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Towards creating context-aware dynamically-adaptable business processes using complex event processing / Vers la création de processus métiers sensibles au contexte dynamiquement adaptables en utilisant le traitement des événements complexesHermosillo, Gabriel 05 June 2012 (has links)
En plus de l'utilisation des appareils ubiquitaires qui continue à croître, nous avons accès à d'informations dites contextuelles. Ces informations permettent de connaître l'état de notre environnement et nous aident à prendre les décisions de notre vie quotidienne en fonction du contexte dans lequel nous nous positionnons. La nature statique des processus métiers ne leur permet pas d'être modifiés dynamiquement, les rendant ainsi moins utiles dans un nouveau contexte. Si nous voulons changer le comportement d'un processus métier, nous devons le stopper, le modifier et le redéployer entièrement. Pour répondre à ces problèmes, nous proposons une approche qui permet de représenter des processus métiers sensibles au contexte où les informations de contexte sont considérées comme des événements contrôlés en temps réel. Avec Ceviche, nous intégrons les informations obtenues à partir du contexte avec la capacité d'adaptation des processus métiers en cours d'exécution. De plus, l'une des originalités du cadre logiciel Ceviche vient de la définition d'une opération de désadaptation et de sa mise en oeuvre, car défaire l'adaptation peut facilement se passer mal et conduire à des états non désirés. En outre, avec Ceviche, nous apportons une propriété de stabilité au niveau du traitement des événements complexes. En définissant notre propre langage, Adaptive Business Process Language (ABPL), comme un langage pivot, Ceviche facilite l'utilisation de CEP sans les inconvénients de l'adoption anticipée de l'approche. Nous utilisons une technique de type plug-in qui permet aux événements définis en ABPL d'être utilisés dans pratiquement n'importe quel moteur CEP. / As the use of ubiquitous devices continues to grow, we have more access to pervasive information around us. This information allows us to know the state of our surroundings, and we make decisions of our everyday life based on that context information. The static nature of business processes does not allow them to be dynamically modified, thus leaving them less useful in the new context. If we want to change the behavior of a business process, we need to stop it, modify it and redeploy it entirely.To address these issues, in this thesis we present the Ceviche Framework. We bring forward an approach which allows to represent context-aware business processes where context information is considered as events which are monitored in real-time. With Ceviche we integrate the information obtained from the context with the capability of adapting business process at run-time. Also, one of the original contributions of the Ceviche Framework is the definition of a correct adaptation undoing mechanism and its implementation, as undoing an adaptation can easily go wrong and lead to undesired states and unstable processes.The implementation of the Ceviche Framework offers flexibility and dynamicity properties to the business processes, using a component-based approach, allowing the modification of their bindings at run-time. Moreover, with Ceviche we also provide a stability property in terms of CEP. By defining our own simple language, the Adaptive Business Process Language (ABPL), as a pivot language, Ceviche facilitates the use of CEP without the drawbacks of early adoption. We use a plug-in approach that allows the events defined in ABPL to be used in virtually any CEP engine.
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Yeast adaptation and survival under acute exposure to lethal ethanol stressYang, Jamie Siyu January 2020 (has links)
The ability to respond to stress is universal in all domains of life. Failure to properly execute the stress response compromises the fitness of the organism. Several key stress pathways are conserved from unicellular organisms to higher eukaryotes, so knowledge of how these pathways operate in model organisms is crucial for understanding stress-related diseases and aging in humans. The mechanisms of stress tolerance have been well-studied in the budding yeast Saccharomyces cerevisiae. Yeast respond to diverse stresses by initiating both general and stress-specific responses that generally protect the cells during and after the stress exposure. While previous work has revealed mechanistic insights on adaptation and survival under mild and long-term exposure to stress, how they cope with acute exposure to lethal stress is not well understood.
Here, we combined transcriptional profiling, fitness profiling, and laboratory evolution to investigate how S. cerevisiae survive acute exposure to lethal ethanol stress. By using high throughput methods such as RNA-seq and barcode sequencing of the pooled yeast deletion library, we were able to discover and characterize both existing and novel pathways that yeast utilize to adapt to and survive ethanol stress. We found both ethanol-specific and as well general stress response mechanisms. We were also able to evolve a strain of ethanol under lethal ethanol stress to exhibit a survival of at least an order of magnitude greater than the parental wild-type strain. Additionally, this evolved strain exhibited cross protection to other stresses without compromising bulk growth rate. We found that this strain adapted its global expression levels to a post-stress state, making it more robust to various stresses even under optimal growth conditions.
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Promoting Resiliency in Families of Individuals Diagnosed with an Autism Spectrum Disorder: The Relationship between Parental Beliefs and Family AdaptationWarter, Elizabeth Hill January 2009 (has links)
Thesis advisor: Mary E. Walsh / Comprehensive and collaborative intervention practices with individuals diagnosed with an autism spectrum disorder (ASD) recognize the essential role of the family in effective, long-term treatment of ASDs (e.g., National Research Council, 2001). While some research has focused on the experiences of families of individuals diagnosed with an ASD, there exists a need to better understand what factors detract from or facilitate the family's ability to adapt to their circumstances. Guided by the FAAR model (e.g., Patterson, 1989, 2005) and the Family Systems-Illness Model (e.g., Rolland, 1994, 2003), this current study examined the relationship between two demands or risk factors (i.e., the perceived severity of a child's ASD and the uncertainty related to a child's ASD), three capabilities or protective factors (i.e., optimism, mastery beliefs, and control beliefs), and the family's adaptation to their family member's ASD (i.e., family quality of life). Parents (N=207) of children diagnosed with Autism, PDD-NOS, or Asperger's Syndrome completed a self-report questionnaire assessing perceived ASD severity, the uncertainty regarding their child's ASD, the participant's optimism, mastery, and control beliefs, and the family's quality of life. Results demonstrated that the perceived severity of the child's ASD, the uncertainty related to the child's ASD, dispositional optimism, sense of coherence, and professional-related health locus of control are factors that significantly influence the family's overall quality of life. In addition, dispositional optimism and sense of coherence were found to mediate the relationship between the identified demand factors and the family's quality of life. Results suggest that perceived severity and uncertainty regarding a family member's ASD are demands that have important implications for the family. Additionally, results suggest that optimism and mastery beliefs can play a positive, complex role in the family's adaptation to a family member's ASD. Finally, the results of this study suggest that control beliefs may act in complex and different ways than expected. Theoretical considerations and implications for practice and future research are discussed. / Thesis (PhD) — Boston College, 2009. / Submitted to: Boston College. Lynch School of Education. / Discipline: Counseling, Developmental, and Educational Psychology.
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La parodia quijotesca en el cine = Quixotic Parody in FilmBriones-Manzano, Luisa January 2013 (has links)
Thesis advisor: Elizabeth Rhodes / Esta tesis analiza la función de la parodia en Don Quijote de La Mancha (1605, 1615). A partir de la cual se explora la manera en que tres adaptaciones cinematográficas de la novela de Cervantes reutilizan la estructura paródica de Don Quijote. Estas adaptaciones son Don Quijote cabalga de nuevo de Roberto Gavaldón (México, 1973), Don Quijote de Orson Welles de Jess Franco (España, 1992) y Don Quijote de La Mancha de Rafael Gil (España, 1948). La novela Don Quijote de Cervantes ofrece una estructura de la parodia que los directores de estas tres películas emplean para criticar discursos originalmente parodiados por Cervantes en su novela--la condenación de la literatura de caballerías. Esta tesis explora las nuevas funciones de la parodia quijotesca analizando cómo se representan y transforman en las adaptaciones cinematográficas. El marco teórico tiene en cuenta recientes contribuciones a la teoría de la parodia, que interpreta esta figura más allá de los estudios de la parodia tradicional vinculados a la representación cómica. Puede ser homenaje o crítica seria de los contextos culturales y políticos del momento en el que el nuevo texto, la adaptación, se produce. Igualmente, recientes estudios teóricos sobre adaptaciones cinematográficas desplazan el privilegio tradicionalmente concedido al texto literario. Estas tres adaptaciones cinematográficas de la novela Don Quijote de La Mancha utilizan la parodia original para crear parodias posmodernas de acuerdo a sus propios contextos históricos y artísticos. / Thesis (PhD) — Boston College, 2013. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Romance Languages and Literatures.
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Living with multiple, complex risks of commercial sugarcane farming in KwaZulu-Natal : the role of climate change?Massey, Ruth Thokozile 14 April 2009 (has links)
The aim of this research is to examine the contextual environment in which farmers operate
so as to improve our understanding of the factors shaping vulnerability to climate risk. A key
focus is on the livelihoods of sugarcane farmers, using a case study of small-, medium-scale
(emerging) and large-scale sugarcane farmers in the KwaZulu-Natal Midlands area of Eston
and its surrounds. A social vulnerability assessment was undertaken under the Sustainable
Livelihoods Framework (SLF) to test the hypothesis that climate risk is considered a major
contributing factor to the vulnerability of commercial farmers in KwaZulu-Natal and needs to
be effectively managed. This involved an investigation into the multiple stresses (both
external and internal, on-farm and off-farm, climatic and non climatic) acting on the system.
It is clear that climate change risk and variability is a major, but not the sole contributing
factor to the vulnerability of commercial farmers in this part of KwaZulu-Natal. Climate
change does need to be effectively managed but it will be best done in conjunction with the
management of the other multiple and interacting threats and stresses identified in this study.
Climate change and vulnerability, as well as the other multiple stresses, are acting on an
already vulnerable system, exacerbating and compounding present risks.
This research also explored a number of coping and response strategies that commercial
farmers have adopted in response to the threats and stresses and investigated particularly,
what elements enhance or restrict these strategies (both on-farm and off-farm). These
strategies posses potential as possible future adaptation options. It was found that the issues of access to livelihood assets (social, financial, natural/environmental, physical, human,
knowledge assets and capital under the SLF) are key to the adaptive capacity and the
adaptation strategies that farmers employ. Institutions (both formal and informal) play a
pivotal role in this access to livelihood assets both enabling and restricting access.
In conclusion, this work determined that a focus on only one element, such as climate change,
will not significantly reduce the vulnerability of commercial farmers. There is an interactive,
dynamic and multifaceted network present with a number of factors acting within and from
outside the system. Political, biophysical, social and economic factors interact and combine to
compound vulnerability, requiring more integrative and multiple response strategies.
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Environmental Justice and Flood Adaptation: A Spatial Analysis of Flood Mitigation Projects in Harris County, TexasPravin, Avni 30 April 2019 (has links)
Although literature on flood risk and environmental justice investigates the link between race and ethnicity and vulnerability to floods, few studies examine the distribution of flood mitigation amenities. This study analyzes census tract proximity to flood mitigation projects (FMPs) completed between 2012 and 2016 in Harris County, Texas to determine if a) project location is biased towards economic growth and the urban core; b) areas most impacted by previous floods are prioritized for drainage assistance; and c) if low-income and Latinx populations are being neglected. A spatial error regression analysis indicates that FMPs are significantly proximate to the urban core, net of other factors. Results also indicate no significant relationship between census tract-level Latinx composition, income status, and proximity to FMPs. Finally, built environment characteristics and locations of previous flooding had no significant effect on where projects were placed.
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Management Planning for Combined Sewer Systems in Urban Areas under Climate ChangeRenaud, Thomas 30 April 2012 (has links)
Management of urban stormwater is becoming increasingly difficult due to an anticipated increase in precipitation and extreme storm events that are expected under climate change. The goal of this research is to develop an approach that effectively accounts for the uncertain conditions that may occur under climate change and to develop best management practices to manage stormwater in urban areas. This presentation focuses on management of stormwater and combined sewage in Worcester, MA, where approximately four square miles of the downtown area is serviced by a combined sewer system. The EPA Stormwater Management Model was used to determine the impacts of storms on the urban environment for future conditions. This model was used to simulate discharges of selected design storms associated with a range of climate change scenarios. Various design storms were simulated in SWMM for 2010, 2040, and 2070 under high, moderate, and low climate change scenarios. Alternative best management practices were assessed in terms of specific metrics that included flood volumes and combined sewer overflow volumes through the Worcester sewer system. Cost evaluations were used to identify appropriate best management strategies for managing the combined sewer system under future scenarios. A design cost approach and net benefits approach were used to analyze different options for managing stormwater under climate change. Both of these approaches utilize the concept of risk analyze to determine expected values of both costs and benefits for different options under different climate change scenarios. Results for the design cost approach indicate that providing upstream underground storage in select locations throughout the Worcester combined sewer system is the most cost-effective strategy. In addition, increased pumping capacity at the Quinsigamond Avenue Combined Sewer Overflow Storage and Treatment Facility (QCSOSTF) should be included for this option. However, it was determined that only select upstream storage is the most beneficial option under the net benefits approach as increased pumping capacity at the QCSOSTF was determined to be too costly due to the additional costs of CSO treatment required at the facility. The Worcester case study provides an ideal context for assessing the relative advantages of full treatment at the wastewater treatment facility, limited treatment at a centralized CSO treatment facility, decentralized storage options, and low impact stormwater controls. It also allows for an assessment of decision making methods for controlling flows and loads from the Worcester system. Comparisons between Worcester and other case studies provide a foundation for understanding how stormwater and combined sewer systems can be managed given climate change uncertainty.
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Attitude Synchronization of Spacecraft Formation with Optimization and Adaptation of Consensus Penalty TermsZhang, Kewen 23 April 2013 (has links)
The contribution of this thesis is on the temporal adjustment of the consensus weights, as applied to spacecraft formation control. Such an objective is attained by dynamically enforcing attitude synchronization via coupling terms included in each spacecraft controller. It is assumed that each spacecraft has identical dynamics but with unknown inertia parameters and external disturbances. By augmenting a standard adaptive controller that accounts for the unknown parameters, made feasible via an assumption on parameterization, with adaptation of the consensus weights, one opts to improve spacecraft synchronization. The coupling terms, responsible for enforcing synchronization amongst spacecraft, are weighted dynamically in proportion to the disagreement between the states of the spacecraft. The time adjustment of edge-dependent gains as well as the special cases of node-dependent and agent-independent constant gains are derived using Lyapunov redesign methods. The proposed adaptive control architectures which allow for adaptation of both parameter uncertainties and consensus penalty terms are demonstrated via extensive numerical studies of spacecraft networks with limited connectivity. By considering the sum of deviation-from-the-mean and rotational kinetic energy as appropriate metrics for synchronization and controller performance, the numerical studies also provide insights on the choice of optimal consensus gains.
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Epithelial cell adaptation to supernumerary centrosomesRhys, Alexander Daniel January 2017 (has links)
The centrosome is the main microtubule-organising centre in animal cells; important to assemble a bipolar mitotic spindle ensuring proper chromosome segregation and genomic stability. Whereas correct centrosome number (1-2) is tightly maintained in normal cells, cancer cells usually have an increased number of centrosomes (>2), termed centrosome ampli cation. Centrosome ampli cation has been correlated with aneuploidy, increased tumour grade, chemoresistance and overall poor prognosis. Cancer cells primarily adapt to supernumerary centrosomes by clustering them into two poles resulting in a `normal' pseudo-bipolar mitosis. Undermining centrosome clustering is a potential target for cancer-speci c treatment. Indeed, depleting the kinesin HSET has already been shown to speci cally kill cancer cells by impairing the centrosome clustering mechanism. However, it is unclear whether this process requires adaptation or it is inherent to all cell types. Using a panel of non-transformed cell lines, we observed that cells expressing Ecadherin have ine cient clustering mechanisms compared to cell lines without E-cadherin. Loss of E-cadherin (siRNA/CRISPR) promotes centrosome clustering and survival of epithelial cells with multiple centrosomes. In addition, loss of DDR1, involved in regulating cortical contractility downstream of E-cadherin, increases centrosome clustering in epithelial cells. Using Atomic Force Microscopy we con rmed that indeed loss of E-cadherin leads to increased cortical contractility in mitotic cells. Inhibition of actomyosin contractility prevents e cient clustering in cells that do not express E-cadherin, further suggesting that it is important for this process. Loss of E-cadherin and DDR1 is strongly correlated with high levels of centrosome ampli cation in breast cancer cell lines suggesting that these changes are an important adaptation mechanism to centrosome amplification.
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Effects of sex and competition on evolutionary survival of Chlamydomonas reinhardtii populations in deteriorating environmentsPetkovic, Nikola January 2018 (has links)
Ongoing global change has made understanding the factors that affect adaptation and survival of populations in the context of changing environments a central problem in evolutionary biology. Special focus has been given to the probability of survival through genetic adaptation to lethal environments; a process termed evolutionary rescue. Many studies of this process, both theoretical and empirical, have been carried out over the last two decades. As a result, we now understand how a number of factors may affect the probability of population survival. However, two factors that are known to affect evolutionary responses, mode of reproduction and interspecific interaction, have received limited attention. The main aim of my work was to investigate whether and how mode of reproduction and negative interspecies interactions (competition) affect the probability of evolutionary rescue. To achieve this goal, I set up a series of selection experiments, by propagating populations of unicellular alga Chlamydomonas reinhardtii in various stressful conditions, and monitored their survival and fitness. To investigate the effect of sex in these experiments, I manipulated mode of reproduction, by constructing the experimental populations allowed to reproduce either only sexually or asexually or both. To investigate the effect of competition, I manipulated the presence of the competitor(s) in the experimental populations, by cultivating them either in presence or absence of the competitor. I first tested the effect of rate of environmental deterioration and mode of reproduction on extinction dynamics and evolutionary rescue of the experimental populations. I found positive correlation between the rate of extinctions and the rate of environmental deterioration. The experiment revealed an interaction between mode of reproduction and the rate of deterioration, manifested through significantly reduced extinction rate of sexual populations relative to asexual populations in environment deteriorating at intermediate rate. I then investigated the effect of sex and competition on the probability of evolutionary rescue, by propagating the experimental populations in environment deteriorating in a simple way (the change comprising a single abiotic factor) and complex way (the change of both abiotic and biotic factors). I found the negative effect of competition on the probability of evolutionary rescue, and beneficial effect of sex in both types of environmental deterioration, reflected in higher number of rescued populations relative to asexual group. I then tested whether phylogenetic relatedness between a competitor and the focal species and the extent of their ecological similarity affect the likelihood of evolutionary rescue, by subjecting the experimental populations to the presence of 10 different competitors, isolated from two different types of habitats, and each being positioned on a different branch of the phylogenetic tree of Chlamydomonas genus. The probability of evolutionary rescue was contingent on the identity of a competitor species, but the results showed no significant effects of phylogenetic relatedness and ecological similarity. Finally, I investigated which experimental factors could potentially select for the long-term maintenance of sex, by subjecting the experimental populations to different types of selective environments (directional and fluctuating change of abiotic factors, the presence of the competitor) and monitoring the frequency of sex over the course of time. No selective environment significantly increased the rate of sex in the experimental populations. In contrast, I found reduction in frequency of sex in the populations subjected to fluctuating environmental change. My results demonstrate that both mode of reproduction and competition affect the probability of evolutionary rescue, which is generally positively affected by sex and negatively affected by competition. However, these general effects may be altered by other factors, namely mode of environmental change and the identity of the competitor species.
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