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2005

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Estimating Surface Wetness On Plants, R.D. Magarey, R.C. Seem, A. Weiss, T. Gillespie, L. Huber Jan 2005

Estimating Surface Wetness On Plants, R.D. Magarey, R.C. Seem, A. Weiss, T. Gillespie, L. Huber

Department of Agronomy and Horticulture: Faculty Publications

Plant surface (leaf, stem, petiole, etc) wetness or leaf wetness is an important agricultural weather variable for the prediction of plant diseases (Yarwood, 1978). The estimation of surface wetness has received considerable attention from a diverse group of scientists but unfortunately, no standard for measuring surface wetness has been widely accepted. Since surface wetness is not a true meteorological variable, as is temperature or precipitation, its measurement has not been routinely made as part of a general observation program by most national meteorological agencies. The main problem of not observing surface wetness on a routine basis has been the lack …

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Nematode-Induced Changes Of Transporter Gene Expression In Arabidopsis Roots, Ulrich Z. Hammes, Daniel P. Schachtman, R. Howard Berg, Erik Nielsen, Wolfgang Koch, Lauren M. Mcintyre, Christopher G. Taylor Jan 2005

Nematode-Induced Changes Of Transporter Gene Expression In Arabidopsis Roots, Ulrich Z. Hammes, Daniel P. Schachtman, R. Howard Berg, Erik Nielsen, Wolfgang Koch, Lauren M. Mcintyre, Christopher G. Taylor

Department of Agronomy and Horticulture: Faculty Publications

Root-knot plant-parasitic nematodes (Meloidogyne spp.) account for much of the damage inflicted to plants by nematodes. The feeding sites of these nematodes consist of “giant” cells, which have characteristics of transfer cells found in other parts of plants. Increased transport activity across the plasma membrane is a hallmark of transfer cells, and giant cells provide nutrition for nematodes; therefore, we initiated a study to identify the transport processes that contribute to the development and function of nematode- induced feeding sites. The study was conducted over a 4-week period, during which time the large changes in the development of giant …

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Self-Assembly Of Nanoparticles On Live Bacterium: An Avenue To Fabricate Electronic Devices, Ravi F. Saraf, Vikas Berry Jan 2005

Self-Assembly Of Nanoparticles On Live Bacterium: An Avenue To Fabricate Electronic Devices, Ravi F. Saraf, Vikas Berry

Papers in Nanotechnology

Recently, hybrid structures of microorganisms with inorganic nanoscale moieties have received great interest owing to their potential in fabricating electronic systems. The electronic properties of metal nanoparticles, as a result of the singleelectron transport of current,[1] make them ideal materials for nanodevices. Concomitantly, the nanostructure of microorganisms such as bacteria,[2] viruses,[3, 4] and yeast[5] are attractive scaffolds for the templating of metal nanoparticles through the interactions of the former with surface charges and the affinity of certain metals for specific biological molecules.[2–7] However, the key challenges in building hybrid devices are 1) to pattern nanostructures without destroying the biological construct …

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Crystallization And Preliminary X-Ray Analysis Of Na-Asp-1, A Multi-Domain Pathogenesis-Related-1 Protein From The Human Hookworm Parasite Necator Americanus, Oluwatoyin A. Asojo, Alex Loukas, Mehmet Inan, Rick Barent, Jicai Huang, Brad Plantz, Amber Swanson, Mark Gouthro, Michael M. Meagher, Peter J. Hotez Jan 2005

Crystallization And Preliminary X-Ray Analysis Of Na-Asp-1, A Multi-Domain Pathogenesis-Related-1 Protein From The Human Hookworm Parasite Necator Americanus, Oluwatoyin A. Asojo, Alex Loukas, Mehmet Inan, Rick Barent, Jicai Huang, Brad Plantz, Amber Swanson, Mark Gouthro, Michael M. Meagher, Peter J. Hotez

Department of Chemical and Biomolecular Engineering: Faculty Publications

Human hookworm infection is a major cause of anemia and malnutrition in the developing world. In an effort to control hookworm infection, the Human Hookworm Vaccine Initiative has identified candidate vaccine antigens from the infective larval stage (L3) of the parasite, including a family of pathogenesis-related-1 (PR-1) proteins known as the ancylostoma-secreted proteins (ASPs). The functions of the ASPs are unknown. In addition, it is unclear why some ASPs have one while others have multiple PR-1 domains. There are no known structures of a multi-domain ASP and in an effort to remedy this situation, recombinant Na-ASP-1 has been expressed, …

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Polar Ordering Of Reactive Chromophores In Layer-By-Layer Nonlinear Optical Materials, Kevin Van Cott, James R. Heflin Jr., Harry Gibson, Richey M. Davis Jan 2005

Polar Ordering Of Reactive Chromophores In Layer-By-Layer Nonlinear Optical Materials, Kevin Van Cott, James R. Heflin Jr., Harry Gibson, Richey M. Davis

Department of Chemical and Biomolecular Engineering: Faculty Publications

Thin films exhibiting second-order nonlinear optical (NLO) properties, as well as materials and methods for producing Such films, are provided. The films are formed by depositing, on a Substrate, alternate layers of a polyelectrolyte and a low molecular weight chromophore. The chromophore contains an electrophilic group that reacts with a previously deposited polyelectrolyte, and ionizable groups which present absorption sites for the next polyelectrolyte layer. The films find application in, for example, electro-optic modulators and frequency doubling devices.

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Evaluating Livestock System Environmental Performance With Whole-Farm Nutrient Balance, Richard K. Koelsch Jan 2005

Evaluating Livestock System Environmental Performance With Whole-Farm Nutrient Balance, Richard K. Koelsch

Department of Agricultural and Biological Systems Engineering: Faculty Publications

As a part of the USEPA’s concentrated animal feeding operation (CAFO) final rule, all CAFOs are required to develop and implement a nutrient management plan (NMP). The USEPA’s emphasis on better management of nutrients appropriately targets a critical environmental issue associated with animal production. The concentration of animals in livestock feeding operations, often separate from feed grain production, requires importing of substantial quantities of feed nutrients. Due to the inefficiencies of nutrient utilization in livestock production, quantities of nitrogen (N) and phosphorus (P) in manure greater than can be utilized in local crop production often result. With the focus of …

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Improvement Of Tractor Performance, K. U. Kim, Leonard L. Bashford, Brent T. Sampson Jan 2005

Improvement Of Tractor Performance, K. U. Kim, Leonard L. Bashford, Brent T. Sampson

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Improvement of agricultural tractor performance was analyzed using the data from 926 diesel tractors tested at the Nebraska Tractor Test Laboratory from 1959 through 2002. The performance analysis included the specific volumetric fuel consumption, power per unit weight, traction coefficient, maximum torque rise, and sound level. They were evaluated based on the PTO power level and chassis type of tractor. Some of the results are: (1) The average specific volumetric fuel consumptions for the maximum PTO and drawbar powers increased by 20.5% and 23.4% to 3.47 kW•h/L and 3.01 kW•h/L, respectively, from 1959 through 2002. (2) The average maximum PTO …

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Takagi–Sugeno Fuzzy Modeling Of Skin Permeability, Deepak R. Keshwani, David D. Jones, Rhonda M. Brand Jan 2005

Takagi–Sugeno Fuzzy Modeling Of Skin Permeability, Deepak R. Keshwani, David D. Jones, Rhonda M. Brand

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The skin is a major exposure route for many potentially toxic chemicals. It is, therefore, important to be able to predict the permeability of compounds through skin under a variety of conditions. Available skin permeability databases are often limited in scope and not conducive to developing effective models. This sparseness and ambiguity of available data prompted the use of fuzzy set theory to model and predict skin permeability. Using a previously published database containing 140 compounds, a rule-based Takagi–Sugeno fuzzy model is shown to predict skin permeability of compounds using octanol-water partition coefficient, molecular weight, and temperature as inputs. Model …

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Extraction Of Lipids From Grain Sorghum Ddg, L. Wang, Curtis L. Weller, K. T. Hwang Jan 2005

Extraction Of Lipids From Grain Sorghum Ddg, L. Wang, Curtis L. Weller, K. T. Hwang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Soxhlet and recirculated solvent extraction methods were used to extract lipid materials from grain sorghum DDG. The lipid content in DDG with a moisture content of 6.7% (dry basis) was as high as 9.32% of the dried DDG as determined by Soxhlet extraction with n-hexane. There was a slight increase in the lipid yield from 9.21% to 9.68% when the moisture contents increased from 2.1% to 17.4% (d.b.). Thin-layer chromatography (TLC) analysis showed that the sorghum lipids were composed of triacylglycerols, fatty acids, fatty alcohols, fatty aldehydes, free sterols, wax esters, and steryl esters. A bench-scale recirculated extraction system was …

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Finite Element Modeling And Experimental Validation Of Cooling Rates Of Large Ready-To-Eat Meat Products In Small Meat-Processing Facilities, A. Amézquita, L. Wang, Curtis L. Weller Jan 2005

Finite Element Modeling And Experimental Validation Of Cooling Rates Of Large Ready-To-Eat Meat Products In Small Meat-Processing Facilities, A. Amézquita, L. Wang, Curtis L. Weller

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A two−dimensional axisymmetric transient heat conduction model was developed to simulate air chilling of large ready−to−eat meat products of ellipsoidal shape. A finite element scheme, using 1,600 linear triangular elements with 861 nodes, was implemented in Matlab 6.5 to solve the model. The model considered a variable initial temperature distribution and combined convective, radiative, and evaporative boundary conditions. Predicted values agreed well with experimental data collected in actual processing conditions. Validation of model performance resulted in maximum deviations of 2.54°C and 0.29% for temperature and weight loss histories, respectively. The maximum temperature deviation (2.54°C) occurred at the surface; however, for …

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Policosanol Contents And Compositions In Wax-Like Materials Extracted From Selected Cereals Of Korean Origin, Keum Taek Hwang, Ji Eun Kim, Curtis L. Weller Jan 2005

Policosanol Contents And Compositions In Wax-Like Materials Extracted From Selected Cereals Of Korean Origin, Keum Taek Hwang, Ji Eun Kim, Curtis L. Weller

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Policosanols. long-chained alcohols. have been reported to have beneficial physiological activities. Content and composition of policosanols in wax-like materials extracted from selected cereals of Korean origin were determined. Wax-like materials were extracted using hot hexane. Yields of wax-like materials from unpolished grain sorghum, polished grain sorghum. brown rice. purple rice, wheat, and maize were 223, 37, 33, 61, 10, and 10 mg/100 g of dry kernels, respectively. Policosanol contents, as determined using HPLC, in the wax-like materials from the cereals were 33, 29, 6.0, and 2% (w/w, db), respectively. Major alcohols in the policosanols from grain sorghum were octacosanol and …

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Modeling Of Bubble Growth Dynamics And Nonisothermal Expansion In Starch-Based Foams During Extrusion, Lijun Wang, Girish M. Ganjyal, David D. Jones, Curtis L. Weller, Milford Hanna Jan 2005

Modeling Of Bubble Growth Dynamics And Nonisothermal Expansion In Starch-Based Foams During Extrusion, Lijun Wang, Girish M. Ganjyal, David D. Jones, Curtis L. Weller, Milford Hanna

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A mathematical model was developed to describe expansion phenomena in starch-based foams during extrusion. The model was divided into three parts to describe the microbubble growth dynamics, to couple bubble growth with extrudate expansion, and to describe the macrotransport phenomena in the extrudate, respectively. The differential equations involved in the model were solved by finite element schemes. For validating the model, the predicted radius, density, and residual moisture of final extrudate were compared with experimental data. Standard deviations between the predicted and experimental radius, density, and residual moisture of final extrudates were 16.7%, 11.2%, and 39.3%, respectively. The model was …

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Root Zone Temperatures Of Viburnum Odoratissimum Grown In The Multipot Box System And Conventional Systems: Measurement And Analyses Of Temperature Profiles And Predicting Root Zone Temperatures, Suat Irmak, D. Z. Haman, Ayse Kilic, J. W. Jones, B. Tonkinson, D. Burch, T. H. Yeager, C. Larsen Jan 2005

Root Zone Temperatures Of Viburnum Odoratissimum Grown In The Multipot Box System And Conventional Systems: Measurement And Analyses Of Temperature Profiles And Predicting Root Zone Temperatures, Suat Irmak, D. Z. Haman, Ayse Kilic, J. W. Jones, B. Tonkinson, D. Burch, T. H. Yeager, C. Larsen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This research study evaluates the effectiveness of a recently introduced irrigation- plant production system, multipot box system (MPBS), for moderating root zone temperature (RZT) compared with the conventional nursery containers. The study also deals with the development, calibration, and validation of a series of models that can be used to predict maximum (max) and minimum (min) RZTs using commonly available input variables. The Viburnum odoratissimum (Ker.-gawl.) was used as the test plant. Models were calibrated in the fall growing season and validated during the summer. The RZT was used as the dependent variable while the max and min air temperatures …

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Evaluation Of Toxic Agent Effects On Lung Cells By Fiber Evanescent Wave Spectroscopy, Pierre Lucas, David Lee Coq, Christophe Juncker, Jayne Collier, Dianne E. Boesewetter, Catherine Boussard-Pledel, Bruno Bureau, Mark R. Riley Jan 2005

Evaluation Of Toxic Agent Effects On Lung Cells By Fiber Evanescent Wave Spectroscopy, Pierre Lucas, David Lee Coq, Christophe Juncker, Jayne Collier, Dianne E. Boesewetter, Catherine Boussard-Pledel, Bruno Bureau, Mark R. Riley

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Biochemical changes in living cells are detected using a fiber probe system composed of a single chalcogenide fiber acting as both the sensor and transmission line for infrared optical signals. The signal is collected via evanescent wave absorption along the tapered sensing zone of the fiber. We spectroscopically monitored the effects of the surfactant Triton X-lOO, which serves as a toxic agent simulant on a transformed human lung carcinoma type II epithelial cell line (A549). We observe spectral changes between 2800-3000 cm-1 in four absorptions bands, which are assigned to hydrocarbon vibrations of methylene and methyl groups in membrane lipids. …

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Evaluation Of Methods For Estimating Daily Reference Crop Evapotranspiration At A Site In The Humid Southeast United States, R. E. Yoder, Lameck O. Odhiambo, Wesley C. Wright Jan 2005

Evaluation Of Methods For Estimating Daily Reference Crop Evapotranspiration At A Site In The Humid Southeast United States, R. E. Yoder, Lameck O. Odhiambo, Wesley C. Wright

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Estimated daily reference crop evapotranspiration (ETo) is normally used to determine the water requirement of crops using the crop factor method. Many ETo estimation methods have been developed for different types of climatic data, and the accuracy of these methods varies with climatic conditions. In this study, pair−wise comparisons were made between daily ETo estimated from eight different ETo equations and ETo measured by lysimeter to provide information helpful in selecting an appropriate ETo equation for the Cumberland Plateau located in the humid Southeast United States. Based on the standard error of the …

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Remote Estimation Of Canopy Chlorophyll Content In Crops, Anatoly A. Gitelson, Andrés Viña, Veronica Ciganda, Donald Rundquist, Timothy J. Arkebauer Jan 2005

Remote Estimation Of Canopy Chlorophyll Content In Crops, Anatoly A. Gitelson, Andrés Viña, Veronica Ciganda, Donald Rundquist, Timothy J. Arkebauer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Accurate estimation of spatially distributed chlorophyll content (Chl) in crops is of great importance for regional and global studies of carbon balance and responses to fertilizer (e.g., nitrogen) application. In this paper a recently developed conceptual model was applied for remotely estimating Chl in maize and soybean canopies. We tuned the spectral regions to be included in the model, according to the optical characteristics of the crops studied, and showed that the developed technique allowed accurate estimation of total Chl in both crops, explaining more than 92% of Chl variation. This new technique shows great potential for remotely tracking the …

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Geographic And Ontogenetic Variation In The Contact Calls Of The Kea, Alan B. Bond, Judy Diamond Jan 2005

Geographic And Ontogenetic Variation In The Contact Calls Of The Kea, Alan B. Bond, Judy Diamond

Papers in Behavior in Biological Sciences

Regional and ontogenetic variation in the contact calls of the kea (Nestor notabilis), an omnivorous and socially complex New Zealand parrot, were examined throughout the range of the species. We recorded samples of kee-ah contact calls from sixteen resident adults and eleven juveniles and demonstrated significant differences between age classes in the acoustic form of the vocalization. Canonical correlation analysis revealed a gradient in the form of the kee-ah call in both adults and juveniles along and across the escarpment of the Southern Alps, the primary longitudinal mountain range on the South Island of New Zealand. Although the …

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An Algorithm For Identification Of Bacterial Selenocysteine Insertion Sequence Elements And Selenoprotein Genes, Yan Zhang, Vadim Gladyshev Jan 2005

An Algorithm For Identification Of Bacterial Selenocysteine Insertion Sequence Elements And Selenoprotein Genes, Yan Zhang, Vadim Gladyshev

Department of Biochemistry: Faculty Publications

Motivation: Incorporation of selenocysteine (Sec) into proteins in response to UGA codons requires a cis-acting RNA structure, Sec insertion sequence (SECIS) element. Whereas SECIS elements in Escherichia coli are well characterized, a bacterial SECIS consensus structure is lacking.

Results: We developed a bacterial SECIS consensus model, the key feature of which is a conserved guanosine in a small apical loop of the properly positioned structure. This consensus was used to build a computational tool, bSECISearch, for detection of bacterial SECIS elements and selenoprotein genes in sequence databases. The program identified 96.5% of known selenoprotein genes in completely sequenced bacterial genomes …

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Ph-Dependent Substrate Preference Of Pig Heart Lipoamide Dehydrogenase Varies With Oligomeric State: Response To Mitochondrial Matrix Acidification, Natalia L. Klyachko, Valentina A. Shchedrina, Alexander V. Efimov, Sergey V. Kazakov, Irina G. Gazaryan, Bruce S. Kristal, Abraham M. Brown Jan 2005

Ph-Dependent Substrate Preference Of Pig Heart Lipoamide Dehydrogenase Varies With Oligomeric State: Response To Mitochondrial Matrix Acidification, Natalia L. Klyachko, Valentina A. Shchedrina, Alexander V. Efimov, Sergey V. Kazakov, Irina G. Gazaryan, Bruce S. Kristal, Abraham M. Brown

Department of Biochemistry: Faculty Publications

Cycling of intracellular pH has recently been shown to play a critical role in ischemia-reperfusion injury. Ischemia-reperfusion also leads to mitochondrial matrix acidification and dysfunction. However, the mechanism by which matrix acidification contributes to mitochondrial dysfunction, oxidative stress, and the resultant cellular injury has not been elucidated. We observe pH-dependent equilibria between monomeric, dimeric, and a previously undescribed tetrameric form of pig heart lipoamide dehydrogenase (LADH), a mitochondrial matrix enzyme. Dynamic light scattering studies of native LADH in aqueous solution indicate that lowering pH favors a shift in average molecular mass from higher oligomeric states to monomer. Sedimentation velocity of …

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Regulation Of Enteric Endophytic Bacterial Colonization By Plant Defenses, A. Leonardo Iniguez, Yuemei Dong, Heather D. Carter, Brian M. M. Ahmer, Julie M. Stone, Eric W. Triplett Jan 2005

Regulation Of Enteric Endophytic Bacterial Colonization By Plant Defenses, A. Leonardo Iniguez, Yuemei Dong, Heather D. Carter, Brian M. M. Ahmer, Julie M. Stone, Eric W. Triplett

Department of Biochemistry: Faculty Publications

Bacterial endophytes reside within the interior of plants without causing disease or forming symbiotic structures. Some endophytes, such as Klebsiella pneumoniae 342 (Kp342), enhance plant growth and nutrition. Others, such as Salmonella enterica serovar Typhimurium (S. typhimurium), are human pathogens that contaminate raw produce. Several lines of evidence are presented here to support the hypothesis that plant defense response pathways regulate colonization by endophytic bacteria. An ethyleneinsensitive mutant of Medicago truncatula is hypercolonized by Kp342 compared to the parent genotype. Addition of ethylene, a signal molecule for induced systemic resistance in plants, decreased endophytic colonization in Medicago spp. …

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Phylogenetic Engineering At An Interface Between Large And Small Subunits Imparts Land-Plant Kinetic Properties To Algal Rubisco, Robert J. Spreitzer, Srinivasa R. Peddi, Sriram Satagopan Jan 2005

Phylogenetic Engineering At An Interface Between Large And Small Subunits Imparts Land-Plant Kinetic Properties To Algal Rubisco, Robert J. Spreitzer, Srinivasa R. Peddi, Sriram Satagopan

Department of Biochemistry: Faculty Publications

Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) catalyzes the rate-limiting step of photosynthetic CO2 fixation and, thus, limits agricultural productivity. However, Rubisco enzymes from different species have different catalytic constants. If the structural basis for such differences were known, a rationale could be developed for genetically engineering an improved enzyme. Residues at the bottom of the large-subunit α/β-barrel active site of Rubisco from the green alga Chlamydomonas reinhardtii (methyl-Cys-256, Lys-258, and Ile-265) were previously changed through directed mutagenesis and chloroplast transformation to residues characteristic of land-plant Rubisco (Phe-256, Arg-258, and Val-265). The resultant enzyme has decreases in carboxylation efficiency and CO2/O …

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Roles For Nutrients In Epigenetic Events, Anna M. Oommen, Jacob B. Griffin, Gautam Sarath, Janos Zempleni Jan 2005

Roles For Nutrients In Epigenetic Events, Anna M. Oommen, Jacob B. Griffin, Gautam Sarath, Janos Zempleni

Gautam Sarath Publications

The field of epigenetics is the study of modifications of DNA and DNA-binding proteins that alter the structure of chromatin without altering the nucleotide sequence of DNA; some of these modifications may be associated with heritable changes in gene function. Nutrients play essential roles in the following epigenetic events. First, folate participates in the generation of S-adenosylmethionine, which acts as a methyl donor in the methylation of cytosines in DNA; methylation of cytosines is associated with gene silencing. Second, covalent attachment of biotin to histones (DNA-binding proteins) plays a role in gene silencing and in the cellular response to DNA …

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Homologous And Heterologous Reconstitution Of Golgi To Chloroplast Transport And Protein Import Into The Complex Chloroplasts Of Euglena, Silvia Sláviková, Rostislav Vacula, Zhiwei Fang, Tomoko Ehara, Tetsuaki Osafune, Steven D. Schwartzbach Jan 2005

Homologous And Heterologous Reconstitution Of Golgi To Chloroplast Transport And Protein Import Into The Complex Chloroplasts Of Euglena, Silvia Sláviková, Rostislav Vacula, Zhiwei Fang, Tomoko Ehara, Tetsuaki Osafune, Steven D. Schwartzbach

School of Biological Sciences: Faculty Publications

Euglena complex chloroplasts evolved through secondary endosymbiosis between a phagotrophic trypanosome host and eukaryotic algal endosymbiont. Cytoplasmically synthesized chloroplast proteins are transported in vesicles as integral membrane proteins from the ER to the Golgi apparatus to the Euglena chloroplast. Euglena chloroplast preprotein pre-sequences contain a functional N-terminal ER-targeting signal peptide and a domain having characteristics of a higher plant chloroplast targeting transit peptide, which contains a hydrophobic stop-transfer membrane anchor sequence that anchors the precursor in the vesicle membrane. Pulse-chase subcellular fractionation studies showed that 35S-labeled precursor to the light harvesting chlorophyll a/b binding protein accumulated in the Golgi …

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Indirect Interaction Between Two Native Thistles Mediated By An Invasive Exotic Floral Herbivore, F. Leland Russell, Svata M. Louda Jan 2005

Indirect Interaction Between Two Native Thistles Mediated By An Invasive Exotic Floral Herbivore, F. Leland Russell, Svata M. Louda

School of Biological Sciences: Faculty Publications

Spatial and temporal variation in insect floral herbivory is common and often important. Yet, the determinants of such variation remain incompletely understood. Using 12 years of flowering data and 4 years of biweekly insect counts, we evaluated four hypotheses to explain variation in damage by the Eurasian flower head weevil, Rhinocyllus conicus, to the native North American wavyleaf thistle, Cirsium undulatum. The four factors hypothesized to influence weevil impact were variations in climate, weevil abundance, phenological synchrony, and number of flower heads available, either on wavyleaf thistle or on the other co-occurring, acquired native host plant (Platte thistle, Cirsium …

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First Record Of Drosophila Parthenogenetica And D. Neomorpha, Cardini Group, Heed, 1962 (Drosophila, Drosophilidae), In Brazil, Daniela Cristina De Toni, Jennifer A. Brisson, Paulo R. P. Hofmann, Marlucia Martins, Hope Hollocher Jan 2005

First Record Of Drosophila Parthenogenetica And D. Neomorpha, Cardini Group, Heed, 1962 (Drosophila, Drosophilidae), In Brazil, Daniela Cristina De Toni, Jennifer A. Brisson, Paulo R. P. Hofmann, Marlucia Martins, Hope Hollocher

School of Biological Sciences: Faculty Publications

The cardini group of the Quinaria section of the genus Drosophila is composed of 16 Neotropical species. The two focal species of this report, Drosophila parthenogenetica and D. neomorpha, are included in this group, and are placed in the cardini subgroup with seven other species: D. polymorpha, D. cardinoides, D. cardini, D. neocardini, D. acutilabella, D. bedicheki and D. procardinoides (Heed and Krishnamurthy, 1959; Heed, 1962; Heed and Russell, 1971; Wilder et al., 2003). The group is characterized by medium-sized flies with a shiny thorax (Vilela et al., 2002). Different species of the group display different abdominal pigmentation patterns …

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Abdominal Pigmentation Variation In Drosophila Polymorpha: Geographic Variation In The Trait, And Underlying Phylogeography, Jennifer A. Brisson, Daniela Cristina De Toni, Ian Duncan, Alan R. Templeton Jan 2005

Abdominal Pigmentation Variation In Drosophila Polymorpha: Geographic Variation In The Trait, And Underlying Phylogeography, Jennifer A. Brisson, Daniela Cristina De Toni, Ian Duncan, Alan R. Templeton

School of Biological Sciences: Faculty Publications

Drosophila polymorpha is a widespread species that exhibits abdominal pigmentation variation throughout its range. To gain insight into this variation we combined phenotypic and genotypic data to test a series of nested hypotheses. First, we tested the null hypothesis that geographic variation in pigmentation is due to neutral factors. We used nested clade analysis to examine the distribution of haplotypes from a nuclear and a mitochrondrial locus. Restricted gene flow via isolation by distance, the primary inference of this phylogeographic analysis, was then used to generate and test the hypothesis of increasing average abdominal pigmentation difference with increasing geographic distance. …

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Evaluation Of Ecological Risk To Populations Of A Threatened Plant From An Invasive Biocontrol Insect, Svata M. Louda, Tatyana A. Rand, Amy E. Arnett, A. S. Mcclay, K. Shea, A. Kathryn Mceachern Jan 2005

Evaluation Of Ecological Risk To Populations Of A Threatened Plant From An Invasive Biocontrol Insect, Svata M. Louda, Tatyana A. Rand, Amy E. Arnett, A. S. Mcclay, K. Shea, A. Kathryn Mceachern

School of Biological Sciences: Faculty Publications

Controversy exists over estimation of ecological risk in biological control. At present, the risk to the rare, federally listed Pitcher’s thistle (Cirsium pitcheri) in North America from Rhinocyllus conicus, a biological control weevil now feeding on many native thistles, is unknown. We hypothesized that quantification of host specificity and potential phenological overlap between insect and plant would improve assessment of the magnitude of risk. In laboratory host specificity tests, we found no significant difference in R. conicus feeding or oviposition preference between the rare C. pitcheri and the targeted exotic weed (Carduus nutans) or between …

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Microsatellite Dna Analysis Shows That Greater Sage Grouse Leks Are Not Kin Groups, Robert M. Gibson, Debra Pires, Kathleen S. Delaney, Robert K. Wayne Jan 2005

Microsatellite Dna Analysis Shows That Greater Sage Grouse Leks Are Not Kin Groups, Robert M. Gibson, Debra Pires, Kathleen S. Delaney, Robert K. Wayne

School of Biological Sciences: Faculty Publications

The spectacular social courtship displays of lekking birds are thought to evolve via sexual selection, but this view does not easily explain the participation of many males that apparently fail to mate. One of several proposed solutions to this ‘lek skew paradox’ is that kin selection favors low-ranking males joining leks to increase the fitness of closely related breeders. We investigated the potential for kin selection to operate in leks of the greater sage grouse, Centrocercus urophasianus, by estimating relatedness between lekking males using microsatellite DNA markers. We also calibrated these estimates using data from known families. Mean relatedness within …

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Web-Based Toolkits For Topology Prediction Of Transmembrane Helical Proteins, Fold Recognition, Structure And Binding Scoring, Folding-Kinetics Analysis And Comparative Analysis Of Domain Combinations, Hongyi Zhou, Chi Zhang, Song Liu, Yaoqi Zhou Jan 2005

Web-Based Toolkits For Topology Prediction Of Transmembrane Helical Proteins, Fold Recognition, Structure And Binding Scoring, Folding-Kinetics Analysis And Comparative Analysis Of Domain Combinations, Hongyi Zhou, Chi Zhang, Song Liu, Yaoqi Zhou

School of Biological Sciences: Faculty Publications

We have developed the following web servers for protein structural modeling and analysis at http:// theory.med.buffalo.edu: THUMBUP, UMDHMMTMHP and TUPS, predictors of trans-membrane helical protein topology based on a mean-burial-propensity scale of amino acid residues (THUMBUP), hidden Markov model (UMDHMMTMHP) and their combinations (TUPS); SPARKS 2.0 and SP3, two profile– profile alignment methods, that match input query sequence(s) to structural templates by integrating sequence profile with knowledge-based structural score (SPARKS 2.0) and structure-derived profile (SP3); DFIRE, a knowledge-based potential for scoring free energy of monomers (DMONOMER), loop conformations (DLOOP), mutant stability (DMUTANT) and binding affinity …

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Linking Seed Fate To Natural Dispersal Patterns: Factors Affecting Predation And Scatter-Hoarding Of Virola Calophylla Seeds In Peru, Sabrina E. Russo Jan 2005

Linking Seed Fate To Natural Dispersal Patterns: Factors Affecting Predation And Scatter-Hoarding Of Virola Calophylla Seeds In Peru, Sabrina E. Russo

School of Biological Sciences: Faculty Publications

Natural seed deposition patterns and their effects on post-dispersal seed fate are critical in tropical tree recruitment. Previous research showed that the key dispersal agent of the neotropical tree, Virola calophylla, is the spider monkey (Ateles paniscus). Spider monkeys generate a heterogeneous seed deposition pattern because they scatter-disperse seeds diurnally, whereas they clump-disperse seeds at their sleeping sites. The recruitment consequences of this pattern were investigated using manipulative experiments and observations. Scatter-hoarding by spiny rats (Proechimys spp.) caused little rearrangement of the initial seed deposition pattern because they moved seeds only short distances. Seed survival to …

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