Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 39 )

2018 ( 244 )

2017 ( 245 )

2016 ( 338 )

Custom range...

Search Results: 1 - 10 of 191249 matches for " D. Gottschall "
All listed articles are free for downloading (OA Articles)
Page 1 /191249
Display every page Item
Item difficulty of multiple choice tests dependant on different item response formats – An experiment in fundamental research on psychological assessment
Psychology Science , 2007,
Abstract: Multiple choice response formats are problematical as an item is often scored as solved simply because the test-taker is a lucky guesser. Instead of applying pertinent IRT models which take guessing effects into account, a pragmatic approach of re-conceptualizing multiple choice response formats to reduce the chance of lucky guessing is considered. This paper compares the free response format with two different multiple choice formats. A common multiple choice format with a single correct response option and five distractors (“1 of 6”) is used, as well as a multiple choice format with five response options, of which any number of the five is correct and the item is only scored as mastered if all the correct response options and none of the wrong ones are marked (“x of 5”). An experiment was designed, using pairs of items with exactly the same content but different response formats. 173 test-takers were randomly assigned to two test booklets of 150 items altogether. Rasch model analyses adduced a fitting item pool, after the deletion of 39 items. The resulting item difficulty parameters were used for the comparison of the different formats. The multiple choice format “1 of 6” differs significantly from “x of 5”, with a relative effect of 1.63, while the multiple choice format “x of 5” does not significantly differ from the free response format. Therefore, the lower degree of difficulty of items with the “1 of 6” multiple choice format is an indicator of relevant guessing effects. In contrast the “x of 5” multiple choice format can be seen as an appropriate substitute for free response format.
Altered synaptic marker abundance in the hippocampal stratum oriens of Ts65Dn mice is associated with exuberant expression of versican
Matthew D Howell,Paul E Gottschall
ASN Neuro , 2012, DOI: 10.1042/an20110037
Abstract: DS (Down syndrome), resulting from trisomy of chromosome 21, is the most common cause of genetic mental retardation; however, the molecular mechanisms underlying the cognitive deficits are poorly understood. Growing data indicate that changes in abundance or type of CSPGs (chondroitin sulfate proteoglycans) in the ECM (extracellular matrix) can influence synaptic structure and plasticity. The purpose of this study was to identify changes in synaptic structure in the hippocampus in a model of DS, the Ts65Dn mouse, and to determine the relationship to proteoglycan abundance and/or cleavage and cognitive disability. We measured synaptic proteins by ELISA and changes in lectican expression and processing in the hippocampus of young and old Ts65Dn mice and LMCs (littermate controls). In young (5 months old) Ts65Dn hippocampal extracts, we found a significant increase in the postsynaptic protein PSD-95 (postsynaptic density 95) compared with LMCs. In aged (20 months old) Ts65Dn hippocampus, this increase was localized to hippocampal stratum oriens extracts compared with LMCs. Aged Ts65Dn mice exhibited impaired hippocampal-dependent spatial learning and memory in the RAWM (radial-arm water maze) and a marked increase in levels of the lectican versican V2 in stratum oriens that correlated with the number of errors made in the final RAWM block. Ts65Dn stratum oriens PNNs (perineuronal nets), an extension of the ECM enveloping mostly inhibitory interneurons, were dispersed over a larger area compared with LMC mice. Taken together, these data suggest a possible association with alterations in the ECM and inhibitory neurotransmission in the Ts65Dn hippocampus which could contribute to cognitive deficits.
Selective Decline of Synaptic Protein Levels in the Frontal Cortex of Female Mice Deficient in the Extracellular Metalloproteinase ADAMTS1
Matthew D. Howell, Antoni X. Torres-Collado, M. Luisa Iruela-Arispe, Paul E. Gottschall
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0047226
Abstract: The chondroitin sulfate-bearing proteoglycans, also known as lecticans, are a major component of the extracellular matrix (ECM) in the central nervous system and regulate neural plasticity. Growing evidence indicates that endogenous, extracellular metalloproteinases that cleave lecticans mediate neural plasticity by altering the structure of ECM aggregates. The bulk of this in vivo data examined the matrix metalloproteinases, but another metalloproteinase family that cleaves lecticans, a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS), modulates structural plasticity in vitro, although few in vivo studies have tested this concept. Thus, the purpose of this study was to examine the neurological phenotype of a mouse deficient in ADAMTS1. Adamts1 mRNA was absent in the ADAMTS1 null mouse frontal cortex, but there was no change in the abundance or proteolytic processing of the prominent lecticans brevican and versican V2. However, there was a marked increase in the perinatal lectican neurocan in juvenile ADAMTS1 null female frontal cortex. More prominently, there were declines in synaptic protein levels in the ADAMTS1 null female, but not male, frontal cortex beginning at postnatal day 28. These synaptic marker declines did not affect learning or memory in the adult female ADAMTS1 null mice when tested with the radial-arm water maze. These results indicate that in vivo Adamts1 knockout leads to sexual dimorphism in frontal cortex synaptic protein levels. Since changes in lectican abundance and proteolytic processing did not accompany the synaptic protein declines, ADAMTS1 may play a nonproteolytic role in regulating neural plasticity.
Neandertal Humeri May Reflect Adaptation to Scraping Tasks, but Not Spear Thrusting
Colin N. Shaw, Cory L. Hofmann, Michael D. Petraglia, Jay T. Stock, Jinger S. Gottschall
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0040349
Abstract: Unique compared with recent and prehistoric Homo sapiens, Neandertal humeri are characterised by a pronounced right-dominant bilateral strength asymmetry and an anteroposteriorly strengthened diaphyseal shape. Remodeling in response to asymmetric forces imposed during regular underhanded spear thrusting is the most influential explanatory hypothesis. The core tenet of the “Spear Thrusting Hypothesis”, that underhand thrusting requires greater muscle activity on the right side of the body compared to the left, remains untested. It is unclear whether alternative subsistence behaviours, such as hide processing, might better explain this morphology. To test this, electromyography was used to measure muscle activity at the primary movers of the humerus (pectoralis major (PM), anterior (AD) and posterior deltoid (PD)) during three distinct spear-thrusting tasks and four separate scraping tasks. Contrary to predictions, maximum muscle activity (MAX) and total muscle activity (TOT) were significantly higher (all values, p<.05) at the left (non-dominant) AD, PD and PM compared to the right side of the body during spear thrusting tasks. Thus, the muscle activity required during underhanded spearing tasks does not lend itself to explaining the pronounced right dominant strength asymmetry found in Neandertal humeri. In contrast, during the performance of all three unimanual scraping tasks, right side MAX and TOT were significantly greater at the AD (all values, p<.01) and PM (all values, p<.02) compared to the left. The consistency of the results provides evidence that scraping activities, such as hide preparation, may be a key behaviour in determining the unusual pattern of Neandertal arm morphology. Overall, these results yield important insight into the Neandertal behavioural repertoire that aided survival throughout Pleistocene Eurasia.
Diabetes e implante de stents coronarianos: experiência de um centro de referência em cardiologia intervencionista
Schaan, Beatriz D.;Quadros, Alexandre;Sarmento-Leite, Rogério;Gottschall, Carlos A.M.;
Arquivos Brasileiros de Endocrinologia & Metabologia , 2006, DOI: 10.1590/S0004-27302006000100006
Abstract: we evaluated the influence of diabetes mellitus (dm) on clinical outcomes in patients with coronary artery disease treated with stent implantation. between 1996 and 2000, 934 stents were implanted in 893 patients in our institution; 23% of them had dm. clinical and angiographic characteristics and clinical outcomes of the patients with and without dm were prospectively included in a computerized database. diabetics were older (61.5 ± 10 vs. 59.8 ± 11 years; p= 0.04) and had a higher prevalence of hypertension (69% vs. 62%; p= 0.09). the procedural clinical success rate (successful coronary stenting with residual stenosis < 30%, timi 3 flow and no in-hospital adverse clinical event) was lower in the diabetic group (88% vs. 92%; p= 0.05). in the 1-year follow up, diabetic patients showed higher rates of new target vessel revascularization (12.3% vs. 8%; p= 0.06), death (5.4% vs. 2.5%; p= 0.03) and major adverse cardiovascular events (mace, new angioplasty, surgery, acute myocardial infarction or death: 16.3% vs. 9.3%; p= 0.003). diabetes was independently associated to 1-year mace on multivariate analysis (or: 2.00; ic: 1.25-3.24; p= 0.004). we concluded that dm is associated with higher complication and restenosis rates and a higher risk of long-term major cardiovascular events in patients treated with coronary stent implantation.
Diabetes e implante de stents coronarianos: experiência de um centro de referência em cardiologia intervencionista
Schaan Beatriz D.,Quadros Alexandre,Sarmento-Leite Rogério,Gottschall Carlos A.M.
Arquivos Brasileiros de Endocrinologia & Metabologia , 2006,
Abstract: Nosso objetivo foi avaliar a influência do diabetes mellitus (DM) na evolu o clínica de pacientes com doen a arterial coronariana tratada com implante de stents. Foram implantados 934 stents em 893 pacientes em nossa institui o de 1996 a 2000; 23% destes apresentavam DM. Características clínicas, angiográficas e desfechos clínicos dos pacientes com e sem DM foram prospectivamente incluídos em banco de dados computadorizado. O grupo DM tinha maior idade (61,5 ? 10 vs. 59,8 ? 11 anos; p= 0,04) e prevalência de hipertens o arterial (69% vs. 62%; p= 0,09). A taxa de sucesso clínico do procedimento (estenose residual < 30%, fluxo TIMI 3, ausência de eventos clínicos adversos na interna o) foi menor nos pacientes com DM (88% vs. 92%; p= 0,05). Em 1 ano, os pacientes com DM apresentaram maiores taxas de revasculariza o do vaso-alvo (12,3% vs. 8%; p= 0,06), óbitos (5,4% vs. 2,5%; p= 0,03) e eventos cardiovasculares maiores (ECVM; nova angioplastia, cirurgia, infarto agudo do miocárdio ou óbito: 16,3% vs. 9,3%; p= 0,003). A presen a de DM foi independentemente associada a ECVM na análise multivariada (OR: 2,00; IC: 1,25-3,24; p= 0,004). Concluímos que o DM associa-se a aumento do risco de complica es intra-hospitalares, re-estenose e eventos cardiovasculares maiores em pacientes submetidos ao implante de stents coronarianos.
1929-2009: 80 Anos de cateterismo cardíaco - uma história dentro da história
Gottschall, Carlos A. M.;
Revista Brasileira de Cardiologia Invasiva , 2009, DOI: 10.1590/S2179-83972009000200019
Abstract: in this article, the author reviews the early steps of the cardiac catheterization, the development of this term and the first direct experimental records of the heart movements in the end of the 19th century. the circumstances regarding the inauguration of cardiac catheterization in human beings by werner forrsmann eighty years ago and the application of the method in clinical medicine by cournand, richards and baldwin between 1940 and 1950 are highlighted. the development of right and left cardiac catheterization, the facts that enabled the development of angiocardiography and the expansion of its indications after 1960 are reported. the author also reports how charles dotter created the concept of peripheral and coronary transluminal angioplasty and magnifies the contributions of andreas gruentzig and richard myler, as well as fundamental achievements such as stents, which led to an extraordinary improvement of this procedure which has been the basis of interventional cardiology. based on the point of view of one who has experienced a major part of this history, he points out the importance of this method for the development of the experimental, clinical and therapeutical cardiology in the last three decades.
Mário Rigatto, meu mestre (28/12/1928 17/1/2000)
Gottschall Carlos A. M.
Arquivos Brasileiros de Cardiologia , 2000,
Ventriculectomia esquerda parcial. Paradigmas esquecidos
Gottschall Carlos A. M.
Arquivos Brasileiros de Cardiologia , 1998,
The greatest medical discovery of the millennium (Fundamental steps to the understanding of cardiac performance)
Gottschall Carlos Antonio Mascia
Arquivos Brasileiros de Cardiologia , 1999,
Page 1 /191249
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.