Human resources for health care delivery in Tanzania: a multifaceted problem

BACKGROUND: Recent years have seen an unprecedented increase in funds for procurement of health commodities in developing countries. A major challenge now is the efficient delivery of commodities and services to improve population health. With this in mind, we documented staffing levels and productivity in peripheral health facilities in southern Tanzania. METHOD: A health facility survey was conducted to collect data on staff employed, their main tasks, availability on the day of the survey, reasons for absenteeism, and experience of supervisory visits from District Health Teams. In-depth interview with health workers was done to explore their perception of work load. A time and motion study of nurses in the Reproductive and Child Health (RCH) clinics documented their time use by task. RESULTS: We found that only 14% (122/854) of the recommended number of nurses and 20% (90/441) of the clinical staff had been employed at the facilities. Furthermore, 44% of clinical staff was not available on the day of the survey. Various reasons were given for this. Amongst the clinical staff, 38% were absent because of attendance to seminar sessions, 8% because of long-training, 25% were on official travel and 20% were on leave. RCH clinic nurses were present for 7 hours a day, but only worked productively for 57% of time present at facility. Almost two-third of facilities had received less than 3 visits from district health teams during the 6 months preceding the survey. CONCLUSION: This study documented inadequate staffing of health facilities, a high degree of absenteeism, low productivity of the staff who were present and inadequate supervision in peripheral Tanzanian health facilities. The implications of these findings are discussed in the context of decentralized health care in Tanzania

Track E Implementation Science, Health Systems and Economics

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138412/1/jia218443.pd

Micromechanisms of short fatigue crack growth in an Al-Si piston alloy

The short fatigue crack growth behaviour of a model cast aluminium piston alloy has been investigated. This has been achieved using a combination of fatigue crack replication methods at various intervals during fatigue testing and post-mortem analysis of the crack profiles. Crack-microstructure interactions have been clearly delineated using a combination of optical microscopy and scanning electron microscopy. Results show that intermetallic particles and eutectic Al-Si regions play a significant role in determining the crack path and growth rate of short fatigue cracks. It is observed that the growth of short cracks is often retarded or even arrested at intermetallic particles and Al-Si eutectic regions. Crack deflection at intermetallics and eutectic Si is also frequently observed. These results have been compared with the long crack growth behaviour of the alloy

Analysis of microstructure and fatigue micromechanisms in cast aluminium piston alloys

Light vehicle engine pistons have traditionally been cast from near eutectic Al-Si cast alloys due to several favourable functional and processing attributes. The increasingly demanding engine performance requirements have necessitated the need for the development of multicomponent alloys with high alloy content and highly complex microstructure. In this regard, recent trends in new piston alloy development have been to increase the level of various alloying elements such as Cu, Ni and even Si. However, low Si compositions of ?7 wt% Si and ?0.7 wt% Si have also been proposed largely due to observations that the large blocky primary Si particles found in the near-eutectic alloys are potent fatigue crack initiators. Nonetheless, previous research on these low Si piston alloys has demonstrated that their fatigue performance is significantly impaired by porosity which increases with decreasing Si content. With improved processing techniques, porosity can be reduced to levels that make it impotent in fatigue failure processes. The aim of this work was therefore to characterise the microstructure and fatigue micromechanisms of the low Si piston alloys after hot isostatic pressing (hipping) to reduce porosity. This was achieved using a combination of various imaging tools and fatigue testing to establish the role of microstructure on initiation and growth of fatigue cracks. It has been demonstrated using X-ray microtomography that hipping significantly reduces porosity, especially in the 0.7 wt% Si alloy, while the intermetallic structures remain largely unaffected. The eutectic Si particles in the 7 wt% Si alloy are however transformed from a fine fibrous interconnected structure to coarse, spheroidised and discrete particles. Hipping has also been observed to improve the fatigue performance of the 0.7 wt% Si alloy due to the significant reduction in porosity. Fatigue crack initiation has been observed to occur mainly at intermetallic particles in both alloys after hipping and, consistent with previous work, the most frequent crack initiating phase is found to be Al 9 FeNi. Analysis of short fatigue crack growth profiles has shown that intermetallics and eutectic Si particles preferentially debond, thus providing a weak path for crack propagation along their interfaces with the ?-Al matrix. However, grain boundaries as well as these hard particles have also been shown to frequently act as effective barriers to crack growth. On the other hand, long fatigue crack growth analysis has shown that fatigue cracks tend to avoid Si and/or intermetallic particles at low ?K levels (up to ?K?7 MPa?m). At higher levels of ?K, the cracks increasingly seek out these hard particles up to a ?K of ?9 MPa?m after which the crack preferentially propagates through them. It has also been observed that crack interaction with intermetallics causes significant crack deflection which may result in roughness related closure mechanisms to be activated

A case study on unsafe abortion and post abortion complications in a 23-year-old lady in Kenya

No Abstract.&nbsp

Micromechanisms of fatigue crack growth in cast aluminium piston alloys

The fatigue crack growth behaviour in as-cast and hot isostatically pressed (HIP) model cast aluminiumpiston alloys with hypoeutectic Si compositions of 6.9 wt% and 0.67 wt% has been investigated. The HIPalloys showed slightly improved fatigue crack growth resistance. Analysis of the crack path profiles andfracture surfaces showed that the crack tends to avoid Si and intermetallic particles at low DK levels up toa mid-DK of approx. 7 MPa root m. However, some particles do fail ahead of the crack tip to facilitate crack advancedue to the interconnected microstructure of these alloys. At higher levels of DK, the crack increasinglyseeks out Si and intermetallic particles up to a DK of approx. 9 MPa root m after which the crack preferentiallypropagates through intermetallic particles in the 0.67 wt%Si alloy or Si and intermetallics in the 6.9 wt%Sialloys. It was also observed that crack interaction with intermetallics caused crack deflections that led toroughness-induced crack closure and possibly oxide-induced crack closure at low to mid-DK. However,crack closure appears unimportant at high DK due to the large crack openings and evidenced by the fastcrack growth rates observed

Application of X-Ray microtomography to evaluate complex microstructure and predict the lower bound fatigue potential of cast Al–7(0.7)Si–4Cu–3Ni–Mg alloys

The 3D architecture of intermetallics and porosity in two multicomponent cast Al–7(0.7)Si–4Cu–3Ni–Mg alloys is characterized using conventional microscopy and X-ray microtomography. The two alloys are found to contain intermetallic phases such as Al3Ni, Al3(NiCu)2, Al9FeNi, and Al5Cu2Mg8Si6 that have complex networked morphology in 3D. The results also show that HIPping does not significantly affect the volume fraction, size, and shape distribution of the intermetallic phases in both alloys. A novel technique similar to serial sectioning that circumvents quantification difficulties associated with interconnected particles is used to quantify the intermetallics. The largest particle size distribution is then correlated to fatigue performance using extreme value analysis to predict the maximum particle size in a sample of S-N fatigue specimens and subsequently, the lower bound fatigue life. The predictions are found to correlate well with fatigue data. The effect of HIPping on porosity characteristics is also characterized. Large pore clusters with complex morphology are observed in the unHIPped versions of both alloys, but more significant in the low Si (Al–0.7Si–4Cu–3Ni–Mg) alloy. However, these are significantly reduced after HIPping. The differences between 2D and 3D pore morphology and size distribution is discussed in terms of the appropriate pore size parameter for fatigue life prediction

Analysis of fatigue crack initiation and S-N response of model cast aluminium piston alloys

Fatigue crack initiation and S-N fatigue behaviour of hipped model Al7Si-Sr and Al0.7Si piston alloys have been investigated after overaging at 260oC for 100 h to provide a practical simulation of in-service conditions. The results show that hipping did not affect the S-N behaviour of Al7Si- Sr. This is attributed to the lack of significant change in porosity distribution in this alloy because of its low porosity levels even in the unhipped state. However, hipping profoundly improved the fatigue performance of alloy Al0.7Si due to the significant reduction in porosity. In this investigation, it was observed that porosity was rendered impotent as a fatigue crack initiator in both hipped alloys. Instead, fatigue cracks were observed to originate mainly from intermetallic particles (particularly the Al9FeNi phase) in both alloys and sometimes from oxide particles in Al0.7Si alloy. Fatigue cracking was also frequently observed at intermetallic clusters in hipped Al0.7Si. The observed scatter in fatigue life is discussed in terms of the size of fatigue crack initiating particles and the overall particle size distribution which follows a power law distribution functio