892 resultados para Phenomenon of disinterest


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The redox stratification of bottom sediments in Kandalaksha Bay, White Sea, is characterized by elevated concentrations of Mn (3-5%) and Fe (7.5%) in the uppermost layer, which is two orders of magnitude and one and a half times, respectively, higher than the average concentrations of these elements in the Earth's crust. The high concentrations of organic matter (Corg = 1-2%) in these sediments cannot maintain (because of its low reaction activity) the sulfate-reducing process (the concentration of sulfide Fe is no higher than 0.6%). The clearest manifestation of diagenesis is the extremely high Mn2+ concentration in the silt water (>500 µM), which causes its flux into the bottom water, oxidation in contact with oxygen, and the synthesis of MnO2 oxy-hydroxide enriching the surface layer of the sediments. Such migrations are much less typical of Fe. Upon oxygen exhaustion in the uppermost layer of the sediments, the synthesized oxyhydroxides (MnO2 and FeOOH) serve as oxidizers of organic matter during anaerobic diagenesis. The calculated diffusion-driven Mn flux from the sediments (280 µM/m**2 day) and corresponding amount of forming Mn oxyhydrate as compared to opposite oxygen flux to sediments (1-10 mM/m**2 day) indicates that >10% organic matter in the surface layer of the sediments can be oxidized with the participation of MnO2. The roles of other oxidizers of organic matter (FeOOH and SO4**2-) becomes discernible at deeper levels of the sediments. The detailed calculation of the balance of reducing processes testifies to the higher consumption of organic matter during the diagenesis of surface sediments than it follows from the direct determination of Corg. The most active diagenetic redox processes terminate at depths of 25-50 cm. Layers enriched in Mn at deeper levels are metastable relicts of its surface accumulation and are prone to gradual dissemination.

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During nanoindentation and ductile-regime machining of silicon, a phenomenon known as “self-healing” takes place in that the microcracks, microfractures, and small spallings generated during the machining are filled by the plastically flowing ductile phase of silicon. However, this phenomenon has not been observed in simulation studies. In this work, using a long-range potential function, molecular dynamics simulation was used to provide an improved explanation of this mechanism. A unique phenomenon of brittle cracking was discovered, typically inclined at an angle of 45° to 55° to the cut surface, leading to the formation of periodic arrays of nanogrooves being filled by plastically flowing silicon during cutting. This observation is supported by the direct imaging. The simulated X-ray diffraction analysis proves that in contrast to experiments, Si-I to Si-II (beta tin) transformation during ductile-regime cutting is highly unlikely and solid-state amorphisation of silicon caused solely by the machining stress rather than the cutting temperature is the key to its brittle-ductile transition observed during the MD simulations

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Background: Potentially inappropriate prescribing (PIP) is common in older people in primary care, as evidenced by a significant body of quantitative research. However, relatively few qualitative studies have investigated the phenomenon of PIP and its underlying processes from the perspective of general practitioners (GPs). The aim of this paper is to explore qualitatively, GP perspectives regarding prescribing and PIP in older primary care patients.

Method: Semi-structured qualitative interviews were conducted with GPs participating in a randomised controlled trial (RCT) of an intervention to decrease PIP in older patients (≥70 years) in Ireland. Interviews were conducted with GP participants (both intervention and control) from the OPTI-SCRIPT cluster RCT as part of the trial process evaluation between January and July 2013. Interviews were conducted by one interviewer and audio recorded. Interviews were transcribed verbatim and a thematic analysis was conducted.

Results: Seventeen semi-structured interviews were conducted (13 male; 4 female). Three main, inter-related themes emerged (complex prescribing environment, paternalistic doctor-patient relationship, and relevance of PIP concept). Patient complexity (e.g. polypharmacy, multimorbidity), as well as prescriber complexity (e.g. multiple prescribers, poor communication, restricted autonomy) were all identified as factors contributing to a complex prescribing environment where PIP could occur, as was a paternalistic-doctor patient relationship. The concept of PIP was perceived to be of variable usefulness to GPs and the criteria to measure it may be at odds with the complex processes of prescribing for this patient population.

Conclusions: Several inter-related factors contributing to the occurrence of PIP were identified, some of which may be amenable to intervention. Improvement strategies focused on improved management of polypharmacy and multimorbidity, and communication across primary and secondary care could result in substantial improvements in PIP.

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Learning to live with diabetes in such a way that the new conditions will be a normal and natural part of life imposes requirements on the person living with diabetes. Previous studies have shown that there is no clear picture of what and how the learning that would allow persons to incorporate the illness into their everyday life will be supported. The aim of this study is to describe the phenomenon of support for learning to live with diabetes to promote health and well-being, from the patient's perspective. Data were collected by interviews with patients living with type 1 or type 2 diabetes. The interviews were analysed using a reflective lifeworld approach. The results show that reflection plays a central role for patients with diabetes in achieving a new understanding of the health process, and awareness of their own responsibility was found to be the key factor for such a reflection. The constituents are responsibility creating curiosity and willpower, openness enabling support, technology verifying bodily feelings, a permissive climate providing for participation and exchanging experiences with others. The study concludes that the challenge for caregivers is to create interactions in an open learning climate that initiates and supports reflection to promote health and well-being.

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The phenomenon of patterned distribution of pH near the cell membrane of the algae Chara corallina upon illumination is well-known. In this paper, we develop a mathematical model, based on the detailed kinetic analysis of proton fluxes across the cell membrane, to explain this phenomenon. The model yields two coupled nonlinear partial differential equations which describe the spatial dynamics of proton concentration changes and transmembrane potential generation. The experimental observation of pH pattern formation, its period and amplitude of oscillation, and also its hysteresis in response to changing illumination, are all reproduced by our model. A comparison of experimental results and predictions of our theory is made. Finally, a mechanism for pattern formation in Chara corallina is proposed.

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Abstract : The use of social media tools to support small and medium-sized enterprises (SME) to support their business activities throughout the product life cycle (PLC) phases represents an interesting opportunity. SMEs operate in very competitive environments, and face significant challenges primarily caused by their size disadvantage. By nature, social media tools and platforms can enable them to overcome some of these challenges, as they are often very inexpensive, familiar and easy to use, allowing them to reach large audiences they would not be able to reach with traditional and expensive marketing initiatives. To provide solutions to this problem, this research identified three main objectives. The first objective was to draw a picture of the existing academic literature on the use of social media tools in the PLC context to better understand how these tools were studied and used in businesses, and for what purpose. Second, this research aimed at understanding how SMEs actually use social media tools to support their different business activities to identify the gap between academic research and actual business practices. Finally, based on the findings highlighted from the previous objectives, this research aimed at developing theory on this topic by proposing a conceptual framework of customer engagement enabled by social media. The conceptual framework aimed at answering general questions that emerged from the initial two objectives: Why do some SMEs use social media to support customer engagement, while others do not? Why do firms use different social media tools to support their customer engagement initiatives? Why does the scope of customer engagement initiatives (i.e., across different PLC phases) vary between SMEs? What are the potential outcomes of conducting customer engagement initiatives for the organizing firms? In order to achieve these research objectives, the methodology employed for this research is threefold. First, a systematic literature review was performed in order to properly understand how the use of social media tools in the PLC context had been studied. The final results consisted of 78 academic articles which were analyzed based on their bibliometric information and their content. Second, in order to draw the contrast between the academic publications and managerial reality of SMEs, six semi-structured interviews were conducted to understand how these firms actually use social media to support different activities in each of the PLC phases. Third, five additional semi-structured interviews were performed to gather a deeper understanding of this phenomenon and generate theory to support the proposed conceptual framework. The conceptual framework focuses on the degree of customer engagement, which is comprised of the scope (PLC phases) of customer engagement and the technology (social media tools) employed to support these initiatives. Two sets of antecedents were examined, firm motivators and firm impediments, as they could both potentially affect the scope and the social media tools used to support customer engagement initiatives. Finally, potential customer engagement outcomes for SMEs developing these initiatives were also examined. The semi-structured interviews lasted approximately 25-35 minutes, and were performed using an interview grid consisting of 24 open-ended questions. The interview grid was developed based on the findings of the systematic literature review, and this qualitative approach allowed for a rich understanding of the interviewed SMEs’ use of social media tools to support and engage customers in their different PLC activities. The main results highlighted by this project demonstrate that this field is relatively recent and sees constant increase in research interest since 2008. However, most of the academic research focuses on the use of social media tools to support innovation activities during the new product development process, while the interviewed firms almost exclusively used the tools to engage customers in the later phases of the PLC, primarily for promotion, customer service support, and business development activities. Interestingly, the interviewed firms highlighted several benefits of using social media tools to engage customers, some of which could help them overcome certain size disadvantages previously mentioned. These firms are in need of further guidelines to properly implement such initiatives and reap the expected benefits. Results suggest that SMEs are far behind both large companies and academic research in their use of social media to engage customers in different business activities. The proposed conceptual framework serves as a great tool to better understand their reality and eventually better support them in their social media and customer engagement efforts. However, this framework needs to be further developed and improved. This research project provides a 360-degree view of the phenomenon of the use of social media to support customer engagement for SMEs, by providing both a thorough systematic review of the academic research and an understanding of the managerial reality of SMEs behind this phenomenon. From this analysis, a conceptual framework is then proposed and serves as a stepping stone for future researchers who are interested in developing theory in this field.

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Thesis (Ph.D.)--University of Washington, 2016-08

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Purpose – The purpose of this paper is to identify the key determinants of organisational silence from the perspective of non-standard workers (NSWs). The study focuses on three research themes: first, analysing the experiences motivating NSWs to remain silent; second, analysing the role of the NSW life cycle in the motivation to remain silent, the final theme is evaluation of the impact on organisational voice of an organisation employing a workforce in which NSWs and standard workers (SWs) are blended. Design/methodology/approach – The study utilises a phenomenological approach, as defined by Van Manen (2007), to collect and analyse the phenomenon of organisational silence from the perspective of NSWs. The NSWs are defined as individuals operating via Limited Liability UK registered companies created for the purpose of delivering services to organisations via a contract of services. This study employed a combination of phenomenology and hermeneutics to collect and analyse the data collected from the NSWs using semi-structured interviews (Lindseth and Norberg, 2004). Findings – The study concludes with three core findings. NSWs experience similar motivational factors to silence as experienced by standard workers (SWs). The key differential between a SW and a NSW is the role of defensive silence as a dominant motivator for a start-up NSW. The study identified that the reasons for this is that new NSWs are defensive to protect their reputation for any future contract opportunities. In addition, organisations are utilising the low confidence of new start up NSWs to suppress the ability of NSWs to voice. The research indicates how experienced NSWs use the marketing stage of their life cycle to establish voice mechanisms. The study identified that NSWs, fulfiling management and supervisory roles for organisations, are supporting/creating climates of silence through their transfer of experiences as SWs prior to becoming NSWs. Research limitations/implications – This study is a pilot study, and the findings from this study will be carried forward into a larger scale study through engagement with further participants across a diverse range of sectors. This study has identified that there is a need for further studies on organisational silence and NSWs to analyse more fully the impact of silence on the individuals and the organisation itself. A qualitative phenomenological hermeneutical study is not intended to be extrapolated to provide broad trends. The focus of the phenomenological hermeneutic research methodology is on describing and analysing the richness and depth of the NSW’s experiences of silence in organisational settings. Originality/value – This paper draws together the studies of worker classification, motivators for organisational silence, and the impact of blending SWs and NSWs in an organisational setting. The study demonstrates that academic research to date has focused predominantly on SWs to the exclusion of the 1.5 million, and growing, NSWs in the UK. This study examines these under-represented workers to analyse the participants’ experiences of organisational silence, and its consequences in organisational settings, demonstrating a need for further studies.

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The purpose of this quantitative study was to explore the previously unexamined phenomenon of middle school parental engagement in a large urban/suburban/rural school district of 209 schools in the mid-Atlantic region of the United States. Across 22 middle schools serving grades six-eight, this study collected and examined perceptions of the three key adult stakeholder groups – administrators, teachers, and parents – most actively involved in middle school parental engagement as described within the theoretical framework of academic socialization. Their reports of observable parental engagement activities were used to document how district stakeholders operationalize behaviors that represent the five actionable constructs and three themes of academic socialization to determine how the district “fares” in employing academic socialization as a middle school parent engagement strategy. The study also applied quantitative descriptive analysis through a one-way ANOVA to determine the significance of observable variations in actionable constructs between the perspectives of the three stakeholder groups. Finally, the study illuminated, through regression modeling, when confounding factors/independent variables such as race, income, school size, administrator and teacher experience, parents’ educational background, etc., impacted operationalization of academic socialization behaviors for middle school parent and family engagement. Rejecting the null hypothesis, the study found that the three stakeholder groups had statistically significant differences in perceptions of their implementation of activities aligned to academic socialization. This study ultimately illuminated ways in which these adult stakeholder groups share similar and varied perceptions about their engagement actions that support the achievement and maturation of middle school students. Significantly, this study provided key findings that illuminated areas that can be systemically addressed to transform middle school parent engagement practices through applied academic socialization theory into consistent and effective collaborative efforts between the home and school. The process of operationalizing academic socialization was outlined in terms that any school or district can follow to improve programs and practices of middle school parental engagement to serve in the best interests of students during this period of great transition for both child/adolescent growth and development and adult navigation of systems to provide support for students in this unique stage of growth and maturation.

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Land take is a phenomenon of great concern nowadays because of the large number of its negative impacts regarding biological, economic and social balance. In Italy, the development of urban and other artificial land has been irreversibly transforming a nonrenewable resource such as soil, regardless the almost constant population rate, with different speed depending of the region considered. The aim of this paper is to analyze the phenomenon in the metropolitan area of Naples, which is an area highly affected by territorial aggression of human matrix. The data used are both by the Institute for Environmental Protection and Research (ISPRA) Report 2015 on the usage of the land and by ISTAT relating to the resident population up to the 1st of January 2015 and the extension of land for agricultural use (Census 2010). The mathematical combination of this data creates a new indicator that can be referred to as “residual land”; this residual area is of great extension with many different characteristics and it could represent the area where the phenomenon of land take most occurs. The identification, measurement and analysis of “residual land” provide new insights on the evolution of land take and this new indicator can represent a critical element to work on to prevent future land transformation and protect natural and agricultural areas within the Italian context.

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In the present paper, we discuss the time before the “age of reports”. Besides the Coleman Report in the period of Coleman, the Lady Plowden Report also appeared, while there were important studies in France (Bourdieu & Passeron, 1964; Peyre, 1959) and studies that inaugurated comprehensive education in Nordic countries. We focus on the period after the World War II, which was marked by rising economic nationalism, on the one hand, and by the second wave of mass education, on the other, bearing the promise of more equality and a reduction of several social inequalities, both supposed to be ensured by school. It was a period of great expectations related to the power of education and the rise of educational meritocracy. On this background, in the second part of the paper, the authors attempt to explore the phenomenon of the aforementioned reports, which significantly questioned the power of education and, at the same time, enabled the formation of evidence-based education policies. In this part of the paper, the central place is devoted to the case of socialist Yugoslavia/Slovenia and its striving for more equality and equity through education. Through the socialist ideology of more education for all, socialist Yugoslavia, with its exaggerated stress on the unified school and its overemphasised belief in simple equality, overstepped the line between relying on comprehensive education as an important mechanism for increasing the possibility of more equal and just education, on the one hand, and the myth of the almighty unified school capable of eradicating social inequalities, especially class inequalities, on the other. With this radical approach to the reduction of inequalities, socialist policy in the then Yugoslavia paradoxically reduced the opportunity for greater equality, and even more so for more equitable education. (DIPF/Orig.)

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Sediment oxygen demand (SOD) can be a significant oxygen sink in various types of water bodies, particularly slow-moving waters with substantial organic sediment accumulation. In most settings where SOD is a concern, the prevailing hydraulic conditions are such that the impact of sediment resuspension on SOD is not considered. However, in the case of Bubbly Creek in Chicago, Illinois, the prevailing slack water conditions are interrupted by infrequent intervals of very high flow rates associated with pumped combined sewer overflow (CSO) during intense hydrologic events. These events can cause resuspension of the highly organic, nutrient-rich bottom sediments, resulting in precipitous drawdown of dissolved oxygen (DO) in the water column. While many past studies have addressed the dependence of SOD on near-bed velocity and bed shear stress prior to the point of sediment resuspension, there has been limited research that has attempted to characterize the complex and dynamic phenomenon of resuspended-sediment oxygen demand. To address this issue, a new in situ experimental apparatus referred to as the U of I Hydrodynamic SOD Sampler was designed to achieve a broad range of velocities and associated bed shear stresses. This allowed SOD to be analyzed across the spectrum of no sediment resuspension associated with low velocity/ bed shear stress through full sediment resuspension associated with high velocity / bed shear stress. The current study split SOD into two separate components: (1) SODNR is the sediment oxygen demand associated with non-resuspension conditions and is a surface sink calculated using traditional methods to yield a value with units (g/m2/day); and (2) SODR is the oxygen demand associated with resuspension conditions, which is a volumetric sink most accurately characterized using non-traditional methods and units that reflect suspension in the water column (mg/L/day). In the case of resuspension, the suspended sediment concentration was analyzed as a function of bed shear stress, and a formulation was developed to characterize SODR as a function of suspended sediment concentration in a form similar to first-order biochemical oxygen demand (BOD) kinetics with Monod DO term. The results obtained are intended to be implemented into a numerical model containing hydrodynamic, sediment transport, and water quality components to yield oxygen demand varying in both space and time for specific flow events. Such implementation will allow evaluation of proposed Bubbly Creek water quality improvement alternatives which take into account the impact of SOD under various flow conditions. Although the findings were based on experiments specific to the conditions in Bubbly Creek, the techniques and formulations developed in this study should be applicable to similar sites.

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Quantum mechanics, optics and indeed any wave theory exhibits the phenomenon of interference. In this thesis we present two problems investigating interference due to indistinguishable alternatives and a mostly unrelated investigation into the free space propagation speed of light pulses in particular spatial modes. In chapter 1 we introduce the basic properties of the electromagnetic field needed for the subsequent chapters. In chapter 2 we review the properties of interference using the beam splitter and the Mach-Zehnder interferometer. In particular we review what happens when one of the paths of the interferometer is marked in some way so that the particle having traversed it contains information as to which path it went down (to be followed up in chapter 3) and we review Hong-Ou-Mandel interference at a beam splitter (to be followed up in chapter 5). In chapter 3 we present the first of the interference problems. This consists of a nested Mach-Zehnder interferometer in which each of the free space propagation segments are weakly marked by mirrors vibrating at different frequencies [1]. The original experiment drew the conclusions that the photons followed disconnected paths. We partition the description of the light in the interferometer according to the number of paths it contains which-way information about and reinterpret the results reported in [1] in terms of the interference of paths spatially connected from source to detector. In chapter 4 we briefly review optical angular momentum, entanglement and spontaneous parametric down conversion. These concepts feed into chapter 5 in which we present the second of the interference problems namely Hong-Ou-Mandel interference with particles possessing two degrees of freedom. We analyse the problem in terms of exchange symmetry for both boson and fermion pairs and show that the particle statistics at a beam splitter can be controlled for suitably chosen states. We propose an experimental test of these ideas using orbital angular momentum entangled photons. In chapter 6 we look at the effect that the transverse spatial structure of the mode that a pulse of light is excited in has on its group velocity. We show that the resulting group velocity is slower than the speed of light in vacuum for plane waves and that this reduction in the group velocity is related to the spread in the wave vectors required to create the transverse spatial structure. We present experimental results of the measurement of this slowing down using Hong-Ou-Mandel interference.

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The phenomenon of terrorism is one of the most asymmetrical, amorphous and hybrid threats to international security. At the beginning of the 21st century, terrorism grew to a pandemic. Ensuring freedom and security of individuals and nations has become one of the priority postulates. Terrorism steps out of all legal and analytic-descriptive standards. An immanent feature of terrorism, e.g. is constant conversion into malicious forms of violence. One of the most alarming changes is a tendency for debasement of essence of law, a state and human rights Assurance of safety in widely accessible public places and in private life forces creation of various institutions, methods and forms of people control. However, one cannot in an arbitrary way limit civil freedom. Presented article stresses the fact that rational and informed approach to human rights should serve as a reference point for legislative and executive bodies. Selected individual applications to the European Court of Human Rights are presented, focusing on those based on which standards regarding protection of human rights in the face of pathological social phenomena, terrorism in particular, could be reconstructed and refined. Strasbourg standards may prove helpful in selecting and constructing new legal and legislative solutions, unifying and correlating prophylactic and preventive actions.