780 resultados para Transition to first birth
Resumo:
Law is saturated with stories. People tell their stories to lawyers; lawyers tell their client's stories to courts; and legislators develop regulation to respond to their constituent's stories of injustice or inequality. My approach to first-year legal education respects this narrative tradition. Both my curriculum design and assessment scheme in the compulsory first-year subject Australian Legal System deploy narrative methodology as the central teaching and learning device. Throughout the course, students work on resolving the problems of four hypothetical clients. Like a murder mystery, pieces of the puzzle come together as students learn more about legal institutions and the texts they produce, the process of legal research, the analysis and interpretation of primary legal sources, the steps in legal problem-solving, the genre conventions of legal writing style, the practical skills and ethical dimensions of professional practice, and critical inquiry into the normative underpinnings and impacts of the law. The assessment scheme mirrors this design. In their portfolio-based assignment, for example, students devise their own client profile, research the client's legal position and prepare a memorandum of advice.
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Diploma students transitioning into the NS40 BNursing (BN) course at QUT withdraw from the bioscience and pharmacology units, and leave the university at higher rates than traditional students. The diploma students, entering in second year, have missed out on 2 units of bioscience taught to the traditional students in their first year, and miss out on a 3rd unit of bioscience taught to the traditional students in their 2nd year. Instead the diploma students receive one specialized unit in bioscience only i.e. a bridging unit. As a consequence, the diploma students may not have the depth of bioscience knowledge to be able to successfully study the bridging unit (LSB111) or the pharmacology unit (LSB384). Our plan was to write an eBook which refreshed and reinforced diploma students’ knowledge of bioscience aiming to prepare them with the concepts and terminology, and to build a level of confidence to support their transition to the BN. We have previously developed an intervention associated with reduced attrition of diploma nursing students, and this was our starting point. The study skills part of the initial intervention was addressed in the eBook, by links to the specialist services and resources available from our liaison librarian and academic skills adviser. The introductory bioscience/pharmacology information provided by the previous intervention involved material from standard textbooks. However, we considered this material too difficult for diploma students. Thus, we created simplified diagrams to go with text as part of our eBook. The outcome is an eBook, created and made available to the diploma students via the Community Website: “Surviving Bioscience and Pharmacology”. Using simplified diagrams to illustrate the concise text, definition to explain the concepts, the focus has been on encouraging self-awareness and help-seeking strategies and building students who take responsibility for their learning. All the nursing students in the second semester LSB384 Pharmacology Unit have been surveyed face-to-face to get feedback on their engagement with the eBook resource. The data has not been analysed to date. An important consideration is that the website be evaluated by the diploma students as they come into bioscience in first semester (LSB111), the student population for whom the eBook is primarily intended. To get a good response rate we need to do a face-to-face survey. However, we have not been able to do this, as the co-ordinator of the unit has changed since we started the project, and the present co-ordinator will not allow us access to these students.
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The dielectric measurement of ferroelectric trissarcosine calcium chloride (TSCC) was made under various pressures up to 6 kbar. A striking decrease in the peak value of the permittivity, epsilon r, at the transition temperature, Tc, was observed with increasing pressure. The value of Tc increases linearly with a pressure coefficient dTc/dp=11.1K kbar-1 at low pressures. This increase in Tc supports the suggestion that the ferroelectric transition is of the pure order-disorder type. It is suggested on the basis of the behaviour of epsilon r with pressure that the order of the ferroelectric transition changes from second to first order on application of pressure.
Resumo:
When ordinary nuclear matter is heated to a high temperature of ~ 10^12 K, it undergoes a deconfinement transition to a new phase, strongly interacting quark-gluon plasma. While the color charged fundamental constituents of the nuclei, the quarks and gluons, are at low temperatures permanently confined inside color neutral hadrons, in the plasma the color degrees of freedom become dominant over nuclear, rather than merely nucleonic, volumes. Quantum Chromodynamics (QCD) is the accepted theory of the strong interactions, and confines quarks and gluons inside hadrons. The theory was formulated in early seventies, but deriving first principles predictions from it still remains a challenge, and novel methods of studying it are needed. One such method is dimensional reduction, in which the high temperature dynamics of static observables of the full four-dimensional theory are described using a simpler three-dimensional effective theory, having only the static modes of the various fields as its degrees of freedom. A perturbatively constructed effective theory is known to provide a good description of the plasma at high temperatures, where asymptotic freedom makes the gauge coupling small. In addition to this, numerical lattice simulations have, however, shown that the perturbatively constructed theory gives a surprisingly good description of the plasma all the way down to temperatures a few times the transition temperature. Near the critical temperature, the effective theory, however, ceases to give a valid description of the physics, since it fails to respect the approximate center symmetry of the full theory. The symmetry plays a key role in the dynamics near the phase transition, and thus one expects that the regime of validity of the dimensionally reduced theories can be significantly extended towards the deconfinement transition by incorporating the center symmetry in them. In the introductory part of the thesis, the status of dimensionally reduced effective theories of high temperature QCD is reviewed, placing emphasis on the phase structure of the theories. In the first research paper included in the thesis, the non-perturbative input required in computing the g^6 term in the weak coupling expansion of the pressure of QCD is computed in the effective theory framework at an arbitrary number of colors. The two last papers on the other hand focus on the construction of the center-symmetric effective theories, and subsequently the first non-perturbative studies of these theories are presented. Non-perturbative lattice simulations of a center-symmetric effective theory for SU(2) Yang-Mills theory show --- in sharp contrast to the perturbative setup --- that the effective theory accommodates a phase transition in the correct universality class of the full theory. This transition is seen to take place at a value of the effective theory coupling constant that is consistent with the full theory coupling at the critical temperature.
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A nonequilibrium generalization of the density-functional theory of freezing is proposed to investigate the shear-induced first-order phase transition in colloidal suspensions. It is assumed that the main effect of a steady shear is to break the symmetry of the structure factor of the liquid and that for small shear rate, the phenomenon of a shear-induced order-disorder transition may be viewed as an equilibrium phase transition. The theory predicts that the effective density at which freezing takes place increases with shear rate. The solid (which is assumed to be a bcc lattice) formed upon freezing is distorted and specifically there is less order in one plane compared with the order in the other two perpendicular planes. It is shown that there exists a critical shear rate above which the colloidal liquid does not undergo a transition to an ordered (or partially ordered) state no matter how large the density is. Conversely, above the critical shear rate an initially formed bcc solid always melts into an amorphous or liquidlike state. Several of these predictions are in qualitative agreement with the light-scattering experiments of Ackerson and Clark. The limitations as well as possible extensions of the theory are also discussed.
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A flow-induced instability in a tube with flexible walls is studied experimentally. Tubes of diameter 0.8 and 1.2 mm are cast in polydimethylsiloxane (PDMS) polymer gels, and the catalyst concentration in these gels is varied to obtain shear modulus in the range 17–550 kPa. A pressure drop between the inlet and outlet of the tube is used to drive fluid flow, and the friction factor $f$ is measured as a function of the Reynolds number $Re$. From these measurements, it is found that the laminar flow becomes unstable, and there is a transition to a more complicated flow profile, for Reynolds numbers as low as 500 for the softest gels used here. The nature of the $f$–$Re$ curves is also qualitatively different from that in the flow past rigid tubes; in contrast to the discontinuous increase in the friction factor at transition in a rigid tube, it is found that there is a continuous increase in the friction factor from the laminar value of $16\ensuremath{/} Re$ in a flexible tube. The onset of transition is also detected by a dye-stream method, where a stream of dye is injected into the centre of the tube. It is found that there is a continuous increase of the amplitude of perturbations at the onset of transition in a flexible tube, in contrast to the abrupt disruption of the dye stream at transition in a rigid tube. There are oscillations in the wall of the tube at the onset of transition, which is detected from the laser scattering off the walls of the tube. This indicates that the coupling between the fluid stresses and the elastic stresses in the wall results in an instability of the laminar flow.
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We present a spin model, namely, the Kitaev model augmented by a loop term and perturbed by an Ising Hamiltonian, and show that it exhibits both confinement-deconfinement transitions from spin liquid to antiferromagnetic/spin-chain/ferromagnetic phases and topological quantum phase transitions between gapped and gapless spin-liquid phases. We develop a fermionic resonating-valence-bonds (RVB) mean-field theory to chart out the phase diagram of the model and estimate the stability of its spin-liquid phases, which might be relevant for attempts to realize the model in optical lattices and other spin systems. We present an analytical mean-field theory to study the confinement-deconfinement transition for large coefficient of the loop term and show that this transition is first order within such mean-field analysis in this limit. We also conjecture that in some other regimes, the confinement-deconfinement transitions in the model, predicted to be first order within the mean-field theory, may become second order via a defect condensation mechanism. Finally, we present a general classification of the perturbations to the Kitaev model on the basis of their effect on it's spin correlation functions and derive a necessary and sufficient condition, within the regime of validity of perturbation theory, for the spin correlators to exhibit a long-ranged power-law behavior in the presence of such perturbations. Our results reproduce those of Tikhonov et al. [Phys. Rev. Lett. 106, 067203 (2011)] as a special case.
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Our in situ x-ray diffraction and Raman measurements of Yb2Ti2O7 pyrochlore show that it undergoes a reversible structural phase transition from cubic pyrochlore to a monoclinic phase at similar to 28.6 GPa. Analysis of the x-ray data shows the transition to be thermodynamically first order and the high pressure phase to be substitutionally disordered. These experimental results are supported by our first principles calculations. (C) 2012 American Institute of Physics. [doi:10.1063/1.3681300]
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The interaction between the digital human model (DHM) and environment typically occurs in two distinct modes; one, when the DHM maintains contacts with the environment using its self weight, wherein associated reaction forces at the interface due to gravity are unidirectional; two, when the DHM applies both tension and compression on the environment through anchoring. For static balancing in first mode of interaction, it is sufficient to maintain the projection of the centre of mass (COM) inside the convex region induced by the weight supporting segments of the body on a horizontal plane. In DHM, static balancing is required while performing specified tasks such as reach, manipulation and locomotion; otherwise the simulations would not be realistic. This paper establishes the geometric relationships that must be satisfied for maintaining static balance while altering the support configurations for a given posture and altering the posture for a given support condition. For a given location of the COM for a system supported by multiple point contacts, the conditions for simultaneous withdrawal of a specified set of contacts have been determined in terms of the convex hulls of the subsets of the points of contact. When the projection of COM must move beyond the existing support for performing some task, new supports must be enabled for maintaining static balance. This support seeking behavior could also manifest while planning for reduction of support stresses. Feasibility of such a support depends upon the availability of necessary features in the environment. Geometric conditions necessary for selection of new support on horizontal,inclined and vertical surfaces within the workspace of the DHM for such dynamic scenario have been derived. The concepts developed are demonstrated using the cases of sit-to-stand posture transition for manipulation of COM within the convex supporting polygon, and statically stable walking gaits for support seeking within the kinematic capabilities of the DHM. The theory developed helps in making the DHM realize appropriate behaviors in diverse scenarios autonomously.
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This paper reports first observations of transition in recirculation pattern from an open-bubble type axisymmetric vortex breakdown to partially open bubble mode through an intermediate, critical regime of conical sheet formation in an unconfined, co-axial isothermal swirling flow. This time-mean transition is studied for two distinct flow modes which are characterized based on the modified Rossby number (Ro(m)), i.e., Ro(m) <= 1 and Ro(m) > 1. Flow modes with Ro(m) <= 1 are observed to first undergo cone-type breakdown and then to partially open bubble state as the geometric swirl number (S-G) is increased by similar to 20% and similar to 40%, respectively, from the baseline open-bubble state. However, the flow modes with Ro(m) > 1 fail to undergo such sequential transition. This distinct behavior is explained based on the physical significance associated with Ro(m) and the swirl momentum factor (xi). In essence, xi represents the ratio of angular momentum distributed across the flow structure to that distributed from central axis to the edge of the vortex core. It is observed that xi increases by similar to 100% in the critical swirl number band where conical breakdown occurs as compared to its magnitude in the S-G regime where open bubble state is seen. This results from the fact that flow modes with Ro(m) <= 1 are dominated by radial pressure gradient due to swirl/rotational effect when compared to radial pressure deficit arising from entrainment (due to the presence of co-stream). Consequently, the imparted swirl tends to penetrate easily towards the central axis causing it to spread laterally and finally undergo conical sheet breakdown. However, the flow modes with Ro(m) > 1 are dominated by pressure deficit due to entrainment effect. This blocks the radial inward penetration of imparted angular momentum thus preventing the lateral spread of these flow modes. As such these structures fail to undergo cone mode of vortex breakdown which is substantiated by a mere 30%-40% rise in xi in the critical swirl number range. (C) 2014 AIP Publishing LLC.
Resumo:
Este estudo, de natureza histórico-social, tem como objeto a criação da Associação Brasileira de Obstetrizes e Enfermeiros Obstetras (ABENFO) e suas estratégias no Movimento de Humanização do Parto e Nascimento Brasileiro (1989-2002). A delimitação temporal do estudo abrange o período de 1989 a 2002. Os objetivos da pesquisa são: analisar a transição da Associação Brasileira de Obstetrizes (ABO) para Associação Brasileira de Obstetrizes e Enfermeiros Obstetras (ABENFO); analisar as estratégias elaboradas pela ABENFO para a atualização do habitus das agentes; analisar o fortalecimento do Movimento de Humanização do Parto e Nascimento empreendido pela ABENFO. O estudo apoia-se teoricamente nos conceitos desenvolvidos pelo sociólogo Pierre Bourdieu e utilizou o método da história oral temática. Na análise, houve a articulação de documentos escritos e depoimentos orais à luz do referencial teórico. Os resultados da pesquisa evidenciam que, no processo de surgimento da ABENFO, houve um período de aproximações de agentes que durou aproximadamente 15 anos. A primeira aproximação foi entre parteiras/obstetrizes e as enfermeiras no campo sindical; a segunda aproximação de agentes, desta vez pelo habitus profissional, foi de enfermeiras de saúde pública e enfermeiras obstétricas no campo hospitalar e científico; e a terceira aproximação foi entre as parteiras/obstetrizes com as enfermeiras obstétricas. Após essas aproximações, a enfermeira obstétrica assumiu a diretoria provisória da ABO, realizando, em seguida, a transição para a ABENFO. Após a transição, a ABENFO nacional consolidou-se como representante das enfermeiras obstétricas e obstetrizes. Em seguida, foi necessário criar estratégias para atualizar o habitus das agentes, tais como: Estratégias de fortalecimento da Associação no campo político da Enfermagem e da Saúde da Mulher; Estratégias de ampliação da sua representação nacional entre enfermeiras obstétricas; Estratégias para divulgação do capital social da ABENFO. Dentre as estratégias de divulgação, aconteceram três Congressos Brasileiros de Enfermagem Obstétrica e Neonatal (COBEONS) que fortaleceram o Movimento de Humanização do Parto e Nascimento, pois neste espaço circulou o capital sociocultural do movimento social entre as associadas, levando aos mesmos uma atualização do seu habitus, e, por outro lado, fortalecendo o Movimento por meio do reconhecimento. Portanto, o fortalecimento do processo de humanização do parto e nascimento brasileiro confirmou a hipótese de que a criação da ABENFO possibilitou a elaboração de estratégias que impulsionaram a atualização do habitus das agentes. Este estudo foi esclarecedor, na medida em que favoreceu a compreensão das circunstâncias de criação da ABENFO e sua participação como a única representante das enfermeiras obstétricas e obstetrizes no Movimento de Humanização do Parto e Nascimento, além de demonstrar o quanto estas agentes contribuíram para a sua consolidação.
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The majority of computational studies of confined explosion hazards apply simple and inaccurate combustion models, requiring ad hoc corrections to obtain realistic flame shapes and often predicting an order of magnitude error in the overpressures. This work describes the application of a laminar flamelet model to a series of two-dimensional test cases. The model is computationally efficient applying an algebraic expression to calculate the flame surface area, an empirical correlation for the laminar flame speed and a novel unstructured, solution adaptive numerical grid system which allows important features of the solution to be resolved close to the flame. Accurate flame shapes are predicted, the correct burning rate is predicted near the walls, and an improvement in the predicted overpressures is obtained. However, in these fully turbulent calculations the overpressures are still too high and the flame arrival times too low, indicating the need for a model for the early laminar burning phase. Due to the computational expense, it is unrealistic to model a laminar flame in the complex geometries involved and therefore a pragmatic approach is employed which constrains the flame to propagate at the laminar flame speed. Transition to turbulent burning occurs at a specified turbulent Reynolds number. With the laminar phase model included, the predicted flame arrival times increase significantly, but are still too low. However, this has no significant effect on the overpressures, which are predicted accurately for a baffled channel test case where rapid transition occurs once the flame reaches the first pair of baffles. In a channel with obstacles on the centreline, transition is more gradual and the accuracy of the predicted overpressures is reduced. However, although the accuracy is still less than desirable in some cases, it is much better than the order of magnitude error previously expected.
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A laboratory scale desktop test system including a cryogenic system, an AC pulse generation system and a real time data acquisition program in LabView/DAQmx, has been developed to evaluate the quench properties of MgB 2 wires as an element in a superconducting fault current limiter under pulse overcurrents at 25K in self-field conditions. The MgB2 samples started from a superconducting state and demonstrated good current limiting properties characterized by a fast transition to the normal state during the first half of the cycle and a continuously limiting effect in the subsequent cycles without burnouts. The experimental and numerical simulation results on the quench behaviour indicate the feasibility of using MgB 2 for future superconducting fault current limiter (SFCL) applications. © IOP Publishing Ltd.
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Screech is a high frequency oscillation that is usually characterized by instabilities caused by large-scale coherent flow structures in the wake of bluff-body flameholders and shear layers. Such oscillations can lead to changes in flame surface area which can cause the flame to burn unsteadily, but also couple with the acoustic modes and inherent fluid-mechanical instabilities that are present in the system. In this study, the flame response to hydrodynamic oscillations is analyzed in a controlled manner using high-fidelity Computational Fluid Dynamics (CFD) with an unsteady Reynolds-averaged Navier-Stokes approach. The response of a premixed flame with and without transverse velocity forcing is analyzed. When unforced, the flame is shown to exhibit a self-excitation that is attributed to the anti-symmetric shedding of vortices in the wake of the flameholder. The flame is also forced using two different kinds of low-amplitude out-of-phase inlet velocity forcing signals. The first forcing method is harmonic forcing with a single characteristic frequency, while the second forcing method involves a broadband forcing signal with frequencies in the range of 500 - 1000 Hz. For the harmonic forcing method, the flame is perturbed only lightly about its mean position and exhibits a limit cycle oscillation that is characteristic of the forcing frequency. For the broadband forcing method, larger changes in the flame surface area and detachment of the flame sheet can be seen. Transition to a complicated trajectory in the phase space is observed. When analyzed systematically with system identification methods, the CFD results, expressed in the form of the Flame Transfer Function (FTF) are capable of elucidating the flame response to the imposed perturbation. The FTF also serves to identify, both spatially and temporally, regions where the flame responds linearly and nonlinearly. Locking-in between the flame's natural self-excited frequency and the subharmonic frequencies of the broadband forcing signal is found to alter the dynamical behaviour of the flame. Copyright © 2013 by ASME.
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The phase transition of two kinds of solvent-induced crystalline syndiotactic polystyrene (sPS). gamma-sPS and delta(c)-sPS, has been studied via WAXD and DSC. gamma-sPS transform to a-sPS at 195-225 degrees C before melt during heating, whereas delta(e)-sPS transform to first gamma-sPS and then a-sPS at 100-200 degrees C and 200-215 degrees C, respectively. The transition of delta(e)-gamma and gamma-a occurs for below melting point of sPS indicates they are all solid-solid transition.