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Agricultural, food, and water nanotechnologies for the poor | Opportunities, constraints, and role of the Consultative Group on International Agricultural Research
2015
Gruère, Guillaume P.; Narrod, Clare A.; Abbott, Linda
EPTD; MTID | Discussion paper | GRP40; IFPRI1 | Non-PR | There are a number of potential opportunities associated with agricultural, food, and water nanotechnology for the poor, but to achieve such opportunities a number of challenges need to be overcome. This paper first provides a rapid assessment of key technologies that could have a large impact on the poor via increased agricultural productivity, improved food and water safety, and nutrition. Second, it reviews some of the main challenges to their deployment and adoption by the poor. It concludes with a discussion of the potential role of the CGIAR in facilitating the poor’s access to beneficial nanotechnologies.
Показать больше [+] Меньше [-]Absolute quantification of norovirus capsid protein in food, water, and soil using synthetic peptides with electrospray and MALDI mass spectrometry Полный текст
2015
Hartmann, Erica M. | Colquhoun, David R. | Schwab, Kellogg J. | Halden, Rolf U.
Norovirus infections are one of the most prominent public health problems of microbial origin in the U.S. and other industrialized countries. Surveillance is necessary to prevent secondary infection, confirm successful cleanup after outbreaks, and track the causative agent. Quantitative mass spectrometry, based on absolute quantitation with stable-isotope labeled peptides, is a promising tool for norovirus monitoring because of its speed, sensitivity, and robustness in the face of environmental inhibitors. In the current study, we present two new methods for the detection of the norovirus genogroup I capsid protein using electrospray and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The peptide TLDPIEVPLEDVR was used to quantify norovirus-like particles down to 500 attomoles with electrospray and 100 attomoles with MALDI. With MALDI, we also demonstrate a detection limit of 1 femtomole and a quantitative dynamic range of 5 orders of magnitude in the presence of an environmental matrix effect. Due to the rapid processing time and applicability to a wide range of environmental sample types (bacterial lysate, produce, milk, soil, and groundwater), mass spectrometry-based absolute quantitation has a strong potential for use in public health and environmental sciences.
Показать больше [+] Меньше [-]Reconciling food and water security objectives of MENA and sub-Saharan Africa: is there a role for large-scale agricultural investments? Полный текст
2015
Williams, Timothy O.
The attainment of food and water security rank high on the agendas of governments in the Middle East and North Africa (MENA) region and sub-Saharan Africa (SSA). Although the objectives are similar, the underlying drivers, resource endowments and opportunities for achieving them are different. Differences between two regions in natural resource endowment and investment capital stock can, in theory, lead to mutually beneficial trade to achieve desired objectives. Concerns about the recent food crises coupled with the disparity in land and water endowment and investable capital between MENA and SSA have led in recent years to investment in agricultural land in the latter by a number of MENA countries with the aim of producing food. At the same time, many SSA countries seek these investments to infuse capital, technology and know-how into their agricultural sector to improve productivity, food security and rural livelihoods. However, these recent foreign direct agricultural investments have to date performed poorly or have been abandoned without achieving the initial objectives of setting them up. Based on research conducted in selected sub-Saharan countries, this paper analyses the reasons for the failure of these investments. It then reviews a few successful agricultural investments by private sector companies with a long history of operation in SSA. Juxtaposing lessons distilled from failed and successful case studies, the paper argues that large-scale agricultural investments that take advantage of this accumulated knowledge are needed and do have a critical role to play. Such investments, when they also incorporate ecosystems management practices and smallholder inclusive business models in their operations, can serve as appropriate instruments to reconcile the food and water security objectives of both the MENA region and SSA, while promoting sustainable intensification of agriculture and improved rural livelihoods in SSA.
Показать больше [+] Меньше [-]Chinese State-Owned Enterprise Investment in Mekong Hydropower: Political and Economic Drivers and Their Implications across the Water, Energy, Food Nexus Полный текст
2015
Nathanial Matthews | Stew Motta
Over the last decade, Chinese State-Owned Enterprises have emerged as among the most active investors in Mekong Basin hydropower development. This paper uses a political economy analysis to examine the forces that drive Chinese State-Owned Enterprises to invest in hydropower in the Mekong Basin. We focus our analysis on the Lancang (Upper Mekong River) in China and in the Greater Mekong Subregion (GMS), with an emphasis on Cambodia. The analysis reveals how powerful political and economic forces from within China and the GMS influence the pace, location and scale of investments in hydropower. These forces include foreign exchange reserves, trade packages and foreign direct investment, and political alliances. Combining the political economy and nexus approaches, we conclude that although policies from China recognize interconnections across the nexus, political and economic forces craft narratives that downplay or disregard these nexus interconnections and trade-offs. This in turn, influences how trade-offs and interconnections in hydropower development are managed and recognized in both local and transboundary contexts, thereby, creating potentially significant negative impacts on livelihoods, food security and the environment.
Показать больше [+] Меньше [-]A Step towards developing strategies for optimal allocation of irrigation water for food security : Farmers’ conceptions on key issues in Ethiopia Полный текст
2015
Christersson, Jenni | Helsingin yliopisto, Maatalous-metsätieteellinen tiedekunta, Maataloustieteiden laitos | University of Helsinki, Faculty of Agriculture and Forestry, Department of Agricultural Sciences | Helsingfors universitet, Agrikultur- och forstvetenskapliga fakulteten, Institutionen för lantsbruksvetenskaper
This case study sheds new light on rural water use and related social, aconomic and environmental dimensions and proposes government intervention in order to ensure water rights and protect public value of fairness. The aim is to highlight farmers’ perspectives on irrigation water use and related obstacles, and specifically distinguish if views are connected to farmers’ underlying socioeconomic or agro-ecologic factors. For further considerations adaptive capacity of community for irrigation water fees is explored. The research material consists of semi-structured interviews for farmers (n=63), government organizations (n=3) and agricultural enterprises (n=2). Economic groups were formed via analysis of asset-based economic status. Grouping based on agricultural water use was conducted through categorization. Costs and lack of knowledge were identified as the main barriers for adopting advanced irrigation technology. The study showed prevailing allocation system is in need of reformation. When designing rural policy, farmers’ perceptions should be respected. Water allocation is considered unfair community-wide and social conflicts are largely faced. Those who do not suffer from conflicts are most commonly rich. Technology transfer offer potential benefits, but community needs to be mobilized. Grouping based on irrigation water usage may be used for targeting policies. Economic grouping may be used for distinguishing farmers’ behavior when designing change in economic conditions or conflict resolution strategy. The complementary role of this study is to bring out special focus on development for institutional capacity-building; strengthening the forcing nature of laws and user rights. This may reduce the attractiveness for corruption in the process. Under these conditions, the greatest benefits may be obtained by giving top priority instead of irrigation improvement, but conflict mediation and establishment of water markets.
Показать больше [+] Меньше [-]Evaluation of different buffered peptone water (BPW) based enrichment broths for detection of Gram-negative foodborne pathogens from various food matrices Полный текст
2015
Margot, H. | Zwietering, M.H. | Joosten, H. | O'Mahony, Emer | Stephan, R.
This study evaluated the effects of changing the composition of the pre-enrichment medium buffered peptone water (BPW) on the growth of stressed and unstressed Gram-negative foodborne pathogens in a one-broth enrichment strategy. BPW supplemented with an available iron source and sodium pyruvate, along with low levels of 8-hydroxyquinoline and sodium deoxycholate (BPW-S) improved the recovery of desiccated Cronobacter spp. from powdered infant formula. Growth of Salmonella and STEC was comparable in all BPW variants tested for different food matrices. In products with high levels of Gram-negative background flora (e.g. sprouts), the target organisms could not be reliably detected by PCR in any of the BPW variants tested unless the initial level exceeded 103cfu/10g of sprouts.Based on these results we suggest BPW-S for a one-broth enrichment strategy of stressed Gram-negative foodborne pathogens from dry products. However, a one-broth enrichment strategy based on BPW variants tested in this evaluation is not recommended for produce with a high level of Gram-negative background flora due to very high detection limits.
Показать больше [+] Меньше [-]دور الزراعة المائية في تحقيق الأمن المائي والغذائي في فلسطين | Role of Hydroponics in Attaining Water and Food Security in Palestine Полный текст
2015
غالب طالب بدر بدر | Ghaleb Taleb Bader Bader | عبد الرحمن التميمي | عبد الوهاب الصباغ | مروان غانم
Chinese State-Owned Enterprise Investment in Mekong Hydropower: Political and Economic Drivers and Their Implications across the Water, Energy, Food Nexus Полный текст
2015
Matthews, Nathanial | Motta, Stew
Over the last decade, Chinese State-Owned Enterprises have emerged as among the most active investors in Mekong Basin hydropower development. This paper uses a political economy analysis to examine the forces that drive Chinese State-Owned Enterprises to invest in hydropower in the Mekong Basin. We focus our analysis on the Lancang (Upper Mekong River) in China and in the Greater Mekong Subregion (GMS), with an emphasis on Cambodia. The analysis reveals how powerful political and economic forces from within China and the GMS influence the pace, location and scale of investments in hydropower. These forces include foreign exchange reserves, trade packages and foreign direct investment, and political alliances. Combining the political economy and nexus approaches, we conclude that although policies from China recognize interconnections across the nexus, political and economic forces craft narratives that downplay or disregard these nexus interconnections and trade-offs. This in turn, influences how trade-offs and interconnections in hydropower development are managed and recognized in both local and transboundary contexts, thereby, creating potentially significant negative impacts on livelihoods, food security and the environment.
Показать больше [+] Меньше [-]Application of modified magnetic nanoparticles as a sorbent for preconcentration and determination of nickel ions in food and environmental water samples Полный текст
2015
Mirabi, Ali | Shokuhi Rad, Ali | Nourani, Samaneh
A new solid-phase extraction sorbent was used for the separation/preconcentration of Ni(II) ions prior to their determination by flame atomic absorption spectrometry. It was prepared by immobilization of dithiooxamide on magnetic nanoparticles (MNPs) of magnetite (Fe3O4) coated with cationic surfactant sodium dodecyl sulfate. The properties of sorbent and MNPs were characterized by scanning electron microscope and transmission electron microscope. Some parameters affecting extraction, such as pH, adsorbent dosage, and eluent concentration and volume) were optimized. The calibration graph was linear in the range 30–5000 µg.L⁻¹ with a limit of determination of 3.9 µg.L⁻¹. The relative standard deviation for Ni ions was 1.3%. The method was applied to the determination of trace amounts of Ni(II) ions in water and food samples.
Показать больше [+] Меньше [-]Selective Solid-Phase Extraction and Trace Monitoring of Lead Ions in Food and Water Samples Using New Lead-Imprinted Polymer Nanoparticles Полный текст
2015
Behbahani, Mohammad | Hassanlou, Parmoon Ghareh | Amini, Mostafa M. | Moazami, Hamid Reza | Abandansari, Hamid Sadeghi | Bagheri, Akbar | Zadeh, Salman Hassan
A solid-phase extraction method using Pb²⁺ion-imprinted polymer (Pb²⁺-IIP) nanoparticles combined with flame atomic absorption spectrophotometry (FAAS) was developed for the preconcentration and trace monitoring of lead ions in environmental samples. The Pb²⁺-IIP nanoparticles were obtained by precipitation polymerization of 4-vinylpyridine (the functional monomer), ethylene glycol dimethacrylate (the cross-linker), 2,2′-azobisisobutyronitrile (the initiator), 4-(2-pyridylazo) resorcinol (the lead-binding ligand), and lead ions (the template ion) in acetonitrile solution. The Pb²⁺-IIP nanoparticles were characterized by Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric and differential thermal analysis (TGA/DTA), and by scanning electron microscopy (SEM). Different affecting parameters on the adsorption and desorption of this solid-phase extraction process were evaluated and optimized. Under the optimized conditions, the detection limit for the proposed method was found to be 0.9 μg L⁻¹, while the relative standard deviation (RSD) for five replicate measurements was calculated to be <4 %. For proving that the proposed method is reliable, a range of food and water samples with different and complex matrices was used.
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