Albion College

About: Albion College is a education organization based out in Albion, Michigan, United States. It is known for research contribution in the topics: Population & Higher education. The organization has 485 authors who have published 754 publications receiving 20907 citations.

Cataclysm No More: New Views on the Timing and Delivery of Lunar Impactors

Abstract: If properly interpreted, the impact record of the Moon, Earth’s nearest neighbour, can be used to gain insights into how the Earth has been influenced by impacting events since its formation ~4.5 billion years (Ga) ago. However, the nature and timing of the lunar impactors – and indeed the lunar impact record itself – are not well understood. Of particular interest are the ages of lunar impact basins and what they tell us about the proposed “lunar cataclysm” and/or the late heavy bombardment (LHB), and how this impact episode may have affected early life on Earth or other planets. Investigations of the lunar impactor population over time have been undertaken and include analyses of orbital data and images; lunar, terrestrial, and other planetary sample data; and dynamical modelling. Here, the existing information regarding the nature of the lunar impact record is reviewed and new interpretations are presented. Importantly, it is demonstrated that most evidence supports a prolonged lunar (and thus, terrestrial) bombardment from ~4.2 to 3.4 Ga and not a cataclysmic spike at ~3.9 Ga. Implications for the conditions required for the origin of life are addressed.

Materialism and Money Spending Disposition as Predictors of Economic and Personality Variables

Abstract: This research explored the relationships between materialism and money spending attitudes on impulse buying tendencies, attitudes toward debt, sensation seeking, and openness to experience. Students and other adults (N = 266) completed a materialism scale, portions of two money conservation scales, an impulse buying scale, an attitudes toward debt scale, a sensation seeking scale, and an openness to experience scale. Simultaneous-entry multiple regression analyses revealed that materialism and money conservation were predictive of impulse buying, sensation seeking, and openness to experience. Two marginally significant interactions emerged. Individuals less materialistic and tight with money had particularly negative attitudes toward debt, and individuals less materialistic and loose with money were particularly open to experience. Results are discussed with respect to how materialism may be related to a variety of individual difference variables, both at the main effect level and in interaction with money spending attitudes. Tatzel (2002) proposed a taxonomy of "money worlds" in which she integrated the notions of materialism and money spending disposition. In her taxonomy, she cogently articulated how money spending penchants may combine with materialism to predict a number of other phenomena. The purpose of the current research is to empirically test some of the predictions she made. Materialism is "... a value representing the individual's orientation toward the role of possessions in life, serving to guide the types and quantities of goods purchased" (Mick, 1996, p. 108). To a great extent, research on materialism has tended to focus on materialism as a main effect. However, at least two studies have examined interactive effects of materialism. Burroughs and Rindfleisch (2002) examined how ownership of material objects and its negative relationship with well-being is a function of other important life values. Also, LaBarbera and Gurhan (1997) found that people high in materialism with lower incomes had lower levels of well-being than people high in materialism with higher incomes. Materialism at the main effect level has been a topic of a comprehensive study of how materialism is related to spending tendencies, saving, and debt. Watson (2003) found that materialistic people tended to be more likely to spend money, more likely to express positive attitudes toward borrowing money for luxury purchases, and less likely to own vehicles of savings (e.g., mutual funds) than were less materialistic people. The paucity of research on the interactions between materialism and other phenomena warrants further research. To better understand the different meanings that money holds for people, empirical research has focused primarily on the development of scales to assess such differences (e.g., Furnham, 1984; Tang, 1992; Yamauchi & Templer, 1982). These undertakings have each demonstrated that the meanings people ascribe to money are indeed diverse. For instance, in a factor analysis, Furnham (1984) found six distinct factors of money beliefs and behaviors, including obsession, power/spending, retention, security/conservatism, inadequacy, and effort/ability. In the current research, we were particularly interested in people's tendency to conserve (or not conserve) money, and how such a tendency may combine with materialistic values to predict economic attitudes (i.e., attitudes toward debt and impulse buying) and personality traits (i.e., sensation seeking and openness to experience). Money Attitudes, Materialism, and Tatzel's (2002) Taxonomy Tatzel (2002) proposed a litany of outcomes based on individuals' materialistic orientation and money spending penchants. She outlined the characteristics of four possible combinations of these variables as seen in Table 1. With respect to people who are loose with money, Tatzel distinguished between big spenders and experiencers. Big spenders are highly materialistic people who enjoy spending money, often view higher prices as a quality signifier, and who enjoy owning nice possessions. …

Late Quaternary volcanic activity in Marie Byrd Land: Potential 40Ar/39Ar-dated time horizons in West Antarctic ice and marine cores

Abstract: Late Quaternary volcanic activity at three major alkaline composite volcanoes in Marie Byrd Land, West Antarctica, is dominated by explosive eruptions, many capable of depositing ash layers as regional time-stratigraphic horizons in the West Antarctic Ice Sheet and in Southern Ocean marine sediments. A total of 20 eruptions at Mount Berlin, Mount Takahe, and Mount Siple are recorded in lava and welded and nonwelded pyroclastic fall deposits, mostly peralkaline trachyte in composition. The eruptions, dated by the 40Ar/39Ar laser-fusion and furnace step-heating methods, range in age from 571 to 8.2 ka. Tephra from these 40Ar/39Ar-dated Marie Byrd Land eruptions are identified by geochemical fingerprinting in the 1968 Byrd Station ice core. The 74 ka ice-core record contained abundant coarse ash layers, with model ice-flow ages ranging from 7.5 to 40 ka, all of which were previously geochemically correlated to the Mount Takahe volcano. We identify a one-to-one geochemical and age correlation of the youngest (ca. 7.5 ka) tephra layer in the Byrd ice core to an 8.2 ± 5.4 ka (2sigma uncertainty) pyroclastic deposit at Mount Takahe. We infer that the 20–30 ka tephra layers in the Byrd ice core actually were erupted from Mount Berlin, on the basis of age and geochemical similarities. If products of these youngest, as well as the older 40Ar/39Ar-dated eruptions are identified by geochemical fingerprinting in future ice and marine cores, they will provide the cores with independently dated time horizons. More than 12 40Ar/39Ar-dated tephra layers, exposed in bare ice on the summit ice cap of Mount Moulton, 30 km from their inferred source at Mount Berlin, range in age from 492 to 15 ka. These englacial tephra layers provide a minimum age of 492 ka for the oldest isotopically dated ice in West Antarctica. This well-dated section of locally derived glacial ice contains a potential “horizontal ice core” record of paleoclimate that extends back through several glacial-interglacial cycles. The coarse grain size and density of the englacial tephra (mean diameters 17–18 mm, densities 540–780 kg/m3), combined with their distance from source, indicate derivation from highly explosive Plinian eruptions of Mount Berlin.

The Impact of Host Diet on Wolbachia Titer in Drosophila

Abstract: While a number of studies have identified host factors that influence endosymbiont titer, little is known concerning environmental influences on titer. Here we examined nutrient impact on maternally transmitted Wolbachia endosymbionts in Drosophila. We demonstrate that Drosophila reared on sucrose- and yeast-enriched diets exhibit increased and reduced Wolbachia titers in oogenesis, respectively. The yeast-induced Wolbachia depletion is mediated in large part by the somatic TOR and insulin signaling pathways. Disrupting TORC1 with the small molecule rapamycin dramatically increases oocyte Wolbachia titer, whereas hyper-activating somatic TORC1 suppresses oocyte titer. Furthermore, genetic ablation of insulin-producing cells located in the Drosophila brain abolished the yeast impact on oocyte titer. Exposure to yeast-enriched diets altered Wolbachia nucleoid morphology in oogenesis. Furthermore, dietary yeast increased somatic Wolbachia titer overall, though not in the central nervous system. These findings highlight the interactions between Wolbachia and germline cells as strongly nutrient-sensitive, and implicate conserved host signaling pathways by which nutrients influence Wolbachia titer.

Botnet Economics: Uncertainty Matters

Abstract: Botnets have become an increasing security concern in today’s Internet. Thus far the mitigation to botnet attacks is a never ending arms race focusing on technical approaches. In this chapter, we model botnet-related cybercrimes as a result of profit-maximizing decision-making from the perspectives of both botnet masters and renters/attackers. From this economic model, we can understand the effective rental size and the optimal botnet size that can maximize the profits of botnet masters and attackers. We propose the idea of using virtual bots (honeypots running on virtual machines) to create uncertainty in the level of botnet attacks. The uncertainty introduced by virtual bots has a deep impact on the profit gains on the botnet market. With decreasing profitability, botnet-related attacks such as DDoS are reduced if not eliminated from the root cause, i.e. economic incentives.