Cost of implementing a community-based primary health care strengthening program: The case of the Ghana Essential Health Interventions Program in northern Ghana

Background The absence of implementation cost data constrains deliberations on consigning resources to community-based health programs. This paper analyses the cost of implementing strategies for accelerating the expansion of a community-based primary health care program in northern Ghana. Known as the Ghana Essential Health Intervention Program (GEHIP), the project was an embedded implementation science program implemented to provide practical guidance for accelerating the expansion of community-based primary health care and introducing improvements in the range of services community workers can provide. Methods Cost data were systematically collected from intervention and non-intervention districts throughout the implementation period (2012–2014) from a provider perspective. The step-down allocation approach to costing was used while WHO health system blocks were adopted as cost centers. We computed cost without annualizing capital cost to represent financial cost and cost with annualizing capital cost to represent economic cost. Results The per capita financial cost and economic cost of implementing GEHIP over a three-year period was $1.79, and$1.07 respectively. GEHIP comprised only 3.1% of total primary health care cost. Health service delivery comprised the largest component of cost (37.6%), human resources was 28.6%, medicines was 13.6%, leadership/governance was 12.8%, while health information comprised 7.5% of the economic cost of implementing GEHIP. Conclusion The per capita cost of implementing the GEHIP program was low. GEHIP project investments had a catalytic effect that improved community-based health planning and services (CHPS) coverage and enhanced the efficient use of routine health system resources rather than expanding overall primary health care costs

Determination of discrete element model parameters for a cohesive soil and validation through narrow point opener performance analysis

The discrete element method (DEM) is a powerful tool that can be used to predict soil disturbance and soil cutting forces to assist design optimisation of soil cutting tools. In this study, DEM input parameters were calibrated to model a cohesive soil (Black Vertosol of southern Queensland, Australia) using the hysteretic spring contact model, coupled with linear cohesion model, and nominal particle radius of 5 mm. DEM simulations were validated using experimental results for the effects of opener rake angle and cutting edge chamfer, and bentleg opener shank offset on no-tillage narrow point opener performance. Overall, DEM results closely agreed with experimental results and exhibited similar trends. By using particle displacement analysis to predict loosened furrow boundary, most predictions of furrow parameters namely furrow cross-sectional area, furrow width, and critical depth had relative errors ranging from 1 % to 19 %. Lateral soil throw was predicted with relative errors of 0.2 %–9 %, except for the straight opener with 45° rake angle (-32 %). Ridge height was over predicted in all cases due to larger DEM particles than actual soil particles used. Relative errors of 20 %, 22 %, -31 %, and -5 % in draught were recorded for the straight openers with 90° (blunt), 90° (chamfered), and 45° rake angles, and the bentleg opener, respectively. These results show that DEM and the input parameters determined to model the cohesive soil of this study can be used to reliably assess furrow opener performance

Evaluation of bentleg and straight narrow point openers in cohesive soil

The bentleg opener was developed to overcome the high soil disturbance caused by straight narrow point openers, with the original evaluation conducted on sandy soils. A bentleg furrow opener was compared to narrow point openers with varying rake angles (45° and 90°) and cutting edge cross-sections (blunt, and single- and double-side chamfers) for soil disturbance, tillage forces, and soil aggregate break down in Black Vertosol (Vertisol in the USDA Soil Taxonomy), a highly cohesive soil relative to sandy soils used previously. Whereas the 45° rake angle caused greater soil disturbance, produced larger soil aggregates, and reduced draught and vertical force requirements, all openers with 90° rake angle (blunt and chamfered openers) had a shallow critical depth (44–46 mm) and caused smearing. Contrary to previous findings in sandy soil, both single and double side chamfering of opener cutting edge had no significant effect on soil movement, furrow width, and furrow cross-sectional area. However, greater soil movement was observed on the chamfered side of the single-side chamfered opener than the non-chamfered side. The chamfers significantly reduced draught and vertical forces and produced smaller soil aggregates. The bentleg opener loosened soil to the furrow bottom but caused the least soil movement out of the furrow and formed a ridge in the middle of the furrow, which resulted in the highest furrow backfill. It also encountered a downward vertical force which assisted penetration and had a greater proportion of aggregates within the optimum range (1.18 and 9.5 mm). The bentleg opener, thus, shows potential for improved seed covering and satisfactory performance at operating speeds above 8 km h−1

No-tillage furrow opener performance: a review of tool geometry, settings and interactions with soil and crop residue

The primary features of an effective and efficient furrow opener include controlled soil disturbance and low draught and vertical force requirements. When integrated in a no-tillage seeding system, furrow openers should also have the ability to assist, and not hinder, the functions of seeding system components – such as maintaining adequate surface residue distribution, accurate and uniform placement of seeds and fertiliser, and regular inter-plant spacing. This review highlights how these goals are affected by opener type, geometry and settings, and soil and residue conditions. Typically, tine openers cause greater soil disturbance than disc openers whereas disc openers are likely to cause residue hairpinning. Winged tine openers reduce residue interference with seed placement and support greater lateral seed spread. Inverted-T openers can achieve subsurface soil shattering, which helps conserve moisture and provides good seed–soil contact. A tine opener with concave cutting edge reduces soil disturbance relative to straight and convex cutting edges. Increasing rake angle, tine width and operating depth increase degree of soil disturbance and draught requirement. Increasing forward speed reduces residue interference with sowing but might decrease the accuracy and uniformity of depth and separation of seed and fertiliser placement. Relative to common openers, bentleg openers have lower draught and penetration force requirements while combining minimal lateral soil throw with high furrow backfill, even at speeds of up to 16 km h–1. The performance of bentleg openers need to be evaluated under residue conditions and in cohesive and adhesive soils. Recommendations for future research are presented

Analysis of effects of operating speed and depth on bentleg opener performance in cohesive soil using the discrete element method

High operating speeds are desirable, different seeding depths are required, and low soil disturbance is necessary for sowing in no-tillage farming. The effects of operating speed (8–16 km h−1) and depth (60–120 mm) on bentleg opener (four variations) performance were analysed in comparison to straight openers in a virtual soil bin using the discrete element method (DEM). Generally, increasing operating depth and speed resulted in increased soil disturbance and reaction forces. However, the bentleg openers loosened furrows down to the furrow bottom and caused less lateral soil throw at all operating depths and speeds. Bentleg openers, particularly without foot, increased furrow width by lower magnitudes compared with straight openers as operating speed was increased. The greatest lateral soil throw beyond furrow banks recorded for the bentleg openers at operating speed and depth of 16 km h−1 and 60 mm were less than the least for the straight openers, except for the footless bentleg with forward raked side leg. Backward raked side leg had the lowest impact on lateral soil throw and spill over distance with increasing operating speed. Increasing operating speed shifted the main ridge created by the bentleg openers above the furrow’s centre outward to the left. Furrow backfill of 97–100% was achieved with the bentleg openers. Bentleg openers with 45° foot rake angle required the lowest draught and vertical forces. Backward raked side leg resulted in the highest draught force among the bentleg openers and the greatest vertical (penetration) force among all the opener

Analysis of effect of bentleg opener geometry on performance in cohesive soil using the discrete element method

Bentleg furrow openers can significantly reduce soil disturbance and reaction forces relative to conventional narrow point openers used in no-tillage farming. The effect of bentleg opener geometry on soil disturbance and reaction forces in a cohesive soil was assessed in a virtual soil bin using the discrete element method. Soil disturbance and reaction forces at an operating depth and a speed of 100 mm and 8 km h−1, were shown to be minimised by using (1) a shank lateral offset of 70 mm, (2) a side leg bend angle that ensures the elbow, which is the transition between the side leg and vertical shank, is not located below the soil surface, (3) an arched instead of angled elbow, (4) a cutting edge chamfer angle as low as practical, and (5) tine thickness as small as practical. Furrow size was found to be more dependent on shank lateral offset and side leg bend angle than side leg forward angle. Though side leg forward angles >90° reduce particle displacement and will work better in fields with stones and roots, they also considerably increase draught and penetration resistance. A low rake angled foot minimises soil reaction forces and drives soil loosening. Reducing foot height and interaction of the vertical shank with soil particles minimises surface soil displacement. These results have expanded the understanding of bentleg opener mechanics and are in close agreement with those reported for sandy soils. Therefore, similar criteria can be followed to optimise bentleg opener design for different soil types