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El futuro de la población peruana: problemas y oportunidades / The future of the Peruvian population: problems and opportunitiesAramburú, Carlos E., Mendoza, Walter 10 April 2018 (has links) (PDF)
This paper presents the trends and characteristics of the Peruvian population up to 2050 based both on official statistics and author’s estimates. Issues discussed include growth, changes in vital rates, age structure, the demographic bonus, ageing, migration and distribution. Policy implications of these demographic trends are also discussed. / El artículo presenta las tendencias y características de la dinámica poblacional peruana a 2050 usando las últimas proyecciones del INEI y estimados del autor. Se abordan los temas de crecimiento, cambios en las tasas vitales, en la estructura por edades, el bono demográfico, el envejecimiento, la migración y la distribución en el territorio. Se ofrecen algunas reflexiones sobre la implicancia de esta dinámica para las políticas públicas.
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Impact of Mandatory Sentencing Policies on Alabama's Prison PopulationsStewart, Stephanie Elaine 01 January 2019 (has links)
State prison systems, particularly in the Southern US, have been overpopulated for decades with unlikely support for building new prisons which has led to overcrowding. Policy makers, however, have adopted mandatory minimum policies that include harsher sanctions for habitual offenders which exacerbated the problem of overcrowding, yet little is understood about how sentencing reform is associated with overpopulation. Using Clear and Schrantz conceptualization of prison population change, the purpose of this quantitative descriptive study was to understand how one prison system in a southern state was impacted over a 10-year period by the implementation of mandatory minimum sentencing requirements. Data were collected from publicly available resources from a state department of corrections and state law enforcement agencies related to crime rates, sentence terms, parole rates, and prison population for the years 1993 through 2013. These data were analyzed using descriptive statistics, including measures of central tendency and visual examination of line plots. Findings indicated that the state's prison population did not change following the 2003 enactment of mandatory-minimum sentencing. Though no changes in prison population trends were observed, further testing may be considered to better understand the relationship between sentencing reform efforts and strengthened provisions to the laws regarding habitual felony offenders. The implications for positive social change stemming from this study includes recommendations to lawmakers to expand research and use the results as the basis of future decisions to either revise or eliminate mandatory sentencing policies taking into consideration crowding in state prisons.
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Devine qui vient dîner … : graines des villes et graines des champs, ou l'impact de l'agriculture péri-urbaine sur les oiseaux des jardins / Guess who comes to dinner ... : seeds of towns and seeds of fields, or the impact of suburban agriculture on garden birdsPierret, Pauline 11 January 2018 (has links)
Nourrir les oiseaux dans les jardins privés est une activité très répandue en Occident. Elle fournit une remarquable opportunité de recherche et de suivi des populations d’oiseaux en hiver sur de larges échelles spatio-temporelles, en impliquant les citoyens dans des programmes de science participative. Nous avons utilisé le programme Oiseaux des Jardins, un programme de science participative coordonné par la Ligue de Protection des Oiseaux, pour étudier sur une grande échelle spatiale les variations d’abondance d’oiseaux en hiver dans les jardins qui fournissent de la nourriture. Le but de cette thèse est de comprendre quels paramètres peuvent expliquer les visites des oiseaux dans les jardins en hiver, saison traditionnellement considérée comme la plus décisive pour leur survie. Nous montrons que les jardins distribuant de la nourriture, proches de milieux agricoles intensifs, attirent les oiseaux en réponse à une raréfaction des ressources alimentaires naturelles, causée par l’intensité des pratiques agricoles. Cette relation est encore plus forte pour les espèces spécialistes des milieux agricoles. Les variations d’abondance d’oiseaux dans les jardins fluctuent selon les années et les conditions météorologiques, sans présenter de pattern de réponse commun entre espèces, en raison de leur biologie et écologie différentes. Ce suivi des oiseaux en hiver reflète également la tendance négative de population de plusieurs granivores, connue en France ou en Europe en période de reproduction, confirmant que l’utilisation des jardins avec mangeoires est un bon moyen de suivre les tendances des populations d’oiseaux. Nous suspectons que les variations d’abondances à l’échelle spatiale peuvent également refléter l’effet d’activités humaines, telles que le braconnage des passereaux, mais un travail supplémentaire est nécessaire pour confirmer cette hypothèse. Les résultats de cette thèse peuvent également aider au maintien des espèces granivores en déclin, en apportant des conseils adaptés à la distribution de nourriture de substitution pour les oiseaux dans les paysages agricoles intensifs, tout en continuant à engager le public dans le suivi et la protection de la nature. / Supplementary feeding of wild birds in private backyards is a globally widespread pastime. It provides a wonderful opportunity for research and survey of winter bird populations at spatial and temporal large-scales by involving householders in citizen science programs. We used data from the French national garden birdwatch scheme, a citizen science program operated by the Ligue de Protection des Oiseaux, to study winter bird abundance variations in gardens which provided food supply, at a large spatial scale. This thesis aims to understand which factors influence the visit of gardens by birds during winter, a season traditionally pointed out to have the greatest impact on passerine survival. We highlighted that gardens with feeders located close to intensively cultivated farmland attract birds as a response of the countryside natural resource scarcity leads by intensive agricultural practices. This relationship being stronger for farmland seedeater species. Variations in the use of garden by birds also fluctuate between years and with weather conditions, but the variations were not similar among species. This being consistent with the expected influence of their ecological and biological differences. This garden bird survey in winter also reflected the global negative trends observed for some granivorous species in France or Europe during the breeding season, confirming that the use of garden bird feeders by wild bird species offers a new tool to survey the global population trends. We also suspect that variation in abundance could mirror spatial differences, and maybe mirror human activities impacts such as poaching, but this part requires further investigation. Finally, our work could be beneficial for maintaining declining seedeater species, by advising to supply birds with winter food in garden located in intensive agricultural landscape, while continuing to engage the public with nature.
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Genetics, demography and modeling of freshwater mussel (Bivalvia: Unionidae) populations in the Clinch River, U.S.A.Jones, Jess W. 17 April 2009 (has links)
Genetic variation was examined in two endangered mussel species, Epioblasma brevidens and E. capsaeformis, and a common species Lampsilis fasciola, in the Clinch River, TN, by screening mitochondrial DNA (mtDNA) sequences and nuclear DNA microsatellites. These species use fish hosts with varying dispersal capabilities, ranging from low, moderate, and high, respectively. Patterns of mtDNA polymorphism exhibited different trends for long-term population sizes for each species during the Holocene (~10,000 ya to present); namely, E. brevidens has declined over time, E. capsaeformis has remained stable, and L. fasciola has expanded. Long-term effective population size (Ne) was smallest in E. brevidens, intermediate in E. capsaeformis, and highest in L. fasciola. Moderately diverged mtDNA lineages, perhaps indicative of secondary contact, were observed in E. brevidens and E. capsaeformis. High levels of gene flow (Nm) were estimated among demes of L. fasciola using traditional F-statistics and likelihood estimates of Nm, whereas such metrics were lower in E. brevidens and E. capsaeformis. Data are consistent with population dynamics and life history traits of each species and their fish hosts.
Age, shell growth, and population demography of Epioblasma brevidens, E. capsaeformis, and Lampsilis fasciola were studied from 2004-2007 in a 32-km reach of the Clinch River, TN. Observed maximum age and length of E. brevidens was 28 y and 71.5 mm for males and 11 y and 56.6 mm for females; of E. capsaeformis, 12 y and 54.6 mm for males and 9 y and 48.6 mm for females; and of L. fasciola, 45 y and 91.3 mm for males and 13 y and 62.6 mm for females. For all three species, observed maximum age and length was greater among males than females. Estimated population size in this river reach was approximately 43,000 individuals for E. brevidens, 579,000 individuals for E. capsaeformis, and 30,000 individuals for L. fasciola. Mean recruitment y-1 of 1 y-old E. brevidens ranged from 7.1% to 20%, of E. capsaeformis from 4.0% to 32.4%, and of L. fasciola from 5.8% to 25.6%. Population growth rate y-1 was 24.9% for E. brevidens, 34.6% for E. capsaeformis, and -22.4% for L. fasciola. Mortality rates of females were higher than for males of E. capsaeformis and L. fasciola, but not E. brevidens. Juvenile mussels were collected but temporally and spatially variable in occurrence, and a significant component of the age-class structure of all three species. Recruitment was very high during 2006-2007 for E. capsaeformis and other species, likely due to low river discharges in the spring-summer of 2005-2007. Surplus individuals of E. brevidens and E. capsaeformis are currently available to conduct translocations for restoration purposes.
Population modeling of Epioblasma brevidens and E. capsaeformis in the Clinch River was conducted to determine suitable harvest levels for translocation of sub-adults and adults, and to determine quantitative criteria for evaluating performance and recovery of extant and reintroduced populations. For both species, the recommended annual harvest was <1% of local population size to minimize risk of decline. Reintroduction modeling indicated that size of the initial population created during a 5 y build-up phase greatly affected final population size at 25 y, being similar to size at the end of the build-up phase, especially when expected growth rate was low, (e.g., 1-2%). Excluding age-0 individuals, age-1 juveniles or recruits on average comprised approximately 11% and 15% of a stable population of each species, respectively. The age-class distribution of a stable or growing population was characterized by multiple cohorts, to include juvenile recruits, sub-adults, and adults. Molecular genetic and demographic data indicated that the ratio of Ne/Nc was ~5% for both species. Based on this ratio and predicted declines of genetic variation at different population sizes, target sizes for reintroduced or recovered populations of each species should be ≥5,000 individuals (Ne=250) and ≥10,000 individuals (Ne=500), respectively, and should be comprised of multiple smaller demes spread throughout a river. Populations of both species are currently large enough to sustain harvest for translocation and reintroduction purposes, offering an effective species recovery strategy. / Ph. D.
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THE ROLE OF SHARKS IN MARINE ECOSYSTEMS: EVALUATING OVEREXPLOITED MARINE FISH COMMUNITIES TO DETECT LONG-TERM EFFECTS OF PREDATOR REMOVALFerretti, Francesco 15 December 2010 (has links)
Elasmobranchs are among the oldest and most successful predators in the ocean, yet one of the most vulnerable to the direct and indirect effects of fishing. Many populations are rapidly declining around the world, and an increasing number is listed as threatened or endangered. The broader ecosystem consequences of these declines, and whether other marine predators can replace sharks, are open questions. In this thesis, I used a diverse set of data and modeling techniques to analyze long-term changes in elasmobranch populations in the Mediterranean Sea, and the consequences of shark declines on marine ecosystems.
Because of its long history of fishing, the Mediterranean offers a unique perspective on the response of marine communities to exploitation over long time scales. Here, I reconstructed the history of elasmobranch exploitation over the past 200 years in pelagic, coastal and demersal communities. Results were combined meta-analytically to derive a general pattern of change for the entire region. Overall, I detected multiple cases of regional species extirpations, a strong correlation between historical intensity of exploitation and the stage of community degradation, and some cases of compensatory species increases. My results suggest that compared to other marine ecosystems worldwide, the Mediterranean Sea might be in an advanced stage of overexploitation.
To gain more general conclusions about the patterns and consequences of shark declines in the ocean, I reviewed and reanalyzed documented changes in exploited elasmobranch communities around the world, and synthesized the effects of sharks on their prey and wider communities. This work revealed that sharks are abundant and diverse in little exploited or unexploited marine ecosystems but vulnerable to even light levels of fishing. The decline in large sharks has reduced natural mortality in a range of their prey, contributing to changes in abundance, distribution, and behaviour of marine megafauna that have few other predators. In some cases, this has resulted in cascading changes in prey populations and food-web structure. Overall, my thesis greatly enhanced our knowledge about the critical state of elasmobranchs in the Mediterranean Sea and the consequences of the declines of these important marine predators on marine ecosystems.
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Chronic heart failure beyond city limits: an analysis of the distribution, management and information technology solutions for people with chronic heart failure in rural and remote AustraliaClark, Robyn A January 2007 (has links)
Chronic heart failure (CHF) is defined as a complex clinical syndrome that is frequently, but not exclusively, characterised by objective evidence of an underlying structural abnormality or cardiac dysfunction. CHF affects up to 3% of the adult population and this rate is consistent throughout the developed world. In spite of the proven efficacy of treatments, there is a common theme of low implementation rates for recommended therapeutic guidelines. In Australia, where access to specialist CHF management is limited, the burden of care, for the 40% of CHF patients living outside capital cities falls predominantly onto community-based general practitioners (GPs). Unfortunately, there are diminishing numbers of GPs in rural and remote regions and this has created an apparent dual deficit in terms of equitable access to primary and specialist care for the CHF population living in these areas. The purpose of this research was to determine, in a series of themed studies, the population distribution, management and potential information technology solutions for CHF in rural and remote Australia. Appropriate methods were utilised for each study and included epidemiological studies, a quantitative analysis of a large practice audit, geo-mapping, a systematic review, a case study review and a qualitative analysis of participant feedback and clinical notes.
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Factors Influencing Indiana Residents' Level of Interest in Engaging with Purdue UniversityAshley E Rice (6615803) 15 May 2019 (has links)
The land-grant university system was founded in the 19th century as a public means to help improve people’s everyday lives. A century and a half later, the challenges that the public faces to live a quality life are constantly changing, creating a need for the land-grant system to respond and adapt to continue to fulfill its mission. While the literature contains a wealth of conceptual papers addressing the role and mission of land-grant universities, relatively few papers could be found that reported empirical data or proposed and tested metrics for public engagement constructs. The current study sought to address this void in the literature through the investigation of factors influencing Indiana residents’ level of interest in engaging with Purdue University. Mail survey methods were used in which up to three contacts were made with adult members of 4,500 Indiana households identified through address-based sampling. Stratified random sampling was employed to ensure adequate rural household participation for other project purposes. Usable responses were received from 1,003 households representing 87 Indiana counties for a total response rate of 26%. <br><div><br> </div><div> A theoretical perspective was developed from Public Sphere Theory and the social science writings of Jurgen Habermas and Alexis de Tocqueville. Descriptive findings revealed some to moderate concerns about community and social issues such as affordable health care, violent crime, pollution and prescription drug abuse. Moderate levels of anomie, or perceived social disconnectedness, were also reported by respondents. Several items tapped respondents’ past levels of interaction with and current perceptions of Purdue University. Nearly a fifth of respondents reported interacting with Purdue University by having visited a website for news or information, followed by interacting with a Purdue University Extension professional. Regarding perceptions of Purdue University, the results of this study revealed relative consensus among respondents that Purdue University makes a positive contribution to the state of Indiana through its educational, research and outreach programs. For a majority of the perceptual items regarding Purdue University, more than one-third of the respondents neither agreed nor disagreed with the statement, suggesting some areas in which the university might improve its reputational standing with Indiana residents in the future. Nearly one-quarter to about half of the respondents indicated interest in topical areas addressed by Purdue Extension programs as well as an interest in engaging with the university. Respondents reported the highest levels of interest in free Extension programs in their local area, followed by the topics of science and technology, health and well-being, and gardening.</div><div><br> </div><div> A predictive model of respondent interest in engaging with Purdue University was developed and tested using binary logistic regression procedures. The model was shown to be of modest utility in accounting for variance in respondent interest in engaging with Purdue University, explaining 12% to 16% of total variance. Past interaction with Purdue University, perceived level of concern for social and community issues, and highest level of education were the strongest predictors in the model.</div><div><br> </div><div> The current research was completed in 2019 as Purdue University celebrated its 150th anniversary. Results and implications of this study provide important insight into current engagement levels, concerns and perceptions of residents within the state of Indiana, whom the university is mandated to serve. One of the study’s primary contributions is the establishment of baseline engagement data on current levels of Indiana residents’ interest in engaging with Purdue University on selected topics. Findings from this study could be of benefit to university administrators, faculty, staff and Extension professionals in assessing and improving future programming and setting strategic priorities. This study also adds to the conceptual and empirical body of literature, which may help inform future public engagement efforts at other land-grant universities. Periodic social science and public opinion research is needed to keep pace with the changing needs and perceptions of Indiana residents. Different data collection modes should be utilized to reach more audience segments and add to the growing knowledge base of public engagement.</div>
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