As a program designed for bridging research to development outcome, the CPWF considers regular reflection, learning and adaptive management as crucial elements in the implementation of the basin programs. Reflection implies that the project teams and key stakeholders take stock of what is going on in the project in terms of the science and the process and revisit basic assumptions that underpinned their research. Such reflection provides opportunities for the learning which directs adaptive management. In 2012, basin level reflection took the form of a Field Tour, Learning Events, and a Science Workshop, held between 29 June and 5 July.

Para evaluar el efecto de dos estrategias alimentarias y presencia de sustrato para perifiton sobre el perfil de ácidos grasos, características sensoriales y microbiológicas en filetes de tilapia y bocachico, se realizó un policultivo bajo un diseño factorial 2x2 con tres réplicas. El primer factor, A1: alimento con 20% de proteína bruta (PB) y A2: alimentación con niveles decrecientes de PB, (38, 32, 24 y 20%). El segundo factor B1: presencia y B2: ausencia de sustrato para perifiton. Al final de un periodo de cultivo de ocho meses fueron analizados los filetes de las dos especies. Las muestras cumplieron con los parámetros microbiológicos del INVIMA. No hubo diferencias significativas sensoriales entre tratamientos. En tilapia, la estrategia alimentaria tuvo efectos sobre el perfil de ácidos grasos, no en bocachico. En bocachico se encontraron relaciones &#937;-6/&#937;-3 de 0,7±0,12, en tilapia de 3,9±1,2 y en perifiton de 0,7±0,007. Por la relación &#937;-6/&#937;-3 menor a 1 y la presencia de DHA y EPA, el bocachico reúne características para ser identificado como un alimento funcional. El perifiton presentó niveles altos de ALA, siendo una fuente apropiada para peces. Tilapia tiene más alta relación de &#937;-6: &#937;-3, pero con adecuados niveles de DHA y EPA.<br>Para avaliar o efeito de duas estratégias alimentarias e a presença de substrato para perifiton no perfil dos ácidos graxos, características sensoriais e microbiológicas dos files de tilápia e bocachico, foi feito um policultivo sob um desenho fatorial 2x2 com três repetições. O primeiro fator com dois níveis, A1: alimento de 20% de proteína bruta (PB) e A2: alimentação com níveis decrescentes de PB, (38, 32, 24 y 20%). O segundo fator B1: presença e B2: ausência de substrato para perifiton. No final do cultivo de oito meses, foram analisados os filés das duas espécies. Todas as amostras tiveram os parâmetros microbiológicos segundo o INVIMA. No painel sensorial não se encontraram diferenças significativas entre os tratamentos. Em tilapia, a estratégia alimentaria teve efeitos no perfil de ácidos graxos, mas não em bocachico. Em bocachico se encontraram relações &#937;-6/&#937;-3 de 0,7±0,12, em tilapia de 3,9±1,2 e no perifiton de 0,7±0,007. Pela relação &#937;-6/&#937;-3 e a presença de DHA e EPA, o bocachico tem características para ser identificado como um alimento funcional. O perifiton apresentou níveis altos de ALA, sendo uma fonte apropriada para peixes. Tilápia tem mais alta relação de &#937;-6/&#937;-3, mas com bons níveis de DHA e EPA.<br>To evaluate the effect of two feeding strategies and the presence of substrate for periphyton on the fatty acid profile, sensory and microbiological characteristics in tilapia and bocachico fillets, we performed a polyculture under a 2x2 factorial design with 3 replicates. The first factor with two levels, A1: food with 20% crude protein &#91;CP&#93; and A2: a meal plan with decreasing levels of PB, (38, 32, 24 and 20%). The second factor B1 substrate and B2 absence of substrate for periphyton. At the end of the cultivation of eight months were analyzed both fish fillets. All samples met the standard microbiological parameters as INVIMA. The sensory panel found no significant differences between treatments. There was no effect of the presence of substrate on fatty acid profile in fish. In tilapia, the feeding strategy had effect on fatty acid profile, not in bocachico. &#937;-6/&#937;-3 ratio was 0.7 ± 0.12 in bocachico, in tilapia was 3.9 ± 1.2 and 0.7 ± 0.007 for periphyton. &#937;-6/&#937;-3 ratio was less than 1 and the presence of DHA and EPA, bocachico can be identified as a functional food. Periphyton showed high levels of ALA, which makes it an appropriate source for fish. Tilapia has a higher ratio of &#937;-6/&#937;-3, but with good levels of DHA and EPA.

A new kind of solid phase extraction (SPE), which we named in situ surfactant-based solid phase extraction (ISS-SPE), represents a simple, selective and rapid method for preconcentration and determination of manganese from food and water samples. This method has distinct advantages: extraction times are short and recoveries are high; further, we can see formation of fine particles of large specific surface and their good dispersion in the solution. In this work, a small amount of cationic surfactant, n-dodecyltrimethylammonium bromide (DTAB) was injected into the water sample containing Mn ions, which were complexed by 1-(2-pyridylazo)-2-naphthol (PAN). After shaking, a little volume of NaPF6 as an ion-pairing agent was added into the solution by a microsyringe. After preconcentration, the settled phase was dissolved in a specific volume of ethanol and then aspirated into the flame atomic absorption spectrometer by using a homemade microsample introduction system. The effective parameters such as pH, concentration of surfactant, concentration of chelating agent, concentration of ion-pairing agent and effect of salt concentration were optimized by a fractional factorial design to identify the most important parameters and their interactions, and central composite methodology was used to achieve the optimum point of effective parameters to the response. Under the optimum conditions, preconcentration of 10 ml of the sample solution permitted detection of 0.88 μg l−1 with enhancement factor of 45.6, and the relative standard deviation (RSD) for five determinations of Mn ions was 3.5%. The developed method was applied to the determination of trace manganese in various real samples with satisfactory results.

Freeze-dried aqueous phenolic extracts with possible application as natural antioxidant functional food ingredients were prepared from marama bean seed coats by extracting with water. Phenolic acids, flavonoids and proanthocyanidins in the extracts were characterised by HPLC/MS. The major flavonoids were the flavanols methyl (epi)afzelechin-3-O-gallate (40%) and methyl (epi)catechin-3-O-gallate (28%), and the major phenolic acid was gallic acid (10%). Proanthocyanidins in the extracts were predominantly prodelphinidins composed of epicatechin-3-O-gallate and epigallocatechin present as major terminal and extension units and epigallocatechin-3-O-gallate and epicatechin present as minor extension unit constituents. The polymer structure was found to be unique compared with other legumes because of the high percentage of galloylated units. Extracts showed a high DPPH free radical scavenging activity (707 μmol TE g−1), protective effect against AAPH-induced human red blood cell haemolysis and copper-catalysed human LDL oxidation suggesting that the extracts may have potential health benefits.

Text retained for oral presentation during the 2012 African Econometrics Society (AES) Conference to be held in Kampala, from 25 to 27 of July 2012 | Economics is all about rationality in resource allocation rather than greedy maximization of profits. Water suppliers enjoy high water productivities under drought conditions but are unable to ensure supply sustainability to the expense of water users. This study attempted to explain food shortage in the water scarce Muooni Catchment in the course of climate change. It used operational research, and particularly hydro-economic inventory models to address three specific questions: (i) what anthropogenic and environmental factors undermine water storage in Muooni Dam? (ii) to what extent do fluctuations of the active water storage capacity of Muooni Dam affect agricultural water productivity and food security in the catchment? (iii) how can farmers optimize their water demands and supplies in this catchment under fluctuating rainfall regimes? Hydro-economic inventory models were specifically used to evaluate farmers’ water Economic Order Quantity (EOQ), Limit Average Cost (LAC) and Minimum Efficient Scale (MES). This approach enabled useful recommendation on the rationalization and optimization of crop water requirements and crop yields under three different rainfall regimes: Above Normal (ANOR), Normal (NOR), and Below Normal (BNOR) [JEL Classification Number: Q 25 ].

The aim of the present study was to assess the influence of pH (3, 7 and 9) as well as ionic strength of NaCl (0mmol/l, 100mmol/l, 200mmol/l and 400mmol/l) on the retention and release characteristics of diacetyl and (−)-α-pinene in oil-in-water (o/w) emulsions prepared with dried egg yolk (DEY) or starch sodium octenylsuccinate (SOE). Increase of pH from 3 to 9 progressively enhanced retention of diacetyl in emulsions prepared with both DEY and SOE. Whereas, in samples flavoured with (−)-α-pinene, the highest and lowest retention time-courses were detected at pH 9 and pH 7 as well as pH 7 and pH 3 regarding emulsions prepared with DEY as well as SOE, respectively. With increasing salt concentration, the retention of diacetyl was decreased, irrespectively of the applied emulsifier type, whereas generally opposite effects were observed in the case of (−)-α-pinene. The parameters of release characteristics i.e., release rate constants (k) and release mechanism factors (n), were calculated using Avrami’s equation. ANOVA revealed significant effects (p<0.001) of pH and NaCl concentration on k parameters, whereas relationship between applied environmental conditions and n factors was dependent on hydrophobicity of the odourant. Sensory evaluation revealed higher correlation values between odour intensity and aroma compound concentration in emulsions aromatized with (−)-α-pinene than with diacetyl.