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Llusd Articulator - Volume 31, Number 2, Loma Linda University School Of Dentistry

Articulator (Dentistry)

Contents:

5 | Dean's Message
8 | Faculty arrive and faculty advance
10 | Mary Hartwell concludes 40 years
11 | LLUSD's 2020 virtual commencement
26 | Student research surmounts the virus
38 | The legacies left by
Dr. Donald Peters,
Dr. Doug Roberts, &
Dr. Elmer Kelln

A Review And Evaluation Of Techniques For Improved Feature Detection In Mass Spectrometry Data, Annika R. Tostengard, Rob Smith

Graduate Student Theses, Dissertations, & Professional Papers

Mass spectrometry (MS) is used in analysis of chemical samples to identify the molecules present and their quantities. This analytical technique has applications in many fields, from pharmacology to space exploration. Its impacts on medicine are particularly significant, since MS aids in the identification of molecules associated with disease; for instance, in proteomics, MS allows researchers to identify proteins that are associated with autoimmune disorders, cancers, and other conditions. Since the applications are so wide-ranging and the tool is ubiquitous across so many fields, it is critical that the analytical methods used to collect data are sound.

Data analysis in …

Promoting Physical Activity Among American Indian Older Adults, Maja R. Pedersen

Graduate Student Theses, Dissertations, & Professional Papers

Background: Physical activity (PA) promotion is acknowledged as a critical component to improve public health among the growing population of older adults in the U.S. American Indian and Alaska Native (AIAN) older adults experience disproportionately high rates of chronic disease and disability compared with non-Hispanic White peers, and demonstrate lower levels of PA, indicating a need for examination of unique factors influencing their PA behavior.

Purpose: This study revealed the current state of PA intervention research among AIAN older adults in the U.S. and utilized best practices to identify factors that can influence the development, adaptation, and implementation of PA …

Investigating The Spatial Behavior And Habitat Use Of The Matschie’S Tree-Kangaroo (Dendrolagus Matschiei) Using Gps Collars And Unmanned Aircraft Systems (Uas), Jonathan B. Byers

Graduate Student Theses, Dissertations, & Professional Papers

Understanding the movement patterns and habitat needs of the endangered Matschie’s tree-kangaroo (Dendrolagus matschiei) is important for their conservation and management. Endemic to the montane cloud forests of the Huon Peninsula in northeastern Papua New Guinea, these elusive arboreal marsupials are tremendously challenging to study using traditional observational methods.

This study is an assessment of novel techniques to overcome the significant challenges to in-situ data collection in remote and rugged tropical cloud forests. Animal locations are remotely tracked using purpose built altitude and motion logging GPS collars and habitat structure data is measured using photogrammetry from small Unmanned Aircraft …

The Effects Of Heavy Metal Contamination In Soil On Dna Degradation After Decomposition, Samantha Hofland

Graduate Student Theses, Dissertations, & Professional Papers

The application of DNA is an ever-expanding field of research with many implications in the field of forensic investigation. Research into DNA obtained from soil is ongoing and suggests a new avenue in forensic investigation. This research seeks to understand the effects of heavy metal on the preservation of DNA within soil after decomposition of remains. Using pigs as a proxy for human remains, the effects of heavy metal contamination on the microbial environment and endogenous pig DNA was observed. This gave broad insight into the effect of surface burial and Western Montana; summer climate has on DNA degradation.

The Place Of Community Food Forests: A Review And Case Study Of Community Food Forests And Their Untapped Potential, Sarah Eiden

Graduate Student Theses, Dissertations, & Professional Papers

As population grows, the borders of urban and peri-urban areas continue to expand. The UN projects that by 2050 more than 68% of the world population is expected to live in urban areas (UN, 2018). Presently, urban centers are heterotrophic, or highly consumptive of products produced elsewhere, making them one of the most pressing challenges to global sustainability (Wu, 2008). With an ever-increasing imperative for more sustainable food production, multi-use edible green landscapes and other autotrophic, or self-feeding urban agriculture initiatives, are gaining attention and creative practice to incorporate a diversity of ecosystem services (ES). Community food forests (CFF) are …

Modal Understanding Of Robustness Analysis, Grayson O'Reilly

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

Aquatic Locomotion In Birds – Biomechanics, Morphometrics, And Evolution, Anthony Barrett Lapansky

Graduate Student Theses, Dissertations, & Professional Papers

The entire diversity of life on earth exists in air or water. Whether an organism lives in air or water provides the most fundamental description of its physical world and establishes an organism’s ecological niche on the most essential level. Because these two fluids are vastly different from one another, they also dictate, via the process of natural selection, the morphology and physiology of the organisms which call them home. By studying how organisms interact with these fluids – to locomote or obtain food, for example – we have the ability to not only link organism form and function, but …

Large Carnivore Recolonization Reshapes Population And Community Dynamics In The Rocky Mountains: Implications For Harvest Management, Tyler James Clark

Graduate Student Theses, Dissertations, & Professional Papers

Large carnivores are re-colonizing their historical range globally, following decades of systematic eradication. The subsequent expansion of large carnivore populations is creating complex predator-prey interactions by trophically upgrading previously simpler food webs. Overlap between large carnivore and human range expansion is increasing human-carnivore conflicts, with many calling for large carnivore management to mitigate predation on harvested ungulates. However, the complexity of food web interactions in trophically upgraded systems coupled with independent management strategies for each species makes it difficult to determine what are optimal management strategies in these systems. These issues are further complicated by expectations of harvested ungulate densities …

Effects Of Wolf And Grizzly Bear Recovery On Cougars In A Multi-Use System, Jennifer A. Feltner

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

Hiding The Authentic Self: Concealment Of Gender And Sexual Identity And Its Consequences For Authenticity And Psychological Well-Being, James Michael Brennan

Graduate Student Theses, Dissertations, & Professional Papers

Background: Concealment of gender and sexual identity is a reaction to societal stigma against gender and sexual minority (GSM) identities. Despite initially protecting against stigma, concealment has longterm psychological consequences. These consequences are potentially attributable to the psychological damage incurred from a reduced sense of authenticity among those who conceal their gender and sexual identity. Authenticity is compromised by concealment, serving to disrupt a person’s self-concept, as external behavior and an innate sense of self diverge. On top of that, an individual’s mental and emotional states may be impacted by these discrepancies. Additionally, concealment undermines the pursuit of intrinsically-motivated, goal-directed …

Lepidopteran Granivory Reduces Seed Counts In A Rare Species Of Riparian Scour Prairies, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine

Faculty Journal Articles

In Pennsylvania Baptisia australis var. australis is found along only four waterways: the Allegheny River, Youghiogheny River, Clarion River, and Red Bank Creek. Because of its limited distribution and small number of extant populations, the species is considered state-threatened in Pennsylvania. In addition, the riparian prairie habitat that Pennsylvania Baptisia australis var. australis is restricted to is also in decline and considered vulnerable. Because of these conservation concerns, insights into the natural history of the taxon in the state is valuable and will inform conservation efforts. Field surveys and fruit collections along the Allegheny River and herbarium collections were used …

Lessons From Four Decades Of Monitoring Vegetation And Fire: Maintaining Diversity And Resilience In Florida’S Uplands, Warren G. Abrahamson Ii, Christy R. Abrahamson, Matthew A. Keller

Faculty Journal Articles

Worldwide, humans are altering the fire regimes (fire-return intervals, severity, seasonality) of fire-prone ecosystems, fragmenting natural landscapes, and altering climates. Efforts to restore fire regimes in natural areas are usually guided by fire management plans (FMP) that rely on prescribed burning. Despite the common use of FMPs, limited efforts have gone to assessing vegetative and faunal responses. While some insights into responses to fire from short-term studies are available, there is less knowledge about FMP outcomes applied over multiple decades. Peninsular Florida hosts many fire-prone communities including globally threatened Florida scrub. We repeatedly sampled species composition and abundance during a …

Multiple Complementary Studies Clarify Which Co-Occurring Congener Presents The Greatest Hybridization Threat To A Rare Texas Endemic Wildflower (Hibiscus Dasycalyx: Malvaceae), Melody P. Sain, Julia Norrell-Tober, Katherine Barthel, Megan Seawright, Alyssa Blanton, Kate L. Hertweck, John S. Placyk, Jr., Randall Small, Lance R. Williams, Marsha G. Williams, Joshua A. Banta

Biology Faculty Publications and Presentations

The Neches River Rose Mallow (Hibiscus dasycalyx) is a rare wildflower endemic to Texas that is federally protected in the U.S.A. While previous work suggests that H. dasycalyx may be hybridizing with its widespread congeners, the Halberd-leaved Rose Mallow (H. laevis) and the Woolly Rose Mallow (H. moscheutos), this has not been studied in detail. We evaluated the relative threats to H. dasycalyx posed by hybridization with H. laevis and H. moscheutos by 1) examining their relatedness to one another via modern phylogenomic methods, 2) examining their ecological (dis)similarities to one another using ecological niche modeling, and 3) looking for …

Internet Memes: Leaflet Propaganda Of The Digital Age, Joshua Troy Nieubuurt

English Faculty Publications

Internet memes are one of the latest evolutions of “leaflet” propaganda and an effective tool in the arsenal of digital persuasion. In the past such items were dropped from planes, now they find their way into social media across multiple platforms and their territory is global. Internet memes can be used to target specific groups to help build and solidify tribal bonds. Due to the ease of creation, and their ability to constantly reaffirm axiomatic tribal ideas, they have become an adroit tool allowing for mass influence across international borders. This text explores the link between internet memes and their …

The (Mis) Representation Of Racialized Minorities: Barbie Dolls As Social Problems In India, Namrata Ashvinbhai Bhadania

English Faculty Publications

The relation between commodities and consumers is directly related to the transactional relationship between kids and their interaction with the toys. The paper aims to critique how female representation through Barbie Dolls in popular culture shapes female identity. Production and consumption of Barbie dolls in India became a way of socializing mechanism to educate young Indian girls on the concept of beauty. A notion of beauty is attached to blue eyes, skinny waist, and fair skin giving rise to “American Exceptionalism” (Madsen, 2009, p. 14), where the model nation conceptualizes itself though national identity where perceiver compels to transform themselves …

Generic Design Methodology For Smart Manufacturing Systems From A Practical Perspective. Part Ii—Systematic Designs Of Smart Manufacturing Systems, Zhuming Bi, Wen-Jun Zhang, Chong Wu, Chaomin Luo, Lida Xu

Information Technology & Decision Sciences Faculty Publications

In a traditional system paradigm, an enterprise reference model provides the guide for practitioners to select manufacturing elements, configure elements into a manufacturing system, and model system options for evaluation and comparison of system solutions against given performance metrics. However, a smart manufacturing system aims to reconfigure different systems in achieving high-level smartness in its system lifecycle; moreover, each smart system is customized in terms of the constraints of manufacturing resources and the prioritized performance metrics to achieve system smartness. Few works were found on the development of systematic methodologies for the design of smart manufacturing systems. The novel contributions …

Biology And Molecular Biology Of Ixodes Scapularis, Daniel E. Sonenshine, Ladislav Šimo, Justin D. Radolf (Ed.), D. Scott Samuels (Ed.)

Biological Sciences Faculty Publications

This chapter describes the biology of the tick Ixodes scapularis in relation to its role as the vector of the Lyme disease agent, Borrelia burgdorferi. Following a review of the internal anatomy of the tick, we review basic molecular processes that contribute to an understanding of the dynamics of the tick's specialized parasitic processes, including attachment behavior, salivation; silencing of host anti-inflammatory responses to enable blood ingestion at the dermal feeding site; hemoglobin digestion and reproduction. The chapter is divided into three parts: 1) systematic and anatomical characteristics of ticks; 2) host finding, attachment, salivary disruption of host defenses, blood …

Scoping Review Of Distribution Models For Selected Amblyomma Ticks And Rickettsial Group Pathogens, Catherine A. Lippi, Holly D. Gaff, Alexis L. White, Sadie J. Ryan

Biological Sciences Faculty Publications

The rising prevalence of tick-borne diseases in humans in recent decades has called attention to the need for more information on geographic risk for public health planning. Species distribution models (SDMs) are an increasingly utilized method of constructing potential geographic ranges. There are many knowledge gaps in our understanding of risk of exposure to tick-borne pathogens, particularly for those in the rickettsial group. Here, we conducted a systematic scoping review of the SDM literature for rickettsial pathogens and tick vectors in the genus Amblyomma. Of the 174 reviewed articles, only 24 studies used SDMs to estimate the potential extent …

Double Anus In An Ixodes Scapularis Nymph, A Medically Important Tick Vector, Vikas Taank, Frank A. Lattanzio, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

Background: Ixodes scapularis ticks are medically important arthropod vectors that transmit several pathogens to humans. The observations of morphological abnormalities, including nanism, missing leg, extra leg, and gynandromorphism, have been reported in these ticks. In this study, we report the presence of two anuses in a laboratory-reared I. scapularis nymph.

Results: Larval ticks were allowed to feed on mice and to molt to nymphs. Two anuses were observed in one of the freshly molted nymphs. Stereo and scanning electron microscopy confirmed the presence of two anuses in one nymph within a single anal groove.

Conclusions: This report confirms the rare …

Global Extinction Risk For Seahorses, Pipefishes And Their Near Relatives (Syngnathiformes), Riley A. Pollom, Gina M. Ralph, Caroline M. Pollock, Amanda C.J. Vincent

Biological Sciences Faculty Publications

Few marine taxa have been comprehensively assessed for their conservation status, despite heavy pressures from fishing, habitat degradation and climate change. Here we report on the first global assessment of extinction risk for 300 species of syngnathiform fishes known as of 2017, using the IUCN Red List criteria. This order of bony teleosts is dominated by seahorses, pipefishes and seadragons (family Syngnathidae). It also includes trumpetfishes (Aulostomidae), shrimpfishes (Centriscidae), cornetfishes (Fistulariidae) and ghost pipefishes (Solenostomidae). At least 6% are threatened, but data suggest a mid-point estimate of 7.9% and an upper bound of 38%. Most of the threatened species are …

Diet Of Long-Eared Owl And Common Kestrel In An Urban Landscape (Ukraine), Ivan Zahorodnyi, Oleksii Dubovyk, Ivan Komarnytskyi, Ihor Dykyy

Biological Sciences Faculty Publications

In the present study we performed a comparative dietary analysis of two predatory birds, the Long-eared Owl (Asio otus) and the Common Kestrel (Falco tinnunculus) in the district of Lviv city. We found that the Long-eared Owl and the Common Kestrel are typical small mammal specialists within the urban ecosystem. Considering the abundance and biomass of prey, small mammals comprise 98.4% of the Long-eared Owl’s diet. The species composition of mammals coincides almost 50% in the food intake comparison of the two birds. It has been established that the main prey of both species is the …

Triple Oxygen Isotope Measurements (Δ'17O) Of Body Water Reflect Water Intake, Metabolism, And Δ18O Of Ingested Water In Passerines, Pablo Sabat, Seth D. Newsome, Stephanie Pinochet, Roberto Nespolo, Juan Carlos Sanchez-Hernandez, Karen Maldonado, Alexander R. Gerson, Zachary D. Sharp, John P. Whiteman

Biological Sciences Faculty Publications

Understanding physiological traits and ecological conditions that influence a species reliance on metabolic water is critical to creating accurate physiological models that can assess their ability to adapt to environmental perturbations (e.g., drought) that impact water availability. However, relatively few studies have examined variation in the sources of water animals use to maintain water balance, and even fewer have focused on the role of metabolic water. A key reason is methodological limitations. Here, we applied a new method that measures the triple oxygen isotopic composition of a single blood sample to estimate the contribution of metabolic water to the body …

Spatio-Temporal Modelling Of Tick Life-Stage Count Data With Spatially Varying Coefficients, Thabo Lephoto, Henry Mwambi, Oliver Bodhlyera, Holly Gaff

Biological Sciences Faculty Publications

There is a vast amount of geo-referenced data in many fields of study including ecological studies. Geo-referencing is usually by point referencing; that is, latitudes and longitudes or by areal referencing, which includes districts, counties, states, provinces and other administrative units. The availability of large geo-referenced datasets for modelling has necessitated the development and application of spatial statistical methods. However, spatial varying coefficients models exploring the abundance of tick counts remain limited. In this study we used data that was collected and prepared by researchers in the Department of Biological Sciences from the Old Dominion University, Virginia, USA. We modelled …

Variation In Coral Thermotolerance Across A Pollution Gradient Erodes As Coral Symbionts Shift To More Heat-Tolerant Genera, Melissa S. Naugle, Thomas A. Oliver, Daniel J. Barshis, Ruth D. Gates, Cheryl A. Logan

Biological Sciences Faculty Publications

Phenotypic plasticity is one mechanism whereby species may cope with stressful environmental changes associated with climate change. Reef building corals present a good model for studying phenotypic plasticity because they have experienced rapid climate-driven declines in recent decades (within a single generation of many corals), often with differential survival among individuals during heat stress. Underlying differences in thermotolerance may be driven by differences in baseline levels of environmental stress, including pollution stress. To examine this possibility, acute heat stress experiments were conducted on Acropora hyacinthus from 10 sites around Tutuila, American Samoa with differing nutrient pollution impact. A threshold-based heat …

Self And Microbiota-Derived Epitopes Induce Cd4⁺ T Cell Anergy And Conversion Into Cd4⁺Foxp3⁺ Regulatory Cells, Michal P. Kuczma, Edyta A. Szurek, Anna Cebula, Vu L. Ngo, Maciej Pietrzak, Piotr Kraj, Timothy L. Denning, Leszek Ignatowicz

Biological Sciences Faculty Publications

The physiological role of T cell anergy induction as a key mechanism supporting self-tolerance remains undefined, and natural antigens that induce anergy are largely unknown. In this report, we used TCR sequencing to show that the recruitment of CD4⁺CD44⁺Foxp3⁻CD73⁺FR4⁺ anergic (Tan) cells expands the CD4⁺Foxp3⁺ (Tregs) repertoire. Next, we report that blockade in peripherally-induced Tregs (pTregs) formation due to mutation in CNS1 region of Foxp3 or chronic exposure to a selecting self-peptide result in an accumulation of Tan cells. Finally, we show that microbial antigens from Akkermansia muciniphila …

Interaction Between Genetic Risk Scores For Reduced Pulmonary Function And Smoking, Asthma And Endotoxin, Sinjini Sikdar, Annah B. Wyss, Mi Kyeong Lee, Thanh T. Hoang, Marie Richards, Laura E. Beane Freeman, Christine Parks, Peter S. Thorne, John L. Hankinson, David M. Umbach, Alison Motsinger-Reif, Stephanie J. London

Mathematics & Statistics Faculty Publications

Rationale Genome-wide association studies (GWASs) have identified numerous loci associated with lower pulmonary function. Pulmonary function is strongly related to smoking and has also been associated with asthma and dust endotoxin. At the individual SNP level, genome-wide analyses of pulmonary function have not identified appreciable evidence for gene by environment interactions. Genetic Risk Scores (GRSs) may enhance power to identify gene–environment interactions, but studies are few.

Methods We analysed 2844 individuals of European ancestry with 1000 Genomes imputed GWAS data from a case–control study of adult asthma nested within a US agricultural cohort. Pulmonary function traits were FEV₁, …

Potentiometric Biosensing Of Ascorbic Acid, Uric Acid, And Cysteine In Microliter Volumes Using Miniaturized Nanoporous Gold Electrodes, Christopher J. Freeman, Borkat Ullah, Md. Shafiul Islam, Maryanne M. Collinson

Chemistry & Biochemistry Faculty Publications

Potentiometric redox sensing is a relatively inexpensive and passive approach to evaluate the overall redox state of complex biological and environmental solutions. The ability to make such measurements in ultra-small volumes using high surface area, nanoporous electrodes is of particular importance as such electrodes can improve the rates of electron transfer and reduce the effects of biofouling on the electrochemical signal. This work focuses on the fabrication of miniaturized nanoporous gold (NPG) electrodes with a high surface area and a small footprint for the potentiometric redox sensing of three biologically relevant redox molecules (ascorbic acid, uric acid, and cysteine) in …

Association Between Sleep Quality And Dorsal Default Mode Network In College Students, Anna Klets

College of Education and Human Sciences: Dissertations, Theses, and Student Research

College students often have poor sleep quality, which may change resting state functional connectivity network in the brain. Prior research demonstrated that sleep is associated with structural and functional changes in some specific brain subareas, which are involved in the dorsal default mode network (dDMN). However, no study to date has comprehensively examined all possible individual pairs of functional connectivity in the dDMN in relation to sleep quality among college students. Therefore, the present study hypothesized that sleep quality in college students was linked to any resting state functional connectivity in the dDMN.

Forty nine college students (25 females) underwent …

Individual Differences In Social Responsiveness, Social Experiences, And Oxytocin System Genetic Variation In Depression Symptom Severity, Grace Sullivan

Department of Psychology: Dissertations, Theses, and Student Research

Social experiences including discrimination, low social support, and interpersonal conflict are reliable predictors of depression symptom severity (Costello, 1982; Monroe, Rohde, Seeley, & Lewinsohn, 1999; Phifer & Murrell, 1986). However, individual differences may buffer against or exacerbate risk (Pluess & Belsky, 2015). A more holistic and dimensional approach, in line with modern perspectives on mental health (Kircanski, LeMoult, Ordaz, & Gotlib, 2017), requires an investigation of individual differences that moderate associations of positive and negative social experiences with depression symptom severity. This dissertation assesses relative contributions of social experiences (low social support, discrimination, childhood trauma, and sexual objectification) to variation …