876 resultados para step motors
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This study proposes a theoretical model describing the electrostatically driven step of the alpha 1 b-adrenergic receptor (AR)-G protein recognition. The comparative analysis of the structural-dynamics features of functionally different receptor forms, i.e., the wild type (ground state) and its constitutively active mutants D142A and A293E, was instrumental to gain insight on the receptor-G protein electrostatic and steric complementarity. Rigid body docking simulations between the different forms of the alpha 1 b-AR and the heterotrimeric G alpha q, G alpha s, G alpha i1, and G alpha t suggest that the cytosolic crevice shared by the active receptor and including the second and the third intracellular loops as well as the cytosolic extension of helices 5 and 6, represents the receptor surface with docking complementarity with the G protein. On the other hand, the G protein solvent-exposed portions that recognize the intracellular loops of the activated receptors are the N-terminal portion of alpha 3, alpha G, the alpha G/alpha 4 loop, alpha 4, the alpha 4/beta 6 loop, alpha 5, and the C-terminus. Docking simulations suggest that the two constitutively active mutants D142A and A293E recognize different G proteins with similar selectivity orders, i.e., G alpha q approximately equal to G alpha s > G alpha i > G alpha t. The theoretical models herein proposed might provide useful suggestions for new experiments aiming at exploring the receptor-G protein interface.
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This workbook aims to help people who use alcohol or drugs to think about the importance of eating well and find ways to achieve a more balanced diet.
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Immediate prevention of meningococcal disease relies in part on the prompt treatment with antibiotics of household and other close contacts of cases; however intervention with effective vaccination relies on identification of serogroup-causing strains. Parenteral antibiotic for patient with suspected meningococcal disease before hospital admission is currently recommended. Laboratory standard methods are hindered by failure to detect bacteria by this medical approach to improve patient prognosis. We assessed two polymerase chain reaction (PCR) assays to detect (crgA) and define the serogroups (siaD, orf-2, and ctrA) of Neisseria meningitidis in 120 cerebrospinal fluid (CSF) samples from positive cases (culture or antigen detection or direct smear). The PCR sensitivity for the identification of N. meningitidis was 100% (95% confidence interval, CI, 96-100%) compared to a sensitivity of 46% for culture (95% CI 37-55%), 61% for latex agglutination test (95% CI 52-70%), and 68% for Gram stain (95% CI 59-76%); PCR specificity was 97% (95% CI 82-100%). PCR correctly identified the serogroups A, B, C, W135, Y, and X in CSF samples with a sensitivity of 88% (95% CI 80-93%); the primer sets were 100% specific. The introduction of PCR-based assays shall increase laboratory confirmed cases, consequently enhancing surveillance of meningococcal disease.
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This leaflet provides information on further investigations participants may require, including colonoscopy.The translations are of the 2010 versions when screening was for 60��-69 year olds but this has been extended to 60��-74 year olds.
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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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In this paper a novel methodology aimed at minimizing the probability of network failure and the failure impact (in terms of QoS degradation) while optimizing the resource consumption is introduced. A detailed study of MPLS recovery techniques and their GMPLS extensions are also presented. In this scenario, some features for reducing the failure impact and offering minimum failure probabilities at the same time are also analyzed. Novel two-step routing algorithms using this methodology are proposed. Results show that these methods offer high protection levels with optimal resource consumption
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A la física o a l’enginyeria es defineix com fregament o fricció a la resistència que s'oposa a la rotació o al lliscament d'un cos sobre un altre, o també a la força que apareix en la superfície de contacte de dos cossos quan s'intenta lliscar un sobre un altre. El fregament ha estat fins avui dia un gran problema físic, això és degut a que genera imperfeccions, especialment microscòpiques, entre les superfícies en contacte. Aleshores és quan apareix la tribologia. La tribologia és la ciència que estudia la fricció, el desgast i la lubricació de superfícies en contacte. El lliscament entre superfícies sòlides es caracteritza generalment per un alt coeficient de fricció i un gran desgast a causa de les propietats específiques de lessuperfícies. La lubricació consisteix en la introducció d'una capa intermèdia d'un material aliè entre les superfícies en moviment. En aquest projecte hem intentat aplicar tècniques i mètodes de control els quals puguin arribar a millorar i perfeccionar els sistemes de mesura i control a nivell industrial i/o particular. En el nostre cas ha estat l’estudi dels olis lubricants usats en motors de combustió interna de variats vehicles com motocicletes, automòbils, camions o vaixells. Hem introduït una millora d’automatització mitjançant un circuit pneumàtic al captador de partícules, hi hem introduït una tècnica per captar partícules a partir de filtres de membrana, hem estudiat les mostres i llurs ferrogrames i membranes amb la finalitat de detectar les anomalies dels motors. L’objectiu del treball és l’estudi del desgast originat en motors de combustió interna, majoritàriament, Dièsel de camions, automòbils i vaixells. Això, comprèn la captació de partícules en ferrografies, la seva observació i anàlisi en microscopi, la seva classificació, comparació i la detecció d’anomalies en els motors. Per altra banda, també s’aprofundirà en les tècniques d’anàlisi, la lubricació i manteniment dels motors i el nou disseny i validació d’un captador de partícules automatitzat
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En el món dels videojocs el realisme és un punt molt important a tenir en compte ja que dónamés sensació a l’usuari d’estar immers en el videojoc. Això passa en part per aconseguir realisme en la dinàmica dels objectes i fer que aquests segueixin les lleis de la física de Newton. Per això s’han desenvolupat diverses llibreries que s’anomenen “motors de física” (physics engines), que empren variables com la massa, la velocitat, la fricció i la resistència del vent. Els objectius d’aquest projecte seran l’estudi de diferents llibreries físiques existents, la seva comparació i com s’integren en els motors de jocs. A més a més , la generació de contingut amb comportament que respongui a les funcions definides a aquestes llibreries no és trivial i per aquest motiu també es desenvoluparà una aplicació per generar murs de forma semiautomàtica que respongui a impactes. Per assolir aquests objectius caldrà: d’ una banda, comparar els cossos rígids, unions i funcionament en general de diferents llibreries físiques: Newton Game Dynamics, NVIDIA PhysX Technology, Open Dynamics Engine, Bullet PhysicsLibrary, Tokamak Physics Engine i Havok i d’ altra banda, implementar una aplicació que donant-li una imatge en planta d’una paret o conjunt de parets en format vectorial i les mides d’un maó, generi murs que puguin reaccionar de forma adequada quan rebin l’impacte d’una massa determinada. L’aplicació s’implementarà en C++ i amb l’entorn de desenvolupament Microsoft Visual Studio 2005. La visualització serà amb OpenGL
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La pose d'un cathéter veineux central peut se faire par plusieurs abords. La connaissance de l'anatomie, du matériel, la maîtrise des détails de la procédure pour chaque type d'abord et une attention particulière à l'asepsie sont des prérequis importants pour limiter les risques de complications et pour donner une information complète et exhaustive au patient. Cet article peut être utilisé comme base pour le développement d'une check-list, utile pour les médecins qui doivent procéder à la pose d'un cathéter veineux central mais qui ne possèdent pas encore une maîtrise du geste. Several approaches exist for central vein catheterization. Mastery of the various steps of this procedure and understanding of the basics of asepsis are critical to prevent any complication. They also built the basis for an exhaustive communication with the patient, to obtain an informed consent. This article can in addition be used to develop a checklist in order to (self-)assess competence in procedural skills
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In this tutorial review, we detail both the rationale for as well as the implementation of a set of analyses of surface-recorded event-related potentials (ERPs) that uses the reference-free spatial (i.e. topographic) information available from high-density electrode montages to render statistical information concerning modulations in response strength, latency, and topography both between and within experimental conditions. In these and other ways these topographic analysis methods allow the experimenter to glean additional information and neurophysiologic interpretability beyond what is available from canonical waveform analyses. In this tutorial we present the example of somatosensory evoked potentials (SEPs) in response to stimulation of each hand to illustrate these points. For each step of these analyses, we provide the reader with both a conceptual and mathematical description of how the analysis is carried out, what it yields, and how to interpret its statistical outcome. We show that these topographic analysis methods are intuitive and easy-to-use approaches that can remove much of the guesswork often confronting ERP researchers and also assist in identifying the information contained within high-density ERP datasets.
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The aim of this paper is to analyse the main agreements on the EU’s External Action agreed within the European Convention and the IGC taking into account why, how and who reached the consensus on them. In other words, this paper will explore the principles followed in order to improve the instruments of the EU’s External Action such as authority, coherence, visibility, efficiency and credibility.
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Poor compliance with antihypertensive drug regimens is one recognized cause of inadequate blood pressure control. Compliance is difficult to measure, so poor adherence to treatment remains largely undiagnosed in clinical practice. When the therapeutic response to a drug is not the one expected, it is a major challenge for many physicians to decide whether the patient is a non-responder or a non-complier. Poor compliance is therefore often incorrectly interpreted as a lack of response to treatment. Not detecting non-compliance can lead to the wrong measures being taken. Electronic monitoring of compliance provides important longitudinal information about drug-intake behaviour that cannot be obtained in the clinic. Such monitoring can improve both compliance and blood pressure control, and help physicians to make more rational therapeutic decisions. A reliable assessment of compliance could have a great impact on medical costs by preventing unnecessary investigations or dose adaptations in patients who are not taking their drugs adequately, or potentially reducing the number of hospitalizations. Side-effects and lack of effectiveness are two frequent causes of poor compliance. The right choice of antihypertensive drug can therefore contribute to compliance. In this respect, it is important to find a drug regimen that is effective, long-acting and well tolerated. Long-acting antihypertensive drugs that provide good blood pressure control beyond the 24-h dosing period should perhaps be considered as drugs of choice in non-compliant patients with hypertension because they help to prevent the consequences of occasional drug omissions.
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The use of social media as a communication tool is rapidly growing in the community, and more specifically in patients, through illness blogs. This has been true for several years in North America, but is becoming a reality in Europe as well. We report here the first results of studies on the putative psychological benefits and risks of illness blogs for their authors. We also explore the possible impact of blogging on the patient-caregiver relationship. Social media are expected to have a growing influence in certain areas of health care. Physicians should therefore stay informed about them, take advantage of their benefits, and anticipate their risks.
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The populations of parasites and infectious agents are most of the time structured in complex hierarchy that lies beyond the classical nested design described by Wright's F-statistics (F(IS), F(ST) and F(IT)). In this note we propose a user-friendly step-by-step notice for using recent software (HierFstat) that computes and test fixation indices for any hierarchical structure. We add some tricks and tips for some special data kind (haploid, single locus), some other procedure (bootstrap over loci) and how to handle crossed factors.
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A new radiolarian order - Archaeospicularia - is proposed for some Lower Paleozoic radiolarians previously considered to belong to Spumellaria and to Collodaria. It is characterized by a globular shell made of several spicules which can be free, interlocked, or fused to formed a latticed wall. The present paper gives the definition of this order and proposes a first classification. It is supposed that the Archaeospicularia represents the oldest radiolarian group and that in the Lower Paleozoic it gave rise to the orders Entactinaria, Albaillellaria, and probably Spumellaria by the reduction of the number of initial spicules. The origin of this order and its relationships with other groups of organisms with siliceous skeletons are also briefly discussed. (C) 2000 Academie des sciences / Editions scientifiques et medicales Elsevier SAS.