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Purpose: Phosphorus saturation-transfer experiments can quantify metabolic fluxes non-invasively. Typically, the forward flux through the creatine-kinase reaction is investigated by observing the decrease in phosphocreatine (PCr) after saturation of $\gamma$-ATP. The quantification of total ATP utilisation is currently under-explored, as it requires simultaneous saturation of inorganic phosphate (Pi) and PCr. This is challenging, as currently available saturation pulses reduce the already-low $\gamma$-ATP signal present. Methods: Using a hybrid optimal-control and Shinnar-Le-Roux method, a quasi-adiabatic RF pulse was designed for the dual-saturation of PCr and Pi to enable determination of total ATP utilisation. The pulses were evaluated in Bloch equation simulations, compared with a conventional hard-cosine DANTE saturation sequence, before application to perfused rat hearts at 11.7 Tesla. Results: The quasi-adiabatic pulse was insensitive to a $>2.5$-fold variation in $B_1$, producing equivalent saturation with a 53% reduction in delivered pulse power and a 33-fold reduction in spillover at the minimum effective $B_1$. This enabled the complete quantification of the synthesis and degradation fluxes for ATP in 30-45 minutes in the perfused rat heart. While the net synthesis flux ($4.24\pm0.8$ mM/s, SEM) was not significantly different from degradation flux ($6.88\pm2$ mM/s, $p=0.06$) and both measures are consistent with prior work, nonlinear error analysis highlights uncertainties in the Pi-to-ATP measurement that may explain a trend suggesting a possible imbalance. Conclusion: This work demonstrates a novel quasi-adiabatic dual-saturation RF pulse with significantly improved performance that can be used to measure ATP turnover in the heart in vivo., Comment: 26 pages, Accepted at Magnetic Resonance in Medicine, 24/11/2020 [This version post reviews]

The use of cash transfer programmes in humanitarian contexts is growing. In comparison to in-kind assistance, cash transfers are widely praised for enhancing autonomy, reducing costs, and boosting local markets. A recurring question in the literature on cash transfers is whether the use of transfers should be restricted to food and other essential items and exclude temptation goods such as alcohol or tobacco. We use first-hand data from 896 refugee households living in the recently created Kalobeyei settlement in Kenya, making use of a ‘natural experiment’ to study the relative effects of restricted versus unrestricted cash transfers to refugees. Our research shows that removing restrictions on cash transfers has positive impacts on asset holding and subjective well-being. Households receiving unrestricted cash transfers are also less likely to engage in the costly practice of reselling food in order to access non-food items. We find some evidence that unrestricted transfers may lead to higher expenditure on alcohol and tobacco. Although this is worrying, it relates to only a limited proportion of households and a small proportion of their budget. But both modalities of cash-based assistance are associated with a massive problem of indebtedness, which undermines their effectiveness. A staggering 89% of sampled households are indebted towards their retailers. Cash transfers are used as a form of collateral by retailers to guarantee debt repayment. We discuss the pros and cons of various policy options for addressing the problem of indebtedness, including debt repayment schemes or debt relief, social safety nets, more frequent transfers, training, and monitoring.

Environmental restoration and conservation challenges go beyond what can be financed publicly. There are significant opportunities for private investment in the delivery of public goods, benefitting both commercial organisations whose business relies on ecosystem services, as well as landowners, land managers and the general public. Thus, public-private financing of natural capital improvement presents an opportunity to increase the availability of funding for payments for ecosystem services that provide environmental and societal benefits. Though public-private partnerships for the financing of ecosystem services is in its infancy in the UK. This new report explores the voluntary ecosystem services market in the UK. This is achieved by developing an understanding of how key actors (schemes, stakeholder engagement initiatives, trading platforms and supporting modelling tools) operate, and by identifying possible synergies, examples of good practice and challenges to implementation. Topics covered include, understanding how the identified actors account for the social distribution of ecosystem services, how values are attributed to ecosystem services, and the legal obligations linked to ventures’ operation.

Purpose Phosphorus magnetic resonance spectroscopy (31P‐MRS) provides a unique tool for assessing cardiac energy metabolism, often quantified using the phosphocreatine (PCr)/adenosine triphosphate (ATP) ratio. Surface coils are typically used for excitation for 31P‐MRS, but they create an inhomogeneous excitation field across the myocardium, producing undesirable, spatially varying partial saturation. Therefore, we implemented adiabatic excitation in a 3D chemical shift imaging (CSI) sequence for cardiac 31P‐MRS at 7 Tesla (T). Methods We optimized an adiabatic half passage pulse with bandwidth sufficient to excite PCr and γ‐ATP together. In addition, the CSI sequence was modified to allow interleaved excitation of PCr and γ‐ATP, then 2,3‐DPG, to enable PCr/ATP determination with blood correction. Nine volunteers were scanned at 2 transmit voltages to confirm that measured PCr/ATP was independent of B1+ (i.e. over the adiabatic threshold). Six septal voxels were evaluated for each volunteer. Results Phantom experiments showed that adiabatic excitation can be reached at the depth of the heart using our pulse. The mean evaluated cardiac PCr/ATP ratio from all 9 volunteers corrected for blood signal was 2.14 ± 0.16. Comparing the two acquisitions with different voltages resulted in a minimal mean difference of −0.005. Conclusion Adiabatic excitation is possible in the human heart at 7 T, and gives consistent PCr/ATP ratios. Magn Reson Med 78:1667–1673, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

This report draws upon a business survey with food retailers to assess the impact of the ‘Bamba Chakula’ model of electronic food transfers and business contracts. The Kakuma refugee camps have become popularly associated with entrepreneurship. In 2016, the Kalobeyei settlement was opened 3.5 kms away from the Kakuma camps, with the intention of promoting the self-reliance of refugees and the host population, and delivering integrated services to both. Its development is guided by the Kalobeyei Integrated Social and Economic Development Programme (KISEDP), which offers a range of innovative, market-based approaches to refugee protection that diverge from the conventional aid model implemented in Kakuma. There have been few studies that examine the emergence of refugee-led markets at the business level, whether in the Kakuma camps, in the Kalobeyei settlement, or elsewhere. In order to address this gap, our research aimed to study one particular sector: the food market. This sector is of particular interest because it is such a significant part of economic life in refugee camps, and because it is heavily shaped by the modalities of food assistance provided by the international community. Kakuma is currently undergoing a gradual transition from in-kind food assistance to cash-based assistance, and as an interim step, it has introduced a food provision model called Bamba Chakula.

This report outlines a conceptual model and indicators for measuring refugee self-reliance, and applies it to the Kalobeyei settlement and Kakuma refugee camps context. The Kalobeyei settlement was opened in Turkana County in Kenya in 2016 with the intention of promoting the self-reliance of refugees and the host population and delivering integrated services to both. Its development is now guided by the Kalobeyei Integrated Social and Economic Development Programme (KISEDP), led by the Government of Kenya (GoK), the Turkana County Government, UNHCR, and partners. KISEDP envisions a range of innovative, market-based approaches to refugee protection that diverge from the conventional aid model implemented in Kakuma. These include cash-based programmes to meet housing, nutritional and other material needs, training to capitalise on the skills and entrepreneurial potential of refugees and hosts, and agricultural projects to promote dryland farming and household ‘kitchen gardens’. This report is based upon a 3-year study following newly arrived refugees integrated into the new Kalobeyei settlement and the old Kakuma refugee camp since 2016. The newly arrived refugees were allocated between the two contexts based on their date of arrival. In the study, we follow newly arrived South Sudanese refugee in both Kalobeyei and Kakuma in order to compare outcomes over time, and identify what difference the Kalobeyei settlement makes in comparison to the Kakuma model. We also follow newly arrived Ethiopian and Burundian refugees within Kalobeyei. The report covers two waves of data collection with the same randomly sampled respondent population, carried out in 2017 and 2018.

In places formerly characterised by the economic and political predominance of mobile pastoralists, the rise of urban centres can dramatically alter the social landscape, with both positive and negative consequences for herders. While many studies describe the processes (e.g. sedentarisation and commercialisation) affecting pastoralism as a livelihood system, there are fewer accounts of the divisions that emerge when these effects are unequally experienced by different people within that system. Through an ethnography of development- induced social differentiation in Turkana, Kenya, this study examines the ways that herders perceive, make sense of, and respond to their changing circumstances. Many herders in contemporary Turkana refer to themselves as raiya, a word derived from the Swahili term for ‘civilian’ or ‘subject’ but reworked through historical encounters between rural Turkana-speaking communities and various agents of “development”, including missionaries, international agencies, and the state. This term takes on different connotations for differently-positioned speakers: Formally educated urbanites describe the raiya as rural people who “lack” education, development, and global awareness, while rural herders use the term with pride to describe their toughness, pastoral knowledge, and adherence to customary practices (ng’italio). To explore the meaning of raiya – as both an exonym applied by urban dwellers and an endonym adopted by the rural periphery – and its implications for social stratification, I conducted 18 months of fieldwork between 2015 and 2016 along a rural-to- urban transect. Using the concept of the cultural archive (James 1988), I discuss how herders draw on notions from an idealised nomadic past to distinguish themselves as raiya. This is manifested in explicit descriptions of “tradition” (etal), but also in everyday performances of style, skilled livelihood practices, and attunement to the remote landscapes in the borderlands where they live. However, while the notion of raiya makes explicit reference to conventional binaries – distinguishing rural/traditional/non-literate herders from their urban/modern/educated counterparts – I argue that the flexibility of its more implicit meanings has made it useful in negotiating relationships across these dichotomies. This is especially important as herders manage kinship obligations and political relations with educated elites. The future prospects for herders in Turkana are not a matter of their persistence as pastoralists or their adherence to conservative tradition, but the particular ways that they re-articulate kinship and political relations with elites, who are increasingly untethered from the pastoralist moral economy as urban opportunities reduce their reliance on the family herd.

Background Cardiac remodeling, after a myocardial insult, often causes progression to heart failure. The relationship between alterations in left ventricular blood flow, including kinetic energy (KE), and remodeling is uncertain. We hypothesized that increasing derangements in left ventricular blood flow would relate to (1) conventional cardiac remodeling markers, (2) increased levels of biochemical remodeling markers, (3) altered cardiac energetics, and (4) worsening patient symptoms and functional capacity. Methods Thirty-four dilated cardiomyopathy patients, 30 ischemic cardiomyopathy patients, and 36 controls underwent magnetic resonance including 4-dimensional flow, BNP (brain-type natriuretic peptide) measurement, functional capacity assessment (6-minute walk test), and symptom quantification. A subgroup of dilated cardiomyopathy and control subjects underwent cardiac energetic assessment. Left ventricular flow was separated into 4 components: direct flow, retained inflow, delayed ejection flow, and residual volume. Average KE throughout the cardiac cycle was calculated. Results Patients had reduced direct flow proportion and direct-flow average KE compared with controls (PPP=0.019) and direct-flow average KE (β=0.280,P=0.035; R2model, 0.466,P=0.002). In contrast, neither ejection fraction nor left ventricular volumes were independently predictive. Conclusions This study demonstrates an independent predictive relationship between the direct-flow average KE and a prognostic measure of functional capacity. Intracardiac 4-dimensional flow parameters are novel biomarkers in heart failure and may provide additive value in monitoring new therapies and predicting prognosis.

Purpose: We test the reproducibility of human cardiac phosphorus MRS (31P‐MRS) at ultra‐high field strength (7 T) for the first time. The primary motivation of this work was to assess the reproducibility of a ‘rapid’ 6½ min 31P three‐dimensional chemical shift imaging (3D‐CSI) sequence, which if sufficiently reproducible would allow the study of stress‐response processes. We compare this with an established 28 min protocol, designed to record high‐quality spectra in a clinically feasible scan time. Finally, we use this opportunity to compare the effect of per‐subject B0 shimming on data quality and reproducibility in the 6½ min protocol. Methods: 10 healthy subjects were scanned on two occasions: one to test the 28 min 3D‐CSI protocol, and one to test the 6½ min protocol. Spectra were fitted using the OXSA MATLAB toolbox. The phosphocreatine to adenosine triphosphate concentration ratio (PCr/ATP) from each scan was analysed for intra‐ and intersubject variability. The impact of different strategies for voxel selection was assessed. Results: There were no significant differences between repeated measurements in the same subject. For the 28 min protocol, PCr/ATP in the midseptal voxel across all scans was 1.91 ± 0.36 (mean ± intersubject SD). For the 6½ min protocol, PCr/ATP in the midseptal voxel was 1.76 ± 0.40. The coefficients of reproducibility (CRs) were 0.49 (28 min) and 0.67 (6½ min). Per‐subject B0 shimming improved the fitted PCr/ATP precision (for 6½ min scans), but had negligible effect on the CR (0.67 versus 0.66). Conclusions: Both 7 T protocols show improved reproducibility compared with a previous 3 T study by Tyler et al. Our results will enable informed power calculations and protocol selection for future clinical research studies.