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Geospatialt beslutsstöd - nyckeln till strategiska beslutJones, Julia, Nordström, Fredrik January 2022 (has links)
Tillståndsprocessen för att bedriva miljöfarlig verksamhet är manuell och ineffektiv vilket hämmar svenska företag i deras klimatarbete. Geospatial information har till följd av lokaliseringsprincipen i miljöbalken en central roll inom samhällsbyggnad och dess planering för placering av investeringar. Det finns i dagsläget inget geospatialt beslutsstödsystem (SDSS) som ämnar att underlätta för verksamhetsutövare i tillståndsprocessen vid beslut som rör placering av nya investeringar i industri. Syftet med studien var att utveckla en IT-artefakt med intentionen att stödja processen samt beslutsfattande för industriföretag i skapandet av en tillståndsansökan för miljöfarlig verksamhet. Detta genom att ta fram en webbapplikation som ska fungera som ett processtöd för användaren genom att redogöra de nödvändiga stegen som ingår i en miljötillståndsansökan med fokus på de aspekter som inkluderar geospatial data och information. Målet är att artefakten i dessa steg ska fungera som ett hjälpmedel för verksamhetsutövaren att fatta strategiska beslut kring geografisk plats för nya investeringar i industri. Studien använder sig av Design Science Research Methodology (DSRM) och har hämtat in empiri genom fokusgruppsintervjuer. Arbetet resulterade i en IT-artefakt som visar att det är möjligt att implementera denna typ av lösning på problemet samt de identifierade designprinciperna som implementerades. / The permit process for conducting environmentally hazardous activities is manual and inefficient, which impedes Swedish companies in their climate action. As a result of the “location principle” in the Swedish Environmental Code, spatial information has a central role in community building and its planning for location of investments. There is currently no spatial decision support system (SDSS) that aims to make it easier for operators to make decisions regarding the location of new investments in industry during the permit process. The purpose of the study was to develop an IT artefact with the intention to support the process and decision making for industrial companies in the creation of permit applications for environmentally hazardous activities. This by developing a web application that will function as a process support for the user by describing the necessary steps that are included in an environmental permit application with a focus on the aspects that include spatial data and information. The aim is that the artifact in these steps should function as an aid for the operator to make strategic decisions about the geographical location for new investments in industry. This research uses Design Science Research Methodology (DSRM) and has obtained empirical data through focus group interviews. The work resulted in an IT artifact that proves that it is possible to implement this kind of solution to the problem and the identified design principles that were implemented.
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PI3K in juvenile myelomonocytic leukemiaGoodwin, Charles B. 20 November 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Juvenile Myelomonocytic Leukemia (JMML) is rare, fatal myeloproliferative disease (MPD) affecting young children, and is characterized by expansion of monocyte lineage cells and hypersensitivity to Granulocyte Macrophage-Colony Stimulating Factor (GM-CSF) stimulation. JMML is frequently associated with gain-of-function mutations in the PTPN11 gene, which encodes the protein tyrosine phosphatase, Shp2. Activating Shp2 mutations are known to promote hyperactivation of the Ras-Erk signaling pathway, but Akt is also observed to have enhanced phosphorylation, suggesting a potential role for Phosphatidylinositol-3-Kinase (PI3K)-Akt signaling in mutant Shp2-induced GM-CSF hypersensitivity and leukemogenesis.
Having demonstrated that Class IA PI3K is hyperactivated in the presence of mutant Shp2 and contributes to GM-CSF hypersensitivity, I hypothesized the hematopoietic-specific Class IA PI3K catalytic subunit p110δ is a crucial mediator of mutant Shp2-induced PI3K hyperactivation and GM-CSF hypersensitivity in vitro and MPD development in vivo. I crossed gain-of-function mutant Shp2 D61Y inducible knockin mice, which develop fatal MPD, with mice expressing kinase-dead mutant p110δ D910A to evaluate p110δ’s role in mutant Shp2-induced GM-CSF hypersensitivity in vitro and MPD development in vivo. As a comparison, I also crossed Shp2 D61Y inducible knockin mice with mice bearing inducible knockout of the ubiquitously expressed Class IA PI3K catalytic subunit, p110α. I found that genetic interruption of p110δ, but not p110α, significantly reduced GM-CSF-stimulated hyperactivation of both the Ras-Erk and PI3K-Akt signaling pathways, and as a consequence, resulted in reduced GM-CSF-stimulated hyper-proliferation in vitro. Furthermore, I found that mice bearing genetic disruption of p110δ, but not p110α, in the presence of gain-of-function mutant Shp2 D61Y, had on average, smaller spleen sizes, suggesting that loss of p110δ activity reduced MPD severity in vivo.
I also investigated the effects of three PI3K inhibitors with high specificity for p110δ, IC87114, GDC-0941, and GS-9820 (formerly known as CAL-120), on mutant Shp2-induced GM-CSF hypersensitivity. These inhibitors with high specificity for p110δ significantly reduced GM-CSF-stimulated hyperactivation of PI3K-Akt and Ras-Erk signaling and reduced GM-CSF-stimulated hyperproliferation in cells expressing gain-of-function Shp2 mutants.
Collectively, these findings show that p110δ-dependent PI3K hyperactivation contributes to mutant Shp2-induced GM-CSF hypersensitivity and MPD development, and that p110δ represents a potential novel therapeutic target for JMML.
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The effect of hypoxia on ER-β expression in the lung and cultured pulmonary artery endothelial cellsSelej, Mona M.A. 12 March 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / 17-β estradiol (E2) exerts protective effects in hypoxia-induced pulmonary hypertension (HPH) via endothelial cell estrogen receptor (ER)-dependent mechanisms. However, the effects of hypoxia on ER expression in the pulmonary-right ventricle (RV) axis remain unknown. Based on previous data suggesting a role of ER-β in mediating E2 protection, we hypothesized that hypoxia selectively up-regulates ER-β in the lung and pulmonary endothelial cells.
In our Male Sprague-Dawley rat model, chronic hypoxia exposure (10% FiO2) resulted in a robust HPH phenotype associated with significant increases in ER- β but not ER-α protein in the lung via western blotting. More importantly, this hypoxia-induced ER-β increase was not replicated in the RV, left ventricle (LV) or in the liver. Hence, hypoxia-induced ER-β up-regulation appears to be lung-specific. Ex vivo, hypoxia exposure time-dependently up-regulated ER-β but not ER-α in cultured primary rat pulmonary artery endothelial cells (RPAECs) exposed to hypoxia (1% O2) for 4, 24 or 72h. Furthermore, the hypoxia induced ER-β protein abundance, while not accompanied by increases in its own transcript, was associated with ER-β nuclear translocation, suggesting increase in activity as well as post-transcriptional up-regulation of ER-β.
Indeed, the requirement for ER-β activation was indicated in hypoxic ER-βKO mice where administration of E2 failed to inhibit hypoxia-induced pro-proliferative ERK1/2 signaling. Interestingly, HIF-1α accumulation was noted in lung tissue of hypoxic ER-βKO mice; consistent with previously reported negative feedback of ER-β on HIF-1α protein and transcriptional activation. In RAPECs, HIF-1 stabilization and overexpression did not replicate the effects of ER- β up-regulation seen in gas hypoxia; suggestive that HIF-1α is not sufficient for ER-β up- regulation. Similarly, HIF-1 inhibition with chetomin did not result in ER-β down-regulation. HIF-1α knockdown in RPAECs in hypoxic conditions is currently being investigated.
Hypoxia increases ER- β, but not ER-α in the lung and lung vascular cells. Interpreted in context of beneficial effects of E2 on hypoxic PA and RV remodeling, our data suggest a protective role for ER-β in HPH. The mechanisms by which hypoxia increases ER-β appears to be post-transcriptional and HIF-1α independent. Elucidating hypoxia-related ER-β signaling pathways in PAECs may reveal novel therapeutic targets in HPH.
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Identification and characterization of Ascl1-expressing cells in maternal liver during pregnancyKumar, Sudhanshu 01 August 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / During pregnancy, maternal liver exhibits robust growth to meet the metabolic demands of the developing placenta and fetus. Although hepatocyte hypertrophy and hyperplasia are seen in the maternal liver, the molecular and cellular mechanisms mediating the maternal hepatic adaptations to pregnancy is poorly understood. Previous microarray analysis revealed a most upregulated gene named Ascl1, a transcription factor essential for neural development, in the maternal liver at mid-gestation. The aims of the study were to (1) validate the activation of Ascl1 gene; (2) identify Ascl1-expressing cells; and (3) determine the fate of Ascl1-expressing cells, in the maternal liver during the course of gestation. Timed pregnancy was setup in mice and the maternal livers were collected at various stages of gestation. Maternal hepatic Ascl1 mRNA expression was evaluated by qRT-PCR and northern blotting. The results demonstrated that the transcript level of maternal hepatic Ascl1 is exponentially increased during the second half of pregnancy in comparison with a non-pregnant state. Using a Ascl1-GFP mouse model generated by others to monitor the behavior of neural progenitor cells, we found that maternal hepatic Ascl1-expressing cells are non-parenchymal cells, very small in size, and expanding during pregnancy. To map the fate of this cell population, we generated an in vivo tracing mouse model named Ascl1-CreERT2/ROSA26-LacZ. Using this model, we permanently labeled maternal hepatic Ascl1-expressing cells at midgestation by giving tamoxifen and analyzed the labeled cells in the maternal liver prior to parturition. We observed that the initial small Ascl1-expressing cells undergoing expansion at mid-gestation eventually became hepatocyte-like cells at the end stage of pregnancy. Taken together, our findings strongly suggest that Ascl1-expressing cells represent a novel population of hepatic progenitor cells and they can differentiate along hepatocyte lineage and contribute to pregnancy-induced maternal liver growth. Further studies are needed to firmly establish the nature and property of maternal hepatic Ascl1-expressing cells. At this stage, we have gained significant insights into the cellular mechanism by which the maternal liver adapts to pregnancy.
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Interactive pattern mining of neuroscience dataWaranashiwar, Shruti Dilip 29 January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Text mining is a process of extraction of knowledge from unstructured text documents. We have huge volumes of text documents in digital form. It is impossible to manually extract knowledge from these vast texts. Hence, text mining is used to find useful information from text through the identification and exploration of interesting patterns. The objective of this thesis in text mining area is to find compact but high quality frequent patterns from text documents related to neuroscience field. We try to prove that interactive sampling algorithm is efficient in terms of time when compared with exhaustive methods like FP Growth using RapidMiner tool. Instead of mining all frequent patterns, all of which may not be interesting to user, interactive method to mine only desired and interesting patterns is far better approach in terms of utilization of resources. This is especially observed with large number of keywords. In interactive patterns mining, a user gives feedback on whether a pattern is interesting or not. Using Markov Chain Monte Carlo (MCMC) sampling method, frequent patterns are generated in an interactive way. Thesis discusses extraction of patterns between the keywords related to some of the common disorders in neuroscience in an interactive way. PubMed database and keywords related to schizophrenia and alcoholism are used as inputs. This thesis reveals many associations between the different terms, which are otherwise difficult to understand by reading articles or journals manually. Graphviz tool is used to visualize associations.
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Defining the mechanism of prostaglandin E₂-enhanced hematopoietic stem and progenitor cell homingSpeth, Jennifer M. 02 April 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Hematopoietic stem cell (HSC) transplantation is a lifesaving therapy for a number of hematological disorders. However, to be effective, transplanted HSCs must efficiently “home” to supportive niches within the bone marrow. Limited HSC number and poor function are complications of transplant in some circumstances, and can lead to delayed engraftment and immune reconstitution, or in some cases, bone marrow failure. Enhancing HSC homing is a strategy to improve stem cell transplantation efficiency. We have previously shown that ex vivo treatment of mouse or human HSCs with 16-16 dimethyl PGE2 (dmPGE2) increases their bone marrow homing efficiency and engraftment, resulting in part from upregulation of surface CXCR4 expression. We now show that pulse-treatment of mouse or human HSPCs with dmPGE2 stabilizes HIF1α in HSPCs, and that similar treatment with the hypoxia mimetic DMOG produces analogous effects to dmPGE2 on HSPC CXCR4 expression and homing. This suggests that HIF1α is responsible for PGE2’s enhancing effects on HSPCs. Pharmacological inhibition of HIF1α stabilization in vitro with Sodium Nitroprusside (SNP), confirms the requirement of HIF1α for dmPGE2-enhanced migration and CXCR4 upregulation. Additionally, we confirm the requirement for HIF1α in dmPGE2-enhanced in vivo homing using a conditional knockout mouse model of HIF1α gene deletion. Finally, we validate that the hypoxia response element located 1.3kb from the transcriptional start site within the CXCR4 promoter is required for enhanced CXCR4 expression after PGE2 treatment. Interestingly, we also observe an increase in the small GTPase Rac1 after dmPGE2 treatment, as well as a defect in PGE2-enhanced migration and CXCR4 expression in Rac1 knockout HSPCs. Using state-of-the-art imaging technology we, confirm an increase in Rac1 and CXCR4 colocalization after dmPGE2 treatment that likely explains enhanced sensitivity of PGE2-treated HSPCs to SDF-1. Taken together, these results define a precise mechanism through which ex vivo pulse treatment of HSPC with dmPGE2 enhances HSPC function through alterations in cell motility and homing, and describe a role for hypoxia and HIF1α in enhancement of hematopoietic transplantation.
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Cracked skulls and social liability : relating helmet safety messages to motorcycle ridersVoight, Susan Amy 02 April 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Grounded theory analysis, informed by a socio-cultural lens, was applied to the narratives of eighteen motorcycle riders in order to understand, from the rider’s perspective, receptivity to warning messages regarding motorcycle helmet use. This study relied upon narrative analysis to identify patterns in communication that surround motorcycle riders’ experiences. Socio-cultural cues identified importance in the process of interest development in motorcycle riding, search for information regarding motorcycle riding, response to danger within the motorcycle riding experience, and attitude toward protection messages. Narratives specific to danger, or experiences of motorcycle accidents were analyzed for comparison with fear appeal theory. Special focus was applied to Terror Management Theory (TMT) and applied to the communication surrounding the real experiences of motorcycle accident and the perceived threat of danger while motorcycle riding. Communication evidencing relational influence was examined for examples of socially constructed interpretation of social identity and an individual rider's perspective of their lifeworld. The analysis revealed evidence of the TMT concept of burying or denying thoughts of danger. The TMT concept of lifeworld influence on behavior was evidenced in riders who did not accept warning messages involving helmet use. Examples of attitude and behavior change where present in two study participants’ narratives that described experience of severe injury and also the death of a friend. The riders cited these occurrences as experiences that inhibited their previous behavior of placing thoughts of motorcycle injury and death in the back of mind. Although small in number, this participant group offered multiple categorizations of rider descriptions. The narratives offered distinction in time of life when riding interest developed. As well, motorcycle training facilities were often noted as a source of communication from which riders obtained influence on their future behaviors. From this information insight was gained to offer suggestions for future research on time of message delivery. Riders who develop interest in riding as adults represent a category on which to focus preliminary educational messages. Individuals who have not yet developed an interest in motorcycle riding may benefit from societal cues that demonstrate safe riding behavior. Future research in mass media appeals focused on motorcycle riders are suggested, as is development of educational programs for delivery to high school audiences.
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Serum response factor-dependent regulation of smooth muscle gene transcriptionChen, Meng 07 July 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Several common diseases such as atherosclerosis, post-angioplasty restenosis, and graft vasculopathies, are associated with the changes in the structure and function of smooth muscle cells. During the pathogenesis of these diseases, smooth muscle cells have a marked alteration in the expression of many smooth muscle-specific genes and smooth muscle cells undergo a phenotypic switch from the contractile/differentiated status to the proliferative/dedifferentiated one. Serum response factor (SRF) is the major transcription factor that plays an essential role in coordinating a variety of transcriptional events during this phenotypic change. The first goal of my thesis studies is to determine how SRF regulates the expression of smooth muscle myosin light chain kinase (smMLCK) to mediate changes in contractility. Using a combination of transgenic reporter mouse and knockout mouse models I demonstrated that a CArG element in intron 15 of the mylk1 gene is necessary for maximal transcription of smMLCK. SRF binding to this CArG element modulates the expression of smMLCK to control smooth muscle contractility. A second goal of my thesis work is to determine how SRF coordinates the activity of chromatin remodeling enzymes to control expression of microRNAs that regulate the phenotypes of smooth muscle cells. Using both mouse knockout models and in vitro studies in cultured smooth muscle cells I showed how SRF acts together with Brg1-containing chromatin remodeling complexes to regulate expression of microRNAs-143, 145, 133a and 133b. Moreover, I found that SRF transcription cofactor myocardin acts together with SRF to regulate expression of microRNAs-143 and 145 but not microRNAs-133a and 133b. SRF can, thus, further modulate gene expression through post-transcriptional mechanisms via changes in microRNA levels. Overall my research demonstrates that through direct interaction with a CArG box in the mylk1 gene, SRF is important for regulating expression of smMLCK to control smooth muscle contractility. Additionally, SRF is able to harness epigenetic mechanisms to modulate expression of smooth muscle contractile protein genes directly and indirectly via changes in microRNA expression. Together these mechanisms permit SRF to coordinate the complex phenotypic changes that occur in smooth muscle cells.
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Designing and experimenting with e-DTS 3.0Phadke, Aboli Manas 29 August 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / With the advances in embedded technology and the omnipresence of smartphones,
tracking systems do not need to be confined to a specific tracking environment. By introducing mobile devices into a tracking system, we can leverage their mobility and the
availability of multiple sensors such as camera, Wi-Fi, Bluetooth and Inertial sensors. This thesis proposes to improve the existing tracking systems, enhanced Distributed Tracking System (e-DTS 2.0) [19] and enhanced Distributed Object Tracking System (eDOTS)[26], in the form of e-DTS 3.0 and provides an empirical analysis of these improvements. The enhancements proposed are to introduce Android-based mobile devices into the tracking system, to use multiple sensors on the mobile devices such as the camera, the Wi-Fi and Bluetooth sensors and inertial sensors and to utilize possible resources that may be available in the environment to make the tracking opportunistic. This thesis empirically validates the proposed enhancements through the experiments carried out on a prototype of e-DTS 3.0.
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Assessment of the dopamine system in addiction using positron emission tomographyAlbrecht, Daniel Strakis January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Drug addiction is a behavioral disorder characterized by impulsive behavior and continued intake of drug in the face of adverse consequences. Millions of people suffer the financial and social consequences of addiction, and yet many of the current therapies for addiction treatment have limited efficacy. Therefore, there is a critical need to characterize the neurobiological substrates of addiction in order to formulate better treatment options. In the first chapter, the striatal dopamine system is interrogated with [11C]raclopride PET to assess differences between chronic cannabis users and healthy controls. The results of this chapter indicate that chronic cannabis use is not associated with a reduction in striatal D2/D3 receptor availability, unlike many other drugs of abuse. Additionally, recent cannabis consumption in chronic users was negatively correlated with D2/D3 receptor availability. Chapter 2 describes a retrospective analysis in which striatal D2/D3 receptor availability is compared between three groups of alcohol-drinking and tobacco-smoking subjects: nontreatment-seeking alcoholic smokers, social-drinking smokers, and social-drinking non-smokers. Results showed that smokers had reduced D2/D3 receptor availability throughout the striatum, independent of drinking status. The results of the first two chapters suggest that some combustion product of marijuana and tobacco smoke may have an effect on striatal dopamine concentration. Furthermore, they serve to highlight the effectiveness of using baseline PET imaging to characterize dopamine dysfunction in addictions. The final chapter explores the use of [18F]fallypride PET in a proof-of-concept study to determine whether changes in cortical dopamine can be detected during a response inhibition task. We were able to detect several cortical regions of significant dopamine changes in response to the task, and the amount of change in three regions was significantly associated with task performance. Overall, the results of Chapter 3 validate the use of [18F]fallypride PET to detect cortical dopamine changes during a impulse control task. In summary, the results reported in the current document demonstrate the effectiveness of PET imaging as a tool for probing resting and activated dopamine systems in addiction. Future studies will expand on these results, and incorporate additional methods to further elucidate the neurobiology of addiction.
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