As transformações de fase em cristais de cianeto de potássio (KCN) a 168&#176K e 83&#176K e suas ligas com KC1, foram estudadas através da absorção ótica no infravermelho do íon de impureza OCN&#8254 e dos íons CN&#8254 da rede. Por aplicação de tensão uniaxial foram obtidos pela primeira vez cristais únicos, da KCN-KCl, nas duas fases de mais baixa temperatura. A absorção ótica dicróica devida à vibração interna do íon CN&#8254 nesses monocristais, permitiu a determinação de seu arranjo estrutural direcional, de forma inequívoca, como também correções a modelo recentemente proposto para esse arranjamento, baseado em experiências com cristais de muitos domínios. O estudo do modo de flexão da impureza OCN&#8254 permitiu o seguimento das transformações de fase anteriormente observadas por meio de medidas de calor específico em cristais puros de KCN. A evolução dessas transformações em função da concentração do íon esférico de Cl&#8254 em substituição do íon elipsoidal CN&#8254 foi estudada numa larga faixa de concentrações. Um modelo para a fase de mais baixa temperatura e proposto com arranjo antiferroelétrico dos dipolos CN&#8254 e com distinção na sub-rede dos íons positivos. Em vista do modelo proposto, duas alternativas para as duas transições de fase poderiam ocorrer. Na transição de mais alta temperatura (168&#176K), ocorreria o alinhamento ferroelástico e antiferroelétrico, dos dipolos CN&#8254, e a transição de mais baixa temperatura (83&#176K) corresponderia somente à distorção na sub-rede dos íons positivos (e possivelmente dos negativos). Na outra possibilidade, a 168&#176K ocorreria somente um arranjo ferroelástico e a 83&#176K o arranjo antiferroelétrico e a distorção na rede. / The phase transformations in potassium cyanide crystals (KCN) at 168&#176K and 83&#176K and KCN-KCl mixed crystals, were studied through the I-r optical absorption of the CN&#8254 stretching mode and the OCN&#8254 impurity bending mode and Fermi resonance application of uniaxial stress in KCN-KCl mixed crystals gives, by the first time, oriented single crystals in the lower temperature phases. The dichroic optical absorption of the CN&#8254 stretching mode in these oriented single crystals allowed the explicit determination of the structural arrangement of the C\'N POT.-\' dipole. The results of our measurements are not in agreement recently proposed by Julian and Luty based on electrical experiments with polidomain crystals. The bending mode and Fermi resonances of the substitutional OC\'N POT.\'impurity give further information in agreement with previous specif heat measurements. The evolution of the phase transformation was studied as a function of the spheroidal Cl&#8254 íon concentration replacing the CN&#8254 ellipsoidal íon. A model for the lower temperature phase is proposed with antiferroelectric ordering of the CN&#8254 dipoles and additional distortion on positive and negative sub lattices. As a consequence of the proposed model the phase transitions, may occur in two different ways that can not be distinguished with the used techniques. In the first possibility during the higher temperature phase transition (168&#176K) would occur the ferroelastic and antiferroelectric alignement of the CN&#8254 dipoles and the lower phase transition (83&#176K) would be due to a lattice distortion as necessary to explain our results. In the other possibility the 168&#176K phase transition would occur only the ferroelastic transition;and at 83&#176K the antiferroelectric ordering of the CN&#8254 ions and the lattice distortion would occur

by Lo Wai Hung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / by Lo Wai Hung. / Acknowledgements --- p.1 / Abstract / 論文摘要 --- p.ii / Table of Contents --- p.iv / List of Figures --- p.vi / List of Tables --- p.viii / Chapter Chapter 1. --- Introduction / Chapter 1.1. --- Magnetoresistance --- p.1 -1 / Chapter 1.1.1. --- Giant magnetoresistance (GMR) --- p.1 -2 / Chapter 1.1.2. --- Colossal Magnetoresistace (CMR) --- p.1 -2 / Chapter 1.2. --- Doping effects in La1-xCaxMn03 --- p.1-4 / Chapter 1.3. --- Metal-Insulator transition in CMR materials --- p.1 -8 / Chapter 1.3.1. --- The sharpness in Metal-Insulator transition --- p.1 -9 / Chapter 1.3.2. --- Possible model to explain CMR in rare-earth manganites --- p.1-12 / Chapter 1.4. --- Low field magnetoresistance --- p.1-14 / Chapter 1.4.1.1. --- Single crystal and polycrystalline perovskite manganites --- p.1-14 / Chapter 1.4.1.2. --- Manganite trilayer junctions --- p.1-15 / Chapter 1.4.2. --- Possible mechanism of low field MR --- p.1-16 / Chapter 1.5. --- Our motivation --- p.1-17 / Chapter 1.5.1. --- Brief review of several manganite superlattices systems --- p.1-18 / Chapter 1.5.2. --- Scope of this thesis work --- p.1-20 / References --- p.1-21 / Chapter Chapter 2. --- Epitaxial growth of LCMO thin films / Chapter 2.1. --- Deposition techniques --- p.2-1 / Chapter 2.1.1. --- Induction --- p.2-1 / Chapter 2.1.2. --- Facing-target sputtering (FTS) --- p.2-1 / Chapter 2.1.3. --- Vacuum system --- p.2-3 / Chapter 2.2. --- Fabrication and characterization of LCMO and PCMO targets --- p.2-4 / Chapter 2.3. --- Epitaxial growth of LCMO thin films --- p.2-9 / Chapter 2.3.1. --- Substrate materials --- p.2-9 / Chapter 2.3.2 --- Deposition --- p.2-10 / Chapter 2.3.2.1. --- Sample preparation --- p.2-10 / Chapter 2.3.2.2. --- Deposition procedure --- p.2-10 / Chapter 2.3.2.3. --- Inter-target distance --- p.2-11 / Chapter 2.3.2.4. --- Deposition Rate --- p.2-15 / Chapter 2.4. --- Substrate temperature effect --- p.2-17 / Chapter 2.4.1. --- Crystal Structure --- p.2-17 / Chapter 2.4.2. --- Transport properties --- p.2-20 / Chapter 2.4.2.1. --- Sharpness of M-I transport properties --- p.2-24 / Chapter 2.4.2.2. --- Magnetoresistance of LCMO/NGO films --- p.2-27 / Chapter 2.5. --- Thickness of LCMO thin film --- p.2-28 / Chapter 2.5.1. --- Crystal Structure --- p.2-29 / Chapter 2.5.2. --- M-I transition properties --- p.2-31 / Chapter 2.5.2.1. --- Sharpness of M-I transport properties --- p.2-35 / Chapter 2.5.2.2. --- Magnetoresistance of LCMO/NGO films --- p.2-36 / Chapter 2.5.2.3. --- Surface Morphology --- p.2-38 / Chapter 2.6. --- Epitaxial growth of PCMO thin films --- p.2-40 / Chapter 2.7. --- Conclusion --- p.2-42 / References --- p.2-43 / Chapter Chapter 3. --- LCMO/PCMO superlattices --- p.3-1 / Chapter 3.1. --- Variation of the PCMO thickness in LCMO/PCMO superlattices --- p.3-2 / Chapter 3.1.1. --- Sample Preparation --- p.3-2 / Chapter 3.1.2. --- Structure characterization by XRD --- p.3-3 / Chapter 3.1.3. --- Transport properties --- p.3-10 / Chapter 3.1.3.1. --- Sharpness of M-I transport properties --- p.3-14 / Chapter 3.1.3.2. --- Magnetoresistance of LCMO/PCMO superlattices --- p.3-16 / Chapter 3.2. --- Variation of the number of LCMO/PCMO bilayer --- p.3-19 / Chapter 3.2.1. --- Sample Preparation --- p.3-19 / Chapter 3.2.2. --- Structure characterization by XRD --- p.3-21 / Chapter 3.2.3. --- Transport properties --- p.3-23 / Chapter 3.2.3.1. --- Sharpness of M-I transport properties --- p.3-27 / Chapter 3.2.3.2. --- Magnetoresistance of LCMO/PCMO superlattices --- p.3-28 / Chapter 3.3. --- Fine adjusting the thickness of PCMO around 10Ain LCMO/PCMO superlattices / Chapter 3.3.1. --- Sample Preparation --- p.3-31 / Chapter 3.3.2. --- Characterization ofLCMO/PCMO superlattices by XRD --- p.3-32 / Chapter 3.3.3. --- Transport properties --- p.3-35 / Chapter 3.3.3.1. --- Sharpness of M-I transport properties --- p.3-39 / Chapter 3.3.3.2. --- Magnetoresistance of LCMO/PCMO superlattices --- p.3-41 / Chapter 3.4. --- Conclusion --- p.3-43 / References --- p.3-44 / Chapter Chapter 4. --- Low-field magnetoresistance (LFMR) / Chapter 4.1. --- Low-field magnetoresistance --- p.4-1 / Chapter 4.2. --- Conclusion --- p.4-5 / References --- p.4-6 / Chapter Chapter 5. --- Structure characterization of LCMO/PCMO superlatticess by crater edge profiling --- p.5-1 / Chapter 5.1. --- Sample preparation --- p.5-2 / Chapter 5.2. --- Structure Characterization --- p.5-2 / Chapter 5.2.1. --- X-ray diffraction (XRD) --- p.5-2 / Chapter 5.2.2. --- The crater edge profiling --- p.5-5 / Chapter 5.2.2.1. --- SEM --- p.5-5 / Chapter 5.2.2.2. --- AES line scan --- p.5-10 / Chapter 5.3. --- Crater edge profiling of P1OO/STO --- p.5-12 / Chapter 5.4. --- Conclusion --- p.5-15 / References --- p.5-16 / Chapter Chapter 6. --- Conclusion --- p.6-1

"The temperature dependence of the contact angle of water on graphite, silicon and gold was investigated under various conditions to test the Sharp-Kink Approximation. Despite correctly predicting the contact angle at room temperature, the ideal Sharp-Kink Approximation was not found to accurately describe the contact angle's temperature dependence. The discrepancies from the predicted contact angle were characterized in terms of a correction H(T) to the liquid-solid surface tension. H(T) was found to be linear in temperature and decreasing, and is consistent with electrostatic charge effects."

Fazemos inicialmente uma breve exposição sobre os fundamentos da Termodinâmica Clássica Holotrópica, desenvolvida por N. Bernardes. Esta consiste em formular o problema da Termodinâmica tomando como grandeza fundamental a entropia de um universo ( - sistema Isolado); no caso de um universo clássico composto esta é igual a soma das entropias de suas partes. Postulamos um principio dinâmico suficiente para a validade da segunda lei da Termodinâmica, o qual implica que os máximos dessa soma são estados estacionários estáveis do universo. Somos levados naturalmente a perguntar o que acontece se a entropia do universo possuir mais do que um máximo; a resposta a isso é o tratamento que daremos ao fenômeno de transição de fase. Analisamos em detalhe o universo composto por um corpo pequeno (cuja entropia é por hipótese analítica) e reservatórios de calor e trabalho. Para que a entropia do universo possua mais que um máximo a entropia do corpo pequeno não pode ser côncava em todo seu domínio; assumindo uma forma particular para ela (deslocamento de Bernardes) analisaremos o equilíbrio entre duas fases e o comportamento em torno do ponto onde a curva de coexistência termina (ponto crítico isolado). Com isto será possível dar uma visão clara e bastante intuitiva do fenômeno de transição de fase dito \"de primeira ordem\". Tendo em mente o significado físico das transformadas de Legendre da entropia do corpo pequeno (transparente na formulação holotrópica) compreenderemos o sentido das descontinuidades de primeira e segunda ordem que afetam as funções termodinâmicas que descrevem o equilíbrio do universo, com o que não veremos razão alguma para classificar as transições de fase da maneira que assim fez Ehrenfest. Veremos também, e isto é muito importante, que a Termodinâmica Clássica não consegue explicar a singularidade no calor específico que se verifica experimentalmente num ponto crítico, sendo que esta falha é intrínseca ou à Termodinâmica clássica ou à hipótese da entropia do corpo pequeno ser contínua e diferenciável. / We make initially a short exposition about the fundaments of Holotropic classical thermodynamics, developed by N. Bernardes. This is the formulation of the thermodynamic problem taking the entropy of a universe (isolated system) as the fundamental variable. In a classical composite universe it is the sum of the entropies of its parts. We postulate a dynamic principle sufficient for the validity of the second law of Thermodynamics, which implies that the maxima of that sum are stable stationary states of the universe. We arrive at the question about what occurs when the entropy of the universe possesses more than one maximum; the answer is the treatment we will give to the phenomena of phase transition. We analyze in detail the universe composed by a small body (whose entropy is analytical by hypothesis) and heat and work reservoirs. The entropy of the small body must be not concave in all of its dominium for the entropy of universe to have more than one maximum; we make a particular choice for it (Bernardes displacement) in order to analyze equilibrium between two phases and the behavior around the point where the coexistence curve terminates (isolated critical point). With this it will be possible to have a clear and intuitive grasp of the phenomena called \"first order\" phase transition. Keeping in mind the physical meaning of the Legendre transforms of the entropy of the small body we will understand the meaning of the first and second order discontinuities that affect the thermodynamic functions which describe the equilibrium state of the universe. We will see no reason to classify phase transitions the way Ehrenfest did. We will see also, and this is a very important thing, that classical Thermodynamics cannot explain the singularity that occurs in specific heat at a critical point. This failure is intrinsic to classical Thermodynamics or to the hypothesis that the small body entropy is a continuous and differentiable function.

Objetivos: Avaliar os correlatos sociodemográficos associados com as transições entre os estágios de uso do álcool (desde o primeiro uso na vida até o desenvolvimento de transtornos relacionados ao uso, como abuso e dependência, AUD) e remissão, em uma amostra da população geral residente na Região Metropolitana de São Paulo (RMSP), com 18 anos de idade ou mais. Métodos: Uma amostra probabilística e multiestratificada de adultos domiciliados (n = 5.037) na RMSP foi estudada. O uso de álcool, uso regular (pelo menos 12 doses/ ano), abuso e dependência de acordo com os critérios do DSM-IV, e remissão de AUD foram avaliados utilizando-se a versão do Composite International Diagnostic Interview para o World Mental Health Survey. As curvas de idade de início cumulativas (AOO) para o primeiro uso de álcool na vida, o uso regular, o abuso e a dependência foram elaboradas com dados obtidos a partir da amostra de 5.037 indivíduos. Os correlatos sociodemográficos das transições entre os estágios de uso do álcool e da remissão de AUD foram obtidos a partir de uma subamostra de 2.942 entrevistados, para os quais, os dados sociodemográficos tempodependentes estavam disponíveis. Resultados: as prevalências encontradas foram: 85,8% de uso de álcool na vida, 56,2% de uso regular, 10,6% de abuso e 3,6% de dependência. As probabilidades de transição foram: 63,1% do primeiro uso na vida para o uso regular, 17,9% do uso regular para o abuso, e 28,3% do abuso para dependência. Remitiram 73,4% e 58,8% dos entrevistados com diagnóstico de abuso e dependência de álcool na vida, respectivamente. Todas as transições entre os estágios de uso de álcool até o abuso estiveram consistentemente associadas ao sexo masculino, às gerações mais jovens e à baixa escolaridade, sendo que outros correlatos variaram entre as transições. Vale a pena destacar que baixa escolaridade foi um correlato para o desenvolvimento de abuso e dependência e para a não remissão destes transtornos. Idade de início precoce do uso regular esteve associada com a transição para o abuso de álcool entre usuários regulares. Conclusões: O presente estudo demonstra que correlatos específicos contribuem diferentemente no decorrer da trajetória de uso de álcool nesta amostra populacional de São Paulo. Nossos achados reforçam a necessidade de programas para prevenir a iniciação precoce do uso de álcool e que os esforços devem estar concentrados nos indivíduos de menor nível socioeconômico e de baixa escolaridade, a fim de minimizar a progressão para AUD e melhorar a remissão dessas condições. Além disto, a partir deste estudo, sugerimos a inclusão da idade de início no modelo do Índice de Risco Comparativo (Comparative Risk Assessment - CRA) utilizado pelo estudo Global Burden of Diseases para estimar as conseqüências negativas decorrentes do uso do álcool no Brasil e no mundo / Aims: To evaluate socio-demographic correlates associated with transitions across alcohol use stages (from first use to alcohol use disorders, AUD) and remission in a sample of household residents in the São Paulo Metropolitan Area adult, aged 18 years and over. Methods: A probabilistic, multi-stage clustered sample of adult household residents (n=5,037) in the São Paulo Metropolitan Area was analyzed. Alcohol use, regular use (at least 12 drinks/year), DSM-IV abuse and dependence, and remission from AUD were assessed with the World Mental Health version of the Composite International Diagnostic Interview. Age of onset (AOO) distributions of the cumulative lifetime probability of alcohol use, regular use, abuse, and dependence were prepared with data obtained from 5,037 subjects. Correlates of transition across alcohol use stages and remission were obtained from a subsample of 2,942 respondents, whose time-dependent sociodemographic data were available. Results: Lifetime prevalences were 85.8% for alcohol use, 56.2% for regular use, 10.6% for abuse, and 3.6% for dependence. The transitions probabilities were 63.1% for everuse to regular use, 17.9% for regular use to abuse, and 28.3% for abuse to dependence; 73.4% and 58.8% of respondents with lifetime abuse and dependence, respectively, had remitted. All transitions across alcohol use stages up to abuse were consistently associated with male gender, younger cohorts and low education, with other correlates varying among transitions. Importantly, low education was a correlate for developing AUD and for not remitting from them. Early AOO of regular use was associated with alcohol abuse among regular users. Conclusions: The present study demonstrates that specific correlates differently contribute throughout alcohol use trajectory in a Brazilian population. Our findings reinforce the need of programs to prevent early initiation of alcohol use and that efforts should focus on individuals of lower socioeconomical levels and low education, in order to minimize the progression to AUD and improve remission from these conditions. Moreover, based on these findings we suggest the inclusion of age of onset in the conceptual model used for the current analysis of alcohol within the Global Burden of Disease and Injury study

<p>Protein conformational transitions are fundamental to the functions of many proteins, and computational methods are valuable for elucidating the transitions that are not readily accessible by experimental techniques. Here we developed accelerated sampling methods to calculate optimized all-atom protein conformational transition paths. Adaptively biased path optimization (ABPO) is a computational simulation method to optimize the conformational transition path between two states. We first examined the transition paths of three systems with relatively simple transitions. The ways to define reduced variables were explored and transition paths were built at convergence of the optimizations. We constructed the all-atom conformational transition path between the active and the inactive states of the Src kinase domain. The C helix rotation was identified as the main free energy barrier in the all‑atom system, and the intermediate conformations and key interactions along the transition path were analyzed. This is the first demonstration of the robustness of a computational method for calculating protein conformational transitions without restraints to a specified path. We also evaluated protein‑peptide interactions using both molecular dynamics simulations and peptide docking. Long unbiased simulations were used to evaluate Src‑SSP interactions and complex stability in both implicit and explicit solvent. Molecular docking was used to build possible protein‑peptide interaction models, using both Src regulatory domain SH2 and the kinase domain. Possible Src‑SSP complexes were built as the first Src‑substrate complex structure models.</p>

This dissertation focuses on how perceptions of ethnicity and culture become meaningful in relation to the transition from care into independent living, studied from unaccompanied youths’, professionals’, and a methodological perspective. The findings from interviews with unaccompanied youth with experience of leaving care showed that thoughts about their ethnic minority background are constantly present in the young men’s lives. Their stories about preparing to leave care show a continuous attempt to make adjustments in order to fit into the Swedish society (Study I). The results based on interviews with professionals and observations at two residential care units indicated that ‘home’ is sometimes used as a metaphor when describing the residential care units. The home metaphor affected the staff in ways that it sometimes became difficult to separate private and professional matters. The clash between the residential care unit and the desire to create a home environment highlights the issue that programs executed in Sweden for unaccompanied young people were originally not made for them (Study II). Study III emphasised how transnational relationships form the unaccompanied youths view of past, present, and future time. This study highlighted the importance of how the professionals need to understand the unaccompanied children and youth and their situation as flexible (Study III). Finally, methodological reflections about research concerning ethnicity indicated the importance of reflecting on one’s own perceptions, the role as a researcher, and the benefits and limitations these different roles may have in the research process (Study IV). The research was conducted using qualitative methods. The data collection methods entailed interviews with the youth (Study I), individual interviews, focus-groups, and observations with professionals (Study II and III), and discussions based on the data collected for study I-III (Study IV). Altogether, 11 youths (18-22 years) and about 20 professionals at the residential care units participated in the studies. Qualitative content analysis was used to analyse the individual interviews and the focus-groups. All interviews were transcribed verbatim for analysis. The empirical data from observations consisted of notes taken during everyday situations, as well as from short conversations with the professionals. The notes were analysed using qualitative content analysis. The combined results of study I-III were used as empirical data for the analysis in study IV. This dissertation shows that (re)constructing a home is a central part of the care-leaving process for a migrant about to resettle in a new country. The greatest challenge the unaccompanied youth have to conquer during the transition from care to independent living is to fight against exclusion. The main purpose in (re)constructing a home appears to be the same for the youth and the professionals, namely, to reach a sense of safety and belonging. However, different conditions and points of departure may make it hard to agree on details such as what the meaning of belonging actually is, and if it is possible to develop a tailor-made solution. Researching issues of ethnicity comes with the responsibility to avoid reinforcing an ‘us’ versus ‘them’ and, in so doing, reinforce stereotypes.

This dissertation is dedicated to the rigorous study of discontinuous transitions in star graphs of coupled phase oscillators. A star graph consists of a central node, called hub, connected to peripheral nodes called leaves. We consider the setting where the frequency of the leaves is identical and the hub has a higher frequency when isolated. This captures the effect of positive correlation between the hub high number of connections and its high natural frequency. Hub higher frequency turns out to be the key feature for discontinuity in the transition from incoherent to synchronous behavior. This transition has been observed numerically and explained via a non-rigorous analytical treatment in the thermodynamic limit. Using Möbius group reduction and the theory of persistence of normally hyperbolic invariant manifold, we prove that this transition is indeed discontinuous for a certain set of initial conditions. / Esta dissertação dedica-se em estudar rigorosamente transições descontínuas de osciladores de fase acoplados em grafos estrelas. Um grafo estrela é composto de um nó central, chamado hub, conectado a nós periféricos chamados folhas. Consideramos a situação na qual a frequência das folhas é igual e o hub tem frequência mais elevada, o efeito de correlação positiva entre o grande número de conexões do hub e sua frequência. A elevada frequência do hub resulta por ser o aspecto crucial na descontinuidade da transição do comportamento incoerente para o síncrono. Esta transição foi observada numericamente e estudada por meio de tratamento analítico não rigoroso no limite termodinâmico. Usando técnica de redução a partir do grupo de Möbius e a teoria de variedades invariantes normalmente hiperbólicias, provamos que esta transição é de fato descontínua para certo conjunto de condições iniciais.

Fazemos inicialmente uma breve exposição sobre os fundamentos da Termodinâmica Clássica Holotrópica, desenvolvida por N. Bernardes. Esta consiste em formular o problema da Termodinâmica tomando como grandeza fundamental a entropia de um universo ( - sistema Isolado); no caso de um universo clássico composto esta é igual a soma das entropias de suas partes. Postulamos um principio dinâmico suficiente para a validade da segunda lei da Termodinâmica, o qual implica que os máximos dessa soma são estados estacionários estáveis do universo. Somos levados naturalmente a perguntar o que acontece se a entropia do universo possuir mais do que um máximo; a resposta a isso é o tratamento que daremos ao fenômeno de transição de fase. Analisamos em detalhe o universo composto por um corpo pequeno (cuja entropia é por hipótese analítica) e reservatórios de calor e trabalho. Para que a entropia do universo possua mais que um máximo a entropia do corpo pequeno não pode ser côncava em todo seu domínio; assumindo uma forma particular para ela (deslocamento de Bernardes) analisaremos o equilíbrio entre duas fases e o comportamento em torno do ponto onde a curva de coexistência termina (ponto crítico isolado). Com isto será possível dar uma visão clara e bastante intuitiva do fenômeno de transição de fase dito \"de primeira ordem\". Tendo em mente o significado físico das transformadas de Legendre da entropia do corpo pequeno (transparente na formulação holotrópica) compreenderemos o sentido das descontinuidades de primeira e segunda ordem que afetam as funções termodinâmicas que descrevem o equilíbrio do universo, com o que não veremos razão alguma para classificar as transições de fase da maneira que assim fez Ehrenfest. Veremos também, e isto é muito importante, que a Termodinâmica Clássica não consegue explicar a singularidade no calor específico que se verifica experimentalmente num ponto crítico, sendo que esta falha é intrínseca ou à Termodinâmica clássica ou à hipótese da entropia do corpo pequeno ser contínua e diferenciável. / We make initially a short exposition about the fundaments of Holotropic classical thermodynamics, developed by N. Bernardes. This is the formulation of the thermodynamic problem taking the entropy of a universe (isolated system) as the fundamental variable. In a classical composite universe it is the sum of the entropies of its parts. We postulate a dynamic principle sufficient for the validity of the second law of Thermodynamics, which implies that the maxima of that sum are stable stationary states of the universe. We arrive at the question about what occurs when the entropy of the universe possesses more than one maximum; the answer is the treatment we will give to the phenomena of phase transition. We analyze in detail the universe composed by a small body (whose entropy is analytical by hypothesis) and heat and work reservoirs. The entropy of the small body must be not concave in all of its dominium for the entropy of universe to have more than one maximum; we make a particular choice for it (Bernardes displacement) in order to analyze equilibrium between two phases and the behavior around the point where the coexistence curve terminates (isolated critical point). With this it will be possible to have a clear and intuitive grasp of the phenomena called \"first order\" phase transition. Keeping in mind the physical meaning of the Legendre transforms of the entropy of the small body we will understand the meaning of the first and second order discontinuities that affect the thermodynamic functions which describe the equilibrium state of the universe. We will see no reason to classify phase transitions the way Ehrenfest did. We will see also, and this is a very important thing, that classical Thermodynamics cannot explain the singularity that occurs in specific heat at a critical point. This failure is intrinsic to classical Thermodynamics or to the hypothesis that the small body entropy is a continuous and differentiable function.

From the author’s work as an educational psychologist in a Scottish local authority and her initial literature review, concerns were raised by her colleagues and local education authority about delaying school entry of children with additional support needs. This study aimed to: explore how the decision making process for delaying school entry operated; develop and trial a methodology to capture the children’s perspective and explore the experiences of the children and their families in nursery and during their first year of school. A qualitative case study approach was used to explore the decision making process for six children and their families and the experiences of five children and their families. Techniques from the mosaic methodology (Clark and Moss, 2001) were adapted to capture the children’s voices. The study revealed that participants held different models of school readiness, in line with other international research, and this influenced their decision to retain. Participants reported a range of positive and negative outcomes of delayed school entry and identified factors that had been supportive in managing the children’s transitions. Children’s perspectives were captured and often offered a unique insight into the children’s views. At the end of the children’s first year in primary school four parents were still happy with their decision to delay school entry but one parent regretted her decision. In conclusion it is suggested that a more interactionist (Meisels, 1998) approach to school readiness should be taken when supporting the transition from nursery to school. A moderated system should be developed to support the decision making process for delaying school entry, with an inbuilt process to follow up longer-term outcomes for the children and families concerned. The methodology developed for gathering children’s views offered a way for children with additional support needs to express their own views and take an active role at this important transition point. There is potential to develop this methodology further to ensure that children’s voices are heard in this first universal educational transition.