The Effect of Rock Phosphate on Soil Nutrient Dynamics, Growth, Development and Yield of Oil Palm in The Semi-Deciduous Forest Zone of Ghana

Field experiment was conducted at Oil Palm Research Institute, Kusi from 2002 to 2007 to as-sess the effect of Phosphate Rock (PR) on soil nutrient dynamics, growth, development and yield of oil palm. The study was carried out on the soils of Nzema series classified as Ferric Acrisols and Typic Hapludult. The oil palm trees selected were 8 year old tenera (DXP ex OPRI). Each plot measured 17.6 m x 17.6 m and had 6 palm trees. There were four treatments arranged in randomized complete block design with four replicates. The treatments included: 1). TSP - OPRI fertilizer recommendation - 222 kg of AS + 222 kg of TSP + 296 kg of MOP/ha/yr (control); 2). PR1 - PR 715 kg + 222 kg of AS + 296 kg of MOP/ha - Yr 1. PR 358 kg + 222 kg of AS + 296 kg of MOP/ ha – Yr 2. PR 358 kg + 222 kg of AS + 296 kg of MOP/ha – Yr 3; 3). PR2 - PR 1428 kg + 222 kg of AS + 296 kg of MOP/ha applied once in every 5 years; 4). PR3 - PR 142.85 kg/ha +222 kg AS/ ha + 296 kg of MOP/ha applied twice in every 5 years. Application of treatments influenced the soil chemical properties to a varying extent. Gradual increase in soil nutrient lev-els were more pronounced in RP treatments than Triple Super Phosphate (TSP) treatment (control). Soil pH increased from extremely acidic (3.73) to acidic (5.43) for treatment PR2. At the end of the study, available P recorded 9.55 mg/kg. The value is slightly below the medium range of available P for oil palm production. Significant increases were recorded by RP treat-ments for exchangeable Ca, Mg, K and ECEC. The results showed that treatment PR2 was effec-tive and gave the highest oil palm yield of 62.8t/ha with TSP recording 53.7t/ha. For sustained levels of soil nutrients, growth, development and yield of oil palm, PR incorporation should be encouraged.Keywords: Phosphate Rock, nutrient dynamics, oil palm, triple super phosphat

Comparison of clinical outcomes between active and permissive blood pressure management in extremely preterm infants.

BACKGROUND: There remains uncertainty about the definition of normal blood pressure (BP), and when to initiate treatment for hypotension for extremely preterm infants. To determine the short-term outcomes of extremely preterm infants managed by active compared with permissive BP support regimens during the first 72 hours of life. METHOD: This is a retrospective medical records review of 23 +0-28 +6 weeks' gestational age (GA) infants admitted to neonatal units (NNU) with active BP support (aimed to maintain mean arterial BP (MABP) >30 mmHg irrespective of the GA) and permissive BP support (used medication only when babies developed signs of hypotension) regimens. Babies admitted after 12 hours of age, or whose BP data were not available were excluded. RESULTS: There were 764 infants admitted to the participating hospitals; 671 (88%) were included in the analysis (263 active BP support and 408 permissive BP support). The mean gestational age, birth weight, admission temperature, clinical risk index for babies (CRIB) score and first haemoglobin of infants were comparable between the groups. Active BP support group infants had consistently higher MABP and systolic BP throughout the first 72 hours of life (pgrade 2 intra ventricular haemorrhage (IVH). Death before discharge (adjusted OR 1.38 (0.88 - 2.16)) or IVH (1.38 (0.96 - 1.98)) was similar between the two groups. Necrotising enterocolitis (NEC) ≥stage 2 was significantly higher in permissive BP support group infants (1.65 (1.07 - 2.50)). CONCLUSIONS: There was no difference in mortality or IVH between the two BP management approaches. Active BP support may reduce NEC. This should be investigated prospectively in large multicentre randomised studies

The Prevalence and Risk Factors of Hepatitis B Virus Infection Among Dwellers in A Peri-Urban District of Ghana: A Cross-Sectional Study

Hepatitis B virus (HBV) infection is a significant health issue affecting about 296 million people worldwide. The disease is of great public health concern in Ghana as the country is within the endemic region of HBV infection. This study sought to determine the prevalence of HBV infection and associated risk factors among dwellers in a peri-urban district of Ghana. This cross-sectional descriptive study was conducted in the Sunyani West District of the Bono Region of Ghana. Respondents aged ≥18 years were purposively recruited from the four major towns in the District with health centres. A questionnaire was used to collect data from participants, and a rapid diagnostic test for the sero-presence or otherwise of hepatitis B infection was conducted. A total of 992 respondents took part in the study, with the prevalence of HBV infection using HBsAg as a marker among all the study participants being 2.9% (male 4.0% (12/298), female 2.5% (17/694)). Females aged between 20-29 years had a comparatively higher prevalence of hepatitis B infection than their corresponding males. The intake of alcohol (RR=4.23; 95% CI:2.05-8.74, p <0.000), previously diagnosed of having a sexually transmitted disease (RR= 2.43; 95% CI: 1.03-5.71, p = .04) and having multiple sexual partners (RR= 2.27; 95% CI: 1.11-4.65, p = .02) were the significant risk factors for HBV infection among the study participants. The study showed a low prevalence of HBV infection in the Sunyani West District of Ghana using HBsAg as a serum marker to diagnose the infection. Keywords: Hepatitis, prevalence, risk factors, Sunyani Wes

Non-Native R1 Substitution in the S4 Domain Uniquely Alters Kv4.3 Channel Gating

The S4 transmembrane domain in Shaker (Kv1) voltage-sensitive potassium channels has four basic residues (R1–R4) that are responsible for carrying the majority of gating charge. In Kv4 channels, however, R1 is replaced by a neutral valine at position 287. Among other differences, Kv4 channels display prominent closed state inactivation, a mechanism which is minimal in Shaker. To determine if the absence of R1 is responsible for important variation in gating characteristics between the two channel types, we introduced the V287R mutant into Kv4.3 and analyzed its effects on several voltage sensitive gating transitions. We found that the mutant increased the voltage sensitivity of steady-state activation and altered the kinetics of activation and deactivation processes. Although the kinetics of macroscopic inactivation were minimally affected, the characteristics of closed-state inactivation and recovery from open and closed inactivated states were significantly altered. The absence of R1 can only partially account for differences in the effective voltage sensitivity of gating between Shaker and Kv4.3. These results suggest that the S4 domain serves an important functional role in Kv4 channel activation and deactivation processes, and also those of closed-state inactivation and recovery

Malaria Attributable to the HIV-1 Epidemic, Sub-Saharan Africa

The HIV-1 epidemic has increased the malaria disease and death rate in southern Africa

Distribution of causes of maternal mortality among different socio-demographic groups in Ghana; a descriptive study

BACKGROUND: Ghana's maternal mortality ratio remains high despite efforts made to meet Millennium Development Goal 5. A number of studies have been conducted on maternal mortality in Ghana; however, little is known about how the causes of maternal mortality are distributed in different socio-demographic subgroups. Therefore the aim of this study was to assess and analyse the causes of maternal mortality according to socio-demographic factors in Ghana.METHODS: The causes of maternal deaths were assessed with respect to age, educational level, rural/urban residence status and marital status. Data from a five year retrospective survey was used. The data was obtained from Ghana Maternal Health Survey 2007 acquired from the database of Ghana Statistical Service. A total of 605 maternal deaths within the age group 12-49 years were analysed using frequency tables, cross-tabulations and logistic regression.RESULTS: Haemorrhage was the highest cause of maternal mortality (22.8%). Married women had a significantly higher risk of dying from haemorrhage, compared with single women (adjusted OR = 2.7, 95%CI = 1.2-5.7). On the contrary, married women showed a significantly reduced risk of dying from abortion compared to single women (adjusted OR = 0.2, 95%CI = 0.1-0.4). Women aged 35-39 years had a significantly higher risk of dying from haemorrhage (aOR 2.6, 95%CI = 1.4-4.9), whereas they were at a lower risk of dying from abortion (aOR 0.3, 95% CI = 0.1-0.7) compared to their younger counterparts. The risk of maternal death from infectious diseases decreased with increasing maternal age, whereas the risk of dying from miscellaneous causes increased with increasing age.CONCLUSIONS: The study shows evidence of variations in the causes of maternal mortality among different socio-demographic subgroups in Ghana that should not be overlooked. It is therefore recommended that interventions aimed at combating the high maternal mortality in Ghana should be both cause-specific as well as target-specific

Experimental study on flexural behaviours of fresh or aged hollow reinforced concrete girders strengthened by prestressed CFRP plates

The paper presents a well-rounded experimental study on the flexural performance of Reinforced Concrete (RC) box girders strengthened with prestressed carbon fibre reinforced polymer (CFRP) plates. The motivation behind the study was twofold: the rising need for structural reinforcement of existing aged and heavily utilised hollow RC box girders, and the absence of prior attempts to integrate prestressed CFRP plate strengthening for those hollow girders. Previous experimental studies are scarce and fewer studies are focused on the combined prestress and thin-wall effects, such as prestress-related stress condensation and shear lag. However, experimental results are important in directing further analytical studies for hollow sections with more complex behaviours than solid sections since there is a need to predict the behaviour of the prestress-strengthened hollow RC structures for routine design. This pivotal experimental study aims to quantify the structural interactions initiated by prestress in hollow sections and evaluate the impact of age while promoting further analytical initiatives. In this study, two types of CFRP plates, ordinary CFRP and steel-wire-CFRP (SW-CFRP), were used on different specimen beams with varying prestressing levels, sizes of the CFRP plates, and pre-damaged states representing aged and over-used members. Their performance indexes, including cracking load, yield load, ultimate load, structural stiffness, ductility, and crack resistance, were tested and summarised in this paper. The CFRP plates of the eight specimen beams were prestressed to different levels (non-prestressed, and 30% and 40% of the CFRP plate's ultimate strength). The test results suggest that the crack load increased by 86% and 134%, when the specimens were enhanced with the combinations of 30% prestress level for the same CFRP cross-section, and 40% prestress level with a thicker CFRP plate, respectively. The flexural capacity also increased by 42% and 72%, and flexural stiffness increased by 3% and 63%, respectively. The experimental results proved that the proposed prestressed CFRP plate technology effectively strengthens the new or aged RC box girders, but the ductility is sacrificed. These first-hand test results provide an excellent target dataset for further development in the analysis and design of prestressed CFRP plate-strengthened RC box girders

The Angiotensin Converting Enzyme Insertion/Deletion polymorphism is not associated with an increased risk of death or bronchopulmonary dysplasia in ventilated very low birth weight infants

BACKGROUND: The ACE gene contains a polymorphism consisting of either the presence (insertion, I) or absence (deletion, D) of a 287 bp alu repeat in intron 16. The D allele is associated with increased ACE activity in both tissue and plasma. The DD genotype is associated with risk of developing ARDS and mortality. The frequency of the D allele is higher in patients with pulmonary fibrosis, sarcoidosis and berylliosis. The role of this polymorphism has not been studied in the development of BPD in the premature newborn. METHODS: ACE I/D genotype was determined in 245 (194 African-American, 47 Caucasian and 4 Hispanic) mechanically ventilated infants weighing less than 1250 grams at birth and compared to outcome (death and/or development of BPD). RESULTS: The incidence of the D allele in the study population was 0.58. Eighty-eight (35.9%) infants were homozygous DD, 107 (43.7%) were heterozygous ID and 50 (20.4%) were homozygous II. There were no significant differences between genotype groups with respect to ethnic origin, birth weight, gestation, or gender. There was no effect of the ACE I/D polymorphism on mortality or development of BPD (O(2 )on 28 days or 36 weeks PCA). Secondary outcomes (intraventricular hemorrhage and periventricular leukomalacia) similarly were not influenced by the ACE ID polymorphism. CONCLUSIONS: The ACE I/D polymorphism does not significantly influence the development of BPD in ventilated infants less than 1250 grams

Looking back and moving forward: 50 years of soil and soil fertility management research in sub-Saharan Africa

Article purchased; Published online: 02 Nov 2017Low and declining soil fertility has been recognized for a long time as a major impediment to intensifying agriculture in sub-Saharan Africa (SSA). Consequently, from the inception of international agricultural research, centres operating in SSA have had a research programme focusing on soil and soil fertility management, including the International Institute of Tropical Agriculture (IITA). The scope, content, and approaches of soil and soil fertility management research have changed over the past decades in response to lessons learnt and internal and external drivers and this paper uses IITA as a case study to document and analyse the consequences of strategic decisions taken on technology development, validation, and ultimately uptake by smallholder farmers in SSA. After an initial section describing the external environment within which soil and soil fertility management research is operating, various dimensions of this research area are covered: (i) ‘strategic research’, ‘Research for Development’, partnerships, and balancing acts, (ii) changing role of characterization due to the expansion in geographical scope and shift from soils to farms and livelihoods, (iii) technology development: changes in vision, content, and scale of intervention, (iv) technology validation and delivery to farming communities, and (v) impact and feedback to the technology development and validation process. Each of the above sections follows a chronological approach, covering the last five decades (from the late 1960s till today). The paper ends with a number of lessons learnt which could be considered for future initiatives aiming at developing and delivering improved soil and soil fertility management practices to smallholder farming communities in SSA