherent grammatical structure. Unlike speaker turns, in-forms have the clear function of expressing information. Unlike both clauses and speaker turns, in-forms are a co-construction, jointly performed by both the primary speaker and the other interlocutor. The other interlocutor strongly affects the form and content of each explanation by giving or withholding feedback at the end of each in-form, moments I call feedback-relevant places. While in-forms are the bricks out of which the explanation is constructed, they are secured by a series of inferential links I call an illative sequence. Illative sequences are forward-searching, starting with a remembered fact or observation and following a chain of inferences in the hope it leads to the target phenomenon. The participants treat an explanation as a success if the illative sequence generates an in-form that describes the phenomenon. If the illative sequence does not, it is partly or entirely scrubbed, a new in-form is introduced as a starting point, and the illative sequence begins anew. Knowledge of these interactional contributions to the production of explanations could allow researchers to better characterize conceptual understanding, be in a stronger position to support particular theories of conceptual change over others, improve assessments of conceptual understanding, and improve interviewing practices.

Hit Identification and Optimization in Virtual Screening: Practical Recommendations Based Upon a Critical Literature Analysis

PubMed Central

Zhu, Tian; Cao, Shuyi; Su, Pin-Chih; Patel, Ram; Shah, Darshan; Chokshi, Heta B.; Szukala, Richard; Johnson, Michael E.; Hevener, Kirk E.

2013-01-01

A critical analysis of virtual screening results published between 2007 and 2011 was performed. The activity of reported hit compounds from over 400 studies was compared to their hit identification criteria. Hit rates and ligand efficiencies were calculated to assist in these analyses and the results were compared with factors such as the size of the virtual library and the number of compounds tested. A series of promiscuity, drug-like, and ADMET filters were applied to the reported hits to assess the quality of compounds reported and a careful analysis of a subset of the studies which presented hit optimization was performed. This data allowed us to make several practical recommendations with respect to selection of compounds for experimental testing, defining hit identification criteria, and general virtual screening hit criteria to allow for realistic hit optimization. A key recommendation is the use of size-targeted ligand efficiency values as hit identification criteria. PMID:23688234

Some-or-none recollection: Evidence from item and source memory.

PubMed

Onyper, Serge V; Zhang, Yaofei X; Howard, Marc W

2010-05-01

Dual-process theory hypothesizes that recognition memory depends on 2 distinguishable memory signals. Recollection reflects conscious recovery of detailed information about the learning episode. Familiarity reflects a memory signal that is not accompanied by a vivid conscious experience but nonetheless enables participants to distinguish recently experienced probe items from novel ones. This dual-process explanation of recognition memory has gained wide acceptance among cognitive neuroscientists and some cognitive psychologists. Nonetheless, its difficulty in providing a quantitatively satisfactory description of performance has precluded a consensus not only regarding the theoretical structure of recognition memory but also about how to best measure recognition accuracy. In 2 experiments we show that neither the standard formulation of dual-process signal detection (DPSD) theory nor a widely used single-process model called the unequal-variance signal-detection (UVSD) model provides a satisfactory explanation of recognition memory across different types of stimuli (words and travel scenes). In the variable-recollection dual-process (VRDP) model, recollection fails for some old probe items, as in standard formulations of DPSD, but gives rise to a continuous distribution of memory strengths when it succeeds. The VRDP can approximate both the DPSD and UVSD. In both experiments it provides a consistently superior fit across materials to the superset of the DPSD and UVSD. The VRDP offers a simple explanation of the form of conjoint item-source judgments, something neither the DPSD nor UVSD accomplishes. The success of the VRDP supports the core assumptions of dual-process theory by providing an excellent quantitative description of recognition performance across materials and response criteria.

The Helicity Injected Torus Program

NASA Astrophysics Data System (ADS)

Jarboe, T. R.; Nelson, B. A.; Jewell, P. D.; Liptac, J. E.; McCollam, K. J.; Raman, R.; Redd, A. J.; Rogers, J. A.; Sieck, P. E.; Shumlak, U.; Smith, R. J.; Nagata, M.; Uyama, T.

1999-11-01

The Helicity Injected Torus--II (HIT--II) spherical torus is capable of both Coaxial Helicity Injection (CHI) and transformer action current drive. HIT--II has a major radius R = 0.3, minor radius a = 0.2, aspect ratio A = R/a = 1.5, with an on axis magnetic field of up to Bo = 0.67 T. HIT--II provides equilibrium control, CHI flux boundary conditions, and transformer action using 28 poloidal field coils, using active flux feedback control. HIT--II has driven up to 200 kA of plasma current, using either CHI or transformer drive. An overview and recent results of the HIT--II program will be presented. The development of a locked-electron current drive model for HIT and HIT--II has led to the design of a constant inductive helicity injection method for spherical torii. This method is incorporated in the design of the Helicity Injected Torus -- Steady Inductive (HIT-- SI)(T.R. Jarboe, Fusion Technology, 36) (1), p. 85, 1999 experiment. HIT--SI can form a high-beta spheromak, a low aspect ratio RFP, or a spherical tokamak in a steady-state manner without using electrodes. The HIT--SI design and methodology will be presented.

The Development of Early Pulsation Theory, or, How Cepheids Are Like Steam Engines

NASA Astrophysics Data System (ADS)

Stanley, M.

2012-06-01

The pulsation theory of Cepheid variable stars was a major breakthrough of early twentieth-century astrophysics. At the beginning of that century, the basic physics of normal stars was very poorly understood, and variable stars were even more mysterious. Breaking with accepted explanations in terms of eclipsing binaries, Harlow Shapley and A. S. Eddington pioneered novel theories that considered Cepheids as pulsating spheres of gas. Surprisingly, the pulsation theory not only depended on novel developments in stellar physics, but the theory also drove many of those developments. In particular, models of stars in radiative balance and theories of stellar energy were heavily inspired and shaped by ideas about variable stars. Further, the success of the pulsation theory helped justify the new approaches to astrophysics being developed before World War II.

A perspectivist approach to theory construction.

PubMed

McGuire, William J

2004-01-01

A perspectivist approach is taken to the theory-construction process in psychological research. This approach assumes that all hypotheses and theories are true, as all are false, depending on the perspective from which they are viewed, and that the purpose of research is to discover which are the crucial perspectives. Perspectivism assumes also that both the a priori conceptual phase of research and the a posteriori empirical phase have both discovery and testing functions. Topics discussed include how the perspectivist approach can improve methodology training and practice (particularly as regards theory construction); what researchers accept as theoretical explanations; the nature of mediational theories; how theories can be formalized, expressed in multiple modalities and for various scaling cases; and how experimental designs can be enriched by theory-guided mediational and interactional variables.

Microdosimetric measurements of a clinical proton beam with micrometer-sized solid-state detector.

PubMed

Anderson, Sarah E; Furutani, Keith M; Tran, Linh T; Chartier, Lachlan; Petasecca, Marco; Lerch, Michael; Prokopovich, Dale A; Reinhard, Mark; Perevertaylo, Vladimir L; Rosenfeld, Anatoly B; Herman, Michael G; Beltran, Chris

2017-11-01

Microdosimetry is a vital tool for assessing the microscopic patterns of energy deposition by radiation, which ultimately govern biological effect. Solid-state, silicon-on-insulator microdosimeters offer an approach for making microdosimetric measurements with high spatial resolution (on the order of tens of micrometers). These high-resolution, solid-state microdosimeters may therefore play a useful role in characterizing proton radiotherapy fields, particularly for making highly resolved measurements within the Bragg peak region. In this work, we obtain microdosimetric measurements with a solid-state microdosimeter (MicroPlus probe) in a clinical, spot-scanning proton beam of small spot size. The MicroPlus probe had a 3D single sensitive volume on top of silicon oxide. The sensitive volume had an active cross-sectional area of 250 μm × 10 μm and thickness of 10 μm. The proton facility was a synchrotron-based, spot-scanning system with small spot size (σ ≈ 2 mm). We performed measurements with the clinical beam current (≈1 nA) and had no detected pulse pile-up. Measurements were made in a water-equivalent phantom in water-equivalent depth (WED) increments of 0.25 mm or 1.0 mm along pristine Bragg peaks of energies 71.3 MeV and 159.9 MeV, respectively. For each depth, we measured lineal energy distributions and then calculated the dose-weighted mean lineal energy, y¯D. The measurements were repeated for two field sizes: 4 × 4 cm 2 and 20 × 20 cm 2 . For both 71.3 MeV and 159.9 MeV and for both field sizes, y¯D increased with depth toward the distal edge of the Bragg peak, a result consistent with Monte Carlo calculations and measurements performed elsewhere. For the 71.3 MeV, 4 × 4 cm 2 beam (range at 80% distal falloff, R 80  = 3.99 cm), we measured y¯D=1.96±0.08 keV/μm at WED = 2 cm, and y¯D=10.6±0.32 keV/μm at WED = 3.95 cm. For the 71.3 MeV, 20 × 20 cm 2 beam, we measured y¯D=2.46±0.12 keV/μm at WED = 2.6 cm, and y¯D=11.0±0.24 keV/μm at WED = 3 cm. For the 159.9 MeV, 4 × 4 cm 2 beam (R 80  = 17.7 cm), y¯D=2.24±0.15 keV/μm at WED = 5 cm, and y¯D=8.99±0.71 keV/μm at WED = 17.6 cm. For the 159.9 MeV, 20 × 20 cm 2 beam, y¯D=2.56±0.10 keV/μm at WED = 5 cm, and y¯D=9.24±0.73 keV/μm at WED = 17.6 cm. We performed microdosimetric measurements with a novel solid-state, silicon-on-insulator microdosimeter in a clinical spot-scanning proton beam of small spot size and unmodified beam current. For all of the proton field sizes and energies considered, the measurements of y¯D were in agreement with expected trends. Furthermore, we obtained measurements with a spatial resolution of 10 μm in the beam direction. This spatial resolution greatly exceeded that possible with a conventional gaseous tissue-equivalent proportional counter and allowed us to perform a high-resolution investigation within the Bragg peak region. The MicroPlus probe is therefore suitable for applications in proton radiotherapy. © 2017 American Association of Physicists in Medicine.

Rapid exclusion of the diagnosis of immune HIT by AcuStar HIT and heparin-induced multiple electrode aggregometry.

PubMed

Minet, V; Baudar, J; Bailly, N; Douxfils, J; Laloy, J; Lessire, S; Gourdin, M; Devalet, B; Chatelain, B; Dogné, J M; Mullier, F

2014-06-01

Accurate diagnosis of heparin-induced thrombocytopenia (HIT) is essential but remains challenging. We have previously demonstrated, in a retrospective study, the usefulness of the combination of the 4Ts score, AcuStar HIT and heparin-induced multiple electrode aggregometry (HIMEA) with optimized thresholds. We aimed at exploring prospectively the performances of our optimized diagnostic algorithm on suspected HIT patients. The secondary objective is to evaluate performances of AcuStar HIT-Ab (PF4-H) in comparison with the clinical outcome. 116 inpatients with clinically suspected immune HIT were included. Our optimized diagnostic algorithm was applied to each patient. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) of the overall diagnostic strategy as well as AcuStar HIT-Ab (at manufacturer's thresholds and at our thresholds) were calculated using clinical diagnosis as the reference. Among 116 patients, 2 patients had clinically-diagnosed HIT. These 2 patients were positive on AcuStar HIT-Ab, AcuStar HIT-IgG and HIMEA. Using our optimized algorithm, all patients were correctly diagnosed. AcuStar HIT-Ab at our cut-off (>9.41 U/mL) and at manufacturer's cut-off (>1.00 U/mL) showed both a sensitivity of 100.0% and a specificity of 99.1% and 90.4%, respectively. The combination of the 4Ts score, the HemosIL® AcuStar HIT and HIMEA with optimized thresholds may be useful for the rapid and accurate exclusion of the diagnosis of immune HIT. Copyright © 2014 Elsevier Ltd. All rights reserved.

Inappropriate documentation of heparin allergy in the medical record because of misdiagnosis of heparin-induced thrombocytopenia: frequency and consequences.

PubMed

McMahon, C M; Tanhehco, Y C; Cuker, A

2017-02-01

Essentials Misdiagnosis of heparin-induced thrombocytopenia (HIT) may be associated with adverse outcomes. We conducted a study of patients with a heparin allergy in the chart due to misdiagnosis of HIT. 42% of patients with a heparin allergy due to suspected HIT were clearly HIT-negative. 68% were unnecessarily treated with an alternative anticoagulant, 66% of whom had major bleeding. Background It is recommended that heparin be added to the allergy list of patients with heparin-induced thrombocytopenia (HIT). Misdiagnosis of HIT could lead to inappropriate documentation of a heparin allergy and adverse outcomes. Objectives To determine the frequency and consequences of inappropriate documentation of a heparin allergy because of misdiagnosis of HIT. Methods We conducted a cohort study of patients with an inappropriate heparin allergy listed in the electronic medical record (EMR) because of misdiagnosis of HIT. We searched the EMR for patients with a new heparin allergy. Patients were eligible if the reason for allergy listing was suspected acute HIT and laboratory testing for HIT was performed within 60 days. Subjects were defined as 'HIT-negative' if they had a 4Ts score of ≤ 3 or negative laboratory test results. Results Of 239 subjects with a new heparin allergy documented because of concern regarding HIT, 100 (42%) met the prespecified definition of HIT-negative. Sixty-eight (68%) HIT-negative subjects unnecessarily received an alternative parenteral anticoagulant for a median duration of 10.5 days. Among these 68 patients, 45 (66%) met criteria for major bleeding. Sixty-eight (68%) of the 100 HIT-negative subjects had an inappropriate allergy to heparin documented that persisted in the EMR for > 3 years beyond the index hospitalization. Conclusions Inappropriate listing of heparin as an allergy in the EMR because of misdiagnosis of HIT is common, is associated with substantial rates of unnecessary alternative anticoagulant use and major bleeding, and tends to persist beyond the index admission. © 2016 International Society on Thrombosis and Haemostasis.

Agravity up to infinite energy

NASA Astrophysics Data System (ADS)

Salvio, Alberto; Strumia, Alessandro

2018-02-01

The self-interactions of the conformal mode of the graviton are controlled, in dimensionless gravity theories (agravity), by a coupling f_0 that is not asymptotically free. We show that, nevertheless, agravity can be a complete theory valid up to infinite energy. When f_0 grows to large values, the conformal mode of the graviton decouples from the rest of the theory and does not hit any Landau pole provided that scalars are asymptotically conformally coupled and all other couplings approach fixed points. Then agravity can flow to conformal gravity at infinite energy. We identify scenarios where the Higgs mass does not receive unnaturally large physical corrections. We also show a useful equivalence between agravity and conformal gravity plus two extra conformally coupled scalars, and we give a simpler form for the renormalization group equations of dimensionless couplings as well as of massive parameters in the presence of the most general matter sector.

Topology Explains Why Automobile Sunshades Fold Oddly

ERIC Educational Resources Information Center

Feist, Curtis; Naimi, Ramin

2009-01-01

Automobile sunshades always fold into an "odd" number of loops. The explanation why involves elementary topology (braid theory and linking number, both explained in detail here with definitions and examples), and an elementary fact from algebra about symmetric group.

The Solar System and Its Origin

ERIC Educational Resources Information Center

Dormand, J. R.

1973-01-01

Presents a brief explanation of the solar system, including planets, asteroids, satellites, comets, planetary orbits, as well as, old and recent cosmogonic theories. Indicates that man is nearer a solution to the origin of the planetary system than ever before.

College Students' Attributions of Teacher Misbehaviors

ERIC Educational Resources Information Center

Kelsey, Dawn M.; Kearney, Patricia; Plax, Timothy G.; Allen, Terre H.; Ritter, Kerry J.

2004-01-01

Grounded in attribution theory, this investigation examined explanations students provide when college teachers misbehave, and the influence of perceived teacher immediacy shaping those interpretations. Across two different samples, college students responded to questionnaires assessing perceptions of their teachers' immediacy, teacher…

77 FR 32639 - HIT Standards Committee and HIT Policy Committee; Call for Nominations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-01

... with the implementation of the Federal Health IT Strategic Plan, and in accordance with policies... DEPARTMENT OF HEALTH AND HUMAN SERVICES HIT Standards Committee and HIT Policy Committee; Call for... Health Information Technology Policy Committee (HITPC). Name of Committees: HIT Standards Committee and...

An Investigation of the Relationship Between Automated Machine Translation Evaluation Metrics and User Performance on an Information Extraction Task

DTIC Science & Technology

2007-01-01

parameter dimension between the two models). 93 were tested.3 Model 1 log( pHits 1− pHits ) = α + β1 ∗ MetricScore (6.6) The results for each of the...505.67 oTERavg .357 .13 .007 log( pHits 1− pHits ), that is, log-odds of correct task performance, of 2.79 over the intercept only model. All... pHits 1− pHits ) = −1.15− .418× I[MT=2] − .527× I[MT=3] + 1.78×METEOR+ 1.28×METEOR × I[MT=2] + 1.86×METEOR × I[MT=3] (6.7) Model 3 log( pHits 1− pHits

Review of Social and Organizational Issues in Health Information Technology.

PubMed

Kuziemsky, Craig E

2015-07-01

This paper reviews organizational and social issues (OSIs) in health information technology (HIT). A review and synthesis of the literature on OSIs in HIT was conducted. Five overarching themes with respect to OSIs in HIT were identified and discussed: scope and frameworks for defining OSIs in HIT, context matters, process immaturity and complexity, trade-offs will happen and need to be discussed openly, and means of studying OSIs in HIT. There is a wide body of literature that provides insight into OSIs in HIT, even if many of the studies are not explicitly labelled as such. The two biggest research needs are more explicit and theoretical studies of OSI in HITs and more research on integrating micro and macro perspectives of HIT use in organizations.

Identifying and Synchronizing Health Information Technology (HIT) Events from FDA Medical Device Reports.

PubMed

Kang, Hong; Wang, Frank; Zhou, Sicheng; Miao, Qi; Gong, Yang

2017-01-01

Health information technology (HIT) events, a subtype of patient safety events, pose a major threat and barrier toward a safer healthcare system. It is crucial to gain a better understanding of the nature of the errors and adverse events caused by current HIT systems. The scarcity of HIT event-exclusive databases and event reporting systems indicates the challenge of identifying the HIT events from existing resources. FDA Manufacturer and User Facility Device Experience (MAUDE) database is a potential resource for HIT events. However, the low proportion and the rapid evolvement of HIT-related events present challenges for distinguishing them from other equipment failures and hazards. We proposed a strategy to identify and synchronize HIT events from MAUDE by using a filter based on structured features and classifiers based on unstructured features. The strategy will help us develop and grow an HIT event-exclusive database, keeping pace with updates to MAUDE toward shared learning.

Multiple-hit parameter estimation in monolithic detectors.

PubMed

Hunter, William C J; Barrett, Harrison H; Lewellen, Tom K; Miyaoka, Robert S

2013-02-01

We examine a maximum-a-posteriori method for estimating the primary interaction position of gamma rays with multiple interaction sites (hits) in a monolithic detector. In assessing the performance of a multiple-hit estimator over that of a conventional one-hit estimator, we consider a few different detector and readout configurations of a 50-mm-wide square cerium-doped lutetium oxyorthosilicate block. For this study, we use simulated data from SCOUT, a Monte-Carlo tool for photon tracking and modeling scintillation- camera output. With this tool, we determine estimate bias and variance for a multiple-hit estimator and compare these with similar metrics for a one-hit maximum-likelihood estimator, which assumes full energy deposition in one hit. We also examine the effect of event filtering on these metrics; for this purpose, we use a likelihood threshold to reject signals that are not likely to have been produced under the assumed likelihood model. Depending on detector design, we observe a 1%-12% improvement of intrinsic resolution for a 1-or-2-hit estimator as compared with a 1-hit estimator. We also observe improved differentiation of photopeak events using a 1-or-2-hit estimator as compared with the 1-hit estimator; more than 6% of photopeak events that were rejected by likelihood filtering for the 1-hit estimator were accurately identified as photopeak events and positioned without loss of resolution by a 1-or-2-hit estimator; for PET, this equates to at least a 12% improvement in coincidence-detection efficiency with likelihood filtering applied.

Health information technology and dynamic capabilities.

PubMed

Leung, Ricky C

2012-01-01

Health information technology (HIT) purports to increase quality and efficiency in health care organizations. However, health care organizations are situated in constantly changing environments. They need dynamic capabilities to implement HIT effectively. This article builds on the dynamic capabilities perspective and generates propositions about implementing HIT in dynamic environments. Specifically, I identify the (1) the necessary resources and capabilities for organizations to implement HIT; (2) the organizational capabilities and benefits that can be enhanced by HIT; and (3) the similarities and differences between three distinct forms of HIT. I synthesized the literature on dynamic capabilities and HIT to identify dynamic capabilities that are associated with (1) electronic medical records, (2) telemedicine, and (3) social media. In addition, I discuss the benefits of these HITs for improving the dynamic capabilities of health care organizations. PROPOSITIONS/FINDINGS: This article generates three sets of propositions that can be tested empirically. First, I am concerned with how organizational size and human resources affect successful implementation of HIT. In addition, I argue that three technology-specific factors--hospital type, medical specialty, and socially desirable technical features--may affect the implementation of HIT. To cope with constantly changing environmental pressures, health administrators need to deploy, modify, and/or acquire organizational resources skillfully. Practitioners need to identify dynamic capabilities to support specific forms of HIT and understand how HIT enables health care organizations in turn. The concept of evolutionary fitness in the dynamic capabilities perspective may be developed to measure HIT implementation.

Fixed Wing Performance. Theory and Flight Test Techniques

DTIC Science & Technology

1977-07-01

L , J JA , iii hit I.IbS*I u Se t UX 1-4, Xl -4 TEST PROCEDURES AND TECHTNIUE,_ Pertinent Particulars a. At the time these tests are performed, the...7 , - • • . • • • • ••: • - • • -V• ,• • • • . . . REFERENCES Section XV 1. Anthropometry of Naval Aviators, 1964, NAEC-ACEL--533. 2. Cockpit...glare shlelds, etc. Htuman e~gineering persokmet are prepared to se particuiar equipments to attain quarititative data in cockpi’ anthropometry N NOT

Quantifying Human Performance of a Dynamic Military Target Detection Task: An Application of the Theory of Signal Detection.

DTIC Science & Technology

1995-06-01

applied to analyze numerous experimental tasks (Macmillan and Creelman , 1991). One of these tasks, target detection, is the subject research. In...between each associated pair of false alarm rate and hit rate z-scores is d’ for the bias level associated with the pairing (Macmillan and Creelman , 1991...unequal variance in normal distributions (Macmillan and Creelman , 1991). 61 1966). It is described in detail for the interested reader by Green and

Theoretical design of near - infrared organic compounds

NASA Astrophysics Data System (ADS)

Brymora, Katarzyna; Ducasse, Laurent; Dautel, Olivier; Lartigau-Dagron, Christine; Castet, FréDéRic

The world follows the path of digital development faster than ever before. In consequence, the Human Machine Interfaces (HMI) market is growing as well and it requires some innovations. The goal of our work is to achieve an organic Infra-Red (IR) photodetectors hitting the performance requirements for HMI applications. The quantum chemical calculations are used to guide the synthesis and technology development. In this work, in the framework of density functional theory (DFT) and time-dependent density functional theory (TD-DFT), we consider a large variety of materials exploring small donor-acceptor-donor molecules and copolymers alternating donor and acceptor monomers. We provide a structure-property relationship in view of designing new Near-Infrared (NIR) absorbing organic molecules and polymers.

Review of Session 6: Medical Physics

PubMed Central

Fukuda, Shigekazu

2014-01-01

Medical physics is very important in carbon ion radiotherapy, as it is in conventional radiotherapy using X-rays and in estimation of exposed dose in the space environment. High-energy ion beams such as carbon beams have physical characteristics such as the Bragg curve, high LET, and nuclear reactions producing fragmentations. Therefore, understanding these properties well is essential for further development of carbon radiotherapy and manned space activity. We invited, therefore, the following six presentations relevant to issues ranging from the measurement of fragmentations, lineal energy distributions using the microdosimetric approach, and neutron dose with active beam delivery of carbon-ion therapy, to the depth–dose distribution of various ions inside a human head phantom.

Evaluation of two new automated chemiluminescent assays (HemosIL® AcuStar HIT-IgG and HemosIL® AcuStar HIT-Ab) for the detection of heparin-induced antibodies in the diagnosis of heparin-induced thrombocytopenia.

PubMed

Van Hoecke, F; Devreese, K

2012-08-01

Recently, two new, fully automated quantitative chemiluminescent immunoassays, the HemosIL(®) AcuStar HIT-IgG (PF4-H), specific for IgG anti-PF4/H antibodies, and the HemosIL(®) AcuStar HIT-Ab(PF4-H), detecting IgG, IgM and IgA anti-PF4/H antibodies, were introduced into the market. In this study, their performance was compared mutually and with the Zymutest HIA IgG and HIA IgGAM ELISA. Citrated plasmas from 87 patients with clinical suspicion of heparin-induced thrombocytopenia (HIT) were analyzed with all four assays and with a functional confirmation assay. Apart from the manufacturer's cutoffs, optimalized cutoffs were evaluated as well. Sensitivities of all assays were 100%. The Acustar HIT-IgG assay showed a higher specificity compared with the HIT-Ab assay (85%vs. 73%), using the manufacturer's cutoffs. Specificities of all assays, except for the AcuStar HIT-IgG, could be significantly improved when altering the cutoff. Titers were significantly higher for the HIT-Ab assay compared with the HIT-IgG assay (P = 0.0001). This was also the case for the patients with confirmed HIT (P = 0.0495), indicating that the one cutoff (1.0 OD) for both Acustar assays, as proposed by the manufacturer, can be adapted for the AcuStar Hit-Ab assay resulting in an increased specificity. Performance characteristics of the Acustar HIT-IgG and HIT-Ab assay are comparable to the Zymutest HIA IgG and HIA IgGAM. © 2012 Blackwell Publishing Ltd.

Cerebral High-Intensity Transient Signals during Pediatric Cardiac Catheterization: A Pilot Study Using Transcranial Doppler Ultrasonography.

PubMed

LaRovere, Kerri L; Kapur, Kush; McElhinney, Doff B; Razumovsky, Alexander; Kussman, Barry D

2017-07-01

Cerebral emboli are one potential cause of acute brain injury in children with congenital heart disease (CHD) undergoing cardiac catheterization. In this pilot study using transcranial Doppler (TCD) ultrasonography, we sought to evaluate the incidence, burden, and circumstances of cerebral high-intensity transient signals (HITS), presumably representing emboli, during pediatric cardiac catheterization. Emboli monitoring of the right middle cerebral artery was performed in five children. HITS, counted offline, were defined as unidirectional signals associated with audible "chirp" and sinusoidal correlation. HITS were grouped as single, >10 HITS ("cluster"), or HITS "with curtain effect" per 3-5 cardiac cycles. Cerebral blood flow velocity (CBFV) and pulsatility index (PI) were recorded after anesthetic induction (baseline). Total HITS in the cohort was 1,697 (790 single HITS, 606 HITS within clusters, and 301 HITS within curtains). HITS in clusters and curtains comprised 53% (907/1,697) of total HITS, and occurred in 44 clusters/curtains. Events associated with clusters/curtains included left ventricular angiography (39%; 17/44), right ventricular angiography (16%; 7/44), device placement (16%; 7/44), heparin bolus (9%; 4/44), pulmonary artery angiography (9%; 4/44), venous access (5%; 2/44), right atrial angiography (2%; 1/44), arterial access (2%; 1/44), and hemodynamic measurements (2%; 1/44). No patient had clinically detectable neurologic injury. HITS are common during pediatric cardiac catheterization, and associated with procedural factors. Whether curtains/clusters are worse than single, repetitive HITS is unknown. Larger studies are needed to determine whether HITS are a marker of risk of neurologic injury from emboli during pediatric cardiac catheterization. Copyright © 2017 by the American Society of Neuroimaging.

Platelet count recovery and seroreversion in immune HIT despite continuation of heparin: further observations and literature review.

PubMed

Shih, Andrew W; Sheppard, Jo-Ann I; Warkentin, Theodore E

2017-10-05

One of the standard distinctions between type 1 (non-immune) and type 2 (immune-mediated) heparin-induced thrombocytopenia (HIT) is the transience of thrombocytopenia: type 1 HIT is viewed as early-onset and transient thrombocytopenia, with platelet count recovery despite continuing heparin administration. In contrast, type 2 HIT is viewed as later-onset (i. e., 5 days or later) thrombocytopenia in which it is generally believed that platelet count recovery will not occur unless heparin is discontinued. However, older reports of type 2 HIT sometimes did include the unexpected observation that platelet counts could recover despite continued heparin administration, although without information provided regarding changes in HIT antibody levels in association with platelet count recovery. In recent years, some reports of type 2 HIT have confirmed the observation that platelet count recovery can occur despite continuing heparin administration, with serological evidence of waning levels of HIT antibodies ("seroreversion"). We now report two additional patient cases of type 2 HIT with platelet count recovery despite ongoing therapeutic-dose (1 case) or prophylactic-dose (1 case) heparin administration, in which we demonstrate concomitant waning of HIT antibody levels. We further review the literature describing this phenomenon of HIT antibody seroreversion and platelet count recovery despite continuing heparin administration. Our observations add to the concept that HIT represents a remarkably transient immune response, including sometimes even when heparin is continued.

Novel HIT antibody detection method using Sonoclot® coagulation analyzer.

PubMed

Wanaka, Keiko; Asada, Reiko; Miyashita, Kumiko; Kaneko, Makoto; Endo, Hirokazu; Yatomi, Yutaka

2015-01-01

Since heparin-induced thrombocytopenia (HIT), caused by the generation of antibodies against platelet factor 4 (PF4)/heparin complexes (HIT antibodies), may induce serious complications due to thrombosis, a prompt diagnosis is desirable. Functional tests with platelet activation to detect HIT antibodies are useful for diagnosis of HIT, in particular (14)C-selotonin release assay (SRA). However, they are complicated and so can be performed only in limited laboratories. We tested if a blood coagulation test using Sonoclot® analyzer can serve for the detection of HIT antibodies. A murine monoclonal antibody (HIT-MoAb) against PF4/heparin complexes was used as an alternative to human HIT antibodies. To the mixture of HIT-MoAb and heparin (0.5 U/mL, final), whole blood obtained from a healthy volunteer was added, and then the activated clotting time (ACT), clot rate (CR), and area under the curve (AUC) were measured with Sonoclot® analyzer for 30minutes. The HIT-MoAb (30 to 100μg/mL, final) concentration dependently suppressed the anticoagulation activity (prolongation of ACT and decrease of CR and AUC) of heparin. The suppression of anticoagulation effect of heparin by HIT-MoAb was demonstrated by measurements using Sonoclot® analyzer. This method may provide a new tool for screening of HIT antibodies. Copyright © 2014 Elsevier Ltd. All rights reserved.

A complex adaptive systems perspective of health information technology implementation.

PubMed

Keshavjee, Karim; Kuziemsky, Craig; Vassanji, Karim; Ghany, Ahmad

2013-01-01

Implementing health information technology (HIT) is a challenge because of the complexity and multiple interactions that define HIT implementation. Much of the research on HIT implementation is descriptive in nature and has focused on distinct processes such as order entry or decision support. These studies fail to take into account the underlying complexity of the processes, people and settings that are typical of HIT implementations. Complex adaptive systems (CAS) is a promising field that could elucidate the complexity and non-linear interacting issues that are typical in HIT implementation. Initially we sought new models that would enable us to better understand the complex nature of HIT implementation, to proactively identify problem issues that could be a precursor to unintended consequences and to develop new models and new approaches to successful HIT implementations. Our investigation demonstrates that CAS does not provide prediction, but forces us to rethink our HIT implementation paradigms and question what we think we know. CAS provides new ways to conceptualize HIT implementation and suggests new approaches to increasing HIT implementation successes.

Realistic neurons can compute the operations needed by quantum probability theory and other vector symbolic architectures.

PubMed

Stewart, Terrence C; Eliasmith, Chris

2013-06-01

Quantum probability (QP) theory can be seen as a type of vector symbolic architecture (VSA): mental states are vectors storing structured information and manipulated using algebraic operations. Furthermore, the operations needed by QP match those in other VSAs. This allows existing biologically realistic neural models to be adapted to provide a mechanistic explanation of the cognitive phenomena described in the target article by Pothos & Busemeyer (P&B).

The Discourse System Project

DTIC Science & Technology

1989-11-01

9) Are you interested in dreams in art or poetry, or psychoanalysis or dreams , or what? -o- (10) U: Give me theories about dream (ie where do they... dream ? Give a multidisciplinary historical account. You might want to include theories and explanations from religion, psychology. neurosciencc, and...computer science. You paper should be approximately thirty pages. 0: May I help you? -o- (1) U: Yes, what do you know about dreams ? -0- (2) 0: Well, do you

What Are We Really Afraid Of? The Practitioner View of the Terrorist Threat in the United States

DTIC Science & Technology

2005-03-01

theories that provide explanations for the creation of almost all motivated terrorists- anomie and strain. Consider the foundations of Emile ...Durkheim’s classic theory. Durkheim called the uniformity found in a mechanical (modern) society the collective conscience. To the extent that a society...ostracism and later criminal sanctions drive these groups to desperate measures. Durkheim argued, "society cannot be formed without our being

Reply to "Comment to a paper of M. Villata on antigravity"

NASA Astrophysics Data System (ADS)

Villata, M.

2012-01-01

In this short paper we reply to the Comment by M.J.T.F. Cabbolet on Villata's theory of antigravity. The criticisms of methodological and ontological kind presented by that author come from a misinterpretation of some concepts, perhaps due to some lack of clarity or omission of details in Villata's original article. In order to clarify these points, here we provide additional explanations regarding the assumptions and results of the theory.

Cognitive components of self esteem for individuals with severe mental illness.

PubMed

Blankertz, L

2001-10-01

In a sample of 182 individuals with severe mental illness, the applicability of reflected appraisals and self-enhancement theories as explanations for global self-esteem was examined at two time points on components of stigma, mastery, overall functioning, education, and job prestige. Path analysis demonstrated that the two theories work independently; and that stigma, mastery, and overall functioning are significant, persist over time, and have an enduring effect on self-esteem.

Future-oriented emotions in the prediction of binge-drinking intention and expectation: the role of anticipated and anticipatory emotions.

PubMed

Carrera, Pilar; Caballero, Amparo; Muñoz, Dolores

2012-06-01

The Theory of Planned Behavior (TPB) offers a parsimonious explanation of purposive behavior, but in the study of healthy and risk behaviors its sufficiency may be questioned. Working with binge-drinking, a very common risk behavior in Spanish undergraduate students, we used two strategies for improving predictions from TPB: using behavioral intention (BI) and behavioral expectation (BE) as proximal antecedents of behaviors and adding as new predictors two future-oriented emotions (anticipated and anticipatory). Hierarchical regression analyses show that while anticipated emotions improved TPB explanations of BI, anticipatory emotions improved the explanations of BE. The present results show the influence of future emotions in the prediction of behavioral intention and behavioral expectation. © 2012 The Authors. Scandinavian Journal of Psychology © 2012 The Scandinavian Psychological Associations.

Not just for consumers: context effects are fundamental to decision making.

PubMed

Trueblood, Jennifer S; Brown, Scott D; Heathcote, Andrew; Busemeyer, Jerome R

2013-06-01

Context effects--preference changes that depend on the availability of other options--have attracted a great deal of attention among consumer researchers studying high-level decision tasks. In the experiments reported here, we showed that these effects also arise in simple perceptual-decision-making tasks. This finding casts doubt on explanations limited to consumer choice and high-level decisions, and it indicates that context effects may be amenable to a general explanation at the level of the basic decision process. We demonstrated for the first time that three important context effects from the preferential-choice literature--similarity, attraction, and compromise effects--all occurred within a single perceptual-decision task. Not only do our results challenge previous explanations for context effects proposed by consumer researchers, but they also challenge the choice rules assumed in theories of perceptual decision making.

Review of Social and Organizational Issues in Health Information Technology

PubMed Central

2015-01-01

Objectives This paper reviews organizational and social issues (OSIs) in health information technology (HIT). Methods A review and synthesis of the literature on OSIs in HIT was conducted. Results Five overarching themes with respect to OSIs in HIT were identified and discussed: scope and frameworks for defining OSIs in HIT, context matters, process immaturity and complexity, trade-offs will happen and need to be discussed openly, and means of studying OSIs in HIT. Conclusions There is a wide body of literature that provides insight into OSIs in HIT, even if many of the studies are not explicitly labelled as such. The two biggest research needs are more explicit and theoretical studies of OSI in HITs and more research on integrating micro and macro perspectives of HIT use in organizations. PMID:26279951

A comparison of the double hydrodistention implantation technique (HIT) and the HIT with a polyacrylate/polyalcohol copolymer (PPC) for the endoscopic treatment of primary vesicoureteral reflux.

PubMed

Akin, Melih; Erginel, Basak; Karadag, Cetin Ali; Yildiz, Abdullah; Ozçelik, Gül Sumru; Sever, Nihat; Genc, Nimetullah Mete; Dokucu, Ali Ihsan

2014-11-01

We aimed to compare the success rates of the double hydrodistention implantation technique (HIT) and the HIT with a polyacrylate/polyalcohol copolymer (PPC) for the treatment of primary vesicoureteral reflux (VUR) with a new nonbiodegradable tissue-augmenting substance (Vantris, Promedon, Cordoba, Argentina). Between January 2011 and December 2012, fifty-two children who underwent subureteric injection for primary VUR are included. The children were randomly separated into two groups, the HIT and the double HIT groups, according to the type of injection. Success was defined as no reflux on a follow-up voiding cystourethrogram (VCUG) after 6 months. The patients were evaluated according to sex, age, grade of reflux, number of injections, and injected volume, and the radiological success rates were compared. Fifty-two patients underwent an endoscopic injection for primary grade III-V VUR. The HIT group consisted of 26 patients with 33 ureters, and the double HIT group consisted of 26 patients with 35 ureters. There were no significant differences in terms of the sex, ages, VUR grades, bilaterality between the two groups. The mean injected volumes were ml 1.12 (1.02-1.22) in the HIT group and 1.24 ml (95 % CI 1.10-1.38) in the double HIT group. The reflux was resolved in 21/33 (63.6 %) ureters in the HIT group and in 30/35 (85.7 %) ureters in the double HIT group, (p < 0.05). We had only one complication. This patient in the double HIT group, developed bilateral hydronephrosis and oliguric renal failure requiring open reimplantation at the sixth month. We observed successful results double HIT method with PPC in Grade III-V reflux, but the long-term follow-up of patients is needed for hydronephrosis. As the double HIT treatment leads to a higher success rate, its use is preferable.

PSYCHOLOGICAL VERSUS SOCIOLOGICAL EXPLANATIONS OF ETHNOCENTRISM.

ERIC Educational Resources Information Center

CAMPBELL, DONALD T.; LEVINE, ROBERT A.

A COOPERATIVE CROSS-CULTURAL STUDY OF ETHNOCENTRISM IS BASED UPON DATA COLLECTED BY ANTHROPOLOGISTS IN VARIOUS GEOGRAPHICAL LOCATIONS. EACH ANTHROPOLOGIST SPENT TWO MONTHS COLLECTING DATA ON TRADITIONAL INTERGROUP RELATIONS, STEREOTYPES, AND HYPOTHETICAL CORRELATES OF RELATED SYMPTOMS OF ETHNOCENTRISM. SOCIETAL AND PSYCHOLOGICAL THEORIES ARE…

Jahn-Teller Effect: Its History and Applicability

DOE R&D Accomplishments Database

Teller, E.

1981-08-31

The interactions between Teller, Renner, Jahn and Landau which led to the formulation of the Jahn-Teller effect are discussed. The applicability of Jahn-Teller type of theory to superconductivity and the explanation proposed by the use of Goldstone particles are assessed.

Multiple-Hit Parameter Estimation in Monolithic Detectors

PubMed Central

Barrett, Harrison H.; Lewellen, Tom K.; Miyaoka, Robert S.

2014-01-01

We examine a maximum-a-posteriori method for estimating the primary interaction position of gamma rays with multiple interaction sites (hits) in a monolithic detector. In assessing the performance of a multiple-hit estimator over that of a conventional one-hit estimator, we consider a few different detector and readout configurations of a 50-mm-wide square cerium-doped lutetium oxyorthosilicate block. For this study, we use simulated data from SCOUT, a Monte-Carlo tool for photon tracking and modeling scintillation- camera output. With this tool, we determine estimate bias and variance for a multiple-hit estimator and compare these with similar metrics for a one-hit maximum-likelihood estimator, which assumes full energy deposition in one hit. We also examine the effect of event filtering on these metrics; for this purpose, we use a likelihood threshold to reject signals that are not likely to have been produced under the assumed likelihood model. Depending on detector design, we observe a 1%–12% improvement of intrinsic resolution for a 1-or-2-hit estimator as compared with a 1-hit estimator. We also observe improved differentiation of photopeak events using a 1-or-2-hit estimator as compared with the 1-hit estimator; more than 6% of photopeak events that were rejected by likelihood filtering for the 1-hit estimator were accurately identified as photopeak events and positioned without loss of resolution by a 1-or-2-hit estimator; for PET, this equates to at least a 12% improvement in coincidence-detection efficiency with likelihood filtering applied. PMID:23193231

Video head impulse test: a review of the literature.

PubMed

Alhabib, Salman F; Saliba, Issam

2017-03-01

Video head impulse test (vHIT) is a new testing which able to identify the overt and covert saccades and study the gain of vestibulo-ocular reflex (VOR) of each semicircular canal. The aim of this study is to review the clinical use of vHIT in patients with vestibular disorders in different diseases. PubMed and Cochrane databases were searched for all articles that defined vHIT, compared vHIT with another clinical test, and studied the efficacy of vHIT as diagnostic tools with vestibular disease. 37 articles about vHIT were reviewed. All articles studied the vHIT in English and French languages up to May 2015 were included in the review. Editorial articles or short comments, conference abstracts, animal studies, and language restriction were excluded from the review. Four systems were used in the literature to do the vHIT. vHIT is physiological quick test, which studied the VOR at high frequency of each semicircular canal by calculating the duration ratio between the head impulse and gaze deviation. vHIT is more sensitive than clinical head impulse test (cHIT), especially in patient with isolated covert saccades. vHIT test is diagnostic of vestibular weakness by gain reduction and the appearance of overt and covert saccades. If the vHIT is normal, then caloric test is mandatory to rule out a peripheral origin of vertigo. It is recommended to test each semicircular canal, as isolated vertical canal weakness was identified in the literature. More investigation would be required to determine the evolution of the VOR gain with the progression of the vestibular disease.

On the Theory of Evolution Versus the Concept of Evolution: Three Observations

PubMed Central

Paz-y-Miño C., Guillermo

2016-01-01

Here we address three misconceptions stated by Rice et al. in their observations of our article Paz-y-Miño and Espinosa (Evo Edu Outreach 2:655-675, 2009), published in this journal. The five authors titled their note “The Theory of Evolution is Not an Explanation for the Origin of Life.” First, we argue that it is fallacious to believe that because the formulation of the theory of evolution, as conceived in the 1800s, did not include an explanation for the origin of life, nor of the universe, the concept of evolution would not allow us to hypothesize the possible beginnings of life and its connections to the cosmos. Not only Stanley Miller's experiments of 1953 led scientists to envision a continuum from the inorganic world to the origin and diversification of life, but also Darwin's own writings of 1871. Second, to dismiss the notion of Rice et al. that evolution does not provide explanations concerning the universe or the cosmos, we identify compelling scientific discussions on the topics: Zaikowski et al. (Evo Edu Outreach 1:65–73, 2008), Krauss (Evo Edu Outreach 3:193–197, 2010), Peretó et al. (Orig Life Evol Biosph 39:395–406, 2009) and Follmann and Brownson (Naturwissenschaften 96:1265-1292, 2009). Third, although we acknowledge that the term Darwinism may not be inclusive of all new discoveries in evolution, and also that creationists and Intelligent Designers hijack the term to portray evolution as ideology, we demonstrate that there is no statistical evidence suggesting that the word Darwinism interferes with public acceptance of evolution, nor does the inclusion of the origin of life or the universe within the concept of evolution. We examine the epistemological and empirical distinction between the theory of evolution and the concept of evolution and conclude that, although the distinction is important, it should not compromise scientific logic. PMID:26949441

Are Luxury Brand Labels and “Green” Labels Costly Signals of Social Status? An Extended Replication

PubMed Central

2017-01-01

Costly signaling theory provides an explanation for why humans are willing to a pay a premium for conspicuous products such as luxury brand-labeled clothing or conspicuous environmentally friendly cars. According to the theory, the extra cost of such products is a signal of social status and wealth and leads to advantages in social interactions for the signaler. A previous study found positive evidence for the case of luxury brand labels. However, an issue of this study was that some of the experiments were not conducted in a perfectly double-blind manner. I resolved this by replicating variations of the original design in a double-blind procedure. Additionally, besides the luxury label condition, I introduced a “green” label condition. Thus, the hypothesis that signaling theory is able to explain pro-environmental behavior was tested for the first time in a natural field setting. Further, I conducted experiments in both average and below-average socioeconomic neighborhoods, where, according to signaling theory, the effects of luxury signals should be even stronger. In contrast to the original study, I did not find positive effects of the luxury brand label in any of the five experiments. Nor did I find evidence for a green-signaling effect. Moreover, in poor neighborhoods a negative tendency of the luxury label actually became evident. This suggests that a signaling theory explanation of costly labels must take into account the characteristics of the observers, e.g. their social status. PMID:28170399

Are Luxury Brand Labels and "Green" Labels Costly Signals of Social Status? An Extended Replication.

PubMed

Berger, Joël

2017-01-01

Costly signaling theory provides an explanation for why humans are willing to a pay a premium for conspicuous products such as luxury brand-labeled clothing or conspicuous environmentally friendly cars. According to the theory, the extra cost of such products is a signal of social status and wealth and leads to advantages in social interactions for the signaler. A previous study found positive evidence for the case of luxury brand labels. However, an issue of this study was that some of the experiments were not conducted in a perfectly double-blind manner. I resolved this by replicating variations of the original design in a double-blind procedure. Additionally, besides the luxury label condition, I introduced a "green" label condition. Thus, the hypothesis that signaling theory is able to explain pro-environmental behavior was tested for the first time in a natural field setting. Further, I conducted experiments in both average and below-average socioeconomic neighborhoods, where, according to signaling theory, the effects of luxury signals should be even stronger. In contrast to the original study, I did not find positive effects of the luxury brand label in any of the five experiments. Nor did I find evidence for a green-signaling effect. Moreover, in poor neighborhoods a negative tendency of the luxury label actually became evident. This suggests that a signaling theory explanation of costly labels must take into account the characteristics of the observers, e.g. their social status.

Developing Health Information Technology (HIT) Programs and HIT Curriculum: The Southern Polytechnic State University Experience

ERIC Educational Resources Information Center

Zhang, Chi; Reichgelt, Han; Rutherfoord, Rebecca H.; Wang, Andy Ju An

2014-01-01

Health Information Technology (HIT) professionals are in increasing demand as healthcare providers need help in the adoption and meaningful use of Electronic Health Record (EHR) systems while the HIT industry needs workforce skilled in HIT and EHR development. To respond to this increasing demand, the School of Computing and Software Engineering…

Forensic Evidence and Criminal Investigations: The Impact of Ballistics Information on the Investigation of Violent Crime in Nine Cities.

PubMed

King, William R; Campbell, Bradley A; Matusiak, Matthew C; Katz, Charles M

2017-07-01

We explore the impact of information from ballistics imaging hit reports on the investigation into violent crimes. Ballistics imaging hits link two crimes involving the same firearm by forensically matching tool marks on the fired bullets or cartridge cases. Interview data collected from detectives who received a hit report were used to explore the relationship between the presence of a hit report and outcomes in 65 gun-related violent crime investigations in nine U.S. police agencies. Findings indicate hit reports rarely contribute to identification, arrest, charging, or sentencing of suspects, because of delays in producing hit reports. On average, hit reports were completed 181.4 days after the focal crime. This delay forces investigations to proceed without the benefit of information from ballistics analysis. Additionally, hit reports rarely contained detailed information that was immediately useful to investigators. Instead, hit reports required additional research by the investigator to unlock useful information. © 2017 American Academy of Forensic Sciences.

Health information technology and physicians' perceptions of healthcare quality.

PubMed

Fang, Hai; Peifer, Karen L; Chen, Jie; Rizzo, John A

2011-03-01

To investigate the relationship between the use of health information technology (HIT) and physician perceptions of providing high-quality care and to determine whether this relationship has changed over time. We used 2 waves of longitudinal data from the Community Tracking Study Physician Surveys, 2000-2001 and 2004-2005. Three measures of HIT were examined: a binary variable measuring the use of at least 1 type of HIT, a continuous variable measuring the total number of HIT types, and a binary variable measuring use of all 5 HIT types related to "meaningful use" of HIT as defined by Centers for Medicare and Medicaid Services. Three multivariate models were estimated to study the effect of each HIT measure on physicians' perception of providing high-quality care. Individual fixed-effects estimation also was used to control for individual time-invariant factors. Using at least 1 type of HIT significantly enhanced physicians' perception of providing high-quality care in 2000-2001, but not in 2004-2005. The marginal effect of adding 1 extra HIT type was positive and statistically significant in both periods. The association between using all 5 HIT types related to meaningful use and perceived quality was statistically significant in 2000-2001, but not in 2004-2005. Health information technology has become a multifunctional system and appears to have enhanced physicians' perception of providing high-quality care. Physicians' perceptions of medical care quality improved as the number of HIT types used increased. This study supports more extensive use of HIT in physician practices.

LncRNA-HIT Functions as an Epigenetic Regulator of Chondrogenesis through Its Recruitment of p100/CBP Complexes.

PubMed

Carlson, Hanqian L; Quinn, Jeffrey J; Yang, Yul W; Thornburg, Chelsea K; Chang, Howard Y; Stadler, H Scott

2015-12-01

Gene expression profiling in E 11 mouse embryos identified high expression of the long noncoding RNA (lncRNA), LNCRNA-HIT in the undifferentiated limb mesenchyme, gut, and developing genital tubercle. In the limb mesenchyme, LncRNA-HIT was found to be retained in the nucleus, forming a complex with p100 and CBP. Analysis of the genome-wide distribution of LncRNA-HIT-p100/CBP complexes by ChIRP-seq revealed LncRNA-HIT associated peaks at multiple loci in the murine genome. Ontological analysis of the genes contacted by LncRNA-HIT-p100/CBP complexes indicate a primary role for these loci in chondrogenic differentiation. Functional analysis using siRNA-mediated reductions in LncRNA-HIT or p100 transcripts revealed a significant decrease in expression of many of the LncRNA-HIT-associated loci. LncRNA-HIT siRNA treatments also impacted the ability of the limb mesenchyme to form cartilage, reducing mesenchymal cell condensation and the formation of cartilage nodules. Mechanistically the LncRNA-HIT siRNA treatments impacted pro-chondrogenic gene expression by reducing H3K27ac or p100 activity, confirming that LncRNA-HIT is essential for chondrogenic differentiation in the limb mesenchyme. Taken together, these findings reveal a fundamental epigenetic mechanism functioning during early limb development, using LncRNA-HIT and its associated proteins to promote the expression of multiple genes whose products are necessary for the formation of cartilage.

LncRNA-HIT Functions as an Epigenetic Regulator of Chondrogenesis through Its Recruitment of p100/CBP Complexes

PubMed Central

Carlson, Hanqian L.; Quinn, Jeffrey J.; Yang, Yul W.; Thornburg, Chelsea K.; Chang, Howard Y.; Stadler, H. Scott

2015-01-01

Gene expression profiling in E 11 mouse embryos identified high expression of the long noncoding RNA (lncRNA), LNCRNA-HIT in the undifferentiated limb mesenchyme, gut, and developing genital tubercle. In the limb mesenchyme, LncRNA-HIT was found to be retained in the nucleus, forming a complex with p100 and CBP. Analysis of the genome-wide distribution of LncRNA-HIT-p100/CBP complexes by ChIRP-seq revealed LncRNA-HIT associated peaks at multiple loci in the murine genome. Ontological analysis of the genes contacted by LncRNA-HIT-p100/CBP complexes indicate a primary role for these loci in chondrogenic differentiation. Functional analysis using siRNA-mediated reductions in LncRNA-HIT or p100 transcripts revealed a significant decrease in expression of many of the LncRNA-HIT-associated loci. LncRNA-HIT siRNA treatments also impacted the ability of the limb mesenchyme to form cartilage, reducing mesenchymal cell condensation and the formation of cartilage nodules. Mechanistically the LncRNA-HIT siRNA treatments impacted pro-chondrogenic gene expression by reducing H3K27ac or p100 activity, confirming that LncRNA-HIT is essential for chondrogenic differentiation in the limb mesenchyme. Taken together, these findings reveal a fundamental epigenetic mechanism functioning during early limb development, using LncRNA-HIT and its associated proteins to promote the expression of multiple genes whose products are necessary for the formation of cartilage. PMID:26633036

General Strain Theory and Substance Use among American Indian Adolescents.

PubMed

Eitle, Tamela McNulty; Eitle, David; Johnson-Jennings, Michelle

2013-01-01

Despite the well-established finding that American Indian adolescents are at a greater risk of illicit substance use and abuse than the general population, few generalist explanations of deviance have been extended to American Indian substance use. Using a popular generalist explanation of deviance, General Strain Theory, we explore the predictive utility of this model with a subsample of American Indian adolescents from waves one and two of the National Longitudinal Study of Adolescent Health (Add-Health). Overall, we find mixed support for the utility of General Strain Theory to account for American Indian adolescent substance use. While exposure to recent life events, a common measure of stress exposure, was found to be a robust indicator of substance use, we found mixed support for the thesis that negative affect plays a key role in mediating the link between strain and substance use. However, we did find evidence that personal and social resources serve to condition the link between stress exposure and substance use, with parental control, self-restraint, religiosity, and exposure to substance using peers each serving to moderate the association between strain and substance use, albeit in more complex ways than expected.

General Strain Theory and Substance Use among American Indian Adolescents

PubMed Central

Eitle, Tamela McNulty; Eitle, David; Johnson-Jennings, Michelle

2013-01-01

Despite the well-established finding that American Indian adolescents are at a greater risk of illicit substance use and abuse than the general population, few generalist explanations of deviance have been extended to American Indian substance use. Using a popular generalist explanation of deviance, General Strain Theory, we explore the predictive utility of this model with a subsample of American Indian adolescents from waves one and two of the National Longitudinal Study of Adolescent Health (Add-Health). Overall, we find mixed support for the utility of General Strain Theory to account for American Indian adolescent substance use. While exposure to recent life events, a common measure of stress exposure, was found to be a robust indicator of substance use, we found mixed support for the thesis that negative affect plays a key role in mediating the link between strain and substance use. However, we did find evidence that personal and social resources serve to condition the link between stress exposure and substance use, with parental control, self-restraint, religiosity, and exposure to substance using peers each serving to moderate the association between strain and substance use, albeit in more complex ways than expected. PMID:23826511

Team reasoning: Solving the puzzle of coordination.

PubMed

Colman, Andrew M; Gold, Natalie

2017-11-03

In many everyday activities, individuals have a common interest in coordinating their actions. Orthodox game theory cannot explain such intuitively obvious forms of coordination as the selection of an outcome that is best for all in a common-interest game. Theories of team reasoning provide a convincing solution by proposing that people are sometimes motivated to maximize the collective payoff of a group and that they adopt a distinctive mode of reasoning from preferences to decisions. This also offers a compelling explanation of cooperation in social dilemmas. A review of team reasoning and related theories suggests how team reasoning could be incorporated into psychological theories of group identification and social value orientation theory to provide a deeper understanding of these phenomena.

Hyperinsulin therapy for calcium channel antagonist poisoning: a seven-year retrospective study.

PubMed

Espinoza, Tamara R; Bryant, Sean M; Aks, Steve E

2013-01-01

The use of hyperinsulin therapy (HIT) in severe calcium channel antagonist (CCA) poisoning has become a more common therapy within the last decade. The objective of this study is to report 7 years of experience recommending HIT. This was a retrospective chart review utilizing our regional poison center (RPC) data from January 1, 2002, through December 31, 2008. All cases of CCA poisoning receiving HIT were searched. Endpoints included the number of CCA cases utilizing HIT, insulin dose, time of initiation of HIT, patient outcome, adverse events, age, glucose concentration, and lowest systolic blood pressure recorded. Forty-six cases of CCA poisoning were managed with HIT over 7 years. All the patients received standard antidotal therapy (= intravenous fluids, calcium salts, glucagon, and pressors). HIT administration followed our RPC recommendation 23 times (50%), and no hypoglycemic events occurred. Means (age, highest glucose measured, and lowest systolic blood pressure measured) were 51 years, 282 mg/dL, and 74 mm Hg, respectively. Our RPC recommendations for HIT were followed 50% of the time over the last 7 years. In light of the lack of hypoglycemia associated with HIT in our study population, we recommend HIT as an early and safe antidote in significant CCA poisoning.