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Compiling, Synthesizing And Analyzing Existing Boreal Forest Fire History Data In Alaska, Diana L. Olson, James B. Cronan, Donald Mckenzie, Jennifer L. Barnes, Anne E. Camp, Mike Tjoelker, Jennifer Northway, Paige Eagle

Joint Fire Science Program Research Project Reports

Wildland fires play a critical role in maintaining the ecological integrity of boreal forests in Alaska. Identifying and maintaining natural fire regimes is an important component of fire management. There are numerous research projects that directly or indirectly address historical fire regimes in the Alaskan boreal forest, but many are unpublished, have many unprocessed dendrochronological (tree age and fire scar) samples, or their data were used for other purposes. Furthermore, no assessment of these data exists to understand how fire has historically affected the boreal forest ecosystems of Alaska. The goal of this project was to compile and synthesize existing …

Fire Regimes Of Montane Grasslands Of The Valles Caldera National Preserve, New Mexico, Donald A. Falk, Craig D. Allen, Robert Parmenter, Thomas Swetnam, Clifford Dils

Joint Fire Science Program Research Project Reports

Montane grasslands are an important ecosystem type in Southwestern landscapes, occurring from the forest borders of piñon-juniper woodland to high elevation subalpine and alpine ecosystems. Thus, they often represent a mosaic element embedded in the forest landscape matrix, playing key roles in processing water and nutrients, and providing habitat for unique suites of species, often at higher levels of diversity than those found in surrounding uplands. Soils, local temperature and moisture gradients, and disturbance all play roles in determining the distribution and extent of montane grasslands. Of these factors, fire plays the most dynamic role in regulating the location and …

Who Hits And Hoots At Whom? Potential For Interference Competition Between Barred And Northern Spotted Owls, Nicholas J. Van Lanen, Alan B. Franklin, Kathryn P. Huyvaert, Raoul F. Reiser Ii, Peter C. Carlson

United States Department of Agriculture Wildlife Services: Staff Publications

The northern spotted owl (Strix occidentalis caurina) is a controversial species in the Pacific Northwest that is listed as threatened under the Endangered Species Act. The barred owl (Strix varia), a species historically restricted to eastern North America, has recently expanded its range to completely overlap that of the northern spotted owl. Recent evidence suggests that barred owls may compete with northern spotted owls and may be one cause for recent declines in some northern spotted owl populations. Our focus was to examine whether barred owls have the potential to competitively exclude northern spotted owls from …

Estimating Age From Recapture Data: Integrating Incremental Growth Measures With Ancillary Data To Infer Age-At-Length, Mitchell J. Eaton, William A. Link

United States Geological Survey: Staff Publications

Estimating the age of individuals in wild populations can be of fundamental importance for answering ecological questions, modeling population demographics, and managing exploited or threatened species. Significant effort has been devoted to determining age through the use of growth annuli, secondary physical characteristics related to age, and growth models. Many species, however, either do not exhibit physical characteristics useful for independent age validation or are too rare to justify sacrificing a large number of individuals to establish the relationship between size and age. Length-at-age models are well represented in the fisheries and other wildlife management literature. Many of these models …

Estimating Age From Recapture Data: Integrating Incremental Growth Measures With Ancillary Data To Infer Age-At-Length, Mitchell J. Eaton, William A. Link

United States Geological Survey: Staff Publications

Estimating the age of individuals in wild populations can be of fundamental importance for answering ecological questions, modeling population demographics, and managing exploited or threatened species. Significant effort has been devoted to determining age through the use of growth annuli, secondary physical characteristics related to age, and growth models. Many species, however, either do not exhibit physical characteristics useful for independent age validation or are too rare to justify sacrificing a large number of individuals to establish the relationship between size and age. Length-at-age models are well represented in the fisheries and other wildlife management literature. Many of these models …

Cattle Grazing Reduces Survival And Reproduction Of The Western Prairie Fringed Orchid, Bonnie Warner Alexander, Donald Kirby, Mario Biondini, Edward Dekeyser

The Prairie Naturalist

QuantifYing impacts of livestock grazing and prairie management strategies on the threatened western prairie' fringed orchid (Platanthera praeclara) is difficult due to the erratic appearance of the orchid above-ground. We monitored above-ground survival of orchids from flowering to mature seed capsule production, comparing plant height, flower numbers, and seed capsule numbers from 2002-2004 in rotationally grazed pastures and non-grazed sites. Orchid survival differed significantly between grazed and non-grazed pastures, with the proportion of plants surviving from flower to capsule production consistently lower in grazed pastures. Mean orchid survival in grazed and non-grazed areas was 40% and 87%, respectively. …

Contributions Of Demography And Dispersal Parameters To The Spatial Spread Of A Stage-Structured Insect Invasion, Tom E. X. Miller, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Stage-structured models that integrate demography and dispersal can be used to identify points in the life cycle with large effects on rates of population spatial spread, information that is vital in the development of containment strategies for invasive species. Current challenges in the application of these tools include: (1) accounting for large uncertainty in model parameters, which may violate assumptions of ‘‘local’’ perturbation metrics such as sensitivities and elasticities, and (2) forecasting not only asymptotic rates of spatial spread, as is usually done, but also transient spatial dynamics in the early stages of invasion. We developed an invasion model for …

Pregnancy Intentions Among Women Who Do Not Try: Focusing On Women Who Are Okay Either Way, Julia Mcquillan, Arthur L. Greil, Karina M. Shreffler

Department of Sociology: Faculty Publications

Objectives: Are women who are intentional about pregnancy (trying to or trying not to get pregnant) systematically different from women who are “okay either way” about getting pregnant?
Methods. We use a currently sexually active subsample (n = 3,771) of the National Survey of Fertility Barriers, a random digit dialing telephone survey of reproductive-aged women (ages 25–45) in the United States. We compare women who are trying to, trying not to, or okay either way about getting pregnant on attitudes, social pressures, life course and status characteristics using bivariate analyses (chi-square tests for categorical and ANOVA tests for continuous variables). …

Evidence For Recent Population Bottlenecks In Northern Spotted Owls (Strix Occidentalis Caurina), W. Chris Funk, Eric D. Forsman, Matthew Johnson, Thomas D. Mullins, Susan M. Haig

United States Geological Survey: Staff Publications

The northern spotted owl (Strix occidentalis caurina) is one of the most controversial threatened subspecies ever listed under the US Endangered Species Act. Despite protection of its remaining forest habitat, recent field studies show continued declines of northern spotted owls. One potential threat to northern spotted owls which has not yet been shown is loss of genetic variation from population bottlenecks. Bottlenecks can increase the probability of mating among related individuals, potentially causing inbreeding depression, and can decrease adaptive potential. Here we report evidence for recent bottlenecks in northern spotted owls using a large genetic dataset (352 individuals …

Aging In America: Now And When, Laura Ihrig

Nebraska Anthropologist

The following paper is a study of aging in two societies, the United States and the traditional culture of the !Kung of western Botswana, Africa. The material reviewed includes current and projected population trends, cultural norms with regard to the elderly, and potential future implications of the gathered information. Resources consisted of journal articles, books, and government agency reports.

Increasing Retention Rates In Minority Librarians Through Mentoring, Antonia Olivas, Richard Ma

E-JASL: Electronic Journal of Academic and Special Librarianship (1999-2009, Volumes 1-10)

Thesis

Maintaining healthy mentoring relationships throughout librarians’ careers helps to increase retention rates among minority librarians and promotes diversity in upper-management.

Abstract

Recruitment of minority librarians has been at the forefront of library literature for decades. However, what happens to those librarians after they graduate from library school and get their first library jobs? Do they stay in the profession for long? Is there a support system to help them maintain the excitement and novelty of their career choice after they’ve been wooed by scholarships and residency programs? This article will discuss the results of a study conducted by librarians …

New Rural Residents: Insights Into Their Decision To Stay Or Leave, Charlotte Narjes, Cheryl A. Burkhart-Kriesel

Cornhusker Economics

What brought new residents to the Nebraska Panhandle? For many, it was the image of a small town environment, which they described as a family and faith oriented community, safe and free of traffic and congestion and often located closer to family.

This insight was one of many identified through twelve regional focus group interviews conducted by the University of Nebraska-Lincoln faculty as part of a research project funded by the United States Department of Agriculture-National Research Initiative.

While a number of individuals were pleased with the small town atmosphere, others found that their image of the community did not …

Moving To The Nebraska Panhandle: A Broad Picture Of The Decision Process, Charlotte Narjes

Cornhusker Economics

New residents to the Nebraska Panhandle compared and researched rural communities before making their decision to move. This was one of the themes that emerged in a qualitative study conducted by the University of Nebraska-Lincoln, funded by the United States Department of Agriculture CSREES National Research Initiative Grant program. The new movers not only compared communities, but they had choices, as one individual stated, “We spent about six months looking at different communities … we developed a formula … 50 percent job … 25 percent community, 25 percent school.”

Thirteen questions were asked to 78 new residents that participated in …

Community Vision Is Important To New Residents, Charlotte Narjes, Cheryl A. Burkhart-Kriesel

Cornhusker Economics

New residents to the Nebraska Panhandle want to see their communities succeed. To better understand the reasons new residents move to the Panhandle, twelve focus groups were held across the region. The focus groups are part of a University of NebraskaSLincoln research project funded by a 2006 grant from the United States Department of Agriculture National Research Initiative (USDA-NRI), looking at the characteristics and motivations of new residents in the eleven counties. The research project includes a demographic study, a mail survey to new residents, an iterative three-phase survey process to community development practitioners and a focus group of new …

The Impact Of The Atlantic Slave Trade On West Africa: Polygyny And Female Reproductive Success, Katherine Lamie

Nebraska Anthropologist

J.D. Fage (1969) and Patrick Manning (1981; 1990) examine demographic data from historical records, in the West African political and economic context, in order to formulate theories of the impact of the Atlantic slave trade on West African populations and social structure. However, Fage and Manning come to markedly different conclusions. Fage maintains that the intensification of polygyny in West Africa that accompanied the Atlantic slave trade preserved African populations. In contrast, Manning argues that intensified polygynous marriages on the West African coast decreased the fertility of female slaves, thereby depressing population growth and affecting traditional social structures. Manning later …

Conservation Biology For Suites Of Species: Demographic Modeling For Pacific Island Kingfishers, Dylan C. Kesler, Susan M. Haig

United States Geological Survey: Staff Publications

Conservation practitioners frequently extrapolate data from single-species investigations when managing critically endangered populations. However, few researchers initiate work with the intent of making findings useful to conservation efforts for other species. We presented and explored the concept of conducting conservation-oriented research for suites of geographically separated populations with similar natural histories, resource needs, and extinction threats. An example was provided in the form of an investigation into the population demography of endangered Micronesian kingfishers (Todiramphus cinnamominus). We provided the first demographic parameter estimates for any of the 12 endangered Pacific Todiramphus species, and used results to develop a …

Arthur Paul Afghanistan Collection Bibliography - Volume Ii: English And European Languages (2000), Shaista Wahab

Digitized Afghanistan Materials in English from the Arthur Paul Afghanistan Collection

In December 1995, the first volume of this bibliography was published. Volume I included all the Pashto and Dari language titles that were in the Arthur Paul Afghanistan Collection at that time. Volume II includes English and European language materials. This volume contains titles that were added to the Collection prior to January 1998. The Arthur Paul Afghanistan Collection is one of the largest collections of research materials on Afghanistan and serves scholars from around the world.

Changes In Co-Survivorship Of Adult Children And Parents: Ju/'Hoansi Of Botswana In 1968 And 1988, Patricia Draper, Nancy Howell

Department of Anthropology: Faculty Publications

Our study addresses these issues in a sociological microcosm that makes questions about population aging particularly interesting. The group on whom we report are the Ju|'hoansi (!Kung) of western Ngamiland, part of the Kalahari Desert of Botswana. They constitute a noteworthy case for several reasons. Discussion of modernization and its impact on the lives of elderly in traditional society has focused most often on agricultural and peasant societies, rather than on economically simpler groups such as hunter gatherers1). Ju|'hoansi, though now living in permanent settlements, have a recent past of mobile hunting and gathering. Over the past sixty years, Ju|'hoansi …

Infertility: Testing A Helpseeking Model, Lynn K. White, Julia Mcquillan, Arthur L. Greil, David R. Johnson

Bureau of Sociological Research: Faculty Publications

This paper uses data from a study of 196 infertile women from the Midwestern US to examine a general theory of help-seeking behavior applied to infertility. All of these women report meeting the medical definition of infertility—12 months or more of regular intercourse without conception—at some point in their lives. Only 35 percent of this sample of infertile women identified themselves as having had fertility problems and only 40 percent had sought medical treatment.

Drawing on prior theories of help-seeking, we examine the effects of symptom salience, life course cues, attitudes, predisposing factors, and enabling conditions on help-seeking. We posit …

Distinct Population Segments, Robin S. Waples

United States Department of Commerce: Staff Publications

In reflecting on how the U.S. Endangered Species Act (ESA) has dealt with biodiversity issues over the past thirty years, it is instructive to review the collection of fifty-seven papers in the 1988 volume by Wilson entitled Biodiversity (1988b). Anchored in time midway between enactment of the ESA in 1973 and the present (2006 and counting), Wilson's volume provides a snapshot of the issues related to biodiversity that occupied conservation biologists during the first half of these three decades. The vast majority (over 80 percent) dealt with higher levels of biological organization (species or ecosystems), while only two (less than …

Incorporating Animal Behavior Into Seed Dispersal Models: Implications For Seed Shadows, Sabrina E. Russo, Stephen Portnoy, Carol K. Augspurger

School of Biological Sciences: Faculty Publications

Seed dispersal fundamentally influences plant population and community dynamics but is difficult to quantify directly. Consequently, models are frequently used to describe the seed shadow (the seed deposition pattern of a plant population). For vertebrate dispersed plants, animal behavior is known to influence seed shadows but is poorly integrated in seed dispersal models. Here, we illustrate a modeling approach that incorporates animal behavior and develop a stochastic, spatially explicit simulation model that predicts the seed shadow for a primate-dispersed tree species (Virola calophylla, Myristicaceae) at the forest stand scale. The model was parameterized from field-collected data on …

Annual Publication Of The Department Of Agronomy And Horticulture 2006

Department of Agronomy and Horticulture: Annual Newsletters

CONTENTS

Alumni news . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Articles:

Agriculture biotechnology pipeline . . . . . . . . . . . . . . . . . . . . . . . . . 12

Come to Kimmel . . . . . . . . . . . . . . . . …

The Symmetry Of Longevity, Lawrence G. Harshman, Hans-Georg Müller, Xueli Liu, Yue Wang, James R. Carey

Lawrence G. Harshman Publications

We tested the hypothesis that relatively symmetrical flies live longer. Vein measurements on the left and right wings from the same individual were used to characterize bilateral symmetry in relationship to age-specific survival in defined cohorts. A longitudinal cohort study supported the hypothesis of a correlation between bilateral symmetry and longevity. For another type of experiment, wings were removed from females and males at approximately the beginning of adult life. Thus, there would be no effect of wings per se on adult survival. These wings were measured to characterize bilateral asymmetry, and the day of death of each dewinged individual …

Rural Depopulation: A Closer Look At Nebraska’S Counties And Communities, Randolph L. Cantrell

Rural Initiative Program: Publications and Reports

There is no question about it; rural population loss and Metropolitan concentration continue to be important factors in shaping social and economic conditions in much of America’s Great Plains region. Despite widespread population increases throughout much of nonmetropolitan America during the 1990s, the rural Great Plains has remained an area of persistent decline (Johnson and Beale, 1998 and 2001). Declining populations have characterized many Great Plains counties since the early 1900s, and the trend has continued with few exceptions through the most recent census in 2000. In fact, for some Great Plains counties, the rate of population decline has actually …

A Simulation Test Of The Effectiveness Of Several Methods For Error-Checking Non-Invasive Genetic Data, David A. Roon, Lisette P. Waits, Katherine C. Kendall

United States National Park Service: Publications

Non-invasive genetic sampling (NGS) is becoming a popular tool for population estimation. However, multiple NGS studies have demonstrated that polymerase chain reaction (PCR) genotyping errors can bias demographic estimates. These errors can be detected by comprehensive data filters such as the multiple-tubes approach, but this approach is expensive and time consuming as it requires three to eight PCR replicates per locus. Thus, researchers have attempted to correct PCR errors in NGS datasets using non-comprehensive error checking methods, but these approaches have not been evaluated for reliability. We simulated NGS studies with and without PCR error and ‘filtered’ datasets using non-comprehensive …

Amphibian Research And Monitoring Initiative: Concepts And Implementation, Paul Stephen Corn, Michael J. Adams, William A. Battaglin, Alisa L. Gallant, Daniel L. James, Melinda Knutson, Catherine A. Langtimm, John R. Sauer

United States Geological Survey: Publications

This report provides the basis for discussion and subsequent articulation of a national plan for the Amphibian Research and Monitoring Initiative (ARMI). The authors were members of a task force formed from within the U.S. Geological Survey (USGS) that included scientists with expertise in biology, cartography, hydrology, and statistics. The assignment of the task force was to extend work begun by the National Amphibian Leadership Group. This group, composed of senior USGS scientists, managers, and external authorities, met in Gainesville, Florida, in February 20001. The product of this meeting was a document outlining the framework for a national program to …

The Nuclear Reddening Curve For Active Galactic Nuclei And The Shape Of The Infrared To X-Ray Spectral Energy Distribution, C. Martin Gaskell, René W. Goosmann, Robert R. J. Antonucci, David H. Whysong

Department of Physics and Astronomy: Faculty Publications

We present extinction curves derived from the broad emission lines and continua of samples of 72 radio-loud and 1018 radio-quiet active galactic nuclei (AGNs). The curves are significantly flatter in the UV than curves for the local interstellar medium. The reddening curves for the radio-quiet Large Bright Quasar Survey quasars are slightly steeper than those of the radio-loud quasars in the UV, probably because of additional reddening by dust farther out in the host galaxies of the former. The UV extinction curves for the radio-loud AGNs are very flat. This is explicable with slight modifications to standard Mathis-Rumpl-Nordsieck dust models: …

Help-Seeking Patterns Among Subfecund Women, Arthur L. Greil, Julia Mcquillan

Bureau of Sociological Research: Faculty Publications

A random sample of women in the midwestern United States was studied in order to provide a fuller picture of the ways in which US women responded to subfecundity. Using a biomedical definition of infertility, we examined women who did not conceive within 12 months of unprotected intercourse whether they were trying to get pregnant or not. Of the 196 ever-subfecund women in our sample, 123 experienced subfecundity while trying to get pregnant; we called these “subfecund with intent.” Another 73 women experienced subfecundity while not actively trying to get pregnant; we called these “subfecund without intent.” Of the 196 …

Journal Of Women In Educational Leadership, Vol. 1, No. 2 - April 2003

Journal of Women in Educational Leadership

No abstract provided.

"I Have Work To Do" Work Roles And Affirming Or Marginalizing Experiences Among Women At Professor Rank, Florence A. Hamrick

Journal of Women in Educational Leadership

This qualitative study of women at professor rank at a Research Extensive university explored work roles as well as occasions and events that signified affirmation or marginalization to respondents as they performed their work. Three primary work roles emerged: disciplinary expert, mentor or model, and advisor or change agent. Although all respondents clearly identified themselves as disciplinary experts, the other two roles were often more complex. Respondents generally experienced affirmation through student, collegial,and institutional recognitions of expertise and effectiveness. Marginalizing experiences included serving token roles on committees or other bodies and being a "lone voice" on issues of equity.