1,721,015 research outputs found
Polymer films comprising material secreted by gastropods
No full textThe present invention refers to a film, comprising at least one polymer and a material
secreted by a gastropod, in particular snail slime. The present invention also relates to a
5 procedure for the preparation and to uses of such film, in particular medical and cosmetic
uses, including veterinary uses. Further objects of the present invention include kits, films
for the storage and/or packaging of food, patches, masks and similar cosmetic products
comprising such film
FILM POLIMERICI COMPRENDENTI MATERIALE SECRETO DA GASTEROPODI
No full textLa presente invenzione si riferisce ad una pellicola o film, comprendente un polimero ed un materiale secreto da un gasteropode, in particolare bava di lumaca. La presente invenzione riguarda inoltre il procedimento di preparazione e gli usi, in particolare gli usi medici e gli usi cosmetici, anche veterinari, di tale composizione. Sono altresì oggetto della presente invenzione kit, pellicole per la conservazione e/o il confezionamento di cibi, cerotti, maschere e prodotti cosmetici simili comprendenti tale composizione
MAKING LEARNING AND THINKING VISIBLE. AN ANALYSIS ON THE USE OF THINKING ROUTINES
No full textThis paper describes the first phase of the research project titled MLTV - Making Learning and Thinking
Visible in Italian Secondary Schools, stemmed from a collaboration between INDIRE, the National
Institute for Documentation, Innovation and Educational Research and Project Zero (PZ), a research
group of the Harvard Graduate School of Education. The project started in 2017 and it is still ongoing.
Phase I covers the school year 2017-18, when three upper secondary schools (in the Northern, Central
and Southern Italy) experimented in their classrooms the MLV (Making Learning Visible) and the VT
(Visible Thinking) frameworks of PZ. The core themes of the MLTV project are the following ones: 1.
group learning - defined as a collection of persons who are emotionally, intellectually, and aesthetically
engaged in solving problems, creating products, and making meaning in which each person learns
autonomously and through the ways of learning of others; 2. documentation - defined as “the practice
of observing, recording, interpreting, and sharing through different media the processes and products
of learning in order to deepen learning” [1, p.74]; 3. and Thinking Routines (TRs) - defined as structured
tools used over and over again in the classroom, that support specific thinking moves (i.e. making
connections, describing what’s there, building explanations, considering different viewpoints and
perspectives etc.). The project draws on previous research on thinking and learning skills, and, in
particular, is based on the following conceptual basis: thinking is not only a matter of skill; it is
dispositional, distributed, and can be made visible through particular routines and practices. Learning
does not happen in loneliness but it is distributed, hence it is socially constructed among individuals,
groups, and cultural tools and artifacts [1]. Learning is seen as a consequence of thinking [2]: it is
purposeful, emotional, social, and representational [1]. It takes place throughout all our lives.
Understanding is performative, or it is real when applicable in new situations [3]. This contribution,
focusing on Phase I, tries to represent and analyse the employment of Thinking Routines in all the
classes that were included in the experimentation, in order to look at what types of thinking and thinking
skills teachers were more interested in and therefore tried to develop in their students. Each school
participated with a different number of classes of different age levels, with a total number of 15 classes
and about 300 students, which is the outreach of the first year. The project is still in place, at present
facing Phase 2, whose main purpose is disseminating its promising initial results to other upper
secondary schools in Italy (25 schools). In Phase 3, Indire plans to scale-up, through a cascade model,
to other schools, potentially all interested ones, of lower levels too
Montmorillonite Reinforced Type A Gelatin Nanocomposites.
No full textThis study investigates the structural, morphological, thermal, and mechanical properties of type A gelatin/montmorillonite (MMT) films as a function of MMT concentration. The variations of the X-ray diffraction pattern suggest that the structure of the nanocomposites turns from intercalated to exfoliated on increasing clay loading up to 20 wt %. Simultaneously, gelatin interaction
with clay negative sheets during gelling provokes a reduction of the triple helix content of the composite films, in Agreement with the reduction of the relative intensity of the 1.1 nm diffraction reflection of gelatin and of the values of denaturation enthalpy.
On the other hand, the increase of the denaturation and decomposition temperatures, the significant rise of the Young’s modulus, as well as the swelling decrease observed as clay content increases, demonstrate a relevant stabilizing effect of MMT on gelatin. The reinforcement
action of MMT allows to utilize a relatively low concentration of the crosslinking agent genipin to further stabilize the films. The synergic action of clay and genipin prevents dissolution of the nanocomposites in aqueous solution and enhances their mechanical properties
Multi-composite system for the delivery of alendronate to bone tissue
No full textBakground
The bisphosphonate (BPs) class drug, is widely employed for the treatment of a variety of bone disorders. In this work Sodium
Alendronate (AL) was utilised as model Bisphosphonate drug. AL is often administered orally or via injection showing many side
effects. Recently different release approaches have been evaluated in order to targeted AL delivery to bone. In particular calcium
phosphate cements (CPCs) have been investigated as potential carries of BPs [1, 2]. The CPCs are bioactive and biodegradable
grafting materials made of powders of suitable composition which, when mixed with a liquid phase, give a modulable paste which
stiffens during the setting reaction and sets as primarily calcium-deficient hydroxyapatite. Unfortunately, the loading of AL interferes
with the conversion of pristine powders (like alfa-tricalcium phosphate, alfa-TCP) into hydroxyapatite, increasing the setting times
and worsening the mechanical properties. Therefore, the amount of AL that can be directly loaded is limited (1.8 mg / g) [1, 2].
Consequently, the drug encapsulation might overcome this drawback.
The aim of this work was to develop an innovative drug delivery system potentially useful for the delivery of AL to bone tissue. In
particular, we propose the use of Solid Lipid Microparticles (MPs), up to now mainly used for oral and topical drug delivery, as
carrier for AL, due to the favourable biocompatibility and lower toxicity of the lipids compared with many polymers. Thus a multicomposite
delivery platform consisted of a biomimetic-tricalcium phosphategelatin cement (CPCs) enriched with alendronate-loaded
MPs (MPs-AL) was developed.
Main results
For the preparation of the MPs, the spray congealing technology was employed [3]. In particular six different excipient were
considered: Stearic acid, Stearyl alcohol, Cutina® HR, Precirol® ATO 5 and Tristearin. In order to screen the effect of types,
dimensions and amount of unloaded MPs on the CPCs most important mechanical properties a Design of Experiment (DoE) was
employed. Then, MPs loaded with 10 % w/w of AL were produced using the different carriers. All MPs-AL exhibited a spherical
shape, encapsulation efficiency higher than 90% and prevalent particle size ranging from 100-150 micron. Solid state
characterization by means of DSC, HSM and X-ray powder diffraction demonstrated that encapsulation of the drug into MPs did not
alter its crystal structure. MPs-AL addition to the cement provoked a modest lengthening of the setting times and of the hardening
reaction leading to the complete transformation of alfa-TCP into calcium-deficient hydroxyapatite, without significantly affect the
cement mechanical properties. Then MPs loaded with different concentration of AL (10%, 20% and 30%) were embedded into the
CPC. The in vitro AL release studies from the multi-composite system (carried out in PB buffers at pH 7.4 at 37°C) showed that all
the system allowed a controlled release of the drug over time.
Therefore the results of this study demonstrated that it was possible to increase the amount of AL into the CPCs up to 10 time
compared to the value previously reported [1,2]. Moreover, the use of MPs as carriers to enrich bone cement formulation with AL
was a successful strategy to develop a system for the controlled local delivery of the drug.
Future and prospective
To value the effect of the AL release from CPCs-MPs system on cellular proliferation and differentiation, in vitro studies using
osteoblasts and osteoclasts cell cultures are in progress.
The obtain results suggest that this designed composite system could be useful for the delivery of other drugs (i.e. antibiotic, antiinflammatory
agents and anticancer drugs) to bone tissue
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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