190 research outputs found

    the modernity of the meraner lehrplan for teaching geometry today in grades 10 11 exploiting the power of dynamic geometry systems

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    In 1905, at the meeting of the Deutschen Mathematiker-Vereinigung in Meran, the "Meraner Lehrplan," a mathematics syllabus, was proposed. This document, which contains many of Felix Klein's ideas on teaching geometry in school, proposed approaching geometry via intuitive geometry, which is the ability to see in space, in order to provide elements for both interpreting the real world and developing logical skills (see Treutlein in Der geometrische anschauungsunterricht als unterstufe eines zweistufigen geometrischen unterrichtes an unseren hoheren schulen. Teubner, Leipzig/Berlin 1911). Klein's ideas still hold today: An intuitive approach to geometry can be facilitated using information technology. Some activities related to a space geometry approach based on the analogy among figures and on the use of a dynamic geometry system will be presented in this chapter

    Buccal mucosa is a promising graft in Peyronie's disease surgery. Our experience and a brief literature review on autologous grafting materials

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    AIM: Peyronie's Disease (PD) is an under reported acquired benign condition that, at the moment, is not curable with medical therapy. Surgery represent the gold standard of treatment. Surgical approaches are several and they consist in "plication techniques" or plaque incision/excision with grafting of resulting albuginea defect. Among grafting procedures, albuginea defect substitution with autologous materials demonstrated over the years not inferior results respect to heterologous grafts. Buccal mucosa graft (BMG) is not usually emphasized in many review articles and clinical series are yet limited. METHODS: We present our experience with seventeen plaque incision procedures and BMG in surgical correction of complex penile curvatures due to PD performed in a period of 30 months. Our analyses was focused on buccal mucosa graft characteristics as major determinant of the surgical success. We also conducted a brief literature review on autologous grafting materials used in reconstructive penile surgery for PD. RESULTS: Our cosmetics and functional results consists in a 100% of functional penile straightening with no relapses and 5,8% of de novo erectile dysfunction. Mean age was 56.4 years, mean follow-up of 22.5 (6-36) months. No complications graft related were observed. Operative time was 115.3 minutes in mean. Over 94% of patients referred they were "really much better" and "much better" satisfied based on PGI-I questionnaire administrated at the last follow- up visit. CONCLUSION: BMG is revealing as an optimal choice for reconstructive surgery in PD. Anatomical characteristics consisting in the great elasticity, the quick integration time and the easy harvesting technique lead to high cosmetics and functional success rate, without omitting economical and invasiveness aspects

    La Lingua Matematica: un'esperienza didattica nel Liceo Matematico

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    In questo lavoro si presenta un modulo didattico dal titolo La Lingua Matematica, rivolto a studenti del primo anno di scuola secondaria di secondo grado.Il modulo è stato presentato in classi di Liceo Matematico, ma può essere proposto anche in altri contesti. Esso ha un duplice obiettivo: introdurre questioni relative a matematica e linguaggio da un lato e introdurre i concetti di teorema e dimostrazione dall'altro. Il percorso ha permesso di introdurre nozioni di aritmetica modulare e ha condotto gli studenti a confrontarsi, elaborare ipotesi, produrre argomentazioni e generare nuovi teoremi

    N-Acetylcysteine causes analgesia in a mouse model of painful diabetic neuropathy

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    N-Acetylcysteine, one of the most prescribed antioxidant drugs, enhances pain threshold in rodents and humans by activating mGlu2 metabotropic glutamate receptors. Here, we assessed the analgesic activity of N-acetylcysteine in the streptozotocin model of painful diabetic neuropathy and examined the effect of N-acetylcysteine on proteins that are involved in mechanisms of nociceptive sensitization. Mice with blood glucose levels ≥250 mg/dl in response to a single intraperitoneal (i.p.) injection of streptozotocin (200 mg/kg) were used for the assessment of mechanical pain thresholds. Systemic treatment with N-acetylcysteine (100 mg/kg, i.p., either single injection or daily injections for seven days) caused analgesia in diabetic mice. N-acetylcysteine-induced analgesia was abrogated by the Sxc- inhibitors, sulfasalazine (8 mg/kg, i.p.), erastin (30 mg/kg, i.p.), and sorafenib (10 mg/kg, i.p.), or by the mGlu2/3 receptor antagonist, LY341495 (1 mg/kg, i.p.). Repeated administrations of N-acetylcysteine in diabetic mice reduced ERK1/2 phosphorylation in the dorsal region of the lumbar spinal cord. The analgesic activity of N-acetylcysteine was occluded by the MEK inhibitor, PD0325901 (25 mg/kg, i.p.), the TRPV1 channel blocker, capsazepine (40 mg/kg, i.p.), or by a cocktail of NMDA and mGlu5 metabotropic glutamate receptor antagonists (memantine, 25 mg/kg, plus MTEP, 5 mg/kg, both i.p.). These findings offer the first demonstration that N-acetylcysteine relieves pain associated with diabetic neuropathy and holds promise for the use of N-acetylcysteine as an add-on drug in diabetic patients

    Implementación de codificación diagnostica basado en SNOMED-CT Swiss Medical Group Argentina

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    La codificación de diagnósticos se viene desarrollando hace varios años para las causas de muertes, enfermedades y actos clínicos, en seguimiento por la Organización Mundial de la Salud, usándose el CIE 10, Clasificación Internacional de Enfermedades Versión 10. Siendo necesario para fines tanto estadísticos o científicos tener un adecuado sistema de codificación, para poder fácilmente interpretar e identificar diferentes situaciones y acciones médicas, sin necesidad de recurrir al texto libre.Sociedad Argentina de Informática e Investigación Operativ

    Implementación de codificación diagnostica basado en SNOMED-CT Swiss Medical Group Argentina

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    La codificación de diagnósticos se viene desarrollando hace varios años para las causas de muertes, enfermedades y actos clínicos, en seguimiento por la Organización Mundial de la Salud, usándose el CIE 10, Clasificación Internacional de Enfermedades Versión 10. Siendo necesario para fines tanto estadísticos o científicos tener un adecuado sistema de codificación, para poder fácilmente interpretar e identificar diferentes situaciones y acciones médicas, sin necesidad de recurrir al texto libre.Sociedad Argentina de Informática e Investigación Operativ

    Implementación de codificación diagnostica basado en SNOMED-CT Swiss Medical Group Argentina

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    La codificación de diagnósticos se viene desarrollando hace varios años para las causas de muertes, enfermedades y actos clínicos, en seguimiento por la Organización Mundial de la Salud, usándose el CIE 10, Clasificación Internacional de Enfermedades Versión 10. Siendo necesario para fines tanto estadísticos o científicos tener un adecuado sistema de codificación, para poder fácilmente interpretar e identificar diferentes situaciones y acciones médicas, sin necesidad de recurrir al texto libre.Sociedad Argentina de Informática e Investigación Operativ

    Multiband optical variability of 3C 279 on diverse time-scales

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    We have monitored the flat spectrum radio quasar, 3C 279, in the optical B, V, R, and I passbands from 2018 February to 2018 July for 24 nights, with a total of 716 frames, to study flux, colour, and spectral variability on diverse time-scales. 3C 279 was observed using seven different telescopes: two in India, two in Argentina, two in Bulgaria, and one in Turkey to understand the nature of the source in optical regime. The source was found to be active during the whole monitoring period and displayed significant flux variations in B, V, R, and I passbands. Variability amplitudes on intraday basis varied from 5.20 to 17.9 per cent. A close inspection of variability patterns during our observation cycle reveals simultaneity among optical emissions from all passbands. During the complete monitoring period, progressive increase in the amplitude of variability with frequency was detected for our target. The amplitudes of variability in B, V, R, and I passbands have been estimated to be 177 per cent, 172 per cent, 171 per cent, and 158 per cent, respectively. Using the structure function technique, we found intraday time-scales ranging from ∼23 min to about 115 min. We also studied colour–magnitude relationship and found indications of mild bluer-when-brighter trend on shorter time-scales. Spectral indices ranged from 2.3 to 3.0 with no clear trend on long-term basis. We have also generated spectral energy distributions for 3C 279 in optical B, V, R, and I passbands for 17 nights. Finally, possible emission mechanisms causing variability in blazars are discussed briefly.Fil: Agarwal, Aditi. Indian Institute of Astrophysics; IndiaFil: Cellone, Sergio Aldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Complejo Astronómico "El Leoncito". Universidad Nacional de Córdoba. Complejo Astronómico "El Leoncito". Universidad Nacional de la Plata. Complejo Astronómico "El Leoncito". Universidad Nacional de San Juan. Complejo Astronómico "El Leoncito"; ArgentinaFil: Andruchow, Ileana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Mammana, Luis Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Complejo Astronómico "El Leoncito". Universidad Nacional de Córdoba. Complejo Astronómico "El Leoncito". Universidad Nacional de la Plata. Complejo Astronómico "El Leoncito". Universidad Nacional de San Juan. Complejo Astronómico "El Leoncito"; ArgentinaFil: Singh, Mridweeka. Aryabhatta Research Institute of Observational Sciences; IndiaFil: Anupama, G. C.. Indian Institute of Astrophysics; IndiaFil: Mihov, B.. Bulgarian Academy of Sciences; BulgariaFil: Raj, Ashish. Indian Institute of Astrophysics; IndiaFil: Slavcheva Mihova, L.. Bulgarian Academy of Sciences; BulgariaFil: Özdönmez, Aykut. Tübİtak National Observatory; TurquíaFil: Ege, Ergün. Istanbul University; Turquí

    Diagnostic value of plasma p-tau181, NfL, and GFAP in a clinical setting cohort of prevalent neurodegenerative dementias

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    Background: Increasing evidence supports the use of plasma biomarkers of neurodegeneration and neuroinflammation to screen and diagnose patients with dementia. However, confirmatory studies are required to demonstrate their usefulness in the clinical setting. Methods: We evaluated plasma and cerebrospinal fluid (CSF) samples from consecutive patients with frontotemporal dementia (FTD) (n = 59), progressive supranuclear palsy (PSP) (n = 31), corticobasal syndrome (CBS) (n = 29), dementia with Lewy bodies (DLB) (n = 49), Alzheimer disease (AD) (n = 97), and suspected non-AD physiopathology (n = 51), as well as plasma samples from 60 healthy controls (HC). We measured neurofilament light chain (NfL), phospho-tau181 (p-tau181), and glial fibrillary acid protein (GFAP) using Simoa (all plasma biomarkers and CSF GFAP), CLEIA (CSF p-tau181), and ELISA (CSF NfL) assays. Additionally, we stratified patients according to the A/T/N classification scheme and the CSF α-synuclein real-time quaking-induced conversion assay (RT-QuIC) results. Results: We found good correlations between CSF and plasma biomarkers for NfL (rho = 0.668, p < 0.001) and p-tau181 (rho = 0.619, p < 0.001). Plasma NfL was significantly higher in disease groups than in HC and showed a greater increase in FTD than in AD [44.9 (28.1–68.6) vs. 21.9 (17.0–27.9) pg/ml, p < 0.001]. Conversely, plasma p-tau181 and GFAP levels were significantly higher in AD than in FTD [3.2 (2.4–4.3) vs. 1.1 (0.7–1.6) pg/ml, p < 0.001; 404.7 (279.7–503.0) vs. 198.2 (143.9–316.8) pg/ml, p < 0.001]. GFAP also allowed discriminating disease groups from HC. In the distinction between FTD and AD, plasma p-tau181 showed better accuracy (AUC 0.964) than NfL (AUC 0.791) and GFAP (AUC 0.818). In DLB and CBS, CSF amyloid positive (A+) subjects had higher plasma p-tau181 and GFAP levels than A− individuals. CSF RT-QuIC showed positive α-synuclein seeding activity in 96% DLB and 15% AD patients with no differences in plasma biomarker levels in those stratified by RT-QuIC result. Conclusions: In a single-center clinical cohort, we confirm the high diagnostic value of plasma p-tau181 for distinguishing FTD from AD and plasma NfL for discriminating degenerative dementias from HC. Plasma GFAP alone differentiates AD from FTD and neurodegenerative dementias from HC but with lower accuracy than p-tau181 and NfL. In CBS and DLB, plasma p-tau181 and GFAP levels are significantly influenced by beta-amyloid pathology

    Multi-band behaviour of the TeV blazar PG 1553+113 in optical range on diverse timescales. Flux and spectral variations

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    Context. The TeV BL Lac object PG1553+113 is one of the primary candidates for a binary supermassive black hole system.Aims. We study the flux and spectral variability of PG1553+113 on intra-night to long-term timescales using (i) BVRI data collected over 76 nights from January 2016 to August 2019 involving nine optical telescopes and (ii) historical VR data (including ours) obtained for the period from 2005 to 2019.Methods. We analysed the light curves using various statistical tests, fitting and cross-correlation techniques, and methods for the search for periodicity. We examined the colour-magnitude diagrams before and after the corresponding light curves were corrected for the long-term variations.Results. Our intra-night monitoring, supplemented with literature data, result in a low duty cycle of ∼(10?18)%. In April 2019, we recorded a flare, which marks the brightest state of PG1553+113 for the period from 2005 to 2019: R ≃ 13.2mag. This flare is found to show a clockwise spectral hysteresis loop on its VR colour-magnitude diagram and a time lag in the sense that the V-band variations lead the R-band ones.We obtain estimates of the radius, the magnetic field strength, and the electron energy that characterize the emission region related to the flare.We find a median period of (2.21±0.04) years using the historical light curves. In addition, we detect a secondary period of about 210 days using the historical light curves corrected for the long-term variations. We briefly discuss the possible origin of this period.Fil: Agarwal, A.. Indian Institute Of Astrophysics; India. Raman Research Institute; IndiaFil: Mihov, B.. Institute Of Astronomy And Nao; BulgariaFil: Andruchow, Ileana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Cellone, Sergio Aldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Complejo Astronómico "El Leoncito". Universidad Nacional de Córdoba. Complejo Astronómico "El Leoncito". Universidad Nacional de la Plata. Complejo Astronómico "El Leoncito". Universidad Nacional de San Juan. Complejo Astronómico "El Leoncito"; ArgentinaFil: Anupama, G. C.. Indian Institute Of Astrophysics; IndiaFil: Agrawal, V.. Embibe; IndiaFil: Zola, S.. Jagiellonian University; PoloniaFil: Slavcheva Mihova, L.. Institute Of Astronomy And Nao; BulgariaFil: Özdönmez, A.. Ataturk University; TurquíaFil: Ege, E.. Istanbul University; TurquíaFil: Raj, A.. University Enclave; IndiaFil: Mammana, Luis Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Complejo Astronómico "El Leoncito". Universidad Nacional de Córdoba. Complejo Astronómico "El Leoncito". Universidad Nacional de la Plata. Complejo Astronómico "El Leoncito". Universidad Nacional de San Juan. Complejo Astronómico "El Leoncito"; ArgentinaFil: Zibecchi, Lorena Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Fernandez Lajus, Eduardo Eusebio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentin
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