14,112 research outputs found


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    Community/Rural/Urban Development,


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    A characteristic of our rural policies is that we seem to treat farm policy and other rural policy as if agriculture and the rest of the rural economy and society are separate. Literature from each perspective tends to ignore the existence and context of the other. There has been enough change in the rural context, however, to require a different approach to rural policy analysis and formulation. We must start from a comprehensive view of the rural economy, including both the agricultural and nonagricultural rural economies. The paper discusses issues that have changed the rural policy context: the changed rural economic structure, macro forces, farm-nonfarm interdependence, and the political arena. These changing contexts create new opportunities for rural policy formulation. The paper concludes by suggesting that agricultural economists will contribute more to systematic knowledge and policy formulation if they base analysis on the changed objective conditions in rural areas, and utilize more theoretically-based analysis.Community/Rural/Urban Development,

    The Use of an Anthrone Reagent to Detect Sugar Meals and Their Persistence in the Mosquito \u3ci\u3eAedes Triseriatus\u3c/i\u3e (Diptera: Culicidae)

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    Adults of Aedes triseriatus were fed water, blood, and 10% pure and mixed solutions of glucose, fructose and sucrose. Adults were tested for fructose by the cold-anthrone test 0, 1, 4, 12, and 24 h after feeding. Water-fed males and females and blood-fed females were anthrone negative. Glucose-fed males were anthrone negative but some glucose-fed females were weakly anthrone positive immediately after feeding. Many adults fed a mixture of glucose, fructose and sucrose were anthrone negative 12 h after feeding and all were anthrone negative after 24 h. The interpretation of negatives in the anthrone test is discussed with respect to the dynamics of nectar feeding, metabolic rates and sampling regimes

    Swarming and Mating in \u3ci\u3eAedes Provocans\u3c/i\u3e (Diptera: Culicidae)

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    Male Aedes provocans formed canopy-level linear swarms in association with prominent trees along hedgerows or convex prominences along woodlot margins. Males oriented along the east-west or north-south axis of the swarm site and flew continuously in alternating directions along the longitudinal axis of the swarm. Swarming began shortly before (mean=-0.78 crep) and ended after sunset (mean=0.81 crep). The time of onset of swarming was more variable than the time of cessation; on 3 of 5 occasions, swarming stopped abruptly at 0.94 crep, about 2 minutes before the end of civil twilight. Swarming began 4 d after the onset of emergence of the adults and persisted for 3 weeks, but copulations were observed for only the first 6 d. In-flight mating always took place after sunset, many minutes after the onset of swarming. On average, copulation lasted 9.9 s

    The Age Structure of a Population of \u3ci\u3eAedes Provocans\u3c/i\u3e (Diptera: Culicidae) in Southwestern Ontario

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    In a previous paper it was shown that an eastern-Ontario population of the early-spring mosquito Aedes provocans had an atypical age structure: the adult-female population aged rapidly and synchronously, achieving an advanced gonotrophic age in an unusually brief period of time. The present study examined the age structure of Ae. provocans near Waterloo, in south-western Ontario, at a site at which adult emergence occurred over a wider, more variable period and at which the preferred nectar sources for young adults were much less abundant. In Waterloo, the adult-female population aged more slowly and much less synchronously than in eastern Ontario. The role of resources, particularly nectar, in leading to delayed aging, is discussed

    The Gonotrophic-Age Structure of a Population of the \u3ci\u3eSimulium Venustum\u3c/i\u3e Complex (Diptera: Simuliidae) in Algonquin Park, Ontario

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    Eight techniques for the determination of parity and gonotrophic age were assessed for the obligatorily anautogenous blackfly-species complex, Simulium venustum Say. All females could be age-graded by the presence or absence of dilatations on the ovarioles. However, multiple dilatations on a single ovariole were not found and the Polovodova method could not be used to determine the number of completed gonotrophic cycles. Most females could be age-graded by the appearance of the Malpighian tubules, which undergo morphological changes, probably as a result of a bloodmeal. In some cases, the size of the fat body, the presence of retained (relict), mature ova and the presence of meconium in the gut could be used as accessory age-grading criteria. Insemination status, the volume of the esophageal diverticulum, and the stage of development of the terminal ovarian follicles could not be used to age-grade females. The literature of age-grading in blackflies is reviewed, with special reference to the interpretability of the Polovodova method. Seasonal changes in the gonotrophic-age structure of a population of the S. venustum complex in Algonquin Park, ON, Canada, were examined over two years. The maximal proportion of parous females in the population was 75 and 62% in the two years, respectively. There was weak evidence that parous females were more likely to host seek in the morning and nulliparous females in the afternoon. Parity declined in mid-season, due to the recruitment of newly emerged adults to the population


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    Applying indexes of economic instability and industrial diversification to Idaho's forty-three nonmetropolitan counties, this paper tests the hypothesis that unemployment is more stable in a more diverse economy. While results support the hypothesis, other aspects of a county's economic structure are just as influential. Indiscriminate diversification will not necessarily bring economic stability.Community/Rural/Urban Development,


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    This study's objective is to identify and understand the factors important to hardwood processors' location decisions in the northern and central Appalachian region. Concepts from neoclassical and behavioral location theories were integrated to develop a general framework for analyzing these decisions. Logit regression analysis was used to determine those establishment characteristics related to the likelihood of location search. To a great extent, establishments locate based on personal ties and do not conduct searches. Most variables found to influence the likelihood of search are not controllable by state or local governments. The implications are that existing establishments should be targeted for retention and expansion, rather than focusing on recruitment.Community/Rural/Urban Development, Industrial Organization,

    A Dose of Reality: Overcoming Usability Challenges in VR Head-Mounted Displays

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    We identify usability challenges facing consumers adopting Virtual Reality (VR) head-mounted displays (HMDs) in a survey of 108 VR HMD users. Users reported significant issues in interacting with, and being aware of their real-world context when using a HMD. Building upon existing work on blending real and virtual environments, we performed three design studies to address these usability concerns. In a typing study, we show that augmenting VR with a view of reality significantly corrected the performance impairment of typing in VR. We then investigated how much reality should be incorporated and when, so as to preserve users’ sense of presence in VR. For interaction with objects and peripherals, we found that selectively presenting reality as users engaged with it was optimal in terms of performance and users’ sense of presence. Finally, we investigated how this selective, engagement-dependent approach could be applied in social environments, to support the user’s awareness of the proximity and presence of others
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