963 resultados para Current Canadian Policies
Resumo:
Breast sarcomas are rare neoplasms of the breast that need to be clearly distinguished from the very common breast carcinomas and treated in a multidisciplinary manner modelled after treatment paradigms in other sarcoma locations. An increasing need to differentiate sarcoma sub-types based on molecular characteristics that will also be depicted in differential treatment sensitivities and development of specifically targeted therapies are equally valid in sarcomas in general and in breast sarcomas in particular. Of special interest in breast are sarcomas developing after breast irradiation for a previous breast carcinoma, a scenario that is increasingly common, given the increasing trends of breast conservation in the surgical treatment of breast carcinoma that necessitates the adjuvant use of radiotherapy.
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Coffee and cocoa represent the main sources of income for small farmers in the Northern Amazon Region of Ecuador. The provinces of Orellana and Sucumbios, as border areas, have benefited from investments made by many public and private institutions. Many of the projects carried out in the area have been aimed at energising the production of coffee and cocoa, strengthening the producers’ associations and providing commercialisation infrastructure. Improving the quality of life of this population threatened by poverty and high migration flows mainly from Colombia is a significant challenge. This paper presents research highlighting the importance of associative commercialisation to raising income from coffee and cocoa. The research draws on primary information obtained during field work, and from official information from the Ministry of Agriculture. The study presents an overview of current organisational structures, initiatives of associative commercialisation, stockpiling of infrastructure and ownership regimes, as well as estimates for both ‘robusta’ coffee and national cocoa production and income. The analysis of the main constraints presents different alternatives for the implementation of public land policies. These policies are aimed at mitigating the problems associated with the organisational structure of the producers, with processes of commercialisation and with environmental aspects, among others.
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Since the mid 90's, international actors as well as governmental actors have raised their interest into the development of irrigation's potential that is still largely unexploited in Niger. It seems all the more interesting as it could answer the needs of a fast growing population (3.3% per year). However, if everyone agrees on the need to development this system, the current implementation triggers questions on the process itself and its side effects. National and international policies on this matter were build upon an historical process through colonial, post-colonial and then the late 1980's neoliberal structures, leading to a business model that reveals a discrepancy between the state logic and the farming one. This business model asks for a high capacity of mobilization of resources unachievable for many, especially when they want to address small-scale irrigation (area
Resumo:
The classical approach to predicting the geographical extent of species invasions consists of training models in the native range and projecting them in distinct, potentially invasible areas. However, recent studies have demonstrated that this approach could be hampered by a change of the realized climatic niche, allowing invasive species to spread into habitats in the invaded ranges that are climatically distinct from those occupied in the native range. We propose an alternative approach that involves fitting models with pooled data from all ranges. We show that this pooled approach improves prediction of the extent of invasion of spotted knapweed (Centaurea maculosa) in North America on models based solely on the European native range. Furthermore, it performs equally well on models based on the invaded range, while ensuring the inclusion of areas with similar climate to the European niche, where the species is likely to spread further. We then compare projections from these models for 2080 under a severe climate warming scenario. Projections from the pooled models show fewer areas of intermediate climatic suitability than projections from the native or invaded range models, suggesting a better consensus among modelling techniques and reduced uncertainty.
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Rat superior cervical ganglion (SCG) neurons express low-threshold noninactivating M-type potassium channels (I-K(M)), which can be inhibited by activation of M-1 muscarinic receptors (M-1 mAChR) and bradykinin (BK) B-2 receptors. Inhibition by the M1 mAChR agonist oxotremorine methiodide (Oxo-M) is mediated, at least in part, by the pertussis toxin-insensitive G-protein G alpha (q) (Caulfield et al., 1994; Haley et al., 1998a), whereas BK inhibition involves G alpha (q) and/or G alpha (11) (Jones et al., 1995). G alpha (q) and G alpha (11) can stimulate phospholipase C-beta (PLC-beta), raising the possibility that PLC is involved in I-K(M) inhibition by Oxo-M and BK. RT-PCR and antibody staining confirmed the presence of PLC-beta1, - beta2, - beta3, and - beta4 in rat SCG. We have tested the role of two PLC isoforms (PLC-beta1 and PLC-beta4) using antisense-expression constructs. Antisense constructs, consisting of the cytomegalovirus promoter driving antisense cRNA corresponding to the 3'-untranslated regions of PLC-beta1 and PLC-beta4, were injected into the nucleus of dissociated SCG neurons. Injected cells showed reduced antibody staining for the relevant PLC-beta isoform when compared to uninjected cells 48 hr later. BK inhibition of I-K(M) was significantly reduced 48 hr after injection of the PLC-beta4, but not the PLC-beta1, antisense-encoding plasmid. Neither PLC-beta antisense altered M-1 mAChR inhibition by Oxo-M. These data support the conclusion of Cruzblanca et al. (1998) that BK, but not M-1 mAChR, inhibition of I-K(M) involves PLC and extends this finding by indicating that PLC-beta4 is involved.
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The literature shows that obesity is a public health problem concerning especially the general paediatrician. While prevention has probably more chances of success than treatment, drugs or, in case of failure, the surgical approach are reserved for extreme cases. In the domain of infectiology the different laboratory tests allow only partially to diagnose severe infections. But in the context of a potential influenza pandemic rapid virologic tests become more and more important. They allow a more precise diagnosis and a reduction of hospitalisations and of antibiotic prescriptions. A review of the north American experience with the pneumococal vaccine shows that the heptavalent vaccine will change our approach in infants with fever in whom we suspect a severe infection.
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A detailed investigation has been conducted on core samples taken from 17 portland cement concrete pavements located in Iowa. The goal of the investigation was to help to clarify the root cause of the premature deterioration problem that has become evident since the early 1990s. Laboratory experiments were also conducted to evaluate how cement composition, mixing time, and admixtures could have influenced the occurrence of premature deterioration. The cements used in this study were selected in an attempt to cover the main compositional parameters pertinent to the construction industry in Iowa. The hardened air content determinations conducted during this study indicated that the pavements that exhibited premature deterioration often contained poor to marginal entrained-air void systems. In addition, petrographic studies indicated that sometimes the entrained-air void system had been marginal after mixing and placement of the pavement slab, while in other instances a marginal to adequate entrained-air void system had been filled with ettringite. The filling was most probably accelerated because of shrinkage cracking at the surface of the concrete pavements. The results of this study suggest that the durability—more sciecifically, the frost resistance—of the concrete pavements should be less than anticipated during the design stage of the pavements. Construction practices played a significant role in the premature deterioration problem. The pavements that exhibited premature distress also exhibited features that suggested poor mixing and poor control of aggregate grading. Segregation was very common in the cores extracted from the pavements that exhibited premature distress. This suggests that the vibrators on the paver were used to overcome a workability problem. Entrained-air voids formed in concrete mixtures experiencing these types of problems normally tend to be extremely coarse, and hence they can easily be lost during the paving process. This tends to leave the pavement with a low air content and a poor distribution of air voids. All of these features were consistent with a premature stiffening problem that drastically influenced the ability of the contractor to place the concrete mixture. Laboratory studies conducted during this project indicated that most premature stiffening problems can be directly attributed to the portland cement used on the project. The admixtures (class C fly ash and water reducer) tended to have only a minor influence on the premature stiffening problem when they were used at the dosage rates described in this study.
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The value of providing paved shoulders adjacent to many higher volume roadways has been accepted in many states across the country. Iowa’s paved shoulder policy is considerably more conservative than neighboring states, particularly on rural four-lane and high-volume two-lane highways. The objectives of this research are to examine current design criteria for shoulders employed in Iowa and surrounding states, compare benefits and costs of alternative surface types and widths, and make recommendations based on this analysis for consideration in future design policies for primary highway in Iowa. The report finds that many safety and maintenance benefits would result from enhancing Iowa’s paved shoulder and rumble strip design practices for freeways, expressways, and Super 2 highway corridors. The benefits of paved shoulders include reduced numbers of certain crashes, higher capacity potentials, reduced maintenance, enhanced opportunities for other users such as bicyclists, and even possible increased longevity of pavements. Alternative paved shoulder policies and programming strategies are also offered, with detailed assessments of the benefits, costs, and budget impacts.
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The Agricultural Risk Protection Act greatly increased the expected marginal net benefit of farmers buying high-coverage crop insurance policies by coupling premium subsidies to coverage level. This policy change, combined with cross-sectional variations in expected marginal net benefits of high-coverage policies, is used to estimate the role that premium subsidies play in farmers’ crop insurance decisions. We use county data for corn, soybeans, and wheat to estimate regression equations that are then used to obtain insight into two policy scenarios. We first estimate that eventual adoption of actuarially fair incremental premiums, combined with current coupled subsidies, would increase farmers’ purchase of high-coverage policies by almost 400 percent from 1998 levels across the three crops and two plans of insurance included in the analysis. We then estimate that a return to decoupled subsidies would decrease farmers’ high-coverage purchase decisions by an average of 36 percent.
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This paper formulates power allocation policies that maximize the region of mutual informationsachievable in multiuser downlink OFDM channels. Arbitrary partitioning ofthe available tones among users and arbitrary modulation formats, possibly different forevery user, are considered. Two distinct policies are derived, respectively for slow fadingchannels tracked instantaneously by the transmitter and for fast fading channels knownonly statistically thereby. With instantaneous channel tracking, the solution adopts theform of a multiuser mercury/waterfilling procedure that generalizes the single-user mercury/waterfilling introduced in [1, 2]. With only statistical channel information, in contrast,the mercury/waterfilling interpretation is lost. For both policies, a number of limitingregimes are explored and illustrative examples are provided.
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Although Iowa has some of the most productive agricultural land in the nation, it also maintains a very extensive road network.Consequently, landowners and roadway officials often must deal with drainage issues affecting private lands and public highways. However, many individuals are unfamiliar with legal drainage requirements, practices, and procedures, which can result in misunderstandings concerning maintenance responsibilities for drainage facilities, sometimes leading to litigation. To assist propertyowners, public agencies, and others with interest in better understanding drainage maintenance responsibilities, a reference manual was developed to describe Iowa’s drainage laws and offer interpretations in a clear and concise manner. To develop a comprehensive drainage manual, researchers identified and reviewed current available literature. These resources described pertinent drainage issues and presented explanations of legal responsibilities. The literature review included manuals and guides from Iowa, surrounding states, and federal agencies. Researchers developed a survey to assess the needs and interestsof potential users of an Iowa drainage law manual. Survey responses were used to identify common problems and concerns among individuals who encounter drainage issues on a regular basis. Issues mentioned in the survey responses included interpretation of drainage laws and commonly encountered questions relating to public improvements and private interests. Many individuals, including county engineers, stated interest in specific topics such as maintenance and/or diversion of drainage, landowner issues, and upstream and downstream impacts. Overall, the survey provided researchers with valuable information regarding drainage issues, problems, current policies, and concerns. A comprehensive manual of Iowa drainage law will assist agencies and individuals in interpreting current code requirements and in implementing effective and beneficial solutions when dealing with drainage issues.
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We investigate the problem of finding minimum-distortion policies for streaming delay-sensitive but distortion-tolerant data. We consider cross-layer approaches which exploit the coupling between presentation and transport layers. We make the natural assumption that the distortion function is convex and decreasing. We focus on a single source-destination pair and analytically find the optimum transmission policy when the transmission is done over an error-free channel. This optimum policy turns out to be independent of the exact form of the convex and decreasing distortion function. Then, for a packet-erasure channel, we analytically find the optimum open-loop transmission policy, which is also independent of the form of the convex distortion function. We then find computationally efficient closed-loop heuristic policies and show, through numerical evaluation, that they outperform the open-loop policy and have near optimal performance.
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We analyze the impact of trade liberalization, removal of production subsidies, and elimination of consumption distortions in world sugar markets using a partial-equilibrium international sugar model calibrated on 2002 market data and current policies. The removal of trade distortions alone induces a 27% price increase while the removal of all trade and production distortions induces a 48% increase by 2011/12 relative to the baseline. Aggregate trade expands moderately, but location of production and trade patterns change substantially. Protectionist OECD countries (the EU, Japan, the US) experience an import expansion or export reduction and significant contraction in production in unfettered markets. Competitive producers in both OECD countries (Australia) and non-OECD countries (Brazil, Cuba), and even some protected producers (Indonesia, Turkey), expand production when all distortions are removed. Consumption distortions have marginal impacts on world markets and location of production. We discuss the significance of these results in the context of mounting pressures to increase market access in highly protected OECD countries and the impact on non-OECD countries.
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The ways in which the dominant cultural majority frames the educationalsystem determine perceptions of its own identity and understandings ofthe ‘other.’ In this article I take a political approach, by examining themanagement of cultural diversity within Spanish education policies, treating“education as the mirror of society”. This article analyzes Spanish challengesand policies approaches towards the management of immigrationrelated diversity in education. The main finding is that there is not one approach,but several, due to both the decentralized character of the educationsystem and the multiplicity of diversity that is at stake (i.e. language,religion, culture etc.)
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Arenaviruses are a large group of emerging viruses including several causative agents of severe hemorrhagic fevers with high mortality in man. Considering the number of people affected and the currently limited therapeutic options, novel efficacious therapeutics against arenaviruses are urgently needed. Over the past decade, significant advances in knowledge about the basic virology of arenaviruses have been accompanied by the development of novel therapeutics targeting different steps of the arenaviral life cycle. High-throughput, small-molecule screens identified potent and broadly active inhibitors of arenavirus entry that were instrumental for the dissection of unique features of arenavirus fusion. Novel inhibitors of arenavirus replication have been successfully tested in animal models and hold promise for application in humans. Late in the arenavirus life cycle, the proteolytic processing of the arenavirus envelope glycoprotein precursor and cellular factors critically involved virion assembly and budding provide further promising 'druggable' targets for novel therapeutics to combat human arenavirus infection.