88 resultados para release paper


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After the release of the gamma-ray source catalog produced by the Fermi satellite during its first two years of operation, a significant fraction of sources still remain unassociated at lower energies. In addition to well-known high-energy emitters (pulsars, blazars, supernova remnants, etc.), theoretical expectations predict new classes of gamma-ray sources. In particular, gamma-ray emission could be associated with some of the early phases of stellar evolution, but this interesting possibility is still poorly understood. Aims: The aim of this paper is to assess the possibility of the Fermi gamma-ray source 2FGL J0607.5-0618c being associated with the massive star forming region Monoceros R2. Methods: A multi-wavelength analysis of the Monoceros R2 region is carried out using archival data at radio, infrared, X-ray, and gamma-ray wavelengths. The resulting observational properties are used to estimate the physical parameters needed to test the different physical scenarios. Results: We confirm the 2FGL J0607.5-0618c detection with improved confidence over the Fermi two-year catalog. We find that a combined effect of the multiple young stellar objects in Monoceros R2 is a viable picture for the nature of the source.

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SEPServer is a three-year collaborative project funded by the seventh framework programme (FP7-SPACE) of the European Union. The objective of the project is to provide access to state-of-the-art observations and analysis tools for the scientific community on solar energetic particle (SEP) events and related electromagnetic (EM) emissions. The project will eventually lead to better understanding of the particle acceleration and transport processes at the Sun and in the inner heliosphere. These processes lead to SEP events that form one of the key elements of space weather. In this paper we present the first results from the systematic analysis work performed on the following datasets: SOHO/ERNE, SOHO/EPHIN, ACE/EPAM, Wind/WAVES and GOES X-rays. A catalogue of SEP events at 1 AU, with complete coverage over solar cycle 23, based on high-energy (~68-MeV) protons from SOHO/ERNE and electron recordings of the events by SOHO/EPHIN and ACE/EPAM are presented. A total of 115 energetic particle events have been identified and analysed using velocity dispersion analysis (VDA) for protons and time-shifting analysis (TSA) for electrons and protons in order to infer the SEP release times at the Sun. EM observations during the times of the SEP event onset have been gathered and compared to the release time estimates of particles. Data from those events that occurred during the European day-time, i.e., those that also have observations from ground-based observatories included in SEPServer, are listed and a preliminary analysis of their associations is presented. We find that VDA results for protons can be a useful tool for the analysis of proton release times, but if the derived proton path length is out of a range of 1 AU < s[3 AU, the result of the analysis may be compromised, as indicated by the anti-correlation of the derived path length and release time delay from the asso ciated X-ray flare. The average path length derived from VDA is about 1.9 times the nominal length of the spiral magnetic field line. This implies that the path length of first-arriving MeV to deka-MeV protons is affected by interplanetary scattering. TSA of near-relativistic electrons results in a release time that shows significant scatter with respect to the EM emissions but with a trend of being delayed more with increasing distance between the flare and the nominal footpoint of the Earth-connected field line.

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Self-nanoemulsifying drug delivery systems of gemfibrozil were developed under Quality by Design approach for improvement of dissolution and oral absorption. Preliminary screening was performed to select proper components combination. BoxBehnken experimental design was employed as statistical tool to optimize the formulation variables, X1 (Cremophor® EL), X2 (Capmul® MCM-C8), and X3 (lemon essential oil). Systems were assessed for visual characteristics (emulsification efficacy), turbidity, droplet size, polydispersity index and drug release. Different pH media were also assayed for optimization. Following optimization, the values of formulation components (X1, X2, and X3) were 32.43%, 29.73% and 21.62%, respectively (16.22% of gemfibrozil). Transmission electron microscopy demonstrated spherical droplet morphology. SNEEDS release study was compared to commercial tablets. Optimized SNEDDS formulation of gemfibrozil showed a significant increase in dissolution rate compared to conventional tablets. Both formulations followed Weibull mathematical model release with a significant difference in td parameter in favor of the SNEDDS. Equally amodelistic parameters were calculated being the dissolution efficiency significantly higher for SNEDDS, confirming that the developed SNEDDS formulation was superior to commercial formulation with respect to in vitro dissolution profile. This paper provides an overview of the SNEDDS of the gemfibrozil as a promising alternative to improve oral absorption.

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Parlar de Lluís Solé Sabarís com a geògraf és una tasca que ultrapassa de molt les meves possibilitats, ja que no es tracta simplement d'escorcollar els aspectes mes geografics d'un geòleg. Ans al contrari, sense voler prejutjar la seva tasca immensa en el camp de la Geologia, cal dir tot seguit que Solé Sabarís és ell mateix un geògraf. Efectivament, des de les seves classes de Geografia a 1'Institut-escola «Giner de los Ríos» de la Generalitat a les seves activitats mes recents com a president de la Societat Catalana de Geografia, passant pel seu mestratge a tants de geografs al Consejo Superior de Investigaciones Científicas de Barcelona o als cursets de Pirineus, o per bona part de les seves obres i escrits, arreu hi podem trobar l'alenar de tot un geògraf de l'escola francesa. L'anàlisi de tota aquesta tasca ultrapassa de molt les meves possibilitats. Moltes coses són encara massa recents, i de testimonis més qualificats n'hi ha també molts d'altres.

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S u b s u r face fluid flow plays a significant role in many geologic processes and is increasingly being studied in the scale of sedimentary basins and geologic time perspective. Many economic resources such as petroleum and mineral deposits are products of basin scale fluid flow operating over large periods of time. Such ancient flow systems can be studied through analysis of diagenetic alterations and fluid inclusions to constrain physical and chemical conditions of fluids and rocks during their paleohy d r og e o l ogic evolution. Basin simulation models are useful to complement the paleohy d r og e o l ogic record preserved in the rocks and to derive conceptual models on hydraulic basin evolution and generation of economic resources. Different types of fluid flow regimes may evo l ve during basin evolution. The most important with respect to flow rates and capacity for transport of solutes and thermal energy is gr avitational fluid flow driven by the topographic configuration of a basin. Such flow systems require the basin to be elevated above sea level. Consolidational fluid flow is the principal fluid migration process in basins below sea level, caused by loading of compressible rocks. Flow rates of such systems are several orders of magnitude below topogr a p hy driven flow. Howeve r, consolidation may create significant fluid ove rpressure. Episodic dewatering of ove rpressured compart m e n t s m ay cause sudden fluid release with elevated flow velocities and may cause a transient local thermal and chemical disequilibrium betwe e n fluid and rock. This paper gives an ove rv i ew on subsurface fluid flow processes at basin scale and presents examples related to the Pe n e d è s basin in the central Catalan continental margin including the offshore Barcelona half-graben and the compressive South-Pyrenean basin.

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Chemical perception is considered one of the first senses used as a communication system between living organisms. Such communication is based on the emission of signals between a sender and a receiver; if the communication is chemical, these signals are called pheromones. These signals have evolved via natural selection through a mechanism known as ritualization, which converts cues (which are not adapted to communication and which the receiver picks up regardless of the interests of the sender) into signals (information that the sender transmits as an adaptative response to its previously developed perception of the receiver). When communication has evolved between actors (sender and receiver) with common interests, the honesty of the signal is taken for granted, since both want the same thing (i.e., there is no reason to deceive). If the actors have conflicting interests, however, then the possibility of deception seeps into the possible array of adaptations. This can be observed in the case of communicative mimicry. However, in other situations natural selection imposes conditions that screen the possible signals, allowing only those that meet the requirement of honesty to stabilize. These include indices and added-cost signals. The emission of pheromones plays a variety of roles in the life processes of living beings. It facilitates encounters between individuals of the same species and is heavily involved in the mechanisms of recognition of relatives. It also fosters behaviours such as altruism (cooperation between individuals that share a percentage of their genetic inheritance). In many species, including humans, chemical communication works behind the scenes to guide the choice of a sexual partner.

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Dissolution studies have become of great significance because, in most cases, drug dissolution is the rate-limiting step in the absorption process. As occurs with solid oral dosage forms, heterogeneous disperse systems (suspensions) could also have some problems with their in vitro dissolution. The objective of this study was to evaluate influence of the excipients on the release of spironolactone from four alcohol free suspensions (pharmaceutical compounding) of spironolactone 5 mg/mL suitable for pediatric use. Also the comparison of the physical and chemical stability of the suspensions stored at 4, 25 and 40 ºC over a 60- day period has been studied. Rheological behavior, particle size, a prediction of long-term physical stability, pH and assay of spironolactone by HPLC were assessed at prefixed times. The dissolution profile of each suspension was determined and compared with that of the commercial tablets. A microbiological study of the best formula was also performed. Chemically, the four spironolactone suspensions were stable for 60 days stored at three temperatures; Suspension IV had optimum pH values and the highest recovery percentage. In terms of physical stability, sedimentation occurred in Suspension IV and flotation of spironolactone in Suspensions I, II and III. Suspension III had the highest viscosity and the slowest drug release. Suspension IV was also microbiologically stable for 60 days. In conclusion, Suspension IV had the best properties and the least suitable form was Suspension III, as its high viscosity made it difficult to achieve homogeneous redispersion, and it had the slowest dissolution profile.

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El creixent ritme d’exportacions del Brasil, fa que la demanda de papers d’embalatges’incrementi constantment. El material més utilitzat per al transport són les caixes de cartróondulat (OCC). Aquestes caixes, quan se’ls acaba la vida útil, són recuperades per afabricar nou cartró ondulat. El paper de diari, que un cop llegit es converteix en un residu, nos’acostuma a utilitzar per a la fabricació de nous productes paperers, tot i estar fabricat ambfibres de qualitat elevada.Amb la utilització d’aquests materials com a alternativa es disminueix la demanda defibres verges com és el pi, que al Brasil, es troba en una situació crítica a causa de la malagestió de les plantacions.Cal dir que la part pràctica de l’estudi, que consisteix bàsicament en treball de laboratori,ha estat realitzada al Brasil, d’on provenen també les matèries primeres utilitzades. Peraquest motiu, el context de l’estudi està centrat en el mercat, en les necessitats i en larealitat d’aquest país.Aquest projecte té com a objectiu determinar la composició òptima d’una barreja depastes de pi, sisal, retalls i paper de diari, per a la fabricació de paper tripa industrial. Aquestpaper és el que es col•loca, ondulat, enmig de les capes externes del cartró multicapa

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El present estudi pretén posar en valor part del paper de l’Home del Programa MaB (Men and Biosphere). En concret, pretén descobrir la importància i el paper que pot tenir (o que té realment) l’anomenat patrimoni cultural per a la consecució dels objectius de la Reserva de la Biosfera, i les pròpies potencialitats que ofereix aquest patrimoni per al consum del turisme cultural

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La dona és cada vegada més present en el món de la comunicació publicitària, però avui en dia, la seva presència encara segueix essent mínima en els departaments de creativitat. En una primera part es pretén reflectir la realitat laboral i social que empeny la participació de la dona en el món publicitari, al mateix temps que un sostre de vidre imperceptible frena la seva presència en llocs de rellevància. En una segona part, s’analitza quins canvis o tendències pot suposar aquesta escalada de la dona en llocs de direcció i creativitat.

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The disintegration of recovered paper is the first operation in the preparation of recycled pulp. It is known that the defibering process follows a first order kinetics from which it is possible to obtain the disintegration kinetic constant (KD) by means of different ways. The disintegration constant can be obtained from the Somerville index results (%lsv and from the dissipated energy per volume unit (Ss). The %slv is related to the quantity of non-defibrated paper, as a measure of the non-disintegrated fiber residual (percentage of flakes), which is expressed in disintegration time units. In this work, disintegration kinetics from recycled coated paper has been evaluated, working at 20 revise rotor speed and for different fiber consistency (6, 8, 10, 12 and 14%). The results showed that the values of experimental disintegration kinetic constant, Ko, through the analysis of Somerville index, as function of time. Increased, the disintegration time was drastically reduced. The calculation of the disintegration kinetic constant (modelled Ko), extracted from the Rayleigh’s dissipation function, showed a good correlation with the experimental values using the evolution of the Somerville index or with the dissipated energy

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Aquest treball es basa en les pràctiques realitzades dins del marc del Màster en Envelliment Actiu de la Universitat de Vic. L’objectiu d’aquestes pràctiques era doble: per una banda, aprofundir en el coneixement del rol del psicogerontòleg en un centre sociosanitari d’atenció a la gent gran i, per l’altra, elaborar, aplicar i avaluar una intervenció per fomentar l’envelliment actiu. És a dir, es pretenia donar cobertura a les dues grans àrees d’intervenció a les quals ha de fer front el psicogerontòleg en l’actualitat, com veurem més endavant, i que són: l’atenció a la dependència i la promoció de l’envelliment actiu, tenint en compte que aquesta darrera suposa la prevenció de la malaltia i la discapacitat i la maximització del benestar i la qualitat de vida en la vellesa.

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The spread of sociocultural focuses and critical literacy studies, which offer an holistic perspective on communicative skills, has reached our country at a time when the commonest environment for writing is the internet, and information technologies have transformed writing with new channels, genres, forms of preparation and languages. Thanks to these changes, educational programmes now include new concepts of literacy related to knowledge and the use of digital environments. This paper explores the impact of introducing these new communicative environments to teaching written expression at secondary level and puts forward some ideas to link learning how to write to present communicative contexts and established practices. Without forgetting the achievements of recent decades, we need to bring about a series of changes to bring new learned writing practices to class and leave behind others we had championed as necessary when the goal was to move beyond exclusively linguistic or grammatical approaches