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de Azevedo M.B.,Brazilian Nuclear Energy Research Institute (IPEN)
International journal of nanomedicine | Year: 2011

Captopril (CAP) was the first angiotensin I-converting enzyme (ACE) inhibitor to be developed and is widely used in hypertension treatment. On the other hand, cyclodextrins (CDs) are cyclic oligosaccharides whose cone-shaped cavity allows formation of noncovalent inclusion complexes with appropriately sized guest molecules, thus modifying guest physical, chemical, and biological properties. Herein, the physicochemical characterization and in vivo ACE inhibition evaluation of seven CAP/CD complexes are reported. The inclusion complexes were prepared by spray-drying, freeze-drying, kneading, or lyophilization methods and characterized by nuclear magnetic resonance, Fourier-transformed infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, and scanning electron microscopy techniques. In vivo assays compared CAP and CAP/CD complex administration (0.5 mg kg(-1) or 0.09 mg kg(-1), n = 4-7) to evaluate the ACE inhibition by continuous infusion of angiotensin I (30 ng 50 μL(-1) min(-1)) in conscious Wistar rats. The physicochemical analysis demonstrated complete amorphization and complexation between CAP and CDs, indicating the substitution of water molecules inside the CD cavity with CAP. During the infusion of angiotensin I, the administration of all CAP/CD complexes induced a reduction in mean arterial pressure similar to that observed upon CAP administration. The nanoparticles obtained by the kneading method (CAP/α-CD:KM) showed a potent and long-lasting inhibitory activity (∼22 hours) on the angiotensin I pressor effect. The results suggest that the inclusion complex of CAP and α-CD can function as a novel antihypertensive formulation that may improve therapeutic use of CAP by reducing its oral dose administration to once per day, thus providing better quality of life for almost 25% of the world's population who suffer from hypertension.


Wetter N.U.,Brazilian Nuclear Energy Research Institute (IPEN) | Deana A.M.,Nove de Julho University
Laser Physics Letters | Year: 2013

We present a Nd:YLiF4 diode-side-pumped resonator architecture based on a gain-guided, mode-selective technique that employs a double pass of the fundamental laser mode through the crystal. The folded cavity is very compact, robust and cost efficient. With this design we demonstrate 19 W of quasi-cw, stable diffraction-limited laser emission at 1053 nm when pumping at 792 nm with 35.4 W. The slope efficiency of the laser is 65.3% and the optical-to-optical efficiency is 53.6%, which is, to the best of our knowledge, the highest efficiency reported for Nd:YLiF4 lasers pumped into the 4F5/2 band, including longitudinal pumping schemes and lasers emitting at the higher gain line of 1047 nm. © 2013 Astro Ltd.


Wetter N.U.,Brazilian Nuclear Energy Research Institute (IPEN) | Deana A.M.,Nove de Julho University
Applied Physics B: Lasers and Optics | Year: 2014

This work demonstrates the power scalability of double-beam-mode controlling, a technique that has generated the highest optical efficiency reported so far for Nd:YLF lasers. We analyze two types of power scaling possibilities by numerical simulations: multiplication of intracavity pump modules and MOPA configuration. About 44 W of TEM00 output power at 1053 nm was experimentally demonstrated with a beam-parameter product of 1.07 × 1.15. The results show great ease of power scaling without sacrificing beam quality. © 2014, Springer-Verlag Berlin Heidelberg.


Wetter N.U.,Brazilian Nuclear Energy Research Institute (IPEN) | Deana A.M.,Nove de Julho University
Optics Express | Year: 2015

We analyze the performance of a VBG equipped diode of narrow linewidth in a side-pumped double-beam, mode-controlled resonator and demonstrate power scaling without loss of beam quality by a factor of three, when compared to previous results. 69 W of diffraction-limited laser output power at 1053 nm in a Nd:YLF lasers are demonstrated with slope efficiency of 65% and record optical-to-optical efficiency of 60%. ©2015 Optical Society of America.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-IP-SICA | Phase: ENV.2011.4.1.1-1 | Award Amount: 8.67M | Year: 2011

Today, countries use a wide variety of methods to monitor the carbon cycle and it is difficult to compare data from country to country and to get a clear global picture. The current global observational and modelling capabilities allow us to produce estimates of carbon budget at different level (from local to global) but many uncertainties still remain. Decision makers need now more than ever systematic, consistent and transparent data, information and tools for an independent and reliable verification process of greenhouse gas emissions and sinks. Therefore higher quality and quantity of CO2 and CH4 data, from different domains and with an enhanced spatial and temporal resolution, need to be collected by a globally integrated observation and analysis system. This can be obtained by the coordinated Global Carbon Observation and Analysis System that this project aims at designing, addressing the climate targets of the Group on Earth Observations (GEO) toward building a Global Earth Observation System of Systems (GEOSS) for carbon. Specific objectives of the GEOCARBON project are: Provide an aggregated set of harmonized global carbon data information (integrating the land, ocean, atmosphere and human dimension) Develop improved Carbon Cycle Data Assimilation Systems (CCDAS) Define the specifications for an operational Global Carbon Observing System Provide improved regional carbon budgets of Amazon and Central Africa Provide comprehensive and synthetic information on the annual sources and sinks of CO2 for the globe and for large ocean and land regions Improve the assessment of global CH4 sources and sinks and develop the CH4 observing system component Provide an economic assessment of the value of an enhanced Global Carbon Observing System Strengthen the effectiveness of the European (and global) Carbon Community participation in the GEO system

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