6,008 research outputs found

    Bayesian networks as a decision support tool for rural water supply and sanitation sector

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    Despite the efforts made towards the Millennium Development Goals targets during the last decade, still millions of people across the world lack of improved access to water supply or basic sanitation. The increasing complexity of the context in which these services are delivered is not properly captured by the conventional approaches that pursue to assess water, sanitation and hygiene (WaSH) interventions. Instead, a holistic framework is required to integrate the wide range of aspects which are influencing sustainable and equitable provision of safe water and sanitation, especially to those in vulnerable situations. In this context, the WaSH Poverty Index (WaSH-PI) was adopted, as a multi-dimensional policy tool that tackles the links between access to basic services and the socio-economic drivers of poverty. Nevertheless, this approach does not fully describe the increasing interdependency of the reality. For this reason, appropriate Decision Support Systems (DSS) are required to i) inform about the results achieved in past and current interventions, and to ii) determine expected impacts of future initiatives, particularly taking into account envisaged investments to reach the targets set by the Sustainable Development Goals (SDGs). This would provide decision-makers with adequate information to define strategies and actions that are efficient, effective, and sustainable. This master thesis explores the use of object-oriented Bayesian networks (ooBn) as a powerful instrument to support project planning and monitoring, as well as targeting and prioritization. Based on WaSH-PI theoretical framework, a simple ooBn model has been developed and applied to reflect the main issues that determine access to safe water, sanitation and hygiene. A case study is presented in Kenya, where the Government launched in 2008 a national program aimed to increase the access to improved water, sanitation and hygiene in 22 of the 47 existing districts. Main impacts resulted from this initiative are assessed and compared against the initial situation. This research concludes that the proposed approach is able to accommodate the conditions at different scales, at the same time that reflects the complexities of WaSH-related issues. Additionally, this DSS represents an effective management tool to support decisionmakers to formulate informed choices between alternative actions

    Odon device: a promising tool to facilitate vaginal delivery and increase access to emergency care

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    The last innovation in operative vaginal delivery happened centuries ago with the invention of the forceps and the vacuum extractor. The World Health Organization Odon Device Research Group recently published a protocol for a feasibility and safety study for a new device (Odon device) which aims to revolutionize assisted vaginal delivery. This editorial discusses the device and its pathway to global use. Although preliminary results look promising, the rigorous three-phased WHO protocol needs completion before the device can be determined, based on the evidence, to be safe and effective.Fil: Belizan, Jose. Instituto de Efectividad Clínica y Sanitaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Harris Requejo, Jennifer. Johns Hopkins Bloomberg School of Public Health. Institute for International Programs; Estados Unido

    International trends in fresh avocado and avocado oil production and seasonal variation of fatty acids in New Zealand-grown cv. Hass : a thesis presented in partial fulfilment of the requirements for the degree of Master in Applied Science in Agribusiness at Massey University

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    Intensive cultivation of avocados for commercial purposes began in California and Florida and later in Israel, South Africa and Chile. Although a range of avocado cultivars are grown, Hass is the world's most widely-grown and exported cultivar. Avocado fruit has shown good commercial perspectives and planted areas show a tendency to increase. World production of avocado has grown on average 4.3% (over 760.000 MT) between 1988 and 1998. The main producers of avocado are Mexico (34%), USA (8%), Dominican Republic (7%), Indonesia (6%) Brazil (4%) and Israel (4%), Chile (2.4%), Spain (3%) and South Africa (2%) which during 1997 contributed together to 70% of the world production. Avocado world trade has increased greatly from 57,576 tonnes in 1980 to 238,306 tonnes in 1997. In 1997, the main players in the export market were Israel, Mexico, South Africa, USA and Chile. The main importers of this fruit were in Europe: Belgium, France, The Netherlands, Sweden, Switzerland, the United Kingdom, Germany, Spain, and in America: the USA and Canada and in Asia: Japan has emerged as a strong market since 1995. Average prices paid per metric ton have decreased over the years as higher volumes of fruit are traded and new exporters enter into the business. Avocado producer countries will face major challenges because of increasing production and low prices over the short and medium term. With the exception of Mexico, Israel and the U.S. the rest of the studied country producers are fairly new in the industry, thus, they possess great potential for growing. In New Zealand avocados are mainly cultivated in the North Island specifically in the Bay of Plenty and Northland areas. The New Zealand avocado Industry is based on the Hass cultivar. Avocado trees in New Zealand continue to be widely planted and with the entrance of new growers, in the future, the orchard area will continue to increase. The avocado industry in New Zealand is export driven. New Zealand's main export markets are Australia and recently the United States. Actual Australian market dominance by New Zealand would be reduced in the following 5 years due to a constant increase in Australian domestic avocado production. Since 1996, the U.S. has become an important market of destination for New Zealand avocados. Traditional supplier of the U.S. market has been Chile and it represents New Zealand's main competitor In avocado export leader countries usually the local market is supplied with fruit that does not meet export (usually strict) quality requirements. Great increases in production and export volumes are expected, therefore, it is forecast that large volumes of low price rated avocados would exist and would force the industry to look for alternative uses for avocados. Those avocados rejected during classification for export markets mainly due to defects in cosmetic appearance might be used for avocado oil extraction. The oil industry generally considered a by- product of the fresh fruit industry. For the multiplicity of applications and high prices that it achieves, avocado oil represents an interesting industry that should be further researched. Lipids are an important part of the composition of avocado fruit for a range of reasons. They contribute significantly to the taste of the fruit, and are used indirectly as a means of defining maturity since they correlate highly with dry matter. Although there has been some work carried out in New Zealand examining lipid changes and maturity, there has been no examination of the fatty acid makeup of the lipids, how they vary between regions, and what the lipid content is later in a commercial season. Such information is important from a fruit quality, health and marketing points of view. On seven occasions between September 1998 and April 1999, fruit from two orchards located in Te Puke and the Far North were harvested and analysed for dry matter, lipid content and fatty acid composition. Dry matter assessments were carried out using the commercial method and, the lipid fraction was extracted using a modification of the Bligh and Dyer technique. Later, the fatty acid analysis of the lipids was carried out by gas chromatography. Average dry matter increased over the period of study (September to April). Dry matter for Te Puke fruit increased from 24.6% to 36.4%, while dry matter from the Far North fruit increased from 24.1% to 32.3% over the same period of time. Total lipid content increased from 17.2% to 31.3% in Te Puke and from 16.4% to 26.7% in the Far North from September to April. The results imply that fruit from Te Puke could be preferred from the point of view of oil extraction because higher yields can be obtained than from fruit from the Far North. It was found a high and positive relationship exists between total lipids and dry matter content in avocados. During the study period, fruit from Te Puke showed consistently higher lipid content (and dry matter content) than fruit from the Far North. At both sites, the beneficial monounsaturated oleic acid was the major fatty acid synthesised, however, fruit from Te Puke showed higher levels of oleic acid than fruit from the Far North. From the nutrition point of view the ratio of monounsaturated (oleic and palmitoleic acid) to saturated fatty acids (palmitic acid) and the ratio of polyunsaturated (linoleic and linolenic acid) to saturated fatty acids found for the Far North and Te Puke regions compare favourably with those of the recommended olive oil. Due to similarities in lipid composition between olive oil and avocado oil, it can be implied that the high concentration of monounsaturated fatty acids in avocado will be beneficial to lower blood lipids as olive oil does. The food industry makes use of avocado oil to prepare concentrated foods, while the cosmetics industry prepares lotions and soaps for hair and skin treatments. Lastly, prestigious laboratories are also analysing the property of the flesh and oil for medical purposes. The information compiled here confirms that avocado oil compares to olive oil and can be regarded as a high- value product from the nutritional and the commercial point of view. On current production trends in New Zealand, the likelihood of an oil-extraction plant is not remote. An oil industry in New Zealand would benefit the growers because it will absorb the surplus of avocados in the local market that otherwise would compete with their first grade fruit

    Using financial futures in trading and risk management

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    The authors explain the features of an array of futures contracts and their basic pricing relationships and describe a few applications to show how investors and risk managers can use these contracts. Futures - and derivatives generally - allow economic agents to fine-tune the structure of their assets and liabilities to suit their risk preferences and market expectations. Futures are not a financing or investment vehicle per se, but a tool for transferring price risks associated with fluctuations in asset values. Some may use them to spread risk, others to take on risk. Financial futures (along with options) are best viewed as building blocks. Futures have facilitated the modern trend of separating conventional financial products into their basic components. They allow not only the reduction of transformation of investment risk but also the understanding and measurement of risk. The market for derivatives has grown enormously over the past decade. The value of exchange-traded eurodollar derivatives (futures and options) is equal to roughly 13 times the value of the underlying market. The volume of trading in financial futures now dwarfs the volume in traditional agricultural contracts. As emerging markets develop, given their inherently risky nature, expect financial futures to play a prominent role in risk management.Payment Systems&Infrastructure,Economic Theory&Research,International Terrorism&Counterterrorism,Banks&Banking Reform,Securities Markets Policy&Regulation,Commodities,Banks&Banking Reform,International Terrorism&Counterterrorism,Non Bank Financial Institutions,Economic Theory&Research

    Scarcity may promote cooperation in populations of simple agents

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    In the study of the evolution of cooperation, resource limitations are usually assumed just to provide a finite population size. Recently, however, it has been pointed out that resource limitation may also generate dynamical payoffs able to modify the original structure of the games. Here we study analytically a phase transition from a homogeneous population of defectors when resources are abundant to the survival of unconditional cooperators when resources reduce below a threshold. To this end, we introduce a model of simple agents, with no memory or ability of recognition, interacting in well-mixed populations. The result might shed light on the role played by resource constraints on the origin of multicellularity.Comment: 5 pages, 2 figure

    Beyond Arbitrage: "Good-Deal" Asset Price Bounds in Incomplete Markets

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    It is often useful to price assets and other random payoffs by reference to other observed prices rather than construct full-fledged economic asset pricing models. This approach breaks down if one cannot find a perfect replicating portfolio. We impose weak economic restrictions to derive usefully tight bounds on asset prices in this situation. The bounds basically rule out high Sharpe ratios - `good deals' - as well as arbitrage opportunities. We present the method of calculation, we extend it to a multiperiod context by finding a recursive solution, and we apply it to option pricing examples including the Black-Scholes setup with infrequent trading, and a model with stochastic stock volatility and a varying riskfree rate.

    Analytical models for well-mixed populations of cooperators and defectors under limiting resources

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    In the study of the evolution of cooperation, resource limitations are usually assumed just to provide a finite population size. Recently, however, agent-based models have pointed out that resource limitation may modify the original structure of the interactions and allow for the survival of unconditional cooperators in well-mixed populations. Here, we present analytical simplified versions of two types of agent-based models recently published: one in which the limiting resource constrains the ability of reproduction of individuals but not their survival, and a second one where the limiting resource is necessary for both reproduction and survival. One finds that the analytical models display, with a few differences, the same qualitative behavior of the more complex agent-based models. In addition, the analytical models allow us to expand the study and identify the dimensionless parameters governing the final fate of the system, such as coexistence of cooperators and defectors, or dominance of defectors or of cooperators. We provide a detailed analysis of the occurring phase transitions as these parameters are varied.Comment: 7 pages, 8 figure

    El fuste de la democracia liberal sigue siendo demasiado recto

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    This article analyzes the difficulties that liberal democracies face in accommodating a diversity of values, interests and identities in contexts of national pluralism (plurinational states). The first section analyzes the fallacy of abstraction and the distortions of the concept of pluralism that occur in enlightenment-based theories. The second section begins with a brief description of three classic institutional solutions for accommodating plurinational societies in liberal democracies: federalism, consociationalism and secession. A comparative analysis of nineteen decentralized federal or regional democracies is then discussed in order to evaluate the adequacy of federalism in regulating political recognition and accommodation in contexts of national pluralism. My conclusion suggests that these two objectives can only be achieved by means of plurinational federalism or partnership, which may also include consociational processes that regulate the possible secession of minority nations.Este artículo analiza las dificultades de las democracias liberales en el momento de acomodar la diversidad de valores, intereses e identidades en contextos de pluralismo nacional (estados plurinacionales). en la primera sección, se analizan dos distorsiones presentes en la tradición liberal: la falacia de la abstracción y el modo de tratar el pluralismo en las teorías que arrancan de la Ilustración. en la segunda sección, se mencionan las tres soluciones institucionales clásicas para acomodar sociedades plurinacionales en las democracias liberales: federalismo, consociacionalismo y secesión. A continuación, se examina la adecuación del federalismo para regular el reconocimiento y la acomodación política del pluralismo nacional a partir de un análisis comparado de diecinueve democracias federales o regionales descentralizadas. La conclusión es que el reconocimiento y la acomodación sólo pueden alcanzarse a través de los modelos de federalismo plurinacional o de partenariado (en combinación, o no, con instituciones y procesos consociacionales que regulen la posible secesión de las naciones minoritarias)

    Bastida cap a la simbolització. Reflexions a partir dels ponts d’en Kim

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    Amb aquest article la meva intenció és plantejar algunes reflexions sobre la tècnica en el treball terapèutic amb nensamb un funcionament psíquic primitiu. Posaré el focus d’atenció en la necessitat d’adaptar la forma d’intervenció enfunció del nivell d’estructuració psíquica en què s’expressa elnen en cada moment de la sessió. Quan el nivell d’organització psíquica que es manifesta és simbòlic, podrem treballar ambeines tan complexes com la interpretació en qualsevol de les seves variants. Però quan els nostres pacients funcionen ennivells més arcaics, previs al simbolisme, haurem de trobar altres recursos perquè la nostra intervenció sigui efectivament nutritiva. En molts casos, serà necessari treballar en nivells encara presents d’indiferenciació per dotar d’una sustentacióque tal vegada mai no s’ha viscut prou. Tot això, tractaré deposar-ho en relació amb la meva experiència de treball amb enKim, a partir de la qual van sorgir les preguntes que aquí intento aclarir
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