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African Land Mammal Ages, John Van Couvering, Eric Delson Dec 2020

African Land Mammal Ages, John Van Couvering, Eric Delson

Publications and Research

We define 17 African land mammal ages, or AFLMAs, covering the Cenozoic record of the Afro-arabian continent, the planet’s second largest land mass. While fossiliferous deposits are absent on the eroded plateau of the continent’s interior, almost 800 fossil genera from over 350 locations have now been identified in coastal deposits, karst caves, and in the Neogene rift valleys. Given a well-developed geochronologic framework, together with continuing revision to the fossil record—both stimulated by the story of human evolution in Africa—and also to compensate for the variation in fossil ecosystems across such great distances, the AFLMAs are biochronological units defined …


A Conceptual Model Evaluation Framework For Adaptive Governance And Adaptive Management In Large-Scale Restoration Programs, Chadwin Smith Dec 2020

A Conceptual Model Evaluation Framework For Adaptive Governance And Adaptive Management In Large-Scale Restoration Programs, Chadwin Smith

School of Natural Resources: Dissertations, Theses, and Student Research

Adaptive management (AM) has become a kind of plastic phrase applied as a formulaic panacea for most major species recovery and ecosystem restoration efforts now underway across the United States. AM emerged as an application of the scientific method to resource management, closely tying management to science learning through experimental actions. The phrase “learning by doing” best captures the premise behind developing an experimental management approach that could be applied on the larger scale of a river system or ecosystem. In nearly five decades of application, however, examples of successful AM implementation at large scales are few and conflict remains …


Short And Long Term Effects Of Lime And Gypsum Applications On Acid Soils In A Water-Limited Environment: 2. Soil Chemical Properties, Geoff Anderson, Shahab Pathan, James Easton, David Hall, Rajesh Sharma Dec 2020

Short And Long Term Effects Of Lime And Gypsum Applications On Acid Soils In A Water-Limited Environment: 2. Soil Chemical Properties, Geoff Anderson, Shahab Pathan, James Easton, David Hall, Rajesh Sharma

Grain and Other Field Crops Research Articles

Soil acidity or aluminum (Al) toxicity is a major limitation to crop production. In this paper, we examine the effects of surface-applied lime and gypsum on soil profile chemical properties that affect Al toxicity in short-term (1 year), medium-term (2 years and 8 months) and long-term (10 years) experiments. Sulfate applied to the soil surface as gypsum was leached rapidly to a depth of 40 cm in the short-term despite relatively low amounts (279 mm) of rainfall. In the medium and long-term experiments, 28–54% of the sulfate applied as gypsum was retained in the 0–50 cm soil layer due to …


3d Numerical Simulation-Based Targeting Of Skarn Type Mineralization Within The Xuancheng-Magushan Orefield, Middle-Lower Yangtze Metallogenic Belt, China, Xunyu Hu, Xiaohui Li, Feng Yuan, Simon M. Jowitt, Alison Ord, Rui Ye, Yue Li, Wenqiang Dai, Xiangling Li Dec 2020

3d Numerical Simulation-Based Targeting Of Skarn Type Mineralization Within The Xuancheng-Magushan Orefield, Middle-Lower Yangtze Metallogenic Belt, China, Xunyu Hu, Xiaohui Li, Feng Yuan, Simon M. Jowitt, Alison Ord, Rui Ye, Yue Li, Wenqiang Dai, Xiangling Li

Geoscience Faculty Research

Recent exploration has identified a series of Cu-Mo skarn deposits within the Xuancheng-Magushan orefield. The orefield forms part of the Nanling-Xuancheng mining district, which is located within the Middle-Lower Yangtze River Metallogenic Belt (MLYRMB) of central-eastern China. However, this area contains thick and widespread unprospective sedimentary cover sequences that have impeded traditional approaches to mineral exploration. This study presents the results of 3D numerical simulation modeling that identifies possible mineral exploration targets within the entire Xuancheng-Magushan orefield. This modeling enables the identification of unexplored areas with significant exploration potential that are covered by thick sedimentary sequences that cannot be easily …


A Survey On Subsurface Signal Propagation, Usman Raza, Abdul Salam Dec 2020

A Survey On Subsurface Signal Propagation, Usman Raza, Abdul Salam

Faculty Publications

Wireless Underground Communication (WUC) is an emerging field that is being developed continuously. It provides secure mechanism of deploying nodes underground which shields them from any outside temperament or harsh weather conditions. This paper works towards introducing WUC and give a detail overview of WUC. It discusses system architecture of WUC along with the anatomy of the underground sensor motes deployed in WUC systems. It also compares Over-the-Air and Underground and highlights the major differences between the both type of channels. Since, UG communication is an evolving field, this paper also presents the evolution of the field along with the …


Core Handling, Transportation And Processing For The South Pole Ice Core (Spicecore) Project, Joseph M. Souney, Mark S. Twickler, Murat Aydin, Eric J. Steig, T.J. Fudge, Leah V. Street, Melinda R. Nicewonger, Emma C. Kahle, Jay A. Johnson, Tanner W. Kuhl, Kimberly A. Casey, John M. Fegyveresi, Richard M. Nunn, Geoffrey M. Hargreaves Dec 2020

Core Handling, Transportation And Processing For The South Pole Ice Core (Spicecore) Project, Joseph M. Souney, Mark S. Twickler, Murat Aydin, Eric J. Steig, T.J. Fudge, Leah V. Street, Melinda R. Nicewonger, Emma C. Kahle, Jay A. Johnson, Tanner W. Kuhl, Kimberly A. Casey, John M. Fegyveresi, Richard M. Nunn, Geoffrey M. Hargreaves

Earth Systems Research Center

An intermediate-depth (1751 m) ice core was drilled at the South Pole between 2014 and 2016 using the newly designed US Intermediate Depth Drill. The South Pole ice core is the highest-resolution interior East Antarctic ice core record that extends into the glacial period. The methods used at the South Pole to handle and log the drilled ice, the procedures used to safely retrograde the ice back to the National Science Foundation Ice Core Facility (NSF-ICF), and the methods used to process and sample the ice at the NSF-ICF are described. The South Pole ice core exhibited minimal brittle ice, …


Building An Improved Drought Climatology Using Updated Drought Tools: A New Mexico Food-Energy-Water (Few) Systems Focus, Lindsay E. Johnson, Hatim M.E. Geli, Michael J. Hayes, Kelly Helm Smith Dec 2020

Building An Improved Drought Climatology Using Updated Drought Tools: A New Mexico Food-Energy-Water (Few) Systems Focus, Lindsay E. Johnson, Hatim M.E. Geli, Michael J. Hayes, Kelly Helm Smith

Drought Mitigation Center: Faculty Publications

Drought is a familiar climatic phenomenon in the United States Southwest, with complex human-environment interactions that extend beyond just the physical drought events. Due to continued climate variability and change, droughts are expected to become more frequent and/or severe in the future. Decision-makers are charged with mitigating and adapting to these more extreme conditions and to do that they need to understand the specific impacts drought has on regional and local scales, and how these impacts compare to historical conditions. Tremendous progress in drought monitoring strategies has occurred over the past several decades, with more tools providing greater spatial and …


An Assessment Of The Hydrological Trends Using Synergistic Approaches Of Remote Sensing And Model Evaluations Over Global Arid And Semi-Arid Regions, Wenzhao Li, Hesham El-Askary, Rejoice Thomas, Surya Prakash Tiwari, Karuppasamy Manikandan, Thomas Piechota, Daniele Struppa Dec 2020

An Assessment Of The Hydrological Trends Using Synergistic Approaches Of Remote Sensing And Model Evaluations Over Global Arid And Semi-Arid Regions, Wenzhao Li, Hesham El-Askary, Rejoice Thomas, Surya Prakash Tiwari, Karuppasamy Manikandan, Thomas Piechota, Daniele Struppa

Mathematics, Physics, and Computer Science Faculty Articles and Research

Drylands cover about 40% of the world’s land area and support two billion people, most of them living in developing countries that are at risk due to land degradation. Over the last few decades, there has been warming, with an escalation of drought and rapid population growth. This will further intensify the risk of desertification, which will seriously affect the local ecological environment, food security and people’s lives. The goal of this research is to analyze the hydrological and land cover characteristics and variability over global arid and semi-arid regions over the last decade (2010–2019) using an integrative approach of …


Epithermal Mineralization Of The Bonanza-Sandy Vein System, Masara Gold District, Mindanao, Philippines, Jilian Aira S. Gabo-Ratio, Alfred Elmer Buena, Barbie Ross B. Villaplaza, Betchaida D. Payot, Carla B. Dimalanta, Karlo L. Queaño, Eric A. Andal, Graciano P. Yumul Jr Dec 2020

Epithermal Mineralization Of The Bonanza-Sandy Vein System, Masara Gold District, Mindanao, Philippines, Jilian Aira S. Gabo-Ratio, Alfred Elmer Buena, Barbie Ross B. Villaplaza, Betchaida D. Payot, Carla B. Dimalanta, Karlo L. Queaño, Eric A. Andal, Graciano P. Yumul Jr

Environmental Science Faculty Publications

The Masara Gold District in southeastern Mindanao island is an area of prolific hydrothermal copper and gold mineralization. This study documents the mineralization characteristics of the NW-trending Bonanza-Sandy epithermal veins to constrain possible hydrothermal fluid sources and ore-forming mechanisms. Epithermal mineralization in the NW veins is divided into three main stages: Stage 1 - massive quartz-sulfide; Stage 2 - massive to amorphous quartz-carbonate (calcite); and Stage 3 - colloform-cockade quartz-carbonate (bladed rhodochrosite). Stage 1 is the main gold mineralization phase, with chalcopyrite, pyrite, sphalerite and galena occurring with native gold and tellurides. Stages 2 and 3 contain invisible gold in …


Geochemistry, Petrology, And Palynology Of The Princess No. 3 Coal, Greenup County, Kentucky, Madison M. Hood, Cortland F. Eble, James C. Hower, Shifeng Dai Dec 2020

Geochemistry, Petrology, And Palynology Of The Princess No. 3 Coal, Greenup County, Kentucky, Madison M. Hood, Cortland F. Eble, James C. Hower, Shifeng Dai

Center for Applied Energy Research Faculty and Staff Publications

The high volatile C bituminous-rank, Bolsovian-age Princess No. 3 coal, a correlative of the heavily-mined Hazard No. 7 coal and the Peach Orchard and Coalburg Lower Split coals, was investigated three sites at a mine in Greenup County, Kentucky. The coal exhibits a “dulling upwards” trend, with decreasing vitrinite and a greater tendency towards dull clarain and bone lithotypes towards the top of the coal. The relatively vitrinite-rich basal lithotype is marked by a dominance of lycopod tree spores. The palynology transitions upwards to a middle parting co-dominated by tree fern and small lycopod spores and an upper bench dominated …


Mexican Obsidian On Maui: Hawaiian Connection, Harmonic Convergence, Or Hokum?, Matthew Boulanger Dec 2020

Mexican Obsidian On Maui: Hawaiian Connection, Harmonic Convergence, Or Hokum?, Matthew Boulanger

Anthropology Research

In 2014, the television show America Unearthed (A & E Networks) featured an episode discussing evidence for pre-Columbian contact between Polynesia and continental North and South America. Included in this “evidence” was a large spearpoint, allegedly found on the island of Maui. The show’s host argues that the spearpoint is made on obsidian from central Mexico, and therefore represents evidence for direct contact between Polynesian and Maya peoples prior to the sixteenth century CE. A detailed analysis of the spearpoint, including geochemical sourcing, reveals that it is indeed made of so-called Pachuca obsidian from central Mexico; however, the size, shape, …


Bioconversion Of Industrial Hemp Biomass For Bioethanol Production: A Review, Jikai Zhao, Youjie Xu, Weiqun Wang, Jason Griffin, Kraig Roozeboom, Donghai Wang Dec 2020

Bioconversion Of Industrial Hemp Biomass For Bioethanol Production: A Review, Jikai Zhao, Youjie Xu, Weiqun Wang, Jason Griffin, Kraig Roozeboom, Donghai Wang

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Industrial hemp (Cannabis sativa L.) with robust drought-resistant features has excellent agronomic and pharmaceutical characteristics. As the federal prohibition on hemp cultivation was lifted, its valorization in various aspects is highly required. This review aims to summarize the potential of hemp biomass for bioethanol production. Chemical compositions of hemp biomass were evaluated as compared with those of corn fiber, corn stover, and sorghum bagasse. Several representative pretreatment technologies used for hemp biomass were summarized in terms of sugar recoveries, lignin removal, and sugar and ethanol yields. This review presents numerous technical barriers attributed to insufficient fermentable sugar and ethanol …


Timing Of Deformation Along The Iron Springs Thrust, Southern Sevier Fold-And-Thrust Belt, Utah: Evidence For An Extensive Thrusting Event In The Mid-Cretaceous, J. Daniel Quick, John Patrick Hogan, Michael Wizevich, Jonathan Obrist-Farner, James L. Crowley Dec 2020

Timing Of Deformation Along The Iron Springs Thrust, Southern Sevier Fold-And-Thrust Belt, Utah: Evidence For An Extensive Thrusting Event In The Mid-Cretaceous, J. Daniel Quick, John Patrick Hogan, Michael Wizevich, Jonathan Obrist-Farner, James L. Crowley

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The temporal and spatial distribution of strain associated with the Sevier orogeny in western North America is significantly different in the southern end of the belt, at the latitude of Las Vegas, Nevada, than farther to the north at the latitude of Salt Lake City, Utah. Reasons for these differences have been speculative as a lack of temporal constraints on thrusting in the intervening region hindered along-strike correlation across the belt. We determined a crystallization age of 100.18 ± 0.04 Ma for zircons extracted from a recently recognized dacite lapilli ash-fall tuff near the base of the synorogenic Iron Springs …


Micro-Annulus Generation Under Downhole Conditions: Insights From Three-Dimensional Staged Finite Element Analysis Of Cement Hardening And Wellbore Operations, Weicheng Zhang, Andreas Eckert Dec 2020

Micro-Annulus Generation Under Downhole Conditions: Insights From Three-Dimensional Staged Finite Element Analysis Of Cement Hardening And Wellbore Operations, Weicheng Zhang, Andreas Eckert

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A micro-annulus (MA) is defined as a high permeability zone or gap initiating/occurring at the casing-cement and cement-formation interfaces during the wellbore life span. An MA can significantly compromise wellbore integrity by establishing enhanced fluid flow pathways. This study uses a staged finite element approach to simulate wellbore integrity during various loading steps of wellbore operations under downhole conditions. Particular emphasis is placed on the processes of cement poro-elastic property evolution, volume variation, and pore pressure variation as part of the cement hardening step. The resulting state of stress during the life cycle of a typical injection well (i.e. hardening, …


Impacts Of Environmental Conditions On Fleas In Black-Tailed Prairie Dog Burrows, Julia E. Poje, Tonie Rocke, Michael D. Samuel Dec 2020

Impacts Of Environmental Conditions On Fleas In Black-Tailed Prairie Dog Burrows, Julia E. Poje, Tonie Rocke, Michael D. Samuel

United States Geological Survey: Staff Publications

Sylvatic plague, caused by the bacterium Yersinia pestis and transmitted by fleas, occurs in prairie dogs of the western United States. Outbreaks can devastate prairie dog communities, often causing nearly 100% mortality. Three competent flea vectors, prairie dog specialists Oropsylla hirsuta and O. tuberculata, and generalist Pulex simulans, are found on prairie dogs and in their burrows. Fleas are affected by climate, which varies across the range of black-tailed prairie dogs (Cynomys ludovicianus), but these effects may be ameliorated somewhat due to the burrowing habits of prairie dogs. Our goal was to assess how temperature and precipitation …


Structure Analysis Of Natural Wangdaodeite—Linbo3-Type Fetio3, Oliver Tschauner, Chi Ma, Matthew G. Newville, Antonio Lanzirotti Dec 2020

Structure Analysis Of Natural Wangdaodeite—Linbo3-Type Fetio3, Oliver Tschauner, Chi Ma, Matthew G. Newville, Antonio Lanzirotti

Geoscience Faculty Research

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This paper reports the first structure refinement of natural wangdaodeite, LiNbO3-type FeTiO3 from the Ries impact structure. Wangdaodeite occurs together with recrystallized ilmenite clasts in shock melt veins which have experienced peak shock pressures of between 17 and 22 GPa. Comparison of natural and synthetic wangdaodeite points toward a correlation between the distortion of ferrate-and titanate-polyhedra and the c/a ratio of the unit cell. The Raman spectrum of wangdaodeite is calculated based on the refined structure. Comparison to the reported spectrum of the type-material shows that the Raman peak at 738–740 …


Monitoring 2019 Bonnet Carré Spillway Impacts - Final Report, J. Read Hendon, Jerry D. Wiggert, Jill Hendon Dec 2020

Monitoring 2019 Bonnet Carré Spillway Impacts - Final Report, J. Read Hendon, Jerry D. Wiggert, Jill Hendon

Faculty Publications

Due to the multiple and extended openings of the Bonnet Carré Spillway in 2019, the University of Southern Mississippi (USM) was tasked by the Mississippi Department of Marine Resources to conduct ecological sampling in the Mississippi Sound and adjacent waters. in an effort to better understand the impacts of the extensive freshwater diversion of Bonnet Carré Spillway operations on Mississippi's coastal and marine resources. The period of performance for this project was June 1, 2019, to August 31, 2019. This technical report summarizes the three months of weekly surveys and analyses, over June - August 2019, conducted by the University …


Population Demographics, Distribution, And Environmental History Of Asian Carp In A Great Plains River, Jake Werner Dec 2020

Population Demographics, Distribution, And Environmental History Of Asian Carp In A Great Plains River, Jake Werner

School of Natural Resources: Dissertations, Theses, and Student Research

Silver Carp Hypophthalmichthys molitrix, Bighead Carp H. nobilis, and Black Carp Mylopharyngodon piceus, collectively known as Asian carp, are a group of invasive fishes in the U.S.A. that have garnered much attention over the last couple decades. Most research devoted to this group of fishes has been focused in the Mississippi River basin with little investigation in the Missouri River drainage, particularly in tributary systems. The Kansas River is a major tributary to the Missouri River that has multiple anthropogenic barriers creating varying levels of connectivity within the Kansas River itself, and with the Missouri River. Information …


Compost And Biochar To Promote Soil Biological Activities Under Sweet Potatoes Cultivation In A Subtropical Semiarid Region, Josabeth Navarro, Jahdiel Salazar, James Jihoon Kang, Jason Parsons, Chu-Lin Cheng, Alexandria Castillo, Engil Isadora Pujol Pereira Nov 2020

Compost And Biochar To Promote Soil Biological Activities Under Sweet Potatoes Cultivation In A Subtropical Semiarid Region, Josabeth Navarro, Jahdiel Salazar, James Jihoon Kang, Jason Parsons, Chu-Lin Cheng, Alexandria Castillo, Engil Isadora Pujol Pereira

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

South Texas is located in a subtropical semiarid climate, and due to high temperature and irregular precipitation, farmers opt to leave their fields fallow during the summer months jeopardizing overall soil health. We evaluated whether sweet potato (Ipomoea batatas) cultivation coupled with drip irrigation could restore soil biological activities compared with bare fallow. Additionally, because sweet potatoes have high demand of soil nutrients, especially potassium (K), we evaluated the nutrient supply of locally sourced soil amendments. Sweet potato was cultivated during summer 2018 in McAllen, Texas, under control (no fertilizer), NPK (synthetic fertilizer), RC (yard-waste compost), and AC (compost produced …


Characterization Of Pathogen Airborne Inoculum Density By Information Theoretic Analysis Of Spore Trap Time Series Data, Robin A. Choudhury, Neil Mcroberts Nov 2020

Characterization Of Pathogen Airborne Inoculum Density By Information Theoretic Analysis Of Spore Trap Time Series Data, Robin A. Choudhury, Neil Mcroberts

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

In a previous study, air sampling using vortex air samplers combined with species-specific amplification of pathogen DNA was carried out over two years in four or five locations in the Salinas Valley of California. The resulting time series data for the abundance of pathogen DNA trapped per day displayed complex dynamics with features of both deterministic (chaotic) and stochastic uncertainty. Methods of nonlinear time series analysis developed for the reconstruction of low dimensional attractors provided new insights into the complexity of pathogen abundance data. In particular, the analyses suggested that the length of time series data that it is practical …


What Martian Meteorites Reveal About The Interior And Surface Of Mars, Arya Udry, G. H. Howarth, C. D.K. Herd, J. M.D. Day, T. J. Lapen, J. Filiberto Nov 2020

What Martian Meteorites Reveal About The Interior And Surface Of Mars, Arya Udry, G. H. Howarth, C. D.K. Herd, J. M.D. Day, T. J. Lapen, J. Filiberto

Geoscience Faculty Research

Martian meteorites are the only direct samples from Mars, thus far. Currently, there are a total of 262 individual samples originating from at least 11 ejection events. Geochemical analyses, through techniques that are also used on terrestrial rocks, provide fundamental insights into the bulk composition, differentiation and evolution, mantle heterogeneity, and role of secondary processes, such as aqueous alteration and shock, on Mars. Martian meteorites display a wide range in mineralogy and chemistry, but are predominantly basaltic in composition. Over the past 6 years, the number of martian meteorites recovered has almost doubled allowing for studies that evaluate these meteorites …


The Transition From Stochastic To Deterministic Bacterial Community Assembly During Permafrost Thaw Succession, Stacey J. Doherty, Robyn A. Barbato, A. Stuart Grandy, W. Kelley Thomas, Sylvain Monteux, Ellen Dorrepaal, Margareta Johansson, Jessica G. Ernakovich Nov 2020

The Transition From Stochastic To Deterministic Bacterial Community Assembly During Permafrost Thaw Succession, Stacey J. Doherty, Robyn A. Barbato, A. Stuart Grandy, W. Kelley Thomas, Sylvain Monteux, Ellen Dorrepaal, Margareta Johansson, Jessica G. Ernakovich

Faculty Publications

The Northern high latitudes are warming twice as fast as the global average, and permafrost has become vulnerable to thaw. Changes to the environment during thaw leads to shifts in microbial communities and their associated functions, such as greenhouse gas emissions. Understanding the ecological processes that structure the identity and abundance (i.e., assembly) of pre- and post-thaw communities may improve predictions of the functional outcomes of permafrost thaw. We characterized microbial community assembly during permafrost thaw using in situ observations and a laboratory incubation of soils from the Storflaket Mire in Abisko, Sweden, where permafrost thaw has occurred over the …


The Dynamics Of Nonlinear Atmospheric Acoustic-Gravity Waves Generated By Tsunamis Over Realistic Bathymetry, P. A. Inchin, C. J. Heale, J. B. Snively, M. D. Zettergren Nov 2020

The Dynamics Of Nonlinear Atmospheric Acoustic-Gravity Waves Generated By Tsunamis Over Realistic Bathymetry, P. A. Inchin, C. J. Heale, J. B. Snively, M. D. Zettergren

Publications

The investigation of atmospheric tsunamigenic acoustic and gravity wave (TAGW) dynamics, from the ocean surface to the thermosphere, is performed through the numerical computations of the 3D compressible nonlinear Navier-Stokes equations. Tsunami propagation is first simulated using a nonlinear shallow water model, which incorporates instantaneous or temporal evolutions of initial tsunami distributions (ITD). Ocean surface dynamics are then imposed as a boundary condition to excite TAGWs into the atmosphere from the ground level. We perform a case study of a large tsunami associated with the 2011 M9.1 Tohuku-Oki earthquake and parametric studies with simplified and demonstrative bathymetry and ITD. Our …


Sea Level Rise Impact Assessment Tool – A Web-Based Application For Community Resilience In Coral Gables, Florida, Levente Juhasz, Hartwig H. Hochmair, Sheyla Aguilar De Santana, Zhaohui J. Fu Nov 2020

Sea Level Rise Impact Assessment Tool – A Web-Based Application For Community Resilience In Coral Gables, Florida, Levente Juhasz, Hartwig H. Hochmair, Sheyla Aguilar De Santana, Zhaohui J. Fu

GIS Center

No abstract provided.


Evidence Of Nickel And Other Trace Elements And Their Relationship To Clinical Findings In Acute Mesoamerican Nephropathy: A Case-Control Analysis, Rebecca S. B. Fischer, Jason M. Unrine, Chandan Vangala, Wayne T. Sanderson, Sreedhar Mandayam, Kristy O. Murray Nov 2020

Evidence Of Nickel And Other Trace Elements And Their Relationship To Clinical Findings In Acute Mesoamerican Nephropathy: A Case-Control Analysis, Rebecca S. B. Fischer, Jason M. Unrine, Chandan Vangala, Wayne T. Sanderson, Sreedhar Mandayam, Kristy O. Murray

Plant and Soil Sciences Faculty Publications

BACKGROUND: Although there are several hypothesized etiologies of Mesoamerican Nephropathy (MeN), evidence has not yet pointed to the underlying cause. Exposure to various trace elements can cause the clinical features observed in MeN.

METHODS AND FINDINGS: We measured 15 trace elements, including heavy metals, in renal case-patients (n = 18) and healthy controls (n = 36) in a MeN high-risk region of Nicaragua. Toenails clippings from study participants were analyzed using inductively coupled plasma mass spectrometry. A case-control analysis was performed, and concentrations were also analyzed over participant characteristics and clinical parameters. Nickel (Ni) concentrations were significantly higher in toenails …


Connections In The Underworld: A Morphological And Molecular Study Of Diversity And Connectivity Among Anchialine Shrimp., Robert Eugene Ditter Nov 2020

Connections In The Underworld: A Morphological And Molecular Study Of Diversity And Connectivity Among Anchialine Shrimp., Robert Eugene Ditter

FIU Electronic Theses and Dissertations

This research investigates the distribution and population structure of crustaceans, endemic to anchialine systems in the tropical western Atlantic focusing on cave-dwelling shrimp from the family Barbouriidae. Taxonomic and molecular tools (genetic and genomic) are utilized to examine population dynamics and the presence of phenotypic hypervariation (PhyV) of the critically endangered species Barbouria cubensis (von Martens, 1872). The presence of PhyV and its geographic distribution is investigated among anchialine populations of B. cubensis from 34 sites on Abaco, Eleuthera, and San Salvador, Bahamas. Examination of 54 informative morphological characters revealed PhyV present in nearly 90% (n=463) of specimens with no …


Aspergillus Niger Decreases Bioavailability Of Arsenic(V) Via Biotransformation Of Manganese Oxide Into Biogenic Oxalate Minerals, Bence Farkas, Marek Kolenčík, Miroslav Hain, Edmund Dobročka, Gabriela Kratošová, Marek Bujdoš, Huan Feng, Yang Deng, Qian Yu, Ramakanth Illa, B. Ratna Sunil, Hyunjung Kim, Peter Matúš, Martin Urík Nov 2020

Aspergillus Niger Decreases Bioavailability Of Arsenic(V) Via Biotransformation Of Manganese Oxide Into Biogenic Oxalate Minerals, Bence Farkas, Marek Kolenčík, Miroslav Hain, Edmund Dobročka, Gabriela Kratošová, Marek Bujdoš, Huan Feng, Yang Deng, Qian Yu, Ramakanth Illa, B. Ratna Sunil, Hyunjung Kim, Peter Matúš, Martin Urík

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The aim of this work was to evaluate the transformation of manganese oxide (hausmannite) by microscopic filamentous fungus Aspergillus niger and the effects of the transformation on mobility and bioavailability of arsenic. Our results showed that the A. niger strain CBS 140837 greatly affected the stability of hausmannite and induced its transformation into biogenic crystals of manganese oxalates—falottaite and lindbergite. The transformation was enabled by fungal acidolysis of hausmannite and subsequent release of manganese ions into the culture medium. While almost 45% of manganese was bioextracted, the arsenic content in manganese precipitates increased throughout the 25-day static cultivation of fungus. …


Modeling Holocene Peatland Carbon Accumulation In North America, Qianlai Zhuang, Sirui Wang, Bailu Zhao, Filipe Aires, Catherine Prigent, Zicheng Yu, Jason K. Keller, Scott Bridgham Nov 2020

Modeling Holocene Peatland Carbon Accumulation In North America, Qianlai Zhuang, Sirui Wang, Bailu Zhao, Filipe Aires, Catherine Prigent, Zicheng Yu, Jason K. Keller, Scott Bridgham

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Peatlands are a large carbon reservoir. Yet the quantification of their carbon stock still has a large uncertainty due to lacking observational data and well‐tested peatland biogeochemistry models. Here, a process‐based peatland model was calibrated using long‐term peat carbon accumulation data at multiple sites in North America. The model was then applied to quantify the peat carbon accumulation rates and stocks within North America over the last 12,000 years. We estimated that 85–174 Pg carbon was accumulated in North American peatlands over the study period including 0.37–0.76 Pg carbon in subtropical peatlands. During the period from 10,000 to 8,000 years …


Fungal Community Structure And Function Shifts With Atmospheric Nitrogen Deposition, Jessica A. M. Moore, Mark A. Anthony, Gregory J. Pec, Lidia K. Trocha, Artur Trzebny, Kevin M. Geyer, Linda T. A. Van Diepen, Serita D. Frey Nov 2020

Fungal Community Structure And Function Shifts With Atmospheric Nitrogen Deposition, Jessica A. M. Moore, Mark A. Anthony, Gregory J. Pec, Lidia K. Trocha, Artur Trzebny, Kevin M. Geyer, Linda T. A. Van Diepen, Serita D. Frey

Faculty Publications

Fungal decomposition of soil organic matter depends on soil nitrogen (N) availability. This ecosystem process is being jeopardized by changes in N inputs that have resulted from a tripling of atmospheric N deposition in the last century. Soil fungi are impacted by atmospheric N deposition due to higher N availability, as soils are acidified, or as micronutrients become increasingly limiting. Fungal communities that persist with chronic N deposition may be enriched with traits that enable them to tolerate environmental stress, which may trade-off with traits enabling organic matter decomposition. We hypothesized that fungal communities would respond to N deposition by …


Mass And Number Size Distributions Of Rbc In Snow And Firn Samples From Pine Island Glacier, West Antarctica, Luciano Marquetto, Susan Kaspari, Jefferson Cardia Simões Nov 2020

Mass And Number Size Distributions Of Rbc In Snow And Firn Samples From Pine Island Glacier, West Antarctica, Luciano Marquetto, Susan Kaspari, Jefferson Cardia Simões

Geological Sciences Faculty Scholarship

An extended‐range Single Particle Soot Photometer (SP2) coupled to a Marin‐5 nebulizer was used to measure the refractory black carbon (rBC) mass and number size distributions in 1,004 samples from a West Antarctica snow/firn core. The SP2 was calibrated using Aquadag and a Centrifugal Particle Mass Analyzer for BC particles ranging from 0.5 to 800 fg. Our results indicate a significant contribution of rare, large particles of mass‐equivalent diameter (DBC) > 500 nm to the total rBC mass (36%), while small particles (DBC < 100 nm) are abundant but contribute <8% to total rBC mass. We observed a primary mass median diameter of 162 ± 40 nm, smaller than reported for snow in other regions of the globe but similar to East Antarctica rBC size distributions. In addition, we observed other modes at 673, 1,040, and >1,810 nm (uncontained mode). We compared two sets of samples from different seasons …