The Experts below are selected from a list of 53229 Experts worldwide ranked by ideXlab platform
Ronald Hübner - One of the best experts on this subject based on the ideXlab platform.
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Response-repetition costs in task switching : how they are modulated by previous-trial Response-Category activation
Acta psychologica, 2011Co-Authors: Kai Robin Grzyb, Ronald HübnerAbstract:A common finding is that there are Response-repetition (RR) costs under task switching. Moreover, when the stimulus on the previous trial was congruent then RR costs are usually larger than when it was incongruent. This effect of the previous trial has been explained by assuming that a Response Category is generally inhibited after the execution of its corresponding Response on the previous trial and that the amount of inhibition depends on the activation of the Response Category. However, up to now it was open which property of the Response-Category activation on the previous trial is crucial: the absolute activation of the correct Response Category or the activation difference between the alternative Response categories. To differentiate between these two possibilities we compared RR costs after congruent, neutral, and incongruent trials. In two experiments we found similar RR costs after congruent and neutral trials, whereas the RR costs were smaller after incongruent trials. These results support the hypothesis that the amount of Response inhibition is determined by the activation differences between the alternative Response categories on the previous trial.
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Effects of stimulus features and instruction on Response coding, selection, and inhibition : Evidence from repetition effects under task switching
Quarterly Journal of Experimental Psychology, 2008Co-Authors: Michel D. Druey, Ronald HübnerAbstract:The coding of stimuli and Responses is crucial for human behaviour. Here, we focused primarily on the Response codes (or Response categories). As a method, we applied a combined dual-task and task-switch paradigm with a fixed task-to-hand mapping. Usually, negative effects (i.e., costs) are observed for Response Category repetitions under task switching. However, in several previous studies it has been proposed that such repetition effects do not occur, if the stimulus categories (e.g., "odd" if digits have to be classified according to their parity feature) are unequivocally mapped to specific Responses. Our aim was to test this hypothesis. In the present experiments, we were able to distinguish between three different types of possible Response codes. The results show that the participants generally code their Responses according to abstract Response features (left/right, or index/middle finger). Moreover, the spatial codes were preferred over the finger-type codes even if the instructions stressed the latter. This preference, though, seemed to result from a stimulus-Response feature overlap, so that the spatial Response categories were primed by the respective stimulus features. If there was no such overlap, the instructions determined which type of Response code was involved in Response selection and inhibition.
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Multiple Response codes play specific roles in Response selection and inhibition under task switching
Psychological Research, 2008Co-Authors: Ronald Hübner, Michel D. DrueyAbstract:Several task-switch studies show that Response Category repetition is favorable on task repetition trials, but disadvantageous on task switch trials. In the present study we investigated how this interaction depends on the type and number of involved Response categories. In a dual-task number-categorization experiment, subjects had to respond to tasks T_1 and T_2 with one of the two fingers of their left and right hand, respectively. For one group of participants, the use of spatial Response categories, and for another group the use of finger-type categories was induced. It turned out that the interaction between task switching and Response Category repetition was clearly related to the induced Response categories, but at the same time, the spatial categories nevertheless also affected Response selection in the finger-type group. However, these two effects were additive. This shows that multiple Response codes can simultaneously be involved in Response selection, but that they affect performance differentially.
N.-c. Gorin - One of the best experts on this subject based on the ideXlab platform.
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Stem cells, multiorgan failure in radiation emergency medical preparedness: A U.S./European Consultation Workshop
Stem Cells, 2009Co-Authors: T.m. Fliedner, N.j. Chao, J.l. Bader, A. Boettger, C. Case Jr., J. Chute, D.l. Confer, A. Ganser, N.-c. Gorin, P. GourmelonAbstract:The concern of the public regarding terrorist actions involving nuclear emergencies resulted in the reopening of the discussion regarding the best ways to cope with the inevitable health impairments. Medical experts from the US and from Europe considered it of importance to harmonize at an international level the diagnostic and therapeutic approaches regarding the radiation-induced health impairments. The present contribution is the result of the first U.S./European Consultation Workshop addressing approaches to radiation emergency preparedness and assistance, which was held recently at Ulm University, Ulm, Germany. Discussions dealt with the assessment of the extent of damage after total body exposure and, in particular, the quantity and quality of the damage to the hematopoietic stem cell pool. Secondly, the pathogenesis of the multiorgan failure was considered because of the organ-to-organ interactions. Thirdly, approaches were considered to harmonize the "triage-methods" used on an international level using the "Response Category" approach as developed for the European Communities. These discussions lead to the conclusion that there is a strong need for continuing education of physicians, nurses, and support personnel to address the issues posed by the management of patients suffering from radiation syndromes. Finally, the discussions expressed the need for more international cooperation in research and development of more refined methods to treat patients with any type of radiation syndromes. © AlphaMed Press.
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stem cells multiorgan failure in radiation emergency medical preparedness a u s european consultation workshop
Stem Cells, 2009Co-Authors: Theodor M. Fliedner, N.j. Chao, J.l. Bader, A. Boettger, J. Chute, D.l. Confer, A. Ganser, Cullen Case, N.-c. GorinAbstract:The concern of the public regarding terrorist actions involving nuclear emergencies resulted in the reopening of the discussion regarding the best ways to cope with the inevitable health impairments. Medical experts from the US and from Europe considered it of importance to harmonize at an international level the diagnostic and therapeutic approaches regarding the radiation-induced health impairments. The present contribution is the result of the first U.S./European Consultation Workshop addressing approaches to radiation emergency preparedness and assistance, which was held recently at Ulm University, Ulm, Germany. Discussions dealt with the assessment of the extent of damage after total body exposure and, in particular, the quantity and quality of the damage to the hematopoietic stem cell pool. Secondly, the pathogenesis of the multiorgan failure was considered because of the organ-to-organ interactions. Thirdly, approaches were considered to harmonize the "triage-methods" used on an international level using the "Response Category" approach as developed for the European Communities. These discussions lead to the conclusion that there is a strong need for continuing education of physicians, nurses, and support personnel to address the issues posed by the management of patients suffering from radiation syndromes. Finally, the discussions expressed the need for more international cooperation in research and development of more refined methods to treat patients with any type of radiation syndromes.
Peter Hagell - One of the best experts on this subject based on the ideXlab platform.
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Measurement properties of the Swedish modified version of the Postural Assessment Scale for Stroke Patients (SwePASS) using Rasch analysis.
European Journal of Physical and Rehabilitation Medicine, 2017Co-Authors: Carina U. Persson, Annika Linder, Peter HagellAbstract:BACKGROUND: A previous small-sample (N.=150) Rasch analysis of the Swedish modified version of the Postural Assessment Scale for Stroke Patients (SwePASS) suggested problems regarding Response categories and redundant items that need confirmation in larger samples with more severe strokes. AIM: The aim of this study was to evaluate the measurement properties of the SwePASS in patients with acute stroke. DESIGN: A multicenter, cross-sectional study. SETTING: Two stroke units in Western Sweden. POPULATION: The study cohort included 250 consecutive inpatients undergoing rehabilitation after acute stroke. METHODS: The SwePASS assessments were performed once within the first four days after admission to the stroke units. The data were analyzed according to the Rasch measurement model regarding targeting, model fit, reliability, Response Category function, local dependence and differential item functioning. RESULTS: Postural control of 250 patients (median age, 76.5 years) was assessed with the SwePASS within median of two days after admission to the stroke units. The SwePASS covered a continuum of different levels of postural control, but had suboptimal targeting with insufficient representation of lower and higher levels of postural control. The reliability was high, the item fit statistics were generally acceptable and there was no differential item functioning by sex, age and stroke localization. However, Response categories did not function as expected for four of the 12 SwePASS items and five items exhibited local dependency. CONCLUSIONS: The SwePASS exhibited several promising measurement properties. To improve the scale, poor targeting, illogical Response categories and local dependency should be addressed. CLINICAL REHABILITATION IMPACT: The SwePASS provides valuable clinical information regarding postural control in the acute phase after stroke.
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stability of rating scale Response Category interpretations in neurological disorders
Acta Neurologica Scandinavica, 2013Co-Authors: Ida Knutsson, Peter Hagell, Karin SamuelsonAbstract:OBJECTIVES: Unambiguous use and interpretation of rating scale data assume that Response categories are interpreted and work as intended. This study investigated the stability of interpretations of commonly used patient-reported rating scale Response categories among people with neurological disorders. MATERIALS AND METHODS: Forty-six people with neurological disorders (26 men; mean age, 57; Parkinson's disease, 50%; multiple sclerosis, 41%) indicated their interpretation of 21 Response categories (representing frequencies, intensities and levels of agreement) on 100-mm visual analog scales (VAS) at two occasions, ≥2 weeks apart. Data were analyzed using intraclass correlation and weighted Kappa (ICC/Κw ; should be >0.4), mean/median differences, percentages agreement (PA), and the standard error of measurement (SEM). RESULTS: Most Response categories had ICC/Κw values <0.4. The overall average ICC/Κw was 0.279/0.294 (frequencies, 0.224/0.255; intensities, 0.265/0.251; levels of agreement, 0.362/0.376). The mean/median difference between time points across all 21 categories was 0.43/0.5 mm (mean/median absolute difference, 3.36/9 mm). The overall average PA and SEM were 6.5% and 16.1 mm, respectively. CONCLUSIONS: Stabilities in interpretations of patient-reported rating scale Response categories among people with neurological disorders were generally low. Categories expressing levels of agreement showed best results, suggesting that these may be preferable when appropriate with respect to the scale and its items. Future studies should consider Response Category interpretations in relation to various contexts. These observations suggest caution when interpreting raw rating scale data and argue for the use of modern rating scale methodologies such as the Rasch measurement model. (Less)
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Stability of rating scale Response Category interpretations in neurological disorders
Acta neurologica Scandinavica, 2013Co-Authors: Ida Knutsson, Karin Samuelson, Peter HagellAbstract:OBJECTIVES: Unambiguous use and interpretation of rating scale data assume that Response categories are interpreted and work as intended. This study investigated the stability of interpretations of commonly used patient-reported rating scale Response categories among people with neurological disorders. MATERIALS AND METHODS: Forty-six people with neurological disorders (26 men; mean age, 57; Parkinson's disease, 50%; multiple sclerosis, 41%) indicated their interpretation of 21 Response categories (representing frequencies, intensities and levels of agreement) on 100-mm visual analog scales (VAS) at two occasions, ≥2 weeks apart. Data were analyzed using intraclass correlation and weighted Kappa (ICC/Κw ; should be >0.4), mean/median differences, percentages agreement (PA), and the standard error of measurement (SEM). RESULTS: Most Response categories had ICC/Κw values
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Interpretation of Response categories in patient-reported rating scales: a controlled study among people with Parkinson's disease
Health and quality of life outcomes, 2010Co-Authors: Ida Knutsson, Helena Rydström, Jan Reimer, Per Nyberg, Peter HagellAbstract:Background: Unambiguous interpretation of ordered rating scale Response categories requires distinct meanings of Category labels. Also, summation of item Responses into total scores assumes equal intervals between categories. While studies have identified problems with rating scale Response Category functioning there is a paucity of empirical studies regarding how respondents interpret Response categories. We investigated the interpretation of commonly used rating scale Response categories and attempted to identify distinct and roughly equally spaced Response categories for patient-reported rating scales in Parkinson's disease (PD) and age-matched control subjects. Methods: Twenty-one rating scale Response categories representing frequency, intensity and level of agreement were presented in random order to 51 people with PD (36 men; mean age, 66 years) and 36 age-matched controls (14 men; mean age, 66). Respondents indicated their interpretation of each Category on 100-mm visual analog scales (VAS) anchored by Never - Always, Not at all - Extremely, and Totally disagree - Completely agree. VAS values were compared between groups, and Response categories with mean values and non-overlapping 95% CIs corresponding to equally spaced locations on the VAS line were sought to identify the best options for three-, four-, five-, and six-Category scales. Results: VAS values did not differ between the PD and control samples (P = 0.286) or according to educational level (P = 0.220), age (P = 0.220), self-reported physical functioning (P = 0.501) and mental health (P = 0.238), or (for the PD sample) PD duration (P = 0.213) or presence of dyskinesias (P = 0.212). Attempts to identify roughly equally spaced Response categories for three-, four-, five-, and six-Category scales were unsuccessful, as the 95% CIs of one or several of the identified Response categories failed to include the criterion values for equal distances. Conclusions: This study offers an evidence base for selecting more interpretable patient-reported rating scale Response categories. However, problems associated with raw rating scale data, primarily related to their ordinal structure also became apparent. This argues for the application of methodologies such as Rasch measurement. Rating scale Response categories need to be treated with rigour in the construction and analysis of rating scales.
J.l. Bader - One of the best experts on this subject based on the ideXlab platform.
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Stem cells, multiorgan failure in radiation emergency medical preparedness: A U.S./European Consultation Workshop
Stem Cells, 2009Co-Authors: T.m. Fliedner, N.j. Chao, J.l. Bader, A. Boettger, C. Case Jr., J. Chute, D.l. Confer, A. Ganser, N.-c. Gorin, P. GourmelonAbstract:The concern of the public regarding terrorist actions involving nuclear emergencies resulted in the reopening of the discussion regarding the best ways to cope with the inevitable health impairments. Medical experts from the US and from Europe considered it of importance to harmonize at an international level the diagnostic and therapeutic approaches regarding the radiation-induced health impairments. The present contribution is the result of the first U.S./European Consultation Workshop addressing approaches to radiation emergency preparedness and assistance, which was held recently at Ulm University, Ulm, Germany. Discussions dealt with the assessment of the extent of damage after total body exposure and, in particular, the quantity and quality of the damage to the hematopoietic stem cell pool. Secondly, the pathogenesis of the multiorgan failure was considered because of the organ-to-organ interactions. Thirdly, approaches were considered to harmonize the "triage-methods" used on an international level using the "Response Category" approach as developed for the European Communities. These discussions lead to the conclusion that there is a strong need for continuing education of physicians, nurses, and support personnel to address the issues posed by the management of patients suffering from radiation syndromes. Finally, the discussions expressed the need for more international cooperation in research and development of more refined methods to treat patients with any type of radiation syndromes. © AlphaMed Press.
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stem cells multiorgan failure in radiation emergency medical preparedness a u s european consultation workshop
Stem Cells, 2009Co-Authors: Theodor M. Fliedner, N.j. Chao, J.l. Bader, A. Boettger, J. Chute, D.l. Confer, A. Ganser, Cullen Case, N.-c. GorinAbstract:The concern of the public regarding terrorist actions involving nuclear emergencies resulted in the reopening of the discussion regarding the best ways to cope with the inevitable health impairments. Medical experts from the US and from Europe considered it of importance to harmonize at an international level the diagnostic and therapeutic approaches regarding the radiation-induced health impairments. The present contribution is the result of the first U.S./European Consultation Workshop addressing approaches to radiation emergency preparedness and assistance, which was held recently at Ulm University, Ulm, Germany. Discussions dealt with the assessment of the extent of damage after total body exposure and, in particular, the quantity and quality of the damage to the hematopoietic stem cell pool. Secondly, the pathogenesis of the multiorgan failure was considered because of the organ-to-organ interactions. Thirdly, approaches were considered to harmonize the "triage-methods" used on an international level using the "Response Category" approach as developed for the European Communities. These discussions lead to the conclusion that there is a strong need for continuing education of physicians, nurses, and support personnel to address the issues posed by the management of patients suffering from radiation syndromes. Finally, the discussions expressed the need for more international cooperation in research and development of more refined methods to treat patients with any type of radiation syndromes.
Parwinder S Grewal - One of the best experts on this subject based on the ideXlab platform.
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comparative in vivo gene expression of the closely related bacteria photorhabdus temperata and xenorhabdus koppenhoeferi upon infection of the same insect host rhizotrogus majalis
BMC Genomics, 2009Co-Authors: Ruisheng An, Srinand Sreevatsan, Parwinder S GrewalAbstract:Photorhabdus and Xenorhabdus are Gram-negative, phylogenetically related, enterobacteria, forming mutualism with the entomopathogenic nematodes Heterorhabditis and Steinernema, respectively. The mutualistic bacteria living in the intestines of the nematode infective juveniles are pathogenic to the insect upon release by the nematodes into the insect hemolymph. Such a switch needs activation of genes that promote bacterial virulence. We studied in vivo gene expression in Photorhabdus temperata and Xenorhabdus koppenhoeferi upon infection of the white grub Rhizotrogus majalis using selective capture of transcribed sequences technique. A total of 40 genes in P. temperata and 39 in X. koppenhoeferi were found to be upregulated in R. majalis hemolymph at 24 h post infection. Genomic presence or upregulation of these genes specific in either one of the bacterium was confirmed by the assay of comparative hybridization, and the changes of randomly selected genes were further validated by quantitative real-time PCR. The identified genes could be broadly divided into seven functional groups including cell surface structure, regulation, virulence and secretion, stress Response, intracellular metabolism, nutrient scavenging, and unknown. The two bacteria shared more genes in stress Response Category than any other functional group. More than 60% of the identified genes were uniquely induced in either bacterium suggesting vastly different molecular mechanisms of pathogenicity to the same insect host. In P. temperata lysR gene encoding transcriptional activator was induced, while genes yijC and rseA encoding transcriptional repressors were induced in X. koppenhoeferi. Lipopolysaccharide synthesis gene lpsE was induced in X. koppenhoeferi but not in P. temperata. Except tcaC and hemolysin related genes, other virulence genes were different between the two bacteria. Genes involved in TCA cycle were induced in P. temperata whereas those involved in glyoxylate pathway were induced in X. koppenhoeferi, suggesting differences in metabolism between the two bacteria in the same insect host. Upregulation of genes encoding different types of nutrient uptake systems further emphasized the differences in nutritional requirements of the two bacteria in the same insect host. Photorhabdus temperata displayed upregulation of genes encoding siderophore-dependent iron uptake system, but X. koppenhoeferi upregulated genes encoding siderophore-independent ion uptake system. Photorhabdus temperata induced genes for amino acid acquisition but X. koppenhoeferi upregulated malF gene, encoding a maltose uptake system. Further analyses identified possible mechanistic associations between the identified gene products in metabolic pathways, providing an interactive model of pathogenesis for each bacterium species. This study identifies set of genes induced in P. temperata and X. koppenhoeferi upon infection of R. majalis, and highlights differences in molecular features used by these two closely related bacteria to promote their pathogenicity in the same insect host.
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Comparative in vivo gene expression of the closely related bacteria Photorhabdus temperata and Xenorhabdus koppenhoeferi upon infection of the same insect host, Rhizotrogus majalis
BMC Genomics, 2009Co-Authors: Ruisheng An, Srinand Sreevatsan, Parwinder S GrewalAbstract:Background Photorhabdus and Xenorhabdus are Gram-negative, phylogenetically related, enterobacteria, forming mutualism with the entomopathogenic nematodes Heterorhabditis and Steinernema , respectively. The mutualistic bacteria living in the intestines of the nematode infective juveniles are pathogenic to the insect upon release by the nematodes into the insect hemolymph. Such a switch needs activation of genes that promote bacterial virulence. We studied in vivo gene expression in Photorhabdus temperata and Xenorhabdus koppenhoeferi upon infection of the white grub Rhizotrogus majalis using selective capture of transcribed sequences technique. Results A total of 40 genes in P. temperata and 39 in X. koppenhoeferi were found to be upregulated in R. majalis hemolymph at 24 h post infection. Genomic presence or upregulation of these genes specific in either one of the bacterium was confirmed by the assay of comparative hybridization, and the changes of randomly selected genes were further validated by quantitative real-time PCR. The identified genes could be broadly divided into seven functional groups including cell surface structure, regulation, virulence and secretion, stress Response, intracellular metabolism, nutrient scavenging, and unknown. The two bacteria shared more genes in stress Response Category than any other functional group. More than 60% of the identified genes were uniquely induced in either bacterium suggesting vastly different molecular mechanisms of pathogenicity to the same insect host. In P. temperata lysR gene encoding transcriptional activator was induced, while genes yijC and rseA encoding transcriptional repressors were induced in X. koppenhoeferi . Lipopolysaccharide synthesis gene lpsE was induced in X. koppenhoeferi but not in P. temperata . Except tcaC and hemolysin related genes, other virulence genes were different between the two bacteria. Genes involved in TCA cycle were induced in P. temperata whereas those involved in glyoxylate pathway were induced in X. koppenhoeferi , suggesting differences in metabolism between the two bacteria in the same insect host. Upregulation of genes encoding different types of nutrient uptake systems further emphasized the differences in nutritional requirements of the two bacteria in the same insect host. Photorhabdus temperata displayed upregulation of genes encoding siderophore-dependent iron uptake system, but X. koppenhoeferi upregulated genes encoding siderophore-independent ion uptake system. Photorhabdus temperata induced genes for amino acid acquisition but X. koppenhoeferi upregulated malF gene, encoding a maltose uptake system. Further analyses identified possible mechanistic associations between the identified gene products in metabolic pathways, providing an interactive model of pathogenesis for each bacterium species. Conclusion This study identifies set of genes induced in P. temperata and X. koppenhoeferi upon infection of R. majalis , and highlights differences in molecular features used by these two closely related bacteria to promote their pathogenicity in the same insect host.