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A new era of international development aspires to increase the dignity and capabilities of those in poverty. Yet narratives accompanying aid often reinforce stigmatizing views of those in poverty as deficient in their circumstances or ability. We find that typical deficit-focused narratives risk undermining the very goals of aid—to empower recipients to pursue their goals and experience dignity rather than shame. In contrast, narratives crafted to counter stigma and leverage culturally-resonant forms of agency better enhance recipients’ beliefs in themselves and investment in their skills, without reducing donor support. As models of agency differ across sociocultural contexts, program designers need conceptual tools and methods for identifying effective narratives. We present “local forecasting” as a particularly efficient methodology for this need.

AIM To investigate the role of a novel minimally invasive endoscopic technique in the management of tight near-total corrosive strictures of the proximal esophagus involving the hypopharynx. METHODS Two patients with near-total corrosive strictures of the proximal esophagus involving the hypopharynx were managed with the novel endoscopic technique. The technique involved passing a 0.025-inch flexible guide-wire across the stricture, and stricture dilatation, using 10F coaxial diathermy and balloon dilators, followed by electro-incision of the proximal aspect of the residual eccentric stricture by means of a novel approach using a wire-guided sphincterotome. RESULTS Both patients were successfully managed on an outpatient department basis with the complete relief of symptoms and resolution of strictures on endoscopy and an esophagogram. No adverse events were seen during or after the procedure. There was no recurrence of symptoms at a follow-up of over a year in both cases. There was a significant improvement in the body mass index of both patients after the procedure. CONCLUSION We report a novel flexible endoscopic technique for the management of complex hypopharyngo-esophageal strictures. In experienced hands, the procedure is relatively simple, safe and effective with a durable response.

A new software platform to enable the control of large scientific equipment through EPICS has been designed. The system implements a modern tool chain with a React frontend and a PyEpics backend as a progressive web application. This enables efficient and responsive cross platform and cross device operation. A general overview of React Automation Studio as well as the system architecture, implementation at iThemba LABs, community involvement and future plans for the system is presented., Proceedings of the 22nd International Conference on Cyclotrons and their Applications, Cyclotrons2019, Cape Town, South Africa

iThemba Laboratory for Accelerator Based Sciences (iThemba LABS) has, over the past 30 years, carried out several upgrades to its control electronics and software. This culminated in the adoption of EPICS as the de-facto distributed control system at the lab. In order to meet the changing technology and user requirements, iThemba LABS adopted EtherCAT as its new industrial communication standard. Building on an open EtherCAT master implementation and prior community development, iThemba LABS has successfully integrated a variety of EtherCAT hardware into its EPICS control system. This paper presents the open source software toolchain that has been developed and is used at iThemba LABS and showcases several hardware installations at the facility and abroad. Community involvement and future plans for this initiative are also presented., Proceedings of the 22nd International Conference on Cyclotrons and their Applications, Cyclotrons2019, Cape Town, South Africa

With the termination of the neutron and proton therapy programs at iThemba LABS, the use of the Separated Sector Cyclotron (SSC) has now shifted to nuclear physics research with both stable and radioactive ion beams, as well as biomedical research. A dedicated isotope production facility with a commercial 70 MeV H-minus cyclotron has been approved and both the cyclotron and isotope production target stations will be housed in the vaults that were previously used for the therapy programs. The status of this new facility will be reported. In the future the SSC will mostly be used for nuclear physics research, as well as the production of isotopes that cannot be produced with the 70 MeV H-minus cyclotron. At present the production of the alpha-emitting radionuclide Astatine (211At) with a 28 MeV alpha beam is being investigated. Progress with the construction of a facility for production of radioactive beams will be discussed. There will also be reports on development work on the ECR ion sources and progress with implementation of an EPICS control system., Proceedings of the 22nd International Conference on Cyclotrons and their Applications, Cyclotrons2019, Cape Town, South Africa

Ocular melanomas have been treated for the last 20 years at the Helmholtz-Zentrum Berlin in collaboration with the Charité Universitätsmedizin Berlin. However, parts of the initial control system electronics date back to the 1970s, when the machine was installed. Facing a critical shortage of legacy and obsolete components and with the down-time due to failures in the electronics on the increase, a decision was made to install the digital low-level RF control system, developed by iThemba LABS, on our K=132 cyclotron. A short description of the installation and commissioning process, which occurred in April 2017, and the experiences of the first 2 years of operation with the new digital low-level RF control system is presented., Proceedings of the 22nd International Conference on Cyclotrons and their Applications, Cyclotrons2019, Cape Town, South Africa

The SPES* Tape Station (STS) for Radioactive Ion Beams (RIBs) characterization is under construction at LNL. This tool will be used to measure the actual composition of the radioactive ion beams extracted from the SPES-β ion source and to optimize the source’s parameters. STS will provide beam diagnostic information by determining the beam composition and intensity. At the same time, it will be able to measure the target release curves needed for the source’s characterization and development. The core part of the system, the related motor and controls are being designed and constructed in synergy with IPN Orsay (France), iThemba Laboratories (South Africa) and the Gamma collaboration (INFN-CSN3). In particular, the mechanical part is based on the existing BEDO** tape system operated in ALTO while the control system for motion is an EPICS*** base application under implementation by iThemba and INFN, result of a upgrade operation required to substitute obsoleted hardware and update logic and algorithm., Proceedings of the 17th International Conference on Accelerator and Large Experimental Physics Control Systems, ICALEPCS2019, New York, NY, USA

Stable control of amplitude and phase of the radio frequency (RF) system is critical to the operation of cyclotrons. It directly influences system performance, operability, reliability and beam quality. iThemba LABS operates 13 RF systems between 8 and 81 MHz and at power levels of 50 W to 150 kW. A critical drive has been to replace the 30 year old analog RF control system with modern technology. To this effect a new generic digital low-level RF control system has been designed. The system is field programmable gate array (FPGA) based and is capable of synthesizing RF signals between 5 and 100 MHz in steps of 1 µHz. It can achieve a closed-loop amplitude stability of greater than 1/10000 and a closed-loop phase stability of less than 0.01°. Furthermore, the system is fully integrated with the Experimental Physics and Industrial Control System (EPICS) and all system and diagnostic parameters are available to the Control System Studio clients. Three prototypes of the system have been in operation since November 2014. A general analysis of RF control systems as well as the methodology of design, implementation, operational performance and future plans for the system is presented., Proceedings of the 21st Int. Conf. on Cyclotrons and their Applications, Cyclotrons2016, Zurich, Switzerland

This dissertation describes the design and testing of a model of the Synchronization and Video Conversion Unit (SVCU), a subsystem of the tracking radar (TR) at Denel Overberg Test Range (OTR). The SVCU synchronizes all the radar sub-systems and also converts the returned RF target signals to digital numbers. The technology within the SVCU is outdated and spares are scarce if not unattainable. This study forms the first phase of the development of a new SVCU and will determine the specifications of the hardware needed to build the replacement. Models of the transmit and receive chain of the radar were first developed in SystemVueTM. A comprehensive literature review was then done, yielding an accurate model of the current SVCU. The radar model was run, with simulated target and scene parameters, and its output fed into the SVCU model. The output of the SVCU was then processed by a CFAR detector and gated tracking algorithms implemented in MathLang and Python. The simulated target was correctly identified in the range-Doppler plane. The tracking gates (used to measure range and Doppler) were then corrupted with jitter, rise- time and offsets. A statistical analysis was done on the effect of these impurities on the radar measurements. A new SVCU architecture, utilizing high speed ADCs and digital integrators, was then tested. The effects of non-linearities (DNL and INL) in the ADC and phase noise on the ADC sample clock on the radar measurements were analysed. The jitter on the transmit sync (TX), the ADC sample clock and tracking gates were found to be the most critical aspects of the SVCU. To meet the specified measurement accuracy of the radar, the root-sum-square of the jitter on these syncs (jitter budget) must not exceed 30 nanoseconds. A case study was then done to determine the jitter budget achievable in an FPGA-centric SVCU design. The study concluded that a jitter budget of 30 ns is achievable. Moreover, in an FPGA based design the jitter introduced by the interface sending the TX sync from the FPGA (SVCU) to the transmitter assembly will, almost entirely, determine the range accuracy of the TR. From these findings, a new SVCU, based on the RHINO board from the UCT RRSG, was recommended and the future work outlined.