79,021 research outputs found

    The Partnership Paperchase: Structuring Partnership Agreements in Water and Sanitation in Low-income Communities

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    Tripartite partnerships between water utilities, local government and civil society are often seen as a good way to deliver services to informal urban communities and slums. However, while these 'partnerships' can be seen as benign relationships, they often fail because the incentives and interests of the partners are not well aligned. In this report, the authors argue that the development of robust documentation (in forms which consitute a 'contractual' agreement) can enhance the performance of such partnerships. Aspects of the partnership which should be included in such documentation include roles and responsibilities, financing, objectives and indicators of success and dispute-resolution mechanisms. The report provides practical guidance and examples of good practice to guide the reader through a process of developing such documentation

    The Partnership Paperchase: Structuring Partnership Agreements in Water and Sanitation in Low-income Communities

    No full text
    Tripartite partnerships between water utilities, local government and civil society are often seen as a good way to deliver services to informal urban communities and slums. However, while these 'partnerships' can be seen as benign relationships, they often fail because the incentives and interests of the partners are not well aligned. In this report, the authors argue that the development of robust documentation (in forms which consitute a 'contractual' agreement) can enhance the performance of such partnerships. Aspects of the partnership which should be included in such documentation include roles and responsibilities, financing, objectives and indicators of success and dispute-resolution mechanisms. The report provides practical guidance and examples of good practice to guide the reader through a process of developing such documentation

    Optical and electrical activity of defects in rare earth implanted Si

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    A common technique for introducing rare earth atoms into Si and related materials for photonic applications is ion implantation. It is compatible with standard Si processing, and also allows high, non-equilibrium concentrations of rare earths to be introduced. However, the high energies often employed mean that there are collision cascades and potentially severe end-of-range damage. This paper reports on studies of this damage, and the competition it may present to the optical activity of the rare earths. Er-, Si, and Yb-implanted Si samples have been investigated, before and after anneals designed to restore the sample crystallinity. The electrical activity of defects in as-implanted Er, Si, and Yb doped Si has been studied by Deep Level Transient Spectroscopy (DTLS) and the related, high resolution technique, Laplace DLTS (LDLTS), as a function of annealing. Er-implanted Si, regrown by solid phase epitaxy at 600degrees C and then subject to a rapid thermal anneal, has also been studied by time-resolved photoluminescence (PL). The LDLTS studies reveal that there are clear differences in the defect population as a function of depth from the surface, and this is attributed to different defects in the vacancy-rich and interstitial-rich regions. Defects in the interstitial-rich region have electrical characteristics typical of small extended defects, and these may provide the precursors for larger structural defects in annealed layers. The time-resolved PL of the annealed layers, in combination with electron microscopy, shows that the Er emission at 1.54microns contains a fast component attributed to non-radiative recombination at deep states due to small dislocations. It is concluded that there can be measurable competition to the radiative efficiency in rare-earth implanted Si that is due to the implantation and is not specific to Er.</p

    Numerical Evidence for Divergent Burnett Coefficients

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    In previous papers [Phys. Rev. A {\bf 41}, 4501 (1990), Phys. Rev. E {\bf 18}, 3178 (1993)], simple equilibrium expressions were obtained for nonlinear Burnett coefficients. A preliminary calculation of a 32 particle Lennard-Jones fluid was presented in the previous paper. Now, sufficient resources have become available to address the question of whether nonlinear Burnett coefficients are finite for soft spheres. The hard sphere case is known to have infinite nonlinear Burnett coefficients (ie a nonanalytic constitutive relation) from mode coupling theory. This paper reports a molecular dynamics caclulation of the third order nonlinear Burnett coefficient of a Lennard-Jones fluid undergoing colour flow, which indicates that this term is diverges in the thermodynamic limit.Comment: 12 pages, 9 figure

    Is the Water Sector Lagging behind Education and Health on Aid Effectiveness? Lessons from Bangladesh, Ethiopia and Uganda

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    A study in three countries (Bangladesh, Ethiopia and Uganda) assessed progress against the Paris Principles for Aid Effectiveness (AE) in three sectors – water, health and education – to test the assumption that the water sector is lagging behind. The findings show that it is too simplistic to say that the water sector is lagging, although this may well be the case in some countries. The study found that wider governance issues are more important for AE than having in place sector-specific mechanics such as Sector-Wide Approaches alone. National political leadership and governance are central drivers of sector AE, while national financial and procurement systems and the behaviour of actors who have not signed up to the Paris Principles – at both national and global levels – have implications for progress that cut across sectors. Sectors and sub-sectors do nonetheless have distinct features that must be considered in attempting to improve sector-level AE. In light of these findings, using political economy approaches to better understand and address governance and strengthening sector-level monitoring is recommended as part of efforts to improve AE and development results in the water sector

    On the fine structure of medium energy electron fluxes in the auroral zone and related effects in the ionospheric D-region

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    This study is based on measurements of trapped and precipitated electrons of energy &gt;30 keV and &gt;100 keV observed by polar orbiting environmental satellites during overpasses of the imaging riometer at Kilpisjärvi, Finland. The satellites are in sun-synchronous orbits of about 850 km altitude, recording the electron fluxes at 2-s time resolution. The riometer measures the radiowave absorption at 38.2 MHz, showing the spatial pattern within a 240 km field of view. <br><br> The analysis has focussed on two areas. Having found a close correlation between the radiowave absorption and the medium-energy electron fluxes during satellite overpasses, empirical relationships are derived, enabling one quantity to be predicted from the other for three sectors of local time. It is shown that small-scale variations observed during a pass are essentially spatial rather than temporal. <br><br> Other properties, such as the spectra and the relation between precipitated and trapped components, are also considered in the light of the theory of pitch angle scattering by VLF waves. It is found that the properties and behaviour depend strongly on the time of day. In the noon sector, the precipitated and trapped fluxes are highly correlated through a square law relationship

    Matter waves in a gravitational field: An index of refraction for massive particles in general relativity

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    We consider the propagation of massive-particle de Broglie waves in a static, isotropic metric in general relativity. We demonstrate the existence of an index of refraction that governs the waves and that has all the properties of a classical index of refraction. We confirm our interpretation with a WKB solution of the general-relativistic Klein-Gordon equation. Finally, we make some observations on the significance of the optical action.Comment: 20 pages, latex, ps and pdf. To appear in Am.J.Phys September, 200

    Adults’ numeracy practices in fluid and unstable contexts—An agenda for education, policy and research?

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    Numeracy practices are always dependent on the social context in which they emerge. These contexts, however, are unstable because of a range of technological and socio-political changes. How does this instability affect people’s agency in the world? After reviewing key approaches to numeracy practices research, we distil key findings from recent numeracy studies. We introduce the concept of the numerate environment to examine the context in which opportunities, supports and demands present themselves for people’s numeracy development, explaining how cultural-historical activity theory can be used to analyse the effects of changes in numerate environments. We consider examples of social trends likely to effect such changes and conclude with implications of shifts in people’s numerate environment for future educational provision, policy and research

    Engaging men with penile cancer in qualitative research: reflections from an interview-based study.

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    To explore the challenges of engaging men with penile cancer in qualitative interview research

    Interleukin-17 is required for control of chronic lung infection caused by Pseudomonas aeruginosa

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    Chronic pulmonary infection with Pseudomonas aeruginosa is a feature of cystic fibrosis (CF) and other chronic lung diseases. Cytokines of the IL-17 family have been proposed as important in the host response to P. aeruginosa infection through augmenting antibacterial immune responses, although their pro-inflammatory effect may contribute to lung damage that occurs as a result of chronic infection. We set out to explore the role of IL-17 in the host response to chronic P. aeruginosa infection. We used a murine model of chronic pulmonary infection with CF-related strains of P. aeruginosa. We demonstrate that IL-17 cytokine signaling is essential for survival and prevention of chronic infection at 2 weeks post-inoculation using two different P. aeruginosa strains. Following infection, there was a marked expansion of cells within mediastinal lymph nodes, comprised mainly of innate lymphoid cells (ILCs); ∼90% of IL-17 producing cells had markers consistent with Group 3 ILCs. A smaller percentage of IL-17+ cells had markers consistent with a B1 phenotype. In lung homogenates 14 days following infection, there was a significant expansion of IL-17+ cells – about 50% of these were CD3+, split equally between CD4+ Th17 cells and γδ T cells, while the CD3- IL-17+ cells were almost exclusively Group 3 ILCs. Further experiments with B cell deficient mice showed that B cell production of IL-17 or natural antibodies did not provide any defence against chronic P. aeruginosa infection. Thus, IL-17 rather than antibody is a key element in host defence against chronic pulmonary infection with P. aeruginosa
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