Academic literature on the topic 'Natural history, gambia'
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Journal articles on the topic "Natural history, gambia"
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Fink, Lyndsay. "The Natural History of Mt. Gambia-Brett Mitchell." Ballarat Naturalist (1990:May) (May 1990): 4–5. http://dx.doi.org/10.5962/p.384037.
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Burton, Matthew J., Richard J. C. Bowman, Hannah Faal, Esther A. N. Aryee, Usman N. Ikumapayi, Neal D. E. Alexander, Richard A. Adegbola, et al. "The Long-Term Natural History of Trachomatous Trichiasis in The Gambia." Investigative Opthalmology & Visual Science 47, no. 3 (March 1, 2006): 847. http://dx.doi.org/10.1167/iovs.05-0714.
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Bowman, R. "Natural history of trachomatous scarring in the Gambia Results of a 12-year longitudinal follow-up." Ophthalmology 108, no. 12 (December 2001): 2219–24. http://dx.doi.org/10.1016/s0161-6420(01)00645-5.
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Shimakawa, Yusuke, Maud Lemoine, Harr Freeya Njai, Christian Bottomley, Gibril Ndow, Robert D. Goldin, Abdoulie Jatta, et al. "Natural history of chronic HBV infection in West Africa: a longitudinal population-based study from The Gambia." Gut 65, no. 12 (July 16, 2015): 2007–16. http://dx.doi.org/10.1136/gutjnl-2015-309892.
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Shimakawa, Y., M. Lemoine, C. Bottomley, H. Freeya Njai, G. Ndow, R. Wegmuller, S. E. Moore, et al. "P0598 : Natural history of chronic hepatitis B infection in The Gambia, West Africa: A longitudinal population-based study." Journal of Hepatology 62 (April 2015): S540—S541. http://dx.doi.org/10.1016/s0168-8278(15)30804-7.
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Barlow, Clive R., Richard P. Reading, Sidney Shema, and Glyn Maude. "Homogeneity in cranial biometrics and bill morphology is verified by measurements from The Gambia, Botswana and Kenya in the case of the putative sub-species of the highly commensal Hooded Vulture Necrosyrtes monachus monachus and non-commensal Necrosyrte." Vulture News 78 (February 9, 2021): 1–10. http://dx.doi.org/10.4314/vulnew.v78i1.1.
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We present biometrical data assembled from a combined total of 37 complete and partially cleaned skulls and feathered heads for the two putative subspecies of Hooded Vulture Necrosyrtes monachus monachus and N. m. pileatus (which Mundy et al. (1992) credibly argue should be N. m. carunculatus). We report on mostly insignificant variation in measurements taken from across three regions of the Hooded Vulture range. For N. m. pileatus (n = 22) the measurements are assembled from 13 live birds captured, tagged and released in Botswana between 2014-2017, seven museum specimens held in The National Museums of Kenya collected during 1913-1950, and two as described below. We compare with N. m. monachus (n = 14) where we measured eight specimens produced by road traffic accidents in The Gambia 2002-2019 of which seven are cleaned bare skulls and one a feathered study skin. We also measured six feathered heads and three skulls from several different countries in Africa, collected during 1832-1929 (n = 6 monachus, 2 pileatus, and 1 unknown) and held at the Natural History Museum, Tring, UK. Cranial materials for Hooded Vulture are scarce in world museums and the Gambian sample consisting of seven cleaned skulls represents the largest known number for a single country. Different populations across the regions vary considerably in both feeding habits and home ranges. We hypothesised that different foraging ecologies may have led to adaptation in bill morphology. Presented here for the first time are a series of skull morphometrics which test for variation in cranial biometrics and bill morphology from across the range of the Hooded Vulture. The Gambian bird has been DNA sequenced and a planned genetics study of other populations will resolve the long-standing taxonomic debate.
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COCK, MATTHEW J. W., T. COLIN E. CONGDON, and STEVE C. COLLINS. "Observations on the Biology of Afrotropical Hesperiidae (Lepidoptera). Part 8. Hesperiinae incertae sedis: Dracaena Feeders." Zootaxa 3985, no. 3 (July 13, 2015): 301–48. http://dx.doi.org/10.11646/zootaxa.3985.3.1.
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The Afrotropical genera Gamia and Artitropa are only known to feed on species of Dracaena (Asparagaceae), and together with Leona lissa Evans, which may require a new genus, they are the only Afrotropical Hesperiidae that feed on this unusual host genus. We present partial life histories of two species of Gamia, 22 taxa of Artitropa (of at least 12 species, and including several undescribed taxa), and notes on the life history of L. lissa. Based on life history information, Gamia and Artitropa are considered likely to form a monophyletic group, probably most closely related to some of the palm-feeding genera currently placed incertae sedis, but formerly in Evans’ 1937 Ploetzia group of genera. Notes on natural enemies of A. erinnys (Trimen) and A. milleri Evans are included.
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Diallo, Moussa, Ebrima SM Kolley, Abdoulaye Kane Dia, Mary Aigbiremo Oboh, Fatoumata Seck, Jarra Manneh, Abdul Karim Sesay, et al. "Evolution of the Ace-1 and Gste2 Mutations and Their Potential Impact on the Use of Carbamate and Organophosphates in IRS for Controlling Anopheles gambiae s.l., the Major Malaria Mosquito in Senegal." Pathogens 11, no. 9 (September 7, 2022): 1021. http://dx.doi.org/10.3390/pathogens11091021.
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Widespread of insecticide resistance amongst the species of the Anopheles gambiae complex continues to threaten vector control in Senegal. In this study, we investigated the presence and evolution of the Ace-1 and Gste2 resistance genes in natural populations of Anopheles gambiae s.l., the main malaria vector in Senegal. Using historical samples collected from ten sentinel health districts, this study focused on three different years (2013, 2017, and 2018) marking the periods of shift between the main public health insecticides families (pyrethroids, carbamates, organophosphates) used in IRS to track back the evolutionary history of the resistance mutations on the Ace-1 and Gste2 loci. The results revealed the presence of four members of the Anopheles gambiae complex, with the predominance of An. arabiensis followed by An. gambiae, An. coluzzii, and An. gambiae–coluzzii hybrids. The Ace-1 mutation was only detected in An. gambiae and An. gambiae–coluzzii hybrids at low frequencies varying between 0.006 and 0.02, while the Gste2 mutation was found in all the species with a frequency ranging between 0.02 and 0.25. The Ace-1 and Gste2 genes were highly diversified with twenty-two and thirty-one different haplotypes, respectively. The neutrality tests on each gene indicated a negative Tajima’s D, suggesting the abundance of rare alleles. The presence and spread of the Ace-1 and Gste2 resistance mutations represent a serious threat to of the effectiveness and the sustainability of IRS-based interventions using carbamates or organophosphates to manage the widespread pyrethroids resistance in Senegal. These data are of the highest importance to support the NMCP for evidence-based vector control interventions selection and targeting.
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Grassly, Nicholas C., Michael E. Ward, Shirley Ferris, David C. Mabey, and Robin L. Bailey. "The Natural History of Trachoma Infection and Disease in a Gambian Cohort with Frequent Follow-Up." PLoS Neglected Tropical Diseases 2, no. 12 (December 2, 2008): e341. http://dx.doi.org/10.1371/journal.pntd.0000341.
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Mikheev, D. V. "SEA GATE OF THE “SPANISH LAKE”: THE FIRST EXPEDITION OF DE GAMBOA TO THE STRAIT OF MAGELLAN." Вестник Пермского университета. История, no. 4(59) (2022): 18–29. http://dx.doi.org/10.17072/2219-3111-2022-4-18-29.
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The article analyzes the preparation and the course of the First expedition to the Strait of Magellan by Pedro Sarmiento de Gamboa, one of the most prominent Spanish navigators, scientists and humanists of the 16th century. The interest of the Spanish discoverers in the Strait arouse immediately after Magellan's circumnavigation, but for more than half a century this area remained a frontier zone of Spanish possessions in the south of the American continent. The Drake's raid revived Spanish projects to explore and colonize the Strait. From a remote, undeveloped frontier area, the Strait turned into one of the main sea gates to the “Spanish Lake”, as the Spaniards themselves called the Pacific Ocean. The idea to prepare an expedition belonged to the Viceroy of Peru, Don Francisco de Toledo. He prepared the instructions and chose de Gamboa from among his subordinates as the general of the expedition. All the instructions of the expedition demonstrate the precise elaboration of all the details of the military and scientific research work necessary for the future colonization of the region. Despite the difficulties of the journey, the first expedition to the Strait can be considered de Gamboa's most successful venture. Following the main orders of the instructions, de Gamboa was able to complete the main tasks of the expedition. The paths to the strait were mapped, its Pacific and Atlantic estuaries were explored, its natural and geographical features were determined, contacts were established with the indigenous population, and the place of the future settlement was outlined. However, noticeable exaggerations in the descriptions of the region's natural resources, the mild climate and its dense population will contribute to the failure of the second larger expedition to the Strait.
Dissertations / Theses on the topic "Natural history, gambia"
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Jaffar, Shabbar. "The natural history of HIV-1, HIV-2 and dual infections in sub-Saharan Africa." Thesis, London School of Hygiene and Tropical Medicine (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248400.
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Baeshen, Rowaidh. "Effects of genetic and environmental factors on reproductive success in the malaria mosquito Anopheles gambiae Sensu Stricto." Thesis, Keele University, 2013. http://eprints.keele.ac.uk/604/.
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Anopheles gambiae is a major vector of malaria in sub-Saharan Africa. Given the widespread emergence of pesticide resistance in Anopheles gambiae populations, vector control programs involving the release of sterile males or genetically-modified male mosquitoes designed to diminish malaria transmission are eliciting renewed interest. The success of such mosquito release projects depends on the ability of released males to effectively mate and transfer sperm to wild females. Here, firstly we investigated the interactive effect of the environmental factor hydric stress and adult mosquito phenotypic quality on male and female reproductive success. Secondly, we studied the impact of colonization and genetic modification on potential correlates of reproductive success by comparing sperm quality and sexual organs in the wild strains with transgenic and colonized strains. We then experimentally tested for the potential effects of inbreeding depression on reproductive traits by creating hybrid males from inbred colonized strains. The quality of these 'Super males' was assessed by comparing sperm quality, testes and accessory gland sizes, and estimating the quantity of Plugin and Transglutaminase proteins in their accessory glands. Finally, we assessed the reproductive performance of Super males by estimating the amount of accessory gland protein transferred to females after overnight mating and estimating female fecundity and number of larvae produced. The results underline the importance of female phenotypic quality as determinant of mosquito reproductive success. Inbreeding associated with the colonization and/or genetic modification processes strongly affects sperm length. In contrast, offspring of field-collected females strain have smaller testes and larger accessory glands than older colonized strains. Super males had a good sperm quality. Importantly, the present study suggests that Super males could represent a way to improve male’s reproductive quality under laboratory conditions.
Books on the topic "Natural history, gambia"
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Ventocilla, Jorge. Gamboa: Una guía para su patrimonio natural y cultural. Panama: Instituto Smithsonian de Investigaciones Tropicales, 2010.
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Rees, Martin J. Global Catastrophic Risks. Edited by Nick Bostrom and Milan M. Cirkovic. Oxford University Press, 2008. http://dx.doi.org/10.1093/oso/9780198570509.001.0001.
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A global catastrophic risk is one with the potential to wreak death and destruction on a global scale. In human history, wars and plagues have done so on more than one occasion, and misguided ideologies and totalitarian regimes have darkened an entire era or a region. Advances in technology are adding dangers of a new kind. It could happen again. In Global Catastrophic Risks 25 leading experts look at the gravest risks facing humanity in the 21st century, including asteroid impacts, gamma-ray bursts, Earth-based natural catastrophes, nuclear war, terrorism, global warming, biological weapons, totalitarianism, advanced nanotechnology, general artificial intelligence, and social collapse. The book also addresses over-arching issues - policy responses and methods for predicting and managing catastrophes. This is invaluable reading for anyone interested in the big issues of our time; for students focusing on science, society, technology, and public policy; and for academics, policy-makers, and professionals working in these acutely important fields.
Book chapters on the topic "Natural history, gambia"
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Schuster, John. "Le Monde as a System of Natural Philosophy and Gambit in the Field." In Studies in History and Philosophy of Science, 525–41. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-4746-3_11.
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Nakagawa, Hitoshi. "History of mutation breeding and molecular research using induced mutations in Japan." In Mutation breeding, genetic diversity and crop adaptation to climate change, 24–39. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0003.
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Abstract Following the construction of the Gamma Field at the Institute of Radiation Breeding in 1960, mutation breeding was accelerated in Japan. The facility is used, with a radiation dose up to 2 Gy/day (ca. 300,000 times that of natural background), to induce mutations at a higher frequency than occurs in nature. There have been 318 direct- use mutant cultivars representing 79 species generated through irradiation of gamma-rays, X-rays, ion beams and chemicals and somaclonal variation. Approximately 79% of these direct-use cultivars were induced by radiation. There have been 375 indirect-use mutant cultivars, including 332 rice, of which 162 cultivars (48.8%) were derived from the semi-dwarf mutant cv. 'Reimei'. The economic impact of these mutant cultivars, primarily of rice and soybean, is very large. Some useful mutations are discussed for rice, such as low digestible protein content, low amylose content, giant embryo and non-shattering. Useful mutations in soybean such as radiosensitivity, fatty acid composition and super-nodulation have been identified. Japanese pear and apple resistant to Alternaria disease have also been identified. The achievements of biological research such as characterization and determination of deletion size generated by gamma-rays, the effect of deletion size and the location, and a mechanism of dominant mutation induction are identified. Similarly, genetic studies on mutations generated through the use of gamma-ray induced mutations, such as phytochrome response, aluminium tolerance, stay-green (Mendel's gene) and epicuticular wax have also been conducted. Mutation breeding is a very useful technology for isolating genes and for elucidating gene functions and metabolic pathways in various crops.
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Cenzato, Marco, Davide Boeris, Maurizio Piparo, Alessia Fratianni, Maria Angela Piano, Flavia Dones, Francesco M. Crisà, and Giuseppe D’Aliberti. "Complications in AVM Surgery." In Acta Neurochirurgica Supplement, 77–81. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-63453-7_11.
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AbstractIn AVM surgery perioperative complications can arise and can have serious perioperative consequences. Surgically related complications in AVM treatment, in many cases, can be avoided by paying attention to details:1. Careful selection of the patient: - addressing a patient with eloquent AVM to Gamma Knife treatment - preoperative treatment with selective embolization of the accessible deep feeders - preoperative gamma knife or embolize those patient with an over-expressed venous pattern2. Meticulous coagulation of deep medullary feeders: - Using dirty coagulation - Using dry non-stick coagulation - Using micro clips - Using laser - Reaching the choroidal vessel in the ventricle when possible - Avoiding occlusive coagulation with hemostatic agents3. Check and avoiding any residual of the AVM4. Keep the patient under pressure control during postoperative periodFulfilling these steps contributes to reduce complications in this difficult surgery, leading to a safer treatment that compares favorably with natural history of brain arteriovenous malformations.
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"Learning, behaviour programs, and higher-level rules in nest construction of Polistes." In Natural History and Evolution of Paper-Wasps, edited by John W. Wenzel, 58–74. Oxford University PressOxford, 1996. http://dx.doi.org/10.1093/oso/9780198549475.003.0003.
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Abstract Many students of social insects view the nest as little more than a substrate upon which social life unfolds. Nest architecture is generally neglected in favour of studies that ask the perennially more fashionable questions, often variations and derivatives of the query 'who laid the eggs?' In Polistes, specific issues of genetical relatedness and reproduction capture the greatest attention (Reeve 1991). These studies have inspired several general theories of social evolution and provided tests of others, but studies of nest architecture of Polistes remain relatively obscure. Yet, characteristics of the paper nest address many fundamental topics, such as the evolution of complex chains of behaviours (Downing and Jeanne 1987, 1988, 1990; Wenzel 1993), the division of labour (Jeanne 1986a), the self-organization of construction behaviour (Deneubourg et al. 1992; Karsai and Penzes 1993), and kin recognition (Gamboa et al. 1986b; Espelie et al. 1990; Singer and Espelie 1992).
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Lyman, R. Lee. "Early History of Archaeology Graphs." In Graphing Culture Change in North American Archaeology, 72–101. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198871156.003.0005.
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The earliest archaeological spindle graph was published in 1883 by natural historian and avocational archaeologist Charles C. Abbott. Evidence that he obtained the idea from paleontology, which first published spindle graphs in the 1830s and 1840s, is circumstantial at best, and differences in graph styles weigh against such borrowing. Several spindle graphs published in the 1890s and early 1900s by archaeologist William Henry Holmes either depict his views on inevitable progressive evolution—a theory rapidly falling from anthropological favor—or were so speculative as to likely have had little influence on the discipline. During the first couple decades of the twentieth century, physicist/geographer/anthropologist Franz Boas (often referred to as the father of anthropology) published numerous line graphs of quantitative data. He influenced archaeologists Leslie Spier and Manual Gamio who used line graphs to display temporally varying frequencies of artifacts. About the same time, the wife and husband team of Madeleine Kidder and Alfred V. Kidder published several line graphs of relative frequencies of pottery types against stratigraphic provenience, seemingly largely as a result of Madeleine’s influence because Alfred never again published such a graph and instead favored phyletic seriation graphs of a type reminiscent of Sir William Flinders Petrie’s sequence dating graphs from the turn of the century.
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Fisher, David. "The Strange Case of Helium and the Nuclear Atom." In Much Ado about (Practically) Nothing. Oxford University Press, 2010. http://dx.doi.org/10.1093/oso/9780195393965.003.0010.
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It is often taken as a matter of established fact that the difference between a good scientist and a great scientist is the ability to distinguish in advance which problems are going to be the important ones. I think this belief is a reflection of the fact that history is written by the winners: Professor X chooses a problem and with much hard work solves it, but it turns out not to have important consequences, so it and he are forgotten; Professor Y does the same, but this time the result spurs further work or even opens new and unforeseeable regions of science, so he naturally feels that his “intuition” was correct. But how do you distinguish his intuition from a lucky guess? I suggest that a study of the history of science tells us that luck plays a significant part. Consider, for example, Lord Rutherford’s discovery of the nuclear atom—perhaps the most important experimental discovery of the twentieth century, in that it led to quantum theory and the whole of nuclear physics. To set the stage: By the first few years of the twentieth century it had been determined that there were three kinds of radioactive emissions, termed alpha, beta, and gamma rays. The gamma rays were electromagnetic in nature, the beta rays were electrons, and Rutherford had just shown that the alpha rays were in fact helium; or rather, as he put it, the alpha rays were a stream of particles zipping along at roughly 10,000 miles per second which, after they slowed down and lost their electric charge, became helium atoms. (He didn’t realize at the time that they “lost” their positive electric charge by picking up negatively charged electrons.) What next? Well, the natural thing to do was to see how these radioactive emissions interacted with matter. This had already been done with the beta and gamma radiations: a stream of these radiations had been directed at various targets, and such parameters as their depth of penetration and ionizing capabilities had been measured, with no particular insights gained (an example of Professor X’s work).
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Bloom, Joshua S. "Gamma-Ray Bursts as Probes of the Universe." In What Are Gamma-Ray Bursts? Princeton University Press, 2011. http://dx.doi.org/10.23943/princeton/9780691145570.003.0006.
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This chapter focuses on how gamma-ray bursts (GRBs) are emerging as unique tools in the study of broad areas of astronomy and physics by virtue of their special properties. The unassailable fact about GRBs that makes them such great probes is that they are fantastically bright and so can be seen to the farthest reaches of the observable Universe. In parallel with the ongoing study of GRB events and progenitors, new lines of inquiry have burgeoned: using GRBs as unique probes of the Universe in ways that are almost completely divorced from the nature of GRBs themselves. Topics discussed include studies of gas, dust, and galaxies; the history of star formation; measuring reionization and the first objects in the universe; neutrinos, gravitational waves, and cosmic rays; quantum gravity and the expansion of the universe; and the future of GRBs.
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Kammen, Michael. "A Utilitarian Culture and The Uses of Leisure." In Colonial New York, 242–77. Oxford University PressNew York, NY, 1996. http://dx.doi.org/10.1093/oso/9780195107791.003.0010.
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Abstract At first glance, provincial New York may seem to have been what H. L. Mencken once called the South, a “Sahara of the Bozart,” that is, a cultural desert. In 1688 Charles Lodwick was requested to provide the Royal Society with “a compendious Natural History of that Countrey.” He apologized for taking four years to do the job but explained in 1692 that “where Masters of Ships are ye chiefest Mathematicians & ye Natives [the chief] Geographers, with such tools you must not expect a good Fabrick. . . .” James Petiver, a prominent Fellow of the Royal Society, tried for three years (1692-95) to establish a scientific correspondence with Dr. Alexander Innis at Boscobell House, near Hempstead, Long Island; but Innis never replied. Petiver tried again with one Robert Gamble in 1713–14; yet, once again, silence from New York. Three decades later, in 1742, Cadwallader Colden expressed his appreciation to a London correspondent for the opportunity “to communicate some thoughts in natural philosophy which have remained many years with me undigested, for we scarcely have a man in this country that takes any pleasure in such kinds of speculations.”
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Goldsmith, Mike. "6. Electromagnetic waves." In Waves: A Very Short Introduction, 70–99. Oxford University Press, 2018. http://dx.doi.org/10.1093/actrade/9780198803782.003.0006.
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‘Electromagnetic waves’ considers the history of the scientific investigation into the electromagnetic spectrum, including Einstein’s insight into the quantized nature of electromagnetic radiation. It explains that the only difference between light, radio waves, and all the other forms of electromagnetic radiation is the length of the fictitious-but-convenient waves or, equivalently, the energy of the photons involved. These different energies lead to different mechanisms for the formation and absorption of the different kinds of radiation, and it is this which gives rise to their different behaviours. Radio waves, microwaves, infrared radiation, light, ultraviolet light, X-rays, and gamma rays are all discussed.
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Davis, Paul K. "Ipsus Spring 310 B.C." In 100 Decisive Battles, 34–38. Oxford University PressNew York, NY, 2001. http://dx.doi.org/10.1093/oso/9780195143669.003.0009.
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Abstract Legend has it that, when Alexander the Great lay dying in June 323 B.C., one of his subordinates asked who was to inherit his empire. The response was: “the strongest.” The largest empire the world had yet known, stretching from Greece to the borders of India, could in reality only be held together by a man of Alexander’s vision, and few men in history rise anywhere near that level. Alexander’s only natural heir was an infant who, along with his mother Roxanne, was soon killed. Thus began the struggle to determine which of Alexander’s subordinates could prove himself strongest. Fairly quickly four men rose to serious contention. In Egypt, Ptolemy was Alexander’s governor. He had the immense wealth of Egypt upon which to draw (vital for hiring Macedonian troops, the core of any successful army). He also had Alexander’s body, which he acquired through some trickery in order to bury it at the shrine of Amon where Alexander was supposedly named a god. Unfortunately for him, Ptolemy lacked the bold temperament necessary to gamble for really high stakes. In Macedon itself was Antipacer, left behind to maintain control over the homeland and Greece during Alexander’s campaigns. Antipater soon died, however, and was succeeded by his son Cassander.
Conference papers on the topic "Natural history, gambia"
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Alnasser, Hassan Basim, Ugochukwu Maria Okeke, Zhiheng Zhang, Ronnie Van Der Veen, Sadaf Shoukatali Chishti, and Saken Umirshin. "Efficient and Reliable Multilateral Coiled Tubing Intervention Technique for Acid Stimulation: A Case History in the Middle East." In SPE/ICoTA Well Intervention Conference and Exhibition. SPE, 2023. http://dx.doi.org/10.2118/212921-ms.
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Abstract In recent years, multilateral wells have become more predominant enabling either improved recovery or injectivity depending on the well type. The process of timely accessing the correct lateral with coiled tubing (CT) is still one of the greatest challenges relative to the well intervention. This paper presents a case history in which a flawless 2.375-in CT intervention was performed to stimulate laterals with a proprietary multilateral entry bottom hole assembly (BHA) that steered the CT efficiently into the laterals. The injector well has a natural and un-natural lateral, both of which required stimulation. A proprietary hydraulic multilateral entry tool was selected for the job which reliably locates and enters multiple lateral junctions in a single run. The special working mechanism of the tool circumvents any need for an electrical control or steering system. Along with this tool, a casing collar locator (CCL) was incorporated into the BHA, powered by a proprietary CT conductor telemetry system. Real time data enabled confirmation relative to access into the correct lateral to save time without the need to tag the bottom. A gamma ray (GR) sub can also be incorporated into the BHA to correlate depth where needed. A major challenge for multilateral intervention is time on location. The multilateral entry tool searches for the lateral by rotating 360° until it reaches the desired kick off angle which is confirmed by a surface pressure indication signifying that the correct lateral has been located. The simple yet effective operational mechanism of the multilateral tool allows each lateral to be found and entered in less than 30 minutes once it is positioned at the window. Depth correlation is confirmed with use of either the CCL or GR subs or a combination of the two and the multilateral entry tool is resettable easily by pressurizing, which enables any number of laterals to be located & stimulated. The job was completed safely as per program with more than 4,000 bbl of acid pumped to stimulate both the laterals. The entire operation was conducted efficiently, flawlessly, and post injectivity results of the stimulation resulted in significant incremental injection drainage capability. This combination of BHA's options and the efficient mechanism of the multilateral entry tool to find and enter multiple laterals quickly and reset without the need to pull out of hole, enables the Operator to intervene in any number of branches of a multilateral well in a timely and efficient manner. This is a very important case history for other complex multilateral wells in the region which could benefit from this technology and approach
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Hwang, Irene. "Pivotal constructions of unseen events: Building the American dream." In 3rd Valencia International Biennial of Research in Architecture, VIBRArch. València: Editorial Universitat Politècnica de València, 2022. http://dx.doi.org/10.4995/vibrarch2022.2022.15200.
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Is important that architecture is the product of more than the aesthetic concerns of the architect and the practical concerns of the client. It straddles two realms: that of the fine arts and that of the highly practical and utilitarian. In its dual nature, architecture is most often cast as a high art; the outcomes of architectural thinking and making are celebrated, analyzed, and documented for their aesthetic significance as art objects. Architecture’s impact as a service, being practical and useful, are deemed less worthy by both the discipline and profession. Pivotal Constructions of Unseen Events reconstitutes a new reading of American history from 1871-2020, a period marked by tremendous national growth and building, alongside the rise of new shared ideas, practices, and customs that have shaped—and continue to shape—the structures of American society alongside the structures of its built environment.Through the construction of five narratives for five buildings of architectural origin, this research examines the social, technological, material, and economic forces that led to their emergence and construction, as well as the outcomes that arose in society afterward. Pivotal Constructions demonstrates—through the close reading of buildings—how to understand architecture as historical event rather than historical artifact. Whereby architecture’s historical significance is not solely as a static object (or artifact), but rather as something that happened and happens (an event), transforming and shaping history in unexpected and significant ways. This approach gathers and reassembles evidence of architecture’s historical significance, elements hence claimed by other narratives, absorbed by other disciplines, and told by other actors. This method of re-constructing architectural history, is meant to recapture a fuller gamut of architecture’s impact on and in society.For VIBRArch 2022, this author presents one of these narratives: “Building the American Dream”, the history of how the arrival in 1908 of the Gamble House (Greene and Greene Architects) played a part in the genesis of the single-family, detached house, which has become a potent and defining symbol of American values and morals.
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Koray, Abdul-Muaizz, Dung Bui, William Ampomah, Emmanuel Appiah-Kubi, and Joshua Klumpenhower. "Improving Subsurface Characterization Utilizing Machine Learning Techniques." In SPE Western Regional Meeting. SPE, 2023. http://dx.doi.org/10.2118/212952-ms.
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Abstract The objective of this paper is to present a framework that applies machine learning to reservoir characterization. Machine learning applications in the oil and gas industry is rapidly becoming popular and in recent years has been utilized for the characterization of various reservoirs. Conventional reservoir characterization employs core data measurements and local correlations between porosity and permeability as input data for reservoir property modeling. However, a strong correlation between porosity and permeability as well as reliable core measurements are not always available. The proposed approach uses both well logs and core data to construct different models to predict permeability using three distinct methods including a parametric, non-parametric, and machine learning technique. The parametric method employed the known relationship between porosity and the natural log of permeability. The non-parametric regression method utilized the alternating conditional expectation (ACE) algorithm. The third approach involved machine learning workflow implemented within a commercial software. The reservoir was first classified into distinct hydraulic flow units using the flow zone indicator (FZI) approach and k-means clustering. Permeability was then predicted using a supervised machine-learning framework. A field case study was then utilized to ascertain the effectiveness of these approaches by validating the model with data from one of the wells. The results of these three approaches were compared using the mean absolute error (MAE) and mean squared error (MSE) values in the validation process. An examination of the error calculated found the support vector machine (SVM) and linear regression algorithms in characterizing the upper reservoir region and the SVM for the lower reservoir characterization yielding the best results when using the machine learning approach thus, yielding the least error as compared to the other two approaches. Additional validation was performed by comparing different models based on permeability fields through numerical model calibration to historical data. It was found that machine learning-based permeability had the least error compared to calibration data prior to the history matching process. The investigated reservoir consists of two distinct productive oil zones separated by an impermeable shale. There are 15 existing wells that have been producing from both the upper and lower zones since 1997. Using machine learning permeability-based model, the history matching process was conducted successfully to match both observed production data and pressure data of 15 wells with less than 10% global deviation. This study presents the feasibility of applying several different approaches in predicting permeability based on gamma ray, bulk density, and deep resistivity logs. The machine learning approach proves its high potential and readiness in supporting reservoir characterization and history matching compared to the other approaches.
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Gryaznov, Andrey, David Wiprut, Pramit Basu, Tural Jafarov, Michael Reese, and Johannes Vossen. "1D Geomechanical Modelling of a Complex Naturally Fractured Volcanoclastic Reservoir, Republic of Georgia." In International Petroleum Technology Conference. IPTC, 2022. http://dx.doi.org/10.2523/iptc-22248-ms.
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Abstract The objectives of this study were to deliver a pre-drill and real-time (RT) geomechanical model and wellbore stability analysis for the planned horizontal well within license Block XIb, Republic of Georgia. The main target is fractured tight volcanoclastic Middle Eocene (ME) formation. Pre-drill and RT Wellbore stability analyses were performed enabling safe mud weight requirements and mud weight sensitivity to inclination for the planned wellbore, as this area is significantly understudied in terms of rock properties, pore pressure behaviour and geomechanics. The model study was based on the drilling experience of the offset well, drilled a mile away and containing many data sets: wireline logs and borehole images, FIT/LOT, pressure measurements, drilling experience and cuttings, well construction and from the current well containing basic LWD gamma ray and mud log. The main problem areas were defined based on the model. Pore pressure drove many of the observed challenges, including the Maikop overpressured shales forming significant breakout zones, and the overpressured Upper Eocene sand and reactive Navtlugi shales zone experiencing many tight hole events in the offset well. Pore Pressure was later updated for the current well based on the drilling exponent (Dxc) calibrated with mud gas data as a part of RT Geomechanics study. The natural fracture behaviour of ME was carefully studied to identify potentially critically stressed fractures and near-wellbore fracture slip. The models examined breakout during underbalanced drilling as well as optimal well azimuths to minimize potential fluid losses in open fractures during drilling and avoid water cut during production. The study found that the originally planned mud weight was too risky and has to be increased in the overburden formations to avoid massive breakouts, as experienced in the offset well. While crossing target ME fractured volcanoclastic slightly underbalanced drilling may be possible. The pre-drill fracture stability study successfully confirmed its reliability during operations and allowed confidently make RT decisions. As a result, concern for losses lowered while moving the azimuth from Shmin to SHmax direction and mud weight (MW) could be raised confidently up to required level. The conducted studies, despite many challenges and data uncertainties, significantly clarified potential drilling risks within the license block area, which was understudied in terms of geomechanics in past years. Additional value was provided to future drilling programs as well as highlighting data gaps and pathways for further geomechanical model improvement and uncertainty mitigation. The model is the first valuable step in developing regional geomechanical understanding. Increased MW helped to avoid major tight hole events, detailed natural fractures analysis helped to select wellbore azimuth optimal to avoid fluid losses. As a result, rate of penetration (ROP) increased 2.3 times compared to previously drilled wells and the well became the first in the field history drilled with no fluid and cement losses. Pre-drill geomechanical model helped to develop the program suitable for safe drilling and later its success was proven through RT geomechanics support. RT geomechanical model update together with caving analysis demonstrated how it plays key role together with pre-drill geomechanical modelling in the successfully well delivery.
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Vandergraaf, Tjalle T., Gudrat G. Mamedov, Mahammadali A. Ramazanov, Jalal A. Naghiyev, Afat A. Mehdiyeva, and Nazim A. Huseynov. "Determination of the Radionuclide Contamination on the Absheron Peninsula in Azerbaijan." In ASME 2011 14th International Conference on Environmental Remediation and Radioactive Waste Management. ASMEDC, 2011. http://dx.doi.org/10.1115/icem2011-59177.
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Much of Azerbaijan’s Absheron Peninsula is contaminated by natural U-series and Th-series radionuclides, released in the production of oil and gas and, to a lesser extent, by anthropogenic radionuclides, including Sr-90 and Cs-137, from local industrial activities and trans-border transport. The region contains a large number of pipelines and artificial lagoons that have been used to retain excess groundwater and oil residues. In spite of the long history of the oil and gas industry, radioecological investigations have not been carried out until recently. The purpose of this project is to determine the extent of radionuclide contamination in the Absheron Peninsula using a combination of radiation field measurements and laboratory analyses of selected samples, focusing on ten routes in the vicinity of Baku. The routes were selected as most likely to have become contaminated over time. Soil samples, taken from surface and to a depth of 1 m, aqueous samples from surface waters and marshes, and aqueous and sediment lagoons that showed elevated dosimetry readings, were prepared for gamma spectrometric analysis. Control samples were taken from non-contaminated areas. Samples of air and surface waters were analyzed for Rn-220 and Rn-222. The data will then be used to assess the potential impact of the contamination on the local population. A total slightly 4000 dosimetric readings were taken during the course of this investigation. Of these, 1366 (34%) exceeded 5.4 μR/h. This level is two standard deviations above the mean of the least contaminated route, the 79-km Baku-Guba route. Along the routes Baku-Shemakha and Baku-Guba where no oil and gas activity had taken place, radiation levels of 5.1 ± 1.5 and 4.2 ± 0.6 μR/h, respectively, were obtained. The readings for the route Baku-Guba were then used as representing negligible contamination to which the readings of the other sites were compared. In contrast, along the routes Baku-Lokbatan and Baku-Surakhani, that have seen oil- and gas-related activity, radiation levels were sometimes two or three orders of magnitude higher. The most highly contaminated sites were those of two abandoned iodine recovery facilities along the route Baku-Surakhani, the Ramani and Surakhani sites where readings up to 1450 μR/h were obtained. The contamination is due mainly to uranium and thorium in the formation water associated with the oil and gas. Radon measurements did not exceed 20 Bq/m3.
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Cebrián Fernández, Rosario, Raúl Carral Fernández, and Román Esteban Díez. "Arqueología reconstructiva digital para el visitante de Segobriga. La experiencia POLIRURAL en su Parque Arqueológico." In Congreso CIMED - II Congreso Internacional de Museos y Estrategias Digitales. Valencia: Editorial Universitat Politècnica de València, 2022. http://dx.doi.org/10.4995/cimed22.2022.15351.
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La ocupación del yacimiento arqueológico de Segobriga se extiende en el cerro de Cabeza de Griego (Saelices, Cuenca) entre la Segunda Edad del Hierro y la Época Medieval. Para reconstruir su historia a lo largo de estos siglos contamos con los datos estratigráficos aportados por las excavaciones realizadas desde los años 50 del siglo XX hasta la actualidad, pero también con la información manuscrita referente a los hallazgos antiguos y trabajos arqueológicos de los siglos XVIII y XIX. Al mismo tiempo, los estudios vinculados a la epigrafía, la arquitectura, decoración arquitectónica y esculturas han permitido plantear hipótesis interpretativas de restitución de la ciudad altoimperial y tardoantigua. La apertura pública del Parque Arqueológico de Segóbriga en 2002 creó las primeras imágenes virtuales para facilitar al visitante su interpretación en su propio entorno histórico y natural. Desde 2018, en el Parque se desarrolla un proyecto de divulgación científica a través de la implementación de herramientas digitales, que permiten a su visitante interpretar los restos arqueológicos. El proyecto POLIRURAL está implementado las TIC en la visita, desarrollando diferentes herramientas a través de nuevas tecnologías innovadoras, que ayudan, junto con una estrategia de interpretación adecuada, a la transferencia del conocimiento científico del yacimiento al gran público. A día de hoy, el proyecto ha incorporado una amplia gama de contenidos que versan sobre la difusión del patrimonio y la naturaleza mediante numerosas técnicas punteras como la Realidad Aumentada, la fotogrametría, reconstrucciones virtuales, recreaciones 3D, avisos sonoros, reconocimiento de imágenes, entre otras, que reconstruyen con exactitud diversos espacios excavados, sobre el entorno real y sin perder la percepción de este. Así, a través del desarrollo de nuevos recursos y herramientas virtuales se facilita a los diferentes tipos de usuarios el acceso al conocimiento arqueológico del yacimiento, esencia de su Parque. El proyecto ha conseguido poner en valor la investigación científica, adaptándola a las necesidades del visitante a través de la gestión eficiente de los recursos disponibles. Participa un equipo multidisciplinar que cuenta con una amplia experiencia previa en patrimonio arqueológico, creación de contenidos interpretativos y divulgación didáctica, así como en proyectos de investigación y desarrollo. POLIRURAL, es un proyecto de Desarrollo Rural Europeo financiado a través de los fondos de Innovación Horizonte 2020. En él participa el Grupo Tragsa en representación de España junto a 16 países europeos.