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Description

Rhodoferax antarcticus is an Antarctic purple nonsulfur bacterium and the only characterized anoxygenic phototroph that grows best below 20 °C. We present here a high-quality draft genome of Rfx. antarcticus strain ANT.BRT, isolated from an Antarctic microbial mat. The circular chromosome (3.8 Mbp) of Rfx. antarcticus has a 59.1% guanine

Rhodoferax antarcticus is an Antarctic purple nonsulfur bacterium and the only characterized anoxygenic phototroph that grows best below 20 °C. We present here a high-quality draft genome of Rfx. antarcticus strain ANT.BRT, isolated from an Antarctic microbial mat. The circular chromosome (3.8 Mbp) of Rfx. antarcticus has a 59.1% guanine + cytosine (GC) content and contains 4036 open reading frames. In addition, the bacterium contains a sizable plasmid (198.6 kbp, 48.4% GC with 226 open reading frames) that comprises about 5% of the total genetic content. Surprisingly, genes encoding light-harvesting complexes 1 and 3 (LH1 and LH3), but not light-harvesting complex 2 (LH2), were identified in the photosynthesis gene cluster of the Rfx. antarcticus genome, a feature that is unique among purple phototrophs. Consistent with physiological studies that showed a strong capacity for nitrogen fixation in Rfx. antarcticus, a nitrogen fixation gene cluster encoding a molybdenum-type nitrogenase was present, but no alternative nitrogenases were identified despite the cold-active phenotype of this phototroph. Genes encoding two forms of ribulose 1,5-bisphosphate carboxylase/oxygenase were present in the Rfx. antarcticus genome, a feature that likely provides autotrophic flexibility under varying environmental conditions. Lastly, genes for assembly of both type IV pili and flagella are present, with the latter showing an unusual degree of clustering. This report represents the first genomic analysis of a psychrophilic anoxygenic phototroph and provides a glimpse of the genetic basis for maintaining a phototrophic lifestyle in a permanently cold, yet highly variable, environment.

ContributorsBaker, Jennifer M. (Author) / Riester, Carli J. (Author) / Skinner, Blair M. (Author) / Newell, Austin W. (Author) / Swingley, Wesley D. (Author) / Madigan, Michael T. (Author) / Jung, Deborah O. (Author) / Asao, Marie (Author) / Chen, Min (Author) / Loughlin, Patrick C. (Author) / Pan, Hao (Author) / Lin, Yuankui (Author) / Li, Yaqiong (Author) / Shaw, Jacob (Author) / Prado, Mindy (Author) / Sherman, Chris (Author) / Kuo-Hsiang Tang, Joseph (Author) / Blankenship, Robert E. (Author) / Zhao, Tingting (Author) / Touchman, Jeffrey (Author) / Sattley, W. Matthew (Author) / College of Liberal Arts and Sciences (Contributor)
Created2017-02-21
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Description

The objective of the Indianapolis Flux Experiment (INFLUX) is to develop, evaluate and improve methods for measuring greenhouse gas (GHG) emissions from cities. INFLUX’s scientific objectives are to quantify CO2 and CH4 emission rates at 1 km2 resolution with a 10% or better accuracy and precision, to determine whole-city emissions

The objective of the Indianapolis Flux Experiment (INFLUX) is to develop, evaluate and improve methods for measuring greenhouse gas (GHG) emissions from cities. INFLUX’s scientific objectives are to quantify CO2 and CH4 emission rates at 1 km2 resolution with a 10% or better accuracy and precision, to determine whole-city emissions with similar skill, and to achieve high (weekly or finer) temporal resolution at both spatial resolutions. The experiment employs atmospheric GHG measurements from both towers and aircraft, atmospheric transport observations and models, and activity-based inventory products to quantify urban GHG emissions. Multiple, independent methods for estimating urban emissions are a central facet of our experimental design. INFLUX was initiated in 2010 and measurements and analyses are ongoing. To date we have quantified urban atmospheric GHG enhancements using aircraft and towers with measurements collected over multiple years, and have estimated whole-city CO2 and CH4 emissions using aircraft and tower GHG measurements, and inventory methods. Significant differences exist across methods; these differences have not yet been resolved; research to reduce uncertainties and reconcile these differences is underway. Sectorally- and spatially-resolved flux estimates, and detection of changes of fluxes over time, are also active research topics. Major challenges include developing methods for distinguishing anthropogenic from biogenic CO2 fluxes, improving our ability to interpret atmospheric GHG measurements close to urban GHG sources and across a broader range of atmospheric stability conditions, and quantifying uncertainties in inventory data products. INFLUX data and tools are intended to serve as an open resource and test bed for future investigations. Well-documented, public archival of data and methods is under development in support of this objective.

ContributorsDavis, Kenneth J. (Author) / Deng, Aijun (Author) / Lauvaux, Thomas (Author) / Miles, Natasha L. (Author) / Richardson, Scott J. (Author) / Sarmiento, Daniel P. (Author) / Gurney, Kevin (Author) / Hardesty, R. Michael (Author) / Bonin, Timothy A. (Author) / Brewer, W. Alan (Author) / Lamb, Brian K. (Author) / Shepson, Paul B. (Author) / Harvey, Rebecca M. (Author) / Cambaliza, Maria O. (Author) / Sweeney, Colm (Author) / Turnbull, Jocelyn C. (Author) / Whetstone, James (Author) / Karion, Anna (Author) / College of Liberal Arts and Sciences (Contributor)
Created2017-05-23
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Description

Dispositions of 286 engineering faculty members were assessed to determine views about three student-centered classroom strategies and how frequently faculty used those strategies. The student-centered classroom strategies examined were: using formative feedback to adjust instruction, integrating real-world applications, and promoting student-to-student discussions during formal class time. The Value, Expectancy, and

Dispositions of 286 engineering faculty members were assessed to determine views about three student-centered classroom strategies and how frequently faculty used those strategies. The student-centered classroom strategies examined were: using formative feedback to adjust instruction, integrating real-world applications, and promoting student-to-student discussions during formal class time. The Value, Expectancy, and Cost of Testing Educational Reforms Survey (VECTERS), based on expectancy theory, was designed, tested, and validated for this purpose. Results indicate using strategies, such as formative feedback, are significantly tied to perceived benefits and expectation of success. Using student-centered strategies is inversely related to the perceived cost of implementation – with more frequent users perceiving lower cost of time and materials.

ContributorsJudson, Eugene (Author) / Ross, Lydia (Author) / Middleton, James (Author) / Krause, Stephen (Author) / College of Liberal Arts and Sciences (Contributor)
Created2017-03-29
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Description

Quantifying greenhouse gas (GHG) emissions from cities is a key challenge towards effective emissions management. An inversion analysis from the INdianapolis FLUX experiment (INFLUX) project, as the first of its kind, has achieved a top-down emission estimate for a single city using CO2 data collected by the dense tower network

Quantifying greenhouse gas (GHG) emissions from cities is a key challenge towards effective emissions management. An inversion analysis from the INdianapolis FLUX experiment (INFLUX) project, as the first of its kind, has achieved a top-down emission estimate for a single city using CO2 data collected by the dense tower network deployed across the city. However, city-level emission data, used as a priori emissions, are also a key component in the atmospheric inversion framework. Currently, fine-grained emission inventories (EIs) able to resolve GHG city emissions at high spatial resolution, are only available for few major cities across the globe. Following the INFLUX inversion case with a global 1.1 km ODIAC fossil fuel CO2 emission dataset, we further improved the ODIAC emission field and examined its utility as a prior for the city scale inversion. We disaggregated the 1.1 km ODIAC non-point source emissions using geospatial datasets such as the global road network data and satellite-data driven surface imperviousness data to a 30 . 30 m resolution. We assessed the impact of the improved emission field on the inversion result, relative to priors in previous studies (Hestia and ODIAC). The posterior total emission estimate (5.1 MtC/yr) remains statistically similar to the previous estimate with ODIAC (5.3 MtC/yr). However, the distribution of the flux corrections was very close to those of Hestia inversion and the model-observation mismatches were significantly reduced both in forward and inverse runs, even without hourly temporal changes in emissions. EIs reported by cities often do not have estimates of spatial extents. Thus, emission disaggregation is a required step when verifying those reported emissions using atmospheric models. Our approach offers gridded emission estimates for global cities that could serves as a prior for inversion, even without locally reported EIs in a systematic way to support city-level Measuring, Reporting and Verification (MRV) practice implementation.

ContributorsOda, Tomohiro (Author) / Lauvaux, Thomas (Author) / Lu, Dengsheng (Author) / Rao, Preeti (Author) / Miles, Natasha L. (Author) / Richardson, Scott J. (Author) / Gurney, Kevin (Author) / College of Liberal Arts and Sciences (Contributor)
Created2017-06-14
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Description

Here we discuss the importance of using the rich and growing database of high-precision, audited radiocarbon dates for high-resolution bottom-up modelling to focus on problems concerning the spread of the Neolithic in the Iberia. We also compare the spread of the Late Mesolithic (so-called Geometric) and the Early Neolithic using

Here we discuss the importance of using the rich and growing database of high-precision, audited radiocarbon dates for high-resolution bottom-up modelling to focus on problems concerning the spread of the Neolithic in the Iberia. We also compare the spread of the Late Mesolithic (so-called Geometric) and the Early Neolithic using our modelling environment. Our results suggest that the source of radiocarbon data used to evaluate alternative hypotheses plays an important role in the results and open up new lines of research for the future.

ContributorsGordo, Salvador Pardo (Author) / Auban, Joan Bernabeu (Author) / Garcia Puchol, Oreto (Author) / Barton, Michael (Author) / Bergin, Sean (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015
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Description

We study the exclusive double-photon annihilation processes, e+e- → γγ* → γV0 and e+e- → γ*γ* → V[0 over a]V[0 over b], where the V[0 over i] is a neutral vector meson produced in the forward kinematical region: s >> −t and −t >> A[2 over QCD]. We show how

We study the exclusive double-photon annihilation processes, e+e- → γγ* → γV0 and e+e- → γ*γ* → V[0 over a]V[0 over b], where the V[0 over i] is a neutral vector meson produced in the forward kinematical region: s >> −t and −t >> A[2 over QCD]. We show how the differential cross sections [dσ over dt], as predicted by QCD, have additional falloff in the momentum transfer squared t due to the QCD compositeness of the hadrons, consistent with the leading-twist fixed-θCM scaling laws, both in terms of conventional Feynman diagrams and by using the AdS/QCD holographic model to obtain the results more transparently. However, even though they are exclusive channels and not associated with the conventional electron–positron annihilation process e+e- → γ* → q[bar over q], these total cross sections and σ(e+e- → γV0) and σ(e+e- → V[0 over a]V[0 over b]), integrated over the dominant forward- and backward-θCM angular domains, scale as 1/s, and thus contribute to the leading-twist scaling behavior of the ratio Re+e-. We generalize these results to exclusive double-electroweak vector-boson annihilation processes accompanied by the forward production of hadrons, such as e+e- → Z0V0 and e+e- → W-p+. These results can also be applied to the exclusive production of exotic hadrons such as tetraquarks, where the cross-section scaling behavior can reveal their multiquark nature.

ContributorsBrodsky, Stanley J. (Author) / Lebed, Richard (Author) / Lyubovitskij, Valery E. (Author) / College of Liberal Arts and Sciences (Contributor)
Created2016-11-17
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Description

Religion in society has been a complex study for both academic and non-academic disciplines. Defining religion had become an issue since the beginning of world religions. This issue will continue to remain in society, unless world religions avoid imposed definition of religion from the world religions’ perspective. This research aims

Religion in society has been a complex study for both academic and non-academic disciplines. Defining religion had become an issue since the beginning of world religions. This issue will continue to remain in society, unless world religions avoid imposed definition of religion from the world religions’ perspective. This research aims to study about how religion had been defined by many scholars theologically, politically, culturally, contextually, and how such different approaches never reach the consensus of understanding toward defining religion. In many cases, the definition of religion was imposed by scholars who have power of knowledge and intellectual in the discipline of world religions. The power of defining religion from the world religions’ perspective becomes challenging for people, such as indigenous people who continue to practice their religion from the origin of their fore-parents until today. Religion defined by world religions from the transcendental perspective had led to discrimination against other indigenous religions in various parts of the world, such as the Naga people in India.

ContributorsChuhwanglim, Lemwang (Author) / Wijaya, Yahya (Author) / Woodward, Mark (Author) / College of Liberal Arts and Sciences (Contributor)
Created2016-08-17
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Description

Normal function of the vestibulo-ocular reflex (VOR) coordinates eye movement with head movement, in order to provide clear vision during motion and maintain balance. VOR is generated within the semicircular canals of the inner ear to elicit compensatory eye movements, which maintain stability of images on the fovea during brief,

Normal function of the vestibulo-ocular reflex (VOR) coordinates eye movement with head movement, in order to provide clear vision during motion and maintain balance. VOR is generated within the semicircular canals of the inner ear to elicit compensatory eye movements, which maintain stability of images on the fovea during brief, rapid head motion, otherwise known as gaze stability. Normal VOR function is necessary in carrying out activities of daily living (eg, walking and riding in a car) and is of particular importance in higher demand activities (eg, sports-related activities). Disruption or damage in the VOR can result in symptoms such as movement-related dizziness, blurry vision, difficulty maintaining balance with head movements, and even nausea. Dizziness is one of the most common symptoms following traumatic brain injury (TBI) and is considered a risk factor for a prolonged recovery. Assessment of the vestibular system is of particular importance following TBI, in conjunction with oculomotor control, due to the intrinsic neural circuitry that exists between the ocular and vestibular systems. The purpose of this article is to review the physiology of the VOR and the visual-vestibular symptoms associated with TBI and to discuss assessment and treatment guidelines for TBI. Current challenges and future prospects will also be addressed.

ContributorsWallace, Bridgett (Author) / Lifshitz, Jonathan (Author) / College of Liberal Arts and Sciences (Contributor)
Created2016-02-17
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Description

Understanding how individual photoreceptor cells factor in the spectral sensitivity of a visual system is essential to explain how they contribute to the visual ecology of the animal in question. Existing methods that model the absorption of visual pigments use templates which correspond closely to data from thin cross-sections of

Understanding how individual photoreceptor cells factor in the spectral sensitivity of a visual system is essential to explain how they contribute to the visual ecology of the animal in question. Existing methods that model the absorption of visual pigments use templates which correspond closely to data from thin cross-sections of photoreceptor cells. However, few modeling approaches use a single framework to incorporate physical parameters of real photoreceptors, which can be fused, and can form vertical tiers. Akaike’s information criterion (AICc) was used here to select absorptance models of multiple classes of photoreceptor cells that maximize information, given visual system spectral sensitivity data obtained using extracellular electroretinograms and structural parameters obtained by histological methods. This framework was first used to select among alternative hypotheses of photoreceptor number. It identified spectral classes from a range of dark-adapted visual systems which have between one and four spectral photoreceptor classes. These were the velvet worm, Principapillatus hitoyensis, the branchiopod water flea, Daphnia magna, normal humans, and humans with enhanced S-cone syndrome, a condition in which S-cone frequency is increased due to mutations in a transcription factor that controls photoreceptor expression. Data from the Asian swallowtail, Papilio xuthus, which has at least five main spectral photoreceptor classes in its compound eyes, were included to illustrate potential effects of model over-simplification on multi-model inference. The multi-model framework was then used with parameters of spectral photoreceptor classes and the structural photoreceptor array kept constant. The goal was to map relative opsin expression to visual pigment concentration. It identified relative opsin expression differences for two populations of the bluefin killifish, Lucania goodei. The modeling approach presented here will be useful in selecting the most likely alternative hypotheses of opsin-based spectral photoreceptor classes, using relative opsin expression and extracellular electroretinography.

ContributorsLessios, Nicolas (Author) / College of Liberal Arts and Sciences (Contributor)
Created2017-07-21
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Description

Human milk contains essential micronutrients for growth and development during early life. Environmental pollutants, such as potentially toxic metals, can also be transferred to the infant through human milk. These elements have been well-studied, but changing diets and environments and advances in laboratory technology require re-examining these elements in a

Human milk contains essential micronutrients for growth and development during early life. Environmental pollutants, such as potentially toxic metals, can also be transferred to the infant through human milk. These elements have been well-studied, but changing diets and environments and advances in laboratory technology require re-examining these elements in a variety of settings. The aim of this study was to characterize the concentrations of essential and toxic metals in human milk from four diverse populations. Human milk samples (n = 70) were collected in Argentina (n = 21), Namibia (n = 6), Poland (n = 23), and the United States (n = 20) using a standardized mid-feed collection procedure. Milk concentrations of calcium, zinc, iron, copper, manganese, lead, arsenic, and cadmium were determined using inductively coupled plasma mass spectrometry (ICP-MS). We used standard multiple linear regression models to evaluate differences among populations, while including infant age, infant sex, and maternal parity status (multiparous or primiparous) as covariates. Concentrations of all elements, except zinc, varied across populations after controlling for infant age, infant sex, and maternal parity. Calcium and magnesium showed more differences across populations than iron or copper. There were no significant differences among population in zinc concentrations. Mean concentrations of lead, but not arsenic, were low compared to recently published values from other populations. The concentrations of trace elements in human milk are variable among populations. Limitations due to small sample sizes and environmental contamination of some samples prevent us from drawing robust conclusions about the causes of these differences.

ContributorsKlein, Laura D. (Author) / Breakey, Alicia A. (Author) / Scelza, Brooke (Author) / Valeggia, Claudia (Author) / Jasienska, Grazyna (Author) / Hinde, Katie (Author) / College of Liberal Arts and Sciences (Contributor)
Created2017-08-17