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1

Olszewski, Laura Michalec. "Expansion of U.S. Immigration and Customs Enforcement's Criminal Alien Program in the war on terror". Thesis, Monterey, Calif. : Naval Postgraduate School, 2008. http://edocs.nps.edu/npspubs/scholarly/theses/2008/Dec/08Dec%5FOlszewski.pdf.

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Thesis (M.A. in Security Studies (Homeland Security and Defense))--Naval Postgraduate School, December 2008.
Thesis Advisor(s): Bach, Robert ; Brannan, David. "December 2008." Description based on title screen as viewed on January 28, 2009. Includes bibliographical references (p. 77-86). Also available in print.
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2

Tenbaum, Stephan. "Characterization of alien isoforms in vertebrates Charakterisierung von Alien-Isoformen in Vertebraten /". [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965239225.

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3

Jung, Jaekyung. "Critical play : alien contact". Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/61559.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 25-26).
I argue that the necessity of emancipating the Situationist International (SI) from the historical notion of it as the last movement of the avant-garde in order to take over the spirit of the SI. I claim that necessity of strategically announcing the concept of the Post- Situationist in order to interrupt existing perceptions of the SI. I propose "play" as a major direction in revitalizing the aesthetic sensibility of dehumanized citizens who live in the "spectacle", as defined as the Situationists, of capitalist society. I also propose to reinvent humanized daily life based on studying French philosopher Jacques Ranciere's aesthetical politics and Marxist theorist Guy Debord's theories on spectacle. Simultaneously, I investigate "critical play" as my central tactic in reconnecting social neurons among atomized citizens to re-energize human creativity, a core agent in progressing social development. Lastly, I demonstrate one of my research projects performed over the last two years in the program in Art, Culture, and Technology. In terms of critical play, I am seeking the potentiality of Post Situationist strategies.
by Jaekyung Jung.
S.M.
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4

Charlebois, Julia. "Pollinator-Mediated Interactions Between Alien and Native Plants: Alien Status and Spatial Relationships". Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36637.

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The introduction of species outside of their native ranges has been extensively studied in ecology. Particular attention has been paid to examining interactions between alien and native plants, and a large proportion of this attention has focused on pollinator-mediated interactions. In order to interact through pollinators, plants must co-occur, coflower, and share pollinators; studies investigating pollinator-mediated interactions between alien and native plants frequently make fundamental assumptions about the definition of these prerequisites to pollinator-mediated interaction. The present analysis examines assumptions about plant co-occurrence and the effects that these assumptions have on study outcomes. In Chapter 2, I present the results of a meta-analysis of 76 studies which overturns previous findings that pollinator-mediated interactions between plants can be predicted on the basis of whether the neighbour is an alien, phylogenetic distance, or floral trait similarity. Moreover, I demonstrate that the spatial definition of the control group (i.e. the distance between the group of focal plants that ‘do not co-occur’ with the alien/alternate neighbour species and the nearest individuals of that neighbour species), and the spatial arrangements of plants within their treatment groups (i.e. the relative placement of the group of focal plants that ‘co-occurr’ with the neighbour species), both have a significant impact on the outcome of pollinator-mediated interactions between alien and native plants. I also emphasize evidence of bias in the selection of study systems and in the process of publication. In Chapter 3, I present the results of a field experiment testing the role of distance between interacting plants in determining patterns of visitation by insects. The results of this analysis are suggestive of visitor functional group-dependent effects but limited by low power. In both Chapter 2 and Chapter 3, I show that heretofore unexamined assumptions about definitions of co-occurrence of plants may be introducing bias into studies of pollinator-mediated interactions between plants, and that facilitation and competition between plants for visitation may be linked across different spatial scales.
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5

Henson, Katherine Sarah Elaine. "The restoration of ecological interactions : considering plant-pollinator, host-parasite and alien-alien interactions". Thesis, University of Bristol, 2007. http://hdl.handle.net/1983/a49626c2-783c-460b-addd-d124175070b1.

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6

Connelly, Janet Hosier. "Horseshoe Crabs-Ancient Alien Protectors". Thesis, The George Washington University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10118697.

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Ancient Alien Protectors is an exhibition that tells the story of the wonders and benefits of horseshoe crabs. What are they and why should anyone care about them? Researching the topic revealed that more often than not an inhabitant of the Western Shore or any of the landlocked geographical locations in the United States has limited knowledge about horseshoe crabs. Their kind has inhabited our Earth for over 475 million years. They have outlasted over ninety-nine percent of all the species that ever swam or walked on the planet but are now in peril due to human activity. They have been harvested for farmers to make fertilizer for crops, chopped up as bait for fishermen, and captured and bled by biomedical companies. Their copper-based blue blood is used to produce a life-saving product that is hypersensitive to bacteria. The injectable drugs and medical devices that come in contact with our blood must be tested for the presence of toxins, horseshoe crabs have now become an invaluable commodity to modern medicine.

Horseshoe crab eggs are a food source for many crustaceans and fishes. Their eggs are an integral part of the diet of many shorebirds, allowing them to refuel and gain weight before continuing their journey northward to the Arctic. Disappearance of the horseshoe crab from the waters of the Atlantic Ocean would be a critical blow to the life-sustaining connection between members of local ecosystems.

The goal of this research is to create an exhibition that sparks an awareness about how we are an intrinsic part of the natural world. The exhibition is designed so that visitors will have an opportunity to enter a museum located in the Delaware Bay region, the natural setting where the largest population of horseshoe crabs are born, grow to maturity, and reproduce. Visitors can immerse themselves in an environment that will stimulate their senses as well as their mind and leave inspired to engage in the conservation and protection of this resilient species. The proposed site will also house a research facility collocated with the museum to foster cooperation and knowledge sharing among scientists. A partnership between the conservation and medical communities would strengthen the commitment to finding better ways to strategically manage and preserve this precious living resource.

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7

Mullins, Shena. "Alien on a Savage Planet". ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1934.

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This paper details the process of creating the UNO Graduate thesis film Alien on a Savage Planet. Each major step in the filmmaking process is covered: screenwriting, producing, directing, cinematography, sound, production design, costumes, hair and makeup, workflow, editing, color correction, music and post- sound. A comprehensive assessment of the filmmaking process and the successes and failures of the project are discussed in length.
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8

Jones, Emily Elizabeth. "Alien tree's sugary S.O.S. exploited by thieving tramp ant: unidirectional benefit in an alien, tritrophic mélange". University of Dayton / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1565107639230889.

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9

Coates, Stephen. "Alien nation: David Hare's history plays". Thesis, University of Canterbury. English, 1989. http://hdl.handle.net/10092/4579.

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This thesis will examine seven plays by David Hare, which together constitute a social history of Britain since the Second World War. Hare's main project is to demonstrate to the members of his audience, most of whom will be "middle class", that they are psychologically damaged by the capitalist-patriarchal system. The ideological fictions which have evolved to justify the existing structure of society and to discourage the oppressed from challenging that structure create psychological contradictions which cannot be resolved without radical social change. The middle classes are suffering from alienation no less than the oppressed, even though they may not be aware of it, and the loss of their privileged economic and political positions would be a small price to pay for the greater happiness which would accompany the removal of these contradictions. The history plays are therefore an attempt to create a counter-hegemony, by undermining established myths about the nature of contemporary British society. Chapter 1 provides brief accounts of British political theatre since the 1960s and the origins of Western Marxism. It also introduces the Marxist concepts of alienation, ideology and hegemony (in particular, the theories of Antonio Gramsci and Herbert Marcuse), relating them to the oppression of women as well as the oppression of classes. Chapters 2-8 examine the plays separately in the light of these concepts, with different emphases determined by the content of the plays. Specific issues which are examined in these chapters include the loss of individuality in contemporary capitalism, and the stultifying effects of certain current myths - about the transcendent power of romantic love, the liberating force of the sexual act, the social revolution which took place during World War Two and the alleged benevolence and contentment of the 1950s. Chapter 9 provides some brief comments on political theatre in general, and realist political theatre in particular, and considers how far the intentions of the playwright may be sabotaged by theatrical conventions and the preconceptions of the audience.
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10

Shaw, Maya. "⏁⊑⊬⟊, ⏁⎎⎅☌⊬⍜⍀: Alien Languages In Science Fiction". Thesis, Stockholms universitet, Engelska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-194006.

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Language is a central concern of science fiction. From first contact to interstellar warfare, stories about aliens inevitably raise questions of communication. But how do we conceive of alien languages within the constraints of human language? And what do depictions of alien languages reveal about our own language use? Several studies have established the significance and magnitude of the theme of language in (predominantly twentieth century western) science fiction. Building on these studies, I combine macro-analysis with close reading to argue that these alien languages fall on a spectrum of alterity. Within this spectrum, I organise these languages into three distinct gradations of alterity: they help to define their speakers as alien people, creatures or inscrutable beings. The languages of alien 'people’ are structurally similar to our own, and explore the socio-political relationship between language and culture. Those of ‘creatures’ are radically, physically unlike human languages and explore the boundary between humans, animals and aliens. Finally, the languages of ‘beings’ are incomprehensible and prone to spiritualisation. They bring to light the aspects of experience we deem beyond language. This typology provides a framework through which to explore the major themes and questions regarding language, humanity and alterity in science fiction. By presenting these categories in increasing degrees of alterity, I aim to demonstrate that language, like the figure of the alien, is a fundamentally anthropocentric concept. Each category identifies different facets of our language use that simultaneously alienate and define us.
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11

Reibel, Tracy. "Alien possession: constructions of Australian identity". Thesis, Reibel, Tracy (1999) Alien possession: constructions of Australian identity. PhD thesis, Murdoch University, 1999. https://researchrepository.murdoch.edu.au/id/eprint/50723/.

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This thesis involves an examination of a range of historical discourses and how they have contributed to the shape and definition of constructions of cultural identity in Australia. The impact of such constructions on the socio-cultural environment has created a situation where Australia is internationally regarded as a just, fair, and tolerant democratic society but concomitantly has ensured a continuing state of colonisation for the Indigenous peoples of Australia and denied them a history beyond I 788. This highlights an inconstancy in the representation of Australian society that has privileged certain forms of cultural production and limited the ability of the society to adequately embrace its culturally diverse make-up. It is against the background of a continuing colonial imperative that many of the arguments presented in this thesis will be made. Cultural production is the way in which all facets of social, political, and economic life are accounted for in the realisation of unique meaningfulness for a culture. When these processes are selective and discriminatory a sense of disruption will become evident over time, as individuals and groups are marginalised and alienated from the dominant culture. While justice and tolerance may long have been ideals for the Australian community, and have contributed significantly to the endurance of Australia as a unique socio-cultural environment, they are ideals that have often been circumscribed by influential ideological assertions. For example, the ideology of nationalism and national identity in particular has been the driving force of Australian society since the late I 800s and has very much defined the cultural, social, political and economic domains. The ideological circumscription that nationalism entails has erected barriers to the cohesion of Australian society, in that it has promoted a false homogeneity as a 'truth' of representation. In order to investigate the questions raised throughout the thesis a number of theoretical concepts, or tools, have been chosen to address the problematic nature of defining cultural identity; the cultural condition; and the meaning and impact of multiculturalism. The tools chosen primarily stem from the works of Jean-Franyois Lyotard, Michel Foucault, Gayatri Chakravorty Spivak, and Benedict Anderson. The thesis posits that the imagining of the future Australian republic requires thoughtful engagement with all facets of the socio-politico-cultural environment including those historical events that may have been seen as undesirable or unnecessary by the dominant cultural memory. It is not the history itself, however, that is in view but the ways in which representations of such history have been responsible for distorted or false constructions. It is the goal of this thesis to emphasise a more inclusive view of Australian history in order to enable a positive future direction for all Australian citizens - now and in the future. The thesis concludes by drawing the threads of the discussion together and considers how the Australian community can resist the temptation to accept a less tolerant social context and determine positive ways in which to transform the socio-cultural environment to develop an inclusive, just, and ethical cultural milieu.
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12

Gray, David. "Understanding the Alien in Scheler's Phenomenology". OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2396.

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This work argues that Scheler’s phenomenology has the resources to overcome the problem of understanding one of a foreign ethos (i.e., alien) as alien. It does so in three stages. After the introduction, the second chapter provides an exposition of the key intentional structures and horizons to Scheler’s “emotive sphere” or “order of the heart” (ordo amoris). This provides a general orientation into the role emotions have in to our cognitive life. The third chapter sets the stage for the fourth through an analysis of how the person is given to me, with an eye towards their ordo amoris. The fourth chapter picks up where the third leaves off: that humility and co-experiencing are essential to a loving understanding of the alien. While there are obstacles to understanding the alien, such as depersonalization, these can be overcome either through a sympathetic response to spiritual feelings, or more generally in a humble spiritual love. Such a love opens me to their exemplars and their concrete person, whereas lesser forms of love and sympathy render the alien’s acts too abstractly.
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13

Brodie, James Douglas. "Alien presences : digital technology and imperialism". Thesis, Queensland University of Technology, 1999. https://eprints.qut.edu.au/35910/1/35910_Brodie_1998.pdf.

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I am a visual artist, a printmaker, and I have been using computer imaging processes in my studio work since 1987. This paper is a supporting document for my submission of creative work which involves incorporating digital imaging into traditional fine arts processes such as printmaking, drawing and collage. The the thoretical basis for my studio production is a combination of cultural studies and postcolonialism. The images I produce re visual summations or examinations of the position of the other in terms of mainstream culture. My creative work interrogates three interrelated themes involving technology and cultural transformation. The first theme is an examination of how visual artists regard technology per se, and the incorporation of digital processes in the production of static images by visual artists working in the Eurocentric tradition in the fine arts of painting and printmaking. The second theme examines the position occupied by specific creative individuals in mainstream culture whose practice places them on the margins of that culture. These individuals occupy the position of the outsider or the other in terms of mainstream cultures. The third theme investigates the phenomenon of technofear in contemporary society, which results from the integration of digital processes in the development of globalised mainstream or imperial metanarratives and their relationship to peripheral individuals and cultures.
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14

Martini, Chandra. "Alien others : speculative hybrids in imaginary worlds". Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43381.

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Hybridity plays a principal role in both J. R. R. Tolkien’s The Silmarillion and Octavia E. Butler’s Xenogenesis trilogy, crystallizing in the treatment of the origin of species. Through these texts I investigate how the generic condition of speculative fiction (SF), in its claims to unreality, opens up an imaginative space in which to excavate hybridity as a site of tension between the concepts of race and species. I draw on the theoretical constructs of hybridity and posthumanism, particularly as formulated by Robert Young in the first case and Cary Wolfe in the second, to argue that these concepts are fundamentally interdependent in post-Enlightenment Western humanism. Both Young and Wolfe show how a tradition of Western humanism has enabled, justified and managed the oppression of both animal and racial Others by casting them as subhuman. Tolkien’s and Butler’s representations of hybridity are haunted by historical manifestations of this logic; Tolkien’s Half Elves are informed by the threat of the Nazi programme of racial purification, and Butler’s human-alien hybrids recall a legacy of slavery and a contemporary discourse of genetics. By blurring the boundary between race and species, they expose the fact that race and species are always already mutually constituting. Drawing on Butler’s and Tolkien’s texts, I argue the importance of integrating an analysis of race into the efforts begun in posthumanist animal studies to build a more honest and ethical way of thinking through the relationship between our species and others.
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15

Schonegevel, Lucille. "Modelling alien vegetation invasions and clearing strategies". Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52341.

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Thesis (MSc)--Stellenbosch University, 2001.
ENGLISH ABSTRACT: The burgeoning problem of alien plant invasions in South Africa necessitates effective decision-making based on an understanding of the complex processes that govern these invasions. Due to the spatial nature of the problem, this study explored the use of Geographic Information Systems and spatial models for predicting the spread of alien vegetation and assessing the effectiveness of clearing strategies. The Spatially Explicit Individual Based Simulation (SEIBS) model was identified as a potentially useful tool for alien plant management. This thesis documents the further investigation and development that was necessary before recommendations could be made regarding the future use of the model. The landscape version of the SEIBS model was adapted to allow for the convenient input and output of spatial data, making it possible to simulate invasions in different areas. An ArcView extension was developed in order to facilitate the pre- and post-processing of the spatial data required and created by the model. Changes were also made to the fire routine of the model. The new version of the model was called Clear. A series of model tests for Pinus pinaster were conducted to assess the sensitivity of the Clear model to spatial resolution, initial spatial fragmentation and heterogeneity. These tests revealed that the model was sensitive to changes in resolution and needed to be reparameterised when using different resolutions. The initial level of fragmentation was shown to have a major influence on the invasion rate. Although greater levels of spatial heterogeneity with respect to vegetation age did not significantly affect the spread rate, it did increase the effectiveness of clearing strategies based on clearing juvenile or sparse vegetation. Based on these tests, it is concluded that the model can be readily applied to different areas, provided the influence of spatial characteristics is understood and accommodated. The Clear model was shown to be a useful tool for evaluating clearing strategies and for investigating invasion rates. It is recommended that the model be introduced to a wider audience, in order to obtain user feedback and further improve the accessibility of the model.
AFRIKAANSE OPSOMMING: Die toenemende probleem van uitheemse indringerplante in Suid Afrika, noodsaak effektiewe besluitneming wat gebaseer is op 'n begrip van die ingewikkelde prosesse wat indringing beheer. As gevolg van die ruimtelike geaardheid van die probleem, is die gebruik van Geografiese Inligtingstelsels en ruimtelike modelle vir die voorspelling van die verspreiding van indringerplante en die evaluasie van die effektiwiteit van opruimingstrategieë in hierdie studie ondersoek. Die Spatially Explicit Individual Based Simulation (SEIBS) model is as 'n moontlike geskikte hulpmiddel vir die bestuur van uitheemse indringerplante geïdentifiseer, alhoewel verdere ondersoeke en ontwikkeling nodig was voordat aanbevelings vir die gebruik van die model gemaak kon word. Vir hierdie studie is die landskapweergawe van die SEIBS model aangepas om die maklike toevoer en afvoer van ruimtelike data te fasiliteer. 'n ArcView uitbreiding is ontwikkel om met die voor- en naprosessering van ruimtelike data, wat deur die model gebruik en geskep is, te fasiliteer. Veranderinge is ook aan die vuur sub-roetine van die module gemaak. Die nuwe weergawe van die model word Clear genoem. 'n Reeks toetse is vir Pinus pinaster gedoen om die sensitiwiteit van die Clear model te toets teenoor ruimtelike resolusie, aanvanklike vlak van versnippering en vlak van heterogeniteit. Vanuit die toetse het dit geblyk dat die model sensitief was ten opsigte van verandering in resolusie en dat die model se parameters verstel moes word wanneer verskillende resolusies gebruik word. Daar is ook gewys dat die die vlak van aanvanklike versnippering 'n groot impak op die verspreidingstempo het. Alhoewel hoër vlakke van ruimtelike heterogeniteit teenoor plantegroei nie 'n merkbare impak op die verspreidingstempo gehad het nie, het dit wel die effektiwiteit van opruiming-strategieë, gebaseer op die opruiming van jong of yl verspreide plante, verbeter. Die gevolgtrekking wat uit die toetse gemaak kan word is dat die model geredelik op verskillende areas toegepas kan word, op die voorwaarde dat die invloed van ruimtelike eienskappe in ag geneem word en in berekening gebring word. Dit word aanbeveel dat die model wyer bekendgestel word om sodoende gebruikersterugvoer te bekom.
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16

Koebner, Robert Max David. "Controlled introgression of alien chromatin into wheat /". Title page, table of contents and abstract only, 1985. http://web4.library.adelaide.edu.au/theses/09PH/09phk77.pdf.

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17

Harvey-Wilson, Simon Brian. "Shamanism and alien abductions : a comparative study". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2000. https://ro.ecu.edu.au/theses/1389.

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Some UFO researchers (ufologists) claim that being abducted by aliens can be compared with shamanic initiation experiences in traditional societies in that both types of experience may be similarly transformative, leading to a more spiritual or animistic world-view, a deep concern for the environment and the development of paranormal abilities such as healing. This qualitative study is designed to investigate the validity of such claims. The research aim is to see whether the experiences and subsequent world-view of eleven alien abductees (eight women and three men) from a local abduction support group are similar to those of the typical shaman and, if so, what those similarities are. To do this, material gathered from in-depth interviews with the abductees is compared with the anthropological literature on shamanism, especially shamanic initiation experiences, from all parts of the world.
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18

CHINCHIO, ELEONORA. "DISEASE RISK ASSESSMENT OF INVASIVE ALIEN SPECIES". Doctoral thesis, Università degli Studi di Milano, 2021. http://hdl.handle.net/2434/821735.

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Increased global trade and travel have led to a rise in the number of invasive alien species (IAS), i.e. species introduced by humans in geographic areas where are not naturally found, worldwide. Despite the recognized role of wildlife, as well as of wildlife translocations, in the emergence and re-emergence of infections of public health significance, IAS remain mainly studied for their environmental impacts, and their disease risk towards humans and animals is still largely neglected by health professionals. The main aim of this thesis is therefore to cover this gap by setting the ground for a new “invasion epidemiology” field, and this has been done through two main steps: the review and analysis of both the mechanisms underlying IAS disease risk and the information available in literature on IAS pathogens, and the development of a standardized qualitative disease risk assessment method, applicable to different geographic contexts, to assess the risk of mammal IAS to impact on human and animal health. First, I reviewed the existing biological and ecological literature on IAS to identify the main mechanisms by which animal IAS may affect disease risk in their area of release. IAS resulted to potentially affect disease risk both directly, by acting as hosts of infectious agents, thus possibly leading to the introduction of new pathogens, and/or the amplification of endemic ones, or indirectly, by altering the ecosystem equilibrium, through competitive and trophic interactions with native host species or the modification of local habitats. This literature review highlighted how IAS may have important health implications, which should be better acknowledged by people working in the human and animal health field, and how the mechanisms underlying the sanitary outcome of a biological invasion, and in particular indirect ones, are extremely complex, being the product of multiple factors. Acknowledging the important limitations of our current ability to predict possible health impacts driven by indirect mechanisms, I decided to address the issue of IAS disease risk by focusing specifically on IAS possible role as infectious agents’ host. As information on IAS pathogens is not systematized, preventing from knowing the amount and quality of available data to inform possible disease risk assessment procedures, I systematically reviewed the literature on the infectious agents of the main mammal species of European Union concern. Current knowledge on the pathogens harbored by mammal IAS was evaluated through different statistical approaches: the identification of the main factors associated with research intensity and the observed pathogen species richness, the estimation of the true helminth species richness, and a meta-analysis of prevalence of the pathogens of public and animal health significance. Results highlighted the existence of strong information gaps and biases in the way research on mammal IAS pathogens is carried out, the current underestimation of the amount of pathogens harbored by these species and high levels of uncertainty in the pooled prevalence of pathogens of public and animal health significance. However, the review confirmed that mammal IAS harbor pathogens of human and animal health significance, and therefore, the need to identify high-risk species. Considering that the existing knowledge gaps would have resulted in strong limitations in informing a risk assessment procedure, I developed a qualitative disease risk assessment methodology informed by expert opinion. This tool is specifically aimed at assessing IAS disease risk towards humans, domestic animal populations, and/or wildlife populations and allows to obtain a list of the pathogens of animal and human health significance that mammal IAS could transmit to a population of interest (directly or through the communities of local hosts), each with the related level of risk and uncertainty. Key features of the tool are its flexibility, being applicable to different contexts and for different purposes, and the high resolution of the mechanisms under assessment, which make possible for risk managers identifying the most critical pathogens and mechanisms involved in disease risk, allowing them to direct targeted actions and surveillance plans. Finally, the need to combine multiple likelihood estimates deriving from several pathways in an overall risk estimate led me to tackle a methodological aspect of qualitative risk assessment procedures, and I proposed a standardized method applicable in such cases, to reduce the subjectivity that relies in the different ways multiple estimates are currently combined.
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19

Schoeman, Colin Stefan. "Synergistic impact of invasive alien plants and the alien Argentine ant on local ant assemblages in the Western Cape". Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/21759.

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Thesis (MSc)--Stellenbosch University, 2008.
ENGLISH ABSTRACT: Alien trees, Pinus spp. and Eucalyptus spp., affect ants negatively in the Cape Floristic Region (CFR), a global biodiversity hotspot in South Africa. They reduce ant abundance and species richness, thus also changing ant assemblage structure. This is alarming, because almost 1300 species of plant species in the CFR are dispersed by certain indigenous ants, and thus there is concern for an indirect effect on indigenous plant assemblages. One of the most impacting ant species on seed dispersal is the invasive Argentine ant (Linepithema humile (Mayr)), which discards seeds outside its nest, where they do not germinate. Ten sites, on Vergelegen Wine Estate, were selected to explore these effects of alien plants. These varied from invaded to non-invaded sites. Each site consisted of six sampling points, which in turn consisted of four pitfall traps left out for seven days, during December 2005, February 2006, May 2006 and September 2006. Forty species of ant were sampled, and various analyses used to illustrate the comparative effects of plant invasion. All analytical methods showed that invasive alien plants had a significant impact on the abundance and richness of the ant species assemblage, by creating a dense canopy cover that changed the abiotic environment of the epigaeic ants’ habitat. Furthermore, increased alien tree invasion correlated significantly with Argentine ant abundances. The Argentine ant displaced Pheidole capensis and Camponotus spp., while it decreased the abundances of commonly-occurring indigenous ants, such as Lepisiota capensis and Plagiolepis spp. Displacement by the Argentine ant may be a result of indirect competition for food resources. The effects of invasive aliens are synergistic in that there is a cascade effects from initial plant invasions to subsequent animal invasion.
AFRIKAANSE OPSOMMING: Indringer bome, Pinus en Eucalyptus, affekteer miere op negatiewe wyse in die Kaap Florsitiese Streek (KFR), ‘n area in Suid Afrika van belang t.o.v. globale biodiversiteit. Hierdie uitheemse indringer bome verminder hulle hoeveelheid en spesies rykheid. Die bogenoemde is kommerwekkend omdat meer as 1300 plant spesies in the KFR versprei word deur miere. Die verandering in hoeveelheid en versameling van inheemse miere kan dus ernstige implikasies hê op die saad verspreiding van inheemse plant spesies. Een van die mees verwoestende effekte op saad verspreiding is veroorsaak deur die indringer Argentynse mier (Linepithema humile (Mayr)), wat sade neer werp buite hulle neste, waar hulle nie suksesvol kan ontkiem nie. Tien monsterings-tereine was geselekteer om die bogenoemde effekte te ondersoek op Vergelegen Landgoed. Hierdie het afgewissel van indringer tot skoon tereine. Elke terrein is op ses versamelings-plekke gemonster, met vier pitvalle, wat oopgelê het vir sewe dae gedurende Desember 2005, Februarie 2006, Mei 2006 en September 2006. 40 spesies van miere was gemonster. Indringer plante het ‚n betekenisvolle impak gehad het op die hoeveelheid en rykheid van die mier gemeenskappe, deur die skepping van ‚n dig baldakyn wat die abiotiese omgewing van die miere se habitat verander het. Die vermeerdering van indringer plante veroorsaak die vermeerdering van Argentyne miere. Kanonieke Mede-Respons Analise illustreer dat die Argentynse mier Pheidole capensis en Camponotus spp. verplaas het, terwyl dit ander inheemse mier getalle verminder het, soos Lepisiota capensis en Plagiolepis spp. Die verplasing deur die Argentynse mier mag die resultaat wees van indirekte wedywering vir hulpbronne. Die effekte van indringer species is dus sinergisties deur dat ‚n kaskade effek ontstaan vanaf plant tot dier indringer spesies.
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20

Döring, Lutz. "Erweckung zum Tod eine kritische Untersuchung zu Funktionsweise, Ideologie und Metaphysik der Horror- und Science-Fiction-Filme Alien 1-4". Würzburg Königshausen und Neumann, 2005. http://deposit.ddb.de/cgi-bin/dokserv?id=2756348&prov=M&dok_var=1&dok_ext=htm.

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Kob, Robert [Verfasser], Christian [Gutachter] Melle, Stephan [Gutachter] Diekmann y Wolfgang [Gutachter] Dubiel. "Funktionelle Untersuchungen der beiden Alien-Isoformen Alienα und CSN2 / Robert Kob ; Gutachter: Christian Melle, Stephan Diekmann, Wolfgang Dubiel". Jena : Friedrich-Schiller-Universität Jena, 2010. http://d-nb.info/1177664194/34.

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Döring, Lutz. "Erweckung zum Tod : eine kritische Untersuchung zu Funktionsweise, Ideologie und Metaphysik der Horror- und Science-Fiction-Filme Alien 1-4 /". Würzburg : Königshausen und Neumann, 2006. http://deposit.ddb.de/cgi-bin/dokserv?id=2756348&prov=M&dok_var=1&dok_ext=htm.

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De, la Fontaine Samantha. "Assessing the values and impacts of invasive alien plants on the livelihoods of rural land-users on the Agulhas Plain, South Africa". Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/95461.

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Thesis (MSc)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: Invasive alien plants (IAPs) are known for their detrimental impacts on biodiversity and ecosystem goods and services. A substantial body of research has contributed to our understanding of their impacts on ecology. In comparison the socio-economic aspects of IAPs, are not well understood. Additionally, valuation practises have usually excluded the positive and the non-monetary impacts (benefits and uses) that IAPs hold for local livelihoods. Holistic valuation has been regarded as imperative for decision-making and managerial frameworks. A study was conducted in Elim on the southern Cape coast of the Agulhas Plain, South Africa, which aimed to explore the various impacts of IAPs on the livelihoods of rural land-users. Individual qualitative interviews were conducted face to face with landholders (referred to as farmers) (N = 12) and individuals from the economically marginalized community (referred to as marginalized community) (N = 12). The grounded theory approach to data analysis was used and results of the coding method used were displayed by means of superscripts. Results indicate that farmers were aware of broader uses of IAPs although they themselves did not utilise them as extensively as members of the marginalized communities. Invasive alien and problem plants that held value for both land-users were not perceived as being „invasive‟. Invasive alien plants were believed to have detrimental impacts on biodiversity and ecosystems goods and services which support people‟s livelihoods. Alien clearing programmes such as Working for Water (WfW) and LandCare have done much to alleviate the socio-economic burden of unemployment in this marginalized community. Aside from the social development aims set out by WfW (i.e. employment of low-income communities, poverty alleviation and skills training), knock-on social development benefits (e.g. feelings of pride, responsibility and awareness as well as conflict management skills) were also realised by individuals from the marginalized community that were previously employed by the programme. Farmers regarded alien clearing and management as a process that demands excessive time, energy and financial resources. On single occasions it was found that farmers employed methods other than the conventional clearing and management strategies (e.g. livestock that feed on IAPs and giving refuse IAP biomass from clearing and felling to neighbouring poor communities). No clear consensus was reached about regarding alien clearing and management but more support is desired from government. Working for Water relies on private landholders for alien clearing as it is required by law. This study emphasizes that stronger relationships between government and private landholders as well as more substantial incentives to clear IAPs on private land are prerequisites if required outcomes are to be achieved. Educating society at large about the detrimental impacts of IAPs is fundamental. Additionally, informing landholders on effective alien clearing methods and policies and legislation pertaining to it are key activities for the South African government. Finally, clearing and management programmes need to consider the benefits that local land-users obtain from IAPs when prioritising areas for the management of alien vegetation.
AFRIKAANSE OPSOMMING: Uitheemse indringerplante (UIPe) is bekend vir die nadelige gevolge wat hulle vir biodiversiteit en ekosisteem goedere en dienste inhou. ʼn Aansienlike liggaam van navorsing het bygedra tot ons begrip van die impak daarvan op ekologie. In teendeel, die sosio-ekonomiese aspekte van UIPe word egter nie goed verstaan nie. Daarbenewens, evalueringspraktyke het gewoonlik die positiewe en nie-monetêre impakte (voordele en gebruike) wat UIPe vir plaaslike lewensbestaan hou, uitgesluit. Holistiese evaluering word as noodsaaklik beskou vir besluitneming en bestuursraamwerke. ʼn Studie was uitgevoer in Elim op die Suid-Kaapse kus van die Agulhas-vlakte, Suid-Afrika. Die doel was om die verskillende aspekte van UIP impakte op die lewensbestaan van landelike grondgebruikers aan te spreek. Individuele kwalitatiewe onderhoude is van aangesig tot aangesig gevoer met grondeienaars (na wie verwys word as boere) (N = 12) en individue van die ekonomies gemarginaliseerde gemeenskap (na wie verwys word as gemarginaliseerde gemeenskap) (N = 12). Die gegronde teorie metode tot data analise was gebruik en die resultate van die kodering metode is vertoon deur middel van boskrifte. Resultate dui daarop dat boere bewus was van ʼn wyer reeks van gebruike van UIPe alhoewel hulle dit nie so ekstensief benut het soos die lede van die gemarginaliseerde gemeenskappe nie. Uitheemse en probleem plante wat waarde gehou het vir beide landgebruikers,was nie soseer beskou as „indringers‟ nie. Daar was geglo dat UIPe nadelige impakte het op biodiversiteit en ekosisteme goedere en dienste wat mense se lewensbestaan ondersteun. Programme soos Werk vir Water (WvW) en LandCare wat fokus op die uitroeiing van UIPe, het baie gedoen om die sosio-ekonomiese laste as ʼn gevolg van werkloosheid in hierdie gemarginaliseerde gemeenskap te verlig. Benewens die sosiale ontwikkelings doelwitte uiteengesit deur WvW (o.a. indiensneming van lae-inkomste gemeenskappe, armoedeverligting en vaardigheidsopleiding), is daar ook domino-voordele (bv. gevoelens van trots, verantwoordelikheid en bewustheid sowel as konflik bestuursvaardighede) aangaande sosiale ontwikkeling ervaar deur individue van die gemarginaliseerde gemeenskap wat voorheen in diens van die program was. Boere beskou die uitroeiing en bestuur van UIPe as ʼn proses wat oormatige tyd, energie en finansiële hulpbronne vereis. Op enkele geleenthede was dit gevind dat boere gebruik maak van metodes anders as die konvensionele skoonmaak-en bestuurs strategieë (bv. vee wat voed op UIPe en biomassa wat na afloop van skoonmaak aan die naburige arm gemeenskappe gegee word). Geen duidelike konsensus is bereik met betrekking tot die uitroeiing en bestuur van UIP nie, maar meer ondersteuning van die regering word verlang. Werk vir Water maak staat op private grondeienaars vir die uitroeiing van UIPe. Hierdie studie beklemtoon dat sterker verhoudings tussen die regering en private grondeienaars sowel as meer aansienlike aansporings om UIPe op private grond skoon te maak ʼn voorvereiste is as verwagte uitkomste bereik wil word. Opvoeding van die breër gemeenskap oor die nadelige impakte van UIPe is fundamenteel. Om grondeienaars in te lig oor effektiewe UIP verwyderingsmetodes asook beleide en wetgewing met betrekking daartoe, is belangrikste aktiwiteite vir die Suid-Afrikaanse regering. Ten slotte, skoonmaak- en bestuursprogramme moet oorweging skenk aan die voordele wat plaaslike landgebruikers put uit UIPe wanneer daar geprioritiseer word vir gebiede vir die bestuur van indringerplante.
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Theile, H. Lenore. "Invasion of contrasting ecosystems by alien plant species /". [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18380.pdf.

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Zhang, Zhijie [Verfasser]. "Coexistence of alien and native plants / Zhijie Zhang". Konstanz : KOPS Universität Konstanz, 2020. http://d-nb.info/1223371883/34.

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Higgins, Steven Ian. "Predicting rates and patterns of alien plant spread". Doctoral thesis, University of Cape Town, 1998. http://hdl.handle.net/11427/23675.

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The invasion of alien plants into natural ecosystems is a widespread phenomenon that impacts negatively on ecosystem structure and functioning. The invasion and subsequent spread of an alien plant population is equivalent to the processes of colonisation and migration. This implies that the existing toolbox of techniques developed for plant succession research should be useful for predicting plant invasions. Practitioners of invasion biology . have, however, found biological invasions frustratingly difficult to predict. The aim of this thesis was to use succession models to develop a modelling protocol for predicting rates and patterns of alien plant spread. The rationale was that such a model would both improve our understanding of the determinants of invasions and allow us to make predictions on the rates and patterns of alien plant spread. Such predictions are likely to be extremely valuable for the tactical and strategic management of plant invasions. Many modelling approaches could be .. adopted: the need to transcend the gap from general models of plant spread to management models led me to select a spatially explicit simulation modelling approach. The modelling approach is developed by comparing the behaviour of an individual based spatially explicit simulation (SEIBS) model of plant spread to the behaviour of the classic Skellam reaction diffusion model. This process also served to define the model's sensitivity and data requirements. The model's heuristic value is demonstrated by exploring why it is so difficult .to predict which plant will invade which environment. The model also ·provides a useful tool for exploring the role of long-distance dispersal in determining invasion rates. I show that long-distance dispersal is extremely difficult to define statistically, but is a key determinant of invasion rates. The model is validated using independent data on the spatial demography of two invasive species, Acacia cyclops and Pinus pinaster, and independent historical reconstructions of invasions. This validated model was then used to develop a dynamic landscape-extent model. This scaled-up model explores the optimal strategies for clearing alien plants and the ability of different clearing strategies and funding schedules to mitigate the threat that alien plants pose to native species. I conclude that models that are tightly linked to understanding of ecological processes and to field data can be used to rapidly develop predictive models. The development of these models challenges our fundamental ecological understanding and, therefore, emphasises the interplay between data, theory and prediction.
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Emer, Carine. "Multiple aspects of alien species in pollination networks". Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.686826.

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In a rapidly changing world, where many species are declining due to anthropogenic disturbance while others are invading disturbed habitats, understanding how alien species affect ecological processes is crucially important. In this thesis I use ecological networks as a tool to investigate how alien species integrate and affect pollination at the community level. First, I tested whether the invasion of an alien plant (Impatiens glandulifera) affects pollen transfer networks and found no significant change in network structure between invaded and uninvaded habitats. While more alien pollen was recorded on invaded sites only five plant species retained 91% of all balsam pollen on their stigmas. These results point towards the robustness of pollination networks to plant invasion. Second, I investigated intraspecific variability and specialization in pollen transport and pollen transfer networks; strong intraspecific variation was found for both plants and pollinators along with higher specialization found in pollen transport networks. And finally, I asked whether a species role in network structure differs between its native and alien ranges and whether the former can be used to predict the latter; no significant difference in species role between ranges was detected, and degree and closeness were highly predictable from native to alien habitat. These results suggest species roles conservatism in pollination networks, whereby a species role in a network is similar whether it occurs in the native or in the alien range of its distribution. I conclude that a holistic approach encompassing different spatial, temporal and biological scales is needed if the aim is to understand how alien species interact and affect pollination. I also highlight ecological networks as a powerful tool to understand anthropogenic effects at the community level and suggest that merging the expertise from different disciplines is needed if we are to truly understand the invasion process.
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Koleth, Maria Yesudasan. "Alien Game: The impossible ethics of development tourism". Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/15354.

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Development tourism provides something to believe in even through the incredible excesses and depletions of neoliberal reform and the extension of coloniality. It takes first world tourists to various projects around the world so that they can assist with development efforts through volunteering and immersion. Such popular action has been widely criticised in the existing literature, however, this ethnography of development tourism contributes to a more productive conceptualisation of the ‘popular’ as a dynamic intervention into the field of development ethics. I contextualise development tourism within emerging spaces of popular development defined by diverse, inexpert and privileged forms of agency, populist discourses and uneven ethical practices. The diversity of my participants’ practices of belief, in particular, challenges the liberal consensus over the capabilities framework and the end of poverty in development ethics. I argue that development tourists do creative ethical work by building aporetic relations of belief to futures and forms of contribution to development work that are so incommensurable to the contemporary consensus as to be impossible. Drawing on post-colonial re-readings of Jacques Derrida’s work on the impossible, I understand belief as a simultaneously immaterial and material relation to the impossible figures of the contingent limit points of development ethics. I explore the way in which my participants relate to the limit-points of giving enough, community, a post-development era, a racialised poverty and a better future as figures of the impossible. I use literatures on development ethics, faith, post-development, planetarity, future-making, the social life of things and the affective presence of pain to illuminate the emergence of belief as a destabilising and excessive experience of the impossible. Belief in these impossible limits emerges in ambivalent materialisations between proliferating first worlds and the ‘Third World’. Far from guaranteeing equitable or positive change, relations of belief transform the boundaries and possibilities of the development industry.
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29

Saul, Amelia Mozelle. "Exploring the “density-benefit” relationships of alien species". Thesis, The University of Sydney, 2021. https://hdl.handle.net/2123/25806.

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The disastrous impacts of invasive alien species are well-documented. However, there is growing evidence that some alien species can also have positive effects in their new environments, adding complexity to their management. Classic density-damage relationships are used to determine cost effective densities at which to control alien populations and limit their adverse effects. In this thesis I proposed that the ecological benefits of alien species are also related to population density, and I hypothesised the different types of relationships that may exist. I then investigated the "density-benefit" relationships of three common alien species through a series of manipulative field experiments. Firstly, I examined the effect of population density on the pollination behaviour of alien black rats, Rattus rattus, that provide a pollination function for an Australian native plant. I found black rats at high densities behave in a way that may reduce their pollinator efficacy. I next investigated the effect of density upon an alien plant, Lantana camara, providing refuge for small native reptiles. I found that the abundance of reptiles was related to L. camara density in a U-shape, showing a benefit at high densities only. Then I conducted a simulation experiment to compare the digging activities of native marsupials and alien European rabbits (Oryctolagus cuniculus) at different densities. Digging density was significantly related to the germination and survival of seedlings. However, I detected a difference in the quality of the ecological function provided by these analogous alien and native species. Together, these results suggest that “density-benefit” relationships need to be integrated into the management of alien species densities. This work will advance the current understanding of alien species ecology, guide the management of alien species with complex impacts and ensure that significant ecological benefits provided by alien species are not lost unnecessarily.
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CHATZIDIMITRIOU, EVANGELIA. "Alien Invasive Species in Europe: Three Case Studies". Doctoral thesis, Università degli studi di Padova, 2016. http://hdl.handle.net/11577/3427137.

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The incidental introduction of alien phytophagous insects and mites has become quite a common event in the world owing to intensive commercial exchanges of plants and goods and ever-increasing tourist traffic. There is evidence that this phenomenon is increasing, in spite of the control measures of the EU phytosanitary system in order to minimize unintentional introductions. The introduction of an alien species in a new ecosystem and the interaction between an alien species and the autochthonous species usually has many disadvantages. The alien species can dominate the invaded ecosystems and eventually become an invasive species due also to the absence or paucity of natural enemies. These invasions can affect the native species that become less common or threatened with extinction. Apart from the environmental impacts alien species are known for their economic and health impacts. In this study were investigated mostly 3 recently introduced alien species in Italy, namely Tuberocephalus (Trichosiphoniella) tianmushanensis Zang (Hemiptera Aphididae), Cydalima perspectalis (=Glyphodes) (Walker, 1859) (Lepidoptera Crambideae), the box caterpillar and Phenacoccus defectus Ferris (Rhynchota Pseudococcidae). The first chapter is a background of invasive ecology and presents with graphs the high number of alien species introduced in Europe the last years.. The second chapter is dealing with Tuberocephalus (Trichosiphoniella) tianmushanensis Zang, an Asiatic heteroecious species so far not recorded in Italy. This species was collected in the University Botanical Garden of Padova in spring 2012. On May 30, 2012 reddish-pink galls, with aphids inside, were observed on the leaves of two Prunus subhirtella cv. pendula trees (Rosaceae) (Weeping Higan Cherry), about 40 years old. Once mounted on slides the aphids were identified as Tuberocephalus (Trichosiphoniella) tianmushanensis Zang. The purposes of this study were to collect data on species distribution over the territory, by monitoring ornamental cherry trees in the Veneto region, to observe the phenology and biology of the Asiatic aphid, to study the life-cycle in screen houses and outdoors, to verify if its secondary host plant was an Artemisia sp., as reported in bibliography. Another aspect of the work was to provide an overview of the species belonging to the genus Tuberocephalus so far described, by consulting the available literature. It was made an effort to gather all the currently available information for each species, its distribution and information on their biology mainly regarding the first and secondary host plants. Results showed that Tuberocephalus (T.) tianmushanensis, is now considered acclimatized in our environment. The aphid is closely related to the presence of its primary host Prunus subhirtella v. pendula with pink flowers. The aphid can carry on two generations on Prunus and can induce two types of leaf galls. The gall A is induced by the fundatrix, while the gall B is induced by the fundatrigeniae. The trial of colonization on Artemisia vulgaris, failed for the second successive year so possibly Artemisia vulgaris is not the secondary host plant of the aphid, as reported in literature. The third chapter concers Cydalima perspectalis (Lepidoptera, Crambiidae) (Walker, 1859), an asiatic pest of Buxus. It was reported for the first time in Europe in Germany in 2007. In Italy it was detected in 2011, in Lombardy, Como province. In a very short time it invaded the other northern regions and was recorded in Veneto in 2012. The larvae feed on leaves and shoots of the box trees and the infestations lead to defoliation of the plants. The objective of this study was to investigate the phenology of C. perspectalis. More precisely we examined the biological cycle of life, the number of molts and the overwintering stage. In addition host plants were monitored by regular samplings, from late winter to late fall to collect data on species distribution over the territory. The life-cycle was studied in screen houses and in the field, to investigate the role of potential predators and parasitoids. Additionally experiments were conducted with pheromones traps with the purpose of checking, monitoring and collecting data on species distribution over the territory, finding any possible differences based on climate, checking the potential differences between types of traps. According to the results of 2014 and 2015 in the Veneto Region C. perspectalis develops three generations / year. In 2014 the overwintering larvae started their activity early in February until mid-April while in 2015 one month later until end of April probably due to different climate conditions between these years. C. perspectalis overwinters in a silk cocoon in-between the leaves as a larva of 2nd instar and the number of larval instar is 5. The number of captures from the sex pheromones traps was low. No differences were observed between the two types of pheromones. C. perspectalis has spread quickly in our environment proving that it has acclimatized. So far, it seems there has been no adaptation by indigenous natural enemies (parasitoids) to C. persectalis. The next chapter is focued on the difficulty to separate the Phenacoccus solani Ferris and P. defectus Ferris (Hemiptera: Pseudococcidae). They are morphologically similar and the microscopic morphological characters of the adult female alone are not enough. In order to resolve their identity, a canonical variates morphological analysis of 199 specimens from different geographical origins and host plants and a molecular analysis of the CO1 and 28S genes were performed. The morphological analysis supported synonymy of the two species, as although the type specimens of the "species" are widely separated from each other in the canonical variates plot, they are all part of a continuous range of variation. The molecular analysis showed that P. solani and P. defectus are grouped in the same clade. On the basis of the morphological and molecular analyses, P. defectus is synonymized under the senior name P. solani, syn. n. Finally a zoogeographic analysis of the Greek scale insects fauna (Hemiptera, Coccoidea) was carried out with the aim to highlight how many alien scale insects species are so far present in the Greek territory. According to the last data, the scale insect fauna of whole Greek territory comprehends 207 species; a total of 187 species are recorded in mainland Greece and minor islands, whereas only 87 scale species are known so far in the island of Crete. The most numerous families are the Diaspididae, with 86 species in total, followed by Coccidae, with 35 species and by Pseudococcidae, with 34 species. The results of a first zoogeographical analysis of scale insect fauna of mainland Greece and the island of Crete is also presented. Five scale species, respectively four in mainland Greece and one in Crete, are considered as endemic. This analysis demonstrated that alien scale insects, introduced and acclimatized a long time ago or recent invaders, make up 30% of the Greek scale insects fauna.
Tra le specie di Phenacoccus neartiche, P. defectus Ferris, P. solani Ferris è P. solenopsis Tinsley condividono l’insolito carattere morfologico dell’assenza di pori pentaoculari è sono morfologicamente simili da rendere difficile l’ identificazione. Il problema della loro identificazione è stato evidenziato da diversi autori (McKenzie, 1967; Williams & Granara de Willink, 1992; Culik & Gullan, 2005; Pellizzari & Porcelli, 2013), benché sia generalmente riconosciuto che P. solenopsis possieda un maggior numero di pori multiloculari e un circulus di maggiori dimensioni rispetto alle altre due specie; inoltre quest’ultima è una specie bisessuale mentre le altre due si riproducono per partenogenesi. Le tre specie di cocciniglie condividono diverse piante ospite. In accordo con Hodgson et al. (2008) ci sono elementi che supportano l’ipotesi che si tratti di varianti di una singola specie. Per definire meglio il loro status tassonomico, abbiamo amplificato mediante PCR e sequenziato il frammento di DNA ‘barcode’ di P. solani, P. solenopsis, e P. defectus.
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31

Cavedo, Keith. "Alien Encounters and the Alien/Human Dichotomy in Stanley Kubrick‘s 2001: A Space Odyssey and Andrei Tarkovsky‘s Solaris". Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1593.

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The alien encounter has long been a defining and popular subject of science fiction cinema. However, Stanley Kubrick's 2001: A Space Odyssey (1968) and Andrei Tarkovsky's Solaris (1972) are interrogative, complex, and distinct artistic accomplishments that stand apart from and above the conventional science fiction film. 2001 and Solaris not only represent but complicate the alien/human dichotomy; in the end, they destabilize the dichotomy and even suggest a radical synthesis of the dichotomous elements. 2001 and Solaris further emphasize epistemological and specifically anthropocentric limitations when it comes to understanding the alien or attempting to make sense of the alien encounter. Chapter 1 introduces the alien/human dichotomy in two representative science fiction films of the period, This Island Earth (1955) and Planet of Storms (1962). Chapter 1 provides some contextual and contrapuntal basis for the originality of 2001 and Solaris. Chapter 2 reviews critical literature directly and indirectly addressing alien and human identity, interpretations of symbolic forms such as the monolith in 2001 and "guests" in Solaris, and both films' ambiguous, multivalent endings. Chapter 3 (on 2001) and Chapter 4 (on Solaris) examine the alien/human dichotomy in specific scenes where an alien, non-human presence appears to be present or where an alien encounter significantly occurs. The two chapters analyze techniques such as the significance of the establishing shot and other shots or cinematographic effects, settings, point of view, and non-diegetic music. By way of conclusion, Chapter 5 compares 2001 and Solaris and makes the argument for the differences between-and departures from-the two film masterpieces and conventional science fiction films. Chapter 5 ends with further considerations of the argument and a broadening of the context. This dissertation should be of interest not only to science fiction scholarship in general but to film studies in particular. It aims to provide a sophisticated reading of 2001: A Space Odyssey and Solaris supported by recent criticism in an effort to join in the ongoing scholarly discussion and critical legitimatization of science fiction cinema.
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32

Ballard, Meg. "Insect populations on early successional native and alien plants". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 50 p, 2006. http://proquest.umi.com/pqdweb?did=1203553531&sid=1&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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33

西川, 輝昭, Teruaki Nishikawa, D. D. Bishop John y Dorothea Sommerfeldt A. "Occurrence of the alien ascidian Perophora japonica at Plymouth". Cambridge University Press, 2000. http://hdl.handle.net/2237/10552.

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34

Casale-Katzman, Emma-Alexia. "Enemy Alien : A novel and commentary, vol 1: commentary". Thesis, University of Essex, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510513.

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35

Pearl, Monica B. "Alien tears : mourning, melancholia, and identity in AIDS literature". Thesis, University of Warwick, 1999. http://wrap.warwick.ac.uk/4310/.

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This thesis examines the literary response to the AIDS crisis. It concentrates on literature produced between 1988 and 1995, published in English, and available in Britain and the United States. The AIDS texts investigated here are representative of other AIDS literature produced during this time period in the way that they both enact and construct the identities of those affected by AIDS. Mourning and melancholia are the operative responses revealed in the literature, and revealed as the formative components of changing identities in response to AIDS and its manifestations. The thesis is structured in six chapters: a theoretical introductory chapter that proposes mourning and loss as pre-existing concerns in gay men's literature, followed by a chapter addressing gay AIDS fiction and its narrative response to mourning. The next two chapters examine hybrid texts, that is, AIDS texts that do not conform to a conventional narrative form, and that are connected more firmly to a queer sensibility than to a gay identity. These texts, the thesis claims, are engaged with the processes (and resistances) of melancholia rather than with the work of mourning. The subsequent chapter addresses fictions of caretaking and witnessing, that is, novels written from the point of view of one who is caring for an other ill with AIDS. These are identified as more mainstream texts as they involve representations that are not connected to declared sexual identities and therefore mean to address a wider audience and to work out a more public discourse of grief around AIDS. In conclusion, the thesis suggests that although AIDS literature is involved in an effort to resist loss through narrative form, in fact it is the literature that in some instrumental ways makes the work of mourning and melancholia in response to AIDS productive rather than debilitating.
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36

Lopezaraiza, Mikel Martha Elena. "The impact of alien species on native pollination systems". Thesis, University of Bristol, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427906.

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37

Evans, Thomas. "Quantifying and categorising the environmental impacts of alien birds". Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10060518/.

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We are faced with a rising tide of alien species introductions across the globe. Some of these species can have significant impacts on native biodiversity. Being able to identify those species that are likely to cause the most damage when introduced to new environments is crucial if we are to minimise the broad range of impacts that they may have. A protocol has recently been developed to quantify and categorise the environmental impacts of alien species: the Environmental Impact Classification for Alien Taxa (EICAT). In Chapter 2, I use EICAT to quantify and categorise the impacts of alien species for an entire taxonomic class (birds). In so doing, I generate the first, directly comparable global dataset on their environmental impacts. The assessment reveals that most alien birds have relatively minor impacts, but that some have population-level impacts that result in native species extirpations and extinctions. The EICAT assessment provides useful information on the ways in which alien birds can adversely affect the environment, and the types of species that have the most severe impacts. It also reveals that we do not have any data on the environmental impacts of over 70% of alien bird species globally: these species are classified as Data Deficient (DD) under EICAT. I use the data generated by the EICAT assessment to answer a number of outstanding questions regarding the environmental impacts of alien birds. In Chapter 3, I examine the factors that influence whether we have impact data for alien birds. I show that many species may be DD because they have minor impacts that do not attract scientific research, but that some species may be DD for reasons unrelated to the severity of their impacts. In Chapter 4, I identify the traits of alien birds that influence the severity of their environmental impacts, finding that widely distributed, generalist birds tend to have the most severe impacts. In Chapter 5, I identify the drivers of spatial variation in the severity of alien bird impacts, finding that factors relating to the duration and frequency of alien bird invasions are key in determining whether the impacts sustained by a region will be damaging. I also produce the first global maps displaying the impacts generated by alien species from an entire taxonomic class. These maps, and the data underpinning them, can be used to identify regions of the world susceptible to the impacts of alien birds. They may therefore assist in directing management interventions to regions where they are most needed.
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GOMES, Diego de Azevedo. "Modelling and mitigation of alien crosstalk for DSL systems". Universidade Federal do Pará, 2017. http://repositorio.ufpa.br/jspui/handle/2011/10090.

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CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
G.fast é o padrão mais recente do ITU-T para transmissões DSL, o qual e destinado para topologias do cobre de curtas distâncias e adota uma largura de banda de 106 MHz, que pode ser extendida at é 212 MHz. Em muitas situações os sistemas G.fast serão compostos ou coexistirão com linhas não-coordenadas (o linhas alien), as quais são fonte de forte crosstalk, pois estas linhas não fazem parte do grupo vetorizado. Este documento apresenta uma formula ção que explica o desempenho de m étodos de mitiga ção de alien crosstalk de acordo com o n úmero de linhas alien no ambiente, o mecanismo que defi ne a correla ção desta interferência e um m étodo de mitiga ção de alien crosstalk para transmissões DSL na dire ção de downstream afetadas por m últiplos interferentes, chamado AMMIS. Os resultados das simula c~oes mostram que os m étodos de mitiga c~ao de alien crosstalk encontrados na literatura podem de fato melhorar o desempenho de sistemas G.fast, mas apenas em condi ções específi cas. N os contrastamos estas situa c~oes e apresentamos diretrizes acerca da viabilidade destas t écnicas de mitigação em cen ários com n úmeros distintos de linhas alien. Adicionalmente, o AMMIS apresenta resultados promissores em rela c~ao a taxa de dados quando comparado com os m etodos encontrados na literatura em cen arios com grande quantidade de interferentes, com a vantagem adicional de ainda possibilitar economia de energia. Como suporte para as simula ções, tamb ém apresentamos um conjunto de medi ções de alien crosstalk.
G.fast is the most recent ITU-T standard for DSL transmission, which targets copper topologies with short distances and adopts a bandwidth of 106 MHz extensible to 212 MHz. In several situations, G.fast systems will be composed by or coexist with uncoordinated (or alien) lines, which are sources of strong crosstalk, because these lines are not part of the vectored group. This document presents a formulation to explain the performance of the alien crosstalk mitigation methods according to the number of alien lines in a certain environment, the mechanism that de nes the interference correlation of it and an alien crosstalk mitigation method for downstream DSL transmission impaired by multiple interferers called AMMIS. Simulation results show that alien crosstalk mitigation methods found in the literature can indeed improve the performance of G.fast systems, but only under speci c conditions. We have contrasted these situations and we provide guidelines about the feasibility of the crosstalk mitigation techniques in scenarios with distinct number of alien lines. Additionally, the AMMIS shows promising results in relation to the bit rate when compared with literature methods in scenarios with a large number of interferers, with the additional advantage of allows power savings. As support for the simulations, we also present a set of alien crosstalk measurements.
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39

Ray, Michael George Ian. "Alien courtiers of thirteenth-century England and their assimilation". Thesis, University of London, 2003. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.658708.

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40

Robinson, Tamara Bridgett. "Marine alien species of South Africa : threats and opportunities". Doctoral thesis, University of Cape Town, 2005. http://hdl.handle.net/11427/6705.

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Until recently, marine bioinvasions have received little attention in South Africa, and the status of intertidal marine aliens was last assessed in 1990. I thus investigated the present distribution and status of three intertidal alien species (Mytilus galloprovineialis, Care in us maenas and Careinus aestuarii) and documented the presence and status of a previously unknown invasive, the Japanese oyster, Crassostrea gigas. M galloprovincialis was recorded along the entire west coast of South Africa, with populations extending up to central Namibia, and along the south coast of South Africa to 40 km west of East London. Along South African shores a total stock of 35 403.7 tons (± 7 241.4 SE) was recorded, with the vast majority of the stock occurring on the west coast (31 054.5 tons ± 6 274.1 SE). C. maenas supports a substantial population of 133 568 individuals (95 % confidence range == 97 694 - 166 862) in Table Bay Harbour which appears to be acting as in invasion incubator for surrounding areas. A new population of 9 180 individuals (95 % confidence range 5 870 - 12 003) was recorded in Hout Bay Harbour. This represents a range extension along the Cape Peninsula. The low intertidal abundance of this crab between these localities is thought to reflect the inability of C. maenas to inhabit exposed habitats. C. aestuarii was not recorded during this study despite previous documentation of its presence. In 2003, naturalised populations of C. gigas were documented in the low shore zone of the Breede, Goukou and Knysna Estuaries, but not on the open coast. This may again be indicative of the limiting effect of wave action on species alien to South African shores. As such, the presently undetermined impact of this species may well be focused on estuarine habitats. To quantify the threat posed to intertidal communities by M galloprovincialis, changes in community structure on the rocky shore of Marcus Island and the sandy shore of Langebaan Lagoon were measured. In both habitats, the invasion significantly altered community composition. On Marcus Island the effects were focused within the mid-to-low intertidal zones, where habitat complexity was enhanced and patchiness was decreased, resulting in dramatic changes in invertebrate density, species number, richness and diversity. On sandy shores, M galloprovincialis beds changed available habitat structure, resulting in a concurrent invasion by indigenous rocky shore species. In the sediment below the mussel beds, soft-sediment species were excluded due to anoxia. Following a die-off of the mussel beds the rocky shore species disappeared, but were not replaced by sandy shore organisms as the sediment remained uninhabitable. The subsequent removal of the dead mussel shells appears to have recovered, but community composition is still to return to the preinvasion state. In order to consider the biological viability of a fishery for A1. galloprovincialis in the Northern Cape, a harvesting project operated by two impoverished coastal communities was initiated. Harvesting took place on a rotational basis and twelve sites, nested within four harvesting locations, were each exposed to spectrum of harvesting intensities (F=O, F=30%, F=60% and F=90%). A dynamic biomass-based fisheries model predicted monthly Maximum sustainable yield (MSY) estimates of 1 560 kg per 100 m of shore in March-April and September-October, but two orders of magnitude less (15 kg) during the remaining months. These peaks correspond to spawning periods of this mussel along the South African west coast. Experimental manipulations revealed high recruit densities recorded at low harvesting intensities (2 000 20 000 per 0.01 m exceeding levels required for population maintenance. However, if adult mussel beds are eliminated or significantly reduced (which occurred at F=30% or above), recruitment may limit stock replenishment. Indirect effects on non-target species were also considered. Intertidal communities changed dramatically in response to harvesting, with increased algal dominance and shifts in the distribution of grazers between primary- and secondary-substrates. Community composition did not return to the pre-harvest state after four months of no harvesting, even in areas which were only harvested at an intensity of F=30%. Northern Cape intertidal communities are thus considered to have low resilience and elasticity in response to harvesting of A1. galloprovincialis. It is thus recommended that a harvesting intensity of between 10% and 30% be employed if A1. galloprovincialis stocks in the Northern Cape are to be harvested on a commercial basis. This would protect stock replenishment and minimise effects on intertidal communities. In addition, harvesting should be focused within the two spawning seasons spanning peak MSY estimates so as to maximise yield and aid community recovery between harvests. If implemented, this would represent the first instance in South Africa of a marine invasive species being utilised in a way that employs dynamic fisheries management to achieve socioeconomic goals, while taking into account the effects on other elements of the biotic community.
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41

Lee, Feng-Yuh. "Martian language : an alien language or an international language? /". Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1467899081&sid=25&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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42

King, Gary Andrew. "The alien presence : palaeoentomological approaches to trade and migration". Thesis, University of York, 2009. http://etheses.whiterose.ac.uk/887/.

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This thesis addresses the potential of palaeoentomological remains to stand as evidence of past trade and culture contact. Three methodological tools are used to evaluate the effectiveness of insect subfossils as palaeoeconomic indicators: palaeoecology, biogeography, and isotopic analysis. Underpinning each of the methodological approaches is the premise that specific insect fauna are notably stenotopic in their distributional range. By superimposing the physiological and ecological habits of modern species over the archaeological record, they may effectively serve as analogues to interpret palaeoentomological evidence. On that basis, the archaeological presence of stenotopic insects may reliably be employed as indicators of their associated habitats. Furthermore, the examination of the archaeological remains of the specific monophagous or oligophagous species that are known to feed on human exploitable resources may provide direct or indirect evidence towards the presence of those commodities. For example, Sitophilus granarius may stand as an indication of the presence of stored cereal grains. In each of the methodological approaches, the palaeoentomological remains proved promising as a tool for suggesting probable socio-economic activity. However, the approaches differed in the precision and confidence of their results. The palaeoecological approach provided the most tentative assertions; where as the isotopic method allowed for formulation of the most scientifically-grounded conclusions. In addition to the three applied methodologies, the thesis explored the potential for palaeoentomological remains to yield assayable genetic sequences. Ancient DNA was recovered from preserved Roman and medieval specimens. If aDNA preservation is widespread in palaeoentomological remains, a phylogeographic method is conceivable as a means for assessing past trade and migration.
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43

Van, Wilgen Nicola Jane. "Alien invaders and reptile traders : risk assessment and modelling of trends, vectors and traits influencing introduction and establishment of alien reptiles and amphibians". Thesis, Stellenbosch : Stellenbosch University, 2010. http://hdl.handle.net/10019.1/5468.

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Thesis (PhD)--Stellenbosch University, 2010.
ENGLISH ABSTRACT: Biological invasions are a growing threat to biodiversity, trade and agriculture in South Africa. Though alien reptiles and amphibians (herpetofauna) are not currently a major issue, escalating problems worldwide and increased trade in South Africa suggest a possible increase in future problems. In this thesis I explore practical measures for risk assessment implementable under national legislation. I began by documenting record-keeping and legislative differences between provinces in South Africa. This revealed some serious deficiencies, complicating attempts to compile accurate inventories and discern import trends. International trade data, however, revealed an exponential increase in the number of imports to South Africa over the last 30 years. Characterising the abundance of species in this trade is important as species introduced in large numbers pose a higher establishment risk. In South Africa, I found a tendency for venomous and expensive species to be traded in low numbers, whereas species that are easy to breed and handle, or that are colourful or patterned are traded in higher numbers. Unlike South Africa, California and Florida have had a large number of well-documented herpetofaunal introductions. These introductions were used to verify the role of several key predictors in species establishment. I first evaluated the role of each variable separately. I examined different approaches for bioclimatic modelling, the predictive power of different sources of distribution data, and methods of assigning a climate-match score. I also present the first test of Darwin’s naturalization hypothesis for land vertebrates using two new phylogenies inferred for native and introduced reptiles in California and Florida. I then used boosted regression trees (BRT) to infer the relative contribution of each factor to species establishment success. Results from the BRTs were incorporated into a user-friendly spreadsheet model for use by assessors inexperienced in complex modelling techniques. Introduction effort was found to be the strongest contributor to establishment success. Furthermore, species with short juvenile periods were more likely to establish than species that started breeding later, as were species with more distant relatives in regional biotas. Average climate match and life form were also important. Of the herpetofaunal groups, frogs and lizards were most likely to establish, while snakes and turtles established at much lower rates, though analysis of all recorded herpetofaunal introductions shows slightly different patterns. Predictions made by the BRT model to independent data were relatively poor, though this is unlikely to be unique to this study and can be partially explained by missing data. Though numerous uncertainties remain in this field, many can be lessened by applying case by case rules rather than generalising across all herpetofaunal groups. The purpose for import and potential trade volume of a species will influence the threat it poses. Considering this in conjunction with a species’ environmental tolerances and previous success of species with similar life histories, should provide a reasonable and defendable estimate of establishment risk. Finally, a brief summary of the potential impacts of introduced alien herpetofauna is provided in the thesis.
AFRIKAANSE OPSOMMING: Indringer spesies hou ‘n al groter bedreiging in vir die biodiversiteit, handel en landbou van Suid- Afrika. Alhoewel uitheemse reptiele en amfibieërs (herpetofauna) tans nie ‘n groot bedreiging in Suid-Afrika is nie, dui groeiende probleme wêreldwyd asook 'n toename in plaaslike handel op moontlike toekomstige probleme. In hierdie tesis, ondersoek ek praktiese metodes vir risikobepaling wat onder nasionale wetgewing toegepas kan word. Ek begin deur die verskille in stoor van rekords en wetgewing tussen provinsies te dokumenteer. Hierdie proses het ernstige tekortkominge uitgewys, wat pogings om akkurate inventarisse saam te stel en invoertendense te bepaal, bemoeilik. Internasionale handelsdata het egter getoon dat daar ‘n eksponensiële toename in die hoeveelheid invoere na Suid-Afrika oor die laaste 30 jaar was. Die hoeveelheid spesies in hierdie handel is belangrik omdat spesies wat in groot hoeveelhede ingevoer word, ‘n hoër vestigingsrisiko het. In Suid-Afrika is ‘n tendens gevind vir handel in giftige en duur spesies teen lae hoeveelhede, terwyl spesies wat maklik teel, maklik hanteer kan word en kleurvol is of mooi patrone het, in groter hoeveelhede mee handel gedryf word. Kalifornië and Florida, in teenstelling met Suid-Afrika, het ‘n hoë aantal goed-gedokumenteerde gevalle van herpetofauna wat in die natuur vrygestel is. Hierdie introduksies was gebruik om die rol van verskeie belangrike faktore in die vestiging van populasies te bepaal. Eerstens het ek die rol van elke faktor apart ondersoek. Ek het verskillende benaderinge vir bioklimatiese model-bou ondersoek, die akuraatheid van verskillende bronne van distribusiedata getoets en drie metodes om ‘n “climate match score” te bereken, voorgestel. Ek bied ook die eerste toets van Darwin se naturalisasie-hipotese vir landwerveldiere aan, deur gebruik te maak van twee nuwe filogenieë wat ek gebou het vir inheemse en ingevoerde reptiele in Kalifornië en Florida. Ek het verder gebruik gemaak van “boosted regression trees” (BRT) om die relatiewe bydrae van elke faktor tot die vestigings-potensiaal van spesies te bepaal. Resultate van hierdie BRTs was ingekorporeerd in ‘n gebruikersvriendelike ontledingstaat wat deur bestuurders, onervare in komplekse modelboutegnieke, gebruik kan word. Invoer-hoeveelheid was die faktor wat die sterktste bygedra het tot suksesvolle vestiging. Verder is spesies met kort jeugperiodes en dié met verlangse familie in streeks-biotas, meer geskik om suksesvol te vestig. Gemiddelde klimaatooreenstemming en lewensvorm was ook belangrik. Paddas en akkedisse was die mees waarskynlikste van die herpetofauna groepe om populasies te vestig, terwyl slange en skilpaaie teen laer tempo’s populasies gevestig het, alhoewel analise van alle gedokumenteerde gevalle van herpetofauna-invoerings wêreldwyd effens verskillende tendense toon. Voorspellings wat deur die BRT-model vir onafhangklike data gemaak is was redelik swak, alhoewel hierdie resultaat onwaarskynlik nie uniek aan die studie is nie, en word gedeeltelik verduidelik deur die gebrek aan data. Alhoewel talle onsekerhede steeds bestaan, kan dié verminder word deur geval-tot-geval reëls toe te pas eerder as om vir herpetofauna as ‘n groep te veralgemeen. Die doel van invoer en potensiële handel-volumes van ‘n spesie, sal die bedreiging wat die spesie toon, bepaal. Hierdie faktore moet saam met omgewingstoleransie en voorafgaande sukses van spesies met soortgelyke lewenswyses oorweeg word, om ‘n aanvaarbare en verdedigbare beraming van vestigingsrisiko te gee. Laastens, word ‘n kort opsomming van die effekte wat uitheemse herpetofauna mag hê, verskaf.
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44

Nordgren, Johannes. "An Alien discussion : Using the film Alien to highlight and discuss sexual violence and gender roles in the Swedish upper secondary EFL classroom". Thesis, Linnéuniversitetet, Institutionen för språk (SPR), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-101923.

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The essay attempts to analys the film Alien directed by Ridley Scott and released in 1979 to see if the film’s themes and iconography can be interpretedas metaphors forsexual violence and gender norms. investigates if the film can be used in a Swedish upper secondary EFL classroom as a basis for discussing the societal problems of sexual violence and oppressive gender norms. Methods for film analysis by Barker and Austin is applied along with the gender theories of Moi and Connell among others.
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45

Andreu, Ureta Jara. "Management of alien plants in Spain: from prevention to restoration". Doctoral thesis, Universitat Autònoma de Barcelona, 2012. http://hdl.handle.net/10803/83943.

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Degut als impactes ecològics i socioeconòmics causats per les invasions biològiques, la seva gestió s’ha convertit en un repte important i una prioritat pels gestors mediambientals. A Espanya, la informació sobre la gestió de les plantes exòtiques està força dispersa i, en general, no hi ha gaire flux d’informació entre el món acadèmic i el món de la gestió. Per aquests motius, el principal objectiu d’aquesta tesi ha estat aprofundir en les mesures de gestió de plantes exòtiques a Espanya, identificant les seves principals limitacions. Conèixer aquestes limitacions ens ha dut a plantejar‐nos els següents objectius específics: 1) Identificar les principals plantes exòtiques problemàtiques a Espanya i avaluar els criteris utilitzats a l’hora de prioritzar la seva gestió; 2) Identificar i classificar les espècies potencialment invasores per Espanya; 3) A nivell global, quantificar mitjançant un metaanalisi els impactes de les plantes invasores i les conseqüències de la seva eliminació en les comunitats natives; i 4) Com a cas d’estudi, avaluar l’eficàcia de l’eliminació manual de Carpobrotus sp. a la costa d’Andalusia, i la recuperació de la vegetació nativa. Tenint en compte que les mesures de control i eradicació d’espècies exòtiques són extremadament costoses és molt important prevenir l’entrada i l’establiment d’espècies potencialment invasores, així com garantir l'eficàcia de les mesures de gestió aplicades. Aquesta tesi omple una mica el buit d’informació entre el món acadèmic i el de la gestió, proporcionant informació als gestors ambientals per tal de millorar l’eficàcia de les mesures de gestió aplicades. Les principals conclusions són: I. Les invasions biològiques són considerades pels gestors ambientals un problema de prioritat mitjana i un total de 109 plantes exòtiques problemàtiques han estat gestionades. II. La gestió de les plantes exòtiques s'ha centrat principalment en l'aplicació de mesures de control mecànic o químic a escala local i dissenyades, normalment, amb objectius a curt termini. Existeix, per tant, una manca de mesures de prevenció, mesures de seguiment a llarg termini i de pautes per a la priorització de la gestió d’espècies exòtiques. III. Mitjançant l'ús d'esquemes d'avaluació de riscos, s'ha elaborat una llista preliminar de 80 espècies potencialment invasores per Espanya, sent la jardineria la principal via d’entrada d’aquestes espècies. Les espècies amb les puntuacions més altes han resultat ser principalment plantes aquàtiques, i s’hauria de prohibir la seva entrada i comerç. Chromolaena odorata (Asteraceae) és l’espècie amb les puntuacions més altes i, per tant, podria ser considerada l'espècie amb major risc d'esdevenir invasora a Espanya, en cas que s'introduís al medi natural. IV. Aquesta tesi presenta un marc conceptual que compara llocs envaïts, llocs de referència no envaïts i llocs on una determinada espècie invasora ha estat eliminada. Aquestes comparacions permeten quantificar el impacte de l’espècie invasora en qüestió i supervisar la recuperació de les plantes natives després de la seva eliminació. En estudis científics, aquestes comparacions no solen ser utilitzades de manera combinada, i els llocs de referència són poc emprats per avaluar la recuperació d'espècies natives després de l'eliminació. Creiem que l’ús d’aquest enfocament comparatiu hauria de ser més emprat per supervisar l’eficàcia de les mesures de gestió, perquè a més, permet avaluar els possibles efectes secundaris de les tècniques d'eliminació, així com la necessitat de dur a terme mesures de restauració específiques a posteriori. V. La revisió bibliogràfica global demostra que les plantes invasores són responsables d'una disminució local en la riquesa i abundància d'espècies natives. Això, ha estat corroborat pel cas d’estudi sobre l’eliminació de Carpobrotus, on aquesta espècie també redueix significativament la riquesa d'espècies natives en les comunitats que envaeix. VI. En general, després de l'eliminació de les plantes invasores, la vegetació nativa té el potencial de recuperar‐se fins arribar als nivells desitjats previs a la invasió.
Now that the increasing impacts and costs of invasive species are being recognized, management of alien species has become an important challenge and a high priority for environmental managers. However, in Spain, management information on alien plants is quite scattered and, in general, there is a lack of communication between managers and scientists. The general aim of this thesis has been to investigate the management measures on alien plants carried out in Spain and to identify the main limitations of these measures. Once knowing these limitations the following specific objectives have been addressed: 1) To identify the most problematic invasive plant species in Spain and to assess the main criteria used to prioritize their management; 2) To identify and rank potentially invasive species in Spain, not present in the wild yet; 3) To quantify at a global scale, by means of a meta‐analysis, the impacts of invasive plants as well as the consequences of their removal over native communities, and 4) To evaluate, as a case study, the efficacy of the manual removal of Carpobrotus sp. in the coast of Andalucía, and the recovery of the native vegetation after the alien plant removal. Given that management measures are extremely costly in terms of human, technical and economic resources, it is really important to prevent potential invasive species as well as to guarantee management effectiveness in those cases where prevention is no longer a solution. This thesis have provided clear direction for bridging the current gap between the availability in information on alien plant species and the need for environmental managers to successfully prevent and control invasive species. Specifically, the main conclusions are: 1) Biological invasions are considered by Spanish environmental managers a medium priority problem and a total of 109 noxious alien species are being managed. 2) Management of alien plants in Spain has mainly focused, so far, in the application of either mechanical or chemical control measures at a local scale and mostly with short‐term goals in mind. Thus, there is a lack of preventive measures, absence of long‐term monitoring of control actions and few guidelines for prioritization. 3) By using risk assessment schemes, we have identified a preliminary list of 80 potential invasive species, being gardening the most common pathway of introduction. The species with the highest scores, were mainly aquatic plants, and should be prohibited or kept out of trade. Chromolaena odorata (Asteraceae) obtained the highest scores and therefore it might be the species with the highest risk to become invasive in Spain if introduced. 4) We have presented a conceptual framework that compares invaded, non‐invaded and removal sites to quantify invaders’ impacts and to monitor native plant recovery after their removal. In scientific studies, these comparisons are rarely used in concert, and reference sites are scarcely employed to assess native species recovery after removal. Thus, we believe that this comparative approach should be more frequently used to evaluate management effectiveness because it may also be useful to determine possible side‐effects of removal techniques and whether further restoration measures are necessary. 5) Our global literature review has demonstrated that invasion by alien plants is responsible for a local decline in native species richness and abundance. This has been corroborated by monitoring Carpobrotus invaded sites in coastal dunes of Andalucía, where this species has significantly decreased species richness in the communities it invades. 6) Our global literature review has also indicated that, in general, after alien plant removal, the native vegetation has the potential to recover to a pre‐invasion state. The same trend has been found in the case study of Carpobrotus.
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46

Van, der Laan Michael. "Allelopathic interference potential of the alien invader plant Parthenium hysterophorus". Diss., Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-04042007-134659.

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47

Jones, Andrew Thomas. "Alien varieties of Lotus corniculatus L. on new roadside verges". Thesis, University of Hull, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314435.

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48

Sturge, Kathryn Ecroyd. "'The alien within' : translation into German during the Nazi regime". Thesis, University College London (University of London), 1999. http://discovery.ucl.ac.uk/1318013/.

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The thesis examines the policy and practice of literary translation into German during the Nazi regime. It is shown that translation survived, albeit in a constrained form, throughout the period and that heavy official intervention was itself grounded in contradictory attitudes to translation. A consideration of the state regulation and reception of translation demonstrates that translated literature was regarded with suspicion as a potentially harmful invasion of the foreign. Terms used - such as the 'alien within' and the danger of miscegenation - clearly participate in the surrounding discourse of anti-Semitism. However, a database of translations published in the period shows that while such views certainly shaped the selection of genre and source language, there was no simple suppression and numbers remained stable or even rose until 1940. This is accounted for on the one hand by the regime's promotion of certain translations, selected on criteria that draw on notions of literature's cultural specificity as an expression of the Volk soul. An approved translation is compared with its source, showing that consonance with this literary ideology has been enhanced by the detail of translation choices; official reviews further position the text within the boundaries of acceptability. On the other hand, the single largest translated genre of the pre-war period, the Anglo-American detective novel, was not promoted but reviled by the literary bureaucracy. An examination of the source texts and translations of ten detective novels demonstrates that the ideologically marginalised genre adapted itself to the receiving culture by heightening the rule-boundness, strict gender roles and portrayals of authority present in the source texts. The glamorisation of foreign settings remains unaffected, suggesting the persistence of a pre-1933 fascination with Anglo-American culture. The thesis concludes that while the foreignness of foreign literature was fiercely attacked by literary policymakers, it was also promoted in certain, politically acceptable forms and in other cases persisted on its own commercial trajectory despite official disapproval. The study thus contributes to the understanding both of an under-researched area of literary policy in Nazi Germany and of the ideological, institutional and commercial contexts of translation.
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49

Quílez-Badia, Gemma. "Alien invasions : the introduction of zooplankton via ships' ballast water". Thesis, University of Newcastle Upon Tyne, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424152.

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50

Hiley, Christiane. "Alien by degrees : a philosophical and linguistic exploration of citizenship". Thesis, University of Newcastle Upon Tyne, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401853.

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