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Full-Text Articles in Life Sciences

Irruptive Migration Of Chestnut-Backed Chickadees To Southwestern Idaho, Jay D. Carlisle Jan 2012

Irruptive Migration Of Chestnut-Backed Chickadees To Southwestern Idaho, Jay D. Carlisle

Intermountain Bird Observatory Publications and Presentations

I document irruptive movements of the Chestnut-backed Chickadee to Lucky Peak in southwestern Idaho, over 80 km from its regular range. Chestnut-backed Chickadees were captured and/or observed at Lucky Peak in 2000, 2004, and 2008. To evaluate the context for this phenomenon, I also examined data on capture of all chickadees and other irruptive species at Lucky Peak and numbers of irruptive species recorded on Idaho Christmas Bird Counts (CBC) from 1997 to 2011. Though CBCs in the winter of 2004–05 (following the largest movement of Chestnut-backed Chickadees at Lucky Peak in fall 2004) found high numbers of many irruptive …


In Depth Analysis Of An Anterior Cruciate Ligament Tear: Effects On The Mind And Body, Keimi Lew Jan 2012

In Depth Analysis Of An Anterior Cruciate Ligament Tear: Effects On The Mind And Body, Keimi Lew

Whittier Scholars Program

Injuries have always been a major concern for athletes; anterior cruciate ligament (ACL) injuries are among the most common serious injuries around. With the increase in reported ACL injuries, this has become a sort of epidemic especially among female athletes. Female athletes are three times more likely to experience a knee injury than a male athlete competing in the same sport. Since this increase in the last decade, researchers have developed several different hypotheses as to why females are more likely to experience these injuries. With these injuries there is a physical aspect, however, it is much more than that, …


Multi-Partner Interactions In Corals In The Face Of Climate Change, Koty H. Sharp, Kim B. Ritchie Jan 2012

Multi-Partner Interactions In Corals In The Face Of Climate Change, Koty H. Sharp, Kim B. Ritchie

Arts & Sciences Faculty Publications

Recent research has explored the possibility that increased sea-surface temperatures and decreasing pH (ocean acidification) contribute to the ongoing decline of coral reef ecosystems. Within corals, a diverse microbiome exerts significant influence on biogeochemical and ecological processes, including food webs, organismal life cycles, and chemical and nutrient cycling. Microbes on coral reefs play a critical role in regulating larval recruitment, bacterial colonization, and pathogen abundance under ambient conditions, ultimately governing the overall resilience of coral reef systems. As a result, microbial processes may be involved in reef ecosystem-level responses to climate change. Developments of new molecular technologies, in addition to …


2b: "Copy Of Carbon Dioxide Data Illinois Natural Gas", U.S. Energy Information Administration Jan 2012

2b: "Copy Of Carbon Dioxide Data Illinois Natural Gas", U.S. Energy Information Administration

Ecosystem Disruption & Climate Change

No abstract provided.


2b: "Copy Of Carbon Dioxide Data Illinois Totals", U.S. Energy Information Administration Jan 2012

2b: "Copy Of Carbon Dioxide Data Illinois Totals", U.S. Energy Information Administration

Ecosystem Disruption & Climate Change

No abstract provided.


2b: "Copy Of Carbon Dioxide Data Illinois Petroleum Products", U.S. Energy Information Administration Jan 2012

2b: "Copy Of Carbon Dioxide Data Illinois Petroleum Products", U.S. Energy Information Administration

Ecosystem Disruption & Climate Change

No abstract provided.


Cancer And You, Diah-Aldeen Judeh Jan 2012

Cancer And You, Diah-Aldeen Judeh

A with Honors Projects

This project discusses ways a person can identify cancer and what to do if cancer is present.


2b: "Copy Of Carbon Dioxide Data Illinois Coal", U.S. Energy Information Administration Jan 2012

2b: "Copy Of Carbon Dioxide Data Illinois Coal", U.S. Energy Information Administration

Ecosystem Disruption & Climate Change

No abstract provided.


Lifelines Winter 2012, Southern Adventist University Jan 2012

Lifelines Winter 2012, Southern Adventist University

Lifelines - Biology Department Newsletter

The Winter 2012 issue of Lifelines contains articles on Southern's ancient DNA project, the Pre-dental club, and a pictorial directory of the 2012 biology and allied health graduates.


Why Wasp Foundresses Change Nests: Relatedness, Dominance, And Nest Quality, Perttu Seppä, David C. Queller, Joan E. Strassmann Jan 2012

Why Wasp Foundresses Change Nests: Relatedness, Dominance, And Nest Quality, Perttu Seppä, David C. Queller, Joan E. Strassmann

Biology Faculty Research

The costs and benefits of different social options are best understood when individuals can be followed as they make different choices, something that can be difficult in social insects. In this detailed study, we follow overwintered females of the social wasp Polistes carolina through different nesting strategies in a stratified habitat where nest site quality varies with proximity to a foraging area, and genetic relatedness among females is known. Females may initiate nests, join nests temporarily or permanently, or abandon nests. Females can become helpers or egglayers, effectively workers or queens. What they actually do can be predicted by a …


Plastids And Pathogens: Mechanosensitive Channels And Survival In A Hypoosmotic World, Kira M. Veley, Elizabeth S. Haswell Jan 2012

Plastids And Pathogens: Mechanosensitive Channels And Survival In A Hypoosmotic World, Kira M. Veley, Elizabeth S. Haswell

Biology Faculty Research

In bacteria, MscS-type mechanosensitive channels serve to protect cells from lysis as they swell during extreme osmotic stress. We recently showed that two MscS homologs from Arabidopsis thaliana serve a similar purpose in the epidermal plastids of the leaf, indicating that the plant cell cytoplasm can present a dynamic osmotic challenge to the plastid. MscS homologs are predicted to be targeted to both plastids and mitochondrial envelopes and have been found in the genomes of intracellular pathogens. Here we discuss the implications of these observations, and propose that MS channels provide an essential mechanism for osmotic adaptation to both intracellular …


Amino Acid Repeats Cause Extraordinary Coding Sequence Variation In The Social Amoeba Dictyostelium Discoideum, Clea Scala, Xiangjun Tian, Natasha J. Mehdiabadi, Margaret H. Smith, Gerda Saxer, Katie Stephens, Prince Buzombo, Joan E. Strassmann, David C. Queller Jan 2012

Amino Acid Repeats Cause Extraordinary Coding Sequence Variation In The Social Amoeba Dictyostelium Discoideum, Clea Scala, Xiangjun Tian, Natasha J. Mehdiabadi, Margaret H. Smith, Gerda Saxer, Katie Stephens, Prince Buzombo, Joan E. Strassmann, David C. Queller

Biology Faculty Research

Protein sequences are normally the most conserved elements of genomes owing to purifying selection to maintain their functions. We document an extraordinary amount of within-species protein sequence variation in the model eukaryote Dictyostelium discoideum stemming from triplet DNA repeats coding for long strings of single amino acids. D. discoideum has a very large number of such strings, many of which are polyglutamine repeats, the same sequence that causes various human neurological disorders in humans, like Huntington’s disease. We show here that D. discoideum coding repeat loci are highly variable among individuals, making D. discoideum a candidate for the most variable …


Mscs-Like10 Is A Stretch-Activated Ion Channel From Arabidopsis Thaliana With A Preference For Anions, Grigory Maksaev, Elizabeth S. Haswell Jan 2012

Mscs-Like10 Is A Stretch-Activated Ion Channel From Arabidopsis Thaliana With A Preference For Anions, Grigory Maksaev, Elizabeth S. Haswell

Biology Faculty Research

Like many other organisms, plants are capable of sensing and responding to mechanical stimuli such as touch, osmotic pressure, and gravity. One mechanism for the perception of force is the activation of mechanosensitive (or stretch-activated) ion channels, and a number of mechanosensitive channel activities have been described in plant membranes. Based on their homology to the bacterial mechanosensitive channel MscS, the 10 MscS-Like (MSL) proteins of Arabidopsis thaliana have been hypothesized to form mechanosensitive channels in plant cell and organelle membranes. However, definitive proof that MSLs form mechanosensitive channels has been lacking. Here we used single-channel patch clamp electrophysiology to …


Mechanosensitive Channels Protect Plastids From Hypoosmotic Stress During Normal Plant Growth, Kira M. Veley, Sarah Marshburn, Cara E. Clure, Elizabeth S. Haswell Jan 2012

Mechanosensitive Channels Protect Plastids From Hypoosmotic Stress During Normal Plant Growth, Kira M. Veley, Sarah Marshburn, Cara E. Clure, Elizabeth S. Haswell

Biology Faculty Research

Cellular response to osmotic stress is critical for survival and involves volume control through the regulated transport of osmolytes [1-3]. Organelles may respond similarly to abrupt changes in cytoplasmic osmolarity [4-6]. The plastids of the Arabidopsis thaliana leaf epidermis provide a model system for the study of organellar response to osmotic stress within the context of the cell. An Arabidopsis mutant lacking two plastid-localized homologs of the bacteria mechanosensitive channel MscS (MscS-like [MSL] 2 and 3) exhibits large round epidermal plastids that lack dynamic extensions known as stromules [7]. This phenotype is present under normal growth conditions and does not …


A Role For Mechanosensitive Channels In Chloroplast And Bacterial Fission., Margaret E. Wilson, Elizabeth S. Haswell Jan 2012

A Role For Mechanosensitive Channels In Chloroplast And Bacterial Fission., Margaret E. Wilson, Elizabeth S. Haswell

Biology Faculty Research

The division site in both chloroplasts and bacteria is established by the medial placement of the FtsZ ring, a process that is in part regulated by the evolutionarily conserved components of the Min system. We recently showed that mechanosensitive ion channels influence FtsZ ring assembly in both Arabidopsis thaliana chloroplasts and in Escherichia coli; in chloroplasts they do so through the same genetic pathway as the Min system. Here we describe the effect of heterologous expression of the Arabidopsis MS channel homolog MSL2 on FtsZ ring placement in E. coli. We also discuss possible molecular mechanisms by which MS channels …


A Pre-Embedding Immunogold Approach Reveals Localization Of Myosin Vi At The Ultrastructural Level In The Actin Cones That Mediate Drosophila Spermatid Individualization, Marta Lenartowska, Mamiko Isaji, Kathryn G. Miller Jan 2012

A Pre-Embedding Immunogold Approach Reveals Localization Of Myosin Vi At The Ultrastructural Level In The Actin Cones That Mediate Drosophila Spermatid Individualization, Marta Lenartowska, Mamiko Isaji, Kathryn G. Miller

Biology Faculty Research

Stable actin structures play important roles in the development and specialization of differentiated cells. How these structures form, are organized, and are used to mediate physiological processes is not well understood in most cases. In Drosophila testis, stable actin structures, called actin cones, mediate spermatid individualization, a large-scale cellular remodeling process. These actin cones are composed of two structural domains, a front meshwork and a rear region of parallel bundles. Myosin VI is an important player in proper actin cone organization and function. Myosin VI localizes to the cones' fronts and its specific localization is required for proper actin cone …


Whole Genome Sequencing Of Mutation Accumulation Lines Reveals A Low Mutation Rate In The Social Amoeba Dictyostelium Discoideum, Gerda Saxer, Paul Havlak, Sara A. Fox, Michael A. Quance, Sharu Gupta, Yuriy Fofanov, Joan E. Strassmann, David C. Queller Jan 2012

Whole Genome Sequencing Of Mutation Accumulation Lines Reveals A Low Mutation Rate In The Social Amoeba Dictyostelium Discoideum, Gerda Saxer, Paul Havlak, Sara A. Fox, Michael A. Quance, Sharu Gupta, Yuriy Fofanov, Joan E. Strassmann, David C. Queller

Biology Faculty Research

Spontaneous mutations play a central role in evolution. Despite their importance, mutation rates are some of the most elusive parameters to measure in evolutionary biology. The combination of mutation accumulation (MA) experiments and whole-genome sequencing now makes it possible to estimate mutation rates by directly observing new mutations at the molecular level across the whole genome. We performed an MA experiment with the social amoeba Dictyostelium discoideum and sequenced the genomes of three randomly chosen lines using high-throughput sequencing to estimate the spontaneous mutation rate in this model organism. The mitochondrial mutation rate of 6.76×10(-9), with a Poisson confidence interval …


Structured Growth And Genetic Drift Raise Relatedness In The Social Amoeba Dictyostelium Discoideum, Neil J. Buttery, Chandra N. Jack, Boahemaa Adu-Oppong, Kate T. Snyder, Christoper R L Thompson, David C. Queller, Joan E. Strassmann Jan 2012

Structured Growth And Genetic Drift Raise Relatedness In The Social Amoeba Dictyostelium Discoideum, Neil J. Buttery, Chandra N. Jack, Boahemaa Adu-Oppong, Kate T. Snyder, Christoper R L Thompson, David C. Queller, Joan E. Strassmann

Biology Faculty Research

One condition for the evolution of altruism is genetic relatedness between altruist and beneficiary, often achieved through active kin recognition. Here, we investigate the power of a passive process resulting from genetic drift during population growth in the social amoeba Dictyostelium discoideum. We put labelled and unlabelled cells of the same clone in the centre of a plate, and allowed them to proliferate outward. Zones formed by genetic drift owing to the small population of actively growing cells at the colony edge. We also found that single cells could form zones of high relatedness. Relatedness increased at a significantly …


Mind The Gap: A Comparative Study Of Migratory Behavior In Social Amoebae, Owen M. Gilbert, Jennie J. Kuzdzal-Fick, David C. Queller, Joan E. Strassmann Jan 2012

Mind The Gap: A Comparative Study Of Migratory Behavior In Social Amoebae, Owen M. Gilbert, Jennie J. Kuzdzal-Fick, David C. Queller, Joan E. Strassmann

Biology Faculty Research

Social amoebae aggregate to form a multicellular slug that migrates some distance. Most species produce a stalk during migration, but some do not. We show that Dictyostelium giganteum, a species that produces stalk during migration, is able to traverse small gaps and utilize bacterial resources following gap traversal by shedding live cells. In contrast, we found that Dictyostelium discoideum, a species that does not produce stalk during migration, can traverse gaps only when in the presence of other species’ stalks or other thin filaments. These findings suggest that production of stalk during migration allows traversal of gaps that commonly occurs …


Full Issue: Volume 5, Issue 2 Jan 2012

Full Issue: Volume 5, Issue 2

The Science Journal of the Lander College of Arts and Sciences

No abstract provided.


Full Issue: Volume 6, Number 1 Jan 2012

Full Issue: Volume 6, Number 1

The Science Journal of the Lander College of Arts and Sciences

No abstract provided.


Brown Treesnakes: A Potential Invasive Species For The United States, Samantha Sue Kahl, Scott E. Henke, Marc A. Hall, David K. Britton Jan 2012

Brown Treesnakes: A Potential Invasive Species For The United States, Samantha Sue Kahl, Scott E. Henke, Marc A. Hall, David K. Britton

Human–Wildlife Interactions

Brown treesnakes (ˆ) are mildly venomous, exotic snakes that have the potential to become an invasive species in North America, Hawaii, and the Commonwealth of the Northern Mariana Islands. The snake is native to northern and eastern Australia, New Guinea, and other islands of northern and western Melanesia. The snakes were first found outside their native range on Guam in 1953. The exact date they reached the island is uncertain, but they are believed to have arrived on military cargo transport vessels some time during or just after World War II. During the years that followed, the population of brown …


Quantifying The Impacts Of Oyster Reef Restoration On Oyster Coverage, Wave Attenuation And Seagrass Fragment Retention In Mosquito Lagoon, Florida, Stephanie Garvis Jan 2012

Quantifying The Impacts Of Oyster Reef Restoration On Oyster Coverage, Wave Attenuation And Seagrass Fragment Retention In Mosquito Lagoon, Florida, Stephanie Garvis

Electronic Theses and Dissertations

The goal of this project was to determine the effects of oyster reef restoration on oyster coverage, wave height dissipation and seagrass recruitment. First, to assess the current versus historical coverage of natural, dead and restored oyster reefs within Mosquito Lagoon, aerial photographs from 2009, provided by Saint Johns River Water Management District, were digitized using ArcGIS software. Live reefs, restored reefs and dead reefs were screen digitized using a reef ‘signature’ in order to estimate the area of each type of reef. The 2009 maps were used as a guide to digitizing the historical aerial photographs (1943, 1951, 1967, …


Diversity And Dynamics Of Bacterial Communities In Early Life Stages Of The Caribbean Coral Porites Astreoides, Koty H. Sharp, Dan Distel, Valerie J. Paul Jan 2012

Diversity And Dynamics Of Bacterial Communities In Early Life Stages Of The Caribbean Coral Porites Astreoides, Koty H. Sharp, Dan Distel, Valerie J. Paul

Arts & Sciences Faculty Publications

In this study, we examine microbial communities of early developmental stages of the coral Porites astreoides by sequence analysis of cloned 16S rRNA genes, terminal restriction fragment length polymorphism (TRFLP), and fluorescence in situ hybridization (FISH) imaging. Bacteria are associated with the ectoderm layer in newly released planula larvae, in 4-day-old planulae, and on the newly forming mesenteries surrounding developing septa in juvenile polyps after settlement. Roseobacter clade-associated (RCA) bacteria and Marinobacter sp. are consistently detected in specimens of P. astreoides spanning three early developmental stages, two locations in the Caribbean and 3 years of collection. Multi-response permutation procedures analysis …


Functional Analysis Of Conserved Motifs In The Mechanosensitive Channel Homolog Mscs-Like2 From Arabidopsis Thaliana, Gregory S. Jensen, Elizabeth S. Haswell Jan 2012

Functional Analysis Of Conserved Motifs In The Mechanosensitive Channel Homolog Mscs-Like2 From Arabidopsis Thaliana, Gregory S. Jensen, Elizabeth S. Haswell

Biology Faculty Research

The Mechanosensitive channel of Small conductance (MscS) of Escherichia coli has become an excellent model system for the structural, biophysical, and functional study of mechanosensitive ion channels. MscS, a complex channel with multiple states, contributes to protection against lysis upon osmotic downshock. MscS homologs are widely and abundantly dispersed among the bacterial and plant lineages, but are not found in animals. Investigation into the eukaryotic branch of the MscS family is in the beginning stages, and it remains unclear how much MscS homologs from eukaryotes resemble E. coli MscS with respect to structure, function, and regulation. Here we test the …


Morpholino Gene Knockdown In Adult Fundulus Heteroclitus: Role Of Sgk1 In Seawater Acclimation, Emily G. Notch, Joseph R. Shaw, Bonita A. Coutermarsh, Marisa Dzioba, Bruce A. Stanton Dec 2011

Morpholino Gene Knockdown In Adult Fundulus Heteroclitus: Role Of Sgk1 In Seawater Acclimation, Emily G. Notch, Joseph R. Shaw, Bonita A. Coutermarsh, Marisa Dzioba, Bruce A. Stanton

Dartmouth Scholarship

The Atlantic killifish (Fundulus heteroclitus) is an environmental sentinel organism used extensively for studies on environmental toxicants and salt (NaCl) homeostasis. Previous research in our laboratory has shown that rapid acclimation of killifish to seawater is mediated by trafficking of CFTR chloride channels from intracellular vesicles to the plasma membrane in the opercular membrane within the first hour in seawater, which enhances chloride secretion into seawater, thereby contributing to salt homeostasis. Acute transition to seawater is also marked by an increase in both mRNA and protein levels of serum glucocorticoid kinase 1 (SGK1) within 15 minutes of transfer. …


Population Status, Habitat Dependence, And Reproductive Ecology Of Bahama Orioles: A Critically Endangered Synanthropic Species, Melissa R. Price, Valerie A. Lee, William K. Hayes Dec 2011

Population Status, Habitat Dependence, And Reproductive Ecology Of Bahama Orioles: A Critically Endangered Synanthropic Species, Melissa R. Price, Valerie A. Lee, William K. Hayes

Faculty Works

Recent elevation of critically endangered Bahama Orioles (Icterus northropi) to species status prompted us to evaluate their population status, habitat use, and breeding ecology. From surveys, we estimated that at least 141 to 254 individuals remain globally, with 90 to 162, 24 to 44, and 27 to 48 individuals remaining on North Andros Island, Mangrove Cay, and South Andros Island, The Bahamas, respectively. Orioles were observed nesting exclusively in anthropogenic habitat (residential and agricultural land), but home ranges also included nearby pine forest and coppice (dry broadleaf forest). Most nests (40 of 46, or 87%) were in nonnative coconut palm …


Hands-On Labs (Hol): Using Technology And Web-Based Resources To Transform A Traditional Lab-Based Biology Course Into A Distance Learning (Dl) Hybrid Course, Across Schools At Pace University., Erica Kipp Dec 2011

Hands-On Labs (Hol): Using Technology And Web-Based Resources To Transform A Traditional Lab-Based Biology Course Into A Distance Learning (Dl) Hybrid Course, Across Schools At Pace University., Erica Kipp

Cornerstone 3 Reports : Interdisciplinary Informatics

No abstract provided.


Lifelines Fall 2011, Southern Adventist University Oct 2011

Lifelines Fall 2011, Southern Adventist University

Lifelines - Biology Department Newsletter

The Fall 2011 issue of Lifelines features articles on biology student research, the pre-professional campout, and new professors Dr. Timothy Trott and Dr. Lucinda Hill.


Lytopylus Förster (Hymenoptera, Braconidae, Agathidinae) Species From Costa Rica, With An Emphasis On Specimens Reared From Caterpillars In Area De Conservación Guanacaste, Michael J. Sharkey, Stephanie Clutts, Erika M. Tucker, Daniel Janzen, Winnie Hallwachs, Tanya Dapkey, M. Alex Smith Sep 2011

Lytopylus Förster (Hymenoptera, Braconidae, Agathidinae) Species From Costa Rica, With An Emphasis On Specimens Reared From Caterpillars In Area De Conservación Guanacaste, Michael J. Sharkey, Stephanie Clutts, Erika M. Tucker, Daniel Janzen, Winnie Hallwachs, Tanya Dapkey, M. Alex Smith

Entomology Faculty Publications

Twelve species of Costa Rican Lytopylus are treated; these include all species reared from Lepidoptera caterpillars in Area de Conservación Guanacaste, Costa Rica, over 32 years of caterpillar inventory, as well as two species recorded in the literature as occurring in Costa Rica. Ten new species are described, i.e., Lytopylus bradzlotnicki, Lytopylus colleenhitchcockae, Lytopylus gregburtoni, Lytopylus jessicadimauroae, Lytopylus jessiehillae, Lytopylus mingfangi, Lytopylus rebeccashapleyae, Lytopylus robpringlei, Lytopylus sandraberriosae, Lytopylus vaughntani. The following species are transferred to Lytopylus: Metriosoma flavicalcar Enderlein 1920 to Lytopylus flavicalcarcomb. n.; Bassus macadamiae Briceño and Sharkey 2000 to Lytopylus macadamiaecomb. n.; Metriosoma bicarinatum Enderlein 1920 to Lytopylus …