Championing urban farmers in Kampala. Influences on local policy change in Uganda. Process and partnership for pro-poor policy change

This working paper presents an analysis of actors, events and influences affecting a policy change on urban agriculture in Kampala. It reviews the policy and institutional changes related to urban agriculture that occurred in Kampala from 1990 to 2006, and examines how and why they came about. The approach used here combined elements of three established methodologies, viz, episode studies; case study analysis; and outcome mapping. For this case study, the episode study component was central, with the case study and outcome mapping components used to cross-check and deepen the analysis. This information was assembled into three overlapping narratives: 1. A timeline of activities that played a role in changing attitudes and behaviour towards urban agriculture. 2. An analysis of the development of policies affecting urban agriculture in Kampala including the new ordinances. 3. A description of behaviour change of key actors related to the policy change These were summarised in a visual representation of the process and influences and analysed using a framework emphasising political context and the roles of evidence, linkages and external environment

The structure of the PapD-PapGII pilin complex reveals an open and flexible P5 pocket

P pili are hairlike polymeric structures that mediate binding of uropathogenic Escherichia coli to the surface of the kidney via the PapG adhesin at their tips. PapG is composed of two domains: a lectin domain at the tip of the pilus followed by a pilin domain that comprises the initial polymerizing subunit of the 1,000-plus-subunit heteropolymeric pilus fiber. Prior to assembly, periplasmic pilin domains bind to a chaperone, PapD. PapD mediates donor strand complementation, in which a beta strand of PapD temporarily completes the pilin domain's fold, preventing premature, nonproductive interactions with other pilin subunits and facilitating subunit folding. Chaperone-subunit complexes are delivered to the outer membrane usher where donor strand exchange (DSE) replaces PapD's donated beta strand with an amino-terminal extension on the next incoming pilin subunit. This occurs via a zip-in-zip-out mechanism that initiates at a relatively accessible hydrophobic space termed the P5 pocket on the terminally incorporated pilus subunit. Here, we solve the structure of PapD in complex with the pilin domain of isoform II of PapG (PapGIIp). Our data revealed that PapGIIp adopts an immunoglobulin fold with a missing seventh strand, complemented in parallel by the G1 PapD strand, typical of pilin subunits. Comparisons with other chaperone-pilin complexes indicated that the interactive surfaces are highly conserved. Interestingly, the PapGIIp P5 pocket was in an open conformation, which, as molecular dynamics simulations revealed, switches between an open and a closed conformation due to the flexibility of the surrounding loops. Our study reveals the structural details of the DSE mechanism

AN ALTERNATIVE METHOD TO THAT OF THE R6 PROCEDURE FOR THE TREATMENT OF COMBINED PRIMARY AND SECONDARY LOADING

ABSTRACT An alternative definition for the assessment point parameter of the R6 defect assessment procedure is proposed, for combined primary and secondary loading. This alternative definition removes the requirement to calculate a plasticity correction factor for secondary stresses, ρ (or V), used in the conventional R6 definition of . To compare these definitions, both the R6 procedure and the alternative method are presented as Crack Driving Force (CDF) estimation schemes. The required inputs to these estimation schemes have been determined from finite element analyses, for the particular case, of a thick-walled cylinder with a fully circumferential internal defect and subjected to internal pressure and a radial through-wall temperature gradient. Comparisons of CDF estimates with those determined from full inelastic finite element analyses have shown, for the cases studied, that both the R6 and alternative approaches provide conservative estimates of CDF compared to those obtained from finite element analyses, with the degree of conservatism far greater for the conventional R6 approach. Further finite element validation with different geometries, loadings and material properties is required before the alternative procedure could be considered for inclusion in the R6 defect assessment procedure as an alternative to the procedure of the main section of the document

Dietary factors impact on the association between CTSS variants and obesity related traits.

Cathepsin S, a protein coded by the CTSS gene, is implicated in adipose tissue biology--this protein enhances adipose tissue development. Our hypothesis is that common variants in CTSS play a role in body weight regulation and in the development of obesity and that these effects are influenced by dietary factors--increased by high protein, glycemic index and energy diets

Genetically manipulated phages with improved pH resistance for oral administration in veterinary medicine

Orally administered phages to control zoonotic pathogens face important challenges, mainly related to the hostile conditions found in the gastrointestinal tract (GIT). These include temperature, salinity and primarily pH, which is exceptionally low in certain compartments. Phage survival under these conditions can be jeopardized and undermine treatment. Strategies like encapsulation have been attempted with relative success, but are typically complex and require several optimization steps. Here we report a simple and efficient alternative, consisting in the genetic engineering of phages to display lipids on their surfaces. Escherichia coli phage T7 was used as a model and the E. coli PhoE signal peptide was genetically fused to its major capsid protein (10A), enabling phospholipid attachment to the phage capsid. The presence of phospholipids on the mutant phages was confirmed by High Performance Thin Layer Chromatography, Dynamic Light Scattering and phospholipase assays. The stability of phages was analysed in simulated GIT conditions, demonstrating improved stability of the mutant phages with survival rates 102107 pfu.mL1 higher than wild-type phages. Our work demonstrates that phage engineering can be a good strategy to improve phage tolerance to GIT conditions, having promising application for oral administration in veterinary medicine.This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and under the scope of the Project PTDC/BBB-BSS/6471/2014 (POCI-01-0145-FEDER-016678). Franklin L. Nobrega and Ana Rita Costa acknowledge FCT for grants SFRH/BD/86462/2012 and SFRH/BPD/94648/2013, respectively. Melvin F. Siliakus acknowledges funding from the Biobased Ecologically Balanced Sustainable Industrial Chemistry (BE-BASIC) foundation. Electron microscopy work was performed at the Wageningen Electron Microscopy Centre (WEMC) of Wageningen University

TESS and CHEOPS discover two warm sub-Neptunes transiting the bright K-dwarf HD 15906

We report the discovery of two warm sub-Neptunes transiting the bright (G = 9.5 mag) K-dwarf HD 15906 (TOI 461, TIC 4646810). This star was observed by the Transiting Exoplanet Survey Satellite (TESS) in sectors 4 and 31, revealing two small transiting planets. The inner planet, HD 15906 b, was detected with an unambiguous period but the outer planet, HD 15906 c, showed only two transits separated by ∼ 734 d, leading to 36 possible values of its period. We performed follow-up observations with the CHaracterising ExOPlanet Satellite (CHEOPS) to confirm the true period of HD 15906 c and improve the radius precision of the two planets. From TESS, CHEOPS, and additional ground-based photometry, we find that HD 15906 b has a radius of 2.24 ± 0.08 R⊕ and a period of 10.924709 ± 0.000032 d, whilst HD 15906 c has a radius of 2.93+0.07−0.06 R⊕ and a period of 21.583298+0.000052−0.000055 d. Assuming zero bond albedo and full day-night heat redistribution, the inner and outer planet have equilibrium temperatures of 668 ± 13 K and 532 ± 10 K, respectively. The HD 15906 system has become one of only six multiplanet systems with two warm (≲ 700 K) sub-Neptune sized planets transiting a bright star (G ≤ 10 mag). It is an excellent target for detailed characterization studies to constrain the composition of sub-Neptune planets and test theories of planet formation and evolution

The atmosphere and architecture of WASP-189 b probed by its CHEOPS phase curve

Context. Gas giants orbiting close to hot and massive early-type stars can reach dayside temperatures that are comparable to those of the coldest stars. These ‘ultra-hot Jupiters’ have atmospheres made of ions and atomic species from molecular dissociation and feature strong day-to-night temperature gradients. Photometric observations at different orbital phases provide insights on the planet’s atmospheric properties. Aims. We aim to analyse the photometric observations of WASP-189 acquired with the Characterising Exoplanet Satellite (CHEOPS) to derive constraints on the system architecture and the planetary atmosphere. Methods. We implemented a light-curve model suited for an asymmetric transit shape caused by the gravity-darkened photosphere of the fast-rotating host star. We also modelled the reflective and thermal components of the planetary flux, the effect of stellar oblateness and light-travel time on transit-eclipse timings, the stellar activity, and CHEOPS systematics. Results. From the asymmetric transit, we measure the size of the ultra-hot Jupiter WASP-189 b, Rp = 1.600−0.016+0.017 RJ, with a precision of 1%, and the true orbital obliquity of the planetary system, Ψp = 89.6 ± 1.2deg (polar orbit). We detect no significant hotspot offset from the phase curve and obtain an eclipse depth of δecl = 96.5−5.0+4.5 ppm, from which we derive an upper limit on the geometric albedo: Ag < 0.48. We also find that the eclipse depth can only be explained by thermal emission alone in the case of extremely inefficient energy redistribution. Finally, we attribute the photometric variability to the stellar rotation, either through superficial inhomogeneities or resonance couplings between the convective core and the radiative envelope. Conclusions. Based on the derived system architecture, we predict the eclipse depth in the upcoming Transiting Exoplanet Survey Satellite (TESS) observations to be up to ~165 ppm. High-precision detection of the eclipse in both CHEOPS and TESS passbands might help disentangle reflective and thermal contributions. We also expect the right ascension of the ascending node of the orbit to precess due to the perturbations induced by the stellar quadrupole moment J2 (oblateness)

Condition Monitoring and Diagnostic Assessment of Transformers

Condition monitoring and diagnostic assessment of transformers is a useful tool for managing power networks. When managing a large fleet of ageing transformers, asset managers have to be more innovative to integrate the data from a variety of condition monitoring systems into the decision-making process. Collective research efforts on this topic were made by a transformer research consortium in the United Kingdom. This paper provides an overview of the research in the following three aspects: analysis of large oil databases from field transformers, detection of methanol in oil as an advanced paper ageing indicator and transformer thermal modelling using computational fluid dynamic (CFD).Observations from oil database analysis included a generic early degradation phenomenon, testing frequency of the common parameters, correlation of these parameters with transformer age as well as data interpretation in terms of incorporation of sampling temperature and potential revision to standardised values. Laboratory ageing experiments confirmed the suitability of methanol as a potential early paper ageing indicator in both an inhibited conventional mineral oil and a new inhibited gas-to-liquid hydrocarbon based oil. Measurements of methanol for UK field transformers showed a general increasing trend with ageing. Oil flow distribution in the windings has a direct impact on the cooling performance. CFD simulations and dimensional analysis were performed to study the occurrence of reverse flow in the winding. It was found that a higher oil flow rate does not necessarily mean a better cooling performance

Effect of sonication on the reactivity of silica fume in portland cement mortars

Permission is granted by ICE Publishing to print one copy for personal use. Any other use of these PDF files is subject to reprint fees.Currently, the use of silica fume for the production of mortars and high-performance concrete is of great importance to the construction materials sector. Different applications of silica fume have generated extensive studies about its high reactivity as a pozzolanic material, in addition to its effect on the properties of some materials within which it is incorporated. In this study a sonication process was applied by means of which the deagglomeration of the larger particles of densi¿ed silica fume (CSF) was achieved. The result is a CSF treated with the ultrasound probe, which is obtained for different tests where the parameters of sonication such as sonication power level and sonication time are varied. This treatment makes it possible to increase the quantity of submicrometric particles in the sample. The effect of sonication process on CSF produces a greater quantity of very ¿ne particles, which improve the pozzolanic reactivity of silica fume and increase the ¿xation of hydrated lime. This behaviour also produces higher mechanical strength in mortars manufactured with sonicated silica fume (SSF). The mechanical strengths of SSF mortars were greater than those for control and CSF mortar. Different percentages of cement were substituted (between 0 and 15% by weight), and in all cases the SSF mortars showed important differences from the CSF mortar. It was observed that for the longest sonication times and highest sonication power levels, mechanical strengths were increased.The authors are grateful to the Spanish company Ferroatlantica S.L. for their financial support; to the Spanish Agency of International Cooperation and Development (AECID) for the doctorate grant to D.M.-V.; to the Spanish government for their support to the project BIA 2007-63252; and to FEDER for its financial support to our research projects.Martínez Velandia, DA.; Paya Bernabeu, JJ.; Monzó Balbuena, JM.; Borrachero Rosado, MV. (2011). Effect of sonication on the reactivity of silica fume in portland cement mortars. Advances in Cement Research. (1):23-31. https://doi.org/10.1680/adcr.8.00027S2331