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2019

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The Roles Of Absorption In Music Therapy, Michael John Russo Jan 2019

The Roles Of Absorption In Music Therapy, Michael John Russo

Theses & Dissertations

Absorption refers to the phenomenon of total attentional engagement. The purpose of the current study was to gain a preliminary understanding of the roles that absorption may have in different music therapy approaches. The research questions were: a) How might music therapists know when their clients are in states of absorption?, b) How might absorption influence the ability of music therapy clients to progress towards therapeutic goals?, and c) What is the potential relationship between absorption and music? Three music therapists with self-identified expertise and experience in conceptualizing absorption in music therapy were interviewed about their observations and opinions of …


Vcu Campus Tree Plan, Bilal Damaj Jan 2019

Vcu Campus Tree Plan, Bilal Damaj

Master of Urban and Regional Planning Capstone Projects

Throughout the past several years VCU has grown tremendously as a large public research university and an anchor institution within the city of Richmond However, VCU also has been working towards a more sustainable future and is committed to furthering sustainability in its community and campuses. While VCU has several long-range plans dedicated towards different aspects of the University’s planning and design initiatives, the University does not have any plan dedicated specifically towards its campus trees or tree canopy. An analysis of the existing conditions on VCU’s campuses found that there is low amount of urban tree canopy cover, high …


Perspectives On Teaching The Family Communication Course, Tiffany R. Wang, Jeffrey T. Child Jan 2019

Perspectives On Teaching The Family Communication Course, Tiffany R. Wang, Jeffrey T. Child

Journal of Communication Pedagogy

This article discusses what undergraduate students enrolled in a family communication course should learn. It is intended to provide readers with a general direction on how to design or teach a family communication course so that students understand a communication-centered approach to family. This article highlightssome of the foundational theories and concepts grounding most family communication courses, content areas typically addressed when considering the family communication course, possible assignments that might be useful in teaching the course, and relevant issues related to teaching family communication. If instructors thoughtfully consider content and assignment decisions in the family communication course, they have …


“You Have To Cry Before You Teach This Class”: Emotion With Work And Resistance In Teaching Intercultural Communication, Brandi Lawless, Yea-Wen Chen Jan 2019

“You Have To Cry Before You Teach This Class”: Emotion With Work And Resistance In Teaching Intercultural Communication, Brandi Lawless, Yea-Wen Chen

Journal of Communication Pedagogy

In this study, we explore the ways in which Intercultural Communication instructors uniquely experience emotion with work and how this influences their pedagogical approaches to this course. We collected and analyzed interviews with 21 intercultural communication educators across U.S. colleges and universities. We present findings related to the types of resistance present and/or emerging in the intercultural communication classroom, emotional responses to resistance, and strategies for managing and negotiating emotion with work in the Intercultural Communication classroom. We end with discussing implications for teacher training programs designed for the Intercultural Communication classroom.


Pedagogy, Gender, And Communication: Learning And Unlearning Gender, Marian L. Houser, Robert J. Sidelinger, Angela Hosek Jan 2019

Pedagogy, Gender, And Communication: Learning And Unlearning Gender, Marian L. Houser, Robert J. Sidelinger, Angela Hosek

Journal of Communication Pedagogy

Courses in gender communication are designed to enable students to examine the role of gender and gender identity in everyday communication. To aid them to understand gender communication, they should be exposed to at least three foundational areas and supporting content. Sex and gender differences, the social construction of gender, and theoretical gender lenses (biological, psychological, and critical/cultural) are critical foundations that students should grasp to recognize the complexity of gender and gender communication.


Journal Of Communication Pedagogy, Complete Volume, 2019 Jan 2019

Journal Of Communication Pedagogy, Complete Volume, 2019

Journal of Communication Pedagogy

No abstract provided.


Experimental Studies Of Barite Growth Using Hydrothermal Atomic Force Microscopy In Alkali Metal Salt Solutions At 108 C, Sohan Ahmed Jan 2019

Experimental Studies Of Barite Growth Using Hydrothermal Atomic Force Microscopy In Alkali Metal Salt Solutions At 108 C, Sohan Ahmed

Browse all Theses and Dissertations

Barite (BaSO4) growth on the (001) surface was studied under solutions of alkali metal chloride salts (LiCl, NaCl, KCl, RbCl and CsCl) as a function of saturation index and ionic strength of the salts at 108 C. When LiCl was used as the background electrolyte, growth hillocks on the barite surface consisted of both [010] steps and <120> steps at ionic strengths of 0.05 and 0.1 M, but [010] steps were not observed at lower ionic strength. In NaCl solutions, hillocks displayed greater prominence of the [010] steps when compared with LiCl. From the saturation state dependent studies, it was found …


Children As Bargaining Chips, Clare Ryan Jan 2019

Children As Bargaining Chips, Clare Ryan

Articles

The parent- child relationship is one of the most valued and protected relationships in constitutional and family law. At the same time, the state has custodial power over children: a power that is necessary in some cases to protect vulnerable children from danger, neglect, and abandonment. But because the parent-child bond is so powerful, state actors can be tempted to exploit it for their own purposes. Custodial power over children provides state actors with the means to put pressure on the parent by threatening to remove the child. In these circumstances, the state uses the child as a bargaining chip …


The Constitutionalization Of Fatherhood, Dara Purvis Jan 2019

The Constitutionalization Of Fatherhood, Dara Purvis

Faculty Scholarship

Beginning in the 1970s, the Supreme Court heard a series of challenges to family law statutes brought by unwed biological fathers, questioning the constitutionality of laws that treated unwed fathers differently than unwed mothers. The Court’s opinions created a starkly different constitutional status for unwed fathers than for unwed mothers, demanding additional actions and relationships before an unwed father was considered a constitutional father. Although state parentage statutes have progressed beyond their 1970s incarnations, the doctrine created in those family law cases continues to have impact far beyond family law. Transmission of citizenship in the context of immigration law and …


Sonic Hedgehog Is Expressed By Hilar Mossy Cells And Regulates Cellular Survival And Neurogenesis In The Adult Hippocampus, Luis E. Gonzalez-Reyes, Chia-Chu Chiang, Mingming Zhang, Joshua Johnson, Manuel Arrillaga-Tamez, Nicholas H. Couturier, Neha Reddy, Lev Starikov, Jeffrey R. Capadona, Andreas H. Kottmann, Dominique M. Durand Jan 2019

Sonic Hedgehog Is Expressed By Hilar Mossy Cells And Regulates Cellular Survival And Neurogenesis In The Adult Hippocampus, Luis E. Gonzalez-Reyes, Chia-Chu Chiang, Mingming Zhang, Joshua Johnson, Manuel Arrillaga-Tamez, Nicholas H. Couturier, Neha Reddy, Lev Starikov, Jeffrey R. Capadona, Andreas H. Kottmann, Dominique M. Durand

Publications and Research

Sonic hedgehog (Shh) is a multifunctional signaling protein governing pattern formation, proliferation and cell survival during embryogenesis. In the adult brain, Shh has neurotrophic function and is implicated in hippocampal neurogenesis but the cellular source of Shh in the hippocampus remains ill defined. Here, we utilize a gene expression tracer allele of Shh (Shh-nlacZ) which allowed the identification of a subpopulation of hilar neurons known as mossy cells (MCs) as a prominent and dynamic source of Shh within the dentate gyrus. AAV-Cre mediated ablation of Shh in the adult dentate gyrus led to a marked degeneration …


Environmental Factors Influencing College Student Athletes Quality Of Life, Carly Ono, Anthony Sassano, Janine Rebekah Villanueva, Ashton Wolffe Jan 2019

Environmental Factors Influencing College Student Athletes Quality Of Life, Carly Ono, Anthony Sassano, Janine Rebekah Villanueva, Ashton Wolffe

Occupational Therapy | MSOT Capstone Projects

College students face a number of obstacles to achieving success in their desired areas of occupation. However, fulfilling all the responsibilities of their other roles as well may present a risk for occupational imbalances. This is typically the case when examining the lifestyles of collegiate athletes. In this qualitative study, researchers interviewed 15 Dominican University of California (DUoC) college student athletes, playing at the National Collegiate Athletic Association (NCAA) Division II level to assess what environmental factors influence their quality of life (QoL). QoL was determined as the best measure seeing as how it encompasses all components of what deems …


Blended Learning Mediated Fostering Of Students’ Engagement In An Undergraduate Medical Education Module, Lena Jafri, Hafsa Majid, Salman Siddiqi, Najmul Islam, Faraz Khurshid Jan 2019

Blended Learning Mediated Fostering Of Students’ Engagement In An Undergraduate Medical Education Module, Lena Jafri, Hafsa Majid, Salman Siddiqi, Najmul Islam, Faraz Khurshid

Department of Pathology and Laboratory Medicine

Introduction: The study investigated students’ perception of introducing blended learning strategies to engage and motivate them towards lecture halls and Problem Based Learning (PBL) sessions for improving the quality of the overall students’ learning experience.
Methods: A prospective study was conducted at the Aga Khan University Medical College involving a total of one hundred four (104) year II medical students for the Endocrine and Reproduction module in the academic year 2018. This module ran for six weeks. Modifications in teaching methods were made for this module introduced after approval from Endocrine & Reproduction module, year II and curriculum committees. Written …


Quit Doing The Lesson And Start Doing Physics, Katelyn Mccarthy Jan 2019

Quit Doing The Lesson And Start Doing Physics, Katelyn Mccarthy

Dissertations, Master's Theses and Master's Reports

Getting students to shift from doing the lesson to doing science (physics) is not only the goal of science teachers across the state, but it is the goal of the most recent standards released by the state of Michigan. To aid students in shifting from thinking like students to thinking like scientists, this study sought to explore how increased feedback, provided by the teacher on students’ work, as well as feedback provided by the students on their weekly learning, could shift students’ perceptions of science. Students’ perceptions of physics were measured using an adapted Colorado learning attitudes about science survey …


Synthesis Of Oligodeoxynucleotides Containing Sensitive Electrophiles, Shahien Shahsavari Jan 2019

Synthesis Of Oligodeoxynucleotides Containing Sensitive Electrophiles, Shahien Shahsavari

Dissertations, Master's Theses and Master's Reports

Oligodeoxynucleotides (ODNs) containing electrophilic groups are useful in many studies including antisense drug development and DNA/protein interaction. Due to the use of strong nucleophiles for cleavage and deprotection, traditional ODN synthesis methods are not suitable for their preparation. To solve this problem, a new ODN synthesis technology using the 1,3- dithiane-2-yl-methoxycarbonyl (Dmoc) function as protecting groups and linker has been developed. Furthermore, Dmoc-derivatives were developed to demonstrate the feasibility of the technology. The Dmoc and Dmoc derivative functions are stable under all ODN synthesis conditions using the phosphoramidite chemistry. Upon oxidation of the sulfides in them, because of the drastically …


Formative Interests And Pathways To Natural Resources Careers Among Racial And Ethnic Minorities, Laura Burmann Jan 2019

Formative Interests And Pathways To Natural Resources Careers Among Racial And Ethnic Minorities, Laura Burmann

Dissertations, Master's Theses and Master's Reports

Land use, values, and ethics vary across cultures; however, those making natural resource (NR) management decisions are often not representative of the diversity of people who live on the land. Diversifying the workforce is a step towards ensuring management decisions and policies are inclusive of all peoples; however, few people from minority groups are pursuing degrees related to NR management. The purpose of this study is to assess factors affecting the decisions to pursue careers in NR fields among historically underrepresented groups of people, with an emphasis on the role that youth environmental education (EE) programs play in creating career …


Toward An Understanding Of The Clinical Relevance Of Nitric Oxide (No) Measurements In In Vitro Cell Culture Studies, Maria Paula Kwesiga Jan 2019

Toward An Understanding Of The Clinical Relevance Of Nitric Oxide (No) Measurements In In Vitro Cell Culture Studies, Maria Paula Kwesiga

Dissertations, Master's Theses and Master's Reports

Diabetic foot ulcers (DFU) are one of the most challenging complications associated with diabetes mellitus (DM). Every 1 in 4 patients with DM are expected to develop an ulcer in their life time. The time course of healing is on average 90 to 120 days which increases the risks of infection, amputations and death. Nitric oxide (NO) is a signaling molecule produced in the body that has been established in the literature to serve many roles in the body, including as a vasodilator, neurotransmitter immune modulator and antimicrobial agent. Emerging evidence has shown that NO is indispensable in every stage …


Microborings As Indication Of Cryptic Life Modes In The Foraminifer Orbitoides:Maastrichtian Sediments Of The Haymana And Nallıhan Districts (Ankara, Turkey), Muhi̇tti̇n Görmüş, Huri̇ye Demi̇rcan, Yusuf Kağan Kadioğlu, Fuzuli̇ Yağmurlu, Muhammed Sami̇ Us Jan 2019

Microborings As Indication Of Cryptic Life Modes In The Foraminifer Orbitoides:Maastrichtian Sediments Of The Haymana And Nallıhan Districts (Ankara, Turkey), Muhi̇tti̇n Görmüş, Huri̇ye Demi̇rcan, Yusuf Kağan Kadioğlu, Fuzuli̇ Yağmurlu, Muhammed Sami̇ Us

Turkish Journal of Earth Sciences

Widespread Maastrichtian siliciclastics and carbonates cropping out in the Haymana (S Ankara) and Nallıhan (NW Ankara) districts in the northwest and central Anatolia basins include rich Orbitoides occurrences. Microborings in the Orbitoides tests are interesting to notify. In this study, the details of their morphologic structures were investigated. Microborings were analyzed in more than 650 equatorial thin sections of the Orbitoides tests and 100 hard rock thin sections. The abundance of microborings increases in the siliciclastics towards the Cretaceous/Palaeogene boundary (K/Pg). They were identified as Maeandropolydora osmaneliensis Nielsen and Görmüş, Maeandropolydora isp. Curvichnus semorbis Nielsen, Oichnus simplex Bromley, Oichnus isp. …


Mineralogy And Geochemistry Of Metalliferous Sedimentary Rocks From The Uppercretaceous Vms Deposits Of The Eastern Pontides (Ne Turkey), Mustafa Kemal Revan, Yurdal Genç, Okan Deli̇baş, Valeri̇y V. Maslennikov, Nuri̇ya R. Ayupova, Okan Zi̇mi̇toğlu Jan 2019

Mineralogy And Geochemistry Of Metalliferous Sedimentary Rocks From The Uppercretaceous Vms Deposits Of The Eastern Pontides (Ne Turkey), Mustafa Kemal Revan, Yurdal Genç, Okan Deli̇baş, Valeri̇y V. Maslennikov, Nuri̇ya R. Ayupova, Okan Zi̇mi̇toğlu

Turkish Journal of Earth Sciences

Metalliferous sedimentary rocks, despite being limited in scope, are important stratigraphic horizons within the volcanogenic massive sulfide (VMS) deposits in the Upper Cretaceous volcanic belt of the Eastern Pontides. The metalliferous sedimentary rocks compose a distinctive genetic class. The abundance of such rocks in the Eastern Pontide district provides a basis for study and description that may be more widely applied in other VMS districts. The metalliferous sedimentary rocks generally form layers less than 1.5 m thick above stratiform massive sulfide ores. The metalliferous sediments are largely composed of quartz and hematite. While the Si ± Fe content of sediments …


Mindfulness-Based Meditation And Its Effects On College Students, Jordan Sieja Jan 2019

Mindfulness-Based Meditation And Its Effects On College Students, Jordan Sieja

Senior Honors Theses and Projects

Mindfulness-based meditation is a practice that has been proven to have many physiological and psychological health benefits such as positive lifestyle habits, increased mindfulness, decrease in substance use, decrease in stress, better mood states, and enhanced coping strategies. University students undergo many different types of stressors at one time such as financial instability, identity development, academic pressures, parental expectations, and racial/cultural differences (Kadison & Geronimo, 2004). Intense stress when it is not coped with effectively can lead to many different health problems physically and mentally. The current study evaluates the effects of mindfulness meditation with undergraduate students and it was …


The Effects Of Tumor Growth On Stress Response, Body Size, And Fat Content In Caenorhabditis Elegans, Reem Yassine Jan 2019

The Effects Of Tumor Growth On Stress Response, Body Size, And Fat Content In Caenorhabditis Elegans, Reem Yassine

Senior Honors Theses and Projects

Tumorous growth affects nearby healthy tissues, as seen in wasting disease experienced by cancer patients, but the underlying mechanisms are not well understood. We studied tumor growth in C.elegans, a microscopic worm that shares many genes with humans and has the ability to grow tumors in its reproductive system. To test whether tumors cause stress in nearby tissues, we used genetic crosses to create strains containing tumors and fluorescent-based stress reporters for the following physiological stresses: endoplasmic reticulum unfolded protein response (hsp-4p::GFP), heat shock (hsp-6.2p::GFP), and infection (irg-1p::GFP). We found that expression of …


The Biocultural Evolution Of Inflammatory Bowel Diseases, Amanda Rielinger Jan 2019

The Biocultural Evolution Of Inflammatory Bowel Diseases, Amanda Rielinger

Senior Honors Theses and Projects

Inflammatory bowel diseases (IBD), such as Crohn's disease and ulcerative colitis, are described as abnonnal immune responses to the gastrointestinal microbiota. The etiology of IBD is unknown; however, it is associated with Western, industrialized societies. A better understanding of the origins and treatments of IBD can lead to improved health outcomes. This paper seeks to examine IBD from a cultural, environmental, and evolutionary perspective. The effects of cultural and environmental factors, such as diagnostic practices, diet, breastfeeding practices, antibiotic use, appendectomy, and environmental radiation exposure on the risk of developing IBD are discussed. The efficacy of various treatments for IBD …


Editorial: We Can Do Better Than "Adolescence", Ben Anderson-Nathe, Grant Charles Jan 2019

Editorial: We Can Do Better Than "Adolescence", Ben Anderson-Nathe, Grant Charles

School of Social Work Faculty Publications and Presentations

Editorial. The author discusses the concept of adolescence and its acceptance as a biological imperative, a developmental mandate, and an explanation for young people's behavior. Topics discussed include the shift of the fundamentals of labor from largely agrarian to predominantly industrial forms, the 1904 naming of adolescence as a distinct life stage in the human experience, and adolescence as the default starting point for most adult interactions with youth in the academic and practice literatures.


Quality Of Life And Stigma Among People Living With Hiv/Aids In Iran, Mohammad Ebrahimi Kalan, Jian Han, Ziyad Ben Taleb, Kristopher P. Fennie, Mohammad Asghari Jafarabadi, Maryam Dastoorpoor, Nima Hajhashemi, Mitra Naseh, Shahnaz Rimaz Jan 2019

Quality Of Life And Stigma Among People Living With Hiv/Aids In Iran, Mohammad Ebrahimi Kalan, Jian Han, Ziyad Ben Taleb, Kristopher P. Fennie, Mohammad Asghari Jafarabadi, Maryam Dastoorpoor, Nima Hajhashemi, Mitra Naseh, Shahnaz Rimaz

School of Social Work Faculty Publications and Presentations

Background: Stigma against HIV profoundly affects the quality of life (QOL) of people living with HIV/AIDS (PLWHA). We aimed to assess the factors associated with QOL in PLWHA in Iran, specifically HIV-related stigma, sociodemographic and clinical characteristics.

Methods: Two hundred PLWHA participated in this cross-sectional study. Data were collected using sociodemographic, stigma, and WHO-QOL-BREF questionnaires. Correlations, ANOVAs, and Student’s t-distribution tests were performed as bivariate analyses. We employed stepwise multiple linear regression analysis to explore the main factors associated with QOL domains.

Results: Six domains of QOL were negatively correlated with three domains of stigma (p < 0.001 for all). Stepwise multiple linear regression revealed that, after adjusting for con-founders, lack of healthcare insurance, having no basic knowledge of HIV/AIDs prior to diagnosis, low monthly income of participants and family, and stigma (blaming and distancing, discrimination, and fear) were associated with low mean score of different domains of QOL.

Conclusion …


On The Brink Of Extinction: The Fate Of The Pacific Northwest's Southern Resident Killer Whales, Sabrina Wilk Jan 2019

On The Brink Of Extinction: The Fate Of The Pacific Northwest's Southern Resident Killer Whales, Sabrina Wilk

Pomona Senior Theses

The killer whales that roam the northeastern Pacific Ocean have been the objects of studies since the 1970s, making them the most well-studied population of orcas in the world. Three distinct ecotypes of killer whales (Orcinus orca), known as residents, transients, and offshores, share these waters. The ecotypes are morphologically and behaviorally distinct to the extent that some scientists consider them separate species, with residents eating salmon, transients specializing on marine mammals, and offshores preferring Pacific sleeper sharks and Pacific halibut. Resident populations have endeared themselves to the region's locals with their striking black and white markings and …


Fragile Oceans, Synthetic Flotsam And Microbial Collaboration – Explorations In The Visual Communication Of The Plastic Crisis, Ivan Langesfeld Jan 2019

Fragile Oceans, Synthetic Flotsam And Microbial Collaboration – Explorations In The Visual Communication Of The Plastic Crisis, Ivan Langesfeld

Pomona Senior Theses

Scientific evidence that the ocean plastic crisis is larger in scale and more sinister than previously thought continues to mount, but the rate of plastic production is only rising. What will it take to decisively turn the tide against plastic? We need scientists, politicians, and industry changemakers to continue producing knowledge and positive change in the industry, but we need to go further still. This thesis explores art as an alternative visual communication strategy with the capacity to encourage curiosity, empathy, and positive engagement with the issue of ocean plastics. The series of work explores bacterial bioluminescence as an artistic …


A Selected Comparison Of Music Librarians' And Musicologists' Self-Archiving Practices, Rachel E. Scott Jan 2019

A Selected Comparison Of Music Librarians' And Musicologists' Self-Archiving Practices, Rachel E. Scott

Faculty and Staff Publications – Milner Library

The importance of open access (OA) advocacy is well-documented in the literature of academic librarianship, but previous research shows that librarians' OA behaviors are less conclusive. This article compares the self-archiving practices of music librarians and musicologists to see how librarians rank in OA adoption. Availability of articles published from 2013 to 2017 in six green OA journals in music librarianship and musicology indicates a need for continued advocacy and enhanced understanding of OA policies and opportunities.


Judicial Bias Against Lgbt Parents In Custody Disputes, Amy Maitner Jan 2019

Judicial Bias Against Lgbt Parents In Custody Disputes, Amy Maitner

University of Florida Journal of Law & Public Policy

No abstract provided.


Articulation And Transfer In Tennessee Higher Education 2018 Report, Tennessee. Higher Education Commission. Jan 2019

Articulation And Transfer In Tennessee Higher Education 2018 Report, Tennessee. Higher Education Commission.

Academic Programs and Workforce Reports

No abstract provided.


The Bacterial Symbionts Of Closely Related Hydrothermal Vent Snails With Distinct Geochemical Habitats Show Broad Similarity In Chemoautotrophic Gene Content, Roxanne A. Beinart, Chengwei Luo, Konstantinos T. Konstantinidis, Frank J. Stewart, Peter R. Girguis Jan 2019

The Bacterial Symbionts Of Closely Related Hydrothermal Vent Snails With Distinct Geochemical Habitats Show Broad Similarity In Chemoautotrophic Gene Content, Roxanne A. Beinart, Chengwei Luo, Konstantinos T. Konstantinidis, Frank J. Stewart, Peter R. Girguis

Graduate School of Oceanography Faculty Publications

Symbiosis has evolved between a diversity of invertebrate taxa and chemosynthetic bacterial lineages. At the broadest level, these symbioses share primary function: the bacterial symbionts use the energy harnessed from the oxidation of reduced chemicals to power the fixation of inorganic carbon and/or other nutrients, providing the bulk of host nutrition. However, it is unclear to what extent the ecological niche of the host species is influenced by differences in symbiont traits, particularly those involved in chemoautotrophic function and interaction with the geochemical environment. Hydrothermal vents in the Lau Basin (Tonga) are home to four morphologically and physiologically similar snail …


Archaea Dominate Oxic Subseafloor Communities Over Multimillion-Year Time Scales, Aurèle Vuillemin, Scott D. Wankel, Ömer K. Coskun, Tobias Magritsch, Sergio Vargas, Emily R. Estes, Arthur J. Spivack, David C. Smith, Robert Pockalny, Richard W. Murray, Steven D'Hondt, William D. Orsi Jan 2019

Archaea Dominate Oxic Subseafloor Communities Over Multimillion-Year Time Scales, Aurèle Vuillemin, Scott D. Wankel, Ömer K. Coskun, Tobias Magritsch, Sergio Vargas, Emily R. Estes, Arthur J. Spivack, David C. Smith, Robert Pockalny, Richard W. Murray, Steven D'Hondt, William D. Orsi

Graduate School of Oceanography Faculty Publications

Ammonia-oxidizing archaea (AOA) dominate microbial communities throughout oxic subseafloor sediment deposited over millions of years in the North Atlantic Ocean. Rates of nitrification correlated with the abundance of these dominant AOA populations, whose metabolism is characterized by ammonia oxidation, mixotrophic utilization of organic nitrogen, deamination, and the energetically efficient chemolithoautotrophic hydroxypropionate/hydroxybutyrate carbon fixation cycle. These AOA thus have the potential to couple mixotrophic and chemolithoautotrophic metabolism via mixotrophic deamination of organic nitrogen, followed by oxidation of the regenerated ammonia for additional energy to fuel carbon fixation. This metabolic feature likely reduces energy loss and improves AOA fitness under energy-starved, oxic …