MSc (Med), Community Paediatrics, Faculty of Health Sciences, University of the Witwatersrand / Background: Although breastfeeding is a key child survival strategy, breastfeeding practices in South African health institutions can generally be categorised as being poor. The global Baby-Friendly Hospital Initiative (BFHI), led by UNICEF and the WHO, aims to create a health care environment that promotes breastfeeding as the norm. This study aimed to document practices around breastfeeding support and compliance with the BFHI’s “10 steps to successful breastfeeding” in both baby-friendly accredited and non-accredited facilities. Methods: This was a cross-sectional study, conducted in nine facilities in Gauteng, including tertiary, secondary and districts hospitals, and midwife obstetric units. Convenience sampling was used. Study questionnaires were based on the generic BFHI assessment tool, but were modified to include more detailed investigation of HIV related factors. The questionnaire was verbally administered on-site to 165 mothers of well infants, and 65 nursing staff. Results: Suboptimal practices were identified in both baby-friendly and non-baby-friendly accredited facilities, but more so in the latter. None of the facilities passed all of the 10 BFHI steps. None of the baby-friendly certified institutions achieved a score sufficient to be still deemed baby-friendly. Steps that required advice and support from nursing staff, viz. step 5 (showing mothers how to breastfeed), step 8 (encouraging breastfeeding on demand), and step 10 (breastfeeding support after discharge from the facility), were particularly poorly done in the majority of facilities. Baby-friendly certified institutions were significantly better than non-accredited facilities for steps 2 (training), 4 (initiating breastfeeding within 1 hour), and 7 (rooming-in). Conclusion: Although baby-friendly accredited facilities generally performed better than non-accredited facilities, their performance failed to justify maintenance of their accredited status based on this assessment. However, some positive practices were sustained over time. There is a dire need for greater attention to be directed to the promotion of good breastfeeding practices by health professionals and institutions.

Digitized by Kansas Correctional Industries

Digitized by Kansas Correctional Industries

Digitized by Kansas Correctional Industries

Digitized by Kansas Correctional Industries

Along with the current trend of wireless technology innovation, wideband, compact size, low-profile, lightweight and multiple functional antenna and array designs are becoming more attractive in many applications. Conventional wireless systems utilise omni-directional or sectored antenna systems. The disadvantage of such antenna systems is that the electromagnetic energy, required by a particular user located in a certain direction, is radiated unnecessarily in every direction within the entire cell, hence causing interference to other users in the system. In order to limit this source of interference and direct the energy to the desired user, smart antenna systems have been investigated and developed. This thesis presents the design, simulation, fabrication and full implementation of a novel smart antenna system for future mobile applications. The design and characterisation of a novel antenna structure and four-element liner array geometry for smart antenna systems are proposed in the first stage of this study. Firstly, a miniaturised microstrip-fed planar monopole antenna with Archimedean spiral slots to cover WiFi/Bluetooth and LTE mobile applications has been demonstrated. The fundamental structure of the proposed antenna element is a circular patch, which operates in high frequency range, for the purpose of miniaturising the circuit dimension. In order to achieve a multi-band performance, Archimedean spiral slots, acting as resonance paths, have been etched on the circular patch antenna. Different shapes of Archimedean spiral slots have been investigated and compared. The miniaturised and optimised antenna achieves a bandwidth of 2.2GHz to 2.9GHz covering WiFi/Bluetooth (2.45GHz) and LTE (2.6GHz) mobile standards. Then a four-element linear antenna array geometry utilising the planar monopole elements with Archimedean spiral slots has been described. All the relevant parameters have been studied and evaluated. Different phase shifts are excited for the array elements, and the main beam scanning range has been simulated and analysed. The second stage of the study presents several feeding network structures, which control the amplitude and phase excitations of the smart antenna elements. Research begins with the basic Wilkinson power divider configuration. Then this thesis presents a compact feeding network for circular antenna array, reconfigurable feeding networks for tuning the operating frequency and polarisations, a feeding network on high resistivity silicon (HRS), and an ultrawide-band (UWB) feeding network covering from 0.5GHz to 10GHz. The UWB feeding network is used to establish the smart antenna array system. Different topologies of phase shifters are discussed in the third stage, including ferrite phase shifters and planar phase shifters using switched delay line and loaded transmission line technologies. Diodes, FETs, MMIC and MEMS are integrated into different configurations. Based on the comparison, a low loss and high accurate Hittite MMIC analogue phase shifter has been selected and fully evaluated for this implementation. For the purpose of impedance matching and field matching, compact and ultra wideband CPW-to-Microstrip transitions are utilised between the phase shifters, feeding network and antenna elements. Finally, the fully integrated smart antenna array achieves a 10dB reflection coefficient from 2.25GHz to 2.8GHz, which covers WiFi/Bluetooth (2.45GHz) and LTE (2.6GHz) mobile applications. By appropriately controlling the voltage on the phase shifters, the main beam of the antenna array is steered ±50° and ±52°, for 2.45GHz and 2.6GHz, respectively. Furthermore, the smart antenna array demonstrates a gain of 8.5dBi with 40° 3dB bandwidth in broadside direction, and has more than 10dB side lobe level suppression across the scan. The final stage of the study investigates hardware and software automatic control systems for the smart antenna array. Two microcontrollers PIC18F4550 and LPC1768 are utilised to build the control PCBs. Using the graphical user interfaces provided in this thesis, it is able to configure the beam steering of the smart antenna array, which allows the user to analyse and optimise the signal strength of the received WiFi signals around the mobile device. The design strategies proposed in this thesis contribute to the realisation of adaptable and autonomous smart phone systems.

Digitized by Kansas Correctional Industries

Typescript. / Digitized by Kansas Correctional Industries

The question of which sex of cattle to feed is a basic economic decision which must be made by feeders. An economic analysis of costs and returns associated with feeding steers in comparison to heifers would give feeders some assistance in making this decision. The objectives of this study were to make an economic analysis of feeding a pen of steers and a pen of heifers in a feedlot, then determine the break- even prices for feeder cattle which would make the feeder indifferent to whether he fed steers or heifers , and finally to develop a decision model that could be used by feeders to evaluate this decision for their feedlots. Steers gain faster and more economically than do heifers . Steers, however, must be fed from 40 to 60 days longer in order to reach the quality standards of the choice grade. Steers reach the market at heavier weights both as fat cattle and carcasses. On the other hand heifers sell for less per pound as feeders and finish earlier in the feedlot. A graphical decision model was derived which will a id any given feedlot manager in making the decision of which sex would return more profit. This model allows one to plot the break- even prices and price spreads of feeder steers and heifers . The current market prices of feeder cattle on any given day can be compared to the model , and a decision made as to which sex is most profitable. The break-even spread in feeder cattle prices between steers and heifers gets wider as the price of feeder cattle increases. This explains the wide spread when feeder cattle are selling around 38-40 cents per pound.

No description available.