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Selected Works

2008

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Articles 1 - 30 of 106

Full-Text Articles in Biology

Co-Encapsulation Of Gallium With Gentamicin In Liposomes Enhances Antimicrobial Activity Of Gentamicin Against Pseudomonas Aeruginosa, Majed Halwani, B. Yebio, Zacharias E. Suntres, M. Alipour, Ali Azghani, A. Omri Nov 2008

Co-Encapsulation Of Gallium With Gentamicin In Liposomes Enhances Antimicrobial Activity Of Gentamicin Against Pseudomonas Aeruginosa, Majed Halwani, B. Yebio, Zacharias E. Suntres, M. Alipour, Ali Azghani, A. Omri

Ali Azghani

The aim of this study was to enhance the antimicrobial efficacy of a liposomal gentamicin formulation with gallium metal (Lipo-Ga-GEN) against clinical isolates of Pseudomonas aeruginosa. 

Sputum isolates of P. aeruginosa from cystic fibrosis patients were used to determine the MIC and MBC of Lipo-Ga-GEN. P. aeruginosa biofilms were formed and used to compare the minimum biofilm eradication concentration of the conventional drugs with that of Lipo-Ga-GEN. Quorum sensing (QS) molecule reduction of P. aeruginosa was determined by monitoring N-acyl homoserine lactone production using Agrobacterium tumefaciens reporter strain (A136). Viability of the cultured human lung epithelial cells (A549) was determined …


Distribution Patterns Of Sciurus Niger (Eastern Fox Squirrel) Leaf Nests Within Woodlots Across A Suburban/Urban Landscape, Carmen M. Salsbury Nov 2008

Distribution Patterns Of Sciurus Niger (Eastern Fox Squirrel) Leaf Nests Within Woodlots Across A Suburban/Urban Landscape, Carmen M. Salsbury

Carmen M. Salsbury

To determine habitat characteristics that influence Sciurus niger (Eastern Fox Squirrel) abundance and distribution within a suburban/urban landscape in the midwestern United States, I documented the density and placement of fox squirrel leaf nests in 20 woodlots in the Indianapolis metropolitan area. Marion County, IN. The woodlots varied in size (0.94 to 19.5 ha), approximate age, shape, and degree of isolation from other woodlots and suitable squirrel habitat in the surrounding area. Only 8.0% of nests were located in a tree with another nest, and nests were randomly distributed in all but one woodlot, where they were uniformly dispersed. Nest …


Two Leucine-Rich Repeat Receptor Kinases Mediate Signaling, Linking Cell Wall Biosynthesis And Acc Synthase In Arabidopsis, Shou-Ling Xu, Abidur Rahman, Tobias Baskin, Joseph J. Kieber Nov 2008

Two Leucine-Rich Repeat Receptor Kinases Mediate Signaling, Linking Cell Wall Biosynthesis And Acc Synthase In Arabidopsis, Shou-Ling Xu, Abidur Rahman, Tobias Baskin, Joseph J. Kieber

Tobias Baskin

The plant cell wall is a dynamic structure that changes in response to developmental and environmental cues through poorly understood signaling pathways. We identified two Leu-rich repeat receptor-like kinases in Arabidopsis thaliana that play a role in regulating cell wall function. Mutations in these FEI1 and FEI2 genes (named for the Chinese word for fat) disrupt anisotropic expansion and the synthesis of cell wall polymers and act additively with inhibitors or mutations disrupting cellulose biosynthesis. While FEI1 is an active protein kinase, a kinase-inactive version of FEI1 was able to fully complement the fei1 fei2 mutant. The expansion defect in …


Effect Of Post Composting On Vermicompost Of Spent Mushroom Substrate, Adi Ainurzaman Jamaludin, Noor Zalina Mahmood Nov 2008

Effect Of Post Composting On Vermicompost Of Spent Mushroom Substrate, Adi Ainurzaman Jamaludin, Noor Zalina Mahmood

Adi Ainurzaman Jamaludin

By using Lumbricus rubellus, vermicomposting started after 3 weeks of pre composting. Five treatments in different ratio of cow dung : spent mushroom substrate were prepared as feed materials with four replicates for each treatment namely; 80:20 (T1), 60:40 (T2), 50:50 (T3), 40:60 (T4) and 20:80 (T5). After 7 weeks of vermicomposting, macronutrient elements of vermicompost produced were measured and the process continues with composting when all the earthworms were taken out from the treatments. Macronutrient elements of compost produced were also measured after 20 weeks of composting. The data reveals that 7 weeks for vermicomposting of cow dung and …


Reflections On Recycling, Pollution And History Or, How To Beat The High Cost Of Living, Richard B. Philp Oct 2008

Reflections On Recycling, Pollution And History Or, How To Beat The High Cost Of Living, Richard B. Philp

Richard B. Philp

Lessons learned during the Great Depression and World War II may have to be relearned. The three Rs (reduce, reuse and recycle) were essential then to individual and national survival. A fourth R, repair, was practised as well. These lessons, if relearned, will stand us in good stead when dealing with the current economic climate as well as with problems of pollution and global warming.


Intercourse Between Cell Wall And Cytoplasm Exemplified By Arabinogalactan Proteins And Cortical Microtubules, Azeddine Driouich, Tobias Baskin Oct 2008

Intercourse Between Cell Wall And Cytoplasm Exemplified By Arabinogalactan Proteins And Cortical Microtubules, Azeddine Driouich, Tobias Baskin

Tobias Baskin

How does a plant cell sense and respond to the status of its cell wall? Intercourse between cell wall and cytoplasm has long been supposed to involve arabinogalactan proteins, in part because many of them are anchored to the plasma membrane. Disrupting arabinogalactan proteins has recently been shown to disrupt the array of cortical microtubules present just inside the plasma membrane, implying that microtubules and arabinogalactan proteins interact. In this article, we assess possibilities for how this interaction might be mediated. First, we consider microdomains in the plasma membrane (lipid rafts), which have been alleged to link internal and external …


Demographic Parameters Of Yellowfin Croaker, Umbrina Roncador (Perciformes: Sciaenidae), From The Southern California Bight, Daniel Pondella, John Froeschke, Lynne Wetmore, Eric Miller, Charles Valle, Lea Medeiros Sep 2008

Demographic Parameters Of Yellowfin Croaker, Umbrina Roncador (Perciformes: Sciaenidae), From The Southern California Bight, Daniel Pondella, John Froeschke, Lynne Wetmore, Eric Miller, Charles Valle, Lea Medeiros

Daniel Pondella

The yellowfin croaker, Umbrina roncador Jordan & Gilbert, 1882, is a common nearshore and surf-zone species in the southern California bight. Age was determined for individuals (n = 1,209) using annual increments in otoliths, and size at age was modeled using the von Bertalanffy growth curve (L∞ = 307.754 mm, k = 0.278 yr−1, t0 = −0.995 yr; maximum age = 15 yr). Females (L∞= 313.173 mm, k = 0.307 yr−1, t0 = −0.771 yr) grew significantly faster and larger than males (L∞= 298.886, k = 0.269 yr−1, t0 = −1.072 yr). Age and growth modeling based upon otolith length …


Quorum-Sensing Signals In The Microbial Community Of The Cabbage White Butterfly Larval Midgut, Bradley R. Borlee, Grant D. Geske, Courtney Jaime Robinson, Helen E. Blackwell, Jo Handelsman Sep 2008

Quorum-Sensing Signals In The Microbial Community Of The Cabbage White Butterfly Larval Midgut, Bradley R. Borlee, Grant D. Geske, Courtney Jaime Robinson, Helen E. Blackwell, Jo Handelsman

Courtney Robinson

The overall goal of this study was to examine the role of quorum-sensing (QS) signals in a multispecies microbial community. Toward this aim, we studied QS signals produced by an indigenous member and an invading pathogen of the microbial community of the cabbage white butterfly (CWB) larval midgut (Pieris rapae). As an initial step, we characterized the QS system in Pantoea CWB304, which was isolated from the larval midgut. A luxI homolog, designated panI, is necessary for the production of N-acyl-L-homoserine lactones (AHLs) by Pantoea CWB304. To determine whether AHL signals are exchanged in the alkaline environment of the midgut, …


A Darwinist View Of The Living Constitution, Scott Dodson Sep 2008

A Darwinist View Of The Living Constitution, Scott Dodson

Scott Dodson

The metaphor of a “living" Constitution imports terms from biology into law and, in the process, relies on biology for its meaning. A proper understanding of biology is therefore central to understanding living constitutionalism. Yet despite its rampant use by both opponents and proponents of living constitutionalism, and despite the current fervent debate over whether biology can be useful to the law, no one has evaluated the metaphor from a biological perspective.

This Essay begins that inquiry in an interdisciplinary study of law, science, and philology. The Essay first evaluates the metaphor as it is currently used and concludes that …


Causes Of Mortality Of Wild Birds Submitted To The Charles Darwin Research Station, Santa Cruz, Galápagos, Ecuador From 2002-2004, Patricia Parker, Nicole L. Gottdenker, Timothy Walsh, Gustavo Jiménez-Uzcátegui, Franklin Betancourt, Marilyn Cruz, Catherine Soos, R. Eric Miller Sep 2008

Causes Of Mortality Of Wild Birds Submitted To The Charles Darwin Research Station, Santa Cruz, Galápagos, Ecuador From 2002-2004, Patricia Parker, Nicole L. Gottdenker, Timothy Walsh, Gustavo Jiménez-Uzcátegui, Franklin Betancourt, Marilyn Cruz, Catherine Soos, R. Eric Miller

Patricia Parker

Necropsy findings were reviewed from wild birds submitted to the Charles Darwin Research Station, Santa Cruz Island, Galápagos Archipelago between 2004 and 2006. One hundred and ninety cases from 27 different species were submitted, and 178 of these cases were evaluated grossly or histologically. Trauma and trauma-related deaths (n=141) dominated necropsy submissions. Infectious causes of avian mortality included myiasis due to Philornis sp. (n=6), avian pox (n=1), and schistosomosis (n=1).


Graded Hedgehog And Fibroblast Growth Factor Signaling Independently Regulate Pituitary Cell Fates And Help Establish The Pars Distalis And Pars Intermedia Of The Zebrafish Adenohypophysis, Burcu Guner, A. Tuba Ozacar, Jeanne E. Thomas, Rolf O. Karlstrom Sep 2008

Graded Hedgehog And Fibroblast Growth Factor Signaling Independently Regulate Pituitary Cell Fates And Help Establish The Pars Distalis And Pars Intermedia Of The Zebrafish Adenohypophysis, Burcu Guner, A. Tuba Ozacar, Jeanne E. Thomas, Rolf O. Karlstrom

Rolf O Karlstrom

The vertebrate adenohypophysis forms as a placode at the anterior margin of the neural plate, requiring both hedgehog (Hh) and fibroblast growth factor (Fgf) mediated cell-cell signaling for induction and survival of endocrine cell types. Using small molecule inhibitors to modulate signaling levels during zebrafish development we show that graded Hh and Fgf signaling independently help establish the two subdomains of the adenohypophysis, the anteriorly located pars distalis (PD) and the posterior pars intermedia (PI). High levels of Hh signaling are required for formation of the PD and differentiation of anterior endocrine cell types, whereas lower levels of Hh signaling …


Soluble Factors From Plasmodium Falciparum-Infected Erythrocytes Induce Apoptosis In Human Brain Vascular Endothelial And Neuroglia Cells, Winston A. Anderson Aug 2008

Soluble Factors From Plasmodium Falciparum-Infected Erythrocytes Induce Apoptosis In Human Brain Vascular Endothelial And Neuroglia Cells, Winston A. Anderson

Winston Anderson

The severity of malaria is multi-factorial. It is associated with parasite-induced alteration in pro-inflammatory and anti-inflammatory cytokine and chemokine levels in host serum and cerebrospinal fluid. It is also associated with sequestration and cytoadherence of parasitized erythrocytes (pRBCs) in post-capillary venules and blood-brain barrier (BBB) dysfunction. The role of these factors in development of vascular injury and tissue damage in malaria patients is unclear. While some studies indicate a requirement for pRBC adhesion to vascular endothelial cells (ECs) in brain capillaries to induce apoptosis and BBB damage, others show no role of apoptosis resulting from adhesion of pRBC to EC. …


Impact Of Apoe Deficiency During Synaptic Remodeling In The Mouse Olfactory Bulb, Ikemefuna Nwosu, Salina Gairhe, Robert G. Struble, Britto P. Nathan Aug 2008

Impact Of Apoe Deficiency During Synaptic Remodeling In The Mouse Olfactory Bulb, Ikemefuna Nwosu, Salina Gairhe, Robert G. Struble, Britto P. Nathan

Britto P. Nathan

In this study we examined the role of apoE on the rate of synaptic recovery in the olfactory bulb (OB) following olfactory epithelium (OE) lesioning in mice. We used both immunoblotting and immunohistochemical techniques to compare the density of OB synaptophysin (Syn, a synaptic marker) in apoE-gene deficient/knockout (KO) mice and wild-type (WT) mice following OE lesion. We found that the whole bulb concentrations of Syn, measured by immunoblotting, declined sharply following injury in both WT and KO mice during the degenerative phase (3–7 days). After this initial decline, the Syn concentration gradually increased to normal levels by 56 days …


Biocidal Performance Of Acrylated Glyphosate In A Model Photopolymerizable Coating Formulation, Victoria Piunova, Daniel Berger, Douglas C. Neckers, George Bullerjahn, R. Michael Mckay, Andrei V. Federov Aug 2008

Biocidal Performance Of Acrylated Glyphosate In A Model Photopolymerizable Coating Formulation, Victoria Piunova, Daniel Berger, Douglas C. Neckers, George Bullerjahn, R. Michael Mckay, Andrei V. Federov

George Bullerjahn

Acrylated glyphosate was blended into a model polyolacrylate formulation and copolymerized. The resulting copolymer retains herbicidal activity similar to that of the monomer as indicated by the results of biological tests. No release of biocide from the coating was observed. The potential value of these biologically active acrylic formulations as biofouling compositions has been demonstrated by field trials.


Biocidal Performance Of Acrylated Glyphosate In A Model Photopolymerizable Coating Formulation, Victoria Piunova, Daniel Berger, Douglas C. Neckers, George S. Bullerjahn, Robert Michael Mckay, Andrei V. Federov Aug 2008

Biocidal Performance Of Acrylated Glyphosate In A Model Photopolymerizable Coating Formulation, Victoria Piunova, Daniel Berger, Douglas C. Neckers, George S. Bullerjahn, Robert Michael Mckay, Andrei V. Federov

Robert Michael McKay

Acrylated glyphosate was blended into a model polyolacrylate formulation and copolymerized. The resulting copolymer retains herbicidal activity similar to that of the monomer as indicated by the results of biological tests. No release of biocide from the coating was observed. The potential value of these biologically active acrylic formulations as biofouling compositions has been demonstrated by field trials.


Structure Of A Signal Transduction Regulator, Rack1, From Arabidopsis Thaliana, Hemayet Ullah Jul 2008

Structure Of A Signal Transduction Regulator, Rack1, From Arabidopsis Thaliana, Hemayet Ullah

Hemayet Ullah

The receptor for activated C-kinase 1 (RACK1) is a highly conserved WD40 repeat scaffold protein found in a wide range of eukaryotic species from Chlamydymonas to plants and humans. In tissues of higher mammals, RACK1 is ubiquitously expressed and has been implicated in diverse signaling pathways involving neuropathology, cellular stress, protein translation, and developmental processes. RACK1 has established itself as a scaffold protein through physical interaction with a myriad of signaling proteins ranging from kinases, phosphatases, ion channels, membrane receptors, G proteins, IP3 receptor, and with widely conserved structural proteins associated with the ribosome. In the plant Arabidopsis thaliana, RACK1A …


Unraveling Protein Networks With Power Graph Analysis, Loïc Royer, Matthias Reimann, Bill Andreopoulos, Michael Schroeder Jul 2008

Unraveling Protein Networks With Power Graph Analysis, Loïc Royer, Matthias Reimann, Bill Andreopoulos, Michael Schroeder

William B. Andreopoulos

Networks play a crucial role in computational biology, yet their analysis and representation is still an open problem. Power Graph Analysis is a lossless transformation of biological networks into a compact, less redundant representation, exploiting the abundance of cliques and bicliques as elementary topological motifs. We demonstrate with five examples the advantages of Power Graph Analysis. Investigating protein-protein interaction networks, we show how the catalytic subunits of the casein kinase II complex are distinguishable from the regulatory subunits, how interaction profiles and sequence phylogeny of SH3 domains correlate, and how false positive interactions among high-throughput interactions are spotted. Additionally, we …


African Genetic Diversity: Implications For Human Demographic History, Modern Human Origins, And Complex Disease Mapping, Michael C. Campbell, Sarah A. Tishkoff Jun 2008

African Genetic Diversity: Implications For Human Demographic History, Modern Human Origins, And Complex Disease Mapping, Michael C. Campbell, Sarah A. Tishkoff

Michael C. Campbell

Comparative studies of ethnically diverse human populations, particularly in Africa, are important for reconstructing human evolutionary history and for understanding the genetic basis of phenotypic adaptation and complex disease. African populations are characterized by greater levels of genetic diversity, extensive population substructure, and less linkage disequilibrium (LD) among loci compared to non-African populations. Africans also possess a number of genetic adaptations that have evolved in response to diverse climates and diets, as well as exposure to infectious disease. This review summarizes patterns and the evolutionary origins of genetic diversity present in African populations, as well as their implications for the …


Hydrodynamic Performance Of The Minke Whale (Balaenoptera Acutorostrata) Flipper, L N. Cooper, N Sedano, S Johansson, B May, J D. Brown, C M. Holliday, B W. Kot, Frank E. Fish Jun 2008

Hydrodynamic Performance Of The Minke Whale (Balaenoptera Acutorostrata) Flipper, L N. Cooper, N Sedano, S Johansson, B May, J D. Brown, C M. Holliday, B W. Kot, Frank E. Fish

Frank E. Fish

Minke whales ( Balaenoptera acutorostrata) are the smallest member of balaenopterid whales and little is known of their kinematics during feeding maneuvers. These whales have narrow and elongated flippers that are small relative to body size compared to related species such as right and gray whales. No experimental studies have addressed the hydrodynamic properties of minke whale flippers and their functional role during feeding maneuvers. This study integrated wind tunnel, locomotion and anatomical range of motion data to identify functional parameters of the cambered minke whale flipper. A full-sized cast of a minke whale flipper was used in wind tunnel …


Brazilian Free-Tailed Bats (Tadarida Brasiliensis) As Insect Pest Regulators In Transgenic And Conventional Cotton Crops, P. Federocp, T. G. Hallam, Gary F. Mccracken, S. T. Purucker, W. E. Grant, A. N. Correa-Sandoval, J. K. Westbrook, R. A. Medellin, C. J. Cleveland, C. G. Sansone, J. D. Lopez Jr., M. Betke, A. Moreno-Valdez, T. H. Kunz Jun 2008

Brazilian Free-Tailed Bats (Tadarida Brasiliensis) As Insect Pest Regulators In Transgenic And Conventional Cotton Crops, P. Federocp, T. G. Hallam, Gary F. Mccracken, S. T. Purucker, W. E. Grant, A. N. Correa-Sandoval, J. K. Westbrook, R. A. Medellin, C. J. Cleveland, C. G. Sansone, J. D. Lopez Jr., M. Betke, A. Moreno-Valdez, T. H. Kunz

Gary F. McCracken

During the past 12 000 years agricultural systems have transitioned from natural habitats to conventional agricultural regions and recently to large areas of genetically engineered (GE) croplands. This GE revolution occurred for cotton in a span of slightly more than a decade during which a switch occurred in major cotton production areas from growing 100% conventional cotton to an environment in which 95% transgenics are grown. Ecological interactions between GE targeted insects and other insectivorous insects have been investigated. However, the relationships between ecological functions (such as herbivory and ecosystem transport) and agronomic benefits of avian or mammalian insectivores in …


Rules Of Engagement: Interspecies Interactions That Regulate Microbial Communities, Ainslie Little, Courtney Jaime Robinson, S Brook Peterson, Kenneth F. Raffa, Jo Handelsman May 2008

Rules Of Engagement: Interspecies Interactions That Regulate Microbial Communities, Ainslie Little, Courtney Jaime Robinson, S Brook Peterson, Kenneth F. Raffa, Jo Handelsman

Courtney Robinson

Microbial communities comprise an interwoven matrix of biological diversity modified by physical and chemical variation over space and time. Although these communities are the major drivers of biosphere processes, relatively little is known about their structure and function, and predictive modeling is limited by a dearth of comprehensive ecological principles that describe microbial community processes. Here we discuss working definitions of central ecological terms that have been used in various fashions in microbial ecology, provide a framework by focusing on different types of interactions within communities, review the status of the interface between evolutionary and ecological study, and highlight important …


Dna Inside, Lori B. Andrews May 2008

Dna Inside, Lori B. Andrews

Lori B. Andrews

DNA computers may help scientists overcome the limitations of silicon-based machines, leading to new nano-scale products as well as smart drugs that adjust to their biological environment.


Psf2 Plays Important Roles In Normal Eye Development In Xenopus Laevis, Brian Walter, Kimberly Perry, Lisa Fukui, Erica Malloch, Jason Weaver, Jonathan Henry May 2008

Psf2 Plays Important Roles In Normal Eye Development In Xenopus Laevis, Brian Walter, Kimberly Perry, Lisa Fukui, Erica Malloch, Jason Weaver, Jonathan Henry

Brian Walter

No abstract provided.


Writing Research Proposal: Literature Review And Database Search, Mamoudou H. Dicko Prof. May 2008

Writing Research Proposal: Literature Review And Database Search, Mamoudou H. Dicko Prof.

Pr. Mamoudou H. DICKO, PhD

The maiden proposed research project should demonstrate that the present study will add a significant knowledge on the subject. The main objective of the literature research is to allow that the statement of the research need will clearly establish the objective of the new study.


Life On The Edge: Morphological And Behavioral Adaptations For Survival On Wave-Swept Shores, Luke P. Miller May 2008

Life On The Edge: Morphological And Behavioral Adaptations For Survival On Wave-Swept Shores, Luke P. Miller

Luke P. Miller

Wave-swept rocky shores serve as a home to a great diversity of organisms and are some of the most biologically productive habitats on earth. This burgeoning community exists in spite of the fact that the zone between the high and low tide marks can be one of the most physically harsh environments on earth. Large forces imposed by breaking waves and wide swings in temperature require the organisms living on rocky shores to adapt to a constantly changing environment or risk extirpation by physical forces. I have explored a number of hypothesized adaptations for survival on rocky shores and discuss …


Short Report: Detection Of Plasmodium Falciparum Histidine-Rich Protein Ii In Saliva Of Malaria Patients, Nana Wilson, Andrew A. Adjei, Winston A. Anderson, Stella Baidoo, Jonathan K. Stiles Apr 2008

Short Report: Detection Of Plasmodium Falciparum Histidine-Rich Protein Ii In Saliva Of Malaria Patients, Nana Wilson, Andrew A. Adjei, Winston A. Anderson, Stella Baidoo, Jonathan K. Stiles

Winston Anderson

Detection of Plasmodium falciparum parasites in patients with malaria necessitates drawing blood, which increases the risk of accidental infections and is poorly accepted in communities with blood taboos. Thus, non-invasive, cost-effective malaria tests that minimize the need for blood collection are needed. Plasmodium falciparum histidine-rich protein II (PfHRP II) levels in plasma and saliva were compared in malaria-positive and -negative patients in Ghana. Plasma and saliva obtained from 30 thick-film positive and 10 negative children were evaluated for PfHRP II by ELISA. Among the 30 children with positive blood smear, 16 (53%) were PfHRP II positive in plasma and 13 …


An Allometric Scaling Law For Understanding Mammalian Sleep, Ji-Huan He Apr 2008

An Allometric Scaling Law For Understanding Mammalian Sleep, Ji-Huan He

Ji-Huan He

An allometric scaling law is established for explaining sleep time per day which scales with brain mass. The theoretical prediction agrees well with Savage and West’s experimental data.


Why Are Incubation Periods Longer In The Tropics? A Common-Garden Experiment With House Wrens Reveals It Is All In The Egg, Given Harper, W. Douglas Robinson, John D. Styrsky, Brian J. Payne, Charles F. Thompson Mar 2008

Why Are Incubation Periods Longer In The Tropics? A Common-Garden Experiment With House Wrens Reveals It Is All In The Egg, Given Harper, W. Douglas Robinson, John D. Styrsky, Brian J. Payne, Charles F. Thompson

Given Harper

Incubation periods of Neotropical birds are often longer than those of related species at temperate latitudes. We conducted a common-garden experiment to test the hypothesis that longer tropical incubation periods result from longer embryo development times rather than from different patterns of parental incubation behavior. House wrens, one of few species whose geographic range includes tropical equatorial and temperate high latitudes, have incubation periods averaging 1.2 days longer at tropical latitudes. We incubated eggs of house wrens in Illinois and Panama under identical conditions in mechanical incubators. Even after factoring out differences in egg size, tropical house wrens still required …


Anisotropic Contraction In Forisomes: Simple Models Won't Fit, Winfried Peters, Michael Knoblauch, Stephen Warmann, William Pickard, Amy Shen Mar 2008

Anisotropic Contraction In Forisomes: Simple Models Won't Fit, Winfried Peters, Michael Knoblauch, Stephen Warmann, William Pickard, Amy Shen

Winfried S. Peters

Forisomes are ATP-independent, Ca2+-driven contractile protein bodies acting as reversible valves in the phloem of plants of the legume family. Forisome contraction is anisotropic, as shrinkage in length is associated with radial expansion and vice versa. To test the hypothesis that changes in length and width are causally related, we monitored Ca2+- and pH-dependent deformations in the exceptionally large forisomes of Canavalia gladiata by high-speed photography, and computed time-courses of derived geometric parameters (including volume and surface area). Soybean forisomes, which in the resting state resemble those of Canavalia geometrically but have less than 2% of the volume, were also …


Development Of Genetic And Genomic Research Resources For Brachypodium Distachyon, A New Model System For Grass Crop Research, David F. Garvin, Yonb-Qiang Gu, Robert Hasterok, Samuel P. Hazen, Glyn Jenkins, Todd C. Mockler, Luis A J Mur, John P. Vogel Mar 2008

Development Of Genetic And Genomic Research Resources For Brachypodium Distachyon, A New Model System For Grass Crop Research, David F. Garvin, Yonb-Qiang Gu, Robert Hasterok, Samuel P. Hazen, Glyn Jenkins, Todd C. Mockler, Luis A J Mur, John P. Vogel

Samuel P Hazen

Grass crop genomics research frequently is hindered by large genome sizes and polyploidy. While rice is an attractive system for grass genomics due to its small genome size and available genome sequence, it is not particularly well-suited as a robust model system for all grass crops. The wild grass species Brachypodium distachyon (L.) P. Beauv. (Brachypodium) has recently gained favor as a new model system for grass crop genomics research because it possesses a suite of biological traits desired in a model system. Further, it is more closely related to the large and diverse group of cool season grass crops …