Linking Optical SPOT and Unmanned Aerial Vehicle data for a rapid biomass estimation in a Forest-savanna Transitional Zone of Ghana

The direct estimation of biomass using remote sensing technologies, such as LiDAR, RaDAR and Stereo Data is limited in utility, since it does not allow for historical analysis of biomass dynamics far back in time due to their recency in development. This study links Unmanned Aerial Vehicle (UAV)-measured tree height and optical SPOT image reflectance in a mathematical model for a quick and less expensive indirect biomass estimation, and the possibility of historical analysis using the earliest captured optical data. SPOT 6/7 images were used to map land-use/cover patterns. A Phantom 4 drone images were used for height and crown width estimation. A stepwise regression analysis was conducted to establish a relationship between SPOT 6/7 channels and the UAV-generated tree heights. The linear model was used to convert the reflectance values of SPOT images into tree heights, and in turn used for crown width estimation. The estimated tree height and crown width images were used to estimate biomass using an allometric equation. There was no statistically significant difference between UAV and manual tree height measurements. UAV-estimated tree height predicted 88.0% of crown width. Regressing the tree height on the SPOT bands yielded an R2 of 66.0%. It is recommended that further studies be conducted to improve on the accuracy of estimation. It is hoped this would facilitate a quick biomass estimation and long term historical dynamics

Mycorrhizal Association and its Benefits to Allanblackia parviflora Tree Seedlings in the Nursery

Allanblackia species are high value multipurpose indigenous fruit trees whose seeds contain edible oil that has become a foreign exchange earner for rural-based enterprises. Wild harvesting could not sustain the supply to industry and therefore domestication was focused on developing propagation techniques, selecting and collecting elite planting materials. Little emphasis was placed on the soil nutrient requirements where preliminary results showed seedlings grown in rhizosphere soil of wild trees had good growth performance. A study was undertaken to examine microbial-Allanblackia parviflora plant interactions and determine their benefits to nursery seedlings. Roots of wildlings and rhizosphere soil from A. parviflora trees were collected from three forest reserves and the roots assessed for mycorrhizal colonization. Allanblackia parviflora seedlings were raised in different potting media with different ratios and their height and diameter determined. Soil treatments were also analyzed for nutrient and chemical contents. Vesicles, arbuscular structures, hyphal coils and intercellular hyphae were found on root tips of wildlings collected from rhizosphere soil of Allanblackia (AB) trees and seedlings grown in soil treatments containing AB soil. Root colonization of A. parviflora was largely in the form of extensive cell-to-cell growth of hyphal coils characteristic of Paris-type morphology. Addition of Agricultural field soil (Ferric Acrisol, Afs) or Humus (H)+Afs to AB improved height of seedlings. Seedlings grown in AB soil alone increased best in height with age followed by those grown in combination of 75% AB soil and 25% Afs. Available P was highest in Afs (220.84 mgP/kg) and low in AB soil (6.54 mgP/kg) while combination of H + Afs to AB increased K level to 341.34 mgK/kg. The improvement in growth must be due to both vesicular-arbuscular mycorrhizal fungi and soil chemical content of AB soil

Suspended sediment transport into a water supply reservoir in southern Ghana

Weija reservoir on the Densu river serves as a source of water supply to parts of Greater Accra and Central regions of Ghana. The Densu river basin is characterised by accelerated land degradation. A number of Integrated Water Resources Management (IWRM) interventions have been implemented in the basin. Reports suggest there has been an improvement of physicochemical parameters of the water resources. However, there is no recent study on fluvial sediment transport in the basin. This paper assessed sediment transport into the Weija reservoir via the Densu River. Weekly suspended sediment concentration and river discharge were monitored over a 1 year period to quantify sediment yield into the reservoir. The results indicated that total annual suspended sediment yield, and annual specific suspended sediment yield were 5375 t yr-1 and 2.0 t km-2 yr-1, respectively. These were relatively low compared to results obtained by past studies on the Densu basin at upstream Mangoase (6146 t yr-1 and 2.49 t km-2 yr-1) and other river basins in Ghana. Parameters established from a yield rating curve indicated that parts of the basin were degraded and sediment transport in the basin was largely due to the availability of sediment in the catchment and not just due to high river discharges. The relatively low sediment transport at Weija may be indicative of the success of the IWRM interventions. It is recommended that these be sustained and/or intensified

In vivo anti-malarial potentials of some plants extracts on ICR-mice, Mus musculus

Five medicinal plants, Acacia nilotica (Fabaceae), Citrus aurantifolia (Rutaceae), Mangifera indica (Anacardiaceae) Carica papaya (Caricaceae), and Psidium guajava (Myrtaceae) used for the treatment of malaria/ fever by the Hausa people of Kano-Nigeria were selected based on their traditional claims. These were extracted using ethanol. The in vitro antiplasmodial activities of these extracts against laboratory adapted chloroquine susceptible strain of Plasmodium falciparum (3D7) were earlier reported (Dabo et al. 2013). This study was conducted to evaluate the in vivo antiplasmodial activity of four of these extracts using icr mice in the 4-day suppressive test against P. berghei. The extracts evaluated were: Acacia nilotica (Fabaceae) stem extract coded as ANSF1; Citrus aurantifolia (Rutaceae) leaf extract coded as CALF1; Mangifera indica (Anacardiaceae) leaf extract coded as MILF1 and combination of C. aurantifolia, Carica papaya (Caricaceae), M. indica and Psidium guajava (Myrtaceae) leaves extract coded as CBLF1. CALF1, ANSF1 and CBLF1 (combination) exhibited appreciable degree of suppression of 31.06%, 25.16 and %16.35% respectively. MILF1 did not exhibit any suppression against the P. berghei parasite in vivo at all. With the exception of haemoglobin content (P<0.0363), haematological analysis of the various blood parameters of mice in the control and treated mice indicated no statistical difference (P>0.05). Thus it can be concluded that, the apparent absence of changes in haematological profile alongside activities exhibited by CALF1 (Rutaceae), CBLF1 (a combination) and ANSF1 (Fabaceae),) suggest the bio-availability and antiplasmodial activities of the active substances in the plants evaluated.Keywords: Antimalaria; In vivo, Plants Extracts; Mus musculus; Plasmodium berghei

Use of the Triple-Layer Hermetic Bag against the Maize Weevil, Sitophilus Zeamais (Mots) in Three Varieties of Maize

Maize ranks with wheat and rice as one of the world’s chief grain crops. However, the safety of this important food crop is threatened by pests such as insects, rodents and moulds which results from inappropriate storage methods. Insect pest infestation accounts for about 20-50% of all food crop losses. This study was carried under ambient laboratory conditions of 32± 2oC and 72-88% r.h to determine the effectiveness of the triple-layer hermetic bag in controlling the maize weevil Sitophilus zeamais (Mot) on three varieties of maize (Obatampa, Abrodenkye and Kamangkpong). Five (5) kilograms of each variety with three replicates were infested with 50 S. zeamais and stored for three (3) months in three different types of bags (hermetic, Polypropylene and Jute). Destructive sampling was done monthly to determine the moisture content, viability of each variety and weight loss after storage. Percentage damage of grain due to S. zeamais was assessed on the different types of storage bags. The results show that the high yielding Obatampa was more susceptible to S. zeamais than the two local varieties; Abrodenkye and Kamangkpong. Damage, weight loss and germination rates were significantly (p  higher in the polypropylene and jute bags than the hermetic bags. These were also dependent on the length of storage. The triple-layer hermetic bags were effective against S. zeamais and could be used for storage of maize. Keywords: Maize weevil, Sitophilus zeamais; Triple-layer hermetic bag; Polypropylene; Jute

Multiyear Rainfall and Temperature Trends in the Volta River Basin and their Potential Impact on Hydropower Generation in Ghana

The effects of temperature and rainfall changes on hydropower generation in Ghana from 1960–2011 were examined to understand country-wide trends of climate variability. Moreover, the discharge and the water level trends for the Akosombo reservoir from 1965–2014 were examined using the Mann-Kendall test statistic to assess localised changes. The annual temperature trend was positive while rainfall showed both negative and positive trends in different parts of the country. However, these trends were not statistically significant in the study regions in 1960 to 2011. Rainfall was not evenly distributed throughout the years, with the highest rainfall recorded between 1960 and 1970 and the lowest rainfalls between 2000 and 2011. The Mann-Kendall test shows an upward trend for the discharge of the Akosombo reservoir and a downward trend for the water level. However, the discharge irregularities of the reservoir do not necessarily affect the energy generated from the Akosombo plant, but rather the regular low flow of water into the reservoir affected power generation. This is the major concern for the operations of the Akosombo hydropower plant for energy generation in Ghana

Assessment of Heavy Metal Contamination and Distribution in Surface Soils and Plants along the West Coast of Ghana

Onshore oil drilling activity is ongoing at Jubilee oil fields, Ghana. This activity could lead to heavy metal exposure with consequential adverse effects on public health in nearby coastal communities. Therefore, we assessed heavy metal levels and spatial distribution in soils and plants from the west coast of Ghana to obtain baseline values for monitoring heavy metal exposure. Surface soils were collected from six coastal communities, and analyzed for arsenic, cadmium, copper, mercury, lead, selenium and zinc using atomic absorption spectrophotometer. Mean heavy metal concentrations in soil samples were 2.06, 6.55, 0.016, 21.59, 0.18 and 39.49mg/kg for arsenic, copper, mercury, lead, selenium and zinc, respectively. Mean heavy metal concentrations in plants were 2.70, 17.47, 3.17, 91.74, 1.51 and 9.88mg/kg for arsenic, cadmium, copper, lead, selenium and zinc, respectively. Concentrations of arsenic, cadmium and lead in plants exceeded WHO/FAO permissible limits. Enrichment factor for arsenic was significant and extremely high for selenium, while geoaccumulation index showed moderate pollution for selenium. Soil contamination factors for arsenic, lead, and selenium indicated considerable contamination. In view of these findings remediation methods must be adopted to safeguard the communities. The data will be useful for future monitoring of heavy metal exposure in the communities and to assess the impact of the ongoing crude oil drilling activity on the environment

Scaling up community-based services and improving quality of care in the state psychiatric hospitals: the way forward for Ghana

Objective: This paper aims to explore the options available for developing community-based care and improving the quality of care in psychiatric hospitals in Ghana. Method: Semi-structured interviews (SSIs) and focus group discussions (FGDs) were conducted with a cross-section of stakeholders including health professionals, researchers, policy makers, politicians, users and carers. The SSIs and FGDs were recorded digitally and transcribed verbatim. Apriori and emergent themes were coded and analysed with NVivo version 7.0, using a framework analysis. Results: Psychiatric hospitals in Ghana have a mean bed occupancy rate of 155%. Most respondents were of the view that the state psychiatric hospitals were very congested, substantially compromising quality of care. They also noted that the community psychiatric system was lacking human and material resources. Suggestions for addressing these difficulties included committing adequate resources to community psychiatric services, usingpsychiatric hospitals only as referral facilities, relapse prevention programmes, strengthening psychosocial services, adopting more precise diagnoses and the development of a policy on long-stay patients. Conclusion: There is an urgent need to build a credible system of community-based care and improve the quality of care in psychiatric hospitals in Ghana.Key words: Psychiatric hospital; Community psychiatry; Psychosocial services; Low and middle-income countries; Ghan

A novel ruthenium-silver based antimicrobial potentiates aminoglycoside activity against Pseudomonas aeruginosa

The rapid dissemination of antibiotic resistance combined with the decline in the discovery of novel antibiotics represents a major challenge for infectious disease control that can only be mitigated by investments in novel treatment strategies. Alternative antimicrobials, including silver, have regained interest due to their diverse mechanisms of inhibiting microbial growth. One such example is AGXX, a broad-spec­trum antimicrobial that produces highly cytotoxic reactive oxygen species (ROS) to inflict extensive macromolecular damage. Due to the connections identified between ROS production and antibiotic lethality, we hypothesized that AGXX could potentially increase the activity of conventional antibiotics. Using the gram-negative pathogen Pseudomonas aeruginosa, we screened possible synergistic effects of AGXX on several antibiotic classes. We found that the combination of AGXX and aminoglycosides tested at sublethal concentrations led to a rapid exponential decrease in bacterial survival and restored the sensitivity of a kanamycin-resistant strain. ROS production contributes significantly to the bactericidal effects of AGXX/aminoglycoside treatments, which is dependent on oxygen availability and can be reduced by the addition of ROS scaveng­ers. Additionally, P. aeruginosa strains deficient in ROS detoxifying/repair genes were more susceptible to AGXX/aminoglycoside treatment. We further demonstrate that this synergistic interaction was associated with a significant increase in outer and inner membrane permeability, resulting in increased antibiotic influx. Our study also revealed that AGXX/aminoglycoside-mediated killing requires an active proton motive force across the bacterial membrane. Overall, our findings provide an understanding of cellular targets that could be inhibited to increase the activity of conventional antimicrobial

Scaling up community-based services and improving quality of care in the state psychiatric hospitals: the way forward for Ghana

Objective: This paper aims to explore the options available for developing community-based care and improving the quality of care in psychiatric hospitals in Ghana. Method: Semi-structured interviews (SSIs) and focus group discussions (FGDs) were conducted with a cross-section of stakeholders including health professionals, researchers, policy makers, politicians, users and carers. The SSIs and FGDs were recorded digitally and transcribed verbatim. Apriori and emergent themes were coded and analysed with NVivo version 7.0, using a framework analysis. Results: Psychiatric hospitals in Ghana have a mean bed occupancy rate of 155%. Most respondents were of the view that the state psychiatric hospitals were very congested, substantially compromising quality of care. They also noted that the community psychiatric system was lacking human and material resources. Suggestions for addressing these difficulties included committing adequate resources to community psychiatric services, using psychiatric hospitals only as referral facilities, relapse prevention programmes, strengthening psychosocial services, adopting more precise diagnoses and the development of a policy on long-stay patients. Conclusion: There is an urgent need to build a credible system of community-based care and improve the quality of care in psychiatric hospitals in Ghana