914 resultados para the second law of thermodynamics


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This doctoral study aims to understand how experiences of critical illness or bereavement affect the way managers view and approach their work and their relationships at work. This is an interpretative phenomenological study examining the subjective meanings of personal experience and is underpinned by biographic narratives from four participants and interviews with their nominated workplace witnesses (i.e. colleagues who worked alongside the individual at the time of their trauma). As a consequence of the findings that have emerged across this study, three contributions to theory are presented. All four participants described their traumas as a professional growth experience for themselves as managers, which resulted in self-reported and observed behaviour change at work. Consequently, the first area of theoretical contribution is a suggested extension to the post-traumatic growth (PTG) framework (Calhoun & Tedeschi, 2006) with the addition of a new behavioural dimension called ‘managerial growth’, when applied to the context of ‘ordinary’ organizations. The second area of theoretical contribution arose through the reflexive process that was created during data collection where participants and their witnesses remembered episodes of compassion interaction at work. The second area of contribution thus seeks to extend the existing model of compassion at work (Dutton, Worline, Frost and Lilius, 2006), by conceptualising compassion as a dyadic process between a compassion ‘giver’ and a compassion ‘receiver’ in which the compassion receiver ‘trusts or ‘mistrusts’; ‘discloses’ or ‘withholds’; ‘connects’ or ‘disconnects’ with the compassion giver. The third area of contribution is a new conceptualisation of reflexivity, ‘three-dimensional reflexivity’ (3DR) (Armstrong, Butler and Shaw, 2013). 3DR brings together three of the elements that have been missing from critically reflexive management research; by working with multiple variants of reflexivity in the same study; surfacing different reflexive voices to guard against the researcher’s (potentially) solipsistic own; and remaining sensitive to the concept of reflexive time. In doing so, 3DR not only provides a deeper understanding of individual lived experience; it is also a vehicle in which self-insight is gained. Furthermore, by engaging in its practice, those involved in this study have developed both personally and professionally as a result.

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* This paper was made according to the program of fundamental scientific research of the Presidium of the Russian Academy of Sciences «Mathematical simulation and intellectual systems», the project "Theoretical foundation of the intellectual systems based on ontologies for intellectual support of scientific researches".

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The volume The Dialectics of Modernity - Recognizing Globalization. Studies on the Theoretical Perspectives of Globalization is the product of a work of that quarter of the century, which has been continuing, since 1989 up today, the true beginning of the globalization. Therefore, because that concept was not existing at that time, the work is not yet directed, in the first years, on the globalization itself. As it can be seen, this concept pushed through only in the second half of the nineties, when the concept could also be already statistically revealed in the world press. How a group of researchers from Hungary was enquirying during the nineties, according to partners of conversation at home and abroad, with whom one could talk about how the new world emerging with 1989 can actually be described, is a long story, the theory of which consists in the fact, that we apparently live in a world, where the most part of the people, even worse, even most of the intellectuals are hardly interested in how this one really looks like. On looking for partners, the circle of the authors of this volume was created. In Hungary, we quickly reached our limit (which much later did not prevent us from appearing, such as if we had always been living in the theoretically worked globalization). The French group around Jacques Poulain reacted the fastest way (and later around Francois de Bernard, with his particularly valuable homepage www.mondialisations.org), not much later the contact with the Russian colleagues around Alexandr Shumakov was created, in which Encyclopedia of the Globalization our contribution could already appear in 2003. On these traces, we came to the productive relationship with Leonid Grinin and Andrey Korotayev. Finally, we mention the Fürstenfeld's initiative, founded since 2009 with Melitta Becker's help in the framework of the Centre for the Interdisciplinary Research in this Austrian city. A relevant part of the author inside this book participated from the beginning in the work of the group. The individual contributions to this volume are linked together by a common interest in knowledge. This is the theoretical view of the phenomenon of the globalization. From the beginning, it was not further defined or limited to certain approaches, particularly an independent theory of the globalization was not intended. We started from the fact, that every legitimately revealed theoretical approach can contribute legitimately to a later theory of the globalization. In this way, the further contacts with Nico Stehr and the members of the Dresden group for the investigation of the security problems arose, mainly with Ernst Woit. Hegel defined the philosophy as the flight of the Owl of Minerva, which "begins its flight only with the falling twilight". Through the theoretical investigation of the globalization always becoming interdisciplinary, we wanted by no means to debate about this incomparable aphorism. We simply started from the conviction, that a new reality should not remain without any description.

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Glass is a common form of trace evidence found at many scenes of crimes in the form of small fragments. These glass fragments can transfer to surrounding objects and/or persons and may provide forensic investigators valuable information to link a suspect to the scene of a crime. Since the elemental composition of different glass sources can be very similar, a highly discriminating technique is required to distinguish between fragments that have originated from different sources. ^ The research presented here demonstrates that Laser Induced Breakdown Spectroscopy (LIBS) is a viable analytical technique for the association and discrimination of glass fragments. The first part of this research describes the optimization of the LIBS experiments including the use of different laser wavelengths to investigate laser-material interaction. The use of a 266 nm excitation laser provided the best analytical figures of merit with minimal damage to the sample. The resulting analytical figures of merit are presented. The second part of this research evaluated the sensitivity of LIBS to associate or discriminate float glass samples originating from the same manufacturing plants and produced at approximately the same time period. Two different sample sets were analyzed ranging in manufacturing dates from days to years apart. Eighteen (18) atomic emission lines corresponding to the elements Sr, K, Fe, Ca, Al, Ba, Na, Mg and Ti, were chosen because of their detection above the method detection limits and for presenting differences between the samples. Ten elemental ratios producing the most discrimination were selected for each set. When all the ratios are combined in a comparison, 99% of the possible pairs were discriminated using the optimized LIBS method generating typical analytical precisions of ∼5% RSD. ^ The final study consisted of the development of a new approach for the use of LIBS as a quantitative analysis of ultra-low volume solution analysis using aerosols and microdrops. Laser induced breakdown spectroscopy demonstrated to be an effective technique for the analysis of as low as 90 pL for microdrop LIBS with 1 pg absolute LOD and 20 µL for aerosol LIBS with an absolute LOD of ∼100 fg.^

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Elemental analysis can become an important piece of evidence to assist the solution of a case. The work presented in this dissertation aims to evaluate the evidential value of the elemental composition of three particular matrices: ink, paper and glass. In the first part of this study, the analytical performance of LIBS and LA-ICP-MS methods was evaluated for paper, writing inks and printing inks. A total of 350 ink specimens were examined including black and blue gel inks, ballpoint inks, inkjets and toners originating from several manufacturing sources and/or batches. The paper collection set consisted of over 200 paper specimens originating from 20 different paper sources produced by 10 different plants. Micro-homogeneity studies show smaller variation of elemental compositions within a single source (i.e., sheet, pen or cartridge) than the observed variation between different sources (i.e., brands, types, batches). Significant and detectable differences in the elemental profile of the inks and paper were observed between samples originating from different sources (discrimination of 87–100% of samples, depending on the sample set under investigation and the method applied). These results support the use of elemental analysis, using LA-ICP-MS and LIBS, for the examination of documents and provide additional discrimination to the currently used techniques in document examination. In the second part of this study, a direct comparison between four analytical methods (µ-XRF, solution-ICP-MS, LA-ICP-MS and LIBS) was conducted for glass analyses using interlaboratory studies. The data provided by 21 participants were used to assess the performance of the analytical methods in associating glass samples from the same source and differentiating different sources, as well as the use of different match criteria (confidence interval (±6s, ±5s, ±4s, ±3s, ±2s), modified confidence interval, t-test (sequential univariate, p=0.05 and p=0.01), t-test with Bonferroni correction (for multivariate comparisons), range overlap, and Hotelling's T2 tests. Error rates (Type 1 and Type 2) are reported for the use of each of these match criteria and depend on the heterogeneity of the glass sources, the repeatability between analytical measurements, and the number of elements that were measured. The study provided recommendations for analytical performance-based parameters for µ-XRF and LA-ICP-MS as well as the best performing match criteria for both analytical techniques, which can be applied now by forensic glass examiners.

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Predators exert strong direct and indirect effects on ecological communities by intimidating their prey. Non-consumptive effects (NCEs) of predators are important features of many ecosystems and have changed the way we understand predator-prey interactions, but are not well understood in some systems. For my dissertation research I combined a variety of approaches to examine the effect of predation risk on herbivore foraging and reproductive behaviors in a coral reef ecosystem. In the first part of my dissertation, I investigated how diet and territoriality of herbivorous fish varied across multiple reefs with different levels of predator biomass in the Florida Keys National Marine Sanctuary. I show that both predator and damselfish abundance impacted diet diversity within populations for two herbivores in different ways. Additionally, reef protection and the associated recovery of large predators appeared to shape the trade-off reef herbivores made between territory size and quality. In the second part of my dissertation, I investigated context-dependent causal linkages between predation risk, herbivore foraging behavior and resource consumption in multiple field experiments. I found that reef complexity, predator hunting mode, light availability and prey hunger influenced prey perception of threat and their willingness to feed. This research argues for more emphasis on the role of predation risk in affecting individual herbivore foraging behavior in order to understand the implications of human-mediated predator removal and recovery in coral reef ecosystems.^

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This work presents the numerical analysis of nonlinear trusses summited to thermomechanical actions with Finite Element Method (FEM). The proposed formulation is so-called positional FEM and it is based on the minimum potential energy theorem written according to nodal positions, instead of displacements. The study herein presented considers the effects of geometric and material nonlinearities. Related to dynamic problems, a comparison between different time integration algorithms is performed. The formulation is extended to impact problems between trusses and rigid wall, where the nodal positions are constrained considering nullpenetration condition. In addition, it is presented a thermodynamically consistent formulation, based on the first and second law of thermodynamics and the Helmholtz free-energy for analyzing dynamic problems of truss structures with thermoelastic and thermoplastic behavior. The numerical results of the proposed formulation are compared with examples found in the literature.

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A high-resolution study of benthic foraminiferal assemblages was performed on a ca. eight metre long sediment core from Gullmar Fjord on the west coast of Sweden. The results of 210Pb- and AMS 14C-datings show that the record includes the two warmest climatic episodes of the last 1500 years: the Medieval Warm Period (MWP) and the recent warming of the 20th century. Both periods are known to be anomalously warm and associated with positive NAO winter indices. Benthic foraminiferal successions of both periods are compared in order to find faunal similarities and common denominators corresponding to past climate changes. During the MWP, Adercotryma glomerata, Cassidulina laevigata and Nonionella iridea dominated the assemblages. Judging from dominance of species sensitive to hypoxia and the highest faunal diversity for the last ca. 2400 years, the foraminiferal record of the MWP suggests an absence of severe low oxygen events. At the same time, faunas and d13C values both point to high primary productivity and/or increased input of terrestrial organic carbon into the fjord system during the Medieval Warm Period. Comparison of the MWP and recent warming revealed different trends in the faunal record. The thin-shelled foraminifer N. iridea was characteristic of the MWP, but became absent during the second half of the 20th century. The recent Skagerrak-Kattegat fauna was rare or absent during the MWP but established in Gullmar Fjord at the end of the Little Ice Age or in the early 1900s. Also, there are striking differences in the faunal diversity and absolute abundances of foraminifera between both periods. Changes in primary productivity, higher precipitation resulting in intensified land runoff, different oxygen regimes or even changes in the fjord's trophic status are discussed as possible causes of these faunal differences.

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At least two modes of glacial-interglacial climate change have existed within the tropical Atlantic Ocean during the last 20,000 years. The first mode (defined by cold glacial and warm interglacial conditions) occurred symmetrically north and south of the equator and dominated the eastern boundary currents and tropical upwelling areas. This pattern suggests that mode 1 is driven by a glacial modification of surface winds in both hemispheres. The second mode of oceanic climate change, defined by temperature extremes centered on the deglaciation, was hemispherically asymmetrical, with the northern tropical Atlantic relatively cold and the southern tropical Atlantic relatively warm during deglaciation. A likely cause for this pattern of variation is a reduction of the presently northward cross-equatorial heat flux during deglaciation. No single mechanism accounts for all the data. Potential contributors to oceanic climate changes are linkage to high-latitude climates, modification of monsoonal winds by ice sheet and/or insolation changes, atmospheric CO2 and greenhouse effects, indirect effects of glacial meltwater, and variations in thermohaline overturn of the oceans.

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This thesis divides into two distinct parts, both of which are underpinned by the tight-binding model. The first part covers our implementation of the tight-binding model in conjunction with the Berry phase theory of electronic polarisation to probe the atomistic origins of spontaneous polarisation and piezoelectricity as well as attempting to accurately calculate the values and coefficients associated with these phenomena. We first develop an analytic model for the polarisation of a one-dimensional linear chain of atoms. We compare the zincblende and ideal wurtzite structures in terms of effective charges, spontaneous polarisation and piezoelectric coefficients, within a first nearest neighbour tight-binding model. We further compare these to real wurtzite structures and conclude that accurate quantitative results are beyond the scope of this model but qualitative trends can still be described. The second part of this thesis deals with implementing the tight-binding model to investigate the effect of local alloy fluctuations in bulk AlGaN alloys and InGaN quantum wells. We calculate the band gap evolution of Al1_xGaxN across the full composition range and compare it to experiment as well as fitting bowing parameters to the band gap as well as to the conduction band and valence band edges. We also investigate the wavefunction character of the valence band edge to determine the composition at which the optical polarisation switches in Al1_xGaxN alloys. Finally, we examine electron and hole localisation in InGaN quantum wells. We show how the built-in field localises the carriers along the c-axis and how local alloy fluctuations strongly localise the highest hole states in the c-plane, while the electrons remain delocalised in the c-plane. We show how this localisation affects the charge density overlap and also investigate the effect of well width fluctuations on the localisation of the electrons.

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Predators exert strong direct and indirect effects on ecological communities by intimidating their prey. Non-consumptive effects (NCEs) of predators are important features of many ecosystems and have changed the way we understand predator-prey interactions, but are not well understood in some systems. For my dissertation research I combined a variety of approaches to examine the effect of predation risk on herbivore foraging and reproductive behaviors in a coral reef ecosystem. In the first part of my dissertation, I investigated how diet and territoriality of herbivorous fish varied across multiple reefs with different levels of predator biomass in the Florida Keys National Marine Sanctuary. I show that both predator and damselfish abundance impacted diet diversity within populations for two herbivores in different ways. Additionally, reef protection and the associated recovery of large predators appeared to shape the trade-off reef herbivores made between territory size and quality. In the second part of my dissertation, I investigated context-dependent causal linkages between predation risk, herbivore foraging behavior and resource consumption in multiple field experiments. I found that reef complexity, predator hunting mode, light availability and prey hunger influenced prey perception of threat and their willingness to feed. This research argues for more emphasis on the role of predation risk in affecting individual herbivore foraging behavior in order to understand the implications of human-mediated predator removal and recovery in coral reef ecosystems.

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Don Draper (Mad Men, Matthew Weiner, AMC: 2007-2015) actively colaborates in the birth and consolidationof a model of consumer society without realizing the enormous lie he is telling himself. Tony Soprano(The Sopranos, David Chase, HBO: 1999-2007) desperately grasps the wreckage of that ideal imageof effort and self-improvement which is not only disappearing but was actually never coherent or real.This article does a comparative textual, sociological, and discursive analysis these two characters as arepresentation of the evolution of the discourse of capitalism in the second half of the 20th century, that is,the artificiality of the hegemonic discourse of “pursuit of happiness” as the main myth in post-war NorthAmerican neoliberalism.

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Since the second half of 1990s, the economic impact of sports mega-events concerned the researchers, the public and the professionals. The investment of public funds and the effects on several sectors of the economy motivate the economic impact studies. The economic impact of the FIS Nordic World Ski Championship Falun 2015 to the region of Dalarna is the topic of this thesis. This requires the calculation of direct, indirect and induced economic impact. Within the analysis, data from a questionnaire survey conducted on seven different days during the event are used. The final sample of the analysis contains 893 observations. The segmentation approach was applied for the calculations and the visitors were classified regarding their choice of accommodation. The regional economic impact is calculated at 321 M SEK and the employment effect on the tourism sector is estimated. However, the lack of information limits the study. The analysis could be extended with an accurate investigation of certain issues. Further, the impact of the event should be estimated from all the perspectives. The organization of sports mega-events creates tangible and intangible effects to the host-city. The thesis reviews literature on the economic impact studies of sports mega-events. The results of the study can be used for a comprehensive analysis of the case study. Further, the professionals of the tourism and the event could be benefited.

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In the first part of this thesis, the oncogenic potential of TCL1A family genes was comparatively evaluated by using gamma-retroviral vectors to introduce human TCL1A, MTCP1, and TML1 into hematopoietic stem cells/hematopoietic progenitor cells (HSC/HPC) of wild type mice that were transplanted into wild type recipients. TCL1A and MTCP1 recipient mice predominantly developed B-cell malignancies after a median survival of 388 days and 394 days, respectively. The presented data indicates that TCL1A and MTCP1 are oncogenes with comparable oncogenic potential and shows for the first time that MTCP1 is not only a T-cell oncogene, but is able to transform B cells as well. The third family member TML1 induced the development of immature T-cell malignancies in only a few mice. This study provides first evidence for its oncogenic function. Additionally, the transforming potential of compartment-targeted TCL1A variants was evaluated by retroviral expression of a membrane localizing myristoylated (myr-TCL1A) and a nuclear localizing (nls-TCL1A) variant. Recipients of HSC/HPC transduced with myr-TCL1A and nls-TCL1A predominantly developed B-cell malignancies after a median survival of 360 days and 349 days, respectively. There was a significantly shorter latency period for nls-TCL1A compared to the previously described generic TCL1A. Gene expression analysis revealed higher similarities between expression profiles of tumors induced by TCL1A and nls-TCL1A. Together these data implicate that TCL1A’s predominant oncogenic function might rely on its nuclear presence. The second part of this thesis aims to understand if and how TCR stimulation affects the transforming potential of TCL1A. Mature OT-1 T cells carrying monoclonal TCR’s that specifically recognize ovalbumin (OVA) were retrovirally transduced with TCL1A and repeatedly stimulated in vivo with OVA-peptides. TCR stimulated recipient mice of TCL1A transduced T cells showed a significantly accelerated leukemic outgrowth and a reduced median survival of 305 days, when compared to unstimulated recipients (417 days). These data strongly implicate a pro-leukemogenic cooperation of TCL1A and TCR signals that might be actionable in upcoming interventional designs.