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Articles 147601 - 147630 of 302657

Full-Text Articles in Physical Sciences and Mathematics

Tmco1 Mediates Cancer Cell Migration Through Regulating Microtubule Assembling, Pau Romaguera Llacer, Qiaoxia Zheng, Qiaoyun Zheng Jan 2015

Tmco1 Mediates Cancer Cell Migration Through Regulating Microtubule Assembling, Pau Romaguera Llacer, Qiaoxia Zheng, Qiaoyun Zheng

Undergraduate Research Posters 2015

Transmembrane and coiled-coil domains 1 (TMCO1) is highly conserved in amino acid sequence among species and ubiquitously expressed in all human tissues. Homozygous frameshift mutation in TMCO1 causes distinctive craniofacial dysmorphism, skeletal anomalies, and mental retardation. However, its physiological functions, particularly in cancer biology, are largely unknown. In this study, we have found that knock down of TMCO1 in HeLa cells, a human cervical cancer cell line, and U2OS cells, an osteosarcoma cell line, remarkably inhibited their migratory capability; TMCO1 was highly expressed in the cells of the invasive front of high grade lung cancer and metastatic cancer cells in …


Monitoring And Understanding Decadal Scale Changes In Hydrology, Productivity And Carbon Balance In Arctic Tundra Ponds, Christian Gerardo Andresen Jan 2015

Monitoring And Understanding Decadal Scale Changes In Hydrology, Productivity And Carbon Balance In Arctic Tundra Ponds, Christian Gerardo Andresen

Open Access Theses & Dissertations

The Arctic is known for containing large stocks of soil organic carbon, which exists frozen in permafrost in a greenhouse inert state. With predicted future warming in these high northern latitudes, the mobilization of stored soil organic carbon and release to the atmosphere may increase and induce further positive climatic feedbacks. Previous studies have shown that Arctic wetlands and ponds cover a large percentage of the Arctic Coastal Plain and contribute large amounts of carbon to the atmosphere; however, it remains largely unknown how these systems are responding to a warming climate and how this change will impact regional carbon …


Associativity Forcing Commutativity In Left Nil Rings, Md Al Masum Bhuiyan Jan 2015

Associativity Forcing Commutativity In Left Nil Rings, Md Al Masum Bhuiyan

Open Access Theses & Dissertations

Our study in this thesis is concentrated on the AFC groups (Associativity Forces Commutativity) and observing the ring structure there. We are looking for abelian groups yielding ring structures (K) where associativity forces commutativity. We call them K-AFC groups.

We consider that the only conditions put on a ring multiplication are the distributive laws over the additive group addition. After [1], We say that an abelian group (G, +) is an AFC-group if (i) there exists a nonassociative and noncommutative ring (G, +, ˙) and (ii) all associative rings (G, +, ˙) are commutative.

We call a ring left-nil if …


Quantifying Weathering Rates On Tropical Volcanic Basse-Terre Island, French Guadeloupe: Insights From U-Series Isotopes In Weathering Rinds, Jacqueline Engel Jan 2015

Quantifying Weathering Rates On Tropical Volcanic Basse-Terre Island, French Guadeloupe: Insights From U-Series Isotopes In Weathering Rinds, Jacqueline Engel

Open Access Theses & Dissertations

Weathering of volcanic rocks plays many important roles at Earth’s surface such as modifying landscapes, providing nutrients to soil, and regulating atmospheric CO2. U-series isotopes (e.g. 238U-234U-230Th and 232Th) have been established as a chronometer used to constrain the formation rates of weathering rinds in tropical island environments. Here, U-series isotopes and major element concentrations were analyzed in two basaltic-andesite weathering rinds collected from the Deshaies watershed located in the northern, relatively dry (mean annual precipitation (MAP) = 1800 mm) region of tropical Basse-Terre Island, Guadeloupe. The two clasts are referred to as clasts AN-14-7.5 and AN-14-7.6. Elemental mobility trends …


Receiver Function Analysis To Study Crustal Structure Of The Northern Nepal And Tibetan Plateau, Mohan Pant Jan 2015

Receiver Function Analysis To Study Crustal Structure Of The Northern Nepal And Tibetan Plateau, Mohan Pant

Open Access Theses & Dissertations

The teleseismic P-waveform receiver function analysis is a commonly used technique in earthquake seismology to study the crustal structure beneath a broadband seismic station. To understand the structure of the Northern Nepal and Tibetan plateau different studies have used the receiver function method to estimate the Moho depth and Vp/Vs ratio. The value suggested was ~ 30 km in the south and the ~ 75 km in the north. Other studies have used teleseismic body wave data to perform the travel time residuals to model the lithosphere structure. In our study, we analyzed data from 261 seismic stations to establish …


An Economic Analysis Of Mars Exploration And Colonization, Clayton Knappenberger 15 Jan 2015

An Economic Analysis Of Mars Exploration And Colonization, Clayton Knappenberger 15

Honor Scholar Theses

No abstract provided.


Stormwater Management And Residents Perceptions, Mark Gatesman Jan 2015

Stormwater Management And Residents Perceptions, Mark Gatesman

Undergraduate Research Posters 2015

Stormwater runoff is a major problem in many residential municipalities. Rain water washes pollutants and chemicals off of streets, driveways and lawns. Stormwater management practices help filter out harmful particles before they enter into our water ways. The goal of this project was to assess green infrastructure stormwater practices throughout Cuyahoga County. We assessed 165 sites in over 10 cities in Cuyahoga County. We examined bioswales, bioretention basins, and rain gardens. Sites were visited in late May through early June and revisited in mid-July to early August. We compared spring condition of plants and gardens and recorded resident’s perceptions whether …


Synthesis Of Optimal Polymeric Microgels And Their Characterization With Light Scattering, Christan Gunder, Daria Kulyk Jan 2015

Synthesis Of Optimal Polymeric Microgels And Their Characterization With Light Scattering, Christan Gunder, Daria Kulyk

Undergraduate Research Posters 2015

Polymeric microgels were synthesized in by chemically crosslinking hydroxypropylcellulose (HPC) chains with each other in aqueous solutions of sodium hydroxide at temperatures above the low solution critical temperature (LCST) of HPC. In order to create a narrower size distribution of HPC microgels, surfactant (dodecyltrimethylammonium bromide, DTAB) was added. It was found that, LCST of the solution moved from ~40C up to 80C with an increase in DTAB concentration from 0 to 12 g/l. Formed microgels were be characterized by dynamic light scattering (DLS). Microgel solutions synthesized so far resulted in reasonably monodispersed nanoparticles between the sizes of 150-90 nm below …


Origin, Evolution, And Tectonic Setting Of The Eastern Part Of The Mexican Volcanic Belt And Comparison With The Central American Volcanic Arc From Conventional Multielement Normalized And New Multidimensional Discrimination Diagrams And Discordancy And Significance Tests, Surendra P. Verma Jan 2015

Origin, Evolution, And Tectonic Setting Of The Eastern Part Of The Mexican Volcanic Belt And Comparison With The Central American Volcanic Arc From Conventional Multielement Normalized And New Multidimensional Discrimination Diagrams And Discordancy And Significance Tests, Surendra P. Verma

Turkish Journal of Earth Sciences

If both the Mexican Volcanic Belt (MVB) and the Central American Volcanic Arc (CAVA) have been related to the subduction of the Cocos plate beneath the North American and Caribbean plates, respectively, their magmas, and especially the less evolved basic varieties, should show considerable similarities. The conventional multielement normalized diagrams indicate more complex petrogenetic processes for the MVB than the CAVA. Forty-five statistically coherent tectonomagmatic discrimination diagrams were used to infer the tectonic setting of the controversial geological subprovince of the eastern part of the MVB (E-MVB). Basic rocks from the E-MVB indicated a continental rift setting, whereas the intermediate …


Empirical M X-Ray Production Cross Sections For Heavy Elements By Proton Impact Within Z-Dependence Analysisempirical M X-Ray Production Cross Sections For Heavy Elements By Proton Impact Within Z-Dependence Analysis, Bahri Deghfel, Farid Khalfallah, Abdelhalim Kahoul, Mohammed Nekkab Jan 2015

Empirical M X-Ray Production Cross Sections For Heavy Elements By Proton Impact Within Z-Dependence Analysisempirical M X-Ray Production Cross Sections For Heavy Elements By Proton Impact Within Z-Dependence Analysis, Bahri Deghfel, Farid Khalfallah, Abdelhalim Kahoul, Mohammed Nekkab

Turkish Journal of Physics

New empirical M-shell X-ray production cross sections have been deduced by introducing the dependence of the universal trend of the experimental data on the atomic number of the target, noted as "Z-dependence" for semiempirical cross sections in our previous work. For this effect, the updated experimental data (from 1980 to 2009) are used to calculate the empirical cross sections for heavy elements with 60 $\le $ Z $\le $ 90 by proton impact. Finally, a comparison is made between the deduced results and other earlier works.


Kinematic Barrier Constraints On The Magnitudes Of Additional Great Earthquakes Off The East Coast Of Japan, John P. Loveless, Brendan J. Meade Jan 2015

Kinematic Barrier Constraints On The Magnitudes Of Additional Great Earthquakes Off The East Coast Of Japan, John P. Loveless, Brendan J. Meade

Geosciences: Faculty Publications

No abstract provided.


Taphonomic Bias Of Selective Silicification Revealed By Paired Petrographic And Insoluble Residue Analysis, Sara B. Pruss, Jonathan L. Payne, Sophie Westacott Jan 2015

Taphonomic Bias Of Selective Silicification Revealed By Paired Petrographic And Insoluble Residue Analysis, Sara B. Pruss, Jonathan L. Payne, Sophie Westacott

Geosciences: Faculty Publications

Silicification is an important mode of fossil preservation but the extent to which silicified material represents an unbiased sampling of the total fossil assemblage within a given rock sample remains poorly quantified. Here, we use paired analyses of thin sections and acid-extracted silicified specimens from the same samples to examine the biases introduced during silicification of Lower Triassic Virgin Limestone carbonates preserved in the Muddy Mountains of southern Nevada. Bivalves dominate most thin sections in the point count data, but rarely silicify completely enough to be recognized in residue. Echinoderms and gastropods are less abundant in thin section but dominate …


Novel Incorportation Of Biomedical Engineering Algorithms (Bispectral Index Guided Or Anesthetic Concentration Guided) In Real-Time Decision Support To Prevent Intraoperative Awareness Using An Electronic Anesthesia Information Mananagement System, Amy Melanie Shanks Jan 2015

Novel Incorportation Of Biomedical Engineering Algorithms (Bispectral Index Guided Or Anesthetic Concentration Guided) In Real-Time Decision Support To Prevent Intraoperative Awareness Using An Electronic Anesthesia Information Mananagement System, Amy Melanie Shanks

Wayne State University Dissertations

Background: Intraoperative awareness with explicit recall (AWR) is a feared complication of surgery that can lead to significant psychological distress. Several large prospective trials have been completed comparing two methods of monitoring anesthetic depth [minimum alveolar concentration (MAC) or electroencephalography (EEG) monitoring using the bispectral index (BIS)] for the prevention of AWR. However, these trials were conducted in high risk populations, limiting generalizability.

Research Hypothesis: Real-time decision support with Anesthesia Information Management System alerts based on a novel anesthetic concentration algorithm (incorporating the use of intravenous anesthetics) or an EEG-guided algorithm will reduce the known incidence of AWR.

Methods: First, …


Enhancement In Electrochemical Performance Of Advanced Battery Electrodes Using Carbon- Nanomaterial Composites, Kulwinder Dhindsa Jan 2015

Enhancement In Electrochemical Performance Of Advanced Battery Electrodes Using Carbon- Nanomaterial Composites, Kulwinder Dhindsa

Wayne State University Dissertations

LiFePO4 has attracted great interest as a cathode material for lithium ion batteries due to its reasonably high theoretical capacity (170mAh/g), thermal stability, high Li ion reversibility and low cost. However, prohibitively low electronic conductivity (~10-9 S/cm) of LiFePO4 leads to high impedance, low capacity and low rate capability. To overcome this bottleneck, we have developed multiple approaches to improve the conductivity of LiFePO4. Motivated by the outstanding electronic and mechanical properties as well as high surface area of graphene, we prepared LiFePO4/graphene nano-composites by a sol-gel method. The phase purity of the nano LiFePO4/Graphene composite was confirmed by X-Ray …


Classical And Ab Initio Qm/Mm Simulations Of Bacterial Enzymes, Sajeewa Walimuni Dewage Jan 2015

Classical And Ab Initio Qm/Mm Simulations Of Bacterial Enzymes, Sajeewa Walimuni Dewage

Wayne State University Dissertations

This thesis describes analyses performed on three enzyme systems. Chapter 2, 3, and 4 involve studies carried out on the GatCAB enzyme of H. pylori and S. aureus. Since information at the electronic level was not required for these studies, sampling of the configuration space carried out at the molecular mechanics level was adequate. In Chapter 2, the snapshots sampled using MD were used as input for average correlation difference calculations and average RMSD difference calculations to ascertain the existence of a communication pathway between two subunits of GatCAB. Experimental and computational results obtained, suggest the existence of a communication …


Frequency Domain Ultrasound Waveform Tomography Breast Imaging, Gursharan Singh Sandhu Jan 2015

Frequency Domain Ultrasound Waveform Tomography Breast Imaging, Gursharan Singh Sandhu

Wayne State University Dissertations

Ultrasound tomography is an emerging modality for imaging breast tissue for the detection of disease. Using the principles of full waveform inversion, high-resolution quantitative sound speed and attenuation maps of the breast can be created. In this thesis, we introduce some basic principles of imaging breast disease and the formalism of sound wave propagation. We present numerical methods to model acoustic wave propagation as well methods to solve the corresponding inverse problem. Numerical simulations of sound speed and attenuation reconstructions are used to assess the efficacy of the algorithm. A careful review of the preprocessing techniques needed for the successful …


Recovery Techniques For Finite Element Methods And Their Applications, Hailong Guo Jan 2015

Recovery Techniques For Finite Element Methods And Their Applications, Hailong Guo

Wayne State University Dissertations

Recovery techniques are important post-processing methods to obtain improved approximate solutions from primary data with reasonable cost. The practical us- age of recovery techniques is not only to improve the quality of approximation, but also to provide an asymptotically exact posteriori error estimators for adaptive meth- ods. This dissertation presents recovery techniques for nonconforming finite element methods and high order derivative as well as applications of gradient recovery.

Our first target is to develop a systematic gradient recovery technique for Crouzeix- Raviart element. The proposed method uses finite element solution to build a better approximation of the exact gradient based …


Augite In Komatiitic Basalts: A Study Of The Mobility Of Trace Elements During Rock Alteration, Alesha C. Morabito Jan 2015

Augite In Komatiitic Basalts: A Study Of The Mobility Of Trace Elements During Rock Alteration, Alesha C. Morabito

LSU Master's Theses

Komatiitic basalts are ultramafic rocks formed from volcanic liquids containing less than 18 wt.% magnesium oxide that can be linked, spatially, geochemically and texturally to komatiites. Archean komatiites and komatiitic basalts are critical to models of early Earth’s mantle evolution. Major and trace elements in these rocks are poorly preserved due to early sub-seafloor alteration with superimposed regional metamorphism: in particular the alkali, alkaline earths, and other elements with low valence numbers. Current analytical methods focus on analyzing whole rock, fresh olivines and melt inclusions to evaluate elemental concentrations and for petrogenetic studies. Although these methods establish elemental concentrations, REE, …


A Study Of Resiliency In New Orleans Neighborhoods Ten Years After Hurricane Katrina, Paul Ramnauth Algu Jan 2015

A Study Of Resiliency In New Orleans Neighborhoods Ten Years After Hurricane Katrina, Paul Ramnauth Algu

LSU Master's Theses

Hurricane Katrina made landfall on August 29, 2005, flooding over eighty percent of the Greater New Orleans area and causing a mass exodus of the local population. Statistical analysis was used to quantify recovery at a neighborhood level and answer the following questions: What is the recovery rate of New Orleans neighborhoods ten years after Hurricane Katrina? What factors account for variation in recovery rates among neighborhoods? Six neighborhoods in Orleans Parish were selected for further study based on their unique geographical and recovery metrics. Recovery rates among the seventy-two neighborhoods were based on a comparison of United States Postal …


Mining User Viewpoints In Online Discussions, Minghui Qiu Jan 2015

Mining User Viewpoints In Online Discussions, Minghui Qiu

Dissertations and Theses Collection (Open Access)

Online discussion forums are a type of social media which contains rich usercontributed facts, opinions, and user interactions on diverse topics. The large volume of opinionated data generated in online discussions provides an ideal testbed for user opinion mining. In particular, mining user opinions on social and political issues from online discussions is useful not only to government organizations and companies but also to social and political scientists. In this dissertation, we propose to study the task of mining user viewpoints or stances from online discussions on social and political issues. Specifically, we will talk about our proposed approaches for …


Guidance Counselor Survey, Chery Justice, Kathleen Sherman-Morris, Kimberly Hall Jan 2015

Guidance Counselor Survey, Chery Justice, Kathleen Sherman-Morris, Kimberly Hall

College of Arts and Sciences Publications and Scholarship

This is a survey created to study guidance/career counselor opinions about the geosciences and other STEM fields, and the career counseling activities they use.


Imaging, Spectroscopy, Mechanical, Alignment And Biocompatibility Studies Of Electrospun Medical Grade Polyurethane (Carbothane™ 3575a) Nanofibers And Composite Nanofibers Containing Multiwalled Carbon Nanotubes, Faheem A. Sheikh, Javier Macossay-Torres, Travis Cantu, Xujun Zhang, M. Shamshi Hassan, M. Esther Salinas, Chakavak S. Farhangi, Hassan Ahmad, Hern Kim, Gary L. Bowlin Jan 2015

Imaging, Spectroscopy, Mechanical, Alignment And Biocompatibility Studies Of Electrospun Medical Grade Polyurethane (Carbothane™ 3575a) Nanofibers And Composite Nanofibers Containing Multiwalled Carbon Nanotubes, Faheem A. Sheikh, Javier Macossay-Torres, Travis Cantu, Xujun Zhang, M. Shamshi Hassan, M. Esther Salinas, Chakavak S. Farhangi, Hassan Ahmad, Hern Kim, Gary L. Bowlin

Chemistry Faculty Publications and Presentations

In the present study, we discuss the electrospinning of medical grade polyurethane (Carbothane™ 3575A) nanofibers containing multi-walled-carbon-nanotubes (MWCNTs). A simple method that does not depend on additional foreign chemicals has been employed to disperse MWCNTs through high intensity sonication. Typically, a polymer solution consisting of polymer/MWCNTs has been electrospun to form nanofibers. Physiochemical aspects of prepared nanofibers were evaluated by SEM, TEM, FT-IR and Raman spectroscopy, confirming nanofibers containing MWCNTs. The biocompatibility and cell attachment of the produced nanofiber mats were investigated while culturing them in the presence of NIH 3T3 fibroblasts. The results from these tests indicated non-toxic behavior …


An Acid-Bath Technique To Break Seed Dormancy In Common Sunflower, Helianthus L. Annuus (Asteraceae), Yuridia Patricia Gandy, Michael W. Persans, Kenneth R. Summy Jan 2015

An Acid-Bath Technique To Break Seed Dormancy In Common Sunflower, Helianthus L. Annuus (Asteraceae), Yuridia Patricia Gandy, Michael W. Persans, Kenneth R. Summy

Chemistry Faculty Publications and Presentations

The phenomenon of seed dormancy is widespread in plants and serves to prevent all or most of a given population from germinating at the “wrong” time, e.g., during an unusually mild fall in an area subject to typically harsh winters. Seed dormancy is an effective survival strategy in many plant populations, but may greatly complicate efforts to establish large cohorts of seedlings (groups of similar age or developmental stage) needed for re-search and other purposes. In an effort to break seed dormancy in common sunflower, Helianthus annuus L. (Asteraceae), we conducted experiments designed to compare germination times and overall germination …


Applying Hierarchical Task Analysis Method To Discovery Layer Evaluation, Marlen Promann, Tao Zhang Jan 2015

Applying Hierarchical Task Analysis Method To Discovery Layer Evaluation, Marlen Promann, Tao Zhang

Libraries Faculty and Staff Scholarship and Research

While usability tests have been helpful in evaluating the success or failure of implementing discovery layers in the library context, the focus of usability tests has remained on the search interface rather than the discovery process for users. The informal site-­‐ and context specific usability tests have offered little to test the rigor of the discovery layers against the user goals, motivations and workflow they have been designed to support. This study proposes hierarchical task analysis (HTA) as an important complementary evaluation method to usability testing of discovery layers. Relevant literature is reviewed for the discovery layers and the HTA …


Changing Cpu Frequency In Comd Proxy Application Offloaded To Intel Xeon Phi Co-Processors, Gary Lawson, Masha Sosonkina, Yuzhong Shen Jan 2015

Changing Cpu Frequency In Comd Proxy Application Offloaded To Intel Xeon Phi Co-Processors, Gary Lawson, Masha Sosonkina, Yuzhong Shen

Computational Modeling & Simulation Engineering Faculty Publications

Obtaining exascale performance is a challenge. Although the technology of today features hardware with very high levels of concurrency, exascale performance is primarily limited by energy consumption. This limitation has lead to the use of GPUs and specialized hardware such as many integrated core (MIC) co-processors and FPGAs for computation acceleration. The Intel Xeon Phi co-processor, built upon the MIC architecture, features many low frequency, energy efficient cores. Applications, even those which do not saturate the large vector processing unit in each core, may benefit from the energy-efficient hardware and software of the Xeon Phi. This work explores the energy …


Potential Of Cognitive Computing And Cognitive Systems, Ahmed K. Noor Jan 2015

Potential Of Cognitive Computing And Cognitive Systems, Ahmed K. Noor

Computational Modeling & Simulation Engineering Faculty Publications

Cognitive computing and cognitive technologies are game changers for future engineering systems, as well as for engineering practice and training. They are major drivers for knowledge automation work, and the creation of cognitive products with higher levels of intelligence than current smart products. This paper gives a brief review of cognitive computing and some of the cognitive engineering systems activities. The potential of cognitive technologies is outlined, along with a brief description of future cognitive environments, incorporating cognitive assistants - specialized proactive intelligent software agents designed to follow and interact with humans and other cognitive assistants across the environments. The …


Iron Deficiency Increases Growth And Nitrogen-Fixation Rates Of Phosphorus-Deficient Marine Cyanobacteria, Nathan S. Garcia, Feixue Fu, Peter N. Sedwick, David A. Hutchins Jan 2015

Iron Deficiency Increases Growth And Nitrogen-Fixation Rates Of Phosphorus-Deficient Marine Cyanobacteria, Nathan S. Garcia, Feixue Fu, Peter N. Sedwick, David A. Hutchins

OES Faculty Publications

Marine dinitrogen (N2)-fixing cyanobacteria have large impacts on global biogeochemistry as they fix carbon dioxide (CO2) and fertilize oligotrophic ocean waters with new nitrogen. Iron (Fe) and phosphorus (P) are the two most important limiting nutrients for marine biological N2 fixation, and their availabilities vary between major ocean basins and regions. A long-standing question concerns the ability of two globally dominant N2-fixing cyanobacteria, unicellular Crocosphaera and filamentous Trichodesmium, to maintain relatively high N2-fixation rates in these regimes where both Fe and P are typically scarce. We show that under P-deficient …


Characterization Of Terrestrial Dissolved Organic Matter Fractionated By Ph And Polarity And Their Biological Effects On Plant Growth, Rachel L. Sleighter, Paolo Caricasole, Kristen M. Richards, Terry Hanson, Patrick G. Hatcher Jan 2015

Characterization Of Terrestrial Dissolved Organic Matter Fractionated By Ph And Polarity And Their Biological Effects On Plant Growth, Rachel L. Sleighter, Paolo Caricasole, Kristen M. Richards, Terry Hanson, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Background: Humic substances are ubiquitous in the environment, complex mixtures, and known to be beneficial to plant growth. To better understand and identify components responsible for plant growth stimulation, a terrestrial aquatic DOM sample was fractionated according to pH and polarity, obtaining acid-soluble and acid-insoluble portions, as well as acid-soluble hydrophobic and hydrophilic fractions using C18. The various fractions were characterized then evaluated for their biological effects on plant growth using bioassays with corn at two carbon rates.

Results: Approximately 43% and 57% of the carbon, and 31% and 69% of the iron, was found in the acid-insoluble and acid-soluble …


Proton-Electrostatic Localization: Explaining The Bioenergetic Conundrum In Alkalophilic Bacteria, James Weifu Lee Jan 2015

Proton-Electrostatic Localization: Explaining The Bioenergetic Conundrum In Alkalophilic Bacteria, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

The decades-longstanding energetic conundrum of alkalophilic bacteria as to how they are able to synthesize ATP has now, for the first time, been clearly solved using the proton-electrostatics localization hypothesis. This is a major breakthrough advance in understanding proton-coupling bioenergetics over the Nobel-prize work of Peter Mitchell’s chemiosmotic theory. The widespread textbook Mitchellian proton motive force (pmf) equation has now been significantly revised. Use of the newly derived equation results in an overall pmf value (215~233 mV) that is more than 4 times larger than that (44.3 mV) calculated from the Mitchellian equation for the alkalophilic bacteria growing at pH …


The Relative Importance Of Methanogenesis In The Decomposition Of Organic Matter In Northern Peatlands, J. Elizabeth Corbett, Malak M. Tfaily, David J. Burdige, Paul H. Glaser, Jeffrey P. Chanton Jan 2015

The Relative Importance Of Methanogenesis In The Decomposition Of Organic Matter In Northern Peatlands, J. Elizabeth Corbett, Malak M. Tfaily, David J. Burdige, Paul H. Glaser, Jeffrey P. Chanton

OES Faculty Publications

Using an isotope-mass balance approach and assuming the equimolar production of CO2 and CH4 from methanogenesis (e.g., anaerobic decomposition of cellulose), we calculate that the proportion of total CO2 production from methanogenesis varies from 37 to 83% across a variety of northern peatlands. In a relative sense, methanogenesis was a more important pathway for decomposition in bogs (80 ± 13% of CO2 production) than in fens (64 ± 5.7% of CO2 production), but because fens contain more labile substrates they may support higher CH4 production overall. The concentration of CO2 produced from methanogenesis (CO …