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2014

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Articles 901 - 930 of 1587

Full-Text Articles in Biology

Morphological Divergence Driven By Predation Environment Within And Between Species Of Brachyrhaphis Fishes, Spencer J. Ingley, Eric J. Billman, Mark C. Belk, Jerald B. Johnson Feb 2014

Morphological Divergence Driven By Predation Environment Within And Between Species Of Brachyrhaphis Fishes, Spencer J. Ingley, Eric J. Billman, Mark C. Belk, Jerald B. Johnson

Faculty Publications

Natural selection often results in profound differences in body shape among populations from divergent selective environments. Predation is a well-studied driver of divergence, with predators having a strong effect on the evolution of prey body shape, especially for traits related to escape behavior. Comparative studies, both at the population level and between species, show that the presence or absence of predators can alter prey morphology. Although this pattern is well documented in various species or population pairs, few studies have tested for similar patterns of body shape evolution at multiple stages of divergence within a taxonomic group. Here, we examine …

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Potent Inhibition Of Mandelate Racemase By A Fluorinated Substrate-Product Analogue With A Novel Binding Mode, Mitesh Nagar, Adam D. Lietzan, Martin St. Maurice, Stephen L. Bearne Feb 2014

Potent Inhibition Of Mandelate Racemase By A Fluorinated Substrate-Product Analogue With A Novel Binding Mode, Mitesh Nagar, Adam D. Lietzan, Martin St. Maurice, Stephen L. Bearne

Biological Sciences Faculty Research and Publications

Mandelate racemase (MR) from Pseudomonas putida catalyzes the Mg2+-dependent 1,1-proton transfer that interconverts the enantiomers of mandelate. Because trifluorolactate is also a substrate of MR, we anticipated that replacing the phenyl rings of the competitive, substrate-product analogue inhibitor benzilate (Ki = 0.7 mM) with trifluoromethyl groups might furnish an inhibitor. Surprisingly, the substrate-product analogue 3,3,3-trifluoro-2-hydroxy-2-(trifluoromethyl)propanoate (TFHTP) was a potent competitive inhibitor [Ki = 27 ± 4 μM; cf. Km = 1.2 mM for both (R)-mandelate and (R)-trifluorolactate]. To understand the origins of this high binding affinity, we determined the X-ray crystal structure of the MR–TFHTP complex to 1.68 Å resolution. …

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Insights Into The Development And Evolution Of Exaggerated Traits Using De Novo Transcriptomes Of Two Species Of Horned Scarab Beetles, Ian A. Warren, J. Cristobal Vera, Annika Johns, Robert Zinna, James H. Marden, Douglas J. Emlen, Ian Dworkin, Laura C. Lavine Feb 2014

Insights Into The Development And Evolution Of Exaggerated Traits Using De Novo Transcriptomes Of Two Species Of Horned Scarab Beetles, Ian A. Warren, J. Cristobal Vera, Annika Johns, Robert Zinna, James H. Marden, Douglas J. Emlen, Ian Dworkin, Laura C. Lavine

Biological Sciences Faculty Publications

Scarab beetles exhibit an astonishing variety of rigid exo-skeletal outgrowths, known as ‘‘horns’’. These traits are often sexually dimorphic and vary dramatically across species in size, shape, location, and allometry with body size. In many species, the horn exhibits disproportionate growth resulting in an exaggerated allometric relationship with body size, as compared to other traits, such as wings, that grow proportionately with body size. Depending on the species, the smallest males either do not produce a horn at all, or they produce a disproportionately small horn for their body size. While the diversity of horn shapes and their behavioural ecology …

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Creating Student-¬‐Experts In Hydroecology, Richard Gill Feb 2014

Creating Student-¬‐Experts In Hydroecology, Richard Gill

Journal of Undergraduate Research

The National Research Council, in its report on how people learn, identified key differences between novices and experts (Bransford et al. 2000; Donovan and Bransford 2005). One of the grand challenges of education is to shepherd students through the process of becoming experts. Mentored research experiences are a critical component of this process as students “grow in skills and increase in responsibility” (Mentoring Principle #3) and participate in projects that “extend well beyond the routine” and “[develop] of new concepts of learning” (Mentoring Principle #5). Bransford et al. (2000) emphasized that developing into an expert requires, among other things, (1) …

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Hydroxocobalamin Treatment For Carbon Monoxide Exposures: Characterizing Hemoglobin Changes And Testing For Neurological Sequelae, Leonardo Somera Feb 2014

Hydroxocobalamin Treatment For Carbon Monoxide Exposures: Characterizing Hemoglobin Changes And Testing For Neurological Sequelae, Leonardo Somera

Theses and Dissertations

Prior work in our lab has indicated that reduced Hydroxocobalamin (B12r) can be added to human blood and is able to convert carbon monoxide (CO) into carbon dioxide. This has great potential as a direct antidote to mitigate the toxic effects of CO poisoning which is a public health risk. In the first part of our work, we use highly specific wavelengths of light and Raman spectroscopy to study changes in Carboxyhemoglobin (COHb) between blood treated with oxygen and blood treated with oxygen and B12r in a flowing circuit of blood. Using Raman spectroscopy, we found that the addition of …

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Functionally Diverse Biotin-Dependent Enzymes With Oxaloacetate Decarboxylase Activity, Adam D. Lietzan, Martin St. Maurice Feb 2014

Functionally Diverse Biotin-Dependent Enzymes With Oxaloacetate Decarboxylase Activity, Adam D. Lietzan, Martin St. Maurice

Biological Sciences Faculty Research and Publications

Biotin-dependent enzymes catalyze carboxylation, decarboxylation and transcarboxylation reactions that participate in the primary metabolism of a wide range of organisms. In all cases, the overall reaction proceeds via two half reactions that take place in physically distinct active sites. In the first half-reaction, a carboxyl group is transferred to the 1-N′ of a covalently tethered biotin cofactor. The tethered carboxybiotin intermediate subsequently translocates to a second active site where the carboxyl group is either transferred to an acceptor substrate or, in some bacteria and archaea, is decarboxylated to biotin and CO2 in order to power the export of sodium …

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Direct-To-Consumer Genetic Testing In The College Classroom: Knowledge, Attitudes, And Concerns Of Introductory Biology Students, Nicanor Austriaco Feb 2014

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

Biology Faculty Publications

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

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Byu Microscopy Laboratory /Public School Partnership Curriculum Development, Judy L. Pickett Feb 2014

Byu Microscopy Laboratory /Public School Partnership Curriculum Development, Judy L. Pickett

Journal of Undergraduate Research

For the past five years Dr. John Gardner has been developing a microscopy outreach program for students throughout the state of Utah. I became involved in the program in the fall of 1993 and have been heavily involved in program development since that time.

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Septin Assemblies Form By Diffusion-Driven Annealing On Membranes, Andrew A. Bridges, Huaiying Zhang, Shalin B. Mehta, Patricia Occhipinti, Tomomi Tani, Amy S. Gladfelter Feb 2014

Septin Assemblies Form By Diffusion-Driven Annealing On Membranes, Andrew A. Bridges, Huaiying Zhang, Shalin B. Mehta, Patricia Occhipinti, Tomomi Tani, Amy S. Gladfelter

Dartmouth Scholarship

Septins assemble into filaments and higher-order structures that act as scaffolds for diverse cell functions including cytokinesis, cell polarity, and membrane remodeling. Despite their conserved role in cell organization, little is known about how septin filaments elongate and are knitted together into higher-order assemblies. Using fluorescence correlation spectroscopy, we determined that cytosolic septins are in small complexes, suggesting that septin filaments are not formed in the cytosol. When the plasma membrane of live cells is monitored by total internal reflection fluorescence microscopy, we see that septin complexes of variable size diffuse in two dimensions. Diffusing septin complexes collide and make …

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An Experimental Study Of Strong Reciprocity In Bacteria, R. Inglis, R. Inglis, Stuart West, Angus Buckling Feb 2014

An Experimental Study Of Strong Reciprocity In Bacteria, R. Inglis, R. Inglis, Stuart West, Angus Buckling

Biology Department Faculty Works

Strong reciprocity, whereby cooperators punish non-cooperators, may help to explain the evolutionary success of cooperative behaviours. However, theory suggests that selection for strong reciprocity can depend upon tight genetic linkage between cooperation and punishment, to avoid the strategy being outcompeted by non-punishing cooperators. We tested this hypothesis using experimental populations of the bacterium Pseudomonas aeruginosa, which cooperate by producing iron-scavenging siderophores and, in this context, punish non-cooperators with toxins. Consistent with theory, we show that cooperative punishers can indeed invade cheats, but only when the traits are tightly linked. These results emphasize that punishment is only likely to be favoured …

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Variable Facial Plumage In Juvenile Cliff Swallows: A Potential Offspring Recognition Cue?, Allison E. Johnson, Steven Freedberg Feb 2014

Variable Facial Plumage In Juvenile Cliff Swallows: A Potential Offspring Recognition Cue?, Allison E. Johnson, Steven Freedberg

School of Biological Sciences: Faculty Publications

Although the ability to recognize related offspring is essential in the evolution of social behavior, the cues that birds use to identify their own offspring are not fully understood. The Cliff Swallow (Petrochelidon pyrrhonota) is a highly social species that nests in large colonies and exhibits a high incidence of both conspecific brood parasitism and extrapair fertilization, behaviors that can potentially lead to parents investing energy and resources in unrelated offspring, which reduces the parents’ genetic fitness. Because parents continue to feed offspring after they leave the nest, parents also risk investing in unrelated offspring by misidentifying their …

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A Broadly Implementable Research Course In Phage Discovery And Genomics For First-Year Undergraduate Students, Tuajuanda C. Jordan, Sandra H. Burnett, Susan Carson, Steven M. Caruso, Karl Clase, Randall J. Dejong, John J. Dennehy, Dee R. Denver, David Dunbar, Sarah C. R. Elgin, Ann M. Findley, Chris R. Gissendanner, Urszula P. Golebiewska, Nancy Guild, Grant A. Hartzog, Wendy H. Grillo, Gail P. Hollowell, Lee E. Hughes, Allison Johnson, Rodney A. King, Lynn O. Lewis T, Wei Li, Frank Rosenzweig, Michael R. Rubin, Margaret S. Saha, James Sandoz, Christopher D. Shaffer, Barbara Taylor, Louise Temple, Edwin Vazquez, Vassie C. Ware, Lucia P. Barker, Kevin W. Bradley, Deborah Jacobs-Sera, Welkin H. Pope, Daniel A. Russell, Steven G. Cresawn, David Lopatto, Cheryl P. Bailey, Graham F. Hatfull Feb 2014

A Broadly Implementable Research Course In Phage Discovery And Genomics For First-Year Undergraduate Students, Tuajuanda C. Jordan, Sandra H. Burnett, Susan Carson, Steven M. Caruso, Karl Clase, Randall J. Dejong, John J. Dennehy, Dee R. Denver, David Dunbar, Sarah C. R. Elgin, Ann M. Findley, Chris R. Gissendanner, Urszula P. Golebiewska, Nancy Guild, Grant A. Hartzog, Wendy H. Grillo, Gail P. Hollowell, Lee E. Hughes, Allison Johnson, Rodney A. King, Lynn O. Lewis T, Wei Li, Frank Rosenzweig, Michael R. Rubin, Margaret S. Saha, James Sandoz, Christopher D. Shaffer, Barbara Taylor, Louise Temple, Edwin Vazquez, Vassie C. Ware, Lucia P. Barker, Kevin W. Bradley, Deborah Jacobs-Sera, Welkin H. Pope, Daniel A. Russell, Steven G. Cresawn, David Lopatto, Cheryl P. Bailey, Graham F. Hatfull

Biological Sciences Faculty Publications

Engaging large numbers of undergraduates in authentic scientific discovery is desirable but difficult to achieve. We have developed a general model in which faculty and teaching assistants from diverse academic institutions are trained to teach a research course for first-year undergraduate students focused on bacteriophage discovery and genomics. The course is situated within a broader scientific context aimed at understanding viral diversity, such that faculty and students are collaborators with established researchers in the field. The Howard Hughes Medical Institute (HHMI) Science Education Alliance Phage Hunters Advancing Genomics and Evolutionary Science (SEA-PHAGES) course has been widely implemented and has been …

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Examining Historical And Current Mixed-Severity Fire Regimes In Ponderosa Pine And Mixed-Conifer Forests Of Western North America, Dennis C. Odion, Chad T. Hanson, Andre Arsenault, William L. Baker, Dominick A. Dellasala, Richard L. Hutto, Walt Klenner, Max A. Moritz, Rosemary L. Sherriff, Thomas T. Veblen, Mark A. Williams Feb 2014

Examining Historical And Current Mixed-Severity Fire Regimes In Ponderosa Pine And Mixed-Conifer Forests Of Western North America, Dennis C. Odion, Chad T. Hanson, Andre Arsenault, William L. Baker, Dominick A. Dellasala, Richard L. Hutto, Walt Klenner, Max A. Moritz, Rosemary L. Sherriff, Thomas T. Veblen, Mark A. Williams

Biological Sciences Faculty Publications

There is widespread concern that fire exclusion has led to an unprecedented threat of uncharacteristically severe fires in ponderosa pine (Pinus ponderosa Dougl. ex. Laws) and mixed-conifer forests of western North America. These extensive montane forests are considered to be adapted to a low/moderate-severity fire regime that maintained stands of relatively old trees. However, there is increasing recognition from landscape-scale assessments that, prior to any significant effects of fire exclusion, fires and forest structure were more variable in these forests. Biota in these forests are also dependent on the resources made available by higher-severity fire. A better understanding of …

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Host Specificity And Co-Speciation In Avian Haemosporidia In The Western Cape, South Africa, Sharon Okanga, Graeme S. Cumming, Philip A.R. Hockey, Lisa Nupen, Jeffrey L. Peters Feb 2014

Host Specificity And Co-Speciation In Avian Haemosporidia In The Western Cape, South Africa, Sharon Okanga, Graeme S. Cumming, Philip A.R. Hockey, Lisa Nupen, Jeffrey L. Peters

Biological Sciences Faculty Publications

Host and pathogen ecology are often closely linked, with evolutionary processes often leading to the development of host specificity traits in some pathogens. Host specificity may range from ‘generalist’, where pathogens infect any available competent host; to ‘specialist’, where pathogens repeatedly infect specific host species or families. Avian malaria ecology in the region remains largely unexplored, despite the presence of vulnerable endemic avian species. We analysed the expression of host specificity in avian haemosporidia, by applying a previously developed host specificity index to lineages isolated from wetland passerines in the Western Cape, South Africa. Parasite lineages were isolated using PCR …

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Deletion Of Aif1 But Not Of Yca1/Mca1 Protects Saccharomyces Cerevisiae And Candida Albicans Cells From Caspofungin-Induced Programmed Cell Death, Nicanor Austriaco, Christopher Chin, Faith Donaghey, Kathrine Helming, Morgan Mccarthy, Stephen Rogers Feb 2014

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

Biology Faculty Publications

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

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A Dichotomous Key For The Identification Of Nine Salmonids Of The Inland Northwest Using Six Diagnostic Skull Bones : And Associated Equations To Estimate Total Length And Weight From Bones Ingested By Piscivores Or Found In Archeological Sites, Aaron G. Stroud, Allan T. Scholz, Fisheries Research Center (Cheney, Wash.) Feb 2014

A Dichotomous Key For The Identification Of Nine Salmonids Of The Inland Northwest Using Six Diagnostic Skull Bones : And Associated Equations To Estimate Total Length And Weight From Bones Ingested By Piscivores Or Found In Archeological Sites, Aaron G. Stroud, Allan T. Scholz, Fisheries Research Center (Cheney, Wash.)

Biology Faculty Publications

No abstract provided.

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Biogeomorphology Of A Mojave Desert Landscape — Configurations And Feedbacks Of Abiotic And Biotic Land Surfaces During Landform Evolution, Rebecca E. Drenovsky, N. Pietrasiak, L. S. Santiago, R. C. Graham Feb 2014

Biogeomorphology Of A Mojave Desert Landscape — Configurations And Feedbacks Of Abiotic And Biotic Land Surfaces During Landform Evolution, Rebecca E. Drenovsky, N. Pietrasiak, L. S. Santiago, R. C. Graham

Biology

Terrestrial ecosystems can be more holistically understood by investigating the morphology of landscape mosaics, the assemblage of their ecological communities, and the linkages and feedbacks between the mosaics and communities. The overarching objectives of this study were to: (1) study the abiotic and biotic configurations of landform units as mosaics within a Mojave Desert chronosequence; and (2) elucidate their potential feedbacks, interactions, and dynamics during landform evolution. Seven landform units distributed over three geomorphic ages were identified, including: young bars and swales; intermediate-aged flattened bars, flattened swales, and bioturbation units; and old desert pavements and shrub zones. These landform units …

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Invasive Plant Erodes Local Song Diversity In A Migratory Passerine, Yvette K. Ortega, Aubree Benson, Erick Greene Feb 2014

Invasive Plant Erodes Local Song Diversity In A Migratory Passerine, Yvette K. Ortega, Aubree Benson, Erick Greene

Biological Sciences Faculty Publications

Exotic plant invasions threaten ecosystems globally, but we still know little about the specific consequences for animals. Invasive plants can alter the quality of breeding habitat for songbirds, thereby impacting important demographic traits such as dispersal, philopatry, and age structure. These demographic effects may in turn alter song-learning conditions to affect song structure and diversity. We studied Chipping Sparrows (Spizella passerina) breeding in six savannas that were either dominated by native vegetation or invaded by spotted knapweed (Centaurea stoebe), an exotic forb known to diminish food resources and reproductive success. Here, we report that the prevalence of older birds was …

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New Genera And Species Of Neotropical Exosternini (Coleoptera, Histeridae), Michael S. Caterino, Alexey K. Tishechkin Feb 2014

New Genera And Species Of Neotropical Exosternini (Coleoptera, Histeridae), Michael S. Caterino, Alexey K. Tishechkin

Publications

We describe the following 8 new genera and 23 new species of Neotropical Exosternini. Conocassis gen. n. (Conocassis minor sp. n. [type species], Conocassis dromedaria sp. n., Conocassis trisulcata sp. n., and Conocassis invaginata sp. n.), Enkyosoma gen. n. (Enkyosoma rockwelli sp. n.), Pluricosta gen. n. (Pluricosta onthophiloides sp. n.), Pyxister gen. n. (Pyxister devorator sp. n. [type species] and Pyxister labralis sp. n.), Chapischema gen. n. (Chapischema doppelganger sp. n.), Scaptorus gen. n. (Scaptorus pyramus sp. n.), Lacrimorpha gen. n. (Lacrimorpha glabra sp. n. [type species], Lacrimorpha balbina sp. n., Lacrimorpha subdepressa sp. n., and Lacrimorpha acuminata sp. n.), …

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Environews #8, Richard Philp Feb 2014

Environews #8, Richard Philp

Data and Test Instruments

Crows are clever, sea turtles are shocked and tuna are heartsick..

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Trans Fatty Acids – A Risk Factor For Cardiovascular Disease, Mohammad Perwaiz Iqbal Feb 2014

Trans Fatty Acids – A Risk Factor For Cardiovascular Disease, Mohammad Perwaiz Iqbal

Department of Biological & Biomedical Sciences

Trans fatty acids (TFA) are produced either by hydrogenation of unsaturated oils or by biohydrogenation in the stomach of ruminant animals. Vanaspati ghee and margarine have high contents of TFA. A number of studies have shown an association of TFA consumption and increased risk of cardiovascular disease (CVD). This increased risk is because TFA increase the ratio of LDL cholesterol to HDL cholesterol. Food and Agriculture Organization of the United Nations and World Health Organization have come up with the recommendation that the contents of TFA in human dietary fat should be reduced to less than 4%. There is high …

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A Broadly Implementable Research Course In Phage Discovery And Genomics For First-Year Undergraduate Students, Tuajuanda Jordan, Sandra Burnett, Susan Carson, Steven Caruso, Kari Clase, Randall Dejong, John Dennehy, Dee Denver, David Dunbar, Sarah C.R. Elgin, Ann Findley, Chris Gissendanner, Urszula Golebiewska, Nancy Guild, Grant Hartzog, Wendy Grillo, Gail Hollowell, Lee Hughes, Allison Johnson, Rodney King, Lynn Lewis, Wei Li, Frank Rosenzweig, Michael Rubin, Margaret Saha, James Sandoz, Christopher Shaffer, Barbara Taylor, Louise Temple, Edwin Vazquez, Vassie Ware, Lucia Barker, Kevin Bradley, Deborah Jacobs-Sera, Welkin Pope, Daniel Russell, Steven Cresawn, David Lopatto, Cherly Bailey, Graham Hatfull Feb 2014

A Broadly Implementable Research Course In Phage Discovery And Genomics For First-Year Undergraduate Students, Tuajuanda Jordan, Sandra Burnett, Susan Carson, Steven Caruso, Kari Clase, Randall Dejong, John Dennehy, Dee Denver, David Dunbar, Sarah C.R. Elgin, Ann Findley, Chris Gissendanner, Urszula Golebiewska, Nancy Guild, Grant Hartzog, Wendy Grillo, Gail Hollowell, Lee Hughes, Allison Johnson, Rodney King, Lynn Lewis, Wei Li, Frank Rosenzweig, Michael Rubin, Margaret Saha, James Sandoz, Christopher Shaffer, Barbara Taylor, Louise Temple, Edwin Vazquez, Vassie Ware, Lucia Barker, Kevin Bradley, Deborah Jacobs-Sera, Welkin Pope, Daniel Russell, Steven Cresawn, David Lopatto, Cherly Bailey, Graham Hatfull

Biology Faculty Research

Engaging large numbers of undergraduates in authentic scientific discovery is desirable but difficult to achieve. We have developed a general model in which faculty and teaching assistants from diverse academic institutions are trained to teach a research course for first-year undergraduate students focused on bacteriophage discovery and genomics. The course is situated within a broader scientific context aimed at understanding viral diversity, such that faculty and students are collaborators with established researchers in the field. The Howard Hughes Medical Institute (HHMI) Science Education Alliance Phage Hunters Advancing Genomics and Evolutionary Science (SEA-PHAGES) course has been widely implemented and has been …

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Successful Treatment Of An Mtbe-Impacted Aquifer Using A Bioreactor Self-Colonized By Native Aquifer Bacteria, Kristin A. Hicks, Radomir Schmidt, Michael G. Nickelsen, Susan L. Boyle, Jeffrey M. Baker, Paul M. Tornatore, Krassimira R. Hristova, Kate M. Scow Feb 2014

Successful Treatment Of An Mtbe-Impacted Aquifer Using A Bioreactor Self-Colonized By Native Aquifer Bacteria, Kristin A. Hicks, Radomir Schmidt, Michael G. Nickelsen, Susan L. Boyle, Jeffrey M. Baker, Paul M. Tornatore, Krassimira R. Hristova, Kate M. Scow

Biological Sciences Faculty Research and Publications

A field-scale fixed bed bioreactor was used to successfully treat an MTBE-contaminated aquifer in North Hollywood, CA without requiring inoculation with introduced bacteria. Native bacteria from the MTBE-impacted aquifer rapidly colonized the bioreactor, entering the bioreactor in the contaminated groundwater pumped from the site, and biodegraded MTBE with greater than 99 % removal efficiency. DNA sequencing of the 16S rRNA gene identified MTBE-degrading bacteria Methylibium petroleiphilum in the bioreactor. Quantitative PCR showed M. petroleiphilum enriched by three orders of magnitude in the bioreactor above densities pre-existing in the groundwater. Because treatment was carried out by indigenous rather than introduced organisms, …

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Sorting Out The Trash: The Spatial Nature Of Eukaryotic Protein Quality Control, Emily M. Sontag, Willianne Im Vonk, Judith Frydman Feb 2014

Sorting Out The Trash: The Spatial Nature Of Eukaryotic Protein Quality Control, Emily M. Sontag, Willianne Im Vonk, Judith Frydman

Biological Sciences Faculty Research and Publications

Failure to maintain protein homeostasis is associated with aggregation and cell death, and underlies a growing list of pathologies including neurodegenerative diseases, aging, and cancer. Misfolded proteins can be toxic and interfere with normal cellular functions, particularly during proteotoxic stress. Accordingly, molecular chaperones, the ubiquitin-proteasome system (UPS) and autophagy together promote refolding or clearance of misfolded proteins. Here we discuss emerging evidence that the pathways of protein quality control (PQC) are intimately linked to cell architecture, and sequester proteins into spatially and functionally distinct PQC compartments. This sequestration serves a number of functions, including enhancing the efficiency of quality control; …

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Riverine Macrosystems Ecology: Sensitivity, Resistance, And Resilience Of Whole River Basins With Human Alterations, Kevin E. Mccluney, N Leroy Poff, Margaret A. Palmer, James H. Thorp, Geoffrey C. Poole, Bradley S. Williams, Michael R. Williams, Jill S. Baron Feb 2014

Riverine Macrosystems Ecology: Sensitivity, Resistance, And Resilience Of Whole River Basins With Human Alterations, Kevin E. Mccluney, N Leroy Poff, Margaret A. Palmer, James H. Thorp, Geoffrey C. Poole, Bradley S. Williams, Michael R. Williams, Jill S. Baron

Biological Sciences Faculty Publications

Riverine macrosystems are described here as watershed-scale networks of connected and interacting riverine and upland habitat patches. Such systems are driven by variable responses of nutrients and organisms to a suite of global and regional factors (eg climate, human social systems) interacting with finer-scale variations in geology, topography, and human modifications. We hypothesize that spatial heterogeneity, connectivity, and asynchrony among these patches regulate ecological dynamics of whole networks, altering system sensitivity, resistance, and resilience. Long-distance connections between patches may be particularly important in riverine macrosystems, shaping fundamental system properties. Furthermore, the type, extent, intensity, and spatial configuration of human activities …

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A Distinct Type Of Heterochromatin At The Telomeric Region Of The Drosophila Melanogaster Y Chromosome, Ruth Nan, Sidney Wang, Maria Accardo, Monica F. Sentmanat, Patrizio Dimitri, Sarah C.R. Elgin Feb 2014

A Distinct Type Of Heterochromatin At The Telomeric Region Of The Drosophila Melanogaster Y Chromosome, Ruth Nan, Sidney Wang, Maria Accardo, Monica F. Sentmanat, Patrizio Dimitri, Sarah C.R. Elgin

Biology Faculty Research

Heterochromatin assembly and its associated phenotype, position effect variegation (PEV), provide an informative system to study chromatin structure and genome packaging. In the fruit fly Drosophila melanogaster, the Y chromosome is entirely heterochromatic in all cell types except the male germline; as such, Y chromosome dosage is a potent modifier of PEV. However, neither Y heterochromatin composition, nor its assembly, has been carefully studied. Here, we report the mapping and characterization of eight reporter lines that show male-specific PEV. In all eight cases, the reporter insertion sites lie in the telomeric transposon array (HeT-A and TART-B2 homologous repeats) of the …

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Differential Resource Allocation Of Black Mustard Plants (Brassica Nigra L.) With Proximity To Black Walnut Trees (Jug/Ans Californica L.) In A Southern California Riparian Ecosystem, Victor D. Carmona-Galindo, Matt Cronrod, Kellyanne Gold Feb 2014

Differential Resource Allocation Of Black Mustard Plants (Brassica Nigra L.) With Proximity To Black Walnut Trees (Jug/Ans Californica L.) In A Southern California Riparian Ecosystem, Victor D. Carmona-Galindo, Matt Cronrod, Kellyanne Gold

Biology Faculty Works

The invasive forb Brassica nigra (black mustard) and the native tree Jug/ans californica (black walnut) are allelopathic species that suppress the growth of neighboring plants. This study evaluates how allocation to root, reproductive, and photosynthetic biomass in B. nigra was affected with proximity to J. califomica. We hypothesized that a joint suppressive effect would lead to lower root biomass allocation in B. nigra near J. californica due to reduced interspecific competition. Our results indicate that B. nigra plants growing near J. califomica had significantly lower root : total biomass ratios, and provide insights into how to effectively control this invasive …

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Internet Reviews: The Global Biodiversity Information Facility, John Creech Feb 2014

Internet Reviews: The Global Biodiversity Information Facility, John Creech

Library Scholarship

This column comprises a review of the Global Biodiversity Information Facility (GBIF) portal, which is maintained by some 52 participating countries and dozens of scientific organizations. The GBIF provides access to approximately 417 million individual occurrences of organisms. It is recommended for serious students, faculty instructors and research scientists.

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Tribute To Tinbergen: The Place Of Animal Behavior In Biology, Joan E. Strassmann Feb 2014

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

Biology Faculty Research

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

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Comparative Modeling And Functional Characterization Of Two Enzymes Of The Cyclooxygenase Pathway In Drosophila Melanogaster, Yan Qi Feb 2014

Comparative Modeling And Functional Characterization Of Two Enzymes Of The Cyclooxygenase Pathway In Drosophila Melanogaster, Yan Qi

Dissertations, Theses, and Capstone Projects

Eicosanoids are biologically active molecules oxygenated from twenty carbon polyunsaturated fatty acids. Natural eicosanoids exert potent biological effects in humans, and a great deal of pharmaceutical research has led to the discovery of compounds for selective inhibition of specific enzymes in eicosanoid biosynthesis. Coupled with different receptors, eicosanoids mediate various physiological and pathophysiological processes, including fever generation, pain response, vasoconstriction, vasodilation, platelet aggregation, platelet declumping, body temperature maintenance and sleep-wake cycle regulation. In mammals, the eicosanoid biosynthesis has three pathways: the cyclooxygenase (COX) pathway, the lipoxygenase (LOX) pathway and the epoxygenase pathway. The COX pathway synthesizes prostanoids, which are important …

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