378 research outputs found

    Coronary flow reserve in stress-echo lab. From pathophysiologic toy to diagnostic tool

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    The assessment of coronary flow reserve by transthoracic echocardiography has recently been introduced into clinical practice with gratifying results for the diagnosis of left anterior descending artery disease simultaneously reported by several independent laboratories. This technological novelty is changing the practice of stress echo for 3 main reasons. First, adding coronary flow reserve to regional wall motion allows us to have – in the same sitting – high specificity (regional wall motion) and a high sensitivity (coronary flow reserve) diagnostic marker, with an obvious improvement in overall diagnostic accuracy. Second, the technicalities of coronary flow reserve shift the balance of stress choice in favour of vasodilators, which are a more robust hyperemic stress and are substantially easier to perform with dual imaging than dobutamine or exercise. Third, the coronary flow reserve adds a quantitative support to the exquisitely qualitative assessment of wall motion analysis, thereby facilitating the communication of stress echo results to the cardiological world outside the echo lab. The next challenges involve the need to expand the exploration of coronary flow reserve to the right and circumflex coronary artery and to prove the additional prognostic value – if any – of coronary flow reserve over regional wall motion analysis, which remains the cornerstone of clinically-driven diagnosis in the stress echo lab

    Students today, between Facebook, Google and Metacognition. Ideas to innovate in Higher Education

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    [ES] En los estudios superiores, al igual que en los demás contextos educativos, no basta con adquirir una serie de conocimientos, es indispensable reflexionar sobre los propios procesos cognitivos para tomar decisiones autónomas y fundamentadas respecto de los aprendizajes. Aprender va mucho más allá de las cuestiones cognitivas, las emociones puestas en juego y las posibilidades de reflexionar respecto de los aprendizajes resultan decisivas en los complejos procesos de construcción de conocimientos. El objetivo del estudio es analizar aspectos metacognitivos vinculados al aprendizaje académico de estudiantes de primer año del Profesorado en Educación Inicial de la Universidad Nacional de Río Cuarto y del Instituto Superior María Inmaculada (Argentina). En la primera parte de la investigación, los estudiantes respondieron a un cuestionario general referido a prácticas y hábitos de estudio y a un inventario de patrones de aprendizaje: ILS (Vermunt, 1998). Luego, se realizaron entrevistas grupales con los estudiantes con el propósito de conocer diferentes puntos de vista respecto de las prácticas de estudio, aprendizaje y enseñanza en la educación superior. Los resultados muestran que la mayoría de los participantes requieren de regulaciones externas para desarrollar los procesos de aprendizaje. Se observan ciertas dificultades en la autorregulación de los procesos de lectura, escritura y en el estudio en general. Se propone desarrollar estrategias innovadoras que promuevan en los estudiantes prácticas reflexivas y metacognitivas respecto de los aprendizajes en contextos académicos.[ES] In college, as in other educational contexts, not enough to acquire a body of knowledge, it is essential to think about the cognitive processes to make independent and informed decisions regarding learning. Learning goes beyond cognitive issues, emotions and the posssibilities of think over of learning are critical in the complex processes of knowledge construction. The purpose of the study is to analyze metacognitive aspects related to academic learning on first year students of Kindergarten Teacher at the Universidad Nacional de Río Cuarto and Intituto Superior María Inmaculada (Argentina). At the first part of the research, students answered a general questionnaire on practices and habits of study and an inventory of learning patterns: ILS (Vermunt, 1998). Then, we conducted group interviews with students in order to acknowledge different views regarding the study practices, learning and teaching in contexts of higher education. The results show that most of students require external regulations to develop learning processes. We observe some difficulties in self-regulation of reading processes, writing and study in general. It is proposed to develop innovative strategies to promote thoughtful and metacognitive practices in students concerning learning in academic contexts.Elisondo, R.; De La Barrera, ML.; Rigo, DY.; Kowszyk, DI.; Fagotti Kucharski, E.; Ricetti, A.; Siracusa, M. (2016). Estudiantes hoy, entre Facebook, Google y Metacognición. Ideas para innovar en la Educación Superior. REDU. Revista de Docencia Universitaria. 14(1):225-244. doi:10.4995/redu.2016.5800.SWORD22524414

    Vitamin-V: Virtual Environment and Tool-boxing for Trustworthy Development of RISC-V based Cloud Services

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    Vitamin-V is a 2023-2025 Horizon Europe project that aims to develop a complete RISC-V open-source software stack for cloud services with comparable performance to the cloud-dominant x86 counterpart and a powerful virtual execution environment for software development, validation, verification, and test that considers the relevant RISC-V ISA extensions for cloud deployment

    Feedback-control of quantum systems using continuous state-estimation

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    We present a formulation of feedback in quantum systems in which the best estimates of the dynamical variables are obtained continuously from the measurement record, and fed back to control the system. We apply this method to the problem of cooling and confining a single quantum degree of freedom, and compare it to current schemes in which the measurement signal is fed back directly in the manner usually considered in existing treatments of quantum feedback. Direct feedback may be combined with feedback by estimation, and the resulting combination, performed on a linear system, is closely analogous to classical LQG control theory with residual feedback.Comment: 12 pages, multicol revtex, revised and extende

    Spanish validation of Bad Sobernheim Stress Questionnaire (BSSQ (brace).es) for adolescents with braces

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    <p>Abstract</p> <p>Background</p> <p>As a result of scientific and medical professionals gaining interest in Stress and Health Related Quality of Life (HRQL), the aim of our research is, thus, to validate into Spanish the German questionnaire <b>Bad Sobernheim Stress Questionnaire (BSSQ) (mit Korsett)</b>, for adolescents wearing braces.</p> <p>Methods</p> <p>The methodology used adheres to literature on trans-cultural adaptation by doing a translation and a back translation; it involved 35 adolescents, ages ranging between 10 and 16, with Adolescent Idiopathic Scoliosis (AIS) and wearing the same kind of brace (Rigo System Chêneau Brace). The materials used were a socio-demographics data questionnaire, the SRS-22 and the Spanish version of BSSQ(brace).es. The statistical analysis calculated the reliability (test-retest reliability and internal consistency) and the validity (convergent and construct validity) of the BSSQ (brace).es.</p> <p>Results</p> <p>BSSQ(brace).es is reliable because of its satisfactory internal consistency (Cronbach's alpha coefficient was 0.809, p < 0.001) and temporal stability (test-retest method with a Pearson correlation coefficient of 0.902 (p < 0.01)).</p> <p>It demonstrated convergent validity with SRS-22 since the Pearson correlation coefficient was 0.656 (p < 0.01). By undertaking an Exploratory Principal Components Analysis, a latent structure was found based on two Components which explicate the variance at 60.8%.</p> <p>Conclusions</p> <p>BSSQ (brace).es is reliable and valid and can be used with Spanish adolescents to assess the stress level caused by the brace.</p

    "Rehabilitation schools for scoliosis" thematic series: describing the methods and results

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    The Scoliosis Rehabilitation model begins with the correct diagnosis and evaluation of the patient, to make treatment decisions oriented to the patient. The treatment is based on observation, education, scoliosis specific exercises, and bracing. The state of research in the field of conservative treatment is insufficient. There is some evidence supporting scoliosis specific exercises as a part of the rehabilitation treatment, however, the evidence is poor and the different methods are not known by most of the scientific community. The only way to improve the knowledge and understanding of the different physiotherapy methodologies (specific exercises), integrated into the whole rehabilitation program, is to establish a single and comprehensive source of information about it. This is what the SCOLIOSIS Journal is going to do through the "Rehabilitation Schools for Scoliosis" Thematic Series, where technical papers coming from the different schools will be published

    Dobutamine stress echocardiography for assessing the role of dynamic intraventricular obstruction in left ventricular ballooning syndrome

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    <p>Abstract</p> <p>Background</p> <p>Dynamic intraventricular obstruction has been observed in patients with left ventricular ballooning syndrome (LVBS) and has been hypothesized as a possible mechanism of the syndrome. The aim of this study was to assess the prevalence and significance of dynamic intraventricular obstruction in patients with LVBS.</p> <p>Methods and Results</p> <p>Dobutamine stress echocardiography was carried out in 22 patients with LVBS (82% apical), all women, aged 68 ± 9 years. At baseline 1 patient had a > 30 mmHg LV gradient; during stress a LV gradient > 30 mm Hg developed in 6/21 patients (28%) and was caused by systolic anterior motion of the mitral valve in the 3 patients with severe gradient (mean 116 ± 29 mmHg), who developed mitral regurgitation and impaired apical wall motion and by obstruction at mid-ventricular level in the other 3 with a moderate gradient (mean 46 ± 16 mmHg). Compared with patients without obstruction those with obstruction had a greater mean septal thickness (11.6 ± .6 vs 9.8. ± 3, p < .01), a higher prevalence of septal hypertrophy (71% vs 7%, p < .005) and a higher peak wall motion score index (1.62 ± .4 vs 1.08 ± .4, p < .01).</p> <p>Conclusion</p> <p>Spontaneous or dobutamine-induced dynamic LV obstruction is documented in 32% of patients with LVBS, is correlated with the presence of septal hypertrophy and may play a role in the development of LVBS in this subset of patients. In those without septal hypertrophy a dynamic obstruction is rarely induced with dobutamine and is unlikely to be a major pathogenetic factor of the syndrome.</p

    CXCL12 and [N33A]CXCL12 in 5637 and HeLa Cells: Regulating HER1 Phosphorylation via Calmodulin/Calcineurin

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    In the human neoplastic cell lines 5637 and HeLa, recombinant CXCL12 elicited, as expected, downstream signals via both G-protein-dependent and β-arrestin-dependent pathways responsible for inducing a rapid and a late wave, respectively, of ERK1/2 phosphorylation. In contrast, the structural variant [N33A]CXCL12 triggered no β-arrestin-dependent phosphorylation of ERK1/2, and signaled via G protein-dependent pathways alone. Both CXCL12 and [N33A]CXCL12, however, generated signals that transinhibited HER1 phosphorylation via intracellular pathways. 1) Prestimulation of CXCR4/HER1-positive 5637 or HeLa cells with CXCL12 modified the HB-EGF-dependent activation of HER1 by delaying the peak phosphorylation of tyrosine 1068 or 1173. 2) Prestimulation with the synthetic variant [N33A]CXCL12, while preserving CXCR4-related chemotaxis and CXCR4 internalization, abolished HER1 phosphorylation. 3) In cells knockdown of β-arrestin 2, CXCL12 induced a full inhibition of HER1 like [N33A]CXCL12 in non-silenced cells. 4) HER1 phosphorylation was restored as usual by inhibiting PCK, calmodulin or calcineurin, whereas the inhibition of CaMKII had no discernable effect. We conclude that both recombinant CXCL12 and its structural variant [N33A]CXCL12 may transinhibit HER1 via G-proteins/calmodulin/calcineurin, but [N33A]CXCL12 does not activate β-arrestin-dependent ERK1/2 phosphorylation and retains a stronger inhibitory effect. Therefore, we demonstrated that CXCL12 may influence the magnitude and the persistence of signaling downstream of HER1 in turn involved in the proliferative potential of numerous epithelial cancer. In addition, we recognized that [N33A]CXCL12 activates preferentially G-protein-dependent pathways and is an inhibitor of HER1

    Evaluation of 18F-2-deoxy-2-fluoro-glucose positron emission tomography for gastric cancer screening in asymptomatic individuals undergoing endoscopy

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    18F-2-deoxy-2-fluoro-glucose Positron Emission Tomography (FDG-PET) has been recently proposed as a promising cancer-screening test. However, the validity of FDG-PET in cancer screening has not been evaluated. We investigated the sensitivity of FDG-PET compared with upper gastric endoscopy in gastric cancer screening for asymptomatic individuals. A total of 2861 consecutive subjects (1600 men and 1261 women) who were asymptomatic and who underwent both FDG-PET and upper gastrointestinal endoscopy between 1 February 2004 and 31 January 2005 were included in this study. Both endoscopists and a radiologist were unaware of the results of the other diagnostic tests. The FDG-PET images were examined using criteria determined by the pattern of FDG accumulation. Sensitivity and specificity of FDG-PET were calculated compared with endoscopic diagnosis as the gold standard. Among 2861 subjects enrolled in the study, there were 20 subjects with gastric cancer, of whom 18 were T1 in depth of cancer invasion. Positive FDG-PET results were obtained only in 2 of the 20 cancer subjects. The calculated sensitivity and specificity for overall gastric cancers were 10.0% (95% confidence interval (CI): 1.2–31.7%) and 99.2% (95% CI: 98.8–99.5%), respectively. 18F-2-deoxy-2-fluoro-glucose Positron Emission Tomography was poorly sensitive for detection of gastric cancer in the early stages

    Modelling Reveals Kinetic Advantages of Co-Transcriptional Splicing

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    Messenger RNA splicing is an essential and complex process for the removal of intron sequences. Whereas the composition of the splicing machinery is mostly known, the kinetics of splicing, the catalytic activity of splicing factors and the interdependency of transcription, splicing and mRNA 3′ end formation are less well understood. We propose a stochastic model of splicing kinetics that explains data obtained from high-resolution kinetic analyses of transcription, splicing and 3′ end formation during induction of an intron-containing reporter gene in budding yeast. Modelling reveals co-transcriptional splicing to be the most probable and most efficient splicing pathway for the reporter transcripts, due in part to a positive feedback mechanism for co-transcriptional second step splicing. Model comparison is used to assess the alternative representations of reactions. Modelling also indicates the functional coupling of transcription and splicing, because both the rate of initiation of transcription and the probability that step one of splicing occurs co-transcriptionally are reduced, when the second step of splicing is abolished in a mutant reporter
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