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Articles 1291 - 1320 of 1541

Full-Text Articles in Life Sciences

Biology And Ecology Of Wild Radish (Raphanus Raphanistrum), Mayank Malik May 2009

Biology And Ecology Of Wild Radish (Raphanus Raphanistrum), Mayank Malik

All Dissertations

Wild radish ( L.), a facultative winter annual is a troublesome weed in small grain crops of the Southeastern United States. Besides being a weed, it may also be used as a cover crop for weed management due to its production of glucosinolates. Studies were conducted to evaluate the biology and ecology of wild radish as well as its glucosinolate production and its weed management possibilities.
Wild radish emerging in fall months formed a rosette of leaves which aided its winter survival. Plants emerging from December through March that did not form a rosette had minimal survival. Wild radish life …


An Analysis Of The Environmental And Hormonal Effects On The Growth And Development Of The Moss Ceratodon Purpureus, Megan Knight Apr 2009

An Analysis Of The Environmental And Hormonal Effects On The Growth And Development Of The Moss Ceratodon Purpureus, Megan Knight

Undergraduate Honors Thesis Collection

Ceratodon has not been documented in scientific literature as thoroughly as other species of moss such as Funaria or Tortula. Commonly known as fire moss or purple horned moss, Ceratodon is often reddish or yellow-brown and the spore capsules are usually purple (Crum, 1983). A picture of the species growing in its natural habitat is shown in Figure 4. Ceratodon often grows in tufts and is considered a weed, often thriving in polluted or disturbed areas and frequently invading after a fire (Crum 1983). Ceratodon belongs to the class Bryopsida, which also contains the previously mentioned Funaria and Tortula species. …


Common-Path Multimodal Optical Microscopy, Marla Tipping, Chandra S. Yelleswarapu, Sri-Rajasekhar Kothapalli, Alexey Veraksa, D.V.G.L.N. Rao Apr 2009

Common-Path Multimodal Optical Microscopy, Marla Tipping, Chandra S. Yelleswarapu, Sri-Rajasekhar Kothapalli, Alexey Veraksa, D.V.G.L.N. Rao

Biology Faculty Publications

We have developed a common-path multimodal optical microscopy system that is capable of using a single optical source and a single camera to image amplitude, phase, and fluorescence features of a biological specimen. This is achieved by varying either contrast enhancement filters at the Fourier plane and/or neutral density/fluorescence filters in front of the CCD camera. The feasibility of the technique is demonstrated by obtaining brightfield, fluorescence, phase-contrast, spatially filtered, brightfield + fluorescence, phase +fluorescence, and edge-enhanced+fluorescence images of the same Drosophila embryo without the need for image registration and fusion. This comprehensive microscope has the capability of providing both …


Stem Cell Order Was Immoral And Unnecessary, Nicanor Austriaco Apr 2009

Stem Cell Order Was Immoral And Unnecessary, Nicanor Austriaco

Theology Faculty Publications

No abstract provided.


Faculty Should Consider Peer Review As A Means Of Improving Students' Scientific Reasoning Skill, Briana Eileen Timmerman, Denise Strickland Mar 2009

Faculty Should Consider Peer Review As A Means Of Improving Students' Scientific Reasoning Skill, Briana Eileen Timmerman, Denise Strickland

Faculty Publications

The following article provides highlights of a larger body of work on the impact of peer review on undergraduate biology students’ scientific reasoning, scientific writing and attitudes. Results suggest that undergraduates, even freshman can be effective peer reviewers and that peer review improves scientific writing, content knowledge, and scientific reasoning skills. Students report peer review to be a beneficial experience both within the course and in terms of helping them to develop as aspiring scientists. Science faculty are therefore encouraged to consider incorporating peer review as a regular part of instruction.


Children Should Be Begotten And Not Made, Nicanor Austriaco Mar 2009

Children Should Be Begotten And Not Made, Nicanor Austriaco

Theology Faculty Publications

No abstract provided.


From Cells To Coastlines: How Can We Use Physiology To Forecast The Impacts Of Climate Change?, Brian Helmuth Mar 2009

From Cells To Coastlines: How Can We Use Physiology To Forecast The Impacts Of Climate Change?, Brian Helmuth

Faculty Publications

The interdisciplinary fields of conservation physiology, macrophysiology, and mechanistic ecological forecasting have recently emerged as means of integrating detailed physiological responses to the broader questions of ecological and evolutionary responses to global climate change. Bridging the gap between large-scale records of weather and climate (as measured by remote sensing platforms, buoys and ground-based weather stations) and the physical world as experienced by organisms (niche-level measurements) requires a mechanistic understanding of how ‘environmental signals’ (parameters such as air, surface and water temperature, food availability, water flow) are translated into signals at the scale of the organism or cell (e.g. body temperature, …


An Essay On Evolution: Evolution And The Origin Of Life Are Separate And Distinct Concepts, Kenneth Nickerson Feb 2009

An Essay On Evolution: Evolution And The Origin Of Life Are Separate And Distinct Concepts, Kenneth Nickerson

Kenneth Nickerson Papers

Two years ago on a Saturday morning, I was asked quite pointedly by two friends how I could be both spiritual and a scientist. My questioning friends felt that these qualities were incompatible. It turned out their church taught that scientists were ‘the enemy’ because scientists believe in evolution. Since that time, Letters to the Editor regarding evolution have attracted my attention. Many of the published letters stated that the author did not believe in evolution, and argued in support of his/her position that God had created life. The authors thoroughly confuse two concepts which are separate and distinct: Evolution …


Biology And Conservation Of Horseshoe Crabs, John T. Tanacredi, Mark L. Bottom, David R. Smith Jan 2009

Biology And Conservation Of Horseshoe Crabs, John T. Tanacredi, Mark L. Bottom, David R. Smith

School of Marine and Environmental Sciences Faculty and Staff Publications and Presentations

We dedicate this book to Drs. Carl N. Shuster, Jr. and Koichi Sekiguchi for their life-long contributions to the biology and conservation of the magnificent horseshoe crab.


Lifelines Winter 2009, Southern Adventist University Jan 2009

Lifelines Winter 2009, Southern Adventist University

Lifelines - Biology Department Newsletter

The Winter 2009 issue of Lifelines features articles on RAM Clinics, Dr. Earl Aagaard's retirement, the addition of Richard Seidel to the faculty, and a pictorial directory of the 2009 biology and allied health graduates.


Comparison Of Uva Absorbance In Sun And Shade Leaves, James Newton, Kevin Rivera, James Kim Jan 2009

Comparison Of Uva Absorbance In Sun And Shade Leaves, James Newton, Kevin Rivera, James Kim

Featured Research

In observing chaparral species’ resistance to abiotic plant stresses, this investigation sought to study plant defense against UVA radiation in sun and shade leaves. We predicted that sun leaves would have higher absorbance of UV radiation considering their day-long exposure to sunlight.

UVA (350nm-400nm) absorbance in sun and shade leaves of Heteromeles arbutifolia and Malosma laurina were measured using an integrating sphere. Four leaves from each group were surveyed for reflectance and absorbance. Using the spectrophotometer, reflectance in the green wavelengths (500-600nm) was measured and divided by reflectance in the red (600-700nm) to give a quantitative estimation of the redness …


Measuring Water Use Efficiency In Large And Small Leaves Of Malosma Laurina, Caitlin Ishibashi, Dan Kaczrowski, Evan Mattiansen Jan 2009

Measuring Water Use Efficiency In Large And Small Leaves Of Malosma Laurina, Caitlin Ishibashi, Dan Kaczrowski, Evan Mattiansen

Featured Research

Our study set out to compare Water Use Efficiency (WUE) levels of Malosma laurina plants in both small and large leaves. We collected a total of 3 data sets, with each set consisting of 5 small leaves and 5 large leaves from a single specimen of Malosma laurina located on Pepperdine’s campus. Parameters including transpiration and photosynthesis were measured to calculate WUE of small and large leaves using an LI- 6400 Gas Exchange System. We hypothesized that small leaves would have a higher WUE rate than large leaves of the M. laurina. Analysis of this data via a paired …


The Effects Of Light Intensity And Color Absorption Of Diurnal Leaf Movements Of Malva Parviflora, Amy Lawrence, Ben Young, Matthew Yarborough Jan 2009

The Effects Of Light Intensity And Color Absorption Of Diurnal Leaf Movements Of Malva Parviflora, Amy Lawrence, Ben Young, Matthew Yarborough

Featured Research

Our group measured the heliotropic response rate of the Malva parviflora under various light environments in order to see the effect that light color and intensity had on daily leaf movement. In our experiment we measured the leaf angle of plants under white, blue, red and green light, as well as plants under shade, over a specific duration of time in order to determine the rate of change. We ran a One-Way Analysis of Variance on leaf angle for light color as well as coverage at a 0.05 level using SPSS 17.0. The ANOVA test showed no significance for light …


Soil Salinity And Stomatal Conductance On Chaparral Plants, Ron King, Lisa Malyak, Kelly Rausch Jan 2009

Soil Salinity And Stomatal Conductance On Chaparral Plants, Ron King, Lisa Malyak, Kelly Rausch

Featured Research

In our experiment we evaluated the soil salinity and corresponding stomatal conductance rates of Malosma laurina and Rhus integrifolia located near the coast and farther inland. Our prediction was that stomatal conductance would vary with the change in location of each species. Stomatal conductance was measured using a simple diffusion porometer and soil salinity was measured using a refractometer. We concluded that soil salinity caused a decline in stomatal conductance in both chaparral species. M. laurina was also found to be more sensitive to an increase in soil salinity, as its stomatal conductance rates declined more than that of R. …


Carbon Dioxide Expulsion By Ceanothus Spinosus In Response To Predawn Sunlight, Eian Carter, Jon Pauwels, Brittany Wilkins Jan 2009

Carbon Dioxide Expulsion By Ceanothus Spinosus In Response To Predawn Sunlight, Eian Carter, Jon Pauwels, Brittany Wilkins

Featured Research

In our experiment we studied the respiratory qualities of green bark ceanothus (Ceanothus spinosus). Plants are generally thought to undergo respiration during the night, building up carbon dioxide stores that are released in response to light. In resprouts with large root crowns, such as C. spinosus, we expected to see large amounts of carbon dioxide released right after dawn. This can be shown with the use of a portable gas exchange system. In C. spinosus, we compared normal respiration rates, based on carbon dioxide expulsion, to values obtained at predawn. We were able to show that …


The Effect Of Hydraulic Lift In Quercus Agrifolia On The Health Of Venegasia Carpesioides, Kelly Donovan, Brittany Wagner Jan 2009

The Effect Of Hydraulic Lift In Quercus Agrifolia On The Health Of Venegasia Carpesioides, Kelly Donovan, Brittany Wagner

Featured Research

Hydraulic lift was studied in live and dead Quercus agrifolia (Coastal Live Oak) in order to test its impact on surrounding Venegasia carpesioides (Canyon Sunflower). Hydraulic lift causes soil moisture to rise around the base of deep-rooted plants where neighboring plants can utilize this excess water. We predicted that the hydraulic lift of the Coastal Live Oak would increase soil moisture, causing higher stomatal conductance and higher water potential in nearby plants. Pvalues of .5258 and .6392 indicated there were no significant differences in soil moisture or in stomatal conductance of the Canyon Sunflowers. A p-value of .0378 showed a …


Coiled-Coil-Mediated Dimerization Is Not Required For Myosin Vi To Stabilize Actin During Spermatid Individualization In Drosophila Melanogaster, Tatsuhiko Nogushi, Deborah J. Frank, Mamiko Isaji, Kathryn G. Miller Jan 2009

Coiled-Coil-Mediated Dimerization Is Not Required For Myosin Vi To Stabilize Actin During Spermatid Individualization In Drosophila Melanogaster, Tatsuhiko Nogushi, Deborah J. Frank, Mamiko Isaji, Kathryn G. Miller

Biology Faculty Research

Myosin VI is a pointed-end-directed actin motor that is thought to function as both a transporter of cargoes and an anchor, capable of binding cellular components to actin for long periods. Dimerization via a predicted coiled coil was hypothesized to regulate activity and motor properties. However, the importance of the coiled-coil sequence has not been tested in vivo. We used myosin VI's well-defined role in actin stabilization during Drosophila spermatid individualization to test the importance in vivo of the predicted coiled coil. If myosin VI functions as a dimer, a forced dimer should fully rescue myosin VI loss of function …


Biology In Mathematics At The University Of Richmond, Lester Caudill Jan 2009

Biology In Mathematics At The University Of Richmond, Lester Caudill

Department of Math & Statistics Faculty Publications

In an effort to meet the needs of science students for modeling skills, three new courses have been created at the University of Richmond: Scientific Calculus I and II, and Mathematical Models in Biology and Medicine. The courses are described, and lessons learned and future directions are discussed.


Numerical Modeling Of Hemodynamics In The Thoracic Aorta And Alterations By Dacron Patch Treatment Of Aortic Coarctation, Ronak Jashwant Dholakia Jan 2009

Numerical Modeling Of Hemodynamics In The Thoracic Aorta And Alterations By Dacron Patch Treatment Of Aortic Coarctation, Ronak Jashwant Dholakia

Master's Theses (2009 -)

Coarctation of the aorta (CoA) is a major congenital heart disease, characterized by a severe stenosis of the proximal descending thoracic aorta. Traditionally, surgery has been the treatment of choice for CoA. Dacron patch aortoplasty gained increased popularity after its introduction in the mid-twentieth century due to its advantages over other surgical treatment methods available at the time. A major complication with Dacron patch aortoplasty has been the formation of late aneurysm with as much as 51% incidence reported in follow up studies. The change in aortic morphology and formation of aneurysms after Dacron patch surgery could lead to local …


Gamebird 2006: Quail Vi And Perdix Xii, Sandra B. Cederbaum, Brant C. Faircloth, Theron M. Terhune, Jeffrey J. Thompson, John P. Carroll Jan 2009

Gamebird 2006: Quail Vi And Perdix Xii, Sandra B. Cederbaum, Brant C. Faircloth, Theron M. Terhune, Jeffrey J. Thompson, John P. Carroll

School of Natural Resources: Faculty Publications

Foreword v

Acknowledgements vi

Editorial Panel vii

Sponsors x

Invited Manuscripts 2

Integrating Management, Research, and Monitoring: Balancing the 3-Legged Stool. Michael J. Conroy & James T. Peterson . 2

Management of Southern African Gamebirds: Opportunities and Threats. Tim Crowe . 11

Taking the Northern Bobwhite Conservation Initiative to the Next Level. Donald F. McKenzie . 16

Restoring a Gray Partridge (Perdix perdix) Population and the Future of Predation Control. G.R. Potts . 24

Abundance Estimation 27

The GWCT Partridge Count Scheme: A Volunteer-Based Monitoring and Conservation Promotion Scheme. Julie Ewald, Nevile Kingdon, & Hugues Santin-Janin . 27

Refining the …


Orthotomicus Tridentatus Eggers: Distribution And Biology In Cedar Forests Of Turkey, Mustafa Avci, Oğuzhan Sarikaya Jan 2009

Orthotomicus Tridentatus Eggers: Distribution And Biology In Cedar Forests Of Turkey, Mustafa Avci, Oğuzhan Sarikaya

Turkish Journal of Agriculture and Forestry

Orthotomicus tridentatus Eggers, 1921 (Col.: Curculionidae, Scolytinae) is the most important forest pest of cedar stands in Turkey. Yet, very little is known about its distribution and biology. Therefore, the distribution and biological characteristics of O. tridentatus were studied in the Taurus Mountains in southern Turkey between 2006 and 2008. It was determined to be a species common to all cedar forests. The length of adults was between 2.5 and 3.9 mm and the main galleries were 'S' shaped. O. tridentatus was determined to be a monophagus species for Cedrus libani A. Rich. and as endemic to Turkey. It was …


Revision Of The Ant Genus Crematogaster (Hymenoptera: Formicidae) In North America, Cynthia Ellen Morgan Jan 2009

Revision Of The Ant Genus Crematogaster (Hymenoptera: Formicidae) In North America, Cynthia Ellen Morgan

Open Access Theses & Dissertations

The natural history of thirty-eight species of the genus Crematogaster in North America has been discussed and distribution of specimens mapped. A dichotomous key to the workers of these species has been developed. I hypothesized that the species richness is not as great as previously thought in North America. A taxonomic review of these species has been made with the following changes:

Crematogaster cerasi Fitch 1855 senior synonym of C. browni Buren1968.

C. coarctata Mayr 1870 senior synonym of C. californica Emery 1895, C. mormonum

Emery 1895 and C. colei Buren1968.

C. depilis Wheeler 1919 senior synonym of C. larreae …


Ngasp - The Nematode Genome Annotation Assessment Project, Avril Coghlan, Tristan J. Fiedler, Sheldon J. Mckay, Paul R. Flicek, Todd W. Harris, Darin Blasiar, Lincoln D. Stein Dec 2008

Ngasp - The Nematode Genome Annotation Assessment Project, Avril Coghlan, Tristan J. Fiedler, Sheldon J. Mckay, Paul R. Flicek, Todd W. Harris, Darin Blasiar, Lincoln D. Stein

Biomedical Engineering and Sciences Faculty Publications

While the C. elegans genome is extensively annotated, relatively little information is available for other Caenorhabditis species. The nematode genome annotation assessment project (nGASP) was launched to objectively assess the accuracy of protein-coding gene prediction software in C. elegans, and to apply this knowledge to the annotation of the genomes of four additional Caenorhabditis species and other nematodes. Seventeen groups worldwide participated in nGASP, and submitted 47 prediction sets across 10 Mb of the C. elegans genome. Predictions were compared to reference gene sets consisting of confirmed or manually curated gene models from WormBase. Results: The most accurate gene-finders were …


Estimating Total Phosphorus And Total Suspended Solids Loads From High Frequency Data, Amber Spackman Jones Dec 2008

Estimating Total Phosphorus And Total Suspended Solids Loads From High Frequency Data, Amber Spackman Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Frequently measured turbidity was examined as a surrogate for total phosphorus (TP) and total suspended solids (TSS) loads at two locations in the Little Bear River, Utah, USA. Using regression techniques, equations were developed for TP and TSS as functions of turbidity. The equations accounted for censored data, and additional explanatory variables to represent hydrological conditions were considered for inclusion in the equations. By using the resulting surrogate relationships with high frequency turbidity measurements, high frequency estimates of TP and TSS concentrations were calculated. To examine the effect of sampling frequency, reference loads were determined from the concentration records for …


Community-Based Inquiry Improves Critical Thinking In General Education Biology, Ian J. Quitadamo, Celia L. Faiola, James E. Johnson, Martha J. Kurtz Oct 2008

Community-Based Inquiry Improves Critical Thinking In General Education Biology, Ian J. Quitadamo, Celia L. Faiola, James E. Johnson, Martha J. Kurtz

All Faculty Scholarship for the College of the Sciences

National stakeholders are becoming increasingly concerned about the inability of college graduates to think critically. Research shows that, while both faculty and students deem critical thinking essential, only a small fraction of graduates can demonstrate the thinking skills necessary for academic and professional success. Many faculty are considering nontraditional teaching methods that incorporate undergraduate research because they more closely align with the process of doing investigative science. This study compared a research-focused teaching method called community-based inquiry (CBI) with traditional lecture/laboratory in general education biology to discover which method would elicit greater gains in critical thinking. Results showed significant critical-thinking …


Evolution Of The Holozoan Ribosome Biogenesis Regulon, Seth J. Brown, Michael D. Cole, Albert J. Erives Sep 2008

Evolution Of The Holozoan Ribosome Biogenesis Regulon, Seth J. Brown, Michael D. Cole, Albert J. Erives

Dartmouth Scholarship

The ribosome biogenesis (RiBi) genes encode a highly-conserved eukaryotic set of nucleolar proteins involved in rRNA transcription, assembly, processing, and export from the nucleus. While the mode of regulation of this suite of genes has been studied in the yeast, Saccharomyces cerevisiae, how this gene set is coordinately regulated in the larger and more complex metazoan genomes is not understood. Here we present genome-wide analyses indicating that a distinct mode of RiBi regulation co-evolved with the E(CG)-binding, Myc:Max bHLH heterodimer complex in a stem-holozoan, the ancestor of both Metazoa and Choanoflagellata, the protozoan group most closely related to animals. These …


Lis1 And Ndel1 Influence The Timing Of Nuclear Envelope Breakdown In Neural Stem Cells, Sachin Hebbar, Mariano T. Mesngon, Aimee M. Guillotte, Bhavim Desai, Ramses Ayala, Deanna S. Smith Sep 2008

Lis1 And Ndel1 Influence The Timing Of Nuclear Envelope Breakdown In Neural Stem Cells, Sachin Hebbar, Mariano T. Mesngon, Aimee M. Guillotte, Bhavim Desai, Ramses Ayala, Deanna S. Smith

Faculty Publications

Lis1 and Ndel1 are essential for animal development. They interact directly with one another and with cytoplasmic dynein. The developing brain is especially sensitive to reduced Lis1 or Ndel1 levels, as both proteins influence spindle orientation, neural cell fate decisions, and neuronal migration. We report here that Lis1 and Ndel1 reduction in a mitotic cell line impairs prophase nuclear envelope (NE) invagination (PNEI). This dyneindependent process facilitates NE breakdown (NEBD) and occurs before the establishment of the bipolar spindle. Ndel1 phosphorylation is important for this function, regulating binding to both Lis1 and dynein. Prophase cells in the ventricular zone (VZ) …


Darwin At The Drugstore? Testing The Biological Fitness Of Antibiotic Resistant Bacteria, Alan L. Gillen, Sarah Anderson Jul 2008

Darwin At The Drugstore? Testing The Biological Fitness Of Antibiotic Resistant Bacteria, Alan L. Gillen, Sarah Anderson

Faculty Publications and Presentations

The issue of antibiotic resistance in bacteria is growing. For example, methicillin-resistant Staphylococcus aureus (MRSA) is a leading human pathogen. New strains of MRSA are resistant to methicillin and numerous other antibiotics, placing the patient in significant danger. Indeed, the Centers for Disease Control revealed in 2007 that the number of deaths due to MRSA exceeded that of AIDS in the United States. It is no wonder that antibiotic resistance is one of the most significant and important health care issues. The ability of bacterial pathogens to evade traditional antibiotics is faster than the drug makers’ ability to make new …


The Reproductive Ecology Of Graptemys Geographica In The Central Canal, Kati Keppen Rush May 2008

The Reproductive Ecology Of Graptemys Geographica In The Central Canal, Kati Keppen Rush

Undergraduate Honors Thesis Collection

Life for all organisms involves carefully managing a limited amount of resources. In many cases these resources affect how organisms Jive on a daily basis. In addition to competition from other species, organisms face competition within their own species, populations, and niches. Those individuals that manage their resources effectively will increase their chances of survival, reproduction, and the continuation of their genes in the gene pool. Studies that focus on life history characteristics of organisms aim to understand the mechanisms used by organisms to increase the chances that their genes will remain in thegenepoolpasttheirown Iifetime.Thegoal ofthesemechanisms istoensuresurvival and maximize reproduction. …


Foraging Preference By Wild Deer On Toyon (Heteromeles Arbutifolia) From Santa Catalina Island Versus Malibu, Amelia I. Clark, Brett Smith, Courtney Smith, Stephen D. Davis May 2008

Foraging Preference By Wild Deer On Toyon (Heteromeles Arbutifolia) From Santa Catalina Island Versus Malibu, Amelia I. Clark, Brett Smith, Courtney Smith, Stephen D. Davis

Featured Research

Our group collected samples of Heteromeles Arbutifolia from both Santa Catalina Island and Pepperdine University’s campus in Malibu, CA in order to compare the morphological differences and deer preference between them. In our experiment, we planted the H. Arbutifolia from both locations side by side on a hillside overlooked by the Thorton Administration Center building on Pepperdine’s campus. In the first trial the deer did not consume either of the samples; we believe this was due to the length of time from when the branches were collected from the island to when they were introduced to the deer on campus. …