WorldWideScience

Sample records for model suggested factor

  1. Hypnosis, suggestion, and suggestibility: an integrative model.

    Science.gov (United States)

    Lynn, Steven Jay; Laurence, Jean-Roch; Kirsch, Irving

    2015-01-01

    This article elucidates an integrative model of hypnosis that integrates social, cultural, cognitive, and neurophysiological variables at play both in and out of hypnosis and considers their dynamic interaction as determinants of the multifaceted experience of hypnosis. The roles of these variables are examined in the induction and suggestion stages of hypnosis, including how they are related to the experience of involuntariness, one of the hallmarks of hypnosis. It is suggested that studies of the modification of hypnotic suggestibility; cognitive flexibility; response sets and expectancies; the default-mode network; and the search for the neurophysiological correlates of hypnosis, more broadly, in conjunction with research on social psychological variables, hold much promise to further understanding of hypnosis.

  2. Baryogenesis model suggesting antigalaxies

    International Nuclear Information System (INIS)

    Kirilova, D.P.

    1998-12-01

    A non-GUT baryogenesis model, according to which our Universe may contain clusters of antigalaxies is discussed. A mechanism of separation of vast quantities of matter from such of antimatter is described. The provided analysis showed that for a natural range of model parameters a sufficient separation between matter and antimatter regions, required from observational data, can be obtained. (author)

  3. Factor structure of suggestibility revisited: new evidence for direct and indirect suggestibility

    Directory of Open Access Journals (Sweden)

    Romuald Polczyk

    2016-05-01

    Full Text Available Background Yielding to suggestions can be viewed as a relatively stable individual trait, called suggestibility. It has been long proposed that there are two kinds of suggestible influence, and two kinds of suggestibility corresponding to them: direct and indirect. Direct suggestion involves overt unhidden influence, while indirect suggestion concerns influence that is hidden, and the participant does not know that the suggestibility is being measured. So far however, empirical evidence for the existence of the two factors has been scarce. In the present study, more sophisticated and reliable tools for measuring suggestibility were applied than in the previous research, in the hope that better measurement would reveal the factor structure of suggestibility. Two tests of direct suggestibility were used: the Harvard Group Scale of Hypnotic Susceptibility, Form A, measuring hypnotic susceptibility, and the Barber Suggestibility Scale, measuring non-hypnotic direct imaginative suggestibility. Three tests served to measure indirect suggestibility: the Sensory Suggestibility Scale, measuring indirect suggestibility relating to perception; the Gudjonsson Suggestibility Scale, measuring the tendency to yield to suggestive questions and changing answers after negative feedback; and the Emotional Dialogs Tests, measuring the tendency to perceive nonexistent aggression. Participants and procedure In sum, 115 participants were tested, 69 women, 49 men, mean age 22.20 years, SD = 2.20. Participants were tested in two sessions, lasting for a total of four hours. Results Confirmatory factor analyses confirmed the existence of two uncorrelated factors of suggestibility: direct and indirect. Conclusions Suggestibility may indeed involve two factors, direct and indirect, and failure to discover them in previous research may be due to methodological problems.

  4. Quantitative histological models suggest endothermy in plesiosaurs

    Directory of Open Access Journals (Sweden)

    Corinna V. Fleischle

    2018-06-01

    Full Text Available Background Plesiosaurs are marine reptiles that arose in the Late Triassic and survived to the Late Cretaceous. They have a unique and uniform bauplan and are known for their very long neck and hydrofoil-like flippers. Plesiosaurs are among the most successful vertebrate clades in Earth’s history. Based on bone mass decrease and cosmopolitan distribution, both of which affect lifestyle, indications of parental care, and oxygen isotope analyses, evidence for endothermy in plesiosaurs has accumulated. Recent bone histological investigations also provide evidence of fast growth and elevated metabolic rates. However, quantitative estimations of metabolic rates and bone growth rates in plesiosaurs have not been attempted before. Methods Phylogenetic eigenvector maps is a method for estimating trait values from a predictor variable while taking into account phylogenetic relationships. As predictor variable, this study employs vascular density, measured in bone histological sections of fossil eosauropterygians and extant comparative taxa. We quantified vascular density as primary osteon density, thus, the proportion of vascular area (including lamellar infillings of primary osteons to total bone area. Our response variables are bone growth rate (expressed as local bone apposition rate and resting metabolic rate (RMR. Results Our models reveal bone growth rates and RMRs for plesiosaurs that are in the range of birds, suggesting that plesiosaurs were endotherm. Even for basal eosauropterygians we estimate values in the range of mammals or higher. Discussion Our models are influenced by the availability of comparative data, which are lacking for large marine amniotes, potentially skewing our results. However, our statistically robust inference of fast growth and fast metabolism is in accordance with other evidence for plesiosaurian endothermy. Endothermy may explain the success of plesiosaurs consisting in their survival of the end-Triassic extinction

  5. Critical Success Factors of Suggestions Systems. | Marx | IFE ...

    African Journals Online (AJOL)

    A literature study approach is followed to establish which factors contribute to the success and failure of various suggestion systems. It was found ... The value of the paper firstly, shows the importance of creativity and innovation within the organisation's own culture and the framework of a formal suggestion system. Secondly ...

  6. Suggestion of Islamic Insurance Company Model

    OpenAIRE

    Abdullah Ibrahim Nazal

    2015-01-01

    This study is one of very few studies which have investigated Islamic Insurance Companies as solution. It explained its operations also comparing with Traditional Insurance Companies and theoretical Islamic insurance models. As result to this study Islamic Insurance companies are profit organization. It helps Islamic banks but it costs customer to face expect risk. Islamic Insurance companies have many ways to get profits and consider all customers installments grants. Its operation gap comes...

  7. The Prevalence of Risk Factors of Coronary Artery Disease in the Patients who Underwent Coronary Artery Bypass Graft, Shiraz, Iran: Suggesting a Model

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Ostovan

    2014-12-01

    Full Text Available Background: Cardiovascular diseases are the main cause of 40% of deaths in Iran annually. Many patients undergoing coronary artery bypass graft surgery have previous cardiovascular risk factors which could be prevented. Objectives: The present study aimed to assess the prevalence of cardiovascular risk factors in the patients undergoing coronary artery bypass graft surgery. Materials and Methods: In this cross-sectional (descriptive – analytical study, a data collecting form was used. A total of 246 patients were selected from six hospitals of Shiraz using random stratification. Descriptive statistics were presented through figures and tables and t-test was used to analyze the continuous variables. All the statistical analyses were performed using the SPSS statistical software (version 15.0. Besides, P < 0.05 was considered as statistically significant. Results: Among the study patients, only 11.67% had no risk factors and 88.33% had one or more risk factors. The most common risk factors observed in the patients were hypertension, obesity and overweight, hyperlipidemia, and diabetes mellitus. The results showed a significant difference between males and females regarding the prevalence of hypertension (P = 0.001, diabetes (P = 0.028, hypercholesterolemia (P = 0.020, and cigarette smoking (P = 0.001. In addition, the patients' mean levels of cholesterol, LDL, triglyceride, and fasting blood sugar were higher than the acceptable level, while that of HDL was lower than the accepted level. Conclusions:: These patients are recommended to be trained regarding lifestyle changes. Also, prevention strategies can play an important role in reducing patient morbidity and mortality.

  8. Factor structure of suggestibility revisited: new evidence for direct and indirect suggestibility

    OpenAIRE

    Romuald Polczyk

    2016-01-01

    Background Yielding to suggestions can be viewed as a relatively stable individual trait, called suggestibility. It has been long proposed that there are two kinds of suggestible influence, and two kinds of suggestibility corresponding to them: direct and indirect. Direct suggestion involves overt unhidden influence, while indirect suggestion concerns influence that is hidden, and the participant does not know that the suggestibility is being measured. So far however, empirical evidence ...

  9. Simple suggestions for including vertical physics in oil spill models

    International Nuclear Information System (INIS)

    D'Asaro, Eric; University of Washington, Seatle, WA

    2001-01-01

    Current models of oil spills include no vertical physics. They neglect the effect of vertical water motions on the transport and concentration of floating oil. Some simple ways to introduce vertical physics are suggested here. The major suggestion is to routinely measure the density stratification of the upper ocean during oil spills in order to develop a database on the effect of stratification. (Author)

  10. Sustainable Competitive Advantage for Educational Institutions: A Suggested Model.

    Science.gov (United States)

    Mazzarol, Tim; Soutar, Geoffrey Norman

    1999-01-01

    Outlines a model of factors critical to establishing and maintaining sustainable competitive advantage for education-services enterprises in international markets. The model, which combines industrial economics, management theory, and services marketing, seeks to explain the strategic decision-making environment in which the education exporter…

  11. Using suggestion to model different types of automatic writing.

    Science.gov (United States)

    Walsh, E; Mehta, M A; Oakley, D A; Guilmette, D N; Gabay, A; Halligan, P W; Deeley, Q

    2014-05-01

    Our sense of self includes awareness of our thoughts and movements, and our control over them. This feeling can be altered or lost in neuropsychiatric disorders as well as in phenomena such as "automatic writing" whereby writing is attributed to an external source. Here, we employed suggestion in highly hypnotically suggestible participants to model various experiences of automatic writing during a sentence completion task. Results showed that the induction of hypnosis, without additional suggestion, was associated with a small but significant reduction of control, ownership, and awareness for writing. Targeted suggestions produced a double dissociation between thought and movement components of writing, for both feelings of control and ownership, and additionally, reduced awareness of writing. Overall, suggestion produced selective alterations in the control, ownership, and awareness of thought and motor components of writing, thus enabling key aspects of automatic writing, observed across different clinical and cultural settings, to be modelled. Copyright © 2014. Published by Elsevier Inc.

  12. Training, Quality Assurance Factors, and Tools Investigation: a Work Report and Suggestions on Software Quality Assurance

    Science.gov (United States)

    Lee, Pen-Nan

    1991-01-01

    Previously, several research tasks have been conducted, some observations were obtained, and several possible suggestions have been contemplated involving software quality assurance engineering at NASA Johnson. These research tasks are briefly described. Also, a brief discussion is given on the role of software quality assurance in software engineering along with some observations and suggestions. A brief discussion on a training program for software quality assurance engineers is provided. A list of assurance factors as well as quality factors are also included. Finally, a process model which can be used for searching and collecting software quality assurance tools is presented.

  13. Modelling of Arabidopsis LAX3 expression suggests auxin homeostasis.

    Science.gov (United States)

    Mellor, Nathan; Péret, Benjamin; Porco, Silvana; Sairanen, Ilkka; Ljung, Karin; Bennett, Malcolm; King, John

    2015-02-07

    Emergence of new lateral roots from within the primary root in Arabidopsis has been shown to be regulated by the phytohormone auxin, via the expression of the auxin influx carrier LAX3, mediated by the ARF7/19 IAA14 signalling module (Swarup et al., 2008). A single cell model of the LAX3 and IAA14 auxin response was formulated and used to demonstrate that hysteresis and bistability may explain the experimentally observed 'all-or-nothing' LAX3 spatial expression pattern in cortical cells containing a gradient of auxin concentrations. The model was tested further by using a parameter fitting algorithm to match model output with qRT-PCR mRNA expression data following exogenous auxin treatment. It was found that the model is able to show good agreement with the data, but only when the exogenous auxin signal is degraded over time, at a rate higher than that measured in the experimental medium, suggesting the triggering of an endogenous auxin homeostasis mechanism. Testing the model over a more physiologically relevant range of extracellular auxin shows bistability and hysteresis still occur when using the optimised parameters, providing the rate of LAX3 active auxin transport is sufficiently high relative to passive diffusion. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Models and theories of prescribing decisions: A review and suggested a new model.

    Science.gov (United States)

    Murshid, Mohsen Ali; Mohaidin, Zurina

    2017-01-01

    To date, research on the prescribing decisions of physician lacks sound theoretical foundations. In fact, drug prescribing by doctors is a complex phenomenon influenced by various factors. Most of the existing studies in the area of drug prescription explain the process of decision-making by physicians via the exploratory approach rather than theoretical. Therefore, this review is an attempt to suggest a value conceptual model that explains the theoretical linkages existing between marketing efforts, patient and pharmacist and physician decision to prescribe the drugs. The paper follows an inclusive review approach and applies the previous theoretical models of prescribing behaviour to identify the relational factors. More specifically, the report identifies and uses several valuable perspectives such as the 'persuasion theory - elaboration likelihood model', the stimuli-response marketing model', the 'agency theory', the theory of planned behaviour,' and 'social power theory,' in developing an innovative conceptual paradigm. Based on the combination of existing methods and previous models, this paper suggests a new conceptual model of the physician decision-making process. This unique model has the potential for use in further research.

  15. Models and theories of prescribing decisions: A review and suggested a new model

    Science.gov (United States)

    Mohaidin, Zurina

    2017-01-01

    To date, research on the prescribing decisions of physician lacks sound theoretical foundations. In fact, drug prescribing by doctors is a complex phenomenon influenced by various factors. Most of the existing studies in the area of drug prescription explain the process of decision-making by physicians via the exploratory approach rather than theoretical. Therefore, this review is an attempt to suggest a value conceptual model that explains the theoretical linkages existing between marketing efforts, patient and pharmacist and physician decision to prescribe the drugs. The paper follows an inclusive review approach and applies the previous theoretical models of prescribing behaviour to identify the relational factors. More specifically, the report identifies and uses several valuable perspectives such as the ‘persuasion theory - elaboration likelihood model’, the stimuli–response marketing model’, the ‘agency theory’, the theory of planned behaviour,’ and ‘social power theory,’ in developing an innovative conceptual paradigm. Based on the combination of existing methods and previous models, this paper suggests a new conceptual model of the physician decision-making process. This unique model has the potential for use in further research. PMID:28690701

  16. Models and theories of prescribing decisions: A review and suggested a new model

    Directory of Open Access Journals (Sweden)

    Ali Murshid M

    2017-06-01

    Full Text Available To date, research on the prescribing decisions of physician lacks sound theoretical foundations. In fact, drug prescribing by doctors is a complex phenomenon influenced by various factors. Most of the existing studies in the area of drug prescription explain the process of decision-making by physicians via the exploratory approach rather than theoretical. Therefore, this review is an attempt to suggest a value conceptual model that explains the theoretical linkages existing between marketing efforts, patient and pharmacist and physician decision to prescribe the drugs. The paper follows an inclusive review approach and applies the previous theoretical models of prescribing behaviour to identify the relational factors. More specifically, the report identifies and uses several valuable perspectives such as the ‘persuasion theory - elaboration likelihood model’, the stimuli–response marketing model’, the ‘agency theory’, the theory of planned behaviour,’ and ‘social power theory,’ in developing an innovative conceptual paradigm. Based on the combination of existing methods and previous models, this paper suggests a new conceptual model of the physician decision-making process. This unique model has the potential for use in further research.

  17. Suggestion of a Management Model: Total Entropy Management

    OpenAIRE

    Goksel Alpan,; Ismail Efil

    2011-01-01

    “Entropy” can be defined as the measure of disorder, uncertainty and consumed energy in a system or in the Universe. In the study, entropy concept is used as metaphor and it is aimed to construct the conceptual basis of a new management model which can be utilized to manage all entropy sources effectively. The study is conveyed with a multidisciplinary and holistic approach and by the use of qualitative research techniques. In the study, it is examined the relations of the entropy concept wit...

  18. A Model Suggestion to Predict Leverage Ratio for Construction Projects

    Directory of Open Access Journals (Sweden)

    Özlem Tüz

    2013-12-01

    Full Text Available Due to the nature, construction is an industry with high uncertainty and risk. Construction industry carries high leverage ratios. Firms with low equities work in big projects through progress payment system, but in this case, even a small negative in the planned cash flows constitute a major risk for the company.The use of leverage, with a small investment to achieve profit targets large-scale, high-profit, but also brings a high risk with it. Investors may lose all or the portion of the money. In this study, monitoring and measuring of the leverage ratio because of the displacement in cash inflows of construction projects which uses high leverage and low cash to do business in the sector is targeted. Cash need because of drifting the cash inflows may be seen due to the model. Work should be done in the early stages of the project with little capital but in the later stages, rapidly growing capital need arises.The values obtained from the model may be used to supply the capital held in the right time by anticipating the risks because of the delay in cashflow of construction projects which uses high leverage ratio.

  19. Neurotransmitter systems and neurotrophic factors in autism: association study of 37 genes suggests involvement of DDC.

    Science.gov (United States)

    Toma, Claudio; Hervás, Amaia; Balmaña, Noemí; Salgado, Marta; Maristany, Marta; Vilella, Elisabet; Aguilera, Francisco; Orejuela, Carmen; Cuscó, Ivon; Gallastegui, Fátima; Pérez-Jurado, Luis Alberto; Caballero-Andaluz, Rafaela; Diego-Otero, Yolanda de; Guzmán-Alvarez, Guadalupe; Ramos-Quiroga, Josep Antoni; Ribasés, Marta; Bayés, Mònica; Cormand, Bru

    2013-09-01

    Neurotransmitter systems and neurotrophic factors can be considered strong candidates for autism spectrum disorder (ASD). The serotoninergic and dopaminergic systems are involved in neurotransmission, brain maturation and cortical organization, while neurotrophic factors (NTFs) participate in neurodevelopment, neuronal survival and synapses formation. We aimed to test the contribution of these candidate pathways to autism through a case-control association study of genes selected both for their role in central nervous system functions and for pathophysiological evidences. The study sample consisted of 326 unrelated autistic patients and 350 gender-matched controls from Spain. We genotyped 369 tagSNPs to perform a case-control association study of 37 candidate genes. A significant association was obtained between the DDC gene and autism in the single-marker analysis (rs6592961, P = 0.00047). Haplotype-based analysis pinpointed a four-marker combination in this gene associated with the disorder (rs2329340C-rs2044859T-rs6592961A-rs11761683T, P = 4.988e-05). No significant results were obtained for the remaining genes after applying multiple testing corrections. However, the rs167771 marker in DRD3, associated with ASD in a previous study, displayed a nominal association in our analysis (P = 0.023). Our data suggest that common allelic variants in the DDC gene may be involved in autism susceptibility.

  20. Low modeled ozone production suggests underestimation of precursor emissions (especially NOx in Europe

    Directory of Open Access Journals (Sweden)

    E. Oikonomakis

    2018-02-01

    (where both NOx and VOC emissions are increased leads to a better model performance. Although increasing only the traffic NOx emissions by a factor of 4 gave very similar results to the doubling of all NOx emissions, the first scenario is more consistent with the uncertainties reported by other studies than the latter, suggesting that high uncertainties in NOx emissions might originate mainly from the road-transport sector rather than from other sectors. The impact of meteorology was examined with three sensitivity tests: (i increased surface temperature by 4 °C, (ii reduced wind speed by 50 % and (iii doubled wind speed. The first two scenarios led to a consistent increase in all surface ozone mixing ratios, thus improving the model performance for the high ozone values but significantly degrading it for the low ozone values, while the third scenario had exactly the opposite effects. Overall, the modeled ozone is predicted to be more sensitive to its precursor emissions (especially traffic NOx and therefore their uncertainties, which seem to be responsible for the model underestimation of the observed high ozone mixing ratios and ozone production.

  1. Model Correction Factor Method

    DEFF Research Database (Denmark)

    Christensen, Claus; Randrup-Thomsen, Søren; Morsing Johannesen, Johannes

    1997-01-01

    The model correction factor method is proposed as an alternative to traditional polynomial based response surface techniques in structural reliability considering a computationally time consuming limit state procedure as a 'black box'. The class of polynomial functions is replaced by a limit...... of the model correction factor method, is that in simpler form not using gradient information on the original limit state function or only using this information once, a drastic reduction of the number of limit state evaluation is obtained together with good approximations on the reliability. Methods...

  2. Factors to consider in monitoring programs suggested by statistical analysis of available data

    International Nuclear Information System (INIS)

    Thomas, J.M.

    1977-01-01

    Based on experience gained in the statistical analysis of data collected during monitoring programs at three nuclear power plants, as well as on other studies in the area of impact assessment, I have attempted to outline what has been done and what I believe can be done in assessing environmental changes. Procedural changes that I suggest include the implementation of a stopping rule so field studies are terminated after a negotiated period of time and the commitment of all resources to studies of one or two species. Simulation models are suggested as a useful tool in an iterative process where results of field studies are routinely incorporated until a negotiated stopping time is reached or until acceptable results are attained. Finally, I describe the statistical analyses we have used and their limitations, and I give some sample-size estimates needed to detect changes of specified sizes in population numbers. To detect changes in population numbers of the size we have encountered, calculated sample sizes are found to be much larger than in current use

  3. Low modeled ozone production suggests underestimation of precursor emissions (especially NOx) in Europe

    Science.gov (United States)

    Oikonomakis, Emmanouil; Aksoyoglu, Sebnem; Ciarelli, Giancarlo; Baltensperger, Urs; Prévôt, André Stephan Henry

    2018-02-01

    High surface ozone concentrations, which usually occur when photochemical ozone production takes place, pose a great risk to human health and vegetation. Air quality models are often used by policy makers as tools for the development of ozone mitigation strategies. However, the modeled ozone production is often not or not enough evaluated in many ozone modeling studies. The focus of this work is to evaluate the modeled ozone production in Europe indirectly, with the use of the ozone-temperature correlation for the summer of 2010 and to analyze its sensitivity to precursor emissions and meteorology by using the regional air quality model, the Comprehensive Air Quality Model with Extensions (CAMx). The results show that the model significantly underestimates the observed high afternoon surface ozone mixing ratios (≥ 60 ppb) by 10-20 ppb and overestimates the lower ones (degradation of the model performance for the lower ozone mixing ratios. The model performance for ozone-temperature correlation is also better when NOx emissions are doubled. In the Benelux area, however, the third scenario (where both NOx and VOC emissions are increased) leads to a better model performance. Although increasing only the traffic NOx emissions by a factor of 4 gave very similar results to the doubling of all NOx emissions, the first scenario is more consistent with the uncertainties reported by other studies than the latter, suggesting that high uncertainties in NOx emissions might originate mainly from the road-transport sector rather than from other sectors. The impact of meteorology was examined with three sensitivity tests: (i) increased surface temperature by 4 °C, (ii) reduced wind speed by 50 % and (iii) doubled wind speed. The first two scenarios led to a consistent increase in all surface ozone mixing ratios, thus improving the model performance for the high ozone values but significantly degrading it for the low ozone values, while the third scenario had exactly the

  4. Nerve growth factor receptor immunostaining suggests an extrinsic origin for hypertrophic nerves in Hirschsprung's disease.

    OpenAIRE

    Kobayashi, H; O'Briain, D S; Puri, P

    1994-01-01

    The expression of nerve growth factor receptor in colon from 20 patients with Hirshsprung's disease and 10 controls was studied immunohistochemically. The myenteric and submucous plexuses in the ganglionic bowel and hypertrophic nerve trunks in the aganglionic bowel displayed strong expression of nerve growth factor receptor. The most important finding was the identical localisation of nerve growth factor receptor immunoreactivity on the perineurium of both hypertrophic nerve trunks in Hirshs...

  5. İnternet Üzerinden Alışveriş Niyetini Etkileyen Faktörlerin Genişletilmiş Teknoloji Kabul Modeli Kullanarak İncelenmesi Ve Bir Model Önerisi ( An Investigation And A Model Suggestion For Factors Affecting Online Shopping Intention Using Extended Technology Acceptance Model

    Directory of Open Access Journals (Sweden)

    Cengiz YILMAZ

    2015-12-01

    the buying intensions of internet consumers. Therefore, in order to understand those intensions, this study inspired from Technology Acceptance Model (TAM which was developed by Davis in 1989. The data used in this research is gathered from a sample of 680 internet users and with the help of the relevant theory, the factors affecting online shopping intention are analyzed by structural equation modelling. In addition to perceived ease of use, perceived usefulness, perceived enjoyment, attitude and intention, information quality, perceived system quality, perceived service quality, store familiarity, trust and subjective norm variables are also used in the model. The proposed model submitted sufficient goodness of fit values. According to the findings of the research, it can be said that except of subjective norm, all other path coefficients between variables are significant. Subjective norm does not play any role in determining the consumers online shopping intention.

  6. Is the dissociative adult suggestible? A test of the trauma and fantasy models of dissociation.

    Science.gov (United States)

    Kluemper, Nicole S; Dalenberg, Constance

    2014-01-01

    Psychologists have long assumed a connection between traumatic experience and psychological dissociation. This hypothesis is referred to as the trauma model of dissociation. In the past decade, a series of papers have been published that question this traditional causal link, proposing an alternative fantasy model of dissociation. In the present research, the relationship among dissociation, suggestibility, and fantasy proneness was examined. Suggestibility was measured through the Gudjonsson Scale of Interrogative Suggestibility (GSS) as well as an autobiographically based version of this measure based on the events of September 11, 2001. Consistent with prior research and with the trauma model, dissociation correlated positively with trauma severity (r = .32, p suggestibility measure. Although some participants did become quite emotional during the procedure, the risk/benefit ratio was perceived by almost all participants to be positive, with more reactive individuals evaluating the procedure more positively. The results consistently support the trauma model of dissociation and fail to support the fantasy model of dissociation.

  7. The confounding factors leading to plagiarism in academic writing and some suggested remedies: A systematic review.

    Science.gov (United States)

    Guraya, Salman Yousuf; Guraya, Shaista Salman

    2017-05-01

    There is a staggering upsurge in the incidence of plagiarism of scientific literature. Literature shows divergent views about the factors that make plagiarism reprehensible. This review explores the causes and remedies for the perennial academic problem of plagiarism. Data sources were searched for full text English language articles published from 2000 to 2015. Data selection was done using medical subject headline (MeSH) terms plagiarism, unethical writing, academic theft, retraction, medical field, and plagiarism detection software. Data extraction was undertaken by selecting titles from retrieved references and data synthesis identified key factors leading to plagiarism such as unawareness of research ethics, poor writing skills and pressure or publish mantra. Plagiarism can be managed by a balance among its prevention, detection by plagiarism detection software, and institutional sanctions against proven plagiarists. Educating researchers about ethical principles of academic writing and institutional support in training writers about academic integrity and ethical publications can curtail plagiarism.

  8. Virulence factor rtx in Legionella pneumophila, evidence suggesting it is a modular multifunctional protein

    Directory of Open Access Journals (Sweden)

    Pelaz Carmen

    2008-01-01

    Full Text Available Abstract Background The repeats in toxin (Rtx are an important pathogenicity factor involved in host cells invasion of Legionella pneumophila and other pathogenic bacteria. Its role in escaping the host immune system and cytotoxic activity is well known. Its repeated motives and modularity make Rtx a multifunctional factor in pathogenicity. Results The comparative analysis of rtx gene among 6 strains of L. pneumophila showed modularity in their structures. Among compared genomes, the N-terminal region of the protein presents highly dissimilar repeats with functionally similar domains. On the contrary, the C-terminal region is maintained with a fashionable modular configuration, which gives support to its proposed role in adhesion and pore formation. Despite the variability of rtx among the considered strains, the flanking genes are maintained in synteny and similarity. Conclusion In contrast to the extracellular bacteria Vibrio cholerae, in which the rtx gene is highly conserved and flanking genes have lost synteny and similarity, the gene region coding for the Rtx toxin in the intracellular pathogen L. pneumophila shows a rapid evolution. Changes in the rtx could play a role in pathogenicity. The interplay of the Rtx toxin with host membranes might lead to the evolution of new variants that are able to escape host cell defences.

  9. NAGRA - Sites for geological repositories - Technical safety factors: Suggestions for stage 3

    International Nuclear Information System (INIS)

    2015-01-01

    This comprehensive brochure published by the Swiss National Cooperative for the Disposal of Radioactive Waste (NAGRA) examines the six sites for repositories for nuclear wastes in Switzerland which have been proposed in Stage 1 of the program concerning nuclear waste repositories. Three of these sites are proposed for both highly radioactive wastes as well as for low and medium-active wastes, the other three for low and medium-active wastes only. The evaluation of the sites is discussed. The sites are to be further evaluated in Stage 2 of the program. The work to be done in the further stages involved in the selection of the final site (or sites) is described. Along with definition of the regions where deep repositories could possibly be built, suggestions for the placing of the facilities required on the surface are discussed. Geological requirements on the repositories and safety-relevant characteristics of the various site options are discussed. The results of the assessments made are presented in tabular form. Maps and geological cross-sections of all the suggested areas are included

  10. Sugar-Sweetened Beverages: Children's Perceptions, Factors of Influence, and Suggestions for Reducing Intake.

    Science.gov (United States)

    Battram, Danielle S; Piché, Leonard; Beynon, Charlene; Kurtz, Joanne; He, Meizi

    2016-01-01

    This study aimed to gain an in-depth understanding of children's perceptions of sugar-sweetened beverages (SSBs). Nine focus groups were conducted in grade 5 and 6 elementary schoolchildren. Nine urban and rural elementary schools in London, Ontario, Canada. Fifty-one children, 58% of which were male, 52% of whom were in grade 5, and 84% of whom were Caucasian. Children's views on sugar-sweetened beverages. Three researchers conducted inductive content analysis on the data independently using the principles of the immersion-crystallization method. Participants had a high level of awareness of beverages and their health effects, which was primarily targeted at the sugar content. Dominant factors that influenced children's beverage choices and consumption patterns included taste, parental control practices, accessibility, and advertising. Participants identified a wide array of strategies to reduce SSB consumption in children, including educational strategies for both children and parents and policy-level changes at both the government and school levels. Despite a high level of awareness of SSBs, children believed that further education and policies regarding SSBs were warranted. These data may prove helpful in designing effective interventions targeted at children and parents to reduce SSB consumption by children. Copyright © 2016 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

  11. Metabolomics analysis and modeling suggest a lysophosphocholines-PAF receptor interaction in fibromyalgia.

    Directory of Open Access Journals (Sweden)

    Pierluigi Caboni

    Full Text Available Fibromyalgia Syndrome (FMS is a chronic disease characterized by widespread pain, and difficult to diagnose and treat. We analyzed the plasma metabolic profile of patients with FMS by using a metabolomics approach combining Liquid Chromatography-Quadrupole-Time Of Flight/Mass Spectrometry (LC-Q-TOF/MS with multivariate statistical analysis, aiming to discriminate patients and controls. LC-Q-TOF/MS analysis of plasma (FMS patients: n = 22 and controls: n = 21 identified many lipid compounds, mainly lysophosphocholines (lysoPCs, phosphocholines and ceramides. Multivariate statistical analysis was performed to identify the discriminating metabolites. A protein docking and molecular dynamic (MD study was then performed, using the most discriminating lysoPCs, to validate the binding to Platelet Activating Factor (1-alkyl-2-acetyl-sn-glycero-3-phosphocholine, PAF Receptor (PAFr. Discriminating metabolites between FMS patients and controls were identified as 1-tetradecanoyl-sn-glycero-3-phosphocholine [PC(14:0/0:0] and 1-hexadecanoyl-sn-glycero-3-phosphocholine [PC(16:0/0:0]. MD and docking indicate that the ligands investigated have similar potentialities to activate the PAFr receptor. The application of a metabolomic approach discriminated FMS patients from controls, with an over-representation of PC(14:0/0:0 and PC(16:0/0:0 compounds in the metabolic profiles. These results and the modeling of metabolite-PAFr interaction, allowed us to hypothesize that lipids oxidative fragmentation might generate lysoPCs in abundance, that in turn will act as PAF-like bioactivators. Overall results suggest disease biomarkers and potential therapeutical targets for FMS.

  12. Mentoring for junior medical faculty: Existing models and suggestions for low-resource settings.

    Science.gov (United States)

    Menon, Vikas; Muraleedharan, Aparna; Bhat, Ballambhattu Vishnu

    2016-02-01

    Globally, there is increasing recognition about the positive benefits and impact of mentoring on faculty retention rates, career satisfaction and scholarly output. However, emphasis on research and practice of mentoring is comparatively meagre in low and middle income countries. In this commentary, we critically examine two existing models of mentorship for medical faculty and offer few suggestions for an integrated hybrid model that can be adapted for use in low resource settings. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. A trophic model of fringing coral reefs in Nanwan Bay, southern Taiwan suggests overfishing.

    Science.gov (United States)

    Liu, Pi-Jen; Shao, Kwang-Tsao; Jan, Rong-Quen; Fan, Tung-Yung; Wong, Saou-Lien; Hwang, Jiang-Shiou; Chen, Jen-Ping; Chen, Chung-Chi; Lin, Hsing-Juh

    2009-09-01

    Several coral reefs of Nanwan Bay, Taiwan have recently undergone shifts to macroalgal or sea anemone dominance. Thus, a mass-balance trophic model was constructed to analyze the structure and functioning of the food web. The fringing reef model was comprised of 18 compartments, with the highest trophic level of 3.45 for piscivorous fish. Comparative analyses with other reef models demonstrated that Nanwan Bay was similar to reefs with high fishery catches. While coral biomass was not lower, fish biomass was lower than those of reefs with high catches. Consequently, the sums of consumption and respiratory flows and total system throughput were also decreased. The Nanwan Bay model potentially suggests an overfished status in which the mean trophic level of the catch, matter cycling, and trophic transfer efficiency are extremely reduced.

  14. Model selection approach suggests causal association between 25-hydroxyvitamin D and colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Lina Zgaga

    Full Text Available Vitamin D deficiency has been associated with increased risk of colorectal cancer (CRC, but causal relationship has not yet been confirmed. We investigate the direction of causation between vitamin D and CRC by extending the conventional approaches to allow pleiotropic relationships and by explicitly modelling unmeasured confounders.Plasma 25-hydroxyvitamin D (25-OHD, genetic variants associated with 25-OHD and CRC, and other relevant information was available for 2645 individuals (1057 CRC cases and 1588 controls and included in the model. We investigate whether 25-OHD is likely to be causally associated with CRC, or vice versa, by selecting the best modelling hypothesis according to Bayesian predictive scores. We examine consistency for a range of prior assumptions.Model comparison showed preference for the causal association between low 25-OHD and CRC over the reverse causal hypothesis. This was confirmed for posterior mean deviances obtained for both models (11.5 natural log units in favour of the causal model, and also for deviance information criteria (DIC computed for a range of prior distributions. Overall, models ignoring hidden confounding or pleiotropy had significantly poorer DIC scores.Results suggest causal association between 25-OHD and colorectal cancer, and support the need for randomised clinical trials for further confirmations.

  15. Authority Delegation in Boyerahmad Health Centers through Model to Combine Suggestions System and Delphi Method 2012

    Directory of Open Access Journals (Sweden)

    M Momeninezhad

    2013-11-01

    Full Text Available Background & aim: Authority delegation means to transmit part of organization`s manager and leader`s special authorities and executive duties, regardless its root to subordinates and heads of units and related offices to speed up implementing affairs and organizational purposes quickly and on time. The purpose of this study was to inspect authority delegation in health centers of Boyerahmad district through using model to combine suggestions (to identify process and Delphi method (expert`s opinions . Methods: This cross-sectional study was implemented in two stages at first stage, research community was authorities of Boyerahmad health centers (58 persons, their suggestions about requested processes to delegate were gathered by total count through open questionnaires and in second stage, which was Delphi, suggestions gathered from previous stage judged by 30 experts. Data of both stages analyzed by help of Chi-square, correlation coefficient tests. Results: Findings showed that 73.85% of suggestions were able to be delegated, based on expert`s opinion. 40% of suggestions were in domain of official, 36.92% financial and 23.08% hygienic. 88% less than 6 years management background. 20.69% had no academic studies and only 27% were general physicians. Conclusion: By participation of environmental management levels, several processes may be specified and identify cases which are possible to delegate them executively using Delphi (expert`s opinion and this model can be used as a trust worthy method to delegate authority for decentralization. Key words: Participation Management, Health centers, Authority delegation

  16. A computational model of the LGI1 protein suggests a common binding site for ADAM proteins.

    Directory of Open Access Journals (Sweden)

    Emanuela Leonardi

    Full Text Available Mutations of human leucine-rich glioma inactivated (LGI1 gene encoding the epitempin protein cause autosomal dominant temporal lateral epilepsy (ADTLE, a rare familial partial epileptic syndrome. The LGI1 gene seems to have a role on the transmission of neuronal messages but the exact molecular mechanism remains unclear. In contrast to other genes involved in epileptic disorders, epitempin shows no homology with known ion channel genes but contains two domains, composed of repeated structural units, known to mediate protein-protein interactions.A three dimensional in silico model of the two epitempin domains was built to predict the structure-function relationship and propose a functional model integrating previous experimental findings. Conserved and electrostatic charged regions of the model surface suggest a possible arrangement between the two domains and identifies a possible ADAM protein binding site in the β-propeller domain and another protein binding site in the leucine-rich repeat domain. The functional model indicates that epitempin could mediate the interaction between proteins localized to different synaptic sides in a static way, by forming a dimer, or in a dynamic way, by binding proteins at different times.The model was also used to predict effects of known disease-causing missense mutations. Most of the variants are predicted to alter protein folding while several other map to functional surface regions. In agreement with experimental evidence, this suggests that non-secreted LGI1 mutants could be retained within the cell by quality control mechanisms or by altering interactions required for the secretion process.

  17. Shell model and spectroscopic factors

    International Nuclear Information System (INIS)

    Poves, P.

    2007-01-01

    In these lectures, I introduce the notion of spectroscopic factor in the shell model context. A brief review is given of the present status of the large scale applications of the Interacting Shell Model. The spectroscopic factors and the spectroscopic strength are discussed for nuclei in the vicinity of magic closures and for deformed nuclei. (author)

  18. Mathematical representation of bolted-joint stiffness: A new suggested model

    Energy Technology Data Exchange (ETDEWEB)

    Haidar, Nawras; Obeed, Salwan; Jawad, Mohamed [College of Engineering, University of Babylon, Babel (Iraq)

    2011-11-15

    Joint member stiffness in a bolted connection directly influences the safety of a design in regard to both static and fatigue loading, as well as in the prevention of separation in the connection. This work provides a new simple model for computing the member stiffness in bolted connections for both fully and partially developed stress envelope fields. The new model is built using a stress distribution polynomial of third order. Finite element analysis (FEA) is performed for some joints geometries, and the results are used to estimate the best analytical envelope angle in the proposed analytical model that gives suitable convergence between the compared results. An experimental effort is exerted to validate the accuracy of a suggested model. When analytical results are compared with FEA results and experimental data, the maximum absolute percentage errors are found to be 2.69 and 14.69, respectively. Also, a good agreement is obtained when the analytical results are compared with other researchers' results.

  19. Evaluation of the white finger risk prediction model in ISO 5349 suggests need for prospective studies.

    Science.gov (United States)

    Gemne, G; Lundström, R

    1996-05-01

    The risk prediction model for white fingers in Annex A of ISO 5349 is not likely to offer protection from all tools and all work processes. It is also probable that some work place changes it has initiated are either redundant or lack the intended effect. The main reasons for these shortcomings are the following. The often demonstrated disagreement between predicted and observed white fingers occurrence may be related to the fact that the model is based on latency data. This leads to an overestimation, to an unknown extent, of true group risks. A possible healthy worker effect, resulting in underestimation, has not been considered, and uncertainty because of recall bias is connected with using latency as effect variable in a slowly developing disorder like white fingers. The diagnostic criteria for white fingers have varied over the years, causing a possible inclusion of circulatory disturbances other than those induced by vibration. Among insufficiently clarified matters unrelated to vibration are variations in individual susceptibility and other host factors that modify vibration effects, uncertainty concerning daily or total effective exposure, and the fact that variation in work methods and processes as well as ergonomic factors other than vibration tend to make different groups incomparable form the viewpoint of risk of injury. Lack of sufficient data on vibration measurements and employment durations add to the uncertainty, as do variations in tool conditions (grinder wheels, etc) and inherent difficulties in measurement. Finally, the ISO 5349 frequency-weighting curve only relates to acute sensory effects rather than chronic effects on vascular functions like white fingers, and directional difference in sensitivity has not been incorporated in the curve. Data on exposure-response relationships are needed from prospective studies that monitor the dose of exposure to special vibration types and all relevant environmental agents, employ diagnostics with good

  20. Modeling of glycerol-3-phosphate transporter suggests a potential 'tilt' mechanism involved in its function.

    Science.gov (United States)

    Tsigelny, Igor F; Greenberg, Jerry; Kouznetsova, Valentina; Nigam, Sanjay K

    2008-10-01

    Many major facilitator superfamily (MFS) transporters have similar 12-transmembrane alpha-helical topologies with two six-helix halves connected by a long loop. In humans, these transporters participate in key physiological processes and are also, as in the case of members of the organic anion transporter (OAT) family, of pharmaceutical interest. Recently, crystal structures of two bacterial representatives of the MFS family--the glycerol-3-phosphate transporter (GlpT) and lac-permease (LacY)--have been solved and, because of assumptions regarding the high structural conservation of this family, there is hope that the results can be applied to mammalian transporters as well. Based on crystallography, it has been suggested that a major conformational "switching" mechanism accounts for ligand transport by MFS proteins. This conformational switch would then allow periodic changes in the overall transporter configuration, resulting in its cyclic opening to the periplasm or cytoplasm. Following this lead, we have modeled a possible "switch" mechanism in GlpT, using the concept of rotation of protein domains as in the DynDom program17 and membranephilic constraints predicted by the MAPAS program.(23) We found that the minima of energies of intersubunit interactions support two alternate positions consistent with their transport properties. Thus, for GlpT, a "tilt" of 9 degrees -10 degrees rotation had the most favorable energetics of electrostatic interaction between the two halves of the transporter; moreover, this confirmation was sufficient to suggest transport of the ligand across the membrane. We conducted steered molecular dynamics simulations of the GlpT-ligand system to explore how glycerol-3-phosphate would be handled by the "tilted" structure, and obtained results generally consistent with experimental mutagenesis data. While biochemical data remain most consistent with a single-site alternating access model, our results raise the possibility that, while the

  1. A dynamical stabilizer in the climate system: a mechanism suggested by a simple model

    Science.gov (United States)

    Bates, J. R.

    1999-05-01

    involve inter-zone coupling and have coefficients dependent on the values of the equilibrium fluxes and the sensitivity of the angular momentum transport. Analytical solutions for the perturbations are obtained. These provide criteria for the stability of the equilibrium climate. If the evaporative feedback on SST perturbations is omitted, the equilibrium climate is unstable due to the influence of the water vapour/infrared radiative feedback, which dominates over the effects of the sensible heat and ocean heat transport feedbacks. The inclusion of evaporation gives a negative feedback which is of sufficient strength to stabilize the system. The stabilizing mechanism involves wind and humidity factors in the evaporative fluxes that are of comparable magnitude. Both factors involve the angular momentum transport. In including angular momentum and calculating the surface fluxes explicitly, the model presented here differs from the many simple climate models based on the Budyko Sellers formulation. In that formulation, an atmospheric energy balance equation is used to eliminate surface fluxes in favour of top-of-the-atmosphere radiative fluxes and meridional atmospheric energy transports. In the resulting models, infrared radiation appears as a stabilizing influence on SST perturbations and the dynamical stabilizing mechanism found here cannot be identified.

  2. Mathematical modeling of sustainable synaptogenesis by repetitive stimuli suggests signaling mechanisms in vivo.

    Directory of Open Access Journals (Sweden)

    Hiromu Takizawa

    Full Text Available The mechanisms of long-term synaptic maintenance are a key component to understanding the mechanism of long-term memory. From biological experiments, a hypothesis arose that repetitive stimuli with appropriate intervals are essential to maintain new synapses for periods of longer than a few days. We successfully reproduce the time-course of relative numbers of synapses with our mathematical model in the same conditions as biological experiments, which used Adenosine-3', 5'-cyclic monophosphorothioate, Sp-isomer (Sp-cAMPS as external stimuli. We also reproduce synaptic maintenance responsiveness to intervals of Sp-cAMPS treatment accompanied by PKA activation. The model suggests a possible mechanism of sustainable synaptogenesis which consists of two steps. First, the signal transduction from an external stimulus triggers the synthesis of a new signaling protein. Second, the new signaling protein is required for the next signal transduction with the same stimuli. As a result, the network component is modified from the first network, and a different signal is transferred which triggers the synthesis of another new signaling molecule. We refer to this hypothetical mechanism as network succession. We build our model on the basis of two hypotheses: (1 a multi-step network succession induces downregulation of SSH and COFILIN gene expression, which triggers the production of stable F-actin; (2 the formation of a complex of stable F-actin with Drebrin at PSD is the critical mechanism to achieve long-term synaptic maintenance. Our simulation shows that a three-step network succession is sufficient to reproduce sustainable synapses for a period longer than 14 days. When we change the network structure to a single step network, the model fails to follow the exact condition of repetitive signals to reproduce a sufficient number of synapses. Another advantage of the three-step network succession is that this system indicates a greater tolerance of parameter

  3. Coalescent Modelling Suggests Recent Secondary-Contact of Cryptic Penguin Species.

    Science.gov (United States)

    Grosser, Stefanie; Burridge, Christopher P; Peucker, Amanda J; Waters, Jonathan M

    2015-01-01

    Molecular genetic analyses present powerful tools for elucidating demographic and biogeographic histories of taxa. Here we present genetic evidence showing a dynamic history for two cryptic lineages within Eudyptula, the world's smallest penguin. Specifically, we use a suite of genetic markers to reveal that two congeneric taxa ('Australia' and 'New Zealand') co-occur in southern New Zealand, with only low levels of hybridization. Coalescent modelling suggests that the Australian little penguin only recently expanded into southern New Zealand. Analyses conducted under time-dependent molecular evolutionary rates lend support to the hypothesis of recent anthropogenic turnover, consistent with shifts detected in several other New Zealand coastal vertebrate taxa. This apparent turnover event highlights the dynamic nature of the region's coastal ecosystem.

  4. Microarray and bioinformatic analyses suggest models for carbon metabolism in the autotroph Acidithiobacillus ferrooxidans

    Energy Technology Data Exchange (ETDEWEB)

    C. Appia-ayme; R. Quatrini; Y. Denis; F. Denizot; S. Silver; F. Roberto; F. Veloso; J. Valdes; J. P. Cardenas; M. Esparza; O. Orellana; E. Jedlicki; V. Bonnefoy; D. Holmes

    2006-09-01

    Acidithiobacillus ferrooxidans is a chemolithoautotrophic bacterium that uses iron or sulfur as an energy and electron source. Bioinformatic analysis was used to identify putative genes and potential metabolic pathways involved in CO2 fixation, 2P-glycolate detoxification, carboxysome formation and glycogen utilization in At. ferrooxidans. Microarray transcript profiling was carried out to compare the relative expression of the predicted genes of these pathways when the microorganism was grown in the presence of iron versus sulfur. Several gene expression patterns were confirmed by real-time PCR. Genes for each of the above predicted pathways were found to be organized into discrete clusters. Clusters exhibited differential gene expression depending on the presence of iron or sulfur in the medium. Concordance of gene expression within each cluster, suggested that they are operons Most notably, clusters of genes predicted to be involved in CO2 fixation, carboxysome formation, 2P-glycolate detoxification and glycogen biosynthesis were up-regulated in sulfur medium, whereas genes involved in glycogen utilization were preferentially expressed in iron medium. These results can be explained in terms of models of gene regulation that suggest how A. ferrooxidans can adjust its central carbon management to respond to changing environmental conditions.

  5. A cervid vocal fold model suggests greater glottal efficiency in calling at high frequencies.

    Directory of Open Access Journals (Sweden)

    Ingo R Titze

    2010-08-01

    Full Text Available Male Rocky Mountain elk (Cervus elaphus nelsoni produce loud and high fundamental frequency bugles during the mating season, in contrast to the male European Red Deer (Cervus elaphus scoticus who produces loud and low fundamental frequency roaring calls. A critical step in understanding vocal communication is to relate sound complexity to anatomy and physiology in a causal manner. Experimentation at the sound source, often difficult in vivo in mammals, is simulated here by a finite element model of the larynx and a wave propagation model of the vocal tract, both based on the morphology and biomechanics of the elk. The model can produce a wide range of fundamental frequencies. Low fundamental frequencies require low vocal fold strain, but large lung pressure and large glottal flow if sound intensity level is to exceed 70 dB at 10 m distance. A high-frequency bugle requires both large muscular effort (to strain the vocal ligament and high lung pressure (to overcome phonation threshold pressure, but at least 10 dB more intensity level can be achieved. Glottal efficiency, the ration of radiated sound power to aerodynamic power at the glottis, is higher in elk, suggesting an advantage of high-pitched signaling. This advantage is based on two aspects; first, the lower airflow required for aerodynamic power and, second, an acoustic radiation advantage at higher frequencies. Both signal types are used by the respective males during the mating season and probably serve as honest signals. The two signal types relate differently to physical qualities of the sender. The low-frequency sound (Red Deer call relates to overall body size via a strong relationship between acoustic parameters and the size of vocal organs and body size. The high-frequency bugle may signal muscular strength and endurance, via a 'vocalizing at the edge' mechanism, for which efficiency is critical.

  6. Rate control management of atrial fibrillation: may a mathematical model suggest an ideal heart rate?

    Directory of Open Access Journals (Sweden)

    Matteo Anselmino

    Full Text Available Despite the routine prescription of rate control therapy for atrial fibrillation (AF, clinical evidence demonstrating a heart rate target is lacking. Aim of the present study was to run a mathematical model simulating AF episodes with a different heart rate (HR to predict hemodynamic parameters for each situation.The lumped model, representing the pumping heart together with systemic and pulmonary circuits, was run to simulate AF with HR of 50, 70, 90, 110 and 130 bpm, respectively.Left ventricular pressure increased by 57%, from 33.92±37.56 mmHg to 53.15±47.56 mmHg, and mean systemic arterial pressure increased by 27%, from 82.66±14.04 mmHg to 105.3±7.6 mmHg, at the 50 and 130 bpm simulations, respectively. Stroke volume (from 77.45±8.50 to 39.09±8.08 mL, ejection fraction (from 61.10±4.40 to 39.32±5.42% and stroke work (SW, from 0.88±0.04 to 0.58±0.09 J decreased by 50, 36 and 34%, at the 50 and 130 bpm simulations, respectively. In addition, oxygen consumption indexes (rate pressure product - RPP, tension time index per minute - TTI/min, and pressure volume area per minute - PVA/min increased from the 50 to the 130 bpm simulation, respectively, by 186% (from 5598±1939 to 15995±3219 mmHg/min, 56% (from 2094±265 to 3257±301 mmHg s/min and 102% (from 57.99±17.90 to 117.4±26.0 J/min. In fact, left ventricular efficiency (SW/PVA decreased from 80.91±2.91% at 50 bpm to 66.43±3.72% at the 130 bpm HR simulation.Awaiting compulsory direct clinical evidences, the present mathematical model suggests that lower HRs during permanent AF relates to improved hemodynamic parameters, cardiac efficiency, and lower oxygen consumption.

  7. Rate control management of atrial fibrillation: may a mathematical model suggest an ideal heart rate?

    Science.gov (United States)

    Anselmino, Matteo; Scarsoglio, Stefania; Camporeale, Carlo; Saglietto, Andrea; Gaita, Fiorenzo; Ridolfi, Luca

    2015-01-01

    Despite the routine prescription of rate control therapy for atrial fibrillation (AF), clinical evidence demonstrating a heart rate target is lacking. Aim of the present study was to run a mathematical model simulating AF episodes with a different heart rate (HR) to predict hemodynamic parameters for each situation. The lumped model, representing the pumping heart together with systemic and pulmonary circuits, was run to simulate AF with HR of 50, 70, 90, 110 and 130 bpm, respectively. Left ventricular pressure increased by 57%, from 33.92±37.56 mmHg to 53.15±47.56 mmHg, and mean systemic arterial pressure increased by 27%, from 82.66±14.04 mmHg to 105.3±7.6 mmHg, at the 50 and 130 bpm simulations, respectively. Stroke volume (from 77.45±8.50 to 39.09±8.08 mL), ejection fraction (from 61.10±4.40 to 39.32±5.42%) and stroke work (SW, from 0.88±0.04 to 0.58±0.09 J) decreased by 50, 36 and 34%, at the 50 and 130 bpm simulations, respectively. In addition, oxygen consumption indexes (rate pressure product - RPP, tension time index per minute - TTI/min, and pressure volume area per minute - PVA/min) increased from the 50 to the 130 bpm simulation, respectively, by 186% (from 5598±1939 to 15995±3219 mmHg/min), 56% (from 2094±265 to 3257±301 mmHg s/min) and 102% (from 57.99±17.90 to 117.4±26.0 J/min). In fact, left ventricular efficiency (SW/PVA) decreased from 80.91±2.91% at 50 bpm to 66.43±3.72% at the 130 bpm HR simulation. Awaiting compulsory direct clinical evidences, the present mathematical model suggests that lower HRs during permanent AF relates to improved hemodynamic parameters, cardiac efficiency, and lower oxygen consumption.

  8. Radiolabelled somatostatin analogue treatment in gastroenteropancreatic neuroendocrine tumours: factors associated with response and suggestions for therapeutic sequence

    Energy Technology Data Exchange (ETDEWEB)

    Campana, Davide; Nori, Francesca; Cacciari, Giulia; Tomassetti, Paola [University of Bologna, Department of Medical and Surgical Sciences, Bologna (Italy); Capurso, Gabriele; Panzuto, Francesco; Delle Fave, Gianfranco [University of Rome, Digestive and Liver Disease Unit, Rome (Italy); Partelli, Stefano [Sacro Cuore Don Calabria Hospital, Department of Surgery, Negrar (Italy); University of Verona, Department of Surgery, Verona (Italy); Universita Politecnica delle Marche, Pancreas Surgical Unit, Ancona (Italy); Tamburrino, Domenico; Falconi, Massimo [University of Verona, Department of Surgery, Verona (Italy); Universita Politecnica delle Marche, Pancreas Surgical Unit, Ancona (Italy)

    2013-08-15

    Peptide receptor radionuclide therapy (PRRT) is a relatively new treatment modality for patients with unresectable or metastatic gastroenteropancreatic neuroendocrine tumours (GEP NETs). The aim of this study was to determine the time to progression of patients treated with PRRT and to identify the prognostic factors related to treatment response. Patients with sporadic GEP NETs prospectively treated with PRRT were retrospectively analysed. The primary end point was progression-free survival (PFS). A total of 69 patients (37 men and 32 women; 45 with pancreatic and 24 with gastrointestinal lesion; 22 NET G1 and 41 NET G2) were treated with {sup 90}Y or {sup 177}Lu. The objective response rate was 27.5 % (partial response, PR), while 50.7 % had stable disease and 23.2 % had progressive disease. Significant differences in PFS were observed in relationship to the stage of the disease (44 months for stage III, 23 months for stage IV), the evidence of a PR 6 months after the end of the PRRT (39 months in patients with a PR, 22 months in patients without a PR) and previous transarterial chemoembolization (TACE, yes 13 months vs no 31 months). Stage IV, NET G2 and previous TACE were found to be significant factors for tumour progression at multivariate analysis. Low tumour burden and a low proliferation index represent independent prognostic factors for long PFS, while previous chemoembolization techniques represent independent prognostic factors for early tumour progression and shorter PFS. Our data suggest that chemoembolization techniques to reduce the hepatic tumour burden should be avoided. (orig.)

  9. Genomic survey, gene expression analysis and structural modeling suggest diverse roles of DNA methyltransferases in legumes.

    Directory of Open Access Journals (Sweden)

    Rohini Garg

    Full Text Available DNA methylation plays a crucial role in development through inheritable gene silencing. Plants possess three types of DNA methyltransferases (MTases, namely Methyltransferase (MET, Chromomethylase (CMT and Domains Rearranged Methyltransferase (DRM, which maintain methylation at CG, CHG and CHH sites. DNA MTases have not been studied in legumes so far. Here, we report the identification and analysis of putative DNA MTases in five legumes, including chickpea, soybean, pigeonpea, Medicago and Lotus. MTases in legumes could be classified in known MET, CMT, DRM and DNA nucleotide methyltransferases (DNMT2 subfamilies based on their domain organization. First three MTases represent DNA MTases, whereas DNMT2 represents a transfer RNA (tRNA MTase. Structural comparison of all the MTases in plants with known MTases in mammalian and plant systems have been reported to assign structural features in context of biological functions of these proteins. The structure analysis clearly specified regions crucial for protein-protein interactions and regions important for nucleosome binding in various domains of CMT and MET proteins. In addition, structural model of DRM suggested that circular permutation of motifs does not have any effect on overall structure of DNA methyltransferase domain. These results provide valuable insights into role of various domains in molecular recognition and should facilitate mechanistic understanding of their function in mediating specific methylation patterns. Further, the comprehensive gene expression analyses of MTases in legumes provided evidence of their role in various developmental processes throughout the plant life cycle and response to various abiotic stresses. Overall, our study will be very helpful in establishing the specific functions of DNA MTases in legumes.

  10. Hindering factors and suggestions related to organ donation decisions: perspective of the Taiwan Ali-Shan Tsou aboriginal tribe.

    Science.gov (United States)

    Chen, A N; Chen, K F; Chang, P C; Shih, F Jong; Chen, C R; Shih, F-Jin; Huang, C-Y

    2014-05-01

    Ali-San Tsou (AST) is one of leading aboriginal tribes in Taiwan with traditional godly beliefs related to life and death. Lacking related knowledge, health professionals (HPs) often failed to help them reach good dying or organ donation (OD). This study aimed to explore hindering factors and suggestions related to OD for good dying from Taiwan AST's own perspective. An explorative qualitative design was employed using a purposive sample of the AST tribes from Taiwan. Data were collected with AST residents by face-to-face interviews and analyzed by content analysis. Thirty AST residents (16 females and 14 males) with ages ranging from 28 to 78 (mean, 54.5) years completed interviews. Of them, 85% reported various diseases. In this study 73% were Catholics and Christians, 17% held traditional godly believes, and 10% had no religious affiliation. Eight hindering factors were reported: (1) limited information about organs and OD; (2) no qualified organs for donation; (3) worry about lack of forgiveness by ancestors; (4) tribe elders who might not accept concept of OD; (5) intact bodies were required at home during spirit-companion rituals; (6) earth burial with intact bodies was preferred; (7) bodies due to accidental and bad death were impermissible for OD; and (8) worry about possession by the donor's spirit. Seven suggestions were also reported for HPs to enhance AST's OD decisions: (1) starting with friendship and a caring relationship; (2) providing spiritual support from reverent religions; (3) stressing good deeds and honoring tribe folks by OD; (4) avoiding accidental/bad death; (5) providing relevant modern medical knowledge of human organs and OD; (6) introducing OD as part of a good-dying care plan; and (7) demonstrating a respectful discussion mindset about OD. Eight hindering factors and 7 types of suggestions for enhancing AST aboriginal people's OD decisions were first explored in this project. In the future, HPs are encouraged to invite AST to share

  11. An innovation resistance factor model

    Directory of Open Access Journals (Sweden)

    Siti Salwa Mohd Ishak

    2016-09-01

    Full Text Available The process and implementation strategy of information technology in construction is generally considered through the limiting prism of theoretical contexts generated from innovation diffusion and acceptance. This research argues that more attention should be given to understanding the positive effects of resistance. The study develops a theoretical framing for the Integrated Resistance Factor Model (IRFM. The framing uses a combination of diffusion of innovation theory, technology acceptance model and social network perspective. The model is tested to identify the most significant resistance factors using Partial Least Square (PLS technique. All constructs proposed in the model are found to be significant, valid and consistent with the theoretical framework. IRFM is shown to be an effective and appropriate model of user resistance factors. The most critical factors to influence technology resistance in the online project information management system (OPIMS context are: support from leaders and peers, complexity of the technology, compatibility with key work practices; and pre-trial of the technology before it is actually deployed. The study provides a new model for further research in technology innovation specific to the construction industry.

  12. Conceptual Models in Health Informatics Research: A Literature Review and Suggestions for Development.

    Science.gov (United States)

    Gray, Kathleen; Sockolow, Paulina

    2016-02-24

    Contributing to health informatics research means using conceptual models that are integrative and explain the research in terms of the two broad domains of health science and information science. However, it can be hard for novice health informatics researchers to find exemplars and guidelines in working with integrative conceptual models. The aim of this paper is to support the use of integrative conceptual models in research on information and communication technologies in the health sector, and to encourage discussion of these conceptual models in scholarly forums. A two-part method was used to summarize and structure ideas about how to work effectively with conceptual models in health informatics research that included (1) a selective review and summary of the literature of conceptual models; and (2) the construction of a step-by-step approach to developing a conceptual model. The seven-step methodology for developing conceptual models in health informatics research explained in this paper involves (1) acknowledging the limitations of health science and information science conceptual models; (2) giving a rationale for one's choice of integrative conceptual model; (3) explicating a conceptual model verbally and graphically; (4) seeking feedback about the conceptual model from stakeholders in both the health science and information science domains; (5) aligning a conceptual model with an appropriate research plan; (6) adapting a conceptual model in response to new knowledge over time; and (7) disseminating conceptual models in scholarly and scientific forums. Making explicit the conceptual model that underpins a health informatics research project can contribute to increasing the number of well-formed and strongly grounded health informatics research projects. This explication has distinct benefits for researchers in training, research teams, and researchers and practitioners in information, health, and other disciplines.

  13. A multi-scale energy demand model suggests sharing market risks with intelligent energy cooperatives

    NARCIS (Netherlands)

    G. Methenitis (Georgios); M. Kaisers (Michael); J.A. La Poutré (Han)

    2015-01-01

    textabstractIn this paper, we propose a multi-scale model of energy demand that is consistent with observations at a macro scale, in our use-case standard load profiles for (residential) electric loads. We employ the model to study incentives to assume the risk of volatile market prices for

  14. Predictor Relationships between Values Held by Married Individuals, Resilience and Conflict Resolution Styles: A Model Suggestion

    Science.gov (United States)

    Tosun, Fatma; Dilmac, Bulent

    2015-01-01

    The aim of the present research is to reveal the predictor relationships between the values held by married individuals, resilience and conflict resolution styles. The research adopts a relational screening model that is a sub-type of the general screening model. The sample of the research consists of 375 married individuals, of which 173 are…

  15. Variably hungry caterpillars: predictive models and foliar chemistry suggest how to eat a rainforest

    Czech Academy of Sciences Publication Activity Database

    Segar, Simon Tristram; Volf, Martin; Isua, B.; Sisol, M.; Redmond, Conor; Rosati, M. E.; Gewa, B.; Molem, K.; Dahl, Chris; Holloway, J. D.; Basset, Yves; Miller, S. E.; Weiblen, G. D.; Salminen, J.-P.; Novotný, Vojtěch

    2017-01-01

    Roč. 284, č. 1866 (2017), č. článku 20171803. ISSN 0962-8452 R&D Projects: GA ČR(CZ) GA17-23862S; GA ČR GA15-24571S EU Projects: European Commission(XE) 669609 - Diversity6continents Grant - others:European Social Fund(CZ) CZ.1.07/2.3.00/30.0006 Institutional support: RVO:60077344 Keywords : biodiversity * food webs * Geometridae Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 4.940, year: 2016 http://rspb.royalsocietypublishing.org/content/royprsb/284/1866/20171803.full.pdf

  16. A Latent Growth Model Suggests that Empathy of Medical Students Does Not Decline over Time

    Science.gov (United States)

    Costa, Patrício; Magalhães, Eunice; Costa, Manuel João

    2013-01-01

    Empathy is a relevant attribute in the context of patient care. However, a decline in empathy throughout medical education has been reported in North-American medical schools, particularly, in the transition to clinical training. The present study aims to longitudinally model empathy during medical school at three time points: at the entrance,…

  17. Comparing Satellite Rainfall Estimates with Rain-Gauge Data: Optimal Strategies Suggested by a Spectral Model

    Science.gov (United States)

    Bell, Thomas L.; Kundu, Prasun K.; Lau, William K. M. (Technical Monitor)

    2002-01-01

    Validation of satellite remote-sensing methods for estimating rainfall against rain-gauge data is attractive because of the direct nature of the rain-gauge measurements. Comparisons of satellite estimates to rain-gauge data are difficult, however, because of the extreme variability of rain and the fact that satellites view large areas over a short time while rain gauges monitor small areas continuously. In this paper, a statistical model of rainfall variability developed for studies of sampling error in averages of satellite data is used to examine the impact of spatial and temporal averaging of satellite and gauge data on intercomparison results. The model parameters were derived from radar observations of rain, but the model appears to capture many of the characteristics of rain-gauge data as well. The model predicts that many months of data from areas containing a few gauges are required to validate satellite estimates over the areas, and that the areas should be of the order of several hundred km in diameter. Over gauge arrays of sufficiently high density, the optimal areas and averaging times are reduced. The possibility of using time-weighted averages of gauge data is explored.

  18. Factors Affecting a Recently Purchased Handgun’s Risk for Use in Crime under Circumstances That Suggest Gun Trafficking

    Science.gov (United States)

    Wintemute, Garen J.; Webster, Daniel W.

    2010-01-01

    While many handguns are used in crime each year in the USA, most are not. We conducted this study to identify factors present at the time of a handgun’s most recent retail sale that were associated with its subsequent use in crime under circumstances suggesting that the handgun had been trafficked—purchased with the intent of diverting it to criminal use. Handguns acquired in multiple-gun purchases were of particular interest. Using data for 180,321 handguns purchased from federally licensed retailers in California in 1996, we studied attributes of the handguns, the retailers selling them, the purchasers, and the sales transactions. Our outcome measure was a handgun’s recovery by a police agency, followed by a gun ownership trace, conducted by the Bureau of Alcohol, Tobacco, Firearms and Explosives, that determined (a) that the recovery had occurred within 3 years of the handgun’s most recent purchase from a licensed retailer and (b) that the person who possessed the gun when it was recovered by police was not its most recent purchaser. Altogether, 722 handguns were recovered and had trace results that met the additional criteria. Handguns acquired in multiple-gun, same-day transactions were more likely to be traced than were single-purchase handguns (odds ratio [OR] 1.33, 95% confidence intervals [CI] 1.08 to 1.63). This was not the case for multiple-purchase handguns defined more broadly as multiple handguns purchased by one individual over any 30-day period as used in “one-gun-a-month” laws. Bivariate regressions indicated increased risk of a handgun being traced when it sold new for $150 or less (OR 4.28, 95% CI 3.59 to 5.11) or had been purchased by a woman (OR 2.02, 95% CI 1.62 to 2.52). Handguns sold by retailers who also had a relatively high proportion (≥2%) of purchases denied because the prospective purchasers were prohibited from owning firearms were more likely to be traced than were those sold by other retailers (OR 4.09, 95% CI 3.39 to

  19. Factors affecting a recently purchased handgun's risk for use in crime under circumstances that suggest gun trafficking.

    Science.gov (United States)

    Wright, Mona A; Wintemute, Garen J; Webster, Daniel W

    2010-05-01

    While many handguns are used in crime each year in the USA, most are not. We conducted this study to identify factors present at the time of a handgun's most recent retail sale that were associated with its subsequent use in crime under circumstances suggesting that the handgun had been trafficked--purchased with the intent of diverting it to criminal use. Handguns acquired in multiple-gun purchases were of particular interest. Using data for 180,321 handguns purchased from federally licensed retailers in California in 1996, we studied attributes of the handguns, the retailers selling them, the purchasers, and the sales transactions. Our outcome measure was a handgun's recovery by a police agency, followed by a gun ownership trace, conducted by the Bureau of Alcohol, Tobacco, Firearms and Explosives, that determined (a) that the recovery had occurred within 3 years of the handgun's most recent purchase from a licensed retailer and (b) that the person who possessed the gun when it was recovered by police was not its most recent purchaser. Altogether, 722 handguns were recovered and had trace results that met the additional criteria. Handguns acquired in multiple-gun, same-day transactions were more likely to be traced than were single-purchase handguns (odds ratio [OR] 1.33, 95% confidence intervals [CI] 1.08 to 1.63). This was not the case for multiple-purchase handguns defined more broadly as multiple handguns purchased by one individual over any 30-day period as used in "one-gun-a-month" laws. Bivariate regressions indicated increased risk of a handgun being traced when it sold new for $150 or less (OR 4.28, 95% CI 3.59 to 5.11) or had been purchased by a woman (OR 2.02, 95% CI 1.62 to 2.52). Handguns sold by retailers who also had a relatively high proportion (>or=2%) of purchases denied because the prospective purchasers were prohibited from owning firearms were more likely to be traced than were those sold by other retailers (OR 4.09, 95% CI 3.39 to 4

  20. A suggested model for physical examination and conservative treatment of athletic pubalgia.

    Science.gov (United States)

    Hegedus, Eric J; Stern, Ben; Reiman, Michael P; Tarara, Dan; Wright, Alexis A

    2013-02-01

    Athletic pubalgia (AP) is a chronic debilitating syndrome that affects many athletes. As a syndrome, AP is difficult to diagnose both with clinical examination and imaging. AP is also a challenge for conservative intervention with randomized controlled trials showing mixed success rates. In other syndromes where clinical diagnosis and conservative treatment have been less than clear, a paradigm has been suggested as a framework for clinical decision making. To propose a new clinical diagnostic and treatment paradigm for the conservative management of AP. Relevant studies were viewed with regard to diagnosis and intervention and where a gap in evidence existed, clinical expertise was used to fill that gap and duly noted. A new paradigm is proposed to assist with clinical diagnosis and non-surgical intervention in patients suffering with AP. The level of evidence supporting this paradigm, according to the SORT taxonomy, is primarily level 2B. Further testing is warranted but following the suggested paradigm should lead to a clearer diagnosis of AP and allow more meaningful research into homogeneous patient populations within the AP diagnostic cluster. Strength-of-Recommendation Taxonomy (SORT): 2B. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. The Nature of Scatter at the DARHT Facility and Suggestions for Improved Modeling of DARHT Facility

    Energy Technology Data Exchange (ETDEWEB)

    Morneau, Rachel Anne [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Klasky, Marc Louis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-09

    The U.S. Stockpile Stewardship Program [1] is designed to sustain and evaluate the nuclear weapons stockpile while foregoing underground nuclear tests. The maintenance of a smaller, aging U.S. nuclear weapons stockpile without underground testing requires complex computer calculations [14]. These calculations in turn need to be verified and benchmarked [14]. A wide range of research facilities have been used to test and evaluate nuclear weapons while respecting the Comprehensive Nuclear Test-Ban Treaty (CTBT) [2]. Some of these facilities include the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, the Z machine at Sandia National Laboratories, and the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory. This research will focus largely on DARHT (although some information from Cygnus and the Los Alamos Microtron may be used in this research) by modeling it and comparing to experimental data. DARHT is an electron accelerator that employs high-energy flash x-ray sources for imaging hydro-tests. This research proposes to address some of the issues crucial to understanding DARHT Axis II and the analysis of the radiographic images produced. Primarily, the nature of scatter at DARHT will be modeled and verified with experimental data. It will then be shown that certain design decisions can be made to optimize the scatter field for hydrotest experiments. Spectral effects will be briefly explored to determine if there is any considerable effect on the density reconstruction caused by changes in the energy spectrum caused by target changes. Finally, a generalized scatter model will be made using results from MCNP that can be convolved with the direct transmission of an object to simulate the scatter of that object at the detector plane. The region in which with this scatter model is appropriate will be explored.

  2. A normalization model suggests that attention changes the weighting of inputs between visual areas.

    Science.gov (United States)

    Ruff, Douglas A; Cohen, Marlene R

    2017-05-16

    Models of divisive normalization can explain the trial-averaged responses of neurons in sensory, association, and motor areas under a wide range of conditions, including how visual attention changes the gains of neurons in visual cortex. Attention, like other modulatory processes, is also associated with changes in the extent to which pairs of neurons share trial-to-trial variability. We showed recently that in addition to decreasing correlations between similarly tuned neurons within the same visual area, attention increases correlations between neurons in primary visual cortex (V1) and the middle temporal area (MT) and that an extension of a classic normalization model can account for this correlation increase. One of the benefits of having a descriptive model that can account for many physiological observations is that it can be used to probe the mechanisms underlying processes such as attention. Here, we use electrical microstimulation in V1 paired with recording in MT to provide causal evidence that the relationship between V1 and MT activity is nonlinear and is well described by divisive normalization. We then use the normalization model and recording and microstimulation experiments to show that the attention dependence of V1-MT correlations is better explained by a mechanism in which attention changes the weights of connections between V1 and MT than by a mechanism that modulates responses in either area. Our study shows that normalization can explain interactions between neurons in different areas and provides a framework for using multiarea recording and stimulation to probe the neural mechanisms underlying neuronal computations.

  3. Retrospective analysis of the quality of reports by author-suggested and non-author-suggested reviewers in journals operating on open or single-blind peer review models.

    Science.gov (United States)

    Kowalczuk, Maria K; Dudbridge, Frank; Nanda, Shreeya; Harriman, Stephanie L; Patel, Jigisha; Moylan, Elizabeth C

    2015-09-29

    To assess whether reports from reviewers recommended by authors show a bias in quality and recommendation for editorial decision, compared with reviewers suggested by other parties, and whether reviewer reports for journals operating on open or single-blind peer review models differ with regard to report quality and reviewer recommendations. Retrospective analysis of the quality of reviewer reports using an established Review Quality Instrument, and analysis of reviewer recommendations and author satisfaction surveys. BioMed Central biology and medical journals. BMC Infectious Diseases and BMC Microbiology are similar in size, rejection rates, impact factors and editorial processes, but the former uses open peer review while the latter uses single-blind peer review. The Journal of Inflammation has operated under both peer review models. Two hundred reviewer reports submitted to BMC Infectious Diseases, 200 reviewer reports submitted to BMC Microbiology and 400 reviewer reports submitted to the Journal of Inflammation. For each journal, author-suggested reviewers provided reports of comparable quality to non-author-suggested reviewers, but were significantly more likely to recommend acceptance, irrespective of the peer review model (previewer reports measured by the Review Quality Instrument was 5% higher than for BMC Microbiology (p=0.042). For the Journal of Inflammation, the quality of reports was the same irrespective of the peer review model used. Reviewers suggested by authors provide reports of comparable quality to non-author-suggested reviewers, but are significantly more likely to recommend acceptance. Open peer review reports for BMC Infectious Diseases were of higher quality than single-blind reports for BMC Microbiology. There was no difference in quality of peer review in the Journal of Inflammation under open peer review compared with single blind. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a

  4. Hypothalamus transcriptome profile suggests an anorexia-cachexia syndrome in the anx/anx mouse model.

    Science.gov (United States)

    Mercader, Josep Maria; Lozano, Juan José; Sumoy, Lauro; Dierssen, Mara; Visa, Joana; Gratacòs, Mònica; Estivill, Xavier

    2008-11-12

    The anx/anx mouse displays poor appetite and lean appearance and is considered a good model for the study of anorexia nervosa. To identify new genes involved in feeding behavior and body weight regulation we performed an expression profiling in the hypothalamus of the anx/anx mice. Using commercial microarrays we detected 156 differentially expressed genes and validated 92 of those using TaqMan low-density arrays. The expression of a set of 87 candidate genes selected based on literature evidences was also quantified by TaqMan low-density arrays. Our results showed enrichment in deregulated genes involved in cell death, cell morphology, and cancer, as well as an alteration of several signaling circuits involved in energy balance including neuropeptide Y and melanocortin signaling. The expression profile along with the phenotype led us to conclude that anx/anx mice resemble the anorexia-cachexia syndrome typically observed in cancer, infection with human immunodeficiency virus or chronic diseases, rather than starvation, and that anx/anx mice could be considered a good model for the treatment and investigation of this condition.

  5. Spectroscopic imaging of the pilocarpine model of human epilepsy suggests that early NAA reduction predicts epilepsy.

    Science.gov (United States)

    Gomes, W A; Lado, F A; de Lanerolle, N C; Takahashi, K; Pan, C; Hetherington, H P

    2007-08-01

    Reduced hippocampal N-acetyl aspartate (NAA) is commonly observed in patients with advanced, chronic temporal lobe epilepsy (TLE). It is unclear, however, whether an NAA deficit is also present during the clinically quiescent latent period that characterizes early TLE. This question has important implications for the use of MR spectroscopic imaging (MRSI) in the early identification of patients at risk for TLE. To determine whether NAA is diminished during the latent period, we obtained high-resolution (1)H spectroscopic imaging during the latent period of the rat pilocarpine model of human TLE. We used actively detuneable surface reception and volume transmission coils to enhance sensitivity and a semiautomated voxel shifting method to accurately position voxels within the hippocampi. During the latent period, 2 and 7 d following pilocarpine treatment, hippocampal NAA was significantly reduced by 27.5 +/- 6.9% (P NAA deficit is not due to neuron loss and therefore likely represents metabolic impairment of hippocampal neurons during the latent phase. Therefore, spectroscopic imaging provides an early marker for metabolic dysfunction in this model of TLE.

  6. Active tension network model suggests an exotic mechanical state realized in epithelial tissues

    Science.gov (United States)

    Noll, Nicholas; Mani, Madhav; Heemskerk, Idse; Streichan, Sebastian J.; Shraiman, Boris I.

    2017-12-01

    Mechanical interactions play a crucial role in epithelial morphogenesis, yet understanding the complex mechanisms through which stress and deformation affect cell behaviour remains an open problem. Here we formulate and analyse the active tension network (ATN) model, which assumes that the mechanical balance of cells within a tissue is dominated by cortical tension and introduces tension-dependent active remodelling of the cortex. We find that ATNs exhibit unusual mechanical properties. Specifically, an ATN behaves as a fluid at short times, but at long times supports external tension like a solid. Furthermore, an ATN has an extensively degenerate equilibrium mechanical state associated with a discrete conformal--`isogonal'--deformation of cells. The ATN model predicts a constraint on equilibrium cell geometries, which we demonstrate to approximately hold in certain epithelial tissues. We further show that isogonal modes are observed in the fruit fly embryo, accounting for the striking variability of apical areas of ventral cells and helping understand the early phase of gastrulation. Living matter realizes new and exotic mechanical states, the study of which helps to understand biological phenomena.

  7. Quantitative modeling of clinical, cellular, and extracellular matrix variables suggest prognostic indicators in cancer: a model in neuroblastoma.

    Science.gov (United States)

    Tadeo, Irene; Piqueras, Marta; Montaner, David; Villamón, Eva; Berbegall, Ana P; Cañete, Adela; Navarro, Samuel; Noguera, Rosa

    2014-02-01

    Risk classification and treatment stratification for cancer patients is restricted by our incomplete picture of the complex and unknown interactions between the patient's organism and tumor tissues (transformed cells supported by tumor stroma). Moreover, all clinical factors and laboratory studies used to indicate treatment effectiveness and outcomes are by their nature a simplification of the biological system of cancer, and cannot yet incorporate all possible prognostic indicators. A multiparametric analysis on 184 tumor cylinders was performed. To highlight the benefit of integrating digitized medical imaging into this field, we present the results of computational studies carried out on quantitative measurements, taken from stromal and cancer cells and various extracellular matrix fibers interpenetrated by glycosaminoglycans, and eight current approaches to risk stratification systems in patients with primary and nonprimary neuroblastoma. New tumor tissue indicators from both fields, the cellular and the extracellular elements, emerge as reliable prognostic markers for risk stratification and could be used as molecular targets of specific therapies. The key to dealing with personalized therapy lies in the mathematical modeling. The use of bioinformatics in patient-tumor-microenvironment data management allows a predictive model in neuroblastoma.

  8. Research Spotlight: Model suggests path to ending the ongoing Haitian cholera epidemic

    Science.gov (United States)

    Schultz, Colin

    2011-05-01

    Since early November 2010 a deadly cholera epidemic has been spreading across the Caribbean nation of Haiti, killing thousands of people and infecting hundreds of thousands. While infection rates are being actively monitored, health organizations have been left without a clear understanding of exactly how the disease has spread across Haiti. Cholera can spread through exposure to contaminated water, and the disease travels over long distances if an infected individual moves around the country. Using representations of these two predominant dispersion mechanisms, along with information on the size of the susceptible population, the number of infected individuals, and the aquatic concentration of the cholera-causing bacteria for more than 500 communities, Bertuzzo et al. designed a model that was able to accurately reproduce the progression of the Haitian cholera epidemic. (Geophysical Research Letters, doi:10.1029/2011GL046823, 2011)

  9. Model of a Generic Natural Uranium Conversion Plant ? Suggested Measures to Strengthen International Safeguards

    Energy Technology Data Exchange (ETDEWEB)

    Raffo-Caiado, Ana Claudia [ORNL; Begovich, John M [ORNL; Ferrada, Juan J [ORNL

    2009-11-01

    This is the final report that closed a joint collaboration effort between DOE and the National Nuclear Energy Commission of Brazil (CNEN). In 2005, DOE and CNEN started a collaborative effort to evaluate measures that can strengthen the effectiveness of international safeguards at a natural uranium conversion plant (NUCP). The work was performed by DOE s Oak Ridge National Laboratory and CNEN. A generic model of a NUCP was developed and typical processing steps were defined. Advanced instrumentation and techniques for verification purposes were identified and investigated. The scope of the work was triggered by the International Atomic Energy Agency s 2003 revised policy concerning the starting point of safeguards at uranium conversion facilities. Prior to this policy only the final products of the uranium conversion plant were considered to be of composition and purity suitable for use in the nuclear fuel cycle and therefore, subject to the IAEA safeguards control. DOE and CNEN have explored options for implementing the IAEA policy, although Brazil understands that the new policy established by the IAEA is beyond the framework of the Quadripartite Agreement of which it is one of the parties, together with Argentina, the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) and the IAEA. Two technical papers on this subject were published at the 2005 and 2008 INMM Annual Meetings.

  10. A link between mitotic entry and membrane growth suggests a novel model for cell size control.

    Science.gov (United States)

    Anastasia, Steph D; Nguyen, Duy Linh; Thai, Vu; Meloy, Melissa; MacDonough, Tracy; Kellogg, Douglas R

    2012-04-02

    Addition of new membrane to the cell surface by membrane trafficking is necessary for cell growth. In this paper, we report that blocking membrane traffic causes a mitotic checkpoint arrest via Wee1-dependent inhibitory phosphorylation of Cdk1. Checkpoint signals are relayed by the Rho1 GTPase, protein kinase C (Pkc1), and a specific form of protein phosphatase 2A (PP2A(Cdc55)). Signaling via this pathway is dependent on membrane traffic and appears to increase gradually during polar bud growth. We hypothesize that delivery of vesicles to the site of bud growth generates a signal that is proportional to the extent of polarized membrane growth and that the strength of the signal is read by downstream components to determine when sufficient growth has occurred for initiation of mitosis. Growth-dependent signaling could explain how membrane growth is integrated with cell cycle progression. It could also control both cell size and morphogenesis, thereby reconciling divergent models for mitotic checkpoint function.

  11. Factors Influencing Nonabsolute Indications for Surgery in Patients With Lower Urinary Tract Symptoms Suggestive of Benign Prostatic Hyperplasia: Analysis Using Causal Bayesian Networks

    Directory of Open Access Journals (Sweden)

    Myong Kim

    2014-12-01

    Full Text Available Purpose To identify the factors affecting the surgical decisions of experienced physicians when treating patients with lower urinary tract symptoms that are suggestive of benign prostatic hyperplasia (LUTS/BPH. Methods Patients with LUTS/BPH treated by two physicians between October 2004 and August 2013 were included in this study. The causal Bayesian network (CBN model was used to analyze factors influencing the surgical decisions of physicians and the actual performance of surgery. The accuracies of the established CBN models were verified using linear regression (LR analysis. Results A total of 1,108 patients with LUTS/BPH were analyzed. The mean age and total prostate volume (TPV were 66.2 (±7.3, standard deviation years and 47.3 (±25.4 mL, respectively. Of the total 1,108 patients, 603 (54.4% were treated by physician A and 505 (45.6% were treated by physician B. Although surgery was recommended to 699 patients (63.1%, 589 (53.2% actually underwent surgery. Our CBN model showed that the TPV (R=0.432, treating physician (R=0.370, bladder outlet obstruction (BOO on urodynamic study (UDS (R=0.324, and International Prostate Symptom Score (IPSS question 3 (intermittency; R=0.141 were the factors directly influencing the surgical decision. The transition zone volume (R=0.396, treating physician (R=0.340, and BOO (R=0.300 directly affected the performance of surgery. Compared to the LR model, the area under the receiver operating characteristic curve of the CBN surgical decision model was slightly compromised (0.803 vs. 0.847, P<0.001, whereas that of the actual performance of surgery model was similar (0.801 vs. 0.820, P=0.063 to the LR model. Conclusions The TPV, treating physician, BOO on UDS, and the IPSS item of intermittency were factors that directly influenced decision-making in physicians treating patients with LUTS/BPH.

  12. Identifying the important factors in simulation models with many factors

    NARCIS (Netherlands)

    Bettonvil, B.; Kleijnen, J.P.C.

    1994-01-01

    Simulation models may have many parameters and input variables (together called factors), while only a few factors are really important (parsimony principle). For such models this paper presents an effective and efficient screening technique to identify and estimate those important factors. The

  13. Architecture of TAF11/TAF13/TBP complex suggests novel regulation properties of general transcription factor TFIID

    Czech Academy of Sciences Publication Activity Database

    Gupta, K.; Wastson, A.A.; Baptista, T.; Scheer, E.; Chambers, A.; Koehler, CH.; Zou, J.; Obong-Ebong, I.; Kandiah, E.; Temblador, A.; Round, A.; Forest, E.; Man, Petr; Bienisssek, Ch.; Laue, E.D.; Lemke, E.A.; Rappsilber, J.; Robinson, C.V.; Devys, D.; Tora, L.; Berger, I.

    2017-01-01

    Roč. 6, e30395 (2017), s. 1-31 ISSN 2050-084X Institutional support: RVO:61388971 Keywords : TATA-BINDING PROTEIN * RNA-POLYMERASE-II * CRYSTAL-STRUCTURE Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology Impact factor: 7.725, year: 2016

  14. Strong associations between national prevalence of various STIs suggests sexual network connectivity is a common underpinning risk factor.

    Science.gov (United States)

    Kenyon, Chris

    2017-10-12

    If national peak Human Immunodeficiency Virus (HIV) prevalence is positively associated with the prevalence of other sexually transmitted infections (STIs) from before or early on in the HIV epidemics this would suggest common underlying drivers. Pearson's correlations were calculated between the prevalence of seven STIs at a country-level: chlamydia, gonorrhoea, trichomoniasis, syphilis, bacterial vaginosis, herpes simplex virus-2 (HSV-2) and HIV. The prevalence of all the STIs was highest in the sub-Saharan African region excluding chlamydia. The prevalence of all seven STIs were positively correlated excluding chlamydia. The correlations were strongest for HIV-HSV-2 (r = 0.85, P < 0.0001) and HSV-2-trichomoniasis (r = 0.82, P < 0.0001). Our results of a generally positive association between the prevalences of a range of STIs suggests that higher prevalences were driven by common underlying determinants. We review different types of evidence which suggest that differential sexual connectivity is a plausible common determinant.

  15. A Parametric Factor Model of the Term Structure of Mortality

    DEFF Research Database (Denmark)

    Haldrup, Niels; Rosenskjold, Carsten Paysen T.

    The prototypical Lee-Carter mortality model is characterized by a single common time factor that loads differently across age groups. In this paper we propose a factor model for the term structure of mortality where multiple factors are designed to influence the age groups differently via...... on the loading functions, the factors are not designed to be orthogonal but can be dependent and can possibly cointegrate when the factors have unit roots. We suggest two estimation procedures similar to the estimation of the dynamic Nelson-Siegel term structure model. First, a two-step nonlinear least squares...... procedure based on cross-section regressions together with a separate model to estimate the dynamics of the factors. Second, we suggest a fully specified model estimated by maximum likelihood via the Kalman filter recursions after the model is put on state space form. We demonstrate the methodology for US...

  16. Mouse model for Usher syndrome: linkage mapping suggests homology to Usher type I reported at human chromosome 11p15.

    OpenAIRE

    Heckenlively, J R; Chang, B; Erway, L C; Peng, C; Hawes, N L; Hageman, G S; Roderick, T H

    1995-01-01

    Usher syndrome is a group of diseases with autosomal recessive inheritance, congenital hearing loss, and the development of retinitis pigmentosa, a progressive retinal degeneration characterized by night blindness and visual field loss over several decades. The causes of Usher syndrome are unknown and no animal models have been available for study. Four human gene sites have been reported, suggesting at least four separate forms of Usher syndrome. We report a mouse model of type I Usher syndr...

  17. Citation trend and suggestions for improvement of impact factor of Journal of Korean Therapeutic Radiology and Oncology

    International Nuclear Information System (INIS)

    Kim, Seong Hwan; Hwang, Seong Su; Ahn, Myeong Im; Jeong, So Na

    2006-01-01

    To analyze the recent citation trend and to find a way to improve impact factor (IF) of the Journal of Korean Therapeutic Radiology and Oncology (JKSTRO) by analysis of Korean Medical Citation index (KoMCI) citation data of JKSTRO and comparison with that of mean citation data of all journals enlisted on KoMCI (KoMCI journals) during 2000-2005. All citation data of entire journals enlisted on KoMCI and JKSTRO from 2000 to 2005 were obtained from KoMCI. The trend of total and annual number of published articles and reference citations, total citations and self-citations per paper, IF and impact factor excluding self-citations (ZIF) were described and compared on both KoMCI journals an JKSTRO. Annual number of published articles was decreased for 6 years on both KoMCI journals and JKSTRO (32% and 38% reduction rate). The number of Korean journal references per article is 1.6 papers of JKSTRO comparing to 2.0 papers on KoMCI journals. The percentage of Korean references/total references increased from 5.0% in 2000 to 7.7% in 2005 on JKSTRO and from 8.5% in 2000 to 10.1% on KoMCI journals. The number of total citations received/paper on JKSTRO (average 1.333) is smaller than that of KoMCI journals (average 1.694), there was an increased rate of 67% in 2005 comparing to 2000. The percentage of self-citations/total citations (average 72%) on JKSTRO is slightly higher than that of KoMCI journals (average 61%)/ IF of JKSTRO was gradually improved and 0.144, 0.125, 0.088, 0.107, 0.187 and 0.203 in 2000-2005 respectively. However, ZIF of JKSTRO is steadily decreased from 0.038 in 2000 to 0.013 in 2005 except 0.044 in 2004. IF of JKSTRO was slightly improved but had some innate problem of smaller number of citations received . To make JKSTRO as a highly cited journal, the awareness of academic status of JKSTRO and active participation of every member of JKSTRO including encouraging self-citations of papers published recent 2 years and submission of English written papers, and

  18. Preliminary Finnish Measures of Eating Competence Suggest Association with Health-Promoting Eating Patterns and Related Psychobehavioral Factors in 10–17 Year Old Adolescents

    Directory of Open Access Journals (Sweden)

    Tilles-Tirkkonen Tanja

    2015-05-01

    Full Text Available Eating competence is an attitudinal and behavioral concept, based on The Satter Eating Competence Model. In adults, it has been shown to be associated with a higher quality of diet. Eating competence or its association with the quality of diet has not been studied in adolescents. The aim of the current study was to explore the utility of using a preliminary Finnish translation of the ecSI 2.0 for evaluating presumed eating competence and its association with food selection, meal patterns and related psychobehavioral factors in 10–17 year old adolescents. Altogether 976 10–17 years old Finnish adolescents filled in the study questionnaire. When exploring the construct validity of ecSI 2.0, the confirmatory factor analysis (CFA indicated acceptable model fit and all four components of the ecSI 2.0 (eating attitudes, food acceptance, internal regulation of food intake, management of eating context correlated with each other and were internally consistent. Over half (58% of the adolescents scored 32 or higher and were thus classified as presumably eating competent (pEC. Eating competence was associated with greater meal frequency, more frequent consumption of vegetables and fruits, and more health-promoting family eating patterns. In addition the pEC, adolescents more often perceived their body size as appropriate, had less often tried to lose weight and had a higher self-esteem and a stronger sense of coherence than the not pEC ones. Family eating patterns and self-esteem were the main underlying factors of eating competence. In conclusion, this preliminary study suggests eating competence could be a useful concept to characterize eating patterns and related behaviors and attitudes in adolescents. However, these preliminary findings need to be confirmed in further studies with an instrument fully validated for this age group.

  19. Preliminary Finnish measures of eating competence suggest association with health-promoting eating patterns and related psychobehavioral factors in 10-17 year old adolescents.

    Science.gov (United States)

    Tanja, Tilles-Tirkkonen; Outi, Nuutinen; Sakari, Suominen; Jarmo, Liukkonen; Kaisa, Poutanen; Leila, Karhunen

    2015-05-21

    Eating competence is an attitudinal and behavioral concept, based on The Satter Eating Competence Model. In adults, it has been shown to be associated with a higher quality of diet. Eating competence or its association with the quality of diet has not been studied in adolescents. The aim of the current study was to explore the utility of using a preliminary Finnish translation of the ecSI 2.0 for evaluating presumed eating competence and its association with food selection, meal patterns and related psychobehavioral factors in 10-17 year old adolescents. Altogether 976 10-17 years old Finnish adolescents filled in the study questionnaire. When exploring the construct validity of ecSI 2.0, the confirmatory factor analysis (CFA) indicated acceptable model fit and all four components of the ecSI 2.0 (eating attitudes, food acceptance, internal regulation of food intake, management of eating context) correlated with each other and were internally consistent. Over half (58%) of the adolescents scored 32 or higher and were thus classified as presumably eating competent (pEC). Eating competence was associated with greater meal frequency, more frequent consumption of vegetables and fruits, and more health-promoting family eating patterns. In addition the pEC, adolescents more often perceived their body size as appropriate, had less often tried to lose weight and had a higher self-esteem and a stronger sense of coherence than the not pEC ones. Family eating patterns and self-esteem were the main underlying factors of eating competence. In conclusion, this preliminary study suggests eating competence could be a useful concept to characterize eating patterns and related behaviors and attitudes in adolescents. However, these preliminary findings need to be confirmed in further studies with an instrument fully validated for this age group.

  20. Preliminary Finnish Measures of Eating Competence Suggest Association with Health-Promoting Eating Patterns and Related Psychobehavioral Factors in 10–17 Year Old Adolescents

    Science.gov (United States)

    Tanja, Tilles-Tirkkonen; Outi, Nuutinen; Sakari, Suominen; Jarmo, Liukkonen; Kaisa, Poutanen; Leila, Karhunen

    2015-01-01

    Eating competence is an attitudinal and behavioral concept, based on The Satter Eating Competence Model. In adults, it has been shown to be associated with a higher quality of diet. Eating competence or its association with the quality of diet has not been studied in adolescents. The aim of the current study was to explore the utility of using a preliminary Finnish translation of the ecSI 2.0 for evaluating presumed eating competence and its association with food selection, meal patterns and related psychobehavioral factors in 10–17 year old adolescents. Altogether 976 10–17 years old Finnish adolescents filled in the study questionnaire. When exploring the construct validity of ecSI 2.0, the confirmatory factor analysis (CFA) indicated acceptable model fit and all four components of the ecSI 2.0 (eating attitudes, food acceptance, internal regulation of food intake, management of eating context) correlated with each other and were internally consistent. Over half (58%) of the adolescents scored 32 or higher and were thus classified as presumably eating competent (pEC). Eating competence was associated with greater meal frequency, more frequent consumption of vegetables and fruits, and more health-promoting family eating patterns. In addition the pEC, adolescents more often perceived their body size as appropriate, had less often tried to lose weight and had a higher self-esteem and a stronger sense of coherence than the not pEC ones. Family eating patterns and self-esteem were the main underlying factors of eating competence. In conclusion, this preliminary study suggests eating competence could be a useful concept to characterize eating patterns and related behaviors and attitudes in adolescents. However, these preliminary findings need to be confirmed in further studies with an instrument fully validated for this age group. PMID:26007335

  1. Robust and Sparse Factor Modelling

    DEFF Research Database (Denmark)

    Croux, Christophe; Exterkate, Peter

    Factor construction methods are widely used to summarize a large panel of variables by means of a relatively small number of representative factors. We propose a novel factor construction procedure that enjoys the properties of robustness to outliers and of sparsity; that is, having relatively few...... nonzero factor loadings. Compared to the traditional factor construction method, we find that this procedure leads to a favorable forecasting performance in the presence of outliers and to better interpretable factors. We investigate the performance of the method in a Monte Carlo experiment...

  2. Sparse and Robust Factor Modelling

    NARCIS (Netherlands)

    C. Croux (Christophe); P. Exterkate (Peter)

    2011-01-01

    textabstractFactor construction methods are widely used to summarize a large panel of variables by means of a relatively small number of representative factors. We propose a novel factor construction procedure that enjoys the properties of robustness to outliers and of sparsity; that is, having

  3. Intraspecific niche models for ponderosa pine (Pinus ponderosa) suggest potential variability in population-level response to climate change

    Science.gov (United States)

    Maguire, Kaitlin C.; Shinneman, Douglas; Potter, Kevin M.; Hipkins, Valerie D.

    2018-01-01

    Unique responses to climate change can occur across intraspecific levels, resulting in individualistic adaptation or movement patterns among populations within a given species. Thus, the need to model potential responses among genetically distinct populations within a species is increasingly recognized. However, predictive models of future distributions are regularly fit at the species level, often because intraspecific variation is unknown or is identified only within limited sample locations. In this study, we considered the role of intraspecific variation to shape the geographic distribution of ponderosa pine (Pinus ponderosa), an ecologically and economically important tree species in North America. Morphological and genetic variation across the distribution of ponderosa pine suggest the need to model intraspecific populations: the two varieties (var. ponderosa and var. scopulorum) and several haplotype groups within each variety have been shown to occupy unique climatic niches, suggesting populations have distinct evolutionary lineages adapted to different environmental conditions. We utilized a recently-available, geographically-widespread dataset of intraspecific variation (haplotypes) for ponderosa pine and a recently-devised lineage distance modeling approach to derive additional, likely intraspecific occurrence locations. We confirmed the relative uniqueness of each haplotype-climate relationship using a niche-overlap analysis, and developed ecological niche models (ENMs) to project the distribution for two varieties and eight haplotypes under future climate forecasts. Future projections of haplotype niche distributions generally revealed greater potential range loss than predicted for the varieties. This difference may reflect intraspecific responses of distinct evolutionary lineages. However, directional trends are generally consistent across intraspecific levels, and include a loss of distributional area and an upward shift in elevation. Our results

  4. Intraspecific niche models for ponderosa pine (Pinus ponderosa) suggest potential variability in population-level response to climate change.

    Science.gov (United States)

    Maguire, Kaitlin C; Shinneman, Douglas J; Potter, Kevin M; Hipkins, Valerie D

    2018-03-14

    Unique responses to climate change can occur across intraspecific levels, resulting in individualistic adaptation or movement patterns among populations within a given species. Thus, the need to model potential responses among genetically distinct populations within a species is increasingly recognized. However, predictive models of future distributions are regularly fit at the species level, often because intraspecific variation is unknown or is identified only within limited sample locations. In this study, we considered the role of intraspecific variation to shape the geographic distribution of ponderosa pine (Pinus ponderosa), an ecologically and economically important tree species in North America. Morphological and genetic variation across the distribution of ponderosa pine suggest the need to model intraspecific populations: the two varieties (var. ponderosa and var. scopulorum) and several haplotype groups within each variety have been shown to occupy unique climatic niches, suggesting populations have distinct evolutionary lineages adapted to different environmental conditions. We utilized a recently-available, geographically-widespread dataset of intraspecific variation (haplotypes) for ponderosa pine and a recently-devised lineage distance modeling approach to derive additional, likely intraspecific occurrence locations. We confirmed the relative uniqueness of each haplotype-climate relationship using a niche-overlap analysis, and developed ecological niche models (ENMs) to project the distribution for two varieties and eight haplotypes under future climate forecasts. Future projections of haplotype niche distributions generally revealed greater potential range loss than predicted for the varieties. This difference may reflect intraspecific responses of distinct evolutionary lineages. However, directional trends are generally consistent across intraspecific levels, and include a loss of distributional area and an upward shift in elevation. Our results

  5. Skewed factor models using selection mechanisms

    KAUST Repository

    Kim, Hyoung-Moon

    2015-12-21

    Traditional factor models explicitly or implicitly assume that the factors follow a multivariate normal distribution; that is, only moments up to order two are involved. However, it may happen in real data problems that the first two moments cannot explain the factors. Based on this motivation, here we devise three new skewed factor models, the skew-normal, the skew-tt, and the generalized skew-normal factor models depending on a selection mechanism on the factors. The ECME algorithms are adopted to estimate related parameters for statistical inference. Monte Carlo simulations validate our new models and we demonstrate the need for skewed factor models using the classic open/closed book exam scores dataset.

  6. Skewed factor models using selection mechanisms

    KAUST Repository

    Kim, Hyoung-Moon; Maadooliat, Mehdi; Arellano-Valle, Reinaldo B.; Genton, Marc G.

    2015-01-01

    Traditional factor models explicitly or implicitly assume that the factors follow a multivariate normal distribution; that is, only moments up to order two are involved. However, it may happen in real data problems that the first two moments cannot explain the factors. Based on this motivation, here we devise three new skewed factor models, the skew-normal, the skew-tt, and the generalized skew-normal factor models depending on a selection mechanism on the factors. The ECME algorithms are adopted to estimate related parameters for statistical inference. Monte Carlo simulations validate our new models and we demonstrate the need for skewed factor models using the classic open/closed book exam scores dataset.

  7. Modeling Ability Differentiation in the Second-Order Factor Model

    Science.gov (United States)

    Molenaar, Dylan; Dolan, Conor V.; van der Maas, Han L. J.

    2011-01-01

    In this article we present factor models to test for ability differentiation. Ability differentiation predicts that the size of IQ subtest correlations decreases as a function of the general intelligence factor. In the Schmid-Leiman decomposition of the second-order factor model, we model differentiation by introducing heteroscedastic residuals,…

  8. An integrated disease/pharmacokinetic/pharmacodynamic model suggests improved interleukin-21 regimens validated prospectively for mouse solid cancers.

    Directory of Open Access Journals (Sweden)

    Moran Elishmereni

    2011-09-01

    Full Text Available Interleukin (IL-21 is an attractive antitumor agent with potent immunomodulatory functions. Yet thus far, the cytokine has yielded only partial responses in solid cancer patients, and conditions for beneficial IL-21 immunotherapy remain elusive. The current work aims to identify clinically-relevant IL-21 regimens with enhanced efficacy, based on mathematical modeling of long-term antitumor responses. For this purpose, pharmacokinetic (PK and pharmacodynamic (PD data were acquired from a preclinical study applying systemic IL-21 therapy in murine solid cancers. We developed an integrated disease/PK/PD model for the IL-21 anticancer response, and calibrated it using selected "training" data. The accuracy of the model was verified retrospectively under diverse IL-21 treatment settings, by comparing its predictions to independent "validation" data in melanoma and renal cell carcinoma-challenged mice (R(2>0.90. Simulations of the verified model surfaced important therapeutic insights: (1 Fractionating the standard daily regimen (50 µg/dose into a twice daily schedule (25 µg/dose is advantageous, yielding a significantly lower tumor mass (45% decrease; (2 A low-dose (12 µg/day regimen exerts a response similar to that obtained under the 50 µg/day treatment, suggestive of an equally efficacious dose with potentially reduced toxicity. Subsequent experiments in melanoma-bearing mice corroborated both of these predictions with high precision (R(2>0.89, thus validating the model also prospectively in vivo. Thus, the confirmed PK/PD model rationalizes IL-21 therapy, and pinpoints improved clinically-feasible treatment schedules. Our analysis demonstrates the value of employing mathematical modeling and in silico-guided design of solid tumor immunotherapy in the clinic.

  9. Model suggests potential for Porites coral population recovery after removal of anthropogenic disturbance (Luhuitou, Hainan, South China Sea).

    Science.gov (United States)

    Zhao, Meixia; Riegl, Bernhard; Yu, Kefu; Shi, Qi; Zhang, Qiaomin; Liu, Guohui; Yang, Hongqiang; Yan, Hongqiang

    2016-09-13

    Population models are important for resource management and can inform about potential trajectories useful for planning purposes, even with incomplete monitoring data. From size frequency data on Luhuitou fringing reef, Hainan, South China Sea, a matrix population model of massive corals (Porites lutea) was developed and trajectories over 100 years under no disturbance and random disturbances were projected. The model reflects a largely open population of Porites lutea, with low local recruitment and preponderance of imported recruitment. Under no further disturbance, the population of Porites lutea will grow and its size structure will change from predominance of small size classes to large size classes. Therewith, total Porites cover will increase. Even under random disturbances every 10 to 20 years, the Porites population could remain viable, albeit at lower space cover. The models suggest recovery at Luhuitou following the removal of chronic anthropogenic disturbance. Extending the area of coral reef reserves to protect the open coral community and the path of connectivity is advisable and imperative for the conservation of Hainan's coral reefs.

  10. Model suggests potential for Porites coral population recovery after removal of anthropogenic disturbance (Luhuitou, Hainan, South China Sea)

    Science.gov (United States)

    Zhao, Meixia; Riegl, Bernhard; Yu, Kefu; Shi, Qi; Zhang, Qiaomin; Liu, Guohui; Yang, Hongqiang; Yan, Hongqiang

    2016-09-01

    Population models are important for resource management and can inform about potential trajectories useful for planning purposes, even with incomplete monitoring data. From size frequency data on Luhuitou fringing reef, Hainan, South China Sea, a matrix population model of massive corals (Porites lutea) was developed and trajectories over 100 years under no disturbance and random disturbances were projected. The model reflects a largely open population of Porites lutea, with low local recruitment and preponderance of imported recruitment. Under no further disturbance, the population of Porites lutea will grow and its size structure will change from predominance of small size classes to large size classes. Therewith, total Porites cover will increase. Even under random disturbances every 10 to 20 years, the Porites population could remain viable, albeit at lower space cover. The models suggest recovery at Luhuitou following the removal of chronic anthropogenic disturbance. Extending the area of coral reef reserves to protect the open coral community and the path of connectivity is advisable and imperative for the conservation of Hainan’s coral reefs.

  11. High-resolution mutational profiling suggests the genetic validity of glioblastoma patient-derived pre-clinical models.

    Directory of Open Access Journals (Sweden)

    Shawn E Yost

    Full Text Available Recent advances in the ability to efficiently characterize tumor genomes is enabling targeted drug development, which requires rigorous biomarker-based patient selection to increase effectiveness. Consequently, representative DNA biomarkers become equally important in pre-clinical studies. However, it is still unclear how well these markers are maintained between the primary tumor and the patient-derived tumor models. Here, we report the comprehensive identification of somatic coding mutations and copy number aberrations in four glioblastoma (GBM primary tumors and their matched pre-clinical models: serum-free neurospheres, adherent cell cultures, and mouse xenografts. We developed innovative methods to improve the data quality and allow a strict comparison of matched tumor samples. Our analysis identifies known GBM mutations altering PTEN and TP53 genes, and new actionable mutations such as the loss of PIK3R1, and reveals clear patient-to-patient differences. In contrast, for each patient, we do not observe any significant remodeling of the mutational profile between primary to model tumors and the few discrepancies can be attributed to stochastic errors or differences in sample purity. Similarly, we observe ∼96% primary-to-model concordance in copy number calls in the high-cellularity samples. In contrast to previous reports based on gene expression profiles, we do not observe significant differences at the DNA level between in vitro compared to in vivo models. This study suggests, at a remarkable resolution, the genome-wide conservation of a patient's tumor genetics in various pre-clinical models, and therefore supports their use for the development and testing of personalized targeted therapies.

  12. Organizational suggestion system in the era of holding by developing an innovative model : the case of bonyade ta avon holding in Iran(an applied model

    Directory of Open Access Journals (Sweden)

    Meysam Ghasemi

    2010-01-01

    Full Text Available One of the popular ways of taking advantage of personnel creativity is through suggestionsystems. Our main question is how to implement suggestion system in holding with conglomeratestructure. The paper presents an innovative model that were named ITFSK Model with accordanceof Bonayade Taavone (a holding that has many companies and institutions with conglomeratestructure. ITFSK is a model that explains how participation management and suggestion system isimplemented effectively in huge Enterprises (holding and this approach brings continuousimprovement (kaizen and it impacts the productivity of these enterprises.The paper is based on field research and the research in Bonyade Tavan that has 22 companies and2 institutions that activity fields of the subholdings is very varied.Our model consists of five main parts such as ideas bank, think-tank, feedback, sharing ofknowledge and kaizen that was named ITFSK.Implementation of “Suggestion system” rules has immediate and significant effects on theproductivity of activities in the jobs, thus influencing the performance of processes in the analyzedorganization. Suggestion system can result in kaizen and innovation in environment oforganization.The model was used to implement and evaluate a suggestion system of holding with conglomeratedstructure. The application of the model to evaluate the suggestion system provided some goodinsights and highlighted some areas of improvement.

  13. Modeling of Glycerol-3-Phosphate Transporter Suggests a Potential ‘Tilt’ Mechanism involved in its Function

    Science.gov (United States)

    Tsigelny, Igor F.; Greenberg, Jerry; Kouznetsova, Valentina; Nigam, Sanjay K.

    2009-01-01

    Many major facilitator superfamily (MFS) transporters have similar 12-transmembrane α-helical topologies with two six-helix halves connected by a long loop. In humans, these transporters participate in key physiological processes and are also, as in the case of members of the organic anion transporter (OAT) family, of pharmaceutical interest. Recently, crystal structures of two bacterial representatives of the MFS family — the glycerol-3-phosphate transporter (GlpT) and lac-permease (LacY) — have been solved and, because of assumptions regarding the high structural conservation of this family, there is hope that the results can be applied to mammalian transporters as well. Based on crystallography, it has been suggested that a major conformational “switching” mechanism accounts for ligand transport by MFS proteins. This conformational switch would then allow periodic changes in the overall transporter configuration, resulting in its cyclic opening to the periplasm or cytoplasm. Following this lead, we have modeled a possible “switch” mechanism in GlpT, using the concept of rotation of protein domains as in the DynDom program17 and membranephilic constraints predicted by the MAPAS program.23 We found that the minima of energies of intersubunit interactions support two alternate positions consistent with their transport properties. Thus, for GlpT, a “tilt” of 9°–10° rotation had the most favorable energetics of electrostatic interaction between the two halves of the transporter; moreover, this confirmation was sufficient to suggest transport of the ligand across the membrane. We conducted steered molecular dynamics simulations of the GlpT-ligand system to explore how glycerol-3-phosphate would be handled by the “tilted” structure, and obtained results generally consistent with experimental mutagenesis data. While biochemical data remain most consistent with a single-site alternating access model, our results raise the possibility that, while

  14. Increasing organic C and N fluxes from a northern Boreal river basin - monitoring and modelling suggest climate related controls

    Science.gov (United States)

    Lepistö, A.; Futter, M.; Kortelainen, P.

    2012-04-01

    Increasing trends in total organic carbon (TOC) concentrations in lakes and streams across northern Europe and North America have been reported. Various hypotheses including enhanced decomposition of organic soils, changes in hydrology and flow paths, decreased acid deposition and land use changes have been put forward to explain the widespread occurrence of this phenomenon. Both observational and modelling studies are needed to identify the most important drivers and relevant processes controlling observed trends in TOC concentrations. Typically, TOC concentrations in Finnish rivers and lakes are high. The Simojoki river basin (3160 km2) is located in the northern Boreal zone of Finland and experiences low, declining sulphate deposition and limited other human impacts. Forest harvest, land drainage and ditch maintenance are the main land management activities in the catchment. Long-term changes (30-40 years) and seasonal trends of total organic nitrogen (TON) and carbon (TOC) concentrations and fluxes in the Simojoki river system were studied. Concentrations of TOC and TON increased particularly during high flows. TOC concentrations are slowly but continuously increasing, fluctuating between droughts and wet periods. The highest concentrations were detected in 1998-2000 during a period of very high flows, after the drought period 1994-1997. Trends in concentrations of TOC and TON in Simojoki were not linked to declines in sulphate deposition but were more related to trends in climate and hydrology. The autumn season is particularly sensitive to climate change impacts. The INCA-C model was applied to simulate TOC dynamics in the catchment. Model results showed that climate change driven patterns in runoff and soil moisture and soil temperature were more important than temporal patterns of sulphate deposition and land management in controlling surface water TOC concentrations. The possible factors behind changes of TOC and TON concentrations and increasing fluxes to

  15. Comparison of Transcription Factor Binding Site Models

    KAUST Repository

    Bhuyan, Sharifulislam

    2012-05-01

    Modeling of transcription factor binding sites (TFBSs) and TFBS prediction on genomic sequences are important steps to elucidate transcription regulatory mechanism. Dependency of transcription regulation on a great number of factors such as chemical specificity, molecular structure, genomic and epigenetic characteristics, long distance interaction, makes this a challenging problem. Different experimental procedures generate evidence that DNA-binding domains of transcription factors show considerable DNA sequence specificity. Probabilistic modeling of TFBSs has been moderately successful in identifying patterns from a family of sequences. In this study, we compare performances of different probabilistic models and try to estimate their efficacy over experimental TFBSs data. We build a pipeline to calculate sensitivity and specificity from aligned TFBS sequences for several probabilistic models, such as Markov chains, hidden Markov models, Bayesian networks. Our work, containing relevant statistics and evaluation for the models, can help researchers to choose the most appropriate model for the problem at hand.

  16. Lattice-based model of ductal carcinoma in situ suggests rules for breast cancer progression to an invasive state.

    Directory of Open Access Journals (Sweden)

    Eline Boghaert

    2014-12-01

    Full Text Available Ductal carcinoma in situ (DCIS is a heterogeneous group of non-invasive lesions of the breast that result from abnormal proliferation of mammary epithelial cells. Pathologists characterize DCIS by four tissue morphologies (micropapillary, cribriform, solid, and comedo, but the underlying mechanisms that distinguish the development and progression of these morphologies are not well understood. Here we explored the conditions leading to the emergence of the different morphologies of DCIS using a two-dimensional multi-cell lattice-based model that incorporates cell proliferation, apoptosis, necrosis, adhesion, and contractility. We found that the relative rates of cell proliferation and apoptosis governed which of the four morphologies emerged. High proliferation and low apoptosis favored the emergence of solid and comedo morphologies. In contrast, low proliferation and high apoptosis led to the micropapillary morphology, whereas high proliferation and high apoptosis led to the cribriform morphology. The natural progression between morphologies cannot be investigated in vivo since lesions are usually surgically removed upon detection; however, our model suggests probable transitions between these morphologies during breast cancer progression. Importantly, cribriform and comedo appear to be the ultimate morphologies of DCIS. Motivated by previous experimental studies demonstrating that tumor cells behave differently depending on where they are located within the mammary duct in vivo or in engineered tissues, we examined the effects of tissue geometry on the progression of DCIS. In agreement with our previous experimental work, we found that cells are more likely to invade from the end of ducts and that this preferential invasion is regulated by cell adhesion and contractility. This model provides additional insight into tumor cell behavior and allows the exploration of phenotypic transitions not easily monitored in vivo.

  17. Lattice-based model of ductal carcinoma in situ suggests rules for breast cancer progression to an invasive state.

    Science.gov (United States)

    Boghaert, Eline; Radisky, Derek C; Nelson, Celeste M

    2014-12-01

    Ductal carcinoma in situ (DCIS) is a heterogeneous group of non-invasive lesions of the breast that result from abnormal proliferation of mammary epithelial cells. Pathologists characterize DCIS by four tissue morphologies (micropapillary, cribriform, solid, and comedo), but the underlying mechanisms that distinguish the development and progression of these morphologies are not well understood. Here we explored the conditions leading to the emergence of the different morphologies of DCIS using a two-dimensional multi-cell lattice-based model that incorporates cell proliferation, apoptosis, necrosis, adhesion, and contractility. We found that the relative rates of cell proliferation and apoptosis governed which of the four morphologies emerged. High proliferation and low apoptosis favored the emergence of solid and comedo morphologies. In contrast, low proliferation and high apoptosis led to the micropapillary morphology, whereas high proliferation and high apoptosis led to the cribriform morphology. The natural progression between morphologies cannot be investigated in vivo since lesions are usually surgically removed upon detection; however, our model suggests probable transitions between these morphologies during breast cancer progression. Importantly, cribriform and comedo appear to be the ultimate morphologies of DCIS. Motivated by previous experimental studies demonstrating that tumor cells behave differently depending on where they are located within the mammary duct in vivo or in engineered tissues, we examined the effects of tissue geometry on the progression of DCIS. In agreement with our previous experimental work, we found that cells are more likely to invade from the end of ducts and that this preferential invasion is regulated by cell adhesion and contractility. This model provides additional insight into tumor cell behavior and allows the exploration of phenotypic transitions not easily monitored in vivo.

  18. The Five-Factor Model: General Overview

    Directory of Open Access Journals (Sweden)

    A A Vorobyeva

    2011-12-01

    Full Text Available The article describes the five-factor model (FFM, giving an overview of its history, basic dimensions, cross-cultural research conducted on the model and highlights some practical studies based on the FFM, including the studies on job performance, leader performance and daily social interactions. An overview of the recent five-factor theory is also provided. According to the theory, the five factors are encoded in human genes, therefore it is almost impossible to change the basic factors themselves, but a person's behavior might be changed due to characteristic adaptations which do not alter personality dimensions, only a person's behavior.

  19. Rapid genome reshaping by multiple-gene loss after whole-genome duplication in teleost fish suggested by mathematical modeling

    Science.gov (United States)

    Sato, Yukuto; Tsukamoto, Katsumi; Nishida, Mutsumi

    2015-01-01

    Whole-genome duplication (WGD) is believed to be a significant source of major evolutionary innovation. Redundant genes resulting from WGD are thought to be lost or acquire new functions. However, the rates of gene loss and thus temporal process of genome reshaping after WGD remain unclear. The WGD shared by all teleost fish, one-half of all jawed vertebrates, was more recent than the two ancient WGDs that occurred before the origin of jawed vertebrates, and thus lends itself to analysis of gene loss and genome reshaping. Using a newly developed orthology identification pipeline, we inferred the post–teleost-specific WGD evolutionary histories of 6,892 protein-coding genes from nine phylogenetically representative teleost genomes on a time-calibrated tree. We found that rapid gene loss did occur in the first 60 My, with a loss of more than 70–80% of duplicated genes, and produced similar genomic gene arrangements within teleosts in that relatively short time. Mathematical modeling suggests that rapid gene loss occurred mainly by events involving simultaneous loss of multiple genes. We found that the subsequent 250 My were characterized by slow and steady loss of individual genes. Our pipeline also identified about 1,100 shared single-copy genes that are inferred to have become singletons before the divergence of clupeocephalan teleosts. Therefore, our comparative genome analysis suggests that rapid gene loss just after the WGD reshaped teleost genomes before the major divergence, and provides a useful set of marker genes for future phylogenetic analysis. PMID:26578810

  20. Linear factor copula models and their properties

    KAUST Repository

    Krupskii, Pavel; Genton, Marc G.

    2018-01-01

    We consider a special case of factor copula models with additive common factors and independent components. These models are flexible and parsimonious with O(d) parameters where d is the dimension. The linear structure allows one to obtain closed form expressions for some copulas and their extreme‐value limits. These copulas can be used to model data with strong tail dependencies, such as extreme data. We study the dependence properties of these linear factor copula models and derive the corresponding limiting extreme‐value copulas with a factor structure. We show how parameter estimates can be obtained for these copulas and apply one of these copulas to analyse a financial data set.

  1. Linear factor copula models and their properties

    KAUST Repository

    Krupskii, Pavel

    2018-04-25

    We consider a special case of factor copula models with additive common factors and independent components. These models are flexible and parsimonious with O(d) parameters where d is the dimension. The linear structure allows one to obtain closed form expressions for some copulas and their extreme‐value limits. These copulas can be used to model data with strong tail dependencies, such as extreme data. We study the dependence properties of these linear factor copula models and derive the corresponding limiting extreme‐value copulas with a factor structure. We show how parameter estimates can be obtained for these copulas and apply one of these copulas to analyse a financial data set.

  2. Genomic, RNAseq, and Molecular Modeling Evidence Suggests That the Major Allergen Domain in Insects Evolved from a Homodimeric Origin

    Science.gov (United States)

    Randall, Thomas A.; Perera, Lalith; London, Robert E.; Mueller, Geoffrey A.

    2013-01-01

    The major allergen domain (MA) is widely distributed in insects. The crystal structure of a single Bla g 1 MA revealed a novel protein fold in which the fundamental structure was a duplex of two subsequences (monomers), which had diverged over time. This suggested that the evolutionary origin of the MA structure may have been a homodimer of this smaller subsequence. Using publicly available genomic data, the distribution of the basic unit of this class of proteins was determined to better understand its evolutionary history. The duplication and divergence is examined at three distinct levels of resolution: 1) within the orders Diptera and Hymenoptera, 2) within one genus Drosophila, and 3) within one species Aedes aegypti. Within the family Culicidae, we have found two separate occurrences of monomers as independent genes. The organization of the gene family in A. aegypti shows a common evolutionary origin for its monomer and several closely related MAs. Molecular modeling of the A. aegypti monomer with the unique Bla g 1 fold confirms the distant evolutionary relationship and supports the feasibility of homodimer formation from a single monomer. RNAseq data for A. aegypti confirms that the monomer is expressed in the mosquito similar to other A. aegypti MAs after a blood meal. Together, these data support the contention that the detected monomer shares similar functional characteristics to related MAs in other insects. An extensive search for this domain outside of Insecta confirms that the MAs are restricted to insects. PMID:24253356

  3. Skin care products can aggravate epidermal function: studies in a murine model suggest a pathogenic role in sensitive skin.

    Science.gov (United States)

    Li, Zhengxiao; Hu, Lizhi; Elias, Peter M; Man, Mao-Qiang

    2018-02-01

    Sensitive skin is defined as a spectrum of unpleasant sensations in response to a variety of stimuli. However, only some skin care products provoke cutaneous symptoms in individuals with sensitive skin. Hence, it would be useful to identify products that could provoke cutaneous symptoms in individuals with sensitive skin. To assess whether vehicles, as well as certain branded skin care products, can alter epidermal function following topical applications to normal mouse skin. Following topical applications of individual vehicle or skin care product to C57BL/6J mice twice daily for 4 days, transepidermal water loss (TEWL) rates, stratum corneum (SC) hydration and skin surface pH were measured on treated versus untreated mouse skin with an MPA5 device and pH 900 pH meter. Our results show that all tested products induced abnormalities in epidermal functions of varying severity, including elevations in TEWL and skin surface pH, and reduced SC hydration. Our results suggest that mice can serve as a predictive model that could be used to evaluate the potential safety of skin care products in humans with sensitive skin. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Nonhomologous recombination between defective poliovirus and coxsackievirus genomes suggests a new model of genetic plasticity for picornaviruses.

    Science.gov (United States)

    Holmblat, Barbara; Jégouic, Sophie; Muslin, Claire; Blondel, Bruno; Joffret, Marie-Line; Delpeyroux, Francis

    2014-08-05

    Most of the circulating vaccine-derived polioviruses (cVDPVs) implicated in poliomyelitis outbreaks in Madagascar have been shown to be recombinants between the type 2 poliovirus (PV) strain of the oral polio vaccine (Sabin 2) and another species C human enterovirus (HEV-C), such as type 17 coxsackie A virus (CA17) in particular. We studied intertypic genetic exchanges between PV and non-PV HEV-C by developing a recombination model, making it possible to rescue defective type 2 PV RNA genomes with a short deletion at the 3' end by the cotransfection of cells with defective or infectious CA17 RNAs. We isolated over 200 different PV/CA17 recombinants, using murine cells expressing the human PV receptor (PVR) and selecting viruses with PV capsids. We found some homologous (H) recombinants and, mostly, nonhomologous (NH) recombinants presenting duplications of parental sequences preferentially located in the regions encoding proteins 2A, 2B, and 3A. Short duplications appeared to be stable, whereas longer duplications were excised during passaging in cultured cells or after multiplication in PVR-transgenic mice, generating H recombinants with diverse sites of recombination. This suggests that NH recombination events may be a transient, intermediate step in the generation and selection of the fittest H recombinants. In addition to the classical copy-choice mechanism of recombination thought to generate mostly H recombinants, there may also be a modular mechanism of recombination, involving NH recombinant precursors, shaping the genomes of recombinant enteroviruses and other picornaviruses. Importance: The multiplication of circulating vaccine-derived polioviruses (cVDPVs) in poorly immunized human populations can render these viruses pathogenic, causing poliomyelitis outbreaks. Most cVDPVs are intertypic recombinants between a poliovirus (PV) strain and another human enterovirus, such as type 17 coxsackie A viruses (CA17). For further studies of the genetic exchanges

  5. Some major problems with existing models and terminology associated with kimberlite pipes from a volcanological perspective, and some suggestions

    Science.gov (United States)

    Cas, R. A. F.; Hayman, P.; Pittari, A.; Porritt, L.

    2008-06-01

    have a more factual, descriptive basis, but are still inadequately documented given the recency of their discovery. The diversity amongst kimberlite bodies suggests that a three-model classification is an over-simplification. Every kimberlite is altered to varying degrees, which is an intrinsic consequence of the ultrabasic composition of kimberlite and the in-vent context; few preserve original textures. The effects of syn- to post-emplacement alteration on original textures have not been adequately considered to date, and should be back-stripped to identify original textural elements and configurations. Applying sedimentological textural configurations as a guide to emplacement processes would be useful. The traditional terminology has many connotations about spatial position in pipe and of process. Perhaps the traditional terminology can be retained in the industrial situation as a general lithofacies-mining terminological scheme because it is so entrenched. However, for research purposes a more descriptive lithofacies terminology should be adopted to facilitate detailed understanding of deposit characteristics, important variations in these, and the process origins. For example every deposit of TKB is different in componentry, texture, or depositional structure. However, because so many deposits in many different pipes are called TKB, there is an implication that they are all similar and that similar processes were involved, which is far from clear.

  6. Nonhomologous Recombination between Defective Poliovirus and Coxsackievirus Genomes Suggests a New Model of Genetic Plasticity for Picornaviruses

    Science.gov (United States)

    Holmblat, Barbara; Jégouic, Sophie; Muslin, Claire; Blondel, Bruno; Joffret, Marie-Line

    2014-01-01

    ABSTRACT Most of the circulating vaccine-derived polioviruses (cVDPVs) implicated in poliomyelitis outbreaks in Madagascar have been shown to be recombinants between the type 2 poliovirus (PV) strain of the oral polio vaccine (Sabin 2) and another species C human enterovirus (HEV-C), such as type 17 coxsackie A virus (CA17) in particular. We studied intertypic genetic exchanges between PV and non-PV HEV-C by developing a recombination model, making it possible to rescue defective type 2 PV RNA genomes with a short deletion at the 3′ end by the cotransfection of cells with defective or infectious CA17 RNAs. We isolated over 200 different PV/CA17 recombinants, using murine cells expressing the human PV receptor (PVR) and selecting viruses with PV capsids. We found some homologous (H) recombinants and, mostly, nonhomologous (NH) recombinants presenting duplications of parental sequences preferentially located in the regions encoding proteins 2A, 2B, and 3A. Short duplications appeared to be stable, whereas longer duplications were excised during passaging in cultured cells or after multiplication in PVR-transgenic mice, generating H recombinants with diverse sites of recombination. This suggests that NH recombination events may be a transient, intermediate step in the generation and selection of the fittest H recombinants. In addition to the classical copy-choice mechanism of recombination thought to generate mostly H recombinants, there may also be a modular mechanism of recombination, involving NH recombinant precursors, shaping the genomes of recombinant enteroviruses and other picornaviruses. PMID:25096874

  7. A compilation of radionuclide transfer factors for the plant, meat, milk, and aquatic food pathways and the suggested default values for the RESRAD code

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.Y.; Biwer, B.M.; Yu, C.

    1993-08-01

    The ongoing development and revision of the RESRAD computer code at Argonne National Laboratory requires update of radionuclide transfer factors for the plant, meat, milk, and aquatic food pathways. Default values for these transfer factors used in published radiological assessment reports are compiled and compared with values used in RESRAD. The differences among the reported default values used in different radiological assessment codes and reports are also discussed. In data comparisons, values used in more recent reports are given more weight because more recent experimental work tends to be conducted under better-defined laboratory or field conditions. A new default value is suggested for RESRAD if one of the following conditions is met: (1) values used in recent reports are an order of magnitude higher or lower than the default value currently used in RESRAD, or (2) the same default value is used in several recent radiological assessment reports.

  8. A hierarchical model for ordinal matrix factorization

    DEFF Research Database (Denmark)

    Paquet, Ulrich; Thomson, Blaise; Winther, Ole

    2012-01-01

    This paper proposes a hierarchical probabilistic model for ordinal matrix factorization. Unlike previous approaches, we model the ordinal nature of the data and take a principled approach to incorporating priors for the hidden variables. Two algorithms are presented for inference, one based...

  9. Dynamic Factor Models for the Volatility Surface

    DEFF Research Database (Denmark)

    van der Wel, Michel; Ozturk, Sait R.; Dijk, Dick van

    The implied volatility surface is the collection of volatilities implied by option contracts for different strike prices and time-to-maturity. We study factor models to capture the dynamics of this three-dimensional implied volatility surface. Three model types are considered to examine desirable...

  10. The asset pricing model of musharakah factors

    Science.gov (United States)

    Simon, Shahril; Omar, Mohd; Lazam, Norazliani Md

    2015-02-01

    The existing three-factor model developed by Fama and French for conventional investment was formulated based on risk-free rates element in which contradict with Shariah principles. We note that the underlying principles that govern Shariah investment were mutual risk and profit sharing between parties, the assurance of fairness for all and that transactions were based on an underlying asset. In addition, the three-factor model did not exclude stock that was not permissible by Shariah such as financial services based on riba (interest), gambling operator, manufacture or sale of non-halal products or related products and other activities deemed non-permissible according to Shariah. Our approach to construct the factor model for Shariah investment was based on the basic tenets of musharakah in tabulating the factors. We start by noting that Islamic stocks with similar characteristics should have similar returns and risks. This similarity between Islamic stocks was defined by the similarity of musharakah attributes such as business, management, profitability and capital. These attributes define factor exposures (or betas) to factors. The main takeaways were that musharakah attributes we chose had explain stock returns well in cross section and were significant in different market environments. The management factor seemed to be responsible for the general dynamics of the explanatory power.

  11. Serum Levels of Human MIC-1/GDF15 Vary in a Diurnal Pattern, Do Not Display a Profile Suggestive of a Satiety Factor and Are Related to BMI.

    Directory of Open Access Journals (Sweden)

    Vicky Wang-Wei Tsai

    Full Text Available The TGF-b superfamily cytokine MIC-1/GDF15 circulates in the blood of healthy humans. Its levels rise substantially in cancer and other diseases and this may sometimes lead to development of an anorexia/cachexia syndrome. This is mediated by a direct action of MIC-1/GDF15 on feeding centres in the hypothalamus and brainstem. More recent studies in germline gene deleted mice also suggest that this cytokine may play a role in physiological regulation of energy homeostasis. To further characterize the role of MIC-1/GDF15 in physiological regulation of energy homeostasis in man, we have examined diurnal and food associated variation in serum levels and whether variation in circulating levels relate to BMI in human monozygotic twin pairs. We found that the within twin pair differences in serum MIC-1/GDF15 levels were significantly correlated with within twin pair differences in BMI, suggesting a role for MIC-1/GDF15 in the regulation of energy balance in man. MIC-1/GDF15 serum levels altered slightly in response to a meal, but comparison with variation its serum levels over a 24 hour period suggested that these changes are likely to be due to bimodal diurnal variation which can alter serum MIC-1/GDF15 levels by about plus or minus 10% from the mesor. The lack of a rapid and substantial postprandial increase in MIC-1/GDF15 serum levels suggests that MIC1/GDF15 is unlikely to act as a satiety factor. Taken together, our findings suggest that MIC-1/GDF15 may be a physiological regulator of energy homeostasis in man, most probably due to actions on long-term regulation of energy homeostasis.

  12. Factor Copula Models for Replicated Spatial Data

    KAUST Repository

    Krupskii, Pavel

    2016-12-19

    We propose a new copula model that can be used with replicated spatial data. Unlike the multivariate normal copula, the proposed copula is based on the assumption that a common factor exists and affects the joint dependence of all measurements of the process. Moreover, the proposed copula can model tail dependence and tail asymmetry. The model is parameterized in terms of a covariance function that may be chosen from the many models proposed in the literature, such as the Matérn model. For some choice of common factors, the joint copula density is given in closed form and therefore likelihood estimation is very fast. In the general case, one-dimensional numerical integration is needed to calculate the likelihood, but estimation is still reasonably fast even with large data sets. We use simulation studies to show the wide range of dependence structures that can be generated by the proposed model with different choices of common factors. We apply the proposed model to spatial temperature data and compare its performance with some popular geostatistics models.

  13. Factor Copula Models for Replicated Spatial Data

    KAUST Repository

    Krupskii, Pavel; Huser, Raphaë l; Genton, Marc G.

    2016-01-01

    We propose a new copula model that can be used with replicated spatial data. Unlike the multivariate normal copula, the proposed copula is based on the assumption that a common factor exists and affects the joint dependence of all measurements of the process. Moreover, the proposed copula can model tail dependence and tail asymmetry. The model is parameterized in terms of a covariance function that may be chosen from the many models proposed in the literature, such as the Matérn model. For some choice of common factors, the joint copula density is given in closed form and therefore likelihood estimation is very fast. In the general case, one-dimensional numerical integration is needed to calculate the likelihood, but estimation is still reasonably fast even with large data sets. We use simulation studies to show the wide range of dependence structures that can be generated by the proposed model with different choices of common factors. We apply the proposed model to spatial temperature data and compare its performance with some popular geostatistics models.

  14. A Multinomial Probit Model with Latent Factors

    DEFF Research Database (Denmark)

    Piatek, Rémi; Gensowski, Miriam

    2017-01-01

    be meaningfully linked to an economic model. We provide sufficient conditions that make this structure identified and interpretable. For inference, we design a Markov chain Monte Carlo sampler based on marginal data augmentation. A simulation exercise shows the good numerical performance of our sampler......We develop a parametrization of the multinomial probit model that yields greater insight into the underlying decision-making process, by decomposing the error terms of the utilities into latent factors and noise. The latent factors are identified without a measurement system, and they can...

  15. Effect of plants in constructed wetlands for organic carbon and nutrient removal: a review of experimental factors contributing to higher impact and suggestions for future guidelines.

    Science.gov (United States)

    Jesus, João M; Danko, Anthony S; Fiúza, António; Borges, Maria-Teresa

    2018-02-01

    Constructed wetland is a proven technology for water pollution removal, but process mechanisms and their respective contribution are not fully understood. The present review details the effect of plants on removal efficiency of constructed wetlands by focusing on literature that includes experiments with unplanted controls for organic carbon and nutrient (N and P) removal. The contribution of plant direct uptake is also assessed. Although it was found that several studies, mostly at laboratory or pilot scales, showed no statistical differences between planted and unplanted controls, some factors were found that help maximize the effect of plants. This study intends to contribute to a better understanding of the significance of the effect of plants in a constructed wetland, as well as to suggest a set of experimental guidelines in this field.

  16. Analysing population numbers of the house sparrow in the Netherlands with a matrix model and suggestions for conservation measures

    NARCIS (Netherlands)

    Klok, C.; Holtkamp, R.; Apeldoorn, van R.C.; Visser, M.E.; Hemerik, L.

    2006-01-01

    The House Sparrow (Passer domesticus), formerly a common bird species, has shown a rapid decline in Western Europe over recent decades. In The Netherlands, its decline is apparent from 1990 onwards. Many causes for this decline have been suggested that all decrease the vital rates, i.e. survival and

  17. Exposure–response model for sibutramine and placebo: suggestion for application to long-term weight-control drug development

    Science.gov (United States)

    Han, Seunghoon; Jeon, Sangil; Hong, Taegon; Lee, Jongtae; Bae, Soo Hyeon; Park, Wan-su; Park, Gab-jin; Youn, Sunil; Jang, Doo Yeon; Kim, Kyung-Soo; Yim, Dong-Seok

    2015-01-01

    No wholly successful weight-control drugs have been developed to date, despite the tremendous demand. We present an exposure–response model of sibutramine mesylate that can be applied during clinical development of other weight-control drugs. Additionally, we provide a model-based evaluation of sibutramine efficacy. Data from a double-blind, randomized, placebo-controlled, multicenter study were used (N=120). Subjects in the treatment arm were initially given 8.37 mg sibutramine base daily, and those who lost sibutramine, including the placebo effect, were modeled using NONMEM 7.2. An asymptotic model approaching the final body weight was chosen to describe the time course of weight loss. Extent of weight loss was described successfully using a sigmoidal exposure–response relationship of the drug with a constant placebo effect in each individual. The placebo effect was influenced by subjects’ sex and baseline body mass index. Maximal weight loss was predicted to occur around 1 year after treatment initiation. The difference in mean weight loss between the sibutramine (daily 12.55 mg) and placebo groups was predicted to be 4.5% in a simulation of 1 year of treatment, with considerable overlap of prediction intervals. Our exposure–response model, which included the placebo effect, is the first example of a quantitative model that can be used to predict the efficacy of weight-control drugs. Similar approaches can help decision-making during clinical development of novel weight-loss drugs. PMID:26392753

  18. Exposure-response model for sibutramine and placebo: suggestion for application to long-term weight-control drug development.

    Science.gov (United States)

    Han, Seunghoon; Jeon, Sangil; Hong, Taegon; Lee, Jongtae; Bae, Soo Hyeon; Park, Wan-su; Park, Gab-jin; Youn, Sunil; Jang, Doo Yeon; Kim, Kyung-Soo; Yim, Dong-Seok

    2015-01-01

    No wholly successful weight-control drugs have been developed to date, despite the tremendous demand. We present an exposure-response model of sibutramine mesylate that can be applied during clinical development of other weight-control drugs. Additionally, we provide a model-based evaluation of sibutramine efficacy. Data from a double-blind, randomized, placebo-controlled, multicenter study were used (N=120). Subjects in the treatment arm were initially given 8.37 mg sibutramine base daily, and those who lost sibutramine, including the placebo effect, were modeled using NONMEM 7.2. An asymptotic model approaching the final body weight was chosen to describe the time course of weight loss. Extent of weight loss was described successfully using a sigmoidal exposure-response relationship of the drug with a constant placebo effect in each individual. The placebo effect was influenced by subjects' sex and baseline body mass index. Maximal weight loss was predicted to occur around 1 year after treatment initiation. The difference in mean weight loss between the sibutramine (daily 12.55 mg) and placebo groups was predicted to be 4.5% in a simulation of 1 year of treatment, with considerable overlap of prediction intervals. Our exposure-response model, which included the placebo effect, is the first example of a quantitative model that can be used to predict the efficacy of weight-control drugs. Similar approaches can help decision-making during clinical development of novel weight-loss drugs.

  19. Didactical suggestion for a Dynamic Hybrid Intelligent e-Learning Environment (DHILE) applying the PENTHA ID Model

    Science.gov (United States)

    dall'Acqua, Luisa

    2011-08-01

    The teleology of our research is to propose a solution to the request of "innovative, creative teaching", proposing a methodology to educate creative Students in a society characterized by multiple reference points and hyper dynamic knowledge, continuously subject to reviews and discussions. We apply a multi-prospective Instructional Design Model (PENTHA ID Model), defined and developed by our research group, which adopts a hybrid pedagogical approach, consisting of elements of didactical connectivism intertwined with aspects of social constructivism and enactivism. The contribution proposes an e-course structure and approach, applying the theoretical design principles of the above mentioned ID Model, describing methods, techniques, technologies and assessment criteria for the definition of lesson modes in an e-course.

  20. Bifurcation Analysis of an Existing Mathematical Model Reveals Novel Treatment Strategies and Suggests Potential Cure for Type 1 Diabetes

    DEFF Research Database (Denmark)

    Nielsen, Kenneth Hagde Mandrup; Ottesen, Johnny T.; Pociot, Flemming

    2014-01-01

    Type 1 diabetes is a disease with serious personal and socioeconomic consequences that has attracted the attention of modellers recently. But as models of this disease tend to be complicated, there has been only limited mathematical analysis to date. Here we address this problem by providing...... a bifurcation analysis of a previously published mathematical model for the early stages of type 1 diabetes in diabetes-prone NOD mice, which is based on the data available in the literature. We also show positivity and the existence of a family of attracting trapping regions in the positive 5D cone, converging...... or activated macrophages, increasing the phagocytic ability of resting and activated macrophages simultaneously and lastly, adding additional macrophages to the site of inflammation. The latter seems counter-intuitive at first glance, but nevertheless it appears to be the most promising, as evidenced by recent...

  1. Challenges and uncertainties in hydrological modelling of remote Hindu Kush-Himalayan (HKH) basins: suggestions for calibration strategies

    NARCIS (Netherlands)

    Pellicciotti, F.; Konz, M.; Immerzeel, W.W.; Shresta, A.B.

    2012-01-01

    Assessment of water resources from remote mountainous catchments plays a crucial role for the development of rural areas in or in the vicinity of mountain ranges. The scarcity of data, however, prevents the application of standard approaches that are based on data-driven models. The Hindu

  2. Matrix factorizations, minimal models and Massey products

    International Nuclear Information System (INIS)

    Knapp, Johanna; Omer, Harun

    2006-01-01

    We present a method to compute the full non-linear deformations of matrix factorizations for ADE minimal models. This method is based on the calculation of higher products in the cohomology, called Massey products. The algorithm yields a polynomial ring whose vanishing relations encode the obstructions of the deformations of the D-branes characterized by these matrix factorizations. This coincides with the critical locus of the effective superpotential which can be computed by integrating these relations. Our results for the effective superpotential are in agreement with those obtained from solving the A-infinity relations. We point out a relation to the superpotentials of Kazama-Suzuki models. We will illustrate our findings by various examples, putting emphasis on the E 6 minimal model

  3. Testing alternative factor models of PTSD and the robustness of the dysphoria factor.

    Science.gov (United States)

    Elklit, Ask; Armour, Cherie; Shevlin, Mark

    2010-01-01

    This study first aimed to examine the structure of self-reported posttraumatic stress disorder (PTSD) symptoms using three different samples. The second aim of the paper was to test the robustness of the factor analytic model when depression scores were controlled for. Based on previous factor analytic findings and the DSM-IV formulation, six confirmatory factor models were specified and estimated that reflected different symptom clusters. The best fitting model was subsequently re-fitted to the data after including a depression variable. The analyses were based on responses from 973 participants across three samples. Sample 1 consisted of 633 parents who were members of 'The National Association of Infant Death' and who had lost a child. Sample 2 consisted of 227 victims of rape, who completed a questionnaire within 4 weeks of the rape. Each respondent had been in contact with the Centre for Rape Victims (CRV) at the Aarhus University Hospital, Denmark. Sample 3 consisted of 113 refugees resident in Denmark. All participants had been referred to a treatment centre which focused on rehabilitating refugees through treatment for psychosocial integration problems (RRCF: Rehabliterings og Revliderings Centre for Flygtninge). In total 500 participants received a diagnosis of PTSD/sub-clinical PTSD (Sample 1, N=214; 2, N=176; 3, N=110). A correlated four-factor model with re-experiencing, avoidance, dysphoria, and arousal factors provided the best fit to the sample data. The average attenuation in the factor loadings was highest for the dysphoria factor (M=-.26, SD=.11) compared to the re-experiencing (M=-.14, SD=.18), avoidance (M=-.10, SD=.21), and arousal (M=-.09, SD=.13) factors. With regards to the best fitting factor model these results concur with previous research findings using different trauma populations but do not reflect the current DSM-IV symptom groupings. The attenuation of dysphoria factor loadings suggests that dysphoria is a non-specific component of

  4. Analysis of HIV-1 intersubtype recombination breakpoints suggests region with high pairing probability may be a more fundamental factor than sequence similarity affecting HIV-1 recombination.

    Science.gov (United States)

    Jia, Lei; Li, Lin; Gui, Tao; Liu, Siyang; Li, Hanping; Han, Jingwan; Guo, Wei; Liu, Yongjian; Li, Jingyun

    2016-09-21

    With increasing data on HIV-1, a more relevant molecular model describing mechanism details of HIV-1 genetic recombination usually requires upgrades. Currently an incomplete structural understanding of the copy choice mechanism along with several other issues in the field that lack elucidation led us to perform an analysis of the correlation between breakpoint distributions and (1) the probability of base pairing, and (2) intersubtype genetic similarity to further explore structural mechanisms. Near full length sequences of URFs from Asia, Europe, and Africa (one sequence/patient), and representative sequences of worldwide CRFs were retrieved from the Los Alamos HIV database. Their recombination patterns were analyzed by jpHMM in detail. Then the relationships between breakpoint distributions and (1) the probability of base pairing, and (2) intersubtype genetic similarities were investigated. Pearson correlation test showed that all URF groups and the CRF group exhibit the same breakpoint distribution pattern. Additionally, the Wilcoxon two-sample test indicated a significant and inexplicable limitation of recombination in regions with high pairing probability. These regions have been found to be strongly conserved across distinct biological states (i.e., strong intersubtype similarity), and genetic similarity has been determined to be a very important factor promoting recombination. Thus, the results revealed an unexpected disagreement between intersubtype similarity and breakpoint distribution, which were further confirmed by genetic similarity analysis. Our analysis reveals a critical conflict between results from natural HIV-1 isolates and those from HIV-1-based assay vectors in which genetic similarity has been shown to be a very critical factor promoting recombination. These results indicate the region with high-pairing probabilities may be a more fundamental factor affecting HIV-1 recombination than sequence similarity in natural HIV-1 infections. Our

  5. Exposure–response model for sibutramine and placebo: suggestion for application to long-term weight-control drug development

    Directory of Open Access Journals (Sweden)

    Han S

    2015-09-01

    Full Text Available Seunghoon Han,1,2 Sangil Jeon,1,2 Taegon Hong,1,2 Jongtae Lee,1,2 Soo Hyeon Bae,1,2 Wan-su Park,1,2 Gab-jin Park,1,2 Sunil Youn,1,2 Doo Yeon Jang,1,2 Kyung-Soo Kim,3 Dong-Seok Yim1,2 1Department of Pharmacology, College of Medicine, The Catholic University of Korea, 2Pharmacometrics Institute for Practical Education and Training, 3Department of Family Medicine, Seoul St Mary’s Hospital, Seochogu, Seoul, Republic of KoreaAbstract: No wholly successful weight-control drugs have been developed to date, despite the tremendous demand. We present an exposure–response model of sibutramine mesylate that can be applied during clinical development of other weight-control drugs. Additionally, we provide a model-based evaluation of sibutramine efficacy. Data from a double-blind, randomized, placebo-controlled, multicenter study were used (N=120. Subjects in the treatment arm were initially given 8.37 mg sibutramine base daily, and those who lost <2 kg after 4 weeks’ treatment were escalated to 12.55 mg. The duration of treatment was 24 weeks. Drug concentration and body weight were measured predose and at 4 weeks, 8 weeks, and 24 weeks after treatment initiation. Exposure and response to sibutramine, including the placebo effect, were modeled using NONMEM 7.2. An asymptotic model approaching the final body weight was chosen to describe the time course of weight loss. Extent of weight loss was described successfully using a sigmoidal exposure–response relationship of the drug with a constant placebo effect in each individual. The placebo effect was influenced by subjects’ sex and baseline body mass index. Maximal weight loss was predicted to occur around 1 year after treatment initiation. The difference in mean weight loss between the sibutramine (daily 12.55 mg and placebo groups was predicted to be 4.5% in a simulation of 1 year of treatment, with considerable overlap of prediction intervals. Our exposure–response model, which

  6. An interactive activation and competition model of person knowledge, suggested by proactive interference by traits spontaneously inferred from behaviours.

    Science.gov (United States)

    Wang, Yuanbo E; Higgins, Nancy C; Uleman, James S; Michaux, Aaron; Vipond, Douglas

    2016-03-01

    People unconsciously and unintentionally make inferences about others' personality traits based on their behaviours. In this study, a classic memory phenomenon--proactive interference (PI)--is for the first time used to detect spontaneous trait inferences. PI should occur when lists of behaviour descriptions, all implying the same trait, are to be remembered. Switching to a new trait should produce 'release' from proactive interference (or RPI). Results from two experiments supported these predictions. PI and RPI effects are consistent with an interactive activation and competition model of person perception (e.g., McNeill & Burton, 2002, J. Exp. Psychol., 55A, 1141), which predicts categorical organization of social behaviours based on personality traits. Advantages of this model are discussed. © 2015 The British Psychological Society.

  7. A novel adoptive transfer model of chronic lymphocytic leukemia suggests a key role for T lymphocytes in the disease

    OpenAIRE

    Bagnara, Davide; Kaufman, Matthew S.; Calissano, Carlo; Marsilio, Sonia; Patten, Piers E. M.; Simone, Rita; Chum, Philip; Yan, Xiao-Jie; Allen, Steven L.; Kolitz, Jonathan E.; Baskar, Sivasubramanian; Rader, Christoph; Mellstedt, Hakan; Rabbani, Hodjattallah; Lee, Annette

    2011-01-01

    Chronic lymphocytic leukemia (CLL) is an incurable adult disease of unknown etiology. Understanding the biology of CLL cells, particularly cell maturation and growth in vivo, has been impeded by lack of a reproducible adoptive transfer model. We report a simple, reproducible system in which primary CLL cells proliferate in nonobese diabetes/severe combined immunodeficiency/γcnull mice under the influence of activated CLL-derived T lymphocytes. By cotransferring autologous T lymphocytes, activ...

  8. Synthetic biology between challenges and risks: suggestions for a model of governance and a regulatory framework, based on fundamental rights.

    Science.gov (United States)

    Colussi, Ilaria Anna

    2013-01-01

    This paper deals with the emerging synthetic biology, its challenges and risks, and tries to design a model for the governance and regulation of the field. The model is called of "prudent vigilance" (inspired by the report about synthetic biology, drafted by the U.S. Presidential Commission on Bioethics, 2010), and it entails (a) an ongoing and periodically revised process of assessment and management of all the risks and concerns, and (b) the adoption of policies - taken through "hard law" and "soft law" sources - that are based on the principle of proportionality (among benefits and risks), on a reasonable balancing between different interests and rights at stake, and are oriented by a constitutional frame, which is represented by the protection of fundamental human rights emerging in the field of synthetic biology (right to life, right to health, dignity, freedom of scientific research, right to environment). After the theoretical explanation of the model, its operability is "checked", by considering its application with reference to only one specific risk brought up by synthetic biology - biosecurity risk, i.e. the risk of bioterrorism.

  9. VDR regulation of microRNA differs across prostate cell models suggesting extremely flexible control of transcription.

    Science.gov (United States)

    Singh, Prashant K; Long, Mark D; Battaglia, Sebastiano; Hu, Qiang; Liu, Song; Sucheston-Campbell, Lara E; Campbell, Moray J

    2015-01-01

    The Vitamin D Receptor (VDR) is a member of the nuclear receptor superfamily and is of therapeutic interest in cancer and other settings. Regulation of microRNA (miRNA) by the VDR appears to be important to mediate its actions, for example, to control cell growth. To identify if and to what extent VDR-regulated miRNA patterns change in prostate cancer progression, we undertook miRNA microarray analyses in 7 cell models representing non-malignant and malignant prostate cells (RWPE-1, RWPE-2, HPr1, HPr1AR, LNCaP, LNCaP-C4-2, and PC-3). To focus on primary VDR regulatory events, we undertook expression analyses after 30 minutes treatment with 1α,25(OH)2D3. Across all models, 111 miRNAs were significantly modulated by 1α,25(OH)2D3 treatment. Of these, only 5 miRNAs were modulated in more than one cell model, and of these, only 3 miRNAs were modulated in the same direction. The patterns of miRNA regulation, and the networks they targeted, significantly distinguished the different cell types. Integration of 1α,25(OH)2D3-regulated miRNAs with published VDR ChIP-seq data showed significant enrichment of VDR peaks in flanking regions of miRNAs. Furthermore, mRNA and miRNA expression analyses in non-malignant RWPE-1 cells revealed patterns of miRNA and mRNA co-regulation; specifically, 13 significant reciprocal patterns were identified and these patterns were also observed in TCGA prostate cancer data. Lastly, motif search analysis revealed differential motif enrichment within VDR peaks flanking mRNA compared to miRNA genes. Together, this study revealed that miRNAs are rapidly regulated in a highly cell-type specific manner, and are significantly co-integrated with mRNA regulation.

  10. The structure of musical preferences: a five-factor model.

    Science.gov (United States)

    Rentfrow, Peter J; Goldberg, Lewis R; Levitin, Daniel J

    2011-06-01

    Music is a cross-cultural universal, a ubiquitous activity found in every known human culture. Individuals demonstrate manifestly different preferences in music, and yet relatively little is known about the underlying structure of those preferences. Here, we introduce a model of musical preferences based on listeners' affective reactions to excerpts of music from a wide variety of musical genres. The findings from 3 independent studies converged to suggest that there exists a latent 5-factor structure underlying music preferences that is genre free and reflects primarily emotional/affective responses to music. We have interpreted and labeled these factors as (a) a Mellow factor comprising smooth and relaxing styles; (b) an Unpretentious factor comprising a variety of different styles of sincere and rootsy music such as is often found in country and singer-songwriter genres; (c) a Sophisticated factor that includes classical, operatic, world, and jazz; (d) an Intense factor defined by loud, forceful, and energetic music; and (e) a Contemporary factor defined largely by rhythmic and percussive music, such as is found in rap, funk, and acid jazz. The findings from a fourth study suggest that preferences for the MUSIC factors are affected by both the social and the auditory characteristics of the music. 2011 APA, all rights reserved

  11. Simulated Models Suggest That Price per Calorie Is the Dominant Price Metric That Low-Income Individuals Use for Food Decision Making.

    Science.gov (United States)

    Beheshti, Rahmatollah; Igusa, Takeru; Jones-Smith, Jessica

    2016-11-01

    The price of food has long been considered one of the major factors that affects food choices. However, the price metric (e.g., the price of food per calorie or the price of food per gram) that individuals predominantly use when making food choices is unclear. Understanding which price metric is used is especially important for studying individuals with severe budget constraints because food price then becomes even more important in food choice. We assessed which price metric is used by low-income individuals in deciding what to eat. With the use of data from NHANES and the USDA Food and Nutrient Database for Dietary Studies, we created an agent-based model that simulated an environment representing the US population, wherein individuals were modeled as agents with a specific weight, age, and income. In our model, agents made dietary food choices while meeting their budget limits with the use of 1 of 3 different metrics for decision making: energy cost (price per calorie), unit price (price per gram), and serving price (price per serving). The food consumption patterns generated by our model were compared to 3 independent data sets. The food choice behaviors observed in 2 of the data sets were found to be closest to the simulated dietary patterns generated by the price per calorie metric. The behaviors observed in the third data set were equidistant from the patterns generated by price per calorie and price per serving metrics, whereas results generated by the price per gram metric were further away. Our simulations suggest that dietary food choice based on price per calorie best matches actual consumption patterns and may therefore be the most salient price metric for low-income populations. © 2016 American Society for Nutrition.

  12. Simulated Models Suggest That Price per Calorie Is the Dominant Price Metric That Low-Income Individuals Use for Food Decision Making123

    Science.gov (United States)

    2016-01-01

    Background: The price of food has long been considered one of the major factors that affects food choices. However, the price metric (e.g., the price of food per calorie or the price of food per gram) that individuals predominantly use when making food choices is unclear. Understanding which price metric is used is especially important for studying individuals with severe budget constraints because food price then becomes even more important in food choice. Objective: We assessed which price metric is used by low-income individuals in deciding what to eat. Methods: With the use of data from NHANES and the USDA Food and Nutrient Database for Dietary Studies, we created an agent-based model that simulated an environment representing the US population, wherein individuals were modeled as agents with a specific weight, age, and income. In our model, agents made dietary food choices while meeting their budget limits with the use of 1 of 3 different metrics for decision making: energy cost (price per calorie), unit price (price per gram), and serving price (price per serving). The food consumption patterns generated by our model were compared to 3 independent data sets. Results: The food choice behaviors observed in 2 of the data sets were found to be closest to the simulated dietary patterns generated by the price per calorie metric. The behaviors observed in the third data set were equidistant from the patterns generated by price per calorie and price per serving metrics, whereas results generated by the price per gram metric were further away. Conclusions: Our simulations suggest that dietary food choice based on price per calorie best matches actual consumption patterns and may therefore be the most salient price metric for low-income populations. PMID:27655757

  13. In vivo evidence suggesting reciprocal renal hypoxia-inducible factor-1 upregulation and signal transducer and activator of transcription 3 activation in response to hypoxic and non-hypoxic stimuli.

    Science.gov (United States)

    Nechemia-Arbely, Yael; Khamaisi, Mogher; Rosenberger, Christian; Koesters, Robert; Shina, Ahuva; Geva, Carmit; Shriki, Anat; Klaus, Stephen; Rosen, Seymour; Rose-John, Stefan; Galun, Eithan; Axelrod, Jonathan H; Heyman, Samuel N

    2013-04-01

    In vitro studies suggest that combined activation of hypoxia-inducible factor (HIF) and signal transducer and activator of transcription 3 (STAT3) promotes the hypoxia response. However, their interrelationship in vivo remains poorly defined. The present study investigated the possible relationship between HIF-1 upregulation and STAT3 activation in the rodent kidney in vivo. Activation of HIF-1 and STAT3 was analysed by immunohistochemical staining and western blot analysis in: (i) models of hypoxia-associated kidney injury induced by radiocontrast media or rhabdomyolysis; (ii) following activation of STAT3 by the interleukin (IL)-6-soluble IL-6 receptor complex; or (iii) following HIF-1α stabilization using hypoxic and non-hypoxic stimuli (mimosine, FG-4497, CO, CoCl(2)) and in targeted von Hippel-Lindau-knockout mice. Western blot analysis and immunostaining revealed marked induction of both transcription factors under all conditions tested, suggesting that in vivo STAT3 can trigger HIF and vice versa. Colocalization of HIF-1α and phosphorylated STAT3 was detected in some, but not all, renal cell types, suggesting that in some cells a paracrine mechanism may be responsible for the reciprocal activation of the two transcription factors. Nevertheless, in several cell types spatial concordance was observed under the majority of conditions tested, suggesting that HIF-1 and STAT3 may act as cotranscription factors. These in vivo studies suggest that, in response to renal hypoxic-stress, upregulation of HIF-1 and activation of STAT3 may be both reciprocal and cell type dependent. © 2013 The Authors Clinical and Experimental Pharmacology and Physiology © 2013 Wiley Publishing Asia Pty Ltd.

  14. Zebrafish models of BAG3 myofibrillar myopathy suggest a toxic gain of function leading to BAG3 insufficiency.

    Science.gov (United States)

    Ruparelia, Avnika A; Oorschot, Viola; Vaz, Raquel; Ramm, Georg; Bryson-Richardson, Robert J

    2014-12-01

    Mutations in the co-chaperone Bcl2-associated athanogene 3 (BAG3) can cause myofibrillar myopathy (MFM), a childhood-onset progressive muscle disease, characterized by the formation of protein aggregates and myofibrillar disintegration. In contrast to other MFM-causing proteins, BAG3 has no direct structural role, but regulates autophagy and the degradation of misfolded proteins. To investigate the mechanism of disease in BAG3-related MFM, we expressed wild-type BAG3 or the dominant MFM-causing BAG3 (BAG3(P209L)) in zebrafish. Expression of the mutant protein results in the formation of aggregates that contain wild-type BAG3. Through the stimulation and inhibition of autophagy, we tested the prevailing hypothesis that impaired autophagic function is responsible for the formation of protein aggregates. Contrary to the existing theory, our studies reveal that inhibition of autophagy is not sufficient to induce protein aggregation. Expression of the mutant protein, however, did not induce myofibrillar disintegration and we therefore examined the effect of knocking down Bag3 function. Loss of Bag3 resulted in myofibrillar disintegration, but not in the formation of protein aggregates. Remarkably, BAG3(P209L) is able to rescue the myofibrillar disintegration phenotype, further demonstrating that its function is not impaired. Together, our knockdown and overexpression experiments identify a mechanism whereby BAG3(P209L) aggregates form, gradually reducing the pool of available BAG3, which eventually results in BAG3 insufficiency and myofibrillar disintegration. This mechanism is consistent with the childhood onset and progressive nature of MFM and suggests that reducing aggregation through enhanced degradation or inhibition of nucleation would be an effective therapy for this disease.

  15. Genetic and functional analyses of SHANK2 mutations suggest a multiple hit model of autism spectrum disorders.

    Directory of Open Access Journals (Sweden)

    Claire S Leblond

    2012-02-01

    Full Text Available Autism spectrum disorders (ASD are a heterogeneous group of neurodevelopmental disorders with a complex inheritance pattern. While many rare variants in synaptic proteins have been identified in patients with ASD, little is known about their effects at the synapse and their interactions with other genetic variations. Here, following the discovery of two de novo SHANK2 deletions by the Autism Genome Project, we identified a novel 421 kb de novo SHANK2 deletion in a patient with autism. We then sequenced SHANK2 in 455 patients with ASD and 431 controls and integrated these results with those reported by Berkel et al. 2010 (n = 396 patients and n = 659 controls. We observed a significant enrichment of variants affecting conserved amino acids in 29 of 851 (3.4% patients and in 16 of 1,090 (1.5% controls (P = 0.004, OR = 2.37, 95% CI = 1.23-4.70. In neuronal cell cultures, the variants identified in patients were associated with a reduced synaptic density at dendrites compared to the variants only detected in controls (P = 0.0013. Interestingly, the three patients with de novo SHANK2 deletions also carried inherited CNVs at 15q11-q13 previously associated with neuropsychiatric disorders. In two cases, the nicotinic receptor CHRNA7 was duplicated and in one case the synaptic translation repressor CYFIP1 was deleted. These results strengthen the role of synaptic gene dysfunction in ASD but also highlight the presence of putative modifier genes, which is in keeping with the "multiple hit model" for ASD. A better knowledge of these genetic interactions will be necessary to understand the complex inheritance pattern of ASD.

  16. Expression of venom gene homologs in diverse python tissues suggests a new model for the evolution of snake venom.

    Science.gov (United States)

    Reyes-Velasco, Jacobo; Card, Daren C; Andrew, Audra L; Shaney, Kyle J; Adams, Richard H; Schield, Drew R; Casewell, Nicholas R; Mackessy, Stephen P; Castoe, Todd A

    2015-01-01

    Snake venom gene evolution has been studied intensively over the past several decades, yet most previous studies have lacked the context of complete snake genomes and the full context of gene expression across diverse snake tissues. We took a novel approach to studying snake venom evolution by leveraging the complete genome of the Burmese python, including information from tissue-specific patterns of gene expression. We identified the orthologs of snake venom genes in the python genome, and conducted detailed analysis of gene expression of these venom homologs to identify patterns that differ between snake venom gene families and all other genes. We found that venom gene homologs in the python are expressed in many different tissues outside of oral glands, which illustrates the pitfalls of using transcriptomic data alone to define "venom toxins." We hypothesize that the python may represent an ancestral state prior to major venom development, which is supported by our finding that the expansion of venom gene families is largely restricted to highly venomous caenophidian snakes. Therefore, the python provides insight into biases in which genes were recruited for snake venom systems. Python venom homologs are generally expressed at lower levels, have higher variance among tissues, and are expressed in fewer organs compared with all other python genes. We propose a model for the evolution of snake venoms in which venom genes are recruited preferentially from genes with particular expression profile characteristics, which facilitate a nearly neutral transition toward specialized venom system expression. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Systematic review with meta-analysis: risk factors for non-alcoholic fatty liver disease suggest a shared altered metabolic and cardiovascular profile between lean and obese patients.

    Science.gov (United States)

    Sookoian, S; Pirola, C J

    2017-07-01

    The pathogenesis of non-alcoholic fatty liver disease (NAFLD) is closely associated with the co-occurrence of multiple pathological conditions characterising the metabolic syndrome (MetS), obesity in particular. However, NAFLD also develops in lean subjects, whose risk factors remain poorly defined. We performed a meta-analysis of 15 studies, along with the data pertaining to our own population (n=336 patients). Data from lean (n=1966) and obese (n=5938) patients with NAFLD were analysed; lean (n=9946) and obese (n=6027) subjects without NAFLD served as controls. Relative to the lean non-NAFLD controls, lean patients with NAFLD were older (3.79±0.72 years, P=1.36×10 -6 ) and exhibited the entire spectrum of the MetS risk factors. Specifically, they had a significant (P=10 -10 ) increase in plasma glucose levels (6.44±1.12 mg/dL) and HOMA-IR (0.52±0.094-unit increment), blood lipids (triglycerides: 48.37±3.6, P=10 -10 and total cholesterol: 7.04±3.8, mg/dL, P=4.2×10 -7 ), systolic (5.64±0.7) and diastolic (3.37±0.9) blood pressure (mm Hg), P=10 -10 , and waist circumference (5.88±0.4 cm, P=10 -10 ); values denote difference in means±SE. Nevertheless, the overall alterations in the obese group were much more severe when compared to lean subjects, regardless of the presence of NAFLD. Meta-regression suggested that NAFLD is a modifier of the level of blood lipids. Lean and obese patients with NAFLD share a common altered metabolic and cardiovascular profile. The former, while having normal body weight, showed excess of abdominal adipose tissue as well as other MetS features. © 2017 John Wiley & Sons Ltd.

  18. Low Level Evidence Suggests That Librarian-Led Instruction in Evidence Based Practice is Effective Regardless of Instructional Model

    Directory of Open Access Journals (Sweden)

    Lindsay J. Alcock

    2017-06-01

    studies which included descriptive statistics and many also included inferential statistics intended to show significance. Differences between groups were assessed with parametric measures in 9 studies and non-parametric measures in 15 studies. Good to high statistical significance on at least 1 measurement was achieved in 23 studies. Given the absence of effect sizes, the level of differences between study groups could not be determined. Conclusion – Numerous pedagogical methods are used in librarian-led instruction in evidence based practice. However, there is a paucity of high level evidence and the literature suggests that no instructional method is demonstrated to be more effective than another.

  19. Confirmatory Factor Analysis of WAIS-IV in a Clinical Sample: Examining a Bi-Factor Model

    Directory of Open Access Journals (Sweden)

    Rachel Collinson

    2016-12-01

    Full Text Available There have been a number of studies that have examined the factor structure of the Wechsler Adult Intelligence Scale IV (WAIS-IV using the standardization sample. In this study, we investigate its factor structure on a clinical neuropsychology sample of mixed aetiology. Correlated factor, higher-order and bi-factor models are all tested. Overall, the results suggest that the WAIS-IV will be suitable for use with this population.

  20. Factors influencing creep model equation selection

    International Nuclear Information System (INIS)

    Holdsworth, S.R.; Askins, M.; Baker, A.; Gariboldi, E.; Holmstroem, S.; Klenk, A.; Ringel, M.; Merckling, G.; Sandstrom, R.; Schwienheer, M.; Spigarelli, S.

    2008-01-01

    During the course of the EU-funded Advanced-Creep Thematic Network, ECCC-WG1 reviewed the applicability and effectiveness of a range of model equations to represent the accumulation of creep strain in various engineering alloys. In addition to considering the experience of network members, the ability of several models to describe the deformation characteristics of large single and multi-cast collations of ε(t,T,σ) creep curves have been evaluated in an intensive assessment inter-comparison activity involving three steels, 21/4 CrMo (P22), 9CrMoVNb (Steel-91) and 18Cr13NiMo (Type-316). The choice of the most appropriate creep model equation for a given application depends not only on the high-temperature deformation characteristics of the material under consideration, but also on the characteristics of the dataset, the number of casts for which creep curves are available and on the strain regime for which an analytical representation is required. The paper focuses on the factors which can influence creep model selection and model-fitting approach for multi-source, multi-cast datasets

  1. A 3-factor model for the FACIT-Sp.

    Science.gov (United States)

    Canada, Andrea L; Murphy, Patricia E; Fitchett, George; Peterman, Amy H; Schover, Leslie R

    2008-09-01

    The 12-item Functional Assessment of Chronic Illness Therapy-Spiritual Well-being Scale (FACIT-Sp) is a popular measure of the religious/spiritual (R/S) components of quality of life (QoL) in patients with cancer. The original factor analyses of the FACIT-Sp supported two factors: Meaning/Peace and Faith. Because Meaning suggests a cognitive aspect of R/S and Peace an affective component, we hypothesized a 3-factor solution: Meaning, Peace, and Faith. Participants were 240 long-term female survivors of cancer who completed the FACIT-Sp, the SF-12, and the BSI 18. We used confirmatory factor analysis to compare the 2- and 3-factor models of the FACIT-Sp and subsequently assessed associations between the resulting solutions and QoL domains. Survivors averaged 44 years of age and 10 years post-diagnosis. A 3-factor solution of the FACIT-Sp significantly improved the fit of the model to the data over the original 2-factor structure (Delta chi(2)=72.36, df=2, p<0.001). Further adjustments to the 3-factor model resulted in a final solution with even better goodness-of-fit indices (chi(2)=59.11, df=1, p=0.13, CFI=1.00, SMRM=0.05).The original Meaning/Peace factor controlling for Faith was associated with mental (r=0.63, p<0.000) and physical (r=0.22, p<0.01) health on the SF-12, and the original Faith factor controlling for Meaning/Peace was negatively associated with mental health (r=-0.15, p<0.05). The 3-factor model was more informative. Specifically, using partial correlations, the Peace factor was only related to mental health (r=0.53, p<0.001); Meaning was related to both physical (r=0.18, p<0.01) and mental (r=0.17, p<0.01) health; and Faith was negatively associated with mental health (r=-0.17, p<0.05). The results of this study support a 3-factor solution of the FACIT-Sp. The new solution not only represents a psychometric improvement over the original, but also enables a more detailed examination of the contribution of different dimensions of R/S to QoL. (c

  2. Dimensional Model for Estimating Factors influencing Childhood Obesity: Path Analysis Based Modeling

    Directory of Open Access Journals (Sweden)

    Maryam Kheirollahpour

    2014-01-01

    Full Text Available The main objective of this study is to identify and develop a comprehensive model which estimates and evaluates the overall relations among the factors that lead to weight gain in children by using structural equation modeling. The proposed models in this study explore the connection among the socioeconomic status of the family, parental feeding practice, and physical activity. Six structural models were tested to identify the direct and indirect relationship between the socioeconomic status and parental feeding practice general level of physical activity, and weight status of children. Finally, a comprehensive model was devised to show how these factors relate to each other as well as to the body mass index (BMI of the children simultaneously. Concerning the methodology of the current study, confirmatory factor analysis (CFA was applied to reveal the hidden (secondary effect of socioeconomic factors on feeding practice and ultimately on the weight status of the children and also to determine the degree of model fit. The comprehensive structural model tested in this study suggested that there are significant direct and indirect relationships among variables of interest. Moreover, the results suggest that parental feeding practice and physical activity are mediators in the structural model.

  3. Modelling human factor with Petri nets

    International Nuclear Information System (INIS)

    Bedreaga, Luminita; Constantinescu, Cristina; Guzun, Basarab

    2007-01-01

    The human contribution to risk and safety of nuclear power plant operation can be best understood, assessed and quantified using tools to evaluate human reliability. Human reliability analysis becomes an important part of every probabilistic safety assessment and it is used to demonstrate that nuclear power plants designed with different safety levels are prepared to cope with severe accidents. Human reliability analysis in context of probabilistic safety assessment consists in: identifying human-system interactions important to safety; quantifying probabilities appropriate with these interactions. Nowadays, the complex system functions can be modelled using special techniques centred either on states space adequate to system or on events appropriate to the system. Knowing that complex system model consists in evaluating the likelihood of success, in other words, in evaluating the possible value for that system being in some state, the inductive methods which are based on the system states can be applied also for human reliability modelling. Thus, switching to the system states taking into account the human interactions, the underlying basis of the Petri nets can be successfully applied and the likelihoods appropriate to these states can also derived. The paper presents the manner to assess the human reliability quantification using Petri nets approach. The example processed in the paper is from human reliability documentation without a detailed human factor analysis (qualitative). The obtained results by these two kinds of methods are in good agreement. (authors)

  4. Object recognition in images via a factor graph model

    Science.gov (United States)

    He, Yong; Wang, Long; Wu, Zhaolin; Zhang, Haisu

    2018-04-01

    Object recognition in images suffered from huge search space and uncertain object profile. Recently, the Bag-of- Words methods are utilized to solve these problems, especially the 2-dimension CRF(Conditional Random Field) model. In this paper we suggest the method based on a general and flexible fact graph model, which can catch the long-range correlation in Bag-of-Words by constructing a network learning framework contrasted from lattice in CRF. Furthermore, we explore a parameter learning algorithm based on the gradient descent and Loopy Sum-Product algorithms for the factor graph model. Experimental results on Graz 02 dataset show that, the recognition performance of our method in precision and recall is better than a state-of-art method and the original CRF model, demonstrating the effectiveness of the proposed method.

  5. Proposition Factor Model of World Class Manufacturing in Brazilian Enterprises

    Directory of Open Access Journals (Sweden)

    Paulo Sergio Gonçalves de Oliveira

    2016-05-01

    Full Text Available The present paper aims to develop a model of World Class Manufacturing, to achieve this goal was elaborated a questionnaire with 35 assertive divided in 7 areas suggested by literature review. This questionnaire was send to manufacture specialists, product developers and technician through LinkedIn the participants was select by researchers in discussion groups taking in consideration their experience using the professional profile. About 1000 invite was send to professional from metal-mechanic sector which returned 180 valid questionnaires. The data was analyzed through factor analyses and was obtained 7 constructs, which explained 67% of data variance. The KMO was 0,84, which is considered good for, analyzes purpose. The seventh factor was eliminated because it Cranach’s Alpha was below 0,6 and the remained factor was nominated as: Lean Manufacturing, Human Resources Management to achieve flexibility, Marketing Integration, Costs Reduction and Flexibility.

  6. Improved SVR Model for Multi-Layer Buildup Factor Calculation

    International Nuclear Information System (INIS)

    Trontl, K.; Pevec, D.; Smuc, T.

    2006-01-01

    The accuracy of point kernel method applied in gamma ray dose rate calculations in shielding design and radiation safety analysis is limited by the accuracy of buildup factors used in calculations. Although buildup factors for single-layer shields are well defined and understood, buildup factors for stratified shields represent a complex physical problem that is hard to express in mathematical terms. The traditional approach for expressing buildup factors of multi-layer shields is through semi-empirical formulas obtained by fitting the results of transport theory or Monte Carlo calculations. Such an approach requires an ad-hoc definition of the fitting function and often results with numerous and usually inadequately explained and defined correction factors added to the final empirical formula. Even more, finally obtained formulas are generally limited to a small number of predefined combinations of materials within relatively small range of gamma ray energies and shield thicknesses. Recently, a new approach has been suggested by the authors involving one of machine learning techniques called Support Vector Machines, i.e., Support Vector Regression (SVR). Preliminary investigations performed for double-layer shields revealed great potential of the method, but also pointed out some drawbacks of the developed model, mostly related to the selection of one of the parameters describing the problem (material atomic number), and the method in which the model was designed to evolve during the learning process. It is the aim of this paper to introduce a new parameter (single material buildup factor) that is to replace the existing material atomic number as an input parameter. The comparison of two models generated by different input parameters has been performed. The second goal is to improve the evolution process of learning, i.e., the experimental computational procedure that provides a framework for automated construction of complex regression models of predefined

  7. Model performance evaluation (validation and calibration) in model-based studies of therapeutic interventions for cardiovascular diseases : a review and suggested reporting framework.

    Science.gov (United States)

    Haji Ali Afzali, Hossein; Gray, Jodi; Karnon, Jonathan

    2013-04-01

    Decision analytic models play an increasingly important role in the economic evaluation of health technologies. Given uncertainties around the assumptions used to develop such models, several guidelines have been published to identify and assess 'best practice' in the model development process, including general modelling approach (e.g., time horizon), model structure, input data and model performance evaluation. This paper focuses on model performance evaluation. In the absence of a sufficient level of detail around model performance evaluation, concerns regarding the accuracy of model outputs, and hence the credibility of such models, are frequently raised. Following presentation of its components, a review of the application and reporting of model performance evaluation is presented. Taking cardiovascular disease as an illustrative example, the review investigates the use of face validity, internal validity, external validity, and cross model validity. As a part of the performance evaluation process, model calibration is also discussed and its use in applied studies investigated. The review found that the application and reporting of model performance evaluation across 81 studies of treatment for cardiovascular disease was variable. Cross-model validation was reported in 55 % of the reviewed studies, though the level of detail provided varied considerably. We found that very few studies documented other types of validity, and only 6 % of the reviewed articles reported a calibration process. Considering the above findings, we propose a comprehensive model performance evaluation framework (checklist), informed by a review of best-practice guidelines. This framework provides a basis for more accurate and consistent documentation of model performance evaluation. This will improve the peer review process and the comparability of modelling studies. Recognising the fundamental role of decision analytic models in informing public funding decisions, the proposed

  8. Human factors engineering program review model

    International Nuclear Information System (INIS)

    1994-07-01

    The staff of the Nuclear Regulatory Commission is performing nuclear power plant design certification reviews based on a design process plan that describes the human factors engineering (HFE) program elements that are necessary and sufficient to develop an acceptable detailed design specification and an acceptable implemented design. There are two principal reasons for this approach. First, the initial design certification applications submitted for staff review did not include detailed design information. Second, since human performance literature and industry experiences have shown that many significant human factors issues arise early in the design process, review of the design process activities and results is important to the evaluation of an overall design. However, current regulations and guidance documents do not address the criteria for design process review. Therefore, the HFE Program Review Model (HFE PRM) was developed as a basis for performing design certification reviews that include design process evaluations as well as review of the final design. A central tenet of the HFE PRM is that the HFE aspects of the plant should be developed, designed, and evaluated on the basis of a structured top-down system analysis using accepted HFE principles. The HFE PRM consists of ten component elements. Each element in divided into four sections: Background, Objective, Applicant Submittals, and Review Criteria. This report describes the development of the HFE PRM and gives a detailed description of each HFE review element

  9. Exponentially increasing incidences of cutaneous malignant melanoma in Europe correlate with low personal annual UV doses and suggests 2 major risk factors.

    Science.gov (United States)

    Merrill, Stephen J; Ashrafi, Samira; Subramanian, Madhan; Godar, Dianne E

    2015-01-01

    For several decades the incidence of cutaneous malignant melanoma (CMM) steadily increased in fair-skinned, indoor-working people around the world. Scientists think poor tanning ability resulting in sunburns initiate CMM, but they do not understand why the incidence continues to increase despite the increased use of sunscreens and formulations offering more protection. This paradox, along with lower incidences of CMM in outdoor workers, although they have significantly higher annual UV doses than indoor workers have, perplexes scientists. We found a temporal exponential increase in the CMM incidence indicating second-order reaction kinetics revealing the existence of 2 major risk factors. From epidemiology studies, we know one major risk factor for getting CMM is poor tanning ability and we now propose the other major risk factor may be the Human Papilloma Virus (HPV) because clinicians find β HPVs in over half the biopsies. Moreover, we uncovered yet another paradox; the increasing CMM incidences significantly correlate with decreasing personal annual UV dose, a proxy for low vitamin D3 levels. We also discovered the incidence of CMM significantly increased with decreasing personal annual UV dose from 1960, when it was almost insignificant, to 2000. UV and other DNA-damaging agents can activate viruses, and UV-induced cytokines can hide HPV from immune surveillance, which may explain why CMM also occurs in anatomical locations where the sun does not shine. Thus, we propose the 2 major risk factors for getting CMM are intermittent UV exposures that result in low cutaneous levels of vitamin D3 and possibly viral infection.

  10. Replication and extension of the dual pathway model of disordered eating: The role of fear of negative evaluation, suggestibility, rumination, and self-compassion.

    Science.gov (United States)

    Maraldo, Toni M; Zhou, Wanni; Dowling, Jessica; Vander Wal, Jillon S

    2016-12-01

    The dual pathway model, a theoretical model of eating disorder development, suggests that thin ideal internalization leads to body dissatisfaction which leads to disordered eating via the dual pathways of negative affect and dietary restraint. While the dual pathway model has been a valuable guide for eating disorder prevention, greater knowledge of characteristics that predict thin ideal internalization is needed. The present study replicated and extended the dual pathway model by considering the addition of fear of negative evaluation, suggestibility, rumination, and self-compassion in a sample of community women and female university students. Results showed that fear of negative evaluation and suggestibility predicted thin ideal internalization whereas rumination and self-compassion (inversely) predicted body dissatisfaction. Negative affect was predicted by fear of negative evaluation, rumination, and self-compassion (inversely). The extended model fit the data well in both samples. Analogue and longitudinal study of these constructs is warranted in future research. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Model of separated form factors for unilamellar vesicles

    International Nuclear Information System (INIS)

    Kiselev, M.A.; Aksenov, V.L.; Lesieur, P.; Lombardo, D.; Kiselev, A.M.

    2001-01-01

    A new model of separated form factors is proposed for the evaluation of small-angle neutron scattering curves from large unilamellar vesicles. The validity of the model was checked via comparison with the model of a hollow sphere. The model of separated form factors and the hollow sphere model give a reasonable agreement in the evaluation of vesicle parameters

  12. The Zygosaccharomyces bailii transcription factor Haa1 is required for acetic acid and copper stress responses suggesting subfunctionalization of the ancestral bifunctional protein Haa1/Cup2.

    Science.gov (United States)

    Palma, Margarida; Dias, Paulo Jorge; Roque, Filipa de Canaveira; Luzia, Laura; Guerreiro, Joana Fernandes; Sá-Correia, Isabel

    2017-01-13

    The food spoilage yeast species Zygosaccharomyces bailii exhibits an extraordinary capacity to tolerate weak acids, in particular acetic acid. In Saccharomyces cerevisiae, the transcription factor Haa1 (ScHaa1) is considered the main player in genomic expression reprogramming in response to acetic acid stress, but the role of its homologue in Z. bailii (ZbHaa1) is unknown. In this study it is demonstrated that ZbHaa1 is a ScHaa1 functional homologue by rescuing the acetic acid susceptibility phenotype of S. cerevisiae haa1Δ. The disruption of ZbHAA1 in Z. bailii IST302 and the expression of an extra ZbHAA1 copy confirmed ZbHAA1 as a determinant of acetic acid tolerance. ZbHaa1 was found to be required for acetic acid stress-induced transcriptional activation of Z. bailii genes homologous to ScHaa1-target genes. An evolutionary analysis of the Haa1 homologues identified in 28 Saccharomycetaceae species genome sequences, including Z bailii, was carried out using phylogenetic and gene neighbourhood approaches. Consistent with previous studies, this analysis revealed a group containing pre-whole genome duplication species Haa1/Cup2 single orthologues, including ZbHaa1, and two groups containing either Haa1 or Cup2 orthologues from post-whole genome duplication species. S. cerevisiae Cup2 (alias Ace1) is a transcription factor involved in response and tolerance to copper stress. Taken together, these observations led us to hypothesize and demonstrate that ZbHaa1 is also involved in copper-induced transcriptional regulation and copper tolerance. The transcription factor ZbHaa1 is required for adaptive response and tolerance to both acetic acid and copper stresses. The subfunctionalization of the single ancestral Haa1/Cup2 orthologue that originated Haa1 and Cup2 paralogues after whole genome duplication is proposed.

  13. The animal model determines the results of Aeromonas virulence factors

    Directory of Open Access Journals (Sweden)

    Alejandro Romero

    2016-10-01

    Full Text Available The selection of an experimental animal model is of great importance in the study of bacterial virulence factors. Here, a bath infection of zebrafish larvae is proposed as an alternative model to study the virulence factors of A. hydrophila. Intraperitoneal infections in mice and trout were compared with bath infections in zebrafish larvae using specific mutants. The great advantage of this model is that bath immersion mimics the natural route of infection, and injury to the tail also provides a natural portal of entry for the bacteria. The implication of T3SS in the virulence of A. hydrophila was analysed using the AH-1::aopB mutant. This mutant was less virulent than the wild-type strain when inoculated into zebrafish larvae, as described in other vertebrates. However, the zebrafish model exhibited slight differences in mortality kinetics only observed using invertebrate models. Infections using the mutant AH-1∆vapA lacking the gene coding for the surface S-layer suggested that this protein was not totally necessary to the bacteria once it was inside the host, but it contributed to the inflammatory response. Only when healthy zebrafish larvae were infected did the mutant produce less mortality than the wild type. Variations between models were evidenced using the AH-1∆rmlB, which lacks the O-antigen lipopolysaccharide (LPS, and the AH-1∆wahD, which lacks the O-antigen LPS and part of the LPS outer-core. Both mutants showed decreased mortality in all of the animal models, but the differences between them were only observed in injured zebrafish larvae, suggesting that residues from the LPS outer core must be important for virulence. The greatest differences were observed using the AH-1ΔFlaB-J (lacking polar flagella and unable to swim and the AH-1::motX (non-motile but producing flagella. They were as pathogenic as the wild-type strain when injected into mice and trout, but no mortalities were registered in zebrafish larvae. This study

  14. Clinical application of the five-factor model.

    Science.gov (United States)

    Widiger, Thomas A; Presnall, Jennifer Ruth

    2013-12-01

    The Five-Factor Model (FFM) has become the predominant dimensional model of general personality structure. The purpose of this paper is to suggest a clinical application. A substantial body of research indicates that the personality disorders included within the American Psychiatric Association's (APA) Diagnostic and Statistical Manual of Mental Disorders (DSM) can be understood as extreme and/or maladaptive variants of the FFM (the acronym "DSM" refers to any particular edition of the APA DSM). In addition, the current proposal for the forthcoming fifth edition of the DSM (i.e., DSM-5) is shifting closely toward an FFM dimensional trait model of personality disorder. Advantages of this shifting conceptualization are discussed, including treatment planning. © 2012 Wiley Periodicals, Inc.

  15. Preliminary Finnish Measures of Eating Competence Suggest Association with Health-Promoting Eating Patterns and Related Psychobehavioral Factors in 10?17 Year Old Adolescents

    OpenAIRE

    Tanja, Tilles-Tirkkonen; Outi, Nuutinen; Sakari, Suominen; Jarmo, Liukkonen; Kaisa, Poutanen; Leila, Karhunen

    2015-01-01

    Eating competence is an attitudinal and behavioral concept, based on The Satter Eating Competence Model. In adults, it has been shown to be associated with a higher quality of diet. Eating competence or its association with the quality of diet has not been studied in adolescents. The aim of the current study was to explore the utility of using a preliminary Finnish translation of the ecSI 2.0 for evaluating presumed eating competence and its association with food selection, mea...

  16. Open to Suggestion.

    Science.gov (United States)

    Journal of Reading, 1987

    1987-01-01

    Offers (1) suggestions for improving college students' study skills; (2) a system for keeping track of parent, teacher, and community contacts; (3) suggestions for motivating students using tic tac toe; (4) suggestions for using etymology to improve word retention; (5) a word search grid; and (6) suggestions for using postcards in remedial reading…

  17. Model of a ternary complex between activated factor VII, tissue factor and factor IX.

    Science.gov (United States)

    Chen, Shu-wen W; Pellequer, Jean-Luc; Schved, Jean-François; Giansily-Blaizot, Muriel

    2002-07-01

    Upon binding to tissue factor, FVIIa triggers coagulation by activating vitamin K-dependent zymogens, factor IX (FIX) and factor X (FX). To understand recognition mechanisms in the initiation step of the coagulation cascade, we present a three-dimensional model of the ternary complex between FVIIa:TF:FIX. This model was built using a full-space search algorithm in combination with computational graphics. With the known crystallographic complex FVIIa:TF kept fixed, the FIX docking was performed first with FIX Gla-EGF1 domains, followed by the FIX protease/EGF2 domains. Because the FIXa crystal structure lacks electron density for the Gla domain, we constructed a chimeric FIX molecule that contains the Gla-EGF1 domains of FVIIa and the EGF2-protease domains of FIXa. The FVIIa:TF:FIX complex has been extensively challenged against experimental data including site-directed mutagenesis, inhibitory peptide data, haemophilia B database mutations, inhibitor antibodies and a novel exosite binding inhibitor peptide. This FVIIa:TF:FIX complex provides a powerful tool to study the regulation of FVIIa production and presents new avenues for developing therapeutic inhibitory compounds of FVIIa:TF:substrate complex.

  18. Reformulation of Crop and Management Factor in ANSWERS Model

    Directory of Open Access Journals (Sweden)

    Yayat Hidayat

    2008-05-01

    Full Text Available Crop and management factor value is significantly corelated with outputs of ANSWERS model especially on soil erosion. Using daily crop and management factors (daily C factors, the ANSWERS model performs well in predicting soil erosion which is showed by determination coeffient (R2 = 0.89, model efficiency (0.86, and average of percentage model deviations (24.1%. Whereas using USLE C factor (2 cropping systems, predicted is much higher than measured soil erosion (over estimate. Output of the model is not statisfy; it is represented by model coefficient (0.40 and average of percentage model deviations (63.6%.

  19. Using exploratory regression to identify optimal driving factors for cellular automaton modeling of land use change.

    Science.gov (United States)

    Feng, Yongjiu; Tong, Xiaohua

    2017-09-22

    Defining transition rules is an important issue in cellular automaton (CA)-based land use modeling because these models incorporate highly correlated driving factors. Multicollinearity among correlated driving factors may produce negative effects that must be eliminated from the modeling. Using exploratory regression under pre-defined criteria, we identified all possible combinations of factors from the candidate factors affecting land use change. Three combinations that incorporate five driving factors meeting pre-defined criteria were assessed. With the selected combinations of factors, three logistic regression-based CA models were built to simulate dynamic land use change in Shanghai, China, from 2000 to 2015. For comparative purposes, a CA model with all candidate factors was also applied to simulate the land use change. Simulations using three CA models with multicollinearity eliminated performed better (with accuracy improvements about 3.6%) than the model incorporating all candidate factors. Our results showed that not all candidate factors are necessary for accurate CA modeling and the simulations were not sensitive to changes in statistically non-significant driving factors. We conclude that exploratory regression is an effective method to search for the optimal combinations of driving factors, leading to better land use change models that are devoid of multicollinearity. We suggest identification of dominant factors and elimination of multicollinearity before building land change models, making it possible to simulate more realistic outcomes.

  20. Inhibition of the transcription factor c-Jun by the MAPK family, and not the NF-κB pathway, suggests that peanut extract has anti-inflammatory properties.

    Science.gov (United States)

    Catalán, Úrsula; Fernández-Castillejo, Sara; Anglès, Neus; Morelló, Jose Ramón; Yebras, Martí; Solà, Rosa

    2012-10-01

    Tumor necrosis factor-α (TNF-α) is involved in inflammatory responses in atherosclerosis. We propose an in vitro cellular assay to evaluate the anti-inflammatory mechanisms of potential modifiers such as food extracts. In the current model we assessed an anti-inflammatory effect of polyphenol-rich peanut extract in lipopolysaccharide (LPS)-induced THP-1 monocytes. THP-1 monocytes were incubated with peanut extract (5, 25, 50 and 100 μg/mL) consisting of 39% flavonols, 37% flavanols and 24% phenolic acid (or BAY 11-7082 (5 μM) as experiment control) for 1 h and then stimulated with LPS (500 ng/mL) for 4 h. Cytotoxicity was measured as lactate dehydrogenase (LDH) activity release. NF-κB and MAPK family were determined by TransAm kit while TNF-α mRNA levels and its mRNA stability by RT-PCR. Intra- and extracellular TNF-α protein was measured by ELISA, and TNF-α converting enzyme (TACE) activity by a fluorimetric assay. Peanut extract inhibited the maximal LPS-induced extracellular TNF-α protein secretion by 18%, 29% and 47% at 25, 50 and 100 μg/mL, respectively (P<0.05). LPS stimulation revealed that 85% of TNF-α was released extracellularly while 15% remained intracellular. Peanut extract did not modify NF-κB but, instead, reduced c-Jun transcription factor activity (P<0.05), decreased TNF-α mRNA (albeit non-significantly) and had no effect on mRNA stability and TACE activity. Polyphenol-rich peanut extract reduces extracellular TNF-α protein by inhibiting c-Jun transcription factor from MAPK family, suggesting an anti-inflammatory effect. The proposed THP-1 monocyte model could be used to assess food extract impact (site and size effects) on the inflammation pathway. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Suicidality and interrogative suggestibility.

    Science.gov (United States)

    Pritchard-Boone, Lea; Range, Lillian M

    2005-01-01

    All people are subject to memory suggestibility, but suicidal individuals may be especially so. The link between suicidality and suggestibility is unclear given mixed findings and methodological weaknesses of past research. To test the link between suicidality and interrogative suggestibility, 149 undergraduates answered questions about suicidal thoughts and reasons for living, and participated in a direct suggestibility procedure. As expected, suggestibility correlated with suicidality but accounted for little overall variance (4%). Mental health professionals might be able to take advantage of client suggestibility by directly telling suicidal persons to refrain from suicidal thoughts or actions.

  2. Transcriptional, translational, and physiological signatures of undernourished honey bees (Apis mellifera) suggest a role for hormonal factors in hypopharyngeal gland degradation.

    Science.gov (United States)

    Corby-Harris, Vanessa; Meador, Charlotte A D; Snyder, Lucy A; Schwan, Melissa R; Maes, Patrick; Jones, Beryl M; Walton, Alexander; Anderson, Kirk E

    2016-02-01

    Honey bee colonies function as a superorganism, where facultatively sterile female workers perform various tasks that support the hive. Nurse workers undergo numerous anatomical and physiological changes in preparation for brood rearing, including the growth of hypopharyngeal glands (HGs). These glands produce the major protein fraction of a protein- and lipid-rich jelly used to sustain developing larvae. Pollen intake is positively correlated with HG growth, but growth in the first three days is similar regardless of diet, suggesting that initial growth is a pre-determined process while later HG development depends on nutrient availability during a critical window in early adulthood (>3 d). It is unclear whether the resultant size differences in nurse HG are simply due to growth arrest or active degradation of the tissue. To determine what processes cause such differences in HG size, we catalogued the differential expression of both gene transcripts and proteins in the HGs of 8 d old bees that were fed diets containing pollen or no pollen. 3438 genes and 367 proteins were differentially regulated due to nutrition. Of the genes and proteins differentially expressed, undernourished bees exhibited more gene and protein up-regulation compared to well-nourished bees, with the affected processes including salivary gland apoptosis, oogenesis, and hormone signaling. Protein secretion was virtually the only process up-regulated in well-nourished bees. Further assays demonstrated that inhibition of ultraspiracle, one component of the ecdysteroid receptor, in the fat body caused larger HGs. Undernourished bees also had higher acid phosphatase activity, a physiological marker of cell death, compared to well-nourished bees. These results support a connection between poor nutrition, hormonal signaling, and HG degradation. Published by Elsevier Ltd.

  3. Change management in Iranian hospitals: social factors model

    Directory of Open Access Journals (Sweden)

    B. Delgoshaei

    2012-02-01

    Full Text Available Background: Continuous change in the complex health care environments is a major challenge for administrative managers. This study aimed to design a change model to facilitate change implementation in the Iranian hospitals. Methods: This is a descriptive and comparative study. The data were collected through library search and in-depth interview with 15 hospital managers. Nine well-established change theories developed by Lewin, Action Research, Kotter, Ackerman- Anderson and Anderson, Prosci , Kilman, Beer, Continuum, and Gelicher were compared. Common denominators of the theories were identified and tabulated. Experienced hospital managers’ suggestions about social factors were acquired. The initial model was designed and validated using the Delphi Technique. Results: The majority of the selected change models emphasize the significance of social factors in change implementation such as effective communication, organizational climate and culture, and leadership. The results from the interviews indicate that low readiness to change, lack of confidence (or trust for change, and autocratic leadership style ,and poor communication could hinder the change process. Conclusion: Based on the model developed in the study, effective communication, readiness of employees, and a contingency leadership/management combined could lead to successful implementation of change in the hospital.

  4. PENGUJIAN FAMA-FRENCH THREE-FACTOR MODEL DI INDONESIA

    Directory of Open Access Journals (Sweden)

    Damar Hardianto

    2017-03-01

    Full Text Available This study empirically examined the Fama-French three factor model of stock returnsfor Indonesia over the period 2000-2004. We found evidence for pervasive market, size, andbook-to-market factors in Indonesian stock returns. We found that cross-sectional mean returnswere explained by exposures to these three factors, and not by the market factor alone. Theempirical results were reasonably consistent with the Fama-French three factor model.

  5. Genes Linked to Endometriosis by GWAS Are Integral to Cytoskeleton Regulation and Suggests That Mesothelial Barrier Homeostasis Is a Factor in the Pathogenesis of Endometriosis.

    Science.gov (United States)

    Albertsen, Hans M; Ward, Kenneth

    2017-06-01

    Endometriosis, defined by the presence of ectopic endometrial lesions, is a common disease in reproductive-age women that profoundly affects patients' quality of life. Various pathogenic models have been proposed, but the origin of endometriosis remains elusive. In this article, we propose that the mesothelial barrier, which protects the underlying stroma from endometrial transplants present in retrograde menstrual fluid, can be compromised by activation of the epithelial to mesenchymal transition (EMT) repair mechanism that lead to temporary loss of barrier integrity. Absent of the mesothelial barrier, endometrial cells can more readily adhere to the underlying peritoneal stroma and establish endometrial lesions. The hypothesis is based on the clinical and experimental observations that correlate the location of endometrial lesions with areas of mesothelial damage, together with genetic evidence that 4 genes associated with endometriosis are direct regulators of the actin-cytoskeleton, which coordinates mesothelial barrier integrity. It supports past observations that implicate the peritoneum in the pathogenesis of endometriosis and unifies previously disparate theories that endometriosis may be triggered by infection, mechanical damage, and inflammation since each of these mechanisms can induce EMT in the mesothelium. If the hypothesis is correct, inhibition of EMT in the mesothelial barrier provides a novel paradigm for the prevention and treatment of endometriosis.

  6. 吉林省对朝边贸制约因素及政策建议%Jilin Province, Restricting Factors and Policy Suggestions toward the Border Trade

    Institute of Scientific and Technical Information of China (English)

    刘越; 赵慧; 杨奉宇

    2014-01-01

    在中朝经贸合作中,吉林省凭借与朝接壤的独特地缘优势,发挥着重要作用。虽然吉林省边境贸易发展呈递增态势,但对朝边贸规模远远滞后于辽宁省,一是对朝贸易总额占比,吉林为25-35%,辽宁为65-75%;二是对朝贸易额,2009年(由于国际社会对朝鲜经济制裁,海关未公布2010年以后数据)吉林为7.53亿美元,辽宁为23.11亿美元。调查了解发现,2005年前一般是丹东地区企业落户吉林省各口岸城市设立边贸公司分支机构,而现在多家企业注销本地公司而直接前往丹东地区。本地企业外流,说明本地涉外软环境建设滞后,导致地区经济财政税收均有所损失。为此进行了深入调研,建议吉林省把发展边贸与振兴吉林老工业基地有效地结合,完善政策,加大力度,实现突破,促进我省边境贸易持续快速发展。%In the economic and trade cooperation between China and DPRK, Jilin province with unique geographical advantage and toward the border, and plays an important role. Although the border trade in Jilin province development shows an increasing trend, but towards the border trade scale lags far behind in Liaoning Province, one is toward the total trade accounted for more than, Jilin 25-35%, Liaoning 65-75%; two is toward the trade volume in 2009 (due to the international society of economic sanctions on North Korea, the customs of unpublished data after 2010) of Jilin $753000000, $2311000000 in Liaoning. Investigation found that in 2005 before the general is the Dandong area enterprise located in the port city of Jilin province to set up branches border trade company, and now the cancellation of Local Company many enterprises and go directly to the Dandong area. Local enterprises outlfow, illustrate the local lag foreign soft environment construction, lead to tax had regional economic ifnancial loss. Therefore, in-depth research, suggestions of Jilin

  7. Modelling impulsive factors for electronics and restaurant coupons’ e-store display

    Science.gov (United States)

    Ariningsih, P. K.; Nainggolan, M.; Sandy, I. A.

    2018-04-01

    In many times, the increment of e-store visitors does not followed by sales increment. Most purchases through e-commerce are impulsive buying, however only small amount of study is available to understand impulsive factors of e-store display. This paper suggests a preliminary concept on understanding the impulsive factors in Electronics and Restaurant Coupons e-store display, which are two among few popular group products sold through e-commerce. By conducting literature study and survey, 31 attributes were identified as impulsive factors in electronics e-store display and 20 attributes were identified as impulsive factors for restaurant coupon e-store. The attributes were then grouped into comprehensive impulsive factors by factor analysis. Each group of impulsive attributes were generated into 3 factors. Accessibility Factors and Trust Factors appeared for each group products. The other factors are Internal Factors for electronics e-store and Marketing factors for restaurant coupons e-store. Structural Equation Model of the impulsive factors was developed for each type of e-store, which stated the covariance between Trust Factors and Accessibility Factors. Based on preliminary model, Internal Factor and Trust Factor are influencing impulsive buying in electronics store. Special factor for electronics e-store is Internal Factor, while for restaurant coupons e-store is Marketing Factor.

  8. Cloud Computing Adoption Business Model Factors: Does Enterprise Size Matter?

    OpenAIRE

    Bogataj Habjan, Kristina; Pucihar, Andreja

    2017-01-01

    This paper presents the results of research investigating the impact of business model factors on cloud computing adoption. The introduced research model consists of 40 cloud computing business model factors, grouped into eight factor groups. Their impact and importance for cloud computing adoption were investigated among enterpirses in Slovenia. Furthermore, differences in opinion according to enterprise size were investigated. Research results show no statistically significant impacts of in...

  9. Structural models of zebrafish (Danio rerio NOD1 and NOD2 NACHT domains suggest differential ATP binding orientations: insights from computational modeling, docking and molecular dynamics simulations.

    Directory of Open Access Journals (Sweden)

    Jitendra Maharana

    Full Text Available Nucleotide-binding oligomerization domain-containing protein 1 (NOD1 and NOD2 are cytosolic pattern recognition receptors playing pivotal roles in innate immune signaling. NOD1 and NOD2 recognize bacterial peptidoglycan derivatives iE-DAP and MDP, respectively and undergoes conformational alternation and ATP-dependent self-oligomerization of NACHT domain followed by downstream signaling. Lack of structural adequacy of NACHT domain confines our understanding about the NOD-mediated signaling mechanism. Here, we predicted the structure of NACHT domain of both NOD1 and NOD2 from model organism zebrafish (Danio rerio using computational methods. Our study highlighted the differential ATP binding modes in NOD1 and NOD2. In NOD1, γ-phosphate of ATP faced toward the central nucleotide binding cavity like NLRC4, whereas in NOD2 the cavity was occupied by adenine moiety. The conserved 'Lysine' at Walker A formed hydrogen bonds (H-bonds and Aspartic acid (Walker B formed electrostatic interaction with ATP. At Sensor 1, Arg328 of NOD1 exhibited an H-bond with ATP, whereas corresponding Arg404 of NOD2 did not. 'Proline' of GxP motif (Pro386 of NOD1 and Pro464 of NOD2 interacted with adenine moiety and His511 at Sensor 2 of NOD1 interacted with γ-phosphate group of ATP. In contrast, His579 of NOD2 interacted with the adenine moiety having a relatively inverted orientation. Our findings are well supplemented with the molecular interaction of ATP with NLRC4, and consistent with mutagenesis data reported for human, which indicates evolutionary shared NOD signaling mechanism. Together, this study provides novel insights into ATP binding mechanism, and highlights the differential ATP binding modes in zebrafish NOD1 and NOD2.

  10. Assessment of slip factor models at off-design condition

    International Nuclear Information System (INIS)

    Yoon, Sung Ho; Baek, Je Hyun

    2000-01-01

    Slip factor is defined as an empirical factor being multiplied to theoretical energy transfer for the estimation of real work input of a centrifugal compressor. Researchers have tried to develop a simple empirical model, for a century, to predict a slip factor. However most these models were developed on the condition of design point assuming inviscid flow. So these models often fail to predict a correct slip factor at off-design condition. In this study, we summarized various slip factor models and compared these models with experimental and numerical data at off-design condition. As a result of this study, Wiesner's and Paeng and Chung's models are applicable for radial impeller, but all the models are not suitable for backswept impeller. Finally, the essential avenues for future study is discussed

  11. Expertly validated models and phylogenetically-controlled analysis suggests responses to climate change are related to species traits in the order lagomorpha.

    Directory of Open Access Journals (Sweden)

    Katie Leach

    Full Text Available Climate change during the past five decades has impacted significantly on natural ecosystems, and the rate of current climate change is of great concern among conservation biologists. Species Distribution Models (SDMs have been used widely to project changes in species' bioclimatic envelopes under future climate scenarios. Here, we aimed to advance this technique by assessing future changes in the bioclimatic envelopes of an entire mammalian order, the Lagomorpha, using a novel framework for model validation based jointly on subjective expert evaluation and objective model evaluation statistics. SDMs were built using climatic, topographical, and habitat variables for all 87 lagomorph species under past and current climate scenarios. Expert evaluation and Kappa values were used to validate past and current models and only those deemed 'modellable' within our framework were projected under future climate scenarios (58 species. Phylogenetically-controlled regressions were used to test whether species traits correlated with predicted responses to climate change. Climate change is likely to impact more than two-thirds of lagomorph species, with leporids (rabbits, hares, and jackrabbits likely to undertake poleward shifts with little overall change in range extent, whilst pikas are likely to show extreme shifts to higher altitudes associated with marked range declines, including the likely extinction of Kozlov's Pika (Ochotona koslowi. Smaller-bodied species were more likely to exhibit range contractions and elevational increases, but showing little poleward movement, and fecund species were more likely to shift latitudinally and elevationally. Our results suggest that species traits may be important indicators of future climate change and we believe multi-species approaches, as demonstrated here, are likely to lead to more effective mitigation measures and conservation management. We strongly advocate studies minimising data gaps in our knowledge of

  12. Modelling of Supercapacitors: Factors Influencing Performance

    OpenAIRE

    Kroupa, M; Offer, GJ; Kosek, J

    2016-01-01

    The utilizable capacitance of Electrochemical Double Layer Capacitors (EDLCs) is a function of the frequency at which they are operated and this is strongly dependent on the construction and physical parameters of the device. We simulate the dynamic behavior of an EDLC using a spatially resolved model based on the porous electrode theory. The model of Verbrugge and Liu (J. Electrochem. Soc. 152, D79 (2005)) was extended with a dimension describing the transport into the carbon particle pores....

  13. The α-fetoprotein knock-out mouse model suggests that parental behavior is sexually differentiated under the influence of prenatal estradiol

    Science.gov (United States)

    Keller, Matthieu; Pawluski, Jodi L.; Brock, Olivier; Douhard, Quentin; Bakker, Julie

    2010-01-01

    In rodent species, sexual differentiation of the brain for many reproductive processes depends largely on estradiol. This was recently confirmed again by using the α-fetoprotein knockout (AFP-KO) mouse model, which lacks the protective actions of α-fetoprotein against maternal estradiol and as a result represents a good model to determine the contribution of prenatal estradiol to the sexual differentiation of the brain and behavior. Female AFP-KO mice were defeminized and masculinized with regard to their neuroendocrine responses as well as sexual behavior. Since parental behavior is also strongly sexually differentiated in mice, we used the AFP-KO mouse model here to ask whether parental responses are differentiated prenatally under the influence of estradiol. It was found that AFP-KO females showed longer latencies to retrieve pups to the nest and also exhibited lower levels of crouching over the pups in the nest in comparison to WT females. In fact, they resembled males (WT and AFP-KO). Other measures of maternal behavior, for example the incidence of infanticide, tended to be higher in AFP-KO females than in WT females but this increase failed to reach statistical significance. The deficits observed in parental behavior of AFP-KO females could not be explained by any changes in olfactory function, novelty recognition or anxiety. Thus our results suggest that prenatal estradiol defeminizes the parental brain in mice. PMID:20109458

  14. Disentangling unisensory from fusion effects in the attentional modulation of McGurk effects: a Bayesian modeling study suggests that fusion is attention-dependent

    DEFF Research Database (Denmark)

    Schwartz, Jean-Luc; Tiiippana, Kaisa; Andersen, Tobias

    2010-01-01

    The McGurk effect has been shown to be modulated by attention. However, it remains unclear whether attentional effects are due to changes in unisensory processing or in the fusion mechanism. In this paper, we used published experimental data showing that distraction of visual attention weakens th...... Selection criterion. Our findings suggest that distraction of visual attention affects fusion by decreasing the weight of the visual input.......The McGurk effect has been shown to be modulated by attention. However, it remains unclear whether attentional effects are due to changes in unisensory processing or in the fusion mechanism. In this paper, we used published experimental data showing that distraction of visual attention weakens...... the McGurk effect, to fit either the Fuzzy Logical Model of Perception (FLMP) in which the fusion mechanism is fixed, or a variant of it in which the fusion mechanism could be varied depending on attention. The latter model was associated with a larger likelihood when assessed with a Bayesian Model...

  15. An Extremely Massive White Dwarf of the Symbiotic Classical Nova V407 Cyg as Suggested by the RS Oph and U SCO Models

    Directory of Open Access Journals (Sweden)

    Hachisu I.

    2012-06-01

    Full Text Available We have analyzed the optical light curve of the symbiotic star V407 Cyg that underwent a classical nova outburst in 2010 March. Being guided by a supersoft X-ray phase observed during days 20-40 after the nova outburst, we are able to reproduce the light curve during a very early phase of the nova outburst. Our model consists of an outbursting white dwarf and an extended equatorial disk. An extremely massive white dwarf of 1.35-1.37 M⊙ is suggested. the optical light curve is also consistent with a sharp drop 47 days after the outburst, which is the end of hydrogen shell-burning on the white dwarf. Although the extremely massive white dwarf is favourable to the interpretation that V407 Cyg is a recurrent nova, enrichment of heavy elements in the ejecta suggests that the white dwarf is eroded and, as a result, its mass is not increasing. Therefore, V407 Cyg may not explode as a Type Ia supernova even if it is a carbon-oxygen white dwarf.

  16. The modeled structure of the RNA dependent RNA polymerase of GBV-C Virus suggests a role for motif E in Flaviviridae RNA polymerases

    Directory of Open Access Journals (Sweden)

    Dutartre Hélène

    2005-10-01

    Full Text Available Abstract Background The Flaviviridae virus family includes major human and animal pathogens. The RNA dependent RNA polymerase (RdRp plays a central role in the replication process, and thus is a validated target for antiviral drugs. Despite the increasing structural and enzymatic characterization of viral RdRps, detailed molecular replication mechanisms remain unclear. The hepatitis C virus (HCV is a major human pathogen difficult to study in cultured cells. The bovine viral diarrhea virus (BVDV is often used as a surrogate model to screen antiviral drugs against HCV. The structure of BVDV RdRp has been recently published. It presents several differences relative to HCV RdRp. These differences raise questions about the relevance of BVDV as a surrogate model, and cast novel interest on the "GB" virus C (GBV-C. Indeed, GBV-C is genetically closer to HCV than BVDV, and can lead to productive infection of cultured cells. There is no structural data for the GBV-C RdRp yet. Results We show in this study that the GBV-C RdRp is closest to the HCV RdRp. We report a 3D model of the GBV-C RdRp, developed using sequence-to-structure threading and comparative modeling based on the atomic coordinates of the HCV RdRp structure. Analysis of the predicted structural features in the phylogenetic context of the RNA polymerase family allows rationalizing most of the experimental data available. Both available structures and our model are explored to examine the catalytic cleft, allosteric and substrate binding sites. Conclusion Computational methods were used to infer evolutionary relationships and to predict the structure of a viral RNA polymerase. Docking a GTP molecule into the structure allows defining a GTP binding pocket in the GBV-C RdRp, such as that of BVDV. The resulting model suggests a new proposition for the mechanism of RNA synthesis, and may prove useful to design new experiments to implement our knowledge on the initiation mechanism of RNA

  17. Hierarchical and coupling model of factors influencing vessel traffic flow.

    Directory of Open Access Journals (Sweden)

    Zhao Liu

    Full Text Available Understanding the characteristics of vessel traffic flow is crucial in maintaining navigation safety, efficiency, and overall waterway transportation management. Factors influencing vessel traffic flow possess diverse features such as hierarchy, uncertainty, nonlinearity, complexity, and interdependency. To reveal the impact mechanism of the factors influencing vessel traffic flow, a hierarchical model and a coupling model are proposed in this study based on the interpretative structural modeling method. The hierarchical model explains the hierarchies and relationships of the factors using a graph. The coupling model provides a quantitative method that explores interaction effects of factors using a coupling coefficient. The coupling coefficient is obtained by determining the quantitative indicators of the factors and their weights. Thereafter, the data obtained from Port of Tianjin is used to verify the proposed coupling model. The results show that the hierarchical model of the factors influencing vessel traffic flow can explain the level, structure, and interaction effect of the factors; the coupling model is efficient in analyzing factors influencing traffic volumes. The proposed method can be used for analyzing increases in vessel traffic flow in waterway transportation system.

  18. Hierarchical and coupling model of factors influencing vessel traffic flow.

    Science.gov (United States)

    Liu, Zhao; Liu, Jingxian; Li, Huanhuan; Li, Zongzhi; Tan, Zhirong; Liu, Ryan Wen; Liu, Yi

    2017-01-01

    Understanding the characteristics of vessel traffic flow is crucial in maintaining navigation safety, efficiency, and overall waterway transportation management. Factors influencing vessel traffic flow possess diverse features such as hierarchy, uncertainty, nonlinearity, complexity, and interdependency. To reveal the impact mechanism of the factors influencing vessel traffic flow, a hierarchical model and a coupling model are proposed in this study based on the interpretative structural modeling method. The hierarchical model explains the hierarchies and relationships of the factors using a graph. The coupling model provides a quantitative method that explores interaction effects of factors using a coupling coefficient. The coupling coefficient is obtained by determining the quantitative indicators of the factors and their weights. Thereafter, the data obtained from Port of Tianjin is used to verify the proposed coupling model. The results show that the hierarchical model of the factors influencing vessel traffic flow can explain the level, structure, and interaction effect of the factors; the coupling model is efficient in analyzing factors influencing traffic volumes. The proposed method can be used for analyzing increases in vessel traffic flow in waterway transportation system.

  19. Chou-Yang model and PHI form factor

    Energy Technology Data Exchange (ETDEWEB)

    Fazal-e-Aleem; Saleem, M.; Rafique, M.

    1988-03-01

    By using the deduced differential cross-section data for PHIp elastic scattering at 175 GeV/c in the Chou-Yang model, the PHI form factor has been computed and parametrized. Then in conjunction with the proton form factor this form factor is used in the pristine Chou-Yang model to obtain differential cross-section data at Fermilab energies. The theoretical results agree with the experimental measurements, endorsing the conjecture that the hadronic form factor of neutral particle is proportional to its magnetic form factor.

  20. Suggestive Objects at Work

    DEFF Research Database (Denmark)

    Ratner, Helene Gad

    2009-01-01

    In Western secular societies, spiritual life is no longer limited to classical religious institutions but can also be found at workplace organizations. While spirituality is conventionally understood as a subjective and internal process, this paper proposes the concept of ‘suggestive objects......’, constructed by combining insights from Gabriel Tarde's sociology with Bruno Latour's actor-network theory, to theorize the material dimension of organizational spirituality. The sacred in organizations arises not from the internalization of collective values but through the establishment of material...... scaffolding. This has deep implications for our understanding of the sacred, including a better appreciation of the way that suggestive objects make the sacred durable, the way they organize it....

  1. 3D mathematical modeling of glioblastoma suggests that transdifferentiated vascular endothelial cells mediate resistance to current standard-of-care therapy

    Science.gov (United States)

    Yan, Huaming; Romero-López, Mónica; Benitez, Lesly I.; Di, Kaijun; Frieboes, Hermann B.; Hughes, Christopher C. W.; Bota, Daniela A.; Lowengrub, John S.

    2017-01-01

    Glioblastoma (GBM), the most aggressive brain tumor in human patients, is decidedly heterogeneous and highly vascularized. Glioma stem/initiating cells (GSC) are found to play a crucial role by increasing cancer aggressiveness and promoting resistance to therapy. Recently, crosstalk between GSC and vascular endothelial cells has been shown to significantly promote GSC self-renewal and tumor progression. Further, GSC also transdifferentiate into bona-fide vascular endothelial cells (GEC), which inherit mutations present in GSC and are resistant to traditional anti-angiogenic therapies. Here we use 3D mathematical modeling to investigate GBM progression and response to therapy. The model predicted that GSC drive invasive fingering and that GEC spontaneously form a network within the hypoxic core, consistent with published experimental findings. Standard-of-care treatments using DNA-targeted therapy (radiation/chemo) together with anti-angiogenic therapies, reduced GBM tumor size but increased invasiveness. Anti-GEC treatments blocked the GEC support of GSC and reduced tumor size but led to increased invasiveness. Anti-GSC therapies that promote differentiation or disturb the stem cell niche effectively reduced tumor invasiveness and size, but were ultimately limited in reducing tumor size because GEC maintain GSC. Our study suggests that a combinatorial regimen targeting the vasculature, GSC, and GEC, using drugs already approved by the FDA, can reduce both tumor size and invasiveness and could lead to tumor eradication. PMID:28536277

  2. Modeling global scene factors in attention

    Science.gov (United States)

    Torralba, Antonio

    2003-07-01

    Models of visual attention have focused predominantly on bottom-up approaches that ignored structured contextual and scene information. I propose a model of contextual cueing for attention guidance based on the global scene configuration. It is shown that the statistics of low-level features across the whole image can be used to prime the presence or absence of objects in the scene and to predict their location, scale, and appearance before exploring the image. In this scheme, visual context information can become available early in the visual processing chain, which allows modulation of the saliency of image regions and provides an efficient shortcut for object detection and recognition. 2003 Optical Society of America

  3. Model estimates of leaf area and reference canopy stomatal conductance suggest correlation between phenology and physiology in both trembling aspen and red pine

    Science.gov (United States)

    Mackay, D. S.; Ewers, B. E.; Kruger, E. L.

    2006-12-01

    Phenological variations impact water and carbon fluxes, as evidenced by the large interannual variability of net ecosystem exchange of carbon dioxide and evapotranspiration (ET). In northern Wisconsin we observed daily variations of canopy transpiration from hardwoods from 1.0 to 1.7 mm/day during the leaf unfolding period and 1.7 to 2.6 mm/day with leaves fully out. Correlations between such flux rates and phenology have not been extensively tested and mechanistic connections are in their infancy. Some data suggest that stomatal conductance and photosynthesis increases up to full expansion. Moreover, in conifers, the interaction of phenology and physiology is more complicated than in deciduous trees because needles are retained for several years. Using inverse modeling with a coupled photosynthesis-transpiration model we estimated reference canopy stomatal conductance, Gsref, for red pine (Pinus resinosa), and Gsref and leaf area index, L, for trembling aspen (Populus tremuloides), using 30-min continuous sap flux data spanning a period from just prior to the start of leaf expansion to just after leaf senescence. The red pine showed Gsref ramp up from 105 to 179 mmol m-2 leaf s-1, which represented a 37 to 50 percent increase in Gsref after accounting for maximum possible changes in L. After full leaf out, the trembling aspen were almost immediately defoliated, and then reflushed after three weeks. Model estimates of L reflected this pattern and were consistent with measurements. However, Gsref never exceeded 45 mmol m-2 s-1 prior to defoliation, but peaked at 112 mmol m-2 s-1 after reflushing. These results support the need for further work that aims to separate phenology and physiology.

  4. Testing for time-varying loadings in dynamic factor models

    DEFF Research Database (Denmark)

    Mikkelsen, Jakob Guldbæk

    Abstract: In this paper we develop a test for time-varying factor loadings in factor models. The test is simple to compute and is constructed from estimated factors and residuals using the principal components estimator. The hypothesis is tested by regressing the squared residuals on the squared...... there is evidence of time-varying loadings on the risk factors underlying portfolio returns for around 80% of the portfolios....

  5. Defense of single-factor models of population regulation

    International Nuclear Information System (INIS)

    Tamarin, R.H.

    1978-01-01

    I reject a multifactorial approach to the study of the regulation of animal populations for two reasons. First, a mechanism suggested by Chitty, that has natural selection at its base, has not been adequately tested. Second, the multifactorial model suggested by Lidicker is untestable because of its vagueness. As a middle ground, I suggest a model that has natural selection as its mechanism, but is multifacturial because it allows many parameters to be the selective agents. I particularly emphasize prediction and selective dispersal. Methods to test this model are suggested

  6. [Lake eutrophication modeling in considering climatic factors change: a review].

    Science.gov (United States)

    Su, Jie-Qiong; Wang, Xuan; Yang, Zhi-Feng

    2012-11-01

    Climatic factors are considered as the key factors affecting the trophic status and its process in most lakes. Under the background of global climate change, to incorporate the variations of climatic factors into lake eutrophication models could provide solid technical support for the analysis of the trophic evolution trend of lake and the decision-making of lake environment management. This paper analyzed the effects of climatic factors such as air temperature, precipitation, sunlight, and atmosphere on lake eutrophication, and summarized the research results about the lake eutrophication modeling in considering in considering climatic factors change, including the modeling based on statistical analysis, ecological dynamic analysis, system analysis, and intelligent algorithm. The prospective approaches to improve the accuracy of lake eutrophication modeling with the consideration of climatic factors change were put forward, including 1) to strengthen the analysis of the mechanisms related to the effects of climatic factors change on lake trophic status, 2) to identify the appropriate simulation models to generate several scenarios under proper temporal and spatial scales and resolutions, and 3) to integrate the climatic factors change simulation, hydrodynamic model, ecological simulation, and intelligent algorithm into a general modeling system to achieve an accurate prediction of lake eutrophication under climatic change.

  7. Physiologically based pharmacokinetic modeling of human exposure to perfluorooctanoic acid suggests historical non drinking-water exposures are important for predicting current serum concentrations.

    Science.gov (United States)

    Worley, Rachel Rogers; Yang, Xiaoxia; Fisher, Jeffrey

    2017-09-01

    Manufacturing of perfluorooctanoic acid (PFOA), a synthetic chemical with a long half-life in humans, peaked between 1970 and 2002, and has since diminished. In the United States, PFOA is detected in the blood of >99% of people tested, but serum concentrations have decreased since 1999. Much is known about exposure to PFOA in drinking water; however, the impact of non-drinking water PFOA exposure on serum PFOA concentrations is not well characterized. The objective of this research is to apply physiologically based pharmacokinetic (PBPK) modeling and Monte Carlo analysis to evaluate the impact of historic non-drinking water PFOA exposure on serum PFOA concentrations. In vitro to in vivo extrapolation was utilized to inform descriptions of PFOA transport in the kidney. Monte Carlo simulations were incorporated to evaluate factors that account for the large inter-individual variability of serum PFOA concentrations measured in individuals from North Alabama in 2010 and 2016, and the Mid-Ohio River Valley between 2005 and 2008. Predicted serum PFOA concentrations were within two-fold of experimental data. With incorporation of Monte Carlo simulations, the model successfully tracked the large variability of serum PFOA concentrations measured in populations from the Mid-Ohio River Valley. Simulation of exposure in a population of 45 adults from North Alabama successfully predicted 98% of individual serum PFOA concentrations measured in 2010 and 2016, respectively, when non-drinking water ingestion of PFOA exposure was included. Variation in serum PFOA concentrations may be due to inter-individual variability in the disposition of PFOA and potentially elevated historical non-drinking water exposures. Published by Elsevier Inc.

  8. The Research on Influencing Factors of Medical Logistics Cost Based on ISM Model

    Directory of Open Access Journals (Sweden)

    Zhai Yunkai

    2017-01-01

    Full Text Available The reason why medical logistics cost remains high is a system problem, this paper analyzes the system through the ISM model. The result presents that medical logistics cost factors have four levels of relationship, primary factor is the national policies, secondary factors are the talent construction and pharmaceutical enterprise scale, Intermediate factors are medical information management system and inventory cost, the key factors are transportation cost and distribution center location. Finally, according to the four levels of relationship, this paper put forward specific suggestions to reduce logistics cost.

  9. The determinant factors of open business model

    Directory of Open Access Journals (Sweden)

    Juan Mejía-Trejo

    2017-01-01

    Full Text Available Intro ducción : Desde principios del siglo XXI, varios autores afirman que los modelos de negocio abiertos (OBM permiten a una organización ser más eficaz en la creación y la ca p tura de valor siendo un requisito previo para el éxito de las asociaciones de co - des arrollo. Como resultado de las tendencias de: crecientes costos de desarrollo y ciclos de vida de los produ c tos/servicios más cortos, las empresas encuentran cada vez más difícil justificar las inversi o nes en innovación. El OBM resuelve ambas tendencias, s ubrayando los términos: " ecosistema de la industria " y/o " modelo de negocio colaborativo ". No sólo cambia el pr o ceso de innovación, sino que también modifica a las propias organizaciones mediante la r e configuración de sus cadenas de valor y redes. Para las empresas, crea una lógica heurística basada en el actual modelo de negocio y tecnología para extenderlas, con estrategia, al desa r rollo de la innov a ción para crear valor y aumentar los ingresos y beneficios. Enfatiza tanto las relaciones exte r nas así como la gobernabilidad, como valiosos recursos con varios roles que promueven la competitividad corporativa. Por lo tanto, para un sector especializado de alta tecnología como lo es el de las tecnologías de la información de la zona metropolitana de Guadalajar a (IT S MZG, exponemos el siguiente problema de investigación: ¿Cuáles son los factores determinantes de la OBM como modelo empírico que se aplc a do en el ITSMZG? Método: Como se ve, esta investigación tiene como objetivo plantear, los factores determ i nantes de la OBM como un modelo empírico que sea aplicado en el ITSMZG.Se trata de un estudio documental para seleccionar las principales v a riables entre los especialistas de las ITSMZG que practican el proceso OBM mediante el proceso de j e rarquía analítica (AHP y el Panel de Delphi a fin de contrastar los términos académicos con la experiencia de los e s pecialistas. Es un

  10. Latent factor modeling of four schizotypy dimensions with theory of mind and empathy.

    Directory of Open Access Journals (Sweden)

    Jeffrey S Bedwell

    Full Text Available Preliminary evidence suggests that theory of mind and empathy relate differentially to factors of schizotypy. The current study assessed 686 undergraduate students and used structural equation modeling to examine links between a four-factor model of schizotypy with performance on measures of theory of mind (Reading the Mind in the Eyes Test [MIE] and empathy (Interpersonal Reactivity Index [IRI]. Schizotypy was assessed using three self-report measures which were simultaneously entered into the model. Results revealed that the Negative factor of schizotypy showed a negative relationship with the Empathy factor, which was primarily driven by the Empathic Concern subscale of the IRI and the No Close Friends and Constricted Affect subscales of the Schizotypal Personality Questionnaire. These findings are consistent with a growing body of literature suggesting a relatively specific relationship between negative schizotypy and empathy, and are consistent with several previous studies that found no relationship between MIE performance and schizotypy.

  11. An alternative method for centrifugal compressor loading factor modelling

    Science.gov (United States)

    Galerkin, Y.; Drozdov, A.; Rekstin, A.; Soldatova, K.

    2017-08-01

    The loading factor at design point is calculated by one or other empirical formula in classical design methods. Performance modelling as a whole is out of consideration. Test data of compressor stages demonstrates that loading factor versus flow coefficient at the impeller exit has a linear character independent of compressibility. Known Universal Modelling Method exploits this fact. Two points define the function - loading factor at design point and at zero flow rate. The proper formulae include empirical coefficients. A good modelling result is possible if the choice of coefficients is based on experience and close analogs. Earlier Y. Galerkin and K. Soldatova had proposed to define loading factor performance by the angle of its inclination to the ordinate axis and by the loading factor at zero flow rate. Simple and definite equations with four geometry parameters were proposed for loading factor performance calculated for inviscid flow. The authors of this publication have studied the test performance of thirteen stages of different types. The equations are proposed with universal empirical coefficients. The calculation error lies in the range of plus to minus 1,5%. The alternative model of a loading factor performance modelling is included in new versions of the Universal Modelling Method.

  12. Model of key success factors for Business Intelligence implementation

    Directory of Open Access Journals (Sweden)

    Peter Mesaros

    2016-07-01

    Full Text Available New progressive technologies recorded growth in every area. Information-communication technologies facilitate the exchange of information and it facilitates management of everyday activities in enterprises. Specific modules (such as Business Intelligence facilitate decision-making. Several studies have demonstrated the positive impact of Business Intelligence to decision-making. The first step is to put in place the enterprise. The implementation process is influenced by many factors. This article discusses the issue of key success factors affecting to successful implementation of Business Intelligence. The article describes the key success factors for successful implementation and use of Business Intelligence based on multiple studies. The main objective of this study is to verify the effects and dependence of selected factors and proposes a model of key success factors for successful implementation of Business Intelligence. Key success factors and the proposed model are studied in Slovak enterprises.

  13. Effects of anti-inflammatory compounds on sulfur mustard injured cells: Recommendations and caveats suggested by in vitro cell culture models.

    Science.gov (United States)

    Menacher, Georg; Steinritz, Dirk; Schmidt, Annette; Popp, Tanja; Worek, Franz; Gudermann, Thomas; Thiermann, Horst; Balszuweit, Frank

    2018-09-01

    Sulfur mustard (SM) is a vesicant agent who had its first military use 100 years ago, in Ypres. Since then it has been used in several conflicts like the Iran-Iraq war in the 1980s. The use of SM in Syria 2015 indicated the still existing threat. Despite decades of research no causal antidote against SM intoxication is available, so far. A SM intoxication is accompanied by necrosis, apoptosis and inflammation. To counteract the SM-induced inflammation, glucocorticoids and non-steroidal anti-inflammatory compounds (NSAIDs) are recommended. Aim of this study was to evaluate the efficacy of the anti-inflammatory compounds dexamethasone, ibuprofen and diclofenac in vitro. For that purpose, two different cell culture models were used. Firstly, a monoculture of keratinocytes (HaCaT) and secondly, an established co-culture of keratinocytes (HaCaT) and immunocompetent cells (THP-1) to identify the role of immune cells in the process and to mimic the dermal physiology more closely. Both models were challenged with different SM concentrations (100, 200 and 300μM) and treated with different anti-inflammatory compounds one hour after the SM exposure. Analytical analysis of necrosis (ToxiLight), apoptosis (CDDE) and inflammation (IL-6 and -8 ELISAs) followed 24h thereafter. Dexamethasone provided small but consistent protective effects in the monoculture. For the reduction of apoptosis, 3μM dexamethasone was sufficient. The most effective reduction regarding interleukin (IL) production was found with 6μM dexamethasone. Protective effects were less pronounced in co-culture, which implies, that the protective effects of dexamethasone are rather generic and not due to a modulation of the immune cells. Against our expectations, ibuprofen strongly amplified apoptosis and necrosis in SM exposed cells in the monoculture as well as the co-culture. Therefore, use of ibuprofen for treatment of SM intoxication should at least be considered most critically, if not even regarded as

  14. Functional dynamic factor models with application to yield curve forecasting

    KAUST Repository

    Hays, Spencer; Shen, Haipeng; Huang, Jianhua Z.

    2012-01-01

    resulted in a trade-off between goodness of fit and consistency with economic theory. To address this, herein we propose a novel formulation which connects the dynamic factor model (DFM) framework with concepts from functional data analysis: a DFM

  15. Human Modeling for Ground Processing Human Factors Engineering Analysis

    Science.gov (United States)

    Stambolian, Damon B.; Lawrence, Brad A.; Stelges, Katrine S.; Steady, Marie-Jeanne O.; Ridgwell, Lora C.; Mills, Robert E.; Henderson, Gena; Tran, Donald; Barth, Tim

    2011-01-01

    There have been many advancements and accomplishments over the last few years using human modeling for human factors engineering analysis for design of spacecraft. The key methods used for this are motion capture and computer generated human models. The focus of this paper is to explain the human modeling currently used at Kennedy Space Center (KSC), and to explain the future plans for human modeling for future spacecraft designs

  16. Dependent defaults and losses with factor copula models

    Directory of Open Access Journals (Sweden)

    Ackerer Damien

    2017-12-01

    Full Text Available We present a class of flexible and tractable static factor models for the term structure of joint default probabilities, the factor copula models. These high-dimensional models remain parsimonious with paircopula constructions, and nest many standard models as special cases. The loss distribution of a portfolio of contingent claims can be exactly and efficiently computed when individual losses are discretely supported on a finite grid. Numerical examples study the key features affecting the loss distribution and multi-name credit derivatives prices. An empirical exercise illustrates the flexibility of our approach by fitting credit index tranche prices.

  17. Quantifying credit portfolio losses under multi-factor models

    NARCIS (Netherlands)

    G. Colldeforns-Papiol (Gemma); L. Ortiz Gracia (Luis); C.W. Oosterlee (Kees)

    2018-01-01

    textabstractIn this work, we investigate the challenging problem of estimating credit risk measures of portfolios with exposure concentration under the multi-factor Gaussian and multi-factor t-copula models. It is well-known that Monte Carlo (MC) methods are highly demanding from the computational

  18. Rethinking "Harmonious Parenting" Using a Three-Factor Discipline Model

    Science.gov (United States)

    Greenspan, Stephen

    2006-01-01

    Diana Baumrind's typology of parenting is based on a two-factor model of "control" and "warmth". Her recommended discipline style, labeled "authoritative parenting", was constructed by taking high scores on these two factors. A problem with authoritative parenting is that it does not allow for flexible and differentiated responses to discipline…

  19. Person-fit to the Five Factor Model of personality

    Czech Academy of Sciences Publication Activity Database

    Allik, J.; Realo, A.; Mõttus, R.; Borkenau, P.; Kuppens, P.; Hřebíčková, Martina

    2012-01-01

    Roč. 71, č. 1 (2012), s. 35-45 ISSN 1421-0185 R&D Projects: GA ČR GAP407/10/2394 Institutional research plan: CEZ:AV0Z70250504 Keywords : Five Factor Model * cross - cultural comparison * person-fit Subject RIV: AN - Psychology Impact factor: 0.638, year: 2012

  20. Is There Really a Global Business Cycle? : A Dynamic Factor Model with Stochastic Factor Selection

    NARCIS (Netherlands)

    T. Berger (Tino); L.C.G. Pozzi (Lorenzo)

    2016-01-01

    textabstractWe investigate the presence of international business cycles in macroeconomic aggregates (output, consumption, investment) using a panel of 60 countries over the period 1961-2014. The paper presents a Bayesian stochastic factor selection approach for dynamic factor models with

  1. Interrogative suggestibility in opiate users.

    Science.gov (United States)

    Murakami, A; Edelmann, R J; Davis, P E

    1996-09-01

    The present study investigated interrogative suggestibility in opiate users. A group of patients undergoing a methadone detoxification programme in an in-patient drug treatment unit (Detox group, n = 21), and a group of residents who had come off drugs and were no longer suffering from withdrawal syndrome (Rehab group, n = 19) were compared on interrogative suggestibility and various other psychological factors. Significant differences were found between the two groups, with the Detox group having more physical and psychological problems, and a higher total suggestibility score in comparison with the Rehab group. These findings are discussed in relation to the context of police interrogations and the reliability of confessions made by suspects and witnesses dependent on opiates.

  2. Innovative supply chain optimization models with multiple uncertainty factors

    DEFF Research Database (Denmark)

    Choi, Tsan Ming; Govindan, Kannan; Li, Xiang

    2017-01-01

    Uncertainty is an inherent factor that affects all dimensions of supply chain activities. In today’s business environment, initiatives to deal with one specific type of uncertainty might not be effective since other types of uncertainty factors and disruptions may be present. These factors relate...... to supply chain competition and coordination. Thus, to achieve a more efficient and effective supply chain requires the deployment of innovative optimization models and novel methods. This preface provides a concise review of critical research issues regarding innovative supply chain optimization models...

  3. A temperature dependent slip factor based thermal model for friction

    Indian Academy of Sciences (India)

    This paper proposes a new slip factor based three-dimensional thermal model to predict the temperature distribution during friction stir welding of 304L stainless steel plates. The proposed model employs temperature and radius dependent heat source to study the thermal cycle, temperature distribution, power required, the ...

  4. Study on visibility evaluation model which is considered field factors; Field factor wo koryoshita shininsei hyoka model ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Nakanishi, M; Hagiwara, T [Hokkaido University, Sapporo (Japan)

    1997-10-01

    The present study proposes a model to evaluate visual performance of road traffic facilities required for drivers. Two factors were employed to obtain the suitable contrast for drivers under driving situation. One factor is a suitable luminance range, which is derived from minimum required luminance and glare luminance. Another is a field. The model showed capability of providing visibility range in some cases. 8 refs., 4 figs., 2 tabs.

  5. Capital Cost Optimization for Prefabrication: A Factor Analysis Evaluation Model

    Directory of Open Access Journals (Sweden)

    Hong Xue

    2018-01-01

    Full Text Available High capital cost is a significant hindrance to the promotion of prefabrication. In order to optimize cost management and reduce capital cost, this study aims to explore the latent factors and factor analysis evaluation model. Semi-structured interviews were conducted to explore potential variables and then questionnaire survey was employed to collect professionals’ views on their effects. After data collection, exploratory factor analysis was adopted to explore the latent factors. Seven latent factors were identified, including “Management Index”, “Construction Dissipation Index”, “Productivity Index”, “Design Efficiency Index”, “Transport Dissipation Index”, “Material increment Index” and “Depreciation amortization Index”. With these latent factors, a factor analysis evaluation model (FAEM, divided into factor analysis model (FAM and comprehensive evaluation model (CEM, was established. The FAM was used to explore the effect of observed variables on the high capital cost of prefabrication, while the CEM was used to evaluate comprehensive cost management level on prefabrication projects. Case studies were conducted to verify the models. The results revealed that collaborative management had a positive effect on capital cost of prefabrication. Material increment costs and labor costs had significant impacts on production cost. This study demonstrated the potential of on-site management and standardization design to reduce capital cost. Hence, collaborative management is necessary for cost management of prefabrication. Innovation and detailed design were needed to improve cost performance. The new form of precast component factories can be explored to reduce transportation cost. Meanwhile, targeted strategies can be adopted for different prefabrication projects. The findings optimized the capital cost and improved the cost performance through providing an evaluation and optimization model, which helps managers to

  6. Factor copula models for data with spatio-temporal dependence

    KAUST Repository

    Krupskii, Pavel

    2017-10-13

    We propose a new copula model for spatial data that are observed repeatedly in time. The model is based on the assumption that there exists a common factor that affects the measurements of a process in space and in time. Unlike models based on multivariate normality, our model can handle data with tail dependence and asymmetry. The likelihood for the proposed model can be obtained in a simple form and therefore parameter estimation is quite fast. Simulation from this model is straightforward and data can be predicted at any spatial location and time point. We use simulation studies to show different types of dependencies, both in space and in time, that can be generated by this model. We apply the proposed copula model to hourly wind data and compare its performance with some classical models for spatio-temporal data.

  7. Factor copula models for data with spatio-temporal dependence

    KAUST Repository

    Krupskii, Pavel; Genton, Marc G.

    2017-01-01

    We propose a new copula model for spatial data that are observed repeatedly in time. The model is based on the assumption that there exists a common factor that affects the measurements of a process in space and in time. Unlike models based on multivariate normality, our model can handle data with tail dependence and asymmetry. The likelihood for the proposed model can be obtained in a simple form and therefore parameter estimation is quite fast. Simulation from this model is straightforward and data can be predicted at any spatial location and time point. We use simulation studies to show different types of dependencies, both in space and in time, that can be generated by this model. We apply the proposed copula model to hourly wind data and compare its performance with some classical models for spatio-temporal data.

  8. Factors Affecting Career Decision-Making: Further Validation of the O'Neil Career-Sex Role Model and the Career Factor Checklist.

    Science.gov (United States)

    Meinecke, Christine; O'Neil, James M.

    Many correlates of vocational choice have been suggested by career development theorists. A career decision-making model developed by O'Neil, Meeker, and Borgers suggests six factors (individual, societal, familial, socioeconomic, situational, psychosocial-emotional) that affect both sex role socialization and career decision-making. The validity…

  9. Lowest Astronomical Tide in the North Sea derived from a vertically referenced shallow water model, and an assessment of its suggested sense of safety

    NARCIS (Netherlands)

    Slobbe, D.C.; Klees, R.; Verlaan, M.; Dorst, L.; Gerritsen, H.

    2012-01-01

    In this study, LAT will be modeled relative to a geoid, after which the ellipsoidal heights of LAT will be obtained by adding geoid heights to the modeled LAT values. The use of a geoid instead of MSL has the advantage that the former can be realized everywhere and does not leave a gap along the

  10. Evaluation of the Thermodynamic Models for the Thermal Diffusion Factor

    DEFF Research Database (Denmark)

    Gonzalez-Bagnoli, Mariana G.; Shapiro, Alexander; Stenby, Erling Halfdan

    2003-01-01

    Over the years, several thermodynamic models for the thermal diffusion factors for binary mixtures have been proposed. The goal of this paper is to test some of these models in combination with different equations of state. We tested the following models: those proposed by Rutherford and Drickamer...... we applied different thermodynamic models, such as the Soave-Redlich-Kwong and the Peng-Robinson equations of state. The necessity to try different thermo-dynamic models is caused by the high sensitivity of the thermal diffusion factors to the values of the partial molar properties. Two different...... corrections for the determination of the partial molar volumes have been implemented; the Peneloux correction and the correction based on the principle of corresponding states....

  11. Uncovering Transcriptional Regulatory Networks by Sparse Bayesian Factor Model

    Directory of Open Access Journals (Sweden)

    Qi Yuan(Alan

    2010-01-01

    Full Text Available Abstract The problem of uncovering transcriptional regulation by transcription factors (TFs based on microarray data is considered. A novel Bayesian sparse correlated rectified factor model (BSCRFM is proposed that models the unknown TF protein level activity, the correlated regulations between TFs, and the sparse nature of TF-regulated genes. The model admits prior knowledge from existing database regarding TF-regulated target genes based on a sparse prior and through a developed Gibbs sampling algorithm, a context-specific transcriptional regulatory network specific to the experimental condition of the microarray data can be obtained. The proposed model and the Gibbs sampling algorithm were evaluated on the simulated systems, and results demonstrated the validity and effectiveness of the proposed approach. The proposed model was then applied to the breast cancer microarray data of patients with Estrogen Receptor positive ( status and Estrogen Receptor negative ( status, respectively.

  12. The multi-factor energy input–output model

    International Nuclear Information System (INIS)

    Guevara, Zeus; Domingos, Tiago

    2017-01-01

    Energy input–output analysis (EIO analysis) is a noteworthy tool for the analysis of the role of energy in the economy. However, it has relied on models that provide a limited description of energy flows in the economic system and do not allow an adequate analysis of energy efficiency. This paper introduces a novel energy input–output model, the multi-factor energy input–output model (MF-EIO model), which is obtained from a partitioning of a hybrid-unit input–output system of the economy. This model improves on current models by describing the energy flows according to the processes of energy conversion and the levels of energy use in the economy. It characterizes the vector of total energy output as a function of seven factors: two energy efficiency indicators; two characteristics of end-use energy consumption; and three economic features of the rest of the economy. Moreover, it is consistent with the standard model for EIO analysis, i.e., the hybrid-unit model. This paper also introduces an approximate version of the MF-EIO model, which is equivalent to the former under equal energy prices for industries and final consumers, but requires less data processing. The latter is composed by two linked models: a model of the energy sector in physical units, and a model of the rest of the economy in monetary units. In conclusion, the proposed modelling framework improves EIO analysis and extends EIO applications to the accounting for energy efficiency of the economy. - Highlights: • A novel energy input–output model is introduced. • It allows a more adequate analysis of energy flows than current models. • It describes energy flows according to processes of energy conversion and use. • It can be used for other environmental applications (material use and emissions). • An approximate version of the model is introduced, simpler and less data intensive.

  13. Supplementary Material for: Factor Copula Models for Replicated Spatial Data

    KAUST Repository

    Krupskii, Pavel; Huser, Raphaë l; Genton, Marc G.

    2016-01-01

    We propose a new copula model that can be used with replicated spatial data. Unlike the multivariate normal copula, the proposed copula is based on the assumption that a common factor exists and affects the joint dependence of all measurements of the process. Moreover, the proposed copula can model tail dependence and tail asymmetry. The model is parameterized in terms of a covariance function that may be chosen from the many models proposed in the literature, such as the Matérn model. For some choice of common factors, the joint copula density is given in closed form and therefore likelihood estimation is very fast. In the general case, one-dimensional numerical integration is needed to calculate the likelihood, but estimation is still reasonably fast even with large data sets. We use simulation studies to show the wide range of dependence structures that can be generated by the proposed model with different choices of common factors. We apply the proposed model to spatial temperature data and compare its performance with some popular geostatistics models.

  14. Model calculation of the scanned field enhancement factor of CNTs

    International Nuclear Information System (INIS)

    Ahmad, Amir; Tripathi, V K

    2006-01-01

    The field enhancement factor of a carbon nanotube (CNT) placed in a cluster of CNTs is smaller than an isolated CNT because the electric field on one tube is screened by neighbouring tubes. This screening depends on the length of the CNTs and the spacing between them. We have derived an expression to compute the field enhancement factor of CNTs under any positional distribution of CNTs using a model of a floating sphere between parallel anode and cathode plates. Using this expression we can compute the field enhancement factor of a CNT in a cluster (non-uniformly distributed CNTs). This expression is used to compute the field enhancement factor of a CNT in an array (uniformly distributed CNTs). Comparison has been shown with experimental results and existing models

  15. HIGH DIMENSIONAL COVARIANCE MATRIX ESTIMATION IN APPROXIMATE FACTOR MODELS.

    Science.gov (United States)

    Fan, Jianqing; Liao, Yuan; Mincheva, Martina

    2011-01-01

    The variance covariance matrix plays a central role in the inferential theories of high dimensional factor models in finance and economics. Popular regularization methods of directly exploiting sparsity are not directly applicable to many financial problems. Classical methods of estimating the covariance matrices are based on the strict factor models, assuming independent idiosyncratic components. This assumption, however, is restrictive in practical applications. By assuming sparse error covariance matrix, we allow the presence of the cross-sectional correlation even after taking out common factors, and it enables us to combine the merits of both methods. We estimate the sparse covariance using the adaptive thresholding technique as in Cai and Liu (2011), taking into account the fact that direct observations of the idiosyncratic components are unavailable. The impact of high dimensionality on the covariance matrix estimation based on the factor structure is then studied.

  16. The five-factor model in schizotypal personality disorder

    OpenAIRE

    Gurrera, Ronald J.; Dickey, Chandlee C.; Niznikiewicz, Margaret A.; Voglmaier, Martina M.; Shenton, Martha E.; McCarley, Robert W.

    2005-01-01

    Studies of the five-factor model of personality in schizotypal personality disorder (SPD) have produced inconsistent results, particularly with respect to openness. In the present study, the NEO-FFI was used to measure five-factor personality dimensions in 28 community volunteers with SPD and 24 psychiatrically healthy individuals. Standard multivariate statistical analyses were used to evaluate personality differences as a function of diagnosis and gender. Individuals with SPD had significan...

  17. DISTANCE AS KEY FACTOR IN MODELLING STUDENTS’ RECRUITMENT BY UNIVERSITIES

    Directory of Open Access Journals (Sweden)

    SIMONA MĂLĂESCU

    2015-10-01

    Full Text Available Distance as Key Factor in Modelling Students’ Recruitment by Universities. In a previous paper analysing the challenge of keeping up with the current methodologies in the analysis and modelling of students’ recruitment by universities in the case of some ECE countries which still don’t register or develop key data to take advantage from the state of the art knowledge on the domain, we have promised to approach the factor distance in a future work due to the extent of the topic. This paper fulfill that promise bringing a review of the literature especially dealing with modelling the geographical area of recruiting students of an university, where combining distance with the proximate key factors previously reviewed, complete the meta-analysis of existing literature we have started a year ago. Beyond the theoretical benefit from a practical perspective, the metaanalysis aimed at synthesizing elements of good practice that can be applied to the local university system.

  18. Consumer's Online Shopping Influence Factors and Decision-Making Model

    Science.gov (United States)

    Yan, Xiangbin; Dai, Shiliang

    Previous research on online consumer behavior has mostly been confined to the perceived risk which is used to explain those barriers for purchasing online. However, perceived benefit is another important factor which influences consumers’ decision when shopping online. As a result, an integrated consumer online shopping decision-making model is developed which contains three elements—Consumer, Product, and Web Site. This model proposed relative factors which influence the consumers’ intention during the online shopping progress, and divided them into two different dimensions—mentally level and material level. We tested those factors with surveys, from both online volunteers and offline paper surveys with more than 200 samples. With the help of SEM, the experimental results show that the proposed model and method can be used to analyze consumer’s online shopping decision-making process effectively.

  19. Molecular modelling of the Norrie disease protein predicts a cystine knot growth factor tertiary structure.

    Science.gov (United States)

    Meitinger, T; Meindl, A; Bork, P; Rost, B; Sander, C; Haasemann, M; Murken, J

    1993-12-01

    The X-lined gene for Norrie disease, which is characterized by blindness, deafness and mental retardation has been cloned recently. This gene has been thought to code for a putative extracellular factor; its predicted amino acid sequence is homologous to the C-terminal domain of diverse extracellular proteins. Sequence pattern searches and three-dimensional modelling now suggest that the Norrie disease protein (NDP) has a tertiary structure similar to that of transforming growth factor beta (TGF beta). Our model identifies NDP as a member of an emerging family of growth factors containing a cystine knot motif, with direct implications for the physiological role of NDP. The model also sheds light on sequence related domains such as the C-terminal domain of mucins and of von Willebrand factor.

  20. Reply to comment on 'Model calculation of the scanned field enhancement factor of CNTs'

    International Nuclear Information System (INIS)

    Ahmad, Amir; Tripathi, V K

    2010-01-01

    In the paper (Ahmad and Tripathi 2006 Nanotechnology 17 3798), we derived an expression to compute the field enhancement factor of CNTs under any positional distribution of CNTs by using the model of a floating sphere between parallel anode and cathode plates. Using this expression we can compute the field enhancement factor of a CNT in a cluster (non-uniformly distributed CNTs). This expression was used to compute the field enhancement factor of a CNT in an array (uniformly distributed CNTs). We used an approximation to calculate the field enhancement factor. Hence, our expressions are correct in that assumption only. Zhbanov et al (2010 Nanotechnology 21 358001) suggest a correction that can calculate the field enhancement factor without using the approximation. Hence, this correction can improve the applicability of this model. (reply)

  1. Orchestrated Regulation of Nogo Receptors, Lotus, AMPA Receptors and BDNF in an ECT Model Suggests Opening and Closure of a Window of Synaptic Plasticity

    OpenAIRE

    Nordgren, Max; Karlsson, Tobias; Svensson, Maria; Koczy, Josefin; Josephson, Anna; Olson, Lars; Tingstroem, Anders; Brene, Stefan

    2013-01-01

    Electroconvulsive therapy (ECT) is an efficient and relatively fast acting treatment for depression. However, one severe side effect of the treatment is retrograde amnesia, which in certain cases can be long-term. The mechanisms behind the antidepressant effect and the amnesia are not well understood. We hypothesized that ECT causes transient downregulation of key molecules needed to stabilize synaptic structure and to prevent Ca2+ influx, and a simultaneous increase in neurotrophic factors, ...

  2. A rough multi-factor model of electricity spot prices

    International Nuclear Information System (INIS)

    Bennedsen, Mikkel

    2017-01-01

    We introduce a new continuous-time mathematical model of electricity spot prices which accounts for the most important stylized facts of these time series: seasonality, spikes, stochastic volatility, and mean reversion. Empirical studies have found a possible fifth stylized fact, roughness, and our approach explicitly incorporates this into the model of the prices. Our setup generalizes the popular Ornstein–Uhlenbeck-based multi-factor framework of and allows us to perform statistical tests to distinguish between an Ornstein–Uhlenbeck-based model and a rough model. Further, through the multi-factor approach we account for seasonality and spikes before estimating – and making inference on – the degree of roughness. This is novel in the literature and we present simulation evidence showing that these precautions are crucial for accurate estimation. Lastly, we estimate our model on recent data from six European energy exchanges and find statistical evidence of roughness in five out of six markets. As an application of our model, we show how, in these five markets, a rough component improves short term forecasting of the prices. - Highlights: • Statistical modeling of electricity spot prices • Multi-factor decomposition • Roughness • Electricity price forecasting

  3. Functional dynamic factor models with application to yield curve forecasting

    KAUST Repository

    Hays, Spencer

    2012-09-01

    Accurate forecasting of zero coupon bond yields for a continuum of maturities is paramount to bond portfolio management and derivative security pricing. Yet a universal model for yield curve forecasting has been elusive, and prior attempts often resulted in a trade-off between goodness of fit and consistency with economic theory. To address this, herein we propose a novel formulation which connects the dynamic factor model (DFM) framework with concepts from functional data analysis: a DFM with functional factor loading curves. This results in a model capable of forecasting functional time series. Further, in the yield curve context we show that the model retains economic interpretation. Model estimation is achieved through an expectation- maximization algorithm, where the time series parameters and factor loading curves are simultaneously estimated in a single step. Efficient computing is implemented and a data-driven smoothing parameter is nicely incorporated. We show that our model performs very well on forecasting actual yield data compared with existing approaches, especially in regard to profit-based assessment for an innovative trading exercise. We further illustrate the viability of our model to applications outside of yield forecasting.

  4. Container Throughput Forecasting Using Dynamic Factor Analysis and ARIMAX Model

    Directory of Open Access Journals (Sweden)

    Marko Intihar

    2017-11-01

    Full Text Available The paper examines the impact of integration of macroeconomic indicators on the accuracy of container throughput time series forecasting model. For this purpose, a Dynamic factor analysis and AutoRegressive Integrated Moving-Average model with eXogenous inputs (ARIMAX are used. Both methodologies are integrated into a novel four-stage heuristic procedure. Firstly, dynamic factors are extracted from external macroeconomic indicators influencing the observed throughput. Secondly, the family of ARIMAX models of different orders is generated based on the derived factors. In the third stage, the diagnostic and goodness-of-fit testing is applied, which includes statistical criteria such as fit performance, information criteria, and parsimony. Finally, the best model is heuristically selected and tested on the real data of the Port of Koper. The results show that by applying macroeconomic indicators into the forecasting model, more accurate future throughput forecasts can be achieved. The model is also used to produce future forecasts for the next four years indicating a more oscillatory behaviour in (2018-2020. Hence, care must be taken concerning any bigger investment decisions initiated from the management side. It is believed that the proposed model might be a useful reinforcement of the existing forecasting module in the observed port.

  5. Emotional intelligence is a second-stratum factor of intelligence: evidence from hierarchical and bifactor models.

    Science.gov (United States)

    MacCann, Carolyn; Joseph, Dana L; Newman, Daniel A; Roberts, Richard D

    2014-04-01

    This article examines the status of emotional intelligence (EI) within the structure of human cognitive abilities. To evaluate whether EI is a 2nd-stratum factor of intelligence, data were fit to a series of structural models involving 3 indicators each for fluid intelligence, crystallized intelligence, quantitative reasoning, visual processing, and broad retrieval ability, as well as 2 indicators each for emotion perception, emotion understanding, and emotion management. Unidimensional, multidimensional, hierarchical, and bifactor solutions were estimated in a sample of 688 college and community college students. Results suggest adequate fit for 2 models: (a) an oblique 8-factor model (with 5 traditional cognitive ability factors and 3 EI factors) and (b) a hierarchical solution (with cognitive g at the highest level and EI representing a 2nd-stratum factor that loads onto g at λ = .80). The acceptable relative fit of the hierarchical model confirms the notion that EI is a group factor of cognitive ability, marking the expression of intelligence in the emotion domain. The discussion proposes a possible expansion of Cattell-Horn-Carroll theory to include EI as a 2nd-stratum factor of similar standing to factors such as fluid intelligence and visual processing.

  6. Probabilistic Multi-Factor Interaction Model for Complex Material Behavior

    Science.gov (United States)

    Abumeri, Galib H.; Chamis, Christos C.

    2010-01-01

    Complex material behavior is represented by a single equation of product form to account for interaction among the various factors. The factors are selected by the physics of the problem and the environment that the model is to represent. For example, different factors will be required for each to represent temperature, moisture, erosion, corrosion, etc. It is important that the equation represent the physics of the behavior in its entirety accurately. The Multi-Factor Interaction Model (MFIM) is used to evaluate the divot weight (foam weight ejected) from the external launch tanks. The multi-factor has sufficient degrees of freedom to evaluate a large number of factors that may contribute to the divot ejection. It also accommodates all interactions by its product form. Each factor has an exponent that satisfies only two points - the initial and final points. The exponent describes a monotonic path from the initial condition to the final. The exponent values are selected so that the described path makes sense in the absence of experimental data. In the present investigation, the data used were obtained by testing simulated specimens in launching conditions. Results show that the MFIM is an effective method of describing the divot weight ejected under the conditions investigated. The problem lies in how to represent the divot weight with a single equation. A unique solution to this problem is a multi-factor equation of product form. Each factor is of the following form (1 xi/xf)ei, where xi is the initial value, usually at ambient conditions, xf the final value, and ei the exponent that makes the curve represented unimodal that meets the initial and final values. The exponents are either evaluated by test data or by technical judgment. A minor disadvantage may be the selection of exponents in the absence of any empirical data. This form has been used successfully in describing the foam ejected in simulated space environmental conditions. Seven factors were required

  7. Antecedents Factors that Influence Soy Consumption: A Structural Equation Modeling Approach

    OpenAIRE

    Balasubramanian, Siva K.; Moon, Wanki; Rimal, Arbindra; Coker, Kesha

    2009-01-01

    We propose a structural model of antecedent factors that affect the frequency of soy consumption. This model, suggests that soy-general knowledge influences perceptions about nutrition concern, health benefits of soy, soy related personal beliefs and personal attitudes toward soy. Health benefits of soy, in turn, impacts soy-related personal beliefs and personal attitudes toward soy. Additionally, soy-related personal beliefs influence personal attitudes toward soy. Finally, both nutrition co...

  8. Dynamic Multi-Factor Credit Risk Model with Fat-Tailed Factors

    Czech Academy of Sciences Publication Activity Database

    Gapko, Petr; Šmíd, Martin

    2012-01-01

    Roč. 62, č. 2 (2012), s. 125-140 ISSN 0015-1920 R&D Projects: GA ČR GD402/09/H045; GA ČR GA402/09/0965 Grant - others:Univerzita Karlova(CZ) GAUK 46108 Institutional research plan: CEZ:AV0Z10750506 Keywords : credit risk * probability of default * loss given default * credit loss * credit loss distribution * Basel II Subject RIV: AH - Economics Impact factor: 0.340, year: 2012 http://library.utia.cas.cz/separaty/2012/E/smid-dynamic multi-factor credit risk model with fat-tailed factors.pdf

  9. Consultation and illness behaviour in response to symptoms: A comparison of models from different disciplinary frameworks and suggestions for future research directions

    NARCIS (Netherlands)

    Wyke, S.; Adamson, J.; Dixon, D.; Hunt, K.

    2013-01-01

    We all get ill and social scientific interest in how we respond - the study of illness behaviour - continues unabated. Existing models are useful, but have been developed and applied within disciplinary silos, resulting in wasted intellectual and empirical effort and an absence of accumulation of

  10. Statistical Modeling Suggests that Antiandrogens in Effluents from Wastewater Treatment Works Contribute to Widespread Sexual Disruption in Fish Living in English Rivers

    Science.gov (United States)

    Jobling, Susan; Burn, Robert. W.; Thorpe, Karen; Williams, Richard; Tyler, Charles

    2009-01-01

    Background The widespread occurrence of feminized male fish downstream of some wastewater treatment works has led to substantial interest from ecologists and public health professionals. This concern stems from the view that the effects observed have a parallel in humans, and that both phenomena are caused by exposure to mixtures of contaminants that interfere with reproductive development. The evidence for a “wildlife–human connection” is, however, weak: Testicular dysgenesis syndrome, seen in human males, is most easily reproduced in rodent models by exposure to mixtures of antiandrogenic chemicals. In contrast, the accepted explanation for feminization of wild male fish is that it results mainly from exposure to steroidal estrogens originating primarily from human excretion. Objectives We sought to further explore the hypothesis that endocrine disruption in fish is multicausal, resulting from exposure to mixtures of chemicals with both estrogenic and antiandrogenic properties. Methods We used hierarchical generalized linear and generalized additive statistical modeling to explore the associations between modeled concentrations and activities of estrogenic and antiandrogenic chemicals in 30 U.K. rivers and feminized responses seen in wild fish living in these rivers. Results In addition to the estrogenic substances, antiandrogenic activity was prevalent in almost all treated sewage effluents tested. Further, the results of the modeling demonstrated that feminizing effects in wild fish could be best modeled as a function of their predicted exposure to both antiandrogens and estrogens or to antiandrogens alone. Conclusion The results provide a strong argument for a multicausal etiology of widespread feminization of wild fish in U.K. rivers involving contributions from both steroidal estrogens and xenoestrogens and from other (as yet unknown) contaminants with antiandrogenic properties. These results may add further credence to the hypothesis that endocrine

  11. Classification of hadith into positive suggestion, negative suggestion, and information

    Science.gov (United States)

    Faraby, Said Al; Riviera Rachmawati Jasin, Eliza; Kusumaningrum, Andina; Adiwijaya

    2018-03-01

    As one of the Muslim life guidelines, based on the meaning of its sentence(s), a hadith can be viewed as a suggestion for doing something, or a suggestion for not doing something, or just information without any suggestion. In this paper, we tried to classify the Bahasa translation of hadith into the three categories using machine learning approach. We tried stemming and stopword removal in preprocessing, and TF-IDF of unigram, bigram, and trigram as the extracted features. As the classifier, we compared between SVM and Neural Network. Since the categories are new, so in order to compare the results of the previous pipelines, we created a baseline classifier using simple rule-based string matching technique. The rule-based algorithm conditions on the occurrence of words such as “janganlah, sholatlah, and so on” to determine the category. The baseline method achieved F1-Score of 0.69, while the best F1-Score from the machine learning approach was 0.88, and it was produced by SVM model with the linear kernel.

  12. Modeling wind adjustment factor and midflame wind speed for Rothermel's surface fire spread model

    Science.gov (United States)

    Patricia L. Andrews

    2012-01-01

    Rothermel's surface fire spread model was developed to use a value for the wind speed that affects surface fire, called midflame wind speed. Models have been developed to adjust 20-ft wind speed to midflame wind speed for sheltered and unsheltered surface fuel. In this report, Wind Adjustment Factor (WAF) model equations are given, and the BehavePlus fire modeling...

  13. Endometriosis education in schools: A New Zealand model examining the impact of an education program in schools on early recognition of symptoms suggesting endometriosis.

    Science.gov (United States)

    Bush, Deborah; Brick, Emily; East, Michael C; Johnson, Neil

    2017-08-01

    Menstrual morbidity plays a significant role in adolescent females' lives. There are no studies to date reporting such data from menstrual health education programs in schools. The aim of our study was to report results from an audit of a menstrual health and endometriosis education program in secondary schools and observe age patterns of young women presenting for menstrual morbidity care. Audit data from education in secondary schools and audit data of patients from an Endometriosis and Pelvic Pain Coaching clinic operating in a private endometriosis specialised centre are reported. In a region of consistent delivery of the education program, student awareness of endometriosis was 32% in 2015. Overall in 2015, 13% of students experienced distressing menstrual symptoms and 27% of students sometimes or always missed school due to menstrual symptoms. Further, in one region of consistent delivery of the menstrual health education program, data show an increase in younger patients attending for specialised endometriosis care. There is strong suggestive evidence that consistent delivery of a menstrual health education program in schools increases adolescent student awareness of endometriosis. In addition, there is suggestive evidence that in a geographical area of consistent delivery of the program, a shift in earlier presentation of young women to a specialised health service is observed. © 2017 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  14. Rasch models suggested the satisfactory psychometric properties of the World Health Organization Quality of Life-Brief among lung cancer patients.

    Science.gov (United States)

    Lin, Chung-Ying; Yang, Szu-Chun; Lai, Wu-Wei; Su, Wu-Chou; Wang, Jung-Der

    2017-03-01

    The study examined whether the items of the World Health Organization Quality of Life-Brief questionnaire can assess its four underlying domains (Physical, Psychological, Social, and Environment) in a sample of lung cancer patients. All patients ( n = 1150) were recruited from a medical center in Tainan, and each participant completed the World Health Organization Quality of Life-Brief. Several Rasch rating scale models were used to examine the data-model fit, and Rasch analyses corroborated that each domain of the World Health Organization Quality of Life-Brief could be unidimensional. Although three items were found to have a poor fit, all the other items fit the unidimensionality with ordered thresholds.

  15. Type D Personality : a five-factor model perspective

    NARCIS (Netherlands)

    de Fruyt, F.; Denollet, J.K.L.

    2002-01-01

    This study investigated the position of Type D (high Negative Affectivity and high Social Inhibition) within the Five-Factor Model (FFM) of personality. A sample of 155 healthy subjects were administered the Type D Scale and the NEO-FFI, assessing the FFM traits. Subjects also filled out the General

  16. The Five-Factor Model of Personality and Career Success.

    Science.gov (United States)

    Seibert, Scott E.; Kraimer, Maria L.

    2001-01-01

    Measures of career success and an inventory of the Five-Factor Model of Personality were completed by 496 workers. Extraversion was related positively to salary, promotion, and career satisfaction; neuroticism was related negatively to satisfaction. A significant negative relationship between agreeableness and salary was found for workers in…

  17. A temperature dependent slip factor based thermal model for friction ...

    Indian Academy of Sciences (India)

    thermal modelling of FSW process by assuming the slip factor as a function of any one of the parameters such as ... Normal load, Fn. 31138 N .... source was moved in discrete steps of 1 mm to simulate the linear motion of the tool. At each load.

  18. Mathematical models for prediction of safety factors for a simply ...

    African Journals Online (AJOL)

    From the results obtained, mathematical prediction models were developed using a least square regression analysis for bending, shear and deflection modes of failure considered in the study. The results showed that the safety factors for material, dead and live load are not unique, but they are influenced by safety index ...

  19. The Five-Factor Model and Self-Determination Theory

    DEFF Research Database (Denmark)

    Olesen, Martin Hammershøj; Thomsen, Dorthe Kirkegaard; Schnieber, Anette

    This study investigates conceptual overlap vs. distinction between individual differences in personality traits, i.e. the Five-Factor Model; and Self-determination Theory, i.e. general causality orientations. Twelve-hundred-and-eighty-seven freshmen (mean age 21.71; 64% women) completed electronic...

  20. Reproductive Behavior and Personality Traits of the Five Factor Model

    NARCIS (Netherlands)

    Jokela, Markus; Alvergne, Alexandra; Pollet, Thomas V.; Lummaa, Virpi

    2011-01-01

    We examined associations between Five Factor Model personality traits and various outcomes of reproductive behavior in a sample of 15 729 women and men from the Wisconsin Longitudinal Study (WLS) and Midlife Development in the United States (MIDUS) survey. Personality and reproductive history was

  1. Risk factors and prognostic models for perinatal asphyxia at term

    NARCIS (Netherlands)

    Ensing, S.

    2015-01-01

    This thesis will focus on the risk factors and prognostic models for adverse perinatal outcome at term, with a special focus on perinatal asphyxia and obstetric interventions during labor to reduce adverse pregnancy outcomes. For the majority of the studies in this thesis we were allowed to use data

  2. Bayes Factor Covariance Testing in Item Response Models.

    Science.gov (United States)

    Fox, Jean-Paul; Mulder, Joris; Sinharay, Sandip

    2017-12-01

    Two marginal one-parameter item response theory models are introduced, by integrating out the latent variable or random item parameter. It is shown that both marginal response models are multivariate (probit) models with a compound symmetry covariance structure. Several common hypotheses concerning the underlying covariance structure are evaluated using (fractional) Bayes factor tests. The support for a unidimensional factor (i.e., assumption of local independence) and differential item functioning are evaluated by testing the covariance components. The posterior distribution of common covariance components is obtained in closed form by transforming latent responses with an orthogonal (Helmert) matrix. This posterior distribution is defined as a shifted-inverse-gamma, thereby introducing a default prior and a balanced prior distribution. Based on that, an MCMC algorithm is described to estimate all model parameters and to compute (fractional) Bayes factor tests. Simulation studies are used to show that the (fractional) Bayes factor tests have good properties for testing the underlying covariance structure of binary response data. The method is illustrated with two real data studies.

  3. A Two-Factor Model Better Explains Heterogeneity in Negative Symptoms: Evidence from the Positive and Negative Syndrome Scale.

    Science.gov (United States)

    Jang, Seon-Kyeong; Choi, Hye-Im; Park, Soohyun; Jaekal, Eunju; Lee, Ga-Young; Cho, Young Il; Choi, Kee-Hong

    2016-01-01

    Acknowledging separable factors underlying negative symptoms may lead to better understanding and treatment of negative symptoms in individuals with schizophrenia. The current study aimed to test whether the negative symptoms factor (NSF) of the Positive and Negative Syndrome Scale (PANSS) would be better represented by expressive and experiential deficit factors, rather than by a single factor model, using confirmatory factor analysis (CFA). Two hundred and twenty individuals with schizophrenia spectrum disorders completed the PANSS; subsamples additionally completed the Brief Negative Symptom Scale (BNSS) and the Motivation and Pleasure Scale-Self-Report (MAP-SR). CFA results indicated that the two-factor model fit the data better than the one-factor model; however, latent variables were closely correlated. The two-factor model's fit was significantly improved by accounting for correlated residuals between N2 (emotional withdrawal) and N6 (lack of spontaneity and flow of conversation), and between N4 (passive social withdrawal) and G16 (active social avoidance), possibly reflecting common method variance. The two NSF factors exhibited differential patterns of correlation with subdomains of the BNSS and MAP-SR. These results suggest that the PANSS NSF would be better represented by a two-factor model than by a single-factor one, and support the two-factor model's adequate criterion-related validity. Common method variance among several items may be a potential source of measurement error under a two-factor model of the PANSS NSF.

  4. Orchestrated regulation of Nogo receptors, LOTUS, AMPA receptors and BDNF in an ECT model suggests opening and closure of a window of synaptic plasticity.

    Directory of Open Access Journals (Sweden)

    Max Nordgren

    Full Text Available Electroconvulsive therapy (ECT is an efficient and relatively fast acting treatment for depression. However, one severe side effect of the treatment is retrograde amnesia, which in certain cases can be long-term. The mechanisms behind the antidepressant effect and the amnesia are not well understood. We hypothesized that ECT causes transient downregulation of key molecules needed to stabilize synaptic structure and to prevent Ca2+ influx, and a simultaneous increase in neurotrophic factors, thus providing a short time window of increased structural synaptic plasticity. Here we followed regulation of NgR1, NgR3, LOTUS, BDNF, and AMPA subunits GluR1 and GluR2 flip and flop mRNA levels in hippocampus at 2, 4, 12, 24, and 72 hours after a single episode of induced electroconvulsive seizures (ECS in rats. NgR1 and LOTUS mRNA levels were transiently downregulated in the dentate gyrus 2, 4, 12 and 4, 12, 24 h after ECS treatment, respectively. GluR2 flip, flop and GluR1 flop were downregulated at 4 h. GluR2 flip remained downregulated at 12 h. In contrast, BDNF, NgR3 and GluR1 flip mRNA levels were upregulated. Thus, ECS treatment induces a transient regulation of factors important for neuronal plasticity. Our data provide correlations between ECS treatment and molecular events compatible with the hypothesis that both effects and side effects of ECT may be caused by structural synaptic rearrangements.

  5. Physiological factors into plant uptake models for pollutant

    International Nuclear Information System (INIS)

    Goncharova, N.; Kalinkevich, E.; Pytyrskaya, V.; Lopareva, E.; Suvorov, D.

    2002-01-01

    The main principles of biological control of the intensity of pollutant flow into system soil-plant have been analysed. It demonstrated that functional state of plants is so far significant factor in determination of rate of pollutant turn on trophic chains as physical-chemical property of mineral elements Most biosphere and contamination assessment models are based on uniform soil conditions,since single coefficients are used to describe the transfer of contaminants to the plant. The main pathway of the functional control intensity of pollutant flow such as possibility of plant to increase mobility of mineral elements into soil and change of ion's exchange characteristics of plant tissues, which determine the degree of attraction and capacity of accumulation of non biogenic elements by a plant have been considered. It is known that there are two groups of factors which determine the level of pollutant accumulation by plant. The first group is connected with determination of the level of biological availability of pollutants for a plant in soil, the second group of factors determine attractive of the higher plants and capacity of radionuclides and heavy metals accumulation in biomass. At the same time in accordance with modern eco physiological data, different alive organisms can play active part in processes of the mineral elements migration. Metabolites of the coil microorganisms and especially root excretion of higher plants. Our investigations carried out earlier demonstrated that there is high correlation between the level of Cs, Cu, Zn and Co accumulation and cation exchange capacity of the intact plant tissues and on the other hand similar changes of these characteristics in condition of the experimental modification of radionuclide and heavy metals accumulation by different environmental factors. These data suggest that namely cation exchange capacity may be one of the main 'driving force' and physiological characteristics in absorption of non biogenic

  6. Mnemonic Discrimination Deficits in First-Episode Psychosis and a Ketamine Model Suggests Dentate Gyrus Pathology Linked to N-Methyl-D-Aspartate Receptor Hypofunction.

    Science.gov (United States)

    Kraguljac, Nina Vanessa; Carle, Matthew; Frölich, Michael A; Tran, Steve; Yassa, Michael A; White, David Matthew; Reddy, Abhishek; Lahti, Adrienne Carol

    2018-03-01

    Converging evidence from neuroimaging and postmortem studies suggests that hippocampal subfields are differentially affected in schizophrenia. Recent studies report dentate gyrus dysfunction in chronic schizophrenia, but the underlying mechanisms remain to be elucidated. Here we sought to examine if this deficit is already present in first-episode psychosis, and if N-methyl-D-aspartate receptor hypofunction, a putative central pathophysiological mechanism in schizophrenia, experimentally induced by ketamine, would result in a similar abnormality. We applied a mnemonic discrimination task selectively taxing pattern separation in two experiments: 1) a group of 23 first-episode psychosis patients and 23 matched healthy volunteers and 2) a group of 19 healthy volunteers before and during a ketamine challenge (0.27 mg/kg over 10 minutes, then 0.25 mg/kg/hour for 50 minutes, 0.01 mL/s). We calculated response bias-corrected pattern separation and recognition scores. We also examined the relationships between task performance and symptom severity as well as ketamine levels. We report a deficit in pattern separation but not recognition performance in first-episode psychosis patients compared with healthy volunteers (p = .04) and in volunteers during the ketamine challenge compared with baseline (p = .003). Exploratory analyses revealed no correlation between task performance and Repeatable Battery for the Assessment of Neuropsychological Status total scores or positive symptoms in first-episode psychosis patients, or with ketamine serum levels. We observed a mnemonic discrimination deficit but intact recognition in both datasets. Our findings suggest a tentative mechanistic link between dentate gyrus dysfunction in first-episode psychosis and N-methyl-D-aspartate receptor hypofunction. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  7. Free-free Gaunt factors: comparison of various models

    International Nuclear Information System (INIS)

    Collins, L.A.; Merts, A.L.

    1986-01-01

    We develop the general theory of free-free absorption processes in terms of basic quantum mechanical principles. We perform calculations of the free-free Gaunt factor for several models of the electron-atom (ion) interaction in a variety of systems including rare gases, alkali, and aluminum. In addition, we investigate plasma-screening effects in such models as the Yukawa potential. Our calculations compare well with those of other authors, and our comparative study of various models allows a more thorough understanding of their range of validity. 38 refs., 2 figs., 14 tabs

  8. Occam factors and model independent Bayesian learning of continuous distributions

    International Nuclear Information System (INIS)

    Nemenman, Ilya; Bialek, William

    2002-01-01

    Learning of a smooth but nonparametric probability density can be regularized using methods of quantum field theory. We implement a field theoretic prior numerically, test its efficacy, and show that the data and the phase space factors arising from the integration over the model space determine the free parameter of the theory ('smoothness scale') self-consistently. This persists even for distributions that are atypical in the prior and is a step towards a model independent theory for learning continuous distributions. Finally, we point out that a wrong parametrization of a model family may sometimes be advantageous for small data sets

  9. Hadron form factors in the constituent quark model

    International Nuclear Information System (INIS)

    Cardarelli, F.; Salme', G.; Simula, S.; Pace, E.

    1998-01-01

    Hadron electromagnetic form factors are evaluated in a light-front constituent quark model based on the eigenfunctions of a mass operator, including in the q-q interaction a confining term and a one-gluon-exchange term (OGE). The spin-dependent part of the interaction plays an essential role for obtaining both a proper fit of the experimental nucleon electromagnetic form factors and the faster than dipole decrease of the magnetic N-P 33 (1232) transition form factor. The effects of the D wave, produced by the tensor part of the OGE interaction, on the quadrupole and Coulomb N-P 33 (1232) transition form factors have been found to be negligible. (author)

  10. Optimal experimental design in an epidermal growth factor receptor signalling and down-regulation model.

    Science.gov (United States)

    Casey, F P; Baird, D; Feng, Q; Gutenkunst, R N; Waterfall, J J; Myers, C R; Brown, K S; Cerione, R A; Sethna, J P

    2007-05-01

    We apply the methods of optimal experimental design to a differential equation model for epidermal growth factor receptor signalling, trafficking and down-regulation. The model incorporates the role of a recently discovered protein complex made up of the E3 ubiquitin ligase, Cbl, the guanine exchange factor (GEF), Cool-1 (beta -Pix) and the Rho family G protein Cdc42. The complex has been suggested to be important in disrupting receptor down-regulation. We demonstrate that the model interactions can accurately reproduce the experimental observations, that they can be used to make predictions with accompanying uncertainties, and that we can apply ideas of optimal experimental design to suggest new experiments that reduce the uncertainty on unmeasurable components of the system.

  11. Form factors in the projected linear chiral sigma model

    International Nuclear Information System (INIS)

    Alberto, P.; Coimbra Univ.; Bochum Univ.; Ruiz Arriola, E.; Fiolhais, M.; Urbano, J.N.; Coimbra Univ.; Goeke, K.; Gruemmer, F.; Bochum Univ.

    1990-01-01

    Several nucleon form factors are computed within the framework of the linear chiral soliton model. To this end variational means and projection techniques applied to generalized hedgehog quark-boson Fock states are used. In this procedure the Goldberger-Treiman relation and a virial theorem for the pion-nucleon form factor are well fulfilled demonstrating the consistency of the treatment. Both proton and neutron charge form factors are correctly reproduced, as well as the proton magnetic one. The shapes of the neutron magnetic and of the axial form factors are good but their absolute values at the origin are too large. The slopes of all the form factors at zero momentum transfer are in good agreement with the experimental data. The pion-nucleon form factor exhibits to great extent a monopole shape with a cut-off mass of Λ=690 MeV. Electromagnetic form factors for the vertex γNΔ and the nucleon spin distribution are also evaluated and discussed. (orig.)

  12. The Barrett–Crane model: asymptotic measure factor

    International Nuclear Information System (INIS)

    Kamiński, Wojciech; Steinhaus, Sebastian

    2014-01-01

    The original spin foam model construction for 4D gravity by Barrett and Crane suffers from a few troubling issues. In the simple examples of the vertex amplitude they can be summarized as the existence of contributions to the asymptotics from non-geometric configurations. Even restricted to geometric contributions the amplitude is not completely worked out. While the phase is known to be the Regge action, the so-called measure factor has remained mysterious for a decade. In the toy model case of the 6j symbol this measure factor has a nice geometric interpretation of V −1/2 leading to speculations that a similar interpretation should be possible also in the 4D case. In this paper we provide the first geometric interpretation of the geometric part of the asymptotic for the spin foam consisting of two glued 4-simplices (decomposition of the 4-sphere) in the Barrett–Crane model in the large internal spin regime. (paper)

  13. The Barrett-Crane model: asymptotic measure factor

    Science.gov (United States)

    Kamiński, Wojciech; Steinhaus, Sebastian

    2014-04-01

    The original spin foam model construction for 4D gravity by Barrett and Crane suffers from a few troubling issues. In the simple examples of the vertex amplitude they can be summarized as the existence of contributions to the asymptotics from non-geometric configurations. Even restricted to geometric contributions the amplitude is not completely worked out. While the phase is known to be the Regge action, the so-called measure factor has remained mysterious for a decade. In the toy model case of the 6j symbol this measure factor has a nice geometric interpretation of V-1/2 leading to speculations that a similar interpretation should be possible also in the 4D case. In this paper we provide the first geometric interpretation of the geometric part of the asymptotic for the spin foam consisting of two glued 4-simplices (decomposition of the 4-sphere) in the Barrett-Crane model in the large internal spin regime.

  14. Multi-factor energy price models and exotic derivatives pricing

    Science.gov (United States)

    Hikspoors, Samuel

    The high pace at which many of the world's energy markets have gradually been opened to competition have generated a significant amount of new financial activity. Both academicians and practitioners alike recently started to develop the tools of energy derivatives pricing/hedging as a quantitative topic of its own. The energy contract structures as well as their underlying asset properties set the energy risk management industry apart from its more standard equity and fixed income counterparts. This thesis naturally contributes to these broad market developments in participating to the advances of the mathematical tools aiming at a better theory of energy contingent claim pricing/hedging. We propose many realistic two-factor and three-factor models for spot and forward price processes that generalize some well known and standard modeling assumptions. We develop the associated pricing methodologies and propose stable calibration algorithms that motivate the application of the relevant modeling schemes.

  15. A test of resuspension factor models against Chernobyl data

    International Nuclear Information System (INIS)

    Garger, E.K.; Hoffman, F.O.

    1995-04-01

    After the accident at Unit 4 of the Chernobyl nuclear power plant (NPP), stationary air samplers were operated at Chernobyl and Baryshevka, cities which are 16 km and 150 km, respectively, from the NPP. Other air samplers were operated simultaneously, but intermittently, at locations within the 30 km zone at distances of 4-25 km from the NPP. These data were used to check the validity of time dependent models of the resuspension factor K (m -1 ). Seven different models were examined, three of which are discussed in the paper. Data from the stationary air samplers were averaged over one day or one month; dam from the intermittent air samplers were averaged over three days in 1986 and over four hours in 1991. The concentrations of eight radionuclides were measured at ten points during the same time period (14-17 September 1986). The calculated resuspension factors range from 6 x 10 -9 m -1 to 3 x 10 -6 m -1 . Data for the spatial means of K are given for certain time periods in 1986 and 1991; also presented are the calculated values according to the models. The experimental data and the calculated values differ by up to more than one order of magnitude. Also analysed was the temporal change in experimental values of K and these values were compared with model predictions. The annual means of the resuspension factor as determined experimentally and as calculated with the models are presented. The model derived from empirical data measured in Neuherberg after the Chernobyl accident agrees best with the data. The Garland model systematically gives results lower than the experimental values, and the calculated values of K from the Linsley model are consistently conservative. Also considered were the uncertainty of K due to fluctuations in air concentrations and possible biological effects of episodic exposures

  16. A test of resuspension factor models against Chernobyl data

    Energy Technology Data Exchange (ETDEWEB)

    Garger, E.K. [Ukrainian Academy of Agricultural Sciences, Kiev (Ukraine). Inst. of Radioecology; Anspaugh, L.R.; Shinn, J.H. [Lawrence Livermore National Lab., CA (United States); Hoffman, F.O. [Senes Oak Ridge, Inc., TN (United States)

    1995-04-01

    After the accident at Unit 4 of the Chernobyl nuclear power plant (NPP), stationary air samplers were operated at Chernobyl and Baryshevka, cities which are 16 km and 150 km, respectively, from the NPP. Other air samplers were operated simultaneously, but intermittently, at locations within the 30 km zone at distances of 4-25 km from the NPP. These data were used to check the validity of time dependent models of the resuspension factor K (m{sup -1}). Seven different models were examined, three of which are discussed in the paper. Data from the stationary air samplers were averaged over one day or one month; dam from the intermittent air samplers were averaged over three days in 1986 and over four hours in 1991. The concentrations of eight radionuclides were measured at ten points during the same time period (14-17 September 1986). The calculated resuspension factors range from 6 x 10{sup -9} m{sup -1} to 3 x 10{sup -6} m{sup -1}. Data for the spatial means of K are given for certain time periods in 1986 and 1991; also presented are the calculated values according to the models. The experimental data and the calculated values differ by up to more than one order of magnitude. Also analysed was the temporal change in experimental values of K and these values were compared with model predictions. The annual means of the resuspension factor as determined experimentally and as calculated with the models are presented. The model derived from empirical data measured in Neuherberg after the Chernobyl accident agrees best with the data. The Garland model systematically gives results lower than the experimental values, and the calculated values of K from the Linsley model are consistently conservative. Also considered were the uncertainty of K due to fluctuations in air concentrations and possible biological effects of episodic exposures.

  17. Theoretical Assessment of the Impact of Climatic Factors in a Vibrio Cholerae Model.

    Science.gov (United States)

    Kolaye, G; Damakoa, I; Bowong, S; Houe, R; Békollè, D

    2018-05-04

    A mathematical model for Vibrio Cholerae (V. Cholerae) in a closed environment is considered, with the aim of investigating the impact of climatic factors which exerts a direct influence on the bacterial metabolism and on the bacterial reservoir capacity. We first propose a V. Cholerae mathematical model in a closed environment. A sensitivity analysis using the eFast method was performed to show the most important parameters of the model. After, we extend this V. cholerae model by taking account climatic factors that influence the bacterial reservoir capacity. We present the theoretical analysis of the model. More precisely, we compute equilibria and study their stabilities. The stability of equilibria was investigated using the theory of periodic cooperative systems with a concave nonlinearity. Theoretical results are supported by numerical simulations which further suggest the necessity to implement sanitation campaigns of aquatic environments by using suitable products against the bacteria during the periods of growth of aquatic reservoirs.

  18. Auditory function in the Tc1 mouse model of down syndrome suggests a limited region of human chromosome 21 involved in otitis media.

    Directory of Open Access Journals (Sweden)

    Stephanie Kuhn

    Full Text Available Down syndrome is one of the most common congenital disorders leading to a wide range of health problems in humans, including frequent otitis media. The Tc1 mouse carries a significant part of human chromosome 21 (Hsa21 in addition to the full set of mouse chromosomes and shares many phenotypes observed in humans affected by Down syndrome with trisomy of chromosome 21. However, it is unknown whether Tc1 mice exhibit a hearing phenotype and might thus represent a good model for understanding the hearing loss that is common in Down syndrome. In this study we carried out a structural and functional assessment of hearing in Tc1 mice. Auditory brainstem response (ABR measurements in Tc1 mice showed normal thresholds compared to littermate controls and ABR waveform latencies and amplitudes were equivalent to controls. The gross anatomy of the middle and inner ears was also similar between Tc1 and control mice. The physiological properties of cochlear sensory receptors (inner and outer hair cells: IHCs and OHCs were investigated using single-cell patch clamp recordings from the acutely dissected cochleae. Adult Tc1 IHCs exhibited normal resting membrane potentials and expressed all K(+ currents characteristic of control hair cells. However, the size of the large conductance (BK Ca(2+ activated K(+ current (I(K,f, which enables rapid voltage responses essential for accurate sound encoding, was increased in Tc1 IHCs. All physiological properties investigated in OHCs were indistinguishable between the two genotypes. The normal functional hearing and the gross structural anatomy of the middle and inner ears in the Tc1 mouse contrast to that observed in the Ts65Dn model of Down syndrome which shows otitis media. Genes that are trisomic in Ts65Dn but disomic in Tc1 may predispose to otitis media when an additional copy is active.

  19. Neuroprotective effects of the anti-cancer drug sunitinib in models of HIV neurotoxicity suggests potential for the treatment of neurodegenerative disorders.

    Science.gov (United States)

    Wrasidlo, Wolf; Crews, Leslie A; Tsigelny, Igor F; Stocking, Emily; Kouznetsova, Valentina L; Price, Diana; Paulino, Amy; Gonzales, Tania; Overk, Cassia R; Patrick, Christina; Rockenstein, Edward; Masliah, Eliezer

    2014-12-01

    Anti-retrovirals have improved and extended the life expectancy of patients with HIV. However, as this population ages, the prevalence of cognitive changes is increasing. Aberrant activation of kinases, such as receptor tyrosine kinases (RTKs) and cyclin-dependent kinase 5 (CDK5), play a role in the mechanisms of HIV neurotoxicity. Inhibitors of CDK5, such as roscovitine, have neuroprotective effects; however, CNS penetration is low. Interestingly, tyrosine kinase inhibitors (TKIs) display some CDK inhibitory activity and ability to cross the blood-brain barrier. We screened a small group of known TKIs for a candidate with additional CDK5 inhibitory activity and tested the efficacy of the candidate in in vitro and in vivo models of HIV-gp120 neurotoxicity. Among 12 different compounds, sunitinib inhibited CDK5 with an IC50 of 4.2 μM. In silico analysis revealed that, similarly to roscovitine, sunitinib fitted 6 of 10 features of the CDK5 pharmacophore. In a cell-based model, sunitinib reduced CDK5 phosphorylation (pCDK5), calpain-dependent p35/p25 conversion and protected neuronal cells from the toxic effects of gp120. In glial fibrillary acidic protein-gp120 transgenic (tg) mice, sunitinib reduced levels of pCDK5, p35/p25 and phosphorylated tau protein, along with amelioration of the neurodegenerative pathology. Compounds such as sunitinib with dual kinase inhibitory activity could ameliorate the cognitive impairment associated with chronic HIV infection of the CNS. Moreover, repositioning existing low MW compounds holds promise for the treatment of patients with neurodegenerative disorders. © 2014 The British Pharmacological Society.

  20. Human Factor Modelling in the Risk Assessment of Port Manoeuvers

    Directory of Open Access Journals (Sweden)

    Teresa Abramowicz-Gerigk

    2015-09-01

    Full Text Available The documentation of human factor influence on the scenario development in maritime accidents compared with expert methods is commonly used as a basis in the process of setting up safety regulations and instructions. The new accidents and near misses show the necessity for further studies in determining the human factor influence on both risk acceptance criteria and development of risk control options for the manoeuvers in restricted waters. The paper presents the model of human error probability proposed for the assessment of ship masters and marine pilots' error decision and its influence on the risk of port manoeuvres.

  1. Modeling of arylamide helix mimetics in the p53 peptide binding site of hDM2 suggests parallel and anti-parallel conformations are both stable.

    Directory of Open Access Journals (Sweden)

    Jonathan C Fuller

    Full Text Available The design of novel α-helix mimetic inhibitors of protein-protein interactions is of interest to pharmaceuticals and chemical genetics researchers as these inhibitors provide a chemical scaffold presenting side chains in the same geometry as an α-helix. This conformational arrangement allows the design of high affinity inhibitors mimicking known peptide sequences binding specific protein substrates. We show that GAFF and AutoDock potentials do not properly capture the conformational preferences of α-helix mimetics based on arylamide oligomers and identify alternate parameters matching solution NMR data and suitable for molecular dynamics simulation of arylamide compounds. Results from both docking and molecular dynamics simulations are consistent with the arylamides binding in the p53 peptide binding pocket. Simulations of arylamides in the p53 binding pocket of hDM2 are consistent with binding, exhibiting similar structural dynamics in the pocket as simulations of known hDM2 binders Nutlin-2 and a benzodiazepinedione compound. Arylamide conformations converge towards the same region of the binding pocket on the 20 ns time scale, and most, though not all dihedrals in the binding pocket are well sampled on this timescale. We show that there are two putative classes of binding modes for arylamide compounds supported equally by the modeling evidence. In the first, the arylamide compound lies parallel to the observed p53 helix. In the second class, not previously identified or proposed, the arylamide compound lies anti-parallel to the p53 helix.

  2. SHMF: Interest Prediction Model with Social Hub Matrix Factorization

    Directory of Open Access Journals (Sweden)

    Chaoyuan Cui

    2017-01-01

    Full Text Available With the development of social networks, microblog has become the major social communication tool. There is a lot of valuable information such as personal preference, public opinion, and marketing in microblog. Consequently, research on user interest prediction in microblog has a positive practical significance. In fact, how to extract information associated with user interest orientation from the constantly updated blog posts is not so easy. Existing prediction approaches based on probabilistic factor analysis use blog posts published by user to predict user interest. However, these methods are not very effective for the users who post less but browse more. In this paper, we propose a new prediction model, which is called SHMF, using social hub matrix factorization. SHMF constructs the interest prediction model by combining the information of blogs posts published by both user and direct neighbors in user’s social hub. Our proposed model predicts user interest by integrating user’s historical behavior and temporal factor as well as user’s friendships, thus achieving accurate forecasts of user’s future interests. The experimental results on Sina Weibo show the efficiency and effectiveness of our proposed model.

  3. Modeling Factors with Influence on Sustainable University Management

    Directory of Open Access Journals (Sweden)

    Oana Dumitrascu

    2015-01-01

    Full Text Available The main objective of this paper is to present the factors with influence on the sustainable university management and the relationships between them. In the scientific approach we begin from a graphical model, according to which the extracurricular activities together with internal environmental factors influence students’ involvement in such activities, the university attractiveness, their academic performance and their integration into the socially-economic and natural environment (components related with sustainable development. The model emphasizes that individual performances, related to students’ participation in extracurricular activities, have a positive influence on the sustainability of university management. The results of the study have shown that the university sustainability may be influenced by a number of factors, such as students’ performance, students’ involvement in extracurricular activities or university’s attractiveness and can in turn influence implicitly also the sustainability of university management. The originality of the paper consists in the relationships study using the modeling method in general and informatics tools of modeling in particular, as well as through graphical visualization of some influences, on the sustainability university management.

  4. Bayes factor between Student t and Gaussian mixed models within an animal breeding context

    Directory of Open Access Journals (Sweden)

    García-Cortés Luis

    2008-07-01

    Full Text Available Abstract The implementation of Student t mixed models in animal breeding has been suggested as a useful statistical tool to effectively mute the impact of preferential treatment or other sources of outliers in field data. Nevertheless, these additional sources of variation are undeclared and we do not know whether a Student t mixed model is required or if a standard, and less parameterized, Gaussian mixed model would be sufficient to serve the intended purpose. Within this context, our aim was to develop the Bayes factor between two nested models that only differed in a bounded variable in order to easily compare a Student t and a Gaussian mixed model. It is important to highlight that the Student t density converges to a Gaussian process when degrees of freedom tend to infinity. The twomodels can then be viewed as nested models that differ in terms of degrees of freedom. The Bayes factor can be easily calculated from the output of a Markov chain Monte Carlo sampling of the complex model (Student t mixed model. The performance of this Bayes factor was tested under simulation and on a real dataset, using the deviation information criterion (DIC as the standard reference criterion. The two statistical tools showed similar trends along the parameter space, although the Bayes factor appeared to be the more conservative. There was considerable evidence favoring the Student t mixed model for data sets simulated under Student t processes with limited degrees of freedom, and moderate advantages associated with using the Gaussian mixed model when working with datasets simulated with 50 or more degrees of freedom. For the analysis of real data (weight of Pietrain pigs at six months, both the Bayes factor and DIC slightly favored the Student t mixed model, with there being a reduced incidence of outlier individuals in this population.

  5. Condensation in models with factorized and pair-factorized stationary states

    International Nuclear Information System (INIS)

    Evans, M R; Waclaw, B

    2015-01-01

    Non-equilibrium real-space condensation is a phenomenon in which a finite fraction of some conserved quantity (mass, particles, etc) becomes spatially localized. We review two popular stochastic models of hopping particles that lead to condensation and whose stationary states assume a factorized form: the zero-range process and the misanthrope process, and their various generalizations. We also introduce a new model—a misanthrope process with parallel dynamics—that exhibits condensation and has a pair-factorized stationary state

  6. The Factors of Forming the National HR-Management Model

    Directory of Open Access Journals (Sweden)

    Elena P. Kostenko

    2017-12-01

    Full Text Available There are some factors considered in this article, which influence the forming of national HR-management model. The group-forming criterion is the nature of factors, that determine the system of HR-management as a system of corporate culture values, norms and rules of organizational behavior, ways of realization some important managing functions and dominating approaches to make decisions. This article shows that the plurality of combinations in different factors leads to forming the unique HR-management model. The geoclimatic factor influences the principles of the labor organization (orientation primarily on individual or collective forms of labor, attitude to the management experience of other countries, attitude to resources, etc., the distribution of labor resources, the level of labor mobility, and the psychosocial type of employee. Models of man's labor behavior are constituted In the process of historical development. Attention is focused on the formation of a national HR-model, such as the conducted socio-economic policy, the characteristics of the institutional environment, economic goals and priorities of the country's development, the level of development and the nature of the national productive forces and economic structures. Much attention was paid to the analysis of the historically formed value system and labor traditions, which influence the approaches to HR-management. As far as religion influences the model of person’s inclusion in labor, motives of labor behavior, management culture of a certain employee, preferred payment etc., we examined how the main traditional religions (Christianity, Islam, Judaism, Buddhism, Confucianism, Hinduism influence the HR-management system in different countries.

  7. Factors affecting strategic plan implementation using interpretive structural modeling (ISM).

    Science.gov (United States)

    Bahadori, Mohammadkarim; Teymourzadeh, Ehsan; Tajik, Hamidreza; Ravangard, Ramin; Raadabadi, Mehdi; Hosseini, Seyed Mojtaba

    2018-06-11

    Purpose Strategic planning is the best tool for managers seeking an informed presence and participation in the market without surrendering to changes. Strategic planning enables managers to achieve their organizational goals and objectives. Hospital goals, such as improving service quality and increasing patient satisfaction cannot be achieved if agreed strategies are not implemented. The purpose of this paper is to investigate the factors affecting strategic plan implementation in one teaching hospital using interpretive structural modeling (ISM). Design/methodology/approach The authors used a descriptive study involving experts and senior managers; 16 were selected as the study sample using a purposive sampling method. Data were collected using a questionnaire designed and prepared based on previous studies. Data were analyzed using ISM. Findings Five main factors affected strategic plan implementation. Although all five variables and factors are top level, "senior manager awareness and participation in the strategic planning process" and "creating and maintaining team participation in the strategic planning process" had maximum drive power. "Organizational structure effects on the strategic planning process" and "Organizational culture effects on the strategic planning process" had maximum dependence power. Practical implications Identifying factors affecting strategic plan implementation is a basis for healthcare quality improvement by analyzing the relationship among factors and overcoming the barriers. Originality/value The authors used ISM to analyze the relationship between factors affecting strategic plan implementation.

  8. Exploring key factors in online shopping with a hybrid model.

    Science.gov (United States)

    Chen, Hsiao-Ming; Wu, Chia-Huei; Tsai, Sang-Bing; Yu, Jian; Wang, Jiangtao; Zheng, Yuxiang

    2016-01-01

    Nowadays, the web increasingly influences retail sales. An in-depth analysis of consumer decision-making in the context of e-business has become an important issue for internet vendors. However, factors affecting e-business are complicated and intertwined. To stimulate online sales, understanding key influential factors and causal relationships among the factors is important. To gain more insights into this issue, this paper introduces a hybrid method, which combines the Decision Making Trial and Evaluation Laboratory (DEMATEL) with the analytic network process, called DANP method, to find out the driving factors that influence the online business mostly. By DEMATEL approach the causal graph showed that "online service" dimension has the highest degree of direct impact on other dimensions; thus, the internet vendor is suggested to made strong efforts on service quality throughout the online shopping process. In addition, the study adopted DANP to measure the importance of key factors, among which "transaction security" proves to be the most important criterion. Hence, transaction security should be treated with top priority to boost the online businesses. From our study with DANP approach, the comprehensive information can be visually detected so that the decision makers can spotlight on the root causes to develop effectual actions.

  9. A model-based telecoupling analysis for the Patagonian shelf: a new suggested template on how to study global seabirds-fisheries interactions for sustainability

    Science.gov (United States)

    Huettmann, F.; Raya Rey, A.

    2016-12-01

    The Southwest Atlantic Ocean, and the extended Patagonian shelf in particular, presents us with a very complex ecosystem of global relevance for food security and global peace. It is a highly productive area and it maintains a great diversity and abundance of seabird species. Fisheries have been identified as a main stressor for the marine ecosystems and as one of the main causes of seabird population declines. Using the framework of telecoupling - a sophisticated description of natural and socioeconomic interactions over large distances - here we present a fresh holistic look at the dynamic fisheries and (endangered) seabird interactions for the Patagonian shelf. While data are sparse, we employ machine learning-based predictions for a more holistic overview. We found that these waters of the Patagonian Shelf are significantly affected by many nations and outside players. We found that the input, output and spill-over of the Patagonian shelf ecosystem are distributed virtually all over the globe. In addition, we also found `losers' (=nations and their citizens that are left out entirely from this global resource and its governance). Our findings are based on best-available public trade and fish harvest analysis for this region, linked with predictive modeling (machine learning and geographic information systems GIS) to generalize for nine seabird species. We conveniently extend this analysis with a perspective from the financial sector and policy that enables the Patagonian fisheries as international investment and development projects. As increasingly recognized elsewhere, we believe that telecoupling can serve as a new but rather sophisticated study template highlighting wider complexities, bottlenecks and sensitivities for a vastly improved conservation research on oceans and global sustainability questions.

  10. Half-Life of Sulfonylureas in HNF1A and HNF4A Human MODY Patients is not Prolonged as Suggested by the Mouse Hnf1a(-/-) Model.

    Science.gov (United States)

    Urbanova, Jana; Andel, Michal; Potockova, Jana; Klima, Josef; Macek, Jan; Ptacek, Pavel; Mat'oska, Vaclav; Kumstyrova, Tereza; Heneberg, Petr

    2015-01-01

    Sulfonylurea derivatives are widely used for clinical treatment of human subjects with Maturity Onset Diabetes of the Young (MODY) caused by mutations in HNF-1α or HNF-4α despite the mechanism leading to their hypersensitivity is incompletely understood. In Hnf1a(-/-) mice, serum concentrations and half-life of sulfonylurea derivatives are strongly increased. We thus hypothesized that reduced sulfonylurea derivatives clearance stands behind their therapeutic potential in human HNF1A/HNF4A MODY subjects. Single doses of 3 mg glipizide and 5 mg glibenclamide/glyburide were administered sequentially to seven HNF1A/HNF4A MODY subjects and six control individuals matched for their age, BMI and CYP2C9 genotype. Pharmacokinetic (plasma concentration levels, Cmax, tmax, t1/2, AUC) and pharmacodynamic parameters (glycemia, C-peptide and insulin plasma levels) were followed for 24 hours after drug administration. We provide the first evidence on the pharmacokinetics and pharmacodynamics of sulfonylurea derivatives in human MODY subjects. The half-life of glipizide did not change, and reached 3.8±0.7 and 3.7±1.8 h in the MODY and control subjects, respectively. The half-life of glibenclamide was increased only in some MODY subjects (t1/2 9.5±6.7 and 5.0±1.4 h, respectively). Importantly, the intra- individual responses of MODY (but control) subjects to glipizide and glibenclamide treatment were highly correlated. With regards to pharmacodynamics, we observed a differential response of control but not MODY subjects to the doses of glipizide and glibenclamide applied. We rejected the hypothesis that all human MODY-associated mutations in HNF1A / HNF4A induce changes in the pharmacokinetics of sulfonylureas in humans analogically to the Hnf1a(-/-) mouse model.

  11. Molecular modeling and simulation studies of recombinant laccase from Yersinia enterocolitica suggests significant role in the biotransformation of non-steroidal anti-inflammatory drugs

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Deepti; Rawat, Surender [Laboratory of Enzymology and Recombinant DNA Technology, Department of Microbiology, Maharshi Dayanand University, Rohtak 124001, Haryana (India); Waseem, Mohd; Gupta, Sunita; Lynn, Andrew [School of Computational & Integrative Sciences, Jawaharlal Nehru University, New Delhi 110067 (India); Nitin, Mukesh; Ramchiary, Nirala [School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067 (India); Sharma, Krishna Kant, E-mail: kekulsharma@gmail.com [Laboratory of Enzymology and Recombinant DNA Technology, Department of Microbiology, Maharshi Dayanand University, Rohtak 124001, Haryana (India)

    2016-01-08

    The YacK gene from Yersinia enterocolitica strain 7, cloned in pET28a vector and expressed in Escherichia coli BL21 (DE3), showed laccase activity when oxidized with 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and guaiacol. The recombinant laccase protein was purified and characterized biochemically with a molecular mass of ≈58 KDa on SDS-PAGE and showed positive zymogram with ABTS. The protein was highly robust with optimum pH 9.0 and stable at 70 °C upto 12 h with residual activity of 70%. Kinetic constants, K{sub m} values, for ABTS and guaiacol were 675 μM and 2070 μM, respectively, with corresponding Vmax values of 0.125 μmol/ml/min and 6500 μmol/ml/min. It also possess antioxidative property against BSA and Cu{sup 2+}/H{sub 2}O{sub 2} model system. Constant pH MD simulation studies at different protonation states of the system showed ABTS to be most stable at acidic pH, whereas, diclofenac at neutral pH. Interestingly, aspirin drifted out of the binding pocket at acidic and neutral pH, but showed stable binding at alkaline pH. The biotransformation of diclofenac and aspirin by laccase also corroborated the in silico results. This is the first report on biotransformation of non-steroidal anti-inflammatory drugs (NSAIDs) using recombinant laccase from gut bacteria, supported by in silico simulation studies. - Highlights: • Laccase from Yersinia enterocolitica strain 7 was expressed in Escherichia coli BL21 (DE3). • Recombinant laccase was found to be thermostable and alkali tolerant. • The in silico and experimental studied proves the biotransformation of NSAIDs. • Laccase binds to ligands differentially under different protonation state. • Laccase also possesses free radical scavenging property.

  12. Molecular modeling and simulation studies of recombinant laccase from Yersinia enterocolitica suggests significant role in the biotransformation of non-steroidal anti-inflammatory drugs

    International Nuclear Information System (INIS)

    Singh, Deepti; Rawat, Surender; Waseem, Mohd; Gupta, Sunita; Lynn, Andrew; Nitin, Mukesh; Ramchiary, Nirala; Sharma, Krishna Kant

    2016-01-01

    The YacK gene from Yersinia enterocolitica strain 7, cloned in pET28a vector and expressed in Escherichia coli BL21 (DE3), showed laccase activity when oxidized with 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and guaiacol. The recombinant laccase protein was purified and characterized biochemically with a molecular mass of ≈58 KDa on SDS-PAGE and showed positive zymogram with ABTS. The protein was highly robust with optimum pH 9.0 and stable at 70 °C upto 12 h with residual activity of 70%. Kinetic constants, K m values, for ABTS and guaiacol were 675 μM and 2070 μM, respectively, with corresponding Vmax values of 0.125 μmol/ml/min and 6500 μmol/ml/min. It also possess antioxidative property against BSA and Cu 2+ /H 2 O 2 model system. Constant pH MD simulation studies at different protonation states of the system showed ABTS to be most stable at acidic pH, whereas, diclofenac at neutral pH. Interestingly, aspirin drifted out of the binding pocket at acidic and neutral pH, but showed stable binding at alkaline pH. The biotransformation of diclofenac and aspirin by laccase also corroborated the in silico results. This is the first report on biotransformation of non-steroidal anti-inflammatory drugs (NSAIDs) using recombinant laccase from gut bacteria, supported by in silico simulation studies. - Highlights: • Laccase from Yersinia enterocolitica strain 7 was expressed in Escherichia coli BL21 (DE3). • Recombinant laccase was found to be thermostable and alkali tolerant. • The in silico and experimental studied proves the biotransformation of NSAIDs. • Laccase binds to ligands differentially under different protonation state. • Laccase also possesses free radical scavenging property.

  13. Factor Analysis of Drawings: Application to college student models of the greenhouse effect

    Science.gov (United States)

    Libarkin, Julie C.; Thomas, Stephen R.; Ording, Gabriel

    2015-09-01

    Exploratory factor analysis was used to identify models underlying drawings of the greenhouse effect made by over 200 entering university freshmen. Initial content analysis allowed deconstruction of drawings into salient features, with grouping of these features via factor analysis. A resulting 4-factor solution explains 62% of the data variance, suggesting that 4 archetype models of the greenhouse effect dominate thinking within this population. Factor scores, indicating the extent to which each student's drawing aligned with representative models, were compared to performance on conceptual understanding and attitudes measures, demographics, and non-cognitive features of drawings. Student drawings were also compared to drawings made by scientists to ascertain the extent to which models reflect more sophisticated and accurate models. Results indicate that student and scientist drawings share some similarities, most notably the presence of some features of the most sophisticated non-scientific model held among the study population. Prior knowledge, prior attitudes, gender, and non-cognitive components are also predictive of an individual student's model. This work presents a new technique for analyzing drawings, with general implications for the use of drawings in investigating student conceptions.

  14. Integrative modeling of eQTLs and cis-regulatory elements suggests mechanisms underlying cell type specificity of eQTLs.

    Directory of Open Access Journals (Sweden)

    Christopher D Brown

    Full Text Available Genetic variants in cis-regulatory elements or trans-acting regulators frequently influence the quantity and spatiotemporal distribution of gene transcription. Recent interest in expression quantitative trait locus (eQTL mapping has paralleled the adoption of genome-wide association studies (GWAS for the analysis of complex traits and disease in humans. Under the hypothesis that many GWAS associations tag non-coding SNPs with small effects, and that these SNPs exert phenotypic control by modifying gene expression, it has become common to interpret GWAS associations using eQTL data. To fully exploit the mechanistic interpretability of eQTL-GWAS comparisons, an improved understanding of the genetic architecture and causal mechanisms of cell type specificity of eQTLs is required. We address this need by performing an eQTL analysis in three parts: first we identified eQTLs from eleven studies on seven cell types; then we integrated eQTL data with cis-regulatory element (CRE data from the ENCODE project; finally we built a set of classifiers to predict the cell type specificity of eQTLs. The cell type specificity of eQTLs is associated with eQTL SNP overlap with hundreds of cell type specific CRE classes, including enhancer, promoter, and repressive chromatin marks, regions of open chromatin, and many classes of DNA binding proteins. These associations provide insight into the molecular mechanisms generating the cell type specificity of eQTLs and the mode of regulation of corresponding eQTLs. Using a random forest classifier with cell specific CRE-SNP overlap as features, we demonstrate the feasibility of predicting the cell type specificity of eQTLs. We then demonstrate that CREs from a trait-associated cell type can be used to annotate GWAS associations in the absence of eQTL data for that cell type. We anticipate that such integrative, predictive modeling of cell specificity will improve our ability to understand the mechanistic basis of human

  15. A Novel In Vitro CypD-Mediated p53 Aggregation Assay Suggests a Model for Mitochondrial Permeability Transition by Chaperone Systems.

    Science.gov (United States)

    Lebedev, Ivan; Nemajerova, Alice; Foda, Zachariah H; Kornaj, Maja; Tong, Michael; Moll, Ute M; Seeliger, Markus A

    2016-10-09

    Tissue necrosis as a consequence of ischemia-reperfusion injury and oxidative damage is a leading cause of permanent disability and death worldwide. The complete mechanism by which cells undergo necrosis upon oxidative stress is not understood. In response to an oxidative insult, wild-type p53 has been implicated as a central regulatory component of the mitochondrial permeability transition (mPT), triggering necrosis. This process is associated with cellular stabilization and translocation of p53 into the mitochondrial matrix. Here, we probe the mechanism by which p53 activates the key mPT regulator cyclophilin D (CypD). We explore the involvement of Trap1, an Hsp90-related mitochondrial matrix protein and a member of the mitochondrial unfolded protein response, and its ability to suppress mPT in a p53-dependent manner. Our study finds that catalytically active CypD causes strong aggregation of wild-type p53 protein (both full-length and isolated DNA-binding domain) into amyloid-type fibrils in vitro. The responsible CypD residues for this activity were mapped by NMR to the active site amino acids R55, F60, F113, and W121. The data also present a new proline isomerization assay for CypD by monitoring the aggregation of p53 as an indicator of CypD activity. Moreover, we find that the inhibition of Trap1 by the mitochondria-specific HSP90 ATPase antagonist Gamitrinib strongly sensitizes primary mouse embryonic fibroblasts to mPT and permeability transition pore opening in a p53- and CypD-dependent manner. We propose a mechanism by which the influx of unfolded p53 into the mitochondrial matrix in response to oxidative stress indirectly activates the normally inhibited CypD by displacing it from Trap1 complexes. This activates CypD's isomerase activity. Liberated CypD then isomerizes multiple proteins including p53 (causing p53 aggregation) and the structural components of the mPTP pore, inducing pore opening. This working model can now be tested in the future

  16. Selection of asset investment models by hospitals: examination of influencing factors, using Switzerland as an example.

    Science.gov (United States)

    Eicher, Bernhard

    2016-10-01

    Hospitals are responsible for a remarkable part of the annual increase in healthcare expenditure. This article examines one of the major cost drivers, the expenditure for investment in hospital assets. The study, conducted in Switzerland, identifies factors that influence hospitals' investment decisions. A suggestion on how to categorize asset investment models is presented based on the life cycle of an asset, and its influencing factors defined based on transaction cost economics. The influence of five factors (human asset specificity, physical asset specificity, uncertainty, bargaining power, and privacy of ownership) on the selection of an asset investment model is examined using a two-step fuzzy-set Qualitative Comparative Analysis. The research shows that outsourcing-oriented asset investment models are particularly favored in the presence of two combinations of influencing factors: First, if technological uncertainty is high and both human asset specificity and bargaining power of a hospital are low. Second, if assets are very specific, technological uncertainty is high and there is a private hospital with low bargaining power, outsourcing-oriented asset investment models are favored too. Using Qualitative Comparative Analysis, it can be demonstrated that investment decisions of hospitals do not depend on isolated influencing factors but on a combination of factors. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  17. Finite-lattice form factors in free-fermion models

    International Nuclear Information System (INIS)

    Iorgov, N; Lisovyy, O

    2011-01-01

    We consider the general Z 2 -symmetric free-fermion model on the finite periodic lattice, which includes as special cases the Ising model on the square and triangular lattices and the Z n -symmetric BBS τ (2) -model with n = 2. Translating Kaufman's fermionic approach to diagonalization of Ising-like transfer matrices into the language of Grassmann integrals, we determine the transfer matrix eigenvectors and observe that they coincide with the eigenvectors of a square lattice Ising transfer matrix. This allows us to find exact finite-lattice form factors of spin operators for the statistical model and the associated finite-length quantum chains, of which the most general is equivalent to the XY chain in a transverse field

  18. A general psychopathology factor (P factor) in children: Structural model analysis and external validation through familial risk and child global executive function.

    Science.gov (United States)

    Martel, Michelle M; Pan, Pedro M; Hoffmann, Maurício S; Gadelha, Ary; do Rosário, Maria C; Mari, Jair J; Manfro, Gisele G; Miguel, Eurípedes C; Paus, Tomás; Bressan, Rodrigo A; Rohde, Luis A; Salum, Giovanni A

    2017-01-01

    High rates of comorbidities and poor validity of disorder diagnostic criteria for mental disorders hamper advances in mental health research. Recent work has suggested the utility of continuous cross-cutting dimensions, including general psychopathology and specific factors of externalizing and internalizing (e.g., distress and fear) syndromes. The current study evaluated the reliability of competing structural models of psychopathology and examined external validity of the best fitting model on the basis of family risk and child global executive function (EF). A community sample of 8,012 families from Brazil with children ages 6-12 years completed structured interviews about the child and parental psychiatric syndromes, and a subsample of 2,395 children completed tasks assessing EF (i.e., working memory, inhibitory control, and time processing). Confirmatory factor analyses tested a series of structural models of psychopathology in both parents and children. The model with a general psychopathology factor ("P factor") with 3 specific factors (fear, distress, and externalizing) exhibited the best fit. The general P factor accounted for most of the variance in all models, with little residual variance explained by each of the 3 specific factors. In addition, associations between child and parental factors were mainly significant for the P factors and nonsignificant for the specific factors from the respective models. Likewise, the child P factor-but not the specific factors-was significantly associated with global child EF. Overall, our results provide support for a latent overarching P factor characterizing child psychopathology, supported by familial associations and child EF. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  19. Estimating safety effects of pavement management factors utilizing Bayesian random effect models.

    Science.gov (United States)

    Jiang, Ximiao; Huang, Baoshan; Zaretzki, Russell L; Richards, Stephen; Yan, Xuedong

    2013-01-01

    Previous studies of pavement management factors that relate to the occurrence of traffic-related crashes are rare. Traditional research has mostly employed summary statistics of bidirectional pavement quality measurements in extended longitudinal road segments over a long time period, which may cause a loss of important information and result in biased parameter estimates. The research presented in this article focuses on crash risk of roadways with overall fair to good pavement quality. Real-time and location-specific data were employed to estimate the effects of pavement management factors on the occurrence of crashes. This research is based on the crash data and corresponding pavement quality data for the Tennessee state route highways from 2004 to 2009. The potential temporal and spatial correlations among observations caused by unobserved factors were considered. Overall 6 models were built accounting for no correlation, temporal correlation only, and both the temporal and spatial correlations. These models included Poisson, negative binomial (NB), one random effect Poisson and negative binomial (OREP, ORENB), and two random effect Poisson and negative binomial (TREP, TRENB) models. The Bayesian method was employed to construct these models. The inference is based on the posterior distribution from the Markov chain Monte Carlo (MCMC) simulation. These models were compared using the deviance information criterion. Analysis of the posterior distribution of parameter coefficients indicates that the pavement management factors indexed by Present Serviceability Index (PSI) and Pavement Distress Index (PDI) had significant impacts on the occurrence of crashes, whereas the variable rutting depth was not significant. Among other factors, lane width, median width, type of terrain, and posted speed limit were significant in affecting crash frequency. The findings of this study indicate that a reduction in pavement roughness would reduce the likelihood of traffic

  20. Baryon octet electromagnetic form factors in a confining NJL model

    Directory of Open Access Journals (Sweden)

    Manuel E. Carrillo-Serrano

    2016-08-01

    Full Text Available Electromagnetic form factors of the baryon octet are studied using a Nambu–Jona-Lasinio model which utilizes the proper-time regularization scheme to simulate aspects of colour confinement. In addition, the model also incorporates corrections to the dressed quarks from vector meson correlations in the t-channel and the pion cloud. Comparison with recent chiral extrapolations of lattice QCD results shows a remarkable level of consistency. For the charge radii we find the surprising result that rEp

  1. Modeling impact of environmental factors on photovoltaic array performance

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jie; Sun, Yize; Xu, Yang [College of Mechanical Engineering, Donghua University NO.2999, North Renmin Road, Shanghai (China)

    2013-07-01

    It is represented in this paper that a methodology to model and quantify the impact of the three environmental factors, the ambient temperature, the incident irradiance and the wind speed, upon the performance of photovoltaic array operating under outdoor conditions. First, A simple correlation correlating operating temperature with the three environmental variables is validated for a range of wind speed studied, 2-8, and for irradiance values between 200 and 1000. Root mean square error (RMSE) between modeled operating temperature and measured values is 1.19% and the mean bias error (MBE) is -0.09%. The environmental factors studied influence I-V curves, P-V curves, and maximum-power outputs of photovoltaic array. The cell-to-module-to-array mathematical model for photovoltaic panels is established in this paper and the method defined as segmented iteration is adopted to solve the I-V curve expression to relate model I-V curves. The model I-V curves and P-V curves are concluded to coincide well with measured data points. The RMSE between numerically calculated maximum-power outputs and experimentally measured ones is 0.2307%, while the MBE is 0.0183%. In addition, a multivariable non-linear regression equation is proposed to eliminate the difference between numerically calculated values and measured ones of maximum power outputs over the range of high ambient temperature and irradiance at noon and in the early afternoon. In conclusion, the proposed method is reasonably simple and accurate.

  2. Model Fit and Item Factor Analysis: Overfactoring, Underfactoring, and a Program to Guide Interpretation.

    Science.gov (United States)

    Clark, D Angus; Bowles, Ryan P

    2018-04-23

    In exploratory item factor analysis (IFA), researchers may use model fit statistics and commonly invoked fit thresholds to help determine the dimensionality of an assessment. However, these indices and thresholds may mislead as they were developed in a confirmatory framework for models with continuous, not categorical, indicators. The present study used Monte Carlo simulation methods to investigate the ability of popular model fit statistics (chi-square, root mean square error of approximation, the comparative fit index, and the Tucker-Lewis index) and their standard cutoff values to detect the optimal number of latent dimensions underlying sets of dichotomous items. Models were fit to data generated from three-factor population structures that varied in factor loading magnitude, factor intercorrelation magnitude, number of indicators, and whether cross loadings or minor factors were included. The effectiveness of the thresholds varied across fit statistics, and was conditional on many features of the underlying model. Together, results suggest that conventional fit thresholds offer questionable utility in the context of IFA.

  3. Types of suggestibility: Relationships among compliance, indirect, and direct suggestibility.

    Science.gov (United States)

    Polczyk, Romuald; Pasek, Tomasz

    2006-10-01

    It is commonly believed that direct suggestibility, referring to overt influence, and indirect suggestibility, in which the intention to influence is hidden, correlate poorly. This study demonstrates that they are substantially related, provided that they tap similar areas of influence. Test results from 103 students, 55 women and 48 men, were entered into regression analyses. Indirect suggestibility, as measured by the Sensory Suggestibility Scale for Groups, and compliance, measured by the Gudjonsson Compliance Scale, were predictors of direct suggestibility, assessed with the Barber Suggestibility Scale. Spectral analyses showed that indirect suggestibility is more related to difficult tasks on the BSS, but compliance is more related to easy tasks on this scale.

  4. Parallelized preconditioned model building algorithm for matrix factorization

    OpenAIRE

    Kaya, Kamer; Birbil, İlker; Birbil, Ilker; Öztürk, Mehmet Kaan; Ozturk, Mehmet Kaan; Gohari, Amir

    2017-01-01

    Matrix factorization is a common task underlying several machine learning applications such as recommender systems, topic modeling, or compressed sensing. Given a large and possibly sparse matrix A, we seek two smaller matrices W and H such that their product is as close to A as possible. The objective is minimizing the sum of square errors in the approximation. Typically such problems involve hundreds of thousands of unknowns, so an optimizer must be exceptionally efficient. In this study, a...

  5. Suggested improvements to the definitions of Standardized Plant Analysis of Risk-Human Reliability Analysis (SPAR-H) performance shaping factors, their levels and multipliers and the nominal tasks

    International Nuclear Information System (INIS)

    Laumann, Karin; Rasmussen, Martin

    2016-01-01

    This paper discusses the definitions and content of eight performance shaping factors (PSFs) used in Standardized Plant Analysis of Risk-Human Reliability Analysis (SPAR-H) and their levels and multipliers. Definitions of nominal tasks are also discussed. The discussion is based on a review of literature on PSFs, interviews with consultants who have carried out SPAR-H analysis in the petroleum industry and an evaluation of human reliability analysis reports based on SPAR-H analysis. We concluded that SPAR-H definitions and descriptions of the PSFs are unclear and overlap too much, making it difficult for the analyst to choose between them and select the appropriate level. This reduces inter-rater reliability and thus the consistency of SPAR-H analyses. New definitions of the PSFs, levels and multipliers are suggested with the aim to develop more specific definitions of the PSFs in order to increase the inter-rater reliability of SPAR-H. Another aim was to construct more varied and more nuanced levels and multipliers to improve the capacity of SPAR-H analysis to capture the degree of difficulty faced by operators in different scenarios. We also suggest that only one of two nominal SPAR-H tasks should be retained owing to the difficulty in distinguishing between them. - Highlights: • The SPAR-H guidelines should be revised. • Descriptions of the PSFs should be improved. • New definitions should reduce overlap between the PSFs. • The multipliers are based on an “old” method and should be revised. • Some PSF levels and multipliers in SPAR-H are not logical.

  6. INNOVATIVE PRACTICES IN TOURISM. APOSSIBLE MODEL BY FOSTERING SHADOW FACTORS

    Directory of Open Access Journals (Sweden)

    Ada Mirela TOMESCU

    2015-08-01

    Full Text Available The paper is the result of an empirical research, a study that includes a theoretical framework. The data used to test our hypotheses come from 60 small tourism firms from Bihor County, Romania. The research conducted has revealed that actions focusing on innovation must be based on a solid analysis, supported by the knowledge and the understanding of the contextual factors (environment, culture as a mental programming, values also based on the organizational factors (the management commitment, systemic perspective, learning and practice of experimentation, rapid transfer of knowledge within the organization. For the purpose of this work, the contextual factors that are exogenous represent the shadow factors. The studies performed in three European projects implemented in tourism SMEs of Bihor County have allowed us to advance the idea that contextual and organizational factors, that are identified as the source of innovation are based on rationality, which is enlarged by affectivity and imagination. The identified correlations may be considered, in our opinion an element of novelty and originality. Finally, the purpose of this paper is to provide a possible model, based on the idea of building an innovative firm, the one that has learned how to determine their own employees to be innovative. O03, L2, L26

  7. Factor structure of a conceptual model of oral health tested among 65-year olds in Norway and Sweden.

    Science.gov (United States)

    Astrøm, Anne Nordrehaug; Ekbäck, Gunnar; Ordell, Sven

    2010-04-01

    , suggesting that the 3-factor model is comparable to some extent across 65-year olds in Norway and Sweden.

  8. Modeling soft factors in computer-based wargames

    Science.gov (United States)

    Alexander, Steven M.; Ross, David O.; Vinarskai, Jonathan S.; Farr, Steven D.

    2002-07-01

    Computer-based wargames have seen much improvement in recent years due to rapid increases in computing power. Because these games have been developed for the entertainment industry, most of these advances have centered on the graphics, sound, and user interfaces integrated into these wargames with less attention paid to the game's fidelity. However, for a wargame to be useful to the military, it must closely approximate as many of the elements of war as possible. Among the elements that are typically not modeled or are poorly modeled in nearly all military computer-based wargames are systematic effects, command and control, intelligence, morale, training, and other human and political factors. These aspects of war, with the possible exception of systematic effects, are individually modeled quite well in many board-based commercial wargames. The work described in this paper focuses on incorporating these elements from the board-based games into a computer-based wargame. This paper will also address the modeling and simulation of the systemic paralysis of an adversary that is implied by the concept of Effects Based Operations (EBO). Combining the fidelity of current commercial board wargames with the speed, ease of use, and advanced visualization of the computer can significantly improve the effectiveness of military decision making and education. Once in place, the process of converting board wargames concepts to computer wargames will allow the infusion of soft factors into military training and planning.

  9. Analyzing Factors Influencing Teaching as a Career Choice Using Structural Equation Modeling

    Directory of Open Access Journals (Sweden)

    Budhinath Padhy

    2015-02-01

    Full Text Available The purpose of the study is to analyze factors influencing students’ perceptions of teaching as a career choice using structural equation modeling with the goal of shaping a teacher education recruitment program. In this study, 458 students from a Midwestern university in the United States responded to an online survey about career-related factors they value, their expectation that teaching would offer those factors, and any social-influence factors that might encourage them to choose a teaching career. The effect of 10 exogenous motivation variables (value-environment, value-intrinsic, value-extrinsic, value-altruistic, expectancy-environment, expectancy-intrinsic, expectancy-extrinsic, social-media-education, social-prior-experience, and social-suggestions on choosing a teaching career was examined. Results of our analysis showed that the factors related to expectancy-environment, expectancy-intrinsic, social-media-education, social-prior-experience, and social-suggestions were found to be significant, whereas value-related factors and expectancy-extrinsic factors were found to be insignificant.

  10. Interpersonal success factors for strategy implementation: a case study using group model building

    OpenAIRE

    Rodney J Scott; Robert Y Cavana; Donald Cameron

    2015-01-01

    Strategy implementation has been identified as an area of system dynamics literature requiring greater attention. Most strategies fail to be implemented successfully, and processes for effectively implementing strategy are yet to be fully explained and explored. The reported interpersonal success factors for strategy implementation are reported outcomes for group model building, suggesting potential applicability. A case study using validated survey methods yielded promising results, and sugg...

  11. MODELING POLLINATION FACTORS THAT INFLUENCE ALFALFA SEED YIELD IN NORTH-CENTRAL NEVADA

    OpenAIRE

    BREAZEALE, Don; FERNANDEZ, George; NARAYANAN, Rangesan

    2008-01-01

    The relative importance of both environmental and management factors on alfalfa seed yield was investigated on North–Central Nevada farms. Multiple linear regression models using 2002-2003 data revealed that cumulative tripped fl owers increased seed yield in both years. Field location does not appear to make a difference in the observed variation in tripped fl ower production. The results suggest that seed yield can be increased by (a) by placing bee shelters closer and (b) cultural practice...

  12. Suggestibility and suggestive modulation of the Stroop effect.

    Science.gov (United States)

    Kirsch, Irving

    2011-06-01

    Although the induction of a hypnotic state does not seem necessary for suggestive modulation of the Stroop effect, this important phenomenon has seemed to be dependent on the subject's level of hypnotic suggestibility. Raz and Campbell's (2011) study indicates that suggestion can modulate the Stroop effect substantially in very low suggestible subjects, as well as in those who are highly suggestible. This finding casts doubt on the presumed mechanism by which suggestive modulation is brought about. Research aimed at uncovering the means by which low suggestible individuals are able to modulate the Stroop effect would be welcome, as would assessment of this effect in moderately suggestible people. Copyright © 2010 Elsevier Inc. All rights reserved.

  13. Modeling of human factor Va inactivation by activated protein C

    Directory of Open Access Journals (Sweden)

    Bravo Maria

    2012-05-01

    Full Text Available Abstract Background Because understanding of the inventory, connectivity and dynamics of the components characterizing the process of coagulation is relatively mature, it has become an attractive target for physiochemical modeling. Such models can potentially improve the design of therapeutics. The prothrombinase complex (composed of the protease factor (FXa and its cofactor FVa plays a central role in this network as the main producer of thrombin, which catalyses both the activation of platelets and the conversion of fibrinogen to fibrin, the main substances of a clot. A key negative feedback loop that prevents clot propagation beyond the site of injury is the thrombin-dependent generation of activated protein C (APC, an enzyme that inactivates FVa, thus neutralizing the prothrombinase complex. APC inactivation of FVa is complex, involving the production of partially active intermediates and “protection” of FVa from APC by both FXa and prothrombin. An empirically validated mathematical model of this process would be useful in advancing the predictive capacity of comprehensive models of coagulation. Results A model of human APC inactivation of prothrombinase was constructed in a stepwise fashion by analyzing time courses of FVa inactivation in empirical reaction systems with increasing number of interacting components and generating corresponding model constructs of each reaction system. Reaction mechanisms, rate constants and equilibrium constants informing these model constructs were initially derived from various research groups reporting on APC inactivation of FVa in isolation, or in the presence of FXa or prothrombin. Model predictions were assessed against empirical data measuring the appearance and disappearance of multiple FVa degradation intermediates as well as prothrombinase activity changes, with plasma proteins derived from multiple preparations. Our work integrates previously published findings and through the cooperative

  14. Computer modeling the boron compound factor in normal brain tissue

    International Nuclear Information System (INIS)

    Gavin, P.R.; Huiskamp, R.; Wheeler, F.J.; Griebenow, M.L.

    1993-01-01

    The macroscopic distribution of borocaptate sodium (Na 2 B 12 H 11 SH or BSH) in normal tissues has been determined and can be accurately predicted from the blood concentration. The compound para-borono-phenylalanine (p-BPA) has also been studied in dogs and normal tissue distribution has been determined. The total physical dose required to reach a biological isoeffect appears to increase directly as the proportion of boron capture dose increases. This effect, together with knowledge of the macrodistribution, led to estimates of the influence of the microdistribution of the BSH compound. This paper reports a computer model that was used to predict the compound factor for BSH and p-BPA and, hence, the equivalent radiation in normal tissues. The compound factor would need to be calculated for other compounds with different distributions. This information is needed to design appropriate normal tissue tolerance studies for different organ systems and/or different boron compounds

  15. Positive Orientation and the Five-Factor Model

    Directory of Open Access Journals (Sweden)

    Miciuk Łukasz Roland

    2016-04-01

    Full Text Available The aim of the present study was to investigate the relationship between positive orientation (PO defined as a basic predisposition to perceive and evaluate positive aspects of life, the future and oneself and the Five-Factor Model of personality (FFM. Hypotheses postulated positive correlations between PO and extraversion, conscientiousness, agreeableness and openness; a negative correlation was predicted between PO and neuroticism. Two hundred Polish students completed the following measures: SES (Self-Esteem Scale, Rosenberg, SWLS (The Satisfaction with Life Scale; Diener, Emmons, Larson & Griffin, LOT-R (The Life Orientation Test - Revised; Scheier, Carver & Bridges and NEOFFI (NEO Five Factor Inventory, Costa & McCrae. The results confirmed correlations between PO and extraversion, conscientiousness, and neuroticism; correlations with openness and agreeableness were not supported. According to canonical correlations, PO shows a clear affinity to the FFM.

  16. Workforce scheduling: A new model incorporating human factors

    Directory of Open Access Journals (Sweden)

    Mohammed Othman

    2012-12-01

    Full Text Available Purpose: The majority of a company’s improvement comes when the right workers with the right skills, behaviors and capacities are deployed appropriately throughout a company. This paper considers a workforce scheduling model including human aspects such as skills, training, workers’ personalities, workers’ breaks and workers’ fatigue and recovery levels. This model helps to minimize the hiring, firing, training and overtime costs, minimize the number of fired workers with high performance, minimize the break time and minimize the average worker’s fatigue level.Design/methodology/approach: To achieve this objective, a multi objective mixed integer programming model is developed to determine the amount of hiring, firing, training and overtime for each worker type.Findings: The results indicate that the worker differences should be considered in workforce scheduling to generate realistic plans with minimum costs. This paper also investigates the effects of human fatigue and recovery on the performance of the production systems.Research limitations/implications: In this research, there are some assumptions that might affect the accuracy of the model such as the assumption of certainty of the demand in each period, and the linearity function of Fatigue accumulation and recovery curves. These assumptions can be relaxed in future work.Originality/value: In this research, a new model for integrating workers’ differences with workforce scheduling is proposed. To the authors' knowledge, it is the first time to study the effects of different important human factors such as human personality, skills and fatigue and recovery in the workforce scheduling process. This research shows that considering both technical and human factors together can reduce the costs in manufacturing systems and ensure the safety of the workers.

  17. Modeling Shear Induced Von Willebrand Factor Binding to Collagen

    Science.gov (United States)

    Dong, Chuqiao; Wei, Wei; Morabito, Michael; Webb, Edmund; Oztekin, Alparslan; Zhang, Xiaohui; Cheng, Xuanhong

    2017-11-01

    Von Willebrand factor (vWF) is a blood glycoprotein that binds with platelets and collagen on injured vessel surfaces to form clots. VWF bioactivity is shear flow induced: at low shear, binding between VWF and other biological entities is suppressed; for high shear rate conditions - as are found near arterial injury sites - VWF elongates, activating its binding with platelets and collagen. Based on parameters derived from single molecule force spectroscopy experiments, we developed a coarse-grain molecular model to simulate bond formation probability as a function of shear rate. By introducing a binding criterion that depends on the conformation of a sub-monomer molecular feature of our model, the model predicts shear-induced binding, even for conditions where binding is highly energetically favorable. We further investigate the influence of various model parameters on the ability to predict shear-induced binding (vWF length, collagen site density and distribution, binding energy landscape, and slip/catch bond length) and demonstrate parameter ranges where the model provides good agreement with existing experimental data. Our results may be important for understanding vWF activity and also for achieving targeted drug therapy via biomimetic synthetic molecules. National Science Foundation (NSF),Division of Mathematical Sciences (DMS).

  18. Assessment of the five-factor model of personality.

    Science.gov (United States)

    Widiger, T A; Trull, T J

    1997-04-01

    The five-factor model (FFM) of personality is obtaining construct validation, recognition, and practical consideration across a broad domain of fields, including clinical psychology, industrial-organizational psychology, and health psychology. As a result, an array of instruments have been developed and existing instruments are being modified to assess the FFM. In this article, we present an overview and critique of five such instruments (the Goldberg Big Five Markers, the revised NEO Personality Inventory, the Interpersonal Adjective Scales-Big Five, the Personality Psychopathology-Five, and the Hogan Personality Inventory), focusing in particular on their representation of the lexical FFM and their practical application.

  19. Replica Analysis for Portfolio Optimization with Single-Factor Model

    Science.gov (United States)

    Shinzato, Takashi

    2017-06-01

    In this paper, we use replica analysis to investigate the influence of correlation among the return rates of assets on the solution of the portfolio optimization problem. We consider the behavior of an optimal solution for the case where the return rate is described with a single-factor model and compare the findings obtained from our proposed methods with correlated return rates with those obtained with independent return rates. We then analytically assess the increase in the investment risk when correlation is included. Furthermore, we also compare our approach with analytical procedures for minimizing the investment risk from operations research.

  20. Liberal bias and the five-factor model.

    Science.gov (United States)

    Charney, Evan

    2015-01-01

    Duarte et al. draw attention to the "embedding of liberal values and methods" in social psychological research. They note how these biases are often invisible to the researchers themselves. The authors themselves fall prey to these "invisible biases" by utilizing the five-factor model of personality and the trait of openness to experience as one possible explanation for the under-representation of political conservatives in social psychology. I show that the manner in which the trait of openness to experience is conceptualized and measured is a particularly blatant example of the very liberal bias the authors decry.

  1. Human Factors Engineering Review Model for advanced nuclear power reactors

    International Nuclear Information System (INIS)

    O'Hara, J.; Higgins, J.; Goodman, C.; Galletti, G.: Eckenrode, R.

    1993-01-01

    One of the major issues to emerge from the initial design reviews under the certification process was that detailed human-systems interface (HSI) design information was not available for staff review. To address the lack of design detail issue. The Nuclear Regulatory Commission (NRC) is performing the design certification reviews based on a design process plan which describes the human factors engineering (HFE) program elements that are necessary and sufficient to develop an acceptable detailed design specification. Since the review of a design process is unprecedented in the nuclear industry. The criteria for review are not addressed by current regulations or guidance documents and. therefore, had to be developed. Thus, an HFE Program Review Model was developed. This paper will describe the model's rationale, scope, objectives, development, general characteristics. and application

  2. How Do Various Maize Crop Models Vary in Their Responses to Climate Change Factors?

    Science.gov (United States)

    Bassu, Simona; Brisson, Nadine; Grassini, Patricio; Durand, Jean-Louis; Boote, Kenneth; Lizaso, Jon; Jones, James W.; Rosenzweig, Cynthia; Ruane, Alex C.; Adam, Myriam; hide

    2014-01-01

    Potential consequences of climate change on crop production can be studied using mechanistic crop simulation models. While a broad variety of maize simulation models exist, it is not known whether different models diverge on grain yield responses to changes in climatic factors, or whether they agree in their general trends related to phenology, growth, and yield. With the goal of analyzing the sensitivity of simulated yields to changes in temperature and atmospheric carbon dioxide concentrations [CO2], we present the largest maize crop model intercomparison to date, including 23 different models. These models were evaluated for four locations representing a wide range of maize production conditions in the world: Lusignan (France), Ames (USA), Rio Verde (Brazil) and Morogoro (Tanzania). While individual models differed considerably in absolute yield simulation at the four sites, an ensemble of a minimum number of models was able to simulate absolute yields accurately at the four sites even with low data for calibration, thus suggesting that using an ensemble of models has merit. Temperature increase had strong negative influence on modeled yield response of roughly -0.5 Mg ha(sup 1) per degC. Doubling [CO2] from 360 to 720 lmol mol 1 increased grain yield by 7.5% on average across models and the sites. That would therefore make temperature the main factor altering maize yields at the end of this century. Furthermore, there was a large uncertainty in the yield response to [CO2] among models. Model responses to temperature and [CO2] did not differ whether models were simulated with low calibration information or, simulated with high level of calibration information.

  3. A survey of the influencing factors and models for resident's household waste management behavior

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The problem of household solid waste has been concerned and researched on by municipalities and researchers.At present, household solid waste has been changed to management problem from technical one. From the point view of management, the research on household solid waste is to study the factors which influence resident's behavior of managtng their waste. Based on the literature review, firstly, this paper summarizes those factors which have already been identified to have impact on resident's behavior of managing their waste. They are social-demographic variables,knowledge, environmental values, psychological factors, publicity and system design. Secondly, three typical models of the relationship between factors and behavior, which are factors determining task performance in waste management,conceptualization of waste management behavior and the theoretical model of repeated behavior on household waste management, are analyzed and the deficiencies of these models are also analyzed. Finally, according to the current situation in household waste management and the culture and resident's habits in China, this paper puts forward a research focus and suggestions about resident 's behavior of household solid waste management.

  4. Influencing Factors and Simplified Model of Film Hole Irrigation

    Directory of Open Access Journals (Sweden)

    Yi-Bo Li

    2017-07-01

    Full Text Available Film hole irrigation is an advanced low-cost and high-efficiency irrigation method, which can improve water conservation and water use efficiency. Given its various advantages and potential applications, we conducted a laboratory study to investigate the effects of soil texture, bulk density, initial soil moisture, irrigation depth, opening ratio (ρ, film hole diameter (D, and spacing on cumulative infiltration using SWMS-2D. We then proposed a simplified model based on the Kostiakov model for infiltration estimation. Error analyses indicated SWMS-2D to be suitable for infiltration simulation of film hole irrigation. Additional SWMS-2D-based investigations indicated that, for a certain soil, initial soil moisture and irrigation depth had the weakest effects on cumulative infiltration, whereas ρ and D had the strongest effects on cumulative infiltration. A simplified model with ρ and D was further established, and its use was then expanded to different soils. Verification based on seven soil types indicated that the established simplified double-factor model effectively estimates cumulative infiltration for film hole irrigation, with a small mean average error of 0.141–2.299 mm, a root mean square error of 0.177–2.722 mm, a percent bias of −2.131–1.479%, and a large Nash–Sutcliffe coefficient that is close to 1.0.

  5. Talent identification model for sprinter using discriminant factor

    Science.gov (United States)

    Kusnanik, N. W.; Hariyanto, A.; Herdyanto, Y.; Satia, A.

    2018-01-01

    The main purpose of this study was to identify young talented sprinter using discriminant factor. The research was conducted in 3 steps including item pool, screening of item pool, and trial of instruments at the small and big size of samples. 315 male elementary school students participated in this study with mean age of 11-13 years old. Data were collected by measuring anthropometry (standing height, sitting height, body mass, and leg length); testing physical fitness (40m sprint for speed, shuttle run for agility, standing broad jump for power, multistage fitness test for endurance). Data were analyzed using discriminant factor. The result of this study found that there were 5 items that selected as an instrument to identify young talented sprinter: sitting height, body mass, leg length, sprint 40m, and multistage fitness test. Model of Discriminant for talent identification in sprinter was D = -24,497 + (0,155 sitting height) + (0,080 body mass) + (0,148 leg length) + (-1,225 Sprint 40m) + (0,563 MFT). The conclusion of this study: instrument tests that have been selected and discriminant model that have been found can be applied to identify young talented as a sprinter.

  6. Deepening Sleep by Hypnotic Suggestion

    Science.gov (United States)

    Cordi, Maren J.; Schlarb, Angelika A.; Rasch, Björn

    2014-01-01

    Study Objectives: Slow wave sleep (SWS) plays a critical role in body restoration and promotes brain plasticity; however, it markedly declines across the lifespan. Despite its importance, effective tools to increase SWS are rare. Here we tested whether a hypnotic suggestion to “sleep deeper” extends the amount of SWS. Design: Within-subject, placebo-controlled crossover design. Setting: Sleep laboratory at the University of Zurich, Switzerland. Participants: Seventy healthy females 23.27 ± 3.17 y. Intervention: Participants listened to an auditory text with hypnotic suggestions or a control tape before napping for 90 min while high-density electroencephalography was recorded. Measurements and Results: After participants listened to the hypnotic suggestion to “sleep deeper” subsequent SWS was increased by 81% and time spent awake was reduced by 67% (with the amount of SWS or wake in the control condition set to 100%). Other sleep stages remained unaffected. Additionally, slow wave activity was significantly enhanced after hypnotic suggestions. During the hypnotic tape, parietal theta power increases predicted the hypnosis-induced extension of SWS. Additional experiments confirmed that the beneficial effect of hypnotic suggestions on SWS was specific to the hypnotic suggestion and did not occur in low suggestible participants. Conclusions: Our results demonstrate the effectiveness of hypnotic suggestions to specifically increase the amount and duration of slow wave sleep (SWS) in a midday nap using objective measures of sleep in young, healthy, suggestible females. Hypnotic suggestions might be a successful tool with a lower risk of adverse side effects than pharmacological treatments to extend SWS also in clinical and elderly populations. Citation: Cordi MJ, Schlarb AA, Rasch B. Deepening sleep by hypnotic suggestion. SLEEP 2014;37(6):1143-1152. PMID:24882909

  7. Dimensional models of personality: the five-factor model and the DSM-5

    Science.gov (United States)

    Trull, Timothy J.; Widiger, Thomas A.

    2013-01-01

    It is evident that the classification of personality disorder is shifting toward a dimensional trait model and, more specifically, the five-factor model (FFM). The purpose of this paper is to provide an overview of the FFM of personality disorder. It will begin with a description of this dimensional model of normal and abnormal personality functioning, followed by a comparison with a proposal for future revisions to DSM-5 and a discussion of its potential advantages as an integrative hierarchical model of normal and abnormal personality structure. PMID:24174888

  8. Granularity as a Cognitive Factor in the Effectiveness of Business Process Model Reuse

    Science.gov (United States)

    Holschke, Oliver; Rake, Jannis; Levina, Olga

    Reusing design models is an attractive approach in business process modeling as modeling efficiency and quality of design outcomes may be significantly improved. However, reusing conceptual models is not a cost-free effort, but has to be carefully designed. While factors such as psychological anchoring and task-adequacy in reuse-based modeling tasks have been investigated, information granularity as a cognitive concept has not been at the center of empirical research yet. We hypothesize that business process granularity as a factor in design tasks under reuse has a significant impact on the effectiveness of resulting business process models. We test our hypothesis in a comparative study employing high and low granularities. The reusable processes provided were taken from widely accessible reference models for the telecommunication industry (enhanced Telecom Operations Map). First experimental results show that Recall in tasks involving coarser granularity is lower than in cases of finer granularity. These findings suggest that decision makers in business process management should be considerate with regard to the implementation of reuse mechanisms of different granularities. We realize that due to our small sample size results are not statistically significant, but this preliminary run shows that it is ready for running on a larger scale.

  9. [Risk factors of eating disorders in the narratives of fashion models].

    Science.gov (United States)

    Bogár, Nikolett; Túry, Ferenc

    2017-01-01

    The risk of eating disorders is high in populations who are exposed to slimness ideal, so among fashion models. The present qualitative study evaluates the risk factors of eating disorders in a group of fashion models with semistructured interview. Moreover, the aim of the study was to examine the impact of professional requirements on the health of models. The study group was internationally heterogeneous. The models were involved by personal professional relationship. A semistructured questionnaire was used by e-mail containing anthropometric data and different aspects of the model profession. 29 female and three male models, three agents, two designers, three fotographers, one personal trainer and one stylist answered the questionnaire. Transient bulimic symptoms were reported by six female models (21%). Moreover, five female models fulfilled the DSM-5 criteria of anorexia nervosa or bulimia nervosa. Four of them were anorexic (body mass index: 13.9-15.3), one was bulimic. The symptoms of three persons began before the model career, those of two models after it. 17 models reported that the model profession intensively increased the bodily preoccupations. The study corroborates the effect of the model profession on the increase of the risk for eating disorders. In the case of the models, whose eating disorder began after stepping into the model profession, the role of the representants of the fashion industry can be suggested as a form of psychological abuse. As the models or in the case of underages their parents accepted the strong requirement of slimness, an unconscious collusion is probable. Our date highlight the health impact of cultural ideals, and call the attention to prevention strategies.

  10. Modeling the assessment of the economic factors impact on the development of social entrepreneurship

    Science.gov (United States)

    Absalyamov, T.; Kundakchyan, R.; Zulfakarova, L.; Zapparova, Z.

    2017-12-01

    The article deals with the research of modern trends in the development of social entrepreneurship in Russia. The results of the research allow the authors to identify a system of factors that affect the development of entrepreneurship in the modern Russian economy. Moreover, the authors argue the regional specificity of the development of social entrepreneurship. The paper considers specific features and formulates the main limitations of the development of entrepreneurship and the competitive environment in the social sphere. The authors suggest an econometric model for assessing the influence of economic factors on the development of socially-oriented entrepreneurship and present an algorithm for calculating its components. The results of the econometric analysis identify the main factors of the change in the performance indicators of entrepreneurial activity and determine the degree of their impact on social entrepreneurship. The results and conclusions can serve as an estimation of the socioeconomic consequences of the sustainability disruption of the entrepreneurial potential realization in the social sphere.

  11. Zero-Inflated Poisson Modeling of Fall Risk Factors in Community-Dwelling Older Adults.

    Science.gov (United States)

    Jung, Dukyoo; Kang, Younhee; Kim, Mi Young; Ma, Rye-Won; Bhandari, Pratibha

    2016-02-01

    The aim of this study was to identify risk factors for falls among community-dwelling older adults. The study used a cross-sectional descriptive design. Self-report questionnaires were used to collect data from 658 community-dwelling older adults and were analyzed using logistic and zero-inflated Poisson (ZIP) regression. Perceived health status was a significant factor in the count model, and fall efficacy emerged as a significant predictor in the logistic models. The findings suggest that fall efficacy is important for predicting not only faller and nonfaller status but also fall counts in older adults who may or may not have experienced a previous fall. The fall predictors identified in this study--perceived health status and fall efficacy--indicate the need for fall-prevention programs tailored to address both the physical and psychological issues unique to older adults. © The Author(s) 2014.

  12. An extended technology acceptance model for detecting influencing factors: An empirical investigation

    Directory of Open Access Journals (Sweden)

    Mohamd Hakkak

    2013-11-01

    Full Text Available The rapid diffusion of the Internet has radically changed the delivery channels applied by the financial services industry. The aim of this study is to identify the influencing factors that encourage customers to adopt online banking in Khorramabad. The research constructs are developed based on the technology acceptance model (TAM and incorporates some extra important control variables. The model is empirically verified to study the factors influencing the online banking adoption behavior of 210 customers of Tejarat Banks in Khorramabad. The findings of the study suggest that the quality of the internet connection, the awareness of online banking and its benefits, the social influence and computer self-efficacy have significant impacts on the perceived usefulness (PU and perceived ease of use (PEOU of online banking acceptance. Trust and resistance to change also have significant impact on the attitude towards the likelihood of adopting online banking.

  13. Use of model plant hosts to identify Pseudomonas aeruginosa virulence factors

    Science.gov (United States)

    Rahme, Laurence G.; Tan, Man-Wah; Le, Long; Wong, Sandy M.; Tompkins, Ronald G.; Calderwood, Stephen B.; Ausubel, Frederick M.

    1997-01-01

    We used plants as an in vivo pathogenesis model for the identification of virulence factors of the human opportunistic pathogen Pseudomonas aeruginosa. Nine of nine TnphoA mutant derivatives of P. aeruginosa strain UCBPP-PA14 that were identified in a plant leaf assay for less pathogenic mutants also exhibited significantly reduced pathogenicity in a burned mouse pathogenicity model, suggesting that P. aeruginosa utilizes common strategies to infect both hosts. Seven of these nine mutants contain TnphoA insertions in previously unknown genes. These results demonstrate that an alternative nonvertebrate host of a human bacterial pathogen can be used in an in vivo high throughput screen to identify novel bacterial virulence factors involved in mammalian pathogenesis. PMID:9371831

  14. Motivation Factors for Adopting Building Information Modeling (BIM in Iraq

    Directory of Open Access Journals (Sweden)

    W. A. Hatem

    2018-04-01

    Full Text Available Building information modeling (BIM is an integrated and comprehensive system including whatever is related to a construction project and its stages. It represents a unified database for all project data through which project documents are available to all stakeholders. This paper evaluates the factors driving the adoption of BIM in Iraqi construction projects in different ministries and adopts quantitative approach to collect data by using a questionnaire survey specially prepared for this purpose which was distributed to experts in the ministries of the Iraqi construction sector. Returned data were subjected to proper statistical analysis. Results showed that the highest motivation for BIM application is to include it in the educational curricula, raise awareness through courses and workshops and contracting with international experts with experience in BIM field.

  15. Latent Fundamentals Arbitrage with a Mixed Effects Factor Model

    Directory of Open Access Journals (Sweden)

    Andrei Salem Gonçalves

    2012-09-01

    Full Text Available We propose a single-factor mixed effects panel data model to create an arbitrage portfolio that identifies differences in firm-level latent fundamentals. Furthermore, we show that even though the characteristics that affect returns are unknown variables, it is possible to identify the strength of the combination of these latent fundamentals for each stock by following a simple approach using historical data. As a result, a trading strategy that bought the stocks with the best fundamentals (strong fundamentals portfolio and sold the stocks with the worst ones (weak fundamentals portfolio realized significant risk-adjusted returns in the U.S. market for the period between July 1986 and June 2008. To ensure robustness, we performed sub period and seasonal analyses and adjusted for trading costs and we found further empirical evidence that using a simple investment rule, that identified these latent fundamentals from the structure of past returns, can lead to profit.

  16. Modeling Structural, Dyadic, and Individual Factors: The Inclusion and Exclusion Model of HIV Related Behavior

    OpenAIRE

    Albarracin, Dolores; Tannenbaum, Melanie B.; Glasman, Laura R.; Rothman, Alexander J.

    2010-01-01

    Changing HIV-related behaviors requires addressing the individual, dyadic, and structural influences that shape them. This supplement of AIDS & Behavior presents frameworks that integrate these three influences on behavior. Concepts from these frameworks were selected to model the processes by which structural factors affect individual HIV-related behavior. In the Inclusion/Exclusion Model, material and symbolic inclusions and exclusions (sharing versus denying resources) regulate individuals...

  17. mathematical models for prediction of safety factors for a simply

    African Journals Online (AJOL)

    HOD

    Keywords: reliability, code calibration, load factor, safety factor, design, steel beam. 1. INTRODUCTION ... safety factors for the design of a simply supported steel beam using regression .... 5 design criteria for a solid timber portal frame.

  18. Five-Factor Model personality profiles of drug users

    Directory of Open Access Journals (Sweden)

    Crum Rosa M

    2008-04-01

    Full Text Available Abstract Background Personality traits are considered risk factors for drug use, and, in turn, the psychoactive substances impact individuals' traits. Furthermore, there is increasing interest in developing treatment approaches that match an individual's personality profile. To advance our knowledge of the role of individual differences in drug use, the present study compares the personality profile of tobacco, marijuana, cocaine, and heroin users and non-users using the wide spectrum Five-Factor Model (FFM of personality in a diverse community sample. Method Participants (N = 1,102; mean age = 57 were part of the Epidemiologic Catchment Area (ECA program in Baltimore, MD, USA. The sample was drawn from a community with a wide range of socio-economic conditions. Personality traits were assessed with the Revised NEO Personality Inventory (NEO-PI-R, and psychoactive substance use was assessed with systematic interview. Results Compared to never smokers, current cigarette smokers score lower on Conscientiousness and higher on Neuroticism. Similar, but more extreme, is the profile of cocaine/heroin users, which score very high on Neuroticism, especially Vulnerability, and very low on Conscientiousness, particularly Competence, Achievement-Striving, and Deliberation. By contrast, marijuana users score high on Openness to Experience, average on Neuroticism, but low on Agreeableness and Conscientiousness. Conclusion In addition to confirming high levels of negative affect and impulsive traits, this study highlights the links between drug use and low Conscientiousness. These links provide insight into the etiology of drug use and have implications for public health interventions.

  19. The pion form factor within the hidden local symmetry model

    International Nuclear Information System (INIS)

    Benayoun, M.; David, P.; DelBuono, L.; Leruste, P.; O'Connell, H.B.

    2003-01-01

    We analyze a pion form factor formulation which fulfills the Analyticity requirement within the Hidden Local Symmetry (HLS) Model. This implies an s-dependent dressing of the ρ-γ VMD coupling and an account of several coupled channels. The corresponding function F π (s) provides nice fits of the pion form factor data from s=-0.25 to s=1 GeV 2 . It is shown that the coupling to KK has little effect, while ωπ 0 improves significantly the fit probability below the φ mass. No need for additional states like ρ(1450) shows up in this invariant-mass range. All parameters, except for the subtraction polynomial coefficients, are fixed from the rest of the HLS phenomenology. The fits show consistency with the expected behaviour of F π (s) at s=0 up to O(s 2 ) and with the phase shift data on δ 1 1 (s) from threshold to somewhat above the φ mass. The ω sector is also examined in relation with recent data from CMD-2. (orig.)

  20. Logistic regression for risk factor modelling in stuttering research.

    Science.gov (United States)

    Reed, Phil; Wu, Yaqionq

    2013-06-01

    To outline the uses of logistic regression and other statistical methods for risk factor analysis in the context of research on stuttering. The principles underlying the application of a logistic regression are illustrated, and the types of questions to which such a technique has been applied in the stuttering field are outlined. The assumptions and limitations of the technique are discussed with respect to existing stuttering research, and with respect to formulating appropriate research strategies to accommodate these considerations. Finally, some alternatives to the approach are briefly discussed. The way the statistical procedures are employed are demonstrated with some hypothetical data. Research into several practical issues concerning stuttering could benefit if risk factor modelling were used. Important examples are early diagnosis, prognosis (whether a child will recover or persist) and assessment of treatment outcome. After reading this article you will: (a) Summarize the situations in which logistic regression can be applied to a range of issues about stuttering; (b) Follow the steps in performing a logistic regression analysis; (c) Describe the assumptions of the logistic regression technique and the precautions that need to be checked when it is employed; (d) Be able to summarize its advantages over other techniques like estimation of group differences and simple regression. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Representational constraints on children's suggestibility.

    Science.gov (United States)

    Ceci, Stephen J; Papierno, Paul B; Kulkofsky, Sarah

    2007-06-01

    In a multistage experiment, twelve 4- and 9-year-old children participated in a triad rating task. Their ratings were mapped with multidimensional scaling, from which euclidean distances were computed to operationalize semantic distance between items in target pairs. These children and age-mates then participated in an experiment that employed these target pairs in a story, which was followed by a misinformation manipulation. Analyses linked individual and developmental differences in suggestibility to children's representations of the target items. Semantic proximity was a strong predictor of differences in suggestibility: The closer a suggested distractor was to the original item's representation, the greater was the distractor's suggestive influence. The triad participants' semantic proximity subsequently served as the basis for correctly predicting memory performance in the larger group. Semantic proximity enabled a priori counterintuitive predictions of reverse age-related trends to be confirmed whenever the distance between representations of items in a target pair was greater for younger than for older children.

  2. A protective factors model for alcohol abuse and suicide prevention among Alaska Native youth.

    Science.gov (United States)

    Allen, James; Mohatt, Gerald V; Fok, Carlotta Ching Ting; Henry, David; Burkett, Rebekah

    2014-09-01

    This study provides an empirical test of a culturally grounded theoretical model for prevention of alcohol abuse and suicide risk with Alaska Native youth, using a promising set of culturally appropriate measures for the study of the process of change and outcome. This model is derived from qualitative work that generated an heuristic model of protective factors from alcohol (Allen et al. in J Prev Interv Commun 32:41-59, 2006; Mohatt et al. in Am J Commun Psychol 33:263-273, 2004a; Harm Reduct 1, 2004b). Participants included 413 rural Alaska Native youth ages 12-18 who assisted in testing a predictive model of Reasons for Life and Reflective Processes about alcohol abuse consequences as co-occurring outcomes. Specific individual, family, peer, and community level protective factor variables predicted these outcomes. Results suggest prominent roles for these predictor variables as intermediate prevention strategy target variables in a theoretical model for a multilevel intervention. The model guides understanding of underlying change processes in an intervention to increase the ultimate outcome variables of Reasons for Life and Reflective Processes regarding the consequences of alcohol abuse.

  3. The relationships between behavioral addictions and the five-factor model of personality.

    Science.gov (United States)

    Andreassen, Cecilie Schou; Griffiths, Mark D; Gjertsen, Siri Renate; Krossbakken, Elfrid; Kvam, Siri; Pallesen, Ståle

    2013-06-01

    Aims Although relationships between addiction and personality have previously been explored, no study has ever simultaneously investigated the interrelationships between several behavioral addictions, and related these to the main dimensions of the five-factor model of personality. Methods In this study, 218 university students completed questionnaires assessing seven different behavioral addictions (i.e., Facebook addiction, video game addiction, Internet addiction, exercise addiction, mobile phone addiction, compulsive buying, and study addiction) as well as an instrument assessing the main dimensions of the five-factor model of personality. Results Of the 21 bivariate intercorrelations between the seven behavioral addictions, all were positive (and nine significantly). The results also showed that (i) Neuroticism was positively associated with Internet addiction, exercise addiction, compulsive buying, and study addiction, (ii) Extroversion was positively associated with Facebook addiction, exercise addiction, mobile phone addiction, and compulsive buying, (iii) Openness to experience was negatively associated with Facebook addiction and mobile phone addiction, (iv) Agreeableness was negatively associated with Internet addiction, exercise addiction, mobile phone addiction, and compulsive buying, and (v) Conscientiousness was negatively associated with Facebook addiction, video game addiction, Internet addiction, and compulsive buying and positively associated with exercise addiction and study addiction. Conclusions The positive associations between the seven behavioral addictions suggest one or several underlying pathological factors. Hierarchical multiple regressions showed that personality traits explained between 6% and 17% of the variance in the seven behavioral addictions, suggesting that personality to a varying degree explains scores on measures of addictive behaviors.

  4. Some factors that will affect the next generation of forest growth models

    International Nuclear Information System (INIS)

    Leary, R.A.

    1988-01-01

    This paper discusses several types of factors that affect the form and referents of future growth models. These include philosophical, scientific, technological, educational, and organizational factors. Each factor is presented individually

  5. A comparison of the VAR model and the PC factor model in forecasting inflation in Montenegro

    Directory of Open Access Journals (Sweden)

    Lipovina-Božović Milena

    2013-01-01

    Full Text Available Montenegro started using the euro in 2002 and regained independence in 2006. Its main economic partners are European countries, yet inflation movements in Montenegro do not coincide with consumer price fluctuations in the eurozone. Trying to develop a useful forecasting model for Montenegrin inflation, we compare the results of a three-variable vector autoregression (VAR model, and a principle component (PC factor model starting with twelve variables. The estimation period is January 2001 to December 2012, and the control months are the first six months of 2013. The results show that in forecasting inflation, despite a high level of Montenegrin economic dependence on international developments, more reliable forecasts are achieved with the use of additional information on a larger number of factors, which includes domestic economic activity.

  6. Modeling the factors associating with health-related habits among Japanese students.

    Science.gov (United States)

    Mato, Mie; Tsukasaki, Keiko

    2017-11-23

    The aim of the present study was to clarify the structural relationship between health-related habits and psychosocial factors during adolescence/early adulthood. An anonymous, self-administered questionnaire was provided to 1141 third- and fourth-year students at eight academic departments from six universities in regional Japanese cities. Surveys included items addressing participants' demographic characteristics, psychosocial factors (individual-level social capital, self-efficacy, mental health (from health-related quality of life SF-36v2), and sense of coherence (SOC)), and health-related habits. A multiple indicator analysis based on structural equation modeling was conducted to examine the structural relationship between health-related habits and these factors. Valid responses were obtained from 952 participants. The final model demonstrated a high level of goodness of fit. While the path from SOC to health-related habits was significant, those from self-efficacy to health-related habits and from mental health to health-related habits were not significant. The path coefficient from SOC to health-related habits was greater than the path coefficient from background characteristics. In the multiple population comparison that considered gender, a nearly identical model was supported for men and women. Psychosocial factors related to health-related habits were social capital, self-efficacy, mental health, and SOC. Furthermore, it was suggested that SOC functions as an intervening factor for maintaining a healthy lifestyle. It was observed that individual psychosocial factors influence health-related habits more than their background characteristics. Findings highlight that supporting the building of social relationships and social environments is essential to promote a healthy lifestyle among university students. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Model-based identification and use of task complexity factors of human integrated systems

    International Nuclear Information System (INIS)

    Ham, Dong-Han; Park, Jinkyun; Jung, Wondea

    2012-01-01

    Task complexity is one of the conceptual constructs that are critical to explain and predict human performance in human integrated systems. A basic approach to evaluating the complexity of tasks is to identify task complexity factors and measure them. Although a great deal of task complexity factors have been studied, there is still a lack of conceptual frameworks for identifying and organizing them analytically, which can be generally used irrespective of the types of domains and tasks. This study proposes a model-based approach to identifying and using task complexity factors, which has two facets—the design aspects of a task and complexity dimensions. Three levels of design abstraction, which are functional, behavioral, and structural aspects of a task, characterize the design aspect of a task. The behavioral aspect is further classified into five cognitive processing activity types. The complexity dimensions explain a task complexity from different perspectives, which are size, variety, and order/organization. Twenty-one task complexity factors are identified by the combination of the attributes of each facet. Identification and evaluation of task complexity factors based on this model is believed to give insights for improving the design quality of tasks. This model for complexity factors can also be used as a referential framework for allocating tasks and designing information aids. The proposed approach is applied to procedure-based tasks of nuclear power plants (NPPs) as a case study to demonstrate its use. Last, we compare the proposed approach with other studies and then suggest some future research directions.

  8. The suggestion about the absence of the phase transition, vacuum degeneration, spontaneous symmetry breaking and zero-mass Goldstone-bosons in QFT models of the type gphi4

    International Nuclear Information System (INIS)

    Zastavenko, L.G.

    1979-01-01

    The usual proof of the phase transition existence in the gphi 4 model is considered. (For M 2 >M 0 2 minimum of the effective potential is at phi(0)=0, for M 2 >M 0 2 this minimum is at phi(0)=+-lambda not equal to 0, lambda→+ infinity at M 2 →- infinity). This proof is shown to be wrong, thus suggesting the absence in the model considered of the phase transition, vacuum degeneration, spontaneous symmetry breaking and zero-mass Goldstone-bosons

  9. A model of physical factors in the structural adaptation of microvascular networks in normotension and hypertension

    DEFF Research Database (Denmark)

    Jacobsen, Jens Christian Brings; Gustafsson, Finn; Holstein-Rathlou, N.-H.

    2003-01-01

    Adequate function of the microcirculation is vital to any tissue. To maintain an optimal function, microvascular networks must be able to adapt structurally to changes in the physical environment. Here we present a mathematical network model based on vessel wall mechanics. We assume based...... diameter, until equilibrium is restored. The model explains several of the key features observed experimentally in the microcirculation in normotension and hypertension. Most importantly, it suggests a scenario where overall network structure and network hemodynamics depend on adaptation to local...... hemodynamic stimuli in the individual vessel. Simulated results show emanating microvascular networks with properties similar to those observed in vivo. The model points to an altered endothelial function as a key factor in the development of vascular changes characteristic of hypertension....

  10. Personality-Related Problems and the Five-Factor Model of Personality

    OpenAIRE

    Boudreaux, Michael

    2014-01-01

    This research identifies a broad and inclusive set of personality-related problems and examines their empirical associations with both the high and low poles of the five-factor model of personality (FFM). McCrae, Widiger, and colleagues (e.g., McCrae, 1994; McCrae, Löckenhoff, & Costa, 2005; Widiger, Costa, & McCrae, 2002, 2012) have proposed that individuals with particular personality traits may be predisposed to particular kinds of problems in life, and suggested that the FFM serve as a ba...

  11. Norwegian mutual fund performance based on Fama and French´s five-factor model

    OpenAIRE

    Mustafa, Daniel Amir; Ali, Mohammad Yousaf

    2016-01-01

    Masteroppgave(MSc) in Master of Science in Finance - Handelshøyskolen BI, 2016 The following paper uses a dataset free of survivorship bias for the period 2002-2011. We investigate whether Norwegian mutual funds possess enough skills to outperform a passive benchmark based on Fama and French’s five-factor model. Our results suggest that the mutual fund industry exhibits significant excess returns on a 10% level in the recent financial crisis. Further, we examine whether the results obtaine...

  12. Microscopic models for hadronic form factors and vertex functions

    International Nuclear Information System (INIS)

    Santhanam, I.; Bhatnagar, S.; Mitra, A.N.

    1990-01-01

    We review the status of nucleon (N) and few-nucleon form factors (f.f.'s) from the view-point of a gradual unfolding of successively inner degrees of freedom (d.o.f.) with increase in q 2 . To this end we focus attention on the problem of a microscopic formulation of hadronic vertex functions (v.f.) from the point of view of their key role in understanding the physics of a large variety of few-hadron reactions on the one hand, and their practical usefulness in articulating the internal dynamics of hadron and few-hadron systems on the other hand. The criterion of an integrated view from low-energy spectroscopy to high-q 2 amplitudes is employed to emphasize the desirability of formulations in terms of relativistic dynamical equations based on Lorentz and gauge invariance in preference to phenomenological models, which often require additional assumptions beyond their original premises to extend their applicability domains. In this respect, the practical possibilities of the Bethe-Salpeter equation (BSE) in articulating the necessary dynamical ingredients are emphasized on a two-tier basis, the basis constants (3) being pre-determined from the mass spectral data (1 st stage) in preparation for the construction of the hadron-quark vertex functions (2 nd stage). An explicit construction is outlined for meson-quark and baryon-quark vertex functions as well as of meson-nucleon vertex functions in a stepwise fashion. The role of the latter as basic parameter-free ingredients is discussed for possible use in the more serious treatment in the current literature of quark-meson level (α) and meson-isobar (β) d.o.f. in 2-N and 3-N form factor studies. Since most of these studies are characterized by the use of RGM techniques at the six-quark level, a comparative discussion is also given of several contemporary RGM based models. Finally, the concrete prospects for employing such hardon-quark vertex functions for evaluating pp-bar annihilation amplitudes are briefly indicated

  13. Identification and synthetic modeling of factors affecting American black duck populations

    Science.gov (United States)

    Conroy, Michael J.; Miller, Mark W.; Hines, James E.

    2002-01-01

    We reviewed the literature on factors potentially affecting the population status of American black ducks (Anas rupribes). Our review suggests that there is some support for the influence of 4 major, continental-scope factors in limiting or regulating black duck populations: 1) loss in the quantity or quality of breeding habitats; 2) loss in the quantity or quality of wintering habitats; 3) harvest, and 4) interactions (competition, hybridization) with mallards (Anas platyrhychos) during the breeding and/or wintering periods. These factors were used as the basis of an annual life cycle model in which reproduction rates and survival rates were modeled as functions of the above factors, with parameters of the model describing the strength of these relationships. Variation in the model parameter values allows for consideration of scientific uncertainty as to the degree each of these factors may be contributing to declines in black duck populations, and thus allows for the investigation of the possible effects of management (e.g., habitat improvement, harvest reductions) under different assumptions. We then used available, historical data on black duck populations (abundance, annual reproduction rates, and survival rates) and possible driving factors (trends in breeding and wintering habitats, harvest rates, and abundance of mallards) to estimate model parameters. Our estimated reproduction submodel included parameters describing negative density feedback of black ducks, positive influence of breeding habitat, and negative influence of mallard densities; our survival submodel included terms for positive influence of winter habitat on reproduction rates, and negative influences of black duck density (i.e., compensation to harvest mortality). Individual models within each group (reproduction, survival) involved various combinations of these factors, and each was given an information theoretic weight for use in subsequent prediction. The reproduction model with highest

  14. The capital asset pricing model versus the three factor model: A United Kingdom Perspective

    Directory of Open Access Journals (Sweden)

    Chandra Shekhar Bhatnagar

    2013-07-01

    Full Text Available The Sharpe (1964, Lintner (1965 and Black (1972 Capital Asset Pricing Model (CAPM postulates that the equilibrium rates of return on all risky assets are a linear function of their covariance with the market portfolio. Recent work by Fama and French (1996, 2006 introduce a Three Factor Model that questions the “real world application” of the CAPM Theorem and its ability to explain stock returns as well as value premium effects in the United States market. This paper provides an out-of-sample perspective to the work of Fama and French (1996, 2006. Multiple regression is used to compare the performance of the CAPM, a split sample CAPM and the Three Factor Model in explaining observed stock returns and value premium effects in the United Kingdom market. The methodology of Fama and French (2006 was used as the framework for this study. The findings show that the Three Factor Model holds for the United Kingdom Market and is superior to the CAPM and the split sample CAPM in explaining both stock returns and value premium effects. The “real world application” of the CAPM is therefore not supported by the United Kingdom data.

  15. Multicollinearity in prognostic factor analyses using the EORTC QLQ-C30: identification and impact on model selection.

    Science.gov (United States)

    Van Steen, Kristel; Curran, Desmond; Kramer, Jocelyn; Molenberghs, Geert; Van Vreckem, Ann; Bottomley, Andrew; Sylvester, Richard

    2002-12-30

    Clinical and quality of life (QL) variables from an EORTC clinical trial of first line chemotherapy in advanced breast cancer were used in a prognostic factor analysis of survival and response to chemotherapy. For response, different final multivariate models were obtained from forward and backward selection methods, suggesting a disconcerting instability. Quality of life was measured using the EORTC QLQ-C30 questionnaire completed by patients. Subscales on the questionnaire are known to be highly correlated, and therefore it was hypothesized that multicollinearity contributed to model instability. A correlation matrix indicated that global QL was highly correlated with 7 out of 11 variables. In a first attempt to explore multicollinearity, we used global QL as dependent variable in a regression model with other QL subscales as predictors. Afterwards, standard diagnostic tests for multicollinearity were performed. An exploratory principal components analysis and factor analysis of the QL subscales identified at most three important components and indicated that inclusion of global QL made minimal difference to the loadings on each component, suggesting that it is redundant in the model. In a second approach, we advocate a bootstrap technique to assess the stability of the models. Based on these analyses and since global QL exacerbates problems of multicollinearity, we therefore recommend that global QL be excluded from prognostic factor analyses using the QLQ-C30. The prognostic factor analysis was rerun without global QL in the model, and selected the same significant prognostic factors as before. Copyright 2002 John Wiley & Sons, Ltd.

  16. Capturing the DSM-5 Alternative Personality Disorder Model Traits in the Five-Factor Model's Nomological Net.

    Science.gov (United States)

    Suzuki, Takakuni; Griffin, Sarah A; Samuel, Douglas B

    2017-04-01

    Several studies have shown structural and statistical similarities between the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5) alternative personality disorder model and the Five-Factor Model (FFM). However, no study to date has evaluated the nomological network similarities between the two models. The relations of the Revised NEO Personality Inventory (NEO PI-R) and the Personality Inventory for DSM-5 (PID-5) with relevant criterion variables were examined in a sample of 336 undergraduate students (M age  = 19.4; 59.8% female). The resulting profiles for each instrument were statistically compared for similarity. Four of the five domains of the two models have highly similar nomological networks, with the exception being FFM Openness to Experience and PID-5 Psychoticism. Further probing of that pair suggested that the NEO PI-R domain scores obscured meaningful similarity between PID-5 Psychoticism and specific aspects and lower-order facets of Openness. The results support the notion that the DSM-5 alternative personality disorder model trait domains represent variants of the FFM domains. Similarities of Openness and Psychoticism domains were supported when the lower-order aspects and facets of Openness domain were considered. The findings support the view that the DSM-5 trait model represents an instantiation of the FFM. © 2015 Wiley Periodicals, Inc.

  17. Relativistic form factors for hadrons with quark-model wave functions

    International Nuclear Information System (INIS)

    Stanley, D.P.; Robson, D.

    1982-01-01

    The relationship between relativistic form factors and quark-potential-model wave functions is examined using an improved version of an approach by Licht and Pagnamenta. Lorentz-contraction effects are expressed in terms of an effective hadron mass which varies as the square root of the number of quark constituents. The effective mass is calculated using the rest-frame wave functions from the mean-square momentum along the direction of the momentum transfer. Applications with the parameter-free approach are made to the elastic form factors of the pion, proton, and neutron using a Hamiltonian which simultaneously describes mesons and baryons. A comparison of the calculated radii for pions and kaons suggests that the measured kaon radius should be slightly smaller than the corresponding pion radius. The large negative squared charge radius for the neutron is partially explained via the quark model but a full description requires the inclusion of a small component of a pion ''cloud'' configuration. The problematic connection between the sizes of hadrons deduced from form factors and the ''measured'' values of average transverse momenta is reconciled in the present model

  18. Applying Petri nets in modelling the human factor

    International Nuclear Information System (INIS)

    Bedreaga, Luminita; Constntinescu, Cristina; Guzun, Basarab

    2007-01-01

    Usually, in the reliability analysis performed for complex systems, we determine the success probability to work with other performance indices, i.e. the likelihood associated with a given state. The possible values assigned to system states can be derived using inductive methods. If one wants to calculate the probability to occur a particular event in the system, then deductive methods should be applied. In the particular case of the human reliability analysis, as part of probabilistic safety analysis, the international regulatory commission have developed specific guides and procedures to perform such assessments. The paper presents the modality to obtain the human reliability quantification using the Petri nets approach. This is an efficient means to assess reliability systems because of their specific features. The examples showed in the paper are from human reliability documentation without a detailed human factor analysis (qualitative). We present human action modelling using event trees and Petri nets approach. The obtained results by these two kinds of methods are in good concordance. (authors)

  19. Interaction between ADH1C Arg272Gln and alcohol intake in relation to breast cancer risk suggests that ethanol is the causal factor in alcohol related breast cancer

    DEFF Research Database (Denmark)

    Benzon Larsen, Signe; Vogel, Ulla Birgitte; Christensen, Jane

    2010-01-01

    Alcohol is a risk factor for breast cancer. We wanted to determine if ADH polymorphisms which modify the rate of ethanol oxidation to acetaldehyde, were associated with breast cancer risk. We matched 809 postmenopausal breast cancer cases with 809 controls, nested within the prospective Diet......, Cancer and Health study. Among variant allele carriers of ADH1C Arg(272)Gln, alcohol intake increased the risk of breast cancer with 14% (95% CI: 1.04-1.24) per 10g alcohol/day, but not among homozygous wild type carriers (p for interaction=0.06). Thus, slow oxidation of ethanol seemed to be associated...

  20. Electrical tortuosity, Kozeny’s factor and cementation factor modelled for chalk

    DEFF Research Database (Denmark)

    Katika, Konstantina; Fabricius, Ida Lykke

    2015-01-01

    saturated core plugs to determine the cementation factor, m. This value differs from the one Archie used to describe his equation and best describes the formation factor based on experimental data. Based on this m, we determine the formation factor, F, and the tortuosity, τ. We use this value of τ...

  1. Inference of sigma factor controlled networks by using numerical modeling applied to microarray time series data of the germinating prokaryote.

    Science.gov (United States)

    Strakova, Eva; Zikova, Alice; Vohradsky, Jiri

    2014-01-01

    A computational model of gene expression was applied to a novel test set of microarray time series measurements to reveal regulatory interactions between transcriptional regulators represented by 45 sigma factors and the genes expressed during germination of a prokaryote Streptomyces coelicolor. Using microarrays, the first 5.5 h of the process was recorded in 13 time points, which provided a database of gene expression time series on genome-wide scale. The computational modeling of the kinetic relations between the sigma factors, individual genes and genes clustered according to the similarity of their expression kinetics identified kinetically plausible sigma factor-controlled networks. Using genome sequence annotations, functional groups of genes that were predominantly controlled by specific sigma factors were identified. Using external binding data complementing the modeling approach, specific genes involved in the control of the studied process were identified and their function suggested.

  2. The risk factors of laryngeal pathology in Korean adults using a decision tree model.

    Science.gov (United States)

    Byeon, Haewon

    2015-01-01

    The purpose of this study was to identify risk factors affecting laryngeal pathology in the Korean population and to evaluate the derived prediction model. Cross-sectional study. Data were drawn from the 2008 Korea National Health and Nutritional Examination Survey. The subjects were 3135 persons (1508 male and 2114 female) aged 19 years and older living in the community. The independent variables were age, sex, occupation, smoking, alcohol drinking, and self-reported voice problems. A decision tree analysis was done to identify risk factors for predicting a model of laryngeal pathology. The significant risk factors of laryngeal pathology were age, gender, occupation, smoking, and self-reported voice problem in decision tree model. Four significant paths were identified in the decision tree model for the prediction of laryngeal pathology. Those identified as high risk groups for laryngeal pathology included those who self-reported a voice problem, those who were males in their 50s who did not recognize a voice problem, those who were not economically active males in their 40s, and male workers aged 19 and over and under 50 or 60 and over who currently smoked. The results of this study suggest that individual risk factors, such as age, sex, occupation, health behavior, and self-reported voice problem, affect the onset of laryngeal pathology in a complex manner. Based on the results of this study, early management of the high-risk groups is needed for the prevention of laryngeal pathology. Copyright © 2015 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  3. Integrated traffic conflict model for estimating crash modification factors.

    Science.gov (United States)

    Shahdah, Usama; Saccomanno, Frank; Persaud, Bhagwant

    2014-10-01

    Crash modification factors (CMFs) for road safety treatments are usually obtained through observational models based on reported crashes. Observational Bayesian before-and-after methods have been applied to obtain more precise estimates of CMFs by accounting for the regression-to-the-mean bias inherent in naive methods. However, sufficient crash data reported over an extended period of time are needed to provide reliable estimates of treatment effects, a requirement that can be a challenge for certain types of treatment. In addition, these studies require that sites analyzed actually receive the treatment to which the CMF pertains. Another key issue with observational approaches is that they are not causal in nature, and as such, cannot provide a sound "behavioral" rationale for the treatment effect. Surrogate safety measures based on high risk vehicle interactions and traffic conflicts have been proposed to address this issue by providing a more "causal perspective" on lack of safety for different road and traffic conditions. The traffic conflict approach has been criticized, however, for lacking a formal link to observed and verified crashes, a difficulty that this paper attempts to resolve by presenting and investigating an alternative approach for estimating CMFs using simulated conflicts that are linked formally to observed crashes. The integrated CMF estimates are compared to estimates from an empirical Bayes (EB) crash-based before-and-after analysis for the same sample of treatment sites. The treatment considered involves changing left turn signal priority at Toronto signalized intersections from permissive to protected-permissive. The results are promising in that the proposed integrated method yields CMFs that closely match those obtained from the crash-based EB before-and-after analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Are Fit Indices Biased in Favor of Bi-Factor Models in Cognitive Ability Research?: A Comparison of Fit in Correlated Factors, Higher-Order, and Bi-Factor Models via Monte Carlo Simulations

    Directory of Open Access Journals (Sweden)

    Grant B. Morgan

    2015-02-01

    Full Text Available Bi-factor confirmatory factor models have been influential in research on cognitive abilities because they often better fit the data than correlated factors and higher-order models. They also instantiate a perspective that differs from that offered by other models. Motivated by previous work that hypothesized an inherent statistical bias of fit indices favoring the bi-factor model, we compared the fit of correlated factors, higher-order, and bi-factor models via Monte Carlo methods. When data were sampled from a true bi-factor structure, each of the approximate fit indices was more likely than not to identify the bi-factor solution as the best fitting. When samples were selected from a true multiple correlated factors structure, approximate fit indices were more likely overall to identify the correlated factors solution as the best fitting. In contrast, when samples were generated from a true higher-order structure, approximate fit indices tended to identify the bi-factor solution as best fitting. There was extensive overlap of fit values across the models regardless of true structure. Although one model may fit a given dataset best relative to the other models, each of the models tended to fit the data well in absolute terms. Given this variability, models must also be judged on substantive and conceptual grounds.

  5. Influencing Factors and Consequences of Workplace Bullying among Nurses: A Structural Equation Modeling

    Directory of Open Access Journals (Sweden)

    Seonyoung Yun, PhD, RN

    2018-03-01

    Full Text Available Purpose: The purpose of this study was to build and test a model outlining the factors related to workplace bullying among nurses. The hypothesized model included authentic leadership and a relationship-oriented organizational culture as influencing factors, symptom experience and turnover intention as consequences, and positive psychological capital as a mediator of workplace bullying among nurses. Methods: We obtained structured questionnaire data from 301 nurses working at hospitals in South Korea. Based on these data, the developed model was verified via a structural equation modeling analysis using SPSS and AMOS program. Results: The fit indices of the hypothesized model satisfied recommended levels; χ2 = 397.58 (p < .001, normed χ2 (χ2/df = 1.82, RMR = .05, TLI = .93, CFI = .94, RMSEA = .05. A relationship-oriented organizational culture had a direct effect on workplace bullying (β = −.48, p < .001. Furthermore, workplace bullying had a direct effect on symptom experience (β = .36, p < .001, and this relationship was mediated by positive psychological capital (β = .15, p = .003. Workplace bullying also had an indirect effect on turnover intention (β = .20, p = .007. Finally, symptom experience had a direct effect on turnover intention (β = .31, p = .002. Conclusion: These results suggest that workplace bullying among nurses may be prevented by constructing a relationship-oriented organizational culture, as long as employees have sufficient positive psychological capital. In this regard, workplace bullying among nurses should be addressed using a comprehensive strategy that considers both individual and organizational factors. Keywords: bullying, leadership, nurses, organizational culture, personnel turnover

  6. Transcriptomic profiling of TK2 deficient human skeletal muscle suggests a role for the p53 signalling pathway and identifies growth and differentiation factor-15 as a potential novel biomarker for mitochondrial myopathies

    Science.gov (United States)

    2014-01-01

    Background Mutations in the gene encoding thymidine kinase 2 (TK2) result in the myopathic form of mitochondrial DNA depletion syndrome which is a mitochondrial encephalomyopathy presenting in children. In order to unveil some of the mechanisms involved in this pathology and to identify potential biomarkers and therapeutic targets we have investigated the gene expression profile of human skeletal muscle deficient for TK2 using cDNA microarrays. Results We have analysed the whole transcriptome of skeletal muscle from patients with TK2 mutations and compared it to normal muscle and to muscle from patients with other mitochondrial myopathies. We have identified a set of over 700 genes which are differentially expressed in TK2 deficient muscle. Bioinformatics analysis reveals important changes in muscle metabolism, in particular, in glucose and glycogen utilisation, and activation of the starvation response which affects aminoacid and lipid metabolism. We have identified those transcriptional regulators which are likely to be responsible for the observed changes in gene expression. Conclusion Our data point towards the tumor suppressor p53 as the regulator at the centre of a network of genes which are responsible for a coordinated response to TK2 mutations which involves inflammation, activation of muscle cell death by apoptosis and induction of growth and differentiation factor 15 (GDF-15) in muscle and serum. We propose that GDF-15 may represent a potential novel biomarker for mitochondrial dysfunction although further studies are required. PMID:24484525

  7. Assessing the model transferability for prediction of transcription factor binding sites based on chromatin accessibility.

    Science.gov (United States)

    Liu, Sheng; Zibetti, Cristina; Wan, Jun; Wang, Guohua; Blackshaw, Seth; Qian, Jiang

    2017-07-27

    Computational prediction of transcription factor (TF) binding sites in different cell types is challenging. Recent technology development allows us to determine the genome-wide chromatin accessibility in various cellular and developmental contexts. The chromatin accessibility profiles provide useful information in prediction of TF binding events in various physiological conditions. Furthermore, ChIP-Seq analysis was used to determine genome-wide binding sites for a range of different TFs in multiple cell types. Integration of these two types of genomic information can improve the prediction of TF binding events. We assessed to what extent a model built upon on other TFs and/or other cell types could be used to predict the binding sites of TFs of interest. A random forest model was built using a set of cell type-independent features such as specific sequences recognized by the TFs and evolutionary conservation, as well as cell type-specific features derived from chromatin accessibility data. Our analysis suggested that the models learned from other TFs and/or cell lines performed almost as well as the model learned from the target TF in the cell type of interest. Interestingly, models based on multiple TFs performed better than single-TF models. Finally, we proposed a universal model, BPAC, which was generated using ChIP-Seq data from multiple TFs in various cell types. Integrating chromatin accessibility information with sequence information improves prediction of TF binding.The prediction of TF binding is transferable across TFs and/or cell lines suggesting there are a set of universal "rules". A computational tool was developed to predict TF binding sites based on the universal "rules".

  8. DETERMINANTS OF SOVEREIGN RATING: FACTOR BASED ORDERED PROBIT MODELS FOR PANEL DATA ANALYSIS MODELING FRAMEWORK

    Directory of Open Access Journals (Sweden)

    Dilek Teker

    2013-01-01

    Full Text Available The aim of this research is to compose a new rating methodology and provide credit notches to 23 countries which of 13 are developed and 10 are emerging. There are various literature that explains the determinants of credit ratings. Following the literature, we select 11 variables for our model which of 5 are eliminated by the factor analysis. We use specific dummies to investigate the structural breaks in time and cross section such as pre crises, post crises, BRIC membership, EU membership, OPEC membership, shipbuilder country and platinum reserved country. Then we run an ordered probit model and give credit notches to the countries. We use FITCH ratings as benchmark. Thus, at the end we compare the notches of FITCH with the ones we derive out of our estimated model.

  9. E-Learning and Social Media Motivation Factor Model

    Science.gov (United States)

    Rosli, Mohd Shafie; Saleh, Nor Shela; Aris, Baharuddin; Ahmad, Maizah Hura; Sejzi, Abbas Abjoli; Shamsudin, Nur Amalina

    2016-01-01

    The aims of this study are to probe into the motivational factors toward the usage of e-learning and social media among educational technology postgraduate students in the Faculty of Education, Universiti Teknologi Malaysia. This study had involved 70 respondents via the means of a questionnaire. Four factors have been studied, named, the factor…

  10. g-Factors in the (sdg) boson model

    Science.gov (United States)

    Morrison, I.

    1986-07-01

    The role of the g-boson in producing first-order variations in the g-factors of states in rotational nuclei is investigated. It is shown that the g-boson is unlikely to contribute directly to any observed g-factor variations in the ground-state band.

  11. G-factors in the (sdg) boson model

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, I.

    1986-07-24

    The role of the g-boson in producing first-order variations in the g-factors of states in rotational nuclei is investigated. It is shown that the g-boson is unlikely to contribute directly to any observed g-factor variations in the ground-state band.

  12. Analytic properties of form factors in strictly confining models

    International Nuclear Information System (INIS)

    Csikor, F.

    1979-12-01

    An argument is presented showing that strict confinement implies the possible existence of an (unwanted) branch point at q 2 =0 in the form factors. In case of a bag extended to infinity in the relative time, the branch point is certainly there (provided that the form factor is non zero at q 2 =0). (author)

  13. Critical Success Factors for E-Learning Acceptance: Confirmatory Factor Models

    Science.gov (United States)

    Selim, Hassan M.

    2007-01-01

    E-learning, one of the tools emerged from information technology, has been integrated in many university programs. There are several factors that need to be considered while developing or implementing university curriculums that offer e-learning based courses. This paper is intended to specify e-learning critical success factors (CSFs) as…

  14. John Carroll’s Views on Intelligence: Bi-Factor vs. Higher-Order Models

    Directory of Open Access Journals (Sweden)

    A. Alexander Beaujean

    2015-10-01

    Full Text Available The development of factor models is inextricably tied to the history of intelligence research. One of the most commonly-cited scholars in the field is John Carroll, whose three-stratum theory of cognitive ability has been one of the most influential models of cognitive ability in the past 20 years. Nonetheless, there is disagreement about how Carroll conceptualized the factors in his model. Some argue that his model is best represented through a higher-order model, while others argue that a bi-factor model is a better representation. Carroll was explicit about what he perceived the best way to represent his model, but his writings are not always easy to understand. In this article, I clarify his position by first describing the details and implications of bi-factor and higher-order models then show that Carroll’s published views are better represented by a bi-factor model.

  15. The effect of modifiable risk factors on geographic mortality differentials: a modelling study

    Directory of Open Access Journals (Sweden)

    Stevenson Christopher E

    2012-01-01

    Full Text Available Abstract Background Australian mortality rates are higher in regional and remote areas than in major cities. The degree to which this is driven by variation in modifiable risk factors is unknown. Methods We applied a risk prediction equation incorporating smoking, cholesterol and blood pressure to a national, population based survey to project all-causes mortality risk by geographic region. We then modelled life expectancies at different levels of mortality risk by geographic region using a risk percentiles model. Finally we set high values of each risk factor to a target level and modelled the subsequent shift in the population to lower levels of mortality risk and longer life expectancy. Results Survival is poorer in both Inner Regional and Outer Regional/Remote areas compared to Major Cities for men and women at both high and low levels of predicted mortality risk. For men smoking, high cholesterol and high systolic blood pressure were each associated with the mortality difference between Major Cities and Outer Regional/Remote areas--accounting for 21.4%, 20.3% and 7.7% of the difference respectively. For women smoking and high cholesterol accounted for 29.4% and 24.0% of the difference respectively but high blood pressure did not contribute to the observed mortality differences. The three risk factors taken together accounted for 45.4% (men and 35.6% (women of the mortality difference. The contribution of risk factors to the corresponding differences for inner regional areas was smaller, with only high cholesterol and smoking contributing to the difference in men-- accounting for 8.8% and 6.3% respectively-- and only smoking contributing to the difference in women--accounting for 12.3%. Conclusions These results suggest that health intervention programs aimed at smoking, blood pressure and total cholesterol could have a substantial impact on mortality inequities for Outer Regional/Remote areas.

  16. A Dynamic Multi-Level Factor Model with Long-Range Dependence

    DEFF Research Database (Denmark)

    Ergemen, Yunus Emre; Rodríguez-Caballero, Carlos Vladimir

    A dynamic multi-level factor model with stationary or nonstationary global and regional factors is proposed. In the model, persistence in global and regional common factors as well as innovations allows for the study of fractional cointegrating relationships. Estimation of global and regional...

  17. Parental Expression of Disappointment: Should It Be a Factor in Hoffman's Model of Parental Discipline?

    Science.gov (United States)

    Patrick, Renee B.; Gibbs, John C.

    2007-01-01

    The authors addressed whether parental expression of disappointment should be included as a distinct factor in M. L. Hoffman's (2000) well-established typology of parenting styles (induction, love withdrawal, power assertion). Hoffman's 3-factor model, along with a more inclusive 4-factor model (induction, love withdrawal, power assertion, and…

  18. Modeling the factors that influence knowledge transfer in mergers and acquisitions

    Institute of Scientific and Technical Information of China (English)

    YU Haiyan; LIANG Zhanping

    2010-01-01

    This paper constructs a model on the factors that influence knowledge transfer in mergers and acquisitions (M&A) and validates it via questionnaire surveys.Using 125 valid collected questionnaires,multiple linear regression analysis and hierarchical regression analysis showed that five out of the ten factors had a positive effect on knowledge transfer effect.The ranking of factor importance,from high to low,was knowledge explicitness,relationship quality,learning intent,advanced transfer activities,and learning capability,which is fairly consistent with positive factors observed in other interorganizational knowledge transfer researches.Our results also showed that one of the control variables (size of acquired firm) had neither a direct or indirect effect on knowledge transfer in M&A.Additionally,our research found that knowledge distance and degree of M&A integration had a positive influence on knowledge transfer effect at the early stage after M&A,but had a negative influence at the late stage.Based on this research,several suggestions for knowledge transfer in M&A are proposed.

  19. Modeling the factors that influence knowledge transfer in mergers and acquisitions

    Institute of Scientific and Technical Information of China (English)

    YU; Haiyan; LIANG; Zhanping

    2010-01-01

    This paper constructs a model on the factors that influence knowledge transfer in mergers and acquisitions(M&A)and validates it via questionnaire surveys.Using 125valid collected questionnaires,multiple linear regression analysis and hierarchical regression analysis showed that five out of the ten factors had a positive effect on knowledge transfer effect.The ranking of factor importance,from high to low,was knowledge explicitness,relationship quality,learning intent,advanced transfer activities,and learning capability,which is fairly consistent with positive factors observed in other interorganizational knowledge transfer researches.Our results also showed that one of the control variables(size of acquired firm)had neither a direct or indirect effect on knowledge transfer in M&A.Additionally,our research found that knowledge distance and degree of M&A integration had a positive influence on knowledge transfer effect at the early stage after M&A,but had a negative influence at the late stage.Based on this research,several suggestions for knowledge transfer in M&A are proposed.

  20. Verification of the model of predisposition in triathlon – structural model of confirmative factor analysis

    Directory of Open Access Journals (Sweden)

    Lenka Kovářová

    2012-09-01

    Full Text Available BACKGROUND: The triathlon is a combination of three different types of sport – swimming, cycling, and running. Each of these requires different top level predispositions and complex approach to talent selection is a rather difficult process. Attempts to identify assumptions in the triathlon have so far been specific and focused only on some groups of predispositions (physiology, motor tests, and psychology. The latest studies missed the structural approach and were based on determinants of sport performance, theory of sports training and expert assessment. OBJECTIVE: The aim of our study was to verify the model of predisposition in the short triathlon for talent assessment of young male athletes age 17–20 years. METHODS: The research sample consisted of 55 top level triathletes – men, who were included in the Government supported sports talent programme in the Czech Republic at the age of 17–20 years. We used a confirmative factor analysis (FA and Path diagram to verify the model, which allow us to explain mutual relationships among observed variables. For statistical data processing we used a structure equating modeling (SEM by software Lisrel L88. RESULTS: The study confirms best structural model for talent selection in triathlon at the age of 17–20 years old men, which composed seventeen indicators (tests and explained 91% of all cross-correlations (Goodness of Fit Index /GFI/ 0.91, Root Mean Square Residual /RMSR/ 0.13. Tests for predispositions in triathlons were grouped into five items, three motor predispositions (swimming, cycling and running skills, aerobic and psychological predispositions. Aerobic predispositions showed the highest importance to the assumptions to the general factor (1.00; 0. Running predispositions were measured as a very significant factor (–0.85; 0.28 which confirms importance of this critical stage of the race. Lower factor weight showed clusters of swimming (–0.61; 0.63 and cycling (0.53; 0

  1. Spatial aspects affecting acidification factors in European acidification modelling

    NARCIS (Netherlands)

    Bellekom, S.; Hettelingh, J. -P.; Aben, J.

    Plain linear models have recently been used in methodologies to model fate and transport for assessing acidification in life cycle impact assessment (LCIA), or in support of air pollution abatement policies. These models originate from a statistical analysis of the relationship between inputs and

  2. Bayes factor covariance testing in item response models

    NARCIS (Netherlands)

    Fox, J.P.; Mulder, J.; Sinharay, Sandip

    2017-01-01

    Two marginal one-parameter item response theory models are introduced, by integrating out the latent variable or random item parameter. It is shown that both marginal response models are multivariate (probit) models with a compound symmetry covariance structure. Several common hypotheses concerning

  3. Bayes Factor Covariance Testing in Item Response Models

    NARCIS (Netherlands)

    Fox, Jean-Paul; Mulder, Joris; Sinharay, Sandip

    2017-01-01

    Two marginal one-parameter item response theory models are introduced, by integrating out the latent variable or random item parameter. It is shown that both marginal response models are multivariate (probit) models with a compound symmetry covariance structure. Several common hypotheses concerning

  4. The Meaning of Higher-Order Factors in Reflective-Measurement Models

    Science.gov (United States)

    Eid, Michael; Koch, Tobias

    2014-01-01

    Higher-order factor analysis is a widely used approach for analyzing the structure of a multidimensional test. Whenever first-order factors are correlated researchers are tempted to apply a higher-order factor model. But is this reasonable? What do the higher-order factors measure? What is their meaning? Willoughby, Holochwost, Blanton, and Blair…

  5. Motivation and personality: relationships between putative motive dimensions and the five factor model of personality.

    Science.gov (United States)

    Bernard, Larry C

    2010-04-01

    There are few multidimensional measures of individual differences in motivation available. The Assessment of Individual Motives-Questionnaire assesses 15 putative dimensions of motivation. The dimensions are based on evolutionary theory and preliminary evidence suggests the motive scales have good psychometric properties. The scales are reliable and there is evidence of their consensual validity (convergence of self-other ratings) and behavioral validity (relationships with self-other reported behaviors of social importance). Additional validity research is necessary, however, especially with respect to current models of personality. The present study tested two general and 24 specific hypotheses based on proposed evolutionary advantages/disadvantages and fitness benefits/costs of the five-factor model of personality together with the new motive scales in a sample of 424 participants (M age=28.8 yr., SD=14.6). Results were largely supportive of the hypotheses. These results support the validity of new motive dimensions and increase understanding of the five-factor model of personality.

  6. A Model of Factors Contributing to STEM Learning and Career Orientation

    Science.gov (United States)

    Nugent, Gwen; Barker, Bradley; Welch, Greg; Grandgenett, Neal; Wu, ChaoRong; Nelson, Carl

    2015-05-01

    The purpose of this research was to develop and test a model of factors contributing to science, technology, engineering, and mathematics (STEM) learning and career orientation, examining the complex paths and relationships among social, motivational, and instructional factors underlying these outcomes for middle school youth. Social cognitive career theory provided the foundation for the research because of its emphasis on explaining mechanisms which influence both career orientations and academic performance. Key constructs investigated were youth STEM interest, self-efficacy, and career outcome expectancy (consequences of particular actions). The study also investigated the effects of prior knowledge, use of problem-solving learning strategies, and the support and influence of informal educators, family members, and peers. A structural equation model was developed, and structural equation modeling procedures were used to test proposed relationships between these constructs. Results showed that educators, peers, and family-influenced youth STEM interest, which in turn predicted their STEM self-efficacy and career outcome expectancy. STEM career orientation was fostered by youth-expected outcomes for such careers. Results suggest that students' pathways to STEM careers and learning can be largely explained by these constructs, and underscore the importance of youth STEM interest.

  7. Effective factors contraceptive use by logistic regression model in Tehran, 1996

    Directory of Open Access Journals (Sweden)

    Ramezani F

    1999-07-01

    Full Text Available Despite unwillingness to fertility, about 30% of couples do not use any kind of contraception and this will lead to unwanted pregnancy. In this clinical trial study, 4177 subjects who had at least one alive child, and delivered in one of the 12 university hospitals in Tehran were recruited. This study was conducted in 1996. The questionnaire included some questions about contraceptive use, their attitudes about unwantedness or wantedness of their current pregnancies. Data were analysed using a Logistic Regrassion Model. Results showed that 20.3% of those who had no fertility intention, did not use any kind of contraception methods, 41.1% of the subjects who were using a contraception method before pregnancy, had got pregnant unwantedly. Based on Logistic Regression Model; age, education, previous familiarity of women with contraception methods and husband's education were the most significant factors in contraceptive use. Subjects who were 20 years old and less or 35 years old and more and illeterate subjects were at higher risk for unuse of contraception methods. This risk was not related to the gender of their children that suggests a positive change in their perspectives towards sex and the number of children. It is suggested that health politicians choose an appropriate model to enhance the literacy, education and counseling for the correct usage of contraceptives and prevention of unwanted pregnancy.

  8. Cultural factors in a mobile phone adoption and usage model

    CSIR Research Space (South Africa)

    Van Biljon, J

    2008-01-01

    Full Text Available . Although the feature driven and usability focus carry value, it is not the full picture. There is also an alternative or wider perspective: mobile phone use is influenced by demographic, social, cultural, and contextual factors that complicate...

  9. Cholesterol, Triglycerides, and the Five-Factor Model of Personality

    OpenAIRE

    Sutin, Angelina R.; Terracciano, Antonio; Deiana, Barbara; Uda, Manuela; Schlessinger, David; Lakatta, Edward G.; Costa, Paul T.

    2010-01-01

    Unhealthy lipid levels are among the leading controllable risk factors for coronary heart disease. To identify the psychological factors associated with dyslipidemia, this study investigates the personality correlates of cholesterol (total, LDL, and HDL) and triglycerides. A community-based sample (N=5,532) from Sardinia, Italy, had their cholesterol and triglyceride levels assessed and completed a comprehensive personality questionnaire, the NEO-PI-R. All analyses controlled for age, sex, BM...

  10. Cluster models, factors and characteristics for the competitive advantage of Lithuanian Maritime sector

    OpenAIRE

    Viederytė, Rasa; Didžiokas, Rimantas

    2014-01-01

    Paper analyses several cluster models on the basis of competitiveness: Nine-factor model, Double diamond model, Funnel model of cluster determinants, Destination Competitiveness and sustainability models, which are related to Porter’s Diamond model and concentrate to the classical one - adopt M. Porter’s Diamond model methodology to the evaluation of Lithuanian Maritime sector’s clustering on the basis of competitiveness. Despite the advances in cluster research, this model remains a complex ...

  11. Towards an Enhancement of Organizational Information Security through Threat Factor Profiling (TFP) Model

    Science.gov (United States)

    Sidi, Fatimah; Daud, Maslina; Ahmad, Sabariah; Zainuddin, Naqliyah; Anneisa Abdullah, Syafiqa; Jabar, Marzanah A.; Suriani Affendey, Lilly; Ishak, Iskandar; Sharef, Nurfadhlina Mohd; Zolkepli, Maslina; Nur Majdina Nordin, Fatin; Amat Sejani, Hashimah; Ramadzan Hairani, Saiful

    2017-09-01

    Information security has been identified by organizations as part of internal operations that need to be well implemented and protected. This is because each day the organizations face a high probability of increase of threats to their networks and services that will lead to information security issues. Thus, effective information security management is required in order to protect their information assets. Threat profiling is a method that can be used by an organization to address the security challenges. Threat profiling allows analysts to understand and organize intelligent information related to threat groups. This paper presents a comparative analysis that was conducted to study the existing threat profiling models. It was found that existing threat models were constructed based on specific objectives, thus each model is limited to only certain components or factors such as assets, threat sources, countermeasures, threat agents, threat outcomes and threat actors. It is suggested that threat profiling can be improved by the combination of components found in each existing threat profiling model/framework. The proposed model can be used by an organization in executing a proactive approach to incident management.

  12. Factors accounting for youth suicide attempt in Hong Kong: a model building.

    Science.gov (United States)

    Wan, Gloria W Y; Leung, Patrick W L

    2010-10-01

    This study aimed at proposing and testing a conceptual model of youth suicide attempt. We proposed a model that began with family factors such as a history of physical abuse and parental divorce/separation. Family relationship, presence of psychopathology, life stressors, and suicide ideation were postulated as mediators, leading to youth suicide attempt. The stepwise entry of the risk factors to a logistic regression model defined their proximity as related to suicide attempt. Path analysis further refined our proposed model of youth suicide attempt. Our originally proposed model was largely confirmed. The main revision was dropping parental divorce/separation as a risk factor in the model due to lack of significant contribution when examined alongside with other risk factors. This model was cross-validated by gender. This study moved research on youth suicide from identification of individual risk factors to model building, integrating separate findings of the past studies.

  13. Do astrophysical measurements suggest massive neutrinos?

    International Nuclear Information System (INIS)

    Ali, M.; Fazal-e-Aleem; Rashid, H.

    1996-01-01

    We discuss the solar neutrino puzzle and suggest modification in the standard solar model. It has been observed that the discrepancy between experimental measurements and theoretically produced values can be removed by considering neutrinos to process non-zero mass. (author)

  14. The role of tag suggestions in folksonomies

    NARCIS (Netherlands)

    Bollen, D.G.F.M.; Halpin, H.

    2009-01-01

    Most tagging systems support the user in the tag selection process by providing tag suggestions, or recommendations, based on a popularity measurement of tags other users provided when tagging the same resource. The majority of theories and mathematical models of tagging found in the literature

  15. Maximum Likelihood Dynamic Factor Modeling for Arbitrary "N" and "T" Using SEM

    Science.gov (United States)

    Voelkle, Manuel C.; Oud, Johan H. L.; von Oertzen, Timo; Lindenberger, Ulman

    2012-01-01

    This article has 3 objectives that build on each other. First, we demonstrate how to obtain maximum likelihood estimates for dynamic factor models (the direct autoregressive factor score model) with arbitrary "T" and "N" by means of structural equation modeling (SEM) and compare the approach to existing methods. Second, we go beyond standard time…

  16. Factors that affect postnatal bone growth retardation in the twitcher murine model of Krabbe disease.

    Science.gov (United States)

    Contreras, Miguel Agustin; Ries, William Louis; Shanmugarajan, Srinivasan; Arboleda, Gonzalo; Singh, Inderjit; Singh, Avtar Kaur

    2010-01-01

    Krabbe disease is an inherited lysosomal disorder in which galactosylsphingosine (psychosine) accumulates mainly in the central nervous system. To gain insight into the possible mechanism(s) that may be participating in the inhibition of the postnatal somatic growth described in the animal model of this disease (twitcher mouse, twi), we studied their femora. This study reports that twi femora are smaller than of those of wild type (wt), and present with abnormality of marrow cellularity, bone deposition (osteoblastic function), and osteoclastic activity. Furthermore, lipidomic analysis indicates altered sphingolipid homeostasis, but without significant changes in the levels of sphingolipid-derived intermediates of cell death (ceramide) or the levels of the osteoclast-osteoblast coupling factor (sphingosine-1-phosphate). However, there was significant accumulation of psychosine in the femora of adult twi animals as compared to wt, without induction of tumor necrosis factor-alpha or interleukin-6. Analysis of insulin-like growth factor-1 (IGF-1) plasma levels, a liver secreted hormone known to play a role in bone growth, indicated a drastic reduction in twi animals when compared to wt. To identify the cause of the decrease, we examined the IGF-1 mRNA expression and protein levels in the liver. The results indicated a significant reduction of IGF-1 mRNA as well as protein levels in the liver from twi as compared to wt littermates. Our data suggest that a combination of endogenous (psychosine) and endocrine (IGF-1) factors play a role in the inhibition of postnatal bone growth in twi mice; and further suggest that derangements of liver function may be contributing, at least in part, to this alteration. Copyright 2010 Elsevier B.V. All rights reserved.

  17. East meets West: the influence of racial, ethnic and cultural risk factors on cardiac surgical risk model performance.

    Science.gov (United States)

    Soo-Hoo, Sarah; Nemeth, Samantha; Baser, Onur; Argenziano, Michael; Kurlansky, Paul

    2018-01-01

    To explore the impact of racial and ethnic diversity on the performance of cardiac surgical risk models, the Chinese SinoSCORE was compared with the Society of Thoracic Surgeons (STS) risk model in a diverse American population. The SinoSCORE risk model was applied to 13 969 consecutive coronary artery bypass surgery patients from twelve American institutions. SinoSCORE risk factors were entered into a logistic regression to create a 'derived' SinoSCORE whose performance was compared with that of the STS risk model. Observed mortality was 1.51% (66% of that predicted by STS model). The SinoSCORE 'low-risk' group had a mortality of 0.15%±0.04%, while the medium-risk and high-risk groups had mortalities of 0.35%±0.06% and 2.13%±0.14%, respectively. The derived SinoSCORE model had a relatively good discrimination (area under of the curve (AUC)=0.785) compared with that of the STS risk score (AUC=0.811; P=0.18 comparing the two). However, specific factors that were significant in the original SinoSCORE but that lacked significance in our derived model included body mass index, preoperative atrial fibrillation and chronic obstructive pulmonary disease. SinoSCORE demonstrated limited discrimination when applied to an American population. The derived SinoSCORE had a discrimination comparable with that of the STS, suggesting underlying similarities of physiological substrate undergoing surgery. However, differential influence of various risk factors suggests that there may be varying degrees of importance and interactions between risk factors. Clinicians should exercise caution when applying risk models across varying populations due to potential differences that racial, ethnic and geographic factors may play in cardiac disease and surgical outcomes.

  18. Modeling structural, dyadic, and individual factors: the inclusion and exclusion model of HIV related behavior.

    Science.gov (United States)

    Albarracin, Dolores; Tannenbaum, Melanie B; Glasman, Laura R; Rothman, Alexander J

    2010-12-01

    Changing HIV-related behaviors requires addressing the individual, dyadic, and structural influences that shape them. This supplement of AIDS & Behavior presents frameworks that integrate these three influences on behavior. Concepts from these frameworks were selected to model the processes by which structural factors affect individual HIV-related behavior. In the Inclusion/Exclusion Model, material and symbolic inclusions and exclusions (sharing versus denying resources) regulate individuals' ability and motivation to detect, prevent, and treat HIV. Structural interventions create inclusions that increase one's ability or motivation to perform these behaviors or exclusions that hinder one's ability or motivation to execute counterproductive behaviors. The need to expand research regarding multilevel influences on HIV-related behavior is also discussed, particularly concerning further understanding of sustained behavior change and effective dissemination of evidence-based intervention strategies.

  19. Copula Based Factorization in Bayesian Multivariate Infinite Mixture Models

    OpenAIRE

    Martin Burda; Artem Prokhorov

    2012-01-01

    Bayesian nonparametric models based on infinite mixtures of density kernels have been recently gaining in popularity due to their flexibility and feasibility of implementation even in complicated modeling scenarios. In economics, they have been particularly useful in estimating nonparametric distributions of latent variables. However, these models have been rarely applied in more than one dimension. Indeed, the multivariate case suffers from the curse of dimensionality, with a rapidly increas...

  20. Stochastic factor model for electricity spot price-the case of the Nordic market

    International Nuclear Information System (INIS)

    Vehvilaeinen, Iivo; Pyykkoenen, Tuomas

    2005-01-01

    This paper presents a stochastic factor based approach to mid-term modeling of spot prices in deregulated electricity markets. The fundamentals affecting the spot price are modeled independently and a market equilibrium model combines them to form spot price. Main advantage of the model is the transparency of the generated prices because each underlying factor and the dynamics between factors can be modeled and studied in detail. Paper shows realistic numerical examples on the forerunner Scandinavian electricity market. The model is used to price an exotic electricity derivative

  1. Stochastic factor model for electricity spot price - the case of the Nordic market

    International Nuclear Information System (INIS)

    Vehvilainen, I.; Pyykkoenen, T.

    2005-01-01

    This paper presents a stochastic factor based approach to mid-term modeling of spot prices in deregulated electricity markets. The fundamentals affecting the spot price are modeled independently and a market equilibrium model combines them to form spot price. Main advantage of the model is the transparency of the generated prices because each underlying factor and the dynamics between factors can be modeled and studied in detail. Paper shows realistic numerical examples on the forerunner Scandinavian electricity market. The model is used to price an exotic electricity derivative. (author)

  2. Agent-based modeling of oxygen-responsive transcription factors in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Hao Bai

    2014-04-01

    Full Text Available In the presence of oxygen (O2 the model bacterium Escherichia coli is able to conserve energy by aerobic respiration. Two major terminal oxidases are involved in this process - Cyo has a relatively low affinity for O2 but is able to pump protons and hence is energetically efficient; Cyd has a high affinity for O2 but does not pump protons. When E. coli encounters environments with different O2 availabilities, the expression of the genes encoding the alternative terminal oxidases, the cydAB and cyoABCDE operons, are regulated by two O2-responsive transcription factors, ArcA (an indirect O2 sensor and FNR (a direct O2 sensor. It has been suggested that O2-consumption by the terminal oxidases located at the cytoplasmic membrane significantly affects the activities of ArcA and FNR in the bacterial nucleoid. In this study, an agent-based modeling approach has been taken to spatially simulate the uptake and consumption of O2 by E. coli and the consequent modulation of ArcA and FNR activities based on experimental data obtained from highly controlled chemostat cultures. The molecules of O2, transcription factors and terminal oxidases are treated as individual agents and their behaviors and interactions are imitated in a simulated 3-D E. coli cell. The model implies that there are two barriers that dampen the response of FNR to O2, i.e. consumption of O2 at the membrane by the terminal oxidases and reaction of O2 with cytoplasmic FNR. Analysis of FNR variants suggested that the monomer-dimer transition is the key step in FNR-mediated repression of gene expression.

  3. Moderating Factors of Video-Modeling with Other as Model: A Meta-Analysis of Single-Case Studies

    Science.gov (United States)

    Mason, Rose A.; Ganz, Jennifer B.; Parker, Richard I.; Burke, Mack D.; Camargo, Siglia P.

    2012-01-01

    Video modeling with other as model (VMO) is a more practical method for implementing video-based modeling techniques, such as video self-modeling, which requires significantly more editing. Despite this, identification of contextual factors such as participant characteristics and targeted outcomes that moderate the effectiveness of VMO has not…

  4. Factorization of standard model cross sections at ultrahigh energy

    Science.gov (United States)

    Chien, Yang-Ting; Li, Hsiang-nan

    2018-03-01

    The factorization theorem for organizing multiple electroweak boson emissions at future colliders with energy far above the electroweak scale is formulated. Taking the inclusive muon-pair production in electron-positron collisions as an example, we argue that the summation over isospins is demanded for constructing the universal distributions of leptons and gauge bosons in an electron. These parton distributions are shown to have the same infrared structure in the phases of broken and unbroken electroweak symmetry, an observation consistent with the Goldstone equivalence theorem. The electroweak factorization of processes involving protons is sketched, with an emphasis on the subtlety of the scalar distributions. This formalism, in which electroweak shower effects are handled from the viewpoint of factorization theorem for the first time, is an adequate framework for collider physics at ultra high energy.

  5. Adolescent Girls' Self-Concept and Its Related Factors Based on Roy Adaptation Model

    OpenAIRE

    M. Basiri Moghadam; SH. Khosravan; L. Sadeghmoghadam; N. Ebrahimi Senoo

    2017-01-01

    Aims: One of the most important factors of individual health in the adolescents is the self-concept. As a nursing model, the Roy adaptation model mainly investigates the factor. The aim of the study was to investigate the self-concept and its related factors in the adolescent girls in Gonabad Township, based on the Roy adaptation model. Instrument & Methods: In the descriptive cross-sectional study, 270 adolescent girls were studied in Gonabad Township, Iran, in 2015. The subjects were s...

  6. Form factors and structure functions of hadrons in parton model

    International Nuclear Information System (INIS)

    Volkonskij, N.Yu.

    1979-01-01

    The hadron charge form factors and their relation to the deep-inelastic lepton-production structure functions in the regions of asymptotically high and small momentum transfer Q 2 are studied. The nucleon and pion charge radii are calculated. The results of calculations are in good agreement with the experimental data. The K- and D-meson charge radii are estimated. In the region of asymptotically high Q 2 the possibility of Drell-Yan-West relation violation is analyzed. It is shown, that for pseudoscalar mesons this relation is violated. The relation between the proton and neutron form factor asymptotics is obtained

  7. The Conceptual Framework of Factors Affecting Shared Mental Model

    Science.gov (United States)

    Lee, Miyoung; Johnson, Tristan; Lee, Youngmin; O'Connor, Debra; Khalil, Mohammed

    2004-01-01

    Many researchers have paid attention to the potentiality and possibility of the shared mental model because it enables teammates to perform their job better by sharing team knowledge, skills, attitudes, dynamics and environments. Even though theoretical and experimental evidences provide a close relationship between the shared mental model and…

  8. First International Workshop on Human Factors in Modeling (HuFaMo 2015)

    DEFF Research Database (Denmark)

    Störrle, Harald; Chaudron, Michel R. V.; Amaral, Vasco

    2015-01-01

    human factors in modeling. Our goal is to improve the state of the science and professionalism in empirical research in the Model Based Engineering community. Typical examples of research questions might consider the usability of a certain approach, such as a method or language, or the emotional states......Modeling is a human-intensive enterprise. As such, many research questions related to modeling can only be answered by empirical studies employing human factors. The International Workshop Series on Human Factors in Modeling (HuFaMo) is dedicated to the discussion of empirical research involving...... or personal judgements of modelers. While concerned with foundations and framework support for modeling, the community has been somehow neglecting the issue of human factors in this context. There is a growing need from the community concerned with quality factors to understand the best practices...

  9. Research on cognitive reliability model for main control room considering human factors in nuclear power plants

    International Nuclear Information System (INIS)

    Jiang Jianjun; Zhang Li; Wang Yiqun; Zhang Kun; Peng Yuyuan; Zhou Cheng

    2012-01-01

    Facing the shortcomings of the traditional cognitive factors and cognitive model, this paper presents a Bayesian networks cognitive reliability model by taking the main control room as a reference background and human factors as the key points. The model mainly analyzes the cognitive reliability affected by the human factors, and for the cognitive node and influence factors corresponding to cognitive node, a series of methods and function formulas to compute the node cognitive reliability is proposed. The model and corresponding methods can be applied to the evaluation of cognitive process for the nuclear power plant operators and have a certain significance for the prevention of safety accidents in nuclear power plants. (authors)

  10. Quantification of source impact to PM using three-dimensional weighted factor model analysis on multi-site data

    Science.gov (United States)

    Shi, Guoliang; Peng, Xing; Huangfu, Yanqi; Wang, Wei; Xu, Jiao; Tian, Yingze; Feng, Yinchang; Ivey, Cesunica E.; Russell, Armistead G.

    2017-07-01

    Source apportionment technologies are used to understand the impacts of important sources of particulate matter (PM) air quality, and are widely used for both scientific studies and air quality management. Generally, receptor models apportion speciated PM data from a single sampling site. With the development of large scale monitoring networks, PM speciation are observed at multiple sites in an urban area. For these situations, the models should account for three factors, or dimensions, of the PM, including the chemical species concentrations, sampling periods and sampling site information, suggesting the potential power of a three-dimensional source apportionment approach. However, the principle of three-dimensional Parallel Factor Analysis (Ordinary PARAFAC) model does not always work well in real environmental situations for multi-site receptor datasets. In this work, a new three-way receptor model, called "multi-site three way factor analysis" model is proposed to deal with the multi-site receptor datasets. Synthetic datasets were developed and introduced into the new model to test its performance. Average absolute error (AAE, between estimated and true contributions) for extracted sources were all less than 50%. Additionally, three-dimensional ambient datasets from a Chinese mega-city, Chengdu, were analyzed using this new model to assess the application. Four factors are extracted by the multi-site WFA3 model: secondary source have the highest contributions (64.73 and 56.24 μg/m3), followed by vehicular exhaust (30.13 and 33.60 μg/m3), crustal dust (26.12 and 29.99 μg/m3) and coal combustion (10.73 and 14.83 μg/m3). The model was also compared to PMF, with general agreement, though PMF suggested a lower crustal contribution.

  11. Pion form factor within QCD instanton vacuum model

    International Nuclear Information System (INIS)

    Dorokhov, A.E.

    1997-01-01

    Instanton induced pion wave function is constructed. It provides an intrinsic k 1 dependence which suppress soft virtual one-gluon exchanges and thus legitimate the perturbative QCD (pQCD) calculations of the pion electromagnetic form factor in the region of momentum transfers above the scale. (author)

  12. The Modeling of Factors That Influence Coast Guard Manpower Requirements

    Science.gov (United States)

    2014-12-01

    applications, and common data warehouses needed to fully develop an effective and efficient manpower requirements engineering and management program. The... manpower requirements determination ensures a ready force, and safe and effective mission execution. Shortage or excess of manpower is the catalyst...FACTORS THAT INFLUENCE COAST GUARD MANPOWER REQUIREMENTS by Kara M. Lavin December 2014 Thesis Advisor: Ronald E. Giachetti Co-Advisor

  13. On Modeling and Analyzing Cost Factors in Information Systems Engineering

    NARCIS (Netherlands)

    Mutschler, B.B.; Reichert, M.U.

    Introducing enterprise information systems (EIS) is usually associated with high costs. It is therefore crucial to understand those factors that determine or influence these costs. Though software cost estimation has received considerable attention during the last decades, it is difficult to apply

  14. A MATHEMATICAL MODEL FOR ASSESSING THE FACTORING ACTIVITY

    Directory of Open Access Journals (Sweden)

    Madalina Radoi

    2013-11-01

    Full Text Available Originally–being over 4,000 years old–factoring was first used in the fertile territory of old Mesopotamia at a time when the famous Code of Hammurabi was drawn up. However, many years passed until the British colonists started to use it on a large scale at a time when the metropolis would pay them sums of money for the merchandise that colonists sent to the old continent until they collected the invoices.In Romania factoring started to play a major role in financial operations for it led to the increase of liquidities on the market.According to the Romanian legislation, factoring is a contract concluded between a party known as “the client”, which supplies merchandise or provides services, and a banking institution or specialized financial institution known as “the factor”, whereby the latter ensures the financing source, collects the receivables and protects credit risks, while the client assigns to the factor the receivables resulting from the sale of goods or the provision of services to third parties.

  15. Meaningful Causal Model among Psycho-sociological Factors on ...

    African Journals Online (AJOL)

    Intervention programmes should be designed on the aforementioned factors so as to enhance the psychological well-being of the hearing impaired adolescents in southwest Nigeria. Keywords: Psychological well-being,, Age, Self-concept, Hearing impairment, Self-efficacy. Gender & Behaviour, 10(2), December 2012 ...

  16. Nephrogenic systemic fibrosis: risk factors suggested from Japanese published cases

    DEFF Research Database (Denmark)

    Tsushima, Y; Kanal, E; Thomsen, H S

    2010-01-01

    The aim of this article is to review the published cases of nephrogenic systemic fibrosis (NSF) in Japan. The Japanese medical literature database and MedLine were searched using the keywords NSF and nephrogenic fibrosing dermopathy (January 2000 to March 2009). Reports in peer-reviewed journals...... and meeting abstracts were included, and cases with biopsy confirmation were selected. 14 biopsy-verified NSF cases were found. In seven of eight patients reported after the association between gadolinium-based contrast agent (GBCA) and NSF was proposed, GBCA administration was documented: five received only...

  17. Nephrogenic systemic fibrosis: risk factors suggested from Japanese published cases

    DEFF Research Database (Denmark)

    Tsushima, Y; Kanal, E; Thomsen, H S

    2010-01-01

    The aim of this article is to review the published cases of nephrogenic systemic fibrosis (NSF) in Japan. The Japanese medical literature database and MedLine were searched using the keywords NSF and nephrogenic fibrosing dermopathy (January 2000 to March 2009). Reports in peer-reviewed journals ...

  18. Schistosoma mansoni reinfection: Analysis of risk factors by classification and regression tree (CART modeling.

    Directory of Open Access Journals (Sweden)

    Andréa Gazzinelli

    Full Text Available Praziquantel (PZQ is an effective chemotherapy for schistosomiasis mansoni and a mainstay for its control and potential elimination. However, it does not prevent against reinfection, which can occur rapidly in areas with active transmission. A guide to ranking the risk factors for Schistosoma mansoni reinfection would greatly contribute to prioritizing resources and focusing prevention and control measures to prevent rapid reinfection. The objective of the current study was to explore the relationship among the socioeconomic, demographic, and epidemiological factors that can influence reinfection by S. mansoni one year after successful treatment with PZQ in school-aged children in Northeastern Minas Gerais state Brazil. Parasitological, socioeconomic, demographic, and water contact information were surveyed in 506 S. mansoni-infected individuals, aged 6 to 15 years, resident in these endemic areas. Eligible individuals were treated with PZQ until they were determined to be negative by the absence of S. mansoni eggs in the feces on two consecutive days of Kato-Katz fecal thick smear. These individuals were surveyed again 12 months from the date of successful treatment with PZQ. A classification and regression tree modeling (CART was then used to explore the relationship between socioeconomic, demographic, and epidemiological variables and their reinfection status. The most important risk factor identified for S. mansoni reinfection was their "heavy" infection at baseline. Additional analyses, excluding heavy infection status, showed that lower socioeconomic status and a lower level of education of the household head were also most important risk factors for S. mansoni reinfection. Our results provide an important contribution toward the control and possible elimination of schistosomiasis by identifying three major risk factors that can be used for targeted treatment and monitoring of reinfection. We suggest that control measures that target

  19. The Five-Factor Model personality traits in schizophrenia: A meta-analysis.

    Science.gov (United States)

    Ohi, Kazutaka; Shimada, Takamitsu; Nitta, Yusuke; Kihara, Hiroaki; Okubo, Hiroaki; Uehara, Takashi; Kawasaki, Yasuhiro

    2016-06-30

    Personality is one of important factors in the pathogenesis of schizophrenia because it affects patients' symptoms, cognition and social functioning. Several studies have reported specific personality traits in patients with schizophrenia compared with healthy subjects. However, the results were inconsistent among studies. The NEO Five-Factor Inventory (NEO-FFI) measures five personality traits: Neuroticism (N), Extraversion (E), Openness (O), Agreeableness (A) and Conscientiousness (C). Here, we performed a meta-analysis of these personality traits assessed by the NEO-FFI in 460 patients with schizophrenia and 486 healthy subjects from the published literature and investigated possible associations between schizophrenia and these traits. There was no publication bias for any traits. Because we found evidence of significant heterogeneity in all traits among the studies, we applied a random-effect model to perform the meta-analysis. Patients with schizophrenia showed a higher score for N and lower scores for E, O, A and C compared with healthy subjects. The effect sizes of these personality traits ranged from moderate to large. These differences were not affected by possible moderator factors, such as gender distribution and mean age in each study, expect for gender effect for A. These findings suggest that patients with schizophrenia have a different personality profile compared with healthy subjects. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. The Influence Factor Model for the Popularity of Mobile Phone without Considering the Price Factor

    Science.gov (United States)

    Long, Hongming; Peng, Diefei; Wu, Hailin; Yang, Zihui

    2018-01-01

    Based on the statistical data like economic development, social development, population indicator and so on, this paper establishes the linear regression model which influences the popularity rate of mobile phone users.

  1. Three-dimensional models of Mycobacterium tuberculosis proteins Rv1555, Rv1554 and their docking analyses with sildenafil, tadalafil, vardenafil drugs, suggest interference with quinol binding likely to affect protein's function.

    Science.gov (United States)

    Dash, Pallabini; Bala Divya, M; Guruprasad, Lalitha; Guruprasad, Kunchur

    2018-04-18

    Earlier based on bioinformatics analyses, we had predicted the Mycobacterium tuberculosis (M.tb) proteins; Rv1555 and Rv1554, among the potential new tuberculosis drug targets. According to the 'TB-drugome' the Rv1555 protein is 'druggable' with sildenafil (Viagra), tadalafil (Cialis) and vardenafil (Levitra) drugs. In the present work, we intended to understand via computer modeling studies, how the above drugs are likely to inhibit the M.tb protein's function. The three-dimensional computer models for M.tb proteins; Rv1555 and Rv1554 constructed on the template of equivalent membrane anchor subunits of the homologous E.coli quinol fumarate reductase respiratory protein complex, followed by drug docking analyses, suggested that the binding of above drugs interferes with quinol binding sites. Also, we experimentally observed the in-vitro growth inhibition of E.coli bacteria containing the homologous M.tb protein sequences with sildenafil and tadalafil drugs. The predicted binding sites of the drugs is likely to affect the above M.tb proteins function as quinol binding is known to be essential for electron transfer function during anaerobic respiration in the homologous E.coli protein complex. Therefore, sildenafil and related drugs currently used in the treatment of male erectile dysfunction targeting the human phosphodiesterase 5 enzyme may be evaluated for their plausible role as repurposed drugs to treat human tuberculosis.

  2. Partial-factor Energy Efficiency Model of Indonesia

    OpenAIRE

    Nugroho Fathul; Syaifudin Noor

    2018-01-01

    This study employs the partial-factor energy efficiency to reveal the relationships between energy efficiency and the consumption of both, the renewable energy and non-renewable energy in Indonesia. The findings confirm that consumption of non-renewable energy will increase the inefficiency in energy consumption. On the other side, the use of renewable energy will increase the energy efficiency in Indonesia. As the result, the Government of Indonesia may address this issue by providing more s...

  3. Model of key success factors for Business Intelligence implementation

    OpenAIRE

    Peter Mesaros; Tomas Mandicak; Daniela Mackova; Stefan Carnicky; Martina Habinakova; Marcela Spisakova

    2016-01-01

    New progressive technologies recorded growth in every area. Information-communication technologies facilitate the exchange of information and it facilitates management of everyday activities in enterprises. Specific modules (such as Business Intelligence) facilitate decision-making. Several studies have demonstrated the positive impact of Business Intelligence to decision-making. The first step is to put in place the enterprise. The implementation process is influenced by many factors. This a...

  4. A New European Slope Length and Steepness Factor (LS-Factor for Modeling Soil Erosion by Water

    Directory of Open Access Journals (Sweden)

    Panos Panagos

    2015-04-01

    Full Text Available The Universal Soil Loss Equation (USLE model is the most frequently used model for soil erosion risk estimation. Among the six input layers, the combined slope length and slope angle (LS-factor has the greatest influence on soil loss at the European scale. The S-factor measures the effect of slope steepness, and the L-factor defines the impact of slope length. The combined LS-factor describes the effect of topography on soil erosion. The European Soil Data Centre (ESDAC developed a new pan-European high-resolution soil erosion assessment to achieve a better understanding of the spatial and temporal patterns of soil erosion in Europe. The LS-calculation was performed using the original equation proposed by Desmet and Govers (1996 and implemented using the System for Automated Geoscientific Analyses (SAGA, which incorporates a multiple flow algorithm and contributes to a precise estimation of flow accumulation. The LS-factor dataset was calculated using a high-resolution (25 m Digital Elevation Model (DEM for the whole European Union, resulting in an improved delineation of areas at risk of soil erosion as compared to lower-resolution datasets. This combined approach of using GIS software tools with high-resolution DEMs has been successfully applied in regional assessments in the past, and is now being applied for first time at the European scale.

  5. Transforming growth factor-β and breast cancer: Lessons learned from genetically altered mouse models

    International Nuclear Information System (INIS)

    Wakefield, Lalage M; Yang, Yu-an; Dukhanina, Oksana

    2000-01-01

    Transforming growth factor (TGF)-βs are plausible candidate tumor suppressors in the breast. They also have oncogenic activities under certain circumstances, however. Genetically altered mouse models provide powerful tools to analyze the complexities of TGF-βaction in the context of the whole animal. Overexpression of TGF-β can suppress tumorigenesis in the mammary gland, raising the possibility that use of pharmacologic agents to enhance TGF-β function locally might be an effective method for the chemoprevention of breast cancer. Conversely, loss of TGF-β response increases spontaneous and induced tumorigenesis in the mammary gland. This confirms that endogenous TGF-βs have tumor suppressor activity in the mammary gland, and suggests that the loss of TGF-β receptors seen in some human breast hyperplasias may play a causal role in tumor development

  6. Model of medicines sales forecasting taking into account factors of influence

    Science.gov (United States)

    Kravets, A. G.; Al-Gunaid, M. A.; Loshmanov, V. I.; Rasulov, S. S.; Lempert, L. B.

    2018-05-01

    The article describes a method for forecasting sales of medicines in conditions of data sampling, which is insufficient for building a model based on historical data alone. The developed method is applicable mainly to new drugs that are already licensed and released for sale but do not yet have stable sales performance in the market. The purpose of this study is to prove the effectiveness of the suggested method forecasting drug sales, taking into account the selected factors of influence, revealed during the review of existing solutions and analysis of the specificity of the area under study. Three experiments were performed on samples of different volumes, which showed an improvement in the accuracy of forecasting sales in small samples.

  7. A Five-Factor Model framework for understanding childhood personality disorder antecedents.

    Science.gov (United States)

    De Clercq, Barbara; De Fruyt, Filip

    2012-12-01

    The present contribution reviews evidence that supports the relevance of childhood antecedents of personality disorders, and advocates that the validity of a Five-Factor Model framework for describing general trait differences in childhood can be extended towards the field of developmental personality difficulties. In addition, we suggest that several traditional childhood Axis I conditions include a substantial trait component that may be responsible for the recurring finding that childhood Axis I disorders are predictive for adult Axis II disorders. Given the valuable information provided by a trait assessment, we further propose to integrate dimensional personality and personality pathology measures as standard tools in mental health assessments at a young age. © 2012 The Authors. Journal of Personality © 2012, Wiley Periodicals, Inc.

  8. Factors inducing in-stent restenosis: an in-vitro model.

    Science.gov (United States)

    Santin, M; Morris, C; Harrison, M; Mikhalovska, L; Lloyd, A W; Mikhalovsky, S

    2004-05-01

    In-stent restenosis is caused by the proliferation of the smooth muscle cells (SMCs) following a host response towards the implanted device. However, the precise biochemical and cellular mechanisms are still not completely understood. In this paper, the behaviour of SMCs has been investigated by an in vitro model where the cells were stimulated by platelet derived growth factor (PDGF) on tissue-like substrates as well as on biomaterials such as stainless steel (St) and diamond-like carbon (DLC)-coated St. The results demonstrated that SMCs have a completely different adhesion mode on St and become particularly prone to proliferation and pro-inflammatory cytokine secretion under PDGF stimulus. This would suggest that restenosis may caused by the accidental contact of the SMC with the St substrate under an inflammatory insult.

  9. Factor Structure and Market Integration under Two-Factor Monopolistic Competition Model

    Directory of Open Access Journals (Sweden)

    Evgeny Vladimirovich Zhelobodko

    2013-09-01

    Full Text Available The authors study the impact of trade liberalization on the market of a differentiated good and consumers’ welfare. The economy involves two factors of production: labor and capital. The researchers find that consumers always gain from trade liberalization. The article also establishes that the behavior of equilibrium price is independent of factor endowments’ structure in the countries involved into trade. The equilibrium price decreases (increases, remains unchanged under trade liberalization if and only if the inverse demand elasticity is increasing (decreasing, constant with respect to the individual consumption level. Furthermore, firms’ size which are measured as output increases (decreases when autarky changes to free trade if and only if the country is relatively richer (poorer in capital than its trading partner, regardless of the demand-side properties of the economy. Finally, the behavior of capital price (which equals firms’ profits in equilibrium is more complicated in the general case, but can be fully characterized for two limiting cases: (i when the structure of factor endowments in both countries is the same, and (ii when the Foreign country is a periphery country, i.e. it has zero endowment of capital

  10. Do experiments suggest a hierarchy problem?

    International Nuclear Information System (INIS)

    Vissani, F.

    1997-09-01

    The hierarchy problem of the scalar sector of the standard model is reformulated, emphasizing the role of experimental facts that may suggest the existence of a new physics large mass scale, for instance indications of the instability of the matter, or indications in favor of massive neutrinos. In the see-saw model for the neutrino masses a hierarchy problem arises if the mass of the right-handed neutrinos is larger than approximatively 10 7 GeV: this problem, and its possible solutions, are discussed. (author)

  11. Forecasting Multivariate Volatility using the VARFIMA Model on Realized Covariance Cholesky Factors

    DEFF Research Database (Denmark)

    Halbleib, Roxana; Voev, Valeri

    2011-01-01

    This paper analyzes the forecast accuracy of the multivariate realized volatility model introduced by Chiriac and Voev (2010), subject to different degrees of model parametrization and economic evaluation criteria. Bymodelling the Cholesky factors of the covariancematrices, the model generates......, regardless of the type of utility function or return distribution, would be better-off from using this model than from using some standard approaches....

  12. Modeling lichen communities : ecological key factors in a changing environment

    OpenAIRE

    Lopes, Pedro António Pinho, 1976-

    2010-01-01

    Tese de doutoramento, Biologia (Ecologia), Universidade de Lisboa, Faculdade de Ciências, 2010 O fenómeno das alterações globais influencia o funcionamento de muitos dos sistemas planetários. Embora os factores ambientais associados a esse fenómeno funcionem numa escala global, os seus efeitos nos ecossistemas têm de ser estudados localmente. Este estudo é complexo não só pela necessidade de obter informação com uma elevada resolução espacial, mas também pela dificuldade de estarmos a trab...

  13. Factors affecting GEBV accuracy with single-step Bayesian models.

    Science.gov (United States)

    Zhou, Lei; Mrode, Raphael; Zhang, Shengli; Zhang, Qin; Li, Bugao; Liu, Jian-Feng

    2018-01-01

    A single-step approach to obtain genomic prediction was first proposed in 2009. Many studies have investigated the components of GEBV accuracy in genomic selection. However, it is still unclear how the population structure and the relationships between training and validation populations influence GEBV accuracy in terms of single-step analysis. Here, we explored the components of GEBV accuracy in single-step Bayesian analysis with a simulation study. Three scenarios with various numbers of QTL (5, 50, and 500) were simulated. Three models were implemented to analyze the simulated data: single-step genomic best linear unbiased prediction (GBLUP; SSGBLUP), single-step BayesA (SS-BayesA), and single-step BayesB (SS-BayesB). According to our results, GEBV accuracy was influenced by the relationships between the training and validation populations more significantly for ungenotyped animals than for genotyped animals. SS-BayesA/BayesB showed an obvious advantage over SSGBLUP with the scenarios of 5 and 50 QTL. SS-BayesB model obtained the lowest accuracy with the 500 QTL in the simulation. SS-BayesA model was the most efficient and robust considering all QTL scenarios. Generally, both the relationships between training and validation populations and LD between markers and QTL contributed to GEBV accuracy in the single-step analysis, and the advantages of single-step Bayesian models were more apparent when the trait is controlled by fewer QTL.

  14. EcoWellness: The Missing Factor in Holistic Wellness Models

    Science.gov (United States)

    Reese, Ryan F.; Myers, Jane E.

    2012-01-01

    A growing body of multidisciplinary literature has delineated the benefits that natural environments have on physical and mental health. Current wellness models in counseling do not specifically address the impact of nature on wellness or how the natural world can be integrated into counseling. The concept of EcoWellness is presented as the…

  15. Factor Analysis of Drawings: Application to College Student Models of the Greenhouse Effect

    Science.gov (United States)

    Libarkin, Julie C.; Thomas, Stephen R.; Ording, Gabriel

    2015-01-01

    Exploratory factor analysis was used to identify models underlying drawings of the greenhouse effect made by over 200 entering university freshmen. Initial content analysis allowed deconstruction of drawings into salient features, with grouping of these features via factor analysis. A resulting 4-factor solution explains 62% of the data variance,…

  16. Loneliness and solitude in adolescence: A confirmatory factor analysis of alternative models

    DEFF Research Database (Denmark)

    Goossens, Luc; Lasgaard, Mathias; Luyckx, Koen

    2009-01-01

    completed by a sample of mid-adolescents (N = 534) from Grades 10 through 12 (aged 15-18 years) in the Dutch-speaking part of Belgium. As expected, the four-factor solution provided a better fit to the data than did alternative models that comprised just a single factor, or two and three factors. Use...

  17. Suggestion of a conventional Islamic calendar

    Directory of Open Access Journals (Sweden)

    M.G. Rashed

    2017-12-01

    Full Text Available There is a complexity of the problem concerning the first sighting of the new lunar crescent, which is attributed to various astronomical, astrophysical and geographical factors. Therefore, Astronomers adopted various criteria for the new crescent visibility. Muslims around the world differ in the beginning of the Hijric months. In fact the differences are not due to different methodology of astronomical calculations, which in turn the variations of the calendar at different countries gives. Farewell Hajj of Prophet Mohamed was on Friday, the ninth of Thul'hejja of the tenth year of immigration (Biography of the Prophet Mohamed. Therefor; the beginning of the month of Thul'hejja 10 A.H is on Thursday. Our suggested calendar takes Farewell Hajj of the Prophet Mohammad to be the base of this calendar. The advantage of our suggested calendar far away from any criteria; where the adoption of criteria for the new crescent visibility is often misleading.

  18. Suggestion of a conventional Islamic calendar

    Science.gov (United States)

    Rashed, M. G.; Moklof, M. G.

    2017-12-01

    There is a complexity of the problem concerning the first sighting of the new lunar crescent, which is attributed to various astronomical, astrophysical and geographical factors. Therefore, Astronomers adopted various criteria for the new crescent visibility. Muslims around the world differ in the beginning of the Hijric months. In fact the differences are not due to different methodology of astronomical calculations, which in turn the variations of the calendar at different countries gives. Farewell Hajj of Prophet Mohamed was on Friday, the ninth of Thul'hejja of the tenth year of immigration (Biography of the Prophet Mohamed). Therefor; the beginning of the month of Thul'hejja 10 A.H is on Thursday. Our suggested calendar takes Farewell Hajj of the Prophet Mohammad to be the base of this calendar. The advantage of our suggested calendar far away from any criteria; where the adoption of criteria for the new crescent visibility is often misleading.

  19. Using a knowledge elicitation method to specify the business model of a human factors organization

    NARCIS (Netherlands)

    Schraagen, J.M.C.; Ven, J. van de; Hoffman, R.R.; Moon, B.M.

    2009-01-01

    Concept Mapping was used to structure knowledge elicitation interviews with a group of human factors specialists whose goal was to describe the business model of their Department. This novel use of cognitive task analysis to describe the business model of a human factors organization resulted in a

  20. Using a knowledge elicitation method to specify the business model of a human factors organization.

    NARCIS (Netherlands)

    Schraagen, Johannes Martinus Cornelis; van de Ven, Josine; Hoffman, Robert R.; Moon, Brian M.

    2009-01-01

    Concept Mapping was used to structure knowledge elicitation interviews with a group of human factors specialists whose goal was to describe the business model of their Department. This novel use of cognitive task analysis to describe the business model of a human factors organization resulted in a

  1. The effects of motivational factors on car use : a multidisciplinary modelling approach

    NARCIS (Netherlands)

    Steg, L; Geurs, K; Ras, M

    Current transport models usually do not take motivational factors into account, and if they do, it is only implicitly. This paper presents a modelling approach aimed at explicitly examining the effects of motivational factors on present and future car use in the Netherlands. A car-use forecasting

  2. Generalized Efficient Inference on Factor Models with Long-Range Dependence

    DEFF Research Database (Denmark)

    Ergemen, Yunus Emre

    . Short-memory dynamics are allowed in the common factor structure and possibly heteroskedastic error term. In the estimation, a generalized version of the principal components (PC) approach is proposed to achieve efficiency. Asymptotics for efficient common factor and factor loading as well as long......A dynamic factor model is considered that contains stochastic time trends allowing for stationary and nonstationary long-range dependence. The model nests standard I(0) and I(1) behaviour smoothly in common factors and residuals, removing the necessity of a priori unit-root and stationarity testing...

  3. Confirmation of the three-factor model of problematic internet use on off-line adolescent and adult samples.

    Science.gov (United States)

    Koronczai, Beatrix; Urbán, Róbert; Kökönyei, Gyöngyi; Paksi, Borbála; Papp, Krisztina; Kun, Bernadette; Arnold, Petra; Kállai, János; Demetrovics, Zsolt

    2011-11-01

    As the Internet became widely used, problems associated with its excessive use became increasingly apparent. Although for the assessment of these problems several models and related questionnaires have been elaborated, there has been little effort made to confirm them. The aim of the present study was to test the three-factor model of the previously created Problematic Internet Use Questionnaire (PIUQ) by data collection methods formerly not applied (off-line group and face-to-face settings), on the one hand, and by testing on different age groups (adolescent and adult representative samples), on the other hand. Data were collected from 438 high-school students (44.5 percent boys; mean age: 16.0 years; standard deviation=0.7 years) and also from 963 adults (49.9 percent males; mean age: 33.6 years; standard deviation=11.8 years). We applied confirmatory factor analysis to confirm the measurement model of problematic Internet use. The results of the analyses carried out inevitably support the original three-factor model over the possible one-factor solution. Using latent profile analysis, we identified 11 percent of adults and 18 percent of adolescent users characterized by problematic use. Based on exploratory factor analysis, we also suggest a short form of the PIUQ consisting of nine items. Both the original 18-item version of PIUQ and its short 9-item form have satisfactory reliability and validity characteristics, and thus, they are suitable for the assessment of problematic Internet use in future studies.

  4. The use of the bi-factor model to test the uni-dimensionality of a battery of reasoning tests.

    Science.gov (United States)

    Primi, Ricardo; Rocha da Silva, Marjorie Cristina; Rodrigues, Priscila; Muniz, Monalisa; Almeida, Leandro S

    2013-02-01

    The Battery of Reasoning Tests 5 (BPR-5) aims to assess the reasoning ability of individuals, using sub-tests with different formats and contents that require basic processes of inductive and deductive reasoning for their resolution. The BPR has three sequential forms: BPR-5i (for children from first to fifth grade), BPR-5 - Form A (for children from sixth to eighth grade) and BPR-5 - form B (for high school and undergraduate students). The present study analysed 412 questionnaires concerning BPR-5i, 603 questionnaires concerning BPR-5 - Form A and 1748 questionnaires concerning BPR-5 - Form B. The main goal was to test the uni-dimensionality of the battery and its tests in relation to items using the bi-factor model. Results suggest that the g factor loadings (extracted by the uni-dimensional model) do not change when the data is adjusted for a more flexible multi-factor model (bi-factor model). A general reasoning factor underlying different contents items is supported.

  5. Cholesterol, Triglycerides, and the Five-Factor Model of Personality

    Science.gov (United States)

    Sutin, Angelina R.; Terracciano, Antonio; Deiana, Barbara; Uda, Manuela; Schlessinger, David; Lakatta, Edward G.; Costa, Paul T.

    2010-01-01

    Unhealthy lipid levels are among the leading controllable risk factors for coronary heart disease. To identify the psychological factors associated with dyslipidemia, this study investigates the personality correlates of cholesterol (total, LDL, and HDL) and triglycerides. A community-based sample (N=5,532) from Sardinia, Italy, had their cholesterol and triglyceride levels assessed and completed a comprehensive personality questionnaire, the NEO-PI-R. All analyses controlled for age, sex, BMI, smoking, drinking, hypertension, and diabetes. Low Conscientiousness and traits related to impulsivity were associated with lower HDL cholesterol and higher triglycerides. Compared to the lowest 10%, those who scored in top 10% on Impulsivity had a 2.5 times greater risk of exceeding the clinical threshold for elevated triglycerides (OR=2.51, CI=1.56–4.07). In addition, sex moderated the association between trait depression (a component of Neuroticism) and HDL cholesterol, such that trait depression was associated with lower levels of HDL cholesterol in women but not men. When considering the connection between personality and health, unhealthy lipid profiles may be one intermediate biomarker between personality and morbidity and mortality. PMID:20109519

  6. Perceived stress latent factors and the burnout subtypes: a structural model in dental students.

    Science.gov (United States)

    Montero-Marín, Jesús; Piva Demarzo, Marcelo Marcos; Stapinski, Lexine; Gili, Margarita; García-Campayo, Javier

    2014-01-01

    Students of health-professions suffer high levels of stress and burnout. The aim of the present study was to evaluate the relationship between perceived stress latent factors ('tenseness' and 'frustration') and the features ('overload', 'lack of development' and 'neglect') of the three burnout subtypes ('frenetic', 'under-challenged' and 'worn-out', respectively), in a sample of Spanish dental students. The study employed a cross-sectional design. A sample of Spanish dental students (n = 314) completed the 'Perceived Stress Questionnaire' and the 'Burnout Clinical Subtype Questionnaire Student Survey'. The associations among variables were observed by means of structural equation modelling using the unweighted least squares method from polychoric correlations. Strong associations among perceived stress factors and the burnout characteristics were observed, although a distinct pattern of relations was observed for each burnout subtype. The 'overload' was moderately and positively associated with both 'tenseness' (0.45), and 'frustration' (0.38) dimensions of perceived stress; the 'lack of development' was positively associated with the 'frustration' dimension (0.72), but negatively associated with 'tenseness' (-0.69); the 'neglect' showed a weaker positive associated with 'frustration' (0.41), and a small negative association with 'tenseness' (-0.20). The model was a very good fit to the data (GFI  =  0.96; RSMR  =  0.07; AGFI = 0.96; NFI = 0.95; RFI = 0.95). The stress factors of 'frustration' and 'tenseness' seems to be related in a distinct way to the burnout subtypes in Spanish dental students. This finding suggests that intervention programs specifically tailored to these subtypes may be a promising future direction.

  7. Perceived stress latent factors and the burnout subtypes: a structural model in dental students.

    Directory of Open Access Journals (Sweden)

    Jesús Montero-Marín

    Full Text Available Students of health-professions suffer high levels of stress and burnout. The aim of the present study was to evaluate the relationship between perceived stress latent factors ('tenseness' and 'frustration' and the features ('overload', 'lack of development' and 'neglect' of the three burnout subtypes ('frenetic', 'under-challenged' and 'worn-out', respectively, in a sample of Spanish dental students.The study employed a cross-sectional design. A sample of Spanish dental students (n = 314 completed the 'Perceived Stress Questionnaire' and the 'Burnout Clinical Subtype Questionnaire Student Survey'. The associations among variables were observed by means of structural equation modelling using the unweighted least squares method from polychoric correlations.Strong associations among perceived stress factors and the burnout characteristics were observed, although a distinct pattern of relations was observed for each burnout subtype. The 'overload' was moderately and positively associated with both 'tenseness' (0.45, and 'frustration' (0.38 dimensions of perceived stress; the 'lack of development' was positively associated with the 'frustration' dimension (0.72, but negatively associated with 'tenseness' (-0.69; the 'neglect' showed a weaker positive associated with 'frustration' (0.41, and a small negative association with 'tenseness' (-0.20. The model was a very good fit to the data (GFI  =  0.96; RSMR  =  0.07; AGFI = 0.96; NFI = 0.95; RFI = 0.95.The stress factors of 'frustration' and 'tenseness' seems to be related in a distinct way to the burnout subtypes in Spanish dental students. This finding suggests that intervention programs specifically tailored to these subtypes may be a promising future direction.

  8. Impulsivity, self-control, and hypnotic suggestibility.

    Science.gov (United States)

    Ludwig, V U; Stelzel, C; Krutiak, H; Prunkl, C E; Steimke, R; Paschke, L M; Kathmann, N; Walter, H

    2013-06-01

    Hypnotic responding might be due to attenuated frontal lobe functioning after the hypnotic induction. Little is known about whether personality traits linked with frontal functioning are associated with responsiveness to hypnotic suggestions. We assessed whether hypnotic suggestibility is related to the traits of self-control and impulsivity in 154 participants who completed the Brief Self-Control Scale, the Self-Regulation Scale, the Barratt Impulsiveness Scale (BIS-11), and the Harvard Group Scale of Hypnotic Susceptibility (HGSHS:A). BIS-11 non-planning impulsivity correlated positively with HGSHS:A (Bonferroni-corrected). Furthermore, in the best model emerging from a stepwise multiple regression, both non-planning impulsivity and self-control positively predicted hypnotic suggestibility, and there was an interaction of BIS-11 motor impulsivity with gender. For men only, motor impulsivity tended to predict hypnotic suggestibility. Hypnotic suggestibility is associated with personality traits linked with frontal functioning, and hypnotic responding in men and women might differ. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Separating form factor and nuclear model effects in quasielastic neutrino-nucleus scattering

    Science.gov (United States)

    Wieske, Joseph

    2017-09-01

    When studying neutrino oscillations an understanding of charged current quasielastic (CCQE) neutrino-nucleus scattering is imperative. This interaction depends on a nuclear model as well as knowledge of form factors. In the past, CCQE data from the MiniBooNE experiment was analyzed assuming the Relativistic Fermi Gas (RFG) nuclear model, an axial dipole form factor in, and using the the z-expansion for the axial form factor in. We present the first analysis that combines a non-RFG nuclear model, in particular the Correlated Fermi Gas nuclear model (CFG) of, and the z expansion for the axial form factor. This will allow us to separate form factor and nuclear model effects in CCQE scattering. This project was supported through the Wayne State University REU program under NSF Grant PHY-1460853 and by the DOE Grant DE-SC0007983.

  10. A Two-Factor Autoregressive Moving Average Model Based on Fuzzy Fluctuation Logical Relationships

    Directory of Open Access Journals (Sweden)

    Shuang Guan

    2017-10-01

    Full Text Available Many of the existing autoregressive moving average (ARMA forecast models are based on one main factor. In this paper, we proposed a new two-factor first-order ARMA forecast model based on fuzzy fluctuation logical relationships of both a main factor and a secondary factor of a historical training time series. Firstly, we generated a fluctuation time series (FTS for two factors by calculating the difference of each data point with its previous day, then finding the absolute means of the two FTSs. We then constructed a fuzzy fluctuation time series (FFTS according to the defined linguistic sets. The next step was establishing fuzzy fluctuation logical relation groups (FFLRGs for a two-factor first-order autoregressive (AR(1 model and forecasting the training data with the AR(1 model. Then we built FFLRGs for a two-factor first-order autoregressive moving average (ARMA(1,m model. Lastly, we forecasted test data with the ARMA(1,m model. To illustrate the performance of our model, we used real Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX and Dow Jones datasets as a secondary factor to forecast TAIEX. The experiment results indicate that the proposed two-factor fluctuation ARMA method outperformed the one-factor method based on real historic data. The secondary factor may have some effects on the main factor and thereby impact the forecasting results. Using fuzzified fluctuations rather than fuzzified real data could avoid the influence of extreme values in historic data, which performs negatively while forecasting. To verify the accuracy and effectiveness of the model, we also employed our method to forecast the Shanghai Stock Exchange Composite Index (SHSECI from 2001 to 2015 and the international gold price from 2000 to 2010.

  11. Scrub Typhus Incidence Modeling with Meteorological Factors in South Korea.

    Science.gov (United States)

    Kwak, Jaewon; Kim, Soojun; Kim, Gilho; Singh, Vijay P; Hong, Seungjin; Kim, Hung Soo

    2015-06-29

    Since its recurrence in 1986, scrub typhus has been occurring annually and it is considered as one of the most prevalent diseases in Korea. Scrub typhus is a 3rd grade nationally notifiable disease that has greatly increased in Korea since 2000. The objective of this study is to construct a disease incidence model for prediction and quantification of the incidences of scrub typhus. Using data from 2001 to 2010, the incidence Artificial Neural Network (ANN) model, which considers the time-lag between scrub typhus and minimum temperature, precipitation and average wind speed based on the Granger causality and spectral analysis, is constructed and tested for 2011 to 2012. Results show reliable simulation of scrub typhus incidences with selected predictors, and indicate that the seasonality in meteorological data should be considered.

  12. Scrub Typhus Incidence Modeling with Meteorological Factors in South Korea

    Directory of Open Access Journals (Sweden)

    Jaewon Kwak

    2015-06-01

    Full Text Available Since its recurrence in 1986, scrub typhus has been occurring annually and it is considered as one of the most prevalent diseases in Korea. Scrub typhus is a 3rd grade nationally notifiable disease that has greatly increased in Korea since 2000. The objective of this study is to construct a disease incidence model for prediction and quantification of the incidences of scrub typhus. Using data from 2001 to 2010, the incidence Artificial Neural Network (ANN model, which considers the time-lag between scrub typhus and minimum temperature, precipitation and average wind speed based on the Granger causality and spectral analysis, is constructed and tested for 2011 to 2012. Results show reliable simulation of scrub typhus incidences with selected predictors, and indicate that the seasonality in meteorological data should be considered.

  13. Literature Review and Assessment of Plant and Animal Transfer Factors Used in Performance Assessment Modeling

    International Nuclear Information System (INIS)

    Robertson, David E.; Cataldo, Dominic A.; Napier, Bruce A.; Krupka, Kenneth M.; Sasser, Lyle B.

    2003-01-01

    A literature review and assessment was conducted by Pacific Northwest National Laboratory (PNNL) to update information on plant and animal radionuclide transfer factors used in performance-assessment modeling. A group of 15 radionuclides was included in this review and assessment. The review is composed of four main sections, not including the Introduction. Section 2.0 provides a review of the critically important issue of physicochemical speciation and geochemistry of the radionuclides in natural soil-water systems as it relates to the bioavailability of the radionuclides. Section 3.0 provides an updated review of the parameters of importance in the uptake of radionuclides by plants, including root uptake via the soil-groundwater system and foliar uptake due to overhead irrigation. Section 3.0 also provides a compilation of concentration ratios (CRs) for soil-to-plant uptake for the 15 selected radionuclides. Section 4.0 provides an updated review on radionuclide uptake data for animal products related to absorption, homeostatic control, approach to equilibration, chemical and physical form, diet, and age. Compiled transfer coefficients are provided for cow's milk, sheep's milk, goat's milk, beef, goat meat, pork, poultry, and eggs. Section 5.0 discusses the use of transfer coefficients in soil, plant, and animal modeling using regulatory models for evaluating radioactive waste disposal or decommissioned sites. Each section makes specific suggestions for future research in its area.

  14. Literature Review and Assessment of Plant and Animal Transfer Factors Used in Performance Assessment Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, David E.; Cataldo, Dominic A.; Napier, Bruce A.; Krupka, Kenneth M.; Sasser, Lyle B.

    2003-07-20

    A literature review and assessment was conducted by Pacific Northwest National Laboratory (PNNL) to update information on plant and animal radionuclide transfer factors used in performance-assessment modeling. A group of 15 radionuclides was included in this review and assessment. The review is composed of four main sections, not including the Introduction. Section 2.0 provides a review of the critically important issue of physicochemical speciation and geochemistry of the radionuclides in natural soil-water systems as it relates to the bioavailability of the radionuclides. Section 3.0 provides an updated review of the parameters of importance in the uptake of radionuclides by plants, including root uptake via the soil-groundwater system and foliar uptake due to overhead irrigation. Section 3.0 also provides a compilation of concentration ratios (CRs) for soil-to-plant uptake for the 15 selected radionuclides. Section 4.0 provides an updated review on radionuclide uptake data for animal products related to absorption, homeostatic control, approach to equilibration, chemical and physical form, diet, and age. Compiled transfer coefficients are provided for cow’s milk, sheep’s milk, goat’s milk, beef, goat meat, pork, poultry, and eggs. Section 5.0 discusses the use of transfer coefficients in soil, plant, and animal modeling using regulatory models for evaluating radioactive waste disposal or decommissioned sites. Each section makes specific suggestions for future research in its area.

  15. Factoring variations in natural images with deep Gaussian mixture models

    OpenAIRE

    van den Oord, Aäron; Schrauwen, Benjamin

    2014-01-01

    Generative models can be seen as the swiss army knives of machine learning, as many problems can be written probabilistically in terms of the distribution of the data, including prediction, reconstruction, imputation and simulation. One of the most promising directions for unsupervised learning may lie in Deep Learning methods, given their success in supervised learning. However, one of the cur- rent problems with deep unsupervised learning methods, is that they often are harder to scale. As ...

  16. Scale Factor Study for 1:30 Local Scour Model

    Science.gov (United States)

    2016-08-01

    establishes the worst- case scour depth for the current bridge configuration and the proposed pier nose extension. INTRODUCTION : Extensive research has been...used in the general physical model. A flat test section, approximately 32 ft long and 34–45 ft wide, was molded to a uniform elevation . Stilling...discharge calculation from the flow uniformity checks. The water surface elevation was controlled with the adjustable lift gate at the downstream

  17. Dynamic structure factor for liquid He4 and quantum lattice model

    International Nuclear Information System (INIS)

    Lee, M.H.

    1975-01-01

    It has been realized for some time now that the quantum lattice model (or the anisotropic Heisenberg antiferromagnetic model) is a useful model for studying the properties of quantum liquids especially near the lambda transition. The static critical values calculated from the quantum lattice model are in good agreement with the observed values. Furthermore, it was shown recently that there are collective modes in the quantum lattice model which are equivalent to the plasmons. Hence, it would seem to be interesting to study the dynamic structure factor for the quantum lattice model and to make a comparison with experiment. Work on the dynamic structure factor is reported here. (Auth.)

  18. Reciprocal burnout model: Interconnectedness of interpersonal and intrapersonal factors

    Directory of Open Access Journals (Sweden)

    Andreja Pšeničny

    2007-01-01

    Full Text Available Burnout can be described as chronic state of extreme psychophysical and emotional exhaustion. Burning out is a stage process consisting of: the stage of exhaustion, the stage of captivity and the final stage – adrenal burnout. Adrenal burnout syndrome (ABS is the final stage of burning out process, resulting in a functional blocade of hypothalamic-pituitary-adrenal axis which causes secondary cortisol insufficiency. Even though they share similar symptoms, burnout and depression are two different types of disorder. They differ mainly in basic cortisol levels and self-esteem. Researchers tend to link the burnout syndrome and environmental stress (interpersonal causes. Recently, some of them found connection between burnout syndrome and personality traits (intrapersonal causes. Reciprocal burnout model links both causes. It shows that in the same circumstances only a few people suffer from adrenal burnout syndrome. It states that personal characteristics are one of the main causes why people suffering from burnout syndrome enroll in nonreciprocal personal and professional relations. Socialization process plays an important role in development of personality traits. The core of the reciprocal burnout model consists of one's attitude towards his or her basic needs' fulfillment, personal system of values, and correlation between fulfillment of basic needs (energy accumulation and burning out process (energy consumption. Reciprocal burnout model is opening a series of questions, concerning the connection between personality traits, life satisfaction and personal values, and burnout syndrome risk behavior, as well as the influence of whole life circumstances on burning out process.

  19. A structural dynamic factor model for the effects of monetary policy estimated by the EM algorithm

    DEFF Research Database (Denmark)

    Bork, Lasse

    This paper applies the maximum likelihood based EM algorithm to a large-dimensional factor analysis of US monetary policy. Specifically, economy-wide effects of shocks to the US federal funds rate are estimated in a structural dynamic factor model in which 100+ US macroeconomic and financial time...... series are driven by the joint dynamics of the federal funds rate and a few correlated dynamic factors. This paper contains a number of methodological contributions to the existing literature on data-rich monetary policy analysis. Firstly, the identification scheme allows for correlated factor dynamics...... as opposed to the orthogonal factors resulting from the popular principal component approach to structural factor models. Correlated factors are economically more sensible and important for a richer monetary policy transmission mechanism. Secondly, I consider both static factor loadings as well as dynamic...

  20. Pipeline for Efficient Mapping of Transcription Factor Binding Sites and Comparison of Their Models

    KAUST Repository

    Ba alawi, Wail

    2011-06-01

    The control of genes in every living organism is based on activities of transcription factor (TF) proteins. These TFs interact with DNA by binding to the TF binding sites (TFBSs) and in that way create conditions for the genes to activate. Of the approximately 1500 TFs in human, TFBSs are experimentally derived only for less than 300 TFs and only in generally limited portions of the genome. To be able to associate TF to genes they control we need to know if TFs will have a potential to interact with the control region of the gene. For this we need to have models of TFBS families. The existing models are not sufficiently accurate or they are too complex for use by ordinary biologists. To remove some of the deficiencies of these models, in this study we developed a pipeline through which we achieved the following: 1. Through a comparison analysis of the performance we identified the best models with optimized thresholds among the four different types of models of TFBS families. 2. Using the best models we mapped TFBSs to the human genome in an efficient way. The study shows that a new scoring function used with TFBS models based on the position weight matrix of dinucleotides with remote dependency results in better accuracy than the other three types of the TFBS models. The speed of mapping has been improved by developing a parallelized code and shows a significant speed up of 4x when going from 1 CPU to 8 CPUs. To verify if the predicted TFBSs are more accurate than what can be expected with the conventional models, we identified the most frequent pairs of TFBSs (for TFs E4F1 and ATF6) that appeared close to each other (within the distance of 200 nucleotides) over the human genome. We show unexpectedly that the genes that are most close to the multiple pairs of E4F1/ATF6 binding sites have a co-expression of over 90%. This indirectly supports our hypothesis that the TFBS models we use are more accurate and also suggests that the E4F1/ATF6 pair is exerting the

  1. Multinomial Response Models, for Modeling and Determining Important Factors in Different Contraceptive Methods in Women

    Directory of Open Access Journals (Sweden)

    E Haji Nejad

    2001-06-01

    Full Text Available Difference aspects of multinomial statistical modelings and its classifications has been studied so far. In these type of problems Y is the qualitative random variable with T possible states which are considered as classifications. The goal is prediction of Y based on a random Vector X ? IR^m. Many methods for analyzing these problems were considered. One of the modern and general method of classification is Classification and Regression Trees (CART. Another method is recursive partitioning techniques which has a strange relationship with nonparametric regression. Classical discriminant analysis is a standard method for analyzing these type of data. Flexible discriminant analysis method which is a combination of nonparametric regression and discriminant analysis and classification using spline that includes least square regression and additive cubic splines. Neural network is an advanced statistical method for analyzing these types of data. In this paper properties of multinomial logistics regression were investigated and this method was used for modeling effective factors in selecting contraceptive methods in Ghom province for married women age 15-49. The response variable has a tetranomial distibution. The levels of this variable are: nothing, pills, traditional and a collection of other contraceptive methods. A collection of significant independent variables were: place, age of women, education, history of pregnancy and family size. Menstruation age and age at marriage were not statistically significant.

  2. Does Sluggish Cognitive Tempo Fit within a Bi-factor Model of Attention-Deficit/Hyperactivity Disorder?

    Science.gov (United States)

    Garner, Annie A.; Peugh, James; Becker, Stephen P.; Kingery, Kathleen M.; Tamm, Leanne; Vaughn, Aaron J.; Ciesielski, Heather; Simon, John O.; Loren, Richard E. A.; Epstein, Jeffery N.

    2014-01-01

    Objective Studies demonstrate sluggish cognitive tempo (SCT) symptoms to be distinct from inattentive and hyperactive-impulsive dimensions of Attention-Deficit/Hyperactivity Disorder (ADHD). No study has examined SCT within a bi-factor model of ADHD whereby SCT may form a specific factor distinct from inattention and hyperactivity/impulsivity while still fitting within a general ADHD factor, which was the purpose of the current study. Method 168 children were recruited from an ADHD clinic. Most (92%) met diagnostic criteria for ADHD. Parents and teachers completed measures of ADHD and SCT. Results Although SCT symptoms were strongly associated with inattention they loaded onto a factor independent of ADHD ‘g’. Results were consistent across parent and teacher ratings. Conclusions SCT is structurally distinct from inattention as well as from the general ADHD latent symptom structure. Findings support a growing body of research suggesting SCT to be distinct and separate from ADHD. PMID:25005039

  3. Collapsing Factors in Multitrait-Multimethod Models: Examining Consequences of a Mismatch Between Measurement Design and Model

    Directory of Open Access Journals (Sweden)

    Christian eGeiser

    2015-08-01

    Full Text Available Models of confirmatory factor analysis (CFA are frequently applied to examine the convergent validity of scores obtained from multiple raters or methods in so-called multitrait-multimethod (MTMM investigations. Many applications of CFA-MTMM and similarly structured models result in solutions in which at least one method (or specific factor shows non-significant loading or variance estimates. Eid et al. (2008 distinguished between MTMM measurement designs with interchangeable (randomly selected versus structurally different (fixed methods and showed that each type of measurement design implies specific CFA-MTMM measurement models. In the current study, we hypothesized that some of the problems that are commonly seen in applications of CFA-MTMM models may be due to a mismatch between the underlying measurement design and fitted models. Using simulations, we found that models with M method factors (where M is the total number of methods and unconstrained loadings led to a higher proportion of solutions in which at least one method factor became empirically unstable when these models were fit to data generated from structurally different methods. The simulations also revealed that commonly used model goodness-of-fit criteria frequently failed to identify incorrectly specified CFA-MTMM models. We discuss implications of these findings for other complex CFA models in which similar issues occur, including nested (bifactor and latent state-trait models.

  4. Factoring vs linear modeling in rate estimation: a simulation study of relative accuracy.

    Science.gov (United States)

    Maldonado, G; Greenland, S

    1998-07-01

    A common strategy for modeling dose-response in epidemiology is to transform ordered exposures and covariates into sets of dichotomous indicator variables (that is, to factor the variables). Factoring tends to increase estimation variance, but it also tends to decrease bias and thus may increase or decrease total accuracy. We conducted a simulation study to examine the impact of factoring on the accuracy of rate estimation. Factored and unfactored Poisson regression models were fit to follow-up study datasets that were randomly generated from 37,500 population model forms that ranged from subadditive to supramultiplicative. In the situations we examined, factoring sometimes substantially improved accuracy relative to fitting the corresponding unfactored model, sometimes substantially decreased accuracy, and sometimes made little difference. The difference in accuracy between factored and unfactored models depended in a complicated fashion on the difference between the true and fitted model forms, the strength of exposure and covariate effects in the population, and the study size. It may be difficult in practice to predict when factoring is increasing or decreasing accuracy. We recommend, therefore, that the strategy of factoring variables be supplemented with other strategies for modeling dose-response.

  5. Predisposing, precipitating and perpetuating factors and the common sense model of illness

    DEFF Research Database (Denmark)

    Carstensen, Tina; Kasch, Helge; Frostholm, Lisbeth

    2017-01-01

    Background: Various predisposing, precipitating and perpetuating factors are found to be associated with development of persistent symptoms and disability after whiplash trauma. According to the commonsense model of illness, people use commonsense knowledge to develop individual illness models when...... facing health threat. Question: Can we use the common-sense model as a unifying model to encompass the impact of predisposing, precipitating, and perpetuating factors in the development of chronic whiplash? Looking into specific factors and their interaction: Do illness perceptions mediate the effect...... of precollision sick leave on chronic whiplash? Methods: This presentation will integrate findings from research on predisposing, precipitating, perpetuating factors that are associated with poor outcome after whiplash trauma and propose the common-sense model as a unifying model. Data from a study including 740...

  6. Non-linear models for the relation between cardiovascular risk factors and intake of wine, beer and spirits.

    Science.gov (United States)

    Ambler, Gareth; Royston, Patrick; Head, Jenny

    2003-02-15

    It is generally accepted that moderate consumption of alcohol is associated with a reduced risk of coronary heart disease (CHD). It is not clear however whether this benefit is derived through the consumption of a specific beverage type, for example, wine. In this paper the associations between known CHD risk factors and different beverage types are investigated using a novel approach with non-linear modelling. Two types of model are proposed which are designed to detect differential effects of beverage type. These may be viewed as extensions of Box and Tidwell's power-linear model. The risk factors high density lipoprotein cholesterol, fibrinogen and systolic blood pressure are considered using data from a large longitudinal study of British civil servants (Whitehall II). The results for males suggest that gram for gram of alcohol, the effect of wine differs from that of beer and spirits, particularly for systolic blood pressure. In particular increasing wine consumption is associated with slightly more favourable levels of all three risk factors studied. For females there is evidence of a differential relationship only for systolic blood pressure. These findings are tentative but suggest that further research is required to clarify the similarities and differences between the results for males and females and to establish whether either of the models is the more appropriate. However, having clarified these issues, the apparent benefit of consuming wine instead of other alcoholic beverages may be relatively small. Copyright 2003 John Wiley & Sons, Ltd.

  7. Determination of osteoporosis risk factors using a multiple logistic regression model in postmenopausal Turkish women.

    Science.gov (United States)

    Akkus, Zeki; Camdeviren, Handan; Celik, Fatma; Gur, Ali; Nas, Kemal

    2005-09-01

    To determine the risk factors of osteoporosis using a multiple binary logistic regression method and to assess the risk variables for osteoporosis, which is a major and growing health problem in many countries. We presented a case-control study, consisting of 126 postmenopausal healthy women as control group and 225 postmenopausal osteoporotic women as the case group. The study was carried out in the Department of Physical Medicine and Rehabilitation, Dicle University, Diyarbakir, Turkey between 1999-2002. The data from the 351 participants were collected using a standard questionnaire that contains 43 variables. A multiple logistic regression model was then used to evaluate the data and to find the best regression model. We classified 80.1% (281/351) of the participants using the regression model. Furthermore, the specificity value of the model was 67% (84/126) of the control group while the sensitivity value was 88% (197/225) of the case group. We found the distribution of residual values standardized for final model to be exponential using the Kolmogorow-Smirnow test (p=0.193). The receiver operating characteristic curve was found successful to predict patients with risk for osteoporosis. This study suggests that low levels of dietary calcium intake, physical activity, education, and longer duration of menopause are independent predictors of the risk of low bone density in our population. Adequate dietary calcium intake in combination with maintaining a daily physical activity, increasing educational level, decreasing birth rate, and duration of breast-feeding may contribute to healthy bones and play a role in practical prevention of osteoporosis in Southeast Anatolia. In addition, the findings of the present study indicate that the use of multivariate statistical method as a multiple logistic regression in osteoporosis, which maybe influenced by many variables, is better than univariate statistical evaluation.

  8. Further insights on the French WISC-IV factor structure through Bayesian structural equation modeling.

    Science.gov (United States)

    Golay, Philippe; Reverte, Isabelle; Rossier, Jérôme; Favez, Nicolas; Lecerf, Thierry

    2013-06-01

    The interpretation of the Wechsler Intelligence Scale for Children--Fourth Edition (WISC-IV) is based on a 4-factor model, which is only partially compatible with the mainstream Cattell-Horn-Carroll (CHC) model of intelligence measurement. The structure of cognitive batteries is frequently analyzed via exploratory factor analysis and/or confirmatory factor analysis. With classical confirmatory factor analysis, almost all cross-loadings between latent variables and measures are fixed to zero in order to allow the model to be identified. However, inappropriate zero cross-loadings can contribute to poor model fit, distorted factors, and biased factor correlations; most important, they do not necessarily faithfully reflect theory. To deal with these methodological and theoretical limitations, we used a new statistical approach, Bayesian structural equation modeling (BSEM), among a sample of 249 French-speaking Swiss children (8-12 years). With BSEM, zero-fixed cross-loadings between latent variables and measures are replaced by approximate zeros, based on informative, small-variance priors. Results indicated that a direct hierarchical CHC-based model with 5 factors plus a general intelligence factor better represented the structure of the WISC-IV than did the 4-factor structure and the higher order models. Because a direct hierarchical CHC model was more adequate, it was concluded that the general factor should be considered as a breadth rather than a superordinate factor. Because it was possible for us to estimate the influence of each of the latent variables on the 15 subtest scores, BSEM allowed improvement of the understanding of the structure of intelligence tests and the clinical interpretation of the subtest scores. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  9. A Key Factor of the DCF Model Coherency

    Directory of Open Access Journals (Sweden)

    Piotr Adamczyk

    2017-04-01

    Full Text Available Aim/purpose - The aim of this paper is to provide economically justified evidence that the business value calculated by income valuation methods is the same, regardless of the type of cash flow used in the valuation algorithm. Design/methodology/approach - The evidence was arrived at using free cash flow to equity (FCFE, debt (FCFD and firm (FCFF. The article draws attention to the FCFF method's particular popularity in income valuation, based on analysts' practice. It shows an overview of various approaches to determine the capital structure in the formula for WACC, both in practice and theory. Finally, it examines an empirical example with the authors' own derivations and postulates. Findings - The conclusion drawn from the conducted analysis is that the key to the reconciliation process, and thus DCF model coherency, is to apply the appropriate method of capital structure estimation during the calculation of the weighted average cost of capital (WACC. This capital structure will henceforth be referred to as 'income weights'. Research implications/limitations - It should be noted that the obtained compliance of valuation results does not imply that the income valuation becomes an objective way of determining business value. It still remains subjective. Originality/value/contribution - According to the presented approach, the DCF model's subjectivism is limited to the forecasts. The rest is the algorithm which, based on the principles of mathematics, should be used in the same way in every situation.

  10. Prediction of human pharmacokinetics of activated recombinant factor VII and B-domain truncated factor VIII from animal population pharmacokinetic models of haemophilia

    DEFF Research Database (Denmark)

    Larsen, Malte Selch; Juul, Rasmus Vestergaard; Groth, Andreas Velsing

    2018-01-01

    activated factor VII (rFVIIa) and recombinant factor VIII (rFVIII) in several experimental animal models using population PK modelling, and apply a simulation-based approach to evaluate how well the developed animal population PK models predict human PK. PK models were developed for rFVIIa and r...

  11. Aspect-Aware Latent Factor Model: Rating Prediction with Ratings and Reviews

    OpenAIRE

    Cheng, Zhiyong; Ding, Ying; Zhu, Lei; Kankanhalli, Mohan

    2018-01-01

    Although latent factor models (e.g., matrix factorization) achieve good accuracy in rating prediction, they suffer from several problems including cold-start, non-transparency, and suboptimal recommendation for local users or items. In this paper, we employ textual review information with ratings to tackle these limitations. Firstly, we apply a proposed aspect-aware topic model (ATM) on the review text to model user preferences and item features from different aspects, and estimate the aspect...

  12. Trichotillomania and personality traits from the five-factor model

    Directory of Open Access Journals (Sweden)

    Nancy J. Keuthen

    2015-01-01

    Full Text Available Objective:To examine whether personality traits have predictive validity for trichotillomania (TTM diagnosis, pulling severity and control, and hair pulling style.Methods:In study 1, logistic regression was used with TTM cases (n=54 and controls (n=25 to determine if NEO Five-Factor Inventory (NEO-FFI personality domains predicted TTM case vs. control classification. In study 2, hierarchical multiple regression was used with TTM cases (n=164 to determine whether NEO-FFI personality domains predicted hair pulling severity and control as well as focused and automatic pulling styles.Results:TTM case vs. control status was predicted by NEO-FFI neuroticism. Every 1-point increase in neuroticism scores resulted in a 10% greater chance of TTM diagnosis. Higher neuroticism, higher openness, and lower agreeableness were associated with greater pulling severity. Higher neuroticism was also associated with less control over hair pulling. Higher neuroticism and lower openness were associated with greater focused pulling. None of the personality domains predicted automatic hair pulling.Conclusions:Personality traits, especially neuroticism, can predict TTM diagnosis, hair pulling severity and control, and the focused style of pulling. None of the personality traits predicted automatic pulling. Longitudinal studies are needed to determine whether personality variables predispose to TTM onset, impact disorder course, and/or result from hair pulling behavior.

  13. New JLS-Factor Model versus the Standard JLS Model: A Case Study on Chinese Stock Bubbles

    Directory of Open Access Journals (Sweden)

    Zongyi Hu

    2017-01-01

    Full Text Available In this paper, we extend the Johansen-Ledoit-Sornette (JLS model by introducing fundamental economic factors in China (including the interest rate and deposit reserve rate and the historical volatilities of targeted and US equity indices into the original model, which is a flexible tool to detect bubbles and predict regime changes in financial markets. We then derive a general method to incorporate these selected factors in addition to the log-periodic power law signature of herding and compare the prediction accuracy of the critical time between the original and the new JLS models (termed the JLS-factor model by applying these two models to fit two well-known Chinese stock indices in three bubble periods. The results show that the JLS-factor model with Chinese characteristics successfully depicts the evolutions of bubbles and “antibubbles” and constructs efficient end-of-bubble signals for all bubbles in Chinese stock markets. In addition, the results of standard statistical tests demonstrate the excellent explanatory power of these additive factors and confirm that the new JLS model provides useful improvements over the standard JLS model.

  14. Modeling the Factors Impacting Pesticide Concentrations in Groundwater Wells

    DEFF Research Database (Denmark)

    Aisopou, Angeliki; Binning, Philip John; Albrechtsen, Hans-Jørgen

    2015-01-01

    This study examines the effect of pumping, hydrogeology, and pesticide characteristics on pesticide concentrations in production wells using a reactive transport model in two conceptual hydrogeologic systems; a layered aquifer with and without a stream present. The pumping rate can significantly...... affect the pesticide breakthrough time and maximum concentration at the well. The effect of the pumping rate on the pesticide concentration depends on the hydrogeology of the aquifer; in a layered aquifer, a high pumping rate resulted in a considerably different breakthrough than a low pumping rate......, while in an aquifer with a stream the effect of the pumping rate was insignificant. Pesticide application history and properties have also a great impact on the effect of the pumping rate on the concentration at the well. The findings of the study show that variable pumping rates can generate temporal...

  15. Role of tissue factor and protease-activated receptors in a mouse model of endotoxemia.

    Science.gov (United States)

    Pawlinski, Rafal; Pedersen, Brian; Schabbauer, Gernot; Tencati, Michael; Holscher, Todd; Boisvert, William; Andrade-Gordon, Patricia; Frank, Rolf Dario; Mackman, Nigel

    2004-02-15

    Sepsis is associated with a systemic activation of coagulation and an excessive inflammatory response. Anticoagulants have been shown to inhibit both coagulation and inflammation in sepsis. In this study, we used both genetic and pharmacologic approaches to analyze the role of tissue factor and protease-activated receptors in coagulation and inflammation in a mouse endotoxemia model. We used mice expressing low levels of the procoagulant molecule, tissue factor (TF), to analyze the effects of TF deficiency either in all tissues or selectively in hematopoietic cells. Low TF mice had reduced coagulation, inflammation, and mortality compared with control mice. Similarly, a deficiency of TF expression by hematopoietic cells reduced lipopolysaccharide (LPS)-induced coagulation, inflammation, and mortality. Inhibition of the down-stream coagulation protease, thrombin, reduced fibrin deposition and prolonged survival without affecting inflammation. Deficiency of either protease activated receptor-1 (PAR-1) or protease activated receptor-2 (PAR-2) alone did not affect inflammation or survival. However, a combination of thrombin inhibition and PAR-2 deficiency reduced inflammation and mortality. These data demonstrate that hematopoietic cells are the major pathologic site of TF expression during endotoxemia and suggest that multiple protease-activated receptors mediate crosstalk between coagulation and inflammation.

  16. A Study on Influencing Factors of Knowledge Management Systems Adoption: Models Comparison Approach

    OpenAIRE

    Mei-Chun Yeh; Ming-Shu Yuan

    2007-01-01

    Using Linear Structural Relation model (LISREL model) as analysis method and technology acceptance model and decomposed theory of planned behavior as research foundation, this study approachesmainly from the angle of behavioral intention to examine the influential factors of 421 employees adopting knowledge management systems and in the meantime to compare the two method models mentioned on the top. According to the research, there is no, in comparison with technology acceptance model anddeco...

  17. Skyrme-model πNN form factor and nucleon-nucleon interaction

    International Nuclear Information System (INIS)

    Holzwarth, G.; Machleidt, R.

    1997-01-01

    We apply the strong πNN form factor, which emerges from the Skyrme model, in the two-nucleon system using a one-boson-exchange (OBE) model for the nucleon-nucleon (NN) interaction. Deuteron properties and phase parameters of NN scattering are reproduced well. In contrast to the form factor of monopole shape that is traditionally used in OBE models, the Skyrme form factor leaves low-momentum transfers essentially unaffected while it suppresses the high-momentum region strongly. It turns out that this behavior is very appropriate for models of the NN interaction and makes it possible to use a soft pion form factor in the NN system. As a consequence, the πN and the NN systems can be described using the same πNN form factor, which is impossible with the monopole. copyright 1997 The American Physical Society

  18. FEM effective suggestion of guitar construction

    Directory of Open Access Journals (Sweden)

    Vladimír Dániel

    2006-01-01

    Full Text Available Modal analysis of the whole guitar construction was performed. The results of eigenfrequencies were obtained. Stress in strings affects not only static loading of material, but also shift of eigenfrequencies. From obtained natural frequencies for solved spectrum such frequencies were used which coincides with assumed ribs new positions of ribs were suggested. Other ribs which do not carry out the mechanical function were removed. Also static reaction was evaluated and new position of ribs was adjusted. For final model new eigenfrequencies were computed and compared with previous ones. Significant changes were revealed in low frequencies (bellow 400 Hz where fewer amounts of natural shapes were obtained. Approximately 50% were lost by adding of ribs. For chosen frequencies of equal temperament the harmonic analysis was performed. The analysis proved ability of oscillation for frequencies far of natural frequencies. The final model satisfies the requirement of minimization of static stress in material due to strings and allows very effective oscillation of top the guitar resonance board. In comparison with literature good agreement in amplitude size of front board and amount of modes in appropriate frequencies were achieved. Suggested model even offers higher amount of natural shapes in comparison with literature, namely in high frequencies. From additional comparison of eigenfrequencies and natural shapes the influence of ribs position on natural shapes was approved.

  19. Factors influencing the occupational injuries of physical therapists in Taiwan: A hierarchical linear model approach.

    Science.gov (United States)

    Tao, Yu-Hui; Wu, Yu-Lung; Huang, Wan-Yun

    2017-01-01

    The evidence literature suggests that physical therapy practitioners are subjected to a high probability of acquiring work-related injuries, but only a few studies have specifically investigated Taiwanese physical therapy practitioners. This study was conducted to determine the relationships among individual and group hospital-level factors that contribute to the medical expenses for the occupational injuries of physical therapy practitioners in Taiwan. Physical therapy practitioners in Taiwan with occupational injuries were selected from the 2013 National Health Insurance Research Databases (NHIRD). The age, gender, job title, hospitals attributes, and outpatient data of physical therapy practitioners who sustained an occupational injury in 2013 were obtained with SAS 9.3. SPSS 20.0 and HLM 7.01 were used to conduct descriptive and hierarchical linear model analyses, respectively. The job title of physical therapy practitioners at the individual level and the hospital type at the group level exert positive effects on per person medical expenses. Hospital hierarchy moderates the individual-level relationships of age and job title with the per person medical expenses. Considering that age, job title, and hospital hierarchy affect medical expenses for the occupational injuries of physical therapy practitioners, we suggest strengthening related safety education and training and elevating the self-awareness of the risk of occupational injuries of physical therapy practitioners to reduce and prevent the occurrence of such injuries.

  20. Support vector regression model for the estimation of γ-ray buildup factors for multi-layer shields

    International Nuclear Information System (INIS)

    Trontl, Kresimir; Smuc, Tomislav; Pevec, Dubravko

    2007-01-01

    The accuracy of the point-kernel method, which is a widely used practical tool for γ-ray shielding calculations, strongly depends on the quality and accuracy of buildup factors used in the calculations. Although, buildup factors for single-layer shields comprised of a single material are well known, calculation of buildup factors for stratified shields, each layer comprised of different material or a combination of materials, represent a complex physical problem. Recently, a new compact mathematical model for multi-layer shield buildup factor representation has been suggested for embedding into point-kernel codes thus replacing traditionally generated complex mathematical expressions. The new regression model is based on support vector machines learning technique, which is an extension of Statistical Learning Theory. The paper gives complete description of the novel methodology with results pertaining to realistic engineering multi-layer shielding geometries. The results based on support vector regression machine learning confirm that this approach provides a framework for general, accurate and computationally acceptable multi-layer buildup factor model

  1. Behavioral phenotypes in schizophrenic animal models with multiple combinations of genetic and environmental factors.

    Science.gov (United States)

    Hida, Hirotake; Mouri, Akihiro; Noda, Yukihiro

    2013-01-01

    Schizophrenia is a multifactorial psychiatric disorder in which both genetic and environmental factors play a role. Genetic [e.g., Disrupted-in-schizophrenia 1 (DISC1), Neuregulin-1 (NRG1)] and environmental factors (e.g., maternal viral infection, obstetric complications, social stress) may act during the developmental period to increase the incidence of schizophrenia. In animal models, interactions between susceptibility genes and the environment can be controlled in ways not possible in humans; therefore, such models are useful for investigating interactions between or within factors in the pathogenesis and pathophysiology of schizophrenia. We provide an overview of schizophrenic animal models investigating interactions between or within factors. First, we reviewed gene-environment interaction animal models, in which schizophrenic candidate gene mutant mice were subjected to perinatal immune activation or adolescent stress. Next, environment-environment interaction animal models, in which mice were subjected to a combination of perinatal immune activation and adolescent administration of drugs, were described. These animal models showed interaction between or within factors; behavioral changes, which were obscured by each factor, were marked by interaction of factors and vice versa. Appropriate behavioral approaches with such models will be invaluable for translational research on novel compounds, and also for providing insight into the pathogenesis and pathophysiology of schizophrenia.

  2. A model of gender prejudice, power, and discrimination: How hierarchy-enhancing factors predominate over hierarchy-attenuating factors

    OpenAIRE

    Kleinlogel, E. P.; Dietz, J.

    2015-01-01

    Gender inequalities remain an issue in our society and particularly in the workplace. Several factors can explain this gender difference in top-level managerial positions such as career ambitions but also biases against women. In our chapter, we propose a model explaining why gender inequalities and particularly discrimination against women is still present in our societies despite social norms and existing legislation on gender equality. To this purpose, we review research on discrimination ...

  3. The effects of motivational factors on car use: a multidisciplinary modelling approach

    Energy Technology Data Exchange (ETDEWEB)

    Steg, L.; Ras, M. [University of Groningen (Netherlands). Centre for Environmental and Traffic Psychology; Geurs, K. [National Institute of Public Health and Environment, Bilthoven (Netherlands)

    2001-11-01

    Current transport models usually do not take motivational factors into account, and if they do, it is only implicitly. This paper presents a modelling approach aimed at explicitly examining the effects of motivational factors on present and future car use in the Netherlands. A car-use forecasting model for the years 2010 and 2020 was constructed on the basis of (i) a multinominal regression analysis, which revealed the importance of a motivational variable (viz., problem awareness) in explaining current car-use behavior separate from socio-demographic and socio-economic variables, and (ii) a population model constructed to forecast the size and composition of the Dutch population. The results show that car use could be better explained by taking motivational factors explicitly into account, and that the level of car use forecast might change significantly if changes in motivations are assumed. The question on how motivational factors could be incorporated into current (Dutch) national transport models was also addressed. (author)

  4. Modeling the factors affecting unsafe behavior in the construction industry from safety supervisors' perspective.

    Science.gov (United States)

    Khosravi, Yahya; Asilian-Mahabadi, Hassan; Hajizadeh, Ebrahim; Hassanzadeh-Rangi, Narmin; Bastani, Hamid; Khavanin, Ali; Mortazavi, Seyed Bagher

    2014-01-01

    There can be little doubt that the construction is the most hazardous industry in the worldwide. This study was designed to modeling the factors affecting unsafe behavior from the perspective of safety supervisors. The qualitative research was conducted to extract a conceptual model. A structural model was then developed based on a questionnaire survey (n=266) by two stage Structural Equation Model (SEM) approach. An excellent confirmed 12-factors structure explained about 62% of variances unsafe behavior in the construction industry. A good fit structural model indicated that safety climate factors were positively correlated with safety individual factors (Pconstruction workers' engagement in safe or unsafe behavior. In order to improve construction safety performance, more focus on the workplace condition is required.

  5. Factors Models of Scrum Adoption in the Software Development Process: A Systematic Literature Review

    Directory of Open Access Journals (Sweden)

    Marilyn Sihuay

    2018-05-01

    Full Text Available (Background The adoption of Agile Software Development (ASD, in particular Scrum, has grown significantly since its introduction in 2001. However, in Lima, many ASDs implementations have been not suitable (uncompleted or inconsistent, thus losing benefits obtainable by this approach and the critical success factors in this context are unknown. (Objective To analyze factors models used in the evaluation of the adoption of ASDs, as these factors models can contribute to explaining the success or failure of these adoptions. (Method In this study we used a systematic literature review. (Result Ten models have been identified; their similarities and differences are presented. (Conclusion Each model identified consider different factors, however some of them are shared by five of these models, such as team member attributes, engaging customer, customer collaboration, experience and work environment.

  6. Particle size - An important factor in environmental consequence modeling

    International Nuclear Information System (INIS)

    Yuan, Y.C.; MacFarlane, D.

    1991-01-01

    Most available environmental transport and dosimetry codes for radiological consequence analysis are designed primarily for estimating dose and health consequences to specific off-site individuals as well as the population as a whole from nuclear facilities operating under either normal or accident conditions. Models developed for these types of analyses are generally based on assumptions that the receptors are at great distances (several kilometers), and the releases are prolonged and filtered. This allows the use of simplified approaches such as averaged meteorological conditions and the use of a single (small) particle size for atmospheric transport and dosimetry analysis. Source depletion from particle settling, settle-out, and deposition is often ignored. This paper estimates the effects of large particles on the resulting dose consequences from an atmospheric release. The computer program AI-RISK has been developed to perform multiparticle-sized atmospheric transport, dose, and pathway analyses for estimating potential human health consequences from the accidental release of radioactive materials. The program was originally developed to facilitate comprehensive analyses of health consequences, ground contamination, and cleanup associated with possible energetic chemical reactions in high-level radioactive waste (HLW) tanks at a US Department of Energy site

  7. The HEXACO and Five-Factor Models of Personality in Relation to RIASEC Vocational Interests

    Science.gov (United States)

    McKay, Derek A.; Tokar, David M.

    2012-01-01

    The current study extended the empirical research on the overlap of vocational interests and personality by (a) testing hypothesized relations between RIASEC interests and the personality dimensions of the HEXACO model, and (b) exploring the HEXACO personality model's predictive advantage over the five-factor model (FFM) in capturing RIASEC…

  8. The Multi-state Latent Factor Intensity Model for Credit Rating Transitions

    NARCIS (Netherlands)

    Koopman, S.J.; Lucas, A.; Monteiro, A.

    2008-01-01

    A new empirical reduced-form model for credit rating transitions is introduced. It is a parametric intensity-based duration model with multiple states and driven by exogenous covariates and latent dynamic factors. The model has a generalized semi-Markov structure designed to accommodate many of the

  9. WALS estimation and forecasting in factor-based dynamic models with an application to Armenia

    NARCIS (Netherlands)

    Poghosyan, K.; Magnus, J.R.

    2012-01-01

    Two model averaging approaches are used and compared in estimating and forecasting dynamic factor models, the well-known Bayesian model averaging (BMA) and the recently developed weighted average least squares (WALS). Both methods propose to combine frequentist estimators using Bayesian weights. We

  10. Critical Factors Analysis for Offshore Software Development Success by Structural Equation Modeling

    Science.gov (United States)

    Wada, Yoshihisa; Tsuji, Hiroshi

    In order to analyze the success/failure factors in offshore software development service by the structural equation modeling, this paper proposes to follow two approaches together; domain knowledge based heuristic analysis and factor analysis based rational analysis. The former works for generating and verifying of hypothesis to find factors and causalities. The latter works for verifying factors introduced by theory to build the model without heuristics. Following the proposed combined approaches for the responses from skilled project managers of the questionnaire, this paper found that the vendor property has high causality for the success compared to software property and project property.

  11. Modelling of Safety Factors in the Design of GRP Composite Products

    DEFF Research Database (Denmark)

    Babu, B.J.C.; Prabhakaran, R.T. Durai; Lystrup, Aage

    2010-01-01

    as independent, while in real applications these factors may interact/influence each other. Following the concept developed by the authors, a simple graph theoretic model has been used to determine overall factor of safety. This is described with the help of an example and it has been demonstrated......An attempt has been made in this paper to arrive at the safety factor design of glass fibre reinforced polymer (GRP) composite products using graph theoretic model. In the conventional design and recommendations of the standards, these design factors affecting properties have been considered...

  12. A factor analysis of Functional Independence and Functional Assessment Measure scores among focal and diffuse brain injury patients: The importance of bi-factor models.

    Science.gov (United States)

    Gunn, Sarah; Burgess, Gerald H; Maltby, John

    2018-04-28

    To explore the factor structure of the UK Functional Independence Measure and Functional Assessment Measure (FIM+FAM) among focal and diffuse acquired brain injury patients. Criterion standard. An NHS acute acquired brain injury inpatient rehabilitation hospital. Referred sample of 447 adults (835 cases after exclusions) admitted for inpatient treatment following an acquired brain injury significant enough to justify intensive inpatient neurorehabilitation. Not applicable. Functional Independence Measure and Functional Assessment Measure. Exploratory Factor Analysis suggested a two-factor structure to FIM+FAM scores, among both focal-proximate and diffuse-proximate acquired brain injury aetiologies. Confirmatory Factor Analysis suggested a three-factor bi-factor structure presented the best fit of the FIM+FAM score data across both aetiologies. However, across both analyses, a convergence was found towards a general factor, demonstrated by high correlations between factors in the Exploratory Factor Analysis, and by a general factor explaining the majority of the variance in scores on Confirmatory Factor Analysis. Our findings suggested that although factors describing specific functional domains can be derived from FIM+FAM item scores, there is a convergence towards a single factor describing overall functioning. This single factor informs the specific group factors (e.g. motor, psychosocial and communication function) following brain injury. Further research into the comparative value of the general and group factors as evaluative/prognostic measures is indicated. Copyright © 2018. Published by Elsevier Inc.

  13. Brief report: Bifactor modeling of general vs. specific factors of religiousness differentially predicting substance use risk in adolescence.

    Science.gov (United States)

    Kim-Spoon, Jungmeen; Longo, Gregory S; Holmes, Christopher J

    2015-08-01

    Religiousness is important to adolescents in the U.S., and the significant link between high religiousness and low substance use is well known. There is a debate between multidimensional and unidimensional perspectives of religiousness (Gorsuch, 1984); yet, no empirical study has tested this hierarchical model of religiousness related to adolescent health outcomes. The current study presents the first attempt to test a bifactor model of religiousness related to substance use among adolescents (N = 220, 45% female). Our bifactor model using structural equation modeling suggested the multidimensional nature of religiousness as well as the presence of a superordinate general religiousness factor directly explaining the covariation among the specific factors including organizational and personal religiousness and religious social support. The general religiousness factor was inversely related to substance use. After accounting for the contribution of the general religiousness factor, high organizational religiousness related to low substance use, whereas personal religiousness and religious support were positively related to substance use. The findings present the first evidence that supports hierarchical structures of adolescent religiousness that contribute differentially to adolescent substance use. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  14. [Psychosocial factors at work and cardiovascular diseases: contribution of the Effort-Reward Imbalance model].

    Science.gov (United States)

    Niedhammer, I; Siegrist, J

    1998-11-01

    The effect of psychosocial factors at work on health, especially cardiovascular health, has given rise to growing concern in occupational epidemiology over the last few years. Two theoretical models, Karasek's model and the Effort-Reward Imbalance model, have been developed to evaluate psychosocial factors at work within specific conceptual frameworks in an attempt to take into account the serious methodological difficulties inherent in the evaluation of such factors. Karasek's model, the most widely used model, measures three factors: psychological demands, decision latitude and social support at work. Many studies have shown the predictive effects of these factors on cardiovascular diseases independently of well-known cardiovascular risk factors. More recently, the Effort-Reward Imbalance model takes into account the role of individual coping characteristics which was neglected in the Karasek model. The effort-reward imbalance model focuses on the reciprocity of exchange in occupational life where high-cost/low-gain conditions are considered particularly stressful. Three dimensions of rewards are distinguished: money, esteem and gratifications in terms of promotion prospects and job security. Some studies already support that high-effort/low reward-conditions are predictive of cardiovascular diseases.

  15. Modeling water quality in an urban river using hydrological factors--data driven approaches.

    Science.gov (United States)

    Chang, Fi-John; Tsai, Yu-Hsuan; Chen, Pin-An; Coynel, Alexandra; Vachaud, Georges

    2015-03-15

    Contrasting seasonal variations occur in river flow and water quality as a result of short duration, severe intensity storms and typhoons in Taiwan. Sudden changes in river flow caused by impending extreme events may impose serious degradation on river water quality and fateful impacts on ecosystems. Water quality is measured in a monthly/quarterly scale, and therefore an estimation of water quality in a daily scale would be of good help for timely river pollution management. This study proposes a systematic analysis scheme (SAS) to assess the spatio-temporal interrelation of water quality in an urban river and construct water quality estimation models using two static and one dynamic artificial neural networks (ANNs) coupled with the Gamma test (GT) based on water quality, hydrological and economic data. The Dahan River basin in Taiwan is the study area. Ammonia nitrogen (NH3-N) is considered as the representative parameter, a correlative indicator in judging the contamination level over the study. Key factors the most closely related to the representative parameter (NH3-N) are extracted by the Gamma test for modeling NH3-N concentration, and as a result, four hydrological factors (discharge, days w/o discharge, water temperature and rainfall) are identified as model inputs. The modeling results demonstrate that the nonlinear autoregressive with exogenous input (NARX) network furnished with recurrent connections can accurately estimate NH3-N concentration with a very high coefficient of efficiency value (0.926) and a low RMSE value (0.386 mg/l). Besides, the NARX network can suitably catch peak values that mainly occur in dry periods (September-April in the study area), which is particularly important to water pollution treatment. The proposed SAS suggests a promising approach to reliably modeling the spatio-temporal NH3-N concentration based solely on hydrological data, without using water quality sampling data. It is worth noticing that such estimation can be

  16. On form factors of the conjugated field in the non-linear Schroedinger model

    Energy Technology Data Exchange (ETDEWEB)

    Kozlowski, K.K.

    2011-05-15

    Izergin-Korepin's lattice discretization of the non-linear Schroedinger model along with Oota's inverse problem provides one with determinant representations for the form factors of the lattice discretized conjugated field operator. We prove that these form factors converge, in the zero lattice spacing limit, to those of the conjugated field operator in the continuous model. We also compute the large-volume asymptotic behavior of such form factors in the continuous model. These are in particular characterized by Fredholm determinants of operators acting on closed contours. We provide a way of defining these Fredholm determinants in the case of generic paramaters. (orig.)

  17. Global combustion sources of organic aerosols: model comparison with 84 AMS factor-analysis data sets

    Science.gov (United States)

    Tsimpidi, Alexandra P.; Karydis, Vlassis A.; Pandis, Spyros N.; Lelieveld, Jos

    2016-07-01

    Emissions of organic compounds from biomass, biofuel, and fossil fuel combustion strongly influence the global atmospheric aerosol load. Some of the organics are directly released as primary organic aerosol (POA). Most are emitted in the gas phase and undergo chemical transformations (i.e., oxidation by hydroxyl radical) and form secondary organic aerosol (SOA). In this work we use the global chemistry climate model ECHAM/MESSy Atmospheric Chemistry (EMAC) with a computationally efficient module for the description of organic aerosol (OA) composition and evolution in the atmosphere (ORACLE). The tropospheric burden of open biomass and anthropogenic (fossil and biofuel) combustion particles is estimated to be 0.59 and 0.63 Tg, respectively, accounting for about 30 and 32 % of the total tropospheric OA load. About 30 % of the open biomass burning and 10 % of the anthropogenic combustion aerosols originate from direct particle emissions, whereas the rest is formed in the atmosphere. A comprehensive data set of aerosol mass spectrometer (AMS) measurements along with factor-analysis results from 84 field campaigns across the Northern Hemisphere are used to evaluate the model results. Both the AMS observations and the model results suggest that over urban areas both POA (25-40 %) and SOA (60-75 %) contribute substantially to the overall OA mass, whereas further downwind and in rural areas the POA concentrations decrease substantially and SOA dominates (80-85 %). EMAC does a reasonable job in reproducing POA and SOA levels during most of the year. However, it tends to underpredict POA and SOA concentrations during winter indicating that the model misses wintertime sources of OA (e.g., residential biofuel use) and SOA formation pathways (e.g., multiphase oxidation).

  18. Self-phosphorylation of epidermal growth factor receptor: evidence for a model of intermolecular allosteric activation

    International Nuclear Information System (INIS)

    Yarden, Y.; Schlessinger, J.

    1987-01-01

    The membrane receptor for epidermal growth factor (EGF) is a 170,000 dalton glycoprotein composed of an extracellular EGF-binding domain and a cytoplasmic kinase domain connected by a stretch of 23 amino acids traversing the plasma membrane. The binding of EGF to the extracellular domain activates the cytoplasmic kinase function even in highly purified preparations of EGF receptor, suggesting that the activation occurs exclusively within the EGF receptor moiety. Conceivably, kinase activation may require the transfer of a conformational change through the single transmembrane region from the ligand binding domain to the cytoplasmic kinase region. Alternatively, ligand-induced receptor-receptor interactions may activate the kinase and thus bypass this requirement. Both mechanisms were contrasted by employing independent experimental approaches. On the basis of these results, an allosteric aggregation model is formulated for the activation of the cytoplasmic kinase function of the receptor by EGF. This model may be relevant to the mechanism by which the mitogenic signal of EGF is transferred across the membrane

  19. Morningness-eveningness, sex, and the Alternative Five Factor Model of personality.

    Science.gov (United States)

    Muro, Anna; Gomà-i-Freixanet, Montserrat; Adan, Ana

    2009-08-01

    Recent research on personality and circadian typology indicates that evening-type subjects are more extraverted, impulsive, and novelty-seeking, while morning ones tend to be more introverted, conscientious, agreeable, and emotionally stable. The purpose of this study was to examine the differences between circadian typologies on the Zuckerman's Alternative Five Factor Model of personality (AFFM), which has a strong biological basis, controlling for sex and age. A sample of 533 university students (168 men) participated in the study. Results showed that morning-type subjects had significant higher scores than evening-type and neither-type subjects in Activity, and in its subscales General Activity and Work Activity. A significant interaction between circadian typology and sex was found for Neuroticism-Anxiety: morning-type men showed higher scores than evening-type and neither-type, who had the lowest scores. Women presented the opposite pattern: neither-type obtained the highest scores, while morning-type showed the lowest. This is the first time the AFFM has been used in the context of circadian rhythms research. The results suggest that activity is the only trait related to extraversion associated with morningness, while Neuroticism-Anxiety was modulated by sex. These results might help highlight previous results on the association between morningness-eveningness and other models of personality assessment, and they offer new data that calls for further research.

  20. Angiogenic factor imbalance precedes complement deposition in placentae of the BPH/5 model of preeclampsia.

    Science.gov (United States)

    Sones, Jennifer L; Merriam, Audrey A; Seffens, Angelina; Brown-Grant, Dex-Ann; Butler, Scott D; Zhao, Anna M; Xu, Xinjing; Shawber, Carrie J; Grenier, Jennifer K; Douglas, Nataki C

    2018-05-01

    Preeclampsia (PE), a hypertensive disorder of pregnancy, is a leading cause of maternal and fetal morbidity and mortality. Although the etiology is unknown, PE is thought to be caused by defective implantation and decidualization in pregnancy. Pregnant blood pressure high (BPH)/5 mice spontaneously develop placentopathies and maternal features of human PE. We hypothesized that BPH/5 implantation sites have transcriptomic alterations. Next-generation RNA sequencing of implantation sites at peak decidualization, embryonic day (E)7.5, revealed complement gene up-regulation in BPH/5 vs. controls. In BPH/5, expression of complement factor 3 was increased around the decidual vasculature of E7.5 implantation sites and in the trophoblast giant cell layer of E10.5 placentae. Altered expression of VEGF pathway genes in E5.5 BPH/5 implantation sites preceded complement dysregulation, which correlated with abnormal vasculature and increased placental growth factor mRNA and VEGF 164 expression at E7.5. By E10.5, proangiogenic genes were down-regulated, whereas antiangiogenic sFlt-1 was up-regulated in BPH/5 placentae. We found that early local misexpression of VEGF genes and abnormal decidual vasculature preceded sFlt-1 overexpression and increased complement deposition in BPH/5 placentae. Our findings suggest that abnormal decidual angiogenesis precedes complement activation, which in turn contributes to the aberrant trophoblast invasion and poor placentation that underlie PE.-Sones, J. L., Merriam, A. A., Seffens, A., Brown-Grant, D.-A., Butler, S. D., Zhao, A. M., Xu, X., Shawber, C. J., Grenier, J. K., Douglas, N. C. Angiogenic factor imbalance precedes complement deposition in placentae of the BPH/5 model of preeclampsia.

  1. [Advance in researches on vegetation cover and management factor in the soil erosion prediction model].

    Science.gov (United States)

    Zhang, Yan; Yuan, Jianping; Liu, Baoyuan

    2002-08-01

    Vegetation cover and land management are the main limiting factors of soil erosion, and quantitative evaluation on the effect of different vegetation on soil erosion is essential to land use and soil conservation planning. The vegetation cover and management factor (C) in the universal soil loss equation (USLE) is an index to evaluate this effect, which has been studied deeply and used widely. However, the C factor study is insufficient in China. In order to strengthen the research of C factor, this paper reviewed the developing progress of C factor, and compared the methods of estimating C value in different USLE versions. The relative studies in China were also summarized from the aspects of vegetation canopy coverage, soil surface cover, and root density. Three problems in C factor study were pointed out. The authors suggested that cropland C factor research should be furthered, and its methodology should be unified in China to represent reliable C values for soil loss prediction and conservation planning.

  2. TEST OF THE FAMA-FRENCH THREE-FACTOR MODEL IN CROATIA

    Directory of Open Access Journals (Sweden)

    Denis Dolinar

    2013-06-01

    Full Text Available This paper empirically examines the Fama-French three-factor model of stock returns for Croatia. In contrast to the results of Fama and French (1993 for the U.S. stock market, their three-factor model did not show so successful when describing risk-return relation of Croatian stocks. This paper shows that the Fama-French three-factor model is a valid pricing model, since it explains cross-section of average returns on stocks in Croatia, and that has a greater explanatory power in comparison to the CAPM. In the case of Croatian stock market, size and B/M factors are not always significant, but on average they individually have certain marginal explanatory power. Namely, they capture small common variation in returns that is missed by the market factor. Moreover, B/M factor has shown as a stronger common risk proxy in relation to size factor. Finally, there is still a large portion of common variation in stock return that may be explained by other factors. Because emerging capital markets bear their own specificity, special care needs to be taken when applying existing or developing new pricing models.

  3. Measured and modeled humidification factors of fresh smoke particles from biomass burning: role of inorganic constituents

    Directory of Open Access Journals (Sweden)

    J. L. Hand

    2010-07-01

    Full Text Available During the 2006 FLAME study (Fire Laboratory at Missoula Experiment, laboratory burns of biomass fuels were performed to investigate the physico-chemical, optical, and hygroscopic properties of fresh biomass smoke. As part of the experiment, two nephelometers simultaneously measured dry and humidified light scattering coefficients (bsp(dry and bsp(RH, respectively in order to explore the role of relative humidity (RH on the optical properties of biomass smoke aerosols. Results from burns of several biomass fuels from the west and southeast United States showed large variability in the humidification factor (f(RH=bsp(RH/bsp(dry. Values of f(RH at RH=80–85% ranged from 0.99 to 1.81 depending on fuel type. We incorporated measured chemical composition and size distribution data to model the smoke hygroscopic growth to investigate the role of inorganic compounds on water uptake for these aerosols. By assuming only inorganic constituents were hygroscopic, we were able to model the water uptake within experimental uncertainty, suggesting that inorganic species were responsible for most of the hygroscopic growth. In addition, humidification factors at 80–85% RH increased for smoke with increasing inorganic salt to carbon ratios. Particle morphology as observed from scanning electron microscopy revealed that samples of hygroscopic particles contained soot chains either internally or externally mixed with inorganic potassium salts, while samples of weak to non-hygroscopic particles were dominated by soot and organic constituents. This study provides further understanding of the compounds responsible for water uptake by young biomass smoke, and is important for accurately assessing the role of smoke in climate change studies and visibility regulatory efforts.

  4. Expanding the Andersen model: the role of psychosocial factors in long-term care use.

    Science.gov (United States)

    Bradley, Elizabeth H; McGraw, Sarah A; Curry, Leslie; Buckser, Alison; King, Kinda L; Kasl, Stanislav V; Andersen, Ronald

    2002-10-01

    To examine a prevailing conceptual model of health services use (Andersen 1995) and to suggest modifications that may enhance its explanatory power when applied to empirical studies of race/ethnicity and long-term care. Twelve focus groups of African-American (five groups) and white (seven groups) individuals, aged 65 and older, residing in Connecticut during 2000. Using qualitative analysis, data were coded and analyzed in NUD-IST 4 software to facilitate the reporting of recurrent themes, supporting quotations, and links among the themes for developing the conceptual framework. Specific analysis was conducted to assess distinctions in common themes between African-American and white focus groups. Data were collected using a standardized discussion guide, augmented by prompts for clarification. Audio taped sessions were transcribed and independently coded by investigators and crosschecked to enhance coding validity. An audit trail was maintained to document analytic decisions during data analysis and interpretation. Psychosocial factors (e.g., attitudes and knowledge, social norms, and perceived control) are identified as determinants of service use, thereby expanding the Andersen model (1995). African-American and white focus group members differed in their reported accessibility of information about long-term care, social norms concerning caregiving expectations and burden, and concerns of privacy and self-determination. More comprehensive identification of psychosocial factors may enhance our understanding of the complex role of race/ethnicity in long-term care use as well as the effectiveness of policies and programs designed to address disparities in long-term care service use among minority and nonminority groups.

  5. Macroeconomic factors and oil futures prices. A data-rich model

    International Nuclear Information System (INIS)

    Zagaglia, Paolo

    2010-01-01

    I study the dynamics of oil futures prices in the NYMEX using a large panel dataset that includes global macroeconomic indicators, financial market indices, quantities and prices of energy products. I extract common factors from the panel data series and estimate a Factor-Augmented Vector Autoregression for the maturity structure of oil futures prices. I find that latent factors generate information that, once combined with that of the yields, improves the forecasting performance for oil prices. Furthermore, I show that a factor correlated to purely financial developments contributes to the model performance, in addition to factors related to energy quantities and prices. (author)

  6. Analysis on trust influencing factors and trust model from multiple perspectives of online Auction

    Science.gov (United States)

    Yu, Wang

    2017-10-01

    Current reputation models lack the research on online auction trading completely so they cannot entirely reflect the reputation status of users and may cause problems on operability. To evaluate the user trust in online auction correctly, a trust computing model based on multiple influencing factors is established. It aims at overcoming the efficiency of current trust computing methods and the limitations of traditional theoretical trust models. The improved model comprehensively considers the trust degree evaluation factors of three types of participants according to different participation modes of online auctioneers, to improve the accuracy, effectiveness and robustness of the trust degree. The experiments test the efficiency and the performance of our model under different scale of malicious user, under environment like eBay and Sporas model. The experimental results analysis show the model proposed in this paper makes up the deficiency of existing model and it also has better feasibility.

  7. Children's Memory for Their Mother's Murder: Accuracy, Suggestibility, and Resistance to Suggestion.

    Science.gov (United States)

    McWilliams, Kelly; Narr, Rachel; Goodman, Gail S; Ruiz, Sandra; Mendoza, Macaria

    2013-01-31

    From its inception, child eyewitness memory research has been guided by dramatic legal cases that turn on the testimony of children. Decades of scientific research reveal that, under many conditions, children can provide veracious accounts of traumatic experiences. Scientific studies also document factors that lead children to make false statements. In this paper we describe a legal case in which children testified about their mother's murder. We discuss factors that may have influenced the accuracy of the children's eyewitness memory. Children's suggestibility and resistance to suggestion are illustrated. Expert testimony, based on scientific research, can aid the trier of fact when children provide crucial evidence in criminal investigations and courtroom trials about tragic events.

  8. Deconstructing Constructivism: Modeling Causal Relationships Among Constructivist Learning Environment Factors and Student Outcomes in Introductory Chemistry

    Science.gov (United States)

    Komperda, Regis

    The purpose of this dissertation is to test a model of relationships among factors characterizing aspects of a student-centered constructivist learning environment and student outcomes of satisfaction and academic achievement in introductory undergraduate chemistry courses. Constructivism was chosen as the theoretical foundation for this research because of its widespread use in chemical education research and practice. In a constructivist learning environment the role of the teacher shifts from delivering content towards facilitating active student engagement in activities that encourage individual knowledge construction through discussion and application of content. Constructivist approaches to teaching introductory chemistry courses have been adopted by some instructors as a way to improve student outcomes, but little research has been done on the causal relationships among particular aspects of the learning environment and student outcomes. This makes it difficult for classroom teachers to know which aspects of a constructivist teaching approach are critical to adopt and which may be modified to better suit a particular learning environment while still improving student outcomes. To investigate a model of these relationships, a survey designed to measure student perceptions of three factors characterizing a constructivist learning environment in online courses was adapted for use in face-to-face chemistry courses. These three factors, teaching presence, social presence, and cognitive presence, were measured using a slightly modified version of the Community of Inquiry (CoI) instrument. The student outcomes investigated in this research were satisfaction and academic achievement, as measured by standardized American Chemical Society (ACS) exam scores and course grades. Structural equation modeling (SEM) was used to statistically model relationships among the three presence factors and student outcome variables for 391 students enrolled in six sections of a

  9. Cerebrolysin modulates pronerve growth factor/nerve growth factor ratio and ameliorates the cholinergic deficit in a transgenic model of Alzheimer's disease.

    Science.gov (United States)

    Ubhi, Kiren; Rockenstein, Edward; Vazquez-Roque, Ruben; Mante, Michael; Inglis, Chandra; Patrick, Christina; Adame, Anthony; Fahnestock, Margaret; Doppler, Edith; Novak, Philip; Moessler, Herbert; Masliah, Eliezer

    2013-02-01

    Alzheimer's disease (AD) is characterized by degeneration of neocortex, limbic system, and basal forebrain, accompanied by accumulation of amyloid-β and tangle formation. Cerebrolysin (CBL), a peptide mixture with neurotrophic-like effects, is reported to improve cognition and activities of daily living in patients with AD. Likewise, CBL reduces synaptic and behavioral deficits in transgenic (tg) mice overexpressing the human amyloid precursor protein (hAPP). The neuroprotective effects of CBL may involve multiple mechanisms, including signaling regulation, control of APP metabolism, and expression of neurotrophic factors. We investigate the effects of CBL in the hAPP tg model of AD on levels of neurotrophic factors, including pro-nerve growth factor (NGF), NGF, brain-derived neurotrophic factor (BDNF), neurotropin (NT)-3, NT4, and ciliary neurotrophic factor (CNTF). Immunoblot analysis demonstrated that levels of pro-NGF were increased in saline-treated hAPP tg mice. In contrast, CBL-treated hAPP tg mice showed levels of pro-NGF comparable to control and increased levels of mature NGF. Consistently with these results, immunohistochemical analysis demonstrated increased NGF immunoreactivity in the hippocampus of CBL-treated hAPP tg mice. Protein levels of other neurotrophic factors, including BDNF, NT3, NT4, and CNTF, were unchanged. mRNA levels of NGF and other neurotrophins were also unchanged. Analysis of neurotrophin receptors showed preservation of the levels of TrKA and p75(NTR) immunoreactivity per cell in the nucleus basalis. Cholinergic cells in the nucleus basalis were reduced in the saline-treated hAPP tg mice, and treatment with CBL reduced these cholinergic deficits. These results suggest that the neurotrophic effects of CBL might involve modulation of the pro-NGF/NGF balance and a concomitant protection of cholinergic neurons. Copyright © 2012 Wiley Periodicals, Inc.

  10. Model-based Small Area Estimates of Cancer Risk Factors and Screening Behaviors - Small Area Estimates

    Science.gov (United States)

    These model-based estimates use two surveys, the Behavioral Risk Factor Surveillance System (BRFSS) and the National Health Interview Survey (NHIS). The two surveys are combined using novel statistical methodology.

  11. The Five-Factor Model of Personality and Borderline Personality Disorder: A Genetic Analysis of Comorbidity

    NARCIS (Netherlands)

    Distel, M.A.; Trull, T.J.; Willemsen, G.; Vink, J.M.; Derom, C.A.; Lynskey, M.; Martin, N.G.; Boomsma, D.I.

    2009-01-01

    Background: Recently, the nature of personality disorders and their relationship with normal personality traits has received extensive attention. The five-factor model (FFM) of personality, consisting of the personality traits neuroticism, extraversion, openness to experience, agreeableness, and

  12. The Butterfly Effect: Correlations Between Modeling in Nuclear-Particle Physics and Socioeconomic Factors

    CERN Document Server

    Pia, Maria Grazia; Bell, Zane W.; Dressendorfer, Paul V.

    2010-01-01

    A scientometric analysis has been performed on selected physics journals to estimate the presence of simulation and modeling in physics literature in the past fifty years. Correlations between the observed trends and several social and economical factors have been evaluated.

  13. A receptor model for urban aerosols based on oblique factor analysis

    DEFF Research Database (Denmark)

    Keiding, Kristian; Sørensen, Morten S.; Pind, Niels

    1987-01-01

    A procedure is outlined for the construction of receptor models of urban aerosols, based on factor analysis. The advantage of the procedure is that the covariation of source impacts is included in the construction of the models. The results are compared with results obtained by other receptor......-modelling procedures. It was found that procedures based on correlating sources were physically sound as well as in mutual agreement. Procedures based on non-correlating sources were found to generate physically obscure models....

  14. Extracting the Evaluations of Stereotypes: Bi-factor Model of the Stereotype Content Structure

    Directory of Open Access Journals (Sweden)

    Pablo Sayans-Jiménez

    2017-10-01

    Full Text Available Stereotype dimensions—competence, morality and sociability—are fundamental to studying the perception of other groups. These dimensions have shown moderate/high positive correlations with each other that do not reflect the theoretical expectations. The explanation for this (e.g., halo effect undervalues the utility of the shared variance identified. In contrast, in this work we propose that this common variance could represent the global evaluation of the perceived group. Bi-factor models are proposed to improve the internal structure and to take advantage of the information representing the shared variance among dimensions. Bi-factor models were compared with first order models and other alternative models in three large samples (300–309 participants. The relationships among the global and specific bi-factor dimensions with a global evaluation dimension (measured through a semantic differential were estimated. The results support the use of bi-factor models rather than first order models (and other alternative models. Bi-factor models also show a greater utility to directly and more easily explore the stereotype content including its evaluative content.

  15. Extracting the Evaluations of Stereotypes: Bi-factor Model of the Stereotype Content Structure.

    Science.gov (United States)

    Sayans-Jiménez, Pablo; Cuadrado, Isabel; Rojas, Antonio J; Barrada, Juan R

    2017-01-01

    Stereotype dimensions-competence, morality and sociability-are fundamental to studying the perception of other groups. These dimensions have shown moderate/high positive correlations with each other that do not reflect the theoretical expectations. The explanation for this (e.g., halo effect) undervalues the utility of the shared variance identified. In contrast, in this work we propose that this common variance could represent the global evaluation of the perceived group. Bi-factor models are proposed to improve the internal structure and to take advantage of the information representing the shared variance among dimensions. Bi-factor models were compared with first order models and other alternative models in three large samples (300-309 participants). The relationships among the global and specific bi-factor dimensions with a global evaluation dimension (measured through a semantic differential) were estimated. The results support the use of bi-factor models rather than first order models (and other alternative models). Bi-factor models also show a greater utility to directly and more easily explore the stereotype content including its evaluative content.

  16. Risk management under a two-factor model of the term structure of interest rates

    OpenAIRE

    Manuel Moreno

    1997-01-01

    This paper presents several applications to interest rate risk management based on a two-factor continuous-time model of the term structure of interest rates previously presented in Moreno (1996). This model assumes that default free discount bond prices are determined by the time to maturity and two factors, the long-term interest rate and the spread (difference between the long-term rate and the short-term (instantaneous) riskless rate). Several new measures of ``generalized duration" are p...

  17. Effect of Necessary Factors for Deploying E-Business Models on Business Performance in Automotive Industry

    OpenAIRE

    Mohsen Shafiei Nikabadi; Laya Olfat; Ahmad Jafarian; Hassan Alibabaei Khamene

    2013-01-01

    The main goal of this article is to survey effects of necessary factors for deploying e-business models on business performance in automotive industry. Today, application of information technology and internet in business is turned to a critical tool to gain competitive advantages in business. The impact of e-businesses is so that changed competitive approach between companies from traditional to modern models. In this study, first, necessary key factors of implementing e-business in automoti...

  18. Testing multi-factor asset pricing models in the Visegrad countries

    Czech Academy of Sciences Publication Activity Database

    Morgese Borys, Magdalena

    2011-01-01

    Roč. 61, č. 2 (2011), s. 118-139 ISSN 0015-1920 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:AV0Z70850503 Keywords : capital asset pricing model * macroeconomic factor models * asset pricing Subject RIV: AH - Economics Impact factor: 0.346, year: 2011 http://journal.fsv.cuni.cz/mag/article/show/id/1208

  19. Conditional Tests of Factor Augmented Asset Pricing Models with Human Capital and Housing: Some New Results

    OpenAIRE

    Olga Klinkowska

    2009-01-01

    In this paper I develop the asset pricing model in which the wealth portfolio is enriched with human capital and housing capital. These two types of capital account for a significant portion of the total wealth. Additionally I introduce dynamics into the model and represent conditioning information by common factors estimated with dynamic factor methodology. In this way I can use more accurate representative of the unobservable information set of the investors. Obtained results prove that ind...

  20. Rotation in the Dynamic Factor Modeling of Multivariate Stationary Time Series.

    Science.gov (United States)

    Molenaar, Peter C. M.; Nesselroade, John R.

    2001-01-01

    Proposes a special rotation procedure for the exploratory dynamic factor model for stationary multivariate time series. The rotation procedure applies separately to each univariate component series of a q-variate latent factor series and transforms such a component, initially represented as white noise, into a univariate moving-average.…