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131.
Nyangaga Julius N. Grace Delia Kimani Violet Kiragu Monica W. Langat Alfred K. Mbugua Gabriel Mitoko Grace Kangethe Erastus K. 《Tropical animal health and production》2012,44(1):47-51
A study was undertaken to investigate and mitigate the risk from zoonotic Cryptosporidium associated with dairy farming in Dagoretti division, Nairobi, Kenya. Outcome mapping (OM), a relatively new tool for planning and evaluation, was used to foster and then monitor changes in farmer management of health risks. Elements of the OM framework, including the vision, mission and expected progress markers, were developed in participatory sessions and a set of progress markers was used for monitoring behaviour change in farmers participating in the project (the boundary partners). Behaviour change (the outcome challenge) was supported by a range of awareness and educational campaigns, working with strategic partners (extension agents and administrative leaders). The farmers the project worked with made considerable progress according to the markers; they demonstrated an understanding of cryptosporidiosis, established or maintained clean and well drained cattle sheds, and took conscious effort to reduce possible infection. Farmers who did not participate in the project (non-contact farmers) were found to be less advanced on the progress marker indicators. Non-contact farmers who carried out risk-reducing practices had done so independently of the project team. The administration leaders, as strategic partners, had a positive attitude towards the project and confidence in their ability to support project objectives. The study demonstrates the utility of OM in helping to identify and support behavioural change. 相似文献
132.
Christoph Buksnowitz Ulrich Müller Robert Evans Alfred Teischinger Michael Grabner 《Wood Science and Technology》2008,42(2):95-102
The orientation of the tracheid cells with respect to the stem axis (grain angle, spiral grain) exerts a strong influence
on numerous material properties. Therefore, several methods have been developed to assess this wood anatomical feature. The
current study compares SilviScan spiral grain measurements, which uses X-ray diffractometry, with direct goniometer readings.
The correlation between these two methods yielded an r2 of 0.874 and a root mean square error of prediction (RMSEP) of 1.21 clearly demonstrating that X-ray diffractometry can provide
accurate and rapid information on the grain orientation in Norway spruce (Picea abies (L.) Karst.) or similar structured softwoods. 相似文献
133.
Alfred G. O. Dixon Malachy O. Akoroda Richardson U. Okechukwu Francis Ogbe Paul Ilona Lateef O. Sanni Chukwuma Ezedinma Jones Lemchi Gorrettie Ssemakula Marie O. Yomeni Emelike Okoro Gbassey Tarawali 《Euphytica》2008,160(1):1-13
The aim of the Integrated Cassava Project (ICP) of the International Institute of Tropical Agriculture was to pre-emptively
manage the cassava mosaic disease (CMD) to avert an imminent and increasing possible threat of the Ugandan strain of the CMD
virus of the pathogen from doing damage to the Nigerian cassava economy. The strategy was to engage in activities that would
lead to cultivar-substitution by replacing the susceptible varieties on farmers’ fields with superior genotypes that are not
only CMD resistant or tolerant but also high yielding with good dry matter content. A fast track participatory selection approach
was used in 2 years to release nine new lines in Nigeria. It was intensive and several lessons were learnt. The varieties
released after 2 years were TMS 98/0510, TMS 98/0581, TMS 97/2205, TMS 98/0505, TME 419, TMS 92/0326, TMS 96/1632, TMS 98/0002,
and TMS 92/0057. 相似文献
134.
Aissetou Dramé Yayé Alfred Oduor Ochola Sebastian Chakeredza James Aucha 《Agroforestry Systems》2017,91(5):835-845
This paper highlights the main achievements of the programme on Strengthening Africa’s Strategic Agricultural Capacity for Impact on Development (SASACID) funded by the Swedish International Development Cooperation Agency (Sida). The programme is implemented by the African Network for Agriculture, Agroforestry and Natural Resources Education (ANAFE) through 16 Pilot Institutions (PIs). It focuses on supporting agribusiness development in tertiary agricultural education and research in Africa. Under the programme, ANAFE is working towards refocusing agricultural learning and development objectives, producing contextualized learning materials, managing risk and uncertainties in agriculture, developing and reviewing curricula, retooling lecturers in pedagogy and strategizing on how best to work more closely with the private sector. The paper build on the final SASACID (2012–2014) report jointly developed through the Results-Based Management logical framework with the 16 SASACID Pilot Institutions (PIs) that met in Nairobi November 11–13, 2014. Results show that even though the PIs are at different levels of achievement over 75 % have achieved 80 % of the expected outputs. Management of scholarships for BSc and MSc students working with the private sector on risk management-related issues is among the outputs achieved by all the Pilot Institutions. Formalizing engagement with private sector through signing of Memoranda of Understanding (MoU) was reported by 25 % of the PIs working in Agribusiness through which students were supported to undertake research or internship within selected private sector firms; about 15 % got employed while others initiated their own businesses. A major output from the programme is the development and sharing of Agribusiness and Risk Management curricula frameworks for all degree levels from Diploma, BSc, MSc and PhD. Four Pilot institutions have signed MoUs with ANAFE to test the Agribusiness curricula at various levels. They are Rongo University College, Taita Taveta University College and Strathmore University (all from Kenya) and (Kenya), Mulungushi University (Zambia). The objective of this paper is to highlight ANAFE’s key achievements in transforming tertiary agricultural education and research in Africa, with specific reference to the SASACID programme. The programme was implemented from 2011 to 2015. Sixteen (16) ANAFE member institutions from 14 countries, competitively selected, implemented the SASACID programme, which focused on Agribusiness and management of risks and uncertainties in agriculture. 相似文献
135.
Christoph Buksnowitz Christoph Hackspiel Karin Hofstetter Ulrich Müller Wolfgang Gindl Alfred Teischinger Johannes Konnerth 《Wood Science and Technology》2010,44(3):389-398
Electronic speckle pattern interferometry was applied to directly measure the distribution of longitudinal, tangential, and
shear strains in small boards of Norway spruce (Picea abies (L.) Karst.) exposed to tensile load in longitudinal direction. A sample with a central intergrown knot and one with an equivalent
loose knot were compared with reference samples made of clear wood with an artificial central circular or square hole, respectively.
The observed measurements were compared with a finite element (FE) simulation. The FE model was based on a geometric model
to quantify the local fibre orientation and a micromechanical model to estimate elastic constants of clear wood and knot tissue.
Both the measurements and simulation clearly illustrate a rather homogenous strain distribution around the intergrown knot.
In comparison, the natural optimisation of dispersing strain peaks is less efficient in the case of loose knots. The artificial
circular and square holes in samples with parallel fibre orientation lead to high gradients in the strain field and peak values
in vicinity of the disturbance. 相似文献
136.
Holger Zernetsch Alexandros Repanas Tim Rittinghaus Marc Mueller Irene Alfred Birgit Glasmacher 《Fibers and Polymers》2016,17(7):1025-1032
Tissue engineering is an interdisciplinary field which combines the basic principles of life sciences and engineering. One promising idea is the combination of scaffolds and living cells in order to produce new functional tissue. The scaffolds play the role of a microenvironment that guides the cells towards tissue formation and regeneration. One of the most frequently used techniques to produce scaffolds is electrospinning. Tissue engineered constructs have to exhibit physiological and mechanical properties comparable to the native tissue they are intended to replace. To create polymeric fibers with controlled orientation, a cylindrical collector that rotates at a certain speed could be used, creating fibers that run longitudinally. The process of gap-spinning enables the production of specifically aligned fibers. Aim of this study was to develop a novel setup capable of producing multilayered structures with controlled fiber angle. The structural, morphological and mechanical characteristics of the fibers were accessed using scanning electron microscopy and uniaxial tensile tests. Longer pre-stretching led to thinner (in the sub-micron scale), more brittle and less elastic fibers. In a nutshell, the results indicated that fiber mats of desired orientation, fiber diameter and mechanical properties could be produced by controlled gap-spinning with a translational collector. 相似文献
137.
138.
A soil science renaissance 总被引:1,自引:0,他引:1
The renaissance was an intellectually-rich period following a period of stasis in the medieval period. Something analogous appears to be currently taking place in soil science where novel approaches to thought are combined with a revival of ideas from the past. Renewed interest in agriculture (food, feed, fuel) and numerous publications have brought soils back onto the global research agenda. The need for up-to-date and fine resolution soil information and the revival of soil research has been highlighted and prioritised in several recent studies by the UN and other international organizations. Soil erosion, nutrient depletion and pollution are key issues that have been brought up in many recent reports - in most cases in relation to environmental degradation, climate change and world-food production. There is also an increased interest in soils in the popular press and media, and soils have entered the policy arena in many countries and several continents. We guestimate that about €3.2 billion is annually spent on soil research in Europe, North America, and some of the main countries in Asia and Oceania. For the global soil science community, there are challenges ahead to address the questions raised in these reports. There is a whole set of new techniques and methodologies in the wings waiting to take centre stage. There is a direct need to educate a new generation of soil scientists and to increase the influx of soil science students in many universities. The soil science community should benefit from the current upsurge in soil science, but the community has to deliver the goods and information that is wanted and much needed. 相似文献
139.
Severin Hohensinner Mathew Herrnegger Alfred P. Blaschke Christine Habereder Gertrud Haidvogl Thomas Hein Mathias Jungwirth Michael Weiβ 《CATENA》2008
River/floodplain restoration programs are often based on type-specific reference conditions of the respective river section. Most large rivers in the industrialized world are heavily degraded and lack near-natural reference sites. For that reason, historical analyses of the pre-channelization state have been used to define adequate restoration targets at the Austrian Danube section in the Alluvial Zone National Park downstream from Vienna. This study compares new reference data derived from 3D-reconstructions in the form of digital terrain models from two historical Danube river landscapes: the Machland floodplain in 1812 and the former floodplain in Vienna in 1849. The focus is on the original hydrological surface and subsurface connectivity of the river-floodplain systems related to different flow situations. Here, we use water cover, shorelines, depth of the groundwater table and inundation depth as surrogates for measuring connectivity. The results show that the two study sites naturally constituted extreme formations of the Austrian anabranching Danube sections. The Machland section was one of the narrowest floodplains but highly dynamic, and the Vienna/Lobau section was one of the broadest, whereby only the central part close to the main channel originally showed high morphological turnover. The analyses of hydrological surface connectivity relative to total floodplain extension reveal significant differences due to their basic geological and geographical conditions. Despite these basic differences, both study sites – in absolute numbers – showed similar extensions of the water bodies at low and mean flow. The depths of the groundwater table related to mean flow were also comparable. Prior to channelization, the groundwater conditions in both floodplains favored the formation of wet to moist alluvial forest communities. 相似文献
140.
Peter De Schryver Susana Seseña Bert Decaigny Tom Van de Wiele Willy Verstraete Nico Boon 《Journal of Cereal Science》2008
Syrup formation in refrigerated doughs is a problem since it reduces the doughs’ shelf life. Microbial exogenous xylanases associated with wheat kernels were found to play a role in this syruping phenomenon. Using xylanase-producing microorganisms isolated from wheat kernels, we investigated their potency to induce syruping in dough. Growth of the fungal xylanase producer Fusarium sp. (102 colony forming units (CFU)/g dough) and the bacterial xylanase producer Paenibacillus sp. (104 CFU/g dough) in synthetic media and their respective addition to wheat dough could not bring about a significant amount of syruping. However, when these species were grown on moist wheat kernels and an extract of these kernels containing both the organisms and its xylanases was made and added to dough, intensive syruping was noted. This effect was primarily attributed to the xylanases present in the extract. These findings suggest that the involvement of xylanase-producing microorganisms in the syruping phenomenon is situated prior to harvest. Additional quantitative analyses of microbial biomass present on wheat kernels revealed that the fungi in particular could be correlated to higher microbial exogenous xylanase activities on wheat. Our results indicate that the syruping is linked to fungal xylanase production on the wheat kernels in the field. 相似文献