753 resultados para cellulose solution in ionic liquids


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Hansen's Bacillus: By electron microscopy this bacillus shows membrane and halo, this being more visible when sorrounding the globi or bundles of bacilli; shows, also, free granules of various sizes which were before considered as dust of the dyes; shows external granules bound with the membrane and some times branching. By phases contrast microscopy examining leproma suspensions and subcataneous lymph at 400 x we saw many free granules with intense rotatory movement; granulated bacilli with screw, skip or stroke motion, producing slow progressive motion. All such elementes are surrounded by a halo, corresponding to the classical gloea. By a patient and delayed examination we were able to see that the internal granules are motile and help the progression of the bacilli, giving the impression that the cytoplasm is liquid. By a lasting observation we could see the larger granules form prolapse, like a pseudopode and abandon the bacilli and going in very rapid rotatory movement. There are branched bacilli; there are pedunculated fred granules like comets. The addition of a drop of formol at the preparation stops all movements. Stefansky's Bacillus: Repeated examination by RCA electron microscope, type EMU-25 of fresh suspensions of rat lepromas, led us to confirm the close relationship between human and murine leprosy agents. We examined also material from carabo (Lepra bubalorum) from Java, but due to fixation, the material was unsuitable for comparative studies. The Stefansky's bacilli showed also emmbranes and halos, internal or external granules (smaller than those of Hansen's bacillus). The bacilli shaded by chromium look thicker and shorter than those of Hansen. Due to electron bombardment both, Hansen's and Stefansky's baccilli suffer considerable alterations in their structure, showing black barrs of chromatin condensation at their extremities as also in their centers. By phase microscopy the Stefansky's bacilli showed elements with 1, 2 (bipolar), 3 or more internal small granules, developing identical movements as those of Hansen. The globi seem to be non-motile but the free bacilli appearing around the globi show intense movement. At 1000 x the examination is less satisfactory than at 400 x. The addition of formol solution in the preparation suppresses all movements, even the brownian, but the material becomes more suitable for the study of static morphology of the bacilli. CONCLUSION - The electron and phases contrast microscopy of leprous material from different types and phases of the disease may explain some of the unknown aspects of the biology and morphology of the bacilli.

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Aquest projecte presenta una sol·lució per tal d’incorporar una eina wiki al Campus Virtual de la Universitat Autònoma de Barcelona. Enfront de la metodologia docent clàssica, la wiki oferirà funcionalitats orientades al treball col·laboratiu i fomentarà la participació de l’alumne. L’objectiu final és tenir una eina completament integrada al Campus Virtual, que aprofiti l’aplicatiu existent i s’interrelacioni amb la resta de mòduls presents.

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Accidental transmission of Chagas' disease to man by blood transfusion is a serious problem in Latin-America. This paper describes the testing of several synthetic, semi-synthetic, and natural compounds for their activity against blood trypomastigotes in vitro at 4-C. The compounds embody several types of chemical structures: benzoquinone, naphthoquinone, anthracenequinone, phenanthrenequinone, imidazole, piperazine, quinoline, xanthene, and simple benzenic and naphthalenic derivates. Some of them are for the first time tested against Trypanosoma cruzi. The toxic effect these compounds on this parasite was done by two quite distinct sets of experiments. In one set, the compounds were added to infected blood as ethanolic solution. In this situation the most active one was a furan-1, 2-naphthoquinone, in the same range as gentian violet, a new fact to be considered in the assessment of structure-activity relationships in this class of compounds. In other set, we tentatively evaluated the biological activity of water insoluble compounds by adding them in a pure form without solvent into infected blood. In this way some appear to be very active and it was postulated that the effectiveness of such compounds must result from interactions between them and specific blood components.

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When using a polynomial approximating function the most contentious aspect of the Heat Balance Integral Method is the choice of power of the highest order term. In this paper we employ a method recently developed for thermal problems, where the exponent is determined during the solution process, to analyse Stefan problems. This is achieved by minimising an error function. The solution requires no knowledge of an exact solution and generally produces significantly better results than all previous HBI models. The method is illustrated by first applying it to standard thermal problems. A Stefan problem with an analytical solution is then discussed and results compared to the approximate solution. An ablation problem is also analysed and results compared against a numerical solution. In both examples the agreement is excellent. A Stefan problem where the boundary temperature increases exponentially is analysed. This highlights the difficulties that can be encountered with a time dependent boundary condition. Finally, melting with a time-dependent flux is briefly analysed without applying analytical or numerical results to assess the accuracy.

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Els canvi recents en els plans d’estudis de la UPC i la UOC tenen en compte el nou espai europeu d’educació superior (EEES). Una de les conseqüències directes a aquests canvis es la necessitat d'aprofitar i optimitzar el temps dedicat a les activitats d'aprenentatge que requereixen la participació activa de l’estudiant i que es realitzen de manera continuada durant el semestre. A més, I'EEES destaca la importància de les pràctiques, les relacions interpersonals i la capacitat per treballar en equip, suggerint la reducció de classes magistrals i l’augment d’activitats que fomentin tant el treball personal de l’estudiant com el cooperatiu. En l’àmbit de la docència informàtica d’assignatures de bases de dades el problema és especialment complex degut a que els enunciats de les proves no acostumen a tenir una solució única. Nosaltres hem desenvolupat una eina anomenada LEARN-SQL, l’objectiu de la qual és corregir automàticament qualsevol tipus de sentència SQL (consultes, actualitzacions, procediments emmagatzemats, disparadors, etc.) i discernir si la resposta aportada per l’estudiant és o no és correcta amb independència de la solució concreta que aquest proposi. D’aquesta manera potenciem l’autoaprenentatge i l’autoavaluació, fent possible la semi-presencialitat supervisada i facilitant l’aprenentatge individualitzat segons les necessitats de cada estudiant. Addicionalment, aquesta eina ajuda als professors a dissenyar les proves d’avaluació, permetent també la opció de revisar qualitativament les solucions aportades pels estudiants. Per últim, el sistema proporciona ajuda als estudiants per a que aprenguin dels seus propis errors, proporcionant retroalimentació de qualitat.

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Als darrers anys la necessitat de connectar-se a internet des de qualsevol lloc s’ha incrementat exponencialment sobretot de manera inalàmbrica. Degut al finit espectre radioelèctric es tendeix a aprofitar totes les franges freqüencials d’aquest convivint diferents sistemes en franges properes podent induir-se interferències mútuament. Per evitar aquestes interferències es requereix de filtres a tots els dispositius els quals aïllin un sistema del adjacent. En aquest projecte es dóna una solució al cas concret de la convivència entre els sistemes Wi-Fi y WiMAX eliminant la banda Wi-Fi interferent en sistemes WiMAX. Aquesta solució consisteix en el disseny d’un filtre banda eliminada d’ordre 3 implementat mitjançant tecnologia BAW a partir de l’estructura y especificacions d’un filtre comercial. A més també es fa un petit estudi per veure si seria interessant una millora en els processos de fabricació del filtre per part del fabricant.

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L'objectiu primari del projecte recau en la capacitat de connectar dos nodes amb connexió a xarxa, tant si és una simple LAN com si es tracta d'Internet, i fer possible d'establir-hi una comunicació bidireccional emprant el concepte de missatgeria instantània. L'objectiu secundari consisteix a estudiar el motor de comunicació distribuïda que ofereix LaCOLLA, i també la connexió de l'aplicació desenvolupada amb aquesta solució a fi d'emprar-la com a suport de comunicació.

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L'objectiu d'aquest projecte és estudiar i implementar una solució segura de connectivitat sense fil a la infraestructura actual aprofitant al màxim tots els sistemes ja implementats, de manera que no pateixin greus canvis estructurals.

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Es vol proporcionar una solució en el camp de la sanitat perquè els metges puguin gestionar els historials mèdics dels seus pacients de forma remota i segura, i perquè els pacients puguin consultar la seva història mèdica també remotament i amb total seguretat en qualsevol moment i ubicació.

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The adjustment of the teaching learning contents in Physical Education, requires of a rigorous analysis that permits to adjust them to the maximum with the educational needs of the student body. It has been approached an investigation study in the one which have intervened pupils, boys and girls, of two different populations, Girona and Madrid in order to prove and analyse the motor and mental components of the student body in the real situation of the game. The hypothesis that we have treated are:if it exists differences between the boys and girls of the educational levels studied in the motor and mental solution in the sports initiation, additionally, the differences that they can exist between the courses and what distance is verified between the study ages to approach a physical activity that implies an initial step to the hour of teaching the collective sports in the classes of Physical education. They have been employed three measure instruments: the first permits to analyse the mental solution without need of practice employing situation photographs of the real game with those which the pupils must choose to who to happen; the second is a pass test that permits to prove the technical dominance to use in a collective sport and the third is a real game situation that permits to put in manifesto the relationship between the mental behaviour and the motor of the pupil. This real game situation is ‘the game of ten pass’ (Blázquez,1986; Torres,1993). The results demonstrate that it do not exist differences between the two sexes in the study ages. In the case of the technical execution level, there is a considerable increase with the age and it is slightly greater in the kids that in the girls. In the case of the real game, we find ourselves with a great variability in the results and we cannot conclude that there are relative differences to the sex in none of the three courses. Respect at participation level during the game is confirmed that the pupils that more participate are not the pupils than more balls lose, what permits to guarantee the idea of the fact that it is convenient to use the real game practice as direct learning element. Finally, there is no a high correlation between the execution level measured in the test of technical execution and the decision execution during the game

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This paper proposes a parallel architecture for estimation of the motion of an underwater robot. It is well known that image processing requires a huge amount of computation, mainly at low-level processing where the algorithms are dealing with a great number of data. In a motion estimation algorithm, correspondences between two images have to be solved at the low level. In the underwater imaging, normalised correlation can be a solution in the presence of non-uniform illumination. Due to its regular processing scheme, parallel implementation of the correspondence problem can be an adequate approach to reduce the computation time. Taking into consideration the complexity of the normalised correlation criteria, a new approach using parallel organisation of every processor from the architecture is proposed

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The production of fibrinous exudates may play an important role in determining the outcome of bacterial infection. Although pseudomembrane formation is a characteristic feature of diphtheria, little is known about the fibrinogen (Fbn)-binding properties of Corynebacterium diphtheriae strains and the influence of the gene that codes for diphtheria toxin (tox gene) in this process. In this study we demonstrated the ability of C. diphtheriae strains to bind to Fbn and to convert Fbn to fibrin. Bacterial interaction with rabbit plasma was evaluated by both slide and tube tests. Interaction of microorganisms with human Fbn was evaluated by both enzyme linked immunosorbent assay (ELISA) and fluorescein isothiocyanate-conjugated (FITC) Fbn binding assays. Nontoxigenic and toxigenic strains formed bacterial aggregates in the presence of plasma in the slide tests. The ability to convert Fbn to a loose web of fibrin in the plasma solution in the tube tests appeared to be a common characteristic of the species, including strains that do not carry the tox gene. Fbn binding to C. diphtheriae strains occurred at varying intensities, as demonstrated by the FITC-Fbn and ELISA binding assays. Our data suggest that the capacity to bind to Fbn and to convert Fbn to fibrin may play a role in pseudomembrane formation and act as virulence determinants of both nontoxigenic and toxigenic strains.

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The epithelial Na(+) channel (ENaC), located in the apical membrane of tight epithelia, allows vectorial Na(+) absorption. The amiloride-sensitive ENaC is highly selective for Na(+) and Li(+) ions. There is growing evidence that the short stretch of amino acid residues (preM2) preceding the putative second transmembrane domain M2 forms the outer channel pore with the amiloride binding site and the narrow ion-selective region of the pore. We have shown previously that mutations of the alphaS589 residue in the preM2 segment change the ion selectivity, making the channel permeant to K(+) ions. To understand the molecular basis of this important change in ionic selectivity, we have substituted alphaS589 with amino acids of different sizes and physicochemical properties. Here, we show that the molecular cutoff of the channel pore for inorganic and organic cations increases with the size of the amino acid residue at position alpha589, indicating that alphaS589 mutations enlarge the pore at the selectivity filter. Mutants with an increased permeability to large cations show a decrease in the ENaC unitary conductance of small cations such as Na(+) and Li(+). These findings demonstrate the critical role of the pore size at the alphaS589 residue for the selectivity properties of ENaC. Our data are consistent with the main chain carbonyl oxygens of the alphaS589 residues lining the channel pore at the selectivity filter with their side chain pointing away from the pore lumen. We propose that the alphaS589 side chain is oriented toward the subunit-subunit interface and that substitution of alphaS589 by larger residues increases the pore diameter by adding extra volume at the subunit-subunit interface.

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We have shown previously that voluntary ethanol consumption and resistance to ethanol-induced sedation are inversely related to neuropeptide Y (NPY) levels in NPY-knock-out (NPY(-/-)) and NPY-overexpressing mice. In the present report, we studied knock-out mice completely lacking the NPY Y1 receptor (Y1(-/-)) to further characterize the role of the NPY system in ethanol consumption and neurobiological responses to this drug. Here we report that male Y1(-/-) mice showed increased consumption of solutions containing 3, 6, and 10% (v/v) ethanol when compared with wild-type (Y1(+/+)) control mice. Female Y1(-/-) mice showed increased consumption of a 10% ethanol solution. In contrast, Y1(-/-) mice showed normal consumption of solutions containing either sucrose or quinine. Relative to Y1(+/+) mice, male Y1(-/-) mice were found to be less sensitive to the sedative effects of 3.5 and 4.0 gm/kg ethanol as measured by more rapid recovery from ethanol-induced sleep, although plasma ethanol levels did not differ significantly between the genotypes. Finally, male Y1(-/-) mice showed normal ethanol-induced ataxia on the rotarod test after administration of a 2.5 gm/kg dose. These data suggest that the NPY Y1 receptor regulates voluntary ethanol consumption and some of the intoxicating effects caused by administration of ethanol.

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This thesis focuses on stage fright; what it is and how to find the ideal solution in connection with stage fright. To find the way toward free expression; to find the way from lack of control to con-trol. It also describes how to learn to live with stage fright. Different experiences of stage fright have been used as source material, along with relevant theoretical information. The thesis highlights the importance of handling stage fright and studies stage fright in-depth, with examples. It presents studies and collected theories according to Päivi Arjas. It discusses presence and contact in the work of an actor with reference to the Gestalt method. It also presents methods of reducing stage fright. Ideal presence on stage is addressed, and how to turn stage fright into a positive thing. Finally, it considers the good aspects of stage fright in more deepth and goes through learning to live with stage fright. The thesis concludes that it is possible to heal stage fright. Gestalt methodology was of assistance with the healing process, with becoming conscious of symptoms, and thus in finding one's own way of turning anxious suspense into a positive way forward.