460 research outputs found
Novedades terapéuticas en el tratamiento del asma
International audienc
A convex-programming-based guidance algorithm to capture a tumbling object on orbit using a spacecraft equipped with a robotic manipulator
An algorithm to guide the capture of a tumbling resident space object by a spacecraft equipped with a robotic manipulator is presented. A solution to the guidance problem is found by solving a collection of convex programming problems. As convex programming offers deterministic convergence properties, this algorithm is suitable for onboard implementation and real-time use. A set of hardware-in-the-loop experiments substantiates this claim. To cast the guidance problem as a collection of convex programming problems, the capture maneuver is divided into two simultaneously occurring sub-maneuvers: a system-wide translation and an internal re-configuration. These two sub-maneuvers are optimized in two consecutive steps. A sequential convex programming procedure, overcoming the presence of non-convex constraints and nonlinear dynamics, is used on both optimization steps. A proof of convergence is offered for the system-wide translation, while a set of structured heuristics—trust regions—is used for the optimization of the internal re-configuration sub-maneuver. Videos of the numerically simulated and experimentally demonstrated maneuvers are included as supplementary material
A tip-tilt hardware-in-the-loop air-bearing test bed with physical emulation of the relative orbital dynamics
29th AAS/AIAA Space Flight Mechanics Meeting: Ka’anapali, Maui, Hawaii, U.S.A. Volume: Advances in the Astronautical Sciences (Vol. 168, pp. 3781–3799). Univelt Inc.A new hardware-in-the-loop (HIL) air bearing testbed that is capable of physically emulating the relative orbital dynamics is presented. Typically, air bearing testbeds consist of test vehicles operating on top of a planar and horizontally-leveled sur face. These test vehicles use air bearings to reduce the friction with the operating surface to negligible levels. The low friction, combined with the horizontally leveled surface, creates a low residual acceleration environment. These dynamics are representative of the environment that spacecraft experience during close proximity maneuvers. To extend the applicability of planar air bearing test beds to longer maneuvers or separations relative orbital dynamics need to be emulated. In this paper, using Hill-Clohessy-Wilshire dynamics, we emulated the relative orbital dynamics of a real spacecraft using a scaled Floating Spacecraft Simulator (FSS) on a dynamically inclined operating surface. The mathematical constructs of the tilt angles, screw height displacements and scaling parameters are developed via Euler’s rotation theorem, Buckingham’s Pi theorem and the similarity principle. The applicability of the new idea is demonstrated via a circumnavigation maneuver scenario of a spacecraft in a Low Earth Orbit (LEO). The simulation results show the viability and suitability of the new approach
Zimosis en vinos
We have isolated one sporulate yeast strain that produce a thick pellicle on the top of a disease
wine.
lt has been made the taxonomyc study in pure culture and it was analysed it's probable systematic
position. It has been reproduced the disease in a lot of wines.
The analitie results revea that the alcohol is kept without harmfull but the total accidity is
considerably reduced by the yeast effect.Se aĂsla una levadura esporulada que forma gruesa pelĂcula en la superficie de
un vino alterado.
Se hace el estudio taxonĂłmico en cultivo puro.
Se analiza su probable ubicación sistemática. Se reproduce la formación de
pelĂcula en una serie de vinos del comercio. Los datos analĂticos revelan que el
alcohol no es oxidado, pero sĂ la acciĂłn zimĂłgeno modifica la proporciĂłn de
ácidos totales que se reducen apreciablemente.
Para mayores detalles sobre los métodos empleados nos remitirnos a nuestros
trabajos citados en la bibliografĂa con los n% 4 y 5.Fil: De Pritz, MarĂa J. R..
Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Llop, Armando A.
Uso de los antihistamĂnicos en patologĂa alĂ©rgica
AntihistamĂnic; Al·lèrgia; UrticĂ ria; Rinitis; Efectes adversos; InteraccionsAntihistamĂnico; Alergia; Urticaria; Rinitis; Efectos adversos; InteraccionesAntihistamine; Allergy; Urticaria; Rhinitis; Adverse effects; InteractionsEls antihistamĂnics anti-H1 sĂłn els fĂ rmacs mĂ©s emprats per al tractament de les malalties al·lèrgiques. Es classifiquen
en antihistamĂnics de primera generaciĂł (clorfeniramina, difenhidramina, hidroxizina) i de segona
generaciĂł (bilastina, cetirizina, desloratadina, ebastina, fexofenadina, levocetirizina, loratadina, rupatadina).
Actualment, per via oral, es recomana utilitzar sempre antihistamĂnics de segona generaciĂł amb una acciĂł
més selectiva sobre els receptors H1 i una baixa liposolubilitat que permet una distribució limitada al sistema
nerviĂłs central (SNC). En cas de necessitar un antihistamĂnic parenteral nomĂ©s es disposa de la dexclorfeniramina,
que Ă©s de primera generaciĂł.
Els antihistamĂnics sĂłn efectius en el tractament de les rinoconjuntivitis al·lèrgiques i les urticĂ ries de qualsevol
etiologia. L’elevada prevalença de la rinitis en la poblaciĂł general (20%) fa que la prescripciĂł d’antihistamĂnics
sigui molt elevada. En la rinitis són més efectius per tractar la mucositat, la pruïja i els esternuts que la congestió
nasal. TambĂ© s’utilitzen com a tractament de la urticĂ ria crònica espontĂ nia. AixĂ mateix, els antihistamĂnics no
controlen la pruĂŻja de la dermatitis atòpica ni sĂłn el tractament de primera lĂnia en l’anafilaxi.
Els antihistamĂnics anti-H1 sĂłn, en general, fĂ rmacs ben tolerats. Els de primera generaciĂł creuen la barrera
hematoencefà lica i poden produir sedació i efectes anticolinèrgics centrals (confusió, agitació, etc.) i perifèrics
(retenciĂł d’orina, sequedat de boca, xerostomia). En el cas que un pacient necessiti tractament antihistamĂnic
és important tenir en compte la cà rrega anticolinèrgica dels fà rmacs que està prenent; això resulta especialment
rellevant en pacients d’edat avançada.
Un altre efecte advers d’alguns antihistamĂnics, potencialment greu, Ă©s la prolongaciĂł de l’interval QT, que va
motivar la retirada del mercat de fĂ rmacs com astemizole i terfenadina.
Cal tenir present que hi ha certs grups de població (embarassades, lactants, edat avançada, insuficiència renal
i/o hepĂ tica i nens i nenes) en els quals els antihistamĂnics s’han de prescriure amb precauciĂł tenint en compte
les recomanacions de la fitxa tècnica del fà rmac.
En aquest ButlletĂ es revisen els antihistamĂnics disponibles per a les principals malalties al·lèrgiques al nostre
entorn.Los antihistamĂnicos antiH1 son los fármacos más utilizados para el tratamiento de las enfermedades alĂ©rgicas.
Se clasifican en antihistamĂnicos de primera generaciĂłn (clorfeniramina, difenhidramina, hidroxicina) y de
segunda generaciĂłn (bilastina, cetirizina, desloratadina, ebastina, fexofenadina, levocetirizina, loratadina, rupatadina).
Actualmente, por vĂa oral, se recomienda utilizar siempre antihistamĂnicos de segunda generaciĂłn
con una acción más selectiva sobre los receptores H1 y una baja liposolubilidad que permite una distribución
limitada en el sistema nervioso central (SNC). En caso de precisar un antihistamĂnico parenteral solo se dispone
de la dexclorfeniramina, que es de primera generaciĂłn.
Los antihistamĂnicos son efectivos en el tratamiento de las rinoconjuntivitis alĂ©rgicas y las urticarias de cualquier
etiologĂa. La elevada prevalencia de la rinitis en la poblaciĂłn general (20%) hace que la prescripciĂłn de
antihistamĂnicos sea muy elevada. En la rinitis son más efectivos para tratar la mucosidad, el prurito y los estornudos
de la congestión nasal. También se utilizan como tratamiento de la urticaria crónica espontánea. Aun
asĂ, los antihistamĂnicos no controlan el prurito de la dermatitis atĂłpica ni son el tratamiento de primera lĂnea
en la anafilaxis.
Los antihistamĂnicos antiH1 son, en general, fármacos bien tolerados. Los de primera generaciĂłn cruzan la barrera
hematoencefálica y pueden producir sedación y efectos anticolinérgicos, centrales (confusión, agitación,
etc.…) y perifĂ©ricos (retenciĂłn de orina, sequedad de boca, xerostomĂa). En el caso en el que un paciente precise
tratamiento antihistamĂnico es importante tener en cuenta la carga anticolinĂ©rgica de los fármacos que está
tomando; esto resulta especialmente relevante en pacientes de edad avanzada.
Otro efecto adverso, potencialmente grave, de algunos antihistamĂnicos es la prolongaciĂłn del intervalo QT,
que motivó la retirada del mercado de fármacos como astemizol y terfenadina.
Se ha de tener presente que hay ciertos grupos de poblaciĂłn (embarazadas, mujeres en periodo de lactancia,
edad avanzada, insuficiencia renal y/o hepática y niños) en los que los antihistamĂnicos se deben prescribir con
precaución teniendo en cuenta las recomendaciones de la ficha técnica del fármaco.
En este boletĂn se revisan los antihistamĂnicos disponibles para las principales enfermedades alĂ©rgicas de nuestro
entorno
Gold Nanoparticles as Boron Carriers for Boron Neutron Capture Therapy: Synthesis, Radiolabelling and In Vivo Evaluation
Background: Boron Neutron Capture Therapy (BNCT) is a binary approach to cancer therapy
that requires accumulation of boron atoms preferentially in tumour cells. This can be achieved
by using nanoparticles as boron carriers and taking advantage of the enhanced permeability and
retention (EPR) effect. Here, we present the preparation and characterization of size and shape-tuned
gold NPs (AuNPs) stabilised with polyethylene glycol (PEG) and functionalized with the boron-rich
anion cobalt bis(dicarbollide), commonly known as COSAN. The resulting NPs were radiolabelled
with 124I both at the core and the shell, and were evaluated in vivo in a mouse model of human
fibrosarcoma (HT1080 cells) using positron emission tomography (PET). Methods: The thiolated
COSAN derivatives for subsequent attachment to the gold surface were synthesized by reaction
of COSAN with tetrahydropyran (THP) followed by ring opening using potassium thioacetate
(KSAc). Iodination on one of the boron atoms of the cluster was also carried out to enable subsequent
radiolabelling of the boron cage. AuNPs grafted with mPEG-SH (5 Kda) and thiolated COSAN
were prepared by ligand displacement. Radiolabelling was carried out both at the shell (isotopic
exchange) and at the core (anionic absorption) of the NPs using 124I to enable PET imaging. Results:
Stable gold nanoparticles simultaneously functionalised with PEG and COSAN (PEG-AuNPs@[4])
with hydrodynamic diameter of 37.8 0.5 nm, core diameter of 19.2 1.4 nm and -potential of
18.0 0.7 mV were obtained. The presence of the COSAN on the surface of the NPs was confirmed
by Raman Spectroscopy and UV-Vis spectrophotometry. PEG-AuNPs@[4] could be efficiently
labelled with 124I both at the core and the shell. Biodistribution studies in a xenograft mouse model of
human fibrosarcoma showed major accumulation in liver, lungs and spleen, and poor accumulation
in the tumour. The dual labelling approach confirmed the in vivo stability of the PEG-AuNPs@[4].
Conclusions: PEG stabilized, COSAN-functionalised AuNPs could be synthesized, radiolabelled and
evaluated in vivo using PET. The low tumour accumulation in the animal model assayed points to
the need of tuning the size and geometry of the gold core for future studies
Optimization of the Kinematic Chain of the Thumb for a Hand Prosthesis Based on the Kapandji Opposition Test
Ponènica presentada a International Symposium on Computer Methods in Biomechanics and Biomedical Engineering - CMBBE 2019The thumb plays a key role in the performance of the hand for grasp-ing and manipulating objects. In artificial hands the complex thumb’s kinematic chain (TKC) is simplified and its five degrees of freedom are reduced to only one or two with the consequent loss of dexterity of the hand. The Kapandji op-position test (KOT) has been clinically used in pathological human hands for evaluating the thumb opposition and it has also been employed in some previ-ous studies as reference for the design of the TKC in artificial hands, but with-out a clearly stated methodology. Based on this approaches, in this study we present a computational method to optimize the whole TKC (base placement, link lengths and joint orientation angles) of an artificial hand based on its per-formance in the KOT. The cost function defined for the optimization (MPE) is a weighted mean position error when trying to reproduce the KOT postures and can be used also as a metric to quantify thumb opposition in the hand. As a case study, the method was applied to the improvement of the TKC of an artificial hand developed by the authors and the MPE was reduced to near one third of that of the original design, increasing significantly the number of reachable po-sitions in the KOT. The metric proposed based on the KOT can be used directly or in combination with other to improve the kinematic chain of artificial hands
Phytosterol determination in lipid emulsions for parenteral nutrition
Objective: The presence of phytosterols in vegetal lipid emulsions has been associated with alterations of liver function tests. Determination of phytosterols content, currently undeclared, would allow the development of strategies to prevent or treat these alterations. Method: 3-4 non-consecutive batches of 6 lipid emulsions from diffe rent providers (Clinoleic , Intralipid , Lipofundina , Lipoplus , Omegaven and Smoflipid ) were analyzed. Differences in total phytosterol assay between providers and batches were statistically studied by a one way ANOVA and Kruskal-Wallis non-parametric approximation and post hoc Scheffé test (p<0.05) Results: The absence of phytosterols was confirmed in Omegaven , emulsion based on fish oil. The highest assay of phytosterols (422.4±130.5 µg/mL) has been related with the highest percentage of soya bean oil in Intralipid. In the remaining emulsions, concentrations were from 120 to 210 µg/mL related to the percentage of soya bean oil. Statistically significant differences of phytosterol content in lipid emulsions were observed among different providers (F=23.59; p=0.000) as well as among non-consecutive batches. Clinolenic (F=23.59; p=0.000), Intralipid (F=978.25; p=0.000), Lipofundina TCL/TCM (F=5.43; p=0.045), Lipoplus (F=123.53; p=0.000) and Smoflipid (16.78; p=0.000). Except for Lipofundina TCL/TCM, the differences between batches were marked. Conclusions: Lipid emulsions, registered on Spanish pharmaceutical market, contain variable quantities of phytosterols dependent on commer cial brand and batch
Advanced technologies for the improvement of spray application techniques in spanish viticulture: an overview
Spraying techniques have been undergoing continuous evolution in recent decades. This paper presents part of the research work carried out in Spain in the field of sensors for characterizing vineyard canopies and monitoring spray drift in order to improve vineyard spraying and make it more sustainable. Some methods and geostatistical procedures for mapping vineyard parameters are proposed, and the development of a variable rate sprayer is described. All these technologies are interesting in terms of adjusting the amount of pesticides applied to the target canopy.Postprint (published version
High-contrast spectroscopy testbed for segmented telescopes
The High Contrast Spectroscopy Testbed for Segmented Telescopes (HCST) at Caltech is aimed at filling gaps in technology for future exoplanet imagers and providing the U.S. community with an academic facility to test components and techniques for high contrast imaging with future segmented ground-based telescope (TMT, E-ELT) and space-based telescopes (HabEx, LUVOIR). The HCST will be able to simulate segmented telescope geometries up to 1021 hexagonal segments and time-varying external wavefront disturbances. It also contains a wavefront corrector module based on two deformable mirrors followed by a classical 3-plane single-stage corona- graph (entrance apodizer, focal-plane mask, Lyot stop) and a science instrument. The back-end instrument will consist of an imaging detector and a high-resolution spectrograph, which is a unique feature of the HCST. The spectrograph instrument will utilize spectral information to characterize simulated planets at the photon-noise limit, measure the chromaticity of new optimized coronagraph and wavefront control concepts, and test the overall scientific functions of high-resolution spectrographs on future segmented telescopes
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