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Search Results: 1 - 10 of 659 matches for " Hagen "
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Mechanism of Intraplate Earthquakes and Anthropogenic Causes in USA  [PDF]
Marilia Hagen
Natural Science (NS) , 2015, DOI: 10.4236/ns.2015.79047
Abstract: In this paper we carried out an investigation about the possible causes for the enhancement of earthquakes in USA the last seven years. Our statistical and physical models indicated that the increased evolution of events in the country depends from the human actions. For further analysis we divided the country into three main seismological regions: western, central and, eastern. We roughly classified the areas by their thickness of Earth’s crust in a variation 25-45-25 km. The thickest area is in the mid-continent and most of this region are part of the Great Plains. In our study we are going to investigate the reason for the Mississippi Lime in Oklahoma a very thick area, started an unusual earthquake activity since 2010, most at Oklahoma/Kansas border. In this region also there are many anthropogenic activities concerning with the waste water wells and more than 4000 of them are active in the state. Wastewater disposal wells typically operate for longer duration and inject much more fluid than hydraulic fracturing, making them more likely to induce earthquakes. Enhanced oil recovery injects fluid into rock layers where oil and gas have already been extracted, while wastewater injection often occurs in never-before-touched rocks. Therefore, wastewater injection can raise pressure levels more than enhanced oil recovery, and thus increases the likelihood of induced earthquakes. Most injection wells do not trigger felt earthquakes. A combination of many factors is necessary for injection to induce felt earthquakes. These include the injection rate and total volume injected; the presence of faults or unknown fractures that are large enough to produce felt earthquakes; stresses that are large enough to produce earthquakes; and the presence of pathways for the fluid pressure to travel from the injection point to faults. Finally other causes of human action triggering earthquakes fluid injection, hydraulic fracturing, enhanced oil recovery, mining, nuclear explosions, some of them will be mentioned and investigated in this paper. We also intend to explain why not all the waste wells are triggering earthquakes and how it would be strongly attached to the unevenness of the Earth’s crust.
Deep and Ultra-Deep Earthquakes Worldwide, Possible Anomalies in South America  [PDF]
M. Hagen, A. Azevedo
Natural Science (NS) , 2018, DOI: 10.4236/ns.2018.106022
Abstract: The aim of this paper is to evaluate the worldwide variation of deep and ultra-deep earthquakes (DQ and UDQ) during the period 1996-2017. This project found only three locations around the globe presenting this kind of seismicity. Although there are other global settings showing deep seismicity, they are not periodical and cannot be considered by a statistical view. The three areas with intense activity for DQ and UDQ events are located mostly in subduction areas. The largest variations of DQ and UDQ border the Pacific Ocean and include the North Pacific, South Pacific, and South America. The major difference in this set is that the first two sites are subduction zones and the South American occurrences happened in the interior of the continent. Another anomaly is an internal layer between 300 - 500 km in South America that shows no tremors in the period studied. However, below 500 km activity reappears, even at extreme depths of up to 650 km. We suggested that the reason for those occurrences would be due to an anomaly in the asthenosphere in this region. This anomaly would probably be presenting a breakable material that was pushed by the Nazca platform against the South America plate. Other depths below 100 km in all the regions are discussed as well. We suggested that the reason for those occurrences was an anomaly created in the asthenosphere as part of the process of the South America collision with the Nazca plate. Part of the Nazca plate has subducted below South America, creating a slab as deep as 500 km. The convergent slab is still moving against South America and sinking due to the gravity and rotation of the Earth. The discrepancies in the occurrences we tracked at different locations indicated that this slab had different thicknesses around South America. We found similar results for Vanuatu and Fiji; in these regions UDQ events occur at the subduction zones under the ocean with depths greater than 700 km. Here, a possible explanation is that part of the lithosphere is subducted at these depths and is causing tremors.
Possible Connections between Seasons and Ultra-Deep Earthquakes Worldwide  [PDF]
Marilia Hagen, A. Azevedo
Natural Science (NS) , 2018, DOI: 10.4236/ns.2018.107029
Abstract: The aim of this investigation is to find possible changes in ultra-deep earthquakes (UDQ) during different seasons of the year. In the acquisition of data for our previous work we observed an inexplicable pattern of growth of ultra-deep tremors (UDQ) during the studied period. Apparently, there is no viable explanation for growth occurring at such a level, presumably in the asthenosphere. Current research and theories developed for the inner layers of the Earth do not explain such variations. Therefore, a possible explanation would be in external factors such as the seasons of the year, which are determined by changes in the Earth’s axial tilt, and therefore the portion of the earth that is angled toward the sun. This paper focuses exclusively on UDQ events. To simplify the calculations, we consider four main locations; this includes one more region than our previous paper but includes only UDQ data. The results showed that during spring and autumn UDQ events grew slightly in both Northern and Southern Hemispheres. It is also suggested that a contributor to UDQ events is friction from the subducting lithosphere against the continental plates.
Seasonality and Tectonic Influences on Subduction Zones for Ultra-Deep Earthquakes  [PDF]
Marilia Hagen, Anibal Azevedo
Open Journal of Earthquake Research (OJER) , 2018, DOI: 10.4236/ojer.2018.74014
Abstract:
Our previous research has found that deep or very deep earthquakes can be influenced by different seasons of the year. It also indicates that other factors may impact the seasonality in addition to these external parameters. This would explain why the response from Northern Hemisphere and Southern Hemisphere for the seasons is different. In the current research, we will focus on very deep earthquakes over a very long period, 1950-2017, which have high magnitude of M ≥ 6 with depth ≥ 500 km and named ultra-deep earthquakes (UDQ). We will separate such events by coordinates of each subduction area located in the Pacific Ring of Fire to find which effects the seasons have on these specific areas. Former tomographic studies in such regions pointed out that each area mentioned had systematic differences in the slab configuration along arcs. Our conclusions showed that those discrepancies may influence the enhancement of earthquakes in some seasons or months.
Seasonality Variability and Periodicities for Ultra-Deep Earthquakes Worldwide  [PDF]
Marilia Hagen, Anibal Azevedo
Open Journal of Earthquake Research (OJER) , 2019, DOI: 10.4236/ojer.2019.81001
Abstract:
Our last study found that deepest-depth earthquakes with larger magnitudes (M6 or above) showed seasonality, which is dependent on the area searched. The main results indicated strong evidence that the causes for the delays in enhancements along the period investigated were due to the tectonics also, not only the season. Therefore, if the inquiry was about an area in Northern Hemisphere, the season in which the increases occurred is different than the season in the Southern Hemisphere. Also, higher latitudes in the Northern Hemisphere or around the Equator, displayed seasonality similarly where the tremors appear to increase during the Spring and Summer. This did not happen to the Southern Hemisphere where disturbances and anomalies occurred without showing much connection to the seasons in the analyzed period. However, some of the regions presented periodicities independent from the seasons.
Prolonged Opioid-Sparing Pain Control after Hemorrhoidectomy with Liposome Bupivacaine: Results from a Cohort of 95 Patients  [PDF]
Allen B. Jetmore, Douglas Hagen
Pain Studies and Treatment (PST) , 2016, DOI: 10.4236/pst.2016.41002
Abstract: The objective of this retrospective study was to examine the effects of an intraoperative injection of liposome bupivacaine on the quality and duration of postsurgical pain control, patient satisfaction, and opioid use in a cohort of patients undergoing hemorrhoidectomy in an outpatient setting. Patients underwent ambulatory hemorrhoidectomy conducted by a single surgeon. Liposome bupivacaine 266 mg/20 mL was administered via infiltration at the end of surgery. After discharge, pain-related outcomes were assessed via telephone interviews. Outcomes of interest included first onset of pain after surgery, patient-reported pain intensity (0 = no pain; 10 = worst pain imaginable), time to first use of orally administered opioids after surgery, number of opioid tablets consumed postsurgery, and patient’s satisfaction with postsurgical pain control. A total of 95 patients were included; the average number of hemorrhoids excised was 3.0 (median, 2.7) per patient. Mean time to first onset of pain after surgery was 36 hours; mean time to first consumption of postsurgical opioids was 38 hours. Mean pain intensity scores remained <5 through 72 hours after surgery. The average number of opioid analgesic tablets consumed after surgery was 12.4; 13% (12/95) of patients required no postsurgical opioids. Seventy-five percent of patients reported being “very satisfied” or “perfectly satisfied” with their overall pain control. No liposome bupivacaine-related adverse events were observed. A single intraoperative injection of liposome bupivacaine safely facilitated ambulatory hemorrhoidectomy, eliminated the need for intravenous opioids, minimized opioid use, and was associated with high levels of patient satisfaction.
Oxygen versus Reactive Oxygen in the Regulation of HIF-1: The Balance Tips
Thilo Hagen
Biochemistry Research International , 2012, DOI: 10.1155/2012/436981
Abstract: Hypoxia inducible factor (HIF) is known as the master regulator of the cellular response to hypoxia and is of pivotal importance during development as well as in human disease, particularly in cancer. It is composed of a constitutively expressed β subunit (HIF-1β) and an oxygen-regulated α subunit (HIF-1α and HIF-2α), whose stability is tightly controlled by a family of oxygen- and iron-dependent prolyl hydroxylase enzymes. Whether or not mitochondria-derived reactive oxygen species (ROS) are involved in the regulation of Hypoxia Inducible Factor-1α has been a matter of contention for the last 10 years, with equally compelling evidence in favor and against their contribution. A number of recent papers appear to tip the balance against a role for ROS. Thus, it has been demonstrated that HIF prolyl hydroxylases are unlikely to be physiological targets of ROS and that the increase in ROS that is associated with downregulation of Thioredoxin Reductase in hypoxia does not affect HIF-1α stabilization. Finally, the protein CHCHD4, which modulates cellular HIF-1α concentrations by promoting mitochondrial electron transport chain activity, has been proposed to exert its regulatory effect by affecting cellular oxygen availability. These reports are consistent with the hypothesis that mitochondria play a critical role in the regulation of HIF-1α by controlling intracellular oxygen concentrations.
Christa Lykke Christensen: Visuelle f lelser - en unders gelse af unges billedoplevelser
Ingunn Hagen
MedieKultur : Journal of Media and Communication Research , 2004,
Abstract:
A constru o do sentido simbiótico entre o Jornal Nacional e William Bonner
Hagen, Sean
Sess?es do Imaginário , 2007,
Abstract: A simbiose na constru o da imagem do Jornal Nacional e do apresentador e editor-chefe William Bonner é o centro desse artigo. Esse movimento desvela uma a o sutil na constru o do mito da excelência profissional, engendrado por jornalistas da imprensa diária, de revistas e sites de informa o. Através de pressupostos da análise do discurso, ressalta-se como a linguagem consegue acionar estruturas míticas na constru o da notícia, abrindo espa o para a subjetiva o nos processos jornalísticos. The symbiosis in the construction of two images – “Jornal Nacional” and its newscaster and editor William Bonner – is the center of this article. This movement reveals a subtle action in the construction of professional excellence myth, produced by newspapers, magazines and information sites journalists. Using discourse analyses principles, we accent how the language operates mythical structures on news production, creating space to subjectivism in journalistic processes.
The myth of perfection: the image of TV-Globo newscasters
Sean Hagen
Brazilian Journalism Research , 2005,
Abstract: The focus of this article is on the mythical image of perfection of the newscasters of the Jornal Nacional – Globo Television Network – constructed by the Brazilian media. Both as soft as well as hard news in magazines, newspapers and information sites, Fátima Bernardes and William Bonner are structured as a couple completely ful lled in the profession, in love and in family relationships. This reading is possible due to the overlapping of journalism and mythical thought. Using discourse analysis concepts as a support, we have analyzed 168 texts between 1998 and 2004, pointing out how the media have constructed this image and what meanings they have mobilized on attributing to the couple a special place in the pantheon of mass culture celebrities. Three distinct formations stand out: a) love, fame and beauty; b) talent and professional success; c) family and morals. More than just journalists, the newscasters are portrayed as stars with impeccable morals, di erent from the vulgar celebrities present in the current media.
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