Farm level adoption decisions of soil and water management technologies in semi-arid Eastern Kenya

In this paper the conceptual framework of individual farmers' adoption decisions of new agricultural technologies is used to identify factors that influence adoption modified fanya juu terraces in semi-arid eastern Kenya. The adoption decision model was specified using farm and farmers' characteristics and technology characteristics though likely to influence farmers' adoption behaviour. To test intensity of adoption a Torbit model was specified and estimated. Results of logit regression analysis reveal that access to markets, education, costs, technology attributes, labour, credit and risk preferences significantly influenced adoption decisions. Results from the estimated intensity of adoption model (tobit) show that variation in the proportion of land with technology was significantly influenced by age and level of education of the household head, access to markets, technology attributes, credit, off-farm income and risks.Logit analysis, Tobit analysis, modified terraces, adoption, Farm Management, Land Economics/Use,

Recognizing and realizing the potential of organic agriculture in Kenya

Formal organic agriculture in Kenya dates back to the early eighties when the first pioneer organic training institutions were established. During the same period, a few horticultural companies started growing organic vegetables for export. Initial efforts to promote organic agriculture in Kenya were made by rural development non-governmental organizations (NGOs), faith based organizations and community based organizations (CBOs). They seek to help rural farmers in addressing the issue of declining agricultural productivity (especially the degradation of soils and natural resource base), high poverty incidences, food insecurity and low incomes which pre-vented farmers from assessing high costs inputs. Currently Kenya has five major players in organic agriculture namely Kitale-based Manor House Agricultural Center, Baraka College in Molo, the Sustainable Agriculture Community Development Pro-gram in Thika, the Kenya Institute of Organic Farming (KIOF), a training center on the outskirts Kenya’s capital Nairobi, and the Association for Better Land Husbandry (ABLH), headquartered in Nairobi. The organic sector is relatively small; however, it is growing very fast, led mainly by NGOs and private sector (companies growing organic produce for export). Exports of organic products have been taking place for the last two decades, mainly with vegetables and fruits produced on large scale farms. Over the years exports have developed beyond vegetables and fruits to include other prod-ucts such as essential oils, dried herbs and spices as well as products for the cos-metic and pharmaceutical industries which are more often produced by smallholders. Currently, there are five international certifiers operating in Kenya, namely: the Soil Association (SA), EcoCert International; IMO (Institute for Market Ecology); USDA’s (United States Department of Agriculture) National Organic Programme (NOP) and Bio Suisse

The climatological relationships between wind and solar energy supply in Britain

We use reanalysis data to investigate the daily co-variability of wind and solar irradiance in Britain, and its implications for renewable energy supply balancing. The joint distribution of daily-mean wind speeds and irradiances shows that irradiance has a much stronger seasonal cycle than wind, due to the rotational tilt of the Earth. Irradiance is weakly anticorrelated with wind speed throughout the year ($-0.4 \lesssim \rho \lesssim -0.2$): there is a weak tendency for windy days to be cloudier. This is particularly true in Atlantic-facing regions (western Scotland, south-west England). The east coast of Britain has the weakest anticorrelation, particularly in winter, primarily associated with a relative increase in the frequency of clear-but-windy days. We also consider the variability in total power output from onshore wind turbines and solar photovoltaic panels. In all months, daily variability in total power is always reduced by incorporating solar capacity. The scenario with the least seasonal variability is approximately 70%-solar to 30%-wind. This work emphasises the importance of considering the full distribution of daily behaviour rather than relying on long-term average relationships or correlations. In particular, the anticorrelation between wind and solar power in Britain cannot solely be relied upon to produce a well-balanced energy supply.Comment: 19 pages, 19 figures, accepted for publication in Renewable Energy. Text updated to match accepted version (one footnote added, some references corrected

RRS Discovery Cruise 248, 07 Jul-10 Aug 2000. A multidisciplinary study of the environment and ecology of deep-water coral ecosystems and associated seabed facies and features (The Darwin Mounds, Porcupine Bank and Porcupine Seabight)

RRS Discovery Cruise 248 aimed to carry out a multidisciplinary study of the environment and ecology of deep-water coral ecosystems and associated seabed features in the northeast Atlantic. The study was primarily focused on the Darwin Mounds area, northern Rockall Trough (59° 49’N, 07° 22’W), but also examined a number of sites in the Porcupine Seabight area. The cruise was divided into two legs (Govan-Stornoway, 8 Jul-21 Jul 2000; Stornoway-Southampton, 22 Jul-10 Aug 2000). Leg 1 focused on the ecology of the Darwin Mounds area, with seabed photographic surveys (SOC SHRIMP system), coring (Box and Multiple cores) and trawling (Agassiz) forming the main activities. Leg 2 began with detailed geological investigations of the Darwin Mounds area, concentrating on piston coring and sidescan sonar surveys. Leg 2 concluded with combined ecological and geological studies of carbonate mound sites on the Porcupine Bank and in the Porcupine Seabight.Observations in the Darwin Mounds area confirmed the common occurrence of deep-water corals on these Mounds. The mounds themselves do not appear to be carbonate formations but may be better characterised as sand volcanoes. Numerous xenophyophores were observed in association with the mounds; however, no live specimens were recovered in any of the samples collected. Sidescan sonar images and seabed photography both suggested that the Darwin Mounds area had been subject to considerable commercial trawling with resultant apparent damage to the deep-water coral ecosystems.The various operations undertaken in the Porcupine Seabight area were also successful in imaging giant carbonate mounds and their associated coral communities with both sidescan sonar and seabed photography, and in recovering biological sample material from these areas. In common with the Darwin Mounds area, the observations made suggested that deep-water fishing impacts on coral ecosystems were also evident in this region

Using the Twentieth Century Reanalysis to assess climate variability for the European wind industry

We characterise the long-term variability of European near-surface wind speeds using 142 years of data from the Twentieth Century Reanalysis (20CR), and consider the potential of such long-baseline climate data sets for wind energy applications. The low resolution of the 20CR would severely restrict its use on its own for wind farm site-screening. We therefore perform a simple statistical calibration to link it to the higher-resolution ERA-Interim data set (ERAI), such that the adjusted 20CR data has the same wind speed distribution at each location as ERAI during their common period. Using this corrected 20CR data set, wind speeds and variability are characterised in terms of the long-term mean, standard deviation, and corresponding trends. Many regions of interest show extremely weak trends on century timescales, but contain large multidecadal variability. Since reanalyses such as ERAI are often used to provide the background climatology for wind farm site assessments, but contain only a few decades of data, our results can be used as a way of incorporating decadal-scale wind climate variability into such studies, allowing investment risks for wind farms to be reduced.Comment: 18 pages, plus 4 page supplementary information included here as Appendix D. This is the authors' corrected version, matching the content of the version accepted by Theoretical and Applied Climatolog

Non-Canonical Targets, Reaction Kinetics, And Cellular Potency Of Amino Acid-Linked Platinum(ii) Compounds

DNA serve as an ideal target where drugs such as cisplatin (cisPt) bind and exert their anticancer activities. CisPt is known to preferentially coordinate with DNA leading to formation of cisPt-deoxyguanosine (dGuo) adducts. The adducts distort the DNA structure and contribute to inhibition of DNA-mediated cellular functions and ultimately cancer cell death. Despite its utilization as an anticancer drug, cisPt has a number of drawbacks, which include toxic side effects and cellular resistance. Resistance occurs through processes such as repair of damaged DNA and inactivation of cisPt present in the cell. To overcome these challenges, the aim of this thesis work was to synthesize and investigate compounds that coordinate to different sites from those targeted by cisPt, including sites found in RNA. In this highly collaborative dissertation project, amino acid-linked platinum(II) compounds were synthesized and studied as alternatives to cisPt. The reactivity preferences of these compounds towards DNA/RNA nucleosides and oligonucleotides were determined through pseudo-first-order kinetics. The products formed by the reactions of amino acid-linked platinum(II) compounds with DNA and RNA were studied by electrospray ionization mass spectrometry (ESI-MS) to determine the type of adducts formed by the compounds. NMR spectroscopy was used to determine the non-canonical adducts formed by the compounds that include platination of the N1, N3, or N7 positions of RNA adenosine (Ado) residues. Features of amino acid-linked platinum(II) compounds that impact the glycosidic bond stability of Ado residues were explored by using tandem mass spectrometry in collaboration with the Rodgers laboratory. Furthermore, cytotoxicity assays and inductively coupled plasma mass spectrometry (ICP-MS) were used to determine the potency and accumulation of the compounds in cancer cells. Altogether, the unique characteristics of the amino acid-linked compounds such as altered reactivity preferences, formation of adducts at non-canonical residues, destabilization of glycosidic bonds, selective potency, and higher accumulation in cancer cells are important features that could circumvent drug resistance faced by the currently available platinum-based drugs

Rising populations without sustainable food systems will heighten Africa’s infectious disease burden

Africa’s unprecedented growth in human population and urbanisation will likely exert more pressure on ecosystems, mainly through the transformation of food systems. These changes would heighten the risk of many infectious diseases, including those shared between humans and animals. Identifying sustainable food production systems in line with the One Health framework is therefore essential to pre-empt future pandemic, epidemic or endemic diseases

RRS "Charles Darwin" Cruise 150, 22 Aug - 15 Sep 2003. Benthic ecology and biogeochemistry of the Pakistan Margin

RRS Charles Darwin cruise 150 forms part of a larger programme of research (“Benthic processes in the Arabian Sea: interrelationships between benthos, sediment, biogeochemistry and organic matter cycling”, NER/A/S/2000/01280), focusing on the benthic biogeochemistry of the Pakistan Margin, that includes four cruises in total (CD145, 146, 150 and 151). The primary objectives of the present cruise were: a) to revisit a series of five previously established study sites (A140, A300, A950, A1200 and A1850) spanning the Arabian Sea oxygen minimum zone (OMZ) as it impinges on the seabed at the Pakistan Margin; b) to assess the chemical oceanography of the water column overlying these sites, through CTD sensor profiles and chemical determinations on water bottle samples from both the CTD and BBLS; c) to initiate a programme of detailed seabed sampling at these sites to determine a suite of biological, chemical and biogeochemical parameters using a Megacorer and a multicorer; d) to assess and sample the megabenthos of these sites by the combined use of trawling (Agassiz trawl) and seabed photography (WASP); e) as possible, to carry out similar operations at a site located at a depth between A300 and A950; f) as possible, to provide additional general characterization of the seabed in the area of these sites using acoustic remote sensing (EM12 and 3.5 kHz ) and seabed imagery (WASP ).The cruise successfully achieved all of the planned objectives. The effort of assessing the science of the cruise will take many months of work ashore. Of those parameters that could be initially assessed onboard there was little indication of major change between cruises 145 and 150, other than in the OMZ itself. Minimum oxygen values encountered during cruise 145 were around 400m, but during the present cruise were in the 150-200m range. If a value of 0.5 ml/l is used as a boundary, then it had shallowed from c. 180m (CD145) to c. 80m (CD150). There also appeared to be some elevation of the lower boundary of the OMZ, although this was less marked

RRS "Discovery" Cruise 282, 30 Jun - 01 Aug 2003. The environment and ecology of Seine and Sedlo Seamounts, NE Atlantic

The general aim of the cruise is to undertake a range of physical, chemical and biological investigations on and around Seine and Sedlo Seamounts. Specific objectives for the cruise included: a) the recovery of two current meter moorings from Seine Seamount (originally deployed from FS Poseidon in March 2004); b) to make underway observations of upper water column currents and zooplankton migrations (using ADCPs and 10 kHz echosounder); c) to assess water column hydrography, primary production and biogeochemistry through deployments of a CTD and water bottle rosette; d) to assess the biochemistry and biogeochemistry of suspended particulate matter by the use of SAPS (stand alone pumping system); e) to investigate the taxonomy, ecology and biogeochemistry of zooplankton communities using a multiple opening and closing net system (MOCNESS); f) to make photographic (stills and video) observations of the seabed and its larger fauna (megabenthos) using the SOC SHRIMP system (Seabed High Resolution Imaging Platform); and g) to carry out a suite of seabed sampling (coring, dredging and trawling) to investigate the taxonomy, ecology and biogeochemistry of seabed communities. The latter objective was immediately precluded by the unavailability of either the coring or trawl winches for the duration of this cruise. Only limited SHRIMP operations and no MOCNESS operations were undertaken at Sedlo Seamount as a result of the failure of the electro-optical tow winch. All other cruise objectives were fully achieved