Social Capital and Self-rated Health: testing association with longitudinal and multilevel methodologies

Since Durkheim’s seminal work over a century ago, research has repeatedly shown that individuals with higher levels of social integration, social networks and social support have better health status. However, the recent introduction of a contextual phenomenon known as social capital to the field of public health has sparked lively debate as to how it may also influence the health of individuals, if at all. Though critics have raised several points of contention regarding reported association between social capital and health over recent years, one outstanding issue remains: the lack of empirical research focusing on causal relationships, due to paucity of adequate longitudinal social capital data. The overall aim of this thesis is to test association between different social capital proxies and self-rated health (SRH), alongside other well-known health determinants, using multilevel and longitudinal data, whilst employing a variety of study designs and methods. All data used in this thesis come from the United Kingdom’s British Household Panel Survey (BHPS) from years 2000, 03, 05, 07 and 08. The underlying premise of this body of work is to investigate temporal (causal) relationships between social capital and health. All four papers of this thesis demonstrate that generalised trust is the most robust of all social capital proxies tested, it maintaining a positive association with SRH over time. Furthermore, results from paper III imply that prior trust levels can predict future SRH, lending weight to the hypothesis that trust is an independent determinant of health. However, debate remains as to whether generalised trust solely captures social capital or other, more tangible aspects of social cohesion

Charge doping and large lattice expansion in oxygen-deficient heteroepitaxial WO3

Tungsten trioxide is a versatile material with widespread applications ranging from electrochromic and optoelectronic devices to water splitting and catalysis of chemical reactions. For technological applications, thin films of WO3 are particularly appealing, taking advantage from high surface-to-volume ratio and tunable physical properties. However, the growth of stoichiometric, crystalline thin films is challenging because the deposition conditions are very sensitive to the formation of oxygen vacancies. In this work, we show how background oxygen pressure during pulsed laser deposition can be used to tune the structural and electronic properties of WO3 thin films. By performing X-ray diffraction and low-temperature transport measurements, we find changes in WO3 lattice volume up to 10%, concomitantly with an insulator-to-metal transition as a function of increased level of electron doping. We use advanced ab initio calculations to describe in detail the properties of the oxygen vacancy defect states, and their evolution in terms of excess charge concentration. Our results depict an intriguing scenario where structural, electronic, optical, and transport properties of WO3 single-crystal thin films can all be purposely tuned by a suited control of oxygen vacancies formation during growth

Network Traffic Processing with PFQ

This paper presents Packet Family Queue (PFQ), a high-performance framework for packet processing designed to flexibly handle network applications parallelism and making traffic processing safe and easy. PFQ is an open-source module for the Linux kernel that combines software-accelerated packet I/O to in-kernel early stage packet processing and fine-grained distribution to network applications and physical devices. PFQ does not require any modification to network device drivers and exposes programming interfaces to multi-threaded applications natively designed to run on top of it, as well as to legacy monitoring tools using the pcap library. The results show that the flexibility and the backward compatibility provided by PFQ do not impact its processing performance that, in fact, reaches line rate figures in the cases of pure speed tests and real practical monitoring use cases on 10+ Gb/s links

Enif-lang: A specialized language for programming network functions on commodity hardware

The maturity level reached by today’s commodity platforms makes even low-cost PCs viable alternatives to dedicated hardware to implement real network functions without sacrificing performance. Indeed, the availability of multi-core processing packages and multi-queue network interfaces that can be managed by accelerated I/O frameworks, provides off-the-shelf servers with the necessary power capability for running a broad variety of network applications with near hardware-class performance. At the same time, the introduction of the Software Defined Networks (SDN) and the Network Functions Virtualization (NFV) paradigms call for new programming abstractions and tools to allow this new class of network devices to be flexibly configured and functionally repurposed from the network control plane. The paper presents the ongoing work towards Enif-Lang (Enhanced Network processIng Functional Language), a functional language for programming network functions over generic middleboxes running the Linux operating system. The language addresses concurrent programming by design and is targeted at developing simple stand-alone applications as well as pre-processing stages of packet elaborations. Enif-Lang is implemented as a Domain Specific Language embedded in the Haskell language and inherits the main principles of its ancestor, including the strong typedness and the concept of function compositions. Complex network functions are implemented by composing a set of elementary operations (primitives) by means of a compact yet expressive language grammar. Throughout the paper, the description of the design principles and features of Enif-Lang are accompanied by examples and use cases. In addition, a preliminary performance assessment is carried out to prove the effectiveness of the language for developing practical applications with the performance level required by 5G systems and the Tactile Internet

The good governance agenda for decentralization in Uttarakhand, India: implications for social justice

367 leaves : ill. ; 29 cm.Includes bibliographical references (leaves 320-331)This thesis explores the link between social justice and decentralization at the theoretical and empirical level. The central argument is that decentralization as prescribed by the good governance agenda has compromised the constitutional guarantees of social justice in India. Initially, the thesis provides a detailed analysis of good governance, comparing the viewpoints of proponents and critics. It is initially analyzed, in detail, from the point of views of its claims and critiques. The implementation of decentralization is discussed in relation to its good governance rationale and principles of social justice. Critiques from various schools of thought shed light on the controversies and potential for change emerging out of the current approach. The empirical analysis is based upon field data collected from eight villages in the Indian state of Uttarakhand. Two types of decentralization policies are examined: Panchayati Raj (village governance) and Van Panchayat (forest governance). Both policies are essential to understand how social justice plays at many levels on the grassroots reality: livelihood, self-governance, participation and market pressures. The final discussion establishes the link between empirical evidence and the central argument along with a possible alternative approach for implementing decentralization, namely the Ghandian model of Village Swaraj

Social capital and self-rated health – a study of temporal (causal) relationships

Despite the vast amount of research over the past fifteen years, there is still lively debate surrounding the role of social capital on individual health outcomes. This seems to stem from a lack of consistency regarding the definition, measurement and plausible theories linking this contextual phenomenon to health. We have further identified a knowledge gap within this field - a distinct lack of research investigating temporal relationships between social capital and health outcomes. To remedy this shortfall, we use four waves of the British Household Panel Survey to follow the same individuals (N = 8114) between years 2000 and 2007. We investigate temporal relationships and association between our outcome variable self-rated health (SRH) and time-lagged explanatory variables, including three individual-level social capital proxies and other well-known health determinants. Our results suggest that levels of the social capital proxy ‘generalised trust’ at time point (t-1) are positively associated with SRH at subsequent time point (t), even after taking into consideration levels of other well-known health determinants (such as smoking status) at time point (t-1). That we investigate temporal relationships at four separate occasions over the seven year period lends considerable weight to our results and the argument that generalised trust is an independent predictor of individual health. However, lack of consensus across a variety of disciplines as to what generalised trust is believed to measure creates ambiguity when attempting to identify possible pathways from higher trust to better health