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2012

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Full-Text Articles in Life Sciences

The Evolution Of The Bacterial Luciferase Gene Cassette (Lux) As A Real-Time Bioreporter, Dan Close, Tingting Xu, Abby Smartt, Alexandra Rogers, Robert Crossley, Sarah Price, Steven Ripp, Gary Sayler Jun 2013

The Evolution Of The Bacterial Luciferase Gene Cassette (Lux) As A Real-Time Bioreporter, Dan Close, Tingting Xu, Abby Smartt, Alexandra Rogers, Robert Crossley, Sarah Price, Steven Ripp, Gary Sayler

Gary S. Sayler

The bacterial luciferase gene cassette (lux) is unique among bioluminescent bioreporter systems due to its ability to synthesize and/or scavenge all of the substrate compounds required for its production of light. As a result, the lux system has the unique ability to autonomously produce a luminescent signal, either continuously or in response to the presence of a specific trigger, across a wide array of organismal hosts. While originally employed extensively as a bacterial bioreporter system for the detection of specific chemical signals in environmental samples, the use of lux as a bioreporter technology has continuously expanded over the last ...


A Vision For Future Development In Historic District: Greenway Planning, Green Infrastructure Adaptation And Landscape Design In Historic Districts Of Us And China, Yiwei Huang Dec 2012

A Vision For Future Development In Historic District: Greenway Planning, Green Infrastructure Adaptation And Landscape Design In Historic Districts Of Us And China, Yiwei Huang

Proceedings of the Fábos Conference on Landscape and Greenway Planning

This paper is trying to explore the future development for historic district. “Historic districts” talked in this paper are mostly part of modern cities and have valuable architectures and profuse cultural backgrounds. These historic districts now are legally protected by policies and also by the government, and most of those are involving supremely significant green spaces or greenway systems which can also date hundreds of years ago. However, some of them are still facing serious problem of losing the green patterns of the city and therefore become a scattered puzzle of urban open space system; and some others facing the ...


13c-Metabolic Flux Analysis Of Soybean Somatic Embryos For Identification Of Metabolic Control Points In Developing Seed, Quyen Xuan Truong Dec 2012

13c-Metabolic Flux Analysis Of Soybean Somatic Embryos For Identification Of Metabolic Control Points In Developing Seed, Quyen Xuan Truong

Graduate Theses and Dissertations

Of the world's major agronomic food crops soybeans rank highest in protein content (~40% Dwt) while also containing significant quantities of oil (~20% Dwt). Based on these unique characteristics soy has become a mainstay in world agriculture, providing a protein source for livestock and human nutrition (68% of global vegetable protein meal consumption in 2011) as well as a primary source of vegetable oil (28% of global vegetable oil consumption in 2011; http://www.soystats.com/2012). The value of soy is therefore found both in its oil and protein content and increasing the content of both is therefore ...


The Effect Of Temperature On Seed Quality And Quantity In Crosses Between European (Populus Tremula) And Hybrid Aspens (P. Tremula X P. Tremuloides), L. Koviuranta, T. Latva-Karjanmaa, P. Pulkkinen Dec 2012

The Effect Of Temperature On Seed Quality And Quantity In Crosses Between European (Populus Tremula) And Hybrid Aspens (P. Tremula X P. Tremuloides), L. Koviuranta, T. Latva-Karjanmaa, P. Pulkkinen

Aspen Bibliography

Hybrid aspen (Populus tremula L. Populus tremuloides Michx.) plantations are expanding in Fennoscandia and the Baltic countries; however, the possible effects of plantations on the native European aspen (P. tremula) and the level of gene flow between European and hybrid aspen have not been investigated. We studied seed quantity and quality in intraspecific and interspecific crosses of the European and hybrid aspens over a two year period. In order to study whether elevated temperatures due to climate change would benefit the species differently, we performed the crosses in different temperatures. In both years, interspecific crosses produced more seeds with higher ...


Promoting Amphibian Conservation Through The College Classroom: Detection Of Batrachochytrium Dendrobatidis Among Local Amphibians, Julie Wunder, Noel Lampazzi, Kelsey Acre, Nicholas Bent, Sadie Canter, Alexandra Chapman, Margaret Davies, David Kashan, Jonathan Keiley, Rachel Macintyre, Tamara Milton, Kara Weichler, Matthew Wilson, Mizuki Takahashi Dec 2012

Promoting Amphibian Conservation Through The College Classroom: Detection Of Batrachochytrium Dendrobatidis Among Local Amphibians, Julie Wunder, Noel Lampazzi, Kelsey Acre, Nicholas Bent, Sadie Canter, Alexandra Chapman, Margaret Davies, David Kashan, Jonathan Keiley, Rachel Macintyre, Tamara Milton, Kara Weichler, Matthew Wilson, Mizuki Takahashi

Faculty Journal Articles

Many global amphibian declines have been linked to the fungal pathogen Batrachochytrium dendrobatidis (Bd). The knowledge on Bd distribution provides a fundamental basis for amphibian conservation planning. Yet, such Bd distribution information is currently insufficient, in particular at a regional scale. The college classroom provides an excellent opportunity to expand the knowledge of Bd distribution. Here we provide an example of such research projects to detect Bd prevalence among local amphibians in a college course setting and present the results of work conducted in central Pennsylvania, USA. We collected toe clips and conducted PCR assays of six species, Plethodon cinereus ...


Effect Of Muscle Length On Cross-Bridge Kinetics In Intact Cardiac Trabeculae At Body Temperature, Nima Milani-Nejad, Ying Xu, Jonathan P. Davis, Kenneth S. Campbell, Paul M. L. Janssen Dec 2012

Effect Of Muscle Length On Cross-Bridge Kinetics In Intact Cardiac Trabeculae At Body Temperature, Nima Milani-Nejad, Ying Xu, Jonathan P. Davis, Kenneth S. Campbell, Paul M. L. Janssen

Physiology Faculty Publications

Dynamic force generation in cardiac muscle, which determines cardiac pumping activity, depends on both the number of sarcomeric cross-bridges and on their cycling kinetics. The Frank–Starling mechanism dictates that cardiac force development increases with increasing cardiac muscle length (corresponding to increased ventricular volume). It is, however, unclear to what extent this increase in cardiac muscle length affects the rate of cross-bridge cycling. Previous studies using permeabilized cardiac preparations, sub-physiological temperatures, or both have obtained conflicting results. Here, we developed a protocol that allowed us to reliably and reproducibly measure the rate of tension redevelopment (ktr; which depends on ...


Filtering Efficiency And Feeding Mechanisms Of Daphnia Pulex On Microcystis Aeruginosa And Nannochloropsis, Elizabeth Orlowicz Dec 2012

Filtering Efficiency And Feeding Mechanisms Of Daphnia Pulex On Microcystis Aeruginosa And Nannochloropsis, Elizabeth Orlowicz

Honors Theses and Capstones

The filtering and feeding rate of Daphnia pulex from the Old Durham Reservoir, Durham, NH, were measured to determine the feeding efficiency on different concentrations of non-toxic Nannochloropsis (Class Eustigmatophyceae) and toxigenic cyanobacteria Microcystis aeruginosa. Direct observations of thoracic appendage beats and post-abdominal rejections were also measured at 5*105 and 106 cells mL-1 concentrations of Nannochloropsis and M. aeruginosa to examine the feeding mechanisms of the D. pulex. In the presence of increasing Nannochloropsis concentrations, the filtering rates decreased and the feeding rates increased. When exposed to M. aeruginosa, both the filtering and feeding rates decreased ...


Vesiclepedia: A Compendium For Extracellular Vesicles With Continuous Community Annotation, Hina Kalra, Vivian Budnik, Suresh Mathivanan Dec 2012

Vesiclepedia: A Compendium For Extracellular Vesicles With Continuous Community Annotation, Hina Kalra, Vivian Budnik, Suresh Mathivanan

Neurobiology Publications

Extracellular vesicles (EVs) are membraneous vesicles released by a variety of cells into their microenvironment. Recent studies have elucidated the role of EVs in intercellular communication, pathogenesis, drug, vaccine and gene-vector delivery, and as possible reservoirs of biomarkers. These findings have generated immense interest, along with an exponential increase in molecular data pertaining to EVs. Here, we describe Vesiclepedia, a manually curated compendium of molecular data (lipid, RNA, and protein) identified in different classes of EVs from more than 300 independent studies published over the past several years. Even though databases are indispensable resources for the scientific community, recent studies ...


Molecular Analysis Of The In Situ Growth Rate Of Subsurface Geobacter Species, Dawn Holmes, Ludovic Giloteaux, Melissa Barlett, Milind Chavan, Jessica Smith, Kenneth Williams, Michael Wilkins, Philip Long, Derek Lovley Dec 2012

Molecular Analysis Of The In Situ Growth Rate Of Subsurface Geobacter Species, Dawn Holmes, Ludovic Giloteaux, Melissa Barlett, Milind Chavan, Jessica Smith, Kenneth Williams, Michael Wilkins, Philip Long, Derek Lovley

Microbiology Department Faculty Publication Series

Molecular tools that can provide an estimate of the in situ growth rate of Geobacter species could improve understanding of dissimilatory metal reduction in a diversity of environments. Whole genome microarray analyses of the subsurface isolate, Geobacter uraniireducens, grown under a variety of conditions identified a number of genes that are differentially expressed at different specific growth rates. Expression of two genes encoding ribosomal proteins, rpsC and rplL, were further evaluated with quantitative reverse transcription PCR (qRT-PCR) in cells with doubling times ranging from 6.56 h to 89.28 h. Transcript abundance of rpsC correlated best (r2= 0.90 ...


Measuring Population Transmission Potential For Hiv: An Alternative Metric Of Transmission Risk In Men Who Have Sex With Men (Msm) In The Us, Colleen F. Kelley, Eli S. Rosenberg, Brandon M. O'Hara, Paula M. Frew, Travis Sanchez, John L. Peterson, Carlos Del Rio, Patrick S. Sullivan Dec 2012

Measuring Population Transmission Potential For Hiv: An Alternative Metric Of Transmission Risk In Men Who Have Sex With Men (Msm) In The Us, Colleen F. Kelley, Eli S. Rosenberg, Brandon M. O'Hara, Paula M. Frew, Travis Sanchez, John L. Peterson, Carlos Del Rio, Patrick S. Sullivan

Environmental & Occupational Health Faculty Publications

Background Various metrics for HIV burden and treatment success [e.g. HIV prevalence, community viral load (CVL), population viral load (PVL), percent of HIV-positive persons with undetectable viral load] have important public health limitations for understanding disparities. Methods and Findings Using data from an ongoing HIV incidence cohort of black and white men who have sex with men (MSM), we propose a new metric to measure the prevalence of those at risk of transmitting HIV and illustrate its value. …See full text for complete abstract.


Strand-Specific Libraries For High Throughput Rna Sequencing (Rna-Seq) Prepared Without Poly(A) Selection, Zhao Zhang, William E. Theurkauf, Zhiping Weng, Phillip D. Zamore Dec 2012

Strand-Specific Libraries For High Throughput Rna Sequencing (Rna-Seq) Prepared Without Poly(A) Selection, Zhao Zhang, William E. Theurkauf, Zhiping Weng, Phillip D. Zamore

Program in Bioinformatics and Integrative Biology Publications

BACKGROUND: High throughput DNA sequencing technology has enabled quantification of all the RNAs in a cell or tissue, a method widely known as RNA sequencing (RNA-Seq). However, non-coding RNAs such as rRNA are highly abundant and can consume >70% of sequencing reads. A common approach is to extract only polyadenylated mRNA; however, such approaches are blind to RNAs with short or no poly(A) tails, leading to an incomplete view of the transcriptome. Another challenge of preparing RNA-Seq libraries is to preserve the strand information of the RNAs.

DESIGN: Here, we describe a procedure for preparing RNA-Seq libraries from 1 ...


Orofacial Neuropathic Pain Mouse Model Induced By Trigeminal Inflammatory Compression (Tic) Of The Infraorbital Nerve, Fei Ma, Liping Zhang, Danielle Lyons, Karin N. Westlund Dec 2012

Orofacial Neuropathic Pain Mouse Model Induced By Trigeminal Inflammatory Compression (Tic) Of The Infraorbital Nerve, Fei Ma, Liping Zhang, Danielle Lyons, Karin N. Westlund

Physiology Faculty Publications

BACKGROUND: Trigeminal neuropathic pain attacks can be excruciating for patients, even after being lightly touched. Although there are rodent trigeminal nerve research models to study orofacial pain, few models have been applied to studies in mice. A mouse trigeminal inflammatory compression (TIC) model is introduced here which successfully and reliably promotes vibrissal whisker pad hypersensitivity.

RESULTS: The chronic orofacial neuropathic pain model is induced after surgical placement of chromic gut suture in the infraorbital nerve fissure in the maxillary bone. Slight compression and chemical effects of the chromic gut suture on the portion of the infraorbital nerve contacted cause mild ...


Molecular Analysis Of The In Situ Growth Rate Of Subsurface Geobacter Species, Dawn E. Holmes, Ludovic Giloteaux, Melissa Barlett, Milind A. Chavan, Jessica A. Smith, Kenneth H. Williams, Michael Wilkins, Philip Long, Derek Lovley Dec 2012

Molecular Analysis Of The In Situ Growth Rate Of Subsurface Geobacter Species, Dawn E. Holmes, Ludovic Giloteaux, Melissa Barlett, Milind A. Chavan, Jessica A. Smith, Kenneth H. Williams, Michael Wilkins, Philip Long, Derek Lovley

Derek Lovley

Molecular tools that can provide an estimate of the in situ growth rate of Geobacter species could improve understanding of dissimilatory metal reduction in a diversity of environments. Whole genome microarray analyses of the subsurface isolate, Geobacter uraniireducens, grown under a variety of conditions identified a number of genes that are differentially expressed at different specific growth rates. Expression of two genes encoding ribosomal proteins, rpsC and rplL, were further evaluated with quantitative reverse transcription PCR (qRT-PCR) in cells with doubling times ranging from 6.56 h to 89.28 h. Transcript abundance of rpsC correlated best (r2= 0.90 ...


Piscine Myocarditis Virus (Pmcv) In Wild Atlantic Salmon Salmo Salar, Torstein Tengs Dr. Dec 2012

Piscine Myocarditis Virus (Pmcv) In Wild Atlantic Salmon Salmo Salar, Torstein Tengs Dr.

Dr. Torstein Tengs

Cardiomyopathy syndrome (CMS) is a severe cardiac disease of sea-farmed Atlantic salmon Salmo salar L., but CMS-like lesions have also been found in wild Atlantic salmon. In 2010 a double-stranded RNA virus of the Totiviridae family, provisionally named piscine myocarditis virus (PMCV), was described as the causative agent of CMS. In the present paper we report the first detection of PMCV in wild Atlantic salmon. The study is based on screening of 797 wild Atlantic salmon by real-time RT-PCR. The samples were collected from 35 different rivers along the coast of Norway, and all individuals included in the study were ...


Morc2 Signaling Integrates Phosphorylation-Dependent, Atpase-Coupled Chromatin Remodeling During The Dna Damage Response, Da-Qiang Li, Sujit S. Nair, Kazufumi Ohshiro, Anupam Kumar, Vasudha S. Nair, Suresh B. Pakala, Sirigiri Divijendra Natha Reddy, Rajendra P. Gajula, Jeyanthy Eswaran, L. Aravind, Rakesh Kumar Dec 2012

Morc2 Signaling Integrates Phosphorylation-Dependent, Atpase-Coupled Chromatin Remodeling During The Dna Damage Response, Da-Qiang Li, Sujit S. Nair, Kazufumi Ohshiro, Anupam Kumar, Vasudha S. Nair, Suresh B. Pakala, Sirigiri Divijendra Natha Reddy, Rajendra P. Gajula, Jeyanthy Eswaran, L. Aravind, Rakesh Kumar

Biochemistry and Molecular Medicine Faculty Publications

Chromatin dynamics play a central role in maintaining genome integrity, but how this is achieved remains largely unknown. Here, we report that microrchidia CW-type zinc finger 2 (MORC2), an uncharacterized protein with a derived PHD finger domain and a conserved GHKL-type ATPase module, is a physiological substrate of p21-activated kinase 1 (PAK1), an important integrator of extracellular signals and nuclear processes. Following DNA damage, MORC2 is phosphorylated on serine 739 in a PAK1-dependent manner, and phosphorylated MORC2 regulates its DNA-dependent ATPase activity to facilitate chromatin remodeling. Moreover, MORC2 associates with chromatin and promotes gamma-H2AX induction in a PAK1 phosphorylation-dependent manner ...


Forest Regeneration On The Osa Peninsula, Costa Rica, Manette E. Sandor Dec 2012

Forest Regeneration On The Osa Peninsula, Costa Rica, Manette E. Sandor

Master's Theses

Woody species diversity of secondary forest has the potential to converge with that found in old growth forest. This study is the first to examine multiple aspects of species and reproductive trait diversity, and their relationship to each other, across a successional chronosequence. Species richness and species diversity increases with increasing age of forest. Diaspore size and diversity as well as fruit size generally increased with increasing age of forest, but fruit size diversity did not. Abundance of animal-dispersed species increased whereas wind-dispersed species decreased in abundance over succession. Insect-pollinated individuals were most abundant overall. Diaspore diversity, pollination diversity, and ...


The Rnf Complex Of Clostridium Ljungdahlii Is A Proton-Translocating Ferredoxin: Nad+ Oxidoreductase Essential For Autotrophic Growth, Pier-Luc Tremblay, Tian Zhang, Shabir A. Dar, Ching Leang, Derek Lovley Dec 2012

The Rnf Complex Of Clostridium Ljungdahlii Is A Proton-Translocating Ferredoxin: Nad+ Oxidoreductase Essential For Autotrophic Growth, Pier-Luc Tremblay, Tian Zhang, Shabir A. Dar, Ching Leang, Derek Lovley

Derek Lovley

It has been predicted that the Rnf complex of Clostridium ljungdahlii is a proton-translocating ferredoxin:NAD+ oxidoreductase which contributes to ATP synthesis by an H+-translocating ATPase under both autotrophic and heterotrophic growth conditions. The recent development of methods for genetic manipulation of C. ljungdahlii made it possible to evaluate the possible role of the Rnf complex in energy conservation. Disruption of the C. ljungdahlii rnf operon inhibited autotrophic growth. ATP synthesis, proton gradient, membrane potential, and proton motive force collapsed in the Rnf-deficient mutant with H2 as the electron source and CO2 as the electron acceptor. Heterotrophic growth was ...


The Rnf Complex Of Clostridium Ljungdahlii Is A Proton-Translocating Ferredoxin: Nad+ Oxidoreductase Essential For Autotrophic Growth, Pier-Luc Tremblay, Tian Zhang, Shabir Dar, Ching Leang, Derek Lovley Dec 2012

The Rnf Complex Of Clostridium Ljungdahlii Is A Proton-Translocating Ferredoxin: Nad+ Oxidoreductase Essential For Autotrophic Growth, Pier-Luc Tremblay, Tian Zhang, Shabir Dar, Ching Leang, Derek Lovley

Microbiology Department Faculty Publication Series

It has been predicted that the Rnf complex of Clostridium ljungdahlii is a proton-translocating ferredoxin:NAD+ oxidoreductase which contributes to ATP synthesis by an H+-translocating ATPase under both autotrophic and heterotrophic growth conditions. The recent development of methods for genetic manipulation of C. ljungdahlii made it possible to evaluate the possible role of the Rnf complex in energy conservation. Disruption of the C. ljungdahlii rnf operon inhibited autotrophic growth. ATP synthesis, proton gradient, membrane potential, and proton motive force collapsed in the Rnf-deficient mutant with H2 as the electron source and CO2 as the electron acceptor. Heterotrophic growth was ...


Historical And Contemporary Dna Indicate Fisher Decline And Isolation Occurred Prior To The European Settlement Of California, Jody M. Tucker, Michael K. Schwartz, Richard L. Truex, Kristine L. Pilgrim, Fred W. Allendorf Dec 2012

Historical And Contemporary Dna Indicate Fisher Decline And Isolation Occurred Prior To The European Settlement Of California, Jody M. Tucker, Michael K. Schwartz, Richard L. Truex, Kristine L. Pilgrim, Fred W. Allendorf

Biological Sciences Faculty Publications

Establishing if species contractions were the result of natural phenomena or human induced landscape changes is essential for managing natural populations. Fishers (Martes pennanti) in California occur in two geographically and genetically isolated populations in the northwestern mountains and southern Sierra Nevada. Their isolation is hypothesized to have resulted from a decline in abundance and distribution associated with European settlement in the 1800s. However, there is little evidence to establish that fisher occupied the area between the two extant populations at that time. We analyzed 10 microsatelliteloci from 275 contemporary and 21 historical fisher samples (1880-1920) to evaluate the demographic ...


Ict For Poverty Alleviation In Pacific Island Nations: Study Of Icts4d In Fiji, Deogratias Harorimana, Opeti Rokotuinivono, Emali Sewale, Fane Salaiwai, Marica Naulu, Evangelin Roy Dec 2012

Ict For Poverty Alleviation In Pacific Island Nations: Study Of Icts4d In Fiji, Deogratias Harorimana, Opeti Rokotuinivono, Emali Sewale, Fane Salaiwai, Marica Naulu, Evangelin Roy

Dr Deogratias Harorimana

ICT for Poverty Alleviation in Pacific Island Nations: Study of ICTs4D in Fiji There has been a vague and little knowledge on the role or potential of Information and Communications Technologies (ICTs) in relation to addressing poverty in Fiji. This may be probably due to the newness of the technology in the South Pacific Region as a whole but also probably due to the fact that only 9.7% of the current Fiji 931,000 populations are internet users (ITC Figures 2011). This paper reports on finding how ICTs is contributing towards poverty alleviation in Fiji. On the basis of ...


U.S. Drought Monitor, December 25, 2012, Richard R. Heim Jr. Dec 2012

U.S. Drought Monitor, December 25, 2012, Richard R. Heim Jr.

US Ag in Drought Archive

Drought map of U.S. for December 25, 2012 (12/25/12) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Hay, Cattle, Winter wheat.


The Impact Of Coastal Phytoplankton Blooms On Ocean-Atmosphere Thermal Energy Exchange: Evidence From A Two-Way Coupled Numerical Modeling System, Jason K. Jolliff, Travis A. Smith, Charlie N. Barron, Sergio Derada, Stephanie C. Anderson, Richard W. Gould, Robert A. Arnone Dec 2012

The Impact Of Coastal Phytoplankton Blooms On Ocean-Atmosphere Thermal Energy Exchange: Evidence From A Two-Way Coupled Numerical Modeling System, Jason K. Jolliff, Travis A. Smith, Charlie N. Barron, Sergio Derada, Stephanie C. Anderson, Richard W. Gould, Robert A. Arnone

Faculty Publications

A set of sensitivity experiments are performed with a two-way coupled and nested ocean-atmosphere forecasting system in order to deconvolve how dense phytoplankton stocks in a coastal embayment may impact thermal energy exchange processes. Monterey Bay simulations parameterizing solar shortwave transparency in the surface ocean as an invariant oligotrophic oceanic water type estimate consistently colder sea surface temperature (SST) than simulations utilizing more realistic, spatially varying shortwave attenuation terms based on satellite estimates of surface algal pigment concentration. These SST differences lead to an similar to 88% increase in the cumulative turbulent thermal energy transfer from the ocean to the ...


Chronic Stress Elevates Telomerase Activity In Rats, Annaliese K. Beery, Jue Lin, Joshua S. Biddle, Darlene D. Francis, Elizabeth H. Blackburn, Elissa S. Epel Dec 2012

Chronic Stress Elevates Telomerase Activity In Rats, Annaliese K. Beery, Jue Lin, Joshua S. Biddle, Darlene D. Francis, Elizabeth H. Blackburn, Elissa S. Epel

Neuroscience: Faculty Publications

The enzyme telomerase lengthens telomeres—protective structures containing repetitive DNA sequences at chromosome ends. Telomere shortening is associated with diseases of ageing in mammals. Chronic stress has been related to shorter immune-cell telomeres, but telomerase activity under stress may be low, permitting telomere loss, or high, partially attenuating it. We developed an experimental model to examine the impacts of extended unpredictable stress on telomerase activity in male rats. Telomerase activity was 54 per cent higher in stressed rats than in controls, and associated with stress-related physiological and behavioural outcomes. This significant increase suggests a potential mechanism for resilience to stress-related ...


An Assessment Of The Effects Of Desertification In Yobe State, Nigeria, Jibril Musa Phd Dec 2012

An Assessment Of The Effects Of Desertification In Yobe State, Nigeria, Jibril Musa Phd

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

Desertification is one of the most serious environmental and socio-economic problems of our time. Desertification describes circumstances of land degradation in arid, semi-arid and dry sub-humid regions resulting from the climatic variation and human activities. The fundamental goal of this thesis was to assess the effects of desertification in Yobe State, Nigeria. The present threat of desertification in the sahel has reached an alarming stage where crops cultivation and animal rearing/grazing are no more productive, soil has lost its nutrient/fertility, various infrastructure had given way because of windstorm from the neighbouring Niger Republic and sand dunes had taken ...


Buried Clay Pipe Irrigation, David A. Bainbridge Dec 2012

Buried Clay Pipe Irrigation, David A. Bainbridge

David A Bainbridge

The buried clay pipe method of irrigation is one of the most efficient systems known and is ideal for gardeners and small farmers. Buried clay pipe irrigation uses a buried, unglazed clay pipe filled with water to provide controlled irrigation to plants as the water seeps out through the clay wall at a rate that is influenced by the plant's water use. It has been used for more than one hundred years.This auto-regulation leads to very high efficiency--considerably better than drip irrigation and many times better than conventional surface irrigation. This also reduces weeds, increases yields, and can ...


Disposition Of Atrazine Metabolites Following Uptake And Degradation Of Atrazine In Switchgrass., Vurtice C. Albright Iii, Joel R. Coats Dec 2012

Disposition Of Atrazine Metabolites Following Uptake And Degradation Of Atrazine In Switchgrass., Vurtice C. Albright Iii, Joel R. Coats

Entomology Publications

Extensive use of the agricultural herbicide atrazine has led to contamination of numerous ground and surface water bodies. Research has shown that it can have a variety of negative impacts on numerous non-target organisms in the environment. Phytoremediation is one strategy that has been studied to remove atrazine contamination. This paper investigates the hypothesis that switchgrass (Panicum virgatum) can exude metabolites of atrazine after uptake and degradation, which has been suggested by prior research. Pots planted with switchgrass were treated with a 4 ppm solution of atrazine spiked with [14C]atrazine. After 4 days, switchgrass plants were transplanted to new ...


Liana Abundance, Diversity, And Distribution On Barro Colorado Island, Panama, Stefan A. Schnitzer, Scott A. Mangan, James W. Dalling, Claire Baldeck, Stephen P. Hubbell, Alicia Ledo, Helene C. Muller-Laudau, Michael F. Tobin, Salomón Aguilar, David Brassfield, Andres Hernandez, Suzanne Lao, Rolando Perez, Oldemar Valdes, Suzanne R. Yorke Dec 2012

Liana Abundance, Diversity, And Distribution On Barro Colorado Island, Panama, Stefan A. Schnitzer, Scott A. Mangan, James W. Dalling, Claire Baldeck, Stephen P. Hubbell, Alicia Ledo, Helene C. Muller-Laudau, Michael F. Tobin, Salomón Aguilar, David Brassfield, Andres Hernandez, Suzanne Lao, Rolando Perez, Oldemar Valdes, Suzanne R. Yorke

Biological Sciences Faculty Research and Publications

Lianas are a key component of tropical forests; however, most surveys are too small to accurately quantify liana community composition, diversity, abundance, and spatial distribution – critical components for measuring the contribution of lianas to forest processes. In 2007, we tagged, mapped, measured the diameter, and identified all lianas ≥1 cm rooted in a 50-ha plot on Barro Colorado Island, Panama (BCI). We calculated liana density, basal area, and species richness for both independently rooted lianas and all rooted liana stems (genets plus clones). We compared spatial aggregation patterns of liana and tree species, and among liana species that varied in ...


An Integrated Genetic Linkage Map For Silkworms With Three Parental Combinations And Its Application To The Mapping Of Single Genes And Qtl, Shuai Zhan, Jianhua Huang, Qiuhong Guo, Yunpo Zhao, Weihua Li, Xuexia Miao, Marian R. Goldsmith, Muwang Li, Yongping Huang Dec 2012

An Integrated Genetic Linkage Map For Silkworms With Three Parental Combinations And Its Application To The Mapping Of Single Genes And Qtl, Shuai Zhan, Jianhua Huang, Qiuhong Guo, Yunpo Zhao, Weihua Li, Xuexia Miao, Marian R. Goldsmith, Muwang Li, Yongping Huang

Marian R Goldsmith

Background: Bombyx mori, the domesticated silkworm, is a well-studied model insect with great economic and scientific significance. Although more than 400 mutations have been described in silkworms, most have not been identified, especially those affecting economically-important traits. Simple sequence repeats (SSRs) are effective and economical tools for mapping traits and genetic improvement. The current SSR linkage map is of low density and contains few polymorphisms. The purpose of this work was to develop a dense and informative linkage map that would assist in the preliminary mapping and dissection of quantitative trait loci (QTL) in a variety of silkworm strains. Results ...


Construction And Sequence Sampling Of Deep-Coverage Large-Insect Bac Libraries For Three Model Lepidopteran Species, Chengcang Wu, Dina Proestou, Dorothy Carter, Erica Nicholson, Filippe Santos, Shaying Zhao, Hong-Bin Zhang, Marian R. Goldsmith Dec 2012

Construction And Sequence Sampling Of Deep-Coverage Large-Insect Bac Libraries For Three Model Lepidopteran Species, Chengcang Wu, Dina Proestou, Dorothy Carter, Erica Nicholson, Filippe Santos, Shaying Zhao, Hong-Bin Zhang, Marian R. Goldsmith

Marian R Goldsmith

Background: Manduca sexta, Heliothis virescens, and Heliconius erato represent three widely-used insect model species for genomic and fundamental studies in Lepidoptera. Large-insert BAC libraries of these insects are critical resources for many molecular studies, including physical mapping and genome sequencing, but not available to date. Results: We report the construction and characterization of six large-insert BAC libraries for the three species and sampling sequence analysis of the genomes. The six BAC libraries were constructed with two restriction enzymes, two libraries for each species, and each has an average clone insert size ranging from 152–175 kb. We estimated that the ...


A Bac-Based Integrated Linkage Map Of The Silkworm Bombyx Mori, Kimiko Yamamoto, Junko Nohata, Keiko Kadono-Okuda, Junko Narukawa, Motoe Sasanuma, Shun-Ichi Sasanuma, Hiroshi Minami, Michihiko Shimomura, Yoshitaka Suetsugu, Yutaka Banno, Kazutoyo Osoegawa, Pieter J. De Jong, Marian R. Goldsmith, Kazuei Mita Dec 2012

A Bac-Based Integrated Linkage Map Of The Silkworm Bombyx Mori, Kimiko Yamamoto, Junko Nohata, Keiko Kadono-Okuda, Junko Narukawa, Motoe Sasanuma, Shun-Ichi Sasanuma, Hiroshi Minami, Michihiko Shimomura, Yoshitaka Suetsugu, Yutaka Banno, Kazutoyo Osoegawa, Pieter J. De Jong, Marian R. Goldsmith, Kazuei Mita

Marian R Goldsmith

Background: In 2004, draft sequences of the model lepidopteran Bombyx mori were reported using whole-genome shotgun sequencing. Because of relatively shallow genome coverage, the silkworm genome remains fragmented, hampering annotation and comparative genome studies. For a more complete genome analysis, we developed extended scaffolds combining physical maps with improved genetic maps. Results: We mapped 1,755 single nucleotide polymorphism (SNP) markers from bacterial artificial chromosome (BAC) end sequences onto 28 linkage groups using a recombining male backcross population, yielding an average inter-SNP distance of 0.81 cM (about 270 kilobases). We constructed 6,221 contigs by fingerprinting clones from three ...