Digital Commons Network^™

Cognitively Normal Women With Alzheimer’S Disease Proteinopathy Show Relative Preservation Of Memory But Not Of Hippocampal Volume, Jessica Z.K. Caldwell, Jeffrey L. Cummings, Sarah J. Banks, Sebastian Palmqvist, Oskar Hansson

School of Medicine Faculty Publications

Background: We examined interactive effects of sex, diagnosis, and cerebrospinal fluid (CSF) amyloid beta/phosphorylated tau ratio (Aβ/P-tau) on verbal memory and hippocampal volumes. Methods: We assessed 682 participants (350 women) from BioFINDER (250 cognitively normal [CN]; and 432 symptomatic: 186 subjective cognitive decline [SCD], 246 mild cognitive impairment [MCI]). General linear models evaluated effects of Alzheimer’s disease (AD) proteinopathy (CSF Aß/p-tau ratio), diagnosis, and sex on verbal memory (ADAS-cog 10-word recall), semantic fluency (animal naming fluency), visuospatial skills (cube copy), processing speed/attention functions (Symbol Digit Modalities Test and Trail Making Part A), and hippocampal volumes. Results: Amyloid-positive (Aβ/P-tau+) CN women …

Robust Cullin-Ring Ligase Function Is Established By A Multiplicity Of Poly-Ubiquitylation Pathways, Spencer Hill, Kurt Reichermeier, Daniel C. Scott, Lorena Samentar, Jasmin Coulombe-Huntington, Luisa Izzi, Xiaojing Tang, Rebeca Ibarra, Thierry Bertomeu, Annie Moridian, Michael J. Sweredoski, Nora Caberoy, Brenda A. Schulman, Frank Sicheri, Mike Tyers, Gary Kleiger

Life Sciences Faculty Research

The cullin-RING ligases (CRLs) form the major family of E3 ubiquitin ligases. The prototypic CRLs in yeast, called SCF enzymes, employ a single E2 enzyme, Cdc34, to build poly-ubiquitin chains required for degradation. In contrast, six different human E2 and E3 enzyme activities, including Cdc34 orthologs UBE2R1 and UBE2R2, appear to mediate SCF-catalyzed substrate polyubiquitylation in vitro. The combinatorial interplay of these enzymes raises questions about genetic buffering of SCFs in human cells and challenges the dogma that E3s alone determine substrate specificity. To enable the quantitative comparisons of SCF-dependent ubiquitylation reactions with physiological enzyme concentrations, mass spectrometry was employed …

Isolation Of Metrosideros (`Ohi`A) Taxa On O`Ahu Increases With Elevation And Extreme Environments, Elizabeth A. Stacy, Tomoko Sakishima, Heaven Tharp, Neil Snow

Life Sciences Faculty Research

Species radiations should be facilitated by short generation times and limited dispersal among discontinuous populations. Hawaii’s hyper-diverse, landscape-dominant tree, Metrosideros, is unique among the islands’ radiations for its massive populations that occur continuously over space and time within islands, its exceptional capacity for gene flow by both pollen and seed, and its extended life span (ca. >650 years). Metrosideros shows the greatest phenotypic and microsatellite DNA diversity on O`ahu, where taxa occur in tight sympatry or parapatry in mesic and montane wet forest on 2 volcanoes. We document the nonrandom distributions of 12 taxa (including unnamed morphotypes) along elevation gradients, …

Restructuring Of The Axon Initial Segment In Mouse Models Of Neurodevelopmental Disorders, Rachel Ali Rodriguez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Neurodevelopmental disorders (NDDs) affect more than 36% of children in countries with low- and middle- incomes (Boivin, 2015; McCoy, 2016). Interestingly, these heterogeneous disorders share a high incidence of epileptic seizures, suggesting a shared pathology. Seizures result when neuronal firing activity becomes disturbed and neurons fire excessively or in unregulated patterns. A key site in the control of neuronal firing patterns is the axon initial segment (AIS), where the local density of proteins and the morphology of the AIS in part determine the firing of neurons. We hypothesized that a disruption in the morphology and/or composition of the AIS can …

Landscape Scale: Inter- And Intraspecific Variation In Plant Interactions Along A Stress Gradient In The Sheep Range Of Nevada, Jordan Dowell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Impending threats to shrubland ecosystems, posed by climate change, necessitate niche modeling efforts to project vegetation range shifts. However, efforts often remain unguided by individual-scale interspecific plant interactions. The stress gradient hypothesis posits that facilitation should increase in areas of high abiotic stress, only if the individuals are able to ameliorate the surrounding area via functional traits. The Sheep Range of Nevada was used to assess the role of functional traits as predictors of plant association. Larrea tridentata, Coleogyne ramosissima, and Artemisia nova were selected as shrubs with variable life history strategies and ranges in order to identify general patterns …

The Effect Of Pleistocene Glacial - Interglacial Cycles On Patterns Of Genetic Diversity And Differentiation Of Populations Of Leptodactylus Albilabris (White-Lipped Frog) In The Puerto Rican Bank, Andre Nguyen

UNLV Theses, Dissertations, Professional Papers, and Capstones

The historical distributional shifts of various species have been attributed to the glacial-interglacial cycles of the Pleistocene Epoch (2.6 mya – 10,000 ya). Sea level changes caused by Pleistocene glacial-interglacial cycles impacted the total area of landmasses, particularly in island systems. Cooler, glacial periods increased emergent (subaerial) island area via lower sea levels. Adjacent islands may have become connected through emergent land bridges, resulting in a larger subaerial landmass. Warmer interglacial periods led to higher sea levels, which in turn reduced island area, and in some cases, submerged land bridges, fragmenting larger islands into separate, smaller units. The Puerto Rican …

The Perplexing Paradox Of Clostridioides (Clostridium) Difficile Infection (Cdi) - Analysis Of Anti-Germinants As Part Of Cdi Prophylaxis, Christopher Yip

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clostridioides (Clostridium) difficile infections (CDI) have become the leading cause of nosocomial antibiotic-associated diarrhea worldwide. Under normal circumstances, bacteria found in the gastrointestinal tract provide a barrier against C. difficile colonization. Upon antibiotic therapy, the protective barrier is lost as the microbial community becomes depleted thus providing the opportunity for C. difficile to colonize the human gut. Exposure to taurocholate, a bile acid produced within the mammalian gastrointestinal tract, causes C. difficile spores to begin their transition, a process known as germination, from metabolically dormant structures to toxin-producing cells. As germination is required for the onset of CDI, anti-germination compounds …

Trade-Offs Between Survival And Reproduction In Starvation-Selected Drosophila Melanogaster, Tammara Beeghly

UNLV Theses, Dissertations, Professional Papers, and Capstones

Evolutionary outcomes are demonstrated by traits that affect an organism’s schedule of reproduction and survival. These life history traits are reflected in an organism’s physiology, development and behavior. Environmental changes, such as availability of nutritional resources, can profoundly affect evolutionary outcomes of individuals and populations. When shortages arise, there will be trade-offs in the allocation of resources, where one trait prevails at the expense of another.

In the laboratory, we can mimic conditions in nature and study the specific effects of the conditions that we re-create. In our case, over 100 generations of Drosophila melanogaster have been selected for starvation …

Discovering Motor Phenotypes In Autism Spectrum Disorder: A Cross-Syndrome Approach, Daniel Edwin Lidstone

UNLV Theses, Dissertations, Professional Papers, and Capstones

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder with a behavioral phenotype characterized by persistent deficits in social communication and social interaction accompanied by restricted, repetitive patterns of behaviors, interests, or activities. Currently in the US, approximately 2.5% of children have a diagnosis of ASD. The etiology of ASD is complex, however the disorder does have a strong genetic basis. Specific genetic mutations can lead to neuroanatomical and neurophysiological changes during development resulting in a behavioral phenotype that falls along the ASD spectrum and may result in a diagnosis of ASD. The severity of ASD-specific behaviors falls on a continuum …

Mojave Desert Ecosystem Recovery: Potency Of Biotic And Abiotic Restoration Methods In Low Elevation Plant Communities, Mary Amanda Balogh

UNLV Theses, Dissertations, Professional Papers, and Capstones

The historic and current state of land in the Mojave Desert, including land managed by the National Park Service with fundamental goals of natural resource conservation and preservation, been severely degraded by a variety of anthropogenic disturbances. Due to increasingly sporadic and unpredictable precipitation patterns, land managers struggle to implement restoration projects with high success rates and are resource-limited for post-treatment monitoring. In this study, I examined success rates of biotic (outplanting, seeding) and abiotic (soil manipulation, vertical mulch) restoration treatments on various disturbance types in the creosote-bursage (Larrea tridentata-Ambrosia dumosa), blackbrush (Coleogyne ramosissima), and Joshua tree woodland (Yucca brevifolia) …

Mojave Desert Plant Community Long-Term Response To Disturbance, Dominic M. Gentilcore

UNLV Theses, Dissertations, Professional Papers, and Capstones

All vegetation communities have been shaped by disturbances. This dissertation consists of three separate chapters: Blackbrush (Coleogyne ramosissima) natural regeneration in the Great Basin-Mojave Desert Transition Zone on two fires, Long-term Response to Fire in Eastern Mojave Desert semi-arid shrubland communities, and an Annotated Checklist of Gold Butte National Monument in the Mojave-Colorado Plateau Transition Zone. The section on blackbrush natural regeneration was a long-term dataset from two fires in Basin and Range National Monument that burned in 2008 with monitoring events in 2009, 2010, 2011, 2018 and 2019. The monitoring documented some of the strongest post-fire regeneration for the …

Uncovering New Mechanisms Of Cdc34 And Cullin-Ring Activity, Spencer Hill

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ubiquitylation is a cellular regulatory system found in all eukaryotic cells, which has managed to find a role in most pathways imaginable. The system works fundamentally through the ligation of a small protein known as ubiquitin onto a substrate. Depending on the context of the ubiquitin ligation, the substrate can be directed towards a number of cellular fates, the best-studied being degradation of the substrate. While originally thought of as a signal for cellular disposal units to degrade aberrant proteins, we now know that ubiquitin plays a highly nuanced role in cellular epistasis, controlling everything from the cell cycle to …

Tunnel-Tube And Fourier Methods For Measuring Three-Dimensional Medium Reaction Force In Burrowing Animals, Alexis Moore Crisp, Clinton J. Barnes, David V. Lee

Life Sciences Faculty Research

Subterranean digging behaviors provide opportunities for protection, access to prey, and predator avoidance for a diverse array of vertebrates, yet studies of the biomechanics of burrowing have been limited by the technical challenges of measuring kinetics and kinematics of animals moving within a medium. We describe a new system for measuring 3D reaction forces during burrowing, called a ‘tunnel-tube’, which is composed of two, separately instrumented plastic tubes: an ‘entry tube’ with no medium, in series with a ‘digging tube’ filled with medium. Mean reaction forces are measured for a digging bout and Fourier analysis is used to quantify the …

Local‐Regional Similarity In Drylands Increases During Multiyear Wet And Dry Periods And In Response To Extreme Events, Matthew D. Petrie, D. P.C. Peters, N. D. Bruss, W. Ji, H. M. Savoy

Life Sciences Faculty Research

Climate change is predicted to impact ecosystems through altered precipitation (PPT) regimes. In the Chihuahuan Desert, multiyear wet and dry periods and extreme PPT pulses are the most influential climatic events for vegetation. Vegetation responses are most frequently studied locally, and regional responses are often unclear. We present an approach to quantify correlation of PPT and vegetation responses (as Normalized Difference Vegetation Index [NDVI]) at the Jornada ARS‐LTER site (JRN; 550 km2 area) and the surrounding dryland region (from 0 to 500 km distance; 400,000 km2 study area) as a way to understand regional similarity to locally observed patterns. We …

Relation Between Relative Handgrip Strength, Chronological Age And Physiological Age With Lower Functional Capacity In Older Women, Wylker Souza Saraiva, Jonato Prestes, Silvana Schwerz Funghetto, James Wilfred Navalta, Ramires Alsamir Tibana, Dahan Da Cunha Nascimento

Integrated Health Sciences Faculty Publications

Purpose: Relative handgrip strength (RHGS), Aged Based on Exercise Stress Testing (A-BEST), and chronological age were evaluated as predictors of impaired mobility in older women. Methods: Participants included 88 older women (mean age 68.13±6.02 years) referred for exercise stress testing. Estimated physiological age was computed based on exercise capacity, chronotropic reserve index, heart rate recovery, and medication that could affect heart rate. RHGS was measured using a validated handgrip hydraulic dynamometer and mobility was evaluated by timed up and go test (TUG-test). A hierarchical multiple regression predicted TUG-test performance from A-BEST, chronological age and RHGS. Results: After adjustment for diabetes, …

Biological And Practical Implications Of Genome-Wide Association Study Of Schizophrenia Using Bayesian Variable Selection, Benazir Rowe, Xiangning Chen, Zuoheng Wang, Jingchun Chen, Amei Amei

School of Medicine Faculty Publications

Genome-wide association studies (GWAS) have identified over 100 loci associated with schizophrenia. Most of these studies test genetic variants for association one at a time. In this study, we performed GWAS of the molecular genetics of schizophrenia (MGS) dataset with 5334 subjects using multivariate Bayesian variable selection (BVS) method Posterior Inference via Model Averaging and Subset Selection (piMASS) and compared our results with the previous univariate analysis of the MGS dataset. We showed that piMASS can improve the power of detecting schizophrenia-associated SNPs, potentially leading to new discoveries from existing data without increasing the sample size. We tested SNPs in …

International Society Of Sports Nutrition Position Stand: Nutritional Considerations For Single-Stage Ultra-Marathon Training And Racing, Nicholas B. Tiller, Justin D. Roberts, Liam Beasley, Shaun Chapman, Jorge M. Pinto, Lee Smith, Melanie Wiffin, Mark Russel, S. Andy Sparks, Lauren Duckworth, John O'Hara, Louise Sutton, Jose Antonio, Darryn S. Willoughby, Michael D. Tarpey, Abbie E. Smith-Ryan, Michael J. Ormsbee, Todd A. Astorino, Richard B. Kreider, Graham R. Mcginnis, Jeffrey R, Stout, Johneric W. Smith, Shawn M. Arent, Bill I. Campbell, Laurent Bannock

Kinesiology and Nutrition Sciences Faculty Publications

In this Position Statement, the International Society of Sports Nutrition (ISSN) provides an objective and critical review of the literature pertinent to nutritional considerations for training and racing in single-stage ultra-marathon. Recommendations for Training. i) Ultra-marathon runners should aim to meet the caloric demands of training by following an individualized and periodized strategy, comprising a varied, food-first approach; ii) Athletes should plan and implement their nutrition strategy with sufficient time to permit adaptations that enhance fat oxidative capacity; iii) The evidence overwhelmingly supports the inclusion of a moderate-to-high carbohydrate diet (i.e., ~ 60% of energy intake, 5–8 g·kg− 1·d− 1) …

Phytoplankton Community And Algal Toxicity At A Recurring Bloom In Sullivan Bay, Kabetogama Lake, Minnesota, Usa, Victoria G. Christensen, Ryan P. Maki, Erin A. Stelzer, Jack E. Norlan, Eakalak Khan

Civil and Environmental Engineering and Construction Faculty Research

Kabetogama Lake in Voyageurs National Park, Minnesota, USA suffers from recurring late summer algal blooms that often contain toxin-producing cyanobacteria. Previous research identified the toxin microcystin in blooms, but we wanted to better understand how the algal and cyanobacterial community changed throughout an open water season and how changes in community structure were related to toxin production. Therefore, we sampled one recurring bloom location throughout the entire open water season. The uniqueness of this study is the absence of urban and agricultural nutrient sources, the remote location, and the collection of samples before any visible blooms were present. Through quantitative …

Divergent Selection And Primary Gene Flow Shape Incipient Speciation Of A Riparian Tree On Hawaii Island, Jae Young Choi, Michael Purugganan, Elizabeth A. Stacy

Life Sciences Faculty Research

A long-standing goal of evolutionary biology is to understand the mechanisms underlying the formation of species. Of particular interest is whether or not speciation can occur in the presence of gene flow and without a period of physical isolation. Here, we investigated this process within Hawaiian Metrosideros, a hypervariable and highly dispersible woody species complex that dominates the Hawaiian Islands in continuous stands. Specifically, we investigated the origin of Metrosideros polymorpha var. newellii (newellii), a riparian ecotype endemic to Hawaii Island that is purportedly derived from the archipelago-wide M. polymorpha var. glaberrima (glaberrima). Disruptive selection across a sharp forestriparian ecotone …

Magnetosome Gene Duplication As An Important Driver In The Evolution Of Magnetotaxis In The Alphaproteobacteria, Haijian Du, Wenyan Zhang, Wensi Zhang, Weijia Zhang, Hongmiao Pan, Yongxin Pan, Dennis A. Bazylinski, Long-Fei Wu, Tian Xiao, Wei Lin

Life Sciences Faculty Research

The evolution of microbial magnetoreception (or magnetotaxis) is of great interest in the fields of microbiology, evolutionary biology, biophysics, geomicrobiology, and geochemistry. Current genomic data from magnetotactic bacteria (MTB), the only prokaryotes known to be capable of sensing the Earth’s geomagnetic field, suggests an ancient origin of magnetotaxis in the domain Bacteria. Vertical inheritance, followed by multiple independent magnetosome gene cluster loss, is considered to be one of the major forces that drove the evolution of magnetotaxis at or above the class or phylum level, although the evolutionary trajectories at lower taxonomic ranks (e.g., within the class level) remain largely …

Patient And Provider Perspectives On How Trust Influences Maternal Vaccine Acceptance Among Pregnant Women In Kenya, Stacy W. Nganga, Nancy A. Otieno, Maxwell Adero, Dominic Ouma, Sandra S. Chaves, Jennifer R. Verani, Marc-Alain Widdowson, Andrew Wilson, Irina Bergenfeld, Courtni Andrews, Vincent L. Fenimore, Ines Gonzalez-Casanova, Paula M. Frew, Saad B. Omer, Fauzia A. Malik

Environmental & Occupational Health Faculty Publications

Background Pregnant women and newborns are at high risk for infectious diseases. Altered immunity status during pregnancy and challenges fully vaccinating newborns contribute to this medical reality. Maternal immunization is a strategy to protect pregnant women and their newborns. This study aimed to find out how patient-provider relationships affect maternal vaccine uptake, particularly in the context of a lower middle- income country where limited research in this area exists. Methods We conducted semi-structured, in-depth narrative interviews of both providers and pregnant women from four sites in Kenya: Siaya, Nairobi, Mombasa, and Marsabit. Interviews were conducted in either English or one …

Identifiying High Risk Areas Of Zika Virus Infection By Meteorological Factors In Columbia, Lung-Chang Chien, Francisco Sy, Adriana Perez

Environmental & Occupational Health Faculty Publications

Background Several Zika virus (ZIKV) outbreaks have occurred since October 2015. Because there is no effective treatment for ZIKV infection, developing an effective surveillance and warning system is currently a high priority to prevent ZIKV infection. Despite Aedes mosquitos having been known to spread ZIKV, the calculation approach is diverse, and only applied to local areas. This study used meteorological measurements to monitor ZIKV infection due to the high correlation between climate change and Aedes mosquitos and the convenience to obtain meteorological data from weather monitoring stations. Methods This study applied the Bayesian structured additive regression modeling approach to include …

Testing Protocols For Surveying Captive Limulus Polyphemus Microbiomes, Fabian Leija, Sean A. Neiswenter Dr.

LSAMP Poster Presentations

Limulus polyphemus, the Atlantic horseshoe crab, is a marine arthropod that primarily resides in the shallow intertidal zone of brackish water, water where high salinity seawater meets fresh water. The ecological niche that horseshoe crabs reside in makes them an ideal animal to be placed in an aquarium touch-tank, only needing a shallow pool of water to live comfortably as well as having a tough chitin carapace that won’t be easily damaged by visitors touching them. However, the implications of these human-animal interactions are severely unexplored with limited research being conducted regarding touch-tanks. In contrast, the consequences and hygienic practices …

Adsorption Of Methylene Blue And In-Situ Reactivation Of Granular Activated Carbon (Gac) With Ozone, Christina Obra, Tran Xuan Vu, Meena Ejjada, George William Kajjumba, Erica J. Marti

LSAMP Poster Presentations

Granular activated carbon (GAC) is a porous, fine-grained adsorbent rich in carbon and it has been widely applied in water and wastewater treatment processes. For instance, GAC can be utilized in adsorption processes. Adsorption is a purification technique in which soluble impurities are removed from the solvent and adhere to the surface and pores of a solid material. Ozonation is extensively used in the treatment of wastewater as well. (Turhan, Durukan, Ozturkcan, & Turgut, 2012). Because of its high oxidizing power, ozone can break down colored substances like dyes in wastewater, which improves the aesthetics of water. However, to treat …

Archaeological Analysis In The Information Age: Guidelines For Maximizing The Reach, Comprehensiveness, And Longevity Of Data, Sarah W. Kansa, Levent Atici, Eric C. Kansa, Richard H. Meadow

Anthropology Faculty Research

With the advent of the Web, increased emphasis on “research data management,” and innovations in reproducible research practices, scholars have more incentives and opportunities to document and disseminate their primary data. This article seeks to guide archaeologists in data sharing by highlighting recurring challenges in reusing archived data gleaned from observations on workflows and reanalysis efforts involving datasets published over the past 15 years by Open Context. Based on our findings, we propose specific guidelines to improve data management, documentation, and publishing practices so that primary data can be more efficiently discovered, understood, aggregated, and synthesized by wider research communities.

Correction To: Transcriptome Analyses Of Tumor-Adjacent Somatic Tissues Reveal Genes Co-Expressed With Transposable Elements, Micky Chung, G. M. Jonaid, Sophia Quinton, Austin Ross, Corinne E. Sexton, Adrian Alberto, Cody Clymer, Daphnie Churchill, Omar Navarro Leija, Mira V. Han

Life Sciences Faculty Research

Following publication of the original article [1], the authors reported errors in Table 2 wherein all “KZFP” in the gene names should be changed to “ZNF”.

Effects Of Rate Of Drying, Life History Phase, And Ecotype On The Ability Of The Moss Bryum Argenteum To Survive Desiccation Events And The Influence On Conservation And Selection Of Material For Restoration, Joshua Lee Greenwood, Lloyd R. Stark, Lindsay P. Chiquoine

Life Sciences Faculty Research

Desiccation stress is frequently experienced by the moss Bryum argenteum and can influence survival, propagation and niche selection. We attempted to disentangle the interacting factors of life history phase (five categories) and rate of desiccation (time allotted for induction of desiccation tolerance) for 13 ecotypes of B. argenteum. Using chlorophyll fluorescence as a stress index, we determined how these parameters influenced desiccation tolerance. Rate of drying and life phase significantly affected desiccation tolerance. The reaction norms of desiccation tolerance displayed by the 13 ecotypes showed a substantial degree of variation in phenotypic plasticity. We observed differences in survival and fluorescence …

Changes In Pm2.5 Peat Combustion Source Profiles With Atmospheric Aging In An Oxidation Flow Reactor, Judith C. Chow, Junji Cao, Lung-Wen Anthony Chen, Xiaoliang Wang, Qiyuan Wang, Jie Tian, Steven Sai Hang Ho, Adam C. Watts, Tessa B. Carlson, Steven D. Kohl, John G. Watson

Environmental & Occupational Health Faculty Publications

Smoke from laboratory chamber burning of peat fuels from Russia, Siberia, the USA (Alaska and Florida), and Malaysia representing boreal, temperate, subtropical, and tropical regions was sampled before and after passing through a potential-aerosol-mass oxidation flow reactor (PAM-OFR) to simulate intermediately aged (∼2 d) and well-aged (∼7 d) source profiles. Species abundances in PM2.5 between aged and fresh profiles varied by several orders of magnitude with two distinguishable clusters, centered around 0.1 % for reactive and ionic species and centered around 10 % for carbon. Organic carbon (OC) accounted for 58 %–85 % of PM2.5 mass in fresh profiles with …

A Dynamic Quantitative Microbial Risk Assessment For Norovirus In Potable Reuse System, Erfaneh Amoueyan, Sajjad Ahmad, Joseph N.S. Eisenberg, Daniel Gerrity

Civil and Environmental Engineering and Construction Faculty Research

This study describes the results of a dynamic quantitative microbial risk assessment (QMRA) for norovirus (NoV) that was used to evaluate the relative significance of foodborne, person-to-person, and person-to-sewage-to-person transmission pathways. This last pathway was incorporated into simulated potable reuse systems to evaluate the adequacy of typical treatment trains, operational conditions, and regulatory frameworks. The results confirm that secondary and foodborne transmission dominate the overall risk calculation and that waterborne NoV likely contributes no appreciable public health risk, at least in the scenarios modeled in this study. De facto reuse with an environmental buffer storage time of at least 30 …

Insights Into The Ecological Roles And Evolution Of Methyl-Coenzyme M Reductase-Containing Hot Spring Archaea, Zheng-Shuang Hua, Yu-Lin Wang, Paul N. Evans, Yan-Ni Qu, Kian Mau Goh, Yang-Zhi Rao, Sun Yat-Sen University Qi, Yu-Xian Li, Min-Jun Huang, Jian-Yu Jiao, Ya-Ting Chen, Wen-Sheng Shu, Wael Hozzein, Brian P. Hedlund, Gene W. Tyson, Tong Zhang, Wen-Jun Li

Life Sciences Faculty Research

Several recent studies have shown the presence of genes for the key enzyme associated with archaeal methane/alkane metabolism, methyl-coenzyme M reductase (Mcr), in metagenome-assembled genomes (MAGs) divergent to existing archaeal lineages. Here, we study the mcr-containing archaeal MAGs from several hot springs, which reveal further expansion in the diversity of archaeal organisms performing methane/alkane metabolism. Significantly, an MAG basal to organisms from the phylum Thaumarchaeota that contains mcr genes, but not those for ammonia oxidation or aerobic metabolism, is identified. Together, our phylogenetic analyses and ancestral state reconstructions suggest a mostly vertical evolution of mcrABG genes among methanogens and methanotrophs, …