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Showing papers by "Boise State University published in 2010"


Journal ArticleDOI
TL;DR: A broad compilation of modern carbon isotope compositions in all C3 plant types shows a monotonic increase in δ13C with decreasing mean annual precipitation (MAP) that differs from previous models, allowing refined interpretation of MAP, paleodiet, and paleoecology of ecosystems dominated by C3 plants, either prior to 7–8 million years ago (Ma), or more recently at mid- to high latitudes.
Abstract: A broad compilation of modern carbon isotope compositions in all C3 plant types shows a monotonic increase in δ13C with decreasing mean annual precipitation (MAP) that differs from previous models. Corrections for temperature, altitude, or latitude are smaller than previously estimated. As corrected for altitude, latitude, and the δ13C of atmospheric CO2, these data permit refined interpretation of MAP, paleodiet, and paleoecology of ecosystems dominated by C3 plants, either prior to 7–8 million years ago (Ma), or more recently at mid- to high latitudes. Twenty-nine published paleontological studies suggest preservational or scientific bias toward dry ecosystems, although wet ecosystems are also represented. Unambiguous isotopic evidence for C4 plants is lacking prior to 7–8 Ma, and hominid ecosystems at 4.4 Ma show no isotopic evidence for dense forests. Consideration of global plant biomass indicates that average δ13C of C3 plants is commonly overestimated by approximately 2‰.

1,051 citations


Journal ArticleDOI
TL;DR: Through a better understanding of the mechanisms of action and cellular consequences resulting from nanoparticles interactions with cells, the inherent toxicity and selectivity of ZnO nanoparticles against cancer may be improved further to make them attractive new anticancer agents.
Abstract: Importance of the field: Metal oxide nanoparticles, including zinc oxide, are versatile platforms for biomedical applications and therapeutic intervention. There is an urgent need to develop new classes of anticancer agents, and recent studies demonstrate that ZnO nanomaterials hold considerable promise.Areas covered in this review: This review analyzes the biomedical applications of metal oxide and ZnO nanomaterials under development at the experimental, preclinical and clinical levels. A discussion regarding the advantages, approaches and limitations surrounding the use of metal oxide nanoparticles for cancer applications and drug delivery is presented. The scope of this article is focused on ZnO, and other metal oxide nanomaterial systems, and their proposed mechanisms of cytotoxic action, as well as current approaches to improve their targeting and cytotoxicity against cancer cells.What the reader will gain: This review aims to give an overview of ZnO nanomaterials in biomedical applications.Take home...

985 citations


Journal ArticleDOI
Markus Ackermann1, Marco Ajello1, Alice Allafort1, Elisa Antolini2  +211 moreInstitutions (40)
TL;DR: The second catalog of active galactic nuclei (AGNs) detected by the Fermi Large Area Telescope (LAT) in two years of scientific operation is presented in this article, which includes 1017 γ-ray sources located at high Galactic latitudes (|b| > 10°) that are detected with a test statistic (TS) greater than 25 and associated statistically with AGNs.
Abstract: The second catalog of active galactic nuclei (AGNs) detected by the Fermi Large Area Telescope (LAT) in two years of scientific operation is presented. The second LAT AGN catalog (2LAC) includes 1017 γ-ray sources located at high Galactic latitudes (|b| > 10°) that are detected with a test statistic (TS) greater than 25 and associated statistically with AGNs. However, some of these are affected by analysis issues and some are associated with multiple AGNs. Consequently, we define a Clean Sample which includes 886 AGNs, comprising 395 BL Lacertae objects (BL Lac objects), 310 flat-spectrum radio quasars (FSRQs), 157 candidate blazars of unknown type (i.e., with broadband blazar characteristics but with no optical spectral measurement yet), 8 misaligned AGNs, 4 narrow-line Seyfert 1 (NLS1s), 10 AGNs of other types, and 2 starburst galaxies. Where possible, the blazars have been further classified based on their spectral energy distributions (SEDs) as archival radio, optical, and X-ray data permit. While almost all FSRQs have a synchrotron-peak frequency 1015 Hz. The 2LAC represents a significant improvement relative to the first LAT AGN catalog (1LAC), with 52% more associated sources. The full characterization of the newly detected sources will require more broadband data. Various properties, such as γ-ray fluxes and photon power-law spectral indices, redshifts, γ-ray luminosities, variability, and archival radio luminosities and their correlations are presented and discussed for the different blazar classes. The general trends observed in 1LAC are confirmed.

981 citations


Journal ArticleDOI
19 Mar 2010-Science
TL;DR: This article found that participation in a world religion is associated with fairness, although not across all measures, and that market integration positively correlates with fairness while community size positively covaries with punishment.
Abstract: Large-scale societies in which strangers regularly engage in mutually beneficial transactions are puzzling. The evolutionary mechanisms associated with kinship and reciprocity, which underpin much of primate sociality, do not readily extend to large unrelated groups. Theory suggests that the evolution of such societies may have required norms and institutions that sustain fairness in ephemeral exchanges. If that is true, then engagement in larger-scale institutions, such as markets and world religions, should be associated with greater fairness, and larger communities should punish unfairness more. Using three behavioral experiments administered across 15 diverse populations, we show that market integration (measured as the percentage of purchased calories) positively covaries with fairness while community size positively covaries with punishment. Participation in a world religion is associated with fairness, although not across all measures. These results suggest that modern prosociality is not solely the product of an innate psychology, but also reflects norms and institutions that have emerged over the course of human history.

884 citations


Journal ArticleDOI
05 Mar 2010-Science
TL;DR: Four high-precision U-Pb ages for Neoproterozoic rocks in northwestern Canada are presented that constrain large perturbations in the carbon cycle, a major diversification and depletion in the microfossil record, and the onset of the Sturtian glaciation.
Abstract: The Neoproterozoic was an era of great environmental and biological change, but a paucity of direct and precise age constraints on strata from this time has prevented the complete integration of these records. We present four high-precision U-Pb ages for Neoproterozoic rocks in northwestern Canada that constrain large perturbations in the carbon cycle, a major diversification and depletion in the microfossil record, and the onset of the Sturtian glaciation. A volcanic tuff interbedded with Sturtian glacial deposits, dated at 716.5 million years ago, is synchronous with the age of the Franklin large igneous province and paleomagnetic poles that pin Laurentia to an equatorial position. Ice was therefore grounded below sea level at very low paleolatitudes, which implies that the Sturtian glaciation was global in extent.

499 citations


Journal ArticleDOI
TL;DR: The background of GPS techniques that have been used to gather data for wildlife studies is provided, and alternatives for storing and retrieving data by using dataloggers, radio-frequency download systems, and potential new data recovery technologies are presented.
Abstract: Biologists can equip animals with global positioning system (GPS) technology to obtain accurate (less than or equal to 30 m) locations that can be combined with sensor data to study animal behaviour and ecology. We provide the background of GPS techniques that have been used to gather data for wildlife studies. We review how GPS has been integrated into functional systems with data storage, data transfer, power supplies, packaging and sensor technologies to collect temperature, activity, proximity and mortality data from terrestrial species and birds. GPS ‘rapid fixing’ technologies combined with sensors provide location, dive frequency and duration profiles, and underwater acoustic information for the study of marine species. We examine how these rapid fixing technologies may be applied to terrestrial and avian applications. We discuss positional data quality and the capability for high-frequency sampling associated with GPS locations. We present alternatives for storing and retrieving data by using dataloggers (biologging), radio-frequency download systems (e.g. very high frequency, spread spectrum), integration of GPS with other satellite systems (e.g. Argos, Globalstar) and potential new data recovery technologies (e.g. network nodes). GPS is one component among many rapidly evolving technologies. Therefore, we recommend that users and suppliers interact to ensure the availability of appropriate equipment to meet animal research objectives.

431 citations


Journal ArticleDOI
TL;DR: Results underscore that labile soil C inputs can regulate decomposition of more recalcitrant soil C by controlling the activity and relative abundance of fungi and bacteria.
Abstract: Summary • Root carbon (C) inputs may regulate decomposition rates in soil, and in this study we ask: how do labile C inputs regulate decomposition of plant residues, and soil microbial communities? • In a 14 d laboratory incubation, we added C compounds often found in root exudates in seven different concentrations (0, 0.7, 1.4, 3.6, 7.2, 14.4 and 21.7 mg C g )1 soil) to soils amended with and without 13 C-labeled plant residue. We measured CO2 respiration and shifts in relative fungal and bacterial rRNA gene copy numbers using quantitative polymerase chain reaction (qPCR). • Increased labile C input enhanced total C respiration, but only addition of C at low concentrations (0.7 mg C g )1 ) stimulated plant residue decomposition (+2%). Intermediate concentrations (1.4, 3.6 mg C g )1 ) had no impact on plant residue decomposition, while greater concentrations of C (> 7.2 mg C g )1 ) reduced decomposition ()50%). Concurrently, high exudate concentrations (> 3.6 mg C g )1 ) increased fungal and bacterial gene copy numbers, whereas low exudate concentrations (< 3.6 mg C g )1 ) increased metabolic activity rather than gene copy numbers. • These results underscore that labile soil C inputs can regulate decomposition of more recalcitrant soil C by controlling the activity and relative abundance of fungi and bacteria.

365 citations


Journal ArticleDOI
12 Nov 2010-Science
TL;DR: Palynology shows that the tropical rainforest was able to persist under elevated temperatures and high levels of atmospheric carbon dioxide, in contrast to speculations that tropical ecosystems were severely compromised by heat stress.
Abstract: Temperatures in tropical regions are estimated to have increased by 3° to 5°C, compared with Late Paleocene values, during the Paleocene-Eocene Thermal Maximum (PETM, 56.3 million years ago) event. We investigated the tropical forest response to this rapid warming by evaluating the palynological record of three stratigraphic sections in eastern Colombia and western Venezuela. We observed a rapid and distinct increase in plant diversity and origination rates, with a set of new taxa, mostly angiosperms, added to the existing stock of low-diversity Paleocene flora. There is no evidence for enhanced aridity in the northern Neotropics. The tropical rainforest was able to persist under elevated temperatures and high levels of atmospheric carbon dioxide, in contrast to speculations that tropical ecosystems were severely compromised by heat stress.

270 citations


Journal ArticleDOI
TL;DR: In this paper, high-precision ID-TIMS U-Pb zircon ages for 12 interstratified tuffs and tonsteins are used to radiometrically calibrate the detailed lithostratigraphic, cyclostrithmographic, and biostrigraphic framework of the Carboniferous Donets Basin of eastern Europe.
Abstract: [1] High-precision ID-TIMS U-Pb zircon ages for 12 interstratified tuffs and tonsteins are used to radiometrically calibrate the detailed lithostratigraphic, cyclostratigraphic, and biostratigraphic framework of the Carboniferous Donets Basin of eastern Europe. Chemical abrasion of zircons, use of the internationally calibrated EARTHTIME mixed U-Pb isotope dilution tracer, and improved mass spectrometry guided by detailed error analysis have resulted in an age resolution of <0.05%, or ∼100 ka, for these Carboniferous volcanics. This precision allows the resolution of time in the Milankovitch band and confirms the long-standing hypothesis that individual high-frequency Pennsylvanian cyclothems and bundles of cyclothems into fourth-order sequences are the eustatic response to orbital eccentricity (∼100 and 400 ka) forcing. Tuning of the fourth-order sequences in the Donets Basin to the long-period eccentricity cycle results in a continuous age model for the Middle to Late Pennsylvanian (Moscovian-Kasimovian-Ghzelian) strata of the basin and their record of biological and climatic changes through the latter portion of the late Paleozoic Ice Age. Detailed fusulinid and conodont zonations allow the export of this age model to sections throughout Euramerica. Additional ages for Mississippian strata provide among the first robust radiometric calibration points within this subperiod and result in variable lowering of the base ages of its constituent stages compared to recent global time scale compilations.

236 citations


Journal ArticleDOI
TL;DR: To fabricate quantum dot arrays with programmable periodicity, functionalized DNA origami nanotubes were developed and showed precise, programmable, large-scale nanoparticle patterning; however, limitations in array periodicity were also observed.
Abstract: To fabricate quantum dot arrays with programmable periodicity, functionalized DNA origami nanotubes were developed. Selected DNA staple strands were biotin-labeled to form periodic binding sites for streptavidin-conjugated quantum dots. Successful formation of arrays with periods of 43 and 71 nm demonstrates precise, programmable, large-scale nanoparticle patterning; however, limitations in array periodicity were also observed. Statistical analysis of AFM images revealed evidence for steric hindrance or site bridging that limited the minimum array periodicity.

231 citations


Journal ArticleDOI
TL;DR: In this paper, the authors show that over the past several decades, geomorphic processes in the Arctic have been changing or intensifying due to global warming and that lakes, ponds, and wetlands appear to be more dynamic, growing in some areas, shrinking in others, and changing distribution across lowland regions.
Abstract: Observations indicate that over the past several decades, geomorphic processes in the Arctic have been changing or intensifying. Coastal erosion, which currently supplies most of the sediment and carbon to the Arctic Ocean [Rachold et al., 2000], may have doubled since 1955 [Mars and Houseknecht, 2007]. Further inland, expansion of channel networks [Toniolo et al., 2009] and increased river bank erosion [Costard et al., 2007] have been attributed to warming. Lakes, ponds, and wetlands appear to be more dynamic, growing in some areas, shrinking in others, and changing distribution across lowland regions [e.g., Smith et al., 2005]. On the Arctic coastal plain, recent degradation of frozen ground previously stable for thousands of years suggests 10–30% of lowland and tundra landscapes may be affected by even modest warming [Jorgenson et al., 2006]. In headwater regions, hillslope soil erosion and landslides are increasing [e.g., Gooseff et al., 2009].

Journal ArticleDOI
TL;DR: All SrTiO3 films and bulk crystals are relaxor ferroelectrics, and the role of strain is to stabilize longer-range correlation of preexisting nanopolar regions, likely originating from minute amounts of unintentional Sr deficiency in nominally stoichiometric samples.
Abstract: Biaxial strain is known to induce ferroelectricity in thin films of nominally nonferroelectric materials such as SrTiO3. By a direct comparison of the strained and strain-free SrTiO3 films using dielectric, ferroelectric, Raman, nonlinear optical and nanoscale piezoelectric property measurements, we conclude that all SrTiO3 films and bulk crystals are relaxor ferroelectrics, and the role of strain is to stabilize longer-range correlation of preexisting nanopolar regions, likely originating from minute amounts of unintentional Sr deficiency in nominally stoichiometric samples. These findings highlight the sensitive role of stoichiometry when exploring strain and epitaxy-induced electronic phenomena in oxide films, heterostructures, and interfaces.

Journal ArticleDOI
TL;DR: In this article, a mixed methods design was used to identify factors associated with motivational engagement in video gaming self-report instruments were administered to 189 video game players to assess goal orientations, affect, need for cognition, and perceptions of engagement and flow Simultaneously, a sub-set of 25 participants were interviewed and results analyzed to identify patterns that influenced their propensity for gaming.
Abstract: A mixed methods design was used to identify factors associated with motivational engagement in video gaming Self-report instruments were administered to 189 video game players to assess goal orientations, affect, need for cognition, and perceptions of engagement and flow Simultaneously, a sub-set of 25 participants were interviewed and results analyzed to identify patterns that influenced their propensity for gaming Regression results revealed motivational engagement for gaming was related to gender, hours of play, task orientation, and socialization Players indicated that gaming was socially captivating, fun, challenging but relaxing, and precipitated positive affect and cognition even when unsuccessful results were achieved The negative consequences normally associated with task failure were not reported by participants to take place during gaming We concluded transfer of motivational engagement in gaming for entertainment to educational contexts was unlikely to occur

Journal ArticleDOI
TL;DR: In this paper, the duration and geographic extent of Carboniferous glacial events in southern Gondwana remain poorly constrained despite recent evidence for a more dynamic glacial history than previously considered.
Abstract: The duration and geographic extent of Carboniferous glacial events in southern Gondwana remain poorly constrained despite recent evidence for a more dynamic glacial history than previously considered. We report 10 high-precision (2! ± <0.1%) U-Pb ages for the Permian-Carboniferous Paganzo Group, NW Argentina, that redefi ne the chronostratigraphy of the late Paleozoic Paganzo and Rio Blanco Basins, and signifi cantly refi ne the timing of glacial events and climate shifts in the western region of southern Gondwana. Radiometric calibration of the Paganzo Group indicates three pulses of Carboniferous glaciation in the mid-Visean, the late Serpukhovian to earliest Bashkirian, and between the latest Bashkirian to early Moscovian. An abrupt shift in depositional style from high-sinuosity single-storied fl uvial deposits and clay-rich paleosols to low-sinuosity multi storied feldspathic fluvial deposits inter calated with eolianites and calcic paleosols is constrained to the latest Moscovian and earliest Kasimovian. These constraints indicate a relatively abrupt climate shift from humid-subhumid to nonseasonal semiarid regional climate conditions that occurred signifi cantly earlier than previously inferred (Early Permian). This period of high-latitude aridity was contemporaneous with a shift to dryland depositional environments and a major vegetation regime shift documented throughout the Pangean paleotropics in the Pennsylvanian.

Journal ArticleDOI
TL;DR: The lower Lesser Himalayan sequence marks the northern extremity of the exposed Indian plate, and is generally interpreted as a passive margin this paper, however, five lines of evidence collectively suggest a continental arc setting: (1) igneous intrusions and volcanic rocks occur at this stratigraphic level across the length of the Himalaya, (2) ages of intrusive and metavolcanic (?) rocks cluster at 1780-1880 Ma but also indicate a long-lived igneous process, (3) detrital zircon ages in clastic rocks
Abstract: The lower Lesser Himalayan sequence marks the northern extremity of the exposed Indian plate, and is generally interpreted as a passive margin. Five lines of evidence, however, collectively suggest a continental arc setting: (1) igneous intrusions and volcanic rocks occur at this stratigraphic level across the length of the Himalaya, (2) ages of intrusive and metavolcanic (?) rocks cluster at 1780–1880 Ma but also indicate a long-lived igneous process, (3) detrital zircon ages in clastic rocks cluster at 1800–1900 Ma, with a unimodal age distribution in some rocks, (4) the mineralogy and chemistry of metasedimentary rocks differ from typical shales and suggest a volcanogenic source, (5) trace-element chemistries of orthogneisses and metabasalts are more consistent with either an arc or a collisional setting. Intercalation of volcanic rocks with clastic sediments and a general absence of Proterozoic metamorphic ages do not support a collisional origin. An arc model further underscores the profound unconformity separating lower-upper Lesser Himalayan rocks, indicating that a Paleoproterozoic arc may have formed the stratigraphic base of the northern Indian margin. This, in turn, may indicate disposition of the Indian plate adjacent to North America in the ca. 1800 Ma supercontinent Columbia. Felsic orthogneisses (“Ulleri”) likely represent shallow intrusions, not Indian basement.

Proceedings ArticleDOI
04 Jan 2010
TL;DR: This study pursues mixed MPI-CUDA implementations and investigates three strategies to probe the efficiency and scalability of incompressible flow computations on the Lincoln Tesla cluster at the National Center for Supercomputing Applications (NCSA).
Abstract: Modern graphics processing units (GPUs) with many-core architectures have emerged as general-purpose parallel computing platforms that can accelerate simulation science applications tremendously. While multiGPU workstations with several TeraFLOPS of peak computing power are available to accelerate computational problems, larger problems require even more resources. Conventional clusters of central processing units (CPU) are now being augmented with multiple GPUs in each compute-node to tackle large problems. The heterogeneous architecture of a multi-GPU cluster with a deep memory hierarchy creates unique challenges in developing scalable and efficient simulation codes. In this study, we pursue mixed MPI-CUDA implementations and investigate three strategies to probe the efficiency and scalability of incompressible flow computations on the Lincoln Tesla cluster at the National Center for Supercomputing Applications (NCSA). We exploit some of the advanced features of MPI and CUDA programming to overlap both GPU data transfer and MPI communications with computations on the GPU. We sustain approximately 2.4 TeraFLOPS on the 64 nodes of the NCSA Lincoln Tesla cluster using 128 GPUs with a total of 30,720 processing elements. Our results demonstrate that multi-GPU clusters can substantially accelerate computational fluid dynamics (CFD) simulations.

Journal ArticleDOI
TL;DR: In this article, the authors developed a model of commitment-gaining success that is based on intra-organizational influence theory, which includes project payback, customer pressure, government regulation, top management support and the project champion's position in the organizational hierarchy.

Journal ArticleDOI
TL;DR: Changing walking mechanics and muscle coordination patterns to utilize muscle groups that perform the same biomechanical function, yet contribute less to the knee joint forces may be an effective way to reduce knee joint loading during walking.

Journal ArticleDOI
TL;DR: This is the first known study to investigate the perceptions of 126 academic nurse leaders (deans, directors, and chairpersons) from 128 associate degree in nursing and bachelor of science nursing programs in a large western state about academic incivility.
Abstract: Academic incivility is disruptive behavior that substantially or repeatedly interferes with teaching and learning. Incivility on college campuses jeopardizes the welfare of all members of the academy. Academic nurse leaders play a critical role in preventing and addressing academic incivility because these behaviors can negatively affect learning and harm faculty-student relationships. Although studies on student and faculty incivility have been conducted in nursing education, there are no known studies regarding the perceptions of academic nurse leaders about this problem. This is the first known study to investigate the perceptions of 126 academic nurse leaders (deans, directors, and chairpersons) from 128 associate degree in nursing and bachelor of science nursing programs in a large western state. Academic nurse leaders responded to five open-ended questions regarding their perceptions of stressors that affect nursing faculty and students, the uncivil behaviors exhibited by both groups, and the role of leadership in preventing and addressing incivility in nursing education.

Journal ArticleDOI
TL;DR: This article explored the cues that both at-risk and typical college readers use as a basis for their metacomprehension judgments in the context of a delayed-summarization paradigm.
Abstract: Two studies attempt to determine the causes of poor metacomprehension accuracy and then, in turn, to identify interventions that circumvent these difficulties to support effective comprehension monitoring performance. The first study explored the cues that both at-risk and typical college readers use as a basis for their metacomprehension judgments in the context of a delayed-summarization paradigm. Improvement was seen in all readers, but at-risk readers did not reach the same level of metacomprehension accuracy as a sample of typical college readers. Further, whereas few readers reported using comprehension-related cues, more at-risk readers reported using surface-related cues as the basis for their judgments. To support the use of more predictive cues among the at-risk readers, a second study employed a concept-map intervention, which was intended to make situation-model level representations more salient. Concept mapping improved both the comprehension and metacomprehension accuracy of at-risk readers...

Journal ArticleDOI
TL;DR: In this article, the authors assess whether the adoption of a participatory budgeting (PB) program is associated with changes in social spending or changes in several indicators of well-being, finding that PB municipalities spend a slightly higher share of their budget on health and education programs, but there is little evidence that this shift in budget priorities affects measurable outcomes.

Journal ArticleDOI
TL;DR: Examination of young adults' use of social media websites to post public images and videos of themselves depicting alcohol consumption, inebriated behavior, or recreational marijuana use revealed that the majority of image and video representations of alcohol consumption depicted females in social gatherings while images of marijuana use depicted solitary males.

Journal ArticleDOI
16 Mar 2010-Langmuir
TL;DR: It is concluded that controlling the electrostatic attraction between nanoparticles and their cellular targets may permit the modulation of nanoparticle cytotoxicity.
Abstract: Nanoscale materials can have cytotoxic effects. Here we present the first combined empirical and theoretical investigation of the influence of electrostatic attraction on nanoparticle cytotoxicity. Modeling electrostatic interactions between cells and 13 nm spheres of zinc oxide nanoparticles provided insight into empirically determined variations of the minimum inhibitory concentrations between four differently charged isogenic strains of Pseudomonas aeruginosa PAO1. We conclude that controlling the electrostatic attraction between nanoparticles and their cellular targets may permit the modulation of nanoparticle cytotoxicity.

Journal ArticleDOI
TL;DR: In this paper, finite element models are used to simulate deformation caused by mass extraction from a magma reservoir that is surrounded by a viscoelastic rind of country rock embedded in an elastic domain that is partitioned to account for the weak caldera materials observed with tomography.
Abstract: [1] Interferometric synthetic aperture radar (InSAR) data indicate that the caldera of Okmok volcano, Alaska, subsided more than a meter during its eruption in 1997. The large deformation suggests a relatively shallow magma reservoir beneath Okmok. Seismic tomography using ambient ocean noise reveals two low-velocity zones (LVZs). The shallow LVZ corresponds to a region of weak, fluid-saturated materials within the caldera and extends from the caldera surface to a depth of 2 km. The deep LVZ clearly indicates the presence of the magma reservoir beneath Okmok that is significantly deeper (>4 km depth) compared to previous geodetic-based estimates (3 km depth). The deep LVZ associated with the magma reservoir suggests magma remains in a molten state between eruptions. We construct finite element models (FEMs) to simulate deformation caused by mass extraction from a magma reservoir that is surrounded by a viscoelastic rind of country rock embedded in an elastic domain that is partitioned to account for the weak caldera materials observed with tomography. This configuration allows us to reduce the estimated magma reservoir depressurization to within lithostatic constraints, while simultaneously maintaining the magnitude of deformation required to predict the InSAR data. More precisely, the InSAR data are best predicted by an FEM simulating a rind viscosity of 7.5 × 1016 Pa s and a mass flux of −4.2 × 109 kg/d from the magma reservoir. The shallow weak layer within the caldera provides a coeruption stress regime and neutral buoyancy horizon that support lateral magma propagation from the central magma reservoir to extrusion near the rim of the caldera.

Journal ArticleDOI
TL;DR: In this article, a meta-analysis of 32 studies was conducted to examine the cognitive processing differences between students with SLD and typically achieving peers, and the analysis found moderately large to large effect sizes in cognitive processes differences between groups of students with learning disabilities and typically-achieving students.
Abstract: Many practitioners and state education agency staff would likely agree that the accuracy and consistency of specific learning disability (SLD) eligibility decisions is in need of improvement. One component of the SLD definition particularly controversial in the identification procedures is the evaluation of cognitive processes, primarily due to a lack of information about the role they might play in informing an SLD diagnosis and eligi bility for special education services. A meta-analysis of 32 studies was conducted to examine the cognitive processing differences between students with SLD and typically achieving peers. The analysis found moderately large to large effect sizes in cognitive processing differences between groups of students with SLD and typically achieving students. These differences are of sufficient magnitude to justify including measures of cognitive processing ability in the evaluation and identification of SLD.

Proceedings ArticleDOI
18 Jul 2010
TL;DR: Two-terminal chalcogenide-based devices containing Ge2Se3 and Ag that function as memristors that are electrically characterized at room temperature using quasi-static DC methods, AC sinusoidal methods, and AC pulse testing methods exhibit memristive behavior.
Abstract: We have fabricated two-terminal chalcogenide-based devices containing Ge 2 Se 3 and Ag that function as memristors. These devices have been electrically characterized at room temperature using quasi-static DC methods, AC sinusoidal methods, and AC pulse testing methods. In all cases, the devices exhibit memristive behavior.

Journal ArticleDOI
01 Aug 2010
TL;DR: In this paper, two uppermost Carboniferous-Lower Triassic fluvial-lacustrine sections in the Tarlong-Taodonggou half-graben, southern Bogda Mountains, NW China, comprise a 1834m-thick, relatively complete sedimentary and paleoclimatic record of the east coast of mid-latitude NE Pangea.
Abstract: Two uppermost Carboniferous–Lower Triassic fluvial–lacustrine sections in the Tarlong–Taodonggou half-graben, southern Bogda Mountains, NW China, comprise a 1834 m-thick, relatively complete sedimentary and paleoclimatic record of the east coast of mid-latitude NE Pangea. Depositional environmental interpretations identified three orders (high, intermediate, and low) of sedimentary cycles. High-order cycles (HCs) have five basic types, including fluvial cycles recording repetitive changes of erosion and deposition and lacustrine cycles recording repetitive environmental changes associated with lake expansion and contraction. HCs are grouped into intermediate-order cycles (ICs) on the basis of systematic changes of thickness, type, and component lithofacies of HCs. Nine low-order cycles (LCs) are demarcated by graben-wide surfaces across which significant long-term environmental changes occurred. A preliminary cyclostratigraphic framework provides a foundation for future studies of terrestrial climate, tectonics, and paleontology in mid-latitude NE Pangea. Climate variabilities at the intra-HC, HC, IC, and LC scales were interpreted from sedimentary and paleosol evidence. Four prominent climatic shifts are present: 1) from the humid–subhumid to highly-variable subhumid–semiarid conditions at the beginning of Sakamarian; 2) from highly-variable subhumid–semiarid to humid–subhumid conditions across the Artinskian-Capitanian unconformity; 3) from humid–subhumid to highly-variable subhumid–semiarid conditions at early Induan; and 4) from the highly-variable subhumid–semiarid to humid–subhumid conditions across the Olenekian-Anisian unconformity. The stable humid–subhumid condition from Lopingian to early Induan implies that paleoclimate change may not have been the cause of the end-Permian terrestrial mass extinction. A close documentation of the pace and timing of the extinction and exploration of other causes are needed. In addition, the semiarid–subhumid conditions from Sakamarian to Artinskian–Kungurian (?) and from middle Induan to end of Olenekian are in conflict with modern mid-latitude east coast meso- and macrothermal humid climate. Extreme continentality, regional orographic effect, and/or abnormal circulation of Paleo-Tethys maybe are possible causes. Our work serves as a rare data point at mid-latitude NE Pangea for climate modeling to seek explanations on the origin(s) of climate variability in NE Pangea from latest Carboniferous to Early Triassic.

Journal ArticleDOI
TL;DR: In this article, a strictly periodic twin pattern containing periodic disclination walls with optimally screened stress fields is considered, and a discontinuity of the fraction of secondary twins is introduced and modeled as a disclination dipole.

Journal ArticleDOI
TL;DR: The role of caspases in AD will be addressed, including recent studies utilizing in vivo transgenic mouse models of tauopathies, and a discussion of the therapeutic value and dangers of targeting caspase inhibition in the treatment of AD using casp enzyme inhibitors such as Q-VD-OPh will be evaluated.
Abstract: Although apoptosis plays a critical role in molding the CNS into its final appearance and function, inappropriate activation of this pathway in the aging brain may contribute to neurodegeneration. In Alzheimer’s disease (AD), an overwhelming body of evidence supports the activation of apoptosis in general, and caspases specifically as an early event that may not only contribute to neurodegeneration but also promote the underlying pathology associated with this disease. Therefore, caspase inhibitors may provide an effective strategy for treating AD. However, despite the compelling evidence indicating a role for caspases in disease progression, chronic treatment with caspase inhibitors in animal models of AD has never been undertaken. In this review the role of caspases in AD will be addressed, including recent studies utilizing in vivo transgenic mouse models of tauopathies. In addition, a discussion of the therapeutic value and dangers of targeting caspase inhibition in the treatment of AD using caspase inhibitors such as Q-VD-OPh will be evaluated.

Journal ArticleDOI
TL;DR: In this paper, the authors investigated the impacts of tree encroachment on runoff and erosion processes at two woodland sites in the Intermountain West, USA and found that the overall hydrologic vulnerability of sagebrush steppe following woodland encroachment depends on the potential influence of tree dominance on bare intercanopy expanse and connectivity.