147 research outputs found
Asociación de Difusión de Educación a Distancia A.D.E.D.
Conscious of the present needs, we enhance the idea of distance education.
First, as a project and then as an educational program, in order to train women and children, bearing family and society in mind.
A short and specific training that enables students retake abandoned studies was elaborated as the first step.
It has been proved that forming an Executive Assistant on a course of MERCOSUR Secretariat would become an efficient intermediate way to a program which will determine new conducts and promote to undertake higher studies.
Having achieved this experience as a distance education centre in the city of Mar del Plata.
The following characteristics and results have been evaluated:
* It is an ethical and social educational work.
* It is an educational offer that responds to regional requirements.* The learning-teaching material and tutelage are plurilingual and in accordance with the needs of the countries in which they will be implemented (Argentia, Bolivia, Brasil, Chile and Uruguay).
* It focuses on educational quality and makes use of technology, being adaptable to the students' different levels.
* With adequate financing, it has the capacity of continuous growth.
* It allows the creation of new distance educational centres in the region, enabling the intervening countries to both emit and receive the program.
* It teaches the characteristics and prospects of the common markets, considering their assets and liabilities.
* It complies with the principles of the last women's conference in China with the objectives of FIMU1, FLAMU2, UNESCO, OREALC, ADED3, meeting the needs of emerging countries. Besides, it expands educational frontier within the frame of globalization and interconnected present day world fostering job insertion4
Identification of a novel cord blood NK cell subpopulation expressing functional programmed death receptor-1
BackgroundNatural Killer cells (NKs) represent the innate counterpart of TCRαβ lymphocytes and are characterized by a high anti-tumor and an anti-viral cytotoxic activity. Recently, it has been demonstrated that NKs can express PD-1 as an additional inhibitory receptor. Specifically, PD-1 was identified on a subpopulation of terminally differentiated NKs from healthy adults with previous HCMV infection. So far it is unknown whether PD-1 appears during NK-cell development and whether this process is directly or indirectly related to HCMV infection.MethodsIn this study, we analyzed the expression and function of PD-1 on Cord Blood derived NKs (CB-NKs) on a large cohort of newborns through multiparametric cytofluorimetric analysis.ResultsWe identified PD-1 on CB-NKs in more than of half the newborns analyzed. PD-1 was present on CD56dim NKs, and particularly abundant on CD56neg NKs, but only rarely present on CD56bright NKs. Importantly, unlike in adult healthy donors, in CB-NKs PD-1 is co-expressed not only with KIR, but also with NKG2A. PD-1 expression was independent of HCMV mother seropositivity and occurs in the absence of HCMV infection/reactivation during pregnancy. Notably, PD-1 expressed on CB-NKs was functional and mediated negative signals when triggered.ConclusionTo our understanding, this study is the first to report PD-1 expression on CB derived NKs and its features in perinatal conditions. These data may prove important in selecting the most suitable CB derived NK cell population for the development of different immunotherapeutic treatments
Micro-morphologic changes around biophysically-stimulated titanium implants in ovariectomized rats
<p>Abstract</p> <p>Background</p> <p>Osteoporosis may present a risk factor in achievement of osseointegration because of its impact on bone remodeling properties of skeletal phsiology. The purpose of this study was to evaluate micro-morphological changes in bone around titanium implants exposed to mechanical and electrical-energy in osteoporotic rats.</p> <p>Methods</p> <p>Fifteen 12-week old sprague-dowley rats were ovariectomized to develop osteoporosis. After 8 weeks of healing period, two titanium implants were bilaterally placed in the proximal metaphyses of tibia. The animals were randomly divided into a control group and biophysically-stimulated two test groups with five animals in each group. In the first test group, a pulsed electromagnetic field (PEMF) stimulation was administrated at a 0.2 mT 4 h/day, whereas the second group received low-magnitude high-frequency mechanical vibration (MECHVIB) at 50 Hz 14 min/day. Following completion of two week treatment period, all animals were sacrificed. Bone sites including implants were sectioned, removed <it>en bloc </it>and analyzed using a microCT unit. Relative bone volume and bone micro-structural parameters were evaluated for 144 μm wide peri-implant volume of interest (VOI).</p> <p>Results</p> <p>Mean relative bone volume in the peri-implant VOI around implants PEMF and MECHVIB was significantly higher than of those in control (<it>P </it>< .05). Differences in trabecular-thickness and -separation around implants in all groups were similar (<it>P </it>> .05) while the difference in trabecular-number among test and control groups was significant in all VOIs (<it>P </it>< .05).</p> <p>Conclusion</p> <p>Biophysical stimulation remarkably enhances bone volume around titanium implants placed in osteoporotic rats. Low-magnitude high-frequency MECHVIB is more effective than PEMF on bone healing in terms of relative bone volume.</p
Peri-implant bone damage procured by piezoelectric and conventional implant site preparation: An in vitro comparison
Background: The conventional drill technique is the most commonly used for the implant site preparation of the desired diameter and length. Ultrasonic implant site preparation (UISP) can also be used to perform an implant site preparation of the desired dimensions. Methods: Implant sites were prepared in fresh bone ribs with two different implant site preparation techniques: implant surgical drills and piezoelectric tips. Samples were analyzed with scanning electron microscopy (SEM) for evaluating the peri-implant bone damage. Result: In the surgical drills group, the cortical bone surface showed several cracks and the bone vascular canals were hidden by a dense smear layer. Cancellous bone showed large irregularities and trabecular fractures. The piezoelectric group showed a clean and smooth cortical bone surface with opened bone vascular canals; the cancellous bone presented a regular morphology, and the trabecular spaces, clearly visible, were free of debris. Conclusions: Ultrasonic implant site preparation showed cleaner bone surfaces and lower bone trauma compared with the preparation using implant surgical drills
Peri-Implant Bone Damage Procured by Piezoelectric and Conventional Implant Site Preparation:An In Vitro Comparison
The conventional drill technique is the most commonly used for the implant
site preparation of the desired diameter and length. Ultrasonic implant site preparation (UISP) can also
be used to perform an implant site preparation of the desired dimensions. Methods: Implant sites were
prepared in fresh bone ribs with two di\ufb00erent implant site preparation techniques: implant surgical
drills and piezoelectric tips. Samples were analyzed with scanning electron microscopy (SEM) for
evaluating the peri-implant bone damage. Result: In the surgical drills group, the cortical bone surface
showed several cracks and the bone vascular canals were hidden by a dense smear layer. Cancellous
bone showed large irregularities and trabecular fractures. The piezoelectric group showed a clean
and smooth cortical bone surface with opened bone vascular canals; the cancellous bone presented
a regular morphology, and the trabecular spaces, clearly visible, were free of debris. Conclusions:
Ultrasonic implant site preparation showed cleaner bone surfaces and lower bone trauma compared
with the preparation using implant surgical drills
Lithium-Ion Energy Storage Systems in Smart Grid Applications: Modeling and Analysis
Nowadays, modern smart grids require the implementation of Energy Storage Systems (ESS) in order to optimize the production, consumption and distribution of electrical energy. In particular, ESS add a degree of freedom to the system which allows to cover the mismatch between production and demand while providing other grid support services. Lithium Ion Batteries have proven to be mature to serve in several applications involving different stakeholders. In fact, their characteristics in terms of aging, specific power and response times are superior to other energy storage technologies.
The aim of the thesis is to develop and study a model which simulates a Lithium-Ion based storage system operating in some selected applications. The model is built in the MATLAB and Simulink environment, and it considers several aspects: electrical connections, thermal behavior, aging prediction, controlling and economic performance. Overall, the comprehensive model is developed thanks to large amounts of experimental data which make it accurate and flexible. Great relevance is given to the aging model which is designed starting from experimental results and fatigue algorithms: both calendar and cycle aging are considered.
Three relevant energy storage system applications are selected and studied: RES-BESS, energy arbitrage and island grid. In all cases a simulation of one year is performed employing the developed model after an accurate design procedure. The operating conditions of the storage system are checked and analyzed throughout the simulation. Aging is the main index to be evaluated to asses the sustainability of the application. Finally, depending on the specific application, revenue sources are identified and calculated.
With current prices of Lithium Ion batteries, all applications resulted to be hardly economically sustainable. However, considering the decreasing trend of prices, these applications may be very interesting in the medium and long term (about a decade) confirming the relevance of the research
The Roncesvalles ambush
Resumen: El 25 de agosto de 778 fue diezmada la retaguardia del ejército carolingio, cuando se disponía a pasar los Pirineos para volver a su tierra. La emboscada habría sido consumada por los vascos de Pamplona y de otros valles cercanos, para castigar el desmantelamiento de Pamplona por los francos, que la dejaban indefensa frente al hostigamiento continuo de los moros. La tradición rolandiana española revela el extraordinario poder de la poesía, que durante la Edad Media logró elevar los espíritus, por encima de toda discordia política entre hispanos y francosAbstract: On August 25 778 one tenth of the Carolingian rear guard was killed as it started to cross the Pyrenees on its way back home . The ambush had been preparad by the Basques from Pamplon a and the nearest valleys, in order to punish the Francs' attack of Pamplona, thus left unprotecte d from the continuous harassment of the Moors . The Spanish tradition of Roland reveals the extraordinary power of poetry, which throughout the Middle Ages managed to elevate the spirits , aboye any political dispute between Hispanics and Francs
- …