13 research outputs found
Performance of Delta-hedging strategies in interval models - A robustness study
No full texthedging;volatility;option pricing
Experimental constraints on fluid-rock reactions during incipient serpentinization of harzburgite
No full textAuthor Posting. © The Author(s), 2014. This is the author's version of the work. It is posted here by permission of Mineralogical Society of America for personal use, not for redistribution. The definitive version was published in American Mineralogist 100 (2015): 991-1002, doi:10.2138/am-2015-5112.The exposure of mantle peridotite to water at crustal levels leads to a cascade of interconnected dissolution-precipitation and reduction-oxidation reactions—a process referred to as serpentinization. These reactions have major implications for microbial life through the provision of hydrogen (H2). To simulate incipient serpentinization under well-constrained conditions, we reacted centimeter-sized pieces of uncrushed harzburgite with chemically modified seawater at 300 ºC and 35 MPa for ca. 1.5 yr (13 441 h), monitored changes in fluid chemistry over time, and examined the secondary mineralogy at the termination of the experiment. Approximately 4 mol% of the protolith underwent alteration forming serpentine, accessory magnetite, chlorite, and traces of calcite and heazlewoodite. Alteration textures bear remarkable similarities to those found in partially serpentinized abyssal peridotites. Neither brucite nor talc precipitated during the experiment. Given that the starting material contained ~4 times more olivine than orthopyroxene on a molar basis, mass balance requires that dissolution of orthopyroxene was significantly faster than dissolution of olivine. Coupled mass transfer of dissolved Si, Mg, and H+ between olivine and orthopyroxene reaction fronts was driven by steep activity gradients and facilitated the precipitation of serpentine. Hydrogen was released in significant amounts throughout the entire experiment; however, the H2 release rate decreased with time. Serpentinization consumed water but did not release significant amounts of dissolved species (other than H2) suggesting that incipient hydration reactions involved a volume increase of ~40%. The reduced access of water to fresh olivine surfaces due to filling of fractures and coating of primary minerals with alteration products led to decreased rates of serpentinization and H2 release. While this concept might seem at odds with completely serpentinized seafloor peridotites, reaction-driven fracturing offers an intriguing solution to the seemingly self-limiting nature of serpentinization. Indeed, the reacted sample revealed several textural features diagnostic of incipient reaction-driven fracturing. We conclude that fracturing must have far reaching impacts on the rates of serpentinization and H2 release in peridotite-hosted hydrothermal systems.This study was partially supported by the National Science Foundation (NSF-OCE grants 1059534 to F.K. and S.E.H. and OCE-0927744 To T.M.M.) and the Deep Ocean Exploration Institute at the Woods Hole Oceanographic Institution.2016-04-0
Self-concept, emotions and consumer coping: smoking across Europe.
No full textWhereas much previous research focuses on the ways consumers strive to gain social approval, consumption that may result in social disapproval must be considered. In order to do so, the purpose of this paper is to explore consumers' self-concepts within a risky consumption context, namely smoking. Self-concept discrepancies and the resulting emotions and coping strategies are identified. A qualitative methodology based on 30 focus groups conducted across ten European countries is employed. Findings demonstrate self-concept discrepancies between both the actual self and ought/ideal guiding end states, as well as between the 'I' and social selves. Such discrepancies generate negative emotions and result in emotion-focused coping strategies. In addition, the accuracy of smokers' social self-concepts with reference to the actual perceptions of non-smokers is discussed. Important implications for the design of effective anti-smoking advertising are discussed, based on the findings. It is suggested that counter advertising should encourage dialogue between smokers and non-smokers and that message themes should centre on building the self-efficacy of smokers. The reason why the social context should be an integral part of consumer self-concept research is highlighted. Moreover, the importance of moving beyond merely understanding the existence of self-discrepancies, to focus on the emotions that are generated by these discrepancies and the consequent coping strategies employed to resolve them is identified. As such, the potential contributions that may arise by recognising the intersection between two bodies of literature that are often treated separately, namely, consumer coping and the self-concept, are highlighted
Investigation of extractable organic compounds in deep-sea hydrothermal vent fluids along the Mid-Atlantic Ridge
No full textAuthor Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Geochimica et Cosmochimica Acta 156 (2015): 122-144, doi:10.1016/j.gca.2015.02.022.The possibility that deep-sea hydrothermal vents may contain organic compounds produced by abiotic synthesis or by microbial communities living deep beneath the surface has led to numerous studies of the organic composition of vent fluids. Most of these studies have focused on methane and other light hydrocarbons, while the possible occurrence of more complex organic compounds in the fluids has remained largely unstudied. To address this issue, the presence of higher molecular weight organic compounds in deep-sea hydrothermal fluids was assessed at three sites along the Mid-Atlantic Ridge that span a range of temperatures (51 to >360 °C), fluid compositions, and host-rock lithologies (mafic to ultramafic). Sample were obtained at several sites within the Lucky Strike, Rainbow, and Lost City hydrothermal fields. Three methods were employed to extract organic compounds for analysis, including liquid:liquid extraction, cold trapping on the walls of a coil of titanium tubing, and pumping fluids through cartridges filled with solid phase extraction (SPE) sorbents. The only samples to consistently yield high amounts of extractable organic compounds were the warm (51-91 °C), highly alkaline fluids from Lost City, which contained elevated concentrations of C8, C10, and C12 n-alkanoic acids and, in some cases, trithiolane, hexadecanol, squalene, and cholesterol. Collectively, the C8-C12 acids can account for about 15% of the total dissolved organic carbon in the Lost City fluids. The even-carbon-number predominance of the alkanoic acids indicates a biological origin, but it is unclear whether these compounds are derived from microbial activity occurring within the hydrothermal chimney proximal to the site of fluid discharge or are transported from deeper within the system. Hydrothermal fluids from the Lucky Strike and Rainbow fields were characterized by an overall scarcity of extractable dissolved organic compounds. Trace amounts of aromatic hydrocarbons including phenanthrenes and benzothiophene were the only compounds that could be identified as indigenous components of these fluids. Although hydrocarbons and fatty acids were observed in some samples, those compounds were likely derived from particulate matter or biomass entrained during fluid collection. In addition, extracts of some fluid samples from the Rainbow field were found to contain an unresolved complex mixture (UCM) of organic compounds. This UCM shared some characteristics with organic matter extracted from bottom seawater, suggesting that the organic matter observed in these samples might represent seawater-derived compounds that had persisted, albeit with partial alteration, during circulation through the hydrothermal system. While there is considerable evidence that Rainbow and Lost City vent fluids contain methane and other light hydrocarbons produced through abiotic reduction of inorganic carbon, we found no evidence for more complex organic compounds with an abiotic origin in the same fluids.This research was supported by the NSF Ocean Sciences directorate through grants MGG-OCE 0550800 to T.M.M. and MGG-OCE 0549829 to J.S.S. and C.R.G
The strategic response of full service airlines to the low cost carrier threat and the perception of passengers to each type of carrier
No full textLow cost carriers have changed the competitive dynamics of the short-haul market
forever. They have revolutionised the way of doing business in aviation by adopting a
fresh approach on both strategic and operational issues. Simplicity has become their
universal principle over network airlines and subsequently they have achieved
substantial cost advantages which are passed onto the consumer as lower fares.
Network airlines have found it difficult to reshape their structural barriers and have
been slow to incorporate the components that low cost carriers deemed very
significant in impacting their operating margins. However, a restructuring of their
internal weaknesses should spur initiatives to design long-term strategies to address
those shortcomings. Network airlines rely on producing value-adding and consumerdriven
product differentiation beyond the basics of the low cost carrier product. To
further differentiate themselves network airlines need to focus on: customer
satisfaction; develop long term mutually beneficial relationships with both passengers
and corporations; collaborate with a wide range of bipartisan partners; retain
differentiated flight products that add value; and to incorporate strategies that other
network carriers deemed paradigmatic. Network carriers should resist reducing costs
associated with value-added services and need to become innovative in generating
alternative revenue streams
The use of corporate reputation in the development of brand image strategy in the Taiwanese pharmaceutical industry
No full textThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.This doctoral research aims to investigate the reputation building process of companies and to examine the applicability of western-developed theories about the uses of corporate reputation in a non-western context. It is the first study that synthesises three theories (value creation, strategic resources and corporate communication) to examine the strategic consequences of the uses of corporate reputation.
Corporate reputation is an attribute or a set of attributes ascribed to a firm and inferred from the firm’s past actions. It is the belief of market participants about a firm’s strategic character (Weigelt and Camerer, 1988). Also, corporate reputation is the public’s cumulative judgement of a firm over time (Roberts and Dowling, 2002).
The review of theoretical literature indicates the uses of corporate reputation by business organizations can be theorized along six dominant paradigmatic perspectives: 1-public relations; 2-marketing; 3-management, 4-economic; 5-sociological; 6-finance and accounting. The uses of corporate reputation in these six paradigms are comprehensively discussed. The objective of this study is to establish the use of corporate reputation in the development of brand image strategy. A review of the uses of the concept of corporate reputation is discussed in detail in chapter 2.
The review of the literature also identified a research gap by showing that scarce research has been conducted on how these three main functions (value creation, strategic resources and corporate communication) affect a company’s brand positioning strategy. The following research question thus is proposed: How do (Taiwanese pharmaceutical) companies use their corporate reputation to develop a brand image strategy?
The research hypotheses based on three theories (value-based theory, resource-based theory and integrated marketing communication theory) appear in Chapter 3. The research question is constructed theoretically, and then a conceptual model, which begins with three antecedents of corporate reputation and simultaneously illustrates the outcomes of their use, are discussed.
The construct of the uses of corporate reputation has three dimensions: value creation, strategic resources and corporate communication. Each of these three dimensions includes several items. The items were proposed based on the previous researchers’ summaries and the qualitative interview. The researcher will then depict the proposed research conceptual framework and a number of hypotheses that will be further investigated and tested.
Then the quantative study was completed by providing the data analysis and the results were explained. A multi-stage procedure was involved in this research. First, data examination and screening to prepare for subsequent quantitative analyses and then the descriptive statistics were presented. Second, a reliability test was performed on measurement scales to ensure that they achieve an acceptable level of reliability for further analysis. The resulting solutions were then re-assessed using confirmatory factor analysis. Finally, PLS (Partial Least Squares) was used to test the hypothesized relationships between the research constructs as postulated in the conceptual model, and to assess the overall goodness-of-fit between the proposed model and the collected data set.
The researcher then discusses the validation of the measurement model and the research findings. The findings are then further discussed in terms of the contribution to marketing theory and relevance to marketing managers. Then the items of adapted scales were subjected to several rounds of adjustments and were finally found to possess acceptable measurement properties. Reliability and construct validity tests indicated that all scales satisfied widely accepted criteria such as the minimum reliability of 0.7. The results of scale purification will be discussed. And an evaluation of the research hypotheses and their significance are summarized, the findings of all hypotheses testing will be reviewed and compared with previous research.
According to the research findings, the hypotheses that value creation, as one dimension of corporate reputation, has a positive impact on brand segmentation, brand differentiation and brand positioning are all accepted. The hypotheses that strategic resource, as one dimension of corporate reputation, has a positive impact on brand segmentation and brand differentiation are rejected. However, the hypothesis that strategic resource, as one dimension of corporate reputation, has a positive impact on brand positioning is accepted. The hypotheses that corporate communication, as one dimension of corporate reputation, has a positive impact on brand segmentation and brand differentiation are both accepted. The hypothesis that corporate communication, as one dimension of corporate reputation, has a positive impact on brand positioning is partially supported. Finally, the hypothesis that the (see in Table 5.18) moderating effect of price policy on corporate reputation has a positive impact on brand image strategy is partially but negatively supported.
This thesis makes a significant contribution to the study of corporate reputation of firms in the Taiwanese pharmaceutical industry from the robustness of the qualitative and quantitative data collection
Global, regional, and national age-sex-specific mortality and life expectancy, 1950-2017: A systematic analysis for the Global Burden of Disease Study 2017
No full textBackground: Assessments of age-specifc mortality and life expectancy have been done by the UN Population Division, Department of Economics and Social Afairs (UNPOP), the United States Census Bureau, WHO, and as part of previous iterations of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD). Previous iterations of the GBD used population estimates from UNPOP, which were not derived in a way that was internally consistent with the estimates of the numbers of deaths in the GBD. The present iteration of the GBD, GBD 2017, improves on previous assessments and provides timely estimates of the mortality experience of populations globally. Methods: The GBD uses all available data to produce estimates of mortality rates between 1950 and 2017 for 23 age groups, both sexes, and 918 locations, including 195 countries and territories and subnational locations for 16 countries. Data used include vital registration systems, sample registration systems, household surveys (complete birth histories, summary birth histories, sibling histories), censuses (summary birth histories, household deaths), and Demographic Surveillance Sites. In total, this analysis used 8259 data sources. Estimates of the probability of death between birth and the age of 5 years and between ages 15 and 60 years are generated and then input into a model life table system to produce complete life tables for all locations and years. Fatal discontinuities and mortality due to HIV/AIDS are analysed separately and then incorporated into the estimation. We analyse the relationship between age-specifc mortality and development status using the Socio-demographic Index, a composite measure based on fertility under the age of 25 years, education, and income. There are four main methodological improvements in GBD 2017 compared with GBD 2016: 622 additional data sources have been incorporated; new estimates of population, generated by the GBD study, are used; statistical methods used in diferent components of the analysis have been further standardised and improved; and the analysis has been extended backwards in time by two decades to start in 1950. Findings: Globally, 18·7% (95% uncertainty interval 18·4-19·0) of deaths were registered in 1950 and that proportion has been steadily increasing since, with 58·8% (58·2-59·3) of all deaths being registered in 2015. At the global level, between 1950 and 2017, life expectancy increased from 48·1 years (46·5-49·6) to 70·5 years (70·1-70·8) for men and from 52·9 years (51·7-54·0) to 75·6 years (75·3-75·9) for women. Despite this overall progress, there remains substantial variation in life expectancy at birth in 2017, which ranges from 49·1 years (46·5-51·7) for men in the Central African Republic to 87·6 years (86·9-88·1) among women in Singapore. The greatest progress across age groups was for children younger than 5 years; under-5 mortality dropped from 216·0 deaths (196·3-238·1) per 1000 livebirths in 1950 to 38·9 deaths (35·6-42·83) per 1000 livebirths in 2017, with huge reductions across countries. Nevertheless, there were still 5·4 million (5·2-5·6) deaths among children younger than 5 years in the world in 2017. Progress has been less pronounced and more variable for adults, especially for adult males, who had stagnant or increasing mortality rates in several countries. The gap between male and female life expectancy between 1950 and 2017, while relatively stable at the global level, shows distinctive patterns across super-regions and has consistently been the largest in central Europe, eastern Europe, and central Asia, and smallest in south Asia. Performance was also variable across countries and time in observed mortality rates compared with those expected on the basis of development. Interpretation: This analysis of age-sex-specifc mortality shows that there are remarkably complex patterns in population mortality across countries. The fndings of this study highlight global successes, such as the large decline in under-5 mortality, which refects signifcant local, national, and global commitment and investment over several decades. However, they also bring attention to mortality patterns that are a cause for concern, particularly among adult men and, to a lesser extent, women, whose mortality rates have stagnated in many countries over the time period of this study, and in some cases are increasing. © 2018 The Author(s)
Population and fertility by age and sex for 195 countries and territories, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017
No full textBackground: Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods. Methods: We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10–54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10–14 years and 50–54 years was estimated from data on fertility in women aged 15–19 years and 45–49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories. Findings: From 1950 to 2017, TFRs decreased by 49·4% (95% uncertainty interval [UI] 46·4–52·0). The TFR decreased from 4·7 livebirths (4·5–4·9) to 2·4 livebirths (2·2–2·5), and the ASFR of mothers aged 10–19 years decreased from 37 livebirths (34–40) to 22 livebirths (19–24) per 1000 women. Despite reductions in the TFR, the global population has been increasing by an average of 83·8 million people per year since 1985. The global population increased by 197·2% (193·3–200·8) since 1950, from 2·6 billion (2·5–2·6) to 7·6 billion (7·4–7·9) people in 2017; much of this increase was in the proportion of the global population in south Asia and sub-Saharan Africa. The global annual rate of population growth increased between 1950 and 1964, when it peaked at 2·0%; this rate then remained nearly constant until 1970 and then decreased to 1·1% in 2017. Population growth rates in the southeast Asia, east Asia, and Oceania GBD super-region decreased from 2·5% in 1963 to 0·7% in 2017, whereas in sub-Saharan Africa, population growth rates were almost at the highest reported levels ever in 2017, when they were at 2·7%. The global average age increased from 26·6 years in 1950 to 32·1 years in 2017, and the proportion of the population that is of working age (age 15–64 years) increased from 59·9% to 65·3%. At the national level, the TFR decreased in all countries and territories between 1950 and 2017; in 2017, TFRs ranged from a low of 1·0 livebirths (95% UI 0·9–1·2) in Cyprus to a high of 7·1 livebirths (6·8–7·4) in Niger. The TFR under age 25 years (TFU25; number of livebirths expected by age 25 years for a hypothetical woman who survived the age group and was exposed to current ASFRs) in 2017 ranged from 0·08 livebirths (0·07–0·09) in South Korea to 2·4 livebirths (2·2–2·6) in Niger, and the TFR over age 30 years (TFO30; number of livebirths expected for a hypothetical woman ageing from 30 to 54 years who survived the age group and was exposed to current ASFRs) ranged from a low of 0·3 livebirths (0·3–0·4) in Puerto Rico to a high of 3·1 livebirths (3·0–3·2) in Niger. TFO30 was higher than TFU25 in 145 countries and territories in 2017. 33 countries had a negative population growth rate from 2010 to 2017, most of which were located in central, eastern, and western Europe, whereas population growth rates of more than 2·0% were seen in 33 of 46 countries in sub-Saharan Africa. In 2017, less than 65% of the national population was of working age in 12 of 34 high-income countries, and less than 50% of the national population was of working age in Mali, Chad, and Niger. Interpretation: Population trends create demographic dividends and headwinds (ie, economic benefits and detriments) that affect national economies and determine national planning needs. Although TFRs are decreasing, the global population continues to grow as mortality declines, with diverse patterns at the national level and across age groups. To our knowledge, this is the first study to provide transparent and replicable estimates of population and fertility, which can be used to inform decision making and to monitor progress. Funding: Bill & Melinda Gates Foundation. © 2018 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens
