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Student Outcomes From Participating In An International Stem Service-Learning Course, Kristy L. Daniel, Chandrani Mishra Mar 2017

Student Outcomes From Participating In An International Stem Service-Learning Course, Kristy L. Daniel, Chandrani Mishra

Faculty Publications

The purpose of this study was to measure student affective, behavior, and content (ABC) and global awareness outcomes after participating in a science, technology, engineering, and mathematics (STEM)-based international service-learning (ISL) course and impacts on long-term retention in STEM fields. We compared experiences from 12 participants (undergraduate and graduate students) enrolled in a STEM-based ISL course with experiences from four students enrolled in the same course without the service-learning component. The ISL course involved classroom discussions on environmental topics and four local and ISL projects with community partners to contribute to conservation efforts. Data came from student responses on a …


Reliability Of Pulse Waveform Separation Analysis: Effects Of Posture And Fasting, Lee Stoner, Daniel Credeur, Simon Fryer, James Faulkner, Danielle Lambrick, Bathany Barone Gibbs Mar 2017

Reliability Of Pulse Waveform Separation Analysis: Effects Of Posture And Fasting, Lee Stoner, Daniel Credeur, Simon Fryer, James Faulkner, Danielle Lambrick, Bathany Barone Gibbs

Faculty Publications

Objective: Oscillometric pulse wave analysis devices enable, with relative simplicity and objectivity, the measurement of central hemodynamic parameters. The important parameters are central blood pressures and indices of arterial wave reflection, including wave separation analysis (backward pressure component Pb and reflection magnitude). This study sought to determine whether the measurement precision (between-day reliability) of Pb and reflection magnitude: exceeds the criterion for acceptable reliability; and is affected by posture (supine, seated) and fasting state.

Methods: Twenty healthy adults (50% female, 27.9 years, 24.2 kg/m2) were tested on six different mornings: 3 days fasted, 3 …


Search Strategy Development In A Flipped Library Classroom: A Student-Focused Assessment, Michael C. Goates, Gregory M. Nelson, Megan Frost Mar 2017

Search Strategy Development In A Flipped Library Classroom: A Student-Focused Assessment, Michael C. Goates, Gregory M. Nelson, Megan Frost

Faculty Publications

Librarians at Brigham Young University compared search statement development between traditional lecture and flipped instruction sessions. Students in lecture sessions scored significantly higher on developing search statements than those in flipped sessions. However, student evaluations show a strong preference for pedagogies that incorporate elements from both lecture and flipped methodologies. Reasons for lower flipped-session scores may include a lack of student accountability, strong preference for a live demonstration, and disconnections between online tutorial content and in-class collaborative activities. Librarians using a flipped classroom should consider ways to help students make meaningful connections between online tutorials and in-class activities.


Data-Driven Identification Of Potential Zika Virus Vectors, Michelle V. Evans, Tad A. Dallas, Barbara A. Han, Courtney C. Murdock, John M. Drake Feb 2017

Data-Driven Identification Of Potential Zika Virus Vectors, Michelle V. Evans, Tad A. Dallas, Barbara A. Han, Courtney C. Murdock, John M. Drake

Faculty Publications

© Evans et al. Zika is an emerging virus whose rapid spread is of great public health concern. Knowledge about transmission remains incomplete, especially concerning potential transmission in geographic areas in which it has not yet been introduced. To identify unknown vectors of Zika, we developed a data-driven model linking vector species and the Zika virus via vector-virus trait combinations that confer a propensity toward associations in an ecological network connecting flaviviruses and their mosquito vectors. Our model predicts that thirty-five species may be able to transmit the virus, seven of which are found in the continental United States, including …


Analysis Of Co-Associated Transcription Factors Via Ordered Adjacency Differences On Motif Distribution, Gaofeng Pan, Jijun Tang, Fei Guo Feb 2017

Analysis Of Co-Associated Transcription Factors Via Ordered Adjacency Differences On Motif Distribution, Gaofeng Pan, Jijun Tang, Fei Guo

Faculty Publications

Transcription factors (TFs) binding to specific DNA sequences or motifs, are elementary to the regulation of transcription. The gene is regulated by a combination of TFs in close proximity. Analysis of co-TFs is an important problem in understanding the mechanism of transcriptional regulation. Recently, ChIP-seq in mapping TF provides a large amount of experimental data to analyze co-TFs. Several studies show that if two TFs are co-associated, the relative distance between TFs exhibits a peak-like distribution. In order to analyze co-TFs, we develop a novel method to evaluate the associated situation between TFs. We design an adjacency score based on …


Binding Of Nitric Oxide In Cdgsh-Type [2fe-2s] Clusters Of The Human Mitochondrial Protein Miner2, Zishuo Cheng, Aaron P. Landry, Yiming Wang, Huangen Ding Feb 2017

Binding Of Nitric Oxide In Cdgsh-Type [2fe-2s] Clusters Of The Human Mitochondrial Protein Miner2, Zishuo Cheng, Aaron P. Landry, Yiming Wang, Huangen Ding

Faculty Publications

© 2017 by The American Society for Biochemistry and Molecular Biology, Inc. Iron-sulfur proteins are among the primary targets of nitric oxide in cells. Previous studies have shown that iron-sulfur clusters hosted by cysteine residues in proteins are readily disrupted by nitric oxide forming a protein-bound dinitrosyl iron complex, thiolate-bridged di-iron tetranitrosyl complex, or octanitrosyl cluster. Here we report that human mitochondrial protein Miner2 [2Fe-2S] clusters can bind nitric oxide without disruption of the clusters. Miner2 is a member of a new CDGSH ironsulfur protein family that also includes two mitochondrial proteins: the type II diabetes-related mitoNEET and the Wolfram …


Volcanic Soils As Sources Of Novel Co-Oxidizing Paraburkholderia And Burkholderia: Paraburkholderia Hiiakae Sp. Nov., Paraburkholderia Metrosideri Sp. Nov., Paraburkholderia Paradisi Sp. Nov., Paraburkholderia Peleae Sp. Nov., And Burkholderia Alpina Sp. Nov. A Member Of The Burkholderia Cepacia Complex, Carolyn F. Weber, Gary M. King Feb 2017

Volcanic Soils As Sources Of Novel Co-Oxidizing Paraburkholderia And Burkholderia: Paraburkholderia Hiiakae Sp. Nov., Paraburkholderia Metrosideri Sp. Nov., Paraburkholderia Paradisi Sp. Nov., Paraburkholderia Peleae Sp. Nov., And Burkholderia Alpina Sp. Nov. A Member Of The Burkholderia Cepacia Complex, Carolyn F. Weber, Gary M. King

Faculty Publications

© 2017 Weber and King. Previous studies showed that members of the Burkholderiales were important in the succession of aerobic, molybdenum-dependent CO oxidizing-bacteria on volcanic soils. During these studies, four isolates were obtained from Kilauea Volcano (Hawai'i, USA); one strain was isolated from Pico de Orizaba (Mexico) during a separate study. Based on 16S rRNA gene sequence similarities, the Pico de Orizaba isolate and the isolates from Kilauea Volcano were provisionally assigned to the genera Burkholderia and Paraburkholderia, respectively. Each of the isolates possessed a form I coxL gene that encoded the catalytic subunit of carbon monoxide dehydrogenase (CODH); none …


Bacterioferritin: Structure, Dynamics, And Protein-Protein Interactions At Play In Iron Storage And Mobilization, Mario Rivera Feb 2017

Bacterioferritin: Structure, Dynamics, And Protein-Protein Interactions At Play In Iron Storage And Mobilization, Mario Rivera

Faculty Publications

© 2017 American Chemical Society. Conspectus Despite its essentiality to life, iron presents significant challenges to cells: the exceedingly low solubility of Fe3+ limits its bioavailability, and the reactivity of Fe2+ toward H2O2 is a source of the toxic hydroxyl radical (HO•). Consequently, cellular levels of free iron are highly regulated to ensure sufficiency while preventing iron-induced toxicity. Relatively little is known about the fate of iron in the bacterial cytosol or how cells balance the need for relatively high cytosolic iron concentrations with the potential toxicity of the nutrient. Iron storage proteins are integral to iron metabolism, and bacteria …


Inhibition Of Cdk8 Mediator Kinase Suppresses Estrogen Dependent Transcription And The Growth Of Estrogen Receptor Positive Breast Cancer, Martina S. Mcdermott, Alexander A. Chumanevich, Chang-Uk Lim, Jiaxin Liang, Mengqian Chen, Serena Altilia, David Oliver, James M. Rae, Michael Shtutman, Hippokratis Kiaris, Balázs Győrffy, Igor Roninson, Eugenia Broude Feb 2017

Inhibition Of Cdk8 Mediator Kinase Suppresses Estrogen Dependent Transcription And The Growth Of Estrogen Receptor Positive Breast Cancer, Martina S. Mcdermott, Alexander A. Chumanevich, Chang-Uk Lim, Jiaxin Liang, Mengqian Chen, Serena Altilia, David Oliver, James M. Rae, Michael Shtutman, Hippokratis Kiaris, Balázs Győrffy, Igor Roninson, Eugenia Broude

Faculty Publications

Hormone therapy targeting estrogen receptor (ER) is the principal treatment for ER-positive breast cancers. However, many cancers develop resistance to hormone therapy while retaining ER expression. Identifying new druggable mediators of ER function can help to increase the efficacy of ER-targeting drugs. Cyclin-dependent kinase 8 (CDK8) is a Mediator complex-associated transcriptional regulator with oncogenic activities. Expression of CDK8, its paralog CDK19 and their binding partner Cyclin C are negative prognostic markers in breast cancer. Meta-analysis of transcriptome databases revealed an inverse correlation between CDK8 and ERα expression, suggesting that CDK8 could be functionally associated with ER. We have found that …


First Evidence Of Denitrification Vis-À-Vis Monsoon In The Arabian Sea Since Late Miocene, Shubham Tripathi, Manish Tiwari, Jongmin Lee, Boo Keun Khim Feb 2017

First Evidence Of Denitrification Vis-À-Vis Monsoon In The Arabian Sea Since Late Miocene, Shubham Tripathi, Manish Tiwari, Jongmin Lee, Boo Keun Khim

Faculty Publications

© The Author(s) 2017. In the Arabian Sea, South Asian monsoon (SAM)-induced high surface water productivity coupled with poor ventilation of intermediate water results in strong denitrification within the oxygen minimum zone (OMZ). Despite the significance of denitrification in the Arabian Sea, we have no long-term record of its evolution spanning the past several million years. Here, we present the first record of denitrification evolution since Late Miocene (∼10.2 Ma) in the Eastern Arabian Sea, where the SAM generates moderate surface water productivity, based on the samples retrieved during the International Ocean Discovery Program (IODP) Expedition 355. We find that …


The Molecular Basis For The Lack Of Inflammatory Responses In Mouse Embryonic Stem Cells And Their Differentiated Cells, William D'Angelo, Chandan Gurung, Dhiraj Acharya, Natalya Ortolano, Fengwei Bai, Yan-Lin Guo Feb 2017

The Molecular Basis For The Lack Of Inflammatory Responses In Mouse Embryonic Stem Cells And Their Differentiated Cells, William D'Angelo, Chandan Gurung, Dhiraj Acharya, Natalya Ortolano, Fengwei Bai, Yan-Lin Guo

Faculty Publications

We reported previously that mouse embryonic stem cells do not have a functional IFN-based antiviral mechanism. The current study extends our investigation to the inflammatory response in mouse embryonic stem cells and mouse embryonic stem cell–differentiated cells. We demonstrate that LPS, TNF-α, and viral infection, all of which induce robust inflammatory responses in naturally differentiated cells, failed to activate NF-κB, the key transcription factor that mediates inflammatory responses, and were unable to induce the expression of inflammatory genes in mouse embryonic stem cells. Similar results were obtained in human embryonic stem cells. In addition to the inactive state of NF-κB, …


Fewer Acute Respiratory Infection Episodes Among Patients Receiving Treatment For Gastroesophageal Reflux Disease, Herng-Ching Lin, Sudha Xirasagar, Shiu-Dong Chung, Chung-Chien Huang, Ming- Chieh Tsai, Chao-Hung Chen Feb 2017

Fewer Acute Respiratory Infection Episodes Among Patients Receiving Treatment For Gastroesophageal Reflux Disease, Herng-Ching Lin, Sudha Xirasagar, Shiu-Dong Chung, Chung-Chien Huang, Ming- Chieh Tsai, Chao-Hung Chen

Faculty Publications

Patients with gastroesophageal reflux disease (GERD) present with comorbid complications with implications for healthcare utilization. To date, little is known about the effects of GERD treatment with a proton-pump inhibitor (PPI) on patients’ subsequent healthcare utilization for acute respiratory infections (ARIs). This population-based study compared ARI episodes captured through outpatient visits, one year before and one year after GERD patients received PPI treatment. We used retrospective data from the Longitudinal Health Insurance Database 2005 in Taiwan, comparing 21,486 patients diagnosed with GERD from 2010 to 2012 with 21,486 age-sex matched comparison patients without GERD. Annual ARI episodes represented by ambulatory …


Electrophysiological Endophenotypes And The Error-Related Negativity (Ern) In Autism Spectrum Disorder: A Family Study, Scott A. Baldwin, Ann Clawson, Mikle South, Michael J. Larson Feb 2017

Electrophysiological Endophenotypes And The Error-Related Negativity (Ern) In Autism Spectrum Disorder: A Family Study, Scott A. Baldwin, Ann Clawson, Mikle South, Michael J. Larson

Faculty Publications

We examined the error-related negativity (ERN) as an endophenotype of ASD by comparing the ERN in families of ASD probands to control families. We hypothesized that ASD probands and families would display reduced-amplitude ERN relative to controls. Participants included 148 individuals within 39 families consisting of a mother, father, sibling, and proband. Robust ANOVAs revealed non-significant differences in ERN amplitude and behavioral performance among ASD probands relative to control youth. In subsequent multiple regression analyses group and kinship (proband, sibling, mother, father) did not significantly predict ΔERN (error minus correct ERN) or behavioral performance. Results do not provide evidence for …


Small Grants Make A Big Difference, Susan Walsh Feb 2017

Small Grants Make A Big Difference, Susan Walsh

Faculty Publications

No abstract provided.


Aquaculture Genomics, Genetics And Breeding In The United States: Current Status, Challenges, And Priorities For Future Research, Hisham Abdelrahman, Mohamed Elhady, Acacia Alcivar-Warren, Standish Allen, Rafet Al-Tobasei, Lisui Bao, Ben Beck, Harvey Blackburn, Brian Bosworth, John Buchanan, Jesse Chappell, William Daniels, Sheng Dong, Rex Dunham, Evan Durland, Ahmed Elaswad, Marta Gomez-Chiarri, Kamal Gosh, Ximing Guo, Perry Hackett, Terry Hanson, Dennis Hedgecock, Tiffany Howard, Leigh Holland, Molly Jackson, Yulin Jin, Karim Kahlil, Thomas Kocher, Tim Leeds, Ning Li, Lauren Lindsey, Shikai Liu, Zhanjiang Liu Feb 2017

Aquaculture Genomics, Genetics And Breeding In The United States: Current Status, Challenges, And Priorities For Future Research, Hisham Abdelrahman, Mohamed Elhady, Acacia Alcivar-Warren, Standish Allen, Rafet Al-Tobasei, Lisui Bao, Ben Beck, Harvey Blackburn, Brian Bosworth, John Buchanan, Jesse Chappell, William Daniels, Sheng Dong, Rex Dunham, Evan Durland, Ahmed Elaswad, Marta Gomez-Chiarri, Kamal Gosh, Ximing Guo, Perry Hackett, Terry Hanson, Dennis Hedgecock, Tiffany Howard, Leigh Holland, Molly Jackson, Yulin Jin, Karim Kahlil, Thomas Kocher, Tim Leeds, Ning Li, Lauren Lindsey, Shikai Liu, Zhanjiang Liu

Faculty Publications

Advancing the production efficiency and profitability of aquaculture is dependent upon the ability to utilize a diverse array of genetic resources. The ultimate goals of aquaculture genomics, genetics and breeding research are to enhance aquaculture production efficiency, sustainability, product quality, and profitability in support of the commercial sector and for the benefit of consumers. In order to achieve these goals, it is important to understand the genomic structure and organization of aquaculture species, and their genomic and phenomic variations, as well as the genetic basis of traits and their interrelationships. In addition, it is also important to understand the mechanisms …


Localization Of Glutamatergic, Gabaergic, And Cholinergic Neurons In The Brain Of The African Cichlid Fish, Astatotilapia Burtoni, Karen P. Maruska, Julie M. Butler, Karen E. Field, Danielle T. Porter Feb 2017

Localization Of Glutamatergic, Gabaergic, And Cholinergic Neurons In The Brain Of The African Cichlid Fish, Astatotilapia Burtoni, Karen P. Maruska, Julie M. Butler, Karen E. Field, Danielle T. Porter

Faculty Publications

© 2016 Wiley Periodicals, Inc. Neural communication depends on release and reception of different neurotransmitters within complex circuits that ultimately mediate basic biological functions. We mapped the distribution of glutamatergic, GABAergic, and cholinergic neurons in the brain of the African cichlid fish Astatotilapia burtoni using in situ hybridization to label vesicular glutamate transporters (vglut1, vglut2.1, vglut3), glutamate decarboxylases (gad1, gad2), and choline acetyltransferase (chat). Cells expressing the glutamatergic markers vgluts 1–3 show primarily nonoverlapping distribution patterns, with the most widespread expression observed for vglut2.1, and more restricted expression of vglut1 and vglut3. vglut1 is prominent in granular layers of the …


The Secondary Resistome Of Multidrug-Resistant Klebsiella Pneumoniae, Bimal Jana, Amy K. Cain, William T. Doerrler, Christine J. Boinett, Maria C. Fookes, Julian Parkhill, Luca Guardabassi Feb 2017

The Secondary Resistome Of Multidrug-Resistant Klebsiella Pneumoniae, Bimal Jana, Amy K. Cain, William T. Doerrler, Christine J. Boinett, Maria C. Fookes, Julian Parkhill, Luca Guardabassi

Faculty Publications

© 2017 The Author(s). Klebsiella pneumoniae causes severe lung and bloodstream infections that are difficult to treat due to multidrug resistance. We hypothesized that antimicrobial resistance can be reversed by targeting chromosomal non-essential genes that are not responsible for acquired resistance but essential for resistant bacteria under therapeutic concentrations of antimicrobials. Conditional essentiality of individual genes to antimicrobial resistance was evaluated in an epidemic multidrug-resistant clone of K. pneumoniae (ST258). We constructed a high-density transposon mutant library of >430,000 unique Tn5 insertions and measured mutant depletion upon exposure to three clinically relevant antimicrobials (colistin, imipenem or ciprofloxacin) by Transposon Directed …


Rapid Transcriptional Plasticity Of Duplicated Gene Clusters Enables A Clonally Reproducing Aphid To Colonise Diverse Plant Species, Thomas C. Mathers, Yazhou Chen, Gemy Kaithakottil, Fabrice Legeai, Sam T. Mugford, Patrice Baa-Puyoulet, Anthony Bretaudeau, Bernardo Clavijo, Stefano Colella, Olivier Collin, Tamas Dalmay, Thomas Derrien, Honglin Feng, Toni Gabaldón, Anna Jordan, Irene Julca, Graeme J. Kettles, Krissana Kowitwanich, Dominique Lavenier, Paolo Lenzi, Sara Lopez-Gomollon, Damian Loska, Daniel Mapleson, Florian Maumus, Simon Moxon, Daniel R.G. Price, Akiko Sugio, Manuella Van Munster, Marilyne Uzest, Darren Waite, Georg Jander, Denis Tagu, Alex C.C. Wilson Feb 2017

Rapid Transcriptional Plasticity Of Duplicated Gene Clusters Enables A Clonally Reproducing Aphid To Colonise Diverse Plant Species, Thomas C. Mathers, Yazhou Chen, Gemy Kaithakottil, Fabrice Legeai, Sam T. Mugford, Patrice Baa-Puyoulet, Anthony Bretaudeau, Bernardo Clavijo, Stefano Colella, Olivier Collin, Tamas Dalmay, Thomas Derrien, Honglin Feng, Toni Gabaldón, Anna Jordan, Irene Julca, Graeme J. Kettles, Krissana Kowitwanich, Dominique Lavenier, Paolo Lenzi, Sara Lopez-Gomollon, Damian Loska, Daniel Mapleson, Florian Maumus, Simon Moxon, Daniel R.G. Price, Akiko Sugio, Manuella Van Munster, Marilyne Uzest, Darren Waite, Georg Jander, Denis Tagu, Alex C.C. Wilson

Faculty Publications

Background: The prevailing paradigm of host-parasite evolution is that arms races lead to increasing specialisation via genetic adaptation. Insect herbivores are no exception and the majority have evolved to colonise a small number of closely related host species. Remarkably, the green peach aphid, Myzus persicae, colonises plant species across 40 families and single M. persicae clonal lineages can colonise distantly related plants. This remarkable ability makes M. persicae a highly destructive pest of many important crop species. Results: To investigate the exceptional phenotypic plasticity of M. persicae, we sequenced the M. persicae genome and assessed how one clonal lineage responds …


Synthetic Aperture Radar (Sar)-Based Paddy Rice Monitoring System: Development And Application In Key Rice Producing Areas In Tropical Asia, T. D. Setiyono, F. Holecz, N. I. Khan, M. Barbieri, E. Quicho, F. Collivignarelli, A. Maunahan, L. Gatti, G. C. Romuga Feb 2017

Synthetic Aperture Radar (Sar)-Based Paddy Rice Monitoring System: Development And Application In Key Rice Producing Areas In Tropical Asia, T. D. Setiyono, F. Holecz, N. I. Khan, M. Barbieri, E. Quicho, F. Collivignarelli, A. Maunahan, L. Gatti, G. C. Romuga

Faculty Publications

Reliable and regular rice information is essential part of many countries' national accounting process but the existing system may not be sufficient to meet the information demand in the context of food security and policy. Synthetic Aperture Radar (SAR) imagery is highly suitable for detecting lowland paddy rice, especially in tropical region where pervasive cloud cover in the rainy seasons limits the use of optical imagery. This study uses multi-temporal X-band and C-band SAR imagery, automated image processing, rule-based classification and field observations to classify rice in multiple locations across Tropical Asia and assimilate the information into ORYZA Crop Growth …


Naturally-Occurring Changes In Social-Cognitive Factors Modify Change In Physical Activity During Early Adolescence, Rod K. Dishman, Marsha Dowda, Kerry L. Mciver, Ruth P. Saunders, Russell R. Pate Feb 2017

Naturally-Occurring Changes In Social-Cognitive Factors Modify Change In Physical Activity During Early Adolescence, Rod K. Dishman, Marsha Dowda, Kerry L. Mciver, Ruth P. Saunders, Russell R. Pate

Faculty Publications

Purpose

To determine whether naturally-occurring changes in children’s motives and beliefs are associated with the steep decline in physical activity observed from childhood to early adolescence.

Methods

Latent growth modeling was applied in longitudinal tests of social-cognitive influences, and their interactions, on physical activity in a large cohort of boys and girls evaluated annually between 5th and 7th grades.

Results

Measurement equivalence of motives and beliefs was confirmed between boys and girls. After adjustment for gender and maturity differences, physical activity declined less in children who reported the least decreases in self-efficacy for overcoming barriers to activity and perceived parental …


Neighborhood Environment And Falls Among Community-Dwelling Older Adults, Emily Joy Nicklett, Matthew C. Lohman Ph.D., Matthew Lee Smith Feb 2017

Neighborhood Environment And Falls Among Community-Dwelling Older Adults, Emily Joy Nicklett, Matthew C. Lohman Ph.D., Matthew Lee Smith

Faculty Publications

Background: Falls present a major challenge to active aging, but the relationship between neighborhood factors and falls is poorly understood. This study examined the relationship between fall events and neighborhood factors, including neighborhood social cohesion (sense of belonging, trust, friendliness, and helpfulness) and physical environment (vandalism/graffiti, rubbish, vacant/deserted houses, and perceived safety walking home at night). Methods: Data were analyzed from 9259 participants over four biennial waves (2006–2012) of the Health and Retirement Study (HRS), a nationally representative sample of adults aged 65 and older in the United States. Results: In models adjusting for demographic and health-related covariates, a one-unit …


Energetics Of The S2 State Spin Isomers Of The Oxygen-Evolving Complex Of Photosystem Ii, David J. Vinyard, Sahr Khan, Mikhail Askerka, Victor S. Batista, Gary W. Brudvig Feb 2017

Energetics Of The S2 State Spin Isomers Of The Oxygen-Evolving Complex Of Photosystem Ii, David J. Vinyard, Sahr Khan, Mikhail Askerka, Victor S. Batista, Gary W. Brudvig

Faculty Publications

© 2017 American Chemical Society. The S2 redox intermediate of the oxygen-evolving complex in photosystem II is present as two spin isomers. The S = 1/2 isomer gives rise to a multiline electron paramagnetic resonance (EPR) signal at g = 2.0, whereas the S = 5/2 isomer exhibits a broad EPR signal at g = 4.1. The electronic structures of these isomers are known, but their role in the catalytic cycle of water oxidation remains unclear. We show that formation of the S = 1/2 state from the S = 5/2 state is exergonic at temperatures above 160 K. However, …


In Situ Probing And Synthetic Control Of Cationic Ordering In Ni-Rich Layered Oxide Cathodes, Jianqing Zhao, Wei Zhang, Ashfia Huq, Scott T. Misture, Boliang Zhang, Shengmin Guo, Lijun Wu, Yimei Zhu, Zonghai Chen, Khalil Amine, Feng Pan, Jianming Bai, Feng Wang Feb 2017

In Situ Probing And Synthetic Control Of Cationic Ordering In Ni-Rich Layered Oxide Cathodes, Jianqing Zhao, Wei Zhang, Ashfia Huq, Scott T. Misture, Boliang Zhang, Shengmin Guo, Lijun Wu, Yimei Zhu, Zonghai Chen, Khalil Amine, Feng Pan, Jianming Bai, Feng Wang

Faculty Publications

Ni-rich layered oxides (LiNi1–xMxO2; M = Co, Mn, …) are appealing alternatives to conventional LiCoO2 as cathodes in Li-ion batteries for automobile and other large-scale applications due to their high theoretical capacity and low cost. However, preparing stoichiometric LiNi1–xMxO2 with ordered layer structure and high reversible capacity, has proven difficult due to cation mixing in octahedral sites. Herein, in situ studies of synthesis reactions and the associated structural ordering in preparing LiNiO2 and the Co-substituted variant, LiNi0.8Co0.2O2, are made, to gain insights into synthetic control of the structure and electrochemical properties of Ni-rich layered oxides. Results from this study indicate …


Distance-Dependent Measurements Of The Conductance Of Porphyrin Nanorods Studied With Conductive Probe Atomic Force Microscopy, Xianglin Zhai, Denzel Alexander, Pedro Derosa, Jayne C. Garno Feb 2017

Distance-Dependent Measurements Of The Conductance Of Porphyrin Nanorods Studied With Conductive Probe Atomic Force Microscopy, Xianglin Zhai, Denzel Alexander, Pedro Derosa, Jayne C. Garno

Faculty Publications

© 2017 American Chemical Society. Protocols for nanopatterning porphyrins on Au(111) were developed based on immersion particle lithography. Porphyrins with and without a central metal ion, 5,10,15,20-tetraphenyl-21H,23H-porphyrin (TPP) and 5,10,15,20-tetraphenyl-21H,23H-porphyrin cobalt(II) (CoTPP), were selected for study, which spontaneously formed nanorod geometries depending on concentration parameters. The elongated shapes of the nanorods offers an opportunity for successive distance-dependent conductive probe atomic force microscopy (CP-AFM) measurements along the length of the nanorods. To prepare patterns of TPP and CoTPP nanorods, a mask of silica mesospheres was placed on gold substrates to generate nanoholes within an alkanethiol matrix film. The nanoholes prepared by …


Excitation Wavelength Independent Visible Color Emission Of Carbon Dots, Hua Wang, Chun Sun, Xingru Chen, Yu Zhang, Vicki L. Colvin, Quinton Rice, Jaetae Seo, Shengyu Feng, Shengnian Wang, William W. Yu Feb 2017

Excitation Wavelength Independent Visible Color Emission Of Carbon Dots, Hua Wang, Chun Sun, Xingru Chen, Yu Zhang, Vicki L. Colvin, Quinton Rice, Jaetae Seo, Shengyu Feng, Shengnian Wang, William W. Yu

Faculty Publications

© 2017 The Royal Society of Chemistry. Carbon dots (CDs) usually emit a strong blue light and excitation wavelength dependent long wavelength lights. This significantly limits their applications because one has to use a series of different excitation light sources to get different colors and the long wavelength emissions are usually very weak. We found that one type of CDs synthesized from p-phenylenediamine could emit various long wavelength lights (green to red) independent of the excitation wavelength when dispersed in different solvents. The photoluminescence quantum yields of the same CDs were 10-35% in different solvents for different color emissions. Based …


Repeated Hapten Exposure Induces Persistent Tactile Sensitivity In Mice Modeling Localized Provoked Vulvodynia, Tijana Martinov, Jasmine Landry, Hanna Mengistu, Jyothi Dhanwada, Charles J. Benck, Jacyln Kline, Beebie Boo, Linnea Swanson, Elena Tonc, Randy Daughters, Brian T. Fife, Devavani Chatterjea Feb 2017

Repeated Hapten Exposure Induces Persistent Tactile Sensitivity In Mice Modeling Localized Provoked Vulvodynia, Tijana Martinov, Jasmine Landry, Hanna Mengistu, Jyothi Dhanwada, Charles J. Benck, Jacyln Kline, Beebie Boo, Linnea Swanson, Elena Tonc, Randy Daughters, Brian T. Fife, Devavani Chatterjea

Faculty Publications

BACKGROUND:
Vulvodynia is a remarkably prevalent chronic pain condition of unknown etiology. Epidemiologic studies associate the risk of vulvodynia with a history of atopic disease. We used an established model of hapten-driven contact hypersensitivity to investigate the underlying mechanisms of allergy-provoked prolonged sensitivity to pressure.

METHODS:
We sensitized female ND4 Swiss mice to the hapten oxazolone on their flanks, and subsequently challenged them four days later with oxazolone or vehicle for ten consecutive days on the labia. We evaluated labiar sensitivity to touch, local mast cell accumulation, and hyperinnervation after ten challenges.

RESULTS:
Oxazolone-challenged mice developed significant tactile sensitivity that …


Climate Warming Can Accelerate Carbon Fluxes Without Changing Soil Carbon Stocks, Susan E. Ziegler, Ronald Benner, Sharon A. Billings, Kate A. Edwards, Michael Philben, Xinbiao Zhu, Jerome Laganière Feb 2017

Climate Warming Can Accelerate Carbon Fluxes Without Changing Soil Carbon Stocks, Susan E. Ziegler, Ronald Benner, Sharon A. Billings, Kate A. Edwards, Michael Philben, Xinbiao Zhu, Jerome Laganière

Faculty Publications

Climate warming enhances multiple ecosystem C fluxes, but the net impact of changing C fluxes on soil organic carbon (SOC) stocks over decadal to centennial time scales remains unclear. We investigated the effects of climate on C fluxes and soil C stocks using space-for-time substitution along a boreal forest climate gradient encompassing spatially replicated sites at each of three latitudes. All regions had similar SOC concentrations and stocks (5.6 to 6.7 kg C m−2). The three lowest latitude forests exhibited the highest productivity across the transect, with tree biomass:age ratios and litterfall rates 300 and 125% higher than those in …


Bottom Redox Model (Brom V.1.1): A Coupled Benthic-Pelagic Model For Simulation Of Water And Sediment Biogeochemistry, Evgeniy V. Yakushev, Elizaveta A. Protsenko, Jorn Bruggeman, Philip Wallhead, Svetlana V. Pakhomova, Shamil Kh Yakubov, Richard G.J. Bellerby, Raoul Marie Couture Feb 2017

Bottom Redox Model (Brom V.1.1): A Coupled Benthic-Pelagic Model For Simulation Of Water And Sediment Biogeochemistry, Evgeniy V. Yakushev, Elizaveta A. Protsenko, Jorn Bruggeman, Philip Wallhead, Svetlana V. Pakhomova, Shamil Kh Yakubov, Richard G.J. Bellerby, Raoul Marie Couture

Faculty Publications

© Author(s) 2017. Interactions between seawater and benthic systems play an important role in global biogeochemical cycling. Benthic fluxes of some chemical elements (e.g., C, N, P, O, Si, Fe, Mn, S) alter the redox state and marine carbonate system (i.e., pH and carbonate saturation state), which in turn modulate the functioning of benthic and pelagic ecosystems. The redox state of the near-bottom layer in many regions can change with time, responding to the supply of organic matter, physical regime, and coastal discharge. We developed a model (BROM) to represent key biogeochemical processes in the water and sediments and to …


Geographic Variation In Apparent Competition Between Native And Invasive Phragmites Australis, Ganesh P. Bhattarai, Laura A. Meyerson, James T. Cronin Feb 2017

Geographic Variation In Apparent Competition Between Native And Invasive Phragmites Australis, Ganesh P. Bhattarai, Laura A. Meyerson, James T. Cronin

Faculty Publications

© 2016 by the Ecological Society of America. Apparent competition, the negative interaction between species mediated by shared natural enemies, is thought to play an important role in shaping the structure and dynamics of natural communities. However, its importance in driving species invasions, and whether the strength of this indirect interaction varies across the latitudinal range of the invasion, has not been fully explored. We performed replicated field experiments at four sites spanning 900 km along the Atlantic Coast of the United States to assess the presence and strength of apparent competition between sympatric native and invasive lineages of Phragmites …


Biogeography Of A Plant Invasion: Genetic Variation And Plasticity In Latitudinal Clines For Traits Related To Herbivory, Ganesh P. Bhattarai, Laura A. Meyerson, Jack Anderson, David Cummings, Warwick J. Allen, James T. Cronin Feb 2017

Biogeography Of A Plant Invasion: Genetic Variation And Plasticity In Latitudinal Clines For Traits Related To Herbivory, Ganesh P. Bhattarai, Laura A. Meyerson, Jack Anderson, David Cummings, Warwick J. Allen, James T. Cronin

Faculty Publications

© 2016 by the Ecological Society of America. The juxtaposition of plant-species invasions with latitudinal gradients in herbivore pressure is an important yet mostly unexplored issue in invasion biology. Latitudinal clines in defense and palatability to herbivores are expected to exist in native plant species but the evolution of these clines may lag behind for invasive plant species resulting in non-parallel latitudinal clines that may impact invasion success. Our study focused on a native and European invasive lineages of the common reed Phragmites australis in North America. Using native and invasive genotypes of P. australis collected across a 17° latitudinal …