Late Quaternary glacial and periglacial environments, Snake Range, Nevada

Limited research has been conducted on the paleoclimatic significance of glacial and periglacial features in the Great Basin. Glacial features in the range were first recognized and described by early explorers (Gilbert, 1875; Simpson; 1876 and Russell, 1884) and subsequent authors have continued to substantiate and elaborate on earlier reports (Heald, 1956; Kramer, 1962; Currey, 1969; Peigat, 1980; Osborn and Bevis, 2001). Since this early reconnaissance work, few studies have focused on the Late Quaternary evolution and paleoclimatic implications of glacial and periglacial landforms in the Great Basin (Wayne, 1983; Osborn, 1989; Bevis, 1995; and Osborn and Bevis, 2001). Wayne (1984) describes relict rock glaciers, sorted circles, debris islands, solifluction lobes and sorted stripes in the Ruby, Schell Creek, and Snake ranges. While Currey (1969) and Osborn and Bevis, (2001) discuss the distribution of rock glaciers in numerous ranges throughout the Great Basin, including the Snake Range, and the surrounding regions; This study presents new data on the glacial and periglacial Late Quaternary conditions in the interior Great Basin based on studies carried out in the Snake Range, located in east-central Nevada. I propose the Lehman rock glacier is an ice-cemented landform that evolved via a recessional genesis, contrary to present glacial or periglacial models that primarily propose constructional geneses for rock glaciers. Preliminary GPR evidence suggests the Lehman rock glacier may retain interstitial lenses of ice; remnant ice that has stagnated under modern climate conditions; The spatial distribution of both glacial and periglacial landforms provides paleoclimatic information derived using field evidence and computer modeling. Neoglacial temperature depression estimates calculated using modern freezing and thawing indices for relict rock glaciers, range from -0.25°C to -1.00°C while temperature estimates calculated using the methodology described by Frauenfelder and Kaab, (2000) and Frauenfelder et al., (2001) are 0.35 to 0.97 degrees lower than those calculated using freezing and thawing indices. Full Glacial MAAT depression estimates range from approximately -5.16°C to -6.61°C calculated using periglacial landforms, to approximately -4.55°C to -5.77°C, calculated from reconstructed Angel Lake equilibrium line altitudes (ELAs); Finally, using scanning electron microscopy, it is possible to differentiate between a glacial and non-glacial origin for pebbles and cobbles entrained in enigmatic sedimentary deposits is a useful tool. Each depositional environment creates distinct micro-features that can be identified and used to establish a glacial or non-glacial history

Pedogenic gypsum of southern New Mexico: Genesis, morphology, and stable isotopic signature

Recent work in Canada and Iran (Dowuona et al., 1992 and Khademi et al., 1997a; 1997b) suggested a correlation exists between the delta18 O and deltaD ratios of the hydration water of pedogenic gypsum and the delta18O/deltaD ratios of meteoric water. However, a pedogenic origin for the sampled gypsum was not clearly supported and the results from this procedure were not compared to other paleoclimatic indicators. Therefore, the goals of this study were, (1) evaluate the genesis and soil morphology of pedogenic gypsum in and to semi-arid regions and (2) determine the applicability of pedogenic gypsum as a paleoclimatic indicator; Six profiles containing soils of late Pleistocene through Holocene age in the Tularosa and Jornada basins of Southern New Mexico were described and sampled for isotopic analysis. Gypsum soil morphology was expanded to include a new snowball morphology, as well as Stage I filaments and Stage II nodules, a classification scheme formerly only applied to carbonate morphology. A pedogenic origin for gypsum crystals found throughout the six profiles was determined using a scanning electron microscope. (Abstract shortened by UMI.)

Causal hierarchy within the thalamo-cortical network in spike and wave discharges

Background: Generalised spike wave (GSW) discharges are the electroencephalographic (EEG) hallmark of absence seizures, clinically characterised by a transitory interruption of ongoing activities and impaired consciousness, occurring during states of reduced awareness. Several theories have been proposed to explain the pathophysiology of GSW discharges and the role of thalamus and cortex as generators. In this work we extend the existing theories by hypothesizing a role for the precuneus, a brain region neglected in previous works on GSW generation but already known to be linked to consciousness and awareness. We analysed fMRI data using dynamic causal modelling (DCM) to investigate the effective connectivity between precuneus, thalamus and prefrontal cortex in patients with GSW discharges. Methodology and Principal Findings: We analysed fMRI data from seven patients affected by Idiopathic Generalized Epilepsy (IGE) with frequent GSW discharges and significant GSW-correlated haemodynamic signal changes in the thalamus, the prefrontal cortex and the precuneus. Using DCM we assessed their effective connectivity, i.e. which region drives another region. Three dynamic causal models were constructed: GSW was modelled as autonomous input to the thalamus (model A), ventromedial prefrontal cortex (model B), and precuneus (model C). Bayesian model comparison revealed Model C (GSW as autonomous input to precuneus), to be the best in 5 patients while model A prevailed in two cases. At the group level model C dominated and at the population-level the p value of model C was ∼1. Conclusion: Our results provide strong evidence that activity in the precuneus gates GSW discharges in the thalamo-(fronto) cortical network. This study is the first demonstration of a causal link between haemodynamic changes in the precuneus - an index of awareness - and the occurrence of pathological discharges in epilepsy. © 2009 Vaudano et al

The Emergence of Emotions

Emotion is conscious experience. It is the affective aspect of consciousness. Emotion arises from sensory stimulation and is typically accompanied by physiological and behavioral changes in the body. Hence an emotion is a complex reaction pattern consisting of three components: a physiological component, a behavioral component, and an experiential (conscious) component. The reactions making up an emotion determine what the emotion will be recognized as. Three processes are involved in generating an emotion: (1) identification of the emotional significance of a sensory stimulus, (2) production of an affective state (emotion), and (3) regulation of the affective state. Two opposing systems in the brain (the reward and punishment systems) establish an affective value or valence (stimulus-reinforcement association) for sensory stimulation. This is process (1), the first step in the generation of an emotion. Development of stimulus-reinforcement associations (affective valence) serves as the basis for emotion expression (process 2), conditioned emotion learning acquisition and expression, memory consolidation, reinforcement-expectations, decision-making, coping responses, and social behavior. The amygdala is critical for the representation of stimulus-reinforcement associations (both reward and punishment-based) for these functions. Three distinct and separate architectural and functional areas of the prefrontal cortex (dorsolateral prefrontal cortex, orbitofrontal cortex, anterior cingulate cortex) are involved in the regulation of emotion (process 3). The regulation of emotion by the prefrontal cortex consists of a positive feedback interaction between the prefrontal cortex and the inferior parietal cortex resulting in the nonlinear emergence of emotion. This positive feedback and nonlinear emergence represents a type of working memory (focal attention) by which perception is reorganized and rerepresented, becoming explicit, functional, and conscious. The explicit emotion states arising may be involved in the production of voluntary new or novel intentional (adaptive) behavior, especially social behavior

A Geographic Information Systems (GIS)-Based Approach to Derivative Map Production and Visualizing Bedrock Topography within the Town of Rutland, Vermont, USA

Many state and national geological surveys produce map products from surficial and bedrock geologic maps as a value-added deliverable for a variety of stakeholders. Improvements in powerful geostatistical exploratory tools and robust three-dimensional capabilities within geographic information systems (GIS) can facilitate the production of derivative products. In addition to providing access to geostatistical functions, many software packages are also capable of rendering three-dimensional visualizations using spatially distributed point data. A GIS-based approach using ESRI’s® Geostatistical Analyst® was used to create derivative maps depicting surficial overburden, bedrock topography, and potentiometric surface using well data and bedrock exposures. This methodology describes the importance and relevance of creating three-dimensional visualizations in tandem with traditional two-dimensional map products. These 3D products are especially useful for town managers and planners—often unfamiliar with interpreting two-dimensional geologic map products—so they can better visualize and understand the relationships between surficial overburden and potential groundwater resources

A GIS-based Methodology Toward Refining the Concept of Rural Food Deserts: A Case Study from Rutland County, Vermont

There is generally consensus regarding the methodology used to identify and visualize food deserts in urban centers, and to a lesser extent those in rural communities. The primary factor in food desert mapping, however, is distance to food provider without regard for the nutritional value of the food itself. The purpose of this paper is to offer a broader approach toward refining the food desert concept by incorporating a qualitative ranking of food providers based on the likelihood that they offer healthier food options. We apply this technique to Rutland County in rural Vermont by incorporating traditional grocery stores, supermarkets, big-box stores, general stores, and gas stations, and also including smaller food providers such as farmers' markets, co-ops, farm stands, and community supported agriculture operations. This approach could shift the methodology of identifying food deserts away from just using driving time and distance traveled to food providers meeting a minimum square footage. We propose a methodology that calculates distance to different types of food providers that also evaluates whether consumers have access to healthier food options

Un-packaging Manuscript Preparation and Review Guidelines for Curriculum and Instruction and Research Papers

In November 2015 the Journal of Geoscience Education Editorial Board met to review and discussed the criteria for curriculum and instruction (C&I) and Researchmanuscripts. The criteria are important for two primary reasons: these guide authors in manuscriptpreparation, and also serve as standards to which reviewers and editors evaluate manuscript content and organization. The criteria that the board examined were put in place in 2009 and consisted of a single document (i.e., webpage link). The categories of criteria were broadly applied to both Curriculum and Instruction and ResearchManuscripts, unless otherwise specially noted. These criteria helped make clear that all scholarly work in geoscience education that were to be considered for publication in JGE needed to be grounded in the literature, needed a well-defined purpose, and needed to include a description of the study setting and population. In addition, all papers needed to explain and justify the methods used, and describe the results. Importantly, it also required that conclusions must be evidence-based, and that the validity and reliability of the results be considered. Lastly, it required that the broader implications of the findings be discussed.The Editors and Associate Editors are in agreement that these fundamental manuscript expectations hold true today. However, based on their experience working with submitting authors and reviewers over the last several years, felt that authors and reviewers would benefit by un-packaging of the guidelines into separate documents for Curriculum and InstructionManuscripts and for ResearchManuscripts. Such a step has allowed us to make some important distinctions between these two types of papers, especially in terms of their purpose, study design, and methods, and allows us to provide clarifications and examples that are relevant to the each type of paper. In addition, we have added the expectation of a Limitations section to both types of papers. The outcomes of the criteria revision effort are provided below, and are also accessible online at nagt-jge.org under Author Information.The criteria should be used to guide both the content and organization of manuscripts. In addition, see the recently updated Manuscript Submission, Format, and Revision Instructions (nagt-jge.org under Author Information) which address submission and revision requirements, format guidelines, and offers technical advice