Investigations on The Finite Size Effects of Some Inverse Spinels and Studies on Their Composites Based on Nitrile Rubber

Magnetism and magnetic materials have been an ever-attractive subject area for engineers and scientists alike because of its versatility in finding applications in useful devices. They find applications in a host of devices ranging from rudimentary devices like loud speakers to sophisticated gadgets like waveguides and Magnetic Random Access Memories (MRAM).The one and only material in the realm of magnetism that has been at the centre stage of applications is ferrites and in that spinel ferrites received the lions share as far as practical applications are concerned.It has been the endeavour of scientists and engineers to remove obsolescence and improve upon the existing so as to save energy and integrate in to various other systems. This has been the hallmark of material scientists and this has led to new materials and new technologies.In the field of ferrites too there has been considerable interest to devise new materials based on iron oxides and other compounds. This means synthesising ultra fine particles and tuning its properties to device new materials. There are various preparation techniques ranging from top- down to bottom-up approaches. This includes synthesising at molecular level, self assembling,gas based condensation. Iow temperature eo-precipitation, solgel process and high energy ball milling. Among these methods sol-gel process allows good control of the properties of ceramic materials. The advantage of this method includes processing at low temperature. mixing at the molecular level and fabrication of novel materials for various devices.Composites are materials. which combine the good qualities of one or more components. They can be prepared in situ or by mechanical means by the incorporation of fine particles in appropriate matrixes. The size of the magnetic powders as well as the nature of matrix affect the processability and other physical properties of the final product. These plastic/rubber magnets can in turn be useful for various applications in different devices. In applications involving ferrites at high frequencies, it is essential that the material possesses an appropriate dielectric permittivity and suitable magnetic permeability. This can be achieved by synthesizing rubber ferrite composites (RFC's). RFCs are very useful materials for microwave absorptions. Hence the synthesis of ferrites in the nanoregirne.investigations on their size effects on the structural, magnetic, and electrical properties and the incorporation of these ferrites into polymer matrixes assume significance.In the present study, nano particles of NiFe204, Li(!5Fe2S04 and Col-e-O, are prepared by sol gel method. By appropriate heat treatments, particles of different grain sizes are obtained. The structural, magnetic and electrical measurements are evaluated as a function of grain size and temperature. NiFel04 prepared in the ultrafine regime are then incorporated in nitrile rubber matrix. The incorporation was carried out according to a specific recipe and for various loadings of magnetic fillers. The cure characteristics, magnetic properties, electrical properties and mechanical properties of these elastomer blends are carried out. The electrical permittivity of all the rubber samples in the X - band are also conducted.

Does the collective strategy ensure the small and medium sized perdurability?

El posicionamiento estratégico se define como el punto de partida de toda reflexión de la organización (por más pequeña que sea) que pretende poner un lugar dentro de la empresa el”give back” del propio rendimiento. En el caso de la estrategia colectiva, no sólo hay una visión de un dirigente (manager), al contrario hay una gran cantidad de visiones de diferentes gestores, que tendrá que tomar decisiones comunes beneficiosas para sus propios intereses y el común de los intereses de cada empresa. Por lo tanto, es esencial que la situación actual y los objetivos a alcanzar estén claramente definidos desde el comienzo de la elaboración de la estrategia, para evitar las posibles divergencias que puedan poner en riesgo la coherencia de la estrategia. Con los problemas encontrados en la PYME francesa, como el inicio de la actividad, los problemas financieros, la integración organizativa y la competencia y el desarrollo de productos, la estrategia colectiva aparece como una posible solución que permite a la PYME perdurar en el tiempo. En Francia, impulsada por el Gobierno y otras instituciones financieras y administrativas, esta estrategia ha conseguido resultados que antes no se habían pensado, como lo demuestra el estudio de modelo urbano el cuál es presentado en esta investigación. Esta es la razón y el por qué se eligió este tema.

Autobiographical Memory for Stressful Events, Traumatic Memory and Posttraumatic Stress Disorder: A Systematic Review

Stressors and traumatic events may contribute to the development of many psychopathologies, PTSD among them. People with this disorder can present significant cognitive impairments and losses in memory, particularly autobiographical memory (AM).This paper aims to present a systematic review of literature considering changes on autobiographical memory in people exposed to potentially traumatic stressors. Therefore, we performed a computerized search in databases PsycINFO, PubMed, Web of Science and Pilots in March 2012.A total of 29 articles were selected and grouped into three categories: studies comparing Trauma X PTSD, studies comparing PTSD X Trauma X Control and comparison studies according to post-traumatic symptoms. Results demonstrate that people with PTSD presents alterations in a larger number of AM components compared to the cases in which PTSD did not developed. In the same way, subjects never exposed to trauma did not demonstrate significant alterations on  AM when compared to the other groups. The results of this study allowed concluding that changes of some components of the AM are primarily associated with PTSD, but it was not possible to clarify whether such changes are related to the timely development of the disorder, or if they are also observed in traumatic memories even in the absence of disorder.

Rearrangement of the urban space in the sector of Saint Victorino and Saint Ines (Bogota) in relation with the dynamics of informality and marginality (1948-2010)

The present article analyze the urban transformations happened in the sector of Saint Victorino and Saint Ines in the city of Bogota D.C. between 1948 and 2010, making use of the "Genealogical Methodology" during the process of inquiry that allow to contrast the visions that are usually accepted of "progress" and "urban renovation" in the urban market context by the existence of a informal economic and a population in conditions of marginality that configures a good part of the "popular urban culture" of the Bogota in the 20th and 21st century. This vision permit to observe from various perspectives the changes that happened in this sector of the city, the impacts of the history facts occurred en this time period and, in special, the real effects of a rearrangement urban process that began in 1998 and has been prolonged to date, which has left a significant mark about the urban and social physiognomy of the place.

The dialectic of silence and remembrance in Lily Brett’s ''Things could be worse''

The dynamics of silence and remembrance in Australian writer Lily Brett’s autobiographic fiction Things Could Be Worse reflects the crisis of memory and understanding experienced by both first and second-generation Holocaust survivors within the diasporic space of contemporary Australia. It leads to issues of handling traumatic and transgenerational memory, the latter also known as postmemory (M. Hirsch), in the long aftermath of atrocities, and problematises the role of forgetting in shielding displaced identities against total dissolution of the self. This paper explores the mechanisms of remembrance and forgetting in L. Brett’s narrative by mainly focusing on two female characters, mother and daughter, whose coming to terms with (the necessary) silence, on the one hand, and articulated memories, on the other, reflects different modes of comprehending and eventually coping with individual trauma. By differentiating between several types of silence encountered in Brett’s prose (that of the voiceless victims, of survivors and their offspring, respectively), I argue that silence can equally voice and hush traumatic experience, that it is never empty, but invested with individual and collective meaning. Essentially, I contend that beside the (self-)damaging effects of silence, there are also beneficial consequences of it, in that it plays a crucial role in emplacing the displaced, rebuilding their shattered self, and contributing to their reintegration, survival and even partial healing.

Socio-cultural visions of interactivity within Museums

The ideas on which this paper is based are drawn from my thesis “Interactivity in Museums. A Relationship Building Perspective” written in 2007 for the fulfillment of the Master Degree in Museology at the Reinwardt Academy in Amsterdam. The main arguments are that the notion of Interactivity conceptualized within a technological orientation coupled with the pedagogic approach of mere information transmission need to be reconsidered; that Interactivity in museums is a conception both misinterpreted and under-implemented; and that the problems of understanding Interactivity will resolve by identifying the aspects which define Interactivity and most importantly focus on why they matter in a broader socio-cultural context within museums. Without an intention to attribute all the developments and advances associated with new museological practice, in some deterministic way, solely to politics and economic change, I argue that the new strategies adopted by museums towards progression and broader accessibility –at least regarding interactivity, seem to be linked more with a dominant commercialization of culture and education, than with a belief towards an effect on social change through the promotion of social interaction within a pluralistic and multicultural society, acknowledging the diversity of nature, opinion and practices, which can be combined instead of contrasting each other.

Reduced heart rate responding to trauma reliving in trauma survivors with PTSD: correlates and consequences

The authors investigated whether heart rate (HR) responses to voluntary recall of trauma memories (a) are related to posttraumatic stress disorder (PTSD), and (b) predict recovery 6 months later. Sixty-two assault survivors completed a recall task modeled on imaginal reliving in the initial weeks postassault. Possible cognitive modulators of HR responsivity were assessed; dissociation, rumination, trauma memory disorganization. Individuals with PTSD showed a reduced HR response to reliving compared to those without PTSD, but reported greater distress. Notably, higher HR response but not self-reported distress during reliving predicted greater symptom reduction at follow-up in participants with PTSD. Engagement in rumination was the only cognitive factor that predicted lower HR response. The data are in contrast to studies using trauma reminders to trigger memories, which have found greater physiological reactivity in PTSD. The authors' observations are consistent with models of PTSD that highlight differences between cued or stimulus-driven retrieval and intentional trauma recall, and with E B. Foa and M.J. Kozak (1986) hypothesis that full activation of trauma memories facilitates emotional processing.

Imagery rescripting as a brief stand-alone treatment for depressed patients with intrusive memories

Many depressed patients report intrusive and distressing memories of specific events in their lives. Where present, these memories are believed to act as a maintaining factor. A series of ten patients with major depressive disorder and intrusive memories, many of them reporting severe, chronic, or recurrent episodes of depression, were given an average of 8.1 sessions of imagery rescripting as a stand-alone treatment. Hierarchical linear modelling demonstrated large treatment effects that were well maintained at one year follow-up. Seven patients showed reliable improvement, and six patients clinically significant improvement. These gains were achieved entirely by working through patients' visual imagination and without verbal challenging of negative beliefs. Spontaneous changes in beliefs, rumination, and behaviour were nevertheless observed. (C) 2009 Elsevier Ltd. All rights reserved.

Queer sex in the metropolis? Place, subjectivity and the Second World War

The strong links between cities and queer culture and its expression have occupied numerous scholars, including Henning Bech and Matt Houlbrook. Indeed, London has been viewed as a focal point of British queer urban culture for over 200 years and, as this article demonstrates, the advent of the Second World War did not preclude this centrality but ensured that the city became a focal point for service personnel on leave. Yet, the emphasis placed on the metropolises in analysing space and queer expression has rendered invisible the use of more transient spaces outside of the city. This article seeks to examine these ‘alternative’ or opportunistic sites of expression, using oral testimony from queer men who served with the British Armed Forces during the Second World War. The memories of these servicemen and the significance they place on space/locations demonstrate the need to engage with subjective sites or ‘geographies’ of queerness both inside and outside of the city between 1939 and 1945.

Autobiographical memory and the self in a case of transient epileptic amnesia

Transient epileptic amnesia (TEA) is characterized by deficits in autobiographical memory (AM). One of the functions of AM is to maintain the self, suggesting that the self may undergo changes as a result of memory loss in temporal lobe epilepsy. To examine this, we used a modification of a task used to assess the relationship between self and memory (the IAM task) in a single case, E.B. Despite complaints of AM loss, E.B. had no difficulty in producing a range of self-images (e.g., I am a husband) and collections of self-defining AMs in support of these statements. E.B. produced fewer episodic memories at times of self-formation, but this did not seem to impact on the maintenance of self. The results support recent work suggesting the self may be maintained in the absence of episodic memory. The application of tasks such as that used here will further elucidate AM impairment in temporal lobe epilepsy. (C) 2011 Elsevier Inc. All rights reserved.

Autobiographical memory and amnesia: using conceptual knowledge to ground the self

A case of retrograde amnesia, PJM, elucidated the relationship between self, episodic memory and autobiographical knowledge. Results from a variety of measures including the I Am Memory Task (IAM Task), where memories are cued by self-generated self concepts, demonstrate that PJM has a coherent, continuous sense of self, despite having lost episodic memories for an 18-month period. Her use of conceptual autobiographical knowledge, in episodic tasks and to support aspects of identity, shows how autobiographical knowledge can support the self when episodic memories are inaccessible. These results are discussed with relation to current neuropsychological models of self and memory.

Are conventions solutions to uncertainty? Contrasting visions of social coordination

In recent years, there has been an increase in research on conventions motivated by the game-theoretic contributions of the philosopher David Lewis. Prior to this surge in interest, discussions of convention in economics had been tied to the analysis of John Maynard Keynes's writings. These literatures are distinct and have very little overlap. Yet this confluence of interests raises interesting methodological questions. Does the use of a common term, convention, denote a set of shared concerns? Can we identify what differentiates the game theoretic models from the Keynesian ones? This paper maps out the three most developed accounts of convention within economics and discusses their relations with each other in an attempt to provide an answer.