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Sample records for mucoid conversion biased

  1. Investigation of the algT operon sequence in mucoid and non-mucoid Pseudomonas aeruginosa isolates from 115 Scandinavian patients with cystic fibrosis and in 88 in vitro non-mucoid revertants

    DEFF Research Database (Denmark)

    Ciofu, Oana; Lee, Baoleri; Johannesson, Marie

    2008-01-01

    Pseudomonas aeruginosa is the dominant pathogen causing chronic lung infections in patients with cystic fibrosis (CF). After an initial phase characterized by intermittent colonizations, a chronic infection is established upon conversion of P. aeruginosa from the non-mucoid to the mucoid, alginate...

  2. Mucoid conversion of Pseudomonas aeruginosa by hydrogen peroxide: a mechanism for virulence activation in the cystic fibrosis lung

    DEFF Research Database (Denmark)

    Mathee, Kalai; Ciofu, Oana; Sternberg, Claus

    1999-01-01

    leukocytes (PMNs), which release free oxygen radicals such as H(2)O(2) The mucoid phenotype among the strains infecting CF patients indicates overproduction of a linear polysaccharide called alginate. To mimic the inflammatory environment of the CF lung, P. aeruginosa PAO1, a typical non-mucoid strain....... These findings indicate that gene activation in bacteria by toxic oxygen radicals, similar to that found in plants and mammalian cells, may serve as a defence mechanism for the bacteria. This suggests that mucoid conversion is a response to oxygen radical exposure and that this response is a mechanism of defence...... by the bacteria. This is the first report to show that PMNs and their oxygen radicals can cause this phenotypic and genotypic change which is so typical of the intractable form of P. aeruginosa in the CF lung. These findings may provide a basis for the development of anti-oxidant and anti-inflammatory therapy...

  3. Methods of detecting and controlling mucoid Pseudomonas biofilm production

    Science.gov (United States)

    Yu, Hongwei D. (Inventor); Qiu, Dongru (Inventor)

    2013-01-01

    Compositions and methods for detecting and controlling the conversion to mucoidy in Pseudomonas aeruginosa are disclosed. The present invention provides for detecting the switch from nonmucoid to mucoid state of P. aeruginosa by measuring mucE expression or MucE protein levels. The interaction between MucE and AlgW controls the switch to mucoidy in wild type P. aeruginosa. Also disclosed is an alginate biosynthesis heterologous expression system for use in screening candidate substances that inhibit conversion to mucoidy.

  4. Psl Produced by Mucoid Pseudomonas aeruginosa Contributes to the Establishment of Biofilms and Immune Evasion.

    Science.gov (United States)

    Jones, Christopher J; Wozniak, Daniel J

    2017-06-20

    Despite years of research and clinical advances, chronic pulmonary infections with mucoid Pseudomonas aeruginosa remain the primary concern for cystic fibrosis patients. Much of the research on these strains has focused on the contributions of the polysaccharide alginate; however, it is becoming evident that the neutral polysaccharide Psl also contributes to biofilm formation and the maintenance of chronic infections. Here, we demonstrate that Psl produced by mucoid strains has significant roles in biofilm structure and evasion of immune effectors. Though mucoid strains produce less Psl than nonmucoid strains, the Psl that is produced is functional, since it mediates adhesion to human airway cells and epithelial cell death. Additionally, Psl protects mucoid bacteria from opsonization and killing by complement components in human serum. Psl production by mucoid strains stimulates a proinflammatory response in the murine lung, leading to reduced colonization. To determine the relevance of these data to clinical infections, we tested Psl production and biofilm formation of a panel of mucoid clinical isolates. We demonstrated three classes of mucoid isolates, those that produce Psl and form robust biofilms, those that did not produce Psl and have a poor biofilm phenotype, and exopolysaccharide (EPS) redundant strains. Collectively, these experimental results demonstrate that Psl contributes to the biofilm formation and immune evasion of many mucoid strains. This is a novel role for Psl in the establishment and maintenance of chronic pulmonary infections by mucoid strains. IMPORTANCE Cystic fibrosis patients are engaged in an ongoing battle against chronic lung infections by the bacterium Pseudomonas aeruginosa One key factor contributing to the maintenance of chronic infections is the conversion to a mucoid phenotype, where the bacteria produce copious amounts of the polysaccharide alginate. Once the bacteria become mucoid, existing treatments are poorly effective. We

  5. Radiological study of bronchial mucoid impaction

    International Nuclear Information System (INIS)

    Yu Xiaoyi; Yan Hongzhen; Wang Tongde; Gan Chunlan; Liu Wei; Wang Linhui

    1999-01-01

    Objective: To evaluate the radiological findings of bronchial mucoid impaction in 28 patients in order to improve diagnostic efficacy. Methods: Standard posteroanterior high voltage radiographs were performed in all 28 cases. Among them CT scans were taken in 14 cases, while 3 patients underwent HRCT examination at the same time. Twenty-two patients had a history of expectoration of mucous plugs; in one case with pulmonary atelectasis, a mucous plug was picked out through bronchoscopy. The other 5 cases experienced a lung operation, and a tumor and bronchial mucoid impaction were discovered. Results: Radiographs showed most mucoid impaction as thick, branching structures resembling branches of tree; others were in the shapes of spherical, small clubs, and cuttle fish. In one patient, pulmonary atelectasis was the only radiographic finding. Similarly on CT, most bronchial mucoid impaction were likened to tree branches; the rest presented as small clubs and bunches of grape. A prominent feature of bronchial mucoid impaction, either on plain radiograph or on CT, was that its axis pointed to the hilum, completely consistent with the branching and distribution of the bronchi, and accompanied by bronchiectasis. Conclusions: It is an optimal approach to exploit plain radiograph combined with CT to find out bronchial mucoid impaction. An awareness of its clinical and radiological features may improve better understanding and recognition of the disease

  6. A case report of mucoid retention cyst in maxillary sinus

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Han Pyoung [College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    1973-11-15

    The author have observed mucoid retention cyst in the right maxillary sinus of the patient, 41 year old woman, complained discharging of purulent exudate on the right maxillary molar area, and obtained the following conclusions; 1. The mucoid retention cyst in maxillary sinus casts a faint dome shaped shadow into the radiolucent image of maxillary sinus. 2. The mucoid retention cyst in maxillary sinus may occurred without the history of trauma. 3. Intraoral standard films are also valuable for the interpretation of the lesions in maxillary sinus but only extraoral roentgenograms.

  7. A strong deletion bias in nonallelic gene conversion.

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    Raquel Assis

    Full Text Available Gene conversion is the unidirectional transfer of genetic information between orthologous (allelic or paralogous (nonallelic genomic segments. Though a number of studies have examined nucleotide replacements, little is known about length difference mutations produced by gene conversion. Here, we investigate insertions and deletions produced by nonallelic gene conversion in 338 Drosophila and 10,149 primate paralogs. Using a direct phylogenetic approach, we identify 179 insertions and 614 deletions in Drosophila paralogs, and 132 insertions and 455 deletions in primate paralogs. Thus, nonallelic gene conversion is strongly deletion-biased in both lineages, with almost 3.5 times as many conversion-induced deletions as insertions. In primates, the deletion bias is considerably stronger for long indels and, in both lineages, the per-site rate of gene conversion is orders of magnitudes higher than that of ordinary mutation. Due to this high rate, deletion-biased nonallelic gene conversion plays a key role in genome size evolution, leading to the cooperative shrinkage and eventual disappearance of selectively neutral paralogs.

  8. Polysaccharides serve as scaffold of biofilms formed by mucoid Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Yang, Liang; Hengzhuang, Wang; Wu, Hong

    2012-01-01

    Chronic lung infection by mucoid Pseudomonas aeruginosa is one of the major pathologic features in patients with cystic fibrosis. Mucoid P. aeruginosa is notorious for its biofilm forming capability and resistance to immune attacks. In this study, the roles of extracellular polymeric substances f...

  9. Pharmacokinetics/Pharmacodynamics of Colistin and Imipenem on Mucoid and Nonmucoid Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Hengzhuang, Wang; Wu, Hong; Ciofu, Oana

    2011-01-01

    The time course activity of Colistin and Imipenem on mucoid and non-mucoid biofilm-growing P. aeruginosa showed that compared with planktonic bacteria, the kinetics of Colistin and Imipenem retained the concentration- and time-dependent killings, respectively but higher doses of antibiotics and f...

  10. Mucoid impaction presenting as multiple pulmonary nodules in cystic fibrosis

    International Nuclear Information System (INIS)

    Carpenter, L.D.; Lambie, N.K.; Wilsher, M.L.

    1996-01-01

    Mucoid impaction has been described as a complication of asthma and more commonly in patients with allergic bronchopulmonary aspergillosis. In such cases, the impacted pools of mucus may present as discrete nodules on chest X-ray and hence simulate the appearance of metastatic malignancy. A case of mucoid impaction presenting as multiple pulmonary nodules in a patient with cystic fibrosis is described. The chest X-ray showed hyperinfiltration and scattered changes consistent with bronchiectasis. Computed tomography scan confirmed these and additional intra-pulmonary nodular densities. This report illustrates that mucus impaction as a cause of pulmonary nodules should be considered in any patient with chronic lung disease characterised by excess mucus production. 6 refs., 3 figs

  11. Mucoid Pseudomonas aeruginosa isolates maintain the biofilm formation capacity and the gene expression profiles during the chronic lung infection of CF patients

    DEFF Research Database (Denmark)

    Lee, Bao le ri; Schjerling, Charlotte K.; Kirkby, Nikolai

    2011-01-01

    Phenotypic and genotypic diversifications of Pseudomonas aeruginosa in the airways of patients with cystic fibrosis (CF) promote long-term survival of bacteria during chronic lung infection. Twelve clonally related, sequential mucoid and non-mucoid paired P. aeruginosa isolates obtained from three......-mucoid isolates observed in this particular P. aeruginosa clone reflects different adaptation strategies used by these two phenotypes in the different niches of the CF lung environment....

  12. Stress conditions triggering mucoid morphotype variation in Burkholderia species and effect on virulence in Galleria mellonella and biofilm formation in vitro.

    Directory of Open Access Journals (Sweden)

    Inês N Silva

    Full Text Available Burkholderia cepacia complex (Bcc bacteria are opportunistic pathogens causing chronic respiratory infections particularly among cystic fibrosis patients. During these chronic infections, mucoid-to-nonmucoid morphotype variation occurs, with the two morphotypes exhibiting different phenotypic properties. Here we show that in vitro, the mucoid clinical isolate Burkholderia multivorans D2095 gives rise to stable nonmucoid variants in response to prolonged stationary phase, presence of antibiotics, and osmotic and oxidative stresses. Furthermore, in vitro colony morphotype variation within other members of the Burkholderia genus occurred in Bcc and non-Bcc strains, irrespectively of their clinical or environmental origin. Survival to starvation and iron limitation was comparable for the mucoid parental isolate and the respective nonmucoid variant, while susceptibility to antibiotics and to oxidative stress was increased in the nonmucoid variants. Acute infection of Galleria mellonella larvae showed that, in general, the nonmucoid variants were less virulent than the respective parental mucoid isolate, suggesting a role for the exopolysaccharide in virulence. In addition, most of the tested nonmucoid variants produced more biofilm biomass than their respective mucoid parental isolate. As biofilms are often associated with increased persistence of pathogens in the CF lungs and are an indicative of different cell-to-cell interactions, it is possible that the nonmucoid variants are better adapted to persist in this host environment.

  13. Mucoid degeneration of the anterior cruciate ligament with erosion of the lateral femoral condyle

    International Nuclear Information System (INIS)

    Melloni, Pietro; Valls, Rafael; Yuguero, Mariano; Saez, Amparo

    2004-01-01

    We report a case of a mucoid degeneration of the anterior cruciate ligament (ACL) that produced osseous erosion of the medial aspect of the lateral femoral condyle. The MRI findings and differential diagnosis are discussed. (orig.)

  14. Chronic infection of cystic fibrosis patient airways by a single clone of Burkholderia cepacia: replacement of non-mucoid to mucoid morphotype Infecção pulmonar crônica por um único clone de Burkholderia cepacia: substituição do morfotipo não mucóide por mucóide

    Directory of Open Access Journals (Sweden)

    Ana Paula D'Alincourt Carvalho

    2003-11-01

    Full Text Available Mucoid Burkholderia cepacia morphotype emerged within a nine year follow-up of a cystic fibrosis patient. Clinical data suggested a linkage between the mucoid phenotype isolation and the deterioration of the patient's condition. Despite of the phenotypic variation, molecular typing showed that the patient was chronically infected with B. cepacia complex isolates belonging to a same genetic clone.O presente trabalho descreve a emergência de cepas mucoides do complexo B. cepacia em um paciente com Fibrose Cística dentro de um acompanhamento bacteriológico prospectivo de nove anos. Os dados clínicos sugerem a associação entre o isolamento do morfotipo mucoide e a deterioração clínica do paciente. Apesar da variação fenotípica, os testes moleculares mostraram que o paciente manteve-se cronicamente infectado por cepas de mesma origem clonal.

  15. Mucoid degeneration of the anterior cruciate ligament: Management and outcome

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    Vivek Pandey

    2014-01-01

    Full Text Available Background: Mucoid degeneration (MD is a rare pathological affection of the anterior cruciate ligament (ACL. Mucinous material within the substance of ACL produces pain and limited motion in the knee. This series describes the clinicoradiological presentation of patients with mucoid ACL, partial arthroscopic debridement of ACL and outcomes. Materials and Methods: During a period of 3 years, 11 patients were included based upon the clinical suspicion, magnetic resonance imaging (MRI findings, arthroscopic features and histopathologic confirmation of MD of ACL. Result: Six patients were male and five were female with median age of 40 years (range 21-59 years. All patients complained of knee pain with median duration of 5 months (range 1-24 months. All patients had painful deep flexion with 63.6% (N = 7 reporting trivial trauma before the onset of symptoms. MRI revealed MD of ACL in all with associated cyst in three patients. Partial debridement of ACL was done in ten and complete in one patient. None of them required notchplasty. Histopathology confirmed the diagnosis in all of them. At the mean followup of 13.81 months (range 6-28 months, all patients regained complete flexion and none complained of instability. Conclusion: Prior knowledge of condition with high index of suspicion and careful interpretation of MRI can establish the diagnosis preoperatively. It responds well to partial debridement of ACL and mucinous material without development of instability.

  16. Mutational Biases and GC-Biased Gene Conversion Affect GC Content in the Plastomes of Dendrobium Genus

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    Zhitao Niu

    2017-11-01

    Full Text Available The variation of GC content is a key genome feature because it is associated with fundamental elements of genome organization. However, the reason for this variation is still an open question. Different kinds of hypotheses have been proposed to explain the variation of GC content during genome evolution. However, these hypotheses have not been explicitly investigated in whole plastome sequences. Dendrobium is one of the largest genera in the orchid species. Evolutionary studies of the plastomic organization and base composition are limited in this genus. In this study, we obtained the high-quality plastome sequences of D. loddigesii and D. devonianum. The comparison results showed a nearly identical organization in Dendrobium plastomes, indicating that the plastomic organization is highly conserved in Dendrobium genus. Furthermore, the impact of three evolutionary forces—selection, mutational biases, and GC-biased gene conversion (gBGC—on the variation of GC content in Dendrobium plastomes was evaluated. Our results revealed: (1 consistent GC content evolution trends and mutational biases in single-copy (SC and inverted repeats (IRs regions; and (2 that gBGC has influenced the plastome-wide GC content evolution. These results suggest that both mutational biases and gBGC affect GC content in the plastomes of Dendrobium genus.

  17. Mutational Biases and GC-Biased Gene Conversion Affect GC Content in the Plastomes of Dendrobium Genus

    Science.gov (United States)

    Niu, Zhitao; Xue, Qingyun; Wang, Hui; Xie, Xuezhu; Zhu, Shuying; Liu, Wei; Ding, Xiaoyu

    2017-01-01

    The variation of GC content is a key genome feature because it is associated with fundamental elements of genome organization. However, the reason for this variation is still an open question. Different kinds of hypotheses have been proposed to explain the variation of GC content during genome evolution. However, these hypotheses have not been explicitly investigated in whole plastome sequences. Dendrobium is one of the largest genera in the orchid species. Evolutionary studies of the plastomic organization and base composition are limited in this genus. In this study, we obtained the high-quality plastome sequences of D. loddigesii and D. devonianum. The comparison results showed a nearly identical organization in Dendrobium plastomes, indicating that the plastomic organization is highly conserved in Dendrobium genus. Furthermore, the impact of three evolutionary forces—selection, mutational biases, and GC-biased gene conversion (gBGC)—on the variation of GC content in Dendrobium plastomes was evaluated. Our results revealed: (1) consistent GC content evolution trends and mutational biases in single-copy (SC) and inverted repeats (IRs) regions; and (2) that gBGC has influenced the plastome-wide GC content evolution. These results suggest that both mutational biases and gBGC affect GC content in the plastomes of Dendrobium genus. PMID:29099062

  18. Trichosporon inkin and Trichosporon mucoides as unusual causes of white piedra of scalp hair.

    Science.gov (United States)

    Tendolkar, Uma; Shinde, Alka; Baveja, Sujata; Dhurat, Rachita; Phiske, Meghana

    2014-01-01

    White piedra of scalp hair is considered a rare entity. We report three cases of this disorder all of whom presented with nodules on the hair. Potassium hydroxide preparations of the hair revealed clustered arthrospores and mature, easily detachable nodules. Cultures grew Trichosporon inkin in 2 patients and Trichosporon mucoides in one patient. Both these fungi are unusual causes of white piedra.

  19. Microbial pathogenesis in cystic fibrosis: co-ordinate regulation of heat-shock response and conversion to mucoidy in Pseudomonas aeruginosa.

    Science.gov (United States)

    Schurr, M J; Deretic, V

    1997-04-01

    Conversion of Pseudomonas aeruginosa to the mucoid phenotype plays a major role in the pathogenesis of respiratory infections in cystic fibrosis (CF). One mechanism responsible for mucoidy is based on mutations that inactivate the anti-sigma factor, MucA, which normally inhibits the alternative sigma factor, AIgU. The loss of MucA allows AIgU to freely direct transcription of the genes responsible for the production of the exopolysaccharide alginate resulting in mucoid colony morphology. In Escherichia coli, a close homologue of AIgU, sigma(E), directs transcription of several genes under conditions of extreme heat shock. Here we examined whether AIgU, besides its role in controlling alginate production, affects the heat-shock response in P. aeruginosa. The P. aeruginosa rpoH gene encoding a homologue of the major heat-shock sigma factor, sigma32, was found to be transcribed by AIgU containing RNA polymerase from one of its promoters (P3) identified in this study. Transcription of rpoH from P3 was elevated upon exposure to extreme heat shock in an aIgU-dependent manner. Importantly, the AIgU-dependent promoter of rpoH was found to be activated in mucoid mucA mutants. In keeping with this observation, introduction of a wild-type mucA gene abrogated AIgU-dependent rpoH transcription in mucoid P. aeruginosa laboratory isolates and CF isolates. These results suggest that conversion to mucoidy and the heat-shock response are co-ordinately regulated in P. aeruginosa. The simultaneous activation of both systems in mucA mutants, selected in the lungs of CF patients, may have significance for the inflammatory processes characteristic of the establishment of chronic infection and ensuing clinical deterioration in CF.

  20. Trichosporon inkin and Trichosporon mucoides as unusual causes of white piedra of scalp hair

    Directory of Open Access Journals (Sweden)

    Uma Tendolkar

    2014-01-01

    Full Text Available White piedra of scalp hair is considered a rare entity. We report three cases of this disorder all of whom presented with nodules on the hair. Potassium hydroxide preparations of the hair revealed clustered arthrospores and mature, easily detachable nodules. Cultures grew Trichosporon inkin in 2 patients and Trichosporon mucoides in one patient. Both these fungi are unusual causes of white piedra.

  1. Genome Sequence of Pseudomonas aeruginosa Strain DK1-NH57388A, a Stable Mucoid Cystic Fibrosis Isolate

    DEFF Research Database (Denmark)

    Norman, Anders; Ciofu, Oana; Amador Hierro, Cristina Isabel

    2016-01-01

    Pseudomonas aeruginosa is an important opportunistic pathogen associated with chronic pulmonary infections and mortality in cystic fibrosis (CF) patients. Here, we present the complete genome sequence of stable mucoid P. aeruginosa strain DK1-NH57388A, a CF isolate which has previously been used...

  2. Opposing Forces of A/T-Biased Mutations and G/C-Biased Gene Conversions Shape the Genome of the Nematode Pristionchus pacificus

    Science.gov (United States)

    Weller, Andreas M.; Rödelsperger, Christian; Eberhardt, Gabi; Molnar, Ruxandra I.; Sommer, Ralf J.

    2014-01-01

    Base substitution mutations are a major source of genetic novelty and mutation accumulation line (MAL) studies revealed a nearly universal AT bias in de novo mutation spectra. While a comparison of de novo mutation spectra with the actual nucleotide composition in the genome suggests the existence of general counterbalancing mechanisms, little is known about the evolutionary and historical details of these opposing forces. Here, we correlate MAL-derived mutation spectra with patterns observed from population resequencing. Variation observed in natural populations has already been subject to evolutionary forces. Distinction between rare and common alleles, the latter of which are close to fixation and of presumably older age, can provide insight into mutational processes and their influence on genome evolution. We provide a genome-wide analysis of de novo mutations in 22 MALs of the nematode Pristionchus pacificus and compare the spectra with natural variants observed in resequencing of 104 natural isolates. MALs show an AT bias of 5.3, one of the highest values observed to date. In contrast, the AT bias in natural variants is much lower. Specifically, rare derived alleles show an AT bias of 2.4, whereas common derived alleles close to fixation show no AT bias at all. These results indicate the existence of a strong opposing force and they suggest that the GC content of the P. pacificus genome is in equilibrium. We discuss GC-biased gene conversion as a potential mechanism acting against AT-biased mutations. This study provides insight into genome evolution by combining MAL studies with natural variation. PMID:24414549

  3. Bias magnetic field and test period dependences of direct and converse magnetoelectric hysteresis of tri-layered magnetoelectric composite

    Science.gov (United States)

    Zhou, Yun; Li, Xiao-Hong; Wang, Jian-Feng; Zhou, Hao-Miao; Cao, Dan; Jiao, Zhi-Wei; Xu, Long; Li, Qi-Hao

    2018-04-01

    The direct and converse magnetoelectric hysteresis behavior for a tri-layered composite has been comparatively investigated and significant similarities have been observed. The results show that both the direct and converse magnetoelectric hysteresis is deeply affected by the bias magnetic field and test period. The test time hysteresis caused by a fast varying bias magnetic field can be reduced by prolonging the test period. The observed coercive field, remanence, and ratio of remanence of the direct and converse magnetoelectric effects with the test period obey an exponential decay law. A hysteretic nonlinear magnetoelectric theoretical model for the symmetrical tri-layered structure has been proposed based on a nonlinear constitutive model and pinning effect. The numerical calculation shows that the theoretical results are in good agreement with the experimental results. These findings not only provide insight into the examination and practical applications of magnetoelectric materials, but also propose a theoretical frame for studying the hysteretic characteristics of the magnetoelectric effect.

  4. Genome Sequence of Pseudomonas aeruginosa Strain DK1-NH57388A, a Stable Mucoid Cystic Fibrosis Isolate

    DEFF Research Database (Denmark)

    Norman, Anders; Ciofu, Oana; Amador Hierro, Cristina Isabel

    2016-01-01

    Pseudomonas aeruginosa is an important opportunistic pathogen associated with chronic pulmonary infections and mortality in cystic fibrosis (CF) patients. Here, we present the complete genome sequence of stable mucoid P. aeruginosa strain DK1-NH57388A, a CF isolate which has previously been used ...

  5. Augmented effect of early antibiotic treatment in mice with experimental lung infections due to sequentially adapted mucoid strains of Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    van Gennip, M; Moser, Claus; Christensen, Louise D

    2009-01-01

    : A significant reduction in the number of bacteria was observed when initiating treatment 1 h post-infection compared with initiating treatment after 24 h, although the latest isolate avoided complete clearance. Early antibiotic treatment directed at the mucoid phenotype in mice also reduced the inflammation and......Background: Effects of treatment with tobramycin initiated 1 or 24 h post-infection were investigated in a new version of a pulmonary infection model in mice. The model reflects the differentiated behaviour of Pseudomonas aeruginosa mucoid strains isolated from the lungs of one chronically infected......, histopathology, and measurement of granulocyte colony-stimulating factor (G-CSF) and macrophage inflammatory protein 2 (MIP-2). Results: There was a significant reduction of bacteria when comparing treatment initiated 1 h post-infection with treatment initiated after 24 h for isolates 1997 and 2003. Treatment...

  6. 1000 human genomes carry widespread signatures of GC biased gene conversion.

    Science.gov (United States)

    Dutta, Rajib; Saha-Mandal, Arnab; Cheng, Xi; Qiu, Shuhao; Serpen, Jasmine; Fedorova, Larisa; Fedorov, Alexei

    2018-04-16

    GC-Biased Gene Conversion (gBGC) is one of the important theories put forward to explain profound long-range non-randomness in nucleotide compositions along mammalian chromosomes. Nucleotide changes due to gBGC are hard to distinguish from regular mutations. Here, we present an algorithm for analysis of millions of known SNPs that detects a subset of so-called "SNP flip-over" events representing recent gBGC nucleotide changes, which occurred in previous generations via non-crossover meiotic recombination. This algorithm has been applied in a large-scale analysis of 1092 sequenced human genomes. Altogether, 56,328 regions on all autosomes have been examined, which revealed 223,955 putative gBGC cases leading to SNP flip-overs. We detected a strong bias (11.7% ± 0.2% excess) in AT- > GC over GC- > AT base pair changes within the entire set of putative gBGC cases. On average, a human gamete acquires 7 SNP flip-over events, in which one allele is replaced by its complementary allele during the process of meiotic non-crossover recombination. In each meiosis event, on average, gBGC results in replacement of 7 AT base pairs by GC base pairs, while only 6 GC pairs are replaced by AT pairs. Therefore, every human gamete is enriched by one GC pair. Happening over millions of years of evolution, this bias may be a noticeable force in changing the nucleotide composition landscape along chromosomes.

  7. Submucosal lipoma of the sigmoid colon as a rare cause of mucoid diarrhea: a case report

    OpenAIRE

    Dassanayake, S. U. B.; Dinamithra, N. P.; Nawarathne, N. M. M.

    2016-01-01

    Background Symptomatic presentations of colonic lipomas are very rare in clinical practice, and may mimic colonic malignancy. The likelihood of presenting symptoms has been shown to depend on the size of the lesion. Case presentation We describe the case of a 72-year-old Sinhalese man presenting with worsening mucoid diarrhea who was subsequently diagnosed to have a lipoma of the sigmoid colon. His disease was successfully managed with endoscopic resection. Conclusion Confidently establishing...

  8. Social performance deficits in social anxiety disorder: reality during conversation and biased perception during speech.

    Science.gov (United States)

    Voncken, Marisol J; Bögels, Susan M

    2008-12-01

    Cognitive models emphasize that patients with social anxiety disorder (SAD) are mainly characterized by biased perception of their social performance. In addition, there is a growing body of evidence showing that SAD patients suffer from actual deficits in social interaction. To unravel what characterizes SAD patients the most, underestimation of social performance (defined as the discrepancy between self-perceived and observer-perceived social performance), or actual (observer-perceived) social performance, 48 patients with SAD and 27 normal control participants were observed during a speech and conversation. Consistent with the cognitive model of SAD, patients with SAD underestimated their social performance relative to control participants during the two interactions, but primarily during the speech. Actual social performance deficits were clearly apparent in the conversation but not in the speech. In conclusion, interactions that pull for more interpersonal skills, like a conversation, elicit more actual social performance deficits whereas, situations with a performance character, like a speech, bring about more cognitive distortions in patients with SAD.

  9. Submucosal lipoma of the sigmoid colon as a rare cause of mucoid diarrhea: a case report.

    Science.gov (United States)

    Dassanayake, S U B; Dinamithra, N P; Nawarathne, N M M

    2016-01-20

    Symptomatic presentations of colonic lipomas are very rare in clinical practice, and may mimic colonic malignancy. The likelihood of presenting symptoms has been shown to depend on the size of the lesion. We describe the case of a 72-year-old Sinhalese man presenting with worsening mucoid diarrhea who was subsequently diagnosed to have a lipoma of the sigmoid colon. His disease was successfully managed with endoscopic resection. Confidently establishing the rare diagnosis of a colonic lipoma usually requires a combination of endoscopic, radiological, and histological evaluation, and is therefore very challenging. With the advancement of endoscopic procedures, endoscopic resection is widely practiced as the definitive management of these cases.

  10. A complex multilevel attack on Pseudomonas aeruginosa algT/U expression and AlgT/U activity results in the loss of alginate production

    DEFF Research Database (Denmark)

    Sautter, Robert; Ramos, Damaris; Schneper, Lisa

    2012-01-01

    Infection by the opportunistic pathogen Pseudomonas aeruginosa is a leading cause of morbidity and mortality seen in cystic fibrosis (CF) patients. This is mainly due to the genotypic and phenotypic changes of the bacteria that cause conversion from a typical nonmucoid to a mucoid form in the CF...... lung. Mucoid conversion is indicative of overproduction of a capsule-like polysaccharide called alginate. The alginate-overproducing (Alg+) mucoid phenotype seen in the CF isolates is extremely unstable. Low oxygen tension growth of mucoid variants readily selects for nonmucoid variants. The switching...... complementation and sequencing of one Group B sap mutant, sap22, revealed that the nonmucoid phenotype was due to the presence of a mutation in PA3257. PA3257 encodes a putative periplasmic protease. Mutation of PA3257 resulted in decreased algT/U expression. Thus, inhibition of algT/U is a primary mechanism...

  11. The Impact of Selection, Gene Conversion, and Biased Sampling on the Assessment of Microbial Demography.

    Science.gov (United States)

    Lapierre, Marguerite; Blin, Camille; Lambert, Amaury; Achaz, Guillaume; Rocha, Eduardo P C

    2016-07-01

    Recent studies have linked demographic changes and epidemiological patterns in bacterial populations using coalescent-based approaches. We identified 26 studies using skyline plots and found that 21 inferred overall population expansion. This surprising result led us to analyze the impact of natural selection, recombination (gene conversion), and sampling biases on demographic inference using skyline plots and site frequency spectra (SFS). Forward simulations based on biologically relevant parameters from Escherichia coli populations showed that theoretical arguments on the detrimental impact of recombination and especially natural selection on the reconstructed genealogies cannot be ignored in practice. In fact, both processes systematically lead to spurious interpretations of population expansion in skyline plots (and in SFS for selection). Weak purifying selection, and especially positive selection, had important effects on skyline plots, showing patterns akin to those of population expansions. State-of-the-art techniques to remove recombination further amplified these biases. We simulated three common sampling biases in microbiological research: uniform, clustered, and mixed sampling. Alone, or together with recombination and selection, they further mislead demographic inferences producing almost any possible skyline shape or SFS. Interestingly, sampling sub-populations also affected skyline plots and SFS, because the coalescent rates of populations and their sub-populations had different distributions. This study suggests that extreme caution is needed to infer demographic changes solely based on reconstructed genealogies. We suggest that the development of novel sampling strategies and the joint analyzes of diverse population genetic methods are strictly necessary to estimate demographic changes in populations where selection, recombination, and biased sampling are present. © The Author 2016. Published by Oxford University Press on behalf of the Society for

  12. Biased Gene Conversion and GC-Content Evolution in the Coding Sequences of Reptiles and Vertebrates

    Science.gov (United States)

    Figuet, Emeric; Ballenghien, Marion; Romiguier, Jonathan; Galtier, Nicolas

    2015-01-01

    Mammalian and avian genomes are characterized by a substantial spatial heterogeneity of GC-content, which is often interpreted as reflecting the effect of local GC-biased gene conversion (gBGC), a meiotic repair bias that favors G and C over A and T alleles in high-recombining genomic regions. Surprisingly, the first fully sequenced nonavian sauropsid (i.e., reptile), the green anole Anolis carolinensis, revealed a highly homogeneous genomic GC-content landscape, suggesting the possibility that gBGC might not be at work in this lineage. Here, we analyze GC-content evolution at third-codon positions (GC3) in 44 vertebrates species, including eight newly sequenced transcriptomes, with a specific focus on nonavian sauropsids. We report that reptiles, including the green anole, have a genome-wide distribution of GC3 similar to that of mammals and birds, and we infer a strong GC3-heterogeneity to be already present in the tetrapod ancestor. We further show that the dynamic of coding sequence GC-content is largely governed by karyotypic features in vertebrates, notably in the green anole, in agreement with the gBGC hypothesis. The discrepancy between third-codon positions and noncoding DNA regarding GC-content dynamics in the green anole could not be explained by the activity of transposable elements or selection on codon usage. This analysis highlights the unique value of third-codon positions as an insertion/deletion-free marker of nucleotide substitution biases that ultimately affect the evolution of proteins. PMID:25527834

  13. Downwards Vertical Attention Bias in Conversion Disorder vs Controls: A Pilot Study.

    Science.gov (United States)

    Gazit, Sivan; Elkana, Odelia; Dawidowicz, Liraz; Yeshayahu, Liel; Biran, Iftah

    Conversion disorder (CD) is a largely enigmatic disorder, one that requires a thorough ruling-out process. Prior research suggests that metaphors and conceptualization are rooted in physical experience, and that we interpret our affective world through metaphors. Spatial metaphors (interaction of affect and vertical space) are a prominent example of the grounding of metaphors. This is a relatively unpaved direction of research of CD. The present pilot study sought to explore this view by investigating the "healthy is up, sick is down" spatial metaphors (e.g., "fell ill" and "top shape") in patients with CD, examining the correlation between the processing of bodily-related words, CD, and vertical space. We hypothesized that patients with CD, who experience their bodies as ill, will demonstrate a downwards bias when processing bodily-related words; corresponding to the "healthy is up, sick is down" spatial metaphor. A total of 8 female patients (ages M-38.13 SD-10.44) and 42 female controls (ages M-36.4 SD-14.57) performed a visual attention task. Participants were asked to identify a spatial probe at the top or the bottom of a screen, following either a bodily related (e.g., arm) or non-bodily related (e.g., clock) prime word. As predicted, when processing bodily-related words, patients with CD demonstrated a downwards attention bias. Moreover, the higher the patient's level of somatization, the faster the patient detected lower (vs upper) spatial targets. This study suggests that the changed health paradigm of patients with CD is grounded in sensorimotor perception. Further research could propose new diagnostic and treatment options for CD. Copyright © 2017 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.

  14. Dialogue Games for Inconsistent and Biased Information

    NARCIS (Netherlands)

    Lebbink, H.J.; Witteman, C.L.M.; Meyer, J.J.C.

    2003-01-01

    In this article, a dialogue game is presented in which coherent conversational sequences with inconsistent and biased information are described at the speech act level. Inconsistent and biased information is represented with bilattice structures, and based on these bilattice structures, a

  15. Relationship between mucoid hypertrophy of the anterior cruciate ligament (ACL) and morphologic change of the intercondylar notch: MRI and arthroscopy correlation

    International Nuclear Information System (INIS)

    Cha, Ji Hyeon; Shin, Myung Jin; Choi, Byeong Kyoo; Lee, Sang Hoon; Bin, Sung Il

    2008-01-01

    The purpose of this study was to evaluate the relationship between mucoid hypertrophy of the anterior cruciate ligament (ACL) and morphologic change of the intercondylar notch. We retrospectively reviewed the 105 patients with knee magnetic resonance imaging (MRI) with or without knee arthroscopy [group 1: patients with arthroscopic notchplasty (N = 47), group 2: knee arthroscopy demonstrating intact ACL (N = 33), and group 3: patients with normal knee MRI but no arthroscopy (N = 25)]. Groups 2 and 3 served as an arthroscopic and MR control group, respectively. Two musculoskeletal radiologists reviewed all MR examinations. The intercondylar notch width, notch index (width of intercondylar notch/width of femoral condyle), transverse notch angle (TNA), sagittal notch angle (SNA), and notch area were recorded on axial and sagittal MR images at the midpoint of Blumensaat's line which was identified on sagittal images. The diameter of the ACL was recorded on coronal MR images at the posterior end of Blumensaat's line. The mean values of the intercondylar notch width, notch index, TNA, SNA, notch area, and ACL diameter for the three groups were 16.0 mm/0.2/50.3 /36.5 /249.0 mm 2 /7.7 mm (group 1); 19.3 mm/0.3/52.9 /40.2 /323.4 mm 2 /4.8 mm (group 2); and 20.3 mm/0.3/51.4 /39.1 /350.8 mm 2 /4.5 mm (group 3). The intercondylar notch width, notch index, SNA, and notch area were smaller, and ACL diameter was thicker in group 1 compared with the other groups (p < 0.05). Patients with mucoid ACL hypertrophy show a narrower notch, a steeper notch angle, and a smaller notch area than control groups. (orig.)

  16. A fully integrated, wide-load-range, high-power-conversion-efficiency switched capacitor DC-DC converter with adaptive bias comparator for ultra-low-power power management integrated circuit

    Science.gov (United States)

    Asano, Hiroki; Hirose, Tetsuya; Kojima, Yuta; Kuroki, Nobutaka; Numa, Masahiro

    2018-04-01

    In this paper, we present a wide-load-range switched-capacitor DC-DC buck converter with an adaptive bias comparator for ultra-low-power power management integrated circuit. The proposed converter is based on a conventional one and modified to operate in a wide load range by developing a load current monitor used in an adaptive bias comparator. Measurement results demonstrated that our proposed converter generates a 1.0 V output voltage from a 3.0 V input voltage at a load of up to 100 µA, which is 20 times higher than that of the conventional one. The power conversion efficiency was higher than 60% in the load range from 0.8 to 100 µA.

  17. X-ray-to-current signal conversion characteristics of trench-structured photodiodes for direct-conversion-type silicon X-ray sensor

    International Nuclear Information System (INIS)

    Ariyoshi, Tetsuya; Funaki, Shota; Sakamoto, Kenji; Baba, Akiyoshi; Arima, Yutaka

    2017-01-01

    To reduce the radiation dose required in medical X-ray diagnoses, we propose a high-sensitivity direct-conversion-type silicon X-ray sensor that uses trench-structured photodiodes. This sensor is advantageous in terms of its long device lifetime, noise immunity, and low power consumption because of its low bias voltage. With this sensor, it is possible to detect X-rays with almost 100% efficiency; sensitivity can therefore be improved by approximately 10 times when compared with conventional indirect-conversion-type sensors. In this study, a test chip was fabricated using a single-poly single-metal 0.35 μm process. The formed trench photodiodes for the X-ray sensor were approximately 170 and 300 μm deep. At a bias voltage of 25 V, the absorbed X-ray-to-current signal conversion efficiencies were 89.3% (theoretical limit; 96.7%) at a trench depth of 170 μm and 91.1% (theoretical limit; 94.3%) at a trench depth of 300 μm. (author)

  18. Approach bias for food cues in obese individuals.

    Science.gov (United States)

    Kemps, Eva; Tiggemann, Marika

    2015-01-01

    This study aimed to investigate the existence of an approach bias for food cues in obese individuals. A community sample of 56 obese women and 56 normal weight controls completed an approach-avoidance variant of the implicit association task. The obese participants were faster to respond to trials that paired food words with approach words, and trials that paired non-food words with avoid words, than the converse pairings, thus, demonstrating an approach bias for food. This bias was evident for both high caloric and low caloric food words, and was not attributable to a state of deprivation or feelings of hunger. By contrast, the normal weight controls did not show any such bias. The results are consistent with recent neurocognitive perspectives of obesity. At a practical level, approach biases for food may present a potential target for modifying (excessive) food intake.

  19. A survey of prosthetic eye wearers to investigate mucoid discharge

    Directory of Open Access Journals (Sweden)

    Pine K

    2012-05-01

    Full Text Available Keith Pine1, Brian Sloan2, Joanna Stewart3, Robert J Jacobs11Department of Optometry and Vision Science, 2Department of Ophthalmology, New Zealand National Eye Centre, 3Section of Epidemiology and Biostatistics, School of Population Health, University of Auckland, Auckland, New ZealandBackground: This study aimed to better understand the causes and treatments of mucoid discharge associated with prosthetic eye wear by reviewing the literature and surveying anophthalmic patients.Methods: An anonymous questionnaire was completed by 429 prosthetic eye wearers who used visual analog scales to self-measure their discharge experience for four discharge characteristics: frequency, color, volume, and viscosity. These characteristics were analyzed with age, ethnicity, years wearing a prosthesis, eye loss cause, removal and cleaning regimes, hand-washing behavior, age of current prosthesis, and professional repolishing regimes as explanatory variables. Eighteen ocularists’ Web sites containing comments on the cause and treatment of discharge were surveyed.Results: Associations were found between discharge frequency and cleaning regimes with more frequent cleaning accompanying more frequent discharge. Color was associated with years of wearing and age, with more years of wearing and older people having less colored discharge. Volume was associated with cleaning regimes with more frequent cleaners having more volume. Viscosity was associated with cleaning regimes and years of wearing with more frequent cleaning and shorter wearing time accompanying more viscous discharge. No associations were found between discharge characteristics and ethnicity, eye loss cause, hand washing, age of current prosthesis, or repolishing regimes. Forty-seven percent of ocularists’ Web sites advised that discharge was caused by surface deposits on the prosthesis, 29% by excessive handling of the prosthesis, and 24% by other causes.Conclusions: A standardized treatment

  20. Auditory hindsight bias: Fluency misattribution versus memory reconstruction.

    Science.gov (United States)

    Higham, Philip A; Neil, Greg J; Bernstein, Daniel M

    2017-06-01

    We report 4 experiments investigating auditory hindsight bias-the tendency to overestimate the intelligibility of distorted auditory stimuli after learning their identity. An associative priming manipulation was used to vary the amount of processing fluency independently of prior target knowledge. For hypothetical designs, in which hindsight judgments are made for peers in foresight, we predicted that judgments would be based on processing fluency and that hindsight bias would be greater in the unrelated- compared to related-prime context (differential-fluency hypothesis). Conversely, for memory designs, in which foresight judgments are remembered in hindsight, we predicted that judgments would be based on memory reconstruction and that there would be independent effects of prime relatedness and prior target knowledge (recollection hypothesis). These predictions were confirmed. Specifically, we found support for the differential-fluency hypothesis when a hypothetical design was used in Experiments 1 and 2 (hypothetical group). Conversely, when a memory design was used in Experiments 2 (memory group), 3A, and 3B, we found support for the recollection hypothesis. Together, the results suggest that qualitatively different mechanisms create hindsight bias in the 2 designs. The results are discussed in terms of fluency misattributions, memory reconstruction, anchoring-and-adjustment, sense making, and a multicomponent model of hindsight bias. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  1. Pseudomonas aeruginosa alginate is refractory to Th1 immune response and impedes host immune clearance in a mouse model of acute lung infection

    DEFF Research Database (Denmark)

    Song, Zhijun; Wu, Hong; Ciofu, Oana

    2003-01-01

    . The effect of alginate production on pathogenicity was investigated by using an acute lung infection mouse model that compared a non-mucoid P. aeruginosa strain, PAO1, to its constitutive alginate-overproducing derivative, Alg(+) PAOmucA22, and an alginate-defective strain, Alg(-) PAOalgD. Bacterial......Pseudomonas aeruginosa is an opportunistic respiratory pathogen that accounts for most of the morbidity and mortality in cystic fibrosis (CF) patients. In CF-affected lungs, the bacteria undergo conversion from a non-mucoid to a non-tractable mucoid phenotype, due to overproduction of alginate...... suspensions were instilled into the left bronchus and examined 24 and 48 h post-infection. The highest bacterial loads and the most severe lung pathology were observed with strain Alg(-) PAOalgD at 24 h post-infection, which may have been due to an increase in expression of bacterial elastase by the mutant...

  2. Analysis of 62 hybrid assembled human Y chromosomes exposes rapid structural changes and high rates of gene conversion

    DEFF Research Database (Denmark)

    Gonzalez-Izarzugaza, Jose Maria; Skov, Laurits; Maretty, Lasse

    2017-01-01

    with the chimpanzee Y chromosome. We analyzed 2.7 Mb of large inverted repeats (palindromes) for variation patterns among the two palindrome arms and identified 603 mutation and 416 gene conversions events. We find clear evidence for GC-biased gene conversion in the palindromes (and a balancing AT mutation bias...

  3. High and far: biases in the location of protected areas.

    Directory of Open Access Journals (Sweden)

    Lucas N Joppa

    Full Text Available BACKGROUND: About an eighth of the earth's land surface is in protected areas (hereafter "PAs", most created during the 20(th century. Natural landscapes are critical for species persistence and PAs can play a major role in conservation and in climate policy. Such contributions may be harder than expected to implement if new PAs are constrained to the same kinds of locations that PAs currently occupy. METHODOLOGY/PRINCIPAL FINDINGS: Quantitatively extending the perception that PAs occupy "rock and ice", we show that across 147 nations PA networks are biased towards places that are unlikely to face land conversion pressures even in the absence of protection. We test each country's PA network for bias in elevation, slope, distances to roads and cities, and suitability for agriculture. Further, within each country's set of PAs, we also ask if the level of protection is biased in these ways. We find that the significant majority of national PA networks are biased to higher elevations, steeper slopes and greater distances to roads and cities. Also, within a country, PAs with higher protection status are more biased than are the PAs with lower protection statuses. CONCLUSIONS/SIGNIFICANCE: In sum, PAs are biased towards where they can least prevent land conversion (even if they offer perfect protection. These globally comprehensive results extend findings from nation-level analyses. They imply that siting rules such as the Convention on Biological Diversity's 2010 Target [to protect 10% of all ecoregions] might raise PA impacts if applied at the country level. In light of the potential for global carbon-based payments for avoided deforestation or REDD, these results suggest that attention to threat could improve outcomes from the creation and management of PAs.

  4. Transport of mucoid mucus in healthy individuals and patients with chronic obstructive pulmonary disease and bronchiectasis

    Directory of Open Access Journals (Sweden)

    J. Lima Afonso

    2013-09-01

    Full Text Available Objective: To characterize and compare the in vitro transport properties of respiratory mucoid secretion in individuals with no lung disease and in stable patients with chronic obstructive pulmonary disease (COPD and bronchiectasis. Methodology: Samples of mucus were collected from 21 volunteers presenting no lung disease who had undergone surgery, from 10 patients presenting chronic COPD, and from 16 patients with bronchiectasis. Mucociliary transport (MCT, transport by cough (SCM, and contact angle (CAM were evaluated. Results: MCT was found to be greater in healthy individuals (1.0 ± 0.19 than in COPD (0.91 ± 0.17 and bronchiectasis (0.76 ± 0.23 patients (p < 0.05, whereas SCM was greater in COPD patients (16.31 ± 7.35 cm than in patients with bronchiectasis (12.16 ± 6.64 cm and healthy individuals (10.50 ± 25.8 cm (p < 0.05. No significant differences were observed between the groups regarding CAM. Conclusion: Mucus from healthy individuals allows better mucociliary transport compared to that from patients with lung diseases. However, the mucus from COPD patients allows a better transport by coughing, demonstrating that these individuals have adapted to a defence mechanism compared to patients with bronchiectasis, who have impairment in their ciliary and cough transport mechanisms. Resumo: Objetivo: Analisar e comparar as propriedades de transporte in vitro da secreção respiratória de aspeto mucoide (M de indivíduos sem doença respiratória e de pacientes com doença pulmonar obstrutiva crónica (DPOC e bronquiectasias estáveis. Métodos: Foram avaliadas 21 amostras de indivíduos sem doença pulmonar submetidos a processos cirúrgicos, 10 amostras de pacientes com DPOC e 16 amostras de pacientes com bronquiectasias quanto ao transporte mucociliar (TMC, deslocamento na máquina simuladora de tosse (MST e ângulo de contacto (AC. Resultados: Maior TMC das amostras de indivíduos sem doença respiratória (1,0

  5. Self-Biased Differential Rectifier with Enhanced Dynamic Range for Wireless Powering

    KAUST Repository

    Ouda, Mahmoud H.; Khalil, Waleed; Salama, Khaled N.

    2016-01-01

    A self-biased, cross-coupled, differential rectifier is proposed with enhanced power-conversion efficiency over an extended range of input power. A prototype is designed for UHF 433MHz RF power-harvesting applications and is implemented using 0.18μm

  6. A Self-Biased Active Voltage Doubler for Energy Harvesting Systems

    KAUST Repository

    Tayyab, Umais

    2017-12-03

    An active voltage doubler utilizing a single supply op-amp for energy harvesting system is presented. The proposed doubler is used for rectification process to achieve both acceptably high power conversion efficiency (PCE) and large rectified DC voltage. The incorporated op-amp is self-biased, meaning no external supply is needed but rather it uses part of the harvested energy for its biasing. The proposed active doubler achieves maximum power conversion efficiency (PCE) of 61.7% for a 200 Hz sinusoidal input of 0.8 V for a 20 K load resistor. This efficiency is 2 times more when compared with the passive voltage doubler. The rectified DC voltage is almost 2 times more than conventional passive doubler. The relation between PCE and the load resistor is also presented. The proposed active voltage doubler is designed and simulated in LF 0.15 μm CMOS process technology using Cadence virtuoso tool.

  7. "Spiritual but not religious": Cognition, schizotypy, and conversion in alternative beliefs.

    Science.gov (United States)

    Willard, Aiyana K; Norenzayan, Ara

    2017-08-01

    The spiritual but not religious (SBNR) are a growing population in secularizing societies. Yet, we know little about the underlying psychology of this group or their belief profile. Based on an individual difference approach, we address this knowledge gap by comparing SBNR with religious and non-religious participants. In a sample of Americans (n=1013), we find that the SBNR differ from non-religious and religious participants in a number of ways. SBNR participants are more likely to hold paranormal beliefs and to have an experiential relationship to the supernatural (e.g. have mystical experiences and feelings of universal connectedness), but are similar to religious participants in their profile of cognitive biases. SBNR participants score higher on measures of schizotypy than the religious or non-religious. Reported conversions from one group (religious, SBNR, or non-religious) to another since childhood corresponds with predictable differences in cognitive biases, with dualism predicting conversion to religion and schizotypy predicting conversion to SBNR. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Subjectivities in the Sandbox: Discovering Biases through Visual Memo Writing

    Science.gov (United States)

    Lisi, Bethany

    2016-01-01

    Having insider status at an organization under study can present a researcher with benefits and challenges. Insider researchers may have access to honest dialogue with study participants but may also be vulnerable to uncomfortable conversations and organizational conflicts. Insider researchers also have to contend with their own biases they bring…

  9. The effect of framing on surrogate optimism bias: A simulation study.

    Science.gov (United States)

    Patel, Dev; Cohen, Elan D; Barnato, Amber E

    2016-04-01

    To explore the effect of emotion priming and physician communication behaviors on optimism bias. We conducted a 5 × 2 between-subject randomized factorial experiment using a Web-based interactive video designed to simulate a family meeting for a critically ill spouse/parent. Eligibility included age at least 35 years and self-identifying as the surrogate for a spouse/parent. The primary outcome was the surrogate's election of code status. We defined optimism bias as the surrogate's estimate of prognosis with cardiopulmonary resuscitation (CPR) > their recollection of the physician's estimate. Of 373 respondents, 256 (69%) logged in and were randomized and 220 (86%) had nonmissing data for prognosis. Sixty-seven (30%) of 220 overall and 56 of (32%) 173 with an accurate recollection of the physician's estimate had optimism bias. Optimism bias correlated with choosing CPR (P optimism bias. Framing the decision as the patient's vs the surrogate's (25% vs 36%, P = .066) and describing the alternative to CPR as "allow natural death" instead of "do not resuscitate" (25% vs 37%, P = .035) decreased optimism bias. Framing of CPR choice during code status conversations may influence surrogates' optimism bias. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Bias against research on gender bias.

    Science.gov (United States)

    Cislak, Aleksandra; Formanowicz, Magdalena; Saguy, Tamar

    2018-01-01

    The bias against women in academia is a documented phenomenon that has had detrimental consequences, not only for women, but also for the quality of science. First, gender bias in academia affects female scientists, resulting in their underrepresentation in academic institutions, particularly in higher ranks. The second type of gender bias in science relates to some findings applying only to male participants, which produces biased knowledge. Here, we identify a third potentially powerful source of gender bias in academia: the bias against research on gender bias. In a bibliometric investigation covering a broad range of social sciences, we analyzed published articles on gender bias and race bias and established that articles on gender bias are funded less often and published in journals with a lower Impact Factor than articles on comparable instances of social discrimination. This result suggests the possibility of an underappreciation of the phenomenon of gender bias and related research within the academic community. Addressing this meta-bias is crucial for the further examination of gender inequality, which severely affects many women across the world.

  11. A 13.56 MHz CMOS Active Rectifier With Switched-Offset and Compensated Biasing for Biomedical Wireless Power Transfer Systems.

    Science.gov (United States)

    Yan Lu; Wing-Hung Ki

    2014-06-01

    A full-wave active rectifier switching at 13.56 MHz with compensated bias current for a wide input range for wirelessly powered high-current biomedical implants is presented. The four diodes of a conventional passive rectifier are replaced by two cross-coupled PMOS transistors and two comparator- controlled NMOS switches to eliminate diode voltage drops such that high voltage conversion ratio and power conversion efficiency could be achieved even at low AC input amplitude |VAC|. The comparators are implemented with switched-offset biasing to compensate for the delays of active diodes and to eliminate multiple pulsing and reverse current. The proposed rectifier uses a modified CMOS peaking current source with bias current that is quasi-inversely proportional to the supply voltage to better control the reverse current over a wide AC input range (1.5 to 4 V). The rectifier was fabricated in a standard 0.35 μm CMOS N-well process with active area of 0.0651 mm(2). For the proposed rectifier measured at |VAC| = 3.0 V, the voltage conversion ratios are 0.89 and 0.93 for RL=500 Ω and 5 kΩ, respectively, and the measured power conversion efficiencies are 82.2% to 90.1% with |VAC| ranges from 1.5 to 4 V for RL=500 Ω.

  12. Self-Biased Differential Rectifier with Enhanced Dynamic Range for Wireless Powering

    KAUST Repository

    Ouda, Mahmoud H.

    2016-08-29

    A self-biased, cross-coupled, differential rectifier is proposed with enhanced power-conversion efficiency over an extended range of input power. A prototype is designed for UHF 433MHz RF power-harvesting applications and is implemented using 0.18μm CMOS technology. The proposed rectifier architecture is compared to the conventional cross-coupled rectifier. It demonstrates an improvement of more than 40% in the rectifier power conversion efficiency (PCE) and an input power range extension of more than 50% relative to the conventional crosscoupled rectifier. A sensitivity of -15.2dBm (30μW) input power for 1V output voltage and a peak power-conversion efficiency of 65% are achieved for a 50kω load. © 2004-2012 IEEE.

  13. Codon Bias Patterns of E. coli's Interacting Proteins.

    Directory of Open Access Journals (Sweden)

    Maddalena Dilucca

    Full Text Available Synonymous codons, i.e., DNA nucleotide triplets coding for the same amino acid, are used differently across the variety of living organisms. The biological meaning of this phenomenon, known as codon usage bias, is still controversial. In order to shed light on this point, we propose a new codon bias index, CompAI, that is based on the competition between cognate and near-cognate tRNAs during translation, without being tuned to the usage bias of highly expressed genes. We perform a genome-wide evaluation of codon bias for E.coli, comparing CompAI with other widely used indices: tAI, CAI, and Nc. We show that CompAI and tAI capture similar information by being positively correlated with gene conservation, measured by the Evolutionary Retention Index (ERI, and essentiality, whereas, CAI and Nc appear to be less sensitive to evolutionary-functional parameters. Notably, the rate of variation of tAI and CompAI with ERI allows to obtain sets of genes that consistently belong to specific clusters of orthologous genes (COGs. We also investigate the correlation of codon bias at the genomic level with the network features of protein-protein interactions in E.coli. We find that the most densely connected communities of the network share a similar level of codon bias (as measured by CompAI and tAI. Conversely, a small difference in codon bias between two genes is, statistically, a prerequisite for the corresponding proteins to interact. Importantly, among all codon bias indices, CompAI turns out to have the most coherent distribution over the communities of the interactome, pointing to the significance of competition among cognate and near-cognate tRNAs for explaining codon usage adaptation. Notably, CompAI may potentially correlate with translation speed measurements, by accounting for the specific delay induced by wobble-pairing between codons and anticodons.

  14. Efficiency enhancement using voltage biasing for ferroelectric polarization in dye-sensitized solar cells

    Science.gov (United States)

    Kim, Sangmo; Song, Myoung Geun; Bark, Chung Wung

    2018-01-01

    Dye-sensitized solar cells (DSSCs) are one of the most promising third generation solar cells that have been extensively researched over the past decade as alternative to silicon-based solar cells, due to their low production cost and high energy-conversion efficiency. In general, a DSSC consists of a transparent electrode, a counter electrode, and an electrolyte such as dye. To achieve high power-conversion efficiency in cells, many research groups have focused their efforts on developing efficient dyes for liquid electrolytes. In this work, we report on the photovoltaic properties of DSSCs fabricated using a mixture of TiO2 with nanosized Fe-doped bismuth lanthanum titanate (nFe-BLT) powder). Firstly, nFe-BLT powders were prepared using a high-energy ball milling process and then, TiO2 and nFe-BLT powders were stoichiometrically blended. Direct current (DC) bias of 20 MV/m was applied to lab-made DSSCs. With the optimal concentration of nFe-BLT doped in the electrode, their light-to-electricity conversion efficiency could be improved by ∼64% compared with DSSCs where no DC bias was applied.

  15. Specific biases for identifying facial expression of emotion in children and adolescents with conversion disorders.

    Science.gov (United States)

    Kozlowska, Kasia; Brown, Kerri J; Palmer, Donna M; Williams, Lea M

    2013-04-01

    This study aimed to assess how children and adolescents with conversion disorders identify universal facial expressions of emotion and to determine whether identification of emotion in faces relates to subjective emotional distress. Fifty-seven participants (41 girls and 16 boys) aged 8.5 to 18 years with conversion disorders and 57 age- and sex-matched healthy controls completed a computerized task in which their accuracy and reaction times for identifying facial expressions were recorded. To isolate the effect of individual emotional expressions, participants' reaction times for each emotion (fear, anger, sadness, disgust, and happiness) were subtracted from their reaction times for the neutral control face. Participants also completed self-report measures of subjective emotional distress. Children/Adolescents with conversion disorders showed faster reaction times for identifying expressions of sadness (t(112) = -2.2, p = .03; 444 [609] versus 713 [695], p = .03) and slower reactions times for happy expressions (t(99.3) = 2.28, p ≤ .024; -33 [35] versus 174 [51], p = .024), compared with controls (F(33.75, 419.81) = 3.76, p .018). There were also no differences in identification accuracy for any emotion (p > .82). The observation of faster reaction times to sad faces in children and adolescents with conversion disorders suggests increased vigilance and motor readiness to emotional signals that are potential threats to self or to close others. These effects may occur before conscious processing.

  16. Early adaptive developments of Pseudomonas aeruginosa after the transition from life in the environment to persistent colonization in the airways of human cystic fibrosis hosts

    DEFF Research Database (Denmark)

    Rau, Martin Holm; Hansen, Susse Kirkelund; Johansen, H. K.

    2010-01-01

    Pseudomonas aeruginosa is an opportunistic pathogen ubiquitous to the natural environment but with the capability of moving to the host environment. Long-term infection of the airways of cystic fibrosis patients is associated with extensive genetic adaptation of P. aeruginosa, and we have studied...... cases of the initial stages of infection in order to characterize the early adaptive processes in the colonizing bacteria. A combination of global gene expression analysis and phenotypic characterization of longitudinal isolates from cystic fibrosis patients revealed well-known characteristics...... such as conversion to a mucoid phenotype by mucA mutation and increased antibiotic resistance by nfxB mutation. Additionally, upregulation of the atu operon leading to enhanced growth on leucine provides a possible example of metabolic optimization. A detailed investigation of the mucoid phenotype uncovered profound...

  17. Comparative Genomics of Burkholderia singularis sp. nov., a Low G+C Content, Free-Living Bacterium That Defies Taxonomic Dissection of the Genus Burkholderia

    Directory of Open Access Journals (Sweden)

    Peter Vandamme

    2017-09-01

    Full Text Available Four Burkholderia pseudomallei-like isolates of human clinical origin were examined by a polyphasic taxonomic approach that included comparative whole genome analyses. The results demonstrated that these isolates represent a rare and unusual, novel Burkholderia species for which we propose the name B. singularis. The type strain is LMG 28154T (=CCUG 65685T. Its genome sequence has an average mol% G+C content of 64.34%, which is considerably lower than that of other Burkholderia species. The reduced G+C content of strain LMG 28154T was characterized by a genome wide AT bias that was not due to reduced GC-biased gene conversion or reductive genome evolution, but might have been caused by an altered DNA base excision repair pathway. B. singularis can be differentiated from other Burkholderia species by multilocus sequence analysis, MALDI-TOF mass spectrometry and a distinctive biochemical profile that includes the absence of nitrate reduction, a mucoid appearance on Columbia sheep blood agar, and a slowly positive oxidase reaction. Comparisons with publicly available whole genome sequences demonstrated that strain TSV85, an Australian water isolate, also represents the same species and therefore, to date, B. singularis has been recovered from human or environmental samples on three continents.

  18. Comparative Genomics of Burkholderia singularis sp. nov., a Low G+C Content, Free-Living Bacterium That Defies Taxonomic Dissection of the Genus Burkholderia

    Science.gov (United States)

    Vandamme, Peter; Peeters, Charlotte; De Smet, Birgit; Price, Erin P.; Sarovich, Derek S.; Henry, Deborah A.; Hird, Trevor J.; Zlosnik, James E. A.; Mayo, Mark; Warner, Jeffrey; Baker, Anthony; Currie, Bart J.; Carlier, Aurélien

    2017-01-01

    Four Burkholderia pseudomallei-like isolates of human clinical origin were examined by a polyphasic taxonomic approach that included comparative whole genome analyses. The results demonstrated that these isolates represent a rare and unusual, novel Burkholderia species for which we propose the name B. singularis. The type strain is LMG 28154T (=CCUG 65685T). Its genome sequence has an average mol% G+C content of 64.34%, which is considerably lower than that of other Burkholderia species. The reduced G+C content of strain LMG 28154T was characterized by a genome wide AT bias that was not due to reduced GC-biased gene conversion or reductive genome evolution, but might have been caused by an altered DNA base excision repair pathway. B. singularis can be differentiated from other Burkholderia species by multilocus sequence analysis, MALDI-TOF mass spectrometry and a distinctive biochemical profile that includes the absence of nitrate reduction, a mucoid appearance on Columbia sheep blood agar, and a slowly positive oxidase reaction. Comparisons with publicly available whole genome sequences demonstrated that strain TSV85, an Australian water isolate, also represents the same species and therefore, to date, B. singularis has been recovered from human or environmental samples on three continents. PMID:28932212

  19. Self-reverse-biased solar panel optical receiver for simultaneous visible light communication and energy harvesting.

    Science.gov (United States)

    Shin, Won-Ho; Yang, Se-Hoon; Kwon, Do-Hoon; Han, Sang-Kook

    2016-10-31

    We propose a self-reverse-biased solar panel optical receiver for energy harvesting and visible light communication. Since the solar panel converts an optical component into an electrical component, it provides both energy harvesting and communication. The signal component can be separated from the direct current component, and these components are used for communication and energy harvesting. We employed a self-reverse-biased receiver circuit to improve the communication and energy harvesting performance. The reverse bias on the solar panel improves the responsivity and response time. The proposed system achieved 17.05 mbps discrete multitone transmission with a bit error rate of 1.1 x 10-3 and enhanced solar energy conversion efficiency.

  20. Strong mechanically induced effects in DC current-biased suspended Josephson junctions

    Science.gov (United States)

    McDermott, Thomas; Deng, Hai-Yao; Isacsson, Andreas; Mariani, Eros

    2018-01-01

    Superconductivity is a result of quantum coherence at macroscopic scales. Two superconductors separated by a metallic or insulating weak link exhibit the AC Josephson effect: the conversion of a DC voltage bias into an AC supercurrent. This current may be used to activate mechanical oscillations in a suspended weak link. As the DC-voltage bias condition is remarkably difficult to achieve in experiments, here we analyze theoretically how the Josephson effect can be exploited to activate and detect mechanical oscillations in the experimentally relevant condition with purely DC current bias. We unveil how changing the strength of the electromechanical coupling results in two qualitatively different regimes showing dramatic effects of the oscillations on the DC-voltage characteristic of the device. These include the appearance of Shapiro-type plateaus for weak coupling and a sudden mechanically induced retrapping for strong coupling. Our predictions, measurable in state-of-the-art experimental setups, allow the determination of the frequency and quality factor of the resonator using DC only techniques.

  1. Positively Biased Processing of Mother's Emotions Predicts Children's Social and Emotional Functioning.

    Science.gov (United States)

    Donohue, Meghan Rose; Goodman, Sherryl H; Tully, Erin C

    Risk for internalizing problems and social skills deficits likely emerges in early childhood when emotion processing and social competencies are developing. Positively biased processing of social information is typical during early childhood and may be protective against poorer psychosocial outcomes. We tested the hypothesis that young children with relatively less positively biased attention to, interpretations of, and attributions for their mother's emotions would exhibit poorer prosocial skills and more internalizing problems. A sample of 4- to 6-year-old children ( N =82) observed their mothers express happiness, sadness and anger during a simulated emotional phone conversation. Children's attention to their mother when she expressed each emotion was rated from video. Immediately following the phone conversation, children were asked questions about the conversation to assess their interpretations of the intensity of mother's emotions and misattributions of personal responsibility for her emotions. Children's prosocial skills and internalizing problems were assessed using mother-report rating scales. Interpretations of mother's positive emotions as relatively less intense than her negative emotions, misattributions of personal responsibility for her negative emotions, and lack of misattributions of personal responsibility for her positive emotions were associated with poorer prosocial skills. Children who attended relatively less to mother's positive than her negative emotions had higher levels of internalizing problems. These findings suggest that children's attention to, interpretations of, and attributions for their mother's emotions may be important targets of early interventions for preventing prosocial skills deficits and internalizing problems.

  2. Dynamic in vivo mutations within the ica operon during persistence of Staphylococcus aureus in the airways of cystic fibrosis patients.

    Directory of Open Access Journals (Sweden)

    Bianca Schwartbeck

    2016-11-01

    Full Text Available Cystic fibrosis (CF is associated with chronic bacterial airway infections leading to lung insufficiency and decreased life expectancy. Staphylococcus aureus is one of the most prevalent pathogens isolated from the airways of CF patients. Mucoid colony morphology has been described for Pseudomonas aeruginosa, the most common pathogen in CF, but not for S. aureus. From the airways of 8 of 313 CF patients (2.5% mucoid S. aureus isolates (n = 115 were cultured with a mean persistence of 29 months (range 1 month, 126 months. In contrast to non-mucoid S. aureus, mucoid isolates were strong biofilm formers. The upstream region of the ica operon, which encodes the proteins responsible for the synthesis of the polysaccharide intercellular adhesin (PIA, of mucoid isolates was sequenced. Spa-types of mucoid and non-mucoid strains were identical, but differed between patients. Mucoid isolates carried a 5 bp deletion in the intergenic region between icaR and icaA. During long-term persistence, from two patients subsequent non-mucoid isolates (n = 12 with 5 bp deletions were cultured, which did not produce biofilm. Sequencing of the entire ica operon identified compensatory mutations in various ica-genes including icaA (n = 7, icaD (n = 3 and icaC (n = 2. Six sequential isolates of each of these two patients with non-mucoid and mucoid phenotypes were subjected to whole genome sequencing revealing a very close relationship of the individual patient's isolates. Transformation of strains with vectors expressing the respective wild-type genes restored mucoidy. In contrast to the non-mucoid phenotype, mucoid strains were protected against neutrophilic killing and survived better under starvation conditions. In conclusion, the special conditions present in CF airways seem to facilitate ongoing mutations in the ica operon during S. aureus persistence.

  3. Effect of top gate bias on photocurrent and negative bias illumination stress instability in dual gate amorphous indium-gallium-zinc oxide thin-film transistor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eunji; Chowdhury, Md Delwar Hossain; Park, Min Sang; Jang, Jin, E-mail: jjang@khu.ac.kr [Advanced Display Research Center and Department of Information Display, Kyung Hee University, Seoul 130-701 (Korea, Republic of)

    2015-12-07

    We have studied the effect of top gate bias (V{sub TG}) on the generation of photocurrent and the decay of photocurrent for back channel etched inverted staggered dual gate structure amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film-transistors. Upon 5 min of exposure of 365 nm wavelength and 0.7 mW/cm{sup 2} intensity light with negative bottom gate bias, the maximum photocurrent increases from 3.29 to 322 pA with increasing the V{sub TG} from −15 to +15 V. By changing V{sub TG} from negative to positive, the Fermi level (E{sub F}) shifts toward conduction band edge (E{sub C}), which substantially controls the conversion of neutral vacancy to charged one (V{sub O} → V{sub O}{sup +}/V{sub O}{sup 2+} + e{sup −}/2e{sup −}), peroxide (O{sub 2}{sup 2−}) formation or conversion of ionized interstitial (O{sub i}{sup 2−}) to neutral interstitial (O{sub i}), thus electron concentration at conduction band. With increasing the exposure time, more carriers are generated, and thus, maximum photocurrent increases until being saturated. After negative bias illumination stress, the transfer curve shows −2.7 V shift at V{sub TG} = −15 V, which gradually decreases to −0.42 V shift at V{sub TG} = +15 V. It clearly reveals that the position of electron quasi-Fermi level controls the formation of donor defects (V{sub O}{sup +}/V{sub O}{sup 2+}/O{sub 2}{sup 2−}/O{sub i}) and/or hole trapping in the a-IGZO /interfaces.

  4. The mediating role of state maladaptive emotion regulation in the relation between social anxiety symptoms and self-evaluation bias.

    Science.gov (United States)

    Sarfan, Laurel D; Cody, Meghan W; Clerkin, Elise M

    2018-03-16

    Although social anxiety symptoms are robustly linked to biased self-evaluations across time, the mechanisms of this relation remain unclear. The present study tested three maladaptive emotion regulation strategies - state post-event processing, state experiential avoidance, and state expressive suppression - as potential mediators of this relation. Undergraduate participants (N = 88; 61.4% Female) rated their social skill in an impromptu conversation task and then returned to the laboratory approximately two days later to evaluate their social skill in the conversation again. Consistent with expectations, state post-event processing and state experiential avoidance mediated the relation between social anxiety symptoms and worsening self-evaluations of social skill (controlling for research assistant evaluations), particularly for positive qualities (e.g. appeared confident, demonstrated social skill). State expressive suppression did not mediate the relation between social anxiety symptoms and changes in self-evaluation bias across time. These findings highlight the role that spontaneous, state experiential avoidance and state post-event processing may play in the relation between social anxiety symptoms and worsening self-evaluation biases of social skill across time.

  5. A Low Power 2.4 GHz CMOS Mixer Using Forward Body Bias Technique for Wireless Sensor Network

    Science.gov (United States)

    Yin, C. J.; Murad, S. A. Z.; Harun, A.; Ramli, M. M.; Zulkifli, T. Z. A.; Karim, J.

    2018-03-01

    Wireless sensor network (WSN) is a highly-demanded application since the evolution of wireless generation which is often used in recent communication technology. A radio frequency (RF) transceiver in WSN should have a low power consumption to support long operating times of mobile devices. A down-conversion mixer is responsible for frequency translation in a receiver. By operating a down-conversion mixer at a low supply voltage, the power consumed by WSN receiver can be greatly reduced. This paper presents a development of low power CMOS mixer using forward body bias technique for wireless sensor network. The proposed mixer is implemented using CMOS 0.13 μm Silterra technology. The forward body bias technique is adopted to obtain low power consumption. The simulation results indicate that a low power consumption of 0.91 mW is achieved at 1.6 V supply voltage. Moreover, the conversion gain (CG) of 21.83 dB, the noise figure (NF) of 16.51 dB and the input-referred third-order intercept point (IIP3) of 8.0 dB at 2.4 GHz are obtained. The proposed mixer is suitable for wireless sensor network.

  6. Reference Materials for Calibration of Analytical Biases in Quantification of DNA Methylation.

    Science.gov (United States)

    Yu, Hannah; Hahn, Yoonsoo; Yang, Inchul

    2015-01-01

    Most contemporary methods for the quantification of DNA methylation employ bisulfite conversion and PCR amplification. However, many reports have indicated that bisulfite-mediated PCR methodologies can result in inaccurate measurements of DNA methylation owing to amplification biases. To calibrate analytical biases in quantification of gene methylation, especially those that arise during PCR, we utilized reference materials that represent exact bisulfite-converted sequences with 0% and 100% methylation status of specific genes. After determining relative quantities using qPCR, pairs of plasmids were gravimetrically mixed to generate working standards with predefined DNA methylation levels at 10% intervals in terms of mole fractions. The working standards were used as controls to optimize the experimental conditions and also as calibration standards in melting-based and sequencing-based analyses of DNA methylation. Use of the reference materials enabled precise characterization and proper calibration of various biases during PCR and subsequent methylation measurement processes, resulting in accurate measurements.

  7. Workplace ageism: discovering hidden bias.

    Science.gov (United States)

    Malinen, Sanna; Johnston, Lucy

    2013-01-01

    BACKGROUND/STUDY CONTEXT: Research largely shows no performance differences between older and younger employees, or that older workers even outperform younger employees, yet negative attitudes towards older workers can underpin discrimination. Unfortunately, traditional "explicit" techniques for assessing attitudes (i.e., self-report measures) have serious drawbacks. Therefore, using an approach that is novel to organizational contexts, the authors supplemented explicit with implicit (indirect) measures of attitudes towards older workers, and examined the malleability of both. This research consists of two studies. The authors measured self-report (explicit) attitudes towards older and younger workers with a survey, and implicit attitudes with a reaction-time-based measure of implicit associations. In addition, to test whether attitudes were malleable, the authors measured attitudes before and after a mental imagery intervention, where the authors asked participants in the experimental group to imagine respected and valued older workers from their surroundings. Negative, stable implicit attitudes towards older workers emerged in two studies. Conversely, explicit attitudes showed no age bias and were more susceptible to change intervention, such that attitudes became more positive towards older workers following the experimental manipulation. This research demonstrates the unconscious nature of bias against older workers, and highlights the utility of implicit attitude measures in the context of the workplace. In the current era of aging workforce and skill shortages, implicit measures may be necessary to illuminate hidden workplace ageism.

  8. Requirements' Role in Mobilizing and Enabling Design Conversation

    Science.gov (United States)

    Bergman, Mark

    Requirements play a critical role in a design conversation of systems and products. Product and system design exists at the crossroads of problems, solutions and requirements. Requirements contextualize problems and solutions, pointing the way to feasible outcomes. These are captured with models and detailed specifications. Still, stakeholders need to be able to understand one-another using shared design representations in order to mobilize bias and transform knowledge towards legitimized, desired results. Many modern modeling languages, including UML, as well as detailed, logic-based specifications are beyond the comprehension of key stakeholders. Hence, they inhibit, rather than promote design conversation. Improved design boundary objects (DBO), especially design requirements boundary objects (DRBO), need to be created and refined to improve the communications between principals. Four key features of design boundary objects that improve and promote design conversation are discussed in detail. A systems analysis and design case study is presented which demonstrates these features in action. It describes how a small team of analysts worked with key stakeholders to mobilize and guide a complex system design discussion towards an unexpected, yet desired outcome within a short time frame.

  9. Sympathetic bias.

    Science.gov (United States)

    Levy, David M; Peart, Sandra J

    2008-06-01

    We wish to deal with investigator bias in a statistical context. We sketch how a textbook solution to the problem of "outliers" which avoids one sort of investigator bias, creates the temptation for another sort. We write down a model of the approbation seeking statistician who is tempted by sympathy for client to violate the disciplinary standards. We give a simple account of one context in which we might expect investigator bias to flourish. Finally, we offer tentative suggestions to deal with the problem of investigator bias which follow from our account. As we have given a very sparse and stylized account of investigator bias, we ask what might be done to overcome this limitation.

  10. Bias modification training can alter approach bias and chocolate consumption.

    Science.gov (United States)

    Schumacher, Sophie E; Kemps, Eva; Tiggemann, Marika

    2016-01-01

    Recent evidence has demonstrated that bias modification training has potential to reduce cognitive biases for attractive targets and affect health behaviours. The present study investigated whether cognitive bias modification training could be applied to reduce approach bias for chocolate and affect subsequent chocolate consumption. A sample of 120 women (18-27 years) were randomly assigned to an approach-chocolate condition or avoid-chocolate condition, in which they were trained to approach or avoid pictorial chocolate stimuli, respectively. Training had the predicted effect on approach bias, such that participants trained to approach chocolate demonstrated an increased approach bias to chocolate stimuli whereas participants trained to avoid such stimuli showed a reduced bias. Further, participants trained to avoid chocolate ate significantly less of a chocolate muffin in a subsequent taste test than participants trained to approach chocolate. Theoretically, results provide support for the dual process model's conceptualisation of consumption as being driven by implicit processes such as approach bias. In practice, approach bias modification may be a useful component of interventions designed to curb the consumption of unhealthy foods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Combination of biased forecasts: Bias correction or bias based weights?

    OpenAIRE

    Wenzel, Thomas

    1999-01-01

    Most of the literature on combination of forecasts deals with the assumption of unbiased individual forecasts. Here, we consider the case of biased forecasts and discuss two different combination techniques resulting in an unbiased forecast. On the one hand we correct the individual forecasts, and on the other we calculate bias based weights. A simulation study gives some insight in the situations where we should use the different methods.

  12. Estimation bias and bias correction in reduced rank autoregressions

    DEFF Research Database (Denmark)

    Nielsen, Heino Bohn

    2017-01-01

    This paper characterizes the finite-sample bias of the maximum likelihood estimator (MLE) in a reduced rank vector autoregression and suggests two simulation-based bias corrections. One is a simple bootstrap implementation that approximates the bias at the MLE. The other is an iterative root...

  13. Analysis of 62 hybrid assembled human Y chromosomes exposes rapid structural changes and high rates of gene conversion.

    Directory of Open Access Journals (Sweden)

    Laurits Skov

    2017-08-01

    Full Text Available The human Y-chromosome does not recombine across its male-specific part and is therefore an excellent marker of human migrations. It also plays an important role in male fertility. However, its evolution is difficult to fully understand because of repetitive sequences, inverted repeats and the potentially large role of gene conversion. Here we perform an evolutionary analysis of 62 Y-chromosomes of Danish descent sequenced using a wide range of library insert sizes and high coverage, thus allowing large regions of these chromosomes to be well assembled. These include 17 father-son pairs, which we use to validate variation calling. Using a recent method that can integrate variants based on both mapping and de novo assembly, we genotype 10898 SNVs and 2903 indels (max length of 27241 bp in our sample and show by father-son concordance and experimental validation that the non-recurrent SNP and indel variation on the Y chromosome tree is called very accurately. This includes variation called in a 0.9 Mb centromeric heterochromatic region, which is by far the most variable in the Y chromosome. Among the variation is also longer sequence-stretches not present in the reference genome but shared with the chimpanzee Y chromosome. We analyzed 2.7 Mb of large inverted repeats (palindromes for variation patterns among the two palindrome arms and identified 603 mutation and 416 gene conversions events. We find clear evidence for GC-biased gene conversion in the palindromes (and a balancing AT mutation bias, but irrespective of this, also a strong bias towards gene conversion towards the ancestral state, suggesting that palindromic gene conversion may alleviate Muller's ratchet. Finally, we also find a large number of large-scale gene duplications and deletions in the palindromic regions (at least 24 and find that such events can consist of complex combinations of simultaneous insertions and deletions of long stretches of the Y chromosome.

  14. The Ugly Truth About Ourselves and Our Robot Creations: The Problem of Bias and Social Inequity.

    Science.gov (United States)

    Howard, Ayanna; Borenstein, Jason

    2017-09-21

    Recently, there has been an upsurge of attention focused on bias and its impact on specialized artificial intelligence (AI) applications. Allegations of racism and sexism have permeated the conversation as stories surface about search engines delivering job postings for well-paying technical jobs to men and not women, or providing arrest mugshots when keywords such as "black teenagers" are entered. Learning algorithms are evolving; they are often created from parsing through large datasets of online information while having truth labels bestowed on them by crowd-sourced masses. These specialized AI algorithms have been liberated from the minds of researchers and startups, and released onto the public. Yet intelligent though they may be, these algorithms maintain some of the same biases that permeate society. They find patterns within datasets that reflect implicit biases and, in so doing, emphasize and reinforce these biases as global truth. This paper describes specific examples of how bias has infused itself into current AI and robotic systems, and how it may affect the future design of such systems. More specifically, we draw attention to how bias may affect the functioning of (1) a robot peacekeeper, (2) a self-driving car, and (3) a medical robot. We conclude with an overview of measures that could be taken to mitigate or halt bias from permeating robotic technology.

  15. Positive bias is a defining characteristic of aging to the same extent as declining performance.

    Science.gov (United States)

    Simón, Teresa; Suengas, Aurora G; Ruiz-Gallego-Largo, Trinidad; Bandrés, Javier

    2013-01-01

    The aim of this study was to analyze whether one of the supposed gains of aging--positive bias--discriminates between young and older participants to the same extent as some of the losses in cognitive performance--recall and source monitoring--that come with age. Two age groups (N = 120)--young (M = 22.08, SD = 3.30) and older (M = 72.78, SD = 6.57)--carried out three tasks with varying levels of difficulty that included recall, recognition, and source monitoring using pictures, faces, and personal descriptors exchanged in a conversation as stimuli. The results of the discriminant analysis performed on 20 dependent variables indicated that six of them were key in discriminating between young and older participants. Younger participants outperformed older participants in recalling pictures, and in recognizing the descriptors exchanged in a conversation, as well as in monitoring their source. Just as important in discriminating between the two groups were the ability to recognize previously seen pictures, the likability rating they produced, and the recognition of faces with positive expressions--all superior in older participants. Thus, variables related to a positive bias--likability ratings and recognition of positive expressions--characterize the differences as a function of age as well as variables related to cognitive performance, such as recall and source monitoring. In addition, the likability ratings evoked by both pictures and faces were also significantly higher in the older participants with better cognitive performance than in those who performed poorly. This effect was not present in younger participants. The results are interpreted within the framework of socioemotional selectivity theory as evidence for a positive bias in old age. The connection between a positive bias and the maintenance of cognitive performance is also discussed.

  16. Positively Biased Processing of Mother’s Emotions Predicts Children’s Social and Emotional Functioning

    Science.gov (United States)

    Donohue, Meghan Rose; Goodman, Sherryl H.; Tully, Erin C.

    2016-01-01

    Risk for internalizing problems and social skills deficits likely emerges in early childhood when emotion processing and social competencies are developing. Positively biased processing of social information is typical during early childhood and may be protective against poorer psychosocial outcomes. We tested the hypothesis that young children with relatively less positively biased attention to, interpretations of, and attributions for their mother’s emotions would exhibit poorer prosocial skills and more internalizing problems. A sample of 4- to 6-year-old children (N=82) observed their mothers express happiness, sadness and anger during a simulated emotional phone conversation. Children’s attention to their mother when she expressed each emotion was rated from video. Immediately following the phone conversation, children were asked questions about the conversation to assess their interpretations of the intensity of mother’s emotions and misattributions of personal responsibility for her emotions. Children’s prosocial skills and internalizing problems were assessed using mother-report rating scales. Interpretations of mother’s positive emotions as relatively less intense than her negative emotions, misattributions of personal responsibility for her negative emotions, and lack of misattributions of personal responsibility for her positive emotions were associated with poorer prosocial skills. Children who attended relatively less to mother’s positive than her negative emotions had higher levels of internalizing problems. These findings suggest that children’s attention to, interpretations of, and attributions for their mother’s emotions may be important targets of early interventions for preventing prosocial skills deficits and internalizing problems. PMID:28348456

  17. Study of aerosol direct and indirect effects and auto-conversion processes over the West African monsoon region using a regional climate model

    Science.gov (United States)

    Salah, Zeinab; Shalaby, Ahmed; Steiner, Allison L.; Zakey, Ashraf S.; Gautam, Ritesh; Abdel Wahab, Mohamed M.

    2018-02-01

    This study assesses the direct and indirect effects of natural and anthropogenic aerosols (e.g., black carbon and sulfate) over West and Central Africa during the West African monsoon (WAM) period (June-July-August). We investigate the impacts of aerosols on the amount of cloudiness, the influences on the precipitation efficiency of clouds, and the associated radiative forcing (direct and indirect). Our study includes the implementation of three new formulations of auto-conversion parameterization [namely, the Beheng (BH), Tripoli and Cotton (TC) and Liu and Daum (R6) schemes] in RegCM4.4.1, besides the default model's auto-conversion scheme (Kessler). Among the new schemes, BH reduces the precipitation wet bias by more than 50% over West Africa and achieves a bias reduction of around 25% over Central Africa. Results from detailed sensitivity experiments suggest a significant path forward in terms of addressing the long-standing issue of the characteristic wet bias in RegCM. In terms of aerosol-induced radiative forcing, the impact of the various schemes is found to vary considerably (ranging from -5 to -25 W m-2).

  18. Disclosing bias in bisulfite assay: MethPrimers underestimate high DNA methylation.

    Directory of Open Access Journals (Sweden)

    Andrea Fuso

    Full Text Available Discordant results obtained in bisulfite assays using MethPrimers (PCR primers designed using MethPrimer software or assuming that non-CpGs cytosines are non methylated versus primers insensitive to cytosine methylation lead us to hypothesize a technical bias. We therefore used the two kinds of primers to study different experimental models and methylation statuses. We demonstrated that MethPrimers negatively select hypermethylated DNA sequences in the PCR step of the bisulfite assay, resulting in CpG methylation underestimation and non-CpG methylation masking, failing to evidence differential methylation statuses. We also describe the characteristics of "Methylation-Insensitive Primers" (MIPs, having degenerated bases (G/A to cope with the uncertain C/U conversion. As CpG and non-CpG DNA methylation patterns are largely variable depending on the species, developmental stage, tissue and cell type, a variable extent of the bias is expected. The more the methylome is methylated, the greater is the extent of the bias, with a prevalent effect of non-CpG methylation. These findings suggest a revision of several DNA methylation patterns so far documented and also point out the necessity of applying unbiased analyses to the increasing number of epigenomic studies.

  19. Journal bias or author bias?

    Science.gov (United States)

    Harris, Ian

    2016-01-01

    I read with interest the comment by Mark Wilson in the Indian Journal of Medical Ethics regarding bias and conflicts of interest in medical journals. Wilson targets one journal (the New England Journal of Medicine: NEJM) and one particular "scandal" to make his point that journals' decisions on publication are biased by commercial conflicts of interest (CoIs). It is interesting that he chooses the NEJM which, by his own admission, had one of the strictest CoI policies and had published widely on this topic. The feeling is that if the NEJM can be guilty, they can all be guilty.

  20. Modulation of Charge Recombination in CsPbBr3 Perovskite Films with Electrochemical Bias

    KAUST Repository

    Scheidt, Rebecca A

    2017-11-13

    The charging of mesoscopic TiO2 layer in a metal halide perovskite solar cell can influence the overall power conversion efficiency. By employing CsPbBr3 films deposited on a mesoscopic TiO2 film, we have succeeded in probing the influence of electrochemical bias on the charge carrier recombination process. The transient absorption spectroscopy experiments conducted at different applied potentials indicate a decrease in the charge carrier lifetimes of CsPbBr3 as we increase the potential from -0.6 V to + 0.6 V vs. Ag/AgCl. The charge carrier lifetime increased upon reversing the applied bias, thus indicating the reversibility of the photoresponse to charging effects. The ultrafast spectroelectrochemical experiments described here offer a convenient approach to probe the charging effects in perovskite solar cells.

  1. Modulation of Charge Recombination in CsPbBr3 Perovskite Films with Electrochemical Bias.

    Science.gov (United States)

    Scheidt, Rebecca A; Samu, Gergely F; Janáky, Csaba; Kamat, Prashant V

    2018-01-10

    The charging of a mesoscopic TiO 2 layer in a metal halide perovskite solar cell can influence the overall power conversion efficiency. By employing CsPbBr 3 films deposited on a mesoscopic TiO 2 film, we have succeeded in probing the influence of electrochemical bias on the charge carrier recombination process. The transient absorption spectroscopy experiments conducted at different applied potentials indicate a decrease in the charge carrier lifetimes of CsPbBr 3 as we increase the potential from -0.6 to +0.6 V vs Ag/AgCl. The charge carrier lifetime increased upon reversing the applied bias, thus indicating the reversibility of the photoresponse to charging effects. The ultrafast spectroelectrochemical experiments described here offer a convenient approach to probe the charging effects in perovskite solar cells.

  2. Integrated Photoelectrochemical Solar Energy Conversion and Organic Redox Flow Battery Devices

    KAUST Repository

    Li, Wenjie

    2016-09-21

    Building on regenerative photoelectrochemical solar cells and emerging electrochemical redox flow batteries (RFBs), more efficient, scalable, compact, and cost-effective hybrid energy conversion and storage devices could be realized. An integrated photoelectrochemical solar energy conversion and electrochemical storage device is developed by integrating regenerative silicon solar cells and 9,10-anthraquinone-2,7-disulfonic acid (AQDS)/1,2-benzoquinone-3,5-disulfonic acid (BQDS) RFBs. The device can be directly charged by solar light without external bias, and discharged like normal RFBs with an energy storage density of 1.15 Wh L−1 and a solar-to-output electricity efficiency (SOEE) of 1.7 % over many cycles. The concept exploits a previously undeveloped design connecting two major energy technologies and promises a general approach for storing solar energy electrochemically with high theoretical storage capacity and efficiency.

  3. Beyond assembly bias: exploring secondary halo biases for cluster-size haloes

    Science.gov (United States)

    Mao, Yao-Yuan; Zentner, Andrew R.; Wechsler, Risa H.

    2018-03-01

    Secondary halo bias, commonly known as `assembly bias', is the dependence of halo clustering on a halo property other than mass. This prediction of the Λ Cold Dark Matter cosmology is essential to modelling the galaxy distribution to high precision and interpreting clustering measurements. As the name suggests, different manifestations of secondary halo bias have been thought to originate from halo assembly histories. We show conclusively that this is incorrect for cluster-size haloes. We present an up-to-date summary of secondary halo biases of high-mass haloes due to various halo properties including concentration, spin, several proxies of assembly history, and subhalo properties. While concentration, spin, and the abundance and radial distribution of subhaloes exhibit significant secondary biases, properties that directly quantify halo assembly history do not. In fact, the entire assembly histories of haloes in pairs are nearly identical to those of isolated haloes. In general, a global correlation between two halo properties does not predict whether or not these two properties exhibit similar secondary biases. For example, assembly history and concentration (or subhalo abundance) are correlated for both paired and isolated haloes, but follow slightly different conditional distributions in these two cases. This results in a secondary halo bias due to concentration (or subhalo abundance), despite the lack of assembly bias in the strict sense for cluster-size haloes. Due to this complexity, caution must be exercised in using any one halo property as a proxy to study the secondary bias due to another property.

  4. Causal role for inverse reasoning on obsessive-compulsive symptoms: Preliminary evidence from a cognitive bias modification for interpretation bias study.

    Science.gov (United States)

    Wong, Shiu F; Grisham, Jessica R

    2017-12-01

    The inference-based approach (IBA) is a cognitive account of the genesis and maintenance of obsessive-compulsive disorder (OCD). According to the IBA, individuals with OCD are prone to using inverse reasoning, in which hypothetical causes form the basis of conclusions about reality. Several studies have provided preliminary support for an association between features of the IBA and OCD symptoms. However, there are currently no studies that have investigated the proposed causal relationship of inverse reasoning in OCD. In a non-clinical sample (N = 187), we used an interpretive cognitive bias procedure to train a bias towards using inverse reasoning (n = 64), healthy sensory-based reasoning (n = 65), or a control condition (n = 58). Participants were randomly allocated to these training conditions. This manipulation allowed us to assess whether, consistent with the IBA, inverse reasoning training increased compulsive-like behaviours and self-reported OCD symptoms. Results indicated that compared to a control condition, participants trained in inverse reasoning reported more OCD symptoms and were more avoidant of potentially contaminated objects. Moreover, change in inverse reasoning bias was a small but significant mediator of the relationship between training condition and behavioural avoidance. Conversely, training in a healthy (non-inverse) reasoning style did not have any effect on symptoms or behaviour relative to the control condition. As this study was conducted in a non-clinical sample, we were unable to generalise our findings to a clinical population. Findings generally support the IBA model by providing preliminary evidence of a causal role for inverse reasoning in OCD. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Bias and equivalence of the Strengths Use and Deficit Correction Questionnaire

    Directory of Open Access Journals (Sweden)

    Crizelle Els

    2016-11-01

    Full Text Available Orientation: For optimal outcomes, it is suggested that employees receive support from their organisation to use their strengths and improve their deficits. Employees also engage in proactive behaviour to use their strengths and improve their deficits. Following this conversation, the Strengths Use and Deficit Correction Questionnaire (SUDCO was developed. However, the cultural suitability of the SUDCO has not been confirmed. Research purpose: The purpose of this study was to examine the bias and structural equivalence of the SUDCO. Motivation for the study: In a diverse cultural context such as South Africa, it is important to establish that a similar score on a psychological test has the same psychological meaning across ethnic groups. Research design, approach and method: A cross-sectional survey design was followed to collect data among a convenience sample of 858 employees from various occupational sectors in South Africa. Main findings: Confirmatory multigroup analysis was used to test for item and construct bias. None of the items were biased, neither uniform nor non-uniform. The most restrictive model accounted for similarities in weights, intercepts and means; only residuals were different. Practical/managerial implications: The results suggest that the SUDCO is suitable for use among the major ethnic groups included in this study. These results increase the probability that future studies with the SUDCO among other ethnic groups will be unbiased and equivalent. Contribution: This study contributed to existing literature because no previous research has assessed the bias and equivalence of the SUDCO among ethnic groups in South Africa.

  6. CPI Bias in Korea

    Directory of Open Access Journals (Sweden)

    Chul Chung

    2007-12-01

    Full Text Available We estimate the CPI bias in Korea by employing the approach of Engel’s Law as suggested by Hamilton (2001. This paper is the first attempt to estimate the bias using Korean panel data, Korean Labor and Income Panel Study(KLIPS. Following Hamilton’s model with non­linear specification correction, our estimation result shows that the cumulative CPI bias over the sample period (2000-2005 was 0.7 percent annually. This CPI bias implies that about 21 percent of the inflation rate during the period can be attributed to the bias. In light of purchasing power parity, we provide an interpretation of the estimated bias.

  7. Approximate Bias Correction in Econometrics

    OpenAIRE

    James G. MacKinnon; Anthony A. Smith Jr.

    1995-01-01

    This paper discusses ways to reduce the bias of consistent estimators that are biased in finite samples. It is necessary that the bias function, which relates parameter values to bias, should be estimable by computer simulation or by some other method. If so, bias can be reduced or, in some cases that may not be unrealistic, even eliminated. In general, several evaluations of the bias function will be required to do this. Unfortunately, reducing bias may increase the variance, or even the mea...

  8. Integrated Photoelectrochemical Solar Energy Conversion and Organic Redox Flow Battery Devices.

    Science.gov (United States)

    Li, Wenjie; Fu, Hui-Chun; Li, Linsen; Cabán-Acevedo, Miguel; He, Jr-Hau; Jin, Song

    2016-10-10

    Building on regenerative photoelectrochemical solar cells and emerging electrochemical redox flow batteries (RFBs), more efficient, scalable, compact, and cost-effective hybrid energy conversion and storage devices could be realized. An integrated photoelectrochemical solar energy conversion and electrochemical storage device is developed by integrating regenerative silicon solar cells and 9,10-anthraquinone-2,7-disulfonic acid (AQDS)/1,2-benzoquinone-3,5-disulfonic acid (BQDS) RFBs. The device can be directly charged by solar light without external bias, and discharged like normal RFBs with an energy storage density of 1.15 Wh L -1 and a solar-to-output electricity efficiency (SOEE) of 1.7 % over many cycles. The concept exploits a previously undeveloped design connecting two major energy technologies and promises a general approach for storing solar energy electrochemically with high theoretical storage capacity and efficiency. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Beyond attentional bias: a perceptual bias in a dot-probe task.

    Science.gov (United States)

    Bocanegra, Bruno R; Huijding, Jorg; Zeelenberg, René

    2012-12-01

    Previous dot-probe studies indicate that threat-related face cues induce a bias in spatial attention. Independently of spatial attention, a recent psychophysical study suggests that a bilateral fearful face cue improves low spatial-frequency perception (LSF) and impairs high spatial-frequency perception (HSF). Here, we combine these separate lines of research within a single dot-probe paradigm. We found that a bilateral fearful face cue, compared with a bilateral neutral face cue, speeded up responses to LSF targets and slowed down responses to HSF targets. This finding is important, as it shows that emotional cues in dot-probe tasks not only bias where information is preferentially processed (i.e., an attentional bias in spatial location), but also bias what type of information is preferentially processed (i.e., a perceptual bias in spatial frequency). PsycINFO Database Record (c) 2012 APA, all rights reserved.

  10. Simulating publication bias

    DEFF Research Database (Denmark)

    Paldam, Martin

    is censoring: selection by the size of estimate; SR3 selects the optimal combination of fit and size; and SR4 selects the first satisficing result. The last four SRs are steered by priors and result in bias. The MST and the FAT-PET have been developed for detection and correction of such bias. The simulations......Economic research typically runs J regressions for each selected for publication – it is often selected as the ‘best’ of the regressions. The paper examines five possible meanings of the word ‘best’: SR0 is ideal selection with no bias; SR1 is polishing: selection by statistical fit; SR2...... are made by data variation, while the model is the same. It appears that SR0 generates narrow funnels much at odds with observed funnels, while the other four funnels look more realistic. SR1 to SR4 give the mean a substantial bias that confirms the prior causing the bias. The FAT-PET MRA works well...

  11. A study on investors’ personality characteristics and behavioral biases: Conservatism bias and availability bias in the Tehran Stock Exchange

    Directory of Open Access Journals (Sweden)

    Mahmoud Moradi

    2013-04-01

    Full Text Available Most economic and finance theories are based on the assumption that during economic decision making, people would act totally rational and consider all available information. Nevertheless, behavioral finance focuses on studying of the role of psychological factors on economic participants’ behavior. The study shows that in real-world environment, people are influenced by emotional and cognitive errors and may make irrational financial decisions. In many cases, the participants of financial markets are not aware of their talents for error in decision making, so they are dissatisfied with their investments by considering some behavioral biases decisions. These decisions may often yield undesirable outcomes, which could influence economy, significantly. This paper presents a survey on the relationship between personality dimensions with behavioral biases and availability bias among investment managers in the Tehran Stock Exchange using SPSS software, descriptive and inferential statistics. The necessary data are collected through questionnaire and they are analyzed using some statistical tests. The preliminary results indicate that there is a relationship between personality dimensions and behavioral biases like conservatism bias and availability bias among the investors in the Tehran Stock Exchange.

  12. Media bias under direct and indirect government control: when is the bias smaller?

    OpenAIRE

    Abhra Roy

    2015-01-01

    We present an analytical framework to compare media bias under direct and indirect government control. In this context, we show that direct control can lead to a smaller bias and higher welfare than indirect control. We further show that the size of the advertising market affects media bias only under direct control. Media bias, under indirect control, is not affected by the size of the advertising market.

  13. Large-scale galaxy bias

    Science.gov (United States)

    Desjacques, Vincent; Jeong, Donghui; Schmidt, Fabian

    2018-02-01

    This review presents a comprehensive overview of galaxy bias, that is, the statistical relation between the distribution of galaxies and matter. We focus on large scales where cosmic density fields are quasi-linear. On these scales, the clustering of galaxies can be described by a perturbative bias expansion, and the complicated physics of galaxy formation is absorbed by a finite set of coefficients of the expansion, called bias parameters. The review begins with a detailed derivation of this very important result, which forms the basis of the rigorous perturbative description of galaxy clustering, under the assumptions of General Relativity and Gaussian, adiabatic initial conditions. Key components of the bias expansion are all leading local gravitational observables, which include the matter density but also tidal fields and their time derivatives. We hence expand the definition of local bias to encompass all these contributions. This derivation is followed by a presentation of the peak-background split in its general form, which elucidates the physical meaning of the bias parameters, and a detailed description of the connection between bias parameters and galaxy statistics. We then review the excursion-set formalism and peak theory which provide predictions for the values of the bias parameters. In the remainder of the review, we consider the generalizations of galaxy bias required in the presence of various types of cosmological physics that go beyond pressureless matter with adiabatic, Gaussian initial conditions: primordial non-Gaussianity, massive neutrinos, baryon-CDM isocurvature perturbations, dark energy, and modified gravity. Finally, we discuss how the description of galaxy bias in the galaxies' rest frame is related to clustering statistics measured from the observed angular positions and redshifts in actual galaxy catalogs.

  14. The role of alginate in Azotobacter vinelandii aggregation in submerged culture

    Directory of Open Access Journals (Sweden)

    Edith Coronado

    2008-01-01

    Full Text Available The culture of strain LA21, a non-mucoid strain of Azotobacter vinelandii derivative of ATCC 9046, revealed that alginate is not necessary for aggregate formation. In fact, the non-mucoid strain LA21 developed aggregates significantly larger than those of the mucoid strain (ATCC 9046, which suggests that alginate has a detrimental effect on the aggregate size, due to its properties as a surface active agent. Treating the aggregates with a protease caused a decrease in the equivalent diameter of the structures, suggesting the participation of extracellular proteins in the aggregation. Key words: Aggregation; Azotobacter vinelandii; alginate; mutant strain; mucoid.

  15. Large-scale galaxy bias

    Science.gov (United States)

    Jeong, Donghui; Desjacques, Vincent; Schmidt, Fabian

    2018-01-01

    Here, we briefly introduce the key results of the recent review (arXiv:1611.09787), whose abstract is as following. This review presents a comprehensive overview of galaxy bias, that is, the statistical relation between the distribution of galaxies and matter. We focus on large scales where cosmic density fields are quasi-linear. On these scales, the clustering of galaxies can be described by a perturbative bias expansion, and the complicated physics of galaxy formation is absorbed by a finite set of coefficients of the expansion, called bias parameters. The review begins with a detailed derivation of this very important result, which forms the basis of the rigorous perturbative description of galaxy clustering, under the assumptions of General Relativity and Gaussian, adiabatic initial conditions. Key components of the bias expansion are all leading local gravitational observables, which include the matter density but also tidal fields and their time derivatives. We hence expand the definition of local bias to encompass all these contributions. This derivation is followed by a presentation of the peak-background split in its general form, which elucidates the physical meaning of the bias parameters, and a detailed description of the connection between bias parameters and galaxy (or halo) statistics. We then review the excursion set formalism and peak theory which provide predictions for the values of the bias parameters. In the remainder of the review, we consider the generalizations of galaxy bias required in the presence of various types of cosmological physics that go beyond pressureless matter with adiabatic, Gaussian initial conditions: primordial non-Gaussianity, massive neutrinos, baryon-CDM isocurvature perturbations, dark energy, and modified gravity. Finally, we discuss how the description of galaxy bias in the galaxies' rest frame is related to clustering statistics measured from the observed angular positions and redshifts in actual galaxy catalogs.

  16. Information environment, behavioral biases, and home bias in analysts’ recommendations

    DEFF Research Database (Denmark)

    Farooq, Omar; Taouss, Mohammed

    2012-01-01

    Can information environment of a firm explain home bias in analysts’ recommendations? Can the extent of agency problems explain optimism difference between foreign and local analysts? This paper answers these questions by documenting the effect of information environment on home bias in analysts’...

  17. A simple model for the influence of meiotic conversion tracts on GC content.

    Directory of Open Access Journals (Sweden)

    Marie-Claude Marsolier-Kergoat

    Full Text Available A strong correlation between GC content and recombination rate is observed in many eukaryotes, which is thought to be due to conversion events linked to the repair of meiotic double-strand breaks. In several organisms, the length of conversion tracts has been shown to decrease exponentially with increasing distance from the sites of meiotic double-strand breaks. I show here that this behavior leads to a simple analytical model for the evolution and the equilibrium state of the GC content of sequences devoid of meiotic double-strand break sites. In the yeast Saccharomyces cerevisiae, meiotic double-strand breaks are practically excluded from protein-coding sequences. A good fit was observed between the predictions of the model and the variations of the average GC content of the third codon position (GC3 of S. cerevisiae genes. Moreover, recombination parameters that can be extracted by fitting the data to the model coincide with experimentally determined values. These results thus indicate that meiotic recombination plays an important part in determining the fluctuations of GC content in yeast coding sequences. The model also accounted for the different patterns of GC variations observed in the genes of Candida species that exhibit a variety of sexual lifestyles, and hence a wide range of meiotic recombination rates. Finally, the variations of the average GC3 content of human and chicken coding sequences could also be fitted by the model. These results suggest the existence of a widespread pattern of GC variation in eukaryotic genes due to meiotic recombination, which would imply the generality of two features of meiotic recombination: its association with GC-biased gene conversion and the quasi-exclusion of meiotic double-strand breaks from coding sequences. Moreover, the model points out to specific constraints on protein fragments encoded by exon terminal sequences, which are the most affected by the GC bias.

  18. Optical and Electrical Performance of MOS-Structure Silicon Solar Cells with Antireflective Transparent ITO and Plasmonic Indium Nanoparticles under Applied Bias Voltage.

    Science.gov (United States)

    Ho, Wen-Jeng; Sue, Ruei-Siang; Lin, Jian-Cheng; Syu, Hong-Jang; Lin, Ching-Fuh

    2016-08-10

    This paper reports impressive improvements in the optical and electrical performance of metal-oxide-semiconductor (MOS)-structure silicon solar cells through the incorporation of plasmonic indium nanoparticles (In-NPs) and an indium-tin-oxide (ITO) electrode with periodic holes (perforations) under applied bias voltage. Samples were prepared using a plain ITO electrode or perforated ITO electrode with and without In-NPs. The samples were characterized according to optical reflectance, dark current voltage, induced capacitance voltage, external quantum efficiency, and photovoltaic current voltage. Our results indicate that induced capacitance voltage and photovoltaic current voltage both depend on bias voltage, regardless of the type of ITO electrode. Under a bias voltage of 4.0 V, MOS cells with perforated ITO and plain ITO, respectively, presented conversion efficiencies of 17.53% and 15.80%. Under a bias voltage of 4.0 V, the inclusion of In-NPs increased the efficiency of cells with perforated ITO and plain ITO to 17.80% and 16.87%, respectively.

  19. Optical and Electrical Performance of MOS-Structure Silicon Solar Cells with Antireflective Transparent ITO and Plasmonic Indium Nanoparticles under Applied Bias Voltage

    Directory of Open Access Journals (Sweden)

    Wen-Jeng Ho

    2016-08-01

    Full Text Available This paper reports impressive improvements in the optical and electrical performance of metal-oxide-semiconductor (MOS-structure silicon solar cells through the incorporation of plasmonic indium nanoparticles (In-NPs and an indium-tin-oxide (ITO electrode with periodic holes (perforations under applied bias voltage. Samples were prepared using a plain ITO electrode or perforated ITO electrode with and without In-NPs. The samples were characterized according to optical reflectance, dark current voltage, induced capacitance voltage, external quantum efficiency, and photovoltaic current voltage. Our results indicate that induced capacitance voltage and photovoltaic current voltage both depend on bias voltage, regardless of the type of ITO electrode. Under a bias voltage of 4.0 V, MOS cells with perforated ITO and plain ITO, respectively, presented conversion efficiencies of 17.53% and 15.80%. Under a bias voltage of 4.0 V, the inclusion of In-NPs increased the efficiency of cells with perforated ITO and plain ITO to 17.80% and 16.87%, respectively.

  20. Combining Energy Conversion and Storage: A Solar Powered Supercapacitor

    International Nuclear Information System (INIS)

    Narayanan, Remya; Kumar, P. Naresh; Deepa, Melepurath; Srivastava, Avanish Kumar

    2015-01-01

    Graphical abstract: - Highlights: • A plasmonic TiO_2/CdS/Au fibers photoanode is fabricated for the first time. • The efficiency of the plasmonic cell is greater by 1.35 times than the non-plasmonic one. • A solar powered supercapacitor is developed with plasmonic photoanode and multiwalled carbon nanotubes. • The solar cell current charges the supercapacitor. • A specific capacitance of 150 F g"−"1 is achieved under sunlight without any external bias. - Abstract: A solar powered supercapacitor wherein a plasmonic quantum dot solar cell (QDSC) sources the photocurrent for charging/discharging a conjoined supercapacitor based on multiwalled carbon nanotubes (MWCNTs) is demonstrated. Gold or Au fibers are integrated into a titanium dioxide/cadmium sulfide (TiO_2/CdS) electrode to yield a TiO_2/CdS/Au photoanode. The plasmonic effect of Au fibers is reflected in the higher incident photon to current conversion efficiency (IPCE = 55%) and an improved overall power conversion efficiency (3.45%) produced by the TiO_2/CdS/Au photoanode relative to the non-plasmonic TiO_2/CdS photoanode. A Janus type bi-functional electrode composed of MWCNTs on either face separated by glass is prepared and it is coupled with the TiO_2/CdS/Au electrode and another MWCNT electrode to yield the tandem solar powered supercapacitor. By channelling the photocurrent produced by the QDSC part, under 0.1 sun illumination, the capacitance of the symmetric supercapacitor, without the application of any external bias is 150 F g"−"1 which compares well with reported values of electrically powered MWCNT supercapacitors. Our innovative design for a photo-supercapacitor offers a new paradigm for combining low cost photovoltaics with energy storage to yield a technologically useful device that needs nothing else other than solar energy to run.

  1. Bond and Equity Home Bias and Foreign Bias: an International Study

    OpenAIRE

    VanPée, Rosanne; De Moor, Lieven

    2012-01-01

    In this paper we explore tentatively and formally the differences between bond and equity home bias and foreign bias based on one large scale dataset including developed and emerging markets for the period 2001 to 2010. We set the stage by tentatively and formally linking the diversion of bond and equity home bias in OECD countries to the increasing public debt issues under the form of government bonds i.e. the supply-driven argument. Unlike Fidora et al. (2007) we do not find that exchange r...

  2. Reading Comprehension in Boys with ADHD: The Mediating Roles of Working Memory and Orthographic Conversion.

    Science.gov (United States)

    Friedman, Lauren M; Rapport, Mark D; Raiker, Joseph S; Orban, Sarah A; Eckrich, Samuel J

    2017-02-01

    Reading comprehension difficulties in children with ADHD are well established; however, limited information exists concerning the cognitive mechanisms that contribute to these difficulties and the extent to which they interact with one another. The current study examines two broad cognitive processes known to be involved in children's reading comprehension abilities-(a) working memory (i.e., central executive processes [CE], phonological short-term memory [PH STM], and visuospatial short-term memory [VS STM]) and (b) orthographic conversion (i.e., conversion of visually presented text to a phonological code)-to elucidate their unique and interactive contribution to ADHD-related reading comprehension differences. Thirty-one boys with ADHD-combined type and 30 typically developing (TD) boys aged 8 to 12 years (M = 9.64, SD = 1.22) were administered multiple counterbalanced tasks assessing WM and orthographic conversion processes. Relative to TD boys, boys with ADHD exhibited significant deficits in PH STM (d = -0.70), VS STM (d = -0.92), CE (d = -1.58), and orthographic conversion (d = -0.93). Bias-corrected, bootstrapped mediation analyses revealed that CE and orthographic conversion processes modeled separately mediated ADHD-related reading comprehension differences partially, whereas PH STM and VS STM did not. CE and orthographic conversion modeled jointly mediated ADHD-related reading comprehension differences fully wherein orthographic conversion's large magnitude influence on reading comprehension occurred indirectly through CE's impact on the orthographic system. The findings suggest that adaptive cognitive interventions designed to improve reading-related outcomes in children with ADHD may benefit by including modules that train CE and orthographic conversion processes independently and interactively.

  3. Performance improvement of magnetized coaxial plasma gun by magnetic circuit on a bias coil

    Science.gov (United States)

    Edo, Takahiro; Matsumoto, Tadafumi; Asai, Tomohiko; Kamino, Yasuhiro; Inomoto, Michiaki; Gota, Hiroshi

    2016-10-01

    A magnetized coaxial plasmoid accelerator has been utilized for compact torus (CT) injection to refuel into fusion reactor core plasma. Recently, CT injection experiments have been conducted on the C-2/C-2U facility at Tri Alpha Energy. In the series of experiments successful refueling, i.e. increased particle inventory of field-reversed configuration (FRC) plasma, has been observed. In order to improve the performance of CT injector and to refuel in the upgraded FRC device, called C-2W, with higher confinement magnetic field, magnetic circuit consisting of magnetic material onto a bias magnetic coil is currently being tested at Nihon University. Numerical work suggests that the optimized bias magnetic field distribution realizes the increased injection velocity because of higher conversion efficiency of Lorenz self force to kinetic energy. Details of the magnetic circuit design as well as results of the test experiment and field calculations will be presented and discussed.

  4. Uranium conversion

    International Nuclear Information System (INIS)

    Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina

    2006-03-01

    FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF 6 and UF 4 are present require equipment that is made of corrosion resistant material

  5. Sexy gene conversions: locating gene conversions on the X-chromosome.

    Science.gov (United States)

    Lawson, Mark J; Zhang, Liqing

    2009-08-01

    Gene conversion can have a profound impact on both the short- and long-term evolution of genes and genomes. Here, we examined the gene families that are located on the X-chromosomes of human (Homo sapiens), chimpanzee (Pan troglodytes), mouse (Mus musculus) and rat (Rattus norvegicus) for evidence of gene conversion. We identified seven gene families (WD repeat protein family, Ferritin Heavy Chain family, RAS-related Protein RAB-40 family, Diphosphoinositol polyphosphate phosphohydrolase family, Transcription Elongation Factor A family, LDOC1-related family, Zinc Finger Protein ZIC, and GLI family) that show evidence of gene conversion. Through phylogenetic analyses and synteny evidence, we show that gene conversion has played an important role in the evolution of these gene families and that gene conversion has occurred independently in both primates and rodents. Comparing the results with those of two gene conversion prediction programs (GENECONV and Partimatrix), we found that both GENECONV and Partimatrix have very high false negative rates (i.e. failed to predict gene conversions), which leads to many undetected gene conversions. The combination of phylogenetic analyses with physical synteny evidence exhibits high resolution in the detection of gene conversions.

  6. NiO/Fe(001): Magnetic anisotropy, exchange bias, and interface structure

    Energy Technology Data Exchange (ETDEWEB)

    Mlynczak, E. [Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30-239 Krakow (Poland); Luches, P. [S3, Istituto Nanoscienze-CNR, Via G. Campi 213/a, I-41125 Modena (Italy); Valeri, S. [S3, Istituto Nanoscienze-CNR, Via G. Campi 213/a, I-41125 Modena (Italy); Dipartimento di Scienze Fisiche, Matematiche e Informatiche, Universita di Modena e Reggio Emilia, Via G. Campi 213/a, 41100 Modena (Italy); Korecki, J. [Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30-239 Krakow (Poland); Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, al.Mickiewicza 30, 30-059 Krakow (Poland)

    2013-06-21

    The magnetic and structural properties of NiO/Fe epitaxial bilayers grown on MgO(001) were studied using magnetooptic Kerr effect (MOKE) and conversion electron Moessbauer spectroscopy (CEMS). The bilayers were prepared under ultra high vacuum conditions using molecular beam epitaxy with oblique deposition. Two systems were compared: one showing the exchange bias (100ML-NiO/24ML-Fe), ML stands for a monolayer, and another where the exchange bias was not observed (50ML-NiO/50ML-Fe). For both, the magnetic anisotropy was found to be complex, yet dominated by the growth-induced uniaxial anisotropy. The training effect was observed for the 100ML-NiO/24ML-Fe system and quantitatively described using the spin glass model. The composition and magnetic state of the interfacial Fe layers were studied using {sup 57}Fe-CEMS. An iron oxide phase (Fe{sup 3+}{sub 4}Fe{sup 2+}{sub 1}O{sub 7}), as thick as 31 A, was identified at the NiO/Fe interface in the as-deposited samples. The ferrimagnetic nature of the interfacial iron oxide film explains the complex magnetic anisotropy observed in the samples.

  7. Decay of velvet worms (Onychophora), and bias in the fossil record of lobopodians.

    Science.gov (United States)

    Murdock, Duncan Je; Gabbott, Sarah E; Mayer, Georg; Purnell, Mark A

    2014-11-29

    among the taphonomic biases that have affected organisms where decay-resistant features of the anatomy are rich in phylogenetically informative characters. Conversely, organisms which possess decay-resistant body parts but have informative characters concentrated in decay-prone tissues will be just as liable to bias as those that lack decay-resistant body parts. Further experimental analysis of decay is required to test these hypotheses.

  8. Dietary shift and dysbiosis may trigger mucous stools in giant pandas (Ailuropoda melanoleuca

    Directory of Open Access Journals (Sweden)

    Candace L Williams

    2016-05-01

    Full Text Available Dietary shifts can result in dysbiosis between the host and its gastrointestinal tract (GIT microbiota, leading to negative outcomes including inflammation. Giant pandas (Ailuropoda melanoleuca are physiologically classified as carnivores; however, they consume a herbivorous diet with dramatic seasonal feeding shifts and episodes of chronic GIT distress with symptoms including abdominal pain, loss of appetite and the excretion of mucous stools (mucoids. These episodes adversely affect the overall nutritional and health status of giant pandas. Here, we examined the fecal microbiota of two giant pandas’ normal and mucoid stools and compared these microbiota to baseline samples from a season with historically few episodes. To identify the microbiota present, we isolated and sequenced 16S rRNA using next-generation sequencing. Mucoids occurred following a seasonal feeding switch from predominately bamboo culm (stalk to leaves. All fecal samples displayed low diversity and were dominated by bacterial in the phyla Firmicutes and to a lesser extent, the Proteobacteria. Fecal samples immediately prior to mucoid episodes had lower microbial diversity compared to baseline samples, followed by increased diversity in mucoids. Mucoids were mostly comprised of common mucosal-associated taxa including Streptococcus and Leuconostoc species, and exhibited increased abundance for bacteria in the family Pasteurellaceae. Taken together, these findings indicate that diet-induced intestinal dysbiosis in giant pandas likely results in an expulsion of the mucosal lining in the form of mucoids. We suggest that these occurrences serve to reset their GIT microbiota, as giant pandas have retained a carnivorous GIT anatomy while shifting to an herbivorous diet.

  9. Cognitive Bias in Systems Verification

    Science.gov (United States)

    Larson, Steve

    2012-01-01

    Working definition of cognitive bias: Patterns by which information is sought and interpreted that can lead to systematic errors in decisions. Cognitive bias is used in diverse fields: Economics, Politics, Intelligence, Marketing, to name a few. Attempts to ground cognitive science in physical characteristics of the cognitive apparatus exceed our knowledge. Studies based on correlations; strict cause and effect is difficult to pinpoint. Effects cited in the paper and discussed here have been replicated many times over, and appear sound. Many biases have been described, but it is still unclear whether they are all distinct. There may only be a handful of fundamental biases, which manifest in various ways. Bias can effect system verification in many ways . Overconfidence -> Questionable decisions to deploy. Availability -> Inability to conceive critical tests. Representativeness -> Overinterpretation of results. Positive Test Strategies -> Confirmation bias. Debiasing at individual level very difficult. The potential effect of bias on the verification process can be managed, but not eliminated. Worth considering at key points in the process.

  10. Biases in categorization

    NARCIS (Netherlands)

    Das-Smaal, E.A.

    1990-01-01

    On what grounds can we conclude that an act of categorization is biased? In this chapter, it is contended that in the absence of objective norms of what categories actually are, biases in categorization can only be specified in relation to theoretical understandings of categorization. Therefore, the

  11. The Role of Conversation Policy in Carrying Out Agent Conversations

    International Nuclear Information System (INIS)

    Link, Hamilton E.; Phillips, Laurence R.

    1999-01-01

    Structured conversation diagrams, or conversation specifications, allow agents to have predictable interactions and achieve predefined information-based goals, but they lack the flexibility needed to function robustly in an unpredictable environment. We propose a mechanism that combines a typical conversation structure with a separately established policy to generate an actual conversation. The word ''policy'' connotes a high-level direction external to a specific planned interaction with the environment. Policies, which describe acceptable procedures and influence decisions, can be applied to broad sets of activity. Based on their observation of issues related to a policy, agents may dynamically adjust their communication patterns. The policy object describes limitations, constraints, and requirements that may affect the conversation in certain circumstances. Using this new mechanism of interaction simplifies the description of individual conversations and allows domain-specific issues to be brought to bear more easily during agent communication. By following the behavior of the conversation specification when possible and deferring to the policy to derive behavior in exceptional circumstances, an agent is able to function predictably under normal situations and still act rationally in abnormal situations. Different conversation policies applied to a given conversation specification can change the nature of the interaction without changing the specification

  12. Cognitive bias measurement and social anxiety disorder: Correlating self-report data and attentional bias

    Directory of Open Access Journals (Sweden)

    Alexander Miloff

    2015-09-01

    Full Text Available Social anxiety disorder (SAD and attentional bias are theoretically connected in cognitive behavioral therapeutic models. In fact, there is an emerging field focusing on modifying attentional bias as a stand-alone treatment. However, it is unclear to what degree these attentional biases are present before commencing treatment. The purpose of this study was to measure pre-treatment attentional bias in 153 participants diagnosed with SAD using a home-based Internet version of the dot-probe paradigm. Results showed no significant correlation for attentional bias (towards or away from negative words or faces and the self-rated version of the Liebowitz Social Anxiety Scale (LSAS-SR. However, two positive correlations were found for the secondary measures Generalized Anxiety Disorder 7 (GAD-7 and Patient Health Questionnaire 9 (PHQ-9. These indicated that those with elevated levels of anxiety and depression had a higher bias towards negative faces in neutral–negative and positive–negative valence combinations, respectively. The unreliability of the dot-probe paradigm and home-based Internet delivery are discussed to explain the lack of correlations between LSAS-SR and attentional bias. Changes to the dot-probe task are suggested that could improve reliability.

  13. Threat bias, not negativity bias, underpins differences in political ideology.

    Science.gov (United States)

    Lilienfeld, Scott O; Latzman, Robert D

    2014-06-01

    Although disparities in political ideology are rooted partly in dispositional differences, Hibbing et al.'s analysis paints with an overly broad brush. Research on the personality correlates of liberal-conservative differences points not to global differences in negativity bias, but to differences in threat bias, probably emanating from differences in fearfulness. This distinction bears implications for etiological research and persuasion efforts.

  14. Good practices for quantitative bias analysis.

    Science.gov (United States)

    Lash, Timothy L; Fox, Matthew P; MacLehose, Richard F; Maldonado, George; McCandless, Lawrence C; Greenland, Sander

    2014-12-01

    Quantitative bias analysis serves several objectives in epidemiological research. First, it provides a quantitative estimate of the direction, magnitude and uncertainty arising from systematic errors. Second, the acts of identifying sources of systematic error, writing down models to quantify them, assigning values to the bias parameters and interpreting the results combat the human tendency towards overconfidence in research results, syntheses and critiques and the inferences that rest upon them. Finally, by suggesting aspects that dominate uncertainty in a particular research result or topic area, bias analysis can guide efficient allocation of sparse research resources. The fundamental methods of bias analyses have been known for decades, and there have been calls for more widespread use for nearly as long. There was a time when some believed that bias analyses were rarely undertaken because the methods were not widely known and because automated computing tools were not readily available to implement the methods. These shortcomings have been largely resolved. We must, therefore, contemplate other barriers to implementation. One possibility is that practitioners avoid the analyses because they lack confidence in the practice of bias analysis. The purpose of this paper is therefore to describe what we view as good practices for applying quantitative bias analysis to epidemiological data, directed towards those familiar with the methods. We focus on answering questions often posed to those of us who advocate incorporation of bias analysis methods into teaching and research. These include the following. When is bias analysis practical and productive? How does one select the biases that ought to be addressed? How does one select a method to model biases? How does one assign values to the parameters of a bias model? How does one present and interpret a bias analysis?. We hope that our guide to good practices for conducting and presenting bias analyses will encourage

  15. Hindsight bias and outcome bias in the social construction of medical negligence: a review.

    Science.gov (United States)

    Hugh, Thomas B; Dekker, Sidney W A

    2009-05-01

    Medical negligence has been the subject of much public debate in recent decades. Although the steep increase in the frequency and size of claims against doctors at the end of the last century appears to have plateaued, in Australia at least, medical indemnity costs and consequences are still a matter of concern for doctors, medical defence organisations and governments in most developed countries. Imprecision in the legal definition of negligence opens the possibility that judgments of this issue at several levels may be subject to hindsight and outcome bias. Hindsight bias relates to the probability of an adverse event perceived by a retrospective observer ("I would have known it was going to happen"), while outcome bias is a largely subconscious cognitive distortion produced by the observer's knowledge of the adverse outcome. This review examines the relevant legal, medical, psychological and sociological literature on the operation of these pervasive and universal biases in the retrospective evaluation of adverse events. A finding of medical negligence is essentially an after-the-event social construction and is invariably affected by hindsight bias and knowledge of the adverse outcome. Such biases obviously pose a threat to the fairness of judgments. A number of debiasing strategies have been suggested but are relatively ineffective because of the universality and strength of these biases and the inherent difficulty of concealing from expert witnesses knowledge of the outcome. Education about the effect of the biases is therefore important for lawyers, medical expert witnesses and the judiciary.

  16. Photovoltaic Bias Generator

    Science.gov (United States)

    2018-02-01

    Department of the Army position unless so designated by other authorized documents. Citation of manufacturer’s or trade names does not constitute an... Interior view of the photovoltaic bias generator showing wrapped-wire side of circuit board...3 Fig. 4 Interior view of the photovoltaic bias generator showing component side of circuit board

  17. Bias-correction in vector autoregressive models

    DEFF Research Database (Denmark)

    Engsted, Tom; Pedersen, Thomas Quistgaard

    2014-01-01

    We analyze the properties of various methods for bias-correcting parameter estimates in both stationary and non-stationary vector autoregressive models. First, we show that two analytical bias formulas from the existing literature are in fact identical. Next, based on a detailed simulation study......, we show that when the model is stationary this simple bias formula compares very favorably to bootstrap bias-correction, both in terms of bias and mean squared error. In non-stationary models, the analytical bias formula performs noticeably worse than bootstrapping. Both methods yield a notable...... improvement over ordinary least squares. We pay special attention to the risk of pushing an otherwise stationary model into the non-stationary region of the parameter space when correcting for bias. Finally, we consider a recently proposed reduced-bias weighted least squares estimator, and we find...

  18. Bias versus bias: harnessing hindsight to reveal paranormal belief change beyond demand characteristics.

    Science.gov (United States)

    Kane, Michael J; Core, Tammy J; Hunt, R Reed

    2010-04-01

    Psychological change is difficult to assess, in part because self-reported beliefs and attitudes may be biased or distorted. The present study probed belief change, in an educational context, by using the hindsight bias to counter another bias that generally plagues assessment of subjective change. Although research has indicated that skepticism courses reduce paranormal beliefs, those findings may reflect demand characteristics (biases toward desired, skeptical responses). Our hindsight-bias procedure circumvented demand by asking students, following semester-long skepticism (and control) courses, to recall their precourse levels of paranormal belief. People typically remember themselves as previously thinking, believing, and acting as they do now, so current skepticism should provoke false recollections of previous skepticism. Given true belief change, therefore, skepticism students should have remembered themselves as having been more skeptical than they were. They did, at least about paranormal topics that were covered most extensively in the course. Our findings thus show hindsight to be useful in evaluating cognitive change beyond demand characteristics.

  19. Improvement of skeleton conversion in ICRP reference phantom conversion project

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhao Jun; Yeom, Yeon Soo; Thang, Nguyen Tat; Kim, Han Sung; Han, Min Cheol; Kim, Chan Hyeong [Dept. of Nuclear Engineering, Hanyang University, Seoul (Korea, Republic of); Kim, Seong Hoon [Dept. of Radiation Oncology, College of Medicine, Hanyang University, Seoul (Korea, Republic of)

    2014-11-15

    In the previous skeleton conversion, most bones were directly converted from the ICRP voxel phantoms by using the 3D rendering method whereas several complex-shape bones (cranium, ribs, spines, feet, and hands) were not able to be directly converted. We alternatively employed the corresponding well-defined polygonal models and attempted to adjust them to match the voxel models. However, this approach was unsatisfactory. The shapes of the alternative models were significantly different from those of the voxel models, making it virtually impossible to exactly match the voxel models as shown in Fig. 3 (left). In order to overcome the difficulty in the complex bone conversion, the present study developed a new conversion method and converted these complex bones voxel models of the ICRP male phantom to polygonal models. The present study developed the new conversion method and successfully improved polygonal models for cranium, ribs, and spines for the ICRP male phantom. The new conversion method will be also applied to the complex bone conversion for the ICRP female phantom as well as other complex organ conversion in the future.

  20. Improvement of skeleton conversion in ICRP reference phantom conversion project

    International Nuclear Information System (INIS)

    Wang, Zhao Jun; Yeom, Yeon Soo; Thang, Nguyen Tat; Kim, Han Sung; Han, Min Cheol; Kim, Chan Hyeong; Kim, Seong Hoon

    2014-01-01

    In the previous skeleton conversion, most bones were directly converted from the ICRP voxel phantoms by using the 3D rendering method whereas several complex-shape bones (cranium, ribs, spines, feet, and hands) were not able to be directly converted. We alternatively employed the corresponding well-defined polygonal models and attempted to adjust them to match the voxel models. However, this approach was unsatisfactory. The shapes of the alternative models were significantly different from those of the voxel models, making it virtually impossible to exactly match the voxel models as shown in Fig. 3 (left). In order to overcome the difficulty in the complex bone conversion, the present study developed a new conversion method and converted these complex bones voxel models of the ICRP male phantom to polygonal models. The present study developed the new conversion method and successfully improved polygonal models for cranium, ribs, and spines for the ICRP male phantom. The new conversion method will be also applied to the complex bone conversion for the ICRP female phantom as well as other complex organ conversion in the future

  1. Toward a synthesis of cognitive biases: how noisy information processing can bias human decision making.

    Science.gov (United States)

    Hilbert, Martin

    2012-03-01

    A single coherent framework is proposed to synthesize long-standing research on 8 seemingly unrelated cognitive decision-making biases. During the past 6 decades, hundreds of empirical studies have resulted in a variety of rules of thumb that specify how humans systematically deviate from what is normatively expected from their decisions. Several complementary generative mechanisms have been proposed to explain those cognitive biases. Here it is suggested that (at least) 8 of these empirically detected decision-making biases can be produced by simply assuming noisy deviations in the memory-based information processes that convert objective evidence (observations) into subjective estimates (decisions). An integrative framework is presented to show how similar noise-based mechanisms can lead to conservatism, the Bayesian likelihood bias, illusory correlations, biased self-other placement, subadditivity, exaggerated expectation, the confidence bias, and the hard-easy effect. Analytical tools from information theory are used to explore the nature and limitations that characterize such information processes for binary and multiary decision-making exercises. The ensuing synthesis offers formal mathematical definitions of the biases and their underlying generative mechanism, which permits a consolidated analysis of how they are related. This synthesis contributes to the larger goal of creating a coherent picture that explains the relations among the myriad of seemingly unrelated biases and their potential psychological generative mechanisms. Limitations and research questions are discussed.

  2. P. aeruginosa in the paranasal sinuses and transplanted lungs have similar adaptive mutations as isolates from chronically infected CF lungs

    DEFF Research Database (Denmark)

    Ciofu, Oana; Johansen, Helle Krogh; Aanaes, Kasper

    2013-01-01

    BACKGROUND: Pseudomonas aeruginosa cells are present as biofilms in the paranasal sinuses and the lungs of chronically infected cystic fibrosis (CF) patients. Since different inflammatory responses and selective antibiotic pressures are acting in the sinuses compared with the lungs, we compared...... the adaptive profiles of mucoid and non-mucoid isolates from the two locations. METHODS: We studied the genetic basis of phenotypic diversification and gene expression profiles in sequential lung and sinus P. aeruginosa isolates from four chronically infected CF patients, including pre- and post-lung...... transplantation isolates. RESULTS: The same phenotypes caused by similar mutations and similar gene expression profiles were found in mucoid and non-mucoid isolates from the paranasal sinuses and from the lungs before and after transplantation. CONCLUSION: Bilateral exchange of P. aeruginosa isolates between...

  3. Discourse analysis: Conversational analysis of the internal conversation in Oracle Corporation Malaysia

    Directory of Open Access Journals (Sweden)

    Marwa Marwa

    2017-07-01

    Full Text Available This study highlights the internal conversation which takes place in Oracle CorporationMalaysia. Through the study, it will be shown how conversational analysis is used toanalyze the transcription of a telephone conversation between Oracle staffs. The analysisof the transcriptions will apply a few basic concepts of conversational analysis; turntakingorganization, and the adjacency pair. The objective of the study is to find out howthe internal conversations takes place by focusing on the conversation itself, that is, theconversational structures spontaneously produced by people during talk ranging fromturn-taking strategies, how topics are introduced, conversation closings and so on. Bylooking in detail at such talk, we can gain a detailed understanding of how the staffs seethemselves in relation to the company that influence their daily lives.Keywords: conversational analysis, turn-taking, adjacency pairs

  4. Mood-congruent attention and memory bias in dysphoria: Exploring the coherence among information-processing biases.

    Science.gov (United States)

    Koster, Ernst H W; De Raedt, Rudi; Leyman, Lemke; De Lissnyder, Evi

    2010-03-01

    Recent studies indicate that depression is characterized by mood-congruent attention bias at later stages of information-processing. Moreover, depression has been associated with enhanced recall of negative information. The present study tested the coherence between attention and memory bias in dysphoria. Stable dysphoric (n = 41) and non-dysphoric (n = 41) undergraduates first performed a spatial cueing task that included negative, positive, and neutral words. Words were presented for 250 ms under conditions that allowed or prevented elaborate processing. Memory for the words presented in the cueing task was tested using incidental free recall. Dysphoric individuals exhibited an attention bias for negative words in the condition that allowed elaborate processing, with the attention bias for negative words predicting free recall of negative words. Results demonstrate the coherence of attention and memory bias in dysphoric individuals and provide suggestions on the influence of attention bias on further processing of negative material. 2009 Elsevier Ltd. All rights reserved.

  5. Supported black phosphorus nanosheets as hydrogen-evolving photocatalyst achieving 5.4% energy conversion efficiency at 353 K.

    Science.gov (United States)

    Tian, Bin; Tian, Bining; Smith, Bethany; Scott, M C; Hua, Ruinian; Lei, Qin; Tian, Yue

    2018-04-11

    Solar-driven water splitting using powdered catalysts is considered as the most economical means for hydrogen generation. However, four-electron-driven oxidation half-reaction showing slow kinetics, accompanying with insufficient light absorption and rapid carrier combination in photocatalysts leads to low solar-to-hydrogen energy conversion efficiency. Here, we report amorphous cobalt phosphide (Co-P)-supported black phosphorus nanosheets employed as photocatalysts can simultaneously address these issues. The nanosheets exhibit robust hydrogen evolution from pure water (pH = 6.8) without bias and hole scavengers, achieving an apparent quantum efficiency of 42.55% at 430 nm and energy conversion efficiency of over 5.4% at 353 K. This photocatalytic activity is attributed to extremely efficient utilization of solar energy (~75% of solar energy) by black phosphorus nanosheets and high-carrier separation efficiency by amorphous Co-P. The hybrid material design realizes efficient solar-to-chemical energy conversion in suspension, demonstrating the potential of black phosphorus-based materials as catalysts for solar hydrogen production.

  6. Bias in clinical intervention research

    DEFF Research Database (Denmark)

    Gluud, Lise Lotte

    2006-01-01

    Research on bias in clinical trials may help identify some of the reasons why investigators sometimes reach the wrong conclusions about intervention effects. Several quality components for the assessment of bias control have been suggested, but although they seem intrinsically valid, empirical...... evidence is needed to evaluate their effects on the extent and direction of bias. This narrative review summarizes the findings of methodological studies on the influence of bias in clinical trials. A number of methodological studies suggest that lack of adequate randomization in published trial reports...

  7. Stimulus-Driven Attention, Threat Bias, and Sad Bias in Youth with a History of an Anxiety Disorder or Depression.

    Science.gov (United States)

    Sylvester, Chad M; Hudziak, James J; Gaffrey, Michael S; Barch, Deanna M; Luby, Joan L

    2016-02-01

    Attention biases towards threatening and sad stimuli are associated with pediatric anxiety and depression, respectively. The basic cognitive mechanisms associated with attention biases in youth, however, remain unclear. Here, we tested the hypothesis that threat bias (selective attention for threatening versus neutral stimuli) but not sad bias relies on stimulus-driven attention. We collected measures of stimulus-driven attention, threat bias, sad bias, and current clinical symptoms in youth with a history of an anxiety disorder and/or depression (ANX/DEP; n = 40) as well as healthy controls (HC; n = 33). Stimulus-driven attention was measured with a non-emotional spatial orienting task, while threat bias and sad bias were measured at a short time interval (150 ms) with a spatial orienting task using emotional faces and at a longer time interval (500 ms) using a dot-probe task. In ANX/DEP but not HC, early attention bias towards threat was negatively correlated with later attention bias to threat, suggesting that early threat vigilance was associated with later threat avoidance. Across all subjects, stimulus-driven orienting was not correlated with early threat bias but was negatively correlated with later threat bias, indicating that rapid stimulus-driven orienting is linked to later threat avoidance. No parallel relationships were detected for sad bias. Current symptoms of depression but not anxiety were related to decreased stimulus-driven attention. Together, these results are consistent with the hypothesis that threat bias but not sad bias relies on stimulus-driven attention. These results inform the design of attention bias modification programs that aim to reverse threat biases and reduce symptoms associated with pediatric anxiety and depression.

  8. Stimulus-driven attention, threat bias, and sad bias in youth with a history of an anxiety disorder or depression

    Science.gov (United States)

    Sylvester, Chad M.; Hudziak, James J.; Gaffrey, Michael S.; Barch, Deanna M.; Luby, Joan L.

    2015-01-01

    Attention biases towards threatening and sad stimuli are associated with pediatric anxiety and depression, respectively. The basic cognitive mechanisms associated with attention biases in youth, however, remain unclear. Here, we tested the hypothesis that threat bias (selective attention for threatening versus neutral stimuli) but not sad bias relies on stimulus-driven attention. We collected measures of stimulus-driven attention, threat bias, sad bias, and current clinical symptoms in youth with a history of an anxiety disorder and/or depression (ANX/DEP; n=40) as well as healthy controls (HC; n=33). Stimulus-driven attention was measured with a non-emotional spatial orienting task, while threat bias and sad bias were measured at a short time interval (150 ms) with a spatial orienting task using emotional faces and at a longer time interval (500 ms) using a dot-probe task. In ANX/DEP but not HC, early attention bias towards threat was negatively correlated with later attention bias to threat, suggesting that early threat vigilance was associated with later threat avoidance. Across all subjects, stimulus-driven orienting was not correlated with early threat bias but was negatively correlated with later threat bias, indicating that rapid stimulus-driven orienting is linked to later threat avoidance. No parallel relationships were detected for sad bias. Current symptoms of depression but not anxiety were related to decreased stimulus-driven attention. Together, these results are consistent with the hypothesis that threat bias but not sad bias relies on stimulus-driven attention. These results inform the design of attention bias modification programs that aim to reverse threat biases and reduce symptoms associated with pediatric anxiety and depression. PMID:25702927

  9. Dynamically biased statistical model for the ortho/para conversion in the H2+H3+ --> H3++ H2 reaction

    Science.gov (United States)

    Gómez-Carrasco, Susana; González-Sánchez, Lola; Aguado, Alfredo; Sanz-Sanz, Cristina; Zanchet, Alexandre; Roncero, Octavio

    2012-09-01

    In this work we present a dynamically biased statistical model to describe the evolution of the title reaction from statistical to a more direct mechanism, using quasi-classical trajectories (QCT). The method is based on the one previously proposed by Park and Light [J. Chem. Phys. 126, 044305 (2007), 10.1063/1.2430711]. A recent global potential energy surface is used here to calculate the capture probabilities, instead of the long-range ion-induced dipole interactions. The dynamical constraints are introduced by considering a scrambling matrix which depends on energy and determine the probability of the identity/hop/exchange mechanisms. These probabilities are calculated using QCT. It is found that the high zero-point energy of the fragments is transferred to the rest of the degrees of freedom, what shortens the lifetime of H_5^+ complexes and, as a consequence, the exchange mechanism is produced with lower proportion. The zero-point energy (ZPE) is not properly described in quasi-classical trajectory calculations and an approximation is done in which the initial ZPE of the reactants is reduced in QCT calculations to obtain a new ZPE-biased scrambling matrix. This reduction of the ZPE is explained by the need of correcting the pure classical level number of the H_5^+ complex, as done in classical simulations of unimolecular processes and to get equivalent quantum and classical rate constants using Rice-Ramsperger-Kassel-Marcus theory. This matrix allows to obtain a ratio of hop/exchange mechanisms, α(T), in rather good agreement with recent experimental results by Crabtree et al. [J. Chem. Phys. 134, 194311 (2011), 10.1063/1.3587246] at room temperature. At lower temperatures, however, the present simulations predict too high ratios because the biased scrambling matrix is not statistical enough. This demonstrates the importance of applying quantum methods to simulate this reaction at the low temperatures of astrophysical interest.

  10. When a face type is perceived as threatening: Using general recognition theory to understand biased categorization of Afrocentric faces.

    Science.gov (United States)

    Kleider-Offutt, Heather M; Bond, Alesha D; Williams, Sarah E; Bohil, Corey J

    2018-03-07

    Prior research indicates that stereotypical Black faces (e.g., wide nose, full lips: Afrocentric) are often associated with crime and violence. The current study investigated whether stereotypical faces may bias the interpretation of facial expression to seem threatening. Stimuli were prerated by face type (stereotypical, nonstereotypical) and expression (neutral, threatening). Later in a forced-choice task, different participants categorized face stimuli as stereotypical or not and threatening or not. Regardless of prerated expression, stereotypical faces were judged as more threatening than were nonstereotypical faces. These findings were supported using computational models based on general recognition theory (GRT), indicating that decision boundaries were more biased toward the threatening response for stereotypical faces than for nonstereotypical faces. GRT analysis also indicated that perception of face stereotypicality and emotional expression are dependent, both across categories and within individual categories. Higher perceived stereotypicality predicts higher perception of threat, and, conversely, higher ratings of threat predict higher perception of stereotypicality. Implications for racial face-type bias influencing perception and decision-making in a variety of social and professional contexts are discussed.

  11. Benefits of being biased!

    Indian Academy of Sciences (India)

    Administrator

    Journal of Genetics, Vol. 83, No. 2, August 2004. Keywords. codon bias; alcohol dehydrogenase; Darwinian ... RESEARCH COMMENTARY. Benefits of being biased! SUTIRTH DEY*. Evolutionary Biology Laboratory, Evolutionary & Organismal Biology Unit,. Jawaharlal Nehru Centre for Advanced Scientific Research,.

  12. Biases in GNSS-Data Processing

    Science.gov (United States)

    Schaer, S. C.; Dach, R.; Lutz, S.; Meindl, M.; Beutler, G.

    2010-12-01

    Within the Global Positioning System (GPS) traditionally different types of pseudo-range measurements (P-code, C/A-code) are available on the first frequency that are tracked by the receivers with different technologies. For that reason, P1-C1 and P1-P2 Differential Code Biases (DCB) need to be considered in a GPS data processing with a mix of different receiver types. Since the Block IIR-M series of GPS satellites also provide C/A-code on the second frequency, P2-C2 DCB need to be added to the list of biases for maintenance. Potential quarter-cycle biases between different phase observables (specifically L2P and L2C) are another issue. When combining GNSS (currently GPS and GLONASS), careful consideration of inter-system biases (ISB) is indispensable, in particular when an adequate combination of individual GLONASS clock correction results from different sources (using, e.g., different software packages) is intended. Facing the GPS and GLONASS modernization programs and the upcoming GNSS, like the European Galileo and the Chinese Compass, an increasing number of types of biases is expected. The Center for Orbit Determination in Europe (CODE) is monitoring these GPS and GLONASS related biases for a long time based on RINEX files of the tracking network of the International GNSS Service (IGS) and in the frame of the data processing as one of the global analysis centers of the IGS. Within the presentation we give an overview on the stability of the biases based on the monitoring. Biases derived from different sources are compared. Finally, we give an outlook on the potential handling of such biases with the big variety of signals and systems expected in the future.

  13. Bias aware Kalman filters

    DEFF Research Database (Denmark)

    Drecourt, J.-P.; Madsen, H.; Rosbjerg, Dan

    2006-01-01

    This paper reviews two different approaches that have been proposed to tackle the problems of model bias with the Kalman filter: the use of a colored noise model and the implementation of a separate bias filter. Both filters are implemented with and without feedback of the bias into the model state....... The colored noise filter formulation is extended to correct both time correlated and uncorrelated model error components. A more stable version of the separate filter without feedback is presented. The filters are implemented in an ensemble framework using Latin hypercube sampling. The techniques...... are illustrated on a simple one-dimensional groundwater problem. The results show that the presented filters outperform the standard Kalman filter and that the implementations with bias feedback work in more general conditions than the implementations without feedback. 2005 Elsevier Ltd. All rights reserved....

  14. Opto-electronic conversion logic behaviour through dynamic modulation of electron/energy transfer states at the TiO2-carbon quantum dot interface.

    Science.gov (United States)

    Wang, Fang; Zhang, Yonglai; Liu, Yang; Wang, Xuefeng; Shen, Mingrong; Lee, Shuit-Tong; Kang, Zhenhui

    2013-03-07

    Here we show a bias-mediated electron/energy transfer process at the CQDs-TiO(2) interface for the dynamic modulation of opto-electronic properties. Different energy and electron transfer states have been observed in the CQDs-TNTs system due to the up-conversion photoluminescence and the electron donation/acceptance properties of the CQDs decorated on TNTs.

  15. Polymorphonuclear leucocytes consume oxygen in sputum from chronic Pseudomonas aeruginosa pneumonia in cystic fibrosis

    DEFF Research Database (Denmark)

    Kolpen, Mette; Hansen, C. R.; Bjarnsholt, Thomas

    2010-01-01

    BACKGROUND: Chronic lung infection with Pseudomonas aeruginosa is the most severe complication for patients with cystic fibrosis (CF). This infection is characterised by endobronchial mucoid biofilms surrounded by numerous polymorphonuclear leucocytes (PMNs). The mucoid phenotype offers protection...

  16. Measuring Agricultural Bias

    DEFF Research Database (Denmark)

    Jensen, Henning Tarp; Robinson, Sherman; Tarp, Finn

    The measurement issue is the key issue in the literature on trade policy-induced agri-cultural price incentive bias. This paper introduces a general equilibrium effective rate of protection (GE-ERP) measure, which extends and generalizes earlier partial equilibrium nominal protection measures...... shares and intersectoral linkages - are crucial for determining the sign and magnitude of trade policy bias. The GE-ERP measure is therefore uniquely suited to capture the full impact of trade policies on agricultural price incentives. A Monte Carlo procedure confirms that the results are robust....... For the 15 sample countries, the results indicate that the agricultural price incentive bias, which was generally perceived to exist during the 1980s, was largely eliminated during the 1990s. The results also demonstrate that general equilibrium effects and country-specific characteristics - including trade...

  17. Administrative bias in South Africa

    Directory of Open Access Journals (Sweden)

    E S Nwauche

    2005-01-01

    Full Text Available This article reviews the interpretation of section 6(2(aii of the Promotion of Administrative Justice Act which makes an administrator “biased or reasonably suspected of bias” a ground of judicial review. In this regard, the paper reviews the determination of administrative bias in South Africa especially highlighting the concept of institutional bias. The paper notes that inspite of the formulation of the bias ground of review the test for administrative bias is the reasonable apprehension test laid down in the case of President of South Africa v South African Rugby Football Union(2 which on close examination is not the same thing. Accordingly the paper urges an alternative interpretation that is based on the reasonable suspicion test enunciated in BTR Industries South Africa (Pty Ltd v Metal and Allied Workers Union and R v Roberts. Within this context, the paper constructs a model for interpreting the bias ground of review that combines the reasonable suspicion test as interpreted in BTR Industries and R v Roberts, the possibility of the waiver of administrative bias, the curative mechanism of administrative appeal as well as some level of judicial review exemplified by the jurisprudence of article 6(1 of the European Convention of Human Rights, especially in the light of the contemplation of the South African Magistrate Court as a jurisdictional route of judicial review.

  18. Attention, interpretation, and memory biases in subclinical depression: a proof-of-principle test of the combined cognitive biases hypothesis.

    Science.gov (United States)

    Everaert, Jonas; Duyck, Wouter; Koster, Ernst H W

    2014-04-01

    Emotional biases in attention, interpretation, and memory are viewed as important cognitive processes underlying symptoms of depression. To date, there is a limited understanding of the interplay among these processing biases. This study tested the dependence of memory on depression-related biases in attention and interpretation. Subclinically depressed and nondepressed participants completed a computerized version of the scrambled sentences test (measuring interpretation bias) while their eye movements were recorded (measuring attention bias). This task was followed by an incidental free recall test of previously constructed interpretations (measuring memory bias). Path analysis revealed a good fit for the model in which selective orienting of attention was associated with interpretation bias, which in turn was associated with a congruent bias in memory. Also, a good fit was observed for a path model in which biases in the maintenance of attention and interpretation were associated with memory bias. Both path models attained a superior fit compared with path models without the theorized functional relations among processing biases. These findings enhance understanding of how mechanisms of attention and interpretation regulate what is remembered. As such, they offer support for the combined cognitive biases hypothesis or the notion that emotionally biased cognitive processes are not isolated mechanisms but instead influence each other. Implications for theoretical models and emotion regulation across the spectrum of depressive symptoms are discussed.

  19. Preferences, country bias, and international trade

    NARCIS (Netherlands)

    S. Roy (Santanu); J.M.A. Viaene (Jean-Marie)

    1998-01-01

    textabstractAnalyzes international trade where consumer preferences exhibit country bias. Why country biases arise; How trade can occur in the presence of country bias; Implication for the pattern of trade and specialization.

  20. Biases in casino betting

    Directory of Open Access Journals (Sweden)

    James Sundali

    2006-07-01

    Full Text Available We examine two departures of individual perceptions of randomness from probability theory: the hot hand and the gambler's fallacy, and their respective opposites. This paper's first contribution is to use data from the field (individuals playing roulette in a casino to demonstrate the existence and impact of these biases that have been previously documented in the lab. Decisions in the field are consistent with biased beliefs, although we observe significant individual heterogeneity in the population. A second contribution is to separately identify these biases within a given individual, then to examine their within-person correlation. We find a positive and significant correlation across individuals between hot hand and gambler's fallacy biases, suggesting a common (root cause of the two related errors. We speculate as to the source of this correlation (locus of control, and suggest future research which could test this speculation.

  1. An inclusive taxonomy of behavioral biases

    Directory of Open Access Journals (Sweden)

    David Peón

    2017-07-01

    Full Text Available This paper overviews the theoretical and empirical research on behavioral biases and their influence in the literature. To provide a systematic exposition, we present a unified framework that takes the reader through an original taxonomy, based on the reviews of relevant authors in the field. In particular, we establish three broad categories that may be distinguished: heuristics and biases; choices, values and frames; and social factors. We then describe the main biases within each category, and revise the main theoretical and empirical developments, linking each bias with other biases and anomalies that are related to them, according to the literature.

  2. Uranium conversion; Urankonvertering

    Energy Technology Data Exchange (ETDEWEB)

    Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina [Swedish Defence Research Agency (FOI), Stockholm (Sweden)

    2006-03-15

    FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF{sub 6} and UF{sub 4} are present require equipment that is made of corrosion resistant material.

  3. Probing Biased Signaling in Chemokine Receptors

    DEFF Research Database (Denmark)

    Amarandi, Roxana Maria; Hjortø, Gertrud Malene; Rosenkilde, Mette Marie

    2016-01-01

    The chemokine system mediates leukocyte migration during homeostatic and inflammatory processes. Traditionally, it is described as redundant and promiscuous, with a single chemokine ligand binding to different receptors and a single receptor having several ligands. Signaling of chemokine receptors...... of others has been termed signaling bias and can accordingly be grouped into ligand bias, receptor bias, and tissue bias. Bias has so far been broadly overlooked in the process of drug development. The low number of currently approved drugs targeting the chemokine system, as well as the broad range...... of failed clinical trials, reflects the need for a better understanding of the chemokine system. Thus, understanding the character, direction, and consequence of biased signaling in the chemokine system may aid the development of new therapeutics. This review describes experiments to assess G protein...

  4. Bias-field equalizer for bubble memories

    Science.gov (United States)

    Keefe, G. E.

    1977-01-01

    Magnetoresistive Perm-alloy sensor monitors bias field required to maintain bubble memory. Sensor provides error signal that, in turn, corrects magnitude of bias field. Error signal from sensor can be used to control magnitude of bias field in either auxiliary set of bias-field coils around permanent magnet field, or current in small coils used to remagnetize permanent magnet by infrequent, short, high-current pulse or short sequence of pulses.

  5. Converse piezoelectric strain in undoped and Fe-doped AlGaN/GaN heterostructure field effect transistors studied by Raman scattering

    International Nuclear Information System (INIS)

    Sarua, A; Ji, Hangfeng; Pomeroy, J W; Kuball, M; Uren, M J; Martin, T

    2010-01-01

    Converse piezoelectric strain in undoped and Fe-doped AlGaN/GaN heterostructure field effect transistors (HFETs), i.e. the strain induced by applying bias to a transistor, was studied using micro-Raman scattering spectroscopy as a function of applied source–drain voltage for different GaN buffer doping levels and substrate types. By monitoring the phonon frequency shifts and line width of the E 2 and A 1 (LO) phonon modes of GaN, a considerable piezoelectric strain/stress was found in undoped devices, which exhibited a saturation above 40 V bias. This saturation voltage was used to quantify the deep acceptor concentration in the GaN buffer layer. Using experimental Raman data and numerical modelling of the electric field distribution in the device, it was furthermore established that Fe doping causes confinement of the strain/stress to the vicinity of the AlGaN/GaN interface, i.e. near the electron channel, with potential implications for device reliability. It was concluded that varying the structure and doping in the buffer layer has the potential to modify the converse piezoelectric strain and hence affect reliability issues in AlGaN/GaN HFETs

  6. Introduction to Unconscious Bias

    Science.gov (United States)

    Schmelz, Joan T.

    2010-05-01

    We all have biases, and we are (for the most part) unaware of them. In general, men and women BOTH unconsciously devalue the contributions of women. This can have a detrimental effect on grant proposals, job applications, and performance reviews. Sociology is way ahead of astronomy in these studies. When evaluating identical application packages, male and female University psychology professors preferred 2:1 to hire "Brian” over "Karen” as an assistant professor. When evaluating a more experienced record (at the point of promotion to tenure), reservations were expressed four times more often when the name was female. This unconscious bias has a repeated negative effect on Karen's career. This talk will introduce the concept of unconscious bias and also give recommendations on how to address it using an example for a faculty search committee. The process of eliminating unconscious bias begins with awareness, then moves to policy and practice, and ends with accountability.

  7. Research bias in judgement bias studies : a systematic review of valuation judgement literature

    NARCIS (Netherlands)

    Vincent Gruis; Pim Klamer; Cok Bakker

    2017-01-01

    Valuation judgement bias has been a research topic for several years due to its proclaimed effect on valuation accuracy. However, little is known on the emphasis of literature on judgement bias, with regard to, for instance, research methodologies, research context and robustness of research

  8. Research bias in judgement bias studies : A systematic review of valuation judgement literature

    NARCIS (Netherlands)

    Klamer, Pim; Bakker, C.; Gruis, Vincent

    2017-01-01

    Valuation judgement bias has been a research topic for several years due to its proclaimed effect on valuation accuracy. However, little is known on the emphasis of literature on judgement bias, with regard to, for instance, research methodologies, research context and robustness of research

  9. Attention bias modification training under working memory load increases the magnitude of change in attentional bias.

    Science.gov (United States)

    Clarke, Patrick J F; Branson, Sonya; Chen, Nigel T M; Van Bockstaele, Bram; Salemink, Elske; MacLeod, Colin; Notebaert, Lies

    2017-12-01

    Attention bias modification (ABM) procedures have shown promise as a therapeutic intervention, however current ABM procedures have proven inconsistent in their ability to reliably achieve the requisite change in attentional bias needed to produce emotional benefits. This highlights the need to better understand the precise task conditions that facilitate the intended change in attention bias in order to realise the therapeutic potential of ABM procedures. Based on the observation that change in attentional bias occurs largely outside conscious awareness, the aim of the current study was to determine if an ABM procedure delivered under conditions likely to preclude explicit awareness of the experimental contingency, via the addition of a working memory load, would contribute to greater change in attentional bias. Bias change was assessed among 122 participants in response to one of four ABM tasks given by the two experimental factors of ABM training procedure delivered either with or without working memory load, and training direction of either attend-negative or avoid-negative. Findings revealed that avoid-negative ABM procedure under working memory load resulted in significantly greater reductions in attentional bias compared to the equivalent no-load condition. The current findings will require replication with clinical samples to determine the utility of the current task for achieving emotional benefits. These present findings are consistent with the position that the addition of a working memory load may facilitate change in attentional bias in response to an ABM training procedure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Attribution bias and social anxiety in schizophrenia

    Directory of Open Access Journals (Sweden)

    Amelie M. Achim

    2016-06-01

    Full Text Available Studies on attribution biases in schizophrenia have produced mixed results, whereas such biases have been more consistently reported in people with anxiety disorders. Anxiety comorbidities are frequent in schizophrenia, in particular social anxiety disorder, which could influence their patterns of attribution biases. The objective of the present study was thus to determine if individuals with schizophrenia and a comorbid social anxiety disorder (SZ+ show distinct attribution biases as compared with individuals with schizophrenia without social anxiety (SZ− and healthy controls. Attribution biases were assessed with the Internal, Personal, and Situational Attributions Questionnaire in 41 individual with schizophrenia and 41 healthy controls. Results revealed the lack of the normal externalizing bias in SZ+, whereas SZ− did not significantly differ from healthy controls on this dimension. The personalizing bias was not influenced by social anxiety but was in contrast linked with delusions, with a greater personalizing bias in individuals with current delusions. Future studies on attribution biases in schizophrenia should carefully document symptom presentation, including social anxiety.

  11. Biased Brownian dynamics for rate constant calculation.

    OpenAIRE

    Zou, G; Skeel, R D; Subramaniam, S

    2000-01-01

    An enhanced sampling method-biased Brownian dynamics-is developed for the calculation of diffusion-limited biomolecular association reaction rates with high energy or entropy barriers. Biased Brownian dynamics introduces a biasing force in addition to the electrostatic force between the reactants, and it associates a probability weight with each trajectory. A simulation loses weight when movement is along the biasing force and gains weight when movement is against the biasing force. The sampl...

  12. The coalitional value theory of antigay bias

    NARCIS (Netherlands)

    Winegard, Bo; Reynolds, Tania; Baumeister, Roy F.; Plant, E. Ashby

    2016-01-01

    Research indicates that antigay bias follows a specific pattern (and probably has throughout written history, at least in the West): (a) men evince more antigay bias than women; (b) men who belong to traditionally male coalitions evince more antigay bias than those who do not; (c) antigay bias is

  13. Dynamically biased statistical model for the ortho/para conversion in the H2 + H3+ → H3+ + H2 reaction.

    Science.gov (United States)

    Gómez-Carrasco, Susana; González-Sánchez, Lola; Aguado, Alfredo; Sanz-Sanz, Cristina; Zanchet, Alexandre; Roncero, Octavio

    2012-09-07

    In this work we present a dynamically biased statistical model to describe the evolution of the title reaction from statistical to a more direct mechanism, using quasi-classical trajectories (QCT). The method is based on the one previously proposed by Park and Light [J. Chem. Phys. 126, 044305 (2007)]. A recent global potential energy surface is used here to calculate the capture probabilities, instead of the long-range ion-induced dipole interactions. The dynamical constraints are introduced by considering a scrambling matrix which depends on energy and determine the probability of the identity/hop/exchange mechanisms. These probabilities are calculated using QCT. It is found that the high zero-point energy of the fragments is transferred to the rest of the degrees of freedom, what shortens the lifetime of H(5)(+) complexes and, as a consequence, the exchange mechanism is produced with lower proportion. The zero-point energy (ZPE) is not properly described in quasi-classical trajectory calculations and an approximation is done in which the initial ZPE of the reactants is reduced in QCT calculations to obtain a new ZPE-biased scrambling matrix. This reduction of the ZPE is explained by the need of correcting the pure classical level number of the H(5)(+) complex, as done in classical simulations of unimolecular processes and to get equivalent quantum and classical rate constants using Rice-Ramsperger-Kassel-Marcus theory. This matrix allows to obtain a ratio of hop/exchange mechanisms, α(T), in rather good agreement with recent experimental results by Crabtree et al. [J. Chem. Phys. 134, 194311 (2011)] at room temperature. At lower temperatures, however, the present simulations predict too high ratios because the biased scrambling matrix is not statistical enough. This demonstrates the importance of applying quantum methods to simulate this reaction at the low temperatures of astrophysical interest.

  14. Symmetry as Bias: Rediscovering Special Relativity

    Science.gov (United States)

    Lowry, Michael R.

    1992-01-01

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

  15. Computers and conversation

    CERN Document Server

    Luff, Paul; Gilbert, Nigel G

    1986-01-01

    In the past few years a branch of sociology, conversation analysis, has begun to have a significant impact on the design of human*b1computer interaction (HCI). The investigation of human*b1human dialogue has emerged as a fruitful foundation for interactive system design.****This book includes eleven original chapters by leading researchers who are applying conversation analysis to HCI. The fundamentals of conversation analysis are outlined, a number of systems are described, and a critical view of their value for HCI is offered.****Computers and Conversation will be of interest to all concerne

  16. Anti-Bias Education: Reflections

    Science.gov (United States)

    Derman-Sparks, Louise

    2011-01-01

    It is 30 years since NAEYC published "Anti-Bias Curriculum Tools for Empowering Young Children" (Derman-Sparks & ABC Task Force, 1989). Since then, anti-bias education concepts have become part of the early childhood education (ECE) narrative in the United States and many other countries. It has brought a fresh way of thinking about…

  17. ZOMG - I. How the cosmic web inhibits halo growth and generates assembly bias

    Science.gov (United States)

    Borzyszkowski, Mikolaj; Porciani, Cristiano; Romano-Díaz, Emilio; Garaldi, Enrico

    2017-07-01

    The clustering of dark matter haloes with fixed mass depends on their formation history, an effect known as assembly bias. We use zoom N-body simulations to investigate the origin of this phenomenon. For each halo at redshift z = 0, we determine the time in which the physical volume containing its final mass becomes stable. We consider five examples for which this happens at z ˜ 1.5 and two that do not stabilize by z = 0. The zoom simulations show that early-collapsing haloes do not grow in mass at z = 0 while late-forming ones show a net inflow. The reason is that 'accreting' haloes are located at the nodes of a network of thin filaments feeding them. Conversely, each 'stalled' halo lies within a prominent filament that is thicker than the halo size. Infalling material from the surroundings becomes part of the filament while matter within it recedes from the halo. We conclude that assembly bias originates from quenching halo growth due to tidal forces following the formation of non-linear structures in the cosmic web, as previously conjectured in the literature. Also the internal dynamics of the haloes change: the velocity anisotropy profile is biased towards radial (tangential) orbits in accreting (stalled) haloes. Our findings reveal the cause of the yet unexplained dependence of halo clustering on the anisotropy. Finally, we extend the excursion-set theory to account for these effects. A simple criterion based on the ellipticity of the linear tidal field combined with the spherical-collapse model provides excellent predictions for both classes of haloes.

  18. Sampler bias -- Phase 1

    International Nuclear Information System (INIS)

    Blanchard, R.J.

    1995-01-01

    This documents Phase 1 determinations on sampler induced bias for four sampler types used in tank characterization. Each sampler, grab sampler or bottle-on-a-string, auger sampler, sludge sampler and universal sampler, is briefly discussed and their physical limits noted. Phase 2 of this document will define additional testing and analysis to further define Sampler Bias

  19. Negativity Bias in Dangerous Drivers.

    Directory of Open Access Journals (Sweden)

    Jing Chai

    Full Text Available The behavioral and cognitive characteristics of dangerous drivers differ significantly from those of safe drivers. However, differences in emotional information processing have seldom been investigated. Previous studies have revealed that drivers with higher anger/anxiety trait scores are more likely to be involved in crashes and that individuals with higher anger traits exhibit stronger negativity biases when processing emotions compared with control groups. However, researchers have not explored the relationship between emotional information processing and driving behavior. In this study, we examined the emotional information processing differences between dangerous drivers and safe drivers. Thirty-eight non-professional drivers were divided into two groups according to the penalty points that they had accrued for traffic violations: 15 drivers with 6 or more points were included in the dangerous driver group, and 23 drivers with 3 or fewer points were included in the safe driver group. The emotional Stroop task was used to measure negativity biases, and both behavioral and electroencephalograph data were recorded. The behavioral results revealed stronger negativity biases in the dangerous drivers than in the safe drivers. The bias score was correlated with self-reported dangerous driving behavior. Drivers with strong negativity biases reported having been involved in mores crashes compared with the less-biased drivers. The event-related potentials (ERPs revealed that the dangerous drivers exhibited reduced P3 components when responding to negative stimuli, suggesting decreased inhibitory control of information that is task-irrelevant but emotionally salient. The influence of negativity bias provides one possible explanation of the effects of individual differences on dangerous driving behavior and traffic crashes.

  20. Religious Attitudes and Home Bias

    OpenAIRE

    C. Reggiani; G. Rossini

    2008-01-01

    Home bias affects trade in goods, services and financial assets. It is mostly generated by "natural" trade barriers. Among these dividers we may list many behavioral and sociological factors, such as status quo biases and a few kind of ‘embeddedness’. Unfortunately these factors are difficult to measure. An important part of ‘embeddedness’ may be related to religious attitudes. Is there any relation between economic home bias and religious attitudes at the individual tier? Our aim is to provi...

  1. Placebo effect studies are susceptible to response bias and to other types of biases

    DEFF Research Database (Denmark)

    Hróbjartsson, Asbjørn; Kaptchuk, Ted J; Miller, Franklin G

    2011-01-01

    Investigations of the effect of placebo are often challenging to conduct and interpret. The history of placebo shows that assessment of its clinical significance has a real potential to be biased. We analyze and discuss typical types of bias in studies on placebo....

  2. A Comparison of attentional biases and memory biases in social phobia and major depression

    NARCIS (Netherlands)

    Rinck, M.; Becker, E.S.

    2005-01-01

    Cognitive processes play an important role in the etiology and maintenance of anxiety and depression. Current theories differ, however, in their predictions regarding the occurrence of attentional biases and memory biases in depression and anxiety. To allow for a systematic comparison of disorders

  3. Elements of energy conversion

    CERN Document Server

    Russell, Charles R

    2013-01-01

    Elements of Energy Conversion brings together scattered information on the subject of energy conversion and presents it in terms of the fundamental thermodynamics that apply to energy conversion by any process. Emphasis is given to the development of the theory of heat engines because these are and will remain most important power sources. Descriptive material is then presented to provide elementary information on all important energy conversion devices. The book contains 10 chapters and opens with a discussion of forms of energy, energy sources and storage, and energy conversion. This is foll

  4. Are most samples of animals systematically biased? Consistent individual trait differences bias samples despite random sampling.

    Science.gov (United States)

    Biro, Peter A

    2013-02-01

    Sampling animals from the wild for study is something nearly every biologist has done, but despite our best efforts to obtain random samples of animals, 'hidden' trait biases may still exist. For example, consistent behavioral traits can affect trappability/catchability, independent of obvious factors such as size and gender, and these traits are often correlated with other repeatable physiological and/or life history traits. If so, systematic sampling bias may exist for any of these traits. The extent to which this is a problem, of course, depends on the magnitude of bias, which is presently unknown because the underlying trait distributions in populations are usually unknown, or unknowable. Indeed, our present knowledge about sampling bias comes from samples (not complete population censuses), which can possess bias to begin with. I had the unique opportunity to create naturalized populations of fish by seeding each of four small fishless lakes with equal densities of slow-, intermediate-, and fast-growing fish. Using sampling methods that are not size-selective, I observed that fast-growing fish were up to two-times more likely to be sampled than slower-growing fish. This indicates substantial and systematic bias with respect to an important life history trait (growth rate). If correlations between behavioral, physiological and life-history traits are as widespread as the literature suggests, then many animal samples may be systematically biased with respect to these traits (e.g., when collecting animals for laboratory use), and affect our inferences about population structure and abundance. I conclude with a discussion on ways to minimize sampling bias for particular physiological/behavioral/life-history types within animal populations.

  5. Adaptable history biases in human perceptual decisions.

    Science.gov (United States)

    Abrahamyan, Arman; Silva, Laura Luz; Dakin, Steven C; Carandini, Matteo; Gardner, Justin L

    2016-06-21

    When making choices under conditions of perceptual uncertainty, past experience can play a vital role. However, it can also lead to biases that worsen decisions. Consistent with previous observations, we found that human choices are influenced by the success or failure of past choices even in a standard two-alternative detection task, where choice history is irrelevant. The typical bias was one that made the subject switch choices after a failure. These choice history biases led to poorer performance and were similar for observers in different countries. They were well captured by a simple logistic regression model that had been previously applied to describe psychophysical performance in mice. Such irrational biases seem at odds with the principles of reinforcement learning, which would predict exquisite adaptability to choice history. We therefore asked whether subjects could adapt their irrational biases following changes in trial order statistics. Adaptability was strong in the direction that confirmed a subject's default biases, but weaker in the opposite direction, so that existing biases could not be eradicated. We conclude that humans can adapt choice history biases, but cannot easily overcome existing biases even if irrational in the current context: adaptation is more sensitive to confirmatory than contradictory statistics.

  6. Phenotypic shift in Pseudomonas aeruginosa populations from cystic fibrosis lungs after 2-week antipseudomonal treatment

    DEFF Research Database (Denmark)

    Fernandez-Barat, Laia; Ciofu, Oana; Kragh, Kasper N.

    2017-01-01

    ) colony-forming units (CFU/mL), b) frequency of mucoids and non-mucoids, c) resistance pattern to anti-pseudomonal drugs, d) hypermutability, e) transcriptomic profiles, and f) presence of biofilms. Results We collected 23 sputum samples (12 before antibiotic treatment and 11 after) and 77 P. aeruginosa...

  7. Domain wall engineering through exchange bias

    International Nuclear Information System (INIS)

    Albisetti, E.; Petti, D.

    2016-01-01

    The control of the structure and position of magnetic domain walls is at the basis of the development of different magnetic devices and architectures. Several nanofabrication techniques have been proposed to geometrically confine and shape domain wall structures; however, a fine tuning of the position and micromagnetic configuration is hardly achieved, especially in continuous films. This work shows that, by controlling the unidirectional anisotropy of a continuous ferromagnetic film through exchange bias, domain walls whose spin arrangement is generally not favored by dipolar and exchange interactions can be created. Micromagnetic simulations reveal that the domain wall width, position and profile can be tuned by establishing an abrupt change in the direction and magnitude of the exchange bias field set in the system. - Highlights: • Micromagnetic simulations study domain walls in exchange biased thin films. • Novel domain wall configurations can be stabilized via exchange bias. • Domain walls nucleate at the boundary of regions with different exchange bias. • Domain wall width and spin profile are controlled by tuning the exchange bias.

  8. How we categorize objects is related to how we remember them: The shape bias as a memory bias.

    Science.gov (United States)

    Vlach, Haley A

    2016-12-01

    The "shape bias" describes the phenomenon that, after a certain point in development, children and adults generalize object categories based on shape to a greater degree than other perceptual features. The focus of research on the shape bias has been to examine the types of information that learners attend to in one moment in time. The current work takes a different approach by examining whether learners' categorical biases are related to their retention of information across time. In three experiments, children's (N=72) and adults' (N=240) memory performance for features of objects was examined in relation to their categorical biases. The results of these experiments demonstrated that the number of shape matches chosen during the shape bias task significantly predicted shape memory. Moreover, children and adults with a shape bias were more likely to remember the shape of objects than the color and size of objects. Taken together, this work suggests that the development of a shape bias may engender better memory for shape information. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Is bias in the eye of the beholder? A vignette study to assess recognition of cognitive biases in clinical case workups.

    Science.gov (United States)

    Zwaan, Laura; Monteiro, Sandra; Sherbino, Jonathan; Ilgen, Jonathan; Howey, Betty; Norman, Geoffrey

    2017-02-01

    Many authors have implicated cognitive biases as a primary cause of diagnostic error. If this is so, then physicians already familiar with common cognitive biases should consistently identify biases present in a clinical workup. The aim of this paper is to determine whether physicians agree on the presence or absence of particular biases in a clinical case workup and how case outcome knowledge affects bias identification. We conducted a web survey of 37 physicians. Each participant read eight cases and listed which biases were present from a list provided. In half the cases the outcome implied a correct diagnosis; in the other half, it implied an incorrect diagnosis. We compared the number of biases identified when the outcome implied a correct or incorrect primary diagnosis. Additionally, the agreement among participants about presence or absence of specific biases was assessed. When the case outcome implied a correct diagnosis, an average of 1.75 cognitive biases were reported; when incorrect, 3.45 biases (F=71.3, p<0.00001). Individual biases were reported from 73% to 125% more often when an incorrect diagnosis was implied. There was no agreement on presence or absence of individual biases, with κ ranging from 0.000 to 0.044. Individual physicians are unable to agree on the presence or absence of individual cognitive biases. Their judgements are heavily influenced by hindsight bias; when the outcome implies a diagnostic error, twice as many biases are identified. The results present challenges for current error reduction strategies based on identification of cognitive biases. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  10. Iterated multidimensional wave conversion

    International Nuclear Information System (INIS)

    Brizard, A. J.; Tracy, E. R.; Johnston, D.; Kaufman, A. N.; Richardson, A. S.; Zobin, N.

    2011-01-01

    Mode conversion can occur repeatedly in a two-dimensional cavity (e.g., the poloidal cross section of an axisymmetric tokamak). We report on two novel concepts that allow for a complete and global visualization of the ray evolution under iterated conversions. First, iterated conversion is discussed in terms of ray-induced maps from the two-dimensional conversion surface to itself (which can be visualized in terms of three-dimensional rooms). Second, the two-dimensional conversion surface is shown to possess a symplectic structure derived from Dirac constraints associated with the two dispersion surfaces of the interacting waves.

  11. AC bias operation of the perpendicular biased ferrite tuned cavity for the TRIUMF KAON Factory booster synchrotron

    International Nuclear Information System (INIS)

    Poirier, R.L.; Enegren, T.A.; Enchevich, I.B.

    1991-05-01

    The RF cavity for the booster synchrotron requires a frequency swing from 46 MHz at a repetition rate of 50 Hz and a maximum accelerating gap voltage of 65 kV. A DC biased prototype cavity built at LANL using perpendicular-biased yttrium-garnet ferrites, rather than the more conventional parallel-biased NiZn ferrites, has now undergone major reconstruction at TRIUMF for AC bias operation. RF signal level measurements have shown that the frequency swing at a repetition rate of 50 Hz can be accomplished and still handle the eddy current losses in the cavity structures with minimal effect on the magnetizing field. The prototype cavity is now undergoing high power RF tests with full power AC bias operation. The results of these tests and operational experience is reported. (Author) ref., 6 figs

  12. SNP discovery in nonmodel organisms: strand bias and base-substitution errors reduce conversion rates.

    Science.gov (United States)

    Gonçalves da Silva, Anders; Barendse, William; Kijas, James W; Barris, Wes C; McWilliam, Sean; Bunch, Rowan J; McCullough, Russell; Harrison, Blair; Hoelzel, A Rus; England, Phillip R

    2015-07-01

    Single nucleotide polymorphisms (SNPs) have become the marker of choice for genetic studies in organisms of conservation, commercial or biological interest. Most SNP discovery projects in nonmodel organisms apply a strategy for identifying putative SNPs based on filtering rules that account for random sequencing errors. Here, we analyse data used to develop 4723 novel SNPs for the commercially important deep-sea fish, orange roughy (Hoplostethus atlanticus), to assess the impact of not accounting for systematic sequencing errors when filtering identified polymorphisms when discovering SNPs. We used SAMtools to identify polymorphisms in a velvet assembly of genomic DNA sequence data from seven individuals. The resulting set of polymorphisms were filtered to minimize 'bycatch'-polymorphisms caused by sequencing or assembly error. An Illumina Infinium SNP chip was used to genotype a final set of 7714 polymorphisms across 1734 individuals. Five predictors were examined for their effect on the probability of obtaining an assayable SNP: depth of coverage, number of reads that support a variant, polymorphism type (e.g. A/C), strand-bias and Illumina SNP probe design score. Our results indicate that filtering out systematic sequencing errors could substantially improve the efficiency of SNP discovery. We show that BLASTX can be used as an efficient tool to identify single-copy genomic regions in the absence of a reference genome. The results have implications for research aiming to identify assayable SNPs and build SNP genotyping assays for nonmodel organisms. © 2014 John Wiley & Sons Ltd.

  13. delta-biased Josephson tunnel junctions

    DEFF Research Database (Denmark)

    Monaco, R.; Mygind, Jesper; Koshelet, V.

    2010-01-01

    Abstract: The behavior of a long Josephson tunnel junction drastically depends on the distribution of the dc bias current. We investigate the case in which the bias current is fed in the central point of a one-dimensional junction. Such junction configuration has been recently used to detect...... the persistent currents circulating in a superconducting loop. Analytical and numerical results indicate that the presence of fractional vortices leads to remarkable differences from the conventional case of uniformly distributed dc bias current. The theoretical findings are supported by detailed measurements...

  14. The immitigable nature of assembly bias: the impact of halo definition on assembly bias

    Science.gov (United States)

    Villarreal, Antonio S.; Zentner, Andrew R.; Mao, Yao-Yuan; Purcell, Chris W.; van den Bosch, Frank C.; Diemer, Benedikt; Lange, Johannes U.; Wang, Kuan; Campbell, Duncan

    2017-11-01

    Dark matter halo clustering depends not only on halo mass, but also on other properties such as concentration and shape. This phenomenon is known broadly as assembly bias. We explore the dependence of assembly bias on halo definition, parametrized by spherical overdensity parameter, Δ. We summarize the strength of concentration-, shape-, and spin-dependent halo clustering as a function of halo mass and halo definition. Concentration-dependent clustering depends strongly on mass at all Δ. For conventional halo definitions (Δ ∼ 200 - 600 m), concentration-dependent clustering at low mass is driven by a population of haloes that is altered through interactions with neighbouring haloes. Concentration-dependent clustering can be greatly reduced through a mass-dependent halo definition with Δ ∼ 20 - 40 m for haloes with M200 m ≲ 1012 h-1M⊙. Smaller Δ implies larger radii and mitigates assembly bias at low mass by subsuming altered, so-called backsplash haloes into now larger host haloes. At higher masses (M200 m ≳ 1013 h-1M⊙) larger overdensities, Δ ≳ 600 m, are necessary. Shape- and spin-dependent clustering are significant for all halo definitions that we explore and exhibit a relatively weaker mass dependence. Generally, both the strength and the sense of assembly bias depend on halo definition, varying significantly even among common definitions. We identify no halo definition that mitigates all manifestations of assembly bias. A halo definition that mitigates assembly bias based on one halo property (e.g. concentration) must be mass dependent. The halo definitions that best mitigate concentration-dependent halo clustering do not coincide with the expected average splashback radii at fixed halo mass.

  15. Is racial bias malleable? Whites' lay theories of racial bias predict divergent strategies for interracial interactions.

    Science.gov (United States)

    Neel, Rebecca; Shapiro, Jenessa R

    2012-07-01

    How do Whites approach interracial interactions? We argue that a previously unexamined factor-beliefs about the malleability of racial bias-guides Whites' strategies for difficult interracial interactions. We predicted and found that those who believe racial bias is malleable favor learning-oriented strategies such as taking the other person's perspective and trying to learn why an interaction is challenging, whereas those who believe racial bias is fixed favor performance-oriented strategies such as overcompensating in the interaction and trying to end the interaction as quickly as possible. Four studies support these predictions. Whether measured (Studies 1, 3, and 4) or manipulated (Study 2), beliefs that racial bias is fixed versus malleable yielded these divergent strategies for difficult interracial interactions. Furthermore, beliefs about the malleability of racial bias are distinct from related constructs (e.g., prejudice and motivations to respond without prejudice; Studies 1, 3, and 4) and influence self-reported (Studies 1-3) and actual (Study 4) strategies in imagined (Studies 1-2) and real (Studies 3-4) interracial interactions. Together, these findings demonstrate that beliefs about the malleability of racial bias influence Whites' approaches to and strategies within interracial interactions. PsycINFO Database Record (c) 2012 APA, all rights reserved

  16. Attention bias to emotional information in children as a function of maternal emotional disorders and maternal attention biases.

    Science.gov (United States)

    Waters, Allison M; Forrest, Kylee; Peters, Rosie-Mae; Bradley, Brendan P; Mogg, Karin

    2015-03-01

    Children of parents with emotional disorders have an increased risk for developing anxiety and depressive disorders. Yet the mechanisms that contribute to this increased risk are poorly understood. The present study aimed to examine attention biases in children as a function of maternal lifetime emotional disorders and maternal attention biases. There were 134 participants, including 38 high-risk children, and their mothers who had lifetime emotional disorders; and 29 low-risk children, and their mothers without lifetime emotional disorders. Mothers and children completed a visual probe task with emotional face pairs presented for 500 ms. Attention bias in children did not significantly differ solely as a function of whether or not their mothers had lifetime emotional disorders. However, attention bias in high-risk children was significantly related to their mothers' attention bias. Specifically, children of mothers with lifetime emotional disorders showed a greater negative attention bias if their mothers had a greater tendency to direct attention away from positive information. This study was cross-sectional in nature, and therefore unable to assess long-term predictive effects. Also, just one exposure duration of 500 ms was utilised. Attention bias for negative information is greater in offspring of mothers who have lifetime emotional disorders and a reduced positive bias, which could be a risk marker for the development of emotional disorders in children.

  17. Does neurocognitive function affect cognitive bias toward an emotional stimulus? Association between general attentional ability and attentional bias toward threat

    Directory of Open Access Journals (Sweden)

    Yuko eHakamata

    2014-08-01

    Full Text Available Background: Although poorer cognitive performance has been found to be associated with anxiety, it remains unclear whether neurocognitive function affects biased cognitive processing toward emotional information. We investigated whether general cognitive function evaluated with a standard neuropsychological test predicts biased cognition, focusing on attentional bias toward threat.Methods: One hundred and five healthy young adults completed a dot-probe task measuring attentional bias and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS measuring general cognitive function, which consists of five domains: immediate memory, visuospatial/constructional, language, attention, and delayed memory. Stepwise multiple regression analysis was performed to examine the relationships between attentional bias and cognitive function. Results: The attentional domain was the best predictor of attentional bias toward threat (β = -0.26, p = 0.006. Within the attentional domain, digit symbol coding was negatively correlated with attentional bias (r = -0.28, p = 0.005.Conclusions: The present study provides the first evidence that general attentional ability, which was assessed with a standard neuropsychological test, affects attentional bias toward threatening information. Individual cognitive profiles might be important for the measurement and modification of cognitive biases.

  18. Cognitive Biases and Nonverbal Cue Availability in Detecting Deception

    Science.gov (United States)

    Burgoon, Judee K.; Blair, J. Pete; Strom, Renee E.

    2008-01-01

    In potentially deceptive situations, people rely on mental shortcuts to help process information. These heuristic judgments are often biased and result in inaccurate assessments of sender veracity. Four such biases--truth bias, visual bias, demeanor bias, and expectancy violation bias--were examined in a judgment experiment that varied nonverbal…

  19. The evolution of social learning rules: payoff-biased and frequency-dependent biased transmission.

    Science.gov (United States)

    Kendal, Jeremy; Giraldeau, Luc-Alain; Laland, Kevin

    2009-09-21

    Humans and other animals do not use social learning indiscriminately, rather, natural selection has favoured the evolution of social learning rules that make selective use of social learning to acquire relevant information in a changing environment. We present a gene-culture coevolutionary analysis of a small selection of such rules (unbiased social learning, payoff-biased social learning and frequency-dependent biased social learning, including conformism and anti-conformism) in a population of asocial learners where the environment is subject to a constant probability of change to a novel state. We define conditions under which each rule evolves to a genetically polymorphic equilibrium. We find that payoff-biased social learning may evolve under high levels of environmental variation if the fitness benefit associated with the acquired behaviour is either high or low but not of intermediate value. In contrast, both conformist and anti-conformist biases can become fixed when environment variation is low, whereupon the mean fitness in the population is higher than for a population of asocial learners. Our examination of the population dynamics reveals stable limit cycles under conformist and anti-conformist biases and some highly complex dynamics including chaos. Anti-conformists can out-compete conformists when conditions favour a low equilibrium frequency of the learned behaviour. We conclude that evolution, punctuated by the repeated successful invasion of different social learning rules, should continuously favour a reduction in the equilibrium frequency of asocial learning, and propose that, among competing social learning rules, the dominant rule will be the one that can persist with the lowest frequency of asocial learning.

  20. Infrared up-conversion microscope

    DEFF Research Database (Denmark)

    2014-01-01

    There is presented an up-conversion infrared microscope (110) arranged for imaging an associated object (130), wherein the up-conversion infrared microscope (110) comprises a non-linear crystal (120) arranged for up-conversion of infrared electromagnetic radiation, and wherein an objective optical...

  1. Infrared up-conversion telescope

    DEFF Research Database (Denmark)

    2014-01-01

    There is presented to an up-conversion infrared telescope (110) arranged for imaging an associated scene (130), wherein the up-conversion infrared telescope (110) comprises a non-linear crystal (120) arranged for up-conversion of infrared electromagnetic radiation, and wherein a first optical...

  2. Study of the Dependency on Magnetic Field and Bias Voltage of an AC-Biased TES Microcalorimeter

    Science.gov (United States)

    Gottardi, L.; Bruijn, M.; denHartog, R.; Hoevers, H.; deKorte, P.; vanderKuur, J.; Linderman, M.; Adams, J.; Bailey, C.; Bandler, S.; hide

    2012-01-01

    At SRON we are studying the performance of a Goddard Space Flight Center single pixel TES microcalorimeter operated in an AC bias configuration. For x-ray photons at 6 keV the pixel shows an x-ray energy resolution Delta E(sub FWHM) = 3.7 eV, which is about a factor 2 worse than the energy resolution observed in an identical DC-biased pixel. In order to better understand the reasons for this discrepancy we characterized the detector as a function of temperature, bias working point and applied perpendicular magnetic field. A strong periodic dependency of the detector noise on the TES AC bias voltage is measured. We discuss the results in the framework of the recently observed weak-link behaviour of a TES microcalorimeter.

  3. Critical Thinking and Cognitive Bias

    Directory of Open Access Journals (Sweden)

    Jeffrey Maynes

    2015-05-01

    Full Text Available Teaching critical thinking skill is a central pedagogical aim in many courses. These skills, it is hoped, will be both portable (applicable in a wide range of contexts and durable (not forgotten quickly. Yet, both of these virtues are challenged by pervasive and potent cognitive biases, such as motivated reasoning, false consensus bias and hindsight bias. In this paper, I argue that a focus on the development of metacognitive skill shows promise as a means to inculcate debiasing habits in students. Such habits will help students become more critical reasoners. I close with suggestions for implementing this strategy.

  4. Numerical value biases sound localization.

    Science.gov (United States)

    Golob, Edward J; Lewald, Jörg; Getzmann, Stephan; Mock, Jeffrey R

    2017-12-08

    Speech recognition starts with representations of basic acoustic perceptual features and ends by categorizing the sound based on long-term memory for word meaning. However, little is known about whether the reverse pattern of lexical influences on basic perception can occur. We tested for a lexical influence on auditory spatial perception by having subjects make spatial judgments of number stimuli. Four experiments used pointing or left/right 2-alternative forced choice tasks to examine perceptual judgments of sound location as a function of digit magnitude (1-9). The main finding was that for stimuli presented near the median plane there was a linear left-to-right bias for localizing smaller-to-larger numbers. At lateral locations there was a central-eccentric location bias in the pointing task, and either a bias restricted to the smaller numbers (left side) or no significant number bias (right side). Prior number location also biased subsequent number judgments towards the opposite side. Findings support a lexical influence on auditory spatial perception, with a linear mapping near midline and more complex relations at lateral locations. Results may reflect coding of dedicated spatial channels, with two representing lateral positions in each hemispace, and the midline area represented by either their overlap or a separate third channel.

  5. Non-Gaussian halo assembly bias

    International Nuclear Information System (INIS)

    Reid, Beth A.; Verde, Licia; Dolag, Klaus; Matarrese, Sabino; Moscardini, Lauro

    2010-01-01

    The strong dependence of the large-scale dark matter halo bias on the (local) non-Gaussianity parameter, f NL , offers a promising avenue towards constraining primordial non-Gaussianity with large-scale structure surveys. In this paper, we present the first detection of the dependence of the non-Gaussian halo bias on halo formation history using N-body simulations. We also present an analytic derivation of the expected signal based on the extended Press-Schechter formalism. In excellent agreement with our analytic prediction, we find that the halo formation history-dependent contribution to the non-Gaussian halo bias (which we call non-Gaussian halo assembly bias) can be factorized in a form approximately independent of redshift and halo mass. The correction to the non-Gaussian halo bias due to the halo formation history can be as large as 100%, with a suppression of the signal for recently formed halos and enhancement for old halos. This could in principle be a problem for realistic galaxy surveys if observational selection effects were to pick galaxies occupying only recently formed halos. Current semi-analytic galaxy formation models, for example, imply an enhancement in the expected signal of ∼ 23% and ∼ 48% for galaxies at z = 1 selected by stellar mass and star formation rate, respectively

  6. A Model for Conversation

    DEFF Research Database (Denmark)

    Ayres, Phil

    2012-01-01

    This essay discusses models. It examines what models are, the roles models perform and suggests various intentions that underlie their construction and use. It discusses how models act as a conversational partner, and how they support various forms of conversation within the conversational activity...

  7. Attentional Bias towards Positive Emotion Predicts Stress Resilience.

    Science.gov (United States)

    Thoern, Hanna A; Grueschow, Marcus; Ehlert, Ulrike; Ruff, Christian C; Kleim, Birgit

    2016-01-01

    There is extensive evidence for an association between an attentional bias towards emotionally negative stimuli and vulnerability to stress-related psychopathology. Less is known about whether selective attention towards emotionally positive stimuli relates to mental health and stress resilience. The current study used a modified Dot Probe task to investigate if individual differences in attentional biases towards either happy or angry emotional stimuli, or an interaction between these biases, are related to self-reported trait stress resilience. In a nonclinical sample (N = 43), we indexed attentional biases as individual differences in reaction time for stimuli preceded by either happy or angry (compared to neutral) face stimuli. Participants with greater attentional bias towards happy faces (but not angry faces) reported higher trait resilience. However, an attentional bias towards angry stimuli moderated this effect: The attentional bias towards happy faces was only predictive for resilience in those individuals who also endorsed an attentional bias towards angry stimuli. An attentional bias towards positive emotional stimuli may thus be a protective factor contributing to stress resilience, specifically in those individuals who also endorse an attentional bias towards negative emotional stimuli. Our findings therefore suggest a novel target for prevention and treatment interventions addressing stress-related psychopathology.

  8. Minimum Bias Trigger in ATLAS

    International Nuclear Information System (INIS)

    Kwee, Regina

    2010-01-01

    Since the restart of the LHC in November 2009, ATLAS has collected inelastic pp collisions to perform first measurements on charged particle densities. These measurements will help to constrain various models describing phenomenologically soft parton interactions. Understanding the trigger efficiencies for different event types are therefore crucial to minimize any possible bias in the event selection. ATLAS uses two main minimum bias triggers, featuring complementary detector components and trigger levels. While a hardware based first trigger level situated in the forward regions with 2.2 < |η| < 3.8 has been proven to select pp-collisions very efficiently, the Inner Detector based minimum bias trigger uses a random seed on filled bunches and central tracking detectors for the event selection. Both triggers were essential for the analysis of kinematic spectra of charged particles. Their performance and trigger efficiency measurements as well as studies on possible bias sources will be presented. We also highlight the advantage of these triggers for particle correlation analyses. (author)

  9. Is there bias in editorial choice? Yes

    OpenAIRE

    Moustafa, Khaled

    2018-01-01

    Nature has recently published a Correspondence claiming the absence of fame biases in the editorial choice. The topic is interesting and deserves a deeper analysis than it was presented because the reported brief analysis and its conclusion are somewhat biased for many reasons, some of them are discussed here. Since the editorial assessment is a form of peer-review, the biases reported on external peer-reviews would, thus, apply to the editorial assessment, too. The biases would be proportion...

  10. Australia's Bond Home Bias

    OpenAIRE

    Anil V. Mishra; Umaru B. Conteh

    2014-01-01

    This paper constructs the float adjusted measure of home bias and explores the determinants of bond home bias by employing the International Monetary Fund's high quality dataset (2001 to 2009) on cross-border bond investment. The paper finds that Australian investors' prefer investing in countries with higher economic development and more developed bond markets. Exchange rate volatility appears to be an impediment for cross-border bond investment. Investors prefer investing in countries with ...

  11. Salutary effects of an attention bias modification mobile application on biobehavioral measures of stress and anxiety during pregnancy.

    Science.gov (United States)

    Dennis-Tiwary, Tracy A; Denefrio, Samantha; Gelber, Shari

    2017-07-01

    Stress and anxiety during pregnancy are associated with a range of adverse health outcomes, but there is an unmet need for low-barrier treatments that target stress and anxiety. One such treatment approach, attention bias modification training (ABMT), targets the anxiety-related threat bias, a disruption in attention to and neural processing of threat-related information. It remains unclear, however, whether reducing treatment barriers via mobile delivery of ABMT is effective and whether ABMT efficacy varies depending on individual differences in neural processing of threat. The present study tested whether mobile, gamified ABMT reduced prenatal threat bias, anxiety and stress, and whether ABMT efficacy varied with individual differences in neural responses to threat. Participants were 29 women in their 19th-29th week of pregnancy, randomized to four weeks of an ABMT or placebo training (PT) version of the mobile app using a double-blind design. Self-report of anxiety, depression, and stress were obtained; salivary cortisol was collected at home and in lab in response to stressors to index biological stress reactivity. Threat bias was measured using a computerized attention assay during which EEG was recorded to generate event-related potentials (ERPs) to threat cues. Results showed lower levels of lab cortisol following ABMT versus PT. Although the main effect of ABMT on subjective anxiety was not significant, the magnitude of cortisol reduction was correlated with lower levels of subjective anxiety and threat bias. Those receiving ABMT also reported less anxiety when showing smaller ERPs to threat (P1, P2) prior to training, but, conversely reported more anxiety when showing larger ERPs to threat. Use of gamified, mobile ABMT reduced biobehavioral indices of prenatal stress and anxiety, but effects on anxiety varied with individual differences in cortisol response and neurocognitive indices of early attention to threat. Copyright © 2017 Elsevier B.V. All rights

  12. Systematic biases in human heading estimation.

    Directory of Open Access Journals (Sweden)

    Luigi F Cuturi

    Full Text Available Heading estimation is vital to everyday navigation and locomotion. Despite extensive behavioral and physiological research on both visual and vestibular heading estimation over more than two decades, the accuracy of heading estimation has not yet been systematically evaluated. Therefore human visual and vestibular heading estimation was assessed in the horizontal plane using a motion platform and stereo visual display. Heading angle was overestimated during forward movements and underestimated during backward movements in response to both visual and vestibular stimuli, indicating an overall multimodal bias toward lateral directions. Lateral biases are consistent with the overrepresentation of lateral preferred directions observed in neural populations that carry visual and vestibular heading information, including MSTd and otolith afferent populations. Due to this overrepresentation, population vector decoding yields patterns of bias remarkably similar to those observed behaviorally. Lateral biases are inconsistent with standard bayesian accounts which predict that estimates should be biased toward the most common straight forward heading direction. Nevertheless, lateral biases may be functionally relevant. They effectively constitute a perceptual scale expansion around straight ahead which could allow for more precise estimation and provide a high gain feedback signal to facilitate maintenance of straight-forward heading during everyday navigation and locomotion.

  13. The Accuracy Enhancing Effect of Biasing Cues

    NARCIS (Netherlands)

    W. Vanhouche (Wouter); S.M.J. van Osselaer (Stijn)

    2009-01-01

    textabstractExtrinsic cues such as price and irrelevant attributes have been shown to bias consumers’ product judgments. Results in this article replicate those findings in pretrial judgments but show that such biasing cues can improve quality judgments at a later point in time. Initially biasing

  14. Journal of Biosciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Seeding dispersal is an active detachment exhibit in aging Pseudomonas aeruginosa biofilm. Yet, effect factors of this process in the biofilm of clinical isolated mucoid P. aeruginosa strain remain to be better characterized. In our previous work, one mucoid P. earuginosa strain PA17 was isolated from a patient with recurrent ...

  15. How we categorize objects is related to how we remember them: The shape bias as a memory bias

    Science.gov (United States)

    Vlach, Haley A.

    2016-01-01

    The “shape bias” describes the phenomenon that, after a certain point in development, children and adults generalize object categories based upon shape to a greater degree than other perceptual features. The focus of research on the shape bias has been to examine the types of information that learners attend to in one moment in time. The current work takes a different approach by examining whether learners' categorical biases are related to their retention of information across time. In three experiments, children's (N = 72) and adults' (N = 240) memory performance for features of objects was examined in relation to their categorical biases. The results of these experiments demonstrated that the number of shape matches chosen during the shape bias task significantly predicted shape memory. Moreover, children and adults with a shape bias were more likely to remember the shape of objects than they were the color and size of objects. Taken together, this work suggests the development of a shape bias may engender better memory for shape information. PMID:27454236

  16. Positioning of Weight Bias: Moving towards Social Justice.

    Science.gov (United States)

    Nutter, Sarah; Russell-Mayhew, Shelly; Alberga, Angela S; Arthur, Nancy; Kassan, Anusha; Lund, Darren E; Sesma-Vazquez, Monica; Williams, Emily

    2016-01-01

    Weight bias is a form of stigma with detrimental effects on the health and wellness of individuals with large bodies. Researchers from various disciplines have recognized weight bias as an important topic for public health and for professional practice. To date, researchers from various areas have approached weight bias from independent perspectives and from differing theoretical orientations. In this paper, we examined the similarities and differences between three perspectives (i.e., weight-centric, non-weight-centric (health-centric), and health at every size) used to understand weight bias and approach weight bias research with regard to (a) language about people with large bodies, (b) theoretical position, (c) identified consequences of weight bias, and (d) identified influences on weight-based social inequity. We suggest that, despite differences, each perspective acknowledges the negative influences that position weight as being within individual control and the negative consequences of weight bias. We call for recognition and discussion of weight bias as a social justice issue in order to change the discourse and professional practices extended towards individuals with large bodies. We advocate for an emphasis on social justice as a uniting framework for interdisciplinary research on weight bias.

  17. An inclusive taxonomy of behavioral biases

    OpenAIRE

    David Peón; Manel Antelo; Anxo Calvo-Silvosa

    2017-01-01

    This paper overviews the theoretical and empirical research on behavioral biases and their influence in the literature. To provide a systematic exposition, we present a unified framework that takes the reader through an original taxonomy, based on the reviews of relevant authors in the field. In particular, we establish three broad categories that may be distinguished: heuristics and biases; choices, values and frames; and social factors. We then describe the main biases within each category,...

  18. Four questions and a conversation: Can theory enrich conversation partner training?

    DEFF Research Database (Denmark)

    Pound, Carole; Ahlsén, Elisabeth; Simmons-Mackie, NIna

    Background and aimsConversation partner training (CPT) is an umbrella term for different approaches to intervention aiming to facilitate and improve communication between people with aphasia (PWA) and their conversation partners (CP). Some approaches are grounded in a bottom-up approach...... and interactions. Philosophically informed by existential-phenomenological perspectives, the humanisation framework encourages reflection on what practices can make people feel more (or less) human. Reviewing experiences of conversation against the eight suggested dimensions of what it means to be human may offer...

  19. Direct Conversion of Energy.

    Science.gov (United States)

    Corliss, William R.

    This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Direct energy conversion involves energy transformation without moving parts. The concepts of direct and dynamic energy conversion plus the laws governing energy conversion are investigated. Among the topics…

  20. Cognitive biases can affect moral intuitions about cognitive enhancement

    Directory of Open Access Journals (Sweden)

    Lucius eCaviola

    2014-10-01

    Full Text Available Research into cognitive biases that impair human judgment has mostly been applied to the area of economic decision-making. Ethical decision-making has been comparatively neglected. Since ethical decisions often involve very high individual as well as collective stakes, analyzing how cognitive biases affect them can be expected to yield important results. In this theoretical article, we consider the ethical debate about cognitive enhancement (CE and suggest a number of cognitive biases that are likely to affect moral intuitions and judgments about CE: status quo bias, loss aversion, risk aversion, omission bias, scope insensitivity, nature bias, and optimistic bias. We find that there are more well-documented biases that are likely to cause irrational aversion to CE than biases in the opposite direction. This suggests that common attitudes about CE are predominantly negatively biased. Within this new perspective, we hope that subsequent research will be able to elaborate this hypothesis and develop effective de-biasing techniques that can help increase the rationality of the public CE debate and thus improve our ethical decision-making.

  1. Energy conversion statics

    CERN Document Server

    Messerle, H K; Declaris, Nicholas

    2013-01-01

    Energy Conversion Statics deals with equilibrium situations and processes linking equilibrium states. A development of the basic theory of energy conversion statics and its applications is presented. In the applications the emphasis is on processes involving electrical energy. The text commences by introducing the general concept of energy with a survey of primary and secondary energy forms, their availability, and use. The second chapter presents the basic laws of energy conversion. Four postulates defining the overall range of applicability of the general theory are set out, demonstrating th

  2. Uranium Conversion & Enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-06

    The isotopes of uranium that are found in nature, and hence in ‘fresh’ Yellowcake’, are not in relative proportions that are suitable for power or weapons applications. The goal of conversion then is to transform the U3O8 yellowcake into UF6. Conversion and enrichment of uranium is usually required to obtain material with enough 235U to be usable as fuel in a reactor or weapon. The cost, size, and complexity of practical conversion and enrichment facilities aid in nonproliferation by design.

  3. Freely flowing conversations

    DEFF Research Database (Denmark)

    Aakjær, Marie Kirstejn; Andrade, David; Dexters, Peter

    and in regards to rehabilitation efforts. In the context of prisons UDI is inspired by the complexity approach (Stacey 2005). We seek to facilitate freely flowing conversations between inmates, staff and managers – pushing the boundaries of existing norms, roles and beliefs. In the end however we rely...... relations by changing conversations. Through the theoretical framework of the complexity approach, we discuss how this may lead to organizational change. Finally we suggest that inviting inmates to take part in conversations about core organizational development may be a fundamental strategy in trying...

  4. Political conversations on Facebook

    DEFF Research Database (Denmark)

    Sørensen, Mads P.

    2016-01-01

    Political conversations are according to theories on deliberative democracy essential to well-functioning democracies. Traditionally these conversations have taken place in face-to-face settings, in e.g. party meetings and town meetings. However, social media such as Facebook and Twitter offers new...... possibilities for online political conversations between citizens and politicians. This paper examines the presence on Facebook and Twitter of Members of the Danish national Parliament, the Folketing, and focusses on a quantitative mapping of the political conversation activities taking place in the threads...... following Facebook posts from Danish Members of Parliament (MPs). The paper shows that, in comparison with previous findings from other countries, Danish MPs have a relatively high degree of engagement in political conversations with citizens on Facebook – and that a large number of citizens follow MPs...

  5. Determination and Correction of Persistent Biases in Quantum Annealers

    Science.gov (United States)

    2016-08-25

    for all of the qubits. Narrowing of the bias distribution. To show the correctability of the persistent biases , we ran the experiment described above...this is a promising application for bias correction . Importantly, while the J biases determined here are in general smaller than the h biases , numerical...1Scientific RepoRts | 6:18628 | DOI: 10.1038/srep18628 www.nature.com/scientificreports Determination and correction of persistent biases in quantum

  6. Does neurocognitive function affect cognitive bias toward an emotional stimulus? Association between general attentional ability and attentional bias toward threat

    OpenAIRE

    Hakamata, Yuko; Matsui, Mie; Tagaya, Hirokuni

    2014-01-01

    Background: Although poorer cognitive performance has been found to be associated with anxiety, it remains unclear whether neurocognitive function affects biased cognitive processing toward emotional information. We investigated whether general cognitive function evaluated with a standard neuropsychological test predicts biased cognition, focusing on attentional bias toward threat. Methods: One hundred and five healthy young adults completed a dot-probe task measuring attentional bias and ...

  7. Production bias and cluster annihilation: Why necessary?

    DEFF Research Database (Denmark)

    Singh, B.N.; Trinkaus, H.; Woo, C.H.

    1994-01-01

    the primary cluster density is high. Therefore, a sustained high swelling rate driven by production bias must involve the annihilation of primary clusters at sinks. A number of experimental observations which are unexplainable in terms of the conventional dislocation bias for monointerstitials is considered......-field approach. The production bias approach, on the other hand, is based on the physical features of the cascade damage and is therefore considered to be more appropriate for describing the damage accumulation under cascade damage conditions. However, production bias can not produce high a swelling rate when....... It is found that the production bias and cluster annihilation are necessary to explain these observations, with, in many cases, the explicit consideration of the annihilation of the primary interstitial clusters....

  8. Approach-Induced Biases in Human Information Sampling.

    Directory of Open Access Journals (Sweden)

    Laurence T Hunt

    2016-11-01

    Full Text Available Information sampling is often biased towards seeking evidence that confirms one's prior beliefs. Despite such biases being a pervasive feature of human behavior, their underlying causes remain unclear. Many accounts of these biases appeal to limitations of human hypothesis testing and cognition, de facto evoking notions of bounded rationality, but neglect more basic aspects of behavioral control. Here, we investigated a potential role for Pavlovian approach in biasing which information humans will choose to sample. We collected a large novel dataset from 32,445 human subjects, making over 3 million decisions, who played a gambling task designed to measure the latent causes and extent of information-sampling biases. We identified three novel approach-related biases, formalized by comparing subject behavior to a dynamic programming model of optimal information gathering. These biases reflected the amount of information sampled ("positive evidence approach", the selection of which information to sample ("sampling the favorite", and the interaction between information sampling and subsequent choices ("rejecting unsampled options". The prevalence of all three biases was related to a Pavlovian approach-avoid parameter quantified within an entirely independent economic decision task. Our large dataset also revealed that individual differences in the amount of information gathered are a stable trait across multiple gameplays and can be related to demographic measures, including age and educational attainment. As well as revealing limitations in cognitive processing, our findings suggest information sampling biases reflect the expression of primitive, yet potentially ecologically adaptive, behavioral repertoires. One such behavior is sampling from options that will eventually be chosen, even when other sources of information are more pertinent for guiding future action.

  9. [Conversation analysis for improving nursing communication].

    Science.gov (United States)

    Yi, Myungsun

    2007-08-01

    Nursing communication has become more important than ever before because quality of nursing services largely depends on the quality of communication in a very competitive health care environment. This article was to introduce ways to improve nursing communication using conversation analysis. This was a review study on conversation analysis, critically examining previous studies in nursing communication and interpersonal relationships. This study provided theoretical backgrounds and basic assumptions of conversation analysis which was influenced by ethnomethodology, phenomenology, and sociolinguistic. In addition, the characteristics and analysis methods of conversation analysis were illustrated in detail. Lastly, how conversation analysis could help improve communication was shown, by examining researches using conversation analysis not only for ordinary conversations but also for extraordinary or difficult conversations such as conversations between patients with dementia and their professional nurses. Conversation analysis can help in improving nursing communication by providing various structures and patterns as well as prototypes of conversation, and by suggesting specific problems and problem-solving strategies in communication.

  10. Gender bias affects forests worldwide

    Science.gov (United States)

    Marlène Elias; Susan S Hummel; Bimbika S Basnett; Carol J.P. Colfer

    2017-01-01

    Gender biases persist in forestry research and practice. These biases result in reduced scientific rigor and inequitable, ineffective, and less efficient policies, programs, and interventions. Drawing from a two-volume collection of current and classic analyses on gender in forests, we outline five persistent and inter-related themes: gendered governance, tree tenure,...

  11. A thermalization energy analysis of the threshold voltage shift in amorphous indium gallium zinc oxide thin film transistors under simultaneous negative gate bias and illumination

    Energy Technology Data Exchange (ETDEWEB)

    Flewitt, A. J., E-mail: ajf@eng.cam.ac.uk [Electrical Engineering Division, Cambridge University, J J Thomson Avenue, Cambridge CB3 0FA (United Kingdom); Powell, M. J. [252, Valley Drive, Kendal LA9 7SL (United Kingdom)

    2014-04-07

    It has been previously observed that thin film transistors (TFTs) utilizing an amorphous indium gallium zinc oxide (a-IGZO) semiconducting channel suffer from a threshold voltage shift when subjected to a negative gate bias and light illumination simultaneously. In this work, a thermalization energy analysis has been applied to previously published data on negative bias under illumination stress (NBIS) in a-IGZO TFTs. A barrier to defect conversion of 0.65–0.75 eV is extracted, which is consistent with reported energies of oxygen vacancy migration. The attempt-to-escape frequency is extracted to be 10{sup 6}−10{sup 7} s{sup −1}, which suggests a weak localization of carriers in band tail states over a 20–40 nm distance. Models for the NBIS mechanism based on charge trapping are reviewed and a defect pool model is proposed in which two distinct distributions of defect states exist in the a-IGZO band gap: these are associated with states that are formed as neutrally charged and 2+ charged oxygen vacancies at the time of film formation. In this model, threshold voltage shift is not due to a defect creation process, but to a change in the energy distribution of states in the band gap upon defect migration as this allows a state formed as a neutrally charged vacancy to be converted into one formed as a 2+ charged vacancy and vice versa. Carrier localization close to the defect migration site is necessary for the conversion process to take place, and such defect migration sites are associated with conduction and valence band tail states. Under negative gate bias stressing, the conduction band tail is depleted of carriers, but the bias is insufficient to accumulate holes in the valence band tail states, and so no threshold voltage shift results. It is only under illumination that the quasi Fermi level for holes is sufficiently lowered to allow occupation of valence band tail states. The resulting charge localization then allows a negative threshold voltage

  12. Weight bias internalization across weight categories among school-aged children. Validation of the Weight Bias Internalization Scale for Children.

    Science.gov (United States)

    Zuba, Anna; Warschburger, Petra

    2018-06-01

    Anti-fat bias is widespread and is linked to the internalization of weight bias and psychosocial problems. The purpose of this study was to examine the internalization of weight bias among children across weight categories and to evaluate the psychometric properties of the Weight Bias Internalization Scale for Children (WBIS-C). Data were collected from 1484 primary school children and their parents. WBIS-C demonstrated good internal consistency (α = .86) after exclusion of Item 1. The unitary factor structure was supported using exploratory and confirmatory factor analyses (factorial validity). Girls and overweight children reported higher WBIS-C scores in comparison to boys and non-overweight peers (known-groups validity). Convergent validity was shown by significant correlations with psychosocial problems. Internalization of weight bias explained additional variance in different indicators of psychosocial well-being. The results suggest that the WBIS-C is a psychometrically sound and informative tool to assess weight bias internalization among children. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Contamination effects on fixed-bias Langmuir probes

    Energy Technology Data Exchange (ETDEWEB)

    Steigies, C. T. [Institut fuer Experimentelle und Angewandte Physik, Christian-Albrechts-Universitaet zu Kiel, 24098 Kiel (Germany); Barjatya, A. [Department of Physical Sciences, Embry-Riddle Aeronautical University, Daytona Beach, Florida 32114 (United States)

    2012-11-15

    Langmuir probes are standard instruments for plasma density measurements on many sounding rockets. These probes can be operated in swept-bias as well as in fixed-bias modes. In swept-bias Langmuir probes, contamination effects are frequently visible as a hysteresis between consecutive up and down voltage ramps. This hysteresis, if not corrected, leads to poorly determined plasma densities and temperatures. With a properly chosen sweep function, the contamination parameters can be determined from the measurements and correct plasma parameters can then be determined. In this paper, we study the contamination effects on fixed-bias Langmuir probes, where no hysteresis type effect is seen in the data. Even though the contamination is not evident from the measurements, it does affect the plasma density fluctuation spectrum as measured by the fixed-bias Langmuir probe. We model the contamination as a simple resistor-capacitor circuit between the probe surface and the plasma. We find that measurements of small scale plasma fluctuations (meter to sub-meter scale) along a rocket trajectory are not affected, but the measured amplitude of large scale plasma density variation (tens of meters or larger) is attenuated. From the model calculations, we determine amplitude and cross-over frequency of the contamination effect on fixed-bias probes for different contamination parameters. The model results also show that a fixed bias probe operating in the ion-saturation region is affected less by contamination as compared to a fixed bias probe operating in the electron saturation region.

  14. Origination, expansion, evolutionary trajectory, and expression bias of AP2/ERF superfamily in Brassica napus

    Directory of Open Access Journals (Sweden)

    Xiaoming Song

    2016-08-01

    Full Text Available The AP2/ERF superfamily, one of the most important transcription factor families, plays crucial roles in response to biotic and abiotic stresses. So far, a comprehensive evolutionary inference of its origination and expansion has not been available. Here, we identified 515 AP2/ERF genes in B. napus, a neo-tetraploid forming ~7500 years ago, and found that 82.14% of them were duplicated in the tetraploidization. A prominent subgenome bias was revealed in gene expression, tissue-specific, and gene conversion. Moreover, a large-scale analysis across plants and alga suggested that this superfamily could have been originated from AP2 family, expanding to form other families (ERF, and RAV. This process was accompanied by duplicating and/or alternative deleting AP2 domain, intragenic domain sequence conversion, and/or by acquiring other domains, resulting in copy number variations, alternatively contributing to functional innovation. We found that significant positive selection occurred at certain critical nodes during the evolution of land plants, possibly responding to changing environment. In conclusion, the present research revealed origination, functional innovation, and evolutionary trajectory of the AP2/ERF superfamily, contributing to understanding their roles in plant stress tolerance.

  15. Heuristic Biases in Mathematical Reasoning

    Science.gov (United States)

    Inglis, Matthew; Simpson, Adrian

    2005-01-01

    In this paper we briefly describe the dual process account of reasoning, and explain the role of heuristic biases in human thought. Concentrating on the so-called matching bias effect, we describe a piece of research that indicates a correlation between success at advanced level mathematics and an ability to override innate and misleading…

  16. Improved Correction of Misclassification Bias With Bootstrap Imputation.

    Science.gov (United States)

    van Walraven, Carl

    2018-07-01

    Diagnostic codes used in administrative database research can create bias due to misclassification. Quantitative bias analysis (QBA) can correct for this bias, requires only code sensitivity and specificity, but may return invalid results. Bootstrap imputation (BI) can also address misclassification bias but traditionally requires multivariate models to accurately estimate disease probability. This study compared misclassification bias correction using QBA and BI. Serum creatinine measures were used to determine severe renal failure status in 100,000 hospitalized patients. Prevalence of severe renal failure in 86 patient strata and its association with 43 covariates was determined and compared with results in which renal failure status was determined using diagnostic codes (sensitivity 71.3%, specificity 96.2%). Differences in results (misclassification bias) were then corrected with QBA or BI (using progressively more complex methods to estimate disease probability). In total, 7.4% of patients had severe renal failure. Imputing disease status with diagnostic codes exaggerated prevalence estimates [median relative change (range), 16.6% (0.8%-74.5%)] and its association with covariates [median (range) exponentiated absolute parameter estimate difference, 1.16 (1.01-2.04)]. QBA produced invalid results 9.3% of the time and increased bias in estimates of both disease prevalence and covariate associations. BI decreased misclassification bias with increasingly accurate disease probability estimates. QBA can produce invalid results and increase misclassification bias. BI avoids invalid results and can importantly decrease misclassification bias when accurate disease probability estimates are used.

  17. Affective Biases in Humans and Animals.

    Science.gov (United States)

    Robinson, E S J; Roiser, J P

    Depression is one of the most common but poorly understood psychiatric conditions. Although drug treatments and psychological therapies are effective in some patients, many do not achieve full remission and some patients receive no apparent benefit. Developing new improved treatments requires a better understanding of the aetiology of symptoms and evaluation of novel therapeutic targets in pre-clinical studies. Recent developments in our understanding of the basic cognitive processes that may contribute to the development of depression and its treatment offer new opportunities for both clinical and pre-clinical research. This chapter discusses the clinical evidence supporting a cognitive neuropsychological model of depression and antidepressant efficacy, and how this information may be usefully translated to pre-clinical investigation. Studies using neuropsychological tests in depressed patients and at risk populations have revealed basic negative emotional biases and disrupted reward and punishment processing, which may also impact on non-affective cognition. These affective biases are sensitive to antidepressant treatments with early onset effects observed, suggesting an important role in recovery. This clinical work into affective biases has also facilitated back-translation to animals and the development of assays to study affective biases in rodents. These animal studies suggest that, similar to humans, rodents in putative negative affective states exhibit negative affective biases on decision-making and memory tasks. Antidepressant treatments also induce positive biases in these rodent tasks, supporting the translational validity of this approach. Although still in the early stages of development and validation, affective biases in depression have the potential to offer new insights into the clinical condition, as well as facilitating the development of more translational approaches for pre-clinical studies.

  18. Biased managers, organizational design, and incentive provision

    OpenAIRE

    Moreira, Humberto Ataíde; Costa, Cristiano Machado; Ferreira, Daniel Bernardo Soares

    2004-01-01

    Rio de Janeiro We model the tradeoff between the balance and the strength of incentives implicit in the choice between hierarchical and matrix organizational structures. We show that managerial biases determine which structure is optimal: hierarchical forms are preferred when biases are low, while matrix structures are preferred when biases are high.

  19. Study on the effect of measuring methods on incident photon-to-electron conversion efficiency of dye-sensitized solar cells by home-made setup

    Science.gov (United States)

    Guo, Xiao-Zhi; Luo, Yan-Hong; Zhang, Yi-Duo; Huang, Xiao-Chun; Li, Dong-Mei; Meng, Qing-Bo

    2010-10-01

    An experimental setup is built for the measurement of monochromatic incident photon-to-electron conversion efficiency (IPCE) of solar cells. With this setup, three kinds of IPCE measuring methods as well as the convenient switching between them are achieved. The setup can also measure the response time and waveform of the short-circuit current of solar cell. Using this setup, IPCE results of dye-sensitized solar cells (DSCs) are determined and compared under different illumination conditions with each method. It is found that the IPCE values measured by AC method involving the lock-in technique are sincerely influenced by modulation frequency and bias illumination. Measurements of the response time and waveform of short-circuit current have revealed that this effect can be explained by the slow response of DSCs. To get accurate IPCE values by this method, the measurement should be carried out with a low modulation frequency and under bias illumination. The IPCE values measured by DC method under the bias light illumination will be disturbed since the short-circuit current increased with time continuously due to the temperature rise of DSC. Therefore, temperature control of DSC is considered necessary for IPCE measurement especially in DC method with bias light illumination. Additionally, high bias light intensity (>2 sun) is found to decrease the IPCE values due to the ion transport limitation of the electrolyte.

  20. Study on the effect of measuring methods on incident photon-to-electron conversion efficiency of dye-sensitized solar cells by home-made setup.

    Science.gov (United States)

    Guo, Xiao-Zhi; Luo, Yan-Hong; Zhang, Yi-Duo; Huang, Xiao-Chun; Li, Dong-Mei; Meng, Qing-Bo

    2010-10-01

    An experimental setup is built for the measurement of monochromatic incident photon-to-electron conversion efficiency (IPCE) of solar cells. With this setup, three kinds of IPCE measuring methods as well as the convenient switching between them are achieved. The setup can also measure the response time and waveform of the short-circuit current of solar cell. Using this setup, IPCE results of dye-sensitized solar cells (DSCs) are determined and compared under different illumination conditions with each method. It is found that the IPCE values measured by AC method involving the lock-in technique are sincerely influenced by modulation frequency and bias illumination. Measurements of the response time and waveform of short-circuit current have revealed that this effect can be explained by the slow response of DSCs. To get accurate IPCE values by this method, the measurement should be carried out with a low modulation frequency and under bias illumination. The IPCE values measured by DC method under the bias light illumination will be disturbed since the short-circuit current increased with time continuously due to the temperature rise of DSC. Therefore, temperature control of DSC is considered necessary for IPCE measurement especially in DC method with bias light illumination. Additionally, high bias light intensity (>2 sun) is found to decrease the IPCE values due to the ion transport limitation of the electrolyte.

  1. Biases in Visual, Auditory, and Audiovisual Perception of Space

    Science.gov (United States)

    Odegaard, Brian; Wozny, David R.; Shams, Ladan

    2015-01-01

    Localization of objects and events in the environment is critical for survival, as many perceptual and motor tasks rely on estimation of spatial location. Therefore, it seems reasonable to assume that spatial localizations should generally be accurate. Curiously, some previous studies have reported biases in visual and auditory localizations, but these studies have used small sample sizes and the results have been mixed. Therefore, it is not clear (1) if the reported biases in localization responses are real (or due to outliers, sampling bias, or other factors), and (2) whether these putative biases reflect a bias in sensory representations of space or a priori expectations (which may be due to the experimental setup, instructions, or distribution of stimuli). Here, to address these questions, a dataset of unprecedented size (obtained from 384 observers) was analyzed to examine presence, direction, and magnitude of sensory biases, and quantitative computational modeling was used to probe the underlying mechanism(s) driving these effects. Data revealed that, on average, observers were biased towards the center when localizing visual stimuli, and biased towards the periphery when localizing auditory stimuli. Moreover, quantitative analysis using a Bayesian Causal Inference framework suggests that while pre-existing spatial biases for central locations exert some influence, biases in the sensory representations of both visual and auditory space are necessary to fully explain the behavioral data. How are these opposing visual and auditory biases reconciled in conditions in which both auditory and visual stimuli are produced by a single event? Potentially, the bias in one modality could dominate, or the biases could interact/cancel out. The data revealed that when integration occurred in these conditions, the visual bias dominated, but the magnitude of this bias was reduced compared to unisensory conditions. Therefore, multisensory integration not only improves the

  2. Biases in Visual, Auditory, and Audiovisual Perception of Space.

    Directory of Open Access Journals (Sweden)

    Brian Odegaard

    2015-12-01

    Full Text Available Localization of objects and events in the environment is critical for survival, as many perceptual and motor tasks rely on estimation of spatial location. Therefore, it seems reasonable to assume that spatial localizations should generally be accurate. Curiously, some previous studies have reported biases in visual and auditory localizations, but these studies have used small sample sizes and the results have been mixed. Therefore, it is not clear (1 if the reported biases in localization responses are real (or due to outliers, sampling bias, or other factors, and (2 whether these putative biases reflect a bias in sensory representations of space or a priori expectations (which may be due to the experimental setup, instructions, or distribution of stimuli. Here, to address these questions, a dataset of unprecedented size (obtained from 384 observers was analyzed to examine presence, direction, and magnitude of sensory biases, and quantitative computational modeling was used to probe the underlying mechanism(s driving these effects. Data revealed that, on average, observers were biased towards the center when localizing visual stimuli, and biased towards the periphery when localizing auditory stimuli. Moreover, quantitative analysis using a Bayesian Causal Inference framework suggests that while pre-existing spatial biases for central locations exert some influence, biases in the sensory representations of both visual and auditory space are necessary to fully explain the behavioral data. How are these opposing visual and auditory biases reconciled in conditions in which both auditory and visual stimuli are produced by a single event? Potentially, the bias in one modality could dominate, or the biases could interact/cancel out. The data revealed that when integration occurred in these conditions, the visual bias dominated, but the magnitude of this bias was reduced compared to unisensory conditions. Therefore, multisensory integration not only

  3. Understanding and Overcoming Implicit Gender Bias in Plastic Surgery.

    Science.gov (United States)

    Phillips, Nicole A; Tannan, Shruti C; Kalliainen, Loree K

    2016-11-01

    Although explicit sex-based discrimination has largely been deemed unacceptable in professional settings, implicit gender bias persists and results in a significant lack of parity in plastic surgery and beyond. Implicit gender bias is the result of a complex interplay of cultural and societal expectations, learned behaviors, and standardized associations. As such, both male and female surgeons are subject to its influence. A review of the literature was conducted, examining theories of gender bias, current manifestations of gender bias in plastic surgery and other fields, and interventions designed to address gender bias. Multiple studies demonstrate persistent gender bias that impacts female physicians at all levels of training. Several institutions have enacted successful interventions to identify and address gender bias. Explicit gender bias has largely disappeared, yet unconscious or implicit gender bias persists. A wide-scale commitment to addressing implicit gender bias in plastic surgery is necessary and overdue. Recommendations include immediate actions that can be undertaken on an individual basis, and changes that should be implemented at a national and international level by leaders in the field.

  4. Galaxy bias and primordial non-Gaussianity

    Energy Technology Data Exchange (ETDEWEB)

    Assassi, Valentin; Baumann, Daniel [DAMTP, Cambridge University, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Schmidt, Fabian, E-mail: assassi@ias.edu, E-mail: D.D.Baumann@uva.nl, E-mail: fabians@MPA-Garching.MPG.DE [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85748 Garching (Germany)

    2015-12-01

    We present a systematic study of galaxy biasing in the presence of primordial non-Gaussianity. For a large class of non-Gaussian initial conditions, we define a general bias expansion and prove that it is closed under renormalization, thereby showing that the basis of operators in the expansion is complete. We then study the effects of primordial non-Gaussianity on the statistics of galaxies. We show that the equivalence principle enforces a relation between the scale-dependent bias in the galaxy power spectrum and that in the dipolar part of the bispectrum. This provides a powerful consistency check to confirm the primordial origin of any observed scale-dependent bias. Finally, we also discuss the imprints of anisotropic non-Gaussianity as motivated by recent studies of higher-spin fields during inflation.

  5. Galaxy bias and primordial non-Gaussianity

    International Nuclear Information System (INIS)

    Assassi, Valentin; Baumann, Daniel; Schmidt, Fabian

    2015-01-01

    We present a systematic study of galaxy biasing in the presence of primordial non-Gaussianity. For a large class of non-Gaussian initial conditions, we define a general bias expansion and prove that it is closed under renormalization, thereby showing that the basis of operators in the expansion is complete. We then study the effects of primordial non-Gaussianity on the statistics of galaxies. We show that the equivalence principle enforces a relation between the scale-dependent bias in the galaxy power spectrum and that in the dipolar part of the bispectrum. This provides a powerful consistency check to confirm the primordial origin of any observed scale-dependent bias. Finally, we also discuss the imprints of anisotropic non-Gaussianity as motivated by recent studies of higher-spin fields during inflation

  6. Bias changing molecule–lead couple and inducing low bias negative differential resistance for electrons acceptor predicted by first-principles study

    International Nuclear Information System (INIS)

    Min, Y.; Fang, J.H.; Zhong, C.G.; Dong, Z.C.; Zhao, Z.Y.; Zhou, P.X.; Yao, K.L.

    2015-01-01

    A first-principles study of the transport properties of 3,13-dimercaptononacene–6,21-dione molecule sandwiched between two gold leads is reported. The strong effect of negative differential resistance with large peak-to-valley ratio of 710% is present under low bias. We found that bias can change molecule–lead couple and induce low bias negative differential resistance for electrons acceptor, which may promise the potential applications in molecular devices with low-power dissipation in the future. - Highlights: • Acceptor is constructed to negative differential resistor (NDR). • NDR effect is present under low bias. • Bias change molecule–lead couple and induce NDR effect

  7. Mechanism for and method of biasing magnetic sensor

    Science.gov (United States)

    Kautz, David R.

    2007-12-04

    A magnetic sensor package having a biasing mechanism involving a coil-generated, resistor-controlled magnetic field for providing a desired biasing effect. In a preferred illustrated embodiment, the package broadly comprises a substrate; a magnetic sensor element; a biasing mechanism, including a coil and a first resistance element; an amplification mechanism; a filter capacitor element; and an encapsulant. The sensor is positioned within the coil. A current applied to the coil produces a biasing magnetic field. The biasing magnetic field is controlled by selecting a resistance value for the first resistance element which achieves the desired biasing effect. The first resistance element preferably includes a plurality of selectable resistors, the selection of one or more of which sets the resistance value.

  8. Postoperative conversion disorder.

    Science.gov (United States)

    Afolabi, Kola; Ali, Sameer; Gahtan, Vivian; Gorji, Reza; Li, Fenghua; Nussmeier, Nancy A

    2016-05-01

    Conversion disorder is a psychiatric disorder in which psychological stress causes neurologic deficits. A 28-year-old female surgical patient had uneventful general anesthesia and emergence but developed conversion disorder 1 hour postoperatively. She reported difficulty speaking, right-hand numbness and weakness, and right-leg paralysis. Neurologic examination and imaging revealed no neuronal damage, herniation, hemorrhage, or stroke. The patient mentioned failing examinations the day before surgery and discontinuing her prescribed antidepressant medication, leading us to diagnose conversion disorder, with eventual confirmation by neuroimaging and follow-up examinations. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Uranium conversion wastes

    International Nuclear Information System (INIS)

    Vicente, R.; Dellamano, J.C.

    1989-12-01

    A set of mathematical equations was developed and used to estimate the radiological significance of each radionuclide potentially present in the uranium refining industry effluents. The equations described the evolution in time of the radionuclides activities in the uranium fuel cycle, from mining and milling, through the yellowcake, till the conversion effluents. Some radionuclides that are not usually monitored in conversion effluents (e.g. Pa-231 and Ac-227) were found to be potentially relevant from the radiological point of view in conversion facilities, and are certainly relevant in mining and milling industry, at least in a few waste streams. (author) [pt

  10. 5 CFR 317.302 - Conversion procedures.

    Science.gov (United States)

    2010-01-01

    ... conversion. (2) Pay. Upon conversion to the Senior Executive Service, an employee's SES rate will be... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Conversion procedures. 317.302 Section... IN THE SENIOR EXECUTIVE SERVICE Conversion to the Senior Executive Service § 317.302 Conversion...

  11. Dynamically biased statistical model for the ortho/para conversion in the H2 + H3+ → H3+ + H2 reaction

    OpenAIRE

    Gómez-Carrasco, Susana; González-Sánchez, Lola; Aguado, Alfredo; Sanz-Sanz, Cristina; Zanchet, Alexandre; Roncero, Octavio

    2012-01-01

    In this work we present a dynamically biased statistical model to describe the evolution of the title reaction from statistical to a more direct mechanism, using quasi-classical trajectories (QCT). The method is based on the one previously proposed by Park and Light [J. Chem. Phys. 126, 044305 (2007)10.1063/1.2430711]. A recent global potential energy surface is used here to calculate the capture probabilities, instead of the long-range ion-induced dipole interactions. The dynamical constrain...

  12. Mood-congruent free recall bias in anxious individuals is not a consequence of response bias.

    Science.gov (United States)

    Russo, Riccardo; Whittuck, Dora; Roberson, Debi; Dutton, Kevin; Georgiou, George; Fox, Elaine

    2006-05-01

    The status of mood-congruent free recall bias in anxious individuals was evaluated following incidental encoding of target words. Individuals with high and low levels of trait anxiety completed a modified Stroop task, which revealed an attentional bias for threat-related stimuli in anxious individuals. This group was significantly slower in naming the colour in which threat-related words were displayed compared to neutral words. In a subsequent free recall test for the words used in the modified Stroop task, anxious individuals recalled more threat-related words compared to low-anxious people. This difference was significant even when controlling for the false recall of items that had not been presented during study. These results support the view put forward by Russo, Fox, Bellinger, and Nguyen-Van-Tam (2001) that mood-congruent free recall bias in anxious individuals can be observed if the target material is encoded at a relatively shallow level. Moreover, contrary to Dowens and Calvo (2003), the current results show that the memory advantage for threat-related information in anxious individuals is not a consequence of response bias.

  13. White and Black American Children’s Implicit Intergroup Bias

    Science.gov (United States)

    Newheiser, Anna-Kaisa; Olson, Kristina R.

    2011-01-01

    Despite a decline in explicit prejudice, adults and children from majority groups (e.g., White Americans) often express bias implicitly, as assessed by the Implicit Association Test. In contrast, minority-group (e.g., Black American) adults on average show no bias on the IAT. In the present research, representing the first empirical investigation of whether Black children’s IAT responses parallel those of Black adults, we examined implicit bias in 7–11-year-old White and Black American children. Replicating previous findings with adults, whereas White children showed a robust ingroup bias, Black children showed no bias. Additionally, we investigated the role of valuing status in the development of implicit bias. For Black children, explicit preference for high status predicted implicit outgroup bias: Black children who explicitly expressed high preference for rich (vs. poor) people showed an implicit preference for Whites comparable in magnitude to White children’s ingroup bias. Implications for research on intergroup bias are discussed. PMID:22184478

  14. Direct testing of the biasing effect of manipulations of endolymphatic pressure on cochlear mechanical function

    Science.gov (United States)

    LePage, Eric; Avan, Paul

    2015-12-01

    The history of cochlear mechanical investigations has been carried out in two largely separate sets of endeavours; those interested in auditory processing in animal models and those interested in the origin of adverse vestibular symptoms in humans. In respect of the first, mechanical vibratory data is considered pathological and not representative of pristine behaviour if it departs from the reigning model of sharp tuning and high hearing sensitivity. Conversely, when the description of the pathological behaviour is the focus, fluid movements responsible for hearing loss and vestibular symptoms dominate. Yet both extensive sets of data possess a common factor now being reconsidered for its potential to shed light on the mechanisms in general. The common factor is a mechanical bias — the departure of cochlear epithelial membranes from their usual resting position. In both cases the bias modulates hearing sensitivity and distorts tuning characteristics. Indeed several early sets of guinea pig mechanical data were dismissed as "pathological" when in hindsight, the primary effect influencing the data was not loss of outer hair cell function per se, but a mechanical bias unknowingly introduced in process of making the measurement. Such biases in the displacement of the basilar membrane from its position are common, and may be caused by low-frequency sounds (topically including infrasound) or by variations in fluid volume in the chambers particularly applying the case of endolymphatic hydrops. Most biases are quantified in terms of visualisation of fluid volume change, electric potential changes and otoacoustic emissions. Notably many previous studies have also searched for raised pressures with negative results. Yet these repeated findings are contrary to the widespread notion that, at least when homeostasis is lost, it is a rise in endolymphatic pressure which is responsible for membrane rupture and Meniere's attacks. This current investigation in Mongolian gerbils

  15. Removing Malmquist bias from linear regressions

    Science.gov (United States)

    Verter, Frances

    1993-01-01

    Malmquist bias is present in all astronomical surveys where sources are observed above an apparent brightness threshold. Those sources which can be detected at progressively larger distances are progressively more limited to the intrinsically luminous portion of the true distribution. This bias does not distort any of the measurements, but distorts the sample composition. We have developed the first treatment to correct for Malmquist bias in linear regressions of astronomical data. A demonstration of the corrected linear regression that is computed in four steps is presented.

  16. Conversational flow promotes solidarity.

    Science.gov (United States)

    Koudenburg, Namkje; Postmes, Tom; Gordijn, Ernestine H

    2013-01-01

    Social interaction is fundamental to the development of various aspects of "we-ness". Previous research has focused on the role the content of interaction plays in establishing feelings of unity, belongingness and shared reality (a cluster of variables referred to as solidarity here). The present paper is less concerned with content, but focuses on the form of social interaction. We propose that the degree to which conversations flow smoothly or not is, of itself, a cue to solidarity. We test this hypothesis in samples of unacquainted and acquainted dyads who communicate via headsets. Conversational flow is disrupted by introducing a delay in the auditory feedback (vs. no delay). Results of three studies show that smoothly coordinated conversations (compared with disrupted conversations and a control condition) increase feelings of belonging and perceptions of group entitativity, independently of conversation content. These effects are driven by the subjective experience of conversational flow. Our data suggest that this process occurs largely beyond individuals' control. We conclude that the form of social interaction is a powerful cue for inferring group solidarity. Implications for the impact of modern communication technology on developing a shared social identity are discussed.

  17. Conversational flow promotes solidarity.

    Directory of Open Access Journals (Sweden)

    Namkje Koudenburg

    Full Text Available Social interaction is fundamental to the development of various aspects of "we-ness". Previous research has focused on the role the content of interaction plays in establishing feelings of unity, belongingness and shared reality (a cluster of variables referred to as solidarity here. The present paper is less concerned with content, but focuses on the form of social interaction. We propose that the degree to which conversations flow smoothly or not is, of itself, a cue to solidarity. We test this hypothesis in samples of unacquainted and acquainted dyads who communicate via headsets. Conversational flow is disrupted by introducing a delay in the auditory feedback (vs. no delay. Results of three studies show that smoothly coordinated conversations (compared with disrupted conversations and a control condition increase feelings of belonging and perceptions of group entitativity, independently of conversation content. These effects are driven by the subjective experience of conversational flow. Our data suggest that this process occurs largely beyond individuals' control. We conclude that the form of social interaction is a powerful cue for inferring group solidarity. Implications for the impact of modern communication technology on developing a shared social identity are discussed.

  18. A thermalization energy analysis of the threshold voltage shift in amorphous indium gallium zinc oxide thin film transistors under positive gate bias stress

    Energy Technology Data Exchange (ETDEWEB)

    Niang, K. M.; Flewitt, A. J., E-mail: ajf@eng.cam.ac.uk [Electrical Engineering Division, Cambridge University, J J Thomson Avenue, Cambridge CB3 0FA (United Kingdom); Barquinha, P. M. C.; Martins, R. F. P. [i3N/CENIMAT, Department of Materials Science, Faculty of Science and Technology, Universidade NOVA de Lisboa and CEMOP/UNINOVA, Campus de Caparica, 2829-516 Caparica (Portugal); Cobb, B. [Holst Centre/TNO, High Tech Campus 31, 5656AE Eindhoven (Netherlands); Powell, M. J. [252, Valley Drive, Kendal LA9 7SL (United Kingdom)

    2016-02-29

    Thin film transistors (TFTs) employing an amorphous indium gallium zinc oxide (a-IGZO) channel layer exhibit a positive shift in the threshold voltage under the application of positive gate bias stress (PBS). The time and temperature dependence of the threshold voltage shift was measured and analysed using the thermalization energy concept. The peak energy barrier to defect conversion is extracted to be 0.75 eV and the attempt-to-escape frequency is extracted to be 10{sup 7} s{sup −1}. These values are in remarkable agreement with measurements in a-IGZO TFTs under negative gate bias illumination stress (NBIS) reported recently (Flewitt and Powell, J. Appl. Phys. 115, 134501 (2014)). This suggests that the same physical process is responsible for both PBS and NBIS, and supports the oxygen vacancy defect migration model that the authors have previously proposed.

  19. Nuclear spin conversion in formaldehyde

    OpenAIRE

    Chapovsky, Pavel L.

    2000-01-01

    Theoretical model of the nuclear spin conversion in formaldehyde (H2CO) has been developed. The conversion is governed by the intramolecular spin-rotation mixing of molecular ortho and para states. The rate of conversion has been found equal 1.4*10^{-4}~1/s*Torr. Temperature dependence of the spin conversion has been predicted to be weak in the wide temperature range T=200-900 K.

  20. Mapping species distributions with MAXENT using a geographically biased sample of presence data: a performance assessment of methods for correcting sampling bias.

    Science.gov (United States)

    Fourcade, Yoan; Engler, Jan O; Rödder, Dennis; Secondi, Jean

    2014-01-01

    MAXENT is now a common species distribution modeling (SDM) tool used by conservation practitioners for predicting the distribution of a species from a set of records and environmental predictors. However, datasets of species occurrence used to train the model are often biased in the geographical space because of unequal sampling effort across the study area. This bias may be a source of strong inaccuracy in the resulting model and could lead to incorrect predictions. Although a number of sampling bias correction methods have been proposed, there is no consensual guideline to account for it. We compared here the performance of five methods of bias correction on three datasets of species occurrence: one "virtual" derived from a land cover map, and two actual datasets for a turtle (Chrysemys picta) and a salamander (Plethodon cylindraceus). We subjected these datasets to four types of sampling biases corresponding to potential types of empirical biases. We applied five correction methods to the biased samples and compared the outputs of distribution models to unbiased datasets to assess the overall correction performance of each method. The results revealed that the ability of methods to correct the initial sampling bias varied greatly depending on bias type, bias intensity and species. However, the simple systematic sampling of records consistently ranked among the best performing across the range of conditions tested, whereas other methods performed more poorly in most cases. The strong effect of initial conditions on correction performance highlights the need for further research to develop a step-by-step guideline to account for sampling bias. However, this method seems to be the most efficient in correcting sampling bias and should be advised in most cases.

  1. On the relative independence of thinking biases and cognitive ability.

    Science.gov (United States)

    Stanovich, Keith E; West, Richard F

    2008-04-01

    In 7 different studies, the authors observed that a large number of thinking biases are uncorrelated with cognitive ability. These thinking biases include some of the most classic and well-studied biases in the heuristics and biases literature, including the conjunction effect, framing effects, anchoring effects, outcome bias, base-rate neglect, "less is more" effects, affect biases, omission bias, myside bias, sunk-cost effect, and certainty effects that violate the axioms of expected utility theory. In a further experiment, the authors nonetheless showed that cognitive ability does correlate with the tendency to avoid some rational thinking biases, specifically the tendency to display denominator neglect, probability matching rather than maximizing, belief bias, and matching bias on the 4-card selection task. The authors present a framework for predicting when cognitive ability will and will not correlate with a rational thinking tendency. (c) 2008 APA, all rights reserved.

  2. Assessing the extent of non-stationary biases in GCMs

    Science.gov (United States)

    Nahar, Jannatun; Johnson, Fiona; Sharma, Ashish

    2017-06-01

    General circulation models (GCMs) are the main tools for estimating changes in the climate for the future. The imperfect representation of climate models introduces biases in the simulations that need to be corrected prior to their use for impact assessments. Bias correction methods generally assume that the bias calculated over the historical period does not change and can be applied to the future. This study investigates this assumption by considering the extent and nature of bias non-stationarity using 20th century precipitation and temperature simulations from six CMIP5 GCMs across Australia. Four statistics (mean, standard deviation, 10th and 90th quantiles) in monthly and seasonal biases are obtained for three different time window lengths (10, 25 and 33 years) to examine the properties of bias over time. This approach is repeated for two different phases of the Interdecadal Pacific Oscillation (IPO), which is known to have strong influences on the Australian climate. It is found that bias non-stationarity at decadal timescales is indeed an issue over some of Australia for some GCMs. When considering interdecadal variability there are significant difference in the bias between positive and negative phases of the IPO. Regional analyses confirmed these findings with the largest differences seen on the east coast of Australia, where IPO impacts tend to be the strongest. The nature of the bias non-stationarity found in this study suggests that it will be difficult to modify existing bias correction approaches to account for non-stationary biases. A more practical approach for impact assessments that use bias correction maybe to use a selection of GCMs where the assumption of bias non-stationarity holds.

  3. Effects of Bias Modification Training in Binge Eating Disorder.

    Science.gov (United States)

    Schmitz, Florian; Svaldi, Jennifer

    2017-09-01

    Food-related attentional biases have been identified as maintaining factors in binge eating disorder (BED) as they can trigger a binge episode. Bias modification training may reduce symptoms, as it has been shown to be successful in other appetitive disorders. The aim of this study was to assess and modify food-related biases in BED. It was tested whether biases could be increased and decreased by means of a modified dot-probe paradigm, how long such bias modification persisted, and whether this affected subjective food craving. Participants were randomly assigned to a bias enhancement (attend to food stimulus) group or to a bias reduction (avoid food stimulus) group. Food-related attentional bias was found to be successfully reduced in the bias-reduction group, and effects persisted briefly. Additionally, subjective craving for food was influenced by the intervention, and possible mechanisms are discussed. Given these promising initial results, future research should investigate boundary conditions of the experimental intervention to understand how it could complement treatment of BED. Copyright © 2017. Published by Elsevier Ltd.

  4. Gene conversion in the rice genome

    DEFF Research Database (Denmark)

    Xu, Shuqing; Clark, Terry; Zheng, Hongkun

    2008-01-01

    -chromosomal conversions distributed between chromosome 1 and 5, 2 and 6, and 3 and 5 are more frequent than genome average (Z-test, P ... is not tightly linked to natural selection in the rice genome. To assess the contribution of segmental duplication on gene conversion statistics, we determined locations of conversion partners with respect to inter-chromosomal segment duplication. The number of conversions associated with segmentation is less...... involved in conversion events. CONCLUSION: The evolution of gene families in the rice genome may have been accelerated by conversion with pseudogenes. Our analysis suggests a possible role for gene conversion in the evolution of pathogen-response genes....

  5. Attentional bias in math anxiety.

    Science.gov (United States)

    Rubinsten, Orly; Eidlin, Hili; Wohl, Hadas; Akibli, Orly

    2015-01-01

    Cognitive theory from the field of general anxiety suggests that the tendency to display attentional bias toward negative information results in anxiety. Accordingly, the current study aims to investigate whether attentional bias is involved in math anxiety (MA) as well (i.e., a persistent negative reaction to math). Twenty seven participants (14 with high levels of MA and 13 with low levels of MA) were presented with a novel computerized numerical version of the well established dot probe task. One of six types of prime stimuli, either math related or typically neutral, was presented on one side of a computer screen. The prime was preceded by a probe (either one or two asterisks) that appeared in either the prime or the opposite location. Participants had to discriminate probe identity (one or two asterisks). Math anxious individuals reacted faster when the probe was at the location of the numerical related stimuli. This suggests the existence of attentional bias in MA. That is, for math anxious individuals, the cognitive system selectively favored the processing of emotionally negative information (i.e., math related words). These findings suggest that attentional bias is linked to unduly intense MA symptoms.

  6. A retrieval-based approach to eliminating hindsight bias.

    Science.gov (United States)

    Van Boekel, Martin; Varma, Keisha; Varma, Sashank

    2017-03-01

    Individuals exhibit hindsight bias when they are unable to recall their original responses to novel questions after correct answers are provided to them. Prior studies have eliminated hindsight bias by modifying the conditions under which original judgments or correct answers are encoded. Here, we explored whether hindsight bias can be eliminated by manipulating the conditions that hold at retrieval. Our retrieval-based approach predicts that if the conditions at retrieval enable sufficient discrimination of memory representations of original judgments from memory representations of correct answers, then hindsight bias will be reduced or eliminated. Experiment 1 used the standard memory design to replicate the hindsight bias effect in middle-school students. Experiments 2 and 3 modified the retrieval phase of this design, instructing participants beforehand that they would be recalling both their original judgments and the correct answers. As predicted, this enabled participants to form compound retrieval cues that discriminated original judgment traces from correct answer traces, and eliminated hindsight bias. Experiment 4 found that when participants were not instructed beforehand that they would be making both recalls, they did not form discriminating retrieval cues, and hindsight bias returned. These experiments delineate the retrieval conditions that produce-and fail to produce-hindsight bias.

  7. Large-scale assembly bias of dark matter halos

    Energy Technology Data Exchange (ETDEWEB)

    Lazeyras, Titouan; Musso, Marcello; Schmidt, Fabian, E-mail: titouan@mpa-garching.mpg.de, E-mail: mmusso@sas.upenn.edu, E-mail: fabians@mpa-garching.mpg.de [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85748 Garching (Germany)

    2017-03-01

    We present precise measurements of the assembly bias of dark matter halos, i.e. the dependence of halo bias on other properties than the mass, using curved 'separate universe' N-body simulations which effectively incorporate an infinite-wavelength matter overdensity into the background density. This method measures the LIMD (local-in-matter-density) bias parameters b {sub n} in the large-scale limit. We focus on the dependence of the first two Eulerian biases b {sup E} {sup {sub 1}} and b {sup E} {sup {sub 2}} on four halo properties: the concentration, spin, mass accretion rate, and ellipticity. We quantitatively compare our results with previous works in which assembly bias was measured on fairly small scales. Despite this difference, our findings are in good agreement with previous results. We also look at the joint dependence of bias on two halo properties in addition to the mass. Finally, using the excursion set peaks model, we attempt to shed new insights on how assembly bias arises in this analytical model.

  8. Effects of Inventory Bias on Landslide Susceptibility Calculations

    Science.gov (United States)

    Stanley, T. A.; Kirschbaum, D. B.

    2017-01-01

    Many landslide inventories are known to be biased, especially inventories for large regions such as Oregon's SLIDO or NASA's Global Landslide Catalog. These biases must affect the results of empirically derived susceptibility models to some degree. We evaluated the strength of the susceptibility model distortion from postulated biases by truncating an unbiased inventory. We generated a synthetic inventory from an existing landslide susceptibility map of Oregon, then removed landslides from this inventory to simulate the effects of reporting biases likely to affect inventories in this region, namely population and infrastructure effects. Logistic regression models were fitted to the modified inventories. Then the process of biasing a susceptibility model was repeated with SLIDO data. We evaluated each susceptibility model with qualitative and quantitative methods. Results suggest that the effects of landslide inventory bias on empirical models should not be ignored, even if those models are, in some cases, useful. We suggest fitting models in well-documented areas and extrapolating across the study region as a possible approach to modeling landslide susceptibility with heavily biased inventories.

  9. Dual-electrode biasing experiments in KT-5C device

    International Nuclear Information System (INIS)

    Yu Yi; Lu Ronghua; Wang Chen; Pan Geshen; Wen Yizhi; Yu Changxuan; Ma Jinxiu; Wan Shude; Liu Wandong

    2005-01-01

    Based on the single biasing electrode experiments to optimize the confinement of plasma in the device of KT-5C tokamak, dual-biasing electrodes were inserted into the KT5C plasma for the first time to explore the enhancement of the effects of biasing and the mechanisms of the biasing. By means of applying different combinations of biasing voltages to the dual electrodes, the changes in E r , which is the key factor for boosting up the Er x B flow shear, were observed. The time evolution showed the inner electrode played a major role in dual-biasing, for it always drew a larger current than the outer one. The outer electrode made little influence. It turned out that the dual-biasing electrodes were as effective as a single one, in improving plasma confinement, for the mechanism of biasing was essentially an edge effect. (author)

  10. Bias-Correction in Vector Autoregressive Models: A Simulation Study

    Directory of Open Access Journals (Sweden)

    Tom Engsted

    2014-03-01

    Full Text Available We analyze the properties of various methods for bias-correcting parameter estimates in both stationary and non-stationary vector autoregressive models. First, we show that two analytical bias formulas from the existing literature are in fact identical. Next, based on a detailed simulation study, we show that when the model is stationary this simple bias formula compares very favorably to bootstrap bias-correction, both in terms of bias and mean squared error. In non-stationary models, the analytical bias formula performs noticeably worse than bootstrapping. Both methods yield a notable improvement over ordinary least squares. We pay special attention to the risk of pushing an otherwise stationary model into the non-stationary region of the parameter space when correcting for bias. Finally, we consider a recently proposed reduced-bias weighted least squares estimator, and we find that it compares very favorably in non-stationary models.

  11. Biased lineups: sequential presentation reduces the problem.

    Science.gov (United States)

    Lindsay, R C; Lea, J A; Nosworthy, G J; Fulford, J A; Hector, J; LeVan, V; Seabrook, C

    1991-12-01

    Biased lineups have been shown to increase significantly false, but not correct, identification rates (Lindsay, Wallbridge, & Drennan, 1987; Lindsay & Wells, 1980; Malpass & Devine, 1981). Lindsay and Wells (1985) found that sequential lineup presentation reduced false identification rates, presumably by reducing reliance on relative judgment processes. Five staged-crime experiments were conducted to examine the effect of lineup biases and sequential presentation on eyewitness recognition accuracy. Sequential lineup presentation significantly reduced false identification rates from fair lineups as well as from lineups biased with regard to foil similarity, instructions, or witness attire, and from lineups biased in all of these ways. The results support recommendations that police present lineups sequentially.

  12. Conversation after Right Hemisphere Brain Damage: Motivations for Applying Conversation Analysis

    Science.gov (United States)

    Barnes, Scott; Armstrong, Elizabeth

    2010-01-01

    Despite the well documented pragmatic deficits that can arise subsequent to Right Hemisphere Brain Damage (RHBD), few researchers have directly studied everyday conversations involving people with RHBD. In recent years, researchers have begun applying Conversation Analysis (CA) to the everyday talk of people with aphasia. This research programme…

  13. Students' gender bias in teaching evaluations

    Directory of Open Access Journals (Sweden)

    Narissra Punyanunt-Carter

    2015-09-01

    Full Text Available The goal of this study was to investigate if there is gender bias in student evaluations. Researchers administered a modified version of the teacher evaluation forms to 58 students (male=30; female=28 in a basic introductory communications class. Half the class was instructed to fill out the survey about a male professor, and the other half a female professor. Researchers broke down the evaluation results question by question in order to give a detailed account of the findings. Results revealed that there is certainly some gender bias at work when students evaluate their instructors. It was also found that gender bias does not significantly affect the evaluations. The results align with other findings in the available literature, which point to some sort of pattern regarding gender bias in evaluations, but it still seems to be inconsequential.  DOI: 10.18870/hlrc.v5i3.234

  14. Simulation of HPIB propagation in biased charge collector

    International Nuclear Information System (INIS)

    Li Hongyu; Qiu Aici

    2004-01-01

    A 2.5D PIC simulation using KARAT code for inner charge propagation within biased charge collector for measuring HPIB is presented. The simulation results indicate that the charges were neutralized but the current non-neutralized in the biased charge collector. The influence of ions collected vs biased voltage of the collector was also simulated. -800 V biased voltage can meet the measurement of 500 keV HPIB, and this is consistent with the experimental results

  15. DIRECT ENERGY CONVERSION (DEC) FISSION REACTORS - A U.S. NERI PROJECT

    International Nuclear Information System (INIS)

    Beller, D.; Polansky, G.

    2000-01-01

    The direct conversion of the electrical energy of charged fission fragments was examined early in the nuclear reactor era, and the first theoretical treatment appeared in the literature in 1957. Most of the experiments conducted during the next ten years to investigate fission fragment direct energy conversion (DEC) were for understanding the nature and control of the charged particles. These experiments verified fundamental physics and identified a number of specific problem areas, but also demonstrated a number of technical challenges that limited DEC performance. Because DEC was insufficient for practical applications, by the late 1960s most R and D ceased in the US. Sporadic interest in the concept appears in the literature until this day, but there have been no recent programs to develop the technology. This has changed with the Nuclear Energy Research Initiative that was funded by the U.S. Congress in 1999. Most of the previous concepts were based on a fission electric cell known as a triode, where a central cathode is coated with a thin layer of nuclear fuel. A fission fragment that leaves the cathode with high kinetic energy and a large positive charge is decelerated as it approaches the anode by a charge differential of several million volts, it then deposits its charge in the anode after its kinetic energy is exhausted. Large numbers of low energy electrons leave the cathode with each fission fragment; they are suppressed by negatively biased on grid wires or by magnetic fields. Other concepts include magnetic collimators and quasi-direct magnetohydrodynamic generation (steady flow or pulsed). We present the basic principles of DEC fission reactors, review the previous research, discuss problem areas in detail and identify technological developments of the last 30 years relevant to overcoming these obstacles. A prognosis for future development of direct energy conversion fission reactors will be presented

  16. New Trends in Magnetic Exchange Bias

    Science.gov (United States)

    Mougin, Alexandra; Mangin, Stéphane; Bobo, Jean-Francois; Loidl, Alois

    2005-05-01

    The study of layered magnetic structures is one of the hottest topics in magnetism due to the growing attraction of applications in magnetic sensors and magnetic storage media, such as random access memory. For almost half a century, new discoveries have driven researchers to re-investigate magnetism in thin film structures. Phenomena such as giant magnetoresistance, tunneling magnetoresistance, exchange bias and interlayer exchange coupling led to new ideas to construct devices, based not only on semiconductors but on a variety of magnetic materials Upon cooling fine cobalt particles in a magnetic field through the Néel temperature of their outer antiferromagnetic oxide layer, Meiklejohn and Bean discovered exchange bias in 1956. The exchange bias effect through which an antiferromagnetic AF layer can cause an adjacent ferromagnetic F layer to develop a preferred direction of magnetization, is widely used in magnetoelectronics technology to pin the magnetization of a device reference layer in a desired direction. However, the origin and effects due to exchange interaction across the interface between antiferromagneic and ferromagnetic layers are still debated after about fifty years of research, due to the extreme difficulty associated with the determination of the magnetic interfacial structure in F/AF bilayers. Indeed, in an AF/F bilayer system, the AF layer acts as “the invisible man” during conventional magnetic measurements and the presence of the exchange coupling is evidenced indirectly through the unusual behavior of the adjacent F layer. Basically, the coercive field of the F layer increases in contact with the AF and, in some cases, its hysteresis loop is shifted by an amount called exchange bias field. Thus, AF/F exchange coupling generates a new source of anisotropy in the F layer. This induced anisotropy strongly depends on basic features such as the magnetocrystalline anisotropy, crystallographic and spin structures, defects, domain patterns etc

  17. La conversion de Paul, regards croisés Paul’s conversion. Cross perspectives

    Directory of Open Access Journals (Sweden)

    Elian Cuvillier

    2009-09-01

    Full Text Available Au plan historique, les traditions relatives à la conversion de Paul, chutant de son cheval sur le chemin de Damas, confrontent l’exégète à trois problèmes importants : y avait-il un cheval, cela se passait-il sur le chemin de Damas et était-ce bien une conversion ? Entendues avec l’humour et la distance critique nécessaires, ces trois questions constituent les trois chapitres de cet article. Le premier « Y avait-il un cheval ? » s’intéresse à l’histoire de la réception de l’épisode de la conversion de Paul, en particulier dans la peinture et la littérature. Le second « Cela se passait-il sur le chemin de Damas ? » est consacrée au récit que l’auteur du livre des Actes propose de la conversion de Paul, récit qui constitue, bien souvent, la porte d’entrée exclusive pour aborder le thème. Le troisième « Etait-ce bien une conversion ? » analyse les témoignages de l’apôtre lui-même à travers deux passages clés de ses épîtres authentiques.Historically speaking, the traditions concerning the conversion of Paul, falling from his horse on the road to Damascus, confront the exegete with three important problems : was there a horse, did it happen on the road to Damacus and was it really a conversion ? These three questions, considered with humor and critical distance, constitute the three sections of this article. The first part « Was there a horse ? » considers the history of the reception of the episode of the conversion of Paul, particularly in art and literature. The second one « Did it happen on the road to Damascus ? » is devoted to the story of the conversion of Paul proposed by the author of the book of Acts, which is very often the exclusive entrance to the discussion of this theme. The third section « Was it really a conversion ? » analyzes the account given by the apostle himself in two key passages of his authentic epistles.

  18. Implementation of linear bias corrections for calorimeters at Mound

    International Nuclear Information System (INIS)

    Barnett, T.M.

    1993-01-01

    In the past, Mound has generally made relative bias corrections as part of the calibration of individual calorimeters. The correction made was the same over the entire operating range of the calorimeter, regardless of the magnitude of the range. Recently, an investigation was performed to check the relevancy of using linear bias corrections to calibrate the calorimeters. The bias is obtained by measuring calibrated plutonium and/or electrical heat standards over the operating range of the calorimeter. The bias correction is then calculated using a simple least squares fit (y = mx + b) of the bias in milliwatts over the operating range of the calorimeter in watts. The equation used is B i = B 0 + (B w * W m ), where B i is the bias at any given power in milliwatts, B 0 is the intercept (absolute bias in milliwatts), B w is the slope (relative bias in milliwatts per watt), and W m is the measured power in watts. The results of the study showed a decrease in the random error of bias corrected data for most of the calorimeters which are operated over a large wattage range (greater than an order of magnitude). The linear technique for bias correction has been fully implemented at Mound and has been included in the Technical Manual, ''A Measurement Control Program for Radiometric Calorimeters at Mound'' (MD-21900)

  19. Conversational Agents in E-Learning

    Science.gov (United States)

    Kerry, Alice; Ellis, Richard; Bull, Susan

    This paper discusses the use of natural language or 'conversational' agents in e-learning environments. We describe and contrast the various applications of conversational agent technology represented in the e-learning literature, including tutors, learning companions, language practice and systems to encourage reflection. We offer two more detailed examples of conversational agents, one which provides learning support, and the other support for self-assessment. Issues and challenges for developers of conversational agent systems for e-learning are identified and discussed.

  20. Revealing the Cosmic Web-dependent Halo Bias

    Science.gov (United States)

    Yang, Xiaohu; Zhang, Youcai; Lu, Tianhuan; Wang, Huiyuan; Shi, Feng; Tweed, Dylan; Li, Shijie; Luo, Wentao; Lu, Yi; Yang, Lei

    2017-10-01

    Halo bias is the one of the key ingredients of the halo models. It was shown at a given redshift to be only dependent, to the first order, on the halo mass. In this study, four types of cosmic web environments—clusters, filaments, sheets, and voids—are defined within a state-of-the-art high-resolution N-body simulation. Within these environments, we use both halo-dark matter cross correlation and halo-halo autocorrelation functions to probe the clustering properties of halos. The nature of the halo bias differs strongly between the four different cosmic web environments described here. With respect to the overall population, halos in clusters have significantly lower biases in the {10}11.0˜ {10}13.5 {h}-1 {M}⊙ mass range. In other environments, however, halos show extremely enhanced biases up to a factor 10 in voids for halos of mass ˜ {10}12.0 {h}-1 {M}⊙ . Such a strong cosmic web environment dependence in the halo bias may play an important role in future cosmological and galaxy formation studies. Within this cosmic web framework, the age dependency of halo bias is found to be only significant in clusters and filaments for relatively small halos ≲ {10}12.5 {h}-1 {M}⊙ .

  1. Boiler conversions for biomass

    Energy Technology Data Exchange (ETDEWEB)

    Kinni, J [Tampella Power Inc., Tampere (Finland)

    1997-12-31

    Boiler conversions from grate- and oil-fired boilers to bubbling fluidized bed combustion have been most common in pulp and paper industry. Water treatment sludge combustion, need for additional capacity and tightened emission limits have been the driving forces for the conversion. To accomplish a boiler conversion for biofuel, the lower part of the boiler is replaced with a fluidized bed bottom and new fuel, ash and air systems are added. The Imatran Voima Rauhalahti pulverized-peat-fired boiler was converted to bubbling fluidized bed firing in 1993. In the conversion the boiler capacity was increased by 10 % to 295 MWth and NO{sub x} emissions dropped. In the Kymmene Kuusankoski boiler, the reason for conversion was the combustion of high chlorine content biosludge. The emissions have been under general European limits. During the next years, the emission limits will tighten and the boilers will be designed for most complete combustion and compounds, which can be removed from flue gases, will be taken care of after the boiler. (orig.) 3 refs.

  2. Boiler conversions for biomass

    Energy Technology Data Exchange (ETDEWEB)

    Kinni, J. [Tampella Power Inc., Tampere (Finland)

    1996-12-31

    Boiler conversions from grate- and oil-fired boilers to bubbling fluidized bed combustion have been most common in pulp and paper industry. Water treatment sludge combustion, need for additional capacity and tightened emission limits have been the driving forces for the conversion. To accomplish a boiler conversion for biofuel, the lower part of the boiler is replaced with a fluidized bed bottom and new fuel, ash and air systems are added. The Imatran Voima Rauhalahti pulverized-peat-fired boiler was converted to bubbling fluidized bed firing in 1993. In the conversion the boiler capacity was increased by 10 % to 295 MWth and NO{sub x} emissions dropped. In the Kymmene Kuusankoski boiler, the reason for conversion was the combustion of high chlorine content biosludge. The emissions have been under general European limits. During the next years, the emission limits will tighten and the boilers will be designed for most complete combustion and compounds, which can be removed from flue gases, will be taken care of after the boiler. (orig.) 3 refs.

  3. Dwalingen in de methodologie. II. Bias door vragenlijsten

    DEFF Research Database (Denmark)

    Pouwer, F; Van Der Ploeg, Henk M; Bramsen, I

    1998-01-01

    Some characteristics of self-report questionnaires can result in bias in responding. When a test item or a questionnaire is biased, the observed scores form an imprecise measurement of reality as a consequence of systematic errors of measurement. Causes of such bias are: unclear instructions, vague...

  4. Non-Gaussian bias: insights from discrete density peaks

    CERN Document Server

    Desjacques, Vincent; Riotto, Antonio

    2013-01-01

    Corrections induced by primordial non-Gaussianity to the linear halo bias can be computed from a peak-background split or the widespread local bias model. However, numerical simulations clearly support the prediction of the former, in which the non-Gaussian amplitude is proportional to the linear halo bias. To understand better the reasons behind the failure of standard Lagrangian local bias, in which the halo overdensity is a function of the local mass overdensity only, we explore the effect of a primordial bispectrum on the 2-point correlation of discrete density peaks. We show that the effective local bias expansion to peak clustering vastly simplifies the calculation. We generalize this approach to excursion set peaks and demonstrate that the resulting non-Gaussian amplitude, which is a weighted sum of quadratic bias factors, precisely agrees with the peak-background split expectation, which is a logarithmic derivative of the halo mass function with respect to the normalisation amplitude. We point out tha...

  5. Recognizing and reducing cognitive bias in clinical and forensic neurology.

    Science.gov (United States)

    Satya-Murti, Saty; Lockhart, Joseph

    2015-10-01

    In medicine, cognitive errors form the basis of bias in clinical practice. Several types of bias are common and pervasive, and may lead to inaccurate diagnosis or treatment. Forensic and clinical neurology, even when aided by current technologies, are still dependent on cognitive interpretations, and therefore prone to bias. This article discusses 4 common biases that can lead the clinician astray. They are confirmation bias (selective gathering of and neglect of contradictory evidence); base rate bias (ignoring or misusing prevailing base rate data); hindsight bias (oversimplification of past causation); and good old days bias (the tendency for patients to misremember and exaggerate their preinjury functioning). We briefly describe strategies adopted from the field of psychology that could minimize bias. While debiasing is not easy, reducing such errors requires awareness and acknowledgment of our susceptibility to these cognitive distortions.

  6. Attentional Bias in Math Anxiety

    Directory of Open Access Journals (Sweden)

    Orly eRubinsten

    2015-10-01

    Full Text Available Cognitive theory from the field of general anxiety suggests that the tendency to display attentional bias toward negative information results in anxiety. Accordingly, the current study aims to investigate whether attentional bias is involved in math anxiety as well (i.e., a persistent negative reaction to math. Twenty seven participants (14 with high levels of math anxiety and 13 with low levels of math anxiety were presented with a novel computerized numerical version of the well established dot probe task. One of 6 types of prime stimuli, either math related or typically neutral, were presented on one side of a computer screen. The prime was preceded by a probe (either one or two asterisks that appeared in either the prime or the opposite location. Participants had to discriminate probe identity (one or two asterisks. Math anxious individuals reacted faster when the probe was at the location of the numerical related stimuli. This suggests the existence of attentional bias in math anxiety. That is, for math anxious individuals, the cognitive system selectively favored the processing of emotionally negative information (i.e., math related words. These findings suggest that attentional bias is linked to unduly intense math anxiety symptoms.

  7. Exchange bias in nearly perpendicularly coupled ferromagnetic/ferromagnetic system

    International Nuclear Information System (INIS)

    Bu, K.M.; Kwon, H.Y.; Oh, S.W.; Won, C.

    2012-01-01

    Exchange bias phenomena appear not only in ferromagnetic/antiferromagnetic systems but also in ferromagnetic/ferromagnetic systems in which two layers are nearly perpendicularly coupled. We investigated the origin of the symmetry-breaking mechanism and the relationship between the exchange bias and the system's energy parameters. We compared the results of computational Monte Carlo simulations with those of theoretical model calculation. We found that the exchange bias exhibited nonlinear behaviors, including sign reversal and singularities. These complicated behaviors were caused by two distinct magnetization processes depending on the interlayer coupling strength. The exchange bias reached a maximum at the transition between the two magnetization processes. - Highlights: ► Exchange bias phenomena are found in perpendicularly coupled F/F systems. ► Exchange bias exhibits nonlinear behaviors, including sign reversal and singularities. ► These complicated behaviors were caused by two distinct magnetization processes. ► Exchange bias reached a maximum at the transition between the two magnetization processes. ► We established an equation to maximize the exchange bias in perpendicularly coupled F/F system.

  8. Blind signal processing algorithms under DC biased Gaussian noise

    Science.gov (United States)

    Kim, Namyong; Byun, Hyung-Gi; Lim, Jeong-Ok

    2013-05-01

    Distortions caused by the DC-biased laser input can be modeled as DC biased Gaussian noise and removing DC bias is important in the demodulation process of the electrical signal in most optical communications. In this paper, a new performance criterion and a related algorithm for unsupervised equalization are proposed for communication systems in the environment of channel distortions and DC biased Gaussian noise. The proposed criterion utilizes the Euclidean distance between the Dirac-delta function located at zero on the error axis and a probability density function of biased constant modulus errors, where constant modulus error is defined by the difference between the system out and a constant modulus calculated from the transmitted symbol points. From the results obtained from the simulation under channel models with fading and DC bias noise abruptly added to background Gaussian noise, the proposed algorithm converges rapidly even after the interruption of DC bias proving that the proposed criterion can be effectively applied to optical communication systems corrupted by channel distortions and DC bias noise.

  9. Solar energy conversion systems

    CERN Document Server

    Brownson, Jeffrey R S

    2013-01-01

    Solar energy conversion requires a different mind-set from traditional energy engineering in order to assess distribution, scales of use, systems design, predictive economic models for fluctuating solar resources, and planning to address transient cycles and social adoption. Solar Energy Conversion Systems examines solar energy conversion as an integrative design process, applying systems thinking methods to a solid knowledge base for creators of solar energy systems. This approach permits different levels of access for the emerging broad audience of scientists, engineers, architects, planners

  10. Bias-correction in vector autoregressive models: A simulation study

    DEFF Research Database (Denmark)

    Engsted, Tom; Pedersen, Thomas Quistgaard

    We analyze and compare the properties of various methods for bias-correcting parameter estimates in vector autoregressions. First, we show that two analytical bias formulas from the existing literature are in fact identical. Next, based on a detailed simulation study, we show that this simple...... and easy-to-use analytical bias formula compares very favorably to the more standard but also more computer intensive bootstrap bias-correction method, both in terms of bias and mean squared error. Both methods yield a notable improvement over both OLS and a recently proposed WLS estimator. We also...... of pushing an otherwise stationary model into the non-stationary region of the parameter space during the process of correcting for bias....

  11. Publication bias in dermatology systematic reviews and meta-analyses.

    Science.gov (United States)

    Atakpo, Paul; Vassar, Matt

    2016-05-01

    Systematic reviews and meta-analyses in dermatology provide high-level evidence for clinicians and policy makers that influence clinical decision making and treatment guidelines. One methodological problem with systematic reviews is the under representation of unpublished studies. This problem is due in part to publication bias. Omission of statistically non-significant data from meta-analyses may result in overestimation of treatment effect sizes which may lead to clinical consequences. Our goal was to assess whether systematic reviewers in dermatology evaluate and report publication bias. Further, we wanted to conduct our own evaluation of publication bias on meta-analyses that failed to do so. Our study considered systematic reviews and meta-analyses from ten dermatology journals from 2006 to 2016. A PubMed search was conducted, and all full-text articles that met our inclusion criteria were retrieved and coded by the primary author. 293 articles were included in our analysis. Additionally, we formally evaluated publication bias in meta-analyses that failed to do so using trim and fill and cumulative meta-analysis by precision methods. Publication bias was mentioned in 107 articles (36.5%) and was formally evaluated in 64 articles (21.8%). Visual inspection of a funnel plot was the most common method of evaluating publication bias. Publication bias was present in 45 articles (15.3%), not present in 57 articles (19.5%) and not determined in 191 articles (65.2%). Using the trim and fill method, 7 meta-analyses (33.33%) showed evidence of publication bias. Although the trim and fill method only found evidence of publication bias in 7 meta-analyses, the cumulative meta-analysis by precision method found evidence of publication bias in 15 meta-analyses (71.4%). Many of the reviews in our study did not mention or evaluate publication bias. Further, of the 42 articles that stated following PRISMA reporting guidelines, 19 (45.2%) evaluated for publication bias. In

  12. Direct conversion of fusion energy

    International Nuclear Information System (INIS)

    Johansson, Markus

    2003-03-01

    Deuterium and tritium are expected to be used as fuel in the first fusion reactors. Energy is released as kinetic energy of ions and neutrons, when deuterium reacts with tritium. One way to convert the kinetic energy to electrical energy, is to let the ions and neutrons hit the reactor wall and convert the heat that is caused by the particle bombardment to electrical energy with ordinary thermal conversion. If the kinetic energy of the ions instead is converted directly to electrical energy, a higher efficiency of the energy conversion is possible. The majority of the fusion energy is released as kinetic energy of neutrons, when deuterium reacts with tritium. Fusion reactions such as the D-D reactions, the D- 3 He reaction and the p- 11 B reaction, where a larger part of the fusion energy becomes kinetic energy of charged particles, appears therefore more suitable for direct conversion. Since they have lower reactivity than the D-T reaction, they need a larger βB 2 0 to give sufficiently high fusion power density. Because of this, the fusion configurations spherical torus (ST) and field-reversed configuration (FRC), where high β values are possible, appear interesting. Rosenbluth and Hinton come to the conclusion that efficient direct conversion isn't possible in closed field line systems and that open geometries, which facilitate direct conversion, provide inadequate confinement for D- 3 He. It is confirmed in this study that it doesn't seem possible to achieve as high direct conversion efficiency in closed systems as in open systems. ST and FRC fusion power plants that utilize direct conversion seem however interesting. Calculations with the help of Maple indicate that the reactor parameters needed for a D-D ST and a D 3 He ST hopefully are possible to achieve. The best energy conversion option for a D-D or D 3 He ST appears to be direct electrodynamic conversion (DEC) together with ordinary thermal conversion or liquid metal MHD conversion (LMMHD). For a D

  13. Direct conversion of fusion energy

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Markus

    2003-03-01

    Deuterium and tritium are expected to be used as fuel in the first fusion reactors. Energy is released as kinetic energy of ions and neutrons, when deuterium reacts with tritium. One way to convert the kinetic energy to electrical energy, is to let the ions and neutrons hit the reactor wall and convert the heat that is caused by the particle bombardment to electrical energy with ordinary thermal conversion. If the kinetic energy of the ions instead is converted directly to electrical energy, a higher efficiency of the energy conversion is possible. The majority of the fusion energy is released as kinetic energy of neutrons, when deuterium reacts with tritium. Fusion reactions such as the D-D reactions, the D-{sup 3}He reaction and the p-{sup 11}B reaction, where a larger part of the fusion energy becomes kinetic energy of charged particles, appears therefore more suitable for direct conversion. Since they have lower reactivity than the D-T reaction, they need a larger {beta}B{sup 2}{sub 0} to give sufficiently high fusion power density. Because of this, the fusion configurations spherical torus (ST) and field-reversed configuration (FRC), where high {beta} values are possible, appear interesting. Rosenbluth and Hinton come to the conclusion that efficient direct conversion isn't possible in closed field line systems and that open geometries, which facilitate direct conversion, provide inadequate confinement for D-{sup 3}He. It is confirmed in this study that it doesn't seem possible to achieve as high direct conversion efficiency in closed systems as in open systems. ST and FRC fusion power plants that utilize direct conversion seem however interesting. Calculations with the help of Maple indicate that the reactor parameters needed for a D-D ST and a D{sub 3} He ST hopefully are possible to achieve. The best energy conversion option for a D-D or D{sub 3} He ST appears to be direct electrodynamic conversion (DEC) together with ordinary thermal conversion

  14. [Neuropsychological assessment in conversion disorder].

    Science.gov (United States)

    Demır, Süleyman; Çelıkel, Feryal Çam; Taycan, Serap Erdoğan; Etıkan, İlker

    2013-01-01

    Conversion disorder is characterized by functional impairment in motor, sensory, or neurovegetative systems that cannot be explained by a general medical condition. Diagnostic systems emphasize the absence of an organic basis for the dysfunction observed in conversion disorder. Nevertheless, there is a growing body of data on the specific functional brain correlates of conversion symptoms, particularly those obtained via neuroimaging and neurophysiological assessment. The present study aimed to determine if there are differences in measures of cognitive functioning between patients with conversion disorder and healthy controls. The hypothesis of the study was that the patients with conversion disorder would have poorer neurocognitive performance than the controls. The patient group included 43 patients diagnosed as conversion disorder and other psychiatric comorbidities according to DSM-IV-TR. Control group 1 included 44 patients diagnosed with similar psychiatric comorbidities, but not conversion diosorder, and control group 2 included 43 healthy individuals. All participants completed a sociodemographic questionnaire and were administered the SCID-I and a neuropsychological test battery of 6 tests, including the Serial Digit Learning Test (SDLT), Auditory Verbal Learning Test (AVLT), Wechsler Memory Scale, Stroop Color Word Interference Test, Benton Judgment of Line Orientation Test (BJLOT), and Cancellation Test. The patient group had significantly poorer performance on the SDLT, AVLT, Stroop Color Word Interference Test, and BJLOT than both control groups. The present findings highlight the differences between the groups in learning and memory, executive and visuospatial functions, and attention, which seemed to be specific to conversion disorder.

  15. Recent Advances in Attention Bias Modification for Substance Addictions

    Directory of Open Access Journals (Sweden)

    Melvyn Weibin Zhang

    2018-04-01

    Full Text Available Research on attentional bias modification has increased since 2014. A recent meta-analysis demonstrates evidence for bias modification for substance disorders, including alcohol and tobacco use disorders. Several pharmacological trials have shown that pharmacological agents can attenuate and modify such attentional bias. The pharmacological trials that have appeared to date have produced mixed results, which has clinical implications. Developments in Internet and mobile technologies have transformed how attention bias modification is currently being achieved. There remains great potential for further research that examines the efficacy of technology-aided attention bias interventions.

  16. Giant exchange bias in MnPd/Co bilayers

    International Nuclear Information System (INIS)

    Nguyen Thanh Nam; Nguyen Phu Thuy; Nguyen Anh Tuan; Nguyen Nguyen Phuoc; Suzuki, Takao

    2007-01-01

    A systematic study of exchange bias in MnPd/Co bilayers has been carried out, where the dependences of exchange bias, unidirectional anisotropy constant and coercivity on the thicknesses of MnPd and Co layers were investigated. A huge unidirectional anisotropy constant, J K =2.5erg/cm 2 was observed, which is in reasonable agreement with the theoretical prediction based on the model by Meiklejohn and Bean. The angular dependences of exchange bias field and coercivity have also been examined showing that both exchange bias and coercivity follow 1/cosα rule

  17. Health risk perception, optimistic bias, and personal satisfaction.

    Science.gov (United States)

    Bränström, Richard; Brandberg, Yvonne

    2010-01-01

    To examine change in risk perception and optimistic bias concerning behavior-linked health threats and environmental health threats between adolescence and young adulthood and how these factors related to personal satisfaction. In 1996 and 2002, 1624 adolescents responded to a mailed questionnaire. Adolescents showed strong positive optimistic bias concerning behaviorlinked risks, and this optimistic bias increased with age. Increase in optimistic bias over time predicted increase in personal satisfaction. The capacity to process and perceive potential threats in a positive manner might be a valuable human ability positively influencing personal satisfaction and well-being.

  18. Some design considerations for perpendicular biased ferrite tuners

    International Nuclear Information System (INIS)

    Enchevich, I.B.; Poirier, R.L.

    1994-10-01

    Recently remarkable progress has been achieved in the development of perpendicular biased ferrite tuned rf resonators for fast cycled synchrotrons. Compared with the broadly used parallel biased rf cavities they provide higher resonator quality factor Q. However when designing perpendicular biased cavities, special attention should be paid to the methods to provide eddy current suppression in the resonator walls, the ferrite nonlinearity influence, the generated heat removal, the fast self resonant frequency control. The prospective of a faster additional biasing system are discussed and conclusions are drawn. (author). 8 refs., 6 figs

  19. Amplification biases: possible differences among deviating gene expressions

    Directory of Open Access Journals (Sweden)

    Piumi Francois

    2008-01-01

    Full Text Available Abstract Background Gene expression profiling has become a tool of choice to study pathological or developmental questions but in most cases the material is scarce and requires sample amplification. Two main procedures have been used: in vitro transcription (IVT and polymerase chain reaction (PCR, the former known as linear and the latter as exponential. Previous reports identified enzymatic pitfalls in PCR and IVT protocols; however the possible differences between the sequences affected by these amplification defaults were only rarely explored. Results Screening a bovine cDNA array dedicated to embryonic stages with embryonic (n = 3 and somatic tissues (n = 2, we proceeded to moderate amplifications starting from 1 μg of total RNA (global PCR or IVT one round. Whatever the tissue, 16% of the probes were involved in deviating gene expressions due to amplification defaults. These distortions were likely due to the molecular features of the affected sequences (position within a gene, GC content, hairpin number but also to the relative abundance of these transcripts within the tissues. These deviating genes mainly encoded housekeeping genes from physiological or cellular processes (70% and constituted 2 subsets which did not overlap (molecular features, signal intensities, gene ID. However, the differential expressions identified between embryonic stages were both reliable (minor intersect with biased expressions and relevant (biologically validated. In addition, the relative expression levels of those genes were biologically similar between amplified and unamplified samples. Conclusion Conversely to the most recent reports which challenged the use of intense amplification procedures on minute amounts of RNA, we chose moderate PCR and IVT amplifications for our gene profiling study. Conclusively, it appeared that systematic biases arose even with moderate amplification procedures, independently of (i the sample used: brain, ovary or embryos, (ii

  20. Development of Heuristic Bias Detection in Elementary School

    Science.gov (United States)

    De Neys, Wim; Feremans, Vicky

    2013-01-01

    Although human reasoning is often biased by intuitive heuristics, recent studies have shown that adults and adolescents detect the biased nature of their judgments. The present study focused on the development of this critical bias sensitivity by examining the detection skills of young children in elementary school. Third and 6th graders were…

  1. Changing the conversation: the influence of emotions on conversational valence and alcohol consumption.

    Science.gov (United States)

    Hendriks, Hanneke; van den Putte, Bas; de Bruijn, Gert-Jan

    2014-10-01

    Health campaign effects may be improved by taking interpersonal communication processes into account. The current study, which employed an experimental, pretest-posttest, randomized exposure design (N = 208), investigated whether the emotions induced by anti-alcohol messages influence conversational valence about alcohol and subsequent persuasion outcomes. The study produced three main findings. First, an increase in the emotion fear induced a negative conversational valence about alcohol. Second, fear was most strongly induced by a disgusting message, whereas a humorous appeal induced the least fear. Third, a negative conversational valence elicited healthier binge drinking attitudes, subjective norms, perceived behavioral control, intentions, and behaviors. Thus, health campaign planners and health researchers should pay special attention to the emotional characteristics of health messages and should focus on inducing a healthy conversational valence.

  2. 3 keys to defeating unconscious bias watch, think, act

    CERN Document Server

    Thiederman, Sondra

    2015-01-01

    Have you ever had a biased thought? If the answer is “yes,” join the club. Everybody has biases and, although that doesn’t make us bad people, it does mean we compromise our ability to get along with people who are different from us. The good news is, there’s a lot we can do to defeat bias. Calling on Dr. Sondra Thiederman’s twenty-five years of experience in the diversity/inclusion field, the book lays out an innovative WATCH, THINK, ACT strategy that each of us can immediately apply to the task. Easy-to-read and filled with anecdotes and activities, 3 Keys shows the reader: • How to WATCH their thoughts, experiences, and actions to identify unconscious biases and target them for extinction. • How to THINK in such a way as to weaken and control our biases. • How to ACT to defeat our biases and cultivate the kind of common ground that we know to be inhospitable to the survival of bias. Designed to motivate real change, the answer to defeating our biases is in these pages. The rest is up to you...

  3. Analysis of microstructural evolution driven by production bias

    International Nuclear Information System (INIS)

    Woo, C.H.; Semenov, A.A.; Singh, B.N.

    1993-01-01

    The concept of production bias was first considered in the preceding workshop in this series at Silkeborg in 1989. Since then, much work has been done to investigate the validity of the concept, and its usefulness in complementing the current theory of microstructure evolution based solely on the sink bias (e.g., dislocation bias) as a driving force. Comparison of the theory with experimental results clearly supports the concept. The present paper reviews and summarizes these investigations, and arrives at the following conclusions: a) the concept of production bias is consistent with the results of other works which indicates that, under cascade damage conditions, the effective rate of point-defect production is only a small fraction of the NRT displacement production rate; b) the defect accumulation under cascade damage conditions can be understood in terms of production bias; and c) although the existence of conventional dislocation bias due to point-defect dislocation interaction is not questioned, it does not seem to play any major role in the accumulation of defects under cascade damage conditions at elevated temperatures. (orig.)

  4. Forecaster Behaviour and Bias in Macroeconomic Forecasts

    OpenAIRE

    Roy Batchelor

    2007-01-01

    This paper documents the presence of systematic bias in the real GDP and inflation forecasts of private sector forecasters in the G7 economies in the years 1990–2005. The data come from the monthly Consensus Economics forecasting service, and bias is measured and tested for significance using parametric fixed effect panel regressions and nonparametric tests on accuracy ranks. We examine patterns across countries and forecasters to establish whether the bias reflects the inefficient use of i...

  5. U.S. Domestic Reactor Conversion Programs

    International Nuclear Information System (INIS)

    Woolstenhulme, Eric

    2008-01-01

    The Conversion Projects Include: the revision of the facilities safety basis documents and supporting analysis, the fabrication of new LEU fuel, the change-out of the reactor core, and the removal of the used HEU fuel (by INL University Fuels Program or DOE-NE). The major entities involved are: the U.S. Nuclear Regulatory Commission, the University reactor department, the fuel and hardware fabricators, the Spent fuel receipt facilities, the Spent fuel shipping services, and the U.S. Department of Energy and their subcontractors. Three major Reactor Conversion Program milestones have been accomplished since 2006: the conversion of the TRIGA reactor at Texas A and M University Nuclear Science Center, the conversion of the University of Florida Training Reactor, and the conversion of the Purdue University Reactor. Four Reactor Conversion Program milestones yet to be accomplished in 2008 and 2009: the Washington State University Nuclear Radiation Center reactor, the Oregon State University TRIGA Reactor, the University of Wisconsin Nuclear Reactor, and the Neutron Radiography Reactor Facility. NNSA is committed to doing things cheaper, better, smarter, safer through a 'Lessons Learned' process. The conversion team assessed each major activity grouping: Project Initiation, Conversion Proposal Development, Fuel Fabrication and Hardware, Core Conversion, and Spent Nuclear Fuel Removal. Issues were identified and recommendations were given

  6. Modeling Temporal Bias of Uplift Events in Recommender Systems

    KAUST Repository

    Altaf, Basmah

    2013-05-08

    Today, commercial industry spends huge amount of resources in advertisement campaigns, new marketing strategies, and promotional deals to introduce their product to public and attract a large number of customers. These massive investments by a company are worthwhile because marketing tactics greatly influence the consumer behavior. Alternatively, these advertising campaigns have a discernible impact on recommendation systems which tend to promote popular items by ranking them at the top, resulting in biased and unfair decision making and loss of customers’ trust. The biasing impact of popularity of items on recommendations, however, is not fixed, and varies with time. Therefore, it is important to build a bias-aware recommendation system that can rank or predict items based on their true merit at given time frame. This thesis proposes a framework that can model the temporal bias of individual items defined by their characteristic contents, and provides a simple process for bias correction. Bias correction is done either by cleaning the bias from historical training data that is used for building predictive model, or by ignoring the estimated bias from the predictions of a standard predictor. Evaluated on two real world datasets, NetFlix and MovieLens, our framework is shown to be able to estimate and remove the bias as a result of adopted marketing techniques from the predicted popularity of items at a given time.

  7. Special issue: Plasma Conversion

    NARCIS (Netherlands)

    Nozaki, T.; Bogaerts, A.; Tu, X.; van de Sanden, M. C. M.

    2017-01-01

    With growing concern of energy and environmental issues, the combination of plasma and heterogeneous catalysts receives special attention in greenhouse gas conversion, nitrogen fixation and hydrocarbon chemistry. Plasma gas conversion driven by renewable electricity is particularly important for the

  8. Biasing of Capacitive Micromachined Ultrasonic Transducers.

    Science.gov (United States)

    Caliano, Giosue; Matrone, Giulia; Savoia, Alessandro Stuart

    2017-02-01

    Capacitive micromachined ultrasonic transducers (CMUTs) represent an effective alternative to piezoelectric transducers for medical ultrasound imaging applications. They are microelectromechanical devices fabricated using silicon micromachining techniques, developed in the last two decades in many laboratories. The interest for this novel transducer technology relies on its full compatibility with standard integrated circuit technology that makes it possible to integrate on the same chip the transducers and the electronics, thus enabling the realization of extremely low-cost and high-performance devices, including both 1-D or 2-D arrays. Being capacitive transducers, CMUTs require a high bias voltage to be properly operated in pulse-echo imaging applications. The typical bias supply residual ripple of high-quality high-voltage (HV) generators is in the millivolt range, which is comparable with the amplitude of the received echo signals, and it is particularly difficult to minimize. The aim of this paper is to analyze the classical CMUT biasing circuits, highlighting the features of each one, and to propose two novel HV generator architectures optimized for CMUT biasing applications. The first circuit proposed is an ultralow-residual ripple (generator that uses an extremely stable sinusoidal power oscillator topology. The second circuit employs a commercially available integrated step-up converter characterized by a particularly efficient switching topology. The circuit is used to bias the CMUT by charging a buffer capacitor synchronously with the pulsing sequence, thus reducing the impact of the switching noise on the received echo signals. The small area of the circuit (about 1.5 cm 2 ) makes it possible to generate the bias voltage inside the probe, very close to the CMUT, making the proposed solution attractive for portable applications. Measurements and experiments are shown to demonstrate the effectiveness of the new approaches presented.

  9. A theoretical model for analysing gender bias in medicine.

    Science.gov (United States)

    Risberg, Gunilla; Johansson, Eva E; Hamberg, Katarina

    2009-08-03

    During the last decades research has reported unmotivated differences in the treatment of women and men in various areas of clinical and academic medicine. There is an ongoing discussion on how to avoid such gender bias. We developed a three-step-theoretical model to understand how gender bias in medicine can occur and be understood. In this paper we present the model and discuss its usefulness in the efforts to avoid gender bias. In the model gender bias is analysed in relation to assumptions concerning difference/sameness and equity/inequity between women and men. Our model illustrates that gender bias in medicine can arise from assuming sameness and/or equity between women and men when there are genuine differences to consider in biology and disease, as well as in life conditions and experiences. However, gender bias can also arise from assuming differences when there are none, when and if dichotomous stereotypes about women and men are understood as valid. This conceptual thinking can be useful for discussing and avoiding gender bias in clinical work, medical education, career opportunities and documents such as research programs and health care policies. Too meet the various forms of gender bias, different facts and measures are needed. Knowledge about biological differences between women and men will not reduce bias caused by gendered stereotypes or by unawareness of health problems and discrimination associated with gender inequity. Such bias reflects unawareness of gendered attitudes and will not change by facts only. We suggest consciousness-rising activities and continuous reflections on gender attitudes among students, teachers, researchers and decision-makers.

  10. Addressing Unconscious Bias: Steps toward an Inclusive Scientific Culture

    Science.gov (United States)

    Stewart, Abigail

    2011-01-01

    In this talk I will outline the nature of unconscious bias, as it operates to exclude or marginalize some participants in the scientific community. I will show how bias results from non-conscious expectations about certain groups of people, including scientists and astronomers. I will outline scientific research in psychology, sociology and economics that has identified the impact these expectations have on interpersonal judgments that are at the heart of assessment of individuals' qualifications. This research helps us understand not only how bias operates within a single instance of evaluation, but how evaluation bias can accumulate over a career if not checked, creating an appearance of confirmation of biased expectations. Some research has focused on how best to interrupt and mitigate unconscious bias, and many institutions--including the University of Michigan--have identified strategic interventions at key points of institutional decision-making (particularly hiring, annual review, and promotion) that can make a difference. The NSF ADVANCE Institutional Transformation program encouraged institutions to draw on the social science literature to create experimental approaches to addressing unconscious bias. I will outline four approaches to intervention that have arisen through the ADVANCE program: (1) systematic education that increases awareness among decisionmakers of how evaluation bias operates; (2) development of practices that mitigate the operation of bias even when it is out of conscious awareness; (3) creation of institutional policies that routinize and sanction these practices; and (4) holding leaders accountable for these implementation of these new practices and policies. Although I will focus on ways to address unconscious bias within scientific institutions (colleges and universities, laboratories and research centers, etc.), I will close by considering how scientific organizations can address unconscious bias and contribute to creating an

  11. Hemispheric biases and the control of visuospatial attention: an ERP study

    Directory of Open Access Journals (Sweden)

    Banich Marie T

    2005-08-01

    Full Text Available Abstract Background We examined whether individual differences in hemispheric utilization can interact with the intrinsic attentional biases of the cerebral hemispheres. Evidence suggests that the hemispheres have competing biases to direct attention contralaterally, with the left hemisphere (LH having a stronger bias than the right hemisphere. There is also evidence that individuals have characteristic biases to utilize one hemisphere more than the other for processing information, which can induce a bias to direct attention to contralateral space. We predicted that LH-biased individuals would display a strong rightward attentional bias, which would create difficulty in selectively attending to target stimuli in the left visual field (LVF as compared to right in the performance of a bilateral flanker task. Results Consistent with our hypothesis, flanker interference effects were found on the N2c event-related brain potential and error rate for LH-biased individuals in the Attend-LVF condition. The error rate effect was correlated with the degree of hemispheric utilization bias for the LH-Bias group. Conclusion We conclude that hemispheric utilization bias can enhance a hemisphere's contralateral attentional bias, at least for individuals with a LH utilization bias. Hemispheric utilization bias may play an important and largely unrecognized role in visuospatial attention.

  12. Recombination-dependent replication and gene conversion homogenize repeat sequences and diversify plastid genome structure.

    Science.gov (United States)

    Ruhlman, Tracey A; Zhang, Jin; Blazier, John C; Sabir, Jamal S M; Jansen, Robert K

    2017-04-01

    There is a misinterpretation in the literature regarding the variable orientation of the small single copy region of plastid genomes (plastomes). The common phenomenon of small and large single copy inversion, hypothesized to occur through intramolecular recombination between inverted repeats (IR) in a circular, single unit-genome, in fact, more likely occurs through recombination-dependent replication (RDR) of linear plastome templates. If RDR can be primed through both intra- and intermolecular recombination, then this mechanism could not only create inversion isomers of so-called single copy regions, but also an array of alternative sequence arrangements. We used Illumina paired-end and PacBio single-molecule real-time (SMRT) sequences to characterize repeat structure in the plastome of Monsonia emarginata (Geraniaceae). We used OrgConv and inspected nucleotide alignments to infer ancestral nucleotides and identify gene conversion among repeats and mapped long (>1 kb) SMRT reads against the unit-genome assembly to identify alternative sequence arrangements. Although M. emarginata lacks the canonical IR, we found that large repeats (>1 kilobase; kb) represent ∼22% of the plastome nucleotide content. Among the largest repeats (>2 kb), we identified GC-biased gene conversion and mapping filtered, long SMRT reads to the M. emarginata unit-genome assembly revealed alternative, substoichiometric sequence arrangements. We offer a model based on RDR and gene conversion between long repeated sequences in the M. emarginata plastome and provide support that both intra-and intermolecular recombination between large repeats, particularly in repeat-rich plastomes, varies unit-genome structure while homogenizing the nucleotide sequence of repeats. © 2017 Botanical Society of America.

  13. Attentional bias modification encourages healthy eating.

    Science.gov (United States)

    Kakoschke, Naomi; Kemps, Eva; Tiggemann, Marika

    2014-01-01

    The continual exposure to unhealthy food cues in the environment encourages poor dietary habits, in particular consuming too much fat and sugar, and not enough fruit and vegetables. According to Berridge's (2009) model of food reward, unhealthy eating is a behavioural response to biased attentional processing. The present study used an established attentional bias modification paradigm to discourage the consumption of unhealthy food and instead promote healthy eating. Participants were 146 undergraduate women who were randomly assigned to two groups: one was trained to direct their attention toward pictures of healthy food ('attend healthy' group) and the other toward unhealthy food ('attend unhealthy' group). It was found that participants trained to attend to healthy food cues demonstrated an increased attentional bias for such cues and ate relatively more of the healthy than unhealthy snacks compared to the 'attend unhealthy' group. Theoretically, the results support the postulated link between biased attentional processing and consumption (Berridge, 2009). At a practical level, they offer potential scope for interventions that focus on eating well. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Short Communication: Gender Bias and Stigmatization against ...

    African Journals Online (AJOL)

    Short Communication: Gender Bias and Stigmatization against Women Living with ... In Ethiopia, HIV/AIDS is highly stigmatized due to the fact that sexual ... bias, socio-economic situations and traditional beliefs contribute, individually and in ...

  15. Awareness and minimisation of systematic bias in research.

    LENUS (Irish Health Repository)

    Malone, Helen

    2014-03-01

    A major goal of nursing and midwifery is the delivery of evidence-based practice. Consequently, it is essential for the quality and safety of patient\\/client care that policy makers, educators and practitioners are aware of the presence of potential systematic bias in research practice and research publications so that only sound evidence translates into practice. The main aim of this paper is to highlight the need for ongoing awareness of the potential presence of systematic bias in research practice, to explore commonly reported types of systematic bias and to report some methods that can be applied to minimise systematic bias in research.

  16. Cognitive bias in action: evidence for a reciprocal relation between confirmation bias and fear in children.

    Science.gov (United States)

    Remmerswaal, Danielle; Huijding, Jorg; Bouwmeester, Samantha; Brouwer, Marlies; Muris, Peter

    2014-03-01

    Some cognitive models propose that information processing biases and fear are reciprocally related. This idea has never been formally tested. Therefore, this study investigated the existence of a vicious circle by which confirmation bias and fear exacerbate each other. One-hundred-and-seventy-one school children (8-13 years) were first provided with threatening, ambiguous, or positive information about an unknown animal. Then they completed a computerized information search task during which they could collect additional (negative, positive, or neutral) information about the novel animal. Because fear levels were repeatedly assessed during the task, it was possible to examine the reciprocal relationship between confirmation bias and fear. A reciprocal relation of mutual reinforcement was found between confirmation bias and fear over the course of the experiment: increases in fear predicted subsequent increases in the search for negative information, and increases in the search for negative information further enhanced fear on a later point-in-time. In addition, the initial information given about the animals successfully induced diverging fear levels in the children, and determined their first inclination to search for additional information. As this study employed a community sample of primary school children, future research should test whether these results can be generalized to clinically anxious youth. These findings provide first support for the notion that fearful individuals may become trapped in a vicious circle in which fear and a fear-related confirmation bias mutually strengthen each other, thereby maintaining the anxiety pathology. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Increasing conversion efficiency of two-step photon up-conversion solar cell with a voltage booster hetero-interface.

    Science.gov (United States)

    Asahi, Shigeo; Kusaki, Kazuki; Harada, Yukihiro; Kita, Takashi

    2018-01-17

    Development of high-efficiency solar cells is one of the attractive challenges in renewable energy technologies. Photon up-conversion can reduce the transmission loss and is one of the promising concepts which improve conversion efficiency. Here we present an analysis of the conversion efficiency, which can be increased by up-conversion in a single-junction solar cell with a hetero-interface that boosts the output voltage. We confirm that an increase in the quasi-Fermi gap and substantial photocurrent generation result in a high conversion efficiency.

  18. Mood-congruent free recall bias in anxious individuals is not a consequence of response bias

    OpenAIRE

    Russo, Riccardo; Whittuck, Dora; Roberson, Debi; Dutton, Kevin; Georgiou, George; Fox, Elaine

    2006-01-01

    The status of mood-congruent free recall bias in anxious individuals was evaluated following incidental encoding of target words. Individuals with high and low levels of trait anxiety completed a modified Stroop task, which revealed an attentional bias for threat-related stimuli in anxious individuals. This group was significantly slower in naming the colour in which threat-related words were displayed compared to neutral words. In a subsequent free recall test for the words used in the modif...

  19. Gender Bias: Inequities in the Classroom.

    Science.gov (United States)

    Love, Reeve

    1993-01-01

    This article explores sex bias in curricular materials for elementary and secondary schools. Sex bias is defined as a set of unconscious behaviors that, in themselves, are often trivial and generally favorable. Although these behaviors do not hurt if they happen only once, they can cause a great deal of harm if a pattern develops that serves to…

  20. Sources of bias in clinical ethics case deliberation.

    Science.gov (United States)

    Magelssen, Morten; Pedersen, Reidar; Førde, Reidun

    2014-10-01

    A central task for clinical ethics consultants and committees (CEC) is providing analysis of, and advice on, prospective or retrospective clinical cases. However, several kinds of biases may threaten the integrity, relevance or quality of the CEC's deliberation. Bias should be identified and, if possible, reduced or counteracted. This paper provides a systematic classification of kinds of bias that may be present in a CEC's case deliberation. Six kinds of bias are discussed, with examples, as to their significance and risk factors. Possible remedies are suggested. The potential for bias is greater when the case deliberation is performed by an individual ethics consultant than when an entire clinical ethics committee is involved. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  1. Cognitive bias in forensic anthropology: visual assessment of skeletal remains is susceptible to confirmation bias.

    Science.gov (United States)

    Nakhaeizadeh, Sherry; Dror, Itiel E; Morgan, Ruth M

    2014-05-01

    An experimental study was designed to examine cognitive biases within forensic anthropological non-metric methods in assessing sex, ancestry and age at death. To investigate examiner interpretation, forty-one non-novice participants were semi randomly divided into three groups. Prior to conducting the assessment of the skeletal remains, two of the groups were given different extraneous contextual information regarding the sex, ancestry and age at death of the individual. The third group acted as a control group with no extraneous contextual information. The experiment was designed to investigate if the interpretation and conclusions of the skeletal remains would differ amongst participants within the three groups, and to assess whether the examiners would confirm or disagree with the given extraneous context when establishing a biological profile. The results revealed a significant biasing effect within the three groups, demonstrating a strong confirmation bias in the assessment of sex, ancestry and age at death. In assessment of sex, 31% of the participants in the control group concluded that the skeleton remains were male. In contrast, in the group that received contextual information that the remains were male, 72% concluded that the remains were male, and in the participant group where the context was that the remains were of a female, 0% of the participants concluded that the remains were male. Comparable results showing bias were found in assessing ancestry and age at death. These data demonstrate that cognitive bias can impact forensic anthropological non-metric methods on skeletal remains and affects the interpretation and conclusions of the forensic scientists. This empirical study is a step in establishing an evidence base approach for dealing with cognitive issues in forensic anthropological assessments, so as to enhance this valuable forensic science discipline. Copyright © 2013 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights

  2. Gain compensation technique by bias correction in arrays of Silicon Photomultipliers using fully differential fast shaper

    Energy Technology Data Exchange (ETDEWEB)

    Baszczyk, M., E-mail: baszczyk@agh.edu.pl [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); Dorosz, P.; Glab, S.; Kucewicz, W. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); Mik, L. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); State Higher Vocational School, Tarnow (Poland); Sapor, M. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland)

    2016-07-11

    Proposed algorithm compensates the gain by changing the bias voltage of Silicon Photomultipliers (SiPM). The signal from SiPM is amplified in fully differential preamplifier then is formed in time by the fully differential fast shaper. The compensation method was tested with four channels common cathode multi-pixel photon counter from Hamamatsu. The measurement system requires only one high voltage power supply. The polarization voltage is adjusted individually in each channel indirectly by tuning the output common mode voltage (VOCM) of fully differential amplifier. The changes of VOCM affect the input voltage through the feedback network. Actual gain of the SiPM is calculated by measuring the mean amplitude of the signal resulting from detection of single photoelectron. The VOCM is adjusted by DAC so as to reach the desired value of gain by each channel individually. The advantage of the algorithm is the possibility to set the bias of each SiPM in the array independently so they all could operate in very similar conditions (have similar gain and dark count rate). The algorithm can compensate the variations of gain of SiPM by using thermally generated pulses. There is no need to use additional current to voltage conversion which could introduce extra noises.

  3. Gain compensation technique by bias correction in arrays of Silicon Photomultipliers using fully differential fast shaper

    Science.gov (United States)

    Baszczyk, M.; Dorosz, P.; Glab, S.; Kucewicz, W.; Mik, L.; Sapor, M.

    2016-07-01

    Proposed algorithm compensates the gain by changing the bias voltage of Silicon Photomultipliers (SiPM). The signal from SiPM is amplified in fully differential preamplifier then is formed in time by the fully differential fast shaper. The compensation method was tested with four channels common cathode multi-pixel photon counter from Hamamatsu. The measurement system requires only one high voltage power supply. The polarization voltage is adjusted individually in each channel indirectly by tuning the output common mode voltage (VOCM) of fully differential amplifier. The changes of VOCM affect the input voltage through the feedback network. Actual gain of the SiPM is calculated by measuring the mean amplitude of the signal resulting from detection of single photoelectron. The VOCM is adjusted by DAC so as to reach the desired value of gain by each channel individually. The advantage of the algorithm is the possibility to set the bias of each SiPM in the array independently so they all could operate in very similar conditions (have similar gain and dark count rate). The algorithm can compensate the variations of gain of SiPM by using thermally generated pulses. There is no need to use additional current to voltage conversion which could introduce extra noises.

  4. Gain compensation technique by bias correction in arrays of Silicon Photomultipliers using fully differential fast shaper

    International Nuclear Information System (INIS)

    Baszczyk, M.; Dorosz, P.; Glab, S.; Kucewicz, W.; Mik, L.; Sapor, M.

    2016-01-01

    Proposed algorithm compensates the gain by changing the bias voltage of Silicon Photomultipliers (SiPM). The signal from SiPM is amplified in fully differential preamplifier then is formed in time by the fully differential fast shaper. The compensation method was tested with four channels common cathode multi-pixel photon counter from Hamamatsu. The measurement system requires only one high voltage power supply. The polarization voltage is adjusted individually in each channel indirectly by tuning the output common mode voltage (VOCM) of fully differential amplifier. The changes of VOCM affect the input voltage through the feedback network. Actual gain of the SiPM is calculated by measuring the mean amplitude of the signal resulting from detection of single photoelectron. The VOCM is adjusted by DAC so as to reach the desired value of gain by each channel individually. The advantage of the algorithm is the possibility to set the bias of each SiPM in the array independently so they all could operate in very similar conditions (have similar gain and dark count rate). The algorithm can compensate the variations of gain of SiPM by using thermally generated pulses. There is no need to use additional current to voltage conversion which could introduce extra noises.

  5. News Consumption and Media Bias

    OpenAIRE

    Yi Xiang; Miklos Sarvary

    2007-01-01

    Bias in the market for news is well-documented. Recent research in economics explains the phenomenon by assuming that consumers want to read (watch) news that is consistent with their tastes or prior beliefs rather than the truth. The present paper builds on this idea but recognizes that (i) besides “biased” consumers, there are also “conscientious” consumers whose sole interest is in discovering the truth, and (ii) consistent with reality, media bias is constrained by the truth. These two fa...

  6. Ownership conversions and nursing home performance.

    Science.gov (United States)

    Grabowski, David C; Stevenson, David G

    2008-08-01

    To examine the effects of ownership conversions on nursing home performance. Online Survey, Certification, and Reporting system data from 1993 to 2004, and the Minimum Data Set (MDS) facility reports from 1998 to 2004. Regression specification incorporating facility fixed effects, with terms to identify trends in the pre- and postconversion periods. The annual rate of nursing home conversions almost tripled between 1994 and 2004. Our regression results indicate converting facilities are generally different throughout the pre/postconversion years, suggesting little causal effect of ownership conversions on nursing home performance. Before and after conversion, nursing homes converting from nonprofit to for-profit status generally exhibit deterioration in their performance, while nursing homes converting from for-profit to nonprofit status generally exhibit improvement. Policy makers have expressed concern regarding the implications of ownership conversions for nursing home performance. Our results imply that regulators and policy makers should not only monitor the outcomes of nursing home conversions, but also the targets of these conversions.

  7. Specificity and overlap of attention and memory biases in depression.

    Science.gov (United States)

    Marchetti, Igor; Everaert, Jonas; Dainer-Best, Justin; Loeys, Tom; Beevers, Christopher G; Koster, Ernst H W

    2018-01-01

    Attentional and memory biases are viewed as crucial cognitive processes underlying symptoms of depression. However, it is still unclear whether these two biases are uniquely related to depression or whether they show substantial overlap. We investigated the degree of specificity and overlap of attentional and memory biases for depressotypic stimuli in relation to depression and anxiety by means of meta-analytic commonality analysis. By including four published studies, we considered a pool of 463 healthy and subclinically depressed individuals, different experimental paradigms, and different psychological measures. Memory bias is reliably and strongly related to depression and, specifically, to symptoms of negative mood, worthlessness, feelings of failure, and pessimism. Memory bias for negative information was minimally related to anxiety. Moreover, neither attentional bias nor the overlap between attentional and memory biases were significantly related to depression. Limitations include cross-sectional nature of the study. Our study showed that, across different paradigms and psychological measures, memory bias (and not attentional bias) represents a primary mechanism in depression. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. A theoretical model for analysing gender bias in medicine

    Directory of Open Access Journals (Sweden)

    Johansson Eva E

    2009-08-01

    Full Text Available Abstract During the last decades research has reported unmotivated differences in the treatment of women and men in various areas of clinical and academic medicine. There is an ongoing discussion on how to avoid such gender bias. We developed a three-step-theoretical model to understand how gender bias in medicine can occur and be understood. In this paper we present the model and discuss its usefulness in the efforts to avoid gender bias. In the model gender bias is analysed in relation to assumptions concerning difference/sameness and equity/inequity between women and men. Our model illustrates that gender bias in medicine can arise from assuming sameness and/or equity between women and men when there are genuine differences to consider in biology and disease, as well as in life conditions and experiences. However, gender bias can also arise from assuming differences when there are none, when and if dichotomous stereotypes about women and men are understood as valid. This conceptual thinking can be useful for discussing and avoiding gender bias in clinical work, medical education, career opportunities and documents such as research programs and health care policies. Too meet the various forms of gender bias, different facts and measures are needed. Knowledge about biological differences between women and men will not reduce bias caused by gendered stereotypes or by unawareness of health problems and discrimination associated with gender inequity. Such bias reflects unawareness of gendered attitudes and will not change by facts only. We suggest consciousness-rising activities and continuous reflections on gender attitudes among students, teachers, researchers and decision-makers.

  9. Editorial Bias in Crowd-Sourced Political Information.

    Directory of Open Access Journals (Sweden)

    Joshua L Kalla

    Full Text Available The Internet has dramatically expanded citizens' access to and ability to engage with political information. On many websites, any user can contribute and edit "crowd-sourced" information about important political figures. One of the most prominent examples of crowd-sourced information on the Internet is Wikipedia, a free and open encyclopedia created and edited entirely by users, and one of the world's most accessed websites. While previous studies of crowd-sourced information platforms have found them to be accurate, few have considered biases in what kinds of information are included. We report the results of four randomized field experiments that sought to explore what biases exist in the political articles of this collaborative website. By randomly assigning factually true but either positive or negative and cited or uncited information to the Wikipedia pages of U.S. senators, we uncover substantial evidence of an editorial bias toward positivity on Wikipedia: Negative facts are 36% more likely to be removed by Wikipedia editors than positive facts within 12 hours and 29% more likely within 3 days. Although citations substantially increase an edit's survival time, the editorial bias toward positivity is not eliminated by inclusion of a citation. We replicate this study on the Wikipedia pages of deceased as well as recently retired but living senators and find no evidence of an editorial bias in either. Our results demonstrate that crowd-sourced information is subject to an editorial bias that favors the politically active.

  10. Editorial Bias in Crowd-Sourced Political Information.

    Science.gov (United States)

    Kalla, Joshua L; Aronow, Peter M

    2015-01-01

    The Internet has dramatically expanded citizens' access to and ability to engage with political information. On many websites, any user can contribute and edit "crowd-sourced" information about important political figures. One of the most prominent examples of crowd-sourced information on the Internet is Wikipedia, a free and open encyclopedia created and edited entirely by users, and one of the world's most accessed websites. While previous studies of crowd-sourced information platforms have found them to be accurate, few have considered biases in what kinds of information are included. We report the results of four randomized field experiments that sought to explore what biases exist in the political articles of this collaborative website. By randomly assigning factually true but either positive or negative and cited or uncited information to the Wikipedia pages of U.S. senators, we uncover substantial evidence of an editorial bias toward positivity on Wikipedia: Negative facts are 36% more likely to be removed by Wikipedia editors than positive facts within 12 hours and 29% more likely within 3 days. Although citations substantially increase an edit's survival time, the editorial bias toward positivity is not eliminated by inclusion of a citation. We replicate this study on the Wikipedia pages of deceased as well as recently retired but living senators and find no evidence of an editorial bias in either. Our results demonstrate that crowd-sourced information is subject to an editorial bias that favors the politically active.

  11. A systematic review of context bias in invasion biology.

    Directory of Open Access Journals (Sweden)

    Robert J Warren

    Full Text Available The language that scientists use to frame biological invasions may reveal inherent bias-including how data are interpreted. A frequent critique of invasion biology is the use of value-laden language that may indicate context bias. Here we use a systematic study of language and interpretation in papers drawn from invasion biology to evaluate whether there is a link between the framing of papers and the interpretation of results. We also examine any trends in context bias in biological invasion research. We examined 651 peer-reviewed invasive species competition studies and implemented a rigorous systematic review to examine bias in the presentation and interpretation of native and invasive competition in invasion biology. We predicted that bias in the presentation of invasive species is increasing, as suggested by several authors, and that bias against invasive species would result in misinterpreting their competitive dominance in correlational observational studies compared to causative experimental studies. We indeed found evidence of bias in the presentation and interpretation of invasive species research; authors often introduced research with invasive species in a negative context and study results were interpreted against invasive species more in correlational studies. However, we also found a distinct decrease in those biases since the mid-2000s. Given that there have been several waves of criticism from scientists both inside and outside invasion biology, our evidence suggests that the subdiscipline has somewhat self-corrected apparent biases.

  12. A systematic review of context bias in invasion biology.

    Science.gov (United States)

    Warren, Robert J; King, Joshua R; Tarsa, Charlene; Haas, Brian; Henderson, Jeremy

    2017-01-01

    The language that scientists use to frame biological invasions may reveal inherent bias-including how data are interpreted. A frequent critique of invasion biology is the use of value-laden language that may indicate context bias. Here we use a systematic study of language and interpretation in papers drawn from invasion biology to evaluate whether there is a link between the framing of papers and the interpretation of results. We also examine any trends in context bias in biological invasion research. We examined 651 peer-reviewed invasive species competition studies and implemented a rigorous systematic review to examine bias in the presentation and interpretation of native and invasive competition in invasion biology. We predicted that bias in the presentation of invasive species is increasing, as suggested by several authors, and that bias against invasive species would result in misinterpreting their competitive dominance in correlational observational studies compared to causative experimental studies. We indeed found evidence of bias in the presentation and interpretation of invasive species research; authors often introduced research with invasive species in a negative context and study results were interpreted against invasive species more in correlational studies. However, we also found a distinct decrease in those biases since the mid-2000s. Given that there have been several waves of criticism from scientists both inside and outside invasion biology, our evidence suggests that the subdiscipline has somewhat self-corrected apparent biases.

  13. Body image related negative interpretation bias in anorexia nervosa.

    Science.gov (United States)

    Brockmeyer, Timo; Anderle, Alisa; Schmidt, Hagen; Febry, Stephanie; Wünsch-Leiteritz, Wally; Leiteritz, Andreas; Friederich, Hans-Christoph

    2018-05-01

    A distorted body image and pronounced body dissatisfaction are hallmarks of anorexia nervosa (AN) that typically result in dietary restraint and compensatory behaviours. Cognitive biases such as negative interpretation bias are considered key maintaining factors of these maladaptive cognitions and behaviours. However, little attention has been paid to empirical tests whether negative interpretation bias exists in AN and to what degree it is associated with symptom severity. Participants in the present study were 40 women with AN and 40 healthy women with no history of an eating disorder. Body-related negative interpretation bias (i.e., a tendency to interpret ambiguous information about the own body in a negative way) was measured by a Scrambled Sentences Task. Patients with AN showed a stronger body-related negative interpretation bias than healthy controls. Within both groups, negative interpretation bias correlated strongly and positively with AN symptom severity and these effects were not moderated by levels of depressive symptoms. The findings support the idea that biased interpretation of body-related information is associated with the specific psychopathology of AN. Targeted, computerised interventions (e.g. interpretation bias modification) may help to alter these dysfunctional cognitive schemas that lie at the heart of AN. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Multilayer DLC coatings via alternating bias during magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Li Fengji [School of Mechanical and Aerospace Engineering, Nanyang Technological University (Singapore); Zhang, Sam, E-mail: msyzhang@ntu.edu.sg [School of Mechanical and Aerospace Engineering, Nanyang Technological University (Singapore); Kong Junhua [School of Materials Science and Engineering, Nanyang Technological University (Singapore); Zhang Yujuan [Key Laboratory of Special Functional Material, Henan University (China); Zhang Wali [School of Mechanical and Aerospace Engineering, Nanyang Technological University (Singapore)

    2011-05-31

    To combat the high residual stress problem in monolayer diamond-like carbon coatings, this paper fabricated multilayer diamond-like carbon coatings with alternate soft and hard layers via alternating bias during magnetron sputtering. The surface, cross sectional morphology, bonding structures and mechanical properties are investigated. The atomic force microscopy images indicate low bias results in rougher surface with large graphite clusters and voids suggesting low coating density. The multilayered coatings demonstrate relatively smooth surface stemming from higher bias. The cross sectional images from field emission scanning electron microscopy indicate coating thickness decreases as substrate bias increases and confirm that higher bias results in denser coating. Delamination is observed in monolayer coatings due to high residual stress. The trend of sp{sup 3}/sp{sup 2} fraction estimated by X-ray photoelectron spectroscopy is consistent with that of I{sub D}/I{sub G} ratios from Raman spectra, indicating the change of bonding structure with change of substrate bias. Hardness of multilayer diamond-like carbon coating is comparable to the coatings deposited at low constant bias but the adhesion strength and toughness are significantly improved. Alternately biased sputtering deposition provides an alternative when combination of hardness, toughness and adhesion strength is needed in an all diamond-like carbon coating.

  15. Decision-making heuristics and biases across the life span.

    Science.gov (United States)

    Strough, Jonell; Karns, Tara E; Schlosnagle, Leo

    2011-10-01

    We outline a contextual and motivational model of judgment and decision-making (JDM) biases across the life span. Our model focuses on abilities and skills that correspond to deliberative, experiential, and affective decision-making processes. We review research that addresses links between JDM biases and these processes as represented by individual differences in specific abilities and skills (e.g., fluid and crystallized intelligence, executive functioning, emotion regulation, personality traits). We focus on two JDM biases-the sunk-cost fallacy (SCF) and the framing effect. We trace the developmental trajectory of each bias from preschool through middle childhood, adolescence, early adulthood, and later adulthood. We conclude that life-span developmental trajectories differ depending on the bias investigated. Existing research suggests relative stability in the framing effect across the life span and decreases in the SCF with age, including in later life. We highlight directions for future research on JDM biases across the life span, emphasizing the need for process-oriented research and research that increases our understanding of JDM biases in people's everyday lives. © 2011 New York Academy of Sciences.

  16. Cognitive bias in symptomatic and recovered agoraphobics.

    Science.gov (United States)

    Stoler, L S; McNally, R J

    1991-01-01

    Symptomatic agoraphobics, recovered agoraphobics, and normal control subjects completed a series of sentence stems that had either ambiguous or unambiguous meanings, and had either a potentially threatening or a nonthreatening connotation. The written completions made by subjects to these stems were classified as indicating either a biased (i.e. threat-related) or unbiased interpretation of the meaning of the stem, and if a biased interpretation was made, whether the subject indicated efforts at adaptive coping with the perceived threat. Results indicated that symptomatic agoraphobics exhibited strong biases for interpreting information as threatening, relative to normal control subjects. Moreover, recovered agoraphobics resembled symptomatic agoraphobics more than normal control subjects, thus indicating that cognitive biases may persist following cessation of panic attacks and reductions in avoidance behavior. However, recovered agoraphobics also exhibited tendencies to cope adaptively with perceived threats whereas symptomatic agoraphobics did not.

  17. High-Q perpendicular-biased ferrite-tuned cavity

    International Nuclear Information System (INIS)

    Carlini, R.D.; Thiessen, H.A.; Potter, J.M.

    1983-01-01

    Rapid-cycling proton synchrotrons, such as the proposed LAMPF II accelerator, require approximately 10 MV per turn rf with 17% tuning range near 50 MHz. The traditional approach to ferrite-tuned cavities uses a ferrite which is longitudinally biased (rf magnetic field parallel to bias field). This method leads to unacceptably high losses in the ferrite. At Los Alamos, we are developing a cavity with transverse bias (rf magnetic field perpendicular to the bias field) that makes use of the tensor permeability of the ferrite. Modest power tests of a small (10-cm-dia) quarter-wave singly re-entrant cavity tuned by nickel-zinc ferrites and aluminum-doped garnets indicate that the losses in the ferrite can be made negligible compared with the losses due to the surface resistivity of the copper cavity at power levels from 2 to 200 watts

  18. Monte Carlo shielding analyses using an automated biasing procedure

    International Nuclear Information System (INIS)

    Tang, J.S.; Hoffman, T.J.

    1988-01-01

    A systematic and automated approach for biasing Monte Carlo shielding calculations is described. In particular, adjoint fluxes from a one-dimensional discrete ordinates calculation are used to generate biasing parameters for a Monte Carlo calculation. The entire procedure of adjoint calculation, biasing parameters generation, and Monte Carlo calculation has been automated. The automated biasing procedure has been applied to several realistic deep-penetration shipping cask problems. The results obtained for neutron and gamma-ray transport indicate that with the automated biasing procedure Monte Carlo shielding calculations of spent-fuel casks can be easily performed with minimum effort and that accurate results can be obtained at reasonable computing cost

  19. Hydrothermal conversion of biomass

    NARCIS (Netherlands)

    Knezevic, D.

    2009-01-01

    This thesis presents research of hydrothermal conversion of biomass (HTC). In this process, hot compressed water (subcritical water) is used as the reaction medium. Therefore this technique is suitable for conversion of wet biomass/ waste streams. By working at high pressures, the evaporation of

  20. Reducing status quo bias in choice experiments

    DEFF Research Database (Denmark)

    Bonnichsen, Ole; Ladenburg, Jacob

    In stated preference literature, the tendency to choose the alternative representing the status quo situation seems to exceed real life status quo effects. Accordingly, status quo bias can be a problem. In Choice Experiments, status quo bias is found to be strongly correlated with protest attitudes...... toward the cost attribute. If economic values are to be elicited, this problem is difficult to remedy. In a split sample framework we test a novel ex-ante entreaty aimed specifically at the cost attribute and find that it effectively reduces status quo bias and improves the internal validity...

  1. Biased agonism of the calcium-sensing receptor

    DEFF Research Database (Denmark)

    Thomsen, Alex Rojas Bie; Hvidtfeldt, Maja; Bräuner-Osborne, Hans

    2012-01-01

    After the discovery of molecules modulating G protein-coupled receptors (GPCRs) that are able to selectively affect one signaling pathway over others for a specific GPCR, thereby "biasing" the signaling, it has become obvious that the original model of GPCRs existing in either an "on" or "off...... through recruitment of ß-arrestins. Next, by measuring activity of all three signaling pathways we found that barium, spermine, neomycin, and tobramycin act as biased agonist in terms of efficacy and/or potency. Finally, polyamines and aminoglycosides in general were biased in their potencies toward ERK1...

  2. On the Borders of Harmful and Helpful Beauty Biases

    OpenAIRE

    Maria Agthe; Maria Strobel; Matthias Spörrle; Michaela Pfundmair; Jon K. Maner

    2016-01-01

    Research with European Caucasian samples demonstrates that attractiveness-based biases in social evaluation depend on the constellation of the sex of the evaluator and the sex of the target: Whereas people generally show positive biases toward attractive opposite-sex persons, they show less positive or even negative biases toward attractive same-sex persons. By examining these biases both within and between different ethnicities, the current studies provide new evidence for both the generaliz...

  3. Ironic effects of racial bias during interracial interactions.

    Science.gov (United States)

    Shelton, J Nicole; Richeson, Jennifer A; Salvatore, Jessica; Trawalter, Sophie

    2005-05-01

    Previous research has suggested that Blacks like White interaction partners who make an effort to appear unbiased more than those who do not. We tested the hypothesis that, ironically, Blacks perceive White interaction partners who are more racially biased more positively than less biased White partners, primarily because the former group must make more of an effort to control racial bias than the latter. White participants in this study completed the Implicit Association Test (IAT) as a measure of racial bias and then discussed race relations with either a White or a Black partner. Whites' IAT scores predicted how positively they were perceived by Black (but not White) interaction partners, and this relationship was mediated by Blacks' perceptions of how engaged the White participants were during the interaction. We discuss implications of the finding that Blacks may, ironically, prefer to interact with highly racially biased Whites, at least in short interactions.

  4. Conversational Styles and Misunderstanding in Cross-Sex Conversations in He’s Just Not That into You Movie

    Directory of Open Access Journals (Sweden)

    Ayu Nyoman Aryani

    2017-01-01

    Full Text Available Conversation is a social interaction among societies. In this case, gender differences in daily communication lead to men’s and women’s different point of views in performing styles of the conversations. Misunderstanding is likely to occur in crosssex conversations when the idea or thought are understood differently by men and women. This study was intended to analyze the use of conversational styles by men and women and also investigate the misunderstanding phenomena that happened in cross-sex conversations. The researcher identified that the conversational styles used by Alex as a male character in the cross-sex conversations were qualifiers, controlling the topics, verbal fillers, intensifiers, swear words, compound requests, tag questions, questions, interruptions, overlapping, and talk domination. Meanwhile, Gigi, as a female character used qualifiers, controlling the topics, verbal fillers, intensifiers, swear words, tag questions, questions, interruptions, overlapping, talk domination, and silence. In answering the second question, the researcher discovered factors that affected the misunderstanding in the cross-sex conversations between Alex and Gigi were involvement versus independence and message versus metamessage.   DOI: https://doi.org/10.24071/llt.2016.190101

  5. Skill-Biased Technological Change in Denmark

    DEFF Research Database (Denmark)

    Malchow-Møller, Nikolaj; Rose Skaksen, Jan

    2003-01-01

    Skill-Biased Technological Change in Denmark:A Disaggregate Perspective@*In this paper, we provide an industry-level analysis of skill-biased technological change(SBTC) in Denmark over the last two decades. The analysis shows that SBTC has variedconsiderably across industries, and traditionally...... large Danish industries have experiencedrelatively less SBTC. This may partly explain why wage inequality between skilled and lessskilled has risen less in Denmark than in other countries. We also find that SBTC has beenconcentrated in already skill-intensive industries. This contains important...... information aboutfuture labour requirements, as the relative importance of these industries must be expectedto grow, thereby reinforcing the shift in demand for skilled labour.JEL Classification: J24, J31, L6Keywords: skill-biased technological change, Danish industries...

  6. The Probability Distribution for a Biased Spinner

    Science.gov (United States)

    Foster, Colin

    2012-01-01

    This article advocates biased spinners as an engaging context for statistics students. Calculating the probability of a biased spinner landing on a particular side makes valuable connections between probability and other areas of mathematics. (Contains 2 figures and 1 table.)

  7. Vertical Scan-Conversion for Filling Purposes

    OpenAIRE

    Hersch, R. D.

    1988-01-01

    Conventional scan-conversion algorithms were developed independently of filling algorithms. They cause many problems, when used for filling purposes. However, today's raster printers and plotters require extended use of filling, especially for the generation of typographic characters and graphic line art. A new scan-conversion algorithm, called vertical scan-conversion has been specifically designed to meet the requirements of parity scan line fill algorithms. Vertical scan-conversion ensures...

  8. The lighter side of advertising: investigating posing and lighting biases.

    Science.gov (United States)

    Thomas, Nicole A; Burkitt, Jennifer A; Patrick, Regan E; Elias, Lorin J

    2008-11-01

    People tend to display the left cheek when posing for a portrait; however, this effect does not appear to generalise to advertising. The amount of body visible in the image and the sex of the poser might also contribute to the posing bias. Portraits also exhibit lateral lighting biases, with most images being lit from the left. This effect might also be present in advertisements. A total of 2801 full-page advertisements were sampled and coded for posing direction, lighting direction, sex of model, and amount of body showing. Images of females showed an overall leftward posing bias, but the biases in males depended on the amount of body visible. Males demonstrated rightward posing biases for head-only images. Overall, images tended to be lit from the top left corner. The two factors of posing and lighting biases appear to influence one another. Leftward-lit images had more leftward poses than rightward, while the opposite occurred for rightward-lit images. Collectively, these results demonstrate that the posing biases in advertisements are dependent on the amount of body showing in the image, and that biases in lighting direction interact with these posing biases.

  9. Imaging the neural effects of cognitive bias modification training

    NARCIS (Netherlands)

    Wiers, C.E.; Wiers, R.W.

    Cognitive bias modification (CBM) was first developed as an experimental tool to examine the causal role of cognitive biases, and later developed into complementary interventions in experimental psychopathology research. CBM involves the "re-training" of implicit biases by means of multiple trials

  10. Importance biasing quality criterion based on contribution response theory

    International Nuclear Information System (INIS)

    Borisov, N.M.; Panin, M.P.

    2001-01-01

    The report proposes a visual criterion of importance biasing both of forward and adjoint simulation. The similarity of contribution Monte Carlo and importance biasing random collision event distribution is proved. The conservation of total number of random trajectory crossings of surfaces, which separate the source and the detector is proposed as importance biasing quality criterion. The use of this criterion is demonstrated on the example of forward vs. adjoint importance biasing in gamma ray deep penetration problem. The larger amount of published data on forward field characteristics than on adjoint leads to the more accurate approximation of adjoint importance function in comparison to forward, for it adjoint importance simulation is more effective than forward. The proposed criterion indicates it visually, showing the most uniform distribution of random trajectory crossing events for the most effective importance biasing parameters and pointing to the direction of tuning importance biasing parameters. (orig.)

  11. Effect of Diffusion Limitations on Multianalyte Determination from Biased Biosensor Response

    Science.gov (United States)

    Baronas, Romas; Kulys, Juozas; Lančinskas, Algirdas; Žilinskas, Antanas

    2014-01-01

    The optimization-based quantitative determination of multianalyte concentrations from biased biosensor responses is investigated under internal and external diffusion-limited conditions. A computational model of a biocatalytic amperometric biosensor utilizing a mono-enzyme-catalyzed (nonspecific) competitive conversion of two substrates was used to generate pseudo-experimental responses to mixtures of compounds. The influence of possible perturbations of the biosensor signal, due to a white noise- and temperature-induced trend, on the precision of the concentration determination has been investigated for different configurations of the biosensor operation. The optimization method was found to be suitable and accurate enough for the quantitative determination of the concentrations of the compounds from a given biosensor transient response. The computational experiments showed a complex dependence of the precision of the concentration estimation on the relative thickness of the outer diffusion layer, as well as on whether the biosensor operates under diffusion- or kinetics-limited conditions. When the biosensor response is affected by the induced exponential trend, the duration of the biosensor action can be optimized for increasing the accuracy of the quantitative analysis. PMID:24608006

  12. Optical analysis of down-conversion OLEDs

    Science.gov (United States)

    Krummacher, Benjamin; Klein, Markus; von Malm, Norwin; Winnacker, Albrecht

    2008-02-01

    Phosphor down-conversion of blue organic light-emitting diodes (OLEDs) is one approach to generate white light, which offers the possibility of easy color tuning, a simple device architecture and color stability over lifetime. In this article previous work on down-conversion devices in the field of organic solid state lighting is briefly reviewed. Further, bottom emitting down-conversion OLEDs are studied from an optical point of view. Therefore the physical processes occurring in the down-conversion layer are translated into a model which is implemented in a ray tracing simulation. By comparing its predictions to experimental results the model is confirmed. For the experiments a blue-emitting polymer OLED (PLED) panel optically coupled to a series of down-conversion layers is used. Based on results obtained from ray tracing simulation some of the implications of the model for the performance of down-conversion OLEDs are discussed. In particular it is analysed how the effective reflectance of the underlying blue OLED and the particle size distribution of the phosphor powder embedded in the matrix of the down-conversion layer influence extraction efficiency.

  13. Investigating vulnerability to eating disorders: biases in emotional processing.

    Science.gov (United States)

    Pringle, A; Harmer, C J; Cooper, M J

    2010-04-01

    Biases in emotional processing and cognitions about the self are thought to play a role in the maintenance of eating disorders (EDs). However, little is known about whether these difficulties exist pre-morbidly and how they might contribute to risk. Female dieters (n=82) completed a battery of tasks designed to assess the processing of social cues (facial emotion recognition), cognitions about the self [Self-Schema Processing Task (SSPT)] and ED-specific cognitions about eating, weight and shape (emotional Stroop). The 26-item Eating Attitudes Test (EAT-26; Garner et al. 1982) was used to assess subclinical ED symptoms; this was used as an index of vulnerability within this at-risk group. Regression analyses showed that biases in the processing of both neutral and angry faces were predictive of our measure of vulnerability (EAT-26). In the self-schema task, biases in the processing of negative self descriptors previously found to be common in EDs predicted vulnerability. Biases in the processing of shape-related words on the Stroop task were also predictive; however, these biases were more important in dieters who also displayed biases in the self-schema task. We were also able to demonstrate that these biases are specific and separable from more general negative biases that could be attributed to depressive symptoms. These results suggest that specific biases in the processing of social cues, cognitions about the self, and also about eating, weight and shape information, may be important in understanding risk and preventing relapse in EDs.

  14. Responsive turns in Indonesian informal conversation

    Directory of Open Access Journals (Sweden)

    M.J. van Naerssen

    2015-04-01

    Full Text Available People have all sorts of expectations about how interlocutors will and should behave linguistically when engaged in a conversation. These conversational norms are usually implicit and are sometimes difficult to master in a language that is new to you. This paper presents a model of different types of responses in informal conversation, illustrated with Indonesian examples. It builds upon the conversation analytic notion of preference; distinguishing preferred – or constructive – responses and dispreferred – or competitive – responses. The model is meant as a tool to cross-linguistically compare response behaviour to gain insight in language specific expectations about interaction in informal conversation.

  15. Biomass Thermochemical Conversion Program: 1986 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.; Stevens, D.J.; Gerber, M.A.

    1987-01-01

    Wood and crop residues constitute a vast majority of the biomass feedstocks available for conversion, and thermochemical processes are well suited for conversion of these materials. Thermochemical conversion processes can generate a variety of products such as gasoline hydrocarbon fuels, natural gas substitutes, or heat energy for electric power generation. The US Department of Energy is sponsoring research on biomass conversion technologies through its Biomass Thermochemical Conversion Program. Pacific Northwest Laboratory has been designated the Technical Field Management Office for the Biomass Thermochemical Conversion Program with overall responsibility for the Program. This report briefly describes the Thermochemical Conversion Program structure and summarizes the activities and major accomplishments during fiscal year 1986. 88 refs., 31 figs., 5 tabs.

  16. Reflecting Equity and Diversity. Part I: Guidelines and Procedure for Evaluating Bias in Instructional Materials. Part II: Bias Awareness Training Worksheets. Part III: Bias Awareness and Procedure Training Course.

    Science.gov (United States)

    Bebermeyer, Jim; Edmond, Mary, Ed.

    Reflecting a need to prepare students for working in diverse organizations, this document was developed to increase school officials' awareness of bias in instructional materials and help them select bias-free materials. A number of the examples illustrate situations dealing with diversity in the workplace. The guide is divided into three parts:…

  17. Conversations in African Philosophy

    African Journals Online (AJOL)

    JONATHAN

    Conversational philosophy is articulated by Jonathan O. Chimakonam as the new wave of philosophical practice both in “place” and in “space”. This journal adopts and promotes this approach to philosophizing for African philosophy. Readers are encouraged to submit their conversational piece (maximum of 2000 words) ...

  18. The self-attribution bias and paranormal beliefs.

    Science.gov (United States)

    van Elk, Michiel

    2017-03-01

    The present study investigated the relation between paranormal beliefs, illusory control and the self-attribution bias, i.e., the motivated tendency to attribute positive outcomes to oneself while negative outcomes are externalized. Visitors of a psychic fair played a card guessing game and indicated their perceived control over randomly selected cards as a function of the congruency and valence of the card. A stronger self-attribution bias was observed for paranormal believers compared to skeptics and this bias was specifically related to traditional religious beliefs and belief in superstition. No relation between paranormal beliefs and illusory control was found. Self-report measures indicated that paranormal beliefs were associated to being raised in a spiritual family and to anomalous experiences during childhood. Thereby this study suggests that paranormal beliefs are related to specific cognitive biases that in turn are shaped by socio-cultural factors. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Exchange bias studied with polarized neutron reflectivity

    International Nuclear Information System (INIS)

    Velthuis, S. G. E. te

    2000-01-01

    The role of Polarized Neutron Reflectivity (PNR) for studying natural and synthetic exchange biased systems is illustrated. For a partially oxidized thin film of Co, cycling of the magnetic field causes a considerable reduction of the bias, which the onset of diffuse neutron scattering shows to be due to the loosening of the ferromagnetic domains. On the other hand, PNR measurements of a model exchange bias junction consisting of an n-layered Fe/Cr antiferromagnetic (AF) superlattice coupled with an m-layered Fe/Cr ferromagnetic (F) superlattice confirm the predicted collinear magnetization in the two superlattices. The two magnetized states of the F (along or opposite to the bias field) differ only in the relative orientation of the F and adjacent AF layer. The possibility of reading clearly the magnetic state at the interface pinpoints the commanding role that PNR is having in solving this intriguing problem

  20. Predictability of Conversation Partners

    Science.gov (United States)

    Takaguchi, Taro; Nakamura, Mitsuhiro; Sato, Nobuo; Yano, Kazuo; Masuda, Naoki

    2011-08-01

    Recent developments in sensing technologies have enabled us to examine the nature of human social behavior in greater detail. By applying an information-theoretic method to the spatiotemporal data of cell-phone locations, [C. Song , ScienceSCIEAS0036-8075 327, 1018 (2010)] found that human mobility patterns are remarkably predictable. Inspired by their work, we address a similar predictability question in a different kind of human social activity: conversation events. The predictability in the sequence of one’s conversation partners is defined as the degree to which one’s next conversation partner can be predicted given the current partner. We quantify this predictability by using the mutual information. We examine the predictability of conversation events for each individual using the longitudinal data of face-to-face interactions collected from two company offices in Japan. Each subject wears a name tag equipped with an infrared sensor node, and conversation events are marked when signals are exchanged between sensor nodes in close proximity. We find that the conversation events are predictable to a certain extent; knowing the current partner decreases the uncertainty about the next partner by 28.4% on average. Much of the predictability is explained by long-tailed distributions of interevent intervals. However, a predictability also exists in the data, apart from the contribution of their long-tailed nature. In addition, an individual’s predictability is correlated with the position of the individual in the static social network derived from the data. Individuals confined in a community—in the sense of an abundance of surrounding triangles—tend to have low predictability, and those bridging different communities tend to have high predictability.

  1. Predictability of Conversation Partners

    Directory of Open Access Journals (Sweden)

    Taro Takaguchi

    2011-09-01

    Full Text Available Recent developments in sensing technologies have enabled us to examine the nature of human social behavior in greater detail. By applying an information-theoretic method to the spatiotemporal data of cell-phone locations, [C. Song et al., Science 327, 1018 (2010SCIEAS0036-8075] found that human mobility patterns are remarkably predictable. Inspired by their work, we address a similar predictability question in a different kind of human social activity: conversation events. The predictability in the sequence of one’s conversation partners is defined as the degree to which one’s next conversation partner can be predicted given the current partner. We quantify this predictability by using the mutual information. We examine the predictability of conversation events for each individual using the longitudinal data of face-to-face interactions collected from two company offices in Japan. Each subject wears a name tag equipped with an infrared sensor node, and conversation events are marked when signals are exchanged between sensor nodes in close proximity. We find that the conversation events are predictable to a certain extent; knowing the current partner decreases the uncertainty about the next partner by 28.4% on average. Much of the predictability is explained by long-tailed distributions of interevent intervals. However, a predictability also exists in the data, apart from the contribution of their long-tailed nature. In addition, an individual’s predictability is correlated with the position of the individual in the static social network derived from the data. Individuals confined in a community—in the sense of an abundance of surrounding triangles—tend to have low predictability, and those bridging different communities tend to have high predictability.

  2. The source of the truth bias: Heuristic processing?

    Science.gov (United States)

    Street, Chris N H; Masip, Jaume

    2015-06-01

    People believe others are telling the truth more often than they actually are; this is called the truth bias. Surprisingly, when a speaker is judged at multiple points across their statement the truth bias declines. Previous claims argue this is evidence of a shift from (biased) heuristic processing to (reasoned) analytical processing. In four experiments we contrast the heuristic-analytic model (HAM) with alternative accounts. In Experiment 1, the decrease in truth responding was not the result of speakers appearing more deceptive, but was instead attributable to the rater's processing style. Yet contrary to HAMs, across three experiments we found the decline in bias was not related to the amount of processing time available (Experiments 1-3) or the communication channel (Experiment 2). In Experiment 4 we found support for a new account: that the bias reflects whether raters perceive the statement to be internally consistent. © 2015 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  3. A method for additive bias correction in cross-cultural surveys

    DEFF Research Database (Denmark)

    Scholderer, Joachim; Grunert, Klaus G.; Brunsø, Karen

    2001-01-01

    additive bias from cross-cultural data. The procedure involves four steps: (1) embed a potentially biased item in a factor-analytic measurement model, (2) test for the existence of additive bias between populations, (3) use the factor-analytic model to estimate the magnitude of the bias, and (4) replace......Measurement bias in cross-cultural surveys can seriously threaten the validity of hypothesis tests. Direct comparisons of means depend on the assumption that differences in observed variables reflect differences in the underlying constructs, and not an additive bias that may be caused by cultural...... differences in the understanding of item wording or response category labels. However, experience suggests that additive bias can be found more often than not. Based on the concept of partial measurement invariance (Byrne, Shavelson and Muthén, 1989), the present paper develops a procedure for eliminating...

  4. On the Borders of Harmful and Helpful Beauty Biases

    Directory of Open Access Journals (Sweden)

    Maria Agthe

    2016-06-01

    Full Text Available Research with European Caucasian samples demonstrates that attractiveness-based biases in social evaluation depend on the constellation of the sex of the evaluator and the sex of the target: Whereas people generally show positive biases toward attractive opposite-sex persons, they show less positive or even negative biases toward attractive same-sex persons. By examining these biases both within and between different ethnicities, the current studies provide new evidence for both the generalizability and the specificity of these attractiveness-based social perception biases. Examining within-ethnicity effects, Study 1 is the first to demonstrate that samples from diverse ethnic backgrounds parallel the finding of European Caucasian samples: The advantageous or adverse effects of attractiveness depend on the gender constellation of the evaluator and the evaluated person. Examining between-ethnicity effects, Study 2 found that these attractiveness-based biases emerge almost exclusively toward targets of the evaluator’s own ethnic background; these biases were reduced or eliminated for cross-ethnicity evaluations and interaction intentions. We discuss these findings in light of evolutionary principles and reflect on potential interactions between culture and evolved cognitive mechanisms.

  5. Biased Supervision

    OpenAIRE

    Josse Delfgaauw; Michiel Souverijn

    2014-01-01

    markdownabstract__Abstract__ When verifiable performance measures are imperfect, organizations often resort to subjective performance pay. This may give supervisors the power to direct employees towards tasks that mainly benefit the supervisor rather than the organization. We cast a principal-supervisor-agent model in a multitask setting, where the supervisor has an intrinsic preference towards specific tasks. We show that subjective performance pay based on evaluation by a biased supervisor ...

  6. Statistical thermodynamics foundation for photovoltaic and photothermal conversion. II. Application to photovoltaic conversion

    Science.gov (United States)

    Badescu, Viorel; Landsberg, Peter T.

    1995-08-01

    The general theory developed in part I was applied to build up two models of photovoltaic conversion. To this end two different systems were analyzed. The first system consists of the whole absorber (converter), for which the balance equations for energy and entropy are written and then used to derive an upper bound for solar energy conversion. The second system covers a part of the absorber (converter), namely the valence and conduction electronic bands. The balance of energy is used in this case to derive, under additional assumptions, another upper limit for the conversion efficiency. This second system deals with the real location where the power is generated. Both models take into consideration the radiation polarization and reflection, and the effects of concentration. The second model yields a more accurate upper bound for the conversion efficiency. A generalized solar cell equation is derived. It is proved that other previous theories are particular cases of the present more general formalism.

  7. Computer code conversion using HISTORIAN

    International Nuclear Information System (INIS)

    Matsumoto, Kiyoshi; Kumakura, Toshimasa.

    1990-09-01

    When a computer program written for a computer A is converted for a computer B, in general, the A version source program is rewritten for B version. However, in this way of program conversion, the following inconvenient problems arise. 1) The original statements to be rewritten for B version are lost. 2) If the original statements of the A version rewritten for B version would remain as comment lines, the B version source program becomes quite large. 3) When update directives of the program are mailed from the organization which developed the program or when some modifications are needed for the program, it is difficult to point out the part to be updated or modified in the B version source program. To solve these problems, the conversion method using the general-purpose software management aid system, HISTORIAN, has been introduced. This conversion method makes a large computer code a easy-to-use program for use to update, modify or improve after the conversion. This report describes the planning and procedures of the conversion method and the MELPROG-PWR/MOD1 code conversion from the CRAY version to the JAERI FACOM version as an example. This report would provide useful information for those who develop or introduce large programs. (author)

  8. Frequency conversion of structured light.

    Science.gov (United States)

    Steinlechner, Fabian; Hermosa, Nathaniel; Pruneri, Valerio; Torres, Juan P

    2016-02-15

    Coherent frequency conversion of structured light, i.e. the ability to manipulate the carrier frequency of a wave front without distorting its spatial phase and intensity profile, provides the opportunity for numerous novel applications in photonic technology and fundamental science. In particular, frequency conversion of spatial modes carrying orbital angular momentum can be exploited in sub-wavelength resolution nano-optics and coherent imaging at a wavelength different from that used to illuminate an object. Moreover, coherent frequency conversion will be crucial for interfacing information stored in the high-dimensional spatial structure of single and entangled photons with various constituents of quantum networks. In this work, we demonstrate frequency conversion of structured light from the near infrared (803 nm) to the visible (527 nm). The conversion scheme is based on sum-frequency generation in a periodically poled lithium niobate crystal pumped with a 1540-nm Gaussian beam. We observe frequency-converted fields that exhibit a high degree of similarity with the input field and verify the coherence of the frequency-conversion process via mode projection measurements with a phase mask and a single-mode fiber. Our results demonstrate the suitability of exploiting the technique for applications in quantum information processing and coherent imaging.

  9. Cognitive biases and decision making in gambling.

    Science.gov (United States)

    Chóliz, Mariano

    2010-08-01

    Heuristics and cognitive biases can occur in reasoning and decision making. Some of them are very common in gamblers (illusion of control, representativeness, availability, etc.). Structural characteristics and functioning of games of chance favor the appearance of these biases. Two experiments were conducted with nonpathological gamblers. The first experiment was a game of dice with wagers. In the second experiment, the participants played two bingo games. Specific rules of the games favored the appearance of cognitive bias (illusion of control) and heuristics (representativeness and availability) and influence on the bets. Results and implications for gambling are discussed.

  10. 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.

  11. Biasing vector network analyzers using variable frequency and amplitude signals

    Science.gov (United States)

    Nobles, J. E.; Zagorodnii, V.; Hutchison, A.; Celinski, Z.

    2016-08-01

    We report the development of a test setup designed to provide a variable frequency biasing signal to a vector network analyzer (VNA). The test setup is currently used for the testing of liquid crystal (LC) based devices in the microwave region. The use of an AC bias for LC based devices minimizes the negative effects associated with ionic impurities in the media encountered with DC biasing. The test setup utilizes bias tees on the VNA test station to inject the bias signal. The square wave biasing signal is variable from 0.5 to 36.0 V peak-to-peak (VPP) with a frequency range of DC to 10 kHz. The test setup protects the VNA from transient processes, voltage spikes, and high-frequency leakage. Additionally, the signals to the VNA are fused to ½ amp and clipped to a maximum of 36 VPP based on bias tee limitations. This setup allows us to measure S-parameters as a function of both the voltage and the frequency of the applied bias signal.

  12. Overcoming difficult conversations in clinical supervision

    Directory of Open Access Journals (Sweden)

    Williams B

    2016-06-01

    Full Text Available Brett Williams,1 Christine King,1 Tanya Edlington,21Department of Community Emergency Health and Paramedic Practice, Monash University, Franskton, VIC, 2The Conversation Clinic Pty Ltd, Melbourne, VIC, Australia Background: Clinical supervisors are responsible for managing many facets of clinical learning and face a range of challenges when the need for "difficult" conversations arises, including the need to manage conflict and relationships. Methods: Spotlight on Conversations Workshop was developed to improve the capacity of clinical supervisors to engage in difficult conversations. They were designed to challenge the mindset of clinical supervisors about difficult conversations with students, the consequences of avoiding difficult conversations, and to offer activities for practicing difficult conversations. Preworkshop, postworkshop, and 4-month follow-up evaluations assessed improvements in knowledge, intent to improve, and confidence along with workshop satisfaction. Results: Nine workshops were delivered in a range of locations across Victoria, Australia, involving a total of 117 clinical supervisors. Preworkshop evaluations illustrated that more than half of the participants had avoided up to two difficult conversations in the last month in their workplace. Postworkshop evaluation at 4 months showed very high levels of satisfaction with the workshop's relevancy, content, and training, as well as participants' intention to apply knowledge and skills. Also shown were significant changes in participants' confidence to have difficult conversations not only with students but also with other peers and colleagues. In follow-up in-depth interviews with 20 of the 117 participants, 75% said they had made definite changes in their practice because of what they learned in the workshop and another 10% said they would make changes to their practice, but had not had the opportunity yet to do so. Conclusion: We conclude that the Spotlight on

  13. Efficient bias correction for magnetic resonance image denoising.

    Science.gov (United States)

    Mukherjee, Partha Sarathi; Qiu, Peihua

    2013-05-30

    Magnetic resonance imaging (MRI) is a popular radiology technique that is used for visualizing detailed internal structure of the body. Observed MRI images are generated by the inverse Fourier transformation from received frequency signals of a magnetic resonance scanner system. Previous research has demonstrated that random noise involved in the observed MRI images can be described adequately by the so-called Rician noise model. Under that model, the observed image intensity at a given pixel is a nonlinear function of the true image intensity and of two independent zero-mean random variables with the same normal distribution. Because of such a complicated noise structure in the observed MRI images, denoised images by conventional denoising methods are usually biased, and the bias could reduce image contrast and negatively affect subsequent image analysis. Therefore, it is important to address the bias issue properly. To this end, several bias-correction procedures have been proposed in the literature. In this paper, we study the Rician noise model and the corresponding bias-correction problem systematically and propose a new and more effective bias-correction formula based on the regression analysis and Monte Carlo simulation. Numerical studies show that our proposed method works well in various applications. Copyright © 2012 John Wiley & Sons, Ltd.

  14. Paradoxical therapy in conversion disorder

    OpenAIRE

    ATAOĞLU, Ahmet

    1998-01-01

    Paradoxical therapy consists of suggesting that the patient intentionally engages in the unwanted behaviour, such as performing complusive ritual or bringing on a conversion attack. In this study paradoxical intention (PI) was used with to half of the patients with conversion disorders, while the other half were treated with diazepam in order to examine the efficiency of the PI versus diazepam in conversion disorder. Patients treated with PI appeared to have a greater improvement r...

  15. Corpus-based Transitivity Biases in Individuals with Aphasia

    Directory of Open Access Journals (Sweden)

    Gayle DeDe

    2015-04-01

    Full Text Available Introduction Spontaneous speech samples in individuals with aphasia (IWA have been analyzed to examine many different psycholinguistic features. The present study focused on how IWA use verbs in spontaneous speech. Some verbs can occur in more than one argument structure, but are biased to occur more frequently in one frame than another. For example, "watch" appears in transitive and intransitive structures, but is usually used transitively. This is known as a transitivity bias. It is unknown whether IWA show the same transitivity biases in production as those reported in previous corpus studies with unimpaired individuals. Studies of sentence comprehension have shown that IWA are sensitive to verb biases (e.g., DeDe, 2013. In addition, IWA have shown an overall preference for transitive structures, which are the most frequent structures in English (Roland, Dick, & Elman, 2007. The present study investigated whether IWA show the same pattern of transitive and intransitive biases in spontaneous speech as unimpaired individuals. Method Participants: 278 interviews with IWA were taken from AphasiaBank. The IWA represented a range of aphasia types. Participants were omitted if they spoke English as a second language. Materials: 54 verbs were coded. We chose verbs with the goal of representing different bias types (e.g., transitive, intransitive, sentential complement. Of these, data from 11 transitively biased and 11 intransitively biased verbs (matched for frequency of use and number of syllables are presented here. Coding: All productions of the 54 verbs were coded. The coding protocol was based on Gahl, Jurafsky, and Roland (2004. We implemented an additional level of coding to indicate erroneous verb productions, such as ungrammatical structures and verb agreement errors. Results The (intransitivity biases for IWA were compared to biases from a previously published corpus study (Gahl et al., 2004. The IWA used transitively biased verbs in

  16. Pseudomonas aeruginosa chromosomal beta-lactamase in patients with cystic fibrosis and chronic lung infection. Mechanism of antibiotic resistance and target of the humoral immune response

    DEFF Research Database (Denmark)

    Ciofu, Oana

    2003-01-01

    the development of resistance to beta-lactam antibiotics and the occurrence of high beta-lactamase producing strains and between the MIC of the beta-lactams and the levels of beta-lactamase expression. Partially derepressed mutants, characterized by high basal levels of beta-lactamase with the possibility...... of induction to even higher levels during treatment with beta-lactam antibiotics, were the most frequent phenotype found among resistant Danish P. aeruginosa CF isolates. We have also shown that the high alginate producing P. aeruginosa isolates, that characterize the chronic lung infection in CF patients......, are more susceptible to antibiotics and produce less beta-lactamase than the non-mucoid paired isolates. We propose that the non-mucoid isolates are exposed to a relatively higher antibiotic pressure than the mucoid isolates and therefore, they become easily antibiotic resistant and in consequence produce...

  17. A Principal Components Analysis of Dynamic Spatial Memory Biases

    Science.gov (United States)

    Motes, Michael A.; Hubbard, Timothy L.; Courtney, Jon R.; Rypma, Bart

    2008-01-01

    Research has shown that spatial memory for moving targets is often biased in the direction of implied momentum and implied gravity, suggesting that representations of the subjective experiences of these physical principles contribute to such biases. The present study examined the association between these spatial memory biases. Observers viewed…

  18. Bias correction of daily satellite precipitation data using genetic algorithm

    Science.gov (United States)

    Pratama, A. W.; Buono, A.; Hidayat, R.; Harsa, H.

    2018-05-01

    Climate Hazards Group InfraRed Precipitation with Stations (CHIRPS) was producted by blending Satellite-only Climate Hazards Group InfraRed Precipitation (CHIRP) with Stasion observations data. The blending process was aimed to reduce bias of CHIRP. However, Biases of CHIRPS on statistical moment and quantil values were high during wet season over Java Island. This paper presented a bias correction scheme to adjust statistical moment of CHIRP using observation precipitation data. The scheme combined Genetic Algorithm and Nonlinear Power Transformation, the results was evaluated based on different season and different elevation level. The experiment results revealed that the scheme robustly reduced bias on variance around 100% reduction and leaded to reduction of first, and second quantile biases. However, bias on third quantile only reduced during dry months. Based on different level of elevation, the performance of bias correction process is only significantly different on skewness indicators.

  19. Microwave plasma mode conversion

    International Nuclear Information System (INIS)

    Torres, H.S.; Sakanaka, P.H.; Villarroel, C.H.

    1985-01-01

    The behavior of hot electrons during the process of laser-produced plasma is studied. The basic equations of mode conversion from electromagnetic waves to electrostatic waves are presented. It is shown by mode conversion, that, the resonant absorption and parametric instabilities appear simultaneously, but in different plasma regions. (M.C.K.) [pt

  20. A pupillary index of susceptibility to decision biases

    OpenAIRE

    Eldar, Eran; Felso, Valkyrie; Cohen, Jonathan; Niv, Yael

    2018-01-01

    Under what conditions do humans systematically deviate from rational decision making? Here we show that pupillary indices of low neural gain are associated with strong and consistent biases across six different extensively-studied decision making tasks, whereas indices of high gain are associated with weak or absent biases. Lower susceptibility to biases, however, comes at the cost of indecisiveness, or alternatively, prolonged deliberation time. We explain the association between low gain an...

  1. Conversing as Metaphor of Human Thinking: Is Mind like a Conversation?

    Science.gov (United States)

    Sorsana, Christine; Trognon, Alain

    2018-06-01

    How can researchers shape their ideas so that they understand the mind better? This theoretical paper discusses the merits of the conversation metaphor as a means of analyzing the human mind. We will develop arguments concerning conversation as i) a situated and distributed activity, ii) a "product" in perpetual construction, and iii) the amount of credence and belief we afford it. Finally, we will advocate for metaphorical tools that promote a more dynamic conceptualization of human thinking.

  2. Assessing Projection Bias in Consumers' Food Preferences.

    Directory of Open Access Journals (Sweden)

    Tiziana de-Magistris

    Full Text Available The aim of this study is to test whether projection bias exists in consumers' purchasing decisions for food products. To achieve our aim, we used a non-hypothetical experiment (i.e., experimental auction, where hungry and non-hungry participants were incentivized to reveal their willingness to pay (WTP. The results confirm the existence of projection bias when consumers made their decisions on food products. In particular, projection bias existed because currently hungry participants were willing to pay a higher price premium for cheeses than satiated ones, both in hungry and satiated future states. Moreover, participants overvalued the food product more when they were delivered in the future hungry condition than in the satiated one. Our study provides clear, quantitative and meaningful evidence of projection bias because our findings are based on economic valuation of food preferences. Indeed, the strength of this study is that findings are expressed in terms of willingness to pay which is an interpretable amount of money.

  3. Biased Monte Carlo optimization: the basic approach

    International Nuclear Information System (INIS)

    Campioni, Luca; Scardovelli, Ruben; Vestrucci, Paolo

    2005-01-01

    It is well-known that the Monte Carlo method is very successful in tackling several kinds of system simulations. It often happens that one has to deal with rare events, and the use of a variance reduction technique is almost mandatory, in order to have Monte Carlo efficient applications. The main issue associated with variance reduction techniques is related to the choice of the value of the biasing parameter. Actually, this task is typically left to the experience of the Monte Carlo user, who has to make many attempts before achieving an advantageous biasing. A valuable result is provided: a methodology and a practical rule addressed to establish an a priori guidance for the choice of the optimal value of the biasing parameter. This result, which has been obtained for a single component system, has the notable property of being valid for any multicomponent system. In particular, in this paper, the exponential and the uniform biases of exponentially distributed phenomena are investigated thoroughly

  4. A machine learning model with human cognitive biases capable of learning from small and biased datasets.

    Science.gov (United States)

    Taniguchi, Hidetaka; Sato, Hiroshi; Shirakawa, Tomohiro

    2018-05-09

    Human learners can generalize a new concept from a small number of samples. In contrast, conventional machine learning methods require large amounts of data to address the same types of problems. Humans have cognitive biases that promote fast learning. Here, we developed a method to reduce the gap between human beings and machines in this type of inference by utilizing cognitive biases. We implemented a human cognitive model into machine learning algorithms and compared their performance with the currently most popular methods, naïve Bayes, support vector machine, neural networks, logistic regression and random forests. We focused on the task of spam classification, which has been studied for a long time in the field of machine learning and often requires a large amount of data to obtain high accuracy. Our models achieved superior performance with small and biased samples in comparison with other representative machine learning methods.

  5. A father effect explains sex-ratio bias.

    Science.gov (United States)

    Malo, Aurelio F; Martinez-Pastor, Felipe; Garcia-Gonzalez, Francisco; Garde, Julián; Ballou, Jonathan D; Lacy, Robert C

    2017-08-30

    Sex ratio allocation has important fitness consequences, and theory predicts that parents should adjust offspring sex ratio in cases where the fitness returns of producing male and female offspring vary. The ability of fathers to bias offspring sex ratios has traditionally been dismissed given the expectation of an equal proportion of X- and Y-chromosome-bearing sperm (CBS) in ejaculates due to segregation of sex chromosomes at meiosis. This expectation has been recently refuted. Here we used Peromyscus leucopus to demonstrate that sex ratio is explained by an exclusive effect of the father, and suggest a likely mechanism by which male-driven sex-ratio bias is attained. We identified a male sperm morphological marker that is associated with the mechanism leading to sex ratio bias; differences among males in the sperm nucleus area (a proxy for the sex chromosome that the sperm contains) explain 22% variation in litter sex ratio. We further show the role played by the sperm nucleus area as a mediator in the relationship between individual genetic variation and sex-ratio bias. Fathers with high levels of genetic variation had ejaculates with a higher proportion of sperm with small nuclei area. This, in turn, led to siring a higher proportion of sons (25% increase in sons per 0.1 decrease in the inbreeding coefficient). Our results reveal a plausible mechanism underlying unexplored male-driven sex-ratio biases. We also discuss why this pattern of paternal bias can be adaptive. This research puts to rest the idea that father contribution to sex ratio variation should be disregarded in vertebrates, and will stimulate research on evolutionary constraints to sex ratios-for example, whether fathers and mothers have divergent, coinciding, or neutral sex allocation interests. Finally, these results offer a potential explanation for those intriguing cases in which there are sex ratio biases, such as in humans. © 2017 The Author(s).

  6. A New Source Biasing Approach in ADVANTG

    International Nuclear Information System (INIS)

    Bevill, Aaron M.; Mosher, Scott W.

    2012-01-01

    The ADVANTG code has been developed at Oak Ridge National Laboratory to generate biased sources and weight window maps for MCNP using the CADIS and FW-CADIS methods. In preparation for an upcoming RSICC release, a new approach for generating a biased source has been developed. This improvement streamlines user input and improves reliability. Previous versions of ADVANTG generated the biased source from ADVANTG input, writing an entirely new general fixed-source definition (SDEF). Because volumetric sources were translated into SDEF-format as a finite set of points, the user had to perform a convergence study to determine whether the number of source points used accurately represented the source region. Further, the large number of points that must be written in SDEF-format made the MCNP input and output files excessively long and difficult to debug. ADVANTG now reads SDEF-format distributions and generates corresponding source biasing cards, eliminating the need for a convergence study. Many problems of interest use complicated source regions that are defined using cell rejection. In cell rejection, the source distribution in space is defined using an arbitrarily complex cell and a simple bounding region. Source positions are sampled within the bounding region but accepted only if they fall within the cell; otherwise, the position is resampled entirely. When biasing in space is applied to sources that use rejection sampling, current versions of MCNP do not account for the rejection in setting the source weight of histories, resulting in an 'unfair game'. This problem was circumvented in previous versions of ADVANTG by translating volumetric sources into a finite set of points, which does not alter the mean history weight ((bar w)). To use biasing parameters without otherwise modifying the original cell-rejection SDEF-format source, ADVANTG users now apply a correction factor for (bar w) in post-processing. A stratified-random sampling approach in ADVANTG is under

  7. Significant biases affecting abundance determinations

    Science.gov (United States)

    Wesson, Roger

    2015-08-01

    I have developed two highly efficient codes to automate analyses of emission line nebulae. The tools place particular emphasis on the propagation of uncertainties. The first tool, ALFA, uses a genetic algorithm to rapidly optimise the parameters of gaussian fits to line profiles. It can fit emission line spectra of arbitrary resolution, wavelength range and depth, with no user input at all. It is well suited to highly multiplexed spectroscopy such as that now being carried out with instruments such as MUSE at the VLT. The second tool, NEAT, carries out a full analysis of emission line fluxes, robustly propagating uncertainties using a Monte Carlo technique.Using these tools, I have found that considerable biases can be introduced into abundance determinations if the uncertainty distribution of emission lines is not well characterised. For weak lines, normally distributed uncertainties are generally assumed, though it is incorrect to do so, and significant biases can result. I discuss observational evidence of these biases. The two new codes contain routines to correctly characterise the probability distributions, giving more reliable results in analyses of emission line nebulae.

  8. The Local Bias of Individual Investors

    OpenAIRE

    Ning Zhu

    2002-01-01

    This study investigates individual investors' bias towards nearby companies. Using data from a large U.S. discount brokerage, we find that individual investors tend to invest in companies closer to them relative to the market portfolio. Unlike Coval and Moskowitz's (1999) findings on institutional investors, however, we find that advantageous information cannot explain individual investors' local bias. Accounting numbers and information asymmetry matter less to individual investors' local bia...

  9. Conversational Styles and Misunderstanding in Cross-Sex Conversations in He’s Just Not That into You Movie

    OpenAIRE

    Ayu Nyoman Aryani

    2017-01-01

    Conversation is a social interaction among societies. In this case, gender differences in daily communication lead to men’s and women’s different point of views in performing styles of the conversations. Misunderstanding is likely to occur in crosssex conversations when the idea or thought are understood differently by men and women. This study was intended to analyze the use of conversational styles by men and women and also investigate the misunderstanding phenomena that happened in cross-s...

  10. Conversational evidence in therapeutic dialogue.

    Science.gov (United States)

    Strong, Tom; Busch, Robbie; Couture, Shari

    2008-07-01

    Family therapists' participation in therapeutic dialogue with clients is typically informed by evidence of how such dialogue is developing. In this article, we propose that conversational evidence, the kind that can be empirically analyzed using discourse analyses, be considered a contribution to widening psychotherapy's evidence base. After some preliminaries about what we mean by conversational evidence, we provide a genealogy of evaluative practice in psychotherapy, and examine qualitative evaluation methods for their theoretical compatibilities with social constructionist approaches to family therapy. We then move on to examine the notion of accomplishment in therapeutic dialogue given how such accomplishments can be evaluated using conversation analysis. We conclude by considering a number of research and pedagogical implications we associate with conversational evidence.

  11. Effective communication during difficult conversations.

    Science.gov (United States)

    Polito, Jacquelyn M

    2013-06-01

    A strong interest and need exist in the workplace today to master the skills of conducting difficult conversations. Theories and strategies abound, yet none seem to have found the magic formula with universal appeal and success. If it is such an uncomfortable skill to master is it better to avoid or initiate such conversations with employees? Best practices and evidence-based management guide us to the decision that quality improvement dictates effective communication, even when difficult. This brief paper will offer some suggestions for strategies to manage difficult conversations with employees. Mastering the skills of conducting difficult conversations is clearly important to keeping lines of communication open and productive. Successful communication skills may actually help to avert confrontation through employee engagement, commitment and appropriate corresponding behavior

  12. 5 CFR 536.303 - Geographic conversion.

    Science.gov (United States)

    2010-01-01

    ... after geographic conversion is the employee's existing payable rate of basic pay in effect immediately before the action. (b) Geographic conversion when a retained rate employee's official worksite is changed... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Geographic conversion. 536.303 Section...

  13. Design of a Novel Voltage Controller for Conversion of Carbon Dioxide into Clean Fuels Using the Integration of a Vanadium Redox Battery with Solar Energy

    Directory of Open Access Journals (Sweden)

    Ting-Chia Ou

    2018-02-01

    Full Text Available This letter presents a design for a novel voltage controller (NVC which can exhibit three different reactions using the integration of a vanadium redox battery (VRB with solar energy, and uses only electrochemical potentials with optimal external bias voltage control to carry out hydrogen production and the conversion of carbon dioxide (CO2 into methane and methanol. This NVC is simply constructed by using dynamic switch and control strategies with a time-variant control system. In this design, the interval voltage bias solutions obtained by the proposed NVC exhibit better voltage ranges and good agreement with the practical scenarios, which will bring significant benefits to operation for continuous reduction of CO2 into value-added clean fuels using the integration of a VRB with solar energy or any other renewable energy resource for future applications.

  14. Reporting bias in medical research - a narrative review

    Directory of Open Access Journals (Sweden)

    Kölsch Heike

    2010-04-01

    Full Text Available Abstract Reporting bias represents a major problem in the assessment of health care interventions. Several prominent cases have been described in the literature, for example, in the reporting of trials of antidepressants, Class I anti-arrhythmic drugs, and selective COX-2 inhibitors. The aim of this narrative review is to gain an overview of reporting bias in the medical literature, focussing on publication bias and selective outcome reporting. We explore whether these types of bias have been shown in areas beyond the well-known cases noted above, in order to gain an impression of how widespread the problem is. For this purpose, we screened relevant articles on reporting bias that had previously been obtained by the German Institute for Quality and Efficiency in Health Care in the context of its health technology assessment reports and other research work, together with the reference lists of these articles. We identified reporting bias in 40 indications comprising around 50 different pharmacological, surgical (e.g. vacuum-assisted closure therapy, diagnostic (e.g. ultrasound, and preventive (e.g. cancer vaccines interventions. Regarding pharmacological interventions, cases of reporting bias were, for example, identified in the treatment of the following conditions: depression, bipolar disorder, schizophrenia, anxiety disorder, attention-deficit hyperactivity disorder, Alzheimer's disease, pain, migraine, cardiovascular disease, gastric ulcers, irritable bowel syndrome, urinary incontinence, atopic dermatitis, diabetes mellitus type 2, hypercholesterolaemia, thyroid disorders, menopausal symptoms, various types of cancer (e.g. ovarian cancer and melanoma, various types of infections (e.g. HIV, influenza and Hepatitis B, and acute trauma. Many cases involved the withholding of study data by manufacturers and regulatory agencies or the active attempt by manufacturers to suppress publication. The ascertained effects of reporting bias included the

  15. Bias-dependent hybrid PKI empirical-neural model of microwave FETs

    Science.gov (United States)

    Marinković, Zlatica; Pronić-Rančić, Olivera; Marković, Vera

    2011-10-01

    Empirical models of microwave transistors based on an equivalent circuit are valid for only one bias point. Bias-dependent analysis requires repeated extractions of the model parameters for each bias point. In order to make model bias-dependent, a new hybrid empirical-neural model of microwave field-effect transistors is proposed in this article. The model is a combination of an equivalent circuit model including noise developed for one bias point and two prior knowledge input artificial neural networks (PKI ANNs) aimed at introducing bias dependency of scattering (S) and noise parameters, respectively. The prior knowledge of the proposed ANNs involves the values of the S- and noise parameters obtained by the empirical model. The proposed hybrid model is valid in the whole range of bias conditions. Moreover, the proposed model provides better accuracy than the empirical model, which is illustrated by an appropriate modelling example of a pseudomorphic high-electron mobility transistor device.

  16. 24 CFR 972.109 - Conversion of developments.

    Science.gov (United States)

    2010-04-01

    ... writing whether it has approved the conversion plan. Units that are vacant or vacated on or after the... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Conversion of developments. 972.109... DEVELOPMENT CONVERSION OF PUBLIC HOUSING TO TENANT-BASED ASSISTANCE Required Conversion of Public Housing...

  17. Reassessing biases and other uncertainties in sea surface temperature observations measured in situ since 1850: 2. Biases and homogenization

    Science.gov (United States)

    Kennedy, J. J.; Rayner, N. A.; Smith, R. O.; Parker, D. E.; Saunby, M.

    2011-07-01

    Changes in instrumentation and data availability have caused time-varying biases in estimates of global and regional average sea surface temperature. The size of the biases arising from these changes are estimated and their uncertainties evaluated. The estimated biases and their associated uncertainties are largest during the period immediately following the Second World War, reflecting the rapid and incompletely documented changes in shipping and data availability at the time. Adjustments have been applied to reduce these effects in gridded data sets of sea surface temperature and the results are presented as a set of interchangeable realizations. Uncertainties of estimated trends in global and regional average sea surface temperature due to bias adjustments since the Second World War are found to be larger than uncertainties arising from the choice of analysis technique, indicating that this is an important source of uncertainty in analyses of historical sea surface temperatures. Despite this, trends over the twentieth century remain qualitatively consistent.

  18. [Management of patients with conversion disorder].

    Science.gov (United States)

    Vermeulen, Marinus; Hoekstra, Jan; Kuipers-van Kooten, Mariëtte J; van der Linden, Els A M

    2014-01-01

    The symptoms of conversion disorder are not due to conscious simulation. There should be no doubt that the symptoms of conversion disorder are genuine, even if scans do not reveal any abnormalities. The management of patients with conversion disorder starts with an explanation of the diagnosis. The essence of this explanation is that patients first hear about what the diagnosis actually means and only after this about what they do not have. When explaining the diagnosis it is a good idea to use metaphors. The treatment of patients with conversion disorder is carried out together with a physical therapist. The collaboration of healthcare professionals who are involved in the treatment of a patient with conversion disorder should preferably be coordinated by the patient's general practitioner.

  19. Attentional bias for positive emotional stimuli: A meta-analytic investigation.

    Science.gov (United States)

    Pool, Eva; Brosch, Tobias; Delplanque, Sylvain; Sander, David

    2016-01-01

    Despite an initial focus on negative threatening stimuli, researchers have more recently expanded the investigation of attentional biases toward positive rewarding stimuli. The present meta-analysis systematically compared attentional bias for positive compared with neutral visual stimuli across 243 studies (N = 9,120 healthy participants) that used different types of attentional paradigms and positive stimuli. Factors were tested that, as postulated by several attentional models derived from theories of emotion, might modulate this bias. Overall, results showed a significant, albeit modest (Hedges' g = .258), attentional bias for positive as compared with neutral stimuli. Moderator analyses revealed that the magnitude of this attentional bias varied as a function of arousal and that this bias was significantly larger when the emotional stimulus was relevant to specific concerns (e.g., hunger) of the participants compared with other positive stimuli that were less relevant to the participants' concerns. Moreover, the moderator analyses showed that attentional bias for positive stimuli was larger in paradigms that measure early, rather than late, attentional processing, suggesting that attentional bias for positive stimuli occurs rapidly and involuntarily. Implications for theories of emotion and attention are discussed. (c) 2015 APA, all rights reserved).

  20. On the Limitations of Variational Bias Correction

    Science.gov (United States)

    Moradi, Isaac; Mccarty, Will; Gelaro, Ronald

    2018-01-01

    Satellite radiances are the largest dataset assimilated into Numerical Weather Prediction (NWP) models, however the data are subject to errors and uncertainties that need to be accounted for before assimilating into the NWP models. Variational bias correction uses the time series of observation minus background to estimate the observations bias. This technique does not distinguish between the background error, forward operator error, and observations error so that all these errors are summed up together and counted as observation error. We identify some sources of observations errors (e.g., antenna emissivity, non-linearity in the calibration, and antenna pattern) and show the limitations of variational bias corrections on estimating these errors.

  1. Energy conversion alternatives study

    Science.gov (United States)

    Shure, L. T.

    1979-01-01

    Comparison of coal based energy systems is given. Study identifies and compares various advanced energy conversion systems using coal or coal derived fuels for baselaoad electric power generation. Energy Conversion Alternatives Study (ECAS) reports provede government, industry, and general public with technically consistent basis for comparison of system's options of interest for fossilfired electric-utility application.

  2. Assessing atmospheric bias correction for dynamical consistency using potential vorticity

    International Nuclear Information System (INIS)

    Rocheta, Eytan; Sharma, Ashish; Evans, Jason P

    2014-01-01

    Correcting biases in atmospheric variables prior to impact studies or dynamical downscaling can lead to new biases as dynamical consistency between the ‘corrected’ fields is not maintained. Use of these bias corrected fields for subsequent impact studies and dynamical downscaling provides input conditions that do not appropriately represent intervariable relationships in atmospheric fields. Here we investigate the consequences of the lack of dynamical consistency in bias correction using a measure of model consistency—the potential vorticity (PV). This paper presents an assessment of the biases present in PV using two alternative correction techniques—an approach where bias correction is performed individually on each atmospheric variable, thereby ignoring the physical relationships that exists between the multiple variables that are corrected, and a second approach where bias correction is performed directly on the PV field, thereby keeping the system dynamically coherent throughout the correction process. In this paper we show that bias correcting variables independently results in increased errors above the tropopause in the mean and standard deviation of the PV field, which are improved when using the alternative proposed. Furthermore, patterns of spatial variability are improved over nearly all vertical levels when applying the alternative approach. Results point to a need for a dynamically consistent atmospheric bias correction technique which results in fields that can be used as dynamically consistent lateral boundaries in follow-up downscaling applications. (letter)

  3. Systematic approach to establishing criticality biases

    International Nuclear Information System (INIS)

    Larson, S.L.

    1995-09-01

    A systematic approach has been developed to determine benchmark biases and apply those biases to code results to meet the requirements of DOE Order 5480.24 regarding documenting criticality safety margins. Previously, validation of the code against experimental benchmarks to prove reasonable agreement was sufficient. However, DOE Order 5480.24 requires contractors to adhere to the requirements of ANSI/ANS-8.1 and establish subcritical margins. A method was developed to incorporate biases and uncertainties from benchmark calculations into a k eff value with quantifiable uncertainty. The method produces a 95% confidence level in both the k eff value of the scenario modeled and the distribution of the k eff S calculated by the Monte Carlo code. Application of the method to a group of benchmarks modeled using the KENO-Va code and the SCALE 27 group cross sections is also presented

  4. Bounding the bias of contrastive divergence learning

    DEFF Research Database (Denmark)

    Fischer, Anja; Igel, Christian

    2011-01-01

    Optimization based on k-step contrastive divergence (CD) has become a common way to train restricted Boltzmann machines (RBMs). The k-step CD is a biased estimator of the log-likelihood gradient relying on Gibbs sampling. We derive a new upper bound for this bias. Its magnitude depends on k...

  5. Biased limiter experiments on text

    International Nuclear Information System (INIS)

    Phillips, P.E.; Wootton, A.J.; Rowan, W.L.; Ritz, C.P.; Rhodes, T.L.; Bengtson, R.D.; Hodge, W.L.; Durst, R.D.; McCool, S.C.; Richards, B.; Gentle, K.W.; Schoch, P.; Forster, J.C.; Hickok, R.L.; Evans, T.E.

    1987-01-01

    Experiments using an electrically biased limiter have been performed on the Texas Experimental Tokamak (TEXT). A small movable limiter is inserted past the main poloidal ring limiter (which is electrically connected to the vacuum vessel) and biased at V Lim with respect to it. The floating potential, plasma potential and shear layer position can be controlled. With vertical strokeV Lim vertical stroke ≥ 50 V the plasma density increases. For V Lim Lim > 0 the results obtained are inconclusive. Variation of V Lim changes the electrostatic turbulence which may explain the observed total flux changes. (orig.)

  6. Altering attentional control settings causes persistent biases of visual attention.

    Science.gov (United States)

    Knight, Helen C; Smith, Daniel T; Knight, David C; Ellison, Amanda

    2016-01-01

    Attentional control settings have an important role in guiding visual behaviour. Previous work within cognitive psychology has found that the deployment of general attentional control settings can be modulated by training. However, research has not yet established whether long-term modifications of one particular type of attentional control setting can be induced. To address this, we investigated persistent alterations to feature search mode, also known as an attentional bias, towards an arbitrary stimulus in healthy participants. Subjects were biased towards the colour green by an information sheet. Attentional bias was assessed using a change detection task. After an interval of either 1 or 2 weeks, participants were then retested on the same change detection task, tested on a different change detection task where colour was irrelevant, or were biased towards an alternative colour. One experiment included trials in which the distractor stimuli (but never the target stimuli) were green. The key finding was that green stimuli in the second task attracted attention, despite this impairing task performance. Furthermore, inducing a second attentional bias did not override the initial bias toward green objects. The attentional bias also persisted for at least two weeks. It is argued that this persistent attentional bias is mediated by a chronic change to participants' attentional control settings, which is aided by long-term representations involving contextual cueing. We speculate that similar changes to attentional control settings and continuous cueing may relate to attentional biases observed in psychopathologies. Targeting these biases may be a productive approach to treatment.

  7. Analysis of internal conversion coefficients

    International Nuclear Information System (INIS)

    Coursol, N.; Gorozhankin, V.M.; Yakushev, E.A.; Briancon, C.; Vylov, Ts.

    2000-01-01

    An extensive database has been assembled that contains the three most widely used sets of calculated internal conversion coefficients (ICC): [Hager R.S., Seltzer E.C., 1968. Internal conversion tables. K-, L-, M-shell Conversion coefficients for Z=30 to Z=103, Nucl. Data Tables A4, 1-237; Band I.M., Trzhaskovskaya M.B., 1978. Tables of gamma-ray internal conversion coefficients for the K-, L- and M-shells, 10≤Z≤104, Special Report of Leningrad Nuclear Physics Institute; Roesel F., Fries H.M., Alder K., Pauli H.C., 1978. Internal conversion coefficients for all atomic shells, At. Data Nucl. Data Tables 21, 91-289] and also includes new Dirac-Fock calculations [Band I.M. and Trzhaskovskaya M.B., 1993. Internal conversion coefficients for low-energy nuclear transitions, At. Data Nucl. Data Tables 55, 43-61]. This database is linked to a computer program to plot ICCs and their combinations (sums and ratios) as a function of Z and energy, as well as relative deviations of ICC or their combinations for any pair of tabulated data. Examples of these analyses are presented for the K-shell and total ICCs of the gamma-ray standards [Hansen H.H., 1985. Evaluation of K-shell and total internal conversion coefficients for some selected nuclear transitions, Eur. Appl. Res. Rept. Nucl. Sci. Tech. 11.6 (4) 777-816] and for the K-shell and total ICCs of high multipolarity transitions (total, K-, L-, M-shells of E3 and M3 and K-shell of M4). Experimental data sets are also compared with the theoretical values of these specific calculations

  8. Impact of Continued Biased Disenrollment from the Medic...

    Data.gov (United States)

    U.S. Department of Health & Human Services — Impact of Continued Biased Disenrollment from the Medicare Advantage Program to Fee-for-Service As reported in Impact of Continued Biased Disenrollment from the...

  9. Whiteliness and Institutional Racism: Hiding behind (Un)Conscious Bias

    Science.gov (United States)

    Tate, Shirley Anne; Page, Damien

    2018-01-01

    'Unconscious bias happens by our brains making incredibly quick judgements and assessments without us realising. Biases are influenced by background, cultural environment and experiences and we may not be aware of these views and opinions, or of their full impact and implications. This article opposes this point of view by arguing that bias is not…

  10. Evaluation of Bias Correction Method for Satellite-Based Rainfall Data

    Science.gov (United States)

    Bhatti, Haris Akram; Rientjes, Tom; Haile, Alemseged Tamiru; Habib, Emad; Verhoef, Wouter

    2016-01-01

    With the advances in remote sensing technology, satellite-based rainfall estimates are gaining attraction in the field of hydrology, particularly in rainfall-runoff modeling. Since estimates are affected by errors correction is required. In this study, we tested the high resolution National Oceanic and Atmospheric Administration’s (NOAA) Climate Prediction Centre (CPC) morphing technique (CMORPH) satellite rainfall product (CMORPH) in the Gilgel Abbey catchment, Ethiopia. CMORPH data at 8 km-30 min resolution is aggregated to daily to match in-situ observations for the period 2003–2010. Study objectives are to assess bias of the satellite estimates, to identify optimum window size for application of bias correction and to test effectiveness of bias correction. Bias correction factors are calculated for moving window (MW) sizes and for sequential windows (SW’s) of 3, 5, 7, 9, …, 31 days with the aim to assess error distribution between the in-situ observations and CMORPH estimates. We tested forward, central and backward window (FW, CW and BW) schemes to assess the effect of time integration on accumulated rainfall. Accuracy of cumulative rainfall depth is assessed by Root Mean Squared Error (RMSE). To systematically correct all CMORPH estimates, station based bias factors are spatially interpolated to yield a bias factor map. Reliability of interpolation is assessed by cross validation. The uncorrected CMORPH rainfall images are multiplied by the interpolated bias map to result in bias corrected CMORPH estimates. Findings are evaluated by RMSE, correlation coefficient (r) and standard deviation (SD). Results showed existence of bias in the CMORPH rainfall. It is found that the 7 days SW approach performs best for bias correction of CMORPH rainfall. The outcome of this study showed the efficiency of our bias correction approach. PMID:27314363

  11. Evaluation of Bias Correction Method for Satellite-Based Rainfall Data.

    Science.gov (United States)

    Bhatti, Haris Akram; Rientjes, Tom; Haile, Alemseged Tamiru; Habib, Emad; Verhoef, Wouter

    2016-06-15

    With the advances in remote sensing technology, satellite-based rainfall estimates are gaining attraction in the field of hydrology, particularly in rainfall-runoff modeling. Since estimates are affected by errors correction is required. In this study, we tested the high resolution National Oceanic and Atmospheric Administration's (NOAA) Climate Prediction Centre (CPC) morphing technique (CMORPH) satellite rainfall product (CMORPH) in the Gilgel Abbey catchment, Ethiopia. CMORPH data at 8 km-30 min resolution is aggregated to daily to match in-situ observations for the period 2003-2010. Study objectives are to assess bias of the satellite estimates, to identify optimum window size for application of bias correction and to test effectiveness of bias correction. Bias correction factors are calculated for moving window (MW) sizes and for sequential windows (SW's) of 3, 5, 7, 9, …, 31 days with the aim to assess error distribution between the in-situ observations and CMORPH estimates. We tested forward, central and backward window (FW, CW and BW) schemes to assess the effect of time integration on accumulated rainfall. Accuracy of cumulative rainfall depth is assessed by Root Mean Squared Error (RMSE). To systematically correct all CMORPH estimates, station based bias factors are spatially interpolated to yield a bias factor map. Reliability of interpolation is assessed by cross validation. The uncorrected CMORPH rainfall images are multiplied by the interpolated bias map to result in bias corrected CMORPH estimates. Findings are evaluated by RMSE, correlation coefficient (r) and standard deviation (SD). Results showed existence of bias in the CMORPH rainfall. It is found that the 7 days SW approach performs best for bias correction of CMORPH rainfall. The outcome of this study showed the efficiency of our bias correction approach.

  12. Evaluation of Bias Correction Method for Satellite-Based Rainfall Data

    Directory of Open Access Journals (Sweden)

    Haris Akram Bhatti

    2016-06-01

    Full Text Available With the advances in remote sensing technology, satellite-based rainfall estimates are gaining attraction in the field of hydrology, particularly in rainfall-runoff modeling. Since estimates are affected by errors correction is required. In this study, we tested the high resolution National Oceanic and Atmospheric Administration’s (NOAA Climate Prediction Centre (CPC morphing technique (CMORPH satellite rainfall product (CMORPH in the Gilgel Abbey catchment, Ethiopia. CMORPH data at 8 km-30 min resolution is aggregated to daily to match in-situ observations for the period 2003–2010. Study objectives are to assess bias of the satellite estimates, to identify optimum window size for application of bias correction and to test effectiveness of bias correction. Bias correction factors are calculated for moving window (MW sizes and for sequential windows (SW’s of 3, 5, 7, 9, …, 31 days with the aim to assess error distribution between the in-situ observations and CMORPH estimates. We tested forward, central and backward window (FW, CW and BW schemes to assess the effect of time integration on accumulated rainfall. Accuracy of cumulative rainfall depth is assessed by Root Mean Squared Error (RMSE. To systematically correct all CMORPH estimates, station based bias factors are spatially interpolated to yield a bias factor map. Reliability of interpolation is assessed by cross validation. The uncorrected CMORPH rainfall images are multiplied by the interpolated bias map to result in bias corrected CMORPH estimates. Findings are evaluated by RMSE, correlation coefficient (r and standard deviation (SD. Results showed existence of bias in the CMORPH rainfall. It is found that the 7 days SW approach performs best for bias correction of CMORPH rainfall. The outcome of this study showed the efficiency of our bias correction approach.

  13. [Hydroxylamine conversion by anammox enrichment].

    Science.gov (United States)

    Hu, Anhui; Zheng, Ping; Lu, Huifeng; Ding, Shuang; Wang, Caihua

    2010-04-01

    Hydroxylamine is an important intermediate product of anammox. This study was focused on the characteristics of hydroxylamine and nitrite conversions by anammox enrichment. The changes of nitrogenous substrates and related products with time were measured using batch tests with anammox enrichment as inoculum. Since hydroxylamine didn't react with nitrite in uninoculated control culture, these two compounds were chemically stable. Both of them decreased with time in anammox enrichment inoculated cultures, in which ammonia as intermediate product would be produced and converted with the maximum concentration being 0.338 mg/L. The total nitrogen concentration decreased from 4.694 mmol/L to 0.812 mmol/L with conversion rate 82.7% in the end. When hydroxylamine and nitrite concentrations were about 2.5 mmol/L respectively, the maximum specific sludge conversion rates of hydroxylamine was 0.535 mmol/(gVSS.h), which was 1.81 times bigger than that of ammonia in ammonia reaction system; the maximum specific sludge rate of total nitrogen was slightly higher than that in ammonia reaction system. When hydroxylamine concentration increased to 5.0 mmol/L, the hydroxylamine and nitrite conversion rates promoted by 26.7% and 120.7% respectively; and the maximum ammonia accumulated was 1.810 mmol/L. When nitrite concentration increased to 5.0 mmol/L, the hydroxylamine and nitrite conversion rates promoted by 6.9% and 9.0% respectively; and the maximum ammonia accumulated was 0.795 mmol/L. Anammox enrichment was capable of converting hydroxylamine and nitrite simultaneously and had the higher conversion rate of hydroxylamine than ammonia conversion rate. Hydroxylamine and nitrite conversion rates were less affected by increase in nitrite concentration, but more significantly influenced by increase in hydroxylamine. The maximum ammonia concentration accumulated would rise as the result of increasing both hydroxylamine and nitrite. The result of experiment was consistent with pathway

  14. Decision-making heuristics and biases across the life span

    Science.gov (United States)

    Strough, JoNell; Karns, Tara E.; Schlosnagle, Leo

    2013-01-01

    We outline a contextual and motivational model of judgment and decision-making (JDM) biases across the life span. Our model focuses on abilities and skills that correspond to deliberative, experiential, and affective decision-making processes. We review research that addresses links between JDM biases and these processes as represented by individual differences in specific abilities and skills (e.g., fluid and crystallized intelligence, executive functioning, emotion regulation, personality traits). We focus on two JDM biases—the sunk-cost fallacy (SCF) and the framing effect. We trace the developmental trajectory of each bias from preschool through middle childhood, adolescence, early adulthood, and later adulthood. We conclude that life-span developmental trajectories differ depending on the bias investigated. Existing research suggests relative stability in the framing effect across the life span and decreases in the SCF with age, including in later life. We highlight directions for future research on JDM biases across the life span, emphasizing the need for process-oriented research and research that increases our understanding of JDM biases in people’s everyday lives. PMID:22023568

  15. TCABR Tokamak scrape-off layer turbulence with DC biasing

    International Nuclear Information System (INIS)

    Heller, M.V.A.P.; Ferreira, A.A.; Caldas, I.L.; Nascimento, I.C.

    2004-01-01

    Turbulence and particle transport in plasma scrape-off layer have been controlled by external electric fields. This control can be achieved by a biasing electrode located inside the plasma. We investigate plasma turbulence changes in the scrape-off layer of TCABR tokamak introduced by DC biasing an electrode inside the plasma. Our investigation is based on the alterations observed on the wavelet power spectra and on the intermittent burst sequences of plasma potential and density fluctuations measured by a set of Langmuir probes. Biasing the electrode changes the turbulence statistics and the bursts intermittence. With the imposed external electric field, fluctuation amplitudes, phase velocities, and anomalous particle transport are modified. Transport reduction for higher frequencies induced by the biasing could be due to the strong de-phasing between density and potential fluctuations. The mode coupling increases with the perturbation for the high frequency broadband fluctuations. The total (laminar and bursting) radial particle transport is reduced by about 25% by DC biasing. Bursts contribution to total transport is 15% and for the studied conditions this contribution does not change much with the bias perturbation

  16. Apparatus bias and place conditioning with ethanol in mice.

    Science.gov (United States)

    Cunningham, Christopher L; Ferree, Nikole K; Howard, MacKenzie A

    2003-12-01

    Although the distinction between "biased" and "unbiased" is generally recognized as an important methodological issue in place conditioning, previous studies have not adequately addressed the distinction between a biased/unbiased apparatus and a biased/unbiased stimulus assignment procedure. Moreover, a review of the recent literature indicates that many reports (70% of 76 papers published in 2001) fail to provide adequate information about apparatus bias. This issue is important because the mechanisms underlying a drug's effect in the place-conditioning procedure may differ depending on whether the apparatus is biased or unbiased. The present studies were designed to assess the impact of apparatus bias and stimulus assignment procedure on ethanol-induced place conditioning in mice (DBA/2 J). A secondary goal was to compare various dependent variables commonly used to index conditioned place preference. Apparatus bias was manipulated by varying the combination of tactile (floor) cues available during preference tests. Experiment 1 used an unbiased apparatus in which the stimulus alternatives were equally preferred during a pre-test as indicated by the group average. Experiment 2 used a biased apparatus in which one of the stimuli was strongly preferred by most mice (mean % time on cue = 67%) during the pre-test. In both studies, the stimulus paired with drug (CS+) was assigned randomly (i.e., an "unbiased" stimulus assignment procedure). Experimental mice received four pairings of CS+ with ethanol (2 g/kg, i.p.) and four pairings of the alternative stimulus (CS-) with saline; control mice received saline on both types of trial. Each experiment concluded with a 60-min choice test. With the unbiased apparatus (experiment 1), significant place conditioning was obtained regardless of whether drug was paired with the subject's initially preferred or non-preferred stimulus. However, with the biased apparatus (experiment 2), place conditioning was apparent only when

  17. Effects of Cognitive Bias Modification Training via Smartphones

    Directory of Open Access Journals (Sweden)

    Ranming Yang

    2017-08-01

    Full Text Available Background and Objectives: Negative cognitive biases have been linked to anxiety and mood problems. Accumulated data from laboratory studies show that positive and negative interpretation styles with accompanying changes in mood can be induced through cognitive bias modification (CBM paradigms. Despite the therapeutic potential of positive training effects, few studies have explored training paradigms administered via smartphones. The current study aimed to compare the effectiveness of three different types of training programmes (cognitive bias modification-attention, CBM-A; cognitive bias modification-interpretation, CBM-I; attention and interpretation modification, AIM administered via smart-phones by using a control condition (CC.Methods:Seventy-six undergraduate participants with high social anxiety (Liebowitz Social Anxiety Scale, LSAS ≥ 30 were randomly assigned to four groups: CBM-A (n = 20, CBM-I (n = 20, AIM (n = 16, and CC (n = 20.Results: The results showed that the effects of CBM training, CBM-I training, or AIM training vs. CC for attention yielded no significant differences in dot-probe attention bias scores. The CBM-I group showed significantly less threat interpretation and more benign interpretation than the CC group on interpretation bias scores.Conclusions: The present results supported the feasibility of delivering CBM-I via smartphones, but the effectiveness of CBM-A and AIM training via smartphones was limited.

  18. Speed Biases With Real-Life Video Clips

    Directory of Open Access Journals (Sweden)

    Federica Rossi

    2018-03-01

    Full Text Available We live almost literally immersed in an artificial visual world, especially motion pictures. In this exploratory study, we asked whether the best speed for reproducing a video is its original, shooting speed. By using adjustment and double staircase methods, we examined speed biases in viewing real-life video clips in three experiments, and assessed their robustness by manipulating visual and auditory factors. With the tested stimuli (short clips of human motion, mixed human-physical motion, physical motion and ego-motion, speed underestimation was the rule rather than the exception, although it depended largely on clip content, ranging on average from 2% (ego-motion to 32% (physical motion. Manipulating display size or adding arbitrary soundtracks did not modify these speed biases. Estimated speed was not correlated with estimated duration of these same video clips. These results indicate that the sense of speed for real-life video clips can be systematically biased, independently of the impression of elapsed time. Measuring subjective visual tempo may integrate traditional methods that assess time perception: speed biases may be exploited to develop a simple, objective test of reality flow, to be used for example in clinical and developmental contexts. From the perspective of video media, measuring speed biases may help to optimize video reproduction speed and validate “natural” video compression techniques based on sub-threshold temporal squeezing.

  19. Microbial Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, Merry [American Society for Microbiology (ASM), Washington, DC (United States); Wall, Judy D. [Univ. of Missouri, Columbia, MO (United States)

    2006-10-01

    The American Academy of Microbiology convened a colloquium March 10-12, 2006, in San Francisco, California, to discuss the production of energy fuels by microbial conversions. The status of research into various microbial energy technologies, the advantages and disadvantages of each of these approaches, research needs in the field, and education and training issues were examined, with the goal of identifying routes for producing biofuels that would both decrease the need for fossil fuels and reduce greenhouse gas emissions. Currently, the choices for providing energy are limited. Policy makers and the research community must begin to pursue a broader array of potential energy technologies. A diverse energy portfolio that includes an assortment of microbial energy choices will allow communities and consumers to select the best energy solution for their own particular needs. Funding agencies and governments alike need to prepare for future energy needs by investing both in the microbial energy technologies that work today and in the untested technologies that will serve the world’s needs tomorrow. More mature bioprocesses, such as ethanol production from starchy materials and methane from waste digestors, will find applications in the short term. However, innovative techniques for liquid fuel or biohydrogen production are among the longer term possibilities that should also be vigorously explored, starting now. Microorganisms can help meet human energy needs in any of a number of ways. In their most obvious role in energy conversion, microorganisms can generate fuels, including ethanol, hydrogen, methane, lipids, and butanol, which can be burned to produce energy. Alternatively, bacteria can be put to use in microbial fuel cells, where they carry out the direct conversion of biomass into electricity. Microorganisms may also be used some day to make oil and natural gas technologies more efficient by sequestering carbon or by assisting in the recovery of oil and

  20. A Framework for Integrating Implicit Bias Recognition Into Health Professions Education.

    Science.gov (United States)

    Sukhera, Javeed; Watling, Chris

    2018-01-01

    Existing literature on implicit bias is fragmented and comes from a variety of fields like cognitive psychology, business ethics, and higher education, but implicit-bias-informed educational approaches have been underexplored in health professions education and are difficult to evaluate using existing tools. Despite increasing attention to implicit bias recognition and management in health professions education, many programs struggle to meaningfully integrate these topics into curricula. The authors propose a six-point actionable framework for integrating implicit bias recognition and management into health professions education that draws on the work of previous researchers and includes practical tools to guide curriculum developers. The six key features of this framework are creating a safe and nonthreatening learning context, increasing knowledge about the science of implicit bias, emphasizing how implicit bias influences behaviors and patient outcomes, increasing self-awareness of existing implicit biases, improving conscious efforts to overcome implicit bias, and enhancing awareness of how implicit bias influences others. Important considerations for designing implicit-bias-informed curricula-such as individual and contextual variables, as well as formal and informal cultural influences-are discussed. The authors also outline assessment and evaluation approaches that consider outcomes at individual, organizational, community, and societal levels. The proposed framework may facilitate future research and exploration regarding the use of implicit bias in health professions education.

  1. Conduction channels at finite bias in single-atom gold contacts

    DEFF Research Database (Denmark)

    Brandbyge, Mads; Kobayashi, Nobuhiko; Tsukada, Masaru

    1999-01-01

    We consider the effect of a finite voltage bias on the conductance of single-atom gold contacts. We employ a nonorthogonal spn-tight-binding Hamiltonian combined with a local charge neutrality assumption. The conductance and charge distributions for finite bias are calculated using the nonequilib......We consider the effect of a finite voltage bias on the conductance of single-atom gold contacts. We employ a nonorthogonal spn-tight-binding Hamiltonian combined with a local charge neutrality assumption. The conductance and charge distributions for finite bias are calculated using...... of the eigenchannels projected onto tight-binding orbitals. We find a single almost fully transmitting channel with mainly s character for low bias while for high bias this channel becomes less transmitting and additional channels involving only d orbitals start to conduct....

  2. 5 CFR 534.506 - Conversion provisions.

    Science.gov (United States)

    2010-01-01

    ... conversion, other than to the minimum rate under 5 U.S.C. 5376, the increase must be approved by the head of... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Conversion provisions. 534.506 Section... OTHER SYSTEMS Pay for Senior-Level and Scientific and Professional Positions § 534.506 Conversion...

  3. 47 CFR 80.761 - Conversion graphs.

    Science.gov (United States)

    2010-10-01

    ... MARITIME SERVICES Standards for Computing Public Coast Station VHF Coverage § 80.761 Conversion graphs. The following graphs must be employed where conversion from one to the other of the indicated types of units is... 47 Telecommunication 5 2010-10-01 2010-10-01 false Conversion graphs. 80.761 Section 80.761...

  4. Bias Correction with Jackknife, Bootstrap, and Taylor Series

    OpenAIRE

    Jiao, Jiantao; Han, Yanjun; Weissman, Tsachy

    2017-01-01

    We analyze the bias correction methods using jackknife, bootstrap, and Taylor series. We focus on the binomial model, and consider the problem of bias correction for estimating $f(p)$, where $f \\in C[0,1]$ is arbitrary. We characterize the supremum norm of the bias of general jackknife and bootstrap estimators for any continuous functions, and demonstrate the in delete-$d$ jackknife, different values of $d$ may lead to drastically different behavior in jackknife. We show that in the binomial ...

  5. Developmental Changes in the Whole Number Bias

    Science.gov (United States)

    Braithwaite, David W.; Siegler, Robert S.

    2018-01-01

    Many students' knowledge of fractions is adversely affected by whole number bias, the tendency to focus on the separate whole number components (numerator and denominator) of a fraction rather than on the fraction's magnitude (ratio of numerator to denominator). Although whole number bias appears early in the fraction learning process and under…

  6. Converse magnetoelectric effect in laminated composite of Metglas and Pb(Zr,TiO3 with screen-printed interdigitated electrodes

    Directory of Open Access Journals (Sweden)

    Yuan Zhang

    2014-06-01

    Full Text Available In this study, we investigate the converse magnetoelectric (CME effect in a laminated composite consisting of Metglas ribbons and Pb(Zr,TiO3 (PZT plate with screen-printed interdigitated electrodes and operating in longitudinal magnetization and longitudinal polarization (L-L mode. Large CME coefficients of 0.134 G·cm/V at frequency of 1 kHz and 2.75 G·cm/V at resonance frequency of 43.5 kHz under a small bias magnetic field of 7 Oe are achieved. The large CME effect can be attributed to the L-L mode and low mechanical loss of the Metglas/PZT laminated composite.

  7. Biases in cost measurement for economic evaluation studies in health care.

    Science.gov (United States)

    Jacobs, P; Baladi, J F

    1996-01-01

    This paper addresses the issue of biases in cost measures which used in economic evaluation studies. The basic measure of hospital costs which is used by most investigators is unit cost. Focusing on this measure, a set of criteria which the basic measures must fulfil in order to approximate the marginal cost (MC) of a service for the relevant product, in the representative site, was identified. Then four distinct biases--a scale bias, a case mix bias, a methods bias and a site selection bias--each of which reflects the divergence of the unit cost measure from the desired MC measure, were identified. Measures are proposed for several of these biases and it is suggested how they can be corrected.

  8. Is Czech Export still Biased towards the Eastern Markets?

    Directory of Open Access Journals (Sweden)

    Lucie Coufalová

    2017-01-01

    Full Text Available There were special relationships among the COMECON members during the period of the centrally planning system. Czechoslovak trade/export was naturally biased towards these countries. The goal of this paper is to find out if there still exists any export bias towards the Russian or the ex‑COMECON markets. In our research approach we use gravity models. We revealed that taking into consideration growth in GDP, geographical distance and institutions there is no bias towards the Russian or the CIS markets. But we discovered a bias towards the ex‑COMECON contemporary members of the EU.

  9. The Conversion of Wiswesser Line Notations to Ring Codes. I. The Conversion of Ring Systems

    Science.gov (United States)

    Granito, Charles E.; And Others

    1972-01-01

    The computerized conversion of Wiswesser Line Notations to Ring Codes, using a two-part approach, and the set of computer programs generated for the conversion of ring systems are described. (9 references) (Author)

  10. The conversational interface talking to smart devices

    CERN Document Server

    McTear, Michael; Griol, David

    2016-01-01

    This book provides a comprehensive introduction to the conversational interface, which is becoming the main mode of interaction with virtual personal assistants, smart devices, various types of wearables, and social robots. The book consists of four parts: Part I presents the background to conversational interfaces, examining past and present work on spoken language interaction with computers; Part II covers the various technologies that are required to build a conversational interface along with practical chapters and exercises using open source tools; Part III looks at interactions with smart devices, wearables, and robots, and then goes on to discusses the role of emotion and personality in the conversational interface; Part IV examines methods for evaluating conversational interfaces and discusses future directions. · Presents a comprehensive overview of the various technologies that underlie conversational user interfaces; · Combines descriptions of conversational user interface technologies with a gui...

  11. Dose conversion factors

    International Nuclear Information System (INIS)

    Kocher, D.C.; Eckerman, K.F.

    1992-01-01

    The following is discussed in this report: concepts and quantities used in calculating radiation dose from internal and external exposure. Tabulations of dose conversion factor for internal and external exposure to radionuclides. Dose conversion factors give dose per unit intake (internal) or dose per unit concentration in environment (external). Intakes of radionuclides for internal exposure and concentrations of radionuclides in environment for external exposure are assumed to be known. Intakes and concentrations are obtained, e.g., from analyses of environmental transport and exposure pathways. differences between dosimetry methods for radionuclides and hazardous chemicals are highlighted

  12. Magnetohydrodynamic energy conversion

    International Nuclear Information System (INIS)

    Rosa, R.J.

    1987-01-01

    The object of this book is to present a review of the basic principles and practical aspects of magnetohydrodynamic (MHD) energy conversion. The author has tried to give qualitative semiphysical arguments where possible for the benefit of the reader who is unfamiliar with plasma physics. The aim of MHD energy conversion is to apply to a specific practical goal a part of what has become a vast area of science called plasma physics. The author has attempted to note in the text where a broader view might be fruitful and to give appropriate references

  13. Lost in translation: Review of identification bias, translation bias and research waste in dentistry.

    Science.gov (United States)

    Layton, Danielle M; Clarke, Michael

    2016-01-01

    To review how articles are retrieved from bibliographic databases, what article identification and translation problems have affected research, and how these problems can contribute to research waste and affect clinical practice. This literature review sought and appraised articles regarding identification- and translation-bias in the medical and dental literature, which limit the ability of users to find research articles and to use these in practice. Articles can be retrieved from bibliographic databases by performing a word or index-term (for example, MeSH for MEDLINE) search. Identification of articles is challenging when it is not clear which words are most relevant, and which terms have been allocated to indexing fields. Poor reporting quality of abstracts and articles has been reported across the medical literature at large. Specifically in dentistry, research regarding time-to-event survival analyses found the allocation of MeSH terms to be inconsistent and inaccurate, important words were omitted from abstracts by authors, and the quality of reporting in the body of articles was generally poor. These shortcomings mean that articles will be difficult to identify, and difficult to understand if found. Use of specialized electronic search strategies can decrease identification bias, and use of tailored reporting guidelines can decrease translation bias. Research that cannot be found, or cannot be used results in research waste, and undermines clinical practice. Identification- and translation-bias have been shown to affect time-to-event dental articles, are likely affect other fields of research, and are largely unrecognized by authors and evidence seekers alike. By understanding that the problems exist, solutions can be sought to improve identification and translation of our research. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  14. Blind-date Conversation Joining

    Directory of Open Access Journals (Sweden)

    Luca Cesari

    2013-07-01

    Full Text Available We focus on a form of joining conversations among multiple parties in service-oriented applications where a client may asynchronously join an existing conversation without need to know in advance any information about it. More specifically, we show how the correlation mechanism provided by orchestration languages enables a form of conversation joining that is completely transparent to clients and that we call 'blind-date joining'. We provide an implementation of this strategy by using the standard orchestration language WS-BPEL. We then present its formal semantics by resorting to COWS, a process calculus specifically designed for modelling service-oriented applications. We illustrate our approach by means of a simple, but realistic, case study from the online games domain.

  15. Biomass thermochemical conversion program: 1987 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.; Stevens, D.J.; Gerber, M.A.

    1988-01-01

    The objective of the Biomass Thermochemical Conversion Program is to generate a base of scientific data and conversion process information that will lead to establishment of cost-effective processes for conversion of biomass resources into clean fuels. To accomplish this objective, in fiscal year 1987 the Thermochemical Conversion Program sponsored research activities in the following four areas: Liquid Hydrocarbon Fuels Technology; Gasification Technology; Direct Combustion Technology; Program Support Activities. In this report an overview of the Thermochemical Conversion Program is presented. Specific research projects are then described. Major accomplishments for 1987 are summarized.

  16. Biomass thermochemical conversion program. 1985 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.; Stevens, D.J.; Gerber, M.A.

    1986-01-01

    Wood and crop residues constitute a vast majority of the biomass feedstocks available for conversion, and thermochemical processes are well suited for conversion of these materials. The US Department of Energy (DOE) is sponsoring research on this conversion technology for renewable energy through its Biomass Thermochemical Conversion Program. The Program is part of DOE's Biofuels and Municipal Waste Technology Division, Office of Renewable Technologies. This report briefly describes the Thermochemical Conversion Program structure and summarizes the activities and major accomplishments during fiscal year 1985. 32 figs., 4 tabs.

  17. The Battle over Studies of Faculty Bias

    Science.gov (United States)

    Gravois, John

    2007-01-01

    The American Federation of Teachers (AFT) recently commissioned a study to review the research that finds liberal bias run amok in academe. Believing that the AFT is not a dispassionate observer of this debate, this article provides "The Chronicle of Higher Education's" survey of the genre. The studies reviewed include: (1) "Political Bias in the…

  18. Conversational sensemaking

    Science.gov (United States)

    Preece, Alun; Webberley, Will; Braines, Dave

    2015-05-01

    Recent advances in natural language question-answering systems and context-aware mobile apps create opportunities for improved sensemaking in a tactical setting. Users equipped with mobile devices act as both sensors (able to acquire information) and effectors (able to act in situ), operating alone or in collectives. The currently- dominant technical approaches follow either a pull model (e.g. Apple's Siri or IBM's Watson which respond to users' natural language queries) or a push model (e.g. Google's Now which sends notifications to a user based on their context). There is growing recognition that users need more flexible styles of conversational interaction, where they are able to freely ask or tell, be asked or told, seek explanations and clarifications. Ideally such conversations should involve a mix of human and machine agents, able to collaborate in collective sensemaking activities with as few barriers as possible. Desirable capabilities include adding new knowledge, collaboratively building models, invoking specific services, and drawing inferences. As a step towards this goal, we collect evidence from a number of recent pilot studies including natural experiments (e.g. situation awareness in the context of organised protests) and synthetic experiments (e.g. human and machine agents collaborating in information seeking and spot reporting). We identify some principles and areas of future research for "conversational sensemaking".

  19. Exchange bias mediated by interfacial nanoparticles (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Berkowitz, A. E., E-mail: aberk@ucsd.edu [Department of Physics, University of California, San Diego, La Jolla, California 92093 (United States); Center for Magnetic Recording Research, University of California, California 92093 (United States); Sinha, S. K. [Department of Physics, University of California, San Diego, La Jolla, California 92093 (United States); Fullerton, E. E. [Center for Magnetic Recording Research, University of California, California 92093 (United States); Smith, D. J. [Department of Physics, Arizona State University, Tempe, Arizona 85287 (United States)

    2015-05-07

    The objective of this study on the iconic exchange-bias bilayer Permalloy/CoO has been to identify those elements of the interfacial microstructure and accompanying magnetic properties that are responsible for the exchange-bias and hysteretic properties of this bilayer. Both epitaxial and polycrystalline samples were examined. X-ray and neutron reflectometry established that there existed an interfacial region, of width ∼1 nm, whose magnetic properties differed from those of Py or CoO. A model was developed for the interfacial microstructure that predicts all the relevant properties of this system; namely; the temperature and Permalloy thickness dependence of the exchange-bias, H{sub EX}, and coercivity, H{sub C}; the much smaller measured values of H{sub EX} from what was nominally expected; the different behavior of H{sub EX} and H{sub C} in epitaxial and polycrystalline bilayers. A surprising result is that the exchange-bias does not involve direct exchange-coupling between Permalloy and CoO, but rather is mediated by CoFe{sub 2}O{sub 4} nanoparticles in the interfacial region.

  20. Mechanisms of Ectopic Gene Conversion

    Directory of Open Access Journals (Sweden)

    P.J. Hastings

    2010-11-01

    Full Text Available Gene conversion (conversion, the unidirectional transfer of DNA sequence information, occurs as a byproduct of recombinational repair of broken or damaged DNA molecules. Whereas excision repair processes replace damaged DNA by copying the complementary sequence from the undamaged strand of duplex DNA, recombinational mechanisms copy similar sequence, usually in another molecule, to replace the damaged sequence. In mitotic cells the other molecule is usually a sister chromatid, and the repair does not lead to genetic change. Less often a homologous chromosome or homologous sequence in an ectopic position is used. Conversion results from repair in two ways. First, if there was a double-strand gap at the site of a break, homologous sequence will be used as the template for synthesis to fill the gap, thus transferring sequence information in both strands. Second, recombinational repair uses complementary base pairing, and the heteroduplex molecule so formed is a source of conversion, both as heteroduplex and when donor (undamaged template information is retained after correction of mismatched bases in heteroduplex. There are mechanisms that favour the use of sister molecules that must fail before ectopic homology can be used. Meiotic recombination events lead to the formation of crossovers required in meiosis for orderly segregation of pairs of homologous chromosomes. These events result from recombinational repair of programmed double-strand breaks, but in contrast with mitotic recombination, meiotic recombinational events occur predominantly between homologous chromosomes, so that transfer of sequence differences by conversion is very frequent. Transient recombination events that do not form crossovers form both between homologous chromosomes and between regions of ectopic homology, and leave their mark in the occurrence of frequent non-crossover conversion, including ectopic conversion.

  1. The Biases of Thinking Fast and Thinking Slow

    OpenAIRE

    Streeb, Dirk; Chen, Min; Keim, Daniel A.

    2017-01-01

    Visualization is a human-centric process, which is inevitably as- sociated with potential biases in humans’ judgment and decision making. While the discussions on humans’ biases have been heavily influenced the work of Daniel Kahneman as summarized in his book “Thinking, Fast and Slow” [8], there have also been viewpoints in psychology in favor of heuristics (e.g., [6]). In this paper, we present a balanced discourse on the humans’ heuristics and biases as the two sides of the same coin. In p...

  2. Conversion factors and oil statistics

    International Nuclear Information System (INIS)

    Karbuz, Sohbet

    2004-01-01

    World oil statistics, in scope and accuracy, are often far from perfect. They can easily lead to misguided conclusions regarding the state of market fundamentals. Without proper attention directed at statistic caveats, the ensuing interpretation of oil market data opens the door to unnecessary volatility, and can distort perception of market fundamentals. Among the numerous caveats associated with the compilation of oil statistics, conversion factors, used to produce aggregated data, play a significant role. Interestingly enough, little attention is paid to conversion factors, i.e. to the relation between different units of measurement for oil. Additionally, the underlying information regarding the choice of a specific factor when trying to produce measurements of aggregated data remains scant. The aim of this paper is to shed some light on the impact of conversion factors for two commonly encountered issues, mass to volume equivalencies (barrels to tonnes) and for broad energy measures encountered in world oil statistics. This paper will seek to demonstrate how inappropriate and misused conversion factors can yield wildly varying results and ultimately distort oil statistics. Examples will show that while discrepancies in commonly used conversion factors may seem trivial, their impact on the assessment of a world oil balance is far from negligible. A unified and harmonised convention for conversion factors is necessary to achieve accurate comparisons and aggregate oil statistics for the benefit of both end-users and policy makers

  3. Single-Receiver GPS Phase Bias Resolution

    Science.gov (United States)

    Bertiger, William I.; Haines, Bruce J.; Weiss, Jan P.; Harvey, Nathaniel E.

    2010-01-01

    Existing software has been modified to yield the benefits of integer fixed double-differenced GPS-phased ambiguities when processing data from a single GPS receiver with no access to any other GPS receiver data. When the double-differenced combination of phase biases can be fixed reliably, a significant improvement in solution accuracy is obtained. This innovation uses a large global set of GPS receivers (40 to 80 receivers) to solve for the GPS satellite orbits and clocks (along with any other parameters). In this process, integer ambiguities are fixed and information on the ambiguity constraints is saved. For each GPS transmitter/receiver pair, the process saves the arc start and stop times, the wide-lane average value for the arc, the standard deviation of the wide lane, and the dual-frequency phase bias after bias fixing for the arc. The second step of the process uses the orbit and clock information, the bias information from the global solution, and only data from the single receiver to resolve double-differenced phase combinations. It is called "resolved" instead of "fixed" because constraints are introduced into the problem with a finite data weight to better account for possible errors. A receiver in orbit has much shorter continuous passes of data than a receiver fixed to the Earth. The method has parameters to account for this. In particular, differences in drifting wide-lane values must be handled differently. The first step of the process is automated, using two JPL software sets, Longarc and Gipsy-Oasis. The resulting orbit/clock and bias information files are posted on anonymous ftp for use by any licensed Gipsy-Oasis user. The second step is implemented in the Gipsy-Oasis executable, gd2p.pl, which automates the entire process, including fetching the information from anonymous ftp

  4. Matrilateral Bias in Human Grandmothering

    Directory of Open Access Journals (Sweden)

    Martin Daly

    2017-09-01

    Full Text Available Children receive more care and resources from their maternal grandmothers than from their paternal grandmothers. This asymmetry is the “matrilateral bias” in grandmaternal investment. Here, we synopsize the evolutionary theories that predict such a bias, and review evidence of its cross-cultural generality and magnitude. Evolutionists have long maintained that investing in a daughter’s child yields greater fitness returns, on average, than investing in a son’s child because of paternity uncertainty: the son’s putative progeny may have been sired by someone else. Recent theoretical work has identified an additional natural selective basis for the matrilateral bias that may be no less important: supporting grandchildren lightens the load on their mother, increasing her capacity to pursue her fitness in other ways, and if she invests those gains either in her natal relatives or in children of a former or future partner, fitness returns accrue to the maternal, but not the paternal, grandmother. In modern democracies, where kinship is reckoned bilaterally and no postmarital residence norms restrict grandmaternal access to grandchildren, many studies have found large matrilateral biases in contact, childcare, and emotional closeness. In other societies, patrilineal ideology and postmarital residence with the husband’s kin (virilocality might be expected to have produced a patrilateral bias instead, but the available evidence refutes this hypothesis. In hunter-gatherers, regardless of professed norms concerning kinship and residence, mothers get needed help at and after childbirth from their mothers, not their mothers-in-law. In traditional agricultural and pastoral societies, patrilineal and virilocal norms are common, but young mothers still turn to their natal families for crucial help, and several studies have documented benefits, including reduced child mortality, associated with access to maternal, but not paternal, grandmothers. Even

  5. Conversational AI: The Science Behind the Alexa Prize

    OpenAIRE

    Ram, Ashwin; Prasad, Rohit; Khatri, Chandra; Venkatesh, Anu; Gabriel, Raefer; Liu, Qing; Nunn, Jeff; Hedayatnia, Behnam; Cheng, Ming; Nagar, Ashish; King, Eric; Bland, Kate; Wartick, Amanda; Pan, Yi; Song, Han

    2018-01-01

    Conversational agents are exploding in popularity. However, much work remains in the area of social conversation as well as free-form conversation over a broad range of domains and topics. To advance the state of the art in conversational AI, Amazon launched the Alexa Prize, a 2.5-million-dollar university competition where sixteen selected university teams were challenged to build conversational agents, known as socialbots, to converse coherently and engagingly with humans on popular topics ...

  6. Energy conversion at dipolarization fronts

    Science.gov (United States)

    Khotyaintsev, Yu. V.; Divin, A.; Vaivads, A.; André, M.; Markidis, S.

    2017-02-01

    We use multispacecraft observations by Cluster in the Earth's magnetotail and 3-D particle-in-cell simulations to investigate conversion of electromagnetic energy at the front of a fast plasma jet. We find that the major energy conversion is happening in the Earth (laboratory) frame, where the electromagnetic energy is being transferred from the electromagnetic field to particles. This process operates in a region with size of the order several ion inertial lengths across the jet front, and the primary contribution to E·j is coming from the motional electric field and the ion current. In the frame of the front we find fluctuating energy conversion with localized loads and generators at sub-ion scales which are primarily related to the lower hybrid drift instability excited at the front; however, these provide relatively small net energy conversion.

  7. Passenger and Cell Phone Conversations in Simulated Driving

    Science.gov (United States)

    Drews, Frank A.; Pasupathi, Monisha; Strayer, David L.

    2008-01-01

    This study examines how conversing with passengers in a vehicle differs from conversing on a cell phone while driving. We compared how well drivers were able to deal with the demands of driving when conversing on a cell phone, conversing with a passenger, and when driving without any distraction. In the conversation conditions, participants were…

  8. The Nanticoke conversion study

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-04-01

    A study was conducted to assess the conversion of the Nanticoke coal-fired power plant to cleaner burning natural gas combined-cycle gas turbines. The Nanticoke Generating Station on Lake Erie is responsible for more than 50 per cent of Ontario Power Generation's (OPG) coal-fired electricity production. The OPG is proposing to work towards compliance with the newly signed Ozone Annex to the 1991 Canada-United States Air Quality Agreement which will require fossil-fueled power plants in southern Ontario to reduce their smog-causing nitrogen oxides emissions by about 50 per cent by 2007. This study assessed the emission reduction benefits and financial costs of conversion compared to continuing to operate Nanticoke as a coal-fired plant. The analysis includes a base case set of data on fuel prices, retrofit costs, fuel efficiencies, annual capacity factors and other parameters. It was determined that conversion would cost the average household less than $3 per month on their electricity bill. Conversion would also reduce emissions nitrogen oxide, a major smog pollutant, by 83 per cent and the particulates that form the most health-threatening portion of smog would be reduced by 100 per cent. 15 tabs., 1 fig.

  9. Distinctive Characteristics of Sexual Orientation Bias Crimes

    Science.gov (United States)

    Stacey, Michele

    2011-01-01

    Despite increased attention in the area of hate crime research in the past 20 years, sexual orientation bias crimes have rarely been singled out for study. When these types of crimes are looked at, the studies are typically descriptive in nature. This article seeks to increase our knowledge of sexual orientation bias by answering the question:…

  10. Minimum bias measurement at 13 TeV

    CERN Document Server

    Orlando, Nicola; The ATLAS collaboration

    2017-01-01

    The modelling of Minimum Bias (MB) is a crucial ingredient to learn about the description of soft QCD processes and to simulate the environment at the LHC with many concurrent pp interactions (pile-up). We summarise the ATLAS minimum bias measurements with proton-proton collision at 13 TeV center-of-mass-energy at the Large Hadron Collider.

  11. The nature of assembly bias - III. Observational properties

    Science.gov (United States)

    Lacerna, Ivan; Padilla, Nelson; Stasyszyn, Federico

    2014-10-01

    We analyse galaxies in groups in the Sloan Digital Sky Survey (SDSS) and find a weak but significant assembly-type bias, where old central galaxies have a higher clustering amplitude (61 ± 9 per cent) at scales >1 h-1 Mpc than young central galaxies of equal host halo mass (Mh ˜ 1011.8 h- 1 M⊙). The observational sample is volume limited out to z = 0.1 with Mr - 5 log (h) ≤ -19.6. We construct a mock catalogue of galaxies that shows a similar signal of assembly bias (46 ± 9 per cent) at the same halo mass. We then adapt the model presented by Lacerna & Padilla (Paper I) to redefine the overdensity peak height, which traces the assembly bias such that galaxies in equal density peaks show the same clustering regardless of their stellar age, but this time using observational features such as a flux limit. The proxy for peak height, which is proposed as a better alternative than the virial mass, consists in the total mass given by the mass of neighbour host haloes in cylinders centred at each central galaxy. The radius of the cylinder is parameterized as a function of stellar age and virial mass. The best-fitting sets of parameters that make the assembly bias signal lower than 5-15 per cent for both SDSS and mock central galaxies are similar. The idea behind the parameterization is not to minimize the bias, but it is to use this method to understand the physical features that produce the assembly bias effect. Even though the tracers of the density field used here differ significantly from those used in Paper I, our analysis of the simulated catalogue indicates that the different tracers produce correlated proxies, and therefore the reason behind assembly bias is the crowding of peaks in both simulations and the SDSS.

  12. Toward a clarification of the taxonomy of "bias" in epidemiology textbooks.

    Science.gov (United States)

    Schwartz, Sharon; Campbell, Ulka B; Gatto, Nicolle M; Gordon, Kirsha

    2015-03-01

    Epidemiology textbooks typically divide biases into 3 general categories-confounding, selection bias, and information bias. Despite the ubiquity of this categorization, authors often use these terms to mean different things. This hinders communication among epidemiologists and confuses students who are just learning about the field. To understand the sources of this problem, we reviewed current general epidemiology textbooks to examine how the authors defined and categorized biases. We found that much of the confusion arises from different definitions of "validity" and from a mixing of 3 overlapping organizational features in defining and differentiating among confounding, selection bias, and information bias: consequence, the result of the problem; cause, the processes that give rise to the problem; and cure, how these biases can be addressed once they occur. By contrast, a consistent taxonomy would provide (1) a clear and consistent definition of what unites confounding, selection bias, and information bias and (2) a clear articulation and consistent application of the feature that distinguishes these categories. Based on a distillation of these textbook discussions, we provide an example of a taxonomy that we think meets these criteria.

  13. Immune markers of social cognitive bias in schizophrenia.

    Science.gov (United States)

    Dunne, Patrick W; Roberts, David L; Quinones, Marlon P; Velligan, Dawn I; Paredes, Madelaine; Walss-Bass, Consuelo

    2017-05-01

    Social cognition is impaired in schizophrenia, is relatively independent of purely neurocognitive domains such as attention and executive functioning, and may be the strongest predictor of functional outcome in this disease. Within a motivated reasoning framework, we tested the hypothesis that the anti-inflammatory Th2-associated cytokines, IL-10 and MDC, would be correlated with behavioral measures of social cognitive threat-detection bias (self-referential gaze detection bias and theory of mind (ToM) bias) in delusional versus non-delusional patients. We administered to schizophrenia patients with delusions (n=21), non-delusional patients (n=39) and controls (n=20) a social cognitive task designed to be sensitive to psychosocial stress response (the Waiting Room Task) and collected plasma levels of inflammatory markers using a bead-based flow immunoassay. Results partially supported our hypothesis. The anti-inflammatory cytokine IL-10 was associated with self-referential ToM bias in the delusional cohort as predicted, and not with non-delusional patients or healthy controls. This bias reflects a documented tendency of schizophrenia patients with delusions to excessively attribute hostile intentions to people in their environment. Since this cytokine correlated only with ToM bias and only in delusional patients, elevated levels of this cytokine in the blood may eventually serve as a useful biomarker distinguishing delusional patients from both non-delusional patients and healthy controls. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  14. Neurologists' understanding and management of conversion disorder.

    Science.gov (United States)

    Kanaan, Richard A; Armstrong, David; Wessely, Simon Charles

    2011-09-01

    Conversion disorder is largely managed by neurologists, for whom it presents great challenges to understanding and management. This study aimed to quantify these challenges, examining how neurologists understand conversion disorder, and what they tell their patients. A postal survey of all consultant neurologists in the UK registered with the Association of British Neurologists. 349 of 591 practising consultant neurologists completed the survey. They saw conversion disorder commonly. While they endorsed psychological models for conversion, they diagnosed it according to features of the clinical presentation, most importantly inconsistency and abnormal illness behaviour. Most of the respondents saw feigning as entangled with conversion disorder, with a minority seeing one as a variant of the other. They were quite willing to discuss psychological factors as long as the patient was receptive but were generally unwilling to discuss feigning even though they saw it as their responsibility. Those who favoured models in terms of feigning were older, while younger, female neurologists preferred psychological models, believed conversion would one day be understood neurologically and found communicating with their conversion patients easier than it had been in the past. Neurologists accept psychological models for conversion disorder but do not employ them in their diagnosis; they do not see conversion as clearly different from feigning. This may be changing as younger, female neurologists endorse psychological views more clearly and find it easier to discuss with their patients.

  15. Referral bias in ALS epidemiological studies.

    Science.gov (United States)

    Logroscino, Giancarlo; Marin, Benoit; Piccininni, Marco; Arcuti, Simona; Chiò, Adriano; Hardiman, Orla; Rooney, James; Zoccolella, Stefano; Couratier, Philippe; Preux, Pierre-Marie; Beghi, Ettore

    2018-01-01

    Despite concerns about the representativeness of patients from ALS tertiary centers as compared to the ALS general population, the extent of referral bias in clinical studies remains largely unknown. Using data from EURALS consortium we aimed to assess nature, extent and impact of referral bias. Four European ALS population-based registries located in Ireland, Piedmont, Puglia, Italy, and Limousin, France, covering 50 million person-years, participated. Demographic and clinic characteristics of ALS patients diagnosed in tertiary referral centers were contrasted with the whole ALS populations enrolled in registries in the same geographical areas. Patients referred to ALS centers were younger (with difference ranging from 1.1 years to 2.4 years), less likely to present a bulbar onset, with a higher proportion of familial antecedents and a longer survival (ranging from 11% to 15%) when compared to the entire ALS population in the same geographic area. A trend for referral bias is present in cohorts drawn from ALS referral centers. The magnitude of the possible referral bias in a particular tertiary center can be estimated through a comparison with ALS patients drawn from registry in the same geographic area. Studies based on clinical cohorts should be cautiously interpreted. The presence of a registry in the same area may improve the complete ascertainment in the referral center.

  16. Tunable reverse-biased graphene/silicon heterojunction Schottky diode sensor.

    Science.gov (United States)

    Singh, Amol; Uddin, Ahsan; Sudarshan, Tangali; Koley, Goutam

    2014-04-24

    A new chemical sensor based on reverse-biased graphene/Si heterojunction diode has been developed that exhibits extremely high bias-dependent molecular detection sensitivity and low operating power. The device takes advantage of graphene's atomically thin nature, which enables molecular adsorption on its surface to directly alter graphene/Si interface barrier height, thus affecting the junction current exponentially when operated in reverse bias and resulting in ultrahigh sensitivity. By operating the device in reverse bias, the work function of graphene, and hence the barrier height at the graphene/Si heterointerface, can be controlled by the bias magnitude, leading to a wide tunability of the molecular detection sensitivity. Such sensitivity control is also possible by carefully selecting the graphene/Si heterojunction Schottky barrier height. Compared to a conventional graphene amperometric sensor fabricated on the same chip, the proposed sensor demonstrated 13 times higher sensitivity for NO₂ and 3 times higher for NH₃ in ambient conditions, while consuming ∼500 times less power for same magnitude of applied voltage bias. The sensing mechanism based on heterojunction Schottky barrier height change has been confirmed using capacitance-voltage measurements. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Naming game with biased assimilation over adaptive networks

    Science.gov (United States)

    Fu, Guiyuan; Zhang, Weidong

    2018-01-01

    The dynamics of two-word naming game incorporating the influence of biased assimilation over adaptive network is investigated in this paper. Firstly an extended naming game with biased assimilation (NGBA) is proposed. The hearer in NGBA accepts the received information in a biased manner, where he may refuse to accept the conveyed word from the speaker with a predefined probability, if the conveyed word is different from his current memory. Secondly, the adaptive network is formulated by rewiring the links. Theoretical analysis is developed to show that the population in NGBA will eventually reach global consensus on either A or B. Numerical simulation results show that the larger strength of biased assimilation on both words, the slower convergence speed, while larger strength of biased assimilation on only one word can slightly accelerate the convergence; larger population size can make the rate of convergence slower to a large extent when it increases from a relatively small size, while such effect becomes minor when the population size is large; the behavior of adaptively reconnecting the existing links can greatly accelerate the rate of convergence especially on the sparse connected network.

  18. Hispanic nurses' experiences of bias in the workplace.

    Science.gov (United States)

    Moceri, Joane T

    2014-01-01

    The continuing issue of health inequity for Hispanics highlights the importance of retaining Hispanic nurses in the workplace. This article describes the use of short answers such as "Describe the bias you experienced" and "If a patient refused care, what was the reason given?" to increase understandings about bias through the descriptions of Hispanic nurses. In this study, bias was defined as those implicit negative stereotypes and attitudes that negatively affect judgments about, evaluations of, and actions toward others. For this qualitative component of a descriptive study employing both qualitative and quantitative methods, 111 Hispanic nurses responded to open-ended questions about experiences of bias that were included with a survey tool and demographic questionnaire. Three themes emerged: being overlooked and undervalued, having to prove competency, and living with "only-ness." Respect was an overarching concept. The written descriptions of bias provided depth and understanding to the quantitative findings. Nurse leaders are well positioned to develop and implement strategies to more effectively support Hispanic nurses and to promote nonbiased interactions in the workplace. Retaining Hispanic nurses is a vital component to address issues of health inequity for Hispanic patients.

  19. Global-local visual biases correspond with visual-spatial orientation.

    Science.gov (United States)

    Basso, Michael R; Lowery, Natasha

    2004-02-01

    Within the past decade, numerous investigations have demonstrated reliable associations of global-local visual processing biases with right and left hemisphere function, respectively (cf. Van Kleeck, 1989). Yet the relevance of these biases to other cognitive functions is not well understood. Towards this end, the present research examined the relationship between global-local visual biases and perception of visual-spatial orientation. Twenty-six women and 23 men completed a global-local judgment task (Kimchi and Palmer, 1982) and the Judgment of Line Orientation Test (JLO; Benton, Sivan, Hamsher, Varney, and Spreen, 1994), a measure of visual-spatial orientation. As expected, men had better performance on JLO. Extending previous findings, global biases were related to better visual-spatial acuity on JLO. The findings suggest that global-local biases and visual-spatial orientation may share underlying cerebral mechanisms. Implications of these findings for other visually mediated cognitive outcomes are discussed.

  20. Large-video-display-format conversion

    NARCIS (Netherlands)

    Haan, de G.

    2000-01-01

    High-quality video-format converters apply motion estimation and motion compensation to prevent jitter resulting from picture-rate conversion, and aliasing due to de-interlacing, in sequences with motion. Although initially considered as too expensive, high-quality conversion is now economically

  1. Teaching autistic children conversational speech using video modeling.

    Science.gov (United States)

    Charlop, M H; Milstein, J P

    1989-01-01

    We assessed the effects of video modeling on acquisition and generalization of conversational skills among autistic children. Three autistic boys observed videotaped conversations consisting of two people discussing specific toys. When criterion for learning was met, generalization of conversational skills was assessed with untrained topics of conversation; new stimuli (toys); unfamiliar persons, siblings, and autistic peers; and other settings. The results indicated that the children learned through video modeling, generalized their conversational skills, and maintained conversational speech over a 15-month period. Video modeling shows much promise as a rapid and effective procedure for teaching complex verbal skills such as conversational speech. PMID:2793634

  2. A fast and zero-biased photodetector based on GaTe-InSe vertical 2D p-n heterojunction

    Science.gov (United States)

    Feng, W.; Jin, Z.; Yuan, J.; Zhang, J.; Jia, S.; Dong, L.; Yoon, J.; Zhou, L.; Vajtai, R.; Tour, J. M.; Ajayan, P. M.; Hu, P.; Lou, J.

    2018-04-01

    p-n junctions serve as the building blocks for fundamental semiconductor devices, such as solar cells, light-emitting diodes (LEDs) and photodetectors. With recent studies unveiling the excellent optoelectronic properties of two-dimensional (2D) semiconductors, they are considered to be superb candidates for high performance p-n junctions. Here, we fabricate a vertical GaTe-InSe van der Waals (vdWs) p-n heterojunction by a PDMS-assisted transfer technique without etching. The fabricated p-n heterojunction shows gate-tunable current-rectifying behavior with a rectification factor reaching 1000. In addition, it features fast photodetection under zero bias as well as a high power conversion efficiency (PCE). Under 405 nm laser excitation, the zero-biased photodetector shows a high responsivity of 13.8 mA W-1 as well as a high external quantum efficiency (EQE) of 4.2%. Long-term stability is also observed and a response time of 20 µs is achieved due to stable and fast carrier transit through the built-in electric field in the depletion region. Fast and efficient charge separation in the vertical 2D p-n junction paves the way for developing 2D photodetectors with zero dark current, high speed and low power consumption.

  3. Reflexive intergroup bias in third-party punishment.

    Science.gov (United States)

    Yudkin, Daniel A; Rothmund, Tobias; Twardawski, Mathias; Thalla, Natasha; Van Bavel, Jay J

    2016-11-01

    Humans show a rare tendency to punish norm-violators who have not harmed them directly-a behavior known as third-party punishment. Research has found that third-party punishment is subject to intergroup bias, whereby people punish members of the out-group more severely than the in-group. Although the prevalence of this behavior is well-documented, the psychological processes underlying it remain largely unexplored. Some work suggests that it stems from people's inherent predisposition to form alliances with in-group members and aggress against out-group members. This implies that people will show reflexive intergroup bias in third-party punishment, favoring in-group over out-group members especially when their capacity for deliberation is impaired. Here we test this hypothesis directly, examining whether intergroup bias in third-party punishment emerges from reflexive, as opposed to deliberative, components of moral cognition. In 3 experiments, utilizing a simulated economic game, we varied participants' group relationship to a transgressor, measured or manipulated the extent to which they relied on reflexive or deliberative judgment, and observed people's punishment decisions. Across group-membership manipulations (American football teams, nationalities, and baseball teams) and 2 assessments of reflexive judgment (response time and cognitive load), reflexive judgment heightened intergroup bias, suggesting that such bias in punishment is inherent to human moral cognition. We discuss the implications of these studies for theories of punishment, cooperation, social behavior, and legal practice. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  4. Understanding antigay bias from a cognitive-affective-behavioral perspective.

    Science.gov (United States)

    Callender, Kevin A

    2015-01-01

    In general, United States citizens have become increasingly more accepting of lesbians and gay men over the past few decades. Despite this shift in public attitudes, antigay bias remains openly tolerated, accepted, practiced, and even defended by a substantial portion of the population. This article reviews why and how antigay bias persists using a cognitive-affective-behavioral perspective that touches on sociocognitive factors such as prejudice and stereotyping, as well as features unique to antigay bias, such as its concealable nature. The article concludes with a discussion of how understanding modern antigay bias through a cognitive-affective-behavioral lens can be applied to reduce discrimination against gays and lesbians.

  5. Seed sexing revealed female bias in two Rumex species

    Directory of Open Access Journals (Sweden)

    Dagmara Kwolek

    2011-07-01

    Full Text Available Sex-ratio bias in seeds of dioecious Rumex species with sex chromosomes is an interesting and still unsettled issue. To resolve gender among seeds of R. acetosa and R. thyrsiflorus (two species with an XX/XY1Y2 sex chromosome system, this work applied a PCR-based method involving DNA markers located on Y chromosomes. Both species showed female-biased primary sex ratios, with female bias greater in R. acetosa than in R. thyrsiflorus. The observed predominance of female seeds is consistent with the view that the female biased sex ratios in Rumex are conditioned not only postzygotically but also prezygotically.

  6. Bias in Examination Test Banks that Accompany Cost Accounting Texts.

    Science.gov (United States)

    Clute, Ronald C.; McGrail, George R.

    1989-01-01

    Eight text banks that accompany cost accounting textbooks were evaluated for the presence of bias in the distribution of correct responses. All but one were found to have considerable bias, and three of eight were found to have significant choice bias. (SK)

  7. The role of cognitive biases in short-term psychodynamic psychotherapy.

    Science.gov (United States)

    Kramer, Ueli; Ortega, Diana; Ambresin, Gilles; Despland, Jean-Nicolas; de Roten, Yves

    2018-06-01

    The concept of biased thinking - or cognitive biases - is relevant to psychotherapy research and clinical conceptualization, beyond cognitive theories. The present naturalistic study aimed to examine the changes in biased thinking over the course of a short-term dynamic psychotherapy (STDP) and to discover potential links between these changes and symptomatic improvement. This study focuses on 32 self-referred patients consulting for Adjustment Disorder according to DSM-IV-TR. The therapists were experienced psychodynamically oriented psychiatrists and psychotherapists. Coding of cognitive biases (using the Cognitive Errors Rating Scale; CERS) was made by external raters based on transcripts of interviews of psychotherapy; the reliability of these ratings on a randomly chosen 24% of all sessions was established. Based on the Symptom Check List SCL-90-R given before and after, the Reliable Change Index (RCI) was used. The assessment of cognitive errors was done at three time points: early (session 4-7), mid-treatment (session 12-17), and close to the end (after session 20) of the treatment. The results showed that the total frequency of cognitive biases was stable over time (p = .20), which was true both for positive and for negative cognitive biases. In exploring the three main subscales of the CERS, we found a decrease in selective abstraction (p = .02) and an increase in personalization (p = .05). A significant link between RCI scores (outcome) and frequency of positive cognitive biases was found, suggesting that biases towards the positive might have a protective function in psychotherapy. Therapists may be attentive to changes in biased thinking across short-term dynamic psychotherapy for adjustment disorder. Therapists may foster the emergence of positive cognitive biases at mid-treatment for adjustment disorder. © 2017 The British Psychological Society.

  8. Obesity, the endocannabinoid system, and bias arising from pharmaceutical sponsorship.

    Directory of Open Access Journals (Sweden)

    John M McPartland

    Full Text Available Previous research has shown that academic physicians conflicted by funding from the pharmaceutical industry have corrupted evidence based medicine and helped enlarge the market for drugs. Physicians made pharmaceutical-friendly statements, engaged in disease mongering, and signed biased review articles ghost-authored by corporate employees. This paper tested the hypothesis that bias affects review articles regarding rimonabant, an anti-obesity drug that blocks the central cannabinoid receptor.A MEDLINE search was performed for rimonabant review articles, limited to articles authored by USA physicians who served as consultants for the company that manufactures rimonabant. Extracted articles were examined for industry-friendly bias, identified by three methods: analysis with a validated instrument for monitoring bias in continuing medical education (CME; analysis for bias defined as statements that ran contrary to external evidence; and a tally of misrepresentations about the endocannabinoid system. Eight review articles were identified, but only three disclosed authors' financial conflicts of interest, despite easily accessible information to the contrary. The Takhar CME bias instrument demonstrated statistically significant bias in all the review articles. Biased statements that were nearly identical reappeared in the articles, including disease mongering, exaggerating rimonabant's efficacy and safety, lack of criticisms regarding rimonabant clinical trials, and speculations about surrogate markers stated as facts. Distinctive and identical misrepresentations regarding the endocannabinoid system also reappeared in articles by different authors.The findings are characteristic of bias that arises from financial conflicts of interest, and suggestive of ghostwriting by a common author. Resolutions for this scenario are proposed.

  9. Obesity, the endocannabinoid system, and bias arising from pharmaceutical sponsorship.

    Science.gov (United States)

    McPartland, John M

    2009-01-01

    Previous research has shown that academic physicians conflicted by funding from the pharmaceutical industry have corrupted evidence based medicine and helped enlarge the market for drugs. Physicians made pharmaceutical-friendly statements, engaged in disease mongering, and signed biased review articles ghost-authored by corporate employees. This paper tested the hypothesis that bias affects review articles regarding rimonabant, an anti-obesity drug that blocks the central cannabinoid receptor. A MEDLINE search was performed for rimonabant review articles, limited to articles authored by USA physicians who served as consultants for the company that manufactures rimonabant. Extracted articles were examined for industry-friendly bias, identified by three methods: analysis with a validated instrument for monitoring bias in continuing medical education (CME); analysis for bias defined as statements that ran contrary to external evidence; and a tally of misrepresentations about the endocannabinoid system. Eight review articles were identified, but only three disclosed authors' financial conflicts of interest, despite easily accessible information to the contrary. The Takhar CME bias instrument demonstrated statistically significant bias in all the review articles. Biased statements that were nearly identical reappeared in the articles, including disease mongering, exaggerating rimonabant's efficacy and safety, lack of criticisms regarding rimonabant clinical trials, and speculations about surrogate markers stated as facts. Distinctive and identical misrepresentations regarding the endocannabinoid system also reappeared in articles by different authors. The findings are characteristic of bias that arises from financial conflicts of interest, and suggestive of ghostwriting by a common author. Resolutions for this scenario are proposed.

  10. A procedure for eliminating additive bias from cross-cultural survey data

    DEFF Research Database (Denmark)

    Scholderer, Joachim; Grunert, Klaus G.; Brunsø, Karen

    2005-01-01

    additive bias from cross-cultural data. The procedure involves four steps: (1) embed a potentially biased item in a factor-analytic measurement model, (2) test for the existence of additive bias between populations, (3) use the factor-analytic model to estimate the magnitude of the bias, and (4) replace......Measurement bias in cross-cultural surveys can seriously threaten the validity of hypothesis tests. Direct comparisons of means depend on the assumption that differences in observed variables reflect differences in the underlying constructs, and not an additive bias that may be caused by cultural...... differences in the understanding of item wording or response category labels. However, experience suggests that additive bias can be found more often than not. Based on the concept of partial measurement invariance (Byrne, Shavelson and Muthén 1989), the present paper develops a procedure for eliminating...

  11. Relativistic effects and primordial non-Gaussianity in the galaxy bias

    International Nuclear Information System (INIS)

    Bartolo, Nicola; Matarrese, Sabino; Riotto, Antonio

    2011-01-01

    When dealing with observables, one needs to generalize the bias relation between the observed galaxy fluctuation field to the underlying matter distribution in a gauge-invariant way. We provide such relation at second-order in perturbation theory adopting the local Eulerian bias model and starting from the observationally motivated uniform-redshift gauge. Our computation includes the presence of primordial non-Gaussianity. We show that large scale-dependent relativistic effects in the Eulerian bias arise independently from the presence of some primordial non-Gaussianity. Furthermore, the Eulerian bias inherits from the primordial non-Gaussianity not only a scale-dependence, but also a modulation with the angle of observation when sources with different biases are correlated

  12. Career conversations in vocational schools

    NARCIS (Netherlands)

    Mittendorff, K.M.; Brok, den P.J.; Beijaard, D.

    2010-01-01

    The purpose of this study was to examine career conversations between teachers and students in competence-based vocational education in the Netherlands. A total of 32 career conversations were observed and analysed with respect to four elements: content, teacher activities, student activities and

  13. Optimization theory for ballistic conversion

    NARCIS (Netherlands)

    Xie, Yanbo; Versluis, Michel; van den Berg, Albert; Eijkel, Jan C.T.

    2016-01-01

    The growing demand of renewable energy stimulates the exploration of new materials and methods for clean energy. We recently demonstrated a high efficiency and power density energy conversion mechanism by using jetted charged microdroplets, termed as ballistic energy conversion. Hereby, we model and

  14. The role of experience on techno-entrepreneurs’ decision making biases

    Directory of Open Access Journals (Sweden)

    Pouria Nouri

    2012-10-01

    Full Text Available Entrepreneurs are the driving force behind the prospect and growth of the societies. Sound and wise decisions pave the way for them to carry out these highly important functions. Entrepreneurs are to discover and exploit opportunities. Therefore, they must gather sufficient and pertinent information. Entrepreneurs, like most human beings face complex and ambiguous decision-making situations, not to mention their lack of time and source to gather and process the data. Under these circumstances, entrepreneurs are prone making biases decisions. There are many reasons identified for this entrepreneurial decision making biases, such as the high cost of rational decision making, limitations in information processing, differences in their styles and procedures, or information overload, environmental complexity, environmental uncertainty. These biases are neither totally harmful nor completely useful and have to be seen as natural human characteristics. What makes entrepreneurial decision-making biases important is their effects on the decisions and thus the outcome of the enterprises. Entrepreneurial decision-making biases, deliberate or unintentional can seal the fate of the enterprises, therefore studying them meticulously is crucial. Literature has shown that experience could be an effective factor in decision-making biases. In this paper, we try to find out the impact of experience in Iranian high tech entrepreneurs’ major decision-making biases by a qualitative approach. Finally, it was concluded that experience is influential in shaping overconfidence bias.

  15. Minimising bias in the forensic evaluation of suspicious paediatric injury.

    Science.gov (United States)

    Skellern, Catherine

    2015-08-01

    In the rules of evidence in all legal jurisdictions, medical experts are required to maintain objectivity when providing opinions. When interpreting medical evidence, doctors must recognise, acknowledge and manage uncertainties to ensure their evidence is reliable to legal decision-makers. Even in the forensic sciences such as DNA analysis, implicit bias has been shown to influence how results are interpreted from cognitive and contextual biases unconsciously operating. In cases involving allegations of child abuse there has been significant exposure in the media, popular magazines, legal journals and in the published medical literature debating the reliability of medical evidence given in these proceedings. In these cases judges have historically been critical of experts they perceived had sacrificed objectivity for advocacy by having an investment in a 'side'. This paper firstly discusses the issue of bias then describes types of cognitive biases identified from psychological research applied to forensic evidence including adversarial bias, context bias, confirmation bias and explains how terminology can influence the communication of opinion. It follows with previously published guidelines of how to reduce the risk of bias compromising objectivity in forensic practices then concludes with my own recommendations of practices that can be used by child protection paediatricians and within an organisation when conducting forensic evaluations of suspicious childhood injury to improve objectivity in formulation of opinion evidence. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  16. Peak-locking centroid bias in Shack-Hartmann wavefront sensing

    Science.gov (United States)

    Anugu, Narsireddy; Garcia, Paulo J. V.; Correia, Carlos M.

    2018-05-01

    Shack-Hartmann wavefront sensing relies on accurate spot centre measurement. Several algorithms were developed with this aim, mostly focused on precision, i.e. minimizing random errors. In the solar and extended scene community, the importance of the accuracy (bias error due to peak-locking, quantization, or sampling) of the centroid determination was identified and solutions proposed. But these solutions only allow partial bias corrections. To date, no systematic study of the bias error was conducted. This article bridges the gap by quantifying the bias error for different correlation peak-finding algorithms and types of sub-aperture images and by proposing a practical solution to minimize its effects. Four classes of sub-aperture images (point source, elongated laser guide star, crowded field, and solar extended scene) together with five types of peak-finding algorithms (1D parabola, the centre of gravity, Gaussian, 2D quadratic polynomial, and pyramid) are considered, in a variety of signal-to-noise conditions. The best performing peak-finding algorithm depends on the sub-aperture image type, but none is satisfactory to both bias and random errors. A practical solution is proposed that relies on the antisymmetric response of the bias to the sub-pixel position of the true centre. The solution decreases the bias by a factor of ˜7 to values of ≲ 0.02 pix. The computational cost is typically twice of current cross-correlation algorithms.

  17. Empirical Comparison of Publication Bias Tests in Meta-Analysis.

    Science.gov (United States)

    Lin, Lifeng; Chu, Haitao; Murad, Mohammad Hassan; Hong, Chuan; Qu, Zhiyong; Cole, Stephen R; Chen, Yong

    2018-04-16

    Decision makers rely on meta-analytic estimates to trade off benefits and harms. Publication bias impairs the validity and generalizability of such estimates. The performance of various statistical tests for publication bias has been largely compared using simulation studies and has not been systematically evaluated in empirical data. This study compares seven commonly used publication bias tests (i.e., Begg's rank test, trim-and-fill, Egger's, Tang's, Macaskill's, Deeks', and Peters' regression tests) based on 28,655 meta-analyses available in the Cochrane Library. Egger's regression test detected publication bias more frequently than other tests (15.7% in meta-analyses of binary outcomes and 13.5% in meta-analyses of non-binary outcomes). The proportion of statistically significant publication bias tests was greater for larger meta-analyses, especially for Begg's rank test and the trim-and-fill method. The agreement among Tang's, Macaskill's, Deeks', and Peters' regression tests for binary outcomes was moderately strong (most κ's were around 0.6). Tang's and Deeks' tests had fairly similar performance (κ > 0.9). The agreement among Begg's rank test, the trim-and-fill method, and Egger's regression test was weak or moderate (κ < 0.5). Given the relatively low agreement between many publication bias tests, meta-analysts should not rely on a single test and may apply multiple tests with various assumptions. Non-statistical approaches to evaluating publication bias (e.g., searching clinical trials registries, records of drug approving agencies, and scientific conference proceedings) remain essential.

  18. Conversion electrons in the SDC

    International Nuclear Information System (INIS)

    Wicklund, A.B.

    1991-01-01

    We summarize a preliminary analysis of the rates for conversion electrons in the SDC detector, relative to other interesting sources of prompt electrons. We have used Papageno V3.30, and other available NLO calculations to estimate inclusive rates in the central region (η less than 2.0), and we have cross checked these using CDF data at 1.8 TeV. We have considered three sources of ''isolated'' electrons, namely inclusive W/Z production; top quark (Mt=140); and QCD prompt photon production, followed by conversion in 10% XO. This value approximates the inner silicon detector at SDC. Additional conversions will occur in the outer tracking chamber, but the trigger and track reconstruction efficiency will be lower. We have also considered ''nonisolated'' leptons coming from inclusive bottom production, photon conversions resulting from π 0 ,η production in jets, and high pt hadrons faking electrons

  19. Hydrogen photoproduction by photoelectrochemical conversion

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    The water-splitting reaction by photoelectrochemical processes has gained much more attention than any of many reactions proposed for solar generation of energy-rich molecules (fuels). The conversion efficiency of the photosystem is the key factor. The higher the efficiency, the more economically feasible will be the conversion scheme. The conversion efficiency is a function of the semiconductor properties, light intensity, spectral quality, properties of the electrolyte, counterelectrode, cell configuration, etc. The semiconductor parameters include band gap, absorption coefficient and diffusion length. The area and material used for a counterelectrode are important when considering polarization losses in a two-electrode system. Besides, the stability problem is also a very important one to meet the requirement for practical applications. This paper reviews some important issues on photoelectrochemical generation of hydrogen by water splitting. It includes energy conversion efficiency, market assessment and cost goal, state of the technology, and future directions for research

  20. Deciding the fate of others: the cognitive underpinnings of racially biased juror decision making.

    Science.gov (United States)

    Kleider, Heather M; Knuycky, Leslie R; Cavrak, Sarah E

    2012-01-01

    In criminal law, jurors are supposed to ignore defendant race when considering factual matters of culpability. However, when judging the merits of a criminal case, jurors' ability (or inability) to avoid bias may affect verdicts. Fact-based decision making expend cognitive resources, while heuristic-based decisions (e.g., using criminal stereotypes) conserve resources. Here, we investigated whether differences in cognitive resources and prejudice attitudes about Blacks influenced trial outcomes. We tested the impact of working memory capacity (WMC), cognitive load, prejudice, and target race (Black, White) on penalties ascribed to fictional criminal defendants in ambiguous-fact cases. Results showed that when "loaded," prejudiced-low-WMC persons supported guilty verdicts with higher confidence more often for Black than White defendants. Conversely, regardless of WMC or prejudice attitude, participants penalized White defendants more often when not loaded. We suggest that cognitive resources and prejudice attitude influence fact-based decisions. Links to juror judgments and potential trial outcomes are discussed.

  1. evaluation of commercial FCC catalysts for hydrocarbon conversion. I. Physicochemical characterization and n-hexane conversion.

    NARCIS (Netherlands)

    Brait, A.; Brait, A.; Seshan, Kulathuiyer; Lercher, J.A.

    1998-01-01

    The physicochemical properties of six steam-stabilized, commercial FCC catalysts were compared in respect of their catalytic activity for n-hexane conversion. The conversion of n-hexane over these catalysts could be fully explained by three reaction pathways: protolytic cracking, protolytic

  2. Evaluation of bias-correction methods for ensemble streamflow volume forecasts

    Directory of Open Access Journals (Sweden)

    T. Hashino

    2007-01-01

    Full Text Available Ensemble prediction systems are used operationally to make probabilistic streamflow forecasts for seasonal time scales. However, hydrological models used for ensemble streamflow prediction often have simulation biases that degrade forecast quality and limit the operational usefulness of the forecasts. This study evaluates three bias-correction methods for ensemble streamflow volume forecasts. All three adjust the ensemble traces using a transformation derived with simulated and observed flows from a historical simulation. The quality of probabilistic forecasts issued when using the three bias-correction methods is evaluated using a distributions-oriented verification approach. Comparisons are made of retrospective forecasts of monthly flow volumes for a north-central United States basin (Des Moines River, Iowa, issued sequentially for each month over a 48-year record. The results show that all three bias-correction methods significantly improve forecast quality by eliminating unconditional biases and enhancing the potential skill. Still, subtle differences in the attributes of the bias-corrected forecasts have important implications for their use in operational decision-making. Diagnostic verification distinguishes these attributes in a context meaningful for decision-making, providing criteria to choose among bias-correction methods with comparable skill.

  3. Lessons Learned from Surveillance of Antimicrobial Susceptibilities of Pseudomonas aeruginosa at a Large Academic Medical Center

    Directory of Open Access Journals (Sweden)

    Brett H. Heintz

    2010-04-01

    Full Text Available This research report assessed the differences in resistance rates and antimicrobial usage-versus-susceptibility relationships of Pseudomonas aeruginosa found in various hospital patient care areas. A simplified case control study was also performed to identify patient-specific risk factors associated with cefepime-resistant P. aeruginosa isolates. Last, we determined the consequence of combining mucoid and non-mucoid derived antimicrobial susceptibilities of P. aeruginosa into hospital antibiograms. Overall, susceptibility rates remained lower in the intensive care units (ICUs compared to the non-ICU patient care areas, except for cefepime over the last time period. Cefepime utilization and antimicrobial-resistance rates among P. aeruginosa isolates had a significant relationship. Decreased meropenem exposure was associated with lower resistance rates relative to cefepime. Risk factors independently associated with cefepime-resistant P. aeruginosa were structural lung disease, ICU admission, recent third generation cephalosporin use, frequent hospital admission and non-urine isolates. Large and statistically significant differences were observed between non-mucoid and combined percent susceptibility data for aminoglycosides. To control antimicrobial resistance and optimize initial empiric antimicrobial therapy, antimicrobial susceptibility and utilization patterns in specific patient care areas should be monitored and risk factors for antimicrobial resistance should be assessed. Mucoid strains of P. aeruginosa should not be included into antimicrobial susceptibility data as this may underestimate activity of most antipseudomonal agents.

  4. Political Ideology and Perceptions of Bias Among University Faculty

    Directory of Open Access Journals (Sweden)

    Susan Bullers

    2010-10-01

    Full Text Available The goal of the study was to examine the political ideology and perceptions of bias among the faculty in a university in the southeast U.S.A. Findings regarding the overall dominance of a liberal political ideology as well as ideological differences among disciplines are consistent with previous research. Respondents did distinguish between political dominance and political bias and were relatively accurate in their perceptions of a liberal dominance. Reports of bias were much lower overall but all groups were more likely to report a bias against conservatives than against Liberal and Moderates. Reports of bias against conservatives were quite high among conservatives themselves (48.7%. Conservatives were more likely to report a need to conceal their political beliefs, while Moderates and Liberals were slightly more likely to report harassment or attacks for their political beliefs. The gender differences in political ideology show that women are significantly more likely to hold a liberal political ideology.

  5. Nonlinear vs. linear biasing in Trp-cage folding simulations

    Energy Technology Data Exchange (ETDEWEB)

    Spiwok, Vojtěch, E-mail: spiwokv@vscht.cz; Oborský, Pavel; Králová, Blanka [Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Technická 3, Prague 6 166 28 (Czech Republic); Pazúriková, Jana [Institute of Computer Science, Masaryk University, Botanická 554/68a, 602 00 Brno (Czech Republic); Křenek, Aleš [Institute of Computer Science, Masaryk University, Botanická 554/68a, 602 00 Brno (Czech Republic); Center CERIT-SC, Masaryk Univerzity, Šumavská 416/15, 602 00 Brno (Czech Republic)

    2015-03-21

    Biased simulations have great potential for the study of slow processes, including protein folding. Atomic motions in molecules are nonlinear, which suggests that simulations with enhanced sampling of collective motions traced by nonlinear dimensionality reduction methods may perform better than linear ones. In this study, we compare an unbiased folding simulation of the Trp-cage miniprotein with metadynamics simulations using both linear (principle component analysis) and nonlinear (Isomap) low dimensional embeddings as collective variables. Folding of the mini-protein was successfully simulated in 200 ns simulation with linear biasing and non-linear motion biasing. The folded state was correctly predicted as the free energy minimum in both simulations. We found that the advantage of linear motion biasing is that it can sample a larger conformational space, whereas the advantage of nonlinear motion biasing lies in slightly better resolution of the resulting free energy surface. In terms of sampling efficiency, both methods are comparable.

  6. Biased lineup instructions and face identification from video images.

    Science.gov (United States)

    Thompson, W Burt; Johnson, Jaime

    2008-01-01

    Previous eyewitness memory research has shown that biased lineup instructions reduce identification accuracy, primarily by increasing false-positive identifications in target-absent lineups. Because some attempts at identification do not rely on a witness's memory of the perpetrator but instead involve matching photos to images on surveillance video, the authors investigated the effects of biased instructions on identification accuracy in a matching task. In Experiment 1, biased instructions did not affect the overall accuracy of participants who used video images as an identification aid, but nearly all correct decisions occurred with target-present photo spreads. Both biased and unbiased instructions resulted in high false-positive rates. In Experiment 2, which focused on video-photo matching accuracy with target-absent photo spreads, unbiased instructions led to more correct responses (i.e., fewer false positives). These findings suggest that investigators should not relax precautions against biased instructions when people attempt to match photos to an unfamiliar person recorded on video.

  7. Effects of standard and explicit cognitive bias modification and computer-administered cognitive-behaviour therapy on cognitive biases and social anxiety.

    Science.gov (United States)

    Mobini, Sirous; Mackintosh, Bundy; Illingworth, Jo; Gega, Lina; Langdon, Peter; Hoppitt, Laura

    2014-06-01

    This study examines the effects of a single session of Cognitive Bias Modification to induce positive Interpretative bias (CBM-I) using standard or explicit instructions and an analogue of computer-administered CBT (c-CBT) program on modifying cognitive biases and social anxiety. A sample of 76 volunteers with social anxiety attended a research site. At both pre- and post-test, participants completed two computer-administered tests of interpretative and attentional biases and a self-report measure of social anxiety. Participants in the training conditions completed a single session of either standard or explicit CBM-I positive training and a c-CBT program. Participants in the Control (no training) condition completed a CBM-I neutral task matched the active CBM-I intervention in format and duration but did not encourage positive disambiguation of socially ambiguous or threatening scenarios. Participants in both CBM-I programs (either standard or explicit instructions) and the c-CBT condition exhibited more positive interpretations of ambiguous social scenarios at post-test and one-week follow-up as compared to the Control condition. Moreover, the results showed that CBM-I and c-CBT, to some extent, changed negative attention biases in a positive direction. Furthermore, the results showed that both CBM-I training conditions and c-CBT reduced social anxiety symptoms at one-week follow-up. This study used a single session of CBM-I training, however multi-sessions intervention might result in more endurable positive CBM-I changes. A computerised single session of CBM-I and an analogue of c-CBT program reduced negative interpretative biases and social anxiety. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. A test to identify judgement bias in mice

    NARCIS (Netherlands)

    Boleij, H.; van't Klooster, J.; Lavrijsen, M.; Kirchhoff, S.; Arndt, S.S.; Ohl, F.

    2012-01-01

    Emotional states are known to affect cognitive processes. For example highly anxious individuals interpret ambiguous stimuli more negatively than low anxious people, an effect called negative judgement bias. Recently, the measurement of judgement bias has been used to try and indicate emotional

  9. Pharmacological interventions to modulate attentional bias in addiction

    NARCIS (Netherlands)

    Luijten, M.; Field, M.; Franken, I.H.A.

    2014-01-01

    Attentional bias in substance-dependent patients is the tendency to automatically direct attention to substance-related cues in the environment. Preclinical models suggest that attentional bias emerges as a consequence of dopaminergic activity evoked by substance-related cues. The aim of the current

  10. Optimum biasing of integral equations in Monte Carlo calculations

    International Nuclear Information System (INIS)

    Hoogenboom, J.E.

    1979-01-01

    In solving integral equations and estimating average values with the Monte Carlo method, biasing functions may be used to reduce the variancee of the estimates. A simple derivation was used to prove the existence of a zero-variance collision estimator if a specific biasing function and survival probability are applied. This optimum biasing function is the same as that used for the well known zero-variance last-event estimator

  11. Procedures for Dealing with Optimism Bias in Transport Planning

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent; Glenting, Carsten; Rønnest, Arne Kvist

    of the document are to provide empirically based optimism bias up-lifts for selected reference classes of transport infrastructure projects and provide guidance on using the established uplifts to produce more realistic forecasts for the individual project's capital expenditures. Furthermore, the underlying...... causes and institutional context for optimism bias in British transport projects are discussed and some possibilities for reducing optimism bias in project preparation and decision-making are identified....

  12. The bias of weighted dark matter halos from peak theory

    CERN Document Server

    Verde, Licia; Simpson, Fergus; Alvarez-Gaume, Luis; Heavens, Alan; Matarrese, Sabino

    2014-01-01

    We give an analytical form for the weighted correlation function of peaks in a Gaussian random field. In a cosmological context, this approach strictly describes the formation bias and is the main result here. Nevertheless, we show its validity and applicability to the evolved cosmological density field and halo field, using Gaussian random field realisations and dark matter N-body numerical simulations. Using this result from peak theory we compute the bias of peaks (and dark matter halos) and show that it reproduces results from the simulations at the ${\\mathcal O}(10\\%)$ level. Our analytical formula for the bias predicts a scale-dependent bias with two characteristics: a broad band shape which, however, is most affected by the choice of weighting scheme and evolution bias, and a more robust, narrow feature localised at the BAO scale, an effect that is confirmed in simulations. This scale-dependent bias smooths the BAO feature but, conveniently, does not move it. We provide a simple analytic formula to des...

  13. Can decision biases improve insurance outcomes? An experiment on status quo bias in health insurance choice.

    Science.gov (United States)

    Krieger, Miriam; Felder, Stefan

    2013-06-19

    Rather than conforming to the assumption of perfect rationality in neoclassical economic theory, decision behavior has been shown to display a host of systematic biases. Properly understood, these patterns can be instrumentalized to improve outcomes in the public realm. We conducted a laboratory experiment to study whether decisions over health insurance policies are subject to status quo bias and, if so, whether experience mitigates this framing effect. Choices in two treatment groups with status quo defaults are compared to choices in a neutrally framed control group. A two-step design features sorting of subjects into the groups, allowing us to control for selection effects due to risk preferences. The results confirm the presence of a status quo bias in consumer choices over health insurance policies. However, this effect of the default framing does not persist as subjects repeat this decision in later periods of the experiment. Our results have implications for health care policy, for example suggesting that the use of non-binding defaults in health insurance can facilitate the spread of co-insurance policies and thereby help contain health care expenditure.

  14. Working memory biasing of visual perception without awareness.

    Science.gov (United States)

    Pan, Yi; Lin, Bingyuan; Zhao, Yajun; Soto, David

    2014-10-01

    Previous research has demonstrated that the contents of visual working memory can bias visual processing in favor of matching stimuli in the scene. However, the extent to which such top-down, memory-driven biasing of visual perception is contingent on conscious awareness remains unknown. Here we showed that conscious awareness of critical visual cues is dispensable for working memory to bias perceptual selection mechanisms. Using the procedure of continuous flash suppression, we demonstrated that "unseen" visual stimuli during interocular suppression can gain preferential access to awareness if they match the contents of visual working memory. Strikingly, the very same effect occurred even when the visual cue to be held in memory was rendered nonconscious by masking. Control experiments ruled out the alternative accounts of repetition priming and different detection criteria. We conclude that working memory biases of visual perception can operate in the absence of conscious awareness.

  15. Attentional bias for craving-related (chocolate) food cues.

    Science.gov (United States)

    Kemps, Eva; Tiggemann, Marika

    2009-12-01

    In this study, we investigated attentional biases for craving-related food cues. A pictorial dot probe task was used to assess selective attentional processing of one particular highly desired food, namely chocolate, relative to that of other highly desired foods. In Experiment 1, we examined biased processing of chocolate cues in habitual (trait) chocolate cravers, whereas in Experiment 2 we investigated the effect of experimentally induced (state) chocolate cravings on such processing. As predicted, habitual chocolate cravers (Experiment 1) and individuals in whom a craving for chocolate was temporarily induced (Experiment 2) showed speeded detection of probes replacing chocolate-related pictures, demonstrating an attentional bias for chocolate cues. Subsequent examination indicated that in both experiments the observed attentional biases stemmed from difficulty in disengaging attention from chocolate cues rather than from a shift of attention toward such cues. The findings have important theoretical and practical implications.

  16. Continual training of attentional bias in social anxiety.

    Science.gov (United States)

    Li, Songwei; Tan, Jieqing; Qian, Mingyi; Liu, Xinghua

    2008-08-01

    Using the dot-probe paradigm, it has been shown that high social anxiety is associated with an attentional bias toward negative information. In the present study, individuals with high social anxiety were divided into two groups randomly. One group was the attentional bias training group (Group T), and the other was the control group (Group C). For Group T, 7 days' continuous training of attentional bias was conducted using the dot-probe paradigm to make socially anxious individuals focus more on positive face pictures. The results showed that the training was effective in changing attentional bias in Group T. Scores of the Social Interaction Anxiety Scale (SIAS) in Group T were reduced compared to Group C, while the scores of Social Phobia Scale (SPS) and scores of Negative Evaluation Scale (FNE) showed no difference between the two groups, which suggested a limited reduction of social anxiety.

  17. Biased interpretation and memory in children with varying levels of spider fear.

    Science.gov (United States)

    Klein, Anke M; Titulaer, Geraldine; Simons, Carlijn; Allart, Esther; de Gier, Erwin; Bögels, Susan M; Becker, Eni S; Rinck, Mike

    2014-01-01

    This study investigated multiple cognitive biases in children simultaneously, to investigate whether spider-fearful children display an interpretation bias, a recall bias, and source monitoring errors, and whether these biases are specific for spider-related materials. Furthermore, the independent ability of these biases to predict spider fear was investigated. A total of 121 children filled out the Spider Anxiety and Disgust Screening for Children (SADS-C), and they performed an interpretation task, a memory task, and a Behavioural Assessment Test (BAT). As expected, a specific interpretation bias was found: Spider-fearful children showed more negative interpretations of ambiguous spider-related scenarios, but not of other scenarios. We also found specific source monitoring errors: Spider-fearful children made more fear-related source monitoring errors for the spider-related scenarios, but not for the other scenarios. Only limited support was found for a recall bias. Finally, interpretation bias, recall bias, and source monitoring errors predicted unique variance components of spider fear.

  18. Bias-dependent oscillatory electron transport of monatomic sulfur chains

    KAUST Repository

    Yu, Jing-Xin; Cheng, Yan; Sanvito, Stefano; Chen, Xiang-Rong

    2012-01-01

    The bias-dependent oscillatory electron transport of monatomic sulfur chains sandwiched between gold electrodes is investigated with density functional theory and non-equilibrium Green's function method. At zero bias, in contrast to the typical odd-even oscillations observed in most metallic chains, we find that the conductance oscillates with a period of four atoms. However, as the bias voltage is increased the current displays a two-atom periodicity. This emerges gradually, first for the longer chains and then, at voltages larger than 0.7 V, for lengths. The oscillatory behaviors are analyzed by the density of states and the energy-dependent and bias-dependent transmission coefficients. © 2012 American Institute of Physics.

  19. Bias-dependent oscillatory electron transport of monatomic sulfur chains

    KAUST Repository

    Yu, Jing-Xin

    2012-01-01

    The bias-dependent oscillatory electron transport of monatomic sulfur chains sandwiched between gold electrodes is investigated with density functional theory and non-equilibrium Green\\'s function method. At zero bias, in contrast to the typical odd-even oscillations observed in most metallic chains, we find that the conductance oscillates with a period of four atoms. However, as the bias voltage is increased the current displays a two-atom periodicity. This emerges gradually, first for the longer chains and then, at voltages larger than 0.7 V, for lengths. The oscillatory behaviors are analyzed by the density of states and the energy-dependent and bias-dependent transmission coefficients. © 2012 American Institute of Physics.

  20. Conversational sensing

    Science.gov (United States)

    Preece, Alun; Gwilliams, Chris; Parizas, Christos; Pizzocaro, Diego; Bakdash, Jonathan Z.; Braines, Dave

    2014-05-01

    Recent developments in sensing technologies, mobile devices and context-aware user interfaces have made it pos- sible to represent information fusion and situational awareness for Intelligence, Surveillance and Reconnaissance (ISR) activities as a conversational process among actors at or near the tactical edges of a network. Motivated by use cases in the domain of Company Intelligence Support Team (CoIST) tasks, this paper presents an approach to information collection, fusion and sense-making based on the use of natural language (NL) and controlled nat- ural language (CNL) to support richer forms of human-machine interaction. The approach uses a conversational protocol to facilitate a ow of collaborative messages from NL to CNL and back again in support of interactions such as: turning eyewitness reports from human observers into actionable information (from both soldier and civilian sources); fusing information from humans and physical sensors (with associated quality metadata); and assisting human analysts to make the best use of available sensing assets in an area of interest (governed by man- agement and security policies). CNL is used as a common formal knowledge representation for both machine and human agents to support reasoning, semantic information fusion and generation of rationale for inferences, in ways that remain transparent to human users. Examples are provided of various alternative styles for user feedback, including NL, CNL and graphical feedback. A pilot experiment with human subjects shows that a prototype conversational agent is able to gather usable CNL information from untrained human subjects.

  1. Girl child and gender bias.

    Science.gov (United States)

    Chowdhry, D P

    1995-01-01

    This article identifies gender bias against female children and youth in India. Gender bias is based on centuries-old religious beliefs and sayings from ancient times. Discrimination is reflected in denial or ignorance of female children's educational, health, nutrition, and recreational needs. Female infanticide and selective abortion of female fetuses are other forms of discrimination. The task of eliminating or reducing gender bias will involve legal, developmental, political, and administrative measures. Public awareness needs to be created. There is a need to reorient the education and health systems and to advocate for gender equality. The government of India set the following goals for the 1990s: to protect the survival of the girl child and practice safe motherhood; to develop the girl child in general; and to protect vulnerable girl children in different circumstances and in special groups. The Health Authorities should monitor the laws carefully to assure marriage after the minimum age, ban sex determination of the fetus, and monitor the health and nutrition of pre-school girls and nursing and pregnant mothers. Mothers need to be encouraged to breast feed, and to breast feed equally between genders. Every village and slum area needs a mini health center. Maternal mortality must decline. Primary health centers and hospitals need more women's wards. Education must be universally accessible. Enrollments should be increased by educating rural tribal and slum parents, reducing distances between home and school, making curriculum more relevant to girls, creating more female teachers, and providing facilities and incentives for meeting the needs of girl students. Supplementary income could be provided to families for sending girls to school. Recreational activities must be free of gender bias. Dowry, sati, and devdasi systems should be banned.

  2. The anterior bias in visual art: the case of images of animals.

    Science.gov (United States)

    Bertamini, Marco; Bennett, Kate M; Bode, Carole

    2011-11-01

    Composition is an important topic in visual art. The literature suggests a bias for objects on the right side (Levy, 1976) and two additional biases with respect to positioning of objects within a rectangular frame: a Centre bias and an Inward bias (Palmer, Gardner, & Wickens, 2008). We analysed images of animals from three datasets of works of art: two datasets were from artists well known for their portraits of animals (Bewick, Stubbs) and the third was a medieval bestiary. There was no overall displacement of the subject to the right or to the left of the picture. However, we found a bias consisting of more space in front compared to behind the animal, consistent with Palmer at al.'s findings and with their definition of an Inward bias. Because our animals never face towards the centre we use the term Anterior bias. In addition, we found a modulation of this bias on the basis of the facing direction of the animal, consisting of a stronger Anterior bias for left-facing animals. This asymmetry may originate from a combination of an Anterior bias and a Right bias. Finally, with respect to size we found that the size of the animals predicted the proportion of the picture occupied, an effect known as "canonical size".

  3. A review of cognitive biases in youth depression: attention, interpretation and memory.

    Science.gov (United States)

    Platt, Belinda; Waters, Allison M; Schulte-Koerne, Gerd; Engelmann, Lina; Salemink, Elske

    2017-04-01

    Depression is one of the most common mental health problems in childhood and adolescence. Although data consistently show it is associated with self-reported negative cognitive styles, less is known about the mechanisms underlying this relationship. Cognitive biases in attention, interpretation and memory represent plausible mechanisms and are known to characterise adult depression. We provide the first structured review of studies investigating the nature and causal role of cognitive biases in youth depression. Key questions are (i) do cognitive biases characterise youth depression? (ii) are cognitive biases a vulnerability factor for youth depression? and (iii) do cognitive biases play a causal role in youth depression? We find consistent evidence for positive associations between attention and interpretation biases and youth depression. Stronger biases in youth with an elevated risk of depression support cognitive-vulnerability models. Preliminary evidence from cognitive bias modification paradigms supports a causal role of attention and interpretation biases in youth depression but these paradigms require testing in clinical samples before they can be considered treatment tools. Studies of memory biases in youth samples have produced mixed findings and none have investigated the causal role of memory bias. We identify numerous areas for future research in this emerging field.

  4. Physicians and implicit bias: how doctors may unwittingly perpetuate health care disparities.

    Science.gov (United States)

    Chapman, Elizabeth N; Kaatz, Anna; Carnes, Molly

    2013-11-01

    Although the medical profession strives for equal treatment of all patients, disparities in health care are prevalent. Cultural stereotypes may not be consciously endorsed, but their mere existence influences how information about an individual is processed and leads to unintended biases in decision-making, so called "implicit bias". All of society is susceptible to these biases, including physicians. Research suggests that implicit bias may contribute to health care disparities by shaping physician behavior and producing differences in medical treatment along the lines of race, ethnicity, gender or other characteristics. We review the origins of implicit bias, cite research documenting the existence of implicit bias among physicians, and describe studies that demonstrate implicit bias in clinical decision-making. We then present the bias-reducing strategies of consciously taking patients' perspectives and intentionally focusing on individual patients' information apart from their social group. We conclude that the contribution of implicit bias to health care disparities could decrease if all physicians acknowledged their susceptibility to it, and deliberately practiced perspective-taking and individuation when providing patient care. We further conclude that increasing the number of African American/Black physicians could reduce the impact of implicit bias on health care disparities because they exhibit significantly less implicit race bias.

  5. Apparent directional selection by biased pleiotropic mutation.

    Science.gov (United States)

    Tanaka, Yoshinari

    2010-07-01

    Pleiotropic effects of deleterious mutations are considered to be among the factors responsible for genetic constraints on evolution by long-term directional selection acting on a quantitative trait. If pleiotropic phenotypic effects are biased in a particular direction, mutations generate apparent directional selection, which refers to the covariance between fitness and the trait owing to a linear association between the number of mutations possessed by individuals and the genotypic values of the trait. The present analysis has shown how the equilibrium mean value of the trait is determined by a balance between directional selection and biased pleiotropic mutations. Assuming that genes act additively both on the trait and on fitness, the total variance-standardized directional selection gradient was decomposed into apparent and true components. Experimental data on mutation bias from the bristle traits of Drosophila and life history traits of Daphnia suggest that apparent selection explains a small but significant fraction of directional selection pressure that is observed in nature; the data suggest that changes induced in a trait by biased pleiotropic mutation (i.e., by apparent directional selection) are easily compensated for by (true) directional selection.

  6. DC and AC biasing of a transition edge sensor microcalorimeter

    International Nuclear Information System (INIS)

    Cunningham, M.F.; Ullom, J.N.; Miyazaki, T.; Drury, O.; Loshak, A.; Berg, M.L. van den; Labov, S.E.

    2002-01-01

    We are developing AC-biased transition edge sensor (TES) microcalorimeters for use in large arrays with frequency-domain multiplexing. Using DC bias, we have achieved a resolution of 17 eV FWHM at 2.6 keV with a decay time of 90 μs and an effective detector diameter of 300 μm. We have successfully measured thermal pulses with a TES microcalorimeter operated with an AC bias. We present here preliminary results from a single pixel detector operated under DC and AC bias conditions

  7. Theory and experimental study of biased charge collector for measuring HPIB

    International Nuclear Information System (INIS)

    He Xiaoping; Wang Haiyang; Sun Jianfeng; Yang Hailiang; Qiu Aici; Tang Junping; Li Jingya; Li Hongyu

    2004-01-01

    Structure of the biased charge collector for measuring HPIB (High-power ion beam) is introduced in this paper. The inner charge propagation process of HPIB in the biased charge collector was simulated with KARAT PIC code. The simulation results indicated that charge was neutralized but current was not neutralized in the biased charge collector. The influence of biased voltage and aperture diameter were also simulated. A -800V biased voltage can meet the requirement for measuring 500 keV HPIB, and this is consistent with the experimental results

  8. Using artistic-narrative to stimulate reflection on physician bias.

    Science.gov (United States)

    Ross, Paula T; Lypson, Monica L

    2014-01-01

    Physician bias toward patients directly impacts patient care and health outcomes. However, too little research has been done investigating avenues to bring about self-awareness in this area to eliminate commonly held stereotypes that fuel physician bias. The purpose of this study was to explore the ways in which 2nd-year medical students' reflected on an artistic-narrative presentation given by a woman with sickle cell disease. A total of 320 2nd-year medical student essays were reviewed for content relevant to the artistic-narrative presentation. A total of 75 essays were identified and served as the data for this study. These 75 essays were analyzed using qualitative interpretive thematic content analysis to identify students' perceptions and reflections on culture in the healthcare environment and the patient-provider relationship. The analysis of the reflective essays revealed that this exercise helped students acknowledge physician bias in pain treatment, foster empathetic views toward patients as individuals, and recognize various ways in which biased beliefs can provide incite in healthcare disparities. These findings suggest that the combination of methods--art, narrative, and written reflection--helped students acknowledge their own bias as well as the ways in which taken-for-granted assumptions and biases can influence patient care.

  9. Leadership is a conversation.

    Science.gov (United States)

    Groysberg, Boris; Slind, Michael

    2012-06-01

    Globalization and new technologies have sharply reduced the efficacy of command-and-control management and its accompanying forms of corporate communication. In the course of a recent research project, the authors concluded that by talking with employees, rather than simply issuing orders, leaders can promote operational flexibility, employee engagement, and tight strategic alignment. Groysberg and Slind have identified four elements of organizational conversation that reflect the essential attributes of interpersonal conversation: intimacy, interactivity, inclusion, and intentionality. Intimacy shifts the focus from a top-down distribution of information to a bottom-up exchange of ideas. Organizational conversation is less corporate in tone and more casual. And it's less about issuing and taking orders than about asking and answering questions. Interactivity entails shunning the simplicity of monologue and embracing the unpredictable vitality of dialogue. Traditional one-way media-print and broadcast, in particular-give way to social media buttressed by social thinking. Inclusion turns employees into full-fledged conversation partners, entitling them to provide their own ideas, often on company channels. They can create content and act as brand ambassadors, thought leaders, and storytellers. Intentionality enables leaders and employees to derive strategically relevant action from the push and pull of discussion and debate.

  10. Sex Bias in Georgia High School Economics Textbooks.

    Science.gov (United States)

    Blankenship, Glen; Hahn, Carole L.

    1982-01-01

    Analyzes 17 secondary level economics textbooks for sex bias. All of the texts reviewed are on Georgia's approved textbook list. Without exception, each of the texts is guilty of sex bias, although to varying degrees. The method used in analyzing the texts is explained. (RM)

  11. Battling bias : Effects of training and training context

    NARCIS (Netherlands)

    Poos, J.M.; Bosch, K. van den; Janssen, C.P.

    2017-01-01

    This study investigates whether cognitive bias in judgment and decision making can be reduced by training, and whether the effects are affected by the nature of the training environment. Theory suggests that biases can be overcome by training in critical reflective thinking. In addition, applied

  12. Battling Bias: Effects of Training and Training Context

    NARCIS (Netherlands)

    Poos, Jackie; van den Bosch, Karel; Janssen, C.P.

    2017-01-01

    This study investigates whether cognitive bias in judgment and decision making can be reduced by training, and whether the effects are affected by the nature of the training environment. Theory suggests that biases can be overcome by training in critical reflective thinking. In addition, applied

  13. Response inhibition in motor conversion disorder.

    Science.gov (United States)

    Voon, Valerie; Ekanayake, Vindhya; Wiggs, Edythe; Kranick, Sarah; Ameli, Rezvan; Harrison, Neil A; Hallett, Mark

    2013-05-01

    Conversion disorders (CDs) are unexplained neurological symptoms presumed to be related to a psychological issue. Studies focusing on conversion paralysis have suggested potential impairments in motor initiation or execution. Here we studied CD patients with aberrant or excessive motor movements and focused on motor response inhibition. We also assessed cognitive measures in multiple domains. We compared 30 CD patients and 30 age-, sex-, and education-matched healthy volunteers on a motor response inhibition task (go/no go), along with verbal motor response inhibition (color-word interference) and measures of attention, sustained attention, processing speed, language, memory, visuospatial processing, and executive function including planning and verbal fluency. CD patients had greater impairments in commission errors on the go/no go task (P conversion. Patients with nonepileptic seizures, a different form of conversion disorder, are commonly reported to have lower IQ and multiple cognitive deficits. Our results point toward potential differences between conversion disorder subgroups. © 2013 Movement Disorder Society. Copyright © 2013 Movement Disorder Society.

  14. Catalytic Conversion of Carbohydrates

    DEFF Research Database (Denmark)

    Osmundsen, Christian Mårup

    a renewable route to aromatics. The conversion of biomass by high temperature processes is a desirable prospect due to the high volumetric production rates which can be achieved, and the ability of these types of processes to convert a wide range of substrates. Current processes however typically have rather...... with the production of commodity chemicals from the most abundantly available renewable source of carbon, carbohydrates. The production of alkyl lactates by the Lewis acid catalyzed conversion of hexoses is an interesting alternative to current fermentation based processes. A range of stannosilicates were...... to be an efficient initial conversion step in the utilization of biomass for chemicals production. The shift from an oil based chemical industry to one based on renewable resources is bound to happen sooner or later, however the environmental problems associated with the burning of fossil resources means...

  15. BIASED BEARINGS-ONIKY PARAMETER ESTIMATION FOR BISTATIC SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Xu Benlian; Wang Zhiquan

    2007-01-01

    According to the biased angles provided by the bistatic sensors,the necessary condition of observability and Cramer-Rao low bounds for the bistatic system are derived and analyzed,respectively.Additionally,a dual Kalman filter method is presented with the purpose of eliminating the effect of biased angles on the state variable estimation.Finally,Monte-Carlo simulations are conducted in the observable scenario.Simulation results show that the proposed theory holds true,and the dual Kalman filter method can estimate state variable and biased angles simultaneously.Furthermore,the estimated results can achieve their Cramer-Rao low bounds.

  16. Direct digital conversion detector technology

    Science.gov (United States)

    Mandl, William J.; Fedors, Richard

    1995-06-01

    Future imaging sensors for the aerospace and commercial video markets will depend on low cost, high speed analog-to-digital (A/D) conversion to efficiently process optical detector signals. Current A/D methods place a heavy burden on system resources, increase noise, and limit the throughput. This paper describes a unique method for incorporating A/D conversion right on the focal plane array. This concept is based on Sigma-Delta sampling, and makes optimum use of the active detector real estate. Combined with modern digital signal processors, such devices will significantly increase data rates off the focal plane. Early conversion to digital format will also decrease the signal susceptibility to noise, lowering the communications bit error rate. Computer modeling of this concept is described, along with results from several simulation runs. A potential application for direct digital conversion is also reviewed. Future uses for this technology could range from scientific instruments to remote sensors, telecommunications gear, medical diagnostic tools, and consumer products.

  17. Conversion of autoimmune hypothyroidism to hyperthyroidism

    OpenAIRE

    Furqan, Saira; Haque, Naeem-ul; Islam, Najmul

    2014-01-01

    Background Graves’ disease and Hashimoto’s thyroiditis are the two autoimmune spectrum of thyroid disease. Cases of conversion from hyperthyroidism to hypothyroidism have been reported but conversion from hypothyroidism to hyperthyroidism is very rare. Although such cases have been reported rarely in the past we are now seeing such conversions from hypothyroidism to hyperthyroidism more frequently in clinical practice. Case presentation We are reporting three cases of middle aged Asian female...

  18. A Developmental Neuroscience Perspective on Affect-Biased Attention

    Science.gov (United States)

    Morales, Santiago; Fu, Xiaoxue; Pérez-Edgar, Koraly E.

    2016-01-01

    There is growing interest regarding the impact of affect-biased attention on psychopathology. However, most of the research to date lacks a developmental approach. In the present review, we examine the role affect-biased attention plays in shaping socioemotional trajectories within a developmental neuroscience framework. We propose that affect-biased attention, particularly if stable and entrenched, acts as a developmental tether that helps sustain early socioemotional and behavioral profiles over time, placing some individuals on maladaptive developmental trajectories. Although most of the evidence is found in the anxiety literature, we suggest that these relations may operate across multiple domains of interest, including positive affect, externalizing behaviors, drug use, and eating behaviors. We also review the general mechanisms and neural correlates of affect-biased attention, as well as the current evidence for the co-development of attention and affect. Based on the reviewed literature, we propose a model that may help us better understand the nuances of affect-biased attention across development. The model may serve as a strong foundation for ongoing attempts to identify neurocognitive mechanisms and intervene with individuals at risk. Finally, we discuss open issues for future research that may help bridge existing gaps in the literature. PMID:27606972

  19. Effects of limiter biasing on the ATF torsatron

    International Nuclear Information System (INIS)

    Uckan, T.; Baylor, L.R.; Bell, J.D.; Bigelow, T.S.; England, A.C.; Harris, J.H.; Isler, R.C.; Jernigan, T.C.; Lyon, J.F.; Ma, C.H.; Mioduszewski, P.K.; Murakami, M.; Rasmussen, D.A.; Wilgen, J.B.; Aceto, S.C.; Zielinski, J.J.

    1992-09-01

    Positive limiter biasing on the currentless Advanced Toroidal Facility (ATF) torsatron produces a significant increase in the particle confinement with no improvement in the energy confinement. Experiments have been carried out in 1-T plasmas with ∼400 kill of electron cyclotron heating ECM. Two rail limiters located at the last closed flux surface (LCFS), one at the top and one at the bottom of the device, are biased at positive and negative potentials with respect to the vessel. When the limiters are positively biased at up to 300 V, the density increases sharply to the ECH cutoff value. At the same time, the H α radiation drops, indicating that the particle confinement improves. When the density is kept constant, the H α radiation is further reduced and there is almost no change in the plasma stored energy. Under these conditions, the density profile becomes peaked and the electric field becomes outward-pointing outside the LCFS and more negative inside the LCFS. In contrast, negative biasing yields some reduction of the density and stored energy at constant gas feed, and the plasma potential profile remains the same. Biasing has almost no effect on the intrinsic impurity levels in the plasma

  20. Hippocampal morphology mediates biased memories of chronic pain

    Science.gov (United States)

    Berger, Sara E.; Vachon-Presseau, Étienne; Abdullah, Taha B.; Baria, Alex T.; Schnitzer, Thomas J.; Apkarian, A. Vania

    2018-01-01

    Experiences and memories are often mismatched. While multiple studies have investigated psychological underpinnings of recall error with respect to emotional events, the neurobiological mechanisms underlying the divergence between experiences and memories remain relatively unexplored in the domain of chronic pain. Here we examined the discrepancy between experienced chronic low back pain (CBP) intensity (twice daily ratings) and remembered pain intensity (n = 48 subjects) relative to psychometric properties, hippocampus morphology, memory capabilities, and personality traits related to reward. 77% of CBP patients exaggerated remembered pain, which depended on their strongest experienced pain and their most recent mood rating. This bias persisted over nearly 1 year and was related to reward memory bias and loss aversion. Shape displacement of a specific region in the left posterior hippocampus mediated personality effects on pain memory bias, predicted pain memory bias in a validation CBP group (n = 21), and accounted for 55% of the variance of pain memory bias. In two independent groups (n = 20/group), morphology of this region was stable over time and unperturbed by the development of chronic pain. These results imply that a localized hippocampal circuit, and personality traits associated with reward processing, largely determine exaggeration of daily pain experiences in chronic pain patients. PMID:29080714