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Articles 1 - 30 of 43
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Extension Workers As Orchestrators Of Civic Renewal Through Civic Professionalism, Nancy K. Franz
Extension Workers As Orchestrators Of Civic Renewal Through Civic Professionalism, Nancy K. Franz
Nancy K. Franz
I have a passion and a bias. I am passionate about the important role of the Cooperative Extension System (CES) in civic renewal. My bias is that extension workers (also known as agents or educators) are the key to civic renewal throughout the United States. No other institution has the same ability to reach all of America with education and organizing efforts. With extension workers in every county in the nation, this group of professionals and their work cut across age, race, ethnicity, religion, geography and many other demographic characteristics. Extension has a long history of being active in civic …
Temperature-Induced Configurational Excitations For Predicting Thermodynamic And Mechanical Properties Of Alloys, Duane D. Johnson, Andrei V. Smirnov, J. B. Staunton, F. J. Pinski, W. A. Shelton
Temperature-Induced Configurational Excitations For Predicting Thermodynamic And Mechanical Properties Of Alloys, Duane D. Johnson, Andrei V. Smirnov, J. B. Staunton, F. J. Pinski, W. A. Shelton
Duane D. Johnson
We show that a structural energy difference, ΔE, must include explicit symmetry-breaking changes of the electronic structure due to temperature-induced configurational excitations, and why ΔE at T=0 K is not necessarily relevant to thermodynamic and mechanical modeling. In Ni3V, we calculate a tenfold decrease of ΔE between D022 and L12 structures from T=0 K to states of order relevant to experiment. ΔE calculated directly from states with short-range order (8 meV) or with low partial order (7–12 meV) agree with high-T experiment (10 meV).
Tackling The Iso 14000 Maze: Which Firms Adopt And Which Do Not?, Steven A. Melnyk, Robert Sroufe, Frank L. Montabon, Roger Calantone
Tackling The Iso 14000 Maze: Which Firms Adopt And Which Do Not?, Steven A. Melnyk, Robert Sroufe, Frank L. Montabon, Roger Calantone
Frank L. Montabon
ISO 14000 constitutes a major dilemma for most American firms in that they are not sure whether or not to actively pursue this new form of certification. This new standard is attractive as it holds the promise of helping firms become more efficient via better management of waste, yet this new standard deals with environmental performance, a potentially dangerous legal area. Both benefits and cost liabilities are very difficult to quantify and forecast. This leads to great uncertainty as to whether the benefits offered by improving environmental performance are sufficient to outweigh the costs incurred in obtaining certification. This study …
Environmentally Responsible Manufacturing: Assessing The Current State In American Industry, Steven A. Melnyk, Robert Sroufe, Frank L. Montabon, Roger Calantone
Environmentally Responsible Manufacturing: Assessing The Current State In American Industry, Steven A. Melnyk, Robert Sroufe, Frank L. Montabon, Roger Calantone
Frank L. Montabon
To some managers Environmentally Responsible Manufacturing (ERM) can be seen as an opportunity to better understand processes and reduce waste. To others, ERM is an unwarranted intrusion into their functional responsibilities. This paper explores the reasons for these two very different views of ERM. The paper begins by defining the concepts of ERM and Environmental Management Systems (EMS) and identifying the reasons for the increasing importance now associated with each of these concepts. Drawing on the results of a large-scale survey of American managers, a summary of current practices associated with EMS at the plant level is given. Additionally, analysis …
Statistical Representation Of A Spray As A Point Process, Shankar Subramaniam
Statistical Representation Of A Spray As A Point Process, Shankar Subramaniam
Shankar Subramaniam
The statistical representation of a spray as a finite point process is investigated. One objective is to develop a better understanding of how single-point statistical information contained in descriptions such as the droplet distribution function ~ddf!, relates to the probability density functions ~pdfs! associated with the droplets themselves. Single-point statistical information contained in the droplet distribution function ~ddf! is shown to be related to a sequence of single surrogate-droplet pdfs, which are in general different from the physical single-droplet pdfs. It is shown that the ddf contains less information than the fundamental single-point statistical representation of the spray, which is …
Yponomeuta Evonymellus Outbreaks In Southern Finland: Spatial Synchrony But Different Local Magnitudes, Brian J. Wilsey, Conchita Alonso, Timo Vuorisalo, Tuija Honkanen
Yponomeuta Evonymellus Outbreaks In Southern Finland: Spatial Synchrony But Different Local Magnitudes, Brian J. Wilsey, Conchita Alonso, Timo Vuorisalo, Tuija Honkanen
Brian J. Wilsey
Defoliations of Prunus padus by Yponomeuta evonymellus were monitored in two areas in southern Finland. During a long-term study (1980–1995) in the area with high peak defoliations, P. padus trees recorded two defoliation peaks, leading to complete defoliation of many trees. The negative relationship between pupal mass and current year tree defoliation during the peak years suggested shortage of food affected reproductive potential of Y. evonymellus. Furthermore, no delayed induced resistance was observed in these populations. Interannual correlations in degrees of defoliation experienced by individual trees were low, i.e. high defoliation in one year did not predict the degree of …
Damper For Brake Noise Reduction (Brake Drums), Jonathan A. Wickert, Adnan Akay
Damper For Brake Noise Reduction (Brake Drums), Jonathan A. Wickert, Adnan Akay
Jonathan A. Wickert
An apparatus of reducing unwanted brake noise has a ring damper affixed around a periphery of brake drum in a drum brake system in a manner that permits relative motion and slippage between the ring damper and the brake drum when the brake drum vibrates during braking. In a preferred embodiment, the ring damper is an almost circular ring that is inserted in a groove formed in the periphery of the brake drum. The ring damper is held in place by the groove itself and by the interference pre-load or pre-tension between the ring damper and the brake drum.
Avhrr Estimates Of Surface Temperature During The Southern Great Plains 1997 Experiment, Amy L. Kaleita, Praveen Kumar
Avhrr Estimates Of Surface Temperature During The Southern Great Plains 1997 Experiment, Amy L. Kaleita, Praveen Kumar
Amy L. Kaleita
In this study we aim to (1) explore the differences in the accuracy of satellitederived land-surface skin temperature for day and nighttime observations, (2) assess the effects of large solar zenith angles, and (3) develop an understanding of the spatial variability of the observed temperatures. Land-surface skin temperatures are obtained using the split-window technique from observations of the AVHRR instrument aboard the NOAA-12 and NOAA-14 satellites for the SGP97 (Southern Great Plains 1997) hydrology experiment. From the study of several days of observations we find that observed biases with respect to the ground temperature, both during day and night, are …
North Carolina State University Summer Transition Program – A High School To College Bridge Program For Enhancing Undergraduate Engineering Education, Tony L. Mitchell, Alisa Hunt-Lowery, Sarah A. Rajala
North Carolina State University Summer Transition Program – A High School To College Bridge Program For Enhancing Undergraduate Engineering Education, Tony L. Mitchell, Alisa Hunt-Lowery, Sarah A. Rajala
Sarah A. Rajala
The NC State University College of Engineering is an internationally recognized producer of engineers and computer scientists who are prepared to make an immediate contribution to the workforce. Our research faculty are recognized around the world for cutting edge research. Essential to our mission and continued success is a steady stream of top-notch students who contribute to and celebrate ethnic, academic and gender diversity. Each year an entering freshman class of 1100 new engineering students includes 20% women and 20% underrepresented minority students. The rate at which they persist through our undergraduate program is impacted by how they adapt during …
North Carolina State University Center For Minority Engineer Development, Tony L. Mitchell, Sarah A. Rajala, Laura J. Bottomley, Mary Clare Robbins
North Carolina State University Center For Minority Engineer Development, Tony L. Mitchell, Sarah A. Rajala, Laura J. Bottomley, Mary Clare Robbins
Sarah A. Rajala
North Carolina State University, located in Raleigh, North Carolina, USA, is the largest state-supported university of the sixteen-campus University of North Carolina educational system. The College of Engineering at NC State University is among the best in the country, offering outstanding degree programs and preparing students for exciting and rewarding careers. Our graduates are heavily recruited internationally for positions in a variety of settings, including business management, construction, transportation, hardware and software development, computer engineering and design. The College of Engineering comprises 10 departments offering 16 BS, 17 MS, and 14 Ph.D. degree programs and conducts the largest undergraduate and …
Developing Construction Claims For Arbitration: Two Arbitrators' Viewpoint, Douglas D. Gransberg, Charles A. Joplin
Developing Construction Claims For Arbitration: Two Arbitrators' Viewpoint, Douglas D. Gransberg, Charles A. Joplin
Douglas D. Gransberg
Two arbitrators' viewpoints of construction claims development are provided in the hope that the information will be useful to those needing to resolve construction claims by arbitration. It also may help to reduce the volume of costly and unnecessary documentation. Because of arbitration's relative formality, attorneys representing construction contractors and owners tend to prepare their cases in the same way as they would for litigation. This leads to potential information overkill, which threatens the arbitration panel's ability to easily sort through and understand the issues in its quest for a fair and equitable decision.
Spin Fluctuations In Nearly Magnetic Metals From Ab Initio Dynamical Spin Susceptibility Calculations: Application To Pd And Cr95v5, J. B. Staunton, J. Poulter, B. Ginatempo, E. Bruno, Duane D. Johnson
Spin Fluctuations In Nearly Magnetic Metals From Ab Initio Dynamical Spin Susceptibility Calculations: Application To Pd And Cr95v5, J. B. Staunton, J. Poulter, B. Ginatempo, E. Bruno, Duane D. Johnson
Duane D. Johnson
We describe our theoretical formalism and computational scheme for making ab initio calculations of the dynamic paramagnetic spin susceptibilities of metals and alloys at finite temperatures. Its basis is time-dependent density functional theory within an electronic multiple scattering, imaginary time Green function formalism. Results receive a natural interpretation in terms of overdamped oscillator systems making them suitable for incorporation into spin fluctuation theories. For illustration we apply our method to the nearly ferromagnetic metal Pd and the nearly antiferromagnetic chromium alloy Cr95V5. We compare and contrast the spin dynamics of these two metals and in each case identify those fluctuations …
Scaling And Parameterization Of Stratified Homogeneous Turbulent Shear Flow, Lucinda H. Shih, Jeffrey R. Koseff, Joel H. Ferziger, Chris R. Rehmann
Scaling And Parameterization Of Stratified Homogeneous Turbulent Shear Flow, Lucinda H. Shih, Jeffrey R. Koseff, Joel H. Ferziger, Chris R. Rehmann
Chris R. Rehmann
Homogeneous sheared stratified turbulence was simulated using a DNS code. The initial turbulent Reynolds numbers (Re) were 22, 44, and 89, and the initial dimensionless shear rate (S*) varied from 2 to 16. We found (similarly to Rogers (1986) for unstratified flows) the final value of S* at high Re to be [similar] 11, independent of initial S*. The final S* varies at low Re, in agreement with Jacobitz et al. (1997). At low Re, the stationary Richardson number (Ris) depends on both Re and S*, but at higher Re, it varies only with Re. A scaling based on the …
Diapycnal Diffusivity Inferred From Scalar Microstructure Measurements Near The New England Shelf/Slope Front, Chris R. Rehmann, Timothy F. Duda
Diapycnal Diffusivity Inferred From Scalar Microstructure Measurements Near The New England Shelf/Slope Front, Chris R. Rehmann, Timothy F. Duda
Chris R. Rehmann
Conductivity microstructure was used to estimate the diapycnal thermal eddy diffusivity KT near the New England shelf/slope front in early August 1997. Two datasets were collected with a towed vehicle. One involved several horizontal tows in and above a warm, salty layer near the seafloor, and the other was from a tow-yo transect that sampled most of the water column. In the bottom layer, KT derived from microstructure is a factor of about 5 smaller than estimates derived from tracer dispersion at the same density level, and the diffusivity decreases sharply as the buoyancy frequency N increases: KT N−3.1. With …
Conjectural Estimates Of Economic Growth In The Lower South, 1720 To 1800, Peter C. Mancall, Joshua L. Rosenbloom, Thomas Weiss
Conjectural Estimates Of Economic Growth In The Lower South, 1720 To 1800, Peter C. Mancall, Joshua L. Rosenbloom, Thomas Weiss
Joshua L. Rosenbloom
This paper describes the first step in a larger project to build up regional estimates of economic growth before 1800 in the parts of North America that became the United States. In it we employ the method of conjectural estimation to develop new estimates of the rate of economic growth in the Lower South (modern day North Carolina, South Carolina, Georgia, and Tennessee) from 1720 to 1800 for both colonists and the Native American population of the region. Contrary to the widely held view that GDP per capita grew at a rate of 0.3 to 0.6 percent per year during …
Viability Of Competing Field Theories For The Driven Lattice Gas, Beate Schmittmann, H. K. Janssen, U. C. Tauber, R. K. P. Zia, K.-T. Leung, J. L. Cardy
Viability Of Competing Field Theories For The Driven Lattice Gas, Beate Schmittmann, H. K. Janssen, U. C. Tauber, R. K. P. Zia, K.-T. Leung, J. L. Cardy
Beate Schmittmann
It has recently been suggested that the driven lattice gas should be described by an alternate field theory in the limit of infinite drive. We review the original and the alternate field theory, invoking several well-documented key features of the microscopics. Since the alternate field theory fails to reproduce these characteristics, we argue that it cannot serve as a viable description of the driven lattice gas. Recent results, for the critical exponents associated with this theory, are reanalyzed and shown to be incorrect.
An Experimental Study Of Molten Microdroplet Surface Deposition And Solidification: Transient Behavior And Wetting Angle Dynamics, Daniel Attinger, Z. Zhao, D. Poulikakos
An Experimental Study Of Molten Microdroplet Surface Deposition And Solidification: Transient Behavior And Wetting Angle Dynamics, Daniel Attinger, Z. Zhao, D. Poulikakos
Daniel Attinger
The basic problem of the impact and solidification of molten droplets on a substrate is of central importance to a host of processes. An important and novel such process in the area of micromanufacturing is solder jetting where microscopic solder droplets are dispensed for the attachment of microelectronic components. Despite the recent appearance of a few numerical studies focusing on the complex transient aspects of this process, no analogous experimental results have been reported to date to the best of our knowledge. Such a study is reported in this paper. Eutectic solder (63Sn37Pb) was melted to a preset superheat and …
Cloning And Sequencing Of The Iss Gene From A Virulent Avian Escherichia Coli, Shelley M. Horne, Samantha J. Pfaff-Mcdonough, Catherine W. Giddings, Lisa K. Nolan
Cloning And Sequencing Of The Iss Gene From A Virulent Avian Escherichia Coli, Shelley M. Horne, Samantha J. Pfaff-Mcdonough, Catherine W. Giddings, Lisa K. Nolan
Lisa K. Nolan
Control of colibacillosis is important to the poultry industry. We have found that the presence of a gene for increased serum survival, iss, is strongly correlated with Escherichia coli isolated from birds with colibacillosis. Therefore, the iss gene and its protein product, Iss, are potential targets for detection and control of avian colibacillosis. The iss gene was amplified from a virulent avian E. coli isolate and sequenced. The sequences of the gene and the predicted protein product were compared with those of iss from a human E. coli isolate and lambda bor. The iss gene from the avian E. coli …
Countrysides Transformed, Pamela Riney-Kehrberg
Countrysides Transformed, Pamela Riney-Kehrberg
Pamela Riney-Kehrberg
Rural and agricultural history provide their readers different perspectives on the ways in which the countryside has changed over the course of American history. Rural history approaches the question of change from the perspective of communities and families, while agricultural history generally eschews the social perspective for issues of crop production. Such is the case of two recent and important books in rural and agricultural history, Hal Barron's Mixed Harvest: The Second Great Transformationin the Rural North, 1870-1930 and Steven Stoll's The Fruits of Natural Advantage: The Making of the Industrial Countryside in California. While both authors are intimately concerned …
Iss From A Virulent Avian Escherichia Coli, Steven L. Foley, Shelley M. Horne, Catherine W. Giddings, Michael Robinson, Lisa K. Nolan
Iss From A Virulent Avian Escherichia Coli, Steven L. Foley, Shelley M. Horne, Catherine W. Giddings, Michael Robinson, Lisa K. Nolan
Lisa K. Nolan
No single characteristic of virulent avian Escherichia coli has been identified that can be exploited in colibacillosis detection protocols. Research in our lab suggests a strong association between the presence of an iss DNA sequence with an isolate's disease-causing ability. The study presented here focuses on the techniques used in the expression, purification, and characterization of avian E. coli Iss protein. In brief, iss was cloned into an expression vector, the construct was transformed into a protease-deficient E. coli, and expression was induced. The protein was expressed as a glutathione-S-transferase (GST) fusion and purified by affinity chromatography. The GST portion …
Complement Resistance-Related Traits Among Escherichia Coli Isolates From Apparently Healthy Birds And Birds With Colibacillosis, Samantha J. Pfaff-Mcdonough, Shelley M. Horne, Catherine W. Giddings, Jessica O. Ebert, Curt Doetkott, M. Herbert Smith, Lisa K. Nolan
Complement Resistance-Related Traits Among Escherichia Coli Isolates From Apparently Healthy Birds And Birds With Colibacillosis, Samantha J. Pfaff-Mcdonough, Shelley M. Horne, Catherine W. Giddings, Jessica O. Ebert, Curt Doetkott, M. Herbert Smith, Lisa K. Nolan
Lisa K. Nolan
In this study, 294 Escherichia coli isolates from birds with colibacillosis were collected from disease outbreaks throughout the United States and were compared with 75 fecal E. coli isolates of apparently healthy chickens by their possession of several purported virulence genes, resistance to rough-lipopolysaccharide-specific bacteriophages (rLPSr), and elaboration of capsule. Traits were selected for study on the basis of their association with complement resistance. The genes targeted in this study included those encoding colicin V (cvaC) and the outer membrane proteins TraT (traT), OmpA (ompA), and Iss (iss). No significant differences were found between the two groups of isolates in …
Roadways And The Land: The Landscape Architect's Role, Elizabeth E. Fischer, Heidi M. Hohmann, P. Daniel Marriott
Roadways And The Land: The Landscape Architect's Role, Elizabeth E. Fischer, Heidi M. Hohmann, P. Daniel Marriott
Heidi Hohmann
This country has a rich history of roadway development. From early overland routes, such as the Boston Post Road in New England and the El Camino Reals in the Southwest, to the first federally funded interstate in 1806 (the National Road) and the innovative parkways of the early 20th century, we have been striving in creative ways to link our people, resources, and communities.
Universal Aspects Of Vacancy-Mediated Disordering Dynamics: The Effect Of External Fields, Wannapong Triampo, Timo Aspelmeier, Beate Schmittmann
Universal Aspects Of Vacancy-Mediated Disordering Dynamics: The Effect Of External Fields, Wannapong Triampo, Timo Aspelmeier, Beate Schmittmann
Beate Schmittmann
We investigate the disordering of an initially phase-segregated binary alloy, due to a highly mobile defect which couples to an electric or gravitational field. Using both mean-field and Monte Carlo methods, we show that the late stages of this process exhibit dynamic scaling, characterized by a set of exponents and scaling functions. A new scaling variable emerges, associated with the field. While the scaling functions carry information about the field and the boundary conditions, the exponents are universal. They can be computed analytically, in excellent agreement with simulation results.
A Buried Spruce Forest Provides Evidence At The Stand And Landscape Scale For The Effects Of Environment On Vegetation At The Pleistocene/Holocene Boundary, Douglas D. Stokke
A Buried Spruce Forest Provides Evidence At The Stand And Landscape Scale For The Effects Of Environment On Vegetation At The Pleistocene/Holocene Boundary, Douglas D. Stokke
Douglas D. Stokke
Due to a unique set of circumstances, we were able to excavate an entire spruce (Picea) forest in Michigan's Upper Peninsula, USA, which was buried in the early Holocene (9928 ± 133 uncalibrated 14C years bp). Trees ranged from < 5 cm to > 50 cm in diameter, and dominants were approximately 9 m tall. The stand was multi-aged, with a maximum tree age of 145 years. Well-preserved stem cross-sections (n = 140) were recovered and the entire stand was mapped. Stand reconstruction combined with pollen and sediment analysis revealed a pure spruce forest in the sandy lowlands surrounded by hills dominated by pine, oak …
Endocrine Responses To Chronic Androstenedione Intake In 30- To 56-Year-Old Men, Gregory A. Brown, Matthew D. Vukovich, Emily R. Martini, Marian L. Kohut, Warren D. Franke, David A. Jackson, Douglas S. King
Endocrine Responses To Chronic Androstenedione Intake In 30- To 56-Year-Old Men, Gregory A. Brown, Matthew D. Vukovich, Emily R. Martini, Marian L. Kohut, Warren D. Franke, David A. Jackson, Douglas S. King
Warren D Franke
In young men, chronic ingestion of 100 mg androstenedione (ASD), three times per day, does not increase serum total testosterone but does increase serum estrogen and ASD concentrations. We investigated the effects of ASD ingestion in healthy 30- to 56-yr-old men. In a double-blind, randomly assigned manner, subjects consumed 100 mg ASD three times daily (n 5 28), or placebo (n 5 27) for 28 days. Serum ASD , dihydrotestosterone (DHT), free and total testosterone, estradiol, prostate-specific antigen (PSA), and lipid concentrations were measured at week 0 and each week throughout the supplementation period. Serum total testosterone and PSA concentrations …
High-Pressure Effects On Lysosome Integrity And Lysosomal Enzyme Activity In Bovine Muscle, Stéphanie Jung, Marie De Lamballerie-Anton, Richard G. Taylor, Mohamed Ghoul
High-Pressure Effects On Lysosome Integrity And Lysosomal Enzyme Activity In Bovine Muscle, Stéphanie Jung, Marie De Lamballerie-Anton, Richard G. Taylor, Mohamed Ghoul
Stéphanie Jung
This study was conducted to determine whether the application of high hydrostatic pressure could modify the enzymatic activity and membrane integrity of lysosomes in muscle. Several combinations of pressure (0-600 MPa) and time (0-300 s) were applied to two types of samples: purified enzymes (cathepsin D and acid phosphatase) in buffer solution and intact muscle (biceps femoris). The enzymes studied showed varying degrees of susceptibility depending on the level of pressure, holding time, and environment. Acid phosphatase activity was minimally affected by pressure in buffer solution, whereas cathepsin D was modulated significantly by the pressure and time applied. The activities …
Topography-Induced Contributions To Friction Forces Measured Using An Atomic Force/Friction Force Microscope, Sriram Sundararajan, Bharat Bhushan
Topography-Induced Contributions To Friction Forces Measured Using An Atomic Force/Friction Force Microscope, Sriram Sundararajan, Bharat Bhushan
Sriram Sundararajan
Most friction studies using an atomic force/friction force microscope, while concentrating on material-induced effects, often present users with conflicting and confusing interpretations of the topography-induced friction forces. It has been generally reported that topography-induced contributions are independent of scanning direction and can be removed by subtracting friction data from forward and backward scans. In this article, we present friction studies on samples with well-defined topography variations and find that the above-given statement is not generally true. At surface locations involving significant changes in topography, the topography-induced contributions to friction forces are found to be different between forward and backward scanning …
Spatial Modulation Of Repeated Vibration Modes In Rotationally Periodic Structures, M. Kim, J. Moon, Jonathan A. Wickert
Spatial Modulation Of Repeated Vibration Modes In Rotationally Periodic Structures, M. Kim, J. Moon, Jonathan A. Wickert
Jonathan A. Wickert
When a structure deviates from axisymmetry because of circumferentially varying model features, significant changes can occur to its natural frequencies and modes, particularly for the doublet modes that have non-zero nodal diameters and repeated natural frequencies in the limit of axisymmetry. Of technical interest are configurations in which inertia, dissipation, stiffness, or domain features are evenly distributed around the structure. Aside from the well-studied phenomenon of eigenvalue splitting, whereby the natural frequencies of certain doublets split into distinct values, modes of the axisymmetric structure that are precisely harmonic become contaminated with certain additional wavenumbers. From analytical, numerical, and experimental perspectives, …
Biodiversity And Ecosystem Functioning: Importance Of Species Evenness In An Old Field, Brian J. Wilsey, Catherine Potvin
Biodiversity And Ecosystem Functioning: Importance Of Species Evenness In An Old Field, Brian J. Wilsey, Catherine Potvin
Brian J. Wilsey
Changes in land use, habitat fragmentation, nutrient enrichment, and environmental stress often lead to reduced plant diversity in ecosystems. However, it remains controversial whether these reductions in diversity will affect energy flow and nutrient cycling. Diversity has two components: species richness, or the number of plant species in a given area, and species evenness, or how well distributed abundance or biomass is among species within a community. We experimentally varied species evenness and the identity of the dominant plant species in an old field of Quebec to test whether plant productivity would increase with increasing levels of evenness, and whether …
Effects Of Resource Availability On Carbon Allocation And Developmental Instability In Cloned Birch Seedlings, Brian J. Wilsey, Janne H. Lappalainen, Jocelyn Martel, Kyösti Lempa, Vladimir Ossipov
Effects Of Resource Availability On Carbon Allocation And Developmental Instability In Cloned Birch Seedlings, Brian J. Wilsey, Janne H. Lappalainen, Jocelyn Martel, Kyösti Lempa, Vladimir Ossipov
Brian J. Wilsey
Abundant nitrogen improves seedling growth and establishment. Vigorous growth brings about changes in rates and patterns of plant development and changes in the relationship between primary and secondary metabolism, which may make seedlings more susceptible to herbivores and pathogens than are slow-growing seedlings. We studied how nitrogen fertilization and manual defoliation of source leaves affect growth, carbon allocation, and developmental instability in cloned seedlings of white birch (Betula pubescens Ehrh.). Biomass was higher, whereas concentrations of most classes of phenolic compounds were lower in the nitrogen-rich environment. Interestingly, fertilization did not change the concentrations of cell wall–bound proanthocyanidins, which represent …