Evaluating a group-based intervention to improve the safety of meat in Bodija Market, Ibadan, Nigeria

We evaluated a group-based, participatory training intervention to improve food safety among meat processors and retailers in Bodija Market, Ibadan, Nigeria. An interactive training workshop was held for Butchers Associations' representatives who were selected to pass on information and training to their group. Meat hygiene knowledge, attitude and practice was assessed before attending the workshop and afterwards (n?=?63). It was also assessed for those who did not attend the workshop (n?=?68) but were intended recipients of training through their association. Microbiological quality of meat was assessed before and after the workshop (n?=?400 samples). After the workshop, participants significantly improved knowledge, attitude and practice in key food safety aspects; specifically, understanding sources of contamination and food-borne diseases, use of bleach and disinfectant and hand washing. Participants also shared information with an average of 18 other group members and improvements were seen in group members who did not attend the workshop but received training through their Butchers Association. Microbiological quality of meat sold also significantly improved after the intervention. In conclusion, participatory, group-based methods targeted at meat processors and retailers can improve meat hygiene knowledge, attitude and practice as well as the microbiological quality and hence safety of meat.     

Properties of strand boards with uniform and conventional vertical density profiles

Randomly oriented strand boards with both uniform and conventional vertical density profiles (VDP) were manufactured, and their properties were evaluated and compared. The bending modulus of elasticity (MOE) of conventional strand boards was predicted using the laminated beam theory and the MOE-density regression equation from the uniform strand boards. The results showed that the predicted MOE of conventional strand boards was close to the measured MOE with a difference of less than 10%. The internal bond strength values of uniform strand boards were found to be higher than conventional strand boards while no significant difference was found in water-related properties. Compared with uniform strand boards, MOE values of conventional strand boards were improved only at higher density level. About 10% of improvement in MOE can be obtained for the strand boards investigated by manipulating the VDP. Steeper VDPs were predicted to be required for thinner boards than for thick boards in order to achieve the same improvement in MOE.     

Using a Numerical Model to Track the Discharge of a Wastewater Treatment Plant in a Tidal Estuary

Along the coast of Maine, USA, there are numerous wastewater treatment plants that discharge their treated effluents into a river estuary which is shared by commercial fishing and shellfish harvesting. Occasionally, there can be failures or bypasses of treatment plants that lead to untreated or partially treated sewage flowing into shellfish harvesting waters. To prevent any toxic contamination of harvested shellfish, a prohibitive zone is established around the treatment plant where shellfish harvesting is prohibited. The U.S. Food and Drug Administration has conducted numerous dye studies on both coasts of the USA to determine these prohibitive zones, based on the guidelines of the National Shellfish Sanitation Program. In May 2010, the FDA conducted such a dye study at the Yarmouth, Maine wastewater treatment plant. The results are compared with a numerical coastal model that provides the velocity field for the currents around the treatment plant. This model includes a diffusion equation to simulate dye dispersion from a point source which is used to determine the prohibitive zone. The numerical model shows good correlation with the FDA dye study report and establishes a prohibitive zone for commercial harvesting in keeping with that of the FDA study. The benefits of the numerical model include sampling at thousands of locations simultaneously, seasonal changes in river volumes, and changes in plant discharge volumes.     

Effects of temperature and photoperiod on hemolymph vitellogenin levels during spawning events of the blue crab,Callinectes sapidus,in captivity

Vitellogenesis is the process of production and uptake of vitellogenin (VtG), the precursor of vitellin (VT = yolk protein), for ovarian development. In Callinectes sapidus, hemolymph VtG levels are positively correlated with ovarian development. We aimed to develop an invasive tool to monitor ovarian development in order to predict spawning. The present study determined the effects of photoperiod and temperature conditions on levels of hemolymph VtG of the females in captivity kept in a closed recirculating system. Hemolymph VtG levels measured using a competitive ELISA correlates positively with temperature (21° versus 11°C) but are negatively correlated with photoperiod (0L:24D and 8L:16D versus 16L:8D and 24L:0D). Also, heavier (larger) females contain more VtG in their hemolymph and produce greater numbers of larvae. At 21°C, the VtG levels show high individual variations and continuously change over time, indicating that VtG production and uptake by ovary may be continuous and dynamic over multiple spawning events in C. sapidus. Microsatellite analysis of these females reveals a great diversity within and between the batches, implying that resident C. sapidus populations in the Chesapeake Bay are genetically dynamic. Such a great genetic diversity could be responsible for the high variation in VtG levels in these females.     

Determination of elements removal in different harvesting scenarios of Scots pine (Pinus sylvestris L.) stands

Increasing demand for renewable energy and limiting CO₂ emissions have stimulated much interest in wood-based biofuels. Unfortunately, expanding the utilization of forest biomass may cause nutrient depletion in forested environments. This study investigates the element content from various parts of the tree. Comparisons were made between different harvesting scenarios and their impact on the amount of nutrients removed from the forest environment. The harvesting scenarios were: stem-only harvesting (SOH), branch and stem harvesting (BSH), and two variants of whole-tree harvesting (WTH). The elements taken into account were: carbon (C), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), sulphur (S), copper (Cu), iron (Fe), nickel (Ni), manganese (Mn), zinc (Zn), cadmium (Cd), chromium (Cr) and lead (Pb). To make the results comparable, the same amount of removed biomass was taken into calculation. The differences between harvesting scenarios were significant. The amounts of removed elements formed similar pattern: the lowest level was found in SOH, average in BSH, and highest in both variants of WTH. This confirms that the application of WTH is connected with increased risk of nutrient depletion, even when the volume of harvest would be equal to other variants.     

Land Cover Change Impacts on Beef Cattle Productivity under Changing Climate: Case of Ilemela and Magu Districts,Tanzania

The study focused on contributing to the spatial knowledge of the impacts of land cover changes on beef cattle production under a changing climate in rangelands of the Lake Victoria Basin (LVB), so as to establish a strategy for improving beef cattle production in the area. We used supervised classification of satellite imagery to analyze land cover changes between the years 1980–2000 and 2000–2010. Results revealed that for the periods 1980–2000 and 2000–2010, settlements increased by 1% and 8%, and cultivated area increased by 0.58% and 0.30%, respectively. Riverine vegetation declined by 0.26% and increased by 0.16%, and woodlands declined by 6% and 13% respectively. The trend of beef cattle numbers against rainfall and pasture area (riverine vegetation and woodland) over the study period 1980–2010 showed a non-significant trend of increasing rainfall in the study area. In Ilemela District, pasture area and beef cattle numbers declined by 33% and 4% respectively. In Magu District, beef cattle numbers increased by 64% and pasture area declined by 84%. This implies that the effect of urbanization is more severe in Ilemela than in Magu District. Land use planning, enhancing of mixed crop-livestock farming systems, intensification of livestock practices, forage conservation, planting of fodder trees, and matching of cattle numbers with pasture availability are recommended. In addition, education is needed on effective cattle farming as a strategy for improving beef cattle production in the face of land cover changes due to climate variability in the area.     

Germplasm sources of protective glandular leaf trichomes of hop (<Emphasis Type="Italic">Humulus lupulus</Emphasis>)

We report here that small but numerous foliar glands are present near the base of the abaxial leaf blades of hop (Humulus lupulus L.) at about 2.6 times the density found in the more distal regions, and this concentration of glands appear to protect the basal region from damage by insects. Distinctive wild taxa of H. lupulus are native to distinctive regions of the north temperate world. The much higher presence of protective glands in the three native North American Humulus taxonomic varieties in comparison with the varieties native to Europe and Asia suggests specialized leaf feeders in North America have been responsible for the evolution of greater gland density. Commercial domesticated hop cultivars trace most of their germplasm to the European hop (H. lupulus var. lupulus), which possesses a much lower concentration of leaf glands than the native hops of all other regions of the world, and therefore is likely relatively susceptible to damage. We suggest that breeding for increased density of protective foliage glands may be a non-chemical way of alleviating foliar feeding damage in cultivated hops.     

Perchlorate Distribution, Excretion, and Depuration in Prairie Voles and Deer Mice

A study on perchlorate distribution was conducted in male adult prairie voles (Microtus ochrogaster). Excretion via urine was the major pathway for perchlorate fate in the body, with the highest concentrations of perchlorate detected in urine after exposure to perchlorate through drinking water [250 μg/ml Mg(ClO₄)₂], and an average of 34% and 88% of perchlorate intake recovered in urine in the 4- and 8-h exposure groups, respectively. Perchlorate mass in kidney, thyroid, blood, and urine were related to perchlorate intake (254.5–2687.7 μg). Perchlorate excretion and depuration patterns via urine were tested further using male adult deer mice (Peromyscus maniculatus). Animals were exposed to perchlorate through dosed drinking water (0, 17, 165, and 1600 ng/ml). Perchlorate concentrations in urine showed a significant difference among the three dosed groups during a 28-day exposure period. However, no difference was found in urine among the three dosages in terms of mass percentage of perchlorate intake from water at each sampling time over the 28-day exposure period. Both concentrations of perchlorate and mass percentage in urine reached a steady state after 1 day in all treatments. On average 46%, 46%, and 61% of perchlorate intake from water was recovered in urine over the exposure period in high, medium, and low dose groups, respectively. Including perchlorate consumption from rodent chow (1.44 ng/g), less than 46% of perchlorate intake was recovered in urine in the high and medium dose groups, and <61% in the low dose group. Three parameter first-order decay models fit the depuration curve very well, with r?>?0.99 in both the low and high dose groups; half-lives of perchlorate in deer mice were estimated as 9.12 and 7.25 h in the low and high dose groups, respectively. Endogenous generation of perchlorate and/or some degree of retention or metabolism of perchlorate may occur in deer mice, based in part on the uncompleted mass balance in the excretion and depuration experiments. The data reported herein should provide additional insight for perchlorate fate determination in animals and humans and valuable information for perchlorate risk assessment in the environment, especially wildlife.     

Texture and sesquioxide effects on water-stable aggregates and organic matter in some tropical soils

Many tropical soils include sesquioxides, which influence the stability of soil organic matter (OM) and aggregation to an extent that is not fully characterized. The present study was carried out on a range of 18 topsoil samples (0–10 cm) from low-activity clay (LAC) soils from sub-Saharan Africa and Brazil, and aimed: (i) at characterizing the size distributions of water-stable aggregates and organic constituents, (ii) at studying how these distributions were affected by texture and sesquioxides, and (iii) how they interacted.The distributions of stable aggregates were generally dominated by macroaggregates (> 200 μm), and those of organic constituents by fine OM (< 20 μm). Aggregation was not clearly affected by soil texture, while total soil carbon (Ct) and the amount of carbon (C) as fine OM increased with soil content in clay plus fine silts (< 20 μm). Stable macroaggregation correlated with Ct and with C amount as fine OM, but each of them correlated more closely with citrate-bicarbonate-dithionite-extractable aluminium (Al), which was not expected. Stable macroaggregation also correlated with C amounts as coarse- and medium-sized OM (> 200 and 20–200 μm, respectively), but each of them correlated more closely with oxalate-extracted Al. These results suggested that for the LAC tropical soils under study OM and aggregate stability depended closely on Al-containing sesquioxides, on Al-substituted crystalline hematite and goethite especially. These sesquioxides also seemed to play a dominant role in the relations between aggregation and OM. As far as soils rich in sesquioxides are concerned, this confirmed that OM is not the main aggregating agent, and suggested that physical protection within aggregates is not necessarily the main mechanism for OM stabilization. However, as soil sesquioxide content cannot be managed easily, the effect of land use on soil OM and aggregation was determinant at the local scale: indeed, for a given location, stable macroaggregation, Ct and C amount as fine OM generally decreased with land use intensification (i.e. cultivation, tillage, reduced surface cover).