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The North American Carbon Program Multi-Scale Synthesis And Terrestrial Model Intercomparison Project – Part 2: Environmental Driver Data, Y. Wei, S. Liu, D. N. Huntzinger, A. M. Michalak, N. Viovy, W. M. Post, C. R. Schwalm, K. Schaefer, A. R. Jacobson, Chaoqun (Crystal) Lu, Hanqin Tian, D. M. Ricciuto, R. B. Cook, J. Mao, X. Shi

Chaoqun (Crystal) Lu

Ecosystems are important and dynamic components of the global carbon cycle, and terrestrial biospheric models (TBMs) are crucial tools in further understanding of how terrestrial carbon is stored and exchanged with the atmosphere across a variety of spatial and temporal scales. Improving TBM skills, and quantifying and reducing their estimation uncertainties, pose significant challenges. The Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP) is a formal multi-scale and multi-model intercomparison effort set up to tackle these challenges. The MsTMIP protocol prescribes standardized environmental driver data that are shared among model teams to facilitate model–model and model–observation comparisons. This paper describes …

A Bayesian Beta Kernel Model For Binary Classification And Online Learning Problems, Cameron A. Mackenzie, Theodore B. Trafalis, Kash Barker

Cameron A. MacKenzie

Recent advances in data mining have integrated kernel functions with Bayesian probabilistic analysis of Gaussian distributions. These machine-learning approaches can incorporate prior information with new data to calculate probabilistic rather than deterministic values for unknown parameters. This article extensively analyzes a specific Bayesian kernel model that uses a kernel function to calculate a posterior beta distribution that is conjugate to the prior beta distribution. Numerical testing of the beta kernel model on several benchmark datasets reveals that this model's accuracy is comparable with those of the support vector machine (SVM), relevance vector machine, naive Bayes, and logistic regression, and the …

Differential Effects Of Canopy Trimming And Litter Deposition On Litterfall And Nutrient Dynamics In A Wet Subtropical Forest, Steven J. Hall, Whendee L. Silver, Grizelle González

Steven J. Hall

Humid tropical forests have the highest rates of litterfall production globally, which fuels rapid nutrient recycling and high net ecosystem production. Severe storm events significantly alter patterns in litterfall mass and nutrient dynamics through a combination of canopy disturbance and litter deposition. In this study, we used a large-scale long-term manipulation experiment to explore the separate and combined effects of canopy trimming and litter deposition on litterfall rates and litter nutrient concentrations and content. The deposition of fine litter associated with the treatments was equivalent to more than two times the annual fine litterfall mass and nutrient content in control …

Complex Spatiotemporal Responses Of Global Terrestrial Primary Production To Climate Change And Increasing Atmospheric Co2 In The 21st Century, Shufen Pan, Hanqin Tian, Shree R. S. Dangal, Chi Zhang, Jia Yang, Bo Tao, Zhiyun Ouyang, Xiaoke Wang, Chaoqun (Crystal) Lu, Wei Ren, Kamaljit Banger, Qichun Yang, Bowen Zhang, Xia Li

Chaoqun (Crystal) Lu

Quantitative information on the response of global terrestrial net primary production (NPP) to climate change and increasing atmospheric CO2 is essential for climate change adaptation and mitigation in the 21st century. Using a process-based ecosystem model (the Dynamic Land Ecosystem Model, DLEM), we quantified the magnitude and spatiotemporal variations of contemporary (2000s) global NPP, and projected its potential responses to climate and CO2 changes in the 21st century under the Special Report on Emission Scenarios (SRES) A2 and B1 of Intergovernmental Panel on Climate Change (IPCC). We estimated a global terrestrial NPP of 54.6 (52.8–56.4) PgC yr−1 as a result …

A New Fuzzy Logic Approach To Capacitated Dynamic Dial-A-Ride Problem, Maher Maalouf, Cameron A. Mackenzie, Sridhar Radakrishnan, Mary Court

Cameron A. MacKenzie

Almost all Dial-a-Ride problems (DARP) described in the literature pertain to the design of optimal routes and schedules for n customers who specify pick-up and drop-off times. In this article we assume that the customer is mainly concerned with the drop-off time because it is the most important to the customer. Based on the drop-off time specified by the customer and the customer's location, a pick-up time is calculated and given to the customer by the dispatching office. We base our formulation on a dynamic fuzzy logic approach in which a new request is assigned to a vehicle. The fuzzy …

Wheeler, Andrea (2014) “The Sustainable School: Effective And Energy Efficient Ventilation In The Classroom, And The Question Of Educational Performance And Wellbeing” World Sustainable Building Conference, 28th – 30th October, Barcelona., Andrea S. Wheeler

Andrea S. Wheeler

Abstract: Within the context of designing a sustainable school, technical studies that address questions of air quality, educational performance and wellbeing challenge the trend toward providing for natural ventilation. This paper critically examines research literature that suggests that temperature and air quality are, in a large proportion of classrooms, so poor as to have a negative effect on children’s health and educational performance. Evidence in support of mechanical systems that control air quality contradicts a recent increase in natural ventilation, proposed as a means to conserve energy consumption in schools. Indoor Air Quality (IAQ) is generally not stressed, or indeed …

Breaking The Enzymatic Latch: Impacts Of Reducing Conditions On Hydrolytic Enzyme Activity In Tropical Forest Soils, Steven J. Hall, Jonathan Treffkorn, Whendee L. Silver

Steven J. Hall

The enzymatic latch hypothesis proposes that oxygen (O2) limitation promotes wetland carbon (C) storage by indirectly decreasing the activities of hydrolytic enzymes that decompose organic matter. Humid tropical forest soils are often characterized by low and fluctuating redox conditions and harbor a large pool of organic matter, yet they also have the fastest decomposition rates globally. We tested the enzymatic latch hypothesis across a soil O2 gradient in the Luquillo Experimental Forest, Puerto Rico, USA. Enzyme activities expressed on a soil mass basis did not systematically decline across a landscape O2 gradient, nor did phenolics accumulate, the proposed mechanism of …

The Historical Role Of Base Maps In Soil Geography, Bradley A. Miller, R. J. Schaetzl

Bradley A Miller

Soil mapping is a major goal of soil science. Soil maps rely upon accurate base maps, both for positional reference and to provide environmental data that can assist in the prediction of soil properties. This paper reviews the historical development of base maps used for soil mapping, and evaluates the dependence of soil mapping on base maps. The availability of geographic technology for producing base maps has both constrained and directed the geographic study of soil. The lack of accurate methods for determining location limited early geographic descriptions of soils to narratives, or to listings of attributes for property-based map …

Outage Constrained Robust Secure Transmission For Miso Wiretap Channels, Shuai Ma, Mingyi Hong, Engin Song, Xiangfeng Wang, Dechun Sun

Mingyi Hong

In this paper, we consider the robust secure beam-former design for multiple-input-single-output wiretap channels. Assuming that the eavesdroppers' channels are only partially available at the transmitter, we seek to maximize the secrecy rate under the transmit power and the secrecy rate outage probability constraint. The outage probability constraint requires that the secrecy rate exceed certain thresholds with high probability. Therefore, including such constraint in the design naturally ensures the desired robustness. Unfortunately, the presence of the probabilistic constraints makes the problem nonconvex and, hence, difficult to solve. In this paper, we investigate the outage probability constrained secrecy rate maximization problem …

The Effects Of Research & Development Funding On Scientific Productivity: Academic Chemistry, 1990-2009, Joshua L. Rosenbloom, Donna K. Ginther, Ted Juhl, Joseph Heppert

Joshua L. Rosenbloom

This article examines the relationship between Research & Development (R&D) funding and the production of knowledge by academic chemists. Using articles published, either raw counts or adjusted for quality, we find a strong, positive causal effect of funding on knowledge production. This effect is similar across subsets of universities, suggesting a relatively efficient allocation of R&D funds. Finally, we document a rapid acceleration in the rate at which chemical knowledge was produced in the late 1990s and early 2000s relative to the financial and human resources devoted to its production.

From Common Ground To Breaking New Ground: Founding Teams' Prior Shared Experience And Start-Up Performance, Florence E. Honore

Florence E. Honore

Start-ups founded by team members with prior shared experience in incumbent firms tend to perform better than other start-ups. While the prior shared experience brings relevant knowledge and coherent routines, the knowledge is also by definition redundant and can corner the new firms in local search and limit innovation. I propose that start-ups may mitigate the negative aspects of shared prior experience by including in the founding team individuals with extensive experience in multiple prior jobs or industries – i.e., job hoppers. I find that job hoppers positively moderate the effect of shared experience on performance. I also find that …

Evaluation Of A Health Education Program About Traumatic Brain Injury, Jane Mertz Garcia, Debra M. Sellers, Amy E. Hilgendorf, Debra L. Burnett

Debra M. Sellers

Objective: Our aim was to evaluate a health education programme (TBIoptions: Promoting Knowledge) designed to increase public awareness and understanding about traumatic brain injury (TBI) through in-person (classroom) and computer-based (electronic) learning environments. Design: We used a pre-post survey design with randomization of participants to classroom (N = 22) or electronic (N = 22) delivery of the programme, in classroom and computer laboratory settings on the campus of Kansas State University, Manhattan, KS. Method: Forty-four participants rated areas of knowledge about TBI prior to and after the programme experience. They also rated health programme quality and instructional strategies (e.g. video …

The Plasmodium Bottleneck: Malaria Parasite Losses In The Mosquito Vector, Ryan C. Smith, Joel Vega-Rodríguez, Marcelo Jacobs-Lorena

Ryan C. Smith

Nearly one million people are killed every year by the malaria parasite Plasmodium. Although the disease-causing forms of the parasite exist only in the human blood, mosquitoes of the genus Anopheles are the obligate vector for transmission. Here, we review the parasite life cycle in the vector and highlight the human and mosquito contributions that limit malaria parasite development in the mosquito host. We address parasite killing in its mosquito host and bottlenecks in parasite numbers that might guide intervention strategies to prevent transmission.

Immunization Against A Merozoite Sheddase Promotes Multiple Invasion Of Red Blood Cells And Attenuates Plasmodium Infection In Mice, Ryan C. Smith, Daisy D. Colón-López, Jürgen Bosch

Ryan C. Smith

Subtilisin-like protease 2 (SUB2) is a conserved serine protease utilized by Plasmodium parasites as a surface sheddase required for successful merozoite invasion of host red blood cells and has been implicated in ookinete invasion of the mosquito midgut. To determine if SUB2 is a suitable vaccine target to interfere with malaria parasite development, the effects of SUB2-immunization on the Plasmodium life cycle were examined in its vertebrate and invertebrate hosts. Swiss Webster mice were immunized with SUB2 peptides conjugated to Keyhole limpet hemocyanin (KLH) or KLH alone, and then challenged with Plasmodium berghei. To determine the effects of immunization on …

Base Station Activation And Linear Transceiver Design For Optimal Resource Management In Heterogeneous Networks, Wei-Cheng Liao, Mingyi Hong, Ya-Feng Liu, Zhi-Quan Luo

Mingyi Hong

In a densely deployed heterogeneous network (HetNet), the number of pico/micro base stations (BS) can be comparable with the number of the users. To reduce the operational overhead of the HetNet, proper identification of the set of serving BSs becomes an important design issue. In this work, we show that by jointly optimizing the transceivers and determining the active set of BSs, high system resource utilization can be achieved with only a small number of BSs. In particular, we provide formulations and efficient algorithms for such joint optimization problem, under the following two common design criteria: i) minimization of the …

These Are Not The K-Mers You Are Looking For: Efficient Online K-Mer Counting Using A Probabilistic Data Structure, Qingpeng Zhang, Jason Pell, Rosangela Canino-Koning, Adina Chuang Howe, C. Titus Brown

Adina Howe

K-mer abundance analysis is widely used for many purposes in nucleotide sequence analysis, including data preprocessing for de novo assembly, repeat detection, and sequencing coverage estimation. We present the khmer software package for fast and memory efficient online counting of k-mers in sequencing data sets. Unlike previous methods based on data structures such as hash tables, suffix arrays, and trie structures, khmer relies entirely on a simple probabilistic data structure, a Count-Min Sketch. The Count-Min Sketch permits online updating and retrieval of k-mer counts in memory which is necessary to support online k-mer analysis algorithms. On sparse data sets this …

Evaluation Of Trophic Niche Overlap Between Native Fishes And Young-Of-The-Year Common Carp, Michael J. Weber, Jessica M. Howell, Michael L. Rown

Michael J Weber Dr

Common carp Cyprinus carpio is a ubiquitous invasive species that commonly imposes negative effects on aquatic ecosystems. However, research evaluating the effects of carp on native fishes is limited. Carp are highly fecund and larvae and juveniles can be abundant. If age-0 carp use similar prey resources as native fishes, they may compete if food becomes limited. We used traditional diet analysis for samples during Jul. and Aug. 2008 in Brant Lake. Stable sotopes were used for samples collected during Aug. and Sep. 2009 in Brant Lake and Lake Sinai to examine prey resource use by age-0 carp and four …

Intraocular Pressure Changes In Equine Athletes During Endurance Competitions, Rachel A. Allbaugh, Susan M. Keil, Zhining Ou, Nora M. Bello

Rachel A. Allbaugh

Objective To assess intraocular pressure (IOP) in conditioned equine athletes and document changes with exercise. A secondary objective was to assess associations between IOP and heart rate, as well as with other subjective physical parameters.

Sample Population Horses were evaluated during 50 mile endurance ride competitions. Data were collected on 69 horses during 5 different competitions at 3 different locations with 59 horses ridden once, 9 horses ridden in two competitions, and 1 horse ridden in three competitions for a total of 80 horse-ride combinations.

Procedures Intraocular pressure was measured using a TonoVet® tonometer in both eyes of each horse …

Impact Of Large-Scale Climate Extremes On Biospheric Carbon Fluxes: An Intercomparison Based On Mstmip Data, Jakov Zscheischler, Anna M. Michalak, Christopher Schwalm, Miguel D. Mahecha, Deborah N. Huntzinger, Markus Reichstein, Gwenaëlle Berthier, Philippe Ciais, Robert B. Cook, Bassil El-Masri, Maoyi Huang, Akihiko Ito, Atul Jain, Anthony King, Huimin Lei, Chaoqun (Crystal) Lu, Jiafu Mao, Shushi Peng, Benjamin Poulter, Daniel Ricciuto, Xiaoying Shi, Bo Tao, Hanqin Tian, Nicolas Viovy, Weile Wang, Yaxing Wei, Jia Yang, Ning Zeng

Chaoqun (Crystal) Lu

Understanding the role of climate extremes and their impact on the carbon (C) cycle is increasingly a focus of Earth system science. Climate extremes such as droughts, heat waves, or heavy precipitation events can cause substantial changes in terrestrial C fluxes. On the other hand, extreme changes in C fluxes are often, but not always, driven by extreme climate conditions. Here we present an analysis of how extremes in temperature and precipitation, and extreme changes in terrestrial C fluxes are related to each other in 10 state-of-the-art terrestrial carbon models, all driven by the same climate forcing. We use model …

Influence Of Environment On The Measurement Of Rates Of Charge Transport Across Agts/Sam//Ga2o3/Egain Junctions, Jabulani R. Barber, Hyo Jae Yoon, Carleen M. Bowers, Martin M. Thuo, Benjamin Breiten, Diana M. Gooding, George M. Whitesides

Martin M. Thuo

This paper investigates the influence of the atmosphere used in the fabrication of top electrodes from the liquid eutectic of gallium and indium (EGaIn) (the so-called “EGaIn” electrodes), and in measurements of current density, J(V) (A/cm2), across self-assembled monolayers (SAMs) incorporated into Ag/SR//Ga2O3/EGaIn junctions, on values of J(V) obtained using these electrodes. A gas-tight measurement chamber was used to control the atmosphere in which the electrodes were formed, and also to control the environment in which the electrodes were used to measure current densities across SAM-based junctions. Seven different atmospheres—air, oxygen, nitrogen, argon, and ammonia, as well as air containing …

Fabrication Of Low-Cost Paper-Based Microfluidic Devices By Embossing Or Cut-And-Stack Methods, Martin M. Thuo, Ramses V. Martinez, Wen-Jie Lan, Xinyu Liu, Jabulani Barber, Manza B. Atkinson, Dineth Bandarage, Jean-Francis Bloch, George M. Whitesides

Martin M. Thuo

This article describes the use of embossing and “cut-and-stack” methods of assembly, to generate microfluidic devices from omniphobic paper and demonstrates that fluid flowing through these devices behaves similarly to fluid in an open-channel microfluidic device. The porosity of the paper to gases allows processes not possible in devices made using PDMS or other nonporous materials. Droplet generators and phase separators, for example, could be made by embossing “T”-shaped channels on paper. Vertical stacking of embossed or cut layers of omniphobic paper generated three-dimensional systems of microchannels. The gas permeability of the paper allowed fluid in the microchannel to contact …

Min Flow Rate Maximization For Software Defined Radio Access Networks, Wei-Cheng Liao, Mingyi Hong, Hamid Farmanbar, Xu Li, Zhi-Quan Luo, Hang Zhang

Mingyi Hong

We consider a cloud-based heterogeneous network of base stations (BSs) connected via a backhaul network of routers and wired/wireless links with limited capacity. The optimal provision of such networks requires proper resource allocation across the radio access links in conjunction with appropriate traffic engineering within the backhaul network. In this paper, we propose an efficient algorithm for joint resource allocation across the wireless links and flow control over the entire network. The proposed algorithm, which maximizes the min-rate among all the transmitted commodities, is based on a decomposition approach that leverages both the alternating direction method of multipliers (ADMM) and …

Cardiorespiratory Fitness Reduces The Risk Of Incident Hypertension Associated With A Parental History Of Hypertension., Robin Shook, D. C. Lee, X. Sui, V. Prasad, S. P. Hooker, T. S. Church, S. N. Blair

Robin Shook

Family history of hypertension increases the risk of an individual to develop hypertension, whereas moderate-to-high cardiorespiratory fitness has the opposite effect. However, the joint association of each on the development of hypertension is not well understood. We studied fitness and incident hypertension in 6278 participants who were given a preventative medical examination. Thirty-three percent reported a parent with hypertension, and there were 1545 cases of incident hypertension after a mean of 4.7 years. The presence of parental hypertension was associated with a 28% higher risk of developing hypertension after adjustments for age, sex, and examination year. After further adjustments for …

The Independent Association Between Diet Quality And Body Composition, Clemens Drenowatz, Robin Shook, Gregory A. Hand, James R. Hebert, Steven N. Blair

Robin Shook

Excess body weight is associated with an imbalance between energy expenditure and dietary intake but evidence on the association between diet quality and body composition remains equivocal. Rather than relying on differences in diet quality between overweight/obese and normal weight adults, this study examined the association between the Healthy Eating Index 2010 (HEI-2010) and body fatness on a continuous scale, independent of physical activity (PA). Further the association between components of the HEI-2010 and risk for overweight/obesity was explored. 407 adults (27.6 6 3.7 years) provided at least two 24-hour diet recalls over a period of 14 days, which were …

Moderate Cardiorespiratory Fitness Is Positively Associated With Resting Metabolic Rate In Young Adults., Robin Shook, G. A. Hand, A. E. Paluch, X. Wang, R. Moran, J. R. Hebert, C. J. Lavie, S. N. Blair

Robin Shook

OBJECTIVE: To determine whether moderate cardiorespiratory fitness (CRF) or moderate to vigorous physical activity (MVPA) is associated with elevations in resting metabolic rate (RMR) similar to findings previously observed in endurance athletes. PARTICIPANTS AND METHODS: Using a cross-sectional design, we measured CRF, RMR, body composition, energy expenditure, and time in MVPA via an arm-based activity monitor in 423 young adults (mean age, 27.6 years). Based on the results of a fitness test, participants were classified into CRF tertiles (low, moderate, or high) by sex. RESULTS: There were significant differences among the low-, moderate-, and high-CRF groups for mean ± SD …

Climate And Land Use Controls On Soil Organic Carbon In The Loess Plateau Region Of China, Yaai Dang, Wei Ren, Bo Tao, Guangsheng Chen, Chaoqun (Crystal) Lu, Jia Yang, Shufen Pan, Guodong Wang, Shiqing Li, Hanqin Tian

Chaoqun (Crystal) Lu

The Loess Plateau of China has the highest soil erosion rate in the world where billion tons of soil is annually washed into Yellow River. In recent decades this region has experienced significant climate change and policy-driven land conversion. However, it has not yet been well investigated how these changes in climate and land use have affected soil organic carbon (SOC) storage on the Loess Plateau. By using the Dynamic Land Ecosystem Model (DLEM), we quantified the effects of climate and land use on SOC storage on the Loess Plateau in the context of multiple environmental factors during the period …

Revealing The Bacterial Butyrate Synthesis Pathways By Analyzing (Meta)Genomic Data, Marius Vital, Adina Chuang Howe, James M. Tiedje

Adina Howe

Butyrate-producing bacteria have recently gained attention, since they are important for a healthy colon and when altered contribute to emerging diseases, such as ulcerative colitis and type II diabetes. This guild is polyphyletic and cannot be accurately detected by 16S rRNA gene sequencing. Consequently, approaches targeting the terminal genes of the main butyrate-producing pathway have been developed. However, since additional pathways exist and alternative, newly recognized enzymes catalyzing the terminal reaction have been described, previous investigations are often incomplete. We undertook a broad analysis of butyrate-producing pathways and individual genes by screening 3,184 sequenced bacterial genomes from the Integrated Microbial …

Tuning The Selectivity Of Ionic Liquid Stationary Phases For Enhanced Separation Of Nonpolar Analytes In Kerosene Using Multidimensional Gas Chromatography, Leandro W. Hantao, Ali Najafi, Cheng Zhang, Fabio Augusto, Jared L. Anderson

Jared L. Anderson

In this study, a series of ionic liquids (ILs) are evaluated as stationary phases in comprehensive two-dimensional gas chromatography (GC × GC) for the separation of aliphatic hydrocarbons from kerosene. IL-based stationary phases were carefully designed to evaluate the role of cavity formation/dispersive interaction on the chromatographic retention of nonpolar analytes by GC × GC. The maximum allowable operating temperature (MAOT) of the IL-based columns was compared to that of commercial IL-based columns. Evaluation of the solvation characteristics of GC columns guided the selection of the best performing IL-based stationary phases for the resolution of aliphatic hydrocarbons, namely, trihexyl(tetradecyl)phosphonium tetrachloroferrate …

Top 10 Research Questions Related To Energy Balance, Robin P. Shook, Gregory A. Hand, Steven N. Blair

Robin Shook

Obesity is the result of a mismatch between the amount of calories consumed and the amount of calories expended during an extended period of time. This relationship is described by the energy balance equation, which states the rate of change in energy storage depots in the body are equal to the rate of energy intake minus the rate of energy expenditure. Although this relationship may appear easy to understand based on simple mathematics, in reality, a variety of known and unknown systems influence the components of energy balance (energy storage, energy intake, energy expenditure). Clearly, if a complete understanding of …

Low Fitness Partially Explains Resting Metabolic Rate Differences Between African American And White Women., Robin Shook, G. A. Hand, X. Wang, A. E. Paluch, R. Moran, J. R. Hebert, D. L. Swift, C. J. Lavie, S. N. Blair

Robin Shook

BACKGROUND: High levels of obesity among African American women have been hypothesized to be partially resultant from a lower resting metabolic rate compared with white women. The aim of the current study was to determine if differences in cardiorespiratory fitness and moderate-to-vigorous physical activity are associated with differences in resting metabolic rate among free-living young adult African American women and white women. METHODS: Participants were 179 women (white women n = 141, African American women n = 38, mean age = 27.7 years). Resting metabolic rate was measured using indirect calorimetry, body composition using dual energy x-ray absorptiometry, cardiorespiratory fitness …