Electromagnetic control of a free body : design and control of a 6 DOF magnetically levitated spherical laser deflection system

Abstract in thesi

Small bowel and rectal toxicity after pelvic radiotherapy : histopathological development, the influence of ageing and modulation by conformal treatment

Throughout history, cancer has been one of the major causes of death. It has been estimated that in the western world approximately one in three people will develop some kind of cancer during their lifetime, and one in five will die of it. Longevity is associated with prolonged exposure of somatic cells to environmental carcinogens leading to carcinogenesis in these ageing cells. Therefore, cancer is predominantly a disease related to old age. In The Netherlands, the number of persons over 85 years of age increased from 99.000 in 1976 to 203.000 in 1995 (an increase of 1O5 %). It is predicted that by the year 2015 the total population living in The Netherlands will have increased by 8.4%, from 15.4 million in 1994 to 16.7 million. However the proportion of the population more than 65 years of age is expected to grow much faster (45%), although the proportion of persons of 85 years and older will remain the same. In view of the demographic developments, the number of cancer cases can be expected to increase dramatically in the near future. Compared to 1994, for 2015 an increase varying from 30-60 % for cancer of the colon, prostate and breast has been predicted

Business Ownership and Unemployment in Japan

The influence of industrial structure, more specifically of business ownership, is investigated on the level of unemployment in Japan. The question is to what extent business ownership, i.e., entrepreneurship, can reduce the level of unemployment. It will be concluded that Japan is hardly an outlier when using a simple model of the relationship between unemployment and the rate of business ownership. The model is calibrated using recent data of 23 OECD countries. It shows a minor underestimation of the rise in unemployment in Japan in the period 1984-2002. Arguments are brought forward why this might be the case. We argue that small firms in Japan have benefitted in the past from the protective environment of the keiretsu structure. In the current process of industrial restructuring, keiretsu support is dissipating, but has not yet been adequatly replaced with a market environment conducive to the establishment and growth of entrepreneurial firms. The underestimation of the rise in unemployment is a reflection of the limited access of small firms to the market in Japan

The ties that bind: Connections, patterns, and possibilities for marine protected areas

The purpose of this doctoral research is to characterize and assess how social networks enhance and inhibit the governance of marine protected areas (MPAs). Specifically, I examine the structure and function of multiple networks between social actors to better understand their role in the governance of MPAs, and to address a gap in our understanding of how formal and informal rules, rule-making systems, and actor networks contribute to different MPA outcomes. A focus on the social dimensions of MPAs is critical, as they have emerged as a significant marine conservation and climate change adaptation strategy with substantial implications for coastal communities. The research pursues three specific research objectives: (1) to conceptually develop and illustrate the utility of a social relational network perspective for policy-relevant MPA science; (2) to identify and describe how social networks support and constrain transitions to co-management of small-scale fisheries and MPAs; and (3) to examine how social connectivity among actors affiliated with a MPA network can enhance and inhibit governance fit. Formal and informal social networks have been repeatedly cited as a key attribute of multi-actor governance arrangements (e.g., co-managed MPAs) in the broader natural resource management literature. Similarly, the role of social networks has been identified as one of the research frontiers for policy-relevant MPA science. However, not all networks are structurally equal with research suggesting that different patterns of social relations contribute to different management and governance outcomes. Accordingly, understanding how social networks influence outcomes of MPAs is a key research area that has been understudied. A synthetic review was first conducted to outline the emergence and benefit of applying a structurally explicit, social relational network perspective to inform the establishment and governance of MPAs and MPA networks. This social relational network perspective was then used to gain key insights regarding the role of networks for the governance of MPAs and MPA networks based on two empirical cases in Jamaica. The first was a comparative study focused on three Special Fishery Conservation Areas (SFCAs) – i.e., marine no-take areas – and focused on ties between individual fishermen and wardens. The second case examined the actors associated with the national network of Special Fishery Conservation Areas – of which there are fourteen in total – and thus focused on ties between organizations from across the island that contribute to the governance of the SFCAs. Data were collected via a social relational survey (n = 380), semi-structured interviews (n = 63), an organizational network survey (n = 18), focus groups (n = 10), literature and document review, and participant observations. Social network analysis was coupled with qualitative content analysis to assess how patterns of relational ties and interactions between social actors enhance and inhibit the governance of MPAs. This thesis conceptually develops and empirically illustrates the insights and contributions to be gained from taking a social relational network perspective to examine MPA governance, including how such an approach can be applied at different scales (e.g., community level interactions, organizational interactions) and to understand different aspects and issues (e.g., transitions to co-management, governance fit). The second contribution of this study is to illustrate the utility of a social relational network perspective to examine and understand key governance attributes previously identified in the literature – specifically community cohesion and leadership. The third contribution of this study concerns the re-orientation of thinking about MPA networks from a purely ecological and biophysical perspective towards a greater emphasis on social connectivity. A re-orientation towards the consideration of social connectivity among actors associated with a MPA network contributed to preliminary insights concerning how the structure and function of governance networks may enhance and inhibit mismatches (i.e., spatial, temporal, functional) that plague individual MPAs. While the findings presented here are based on research in Jamaica, they are germane to a wide range of contexts given the global expansion of MPAs and MPA networks where similar social relational challenges and opportunities are bound to occur

Neoadjuvant radiotherapy of primary irresectable unicentric Castleman's disease: a case report and review of the literature

<p>Abstract</p> <p>Background</p> <p>Castleman disease (CD) is a rare benign disorder characterised by hyperplasia of lymphoid tissue that may develop at a single site or throughout the body. The etiology of this disorder is unclear, although the histopathological presentation can be differentiated into a hyaline vascular variant, a plasma cell variant and a mixed variant. Clinically, it has been recorded that 3 manifestations of CD are characterized: a localized unicentric type, a generalized multicentric type and a mixed form. Surgery remains the main treatment for resectable unicentric CD, since removal of the large node is possible without further complications. No consensus has been reached concerning the most adequate treatment for irresectable unicentric CD.</p> <p>Methods</p> <p>Case report of a 67 year old woman.</p> <p>Results</p> <p>This report, describes the case of a 67-year-old woman with unicentric Castleman disease located in the right lower abdomen. The patient had symptoms of fatigue, dyspnoea and pain in the right lower abdomen. Computed tomography (CT)- examination revealed a tumour, which had grown to form a close relationship with the common iliac vessels and the sacral bone. A Laparotomy procedure revealed that the tumour was an irresectable mass. Neo-adjuvant radiotherapy (40 Gy) was administered in order to downsize the tumour. Six weeks later a new CT-scan revealed a major reduction of the tumour, which enabled a successful radical resection of the tumour to be performed. Histopathological analysis of the tumour showed the hyaline vascular type of CD.</p> <p>Conclusions</p> <p>Neo-adjuvant radiotherapy should be considered in case of an irresectable unicentric CD.</p

Topology of six degrees of freedom magnetic bearing

A novel magnetic topology has been designed for a six degrees of freedom, magnetically levitated and driven mirror, to be used in a three dimensional (3D) measurement system based on laser interferometry. The translations of the mirror are to be kept small, whereas the rotations are to be controlled over a large range with a high bandwidth and high accuracy. Finite element modelling (FEM) is used to analyze the proposed topology. For computational load reduction, a 2D FEM model has been derived from the actual 3D topology, which incorporates most of the magnetic subsystems. Simulations show that cross-influence between the actuators is small, that the forces and torques are proportional to the applied currents and that the angle of the rotor is of little influence. This allows the multiple in multiple out system to be regarded as multiple linear single in single out systems. ©2000 American Institute of Physics

Effect of Zeolitic Imidazolate Framework Topology on the Purification of Hydrogen from Coke Oven Gas

This work aims to shed light on the performance of zeolitic imidazolate frameworks for hydrogen purification from coke oven gases (COG). Using molecular simulation, we model COG as a mixture of six gases and study the effect of ZIF topology on the separation performance. To do this, we compare similar structures, e.g., ZIF-8 and ZIF-11, and focus on obtaining information that explains why they behave differently while being so similar. Simulation results show that the structure with the smallest pore size best separates hydrogen from carbon monoxide and nonpolar molecules. The adsorption of carbon dioxide is also strongly affected by the polarizability of the structure. However, the adsorption of the other components (methane, carbon monoxide, nitrogen, and oxygen) is strongly dependent on their pore size. We also provide molecular information on the effect of phase transition on hydrogen purification using ZIF-7 as an example, which drastically changes the pore volume of the structure when it changes phase. These findings will help to select high-performance ZIFs for adsorption- or screening-based hydrogen purification.</p