1,203 research outputs found
Learning of Geological time in a sample of 9th grade Italian Liceo students
No full textGeological time is a pivotal concept in Earth sciences and many studies deal with it, but only few are interventional and none is known in Italy. We performed a study on the learning of geological time through a randomized controlled trial among 298 ninth grade liceo students of Friuli Venezia Giulia (Italy), including a pre-test, a short lecture, a post-test and a delayed test. Sample classes were randomly allocated to the experimental group (constructivist-style teaching) or to the control group (cognitivist-style teaching). Test scores displayed a significant improvement after the teaching and in the delayed test in both groups. Among students obtaining equal or better scores in the post-test, experimental group performed significantly better than control group. Science teachers of the same sample were also involved in the study. Few of them were familiar with misconceptions and taught geologic time, all showed a mix of post-cognitivist, cognitivist and behaviourist teaching approaches
Teaching Earth Sciences in Italian liceo high schools following the 2010 reform: a survey
No full textFollowing the recent upper secondary school reform (2010) in almost every Italian liceo high school there is a Natural Sciences curriculum (including Earth Sciences, Biology and Chemistry) spread over five years. The Ministry of Education issued guidelines without chronological separation between the three different subjects.
Given the novelty of the context, we decided to investigate how teachers are implementing the new Earth Sciences curriculum through the five teaching years by means of a survey. This has been administered as an anonymous on-line questionnaire between January and March 2014. The sample was chosen by randomisation from the population of science teachers working in Italian public liceo high school. Sample schools have been stratified according to geographical location and density of schools, 120 questionnaires from 76 schools (4.5% of the school population) have been collected.
The sample shows that the compliance with Ministry guidelines on the prescribed topics is highest in the 1st biennium, lower in the 2nd biennium (> 90% vs 72 -77% - according to the topics) and very low in the 5° year (73, 17 and 20% - according to the topics), in which teachers' choices appear heterogeneous.
The topics deemed indispensable by the sample were the ones already present in curricula before the reform.
Teaching organization seems affected by the limited weekly teaching time, and practical activities such as laboratory and fieldwork appear extremely reduced.
Regarding chosen textbooks, sample teachers generally indicate a few specific authors, while others are seldom chosen.
When asked about their knowledge of Earth Sciences, teachers expressed an overall positive self-perception, accompanied by interest for in-service training offer, preferably in mixed format (in attendance and on-line). This survey suggests that, due to the lack of guidance, the new curricula are being implemented autonomously by teachers, substantially grounding upon old curricula. The heterogeneous choices for the final year could be affected by uncertainty about the first post-reform state exam.
The study also indicates the need to start or enhance in-service teacher training. Novel strategies for implementing the new curricula are an opportunity to overcome old teaching practices largely based on a theoretical approach
Giulia Veronica Varisco
No full textThe headword explains the biography and the contribution of the author Giulia Varisco to the children's literatur
Radionuclide Delivery Strategies in Tumor Treatment: A Systematic Review
No full textThe aim of this review was to assess recent progress in targeted radionuclide tumor therapy, focusing on the best delivery strategies. A literature search was conducted in PubMed, Web of Science, and Scopus using the terms “radionuclides”, “liposomes”, “avidin–biotin interaction”, “theranostic”, and “molecular docking”. The 10 year filter was applied, except for the avidin–biotin interaction. Data were retrieved from both preclinical and clinical settings. Three targeting strategies were considered: pretargeting, liposomes, and ligands. Pretargeting can be achieved by exploiting the avidin–biotin interaction. This strategy seems very promising, although it has been investigated mainly in resectable tumors. Radiolabeled liposomes have attracted new interest as probes to identify the most suitable patients for treatment with liposomal formulations of common chemotherapeutics. The use of ligands for the delivery of radiotherapeutics to a specific target is still the most appealing strategy for treating tumors. The most appropriate ligand can be identified by virtually simulating its interaction with the receptor. All strategies showed great potential for use in targeted radionuclide therapy, but they also have numerous drawbacks. The most promising option is probably the one based on the use of new ligands
Head-to-Head Comparison between Peptide-Based Radiopharmaceutical for PET and SPECT in the Evaluation of Neuroendocrine Tumors: A Systematic Review
No full textWe compared head-to-head the most used radiolabeled peptides for single photon computed emission tomography (SPECT) and positron emission tomography (PET) imaging of neuroendocrine tumors (NETs). A comprehensive literature search was performed in PubMed, Web of Science, and Scopus databases. The following words, coupled two by two, were used: 68Ga-DOTATOC; 68Ga-DOTATATE; 68Ga-DOTANOC; 99mTc-EDDA/HYNIC-TOC; 64Cu-DOTATATE; and 111In-DTPA-octreotide. Moreover, a second-step search strategy was adopted by using the following combined terms: “Somatostatin receptor imaging,”; “Somatostatin receptor imaging” and “Functional,”; “Somatostatin receptor imaging” and “SPECT,”; and “Somatostatin receptor imaging” and “PET”. Eligible criteria were: (1) original articles focusing on the clinical application of the radiopharmaceutical agents in NETs; (2) original articles in the English language; (3) comparative studies (head-to-head comparative or matched-paired studies). Editorials, letters to the editor, reviews, pictorial essays, clinical cases, or opinions were excluded. A total of 1077 articles were found in the three electronic databases. The full texts of 104 articles were assessed for eligibility. Nineteen articles were finally included. Most articles focused on the comparison between 111In-DTPA-Octreotide and 68Ga-DOTATOC/TATE. Few papers compared 64Cu-DOTATATE and 68Ga-DOTATOC/TATE, or SPECT tracers. The rates of true positivity were 63.7%, 58.5%, 78.4% and 82.4%, respectively, for 111In-DTPA-Octreotide, 99mTc-EDDA/HYNIC-TOC, 68Ga-DOTATATE/TOC and 64Cu-DOTATATE. In conclusion, as highly expected, PET tracers are more suitable for the in vivo identification of NETs. Indeed, in comparative studies, they demonstrated a higher true positive rate than SPECT agents
Application of the integrated analytical approach to lipogels investigations by structure-surface correlations
No full textSTEAM GRANULATION VERSUS WET GRANULATION: IMPACT ON GRANULE AND TABLETS PROPERTIES
No full textSteam granulation (SG) involves the use of steam as the granulating medium instead of traditional liquid water [1]. Steam provides a higher diffusion rate into the powder bed and a more favourable thermal balance during the drying step. Due to the ability of the steam to diffuse, a reduction of up to 50% of the amount of water necessary for granulation is possible. Furthermore, the literature reports that the granules produced by SG have a larger surface area than those obtained with wet granulation (WG) [2]. However, no articles have been published on the effect of steam on the compressibility characteristics of the granules.
The purpose of this study was to compare the technological properties of granules and their relative tablets obtained with SG and WG. To evaluate the effect of the solubility and thickening power of the diluents on process performance, different formulations were used containing 20% (w/w) caffeine as a model drug, 50% (w/w) microcrystalline cellulose as granulating aid and 30% (w/w) diluent (maltodextrin, sorbitol, lactose or corn starch) were used. The preliminary rheological characterizations performed on the four formulations highlighted that SG requires a lower amount of liquid binder than conventional WG; moreover, SG generally allows better control of granule growth because it occurs more slowly than WG. Granulation experiments were performed using a standardized experimental procedure, and the granules, after drying in a ventilated oven, were characterized by sieve analysis to evaluate the particle size distribution and by measuring the tensile strength and uniformity of the content. A compression study was also performed to identify the compression mechanism. The granules obtained with SG are generally smaller, with a narrow particle size distribution and lower crushing strength. The granules were then compressed in a single punch tablet machine using different compression forces, and the tablets that had a tensile strength of 1-2 MPa were characterized by mass and content uniformity tests, disintegration and dissolution tests. The results demonstrate that the granules manufactured through SG have better compression properties and the tablets present shorter disintegration time and a faster caffeine release than those achieved through WG.
[1] S. Shanmugam, Granulation techniques and technologies: recent progress. BioImpacts (2015) 5 (1) 55-63.
[2] M. Vialpaldo, B. Albertini, N. Passerini, D. Bergers, P. Rombaut, J.A. Martens, G. Van Den Mooter, Agglomeration of mesoporous silica by melt and steam granulation. Part I: A comparison between disordered and ordered mesoporous silica. Journal of Pharmaceutical Sciences, 102 (2013) 3966-3977
STEAM GRANULATION VERSUS WET GRANULATION: IMPACT ON GRANULE AND TABLETS PROPERTIES
No full textSteam granulation (SG) involves the use of steam as the granulating medium instead of traditional liquid water [1]. Steam provides a higher diffusion rate into the powder bed and a more favourable thermal balance during the drying step. Due to the ability of the steam to diffuse, a reduction of up to 50% of the amount of water necessary for granulation is possible. Furthermore, the literature reports that the granules produced by SG have a larger surface area than those obtained with wet granulation (WG) [2]. However, no articles have been published on the effect of steam on the compressibility characteristics of the granules.
The purpose of this study was to compare the technological properties of granules and their relative tablets obtained with SG and WG. To evaluate the effect of the solubility and thickening power of the diluents on process performance, different formulations were used containing 20% (w/w) caffeine as a model drug, 50% (w/w) microcrystalline cellulose as granulating aid and 30% (w/w) diluent (maltodextrin, sorbitol, lactose or corn starch) were used. The preliminary rheological characterizations performed on the four formulations highlighted that SG requires a lower amount of liquid binder than conventional WG; moreover, SG generally allows better control of granule growth because it occurs more slowly than WG. Granulation experiments were performed using a standardized experimental procedure, and the granules, after drying in a ventilated oven, were characterized by sieve analysis to evaluate the particle size distribution and by measuring the tensile strength and uniformity of the content. A compression study was also performed to identify the compression mechanism. The granules obtained with SG are generally smaller, with a narrow particle size distribution and lower crushing strength. The granules were then compressed in a single punch tablet machine using different compression forces, and the tablets that had a tensile strength of 1-2 MPa were characterized by mass and content uniformity tests, disintegration and dissolution tests. The results demonstrate that the granules manufactured through SG have better compression properties and the tablets present shorter disintegration time and a faster caffeine release than those achieved through WG.
[1] S. Shanmugam, Granulation techniques and technologies: recent progress. BioImpacts (2015) 5 (1) 55-63.
[2] M. Vialpaldo, B. Albertini, N. Passerini, D. Bergers, P. Rombaut, J.A. Martens, G. Van Den Mooter, Agglomeration of mesoporous silica by melt and steam granulation. Part I: A comparison between disordered and ordered mesoporous silica. Journal of Pharmaceutical Sciences, 102 (2013) 3966-3977
Assessing Ocean Literacy in a sample of Italian primary and middle school students
No full textDespite the rise of Ocean Literacy (OL) movement at the beginning of 2000s, ocean sciences remain a neglected topic in school curricula of many countries, including Italy. This study investigates ocean-related knowledge and opinions in a sample of 351 primary and secondary school students of North Eastern Italy (4th, 5th and 8th grades) by means of structured questionnaires, before and after a teaching intervention aimed at promoting higher education and careers in the maritime sector. Students demonstrated a moderate level of knowledge and positive opinions about their relationship with the marine environment, as well as some misconceptions about the connectedness of all seas, the origin of half of atmospheric oxygen from the sea and the global dimension of water cycle. After the teaching intervention, primary school students’ scores evidenced a significant improvement, while secondary school results showed minimal change. This difference could possibly be attributed to differences in teaching organisation between primary and secondary schools. This is the first investigation on OL among Italian students, and is part of a larger project carried out by EMSEA (European Marine Science Educators Association) in three Mediterranean countries
Validation of orthopedic allograft preparation process: a new application of media fill test
No full text: Musculoskeletal allografts represent an important practice in orthopedic surgeries and the demand for them has been growing. For this reason, in order to reduce clinical risk and to more efficiently manage the increase of allograft usage and also to optimize timing of the surgeries, the thawing and washing processes with aseptic technique were centralized in the department of Hospital Pharmacy. This study describe the design and execution of an adapted Media Fill Test (MFT) to demonstrate aseptic thawing and washing of allografts. For this specific and innovative setting, to better simulate the actual processing steps, a surrogate system was developed to simulate the tendon allograft. The aseptic technique of four operators was assessed and an initial performance validation and the first revalidation were described. All MFT were completed successfully, with no observation of turbidity. The readapted MFT shown in this study can provide insight into this innovative and growing field to other health professionals who want to implement this service
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