507 research outputs found
Pedagogía digital y pandemia: Características, aciertos y obstáculos de la enseñanza de la química en nivel superior
Tesis de Maestría en Educación en Ciencias Experimentales y Tecnología, Facultad de Ciencias Exactas, Físicas y Naturales de la Universidad Nacional de Córdoba. Año 2023.Fil: Basso, Ana Valentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Durante la pandemia por COVID-19 debieron realizarse adecuaciones a la enseñanza en todos los niveles. Debido al Aislamiento Social Preventivo y Obligatorio, se adaptó la educación presencial a una educación a distancia, que estuvo basada principalmente en las nuevas tecnologías de red. Esta política pública requirió que docentes implementen modificaciones en las dimensiones pedagógicas, comunicacionales y tecnológicas de manera imprevista y obligada. Sumado a ese contexto de emergencia, la incertidumbre acerca de la accesibilidad y al desconocimiento del nivel de alfabetización tecnológica, incrementaron las dificultades al momento de la implementación. El objetivo principal de esta tesis es describir y caracterizar las estrategias de enseñanza en entornos virtuales y su relación con la Pedagogía Digital en asignaturas de Química pertenecientes a carreras de las ciencias naturales de la Universidad Nacional de Córdoba durante el contexto de pandemia. A los fines de este trabajo, para conocer el nivel de Competencia Digital Docente, se realizó una encuesta a través de Google forms a una población de 132 docentes de nivel superior. Para recopilar experiencias se entrevistaron en profundidad a nueve docentes universitarios a través de videollamadas por Google meet. La principal conclusión es que las características y estrategias que se implementaron en el nivel superior no pertenecieron a los postulados de la Educación a Distancia Digital sino que se corresponden a una nueva categoría denominada Educación Remota de Emergencia. Además, las decisiones pedagógicas implementadas en espacios de enseñanza virtual no se correspondieron con la pedagogía digital y por lo tanto podrían haber obstaculizado el aprendizaje de conceptos químicos. Las principales razones fueron lo emergente de la situación y el bajo nivel de competencias digitales que presentaron los y las docentes, quienes con todas las limitaciones y dificultades señaladas, hicieron lo mejor que pudieron en un contexto de incertidumbre y altamente estresante.Fil: Basso, Ana Valentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina
Phytochemical study of the Genus Salpichroa (Solanaceae), chemotaxonomic considerations, and biological evaluation in prostate and breast cancer cells
Twelve Salpichroa taxa have been phytochemically analyzed. From the aerial parts of S. scandens, four known salpichrolides A, C, I, S, and an unreported withanolide named salpichrolide V (1), were isolated. In S. dependens, S. gayi, S. glandulosa subsp. glandulosa, S. glandulosa subps. weddellii, S. leucantha, S. micrantha, S. microloba, S. proboscidea, S. ramosissima, S. tristis var. tristis, and S. weberbauerii, no withanolides were found. The chemical content of ca. 85% of the Salpichroa taxa is in agreement with molecular studies, which suggest that Salpichroa and Jaborosa, a genus considered morphologically close to Salpichroa, are distant in the systematic of the Solanoideae subfamily. Moreover, the in vitro cytotoxic activity of a set of natural salpichrolides and derivatives was examined against two prostate carcinoma cell lines (PC3 and LNCaP) and two human breast cancer cell lines (MCF-7 and T47D). Several compounds showed moderate activity (IC50 = 64.91 – 29.97 μm).Fil: Basso, Ana Valentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Leiva González, Segundo. Universidad Privada Atenor Orrego; PerúFil: Barboza, Gloria Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Careaga Quiroga, Valeria Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Calvo, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Sacca, Paula Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Nicotra, Viviana Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin
Implementation, performance and physics impact of particle identification at Higgs factories
This work introduces the software tool Comprehensive Particle Identification
(CPID). It is a modular approach to combined PID for future Higgs factories and
implemented in the Key4hep framework. Its structure is explained, the current
module library laid out and initial performance measures for the ILD detector
as an example presented. A basic run of CPID works already as well as the
default full-simulation ILD PID reconstruction, but allows for an easy and
convenient addition of more PID observables, improving PID performance in
future analyses and high-level reconstruction, such as strange tagging.Comment: Poster presented at: The European Physical Society Conference on High
Energy Physics (EPS-HEP2023), 21-25 August 2023, Hamburg, German
Acid rain in context: a didactic proposal with STS approach
Se presenta el diseño de una propuesta didáctica sobre la problemática de la lluvia ácida desde un enfoque CTS, para la asignatura químicageneral en la carrera de formación de profesores de biología. La propuestaconsta de una secuencia de cinco actividades interdisciplinares que incluyen laexplicitación de ideas previas, el análisis de textos, el trabajo con diferentes sistemas representacionales (gráficos, fórmulas químicas, imágenes satelitales) ypráctica experimental. Se espera que esta propuesta favorezca a la apropiacióndel conocimiento científico y el compromiso socioambiental.The design of a didactic proposal on the problem of acid rain is presented from a STS approach, for the general chemical subject in the training course of biology professors. The proposal consists of a sequence of five interdisciplinary activities that include the explicitation of previous ideas, the analysis of texts, work with different representational systems (graphics, chemical formulas, satellite images) and experimental practice. It is expected that this proposal will favor the appropriation of scientific knowledge and socio-environmental commitment.Fil: Basso, Ana Valentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; ArgentinaFil: Lorenzo, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Centro de Investigación y Apoyo a la Educación Científica; Argentin
Defective Mitochondrial Pyruvate Flux Affects Cell Bioenergetics in Alzheimer's Disease-Related Models
Summary: Mitochondria are key organelles for brain health. Mitochondrial alterations have been reported in several neurodegenerative disorders, including Alzheimer's disease (AD), and the comprehension of the underlying mechanisms appears crucial to understand their relationship with the pathology. Using multiple genetic, pharmacological, imaging, and biochemical approaches, we demonstrate that, in different familial AD cell models, mitochondrial ATP synthesis is affected. The defect depends on reduced mitochondrial pyruvate oxidation, due to both lower Ca2+-mediated stimulation of the Krebs cycle and dampened mitochondrial pyruvate uptake. Importantly, this latter event is linked to glycogen-synthase-kinase-3β (GSK-3β) hyper-activation, leading, in turn, to impaired recruitment of hexokinase 1 (HK1) to mitochondria, destabilization of mitochondrial-pyruvate-carrier (MPC) complexes, and decreased MPC2 protein levels. Remarkably, pharmacological GSK-3β inhibition in AD cells rescues MPC2 expression and improves mitochondrial ATP synthesis and respiration. The defective mitochondrial bioenergetics influences glutamate-induced neuronal excitotoxicity, thus representing a possible target for future therapeutic interventions. : Mitochondria are key organelles for brain health. Rossi et al. show that, in different Alzheimer's disease cell models, lower mitochondrial Ca2+ signal and pyruvate uptake reduce ATP synthesis. GSK-3β hyper-activation contributes to the defect by impairing HK1-mitochondria association, decreasing MPC2 levels and destabilizing MPC complexes. Defective bioenergetics affects neuronal functionality. Keywords: Alzheimer's disease, presenilin, mitochondrial metabolism, bioenergetics, calcium homeostasis, pyruvate, mitochondrial pyruvate carrier, hexokinase 1, GSK-3
IVF outcome is optimized when embryos are replaced between 5 and 15 mm from the fundal endometrial surface: a prospective analysis on 1184 IVF cycles
BACKGROUND: Some data suggest that the results of human in vitro fertilization (IVF) may be affected by the site of the uterine cavity where embryos are released. It is not yet clear if there is an optimal range of embryo-fundus distance (EFD) within which embryos should be transferred to optimize IVF outcome. METHODS: The present study included 1184 patients undergoing a blind, clinical-touch ET of 1–2 fresh embryos loaded in a soft catheter with a low amount of culture medium. We measured the EFD using transvaginal US performed immediately after ET, with the aim to assess (a) if EFD affects pregnancy and implantation rates, and (b) if an optimal EFD range can be identified. RESULTS: Despite comparable patients’ clinical characteristics, embryo morphological quality, and endometrial thickness, an EFD between 5 and 15 mm allowed to obtain significantly higher pregnancy and implantation rates than an EFD above 15 mm. The abortion rate was much higher (although not significantly) when EFD was below 5 mm than when it was between 5 and 15 mm. Combined together, these results produced an overall higher ongoing pregnancy rate in the group of patients whose embryos were released between 5 and 15 mm from the fundal endometrial surface. CONCLUSIONS: The site at which embryos are released affects IVF outcome and an optimal EFD range exists; this observations suggest that US-guided ET could be advantageous vs. clinical-touch ET, as it allows to be more accurate in releasing embryos within the optimal EFD range
Quality of Life and psychopathology in adults who underwent Hematopoietic Stem Cell Transplantation (HSCT) in childhood: a qualitative and quantitative analysis.
Background: Patients who undergo pediatric Hematopoietic Stem Cell Transplantation (HSCT) may experience long-term psychological sequelae and poor Quality of Life (QoL) in adulthood. This study aimed to investigate subjective illness experience, QoL, and psychopathology in young adults who have survived pediatric HSCT.
Method: The study involved patients treated with HSCT in the Hematology-Oncology Department between 1984 and 2007. Psychopathology and QoL were investigated using the SCL-90-R and SF-36. Socio-demographic and medical information was also collected. Finally, participants were asked to write a brief composition about their experiences of illness and care. Qualitative analysis of the texts was performed using T-LAB, an instrument for text analysis that allows the user to highlight the occurrences and co-occurrences of lemma. Quantitative analyses were performed using non-parametric tests (Spearman correlations, Kruskal-Wallis and Mann-Whitney tests).
Results: Twenty-one patients (9 males) participated in the study. No significant distress was found on the SCL-90 Global Severity Index, but it was found on specific scales. On the SF-36, lower scores were reported on scales referring to bodily pain, general health, and physical and social functioning. All the measures were significantly (p < 0.05) associated with specific socio-demographic and medical variables (gender, type of pathology, type of HSCT, time elapsed between communication of the need to transplant and effective transplantation, and days of hospitalization). With regard to the narrative analyses, males focused on expressions related to the body and medical therapies, while females focused on people they met during treatment, family members, and donors. Low general health and treatment with autologous HSCT were associated with memories about chemotherapy, radiotherapy, and the body parts involved, while high general health was associated with expressions focused on gratitude (V-Test \ub1 1.96).
Conclusion: Pediatric HSCT survivors are more likely to experience psychological distress and low QoL in adulthood compared with the general population. These aspects, along with survivors' subjective illness experience, show differences according to specific medical and socio-demographic variables. Studies are needed in order to improve the care and long-term follow-up of these families
QUATERNARY BUILD-UPS AND RHODALGAL CARBONATES ALONG THE ADRIATIC AND IONIAN COASTS OF THE ITALIAN PENINSULA: A REVIEW
In the Mediterranean, build-ups (created by coralline algae, Cladocora caespitosa, deep-water corals, vermetids, polychaetes and bacteria) and rhodolith beds are important hot-spots of biodiversity. Being severely threatened by anthropogenic impact and climate change, they have been included in international directives on environmental protection. This work wants to support the ongoing research on modern bioconstructions by providing further data on the long-term effects of environmental factors on these habitats. Our results are based on the analysis of the existing literature on the outcropping Quaternary successions of the Adriatic and Ionian coasts of peninsular Italy. The existing reports of build-ups and rhodalgal carbonates have been summarized in an homogeneous data-set and then studied to highlight distribution patterns in space and time. The analyses consistently outlined the importance of sedimentation rate in controlling the general distribution of build-ups and rhodalgal carbonates. The majority of the reports is concentrated south of the Gargano, where the sediment-load of the rivers is small. The majority of the reports is related to coralline algae, suggesting that they were the main carbonate producers during the period. C. caespitosa general distribution is mainly controlled by temperature, with most of the occurrences dating back to the warm periods of the late Ionian and of the Tarantian. Large build-ups of Cladocora are restricted to embayments and gulfs well-protected against storm waves. The distribution of the outcrops of deep-water corals is biased by the geological setting. A remarkable uplift is necessary to bring these corals from their original deep-water setting to elevated areas onshore. Consequently, most of the outcrops are in Southern Calabria which is characterized by a strong Quaternary uplift. Chemosynthetic build-ups, intertidal bioconstructions (made by vermetids, polychaetes or coralline algae), as well as stromatolites, are rare in the study area
Hepatoblastoma and microRNA-483 two forms and one outcome
Hepatoblastoma (HB) is the most common liver cancer in infants younger than 3 years. Its onset has been associated with other genetic syndromes and some genetic and biochemical markers has been identified recently in this neoplasia. Nevertheless the patients have a poor prognosis and the resection or transplantation remains the only effective therapeutic approach. The identification of non-invasive markers may represent an innovative approach and may contribute to a more accurate histological classification of this tumor. We previously demonstrated that some microRNAs are helpful in discriminating HB from hepatocellular carcinoma. In this study, we describe the involvement of the two forms of microRNA-483 (-3p and -5p) in a selected cohort of HB patients who underwent surgical resection or liver transplantation. Differently from other liver diseases we observed that the quantitative expression of the two forms did not significantly changed among patients. Furthermore, 3p/5p ratio was different between HB and non-HB samples, being positive in the latter and negative in HB samples. Influence of concomitant treatments in the expression of miR-483 (i.e. chemotherapy, and immunosuppressive drugs) was also evaluated and no changes were found in the follow-up. In conclusion the expression and function of miR-483-3p/5p in HB still remains unclear and further studies are needed to elucidate the possible mechanisms that regulate the different strand selection between the two forms of microRNA-483 in patients affected by HB. We deem that the analysis of microRNA-483 different forms could be useful for the molecular identification of HB patients and the discrimination with non-HB patient
Role of Extracellular Vesicles in Amyotrophic Lateral Sclerosis
Amyotrophic Lateral Sclerosis (ALS) is the most common motor neuron disease in adults and primarily targets upper and lower motor neurons. The progression of the disease is mostly mediated by altered intercellular communication in the spinal cord between neurons and glial cells. One of the possible ways by which intercellular communication occurs is through extracellular vesicles (EVs) that are responsible for the horizontal transfer of proteins and RNAs to recipient cells. EVs are nanoparticles released by the plasma membrane and this review will describe all evidence connecting ALS, intercellular miscommunication and EVs. We mainly focus on mutant proteins causing ALS and their accumulation in EVs, along with the propensity of mutant proteins to misfold and propagate through EVs in prion-like behavior. EVs are a promising source of biomarkers and the state of the art in ALS will be discussed along with the gaps and challenges still present in this blooming field of investigation
- …