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Huntingdon, PA, United States

Juniata College is a private American liberal arts college in Huntingdon, Pennsylvania, United States. Founded in 1876 as a co-educational school, it was the first college started by the Church of the Brethren. Today, Juniata has about 1,600 students, who hail from 28 states and territories and 26 foreign countries. Its current president is Dr. James A. Troha. Wikipedia.

Mathur R.,Juniata College | Fantle M.S.,Pennsylvania State University
Elements | Year: 2015

Acompilation of copper isotopic compositions (δ65Cu) from supergene systems suggests distinct differences in the mean δ65Cu of Cu in leach cap (δ65Cu = -1.2 ± 3.5‰), enrichment zone (mean δ65Cu = +1.2 ± 4.2‰), and fluids (mean δ65Cu = +0.9 ± 1.3‰) relative to the high-temperature sulfides that comprise the primary ore (δ65Cu = +0.1 ± 0.6‰). These isotopic differences can be explained by the oxidative dissolution of primary ore minerals, such as chalcopyrite, and the subsequent precipitation of oxides in the near-surface system and of sulfides at depth. A dynamic mass balance model predicts the observed Cu isotopic compositions of the Cu reservoirs in nature and constrains the temporal isotopic evolution of supergene systems. From the model, these systems isotopically evolve to substantial extents over 500 ka to 5 Ma time scales. In relatively closed systems, percent-level loss of Cu from the solid (with δ65Cu values >>0‰) is possible, suggesting that supergene systems are important components of the global Cu cycle. Source

Killen S.S.,Montpellier University | Atkinson D.,University of Liverpool | Atkinson D.,National Center for Ecological Analysis And Synthesis | Glazier D.S.,Juniata College
Ecology Letters | Year: 2010

Metabolic energy fuels all biological processes, and therefore theories that explain the scaling of metabolic rate with body mass potentially have great predictive power in ecology. A new model, that could improve this predictive power, postulates that the metabolic scaling exponent (b) varies between 2/3 and 1, and is inversely related to the elevation of the intraspecific scaling relationship (metabolic level, L), which in turn varies systematically among species in response to various ecological factors. We test these predictions by examining the effects of lifestyle, swimming mode and temperature on intraspecific scaling of resting metabolic rate among 89 species of teleost fish. As predicted, b decreased as L increased with temperature, and with shifts in lifestyle from bathyal and benthic to benthopelagic to pelagic. This effect of lifestyle on b may be related to varying amounts of energetically expensive tissues associated with different capacities for swimming during predator-prey interactions. © 2009 Blackwell Publishing Ltd/CNRS. Source

Glazier D.S.,Juniata College
Biological Reviews | Year: 2015

A common, long-held belief is that metabolic rate drives the rates of various biological, ecological and evolutionary processes. Although this metabolic pacemaker view (as assumed by the recent, influential 'metabolic theory of ecology') may be true in at least some situations (e.g. those involving moderate temperature effects or physiological processes closely linked to metabolism, such as heartbeat and breathing rate), it suffers from several major limitations, including: (i) it is supported chiefly by indirect, correlational evidence (e.g. similarities between the body-size and temperature scaling of metabolic rate and that of other biological processes, which are not always observed) - direct, mechanistic or experimental support is scarce and much needed; (ii) it is contradicted by abundant evidence showing that various intrinsic and extrinsic factors (e.g. hormonal action and temperature changes) can dissociate the rates of metabolism, growth, development and other biological processes; (iii) there are many examples where metabolic rate appears to respond to, rather than drive the rates of various other biological processes (e.g. ontogenetic growth, food intake and locomotor activity); (iv) there are additional examples where metabolic rate appears to be unrelated to the rate of a biological process (e.g. ageing, circadian rhythms, and molecular evolution); and (v) the theoretical foundation for the metabolic pacemaker view focuses only on the energetic control of biological processes, while ignoring the importance of informational control, as mediated by various genetic, cellular, and neuroendocrine regulatory systems. I argue that a comprehensive understanding of the pace of life must include how biological activities depend on both energy and information and their environmentally sensitive interaction. This conclusion is supported by extensive evidence showing that hormones and other regulatory factors and signalling systems coordinate the processes of growth, metabolism and food intake in adaptive ways that are responsive to an organism's internal and external conditions. Metabolic rate does not merely dictate growth rate, but is coadjusted with it. Energy and information use are intimately intertwined in living systems: biological signalling pathways both control and respond to the energetic state of an organism. This review also reveals that we have much to learn about the temporal structure of the pace of life. Are its component processes highly integrated and synchronized, or are they loosely connected and often discordant? And what causes the level of coordination that we see? These questions are of great theoretical and practical importance. © 2014 Cambridge Philosophical Society. Source

Duina A.A.,Hendrix College | Miller M.E.,Rhodes College | Keeney J.B.,Juniata College
Genetics | Year: 2014

The budding yeast Saccharomyces cerevisiae is a powerful model organism for studying fundamental aspects of eukaryotic cell biology. This Primer article presents a brief historical perspective on the emergence of this organism as a premier experimental system over the course of the past century. An overview of the central features of the S. cerevisiae genome, including the nature of its genetic elements and general organization, is also provided. Some of the most common experimental tools and resources available to yeast geneticists are presented in a way designed to engage and challenge undergraduate and graduate students eager to learn more about the experimental amenability of budding yeast. Finally, a discussion of several major discoveries derived from yeast studies highlights the far-reaching impact that the yeast system has had and will continue to have on our understanding of a variety of cellular processes relevant to all eukaryotes, including humans. © 2014 by the Genetics Society of America. Source

Harmon R.S.,USACE ERDC International Research Office | Russo R.E.,Lawrence Berkeley National Laboratory | Hark R.R.,Juniata College
Spectrochimica Acta - Part B Atomic Spectroscopy | Year: 2013

Applications of laser-induced breakdown spectroscopy (LIBS) have been growing rapidly and continue to be extended to a broad range of materials. This paper reviews recent application of LIBS for the analysis of geological and environmental materials, here termed "GEOLIBS". Following a summary of fundamentals of the LIBS analytical technique and its potential for chemical analysis in real time, the history of the application of LIBS to the analysis of natural fluids, minerals, rocks, soils, sediments, and other natural materials is described. © 2013 Elsevier B.V. All rights reserved. Source

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