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Polyester-Graft-Phosphorylcholine Prepared By Ring-Opening Polymerization And Click Chemistry, Beth M. Cooper, Delphine Chan-Seng, Debasis Samanta, Xiongfei Zhang, Sangram Parelkar, Todd S. Emrick

Todd S. Emrick

Phosphorylcholine (PC)-substitution on aliphatic polyesters is accomplished by click chemistry with PC-substituted azides.

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Design And Demonstration Of A Small-Animal Up-Conversion Imager, Christopher Salthouse, Scott Hildebrand, Ralph Weissleder, Umar Mahmood

Christopher Salthouse

This first small-animal up-conversion imager (SAUCI) was developed and used for in-vivo imaging of up-converting nanoparticles (UCNs.) Unlike traditional fluorophores, UCNs absorb multiple lower-energy photons and emit a single higher-energy photon. This unique physical process makes it possible to image deeper into tissue with lower background signals. In vivo imaging of particle accumulation in the liver was demonstrated following intravenous injection of particles.

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Centers Of Polymer Science: Introduction, Otto Vogl

Otto Vogl

Centers of Polymer Science describes polymer research activities taking place in Europe, Asia, and Australia primarily during the years between 1980 and 2000. This series of articles shows and records the activity in Polymer Science in this part of polymer history.

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Book I, Otto Vogl: Papers And Patents, 1948-1970, Jane C. Vogl

Otto Vogl

Books I-XII include citations to Otto Vogl's publications and patents. Printed versions of these twelve volumes are also available in the Integrated Sciences and Engineering Library of the University of Massachusetts in Amherst. MA, Lederle Graduate Research Center. The printed volumes include the full reprints of all cited publications.

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Differential Requirements Of Two Reca Mutants For Constitutive Sos Expression In Escherichia Coli K-12, Steven Sandler, Jarukit Edward Long, Nicholas Renzette, Richard Centore

Steven Sandler

Background Repairing DNA damage begins with its detection and is often followed by elicitation of a cellular response. In E. coli, RecA polymerizes on ssDNA produced after DNA damage and induces the SOS Response. The RecA-DNA filament is an allosteric effector of LexA auto-proteolysis. LexA is the repressor of the SOS Response. Not all RecA-DNA filaments, however, lead to an SOS Response. Certain recA mutants express the SOS Response (recAC) in the absence of external DNA damage in log phase cells. Methodology/Principal Findings Genetic analysis of two recAC mutants was used to determine the mechanism of constitutive SOS (SOSC) expression …

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Preschool Parent-Pediatrician Consultations And Predictive Referral Patterns For Problematic Behaviors, John Fanton, Brittany Macdonald, Elizabeth Harvey

Elizabeth (Lisa) Harvey

Objective—The present study examined parents’ reports of the frequency, nature, and outcome of pediatrician consultation and interventions about significant preschool behavior problems. Method—Parents were asked whether they consulted or not with their pediatric providers about disruptive behavioral problems during a longitudinal study of preschool children. Results—Eighty 4-year-old children had parents who had consulted with their pediatricians versus 90 children whose parents did not. Children who eventually met criteria for Attention Deficit/ Hyperactivity Disorder (ADHD) or Oppositional Defiant Disorder (ODD) two years later, received different pediatric interventions at age 4 than children who did not have a diagnosis, χ2 (2) = …

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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 …

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Application Of Two Machine Learning Algorithms To Genetic Association Studies In The Presence Of Covariates, Bareng As Nonyane, Andrea S. Foulkes

Andrea S Foulkes

Background - Population-based investigations aimed at uncovering genotype-trait associations often involve high-dimensional genetic polymorphism data as well as information on multiple environmental and clinical parameters. Machine learning (ML) algorithms offer a straightforward analytic approach for selecting subsets of these inputs that are most predictive of a pre-defined trait. The performance of these algorithms, however, in the presence of covariates is not well characterized. Methods and Results - In this manuscript, we investigate two approaches: Random Forests (RFs) and Multivariate Adaptive Regression Splines (MARS). Through multiple simulation studies, the performance under several underlying models is evaluated. An application to a cohort …

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Surface Wrinkling Behavior Of Finite Circular Plates, Derek Breid, Alfred Crosby

Alfred Crosby

Osmotically-driven surface buckling is a simple method for introducing controlled micro- and nano-scale topography onto material surfaces. To achieve a fundamental understanding of the buckling process and a library of the equilibrium and kinetically-trapped structures that can be attained, we observe the growth processes of a buckling silicate plate rigidly attached to an elastomeric substrate. The primary variable is the lateral extent of the silicate plate which is shown to dictate the location of buckle initiation, and thus the resulting morphology of the final buckled structure. We present a model to qualitatively describe the radial stress profile within the plate, …

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Lexical And Indexical Cues In Masking By Competing Speech, Karen S. Helfer, Richard L. Freyman

Karen S Helfer

Three experiments were conducted using the TVM sentences, a new set of stimuli for competing speech research. These open-set sentences incorporate a cue name that allows the experimenter to direct the listener's attention to a target sentence. The first experiment compared the relative efficacy of directing the listener's attention to the cue name versus instructing the subject to listen for a particular talker's voice. Results demonstrated that listeners could use either cue about equally well to find the target sentence. Experiment 2 was designed to determine whether differences in intelligibility among talkers' voices that were noted when three utterances were …

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Partnerships And The Fiscal Implications Of Planning And Development: A Case Study Of Maynard, Massachusetts, John Mullin, Zenia Kotval, Zeenat Karamchandani

John R. Mullin

Redevelopment of urban sites is an ongoing concern for many communities in the industrial Northeast United States. While many mill sites still languish, examples of successful revitalization can be found. Most of these efforts require more than market conditions to make them viable. Partnerships between developers and the community and state are seen to be crucial. These public-private partnerships come in many forms, not always monetary. The detail and effectiveness of these partnerships often depend on the experience and expertise of developers and community professionals. Given that many of these communities have limited staff, agreements are often made quickly with …

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Book Ii, Otto Vogl: Papers And Patents, 1970-1977, Jane C. Vogl

Otto Vogl

Books I-XII include citations to Otto Vogl's publications and patents. Printed versions of these twelve volumes are also available in the Integrated Sciences and Engineering Library of the University of Massachusetts in Amherst. MA, Lederle Graduate Research Center. The printed volumes include the full reprints of all cited publications.

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Local Chef Inspires Healthy And Economical Cooking -- In A Flash, Madeleine K. Charney

Madeleine K. Charney

Local chef, Leslie Cerier, offers thought-provoking workshops about eating whole foods.

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Pegylated Silicon Nanoparticles: Synthesis And Characterization, P. K. Sudeep, Zachariah Page, Todd S. Emrick

Todd S. Emrick

Silicon nanoparticles were prepared and functionalized with alkene-terminated poly(ethylene oxide) to impart amphiphilic solution properties to the particles.

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Efficient Gene Delivery Vectors By Tuning The Surface Charge Density Of Amino Acid-Functionalized Gold Nanoparticles, Ps Ghosh, Ck Kim, G Han, Ns Forbes, Vm Rotello

Vincent Rotello

Gold colloids functionalized with amino acids provide a scaffold for effective DNA binding with subsequent condensation. Particles with lysine and lysine dendron functionality formed particularly compact complexes and provided highly efficient gene delivery without any observed cytotoxicity. Nanoparticles functionalized with first generation lysine dendrons (NP-LysG1) were approximately 28-fold superior to polylysine in reporter gene expression. These amino acid-based nanoparticles were responsive to intracellular glutathione levels, providing a tool for controlled release and concomitant expression of DNA.

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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 …

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Comparative Genomics Of Geobacter Chemotaxis Genes Reveals Diverse Signaling Function, Hoa T. Tran, Julia Krushkal, Frances M. Antommattei, Derek R. Lovley, Robert Weis

Robert Weis

Background Geobacter species are δ-Proteobacteria and are often the predominant species in a variety of sedimentary environments where Fe(III) reduction is important. Their ability to remediate contaminated environments and produce electricity makes them attractive for further study. Cell motility, biofilm formation, and type IV pili all appear important for the growth of Geobacter in changing environments and for electricity production. Recent studies in other bacteria have demonstrated that signaling pathways homologous to the paradigm established for Escherichia coli chemotaxis can regulate type IV pili-dependent motility, the synthesis of flagella and type IV pili, the production of extracellular matrix material, and …

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Icomos Charter For The Interpretation And Presentation Of Cultural Heritage Sites, Neil A. Silberman

Neil A. Silberman

No abstract provided.

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Spectra Of Nearby Galaxies Measured With A New Very Broadband Receiver, Gopal Narayanan, Ronald L. Snell, Neal A. Erickson, Aeree Chung, Mark H. Heyer, Min Yun, William M. Irvine

Neal Erickson

Three-millimeter-wavelength spectra of a number of nearby galaxies have been obtained at the Five College Radio Astronomy Observatory (FCRAO) using a new, very broadband receiver. This instrument, which we call the Redshift Search Receiver, has an instantaneous bandwidth of 36 GHz and operates from 74 to 110.5 GHz. The receiver has been built at UMass/FCRAO to be part of the initial instrumentation for the Large Millimeter Telescope (LMT) and is intended primarily for determination of the redshift of distant, dust-obscured galaxies. It is being tested on the FCRAO 14 m by measuring the 3 mm spectra of a number of …

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Multiplexed Screening Of Cellular Uptake Of Gold Nanoparticles Using Laser Desorption/Ionization Mass Spectrometry, Zj Zhu, Ps Ghosh, Or Miranda, Rw Vachet, Vm Rotello

Vincent Rotello

Gold nanoparticles (AuNPs) are highly promising candidates as drug delivery agents into cells of interest. We describe for the first time the multiplexed analysis of nanoparticle uptake by cells using mass spectrometry. We demonstrate that the cellular uptake of functionalized gold nanoparticles with cationic or neutral surface ligands can be readily determined using laser desorption/ionization mass spectrometry of cell lysates. The surface ligands have “mass barcodes” that allow different nanoparticles to be simultaneously identified and quantified at levels as low as 30 pmol. Using this method, we find that subtle changes to AuNP surface functionalities can lead to measurable changes …

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Book Iii, Otto Vogl: Publications, 1977-1979, Jane C. Vogl

Otto Vogl

Books I-XII include citations to Otto Vogl's publications and patents. Printed versions of these twelve volumes are also available in the Integrated Sciences and Engineering Library of the University of Massachusetts in Amherst. MA, Lederle Graduate Research Center. The printed volumes include the full reprints of all cited publications.

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Exploitative Competition Between Invasive Herbivores Benefits A Native Host Plant, Joseph Elkinton, E. L. Preisser

Joseph Elkinton

Although biological invasions are of considerable concern to ecologists, relatively little attention has been paid to the potential for and consequences of indirect interactions between invasive species. Such interactions are generally thought to enhance invasives' spread and impact (i.e., the “invasional meltdown” hypothesis); however, exotic species might also act indirectly to slow the spread or blunt the impact of other invasives. On the east coast of the United States, the invasive hemlock woolly adelgid (Adelges tsugae, HWA) and elongate hemlock scale (Fiorinia externa, EHS) both feed on eastern hemlock (Tsuga canadensis). Of the two insects, HWA is considered far more …

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Graphite Electrode As A Sole Electron Donor For Reductive Dechlorination Of Tetrachlorethene By Geobacter Lovleyi, Derek Lovley, Sarah M. Strycharz, Trevor L. Woodard, Jessica P. Johnson, Kelly P. Nevin, Robert A. Stanford, Frank E. Lӧffler

Derek Lovley

The possibility that graphite electrodes can serve as the direct electron donor for microbially catalyzed reductive dechlorination was investigated with Geobacter lovleyi. In an initial evaluation of whether G. lovleyi could interact electronically with graphite electrodes, cells were provided with acetate as the electron donor and an electrode as the sole electron acceptor. Current was produced at levels that were ca. 10-fold lower than those previously reported for Geobacter sulfurreducens under similar conditions, and G. lovleyi anode biofilms were correspondingly thinner. When an electrode poised at −300 mV (versus a standard hydrogen electrode) was provided as the electron donor, G. …

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Mass Producing The Personal: The Greeting Card Industry’S Approach To Commercial Sentiment, Emily West

Emily E. West

The greeting card industry manages the challenge of mass-producing images and texts for use in interpersonal communication through both specific production techniques and narratives that “make sense” of this seemingly paradoxical task. The mass production of the personal is negotiated in the processes of writing sentiments and creating designs, as well as in identifying sending situations for cards. At Hallmark, the approach to creating emotional, relational communication for anonymous others is captured by the phrase “universal specificity,” which suggests that people’s emotions are essentially universal, and that the industry can meet the nation’s social expression needs by customizing these core …

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Potential Of Using Breast Milk As A Tool To Study Breast Cancer And Breast Cancer Risk, Kathleen Arcaro, Douglas L. Anderton

Douglas L. Anderton

No abstract provided.

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Wildfires, Communities, And Agencies: Stakeholders’ Perceptions Of Postfire Forest Restoration And Rehabilitation, Elisabeth M. Hamin, Robert L. Ryan

Elisabeth M. Hamin

After wildfire, land managers are often called on to undertake complex restoration activities while also managing relations with wildfire-devastated communities. This research investigates the community–US Forest Service agency relations in the postwildfire period in three western US communities. In each community, we interviewed key informant representatives from government, business, environmental organizations, and recreation groups and conducted focus groups to gather input from residents located near burn areas. The goal was to understand how forest restoration and rehabilitation efforts and agency outreach were perceived by stakeholders who were recently affected by wildfire and how these perceptions were related to underlying community …

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Book Iv, Otto Vogl: Publications, 1979-1981, Jane C. Vogl

Otto Vogl

Books I-XII include citations to Otto Vogl's publications and patents. Printed versions of these twelve volumes are also available in the Integrated Sciences and Engineering Library of the University of Massachusetts in Amherst. MA, Lederle Graduate Research Center. The printed volumes include the full reprints of all cited publications.

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The Role Of Gtp Binding And Hydrolysis At The Attoc159 Preprotein Receptor During Protein Import Into Chloroplasts, Danny Schnell, F. Wang, B. Agne, F. Kessler

Danny Schnell

The majority of nucleus-encoded chloroplast proteins are targeted to the organelle by direct binding to two membrane-bound GTPase receptors, Toc34 and Toc159. The GTPase activities of the receptors are implicated in two key import activities, preprotein binding and driving membrane translocation, but their precise functions have not been defined. We use a combination of in vivo and in vitro approaches to study the role of the Toc159 receptor in the import reaction. We show that atToc159-A864R, a receptor with reduced GTPase activity, can fully complement a lethal insertion mutation in the ATTOC159 gene. Surprisingly, the atToc159-A864R receptor increases the rate …

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Highly Conserved Genes In Geobacter Species With Expression Patterns Indicative Of Acetate Limitation, Derek Lovley, Carla Risso, Barbara A. Methé, Hila Elifantz, Dawn E. Holmes

Derek Lovley

Analysis of the genome of Geobacter sulfurreducens revealed four genes encoding putative symporters with homology to ActP, an acetate transporter in Escherichia coli. Three of these genes, aplA, aplB and aplC, are highly similar (over 90 % identical) and fell within a tight phylogenetic cluster (Group I) consisting entirely of Geobacter homologues. Transcript levels for all three genes increased in response to acetate limitation. The fourth gene, aplD, is phylogenetically distinct (Group II) and its expression was not influenced by acetate availability. Deletion of any one of the three genes in Group I did not significantly affect acetate-dependent growth, suggesting …

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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 …

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Full-Text Articles in Entire DC Network

Polyester-Graft-Phosphorylcholine Prepared By Ring-Opening Polymerization And Click Chemistry, Beth M. Cooper, Delphine Chan-Seng, Debasis Samanta, Xiongfei Zhang, Sangram Parelkar, Todd S. Emrick

Todd S. Emrick

Design And Demonstration Of A Small-Animal Up-Conversion Imager, Christopher Salthouse, Scott Hildebrand, Ralph Weissleder, Umar Mahmood

Christopher Salthouse

Centers Of Polymer Science: Introduction, Otto Vogl

Otto Vogl

Book I, Otto Vogl: Papers And Patents, 1948-1970, Jane C. Vogl

Otto Vogl

Differential Requirements Of Two Reca Mutants For Constitutive Sos Expression In Escherichia Coli K-12, Steven Sandler, Jarukit Edward Long, Nicholas Renzette, Richard Centore

Steven Sandler

Preschool Parent-Pediatrician Consultations And Predictive Referral Patterns For Problematic Behaviors, John Fanton, Brittany Macdonald, Elizabeth Harvey

Elizabeth (Lisa) Harvey

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

Application Of Two Machine Learning Algorithms To Genetic Association Studies In The Presence Of Covariates, Bareng As Nonyane, Andrea S. Foulkes

Andrea S Foulkes

Surface Wrinkling Behavior Of Finite Circular Plates, Derek Breid, Alfred Crosby

Alfred Crosby

Lexical And Indexical Cues In Masking By Competing Speech, Karen S. Helfer, Richard L. Freyman

Karen S Helfer

Partnerships And The Fiscal Implications Of Planning And Development: A Case Study Of Maynard, Massachusetts, John Mullin, Zenia Kotval, Zeenat Karamchandani

John R. Mullin

Book Ii, Otto Vogl: Papers And Patents, 1970-1977, Jane C. Vogl

Otto Vogl

Local Chef Inspires Healthy And Economical Cooking -- In A Flash, Madeleine K. Charney

Madeleine K. Charney

Pegylated Silicon Nanoparticles: Synthesis And Characterization, P. K. Sudeep, Zachariah Page, Todd S. Emrick

Todd S. Emrick

Efficient Gene Delivery Vectors By Tuning The Surface Charge Density Of Amino Acid-Functionalized Gold Nanoparticles, Ps Ghosh, Ck Kim, G Han, Ns Forbes, Vm Rotello

Vincent Rotello

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

Tobias Baskin

Comparative Genomics Of Geobacter Chemotaxis Genes Reveals Diverse Signaling Function, Hoa T. Tran, Julia Krushkal, Frances M. Antommattei, Derek R. Lovley, Robert Weis

Robert Weis

Icomos Charter For The Interpretation And Presentation Of Cultural Heritage Sites, Neil A. Silberman

Neil A. Silberman

Spectra Of Nearby Galaxies Measured With A New Very Broadband Receiver, Gopal Narayanan, Ronald L. Snell, Neal A. Erickson, Aeree Chung, Mark H. Heyer, Min Yun, William M. Irvine

Neal Erickson

Multiplexed Screening Of Cellular Uptake Of Gold Nanoparticles Using Laser Desorption/Ionization Mass Spectrometry, Zj Zhu, Ps Ghosh, Or Miranda, Rw Vachet, Vm Rotello

Vincent Rotello

Book Iii, Otto Vogl: Publications, 1977-1979, Jane C. Vogl

Otto Vogl

Exploitative Competition Between Invasive Herbivores Benefits A Native Host Plant, Joseph Elkinton, E. L. Preisser

Joseph Elkinton

Graphite Electrode As A Sole Electron Donor For Reductive Dechlorination Of Tetrachlorethene By Geobacter Lovleyi, Derek Lovley, Sarah M. Strycharz, Trevor L. Woodard, Jessica P. Johnson, Kelly P. Nevin, Robert A. Stanford, Frank E. Lӧffler

Derek Lovley

Mass Producing The Personal: The Greeting Card Industry’S Approach To Commercial Sentiment, Emily West

Emily E. West

Potential Of Using Breast Milk As A Tool To Study Breast Cancer And Breast Cancer Risk, Kathleen Arcaro, Douglas L. Anderton

Douglas L. Anderton

Wildfires, Communities, And Agencies: Stakeholders’ Perceptions Of Postfire Forest Restoration And Rehabilitation, Elisabeth M. Hamin, Robert L. Ryan

Elisabeth M. Hamin

Book Iv, Otto Vogl: Publications, 1979-1981, Jane C. Vogl

Otto Vogl

The Role Of Gtp Binding And Hydrolysis At The Attoc159 Preprotein Receptor During Protein Import Into Chloroplasts, Danny Schnell, F. Wang, B. Agne, F. Kessler

Danny Schnell

Highly Conserved Genes In Geobacter Species With Expression Patterns Indicative Of Acetate Limitation, Derek Lovley, Carla Risso, Barbara A. Methé, Hila Elifantz, Dawn E. Holmes

Derek Lovley

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