Biology Commons^™

The Ecology Of Infancy And Early Childhood In Rural Senegal; A Five Year Old Can Boot But Not Foot, An Exploration Of Where Biology Meets Culture, Heather Mills

Independent Study Project (ISP) Collection

This research project explores the life stages of infancy and early childhood in the village of Ndiane in the Thies region of Senegal. I will discuss how biology meets culture to influence children, parenting styles, and expectations of the life stage. How does ecology, the interaction of physical, biological and cultural landscapes, characterize childhood and the intertwined belief systems that influence parenting? The information was gathered using a combination of participant observation and free list interviews.

Acute Effects Of Tio2 Nanomaterials On The Viability And Taxonomic Composition Of Aquatic Bacterial Communities Assessed Via High-Throughput Screening And Next Generation Sequencing, Binh Chu, Tiezheng Tong, Jean-François Gaillard, Kimberley A. Gray, John J. Kelly

Biology: Faculty Publications and Other Works

The nanotechnology industry is growing rapidly, leading to concerns about the potential ecological consequences of the release of engineered nanomaterials (ENMs) to the environment. One challenge of assessing the ecological risks of ENMs is the incredible diversity of ENMs currently available and the rapid pace at which new ENMs are being developed. High-throughput screening (HTS) is a popular approach to assessing ENM cytotoxicity that offers the opportunity to rapidly test in parallel a wide range of ENMs at multiple concentrations. However, current HTS approaches generally test one cell type at a time, which limits their ability to predict responses of …

Phenotypic Robustness And The Assortativity Signature Of Human Transcription Factor Networks, Dov A. Pechenick, Joshua L. Payne, Jason H. Moore

Dartmouth Scholarship

Many developmental, physiological, and behavioral processes depend on the precise expression of genes in space and time. Such spatiotemporal gene expression phenotypes arise from the binding of sequence-specific transcription factors (TFs) to DNA, and from the regulation of nearby genes that such binding causes. These nearby genes may themselves encode TFs, giving rise to a transcription factor network (TFN), wherein nodes represent TFs and directed edges denote regulatory interactions between TFs. Computational studies have linked several topological properties of TFNs - such as their degree distribution - with the robustness of a TFN's gene expression phenotype to genetic and environmental …

Discovery And Elucidation Of The Fgfr3-Tacc3 Recurrent Fusion In Glioblastoma, Brittany C. Parker Kerrigan

Dissertations and Theses (Open Access)

Fusion genes occur due to chromosomal instability where two previously separate genes rearrange and fuse together, forming a hybrid gene. The first fusions were reported in leukemias; however, with the advent of more powerful sequencing technologies, fusions have recently been reported in several solid tumors. Using next-generation deep sequencing approaches, we discovered a fusion gene connecting the fibroblast growth factor receptor 3 (FGFR3) gene to the transforming coiled-coil containing protein 3 (TACC3) gene in glioblastoma multiforme. The fusion occurred in 8.3% of patient samples, but not in low grade or normal samples. FGFR3-TACC3 produced an in-frame …

Wonders Of Wisconsin: A Study On Insect Macrophotography, Brenna L. Decker

Lawrence University Honors Projects

This past year I have been honing my skills as an entomologist and as a photographer. My solo exhibition “Wonders of Wisconsin: A Study on Insect Macrophotography” not only presents my personal progress, but also represents an overarching theme of a liberal arts education: connectivity. Everything we see or learn on campus and throughout life is connected. This audience-engaging exhibition has provided a visual for the connections between the fields of science and studio art, the art movements of New Objectivity and Relational Aesthetics, and between human and insect life.

The final exhibition opening on May 1^st at 5:30pm …

Molecular Dynamics Simulations As A Characterization Method Of Biologically Relevant Segments Of Dna, Carman Polsinelli

Senior Honors Projects

Biologically relevant short sequences of DNA have previously been shown to possess high affinity and specificity for binding of small polyamide structures to their minor groove. These structures, or minor groove binders, have the potential to control access to specific regulatory regions of DNA. Before modeling the binding of these polyamides to the DNA, the small segments of DNA must be characterized for better understanding of the impact the minor groove binder will have on the structure of the DNA. The method for such a characterization is a molecular dynamics computer simulation including the solvent effects for a length of …

Sexual Dimorphism Of Staminate- And Pistillate-Phase Flowers Of Saponaria Officinalis (Bouncing Bet) Affects Pollinator Behavior And Seed Set, Dana A. Dudle, Leah M. Freestone, Peter Konieczny, Michael B. Tobin, Michael M. Britton

Biology Faculty publications

The sequential separation of male and female function in flowers of dichogamous species allows for the evolution of differing morphologies that maximize fitness through seed siring and seed set. We examined staminate- and pistillate-phase flowers of protandrous Saponaria officinalis for dimorphism in floral traits and their effects on pollinator attraction and seed set. Pistillate-phase flowers have larger petals, greater mass, and are pinker in color, but due to a shape change, pistillate-phase flowers have smaller corolla diameters than staminate-phase flowers. There was no difference in nectar volume or sugar content one day after anthesis, and minimal evidence for UV nectar …

Extracts Of Trichostema Lanatum Inhibit The Growth Of Gram-Positive Bacteria And An Escherichia Coli Δtolc Mutant Strain, Matthew C. Fleming

Seaver College Research And Scholarly Achievement Symposium

The Chumash Native Americans of Southern California have well-documented traditions of using plants for medicinal purposes. If a specific plant has traditionally been used for the treatment of cuts, wounds and infections, it may contain chemicals with anti-bacterial properties. One plant that fits these criteria is Trichostema lanatum (woolly blue curls). We tested extracts of T. lanatum for their ability to inhibit the growth of a variety of bacteria. Because of the widespread use of antibiotics over the past sixty years bacteria are evolving greater resistance to known antibiotics, but unfortunately the rate of antibiotic discovery has diminished during the …

Cardiovascular Health Among Us And Argentine University Students: A Comparative Study Of Behaviors And Risk Factors, Gina Fitzgerald, Gabriella Smith

Seaver College Research And Scholarly Achievement Symposium

Cardiovascular disease for some time has been the leading cause of death in the Western world. Primary prevention is the only way to halt the onset of cardiovascular disease, yet there is little information on the prevalence of risk factors for cardiovascular disease in young adults. This study seeks to evaluate students from the Catholic University of Argentina and Pepperdine University of America for the prevalence of CVD risk factors, as well as knowledge of CVD and daily habits that contribute to heart health. Thus we compared two cultures with very different lifestyles and prevalence of risk factors. We hypothesized …

The Effect Of Shear Stress, Potassium, And Adenosine On Α-1 Adrenergic Vasoconstriction Of Rat Soleus Feed Arteries, Tanner J. Heckle

Seaver College Research And Scholarly Achievement Symposium

During exercise, sympathetic nerve activity increases, augmenting the release of the neurotransmitter norepinephrine (NE) at the arterial wall and into the blood. NE binds to arterial adrenergic receptors to cause vasoconstriction, yet arteries in contracting skeletal muscle dilate during exercise. Previous evidence from Ives et al. suggests that heat and acidosis may partially inhibit constriction resulting from α-1 adrenergic receptors (termed sympatholysis). Our lab has previously demonstrated that rat soleus feed arteries respond to sympathetic signaling solely by α-1 adrenoceptors. We hypothesized that increased levels of arterial wall shear stress, potassium, or adenosine also contribute to sympatholysis, thereby reducing sympathetic …

Influence Of Temperature On The Tensile Strength Of Spider Silk (Araneus Gemmoides), Victoria Lekson

Seaver College Research And Scholarly Achievement Symposium

Temperature ranges between day and night in southern California can be as great as 30°C and may influence vital functioning of ectothermic organisms. Arachnids produce silks from a pair of spinnerets in their abdomen and rely on variance in protein composition to make different types of silks. Temperature may influence tensile strength of filaments. We tested the effects of temperature on tensile strength of dragline silk of five specimens of Araneus gemmoides (orb-weaver) which were collected from Malibu Creek State Park in the Santa Monica Mountains of southern California, under five temperature conditions. Each specimen was placed in a 0.0283 …

Nanoparticle Exposure Activates An Inositol Triphosphate Receptor-Dependent Elevation Of Reactive Oxygen Species And Apoptosis In Human Alveolar Lung Cells, Briana Manes, Sarah Alvarado

Seaver College Research And Scholarly Achievement Symposium

The signaling of cell stress in response to organelle dysfunction, toxin exposure, and mutation is complex; generating responses that can include adaptation, or in severe cases, cellular apoptosis. Nanoparticles (20-100 nm diameter) have been shown to induce cell stress in lung cells, potentially identifying a cause of lung disease in areas with high levels of particulate-based air pollution. This study examines the effect of carbon black (CB) and titanium dioxide (TiO2) nanoparticles on stress signaling and apoptosis in cultured A549 human alveolar epithelial cells. CB and TiO2 powders were dispersed throughout a buffered solution containing bovine serum albumin using probe …

Engaging Non-Scientists In Stem Through Problem-Based Learning And Service Learning, Andrew Tawfik, Rebecca J. Trueman, Matthew M. Lorz

Interdisciplinary Journal of Problem-Based Learning

This study follows the evolution of a single biology course designed for non-science majors. In its original design, the course used only traditional pedagogical techniques, such as lecture and textbook homework assignments. Over several iterations of the course, the class combined problem-based learning (PBL) and service learning to better support student knowledge. For this study, our goal was for students to learn biology concepts as they engaged in a lake cleanup project within the greater Chicago metropolitan area. Data sources consisted of pretest, posttest, and final exam scores to assess learning. The results suggest the combination of PBL and service …

Direct-To-Consumer Genetic Testing In The College Classroom: Knowledge, Attitudes, And Concerns Of Introductory Biology Students, Nicanor Austriaco

Biology Faculty Publications

Pioneered by companies like 23andMe.com, deCODEme.com, and Navigenics.com, direct-to-consumer genetic testing refers to genetic tests that are marketed directly to consumers via television, print media, or the Internet. This kind of testing provides access to a customer’s genetic information without necessarily involving either a medical health care professional or a genetic counselor in the process. In recent years, a course offered to medical and graduate students at Stanford University has included an option for students to undergo personal genotyping, raising the possibility that direct-to-consumer genetic testing could also be incorporated into undergraduate biology courses to enhance student learning. In this …

Deletion Of Aif1 But Not Of Yca1/Mca1 Protects Saccharomyces Cerevisiae And Candida Albicans Cells From Caspofungin-Induced Programmed Cell Death, Nicanor Austriaco, Christopher Chin, Faith Donaghey, Kathrine Helming, Morgan Mccarthy, Stephen Rogers

Biology Faculty Publications

Caspofungin was the first member of a new class of antifungals called echinocandins to be approved by a drug regulatory authority. Like the other echinocandins, caspofungin blocks the synthesis of β(1,3)-D-glucan of the fungal cell wall by inhibiting the enzyme, β(1,3)-D-glucan synthase. Loss of β(1,3)-D-glucan leads to osmotic instability and cell death. However, the precise mechanism of cell death associated with the cytotoxicity of caspofungin was unclear. We now provide evidence that Saccharomyces cerevisiae cells cultured in media containing caspofungin manifest the classical hallmarks of programmed cell death (PCD) in yeast, including the generation of reactive oxygen species (ROS), the …

Tribute To Tinbergen: The Place Of Animal Behavior In Biology, Joan E. Strassmann

Biology Faculty Research

Tinbergen is famous for emphasizing behavioral fieldwork and experimentation under natural circumstances, for founding the field of ethology, for getting a Nobel Prize, and for mentoring Richard Dawkins. He is known for dividing behavior studies into physiology, development, natural selection, and evolutionary history. In the decades since Tinbergen was active, some of the best research in animal behavior fuses Tinbergen's questions, connecting genes to behavioral phenotypes, for example. Behavior is the most synthetic of the life sciences, because observing the actions of an organism can tell us what all those physical and physiological traits are for. Insights from behavior tell …

Conformational Regulation Of Membrane Localization And Activation Of Talin, Pallavi Dwivedi

ETD Archive

Talin is a cytosolic protein which is known to be one of the key players involved in integrin mediated cell adhesion dependent processes, including blood coagulation, and tissue remodeling. It connects the extracellular matrix with the actin cytoskeleton. Talin comprises of a head domain (talin-H) and a rod domain (talin-R). Talin-H is further subdivided in F0, F1, F2 and F3 domains. Talin-R contains 13 contiguous helical bundle domains (R1-R13) followed by an actin binding dimerization domain (DD). The F3 domain contains a key integrin binding site that regulates integrin activation. In our previous studies, we have shown that cytosolic talin …

Airborne Staphylococcus Aureus In The Biology Labs At Southern Adventist University, Harrison Filler

Capstone Research Projects

Staphylococcus aureus has been of growing interest to the scientific community in recent years. It is not only easily transferred from one person to another, but its rapidly evolving antibiotic resistance has made it increasingly difficult to treat. Once thought to be a hospital-acquired disease, S. aureus is now often found in the community. Studies indicate that people and clothing can act as carriers of S. aureus not only directly, but through airborne particles. For these reasons a research experiment was designed to determine the prevalence of S. aureus in the microbiology lab and anatomy and physiology lab at Southern …

Lifelines Winter 2014, Southern Adventist University

Lifelines - Biology Department Newsletter

The Winter 2014 issue of Lifelines contains articles on a dinosaur dig in Wyoming, student missions to Lebanon, an alumni feature, undergraduate research, and a pictorial directory of 2014 biology and allied health graduates.

A Selected Surveyo F Ocean Acidifcation's Effect On Coccolithophore And Other Marine Ecosystems, Taylor Zaw, Joel Wood, Anthony Gonzalez

Featured Research

With it's rapid rate of generation, the coccolithophore was expected to adapt to the altered pH levels relatively quickly. By analyzing several scientific studies concerning this algae's interaction with various water qualities, the species' response is clarified. These findings are compared to rudimentary data concerning pH levels taken along the coast of Malibu.

Leaf Foliar Absorption In Pentagramma Triangularis And Polypodium Californicum, Justin Choe, Carlos Larios, William Prorok, Emily Rose Pierce

Featured Research

In Riparian and moist zones of the Santa Monica Mountains of Southern California, ferns flourish. However, the Mediterranean climate they live in is subject to drought, and the area is currently facing the worst drought it has ever seen. With little moisture in the ground and streams drying up, these ferns are running out of sources of water. However, being on the coast, the area is subject to fog nightly. This research was done to see if ferns can do leaf foliar absorption, getting their water source from the air rather than the ground. We hypothesized that ferns do leaf …

Relating Leaf Temperature On Malosma Laurina To Leaf Proximity From Soil, Brooks O'Hea, Kevin Morgan

Featured Research

The Santa Monica Mountains are home to countless vegetation and plant species, many of which have been forced to adapt to southern California’s stressful environment. With recent droughts and a steady change in climate, an increase in leaf temperature within some species in the Santa Monica Mountains has been observed. One prominent plant found within the mountain range is the malosma laurina, or laurel sumac, the only species of the malosma genus. Malosma laurina is a perfect example of a specie adapting to its stressful environment. Constant brush and shrub fires within the chaparral area where it commonly grows have …

Comparison Of Photosynthetic Ability In Single And Double Palisade Parenchyma Leaves In Southern California, Vincent Quach, Ryan Sauer, Haley Smith, Christian Wright

Featured Research

Melaleuca quinquenervia is a myrtle (family Myrtaceae) with a propensity for invasiveness. The leaves feature an isobilateral orientation: vertically aligned with a layer of palisade parenchyma on both the adaxial and abaxial sides. Quercus agrifolia (Fagaceae) is a native evergreen with one layer of palisade parenchyma. Due to this structural difference, it was hypothesized that Melaleuca would have a higher rate of photosynthesis (Pn) and less reflectance (NDVI) of green light than Quercus. These two variables were compared using an unpaired t-test, yielding p-values of 0.1366 for NDVI and 0.04428 for photosynthetic rate. No significant difference was found between the …

Measuring Water Potential Among Crassula Ovata And Heteromeles Arbutifolia, Monét Mcnally, Stephanie Yakupitiyage, Jamille Lockhart

Featured Research

Chaparral shrubs are known for their abilities to withstand dry environments. Both the California native C3 plant, Heteromeles arbutifolia, also known as Hollywood, and the CAM plant, Crassula ovata, also know as a Jade plant, have the ability to thrive under a Mediterranean-like climate region. However, during severe cases of drought one plant may better adapted than the other. The purpose of this experiment is to determine whether Heteromeles arbutifolia or Crassula ovata is better able to withstand drought by measuring the dehydration rate. We calculated the leaf-area to mass ratio and the change in water potential of each species …

Relationship Between Canopy Location And Tensile Strength Of Leave Of Heteromeles Arbutifolia In Malibu, Ca, Elena Witham, Melinda Marchiano, Danielle Reynolds

Featured Research

Our hypothesis is that canopy location has an effect on the characteristic tensile strength of leaves, with the leaves on the top of the canopy having greater strength than the leaves on the bottom. We tested our experiment by sampling leaves from the top and bottom of three H. arbutifolia specimens, obtaining raw measurements of size, and testing the tensile strength of each leaf using the Instron. We performed t-tests on the data to determine if the average length, width, thickness, and tensile strength were statistically different depending on if our p values were < 0.05 when top and bottom leaves of the same tree were compared. We chose a chapparral stand removed from heavy human traffic and influence, eliminating as many extraneous variables as possible by taking leaves from the same tree of the same age from the same position on the branch and chose three trial specimen of similar height in the same area to reduce the possibility of varying sunlight exposure or water supply from affecting leaf morphology in a way that canopy position would not. The results show that blade length between top and bottom is statistically significantly different, while blade thickness and lateral strength at midsection were not statistically different. From our analysis of the data, it is clear that leaves on the bottom of the plant were longer and broader than leaves on the top, but we determined that canopy location does not have a major effect on tensile strength or thickness, supporting a null hypothesis.

Relationship Between Canopy Location And Tensile Strength Of Leaves Of Heteromeles Arbutifolia In Malibu, Ca, Elena Witham, Melinda Marchiano, Danielle Reynolds

Featured Research

Our hypothesis is that canopy location has an effect on the characteristic tensile strength of leaves, with the leaves on the top of the canopy having greater strength than the leaves on the bottom. We tested our experiment by sampling leaves from the top and bottom of three H. arbutifolia specimens, obtaining raw measurements of size, and testing the tensile strength of each leaf using the Instron. We performed t-tests on the data to determine if the average length, width, thickness, and tensile strength were statistically different depending on if our p values were < 0.05 when top and bottom leaves of the same tree were compared. We chose a chapparral stand removed from heavy human traffic and influence, eliminating as many extraneous variables as possible by taking leaves from the same tree of the same age from the same position on the branch and chose three trial specimen of similar height in the same area to reduce the possibility of varying sunlight exposure or water supply from affecting leaf morphology in a way that canopy position would not. The results show that blade length between top and bottom is statistically significantly different, while blade thickness and lateral strength at midsection were not statistically different. From our analysis of the data, it is clear that leaves on the bottom of the plant were longer and broader than leaves on the top, but we determined that canopy location does not have a major effect on tensile strength or thickness, supporting a null hypothesis.

Correlation Between Freezing Sites And Xylem Vessel Diameter For Three Chaparral Species Of The Santa Monica Mountains, Kaitlyn E. Sauer, Theodora V. Ordog, Nicole A.P.M.K.O.M. Nakamatsu

Featured Research

Coastal exposures of the Santa Monica Mountains rarely experience freezing temperatures

(0 °C) because of the ameliorating effects of the Pacific Ocean and seawater’s specific heat capacity. In contrast, inland sites of the Santa Monica Mountains frequently experience winter temperatures below -10 °C. This temperature gradient, from coast to inland, may be a major determinate of species distribution patterns. To investigate possible mechanisms by which freezing impacts chaparral distribution patterns, we examined xylem vessel diameter and vessel length of three chaparral species growing at inland freezing sites versus coastal nonfreezing sites (Malosma laurina, Umbellularia californica, and Ceanothus megacarpus). It has …

Measuring Photosynthesis To Evaluate Photoprotection By Anthocyanins In Malosma Laurina, Jorge Bojorkez-Calderon, Hannah Imson

Featured Research

The purpose of this investigation was to observe the differences between the photosynthetic rates and photo-protection of young, red, juvenile leaves of Malosma laurina, and compare it to young, green leaves. To accomplish this, the open-system of Li-6400 XT was brought out into the field to a shrub of Malosma laurina that was flourishing and had both red and green leaves present. Then, data of fluorescence, photosynthetic rate, and conductance was taken from both red leaves and green leaves, and the photosynthetic rates were compared. Through this investigation, we were able to quantify that in young, red leaves, which had …

The Effects Of Higher And Lower Co2 Levels In The Atmosphere On The Photosynthetic Rates And Stomatal Conductance Of Malosma Laurina In The Santa Monica Mountains, Victoria A. Thorsen, Maverick E. Turner, Colby P. Harriman

Featured Research

We hypothesize that higher CO2 levels will lead to a change in photosynthetic performance in the Malosma laurina population of the Santa Monica Mountains. We used one Malosma laurina that is across the street from university’s theme tower. We chose this specific plant because it was in the sun and it was in a well irrigated area. We selected a plant that is in non-shaded areas at 12:00 pm and then dark adapt them for 20 minutes. We selected an adult plant that was between four and six feet tall. We took the measurements from the upper leaves of the …

Relationship Between Dehydration Tolerance Of California Ferns And The Mechanical Strength Of Their Stipes, Helen I. Holmlund, Jarmila Pitterman, Stephen D. Davis

Featured Research

In vascular plants, water moves upwards through xylem vessels/tracheids due to negative pressures created by the evaporative pull of water. Under severe dehydrated, extreme negative pressures are known to cause xylem cavitation and embolism. In seed-bearing plants, the mechanical support of stem xylem has been shown to be a good predictor of cavitation resistance, presumably because sclerenchyma fibers buttress against micro-fracture or collapse of conduit walls. In spore-bearing plants, such as ferns, current anatomical theory indicates that mechanical support lies external to underlying xylem, in the outer hypodermal region, leaving the central xylem in ferns without any fiber support. In …