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2014

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Articles 1051 - 1080 of 1587

Full-Text Articles in Biology

Spatiotemporal Variability And Sound Characterization In Silver Croaker Plagioscion Squamosissimus (Sciaenidae) In The Central Amazon, Alfredo Borie, Hin-Kiu Mok, Ning L. Chao, Michael L. Fine Jan 2014

Spatiotemporal Variability And Sound Characterization In Silver Croaker Plagioscion Squamosissimus (Sciaenidae) In The Central Amazon, Alfredo Borie, Hin-Kiu Mok, Ning L. Chao, Michael L. Fine

Biology Publications

Background

The fish family Sciaenidae has numerous species that produce sounds with superfast muscles that vibrate the swimbladder. These muscles form post embryonically and undergo seasonal hypertrophy-atrophy cycles. The family has been the focus of numerous passive acoustic studies to localize spatial and temporal occurrence of spawning aggregations. Fishes produce disturbance calls when hand-held, and males form aggregations in late afternoon and produce advertisement calls to attract females for mating. Previous studies on five continents have been confined to temperate species. Here we examine the calls of the silver croakerPlagioscion squamosissimus, a freshwater equatorial species, which experiences constant …


Toxicodynamic Modeling Of 137cs To Estimate White-Tailed Deer Background Levels For The Department Of Energy's Savannah River Site, Karen F. Gaines, James M. Novak, Christopher W. Bobryk, Susan A. Blas Jan 2014

Toxicodynamic Modeling Of 137cs To Estimate White-Tailed Deer Background Levels For The Department Of Energy's Savannah River Site, Karen F. Gaines, James M. Novak, Christopher W. Bobryk, Susan A. Blas

Faculty Research & Creative Activity

The U.S. Department of Energy's (USDOE) Savannah River Site (SRS) is a former nuclear weapon material production and current research facility adjacent to the Savannah River in South Carolina, USA. The purpose of this study was to determine the background radiocesium (137Cs) body burden (e.g., from global fallout) for white-tailed deer (Odocoileus virginianus) inhabiting the SRS. To differentiate what the background burden is for the SRS versus 137Cs obtained from SRS nuclear activities, data were analyzed spatially, temporally and compared to other off-site hunting areas near the SRS. The specific objectives of this study were: to compare SRS and offsite …


Trophic Dynamics Of U, Ni, Hg And Other Contaminants Of Potential Concern On The Department Of Energy’S Savannah River Site, Paul G. Edwards, Karen F. Gaines, A. Lawrence Bryan Jr., James M. Novak, Susan A. Blas Jan 2014

Trophic Dynamics Of U, Ni, Hg And Other Contaminants Of Potential Concern On The Department Of Energy’S Savannah River Site, Paul G. Edwards, Karen F. Gaines, A. Lawrence Bryan Jr., James M. Novak, Susan A. Blas

Faculty Research & Creative Activity

The Department of Energy’s Savannah River Site is a former nuclear weapon material production and current research facility located in South Carolina, USA. Wastewater discharges from a fuel and nuclear reactor target manufacturing facility released depleted and natural U, as well as other metals into the Tims Branch- Steed Pond water system. We investigated the current dynamics of this system for the purposes of environmental monitoring and assessment by examining metal concentrations, bioavailability, and trophic transfer of contaminants in seven ponds. Biofilm, detritus, and Anuran and Anisopteran larvae were collected and analyzed for stable isotopes (δ15N, δ13C) and contaminants of …


Fishes Of Eastern Washington: A Natural History, Volume 1, Allan T. Scholz, Tyler Basler, Josh Smith, Judy Mcmillan, Larry Conboy, Eastern Washington University. Department Of Biology., Eastern Washington University. University Graphics. Jan 2014

Fishes Of Eastern Washington: A Natural History, Volume 1, Allan T. Scholz, Tyler Basler, Josh Smith, Judy Mcmillan, Larry Conboy, Eastern Washington University. Department Of Biology., Eastern Washington University. University Graphics.

Biology Faculty Publications

Volume 1 of 4.

CHAPTER 1: INTRODUCTION, CHAPTER 2: CHECKLISTS OF EXTANT AND FOSSIL FISHES FOUND IN EASTERN WASHINGTON, CHAPTER 3: THE DISCOVERERS, CHAPTER 4: GEOLOGY, CHAPTER 5: COLUMBIA RIVER BASIN HYDROLOGY AND FISH DISTRIBUTION IN EASTERN WASHINGTON


Fishes Of Eastern Washington: A Natural History, Volume 2, Allan T. Scholz, Tyler Basler, Josh Smith, Judy Mcmillan, Larry Conboy, Eastern Washington University. Department Of Biology., Eastern Washington University. University Graphics. Jan 2014

Fishes Of Eastern Washington: A Natural History, Volume 2, Allan T. Scholz, Tyler Basler, Josh Smith, Judy Mcmillan, Larry Conboy, Eastern Washington University. Department Of Biology., Eastern Washington University. University Graphics.

Biology Faculty Publications

Volume 2 of 4.

CHAPTER 6: KEY TO FAMILIES OF EASTERN WASHINGTON FISHES, CHAPTER 7: FAMILY PETROMYZONTIDAE: LAMPREYS, CHAPTER 8: FAMILY ACIPENSERIDAE: STURGEON, CHAPTER 9: FAMILY CLUPEIDAE: HERRINGS, CHAPTER 10: FAMILY CYPRINIDAE: CARPS AND MINNOWS, CHAPTER 11: Family Catostomidae: Suckers, CHAPTER 12: FAMILY ICTALURIDAE: BULLHEAD CATFISHES, CHAPTER 13: Family Esocidae: Pikes


Fishes Of Eastern Washington: A Natural History, Volume 3, Allan T. Scholz, Josh Smith, Amanda Maifeld, Judy Mcmillan, Larry Conboy, Eastern Washington University. Department Of Biology., Eastern Washington University. University Graphics. Jan 2014

Fishes Of Eastern Washington: A Natural History, Volume 3, Allan T. Scholz, Josh Smith, Amanda Maifeld, Judy Mcmillan, Larry Conboy, Eastern Washington University. Department Of Biology., Eastern Washington University. University Graphics.

Biology Faculty Publications

Volume 3 of 4.

CHAPTER 14: FAMILY SALMONIDAE: SALMON, TROUT, CHARR, WHITEFISH AND GRAYLINGS, CHAPTER 15: FAMILY SALMONIDAE (SUBFAMILY COREGONINAE): WHITEFISH, CHAPTER 16: FAMILY SALMONIDAE (SUBFAMILY MONINAE): SALMON, TROUT AND CHARR, CHAPTER 17: FAMILY SALMONIDAE (SUBFAMILY THYMALLINAE): GRAYLINGS


Effects Of Polychlorinated Biphenyl (Pcb) Exposure On Response Perseveration And Ultrasonic Vocalization Emission In Rat During Development, Dena Krishnan, Howard C. Cromwell, Lee Meserve Jan 2014

Effects Of Polychlorinated Biphenyl (Pcb) Exposure On Response Perseveration And Ultrasonic Vocalization Emission In Rat During Development, Dena Krishnan, Howard C. Cromwell, Lee Meserve

Biological Sciences Faculty Publications

The 3 major symptoms of autistic spectrum disorders include 1) social behavioral alterations, 2) problems in communication and 3) higher-order motoric deficits of perseveration and stereotyped movements. Previous work has shown that early developmental exposure to polychlorinated biphenyls (PCBs) alters rat pup social motivation and juvenile rat social recognition/investigation. The present work extends this previous research by examining how perinatal PCB exposure alters motoric functions and communication abilities at different stages of development. Action perseveration was examined using performance measures from a T-maze environment. Communication abilities were evaluated by monitoring ultrasound emission in rat pups during a brief isolation from …


Central Coast Groundfish Species And Fillet Identification Manual, Robbie Milla Jan 2014

Central Coast Groundfish Species And Fillet Identification Manual, Robbie Milla

Agricultural Education and Communication

The purpose of this project was to create a manual that would aid fishermen and fish consumers in the successful identification of various groundfish species and their fillets. The manual was crafted with quality photographs to give the viewer a vivid depiction of the targeted groundfish species. The images were taken to specifically target the identification characteristics of each fish species. It was the hope of the author to educate anyone who was interested in the groundfish fishery. The manual includes: basic groundfish regulations, groundfish species identification, and groundfish fillet identification.


Little Evidence For Local Adaptation To Soils Or Microclimate In The Post-Fire Recruitment Of Three Californian Shrubs, Annette Bieger, Nishanta Rajakaruna, Susan Harrison Jan 2014

Little Evidence For Local Adaptation To Soils Or Microclimate In The Post-Fire Recruitment Of Three Californian Shrubs, Annette Bieger, Nishanta Rajakaruna, Susan Harrison

Biological Sciences

Background: Seedling recruitment following fire is an infrequent yet critical demographic transition for woody plants in Mediterranean ecosystems.

Aims: Here we examine whether post-fire seedling recruitment of three widespread Californian chaparral shrubs is affected by local adaptation within an edaphically and topographically complex landscape.

Methods: We reciprocally transplanted 6-month-old seedlings of Adenostema fasciculatum, Ceanothus cuneatus and Eriodictyon californicum to serpentine and sandstone soils, and cool northerly and warm southerly slopes.

Results: At the age of 2 years, none of the species manifested higher survival or growth on ‘home’ compared with ‘away’ soils or slopes, indicating an absence of local …


The Role Of Elevation And Soil Chemistry In The Distribution And Ion Accumulation Of Floral Morphs Of Streptanthus Polygaloides Gray (Brassicaceae), A Californian Nickel Hyperaccumulator, Nathaniel S. Pope, Michael Fong, Robert S. Boyd, Nishanta Rajakaruna Jan 2014

The Role Of Elevation And Soil Chemistry In The Distribution And Ion Accumulation Of Floral Morphs Of Streptanthus Polygaloides Gray (Brassicaceae), A Californian Nickel Hyperaccumulator, Nathaniel S. Pope, Michael Fong, Robert S. Boyd, Nishanta Rajakaruna

Biological Sciences

Background: The flora of serpentine/ultramafic soils provides an excellent model system for the study of natural selection in plant populations. Streptanthus polygaloides is a nickel hyperaccumulator that is endemic to serpentine soils in the Sierra Nevada of California, and has four floral morphs (yellow, purple, yellow-to-purple and undulate).

Aims: We investigate three hypotheses: (1) the purple morph occurs in colder, wetter climates than the yellow morph; (2) tissue–soil ionic relationships differ among morphs; and (3) morphs occur on soils with differing elemental concentrations.

Methods: We queried herbarium records to investigate patterns of occurrence among the yellow and purple floral morphs, …


The Unseen World: Environmental Microbial Sequencing And Identification Methods For Ecologists, Naupaka B. Zimmerman, J. Izard, C. Klatt, J. Zhou, E. Aronson Jan 2014

The Unseen World: Environmental Microbial Sequencing And Identification Methods For Ecologists, Naupaka B. Zimmerman, J. Izard, C. Klatt, J. Zhou, E. Aronson

Biology Faculty Publications

Microorganisms inhabit almost every environment, comprise the majority of diversity on Earth, are important in biogeochemical cycling, and may be vital to ecosystem responses to large-scale climatic change. In recent years, ecologists have begun to use rapidly advancing molecular techniques to address questions about microbial diversity, biogeography, and responses to environmental change. Studies of microbes in the environment generally focus on three broad objectives: determining which organisms are present, what their functional capabilities are, and which are active at any given time. However, comprehending the range of methodologies currently in use can be daunting. To provide an overview of environmental …


Filarial Nematode Infection In Ixodes Scapularis Ticks Collected From Southern Connecticut, Pabbati Namrata, Jamie M. Miller, Madari Shilpa, Patlolla Raghavender Reddy, Cheryl Bandoski,, Michael J. Rossi, Eva Sapi Jan 2014

Filarial Nematode Infection In Ixodes Scapularis Ticks Collected From Southern Connecticut, Pabbati Namrata, Jamie M. Miller, Madari Shilpa, Patlolla Raghavender Reddy, Cheryl Bandoski,, Michael J. Rossi, Eva Sapi

Biology and Environmental Science Faculty Publications

It was recently demonstrated that the lone star tick Amblyomma americanum could harbor filarial nematodes within the genus Acanthocheilonema. In this study, Ixodes scapularis (deer) ticks collected from Southern Connecticut were evaluated for their potential to harbor filarial nematodes. Non-engorged nymphal and adult stage Ixodes scapularis ticks were collected in Southern Connecticut using the standard drag method. In situ hybridization with filarial nematode specific sequences demonstrated the presence of filarial nematodes in Ixodes ticks. Filarial nematode specific DNA sequences were amplified and confirmed by direct sequencing in Ixodes nymphal and adult ticks using either general filarial nematode or Onchocercidae family …


Complete Genome Sequence Of Anabaena Variabilis Atcc 29413, Teresa Thiel, Brenda Pratte, Jinshun Zhong, Lynne Goodwin, Alex Copeland, Susan Lucas, Cliff Han, Sam Pitluck, Miriam Land, Nikos Kyrpides, Tanja Woyke Jan 2014

Complete Genome Sequence Of Anabaena Variabilis Atcc 29413, Teresa Thiel, Brenda Pratte, Jinshun Zhong, Lynne Goodwin, Alex Copeland, Susan Lucas, Cliff Han, Sam Pitluck, Miriam Land, Nikos Kyrpides, Tanja Woyke

Biology Department Faculty Works

Anabaena variabilis ATCC 29413 is a filamentous, heterocyst-forming cyanobacterium that has served as a model organism, with an extensive literature extending over 40 years. The strain has three distinct nitrogenases that function under different environmental conditions and is capable of photoautotrophic growth in the light and true heterotrophic growth in the dark using fructose as both carbon and energy source. While this strain was first isolated in 1964 in Mississippi and named Anabaena flos-aquae MSU A-37, it clusters phylogenetically with cyanobacteria of the genus Nostoc. The strain is a moderate thermophile, growing well at approximately 40° C. Here we provide …


A Selected Surveyo F Ocean Acidifcation's Effect On Coccolithophore And Other Marine Ecosystems, Taylor Zaw, Joel Wood, Anthony Gonzalez Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 …


Vegfr-2 And Vegfr-3 Expression As A Function Of Jagged-1 Over-Expression In Huvec Cells, Caleb Stubbs Jan 2014

Vegfr-2 And Vegfr-3 Expression As A Function Of Jagged-1 Over-Expression In Huvec Cells, Caleb Stubbs

Featured Research

Angiogenesis is the sprouting of new blood vessels from pre-existing vessels initiated from vascular endothelial cells in response to exogenous chemical signals. Principle signals are vascular endothelial growth factors (VEGF) that direct cell growth and differentiation by binding to endothelial cell surface VEGF receptors (VEGFR). In Human Umbilical Vascular Endothelial Cells (HUVEC) initial sprouting cells or “tip cells” send signals to neighboring cells “stalk cells” responsible for sprout elongation. Multiple VEGF signals and receptors are known, but the main angiogenic signals are from VEGF-A through VEGFR-2 and VEGFR-3. Regulation of VEGF receptor expression can be influenced by the Notch signaling …


Effect Of Shear Stress Direction On Endothelial Function And Enos Phosphorylation In Soleus Feed Arteries, Blanca B. Perez, Jay Brewster, Jeffrey Jasperse Jan 2014

Effect Of Shear Stress Direction On Endothelial Function And Enos Phosphorylation In Soleus Feed Arteries, Blanca B. Perez, Jay Brewster, Jeffrey Jasperse

Featured Research

Blood flow feeding tissues and organs is closely regulated in order to meet metabolic and functional needs. Control of blood flow is accomplished by regulating the diameter of the arteries and arterioles feeding different organs. Several neural, hormonal, chemical and mechanical mechanisms contribute to the constriction and dilation of arteries. Shear stress, the frictional force created by streaming blood on the endothelial layer of arteries, is one of these mechanical mechanisms (1). Shear stress causes both acute and long term effects on endothelial cells (1,2,5).

Blood in arteries typically flows away from the heart towards organs (causing antegrade shear stress) …


Differential Survival Of Chaparral Shrub Species In Response To Severe Drought, Hannah Dario Jan 2014

Differential Survival Of Chaparral Shrub Species In Response To Severe Drought, Hannah Dario

Featured Research

In this experiment, we examined how the plants in the Santa Monica Mountains are responding to the driest period in recorded history for California. Our hypothesis was that plant species with the deepest roots would have highest survivorship. We thought this because deep-rooted shrubs will have greater access to soil moisture. This hypothesis was tested by collecting data on plant survival, in a mixed chaparral stand, containing eleven species, growing in the Green Valley Preserve off of Stunt road, in the Santa Monica Mountains. The chaparral stand was 21 years old, having last burned in 1993 (Old Topanga Canyon Fire). …


Effects Of Uv-Radiation On Feeding Behavior In Dendrobates Tinctorius, Taylor S. Stucky, Arthur Garnica Jan 2014

Effects Of Uv-Radiation On Feeding Behavior In Dendrobates Tinctorius, Taylor S. Stucky, Arthur Garnica

Featured Research

UV-B levels have recently been increasing with the depletion of the ozone layer. Recent data have shown that amphibians are especially susceptible to UV-B, with poison dart frogs being one focus in these studies. The purpose of this study was to determine if UV-B radiation affects the foraging behavior of poison dart frogs. This study was conducted with a captive population of juvenile Dendrobates tinctorius at Pepperdine University in Malibu, California. Frogs underwent one of three treatments: UV only, Food only, and UV and Food. UV only trials were conducted using two UV lights emitting approximately 1.2 uW/cm2 of UV …


Enzymatic Activity In The Chorion For Hatching In The California Grunion, Emily R. Pierce, Vince V. Quach, Karen L. Martin Jan 2014

Enzymatic Activity In The Chorion For Hatching In The California Grunion, Emily R. Pierce, Vince V. Quach, Karen L. Martin

Featured Research

Leuresthes tenuis is a small, silverside fish that spawns on the beaches during some of the highest tides of the summer months. Of the many unique traits to the species including that the eggs develop fully out of water to the point of hatching competence but will not hatch until presented with an environmental cue, which causes them to hatch in less than a minute. The purpose of this study is to better understand the role of enzymes called chorionases, which act to break down the chorion (egg membrane). I hypothesize that the chorion begins to weaken in this species …


The Effects Of Carbon Black On Cell Viability, Abigail Calixto, Jay Brewster Jan 2014

The Effects Of Carbon Black On Cell Viability, Abigail Calixto, Jay Brewster

Featured Research

Carbon black (CB) is a type of nanoparticle that is found in air pollution and is a known environmental toxin. The purpose of this work is to evaluate whether CB exposure activates cell death via apoptosis in cultured cell lines, supporting future work focused upon assessing the signaling pathways that might be induced by this exposure. Using adenocarcinomic human alveolar basal epithelial (A549) and baby hamster kidney (BHK-21) cells, we hypothesized that carbon black exposure causes cell death and potentially stress signaling via the endoplasmic reticulum (ER). The cells were exposed to CB and data collected for varied doses and …