385 research outputs found
La innovación como proceso: aplicación a la enseñanza de temas introductórios de Termodinámica
El presente trabajo muestra algunos resultados de un primer análisis de las actividades incluidas en una propuesta innovadora sobre temas de Termodinámica. Esta propuesta contempló aspectos conceptuales y metodológicos de temas básicos comprendidos en un curso introductorio. La propuesta incluyó modificaciones no sólo en la presentación de los conceptos sino también en la actividad desarrollada en clase por los alumnos y en la ejercitación posterior.
Estuvo enmarcada en un proceso que involucró a dos cátedras de distintos niveles de una misma Facultad y se caracterizó por una realimentación entre la implementación de los cambios y la evaluación del aprendizaje logrado. El análisis de una evaluación sistemática de la incorporación de conceptos, tale como energía, trabajo y calor, mostró, junto a una mejor incorporación y persistencia en el tiempo de los conceptos indagados, la necesidad de un cuidadoso diseño de los instrumentos de evaluación.Some of the results obtained through the analysis of activities included in an innovative proposal on the teaching of thermodynamics at an introductory level are shown. This proposal dealt with conceptual and methodological aspects about basic concepts and included changes in the way these concepts were introduced and in-classroom student activities. The innovative process, involving two courses of different level which belong to the same School, was characterized by a constant feedback between implementation of changes and evaluation of student achievement. The systematic assessment done through testing of concepts such as energy, work and heat has shown not only a better incorporation and permanence of the inquired concepts but also suggests the need of careful survey design.Fil: Bordogna, C.. Universidad Nacional de la Plata. Facultad de Ingeniería. Departamento de Fisicomatemática; ArgentinaFil: Cotignola, M. I.. Universidad Nacional de la Plata. Facultad de Ingeniería. Departamento de Fisicomatemática; ArgentinaFil: Punte, Graciela Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Capannini, O. M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física de Líquidos y Sistemas Biológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física de Líquidos y Sistemas Biológicos; Argentin
Bayesian Updating Rules in Continuous Opinion Dynamics Models
In this article, I investigate the use of Bayesian updating rules applied to
modeling social agents in the case of continuos opinions models. Given another
agent statement about the continuous value of a variable , we will see that
interesting dynamics emerge when an agent assigns a likelihood to that value
that is a mixture of a Gaussian and a Uniform distribution. This represents the
idea the other agent might have no idea about what he is talking about. The
effect of updating only the first moments of the distribution will be studied.
and we will see that this generates results similar to those of the Bounded
Confidence models. By also updating the second moment, several different
opinions always survive in the long run. However, depending on the probability
of error and initial uncertainty, those opinions might be clustered around a
central value.Comment: 14 pages, 5 figures, presented at SigmaPhi200
A multi-layered Bayesian network model for structured document retrieval
New standards in document representation, like for example SGML, XML, and MPEG-7, compel Information Retrieval to design and implement models and tools to index, retrieve and present documents according to the given document structure. The paper presents the design of an Information Retrieval system for multimedia structured documents, like for example journal articles, e-books, and MPEG-7 videos. The system is based on Bayesian Networks, since this class of mathematical models enable to represent and quantify the relations between the structural components of the document. Some preliminary results on the system implementation are also presented
Ranking structured documents using utility theory in the Bayesian network retrieval model
In this paper a new method based on Utility and Decision theory is presented to deal with structured documents. The aim of the application of these methodologies is to refine a first ranking of structural units, generated by means of an Information Retrieval Model based on Bayesian Networks. Units are newly arranged in the new ranking by combining their posterior probabilities, obtained in the first stage, with the expected utility of retrieving them. The experimental work has been developed using the Shakespeare structured collection and the results show an improvement of the effectiveness of this new approach
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Integrating and normalising coaching as a routine practice in doctoral supervision
Aim/Purpose: Recent research highlights the growing decline in doctoral students’ mental health and wellbeing, caused not only by the pressures, stress, and isolation of doctoral studies but also by existential issues around personal development and future prospects. Consequently, we argue that there is an urgent need to reassess the supervisory process to support doctoral students in addressing these concerns. This paper offers a potential solution to this challenge by exploring and examining how integrating coaching methods into doctoral supervision can support doctoral students’ growth and development, thereby increasing their wellbeing and human flourishing. Coaching aims to help individuals produce optimal performance and improvements in personal and professional settings by deploying a series of tools and models. Coaching is essentially a non-directive form of development, enabling people to identify goals and skills and then extracting the capacity people have within themselves to achieve their ambitions. This paper explores how coaching methods could be made a regular feature of doctoral supervision.
Background: The need to reconfigure doctoral supervision as a practice to address humanistic issues regarding whole-person development, self-actualisation, and personal worth is nothing new. Over the years, researchers have produced models of doctoral supervision, highlighting the growing need for supervision to incorporate more pastoral and emancipatory elements, which facilitate personal growth instead of focusing purely on academic function and criticality. Although coaching is identified in previous studies as being a valuable addition, nothing examines how to modify existing supervision practices to accommodate more pastoral elements.
Methodology: This paper offers a conceptual analysis whereby the argument primarily synthesizes existing research on doctoral supervision to understand why coaching methods may provide a solution to the evolving requirements of student welfare and emancipation. Since the commentary in this paper is not based on the findings of an empirical study, the following two conceptual research questions frame the discussion. First, are coaching methods beneficial when super-vising doctoral students? Second, what are the challenges when implementing and integrating coaching methods into existing doctoral supervisory practice? The paper utilises the Normalisation Process Theory as a ‘thinking tool’ to help answer these questions. The theory evaluates phenomena in applied social research settings to help understand how complex practices are made workable and integrated into context-dependent ways. Therefore, the theory acts as an analytical tool, enabling researchers to think through implementation issues when designing complex interventions and their evaluation.
Contribution: This paper contributes to knowledge by highlighting ways in which management responsible for a doctoral provision in higher education settings can modify their organisational structures and systems to encourage coaching methods to become a normalised part of doctoral supervision, thereby legitimising its practice.
Findings: The Normalisation Process Theory has value because it produces a roadmap for integrating and implementing new or modified practices into existing systems of operation. It, therefore, assists by producing an output that enables a current/new practice to be dissected and categorised under specific headings. In this research context, this output assisted in understanding the operational challenges when considering the normalisation of a practice. The theory helped generate something managers tasked with managing doctoral provision could consider (i.e., institutional paradigms, policies, regulations, etc.) when thinking about what may need to be reconfigured to enable coaching methods to become an integrated and normalised part of doctoral supervision over time.
Recommendations for Practitioners: It is recommended that practitioners consider the integration of coaching methods into supervision. First, once implemented, it requires monitoring to ensure the practice’s quality and consistency amongst the supervisory community. Secondly, to assess the impact of the practice on other services within the organisation, such as student services or faith services, and thirdly, to ensure training in coaching methods is made timely and relevant to assist all academics involved in doctoral supervision.
Recommendations for Researchers: The authors recommend collecting empirical evidence using the Normalisation Process Theory to evaluate the integration and normalisation of a range of practices in higher education settings. Moreover, once implemented, more research is required on the long-term value of coaching methods within doctoral settings.
Impact on Society: Doctoral education is increasingly significant in a world where knowledge is fundamental to generating economic growth. Identified as having the technical and professional skills needed to fuel the knowledge-based economy, student wellbeing, and mental health must be optimal to ensure they can contribute to the knowledge-based economy as effectively as possible.
Future Research: More research must be conducted on how doctoral supervision can become more humanistic; for example, by focusing on student self-awareness, reflection, and reframing instead of just the traditional academic function. Consequently, improving these facets is vital in developing sustained wellbeing and life-long success
2q37 deletions in patients with an albright hereditary osteodystrophy phenotype and PTH resistance
Pseudohypoparathyroidism (PHP) is a rare endocrine disorder derived from the defective activation of the cAMP pathway by the parathyroid hormone secondary to GNAS molecular defects. PHP subtypes are defined by the presence/absence of specific clinical/biochemical features. PHP1A is characterized by resistance to multiple hormones with features of Albright hereditary osteodystrophy (AHO), while pseudopseudohypoparathyroidism (PPHP) is characterized by AHO in the absence of PTH resistance. Small subsets of PHP and PPHP patients without known molecular defects have been re-diagnosed as being affected by the brachydactyly-mental retardation syndrome (BDMR), also known as the AHO-like syndrome. This study aimed to analyse 24 PHP1A and 51 PPHP patients without a molecular diagnosis for the presence of BDMR-associated 2q37 deletions to improve the differential diagnosis and to identify features that might help to avoid a misdiagnosis. Molecular investigations identified 4 deletions in 4 unrelated patients. The affected patients showed a combination of the most pathognomonic AHO features. Of note, 3 of the patients also displayed mild PTH resistance, and none of the patients developed ectopic ossifications. Our work confirmed the rarity of the misdiagnosis of BDMR in PHP patients through the identification of 4 patients bearing a 2q37 deletion in a cohort of 73 PHP patients (5.3%). Three patients with the deletion presented a PHP1A phenotype in the absence of any BDMR-specific findings. Further studies on larger case series are needed to elucidate the overlap between these clinical entities and to allow the early identification of patients
Improved Molecular Diagnosis of McCune-Albright Syndrome and Bone Fibrous Dysplasia by Digital PCR
McCune-Albright syndrome (MAS) is a rare congenital disorder characterized by the association of endocrine and nonendocrine anomalies caused by somatic activating variants of GNAS. The mosaic state of variants makes the clinical presentation extremely heterogeneous depending on involved tissues. Biological samples bearing a low level of mosaicism frequently lead to false-negative results with an underestimation of causative molecular alterations, and the analysis of biopsies is often needed to obtain a molecular diagnosis. To date, no reliable analytical method for the noninvasive testing of blood is available. This study was aimed at validating a novel and highly sensitive technique, the digital PCR (dPCR), to increase the detection rate of GNAS alterations in patients with a clinical suspicion of MAS and, in particular, in blood. We screened different tissues (blood, bone, cutis, ovary, and ovarian cyst) collected from 54 MAS patients by different technical approaches. Considering blood, Sanger was unable to detect mutations, the allele-specific PCR and the co-amplification at lower denaturation temperature had a 9.1% and 18.1% detection rate, respectively, whereas the dPCR reached a 37.8% detection rate. In conclusion, the dPCR resulted in a cost-effective, reliable, and rapid method allowing the selective amplification of low-frequency variants and able to improve GNAS mutant allele detection, especially in the blood
Concordance Between Tissue ALK Detection by Immunohistochemistry and Plasma ALK Detection by Next-Generation Sequencing in the Randomized Phase 3 ALEX Study in Patients With Treatment-Naive Advanced ALK-Positive NSCLC
INTRODUCTION: The Blood First Assay Screening Trial revealed the clinical applicability of blood-based next-generation sequencing to identify patients with ALK-positive NSCLC for alectinib treatment. To understand the relationship between tissue-based versus blood-based testing, we retrospectively investigated concordance between VENTANA ALK (D5F3) CDx immunohistochemistry and the FoundationACT (FACT; Foundation Medicine, Inc.) plasma assay, and compared clinical efficacy between phase 3 ALEX study subpopulations.
METHODS: Patients with advanced ALK-positive (by immunohistochemistry) NSCLC were randomized 1:1 to alectinib 600 mg or crizotinib 250 mg, twice daily. Assessable baseline plasma samples were analyzed for ALK positivity by FACT; positive percent agreement with immunohistochemistry was evaluated. Progression-free survival (PFS), duration of response, and objective response rate were compared between intention-to-treat (ITT) and biomarker-evaluable populations, and plasma ALK-positive and plasma ALK-negative subpopulations.
RESULTS: In the ITT population (303 patients; alectinib, 152; crizotinib, 151), all patients had ALK-positive tumors by immunohistochemistry. In the biomarker-evaluable population (149 patients; alectinib, 76; crizotinib, 73), 105 had plasma ALK-positive and 44 had plasma ALK-negative tumors. Positive percent agreement between immunohistochemistry and FACT was 70.5% (105 of 149; 95% confidence interval: 62.5-77.7). Baseline characteristics were generally balanced, with some exceptions, notably tumor burden. Median PFS in plasma ALK-positive and ALK-negative patients was 22.4 months and not estimable with alectinib and 7.3 months and 12.9 months with crizotinib, respectively; median duration of response was 25.9 months and not estimable with alectinib and 5.6 months and 11.5 months with crizotinib, respectively.
CONCLUSIONS: Reasonable concordance between FACT and immunohistochemistry was observed; both methods are valuable in identifying ALK-positive patients, separately or concurrently. Alectinib was found to have superior PFS in the plasma ALK-positive population, as in the ITT population
Reorganización e integración curricular en un curso universitario inicial de Física
The influence of different educational approaches on the acquisition of scientific concepts, procedures and attitudes in a basic course on physics for engineering students gave rise to a proposal involving curricular and methodological innovations in mechanics and thermodynamics. Its aim was to focusteaching on fundamental laws and highlight the importance of methodological tools in Physics. The analysis of the introduced changes led to a process characterized by the ongoing assessment of the strategies in progress and the linking of curricular changes to the fulfillment of specially designed tasksto be developed in class. In these tasks students had an active role in building up their knowledge.</p
Mosaicism for GNAS methylation defects associated with pseudohypoparathyroidism type 1B arose in early post-zygotic phases
BACKGROUND:
Pseudohypoparathyroidism type 1B (PHP1B; MIM#603233) is a rare imprinting disorder (ID), associated with the GNAS locus, characterized by parathyroid hormone (PTH) resistance in the absence of other endocrine or physical abnormalities. Sporadic PHP1B cases, with no known underlying primary genetic lesions, could represent true stochastic errors in early embryonic maintenance of methylation. Previous data confirmed the existence of different degrees of methylation defects associated with PHP1B and suggested the presence of mosaicism, a phenomenon already described in the context of other IDs.
RESULTS:
With respect to mosaic conditions, the study of multiple tissues is a necessary approach; thus, we investigated somatic cell lines (peripheral blood and buccal epithelium and cells from the urine sediment) descending from different germ layers from 19 PHP patients (11 spor-PHP1B, 4 GNAS mutated PHP1A, and 4 PHP with no GNAS (epi)genetic defects) and 5 healthy controls. We identified 11 patients with epigenetic defects, further subdivided in groups with complete or partial methylation defects. The recurrence of specific patterns of partial methylation defects limited to specific CpGs was confirmed by checking methylation profiles of spor-PHP1B patients diagnosed in our lab (n\u2009=\u200956). Underlying primary genetic defects, such as uniparental disomy or deletion, potentially causative for the detected partial methylation were excluded in all samples.
CONCLUSIONS:
Our data showed no differences of methylation levels between organs and tissues from the same patient, so we concluded that the epimutation occurred in early post-zygotic phases and that the partial defects were mosaics. The number of patients with no detectable (epi)genetic GNAS defects was too small to exclude epimutations occurring in later post-zygotic phases, affecting only selected tissues different from blood, thus leading to underdiagnosis during routine molecular diagnosis. Finally, we found no correlation between methylation ratios, representing the proportion of epimutated cells, and the clinical presentation, further confirming the hypothesis of a threshold effect of the GNAS loss of imprinting leading to an "all-or-none" phenotype
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