New Scholarship from UNCW Faculty
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Publication date: Available online 29 August 2014
Author(s): Nick Galli , Trent Petrie , Christy Greenleaf , Justine Reel , Jennifer Carter
Despite a proliferation of research on disordered eating in female athletes, few studies have included male athletes. The purpose of this study was to determine which of five personality and psychological variables of interest (i.e., perfectionism, self-esteem, optimism, reasons for exercise, and appearance orientation) best predicted eating disorder status (i.e., symptomatic or asymptomatic) in male athletes. Two hundred three male athletes (M age =20.29, SD =1.64) from three National Collegiate Athletic Association (NCAA) Division I institutions participated. More athletes were asymptomatic (80.8%) than symptomatic (19.2%). None of the variables significantly predicted symptomatic status. These findings contrast the literature on predictors of disordered eating symptomatology among female athletes, and suggest the need for further research to identify other potential predictors of eating disturbance among male athletes.
Nile Delta exhibited a spatial reversal in the rates of shoreline retreat on the Rosetta Promontory comparing pre- and post-beach protection
Publication date: Available online 27 August 2014
Author(s): Eman Ghoneim , Jehan Mashaly , Douglas Gamble , Joanne Halls , Mostafa AbuBakr
The coastline of the Nile Delta experienced accelerated erosion since the construction of the Aswan High Dam in 1964 and, consequently, the entrapment of a large amount of river sediments behind it. The coastline of the Rosetta promontory showed the highest erosion in the Delta with an average retreat rate of 137.4m y−1. In 1991, in an effort to mitigate sediment loss, a 4.85km long seawall was built on the outer margin of the promontory. For additional beach protection, 15 groins were constructed along the eastern and western sides of the seawall in 2003 and 2005. To quantify erosion and accretion patterns along the Rosetta promontory, eleven Landsat images acquired at unequal intervals during a 40year time span (1972 and 2012) were analyzed. The positions of shorelines were automatically extracted from satellite imagery and compared with three very high resolution QuickBird and WorldView2 images for data validation. Analysis of the rates of shoreline change revealed that the construction of the seawall was largely successful in halting the recession along the tip of the promontory, which lost 10.8km2 prior to coastal protection. Conversely, the construction of the 15 groins has negatively affected the coastal morphology of the promontory and caused a reversal from accretion to fast erosion along the promontory leeside, where some segments of the shoreline have undergone as much as 30.8m y−1 of erosion. Without hard structures, the tip of the Rosetta promontory would have retreated 2.3km by 2013 and lost 7.2km2 of land. About 10% of this land is deltaic fertile cultivated farms. Moreover, without additional protection the sides of the promontory will lose about 1.3km2 of land and the coastline would recede at an average rate of 200m by 2020. Unless action is taken, coastal erosion, enhanced by rising sea level, will steadily eat away the Nile Delta at an alarming rate. The successful demonstration of the advocated procedures in this study could be adopted, with appropriate modifications, for other deltas worldwide.
Recurrent vernal presence of the toxic Alexandrium tamarense/Alexandrium fundyense (Dinoflagellata) species complex in Narragansett Bay, USA
Publication date: February 2014
Source:Harmful Algae, Volume 32
Author(s): David G. Borkman , Theodore J. Smayda , Erika N. Schwarz , Leanne J. Flewelling , Carmelo R. Tomas
The vernal occurrence of toxic dinoflagellates in the Alexandrium tamarense/Alexandrium fundyense species complex in an enclosed embayment of Narragansett Bay (Wickford Cove, Rhode Island) was documented during 2005 and 2009–2012. This is the first report of regular appearance of the Alexandrium fundyense/Alexandrium tamarense species complex in Narragansett Bay. Thecal plate analysis of clonal isolates using SEM revealed cells morphologically consistent with both Alexandrium tamarense Lebour (Balech) and Alexandrium fundyense Balech. Additionally, molecular analyses confirmed that the partial sequences for 18S through the D1–D2 region of 28S were consistent with the identity of the two Alexandrium species. Toxin analyses revealed the presence of a suite of toxins (C1/2, B1 (GTX-5), STX, GTX-2/3. Neo, and GTX-1/4) in both Alexandrium tamarense (6.31fmolcell−1 STXequiv.) and Alexandrium fundyense (9.56fmolcell−1 STXequiv.) isolated from Wickford Cove; the toxicity of a Narragansett Bay Alexandrium peruvianum isolate (1.79fmolcell−1 STXequiv.) was also determined. Combined Alexandrium tamarense/Alexandrium fundyense abundance in Wickford Cove reached a peak abundance of 1280cellsL−1 (May of 2010), with the combined abundance routinely exceeding levels leading to shellfishing closures in other systems. The toxic Alexandrium tamarense/Alexandrium fundyense species complex appears to be a regular component of the lower Narragansett Bay phytoplankton community, either newly emergent or previously overlooked by extant monitoring programs.
Publication date: Available online 27 August 2014
Author(s): Nicholas S. Thaler , Griffin P. Sutton , Daniel N. Allen
Social cognition is a functionally relevant predictor of capacity in schizophrenia, though research concerning its value for bipolar disorder is limited. The current investigation examined the relationship between two social cognitive factors and functional capacity in bipolar disorder. This study included 48 individuals with bipolar disorder (24 with psychotic features) and 30 patients with schizophrenia. Multiple regression controlling for estimated IQ scores was used to assess the predictive value of social cognitive factors on the UCSD Performance-Based Functional Skills Assessment (UPSA). Results found that for the bipolar with psychosis and schizophrenia groups, the social/emotion processing factor predicted the UPSA while the theory of mind factor did not predict this measure. This supports the clinical utility of evaluating emotion processing in individuals with a history of psychosis. As theory of mind did not contribute to model, impairments in this construct may be due to a generalized cognitive deficit. In contrast, social/emotion processing may be linked to distinct neurobiological processes associated with psychosis.
Publication date: Available online 26 August 2014
Author(s): S.D. Emslie , M.J. Polito , R. Brasso , W.P. Patterson , L. Sun
Ornithogenic or bird-formed soils have accumulated in many coastal regions around Antarctica as a result of breeding activities by pygoscelid penguins, especially the Adélie penguin (Pygoscelis adeliae). These soils are often deep, range from hundreds to thousands of years old, and contain a natural archive of penguin tissues and those of their prey. In some regions, these tissues are extremely well preserved by the dry, cold environment and include complete and partial penguin mummies, feathers, bone, and eggshell. Hard parts of prey (fish bones, otoliths, and squid beaks) also commonly occur in these deposits from the penguin guano as it accumulates during soil development. Here, we review how research on these soils and the tissues they contain has progressed since they were first identified and described. These studies have provided not only valuable information on penguin occupation history with climate change since the Pleistocene, but also whole ecosystem responses to perturbations such as the ‘krill surplus’ that is hypothesized to have occurred following historic depletion of seals and whales in the 18th–20th centuries. New findings in the Ross Sea indicate how penguin occupation and abandonment cycles have progressed over millennia in relation to climate change. In addition, stable isotope analysis of δ15N and δ13C in ancient and modern Adélie penguin tissues (feathers, bone, eggshell and membrane) and guano support the ‘krill surplus’ hypothesis in showing a dietary shift from fish to krill over the past ∼200 years. Other recent studies have focused on stable isotope analyses of penguin prey remains, as well as ancient DNA and mercury analyses of penguin tissues recovered from ornithogenic soils. An analysis of fish otoliths recovered from ancient guano provide a means to investigate values of otolith carbonate δ18O, which correlates with other paleoclimatic records, and can be used as a proxy for changing ocean temperatures through time. In addition, measurements of total mercury (Hg) in penguin egg membrane from abandoned colonies up to 800 years old indicate significantly higher mercury levels in the past compared to modern penguins, likely due to a greater reliance on higher trophic prey prior to the proposed ‘krill surplus’. All of these studies indicate that ornithogenic soils and the natural archive of tissues they contain provide a unique means to integrate both terrestrial and marine records with ecosystem studies and climate change, past and present, in Antarctica.
Publication date: Available online 21 August 2014
Source:The Journal of Social Studies Research
Author(s): Jeremy Hilburn , Brad M. Maguth
This qualitative case study draws on interview and focus group data from six Civics teachers. As global education scholars assert, local, national, and global “levels of citizenship” do not occur in a vacuum, instead, each level is invariably connected to one another. Teachers in this study, however, placed different priorities on the levels – prioritizing the national, minimizing the local, and marginalizing the global. Participants also used different teaching strategies in order to teach the different levels: emphasizing knowledge acquisition and values transmission at the national level and more active civic behaviors at the local level.
Evidence-Based Knowledge, Skills, and Attitudes for Scholarly Writing Development Across all Levels of Nursing Education
Publication date: July–August 2014
Source:Journal of Professional Nursing, Volume 30, Issue 4
Author(s): Diane F. Hunker , Elizabeth A. Gazza , Teresa Shellenbarger
Because nursing care in health care settings becomes more complex, nurses are called upon to work effectively with other health care providers to deliver high-quality evidence-based care. To do so in a cost effective and efficient manner requires the development of effective oral and written communication skills in nurses. One form of written communication is scholarly writing. Scholarly writing is defined by the authors as writing that is specialized in nursing, communicates original thought, includes support from a body of literature, contains formal language consistent with the discipline of nursing, and is formatted in a manner consistent with peer-review publications. Faculty who facilitate the development of these skills face inconsistencies in students' writing ability and development across programs and levels of education. Nurse educators need to understand how to develop these communication skills for students enrolled at various educational levels and to teach students how to share information in a scholarly way.
Validation of taxon-specific sampling by novice collectors for studying drilling predation in fossil bivalves
Publication date: 15 October 2014
Source:Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 412
Author(s): Kelly E. Hattori , Patricia H. Kelley , Gregory P. Dietl , Nicholas O. Moore , Sarah L. Simpson , Anna M. Zappulla , Kristina J. Ottens , Christy C. Visaggi
Although bulk sampling has been considered to provide more robust information on predation in the fossil record than taxon-specific (targeted) sampling, previous work suggested that targeted sampling, even by a trained novice, can yield results comparable to bulk sampling. The present study further investigates potential bias introduced by collectors with different experience levels by comparing drilling predation metrics for samples made by five novice and three veteran collectors. We demonstrate that trained novices produce results comparable to those of experienced collectors, and that results of targeted sampling are comparable to bulk sampling. Targeted sampling was performed in the lower Waccamaw Formation (lower Pleistocene) at Register Quarry near Old Dock, NC. Five replicate taxon-specific samples were obtained by each collector for the bivalves Astarte concentrica, Cyclocardia granulata, and Lirophora latilirata. Shell length and thickness were measured and position and size of drillholes were determined. Frequency of left valves, drilling frequency, prey effectiveness, and size selectivity were determined for each taxon replicate. For each variable, the results for the novice collectors were compared to those from bulk samples and all veteran collectors. Nearly all significant differences in the unstandardized data occurred in the size-related variables length and thickness. When data were size standardized, as in many other drilling predation studies, only 3.3% of 174 tests for statistical differences in collection methods were significant, and none of the 157 tests for differences in novice and veteran sampling was significant. Previous results were not anomalous; use of targeted sampling in studying drilling predation is again validated and collector expertise is shown to have minimal impact.
Implicit alcohol cognitions in risky drinking nicotine users with and without co-morbid major depressive disorder
Publication date: April 2014
Source:Addictive Behaviors, Volume 39, Issue 4
Author(s): Amy M. Cohn , Caroline Cobb , Brett T. Hagman , Amy Cameron , Sarah Ehlke , Jessica N. Mitchell
Objective Alcohol consumption, nicotine use, and major depressive disorder (MDD) are highly co-morbid. The negative reinforcement model of addiction would suggest that smokers may consume alcohol to relieve negative affective symptoms, such as those associated with MDD and withdrawal from nicotine. Over time, these behaviors may become so strongly paired together that they automatically activate a desire to use alcohol, even in the absence of conscious or deliberate intention. This study examined implicit alcohol cognitions in 146 risky drinking nicotine users (n=83) and non-users (n=63), to help uncover cognitive mechanisms that link drinking, nicotine use, and depression together. We proposed that nicotine users with a history of MDD would have stronger implicit motivations to drink than non-nicotine users without MDD. Method Participants were assessed on lifetime MDD (n=84) or no MDD (n=62), and then completed an Implicit Association Task designed to test the strength of associations between alcohol pictures and “approach” words. Results Regression analyses showed that implicit alcohol–approach attitudes were stronger among risky drinking nicotine users than non-users. Alcohol–approach motivations were also stronger among risky drinking nicotine users compared to non-users with a history of MDD; nicotine use was unrelated to implicit alcohol cognitions for risky drinkers without MDD. Conclusions Implicit cognitive processes may be targeted in behavioral and pharmacological treatments in risky drinking nicotine users, particularly those with depression comorbidity.
Goal specificity: A proxy measure for improvements in environmental outcomes in collaborative governance
Publication date: 1 December 2014
Source:Journal of Environmental Management, Volume 145
Author(s): Jennifer C. Biddle , Tomas M. Koontz
Collaborative governance critics continually call for evidence to support its prevalent use. As is often the case in environmental policy, environmental outcomes occur at a rate incompatible with political agendas. In addition, a multitude of possibly confounding variables makes it difficult to correlate collaborative governance processes with environmental outcomes. The findings of this study offer empirical evidence that collaborative processes have a measurable, beneficial effect on environmental outcomes. Through the use of a unique paired-waterbody design, our dataset reduced the potential for confounding variables to impact our environmental outcome measurements. The results of a path analysis indicate that the output of setting specific pollutant reduction goals is significantly related to watershed partnerships' level of attainment of their environmental improvement goals. The action of setting specific goals (e.g. percentage of load reductions in pollutant levels) is fostered by sustained participation from partnership members throughout the lifecycle of the collaborative. In addition, this study demonstrates the utility of logic modeling for environmental planning and management, and suggests that the process of setting specific pollutant reduction goals is a useful proxy measure for reporting progress towards improvements in environmental outcomes when long-term environmental data are not available.
Isolated salt marsh colonization by a resident species, mummichog (Fundulus heteroclitus), and a transient species, pinfish (Lagodon rhomboides)
Publication date: November 2014
Source:Journal of Experimental Marine Biology and Ecology, Volume 460
Author(s): David L. Meyer , Martin H. Posey
The potential for species to populate habitat patches is directly influenced by dispersal and colonization abilities. To test the dispersal and colonization capabilities of a resident, mummichog (Fundulus heteroclitus), and a transient, pinfish (Lagodon rhomboides), marsh species, isolated-island marsh sites were used for removal and colonization assessments, while a nearby non-removal site was used to concurrently monitor temporal catch variability. F. heteroclitus and L. rhomboides were removed from island marshes using baited minnow traps during mid-fall 2004 (after F. heteroclitus spring/summer spawn, and prior to L. rhomboides winter recruitment), then monitored for colonization through the peak F. heteroclitus spawning season the following year (July 2005). Significant abundance reductions occurred for F. heteroclitus and L. rhomboides due to removal efforts, and for L. rhomboides due to temperature-dependent offshore migration. F. heteroclitus and L. rhomboides were capable of seasonally colonizing marsh sites separated by >800m of open water, which was twice the previously documented distance for F. heteroclitus movement within marsh habitats. Results from size-class analysis indicated that F. heteroclitus populated sites via adult colonization from nearby marshes within weeks to months of removal. L. rhomboides site colonization occurred by young-of-year (YOY) recruitment and was documented within months of removal efforts, when YOY attained sufficient size for gear collection. Low population contribution by F. heteroclitus YOY to island compared to mainland type marsh indicated that island marshes were primarily sustained by immigrants, which colonized during late fall and winter, while YOY production sustained the population at the mainland marsh. Island marshes acted as sinks for estuarine F. heteroclitus populations. F. heteroclitus population characteristics were determined during: (1) the spring/summer spawn and recruitment, and (2) the late fall/winter dispersal–colonization by adult F. heteroclitus. Further, the F. heteroclitus dispersal–colonization phase maintains the species' large-scale (geographic) distribution, while the spawn–recruitment phase maintains the small-scale (local) populations. L. rhomboides recruitment and dispersal–colonization occur simultaneously during late fall/winter when pulsed dispersal–colonization by recruits maintains geographic and local populations.
Publication date: October 2014
Source:Neurobiology of Learning and Memory, Volume 114
Author(s): Andrew Hawkey , L. Brooke April , Mark Galizio
The effects of acute and sub-chronic MDMA were assessed using a procedure designed to test rodent working memory capacity: the odor span task (OST). Rats were trained to select an odor that they had not previously encountered within the current session, and the number of odors to remember was incremented up to 24 during the course of each session. In order to separate drug effects on the OST from more general performance impairment, a simple olfactory discrimination was also assessed in each session. In Experiment 1, acute doses of MDMA were administered prior to select sessions. MDMA impaired memory span in a dose-dependent fashion, but impairment was seen only at doses (1.8 and 3.0mg/kg) that also increased response omissions on both the simple discrimination and the OST. In Experiment 2, a sub-chronic regimen of MDMA (10.0mg/kg, twice daily over four days) was administered after OST training. There was no evidence of reduced memory span following sub-chronic MDMA, but a temporary increase in omission errors on the OST was observed. In addition, rats exposed to sub-chronic MDMA showed delayed learning when the simple discrimination was reversed. Overall, the disruptive effects of both acute and sub-chronic MDMA appeared to be due to non-mnemonic processes, rather than effects on specific memory functions.
Assessing source contributions to particulate organic matter in a subtropical estuary: A biomarker approach
Publication date: October 2014
Source:Organic Geochemistry, Volume 75
Author(s): Ding He , Ralph N. Mead , Laura Belicka , Oliva Pisani , Rudolf Jaffé
Assessing the sources and quantifying the contributions of particulate organic matter (POM) in estuaries is a challenge. Here we apply source-specific biomarkers to assess POM sources in an estuary receiving suspended material from freshwater wetlands, fringe mangroves and coastal environments. A three end-member mixing model, including terrestrial, estuarine and marine end-member contributions was developed and successfully validated to assess general OM dynamics and hydrologic processes that control POM distributions within the Shark River estuary in South Florida. Low tide and wet season conditions coincided with an enhanced signal of the freshwater end-member biomarker abundance, while high tide and dry season conditions resulted in enhanced POM input of marine origin. Incoming tide was observed to be an important factor in the re-suspension and tidal pumping of mangrove-derived POM, which seems to be the dominant source of particulate organic carbon (POC) in the estuary. The three end-member conceptual model was tested to obtain a rough estimate of POC source strength, with the ultimate goal of constraining carbon budgets in this sub-tropical estuary. Mangrove-derived POC flux of ca. 5.3×105 to 1.0×106 kg/yr POC from the Shark River to the Gulf of Mexico were estimated, but end-member values used in the assessment need to be better constrained to reduce the degree of variability.
Molluscan live–dead agreement in anthropogenically stressed seagrass habitats: Siliciclastic versus carbonate environments
Publication date: 15 September 2014
Source:Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 410
Author(s): Chelsea A. Korpanty , Patricia H. Kelley
Molluscan live–dead fidelity studies investigate the influences of anthropogenic activities on marine ecosystems by comparing the taxonomic composition of a living community to its corresponding death assemblage. Environments subjected to intense anthropogenic stresses tend to yield low fidelity (high discordance) in rank-order abundance and taxonomic similarity between living and dead assemblages. This project assesses the sensitivity of the live–dead approach by applying various fidelity metrics – community richness (Delta-S), evenness (Delta-PIE), rank-order correlation (Spearman rho), and taxonomic similarity (Jaccard–Chao) – to molluscan assemblages in seagrass habitats exposed to anthropogenic stresses in different sedimentary environments. Our study sites include siliciclastic sites in North Carolina, carbonate sites in Florida Bay, and a siliciclastic–carbonate transition locality along the coast of southern Florida. The dominant forms of human stresses at these seagrass sites consist of increased freshwater runoff, increased nutrient runoff, and physical substrate disturbance by dredging (North Carolina) and propeller scarring (Florida Bay). As a result of such anthropogenic stresses, we expected to find low live–dead fidelity results at all of our study sites. We also anticipated variations in the results between sedimentary environments, reflecting intrinsic differences in how molluscan material accumulates and is preserved in siliciclastic versus carbonate settings. Using bulk sediment samples, fidelity analyses consistently yield greater live–dead disagreement at the siliciclastic sites. Despite well-documented historical human stresses to Florida Bay and sediment cores indicating multiple ecological shifts in response to human impacts over time, results from carbonate localities yield higher fidelity and provide little evidence for ecological change. We argue that greater time averaging allows for the death assemblages at the siliciclastic sites to retain a longer memory of the local communities, thus preserving evidence of local ecological changes. In contrast, less time averaging and more rapid live–dead equilibration in carbonate sediments reduces the signal of community changes. Thus we propose that the live–dead fidelity approach is more sensitive at detecting recent ecological changes in siliciclastic versus carbonate environments, confirming the conservative nature of the approach and demonstrating the role of taphonomic bias in live–dead methodology.
Lysylated phospholipids stabilize models of bacterial lipid bilayers and protect against antimicrobial peptides
Publication date: September 2014
Source:Biochimica et Biophysica Acta (BBA) - Biomembranes, Volume 1838, Issue 9
Author(s): Elizabeth Cox , Austen Michalak , Sarah Pagentine , Pamela Seaton , Antje Pokorny
Aminoacylated phosphatidylglycerols are common lipids in bacterial cytoplasmic membranes. Their presence in Staphylococcus aureus has been linked to increased resistance to a number of antibacterial agents, including antimicrobial peptides. Most commonly, the phosphatidylglycerol headgroup is esterified to lysine, which converts anionic phosphatidylglycerol into a cationic lipid with a considerably increased headgroup size. In the present work, we investigated the interactions of two well-studied antimicrobial peptides, cecropin A and mastoparan X, with lipid vesicles composed of 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) and 1-palmitoyl-2-oleoyl-phosphatidylglycerol (POPG), containing varying fractions of an aminoacylated phosphatidylethanolamine, a stable analog of the corresponding phosphatidylglycerol-derivative. To differentiate between the effects of headgroup size and charge on peptide–lipid interactions, we synthesized two different derivatives. In one, the headgroup was modified by the addition of lysine, and in the other, by glutamine. The modification by glutamine results in a phospholipid with a headgroup size comparable to that of the lysylated version. However, whereas lysyl-phosphatidylethanolamine (Lys-PE) is cationic, glutaminyl-phosphatidylethanolamine (Gln-PE) is zwitterionic. We found that binding of mastoparan X and cecropin A was not significantly altered if the content of aminoacylated phosphatidylethanolamines did not exceed 20mol.%, which is the concentration found in bacterial membranes. However, a lysyl-phosphatidylethanolamine content of 20mol% significantly inhibits dye release from lipid vesicles, to a degree that depends on the peptide. In the case of mastoparan X, dye release is essentially abolished at 20mol.% lysyl-phosphatidylethanolamine, whereas cecropin A is less sensitive to the presence of lysyl-phosphatidylethanolamine. These observations are understood through the complex interplay between peptide binding and membrane stabilization as a function of the aminoacylated lipid content. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova.
Publication date: September 2014
Source:Biochimica et Biophysica Acta (BBA) - Biomembranes, Volume 1838, Issue 9
Author(s): Paulo F. Almeida
Recently, new and improved methods have been developed to measure translocation of membrane-active peptides (antimicrobial, cytolytic, and amphipathic cell-penetrating peptides) across lipid bilayer membranes. The hypothesis that translocation of membrane-active peptides across a lipid bilayer is determined by the Gibbs energy of insertion of the peptide into the bilayer is re-examined in the light of new experimental tests. The original hypothesis and its motivation are first revisited, examining some of the specific predictions that it generated, followed by the results of the initial tests. Translocation is understood as requiring two previous steps: binding and insertion in the membrane. The problem of peptide binding to membranes, its prediction, measurement, and calculation are addressed. Particular attention is given to understanding the reason for the need for amphipathic structures in the function of membrane-active peptides. Insertion into the membrane is then examined. Hydrophobicity scales are compared, and their influence on calculations is discussed. The relation between translocation and graded or all-or-none peptide-induced flux from or into lipid vesicles is also considered. Finally, the most recent work on translocation is examined, both experimental and from molecular dynamics simulations. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova.
Publication date: September 2014
Source:Resources Policy, Volume 41
Author(s): Jonathan A. Batten , Cetin Ciner , Brian M Lucey
We examine the long term dynamic relation between inflation and the price of gold. We begin by showing that there is no cointegration between gold and inflation if the volatile period of the early 1980s is excluded from the data. However, we are also able to demonstrate that there is significant time variation in the relation, such that comovement between the variables has indeed increased in the last decade. Examination of the underlying macroeconomic factors that could generate time variation in the gold–inflation linkage suggests gold׳s sensitivity to inflation is related to interest rate changes, a finding that highlights the monetary nature of gold as a commodity.
Publication date: 1 November 2014
Source:Marine Geology, Volume 357
Author(s): Andrew C. Kemp , Christopher E. Bernhardt , Benjamin P. Horton , Robert E. Kopp , Christopher H. Vane , W. Richard Peltier , Andrea D. Hawkes , Jeffrey P. Donnelly , Andrew C. Parnell , Niamh Cahill
Late Holocene relative sea-level (RSL) reconstructions can be used to estimate rates of land-level (subsidence or uplift) change and therefore to modify global sea-level projections for regional conditions. These reconstructions also provide the long-term benchmark against which modern trends are compared and an opportunity to understand the response of sea level to past climate variability. To address a spatial absence of late Holocene data in Florida and Georgia, we reconstructed ~1.3m of RSL rise in northeastern Florida (USA) during the past ~2600years using plant remains and foraminifera in a dated core of high salt-marsh sediment. The reconstruction was fused with tide-gauge data from nearby Fernandina Beach, which measured 1.91±0.26mm/year of RSL rise since 1900 CE. The average rate of RSL rise prior to 1800 CE was 0.41±0.08mm/year. Assuming negligible change in global mean sea level from meltwater input/removal and thermal expansion/contraction, this sea-level history approximates net land-level (subsidence and geoid) change, principally from glacio-isostatic adjustment. Historic rates of rise commenced at 1850–1890 CE and it is virtually certain (P =0.99) that the average rate of 20th century RSL rise in northeastern Florida was faster than during any of the preceding 26 centuries. The linearity of RSL rise in Florida is in contrast to the variability reconstructed at sites further north on the U.S. Atlantic coast and may suggest a role for ocean dynamic effects in explaining these more variable RSL reconstructions. Comparison of the difference between reconstructed rates of late Holocene RSL rise and historic trends measured by tide gauges indicates that 20th century sea-level trends along the U.S. Atlantic coast were not dominated by the characteristic spatial fingerprint of melting of the Greenland Ice Sheet.