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2013

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Articles 511 - 540 of 1508

Full-Text Articles in Biology

Decades-Long Social Memory In Bottlenose Dolphins, Jason N. Bruck Jul 2013

Decades-Long Social Memory In Bottlenose Dolphins, Jason N. Bruck

Faculty Publications

Long-term social memory is important, because it is an ecologically relevant test of cognitive capacity, it helps us understand which social relationships are remembered and it relates two seemingly disparate disciplines: cognition and sociality. For dolphins, long-term memory for conspecifics could help assess social threats as well as potential social or hunting alliances in a very fluid and complex fission-fusion social system, yet we have no idea how long dolphins can remember each other. Through a playback study conducted within a multi-institution dolphin breeding consortium (where animals are moved between different facilities), recognition of unfamiliar versus familiar signature whistles of …

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Evaluating Itpr-Dependence Of Apoptotic Signaling From The Endoplasmic Reticulum, Agustin Vargas, Jay L. Brewster Jul 2013

Evaluating Itpr-Dependence Of Apoptotic Signaling From The Endoplasmic Reticulum, Agustin Vargas, Jay L. Brewster

Featured Research

Stress within the endoplasmic reticulum (ER) can be induced by misfolded proteins accumulating in the lumen of this organelle. Signaling of ER stress to other parts of the cell results in altered gene expression, physiological adaptation, and with sustained stress, apoptosis (cell suicide). ER stress is often studied with highly toxic compounds that create severe ER stress rapidly, and a condition that is likely not physiologically relevant within an organism. In this study, we examine the apoptotic signaling induced by moderate ER stress, and in particular the inositol 1,4,5-trisphosphate receptor (ITPR). The ITPR regulates Ca2+ release from the ER lumen, …

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Lysophosphatidic Acid Stimulates Lymphangiogenesis In Human Lymphatic Endothelial Cells, John Macbeth, Donna Nofziger-Plank Jul 2013

Lysophosphatidic Acid Stimulates Lymphangiogenesis In Human Lymphatic Endothelial Cells, John Macbeth, Donna Nofziger-Plank

Featured Research

Lymphangiogenesis is the process by which new lymphatic vessels sprout and grow from existing vessels whether under developmental, immunological, or cancerous conditions. Proper lymphatic vessel formation is important in working alongside normal angiogenesis in order to help regulate the body’s tissue fluid as well as aid in immunosurveillance. Various factors regulate lymphangiogenesis such as members of the vascular endothelial growth factor family (VEGF). Another factor that has recently been identified to play a role in lymphangiogenesis is the bio-active phospholipid lysophosphatidic acid (LPA) however the molecular mechanism by which LPA regulates lymphangiogenesis has not been well characterized. In this study, …

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An Ethnobotanical Approach To Finding Antimicrobial Compounds In Wooly Blue Curls (Trichostema Lanatum) Using A Kirby-Bauer Disc Diffusion Assay, Matthew C. Fleming, P. Matthew Joyner Jul 2013

An Ethnobotanical Approach To Finding Antimicrobial Compounds In Wooly Blue Curls (Trichostema Lanatum) Using A Kirby-Bauer Disc Diffusion Assay, Matthew C. Fleming, P. Matthew Joyner

Featured Research

Plants can be an important source of creativity and production of new drugs. In this study, extracts of wooly blue curls (Trichostema lanatum) were made using DMSO and tested for antimicrobial activity on a panel of bacteria commonly found in separate ecological niches. Wooly blue curls (WBC) was chosen due to its being recorded as a strong disinfectant by the Chumash people. It was found that WBC does exhibit antimicrobial activity against gram positive bacteria and not against gram negative bacteria. However, gram negative bacteria with reduced drug efflux function became susceptible to the WBC extract.

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Carbon Black And Titanium Dioxide Nanoparticles Differentially Activate Oxidative Stress And Apoptosis In A549 Human Alveolar Epithelial Cells, Sarah Alvarado, Brianna Manes, Jay L. Brewster Jul 2013

Carbon Black And Titanium Dioxide Nanoparticles Differentially Activate Oxidative Stress And Apoptosis In A549 Human Alveolar Epithelial Cells, Sarah Alvarado, Brianna Manes, Jay L. Brewster

Featured Research

Recent studies have demonstrated that variation between particulate matter compositions have universally adverse effects on cells and living tissues. Carbon black and titanium dioxide are two such particulates that we are continuously exposed to, yet there is limited research to examine the potential deleterious effects on living tissue. The objective of this study is to characterize the effect of carbon black (CB) and titanium dioxide (TiO2) particulates on A549 human alveolar epithelial lung cells. CB and TiO2 powders were dispersed throughout a solution of water and bovine serum albumin by high-powered sonication. The effects of these particulates on A549 cells …

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Starvation-Associated Genome Restructuring Can Lead To Reproductive Isolation In Yeast, Evgueny Kroll, Scott Coyle, Barbara Dunn, Gregory Koniges, Anthony Aragon, Jeremy Edwards, Frank Rosenzweig Jul 2013

Starvation-Associated Genome Restructuring Can Lead To Reproductive Isolation In Yeast, Evgueny Kroll, Scott Coyle, Barbara Dunn, Gregory Koniges, Anthony Aragon, Jeremy Edwards, Frank Rosenzweig

Biological Sciences Faculty Publications

Knowledge of the mechanisms that lead to reproductive isolation is essential for understanding population structure and speciation. While several models have been advanced to explain post-mating reproductive isolation, experimental data supporting most are indirect. Laboratory investigations of this phenomenon are typically carried out under benign conditions, which result in low rates of genetic change unlikely to initiate reproductive isolation. Previously, we described an experimental system using the yeast Saccharomyces cerevisiae where starvation served as a proxy to any stress that decreases reproduction and/or survivorship. We showed that novel lineages with restructured genomes quickly emerged in starved populations, and that these …

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Immunomodulatory Activity Of Sambucus Mexicana And Trichostema Lanatum On Lps Stimulated Raw 264.7 Macrophage Cells, Victoria Hester, P. Matthew Joyner Jul 2013

Immunomodulatory Activity Of Sambucus Mexicana And Trichostema Lanatum On Lps Stimulated Raw 264.7 Macrophage Cells, Victoria Hester, P. Matthew Joyner

Featured Research

Chumash medicinal plants Sambucus mexicana (Mexican elderberry) and Trichostema lanatum (woolly blue curls) were tested for immunomodulatory activity. Anti-inflammatory effects were determined by treating LPS induced RAW 264.7 macrophage cells with plant extracts and measuring the levels of cytokines: tumor necrosis factor alpha (TNF-alpha) and interleukin 10 (IL-10). We hypothesized that both plants would exert immunomodulatory activity by reducing the pro-inflammatory production of TNF-alpha or by promoting M2 polarization with a concurrent increase in IL-10 production. At concentration 0.01 mg/mL woolly blue curls and Mexican elderberry demonstrated anti-inflammatory activity by reducing the concentration of TNF-alpha in vitro, while levels of …

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The Survivin And Ciap1 Anti-Apoptotic Proteins Are Differentially Downregulated In Response To Endoplasmic Reticulum Stress, Vicki Mercado, Jay L. Brewster Jul 2013

The Survivin And Ciap1 Anti-Apoptotic Proteins Are Differentially Downregulated In Response To Endoplasmic Reticulum Stress, Vicki Mercado, Jay L. Brewster

Featured Research

The endoplasmic reticulum (ER) is an organelle tasked with synthesis and transport of 50% of new cellular proteins. Dysfunction within this organelle creates signals for repair, adaptation, and in severe cases, cellular apoptosis. Multiple human diseases have been associated with ER dysfunction, and the activation of apoptosis in important populations of cells. Inhibitor of Apoptosis (IAP) proteins are cytosolic proteins that play an anti-apoptotic role in the cytosol. The relationship between endoplasmic reticulum (ER) stress and the expression/stability of IAPs is not well characterized. The objective of this study was to characterize the affect of ER stress on the expression/stability …

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The Regulatory Effect Of Semaphorin 7a On Proliferation And Migration In Human Umbilical Vein Endothelial Cells, Steven R. Flemming, Donna Nofziger-Plank Jul 2013

The Regulatory Effect Of Semaphorin 7a On Proliferation And Migration In Human Umbilical Vein Endothelial Cells, Steven R. Flemming, Donna Nofziger-Plank

Featured Research

Semaphorin 7A (SEMA 7A), a factor originally identified as regulating axon growth, has recently been implicated as a pro-angiogenic factor. The molecular mechanisms for this ability to stimulate angiogenesis have not been identified. This study examines if SEMA 7A can have a direct effect on vascular endothelial cells or whether it indirectly induces angiogenesis through stimulation and recruitment of macrophages as has been suggested. Using a human umbilical vein endothelial cells (HUVECs), the ability of SEMA 7A to affect proliferation and migration was examined. HUVECs were exposed to SEMA 7A directly or to conditioned media collected from macrophages exposed to …

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Effect Of Shear Stress On Ecnos Expression And Dilation In Soleus Feed Arteries, Blanca Perez, Jay L. Brewster, Jeffrey Jasperse Jul 2013

Effect Of Shear Stress On Ecnos Expression And Dilation In Soleus Feed Arteries, Blanca Perez, Jay L. Brewster, Jeffrey Jasperse

Featured Research

Shear stress causes artery dilation and increased expression of endothelial cell nitric oxide synthase (ecNOS) in coronary and placental arteries. We sought to determine the importance of shear stress in maintaining normal dilation and normal levels of ecNOS in rat soleus feed arteries (SFA). SFA were isolated from male Sprague-Dawley rats and cannulated for in vitro microscopy (Fig. 6). SFA were exposed to no shear stress, low shear stress, or high shear stress conditions for 4 hours. After 4 hours, endothelium-dependent dilation (acetylcholine: ACh) and endothelium-independent dilation (sodium nitroprusside: SNP) were tested. Arteries were then uncannulated, mRNA was isolated, and …

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The Effect Of Shear Stress, Potassium, And Adenosine On Α-1 Adrenergic Vasoconstriction Of Rat Soleus Feed Arteries, Tanner J. Heckle, Jeffrey Jasperse Jul 2013

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

Featured Research

During exercise, blood flow increases to the working skeletal muscle primarily because of dilation of the arteries and arterioles feeding the muscle. Sympathetic nerve activity also increases during exercise, augmenting the release of the neurotransmitter norepinephrine (NE) at the arterial wall and into the blood. NE acts to constrict blood vessels; however, arteries and arterioles within contracting skeletal muscle dilate despite the increased NE present. This has led to the concept of functional sympatholysis (4), the idea that a chemical released from contracting skeletal muscle interferes with NE signaling. NE acts by binding to adrenergic (alpha and beta) receptors, and …

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Circadian Rhythms In Saccharomyces Cerevisiae, Khyla Rose Alorro, Sean Mcnabney Jul 2013

Circadian Rhythms In Saccharomyces Cerevisiae, Khyla Rose Alorro, Sean Mcnabney

Symposium on Research and Creative Expression (SORCE)

Circadian rhythms are endogenous, time-oriented cycles that cause physical or behavioral changes in organisms. While several studies suggest that such rhythms are ubiquitous for life, recent experiments demonstrate that the regulatory mechanisms behind them differ for each organism. Little is known about the molecular machinery that governs the circadian clock in Saccharomyces cerevisiae, but its output appears to directly influence the enzymes glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and peroxiredoxin. This project centered on linking GAPDH concentrations to various stages of the circadian rhythm in order to inductively determine components of the circadian clock. Spectroscopic assays and Western blots were used to determine …

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Rethinking The Composition Of A Rational Antibiotic Arsenal For The 21st Century, Margaret A. Riley, Sandra M. Robinson, Christopher M. Roy, Robert L. Dorit Jul 2013

Rethinking The Composition Of A Rational Antibiotic Arsenal For The 21st Century, Margaret A. Riley, Sandra M. Robinson, Christopher M. Roy, Robert L. Dorit

Biological Sciences: Faculty Publications

The importance of the human microbiome in health may be the single most valuable development in our conception of the microbial world since Pasteur's germ theory of the 1860s. Its implications for our understanding of health and pathogenesis are profound. Coupled with the revolution in diagnostics that we are now witnessing - a revolution that changes medicine from a science of symptoms to a science of causes - we cannot continue to develop antibiotics as we have for the past 80 years. Instead, we need to usher in a new conception of the role of antibiotics in treatment: away from …

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Role Of Nucleation In Cortical Microtubule Array Organization: Variations On A Theme, Erica A. Fishel, Ram Dixit Jul 2013

Role Of Nucleation In Cortical Microtubule Array Organization: Variations On A Theme, Erica A. Fishel, Ram Dixit

Biology Faculty Research

The interphase cortical microtubules (CMTs) of plant cells form strikingly ordered arrays in the absence of a dedicated microtubule-organizing center. Considerable research effort has focused on activities such as bundling and severing that occur after CMT nucleation and are thought to be important for generating and maintaining ordered arrays. In this review, we focus on how nucleation affects CMT array organization. The bulk of CMTs are initiated from γ-tubulin-containing nucleation complexes localized to the lateral walls of pre-existing CMTs. These CMTs grow either at an acute angle or parallel to the pre-existing CMT. Although the impact of microtubule-dependent nucleation is …

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Analysis Of Synephrine Content In Bitter Orange (Citrus Aurantium L.) Dietary Supplements, Martha L. Newell Jul 2013

Analysis Of Synephrine Content In Bitter Orange (Citrus Aurantium L.) Dietary Supplements, Martha L. Newell

Theses and Dissertations

Many Americans are either currently taking, or have recently taken, non-prescription dietary supplements. These supplements claim to help prevent or relieve any number of ailments, but are not regulated by any governing body. One common use of dietary supplements is to aid in weight loss. Synephrine, the most abundant active component in bitter orange (Citrus aurantium L.) extracts, became a regular ingredient in weight loss supplements after the 2004 ephedra ban. The initial goal of this research was to use reverse phase high performance liquid chromatography (HPLC) to determine the synephrine content of five dietary supplements and compare …

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Increase In Acc Oxidase Levels And Activities During Paradormancy Release Of Leafy Spurge (Euphorbia Esula) Buds, Wun S. Chao, Marcelo Serpe, Jeffrey C. Suttle, Ying Jia Jul 2013

Increase In Acc Oxidase Levels And Activities During Paradormancy Release Of Leafy Spurge (Euphorbia Esula) Buds, Wun S. Chao, Marcelo Serpe, Jeffrey C. Suttle, Ying Jia

Biology Faculty Publications and Presentations

The plant hormone ethylene is known to affect various developmental processes including dormancy and growth. Yet, little information is available about the role of ethylene during paradormancy release in underground adventitious buds of leafy spurge. In this study, we examined changes in ethylene evolution and the ethylene biosynthetic enzyme ACC oxidase following paradormancy release (growth induction). Our results did not show an obvious increase in ethylene during bud growth. However, when buds were incubated with 1 mM ACC, ethylene levels were higher in growing than non-growing buds, suggesting that the levels of ACC oxidase increased in growing buds. Real-time qPCR …

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The Mayfly Newsletter, Peter M. Grant Jul 2013

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.

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Subglacial Lake Vostok (Antarctica) Accretion Ice Contains A Diverse Set Of Sequences From Aquatic, Marine And Sediment-Inhabiting Bacteria And Eukarya, Scott O. Rogers, Yury M. Shtarkman, Zeynep A. Koçer, Robyn Edgar, Ram S. Veerapneni, Tom D'Elia, Paul F. Morris Jul 2013

Subglacial Lake Vostok (Antarctica) Accretion Ice Contains A Diverse Set Of Sequences From Aquatic, Marine And Sediment-Inhabiting Bacteria And Eukarya, Scott O. Rogers, Yury M. Shtarkman, Zeynep A. Koçer, Robyn Edgar, Ram S. Veerapneni, Tom D'Elia, Paul F. Morris

Biological Sciences Faculty Publications

Lake Vostok, the 7th largest (by volume) and 4th deepest lake on Earth, is covered by more than 3,700 m of ice, making it the largest subglacial lake known. The combination of cold, heat (from possible hydrothermal activity), pressure (from the overriding glacier), limited nutrients and complete darkness presents extreme challenges to life. Here, we report metagenomic/metatranscriptomic sequence analyses from four accretion ice sections from the Vostok 5G ice core. Two sections accreted in the vicinity of an embayment on the southwestern end of the lake, and the other two represented part of the southern main basin. We obtained 3,507 …

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Using Economic Instruments To Develop Effective Management Of Invasive Species: Insights From A Bioeconomic Model, Shana M. Mcdermott, Rebecca E. Irwin, Brad W. Taylor Jul 2013

Using Economic Instruments To Develop Effective Management Of Invasive Species: Insights From A Bioeconomic Model, Shana M. Mcdermott, Rebecca E. Irwin, Brad W. Taylor

Dartmouth Scholarship

Economic growth is recognized as an important factor associated with species invasions. Consequently, there is increasing need to develop solutions that combine economics and ecology to inform invasive species management. We developed a model combining economic, ecological, and sociological factors to assess the degree to which economic policies can be used to control invasive plants. Because invasive plants often spread across numerous properties, we explored whether property owners should manage invaders cooperatively as a group by incorporating the negative effects of invader spread in management decisions (collective management) or independently, whereby the negative effects of invasive plant spread are ignored …

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Neurodegeneration In Drop-Dead Mutant Drosophila Melanogaster Is Associated With The Respiratory System But Not With Hypoxia, Christine Lynn Sansone, Edward M. Blumenthal Jul 2013

Neurodegeneration In Drop-Dead Mutant Drosophila Melanogaster Is Associated With The Respiratory System But Not With Hypoxia, Christine Lynn Sansone, Edward M. Blumenthal

Biological Sciences Faculty Research and Publications

Mutations in the gene drop-dead (drd) cause diverse phenotypes in adult Drosophila melanogaster including early lethality, neurodegeneration, tracheal defects, gut dysfunction, reduced body mass, and female sterility. Despite the identification of the drd gene itself, the causes of early lethality and neurodegeneration in the mutant flies remain unknown. To determine the pattern of drd expression associated with the neurodegenerative phenotype, knockdown of drd with various Gal4 drivers was performed. Early adult lethality and neurodegeneration were observed upon knockdown of drd in the tracheal system with two independent insertions of the breathless-Gal4 driver and upon knockdown in the tracheal …

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Nonspecific, Reversible Inhibition Of Voltage-Gated Calcium Channels By Camkii Inhibitor Ck59, Andrew S. Kahrls, Michelle Mynlieff Jul 2013

Nonspecific, Reversible Inhibition Of Voltage-Gated Calcium Channels By Camkii Inhibitor Ck59, Andrew S. Kahrls, Michelle Mynlieff

Biological Sciences Faculty Research and Publications

Investigation of kinase-related processes often uses pharmacological inhibition to reveal pathways in which kinases are involved. However, one concern about using such kinase inhibitors is their potential lack of specificity. Here, we report that the calcium–calmodulin-dependent kinase II (CaMKII) inhibitor CK59 inhibited multiple voltage-gated calcium channels, including the L-type channel during depolarization in a dose-dependent manner. The use of another CaMKII inhibitor, cell-permeable autocamtide-2 related inhibitory peptide II (Ant-AIP-II), failed to similarly decrease calcium current or entry in hippocampal cultures, as shown by ratiometric calcium imaging and whole-cell patch clamp electrophysiology. Notably, inhibition due to CK59 was reversible; washout of …

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Sfmtp1 And Spmtp1 Cloning And Expression In Saccharomyces Cerevisiae: Potential For The Genetic Engineering Of Arabidopsis Thaliana, Elyssa Rae Garza Jul 2013

Sfmtp1 And Spmtp1 Cloning And Expression In Saccharomyces Cerevisiae: Potential For The Genetic Engineering Of Arabidopsis Thaliana, Elyssa Rae Garza

Theses and Dissertations - UTB/UTPA

To evaluate metal tolerance conferred by the overexpression of Metal Tolerance Protein 1 (MTP1) in transgenic non-accumulator plants such as Arabidopsis thaliana, a model system was developed in Saccharomyces cerevisiae containing either SfMTP1 cDNA, from the metal tolerant plant Streptanthus farnsworthianus, or SpMTP1 cDNA, from the hyperaccumulator Streptanthus polygaloides. Nonquantitative RT-PCR showed constitutive expression of MTP1 in both plant species. Alignment of SfMTP1 and SpMTP1 protein sequences shows a gap in SpMTP1 in a variable histidine region known to affect metal transport. Disk assays revealed SfMTP1 cDNA imparted greater Ni tolerance to yeast than SpMTP1 cDNA; however, SpMTP1 showed higher …

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Residential Edges As Ecological Traps: Postfledgling Survival Of A Ground-Nesting Passerine In A Forested Urban Park, Amy A. Shipley, Michael T. Murphy, Adam H. Elzinga Jul 2013

Residential Edges As Ecological Traps: Postfledgling Survival Of A Ground-Nesting Passerine In A Forested Urban Park, Amy A. Shipley, Michael T. Murphy, Adam H. Elzinga

Biology Faculty Publications and Presentations

Substantial offspring mortality can occur during the postfledging period of birds, but few postfledging survival studies have been conducted within the context of habitat suitability. We conducted a 2-year radiotelemetry study of Spotted Towhee (Pipilo maculatus) reproductive success and fledgling survival in a 24-ha forested park in a residential area of Lake Oswego, Oregon. In corroboration of previous research on this species, we found (1) that Spotted Towhees nested closer to the edge between the park and residential neighborhoods than expected by chance, and (2) that pairs nesting near edges produced the largest and most offspring. However, fates were reversed …

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Mhc And Mate Choice In Anolis Sagrei, Angela S. Hung Jul 2013

Mhc And Mate Choice In Anolis Sagrei, Angela S. Hung

Biology ETDs

The study of sexual selection saw its intrepid inception when Charles Darwin observed the earnest with which many male birds must court a female before she will, but often not, mate with him. His idea of the choosy female' was a radical one in the Victorian era when women were regarded as the 'passive sex. In the century and a half that followed, sexual selection driven by female choice is now widely accepted and strongly supported. Today, with emerging technologies, the nuances and complexities of sexual reproductive are finally coming to light. Female choice in two species is described here. …

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Scaling Of Crop Diversity And Optimal Allocation Of Foodshed Infrastructure, Michael Chang Jul 2013

Scaling Of Crop Diversity And Optimal Allocation Of Foodshed Infrastructure, Michael Chang

Biology ETDs

Food hubs are organizations that manage the aggregation and distribution of local products, and are a small, but growing means to satisfy high demand for diverse, healthy diets. However, economic barriers inhibit small producers and distributors from developing mainstream, local consumer alternatives to industrial-scale products. To build foodshed, distribution hubs could help overcome these challenges by reducing costs through shared refrigeration, processing, and transportation infrastructure. However, there is no theory to help plan them. I present and test theory to allocate foodshed infrastructure based on insight by Dunn, et al. (2011) that Shannon diversity measured relative to a whole set …

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The Effects Of Climate Change On Stream Invertebrates In Their Role As Biological Indicators And Responders To Disturbance, Anna T. Hamilton Jul 2013

The Effects Of Climate Change On Stream Invertebrates In Their Role As Biological Indicators And Responders To Disturbance, Anna T. Hamilton

Biology ETDs

Global climate models provide estimates of future changes in air temperature and precipitation patterns, drought, flooding, sea-level rise, and increases in the frequency, duration, and intensity of extreme heat and storm events. These climate changes will affect stream invertebrate communities directly, indirectly, and through interactions with other stressors, resulting in a range of biological responses, including species range shifts, losses and replacements, novel community compositions, and altered ecosystem functions and services. Effects will vary regionally and present heretofore unaccounted influences on biomonitoring, which water-quality agencies use to assess the status and health of ecosystems as required by the Clean Water …

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Sympatric Speciation Is Reinforced By Predation, Parasite Load, Reproductive Character Displacement, And Sexual Selection In Two Species Flocks Of Pupfish (Cyprinodon Spp), Rhiannon J. D. West Jul 2013

Sympatric Speciation Is Reinforced By Predation, Parasite Load, Reproductive Character Displacement, And Sexual Selection In Two Species Flocks Of Pupfish (Cyprinodon Spp), Rhiannon J. D. West

Biology ETDs

Sympatric speciation, the divergence of one lineage into two or more lineages within one geographic range, is often driven by disruptive selection on niche utilization. While niche specialization is found in sympatrically speciated groups, it is often reinforced by other strong selective pressure. This dissertation examines the role of predation, morphology, mate choice, and parasite load in maintaining reproductive isolation in two sympatrically speciated species flocks of pupfish (Cyprinodon). The role that predation, morphology and male and female mate choice play in reproductive isolation is examined in the Bahamian species flock. To examine the role of predation, we focus on …

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Examining New Phylogenetic Markers To Uncover The Evolutionary History Of Early-Diverging Fungi: Comparing Mcm7, Tsr1 And Rrna Genes For Single- And Multi-Gene Analyses Of The Kickxellomycotina, Eric D. Tretter, E. M. Johnson, Yan Wang, Prasanna Kandel, Merlin M. White Jun 2013

Examining New Phylogenetic Markers To Uncover The Evolutionary History Of Early-Diverging Fungi: Comparing Mcm7, Tsr1 And Rrna Genes For Single- And Multi-Gene Analyses Of The Kickxellomycotina, Eric D. Tretter, E. M. Johnson, Yan Wang, Prasanna Kandel, Merlin M. White

Biology Faculty Publications and Presentations

The recently recognised protein-coding genes MCM7 and TSR1 have shown significant promise for phylogenetic resolution within the Ascomycota and Basidiomycota, but have remained unexamined within other fungal groups (except for Mucorales). We designed and tested primers to amplify these genes across early-diverging fungal clades, with emphasis on the Kickxellomycotina, zygomycetous fungi with characteristic flared septal walls forming pores with lenticular plugs. Phylogenetic tree resolution and congruence with MCM7 and TSR1 were compared against those inferred with nuclear small (SSU) and large subunit (LSU) rRNA genes. We also combined MCM7 and TSR1 data with the rDNA data to …

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Penggunaan Pita Melalui Pembelajaran Missouri Mathematics Project Untuk Memahamkan Siswa Tentang Luas Permukaan Bola, Pentri Arfia Dewi Jun 2013

Penggunaan Pita Melalui Pembelajaran Missouri Mathematics Project Untuk Memahamkan Siswa Tentang Luas Permukaan Bola, Pentri Arfia Dewi

Jurnal Pendidikan Sains

Penelitian ini akan mendeskripsikan penggunaan pita melalui pembelajaran Missouri Mathematics Project untuk memahamkan siswa tentang luas permukaan bola. Pembelajaran yang dilaksanakan berdasarkan pada tahapan pembelajaran Missouri Mathematics Project yang dipadukan dengan bahan manipulatif. Penelitian ini merupakan penelitian tindakan kelas. Setiap siklus terdiri dari tiga kali pertemuan. Dalam penelitian ini juga dilakukan kajian dari jawaban siswa. Hasil penelitian ini menunjukkan bahwa penerapan pembelajaran menggunakan bahan manipulatif bola dan pita dapat memahamkan siswa tentang luas permukaan bola.

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Pembelajaran Berbantuan Multimedia Berdasarkan Teori Beban Kognitif Untuk Meningkatkan Kemampuan Menyelesaikan Masalah Program Linear Siswa X Tkr 1 Smkn 1 Doko, Fifi Damayanti Jun 2013

Pembelajaran Berbantuan Multimedia Berdasarkan Teori Beban Kognitif Untuk Meningkatkan Kemampuan Menyelesaikan Masalah Program Linear Siswa X Tkr 1 Smkn 1 Doko, Fifi Damayanti

Jurnal Pendidikan Sains

Berdasarkan teori beban kognitif, pembelajaran efektif terjadi apabila beban intrinsic dikelola dengan baik, beban germane ditingkatkan, dan beban extraneous dikurangi. Penerapan multimedia merupakan salah satu upaya untuk mencapai pembelajaran yang efektif. Penelitian ini mengkaji penerapan pembelajaran matematika berbantuan multimedia dalam meningkatkan kemampuan siswa menyelesaikan masalah program linear. Penelitian ini menggunakan pendekatan penelitian tindakan kelas yang dilaksanakan dalam dua siklus. Hasil penelitian menunjukkan bahwa penggunaan multimedia dapat mengelola beban intrinsic, meningkatkan beban germane, dan mengurangi beban extraneous, sehingga kemampuan siswa dalam menyelesaikan masalah program linear meningkat.

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