An Analysis of Anchitherine Equids Across the Eocene–Oligocene Boundary in the White River Group of the Western Great Plains

Anchitherine horses are a subfamily of equids that are abundantly represented in the late Eocene and early Oligocene of North America. This group has been heavily studied in the past, but important questions still remain. Some studies have focused on the Eocene-Oligocene boundary and have used these equids along with other taxa to study mammalian diet and climate change through this interval. I reexamine two anchitherine genera, Mesohippus and Miohippus, from stratigraphic sequences of the White River Group in western Nebraska and southwestern South Dakota. These sequences span the Chadronian (late Eocene), Orellan (early Oligocene), and Whitneyan (early Oligocene) North American land-mammal ages. The most recent revision of these genera was done by Prothero and Shubin (1989). I review the characters used for taxonomic identification. This includes characters such as the hypostyle, the articular facet on the third metatarsal, and dental dimensions. To avoid possible biases caused by combining specimens from different stratigraphic levels, specimens were separated by location and stratigraphic level. The length and width of cheek teeth, and tooth rows were measured on 488 specimens. First molar area serves as a proxy for body mass in horses and other mammals, and can be useful for distinguishing among species. Results indicate that the characters used by Prothero and Shubin were highly variable in anchitherine horses and are not useful for distinguishing between these genera. The development of the articular facet on the third metatarsal may be a function of body size and therefore may be of no more utility than first molar area. Variability in first molar area suggests the presence of three species in the medial and late Chadronian, two species in the Orellan, and at least two species in the Whitneyan. Due to a lack of objective criteria separating Mesohippus from Miohippus, I recommend synonymy of these genera, making Mesohippus a junior subjective synonym.

The Perception of Natural, Cell Phone, and Computer-Synthesized Speech During The Performance Of Simultaneous Visual-Motor Tasks

This study investigated the influence of top-down and bottom-up information on speech perception in complex listening environments. Specifically, the effects of listening to different types of processed speech were examined on intelligibility and on simultaneous visual-motor performance. The goal was to extend the generalizability of results in speech perception to environments outside of the laboratory. The effect of bottom-up information was evaluated with natural, cell phone and synthetic speech. The effect of simultaneous tasks was evaluated with concurrent visual-motor and memory tasks. Earlier works on the perception of speech during simultaneous visual-motor tasks have shown inconsistent results (Choi, 2004; Strayer & Johnston, 2001). In the present experiments, two dual-task paradigms were constructed in order to mimic non-laboratory listening environments. In the first two experiments, an auditory word repetition task was the primary task and a visual-motor task was the secondary task. Participants were presented with different kinds of speech in a background of multi-speaker babble and were asked to repeat the last word of every sentence while doing the simultaneous tracking task. Word accuracy and visual-motor task performance were measured. Taken together, the results of Experiments 1 and 2 showed that the intelligibility of natural speech was better than synthetic speech and that synthetic speech was better perceived than cell phone speech. The visual-motor methodology was found to demonstrate independent and supplemental information and provided a better understanding of the entire speech perception process. Experiment 3 was conducted to determine whether the automaticity of the tasks (Schneider & Shiffrin, 1977) helped to explain the results of the first two experiments. It was found that cell phone speech allowed better simultaneous pursuit rotor performance only at low intelligibility levels when participants ignored the listening task. Also, simultaneous task performance improved dramatically for natural speech when intelligibility was good. Overall, it could be concluded that knowledge of intelligibility alone is insufficient to characterize processing of different speech sources. Additional measures such as attentional demands and performance of simultaneous tasks were also important in characterizing the perception of different kinds of speech in complex listening environments.

The Role of CEO Statements of Aggressiveness and the Competitive Aggressiveness of Firms: What is the Impact on Performance?

This research examines the impact of a CEO’s statements of aggressiveness on his or her organization’s competitive moves and subsequent performance. Hypotheses were developed based on previous work in Upper Echelon Theory and competitive dynamics. Based on this prior literature, it was hypothesized aggressive statements by CEOs will be associated with more aggressive organizations. It was also hypothesized these more aggressive organizations would display better performance than less aggressive organizations. A content analysis of letters to shareholders and trade publications was performed. This data was analyzed using multiple regression in SPSS 17 to test the hypotheses that aggressive statements by CEOs are associated with aggressive organizations and higher performance. Aggression scores for the content analysis were generated using the software package DICTION. The sample for the study was the organizations with the most revenue in two industries, automobile manufacturing and retailing. Data collection covered a five-year time span from 2003-2007, with performance data lagged one year. Control variables employed included CEO tenure, CEO background, organization size, and organization age. The findings indicate that CEO statements of aggressiveness do not significantly impact the competitive aggressiveness or the performance of their organizations. The implications of these findings are discussed and potential avenues for future research in the area are outlined.

The Somatic Chromosomes of Some North American Marmots (Sciuridae), with Remarks on the Relationships of Marmota browerii Hall and Gilmore

Karyotypes are defined for two nearctic species of marmots, Marmota olympus (2n = 40) and M. vancouverensis (2n = 42), and supplemental information is included on the karyotypes of M. flaviventris, M. monax ochracea, and M. marmota. The six North American species of Marmota (NF = 66) comprise a distinct group as compared with the middle Asian species (NF = 70) for which the karyotypes are known. Karyologic findings and zoogeographic evidence based upon the distribution of two nearctic species of host-specific cestodes indicate that M. broweri, in northern Alaska, is a pre-Würm relict. Its affinities appear to be with the North American caligata-group rather than with the northeastern Siberian M. camtschatica. The occurrence on M. broweri of the Asian flea, Oropsylla silantiewi, has not been explained. Some ecological and behavioral characteristics of M. broweri are briefly described and compared with those of other species. Family groups of M. broweri hibernate together in single winter dens that are plugged at the entrance; copulation takes place before the animals emerge from the winter den, near mid-May; face-glands are utilized in marking of territory. French abstract: Les auteurs définissent les caryotypes de deux espèces néarctiques de marmottes, Marmota olympus (2n=40) et M. vancouverensis (2n=42), et donnent des précisions sur les caryotypes de M. flaviventris, M. monax ochracea et M. marmota. Les six especes de Marmota (NF=66) d'Amérique du Nord forment un groupe distinct des espèces d'Asie centrale (NF=70) dont Ie caryotype est connu. Les données caryologiques et les preuves zoogéographiques basées sur la répartition de deux espèces néarctiques de cestodes spécifiques de I'hôte démontrent que M. broweri, dans l'Alaska septentrional, est une relicte du pré-Würm. Elle semble avoir plus d'affinités avec Ie groupe nord américain de caligata qu'avec M. camtschatica du nord de la Sibérie. La présence sur M. broweri de la puce asiatique, Oropsylla silantiewi, n'est pas expliquée. Quelques caractéristiques écologiques et éthologiques de M. broweri sont décrites brièvement et comparées avec celles d'autres espèces. Les groupes familiaux de M. broweri hibernent dans un meme terrier dont l'entrée est bouchée; la copulation à lieu avant que les animaux sortent de leur abri hivernal, it la mi-mai ; ils se servent de leurs glandes faciales pour marquer leur territoire.

Is Everyone Rated Equal? An Examination of Factors Related to Sexual Risk in Ethnically Diverse Male Adolescents Who Have Sexually Offended

As the juvenile justice system has evolved, there has been a need for clinicians to make judgments about risk posed by adolescents who have committed sexual offenses. There are inherent difficulties in attempting to assess risk for violence among adolescents due to the developmental changes taking place and the absence of well-validated instruments to guide risk prediction judgments. With minority groups increasing in numbers in the U.S., it is likely that professionals will encounter minority individuals when conducting risk assessments. Overall questions regarding race/ethnicity have been neglected and there are few if any published research that explores risk factors with minority juvenile sex offenders. The present study examined whether differences exist between Caucasian and racial/ethnic minority adolescent sexual offenders on four risk assessment measures (J-SORRAT-II, J-SOAP-II, SAVRY, and ERASOR). The sample of 207 male adolescent sexual offenders was drawn from treatment facilities in a Midwestern state. Overall results indicated that minority adolescent sex offenders had fewer risk factors endorsed than Caucasian youth across all risk assessment tools. Exploration of interactions between race and factors such as: family status, exposure to family violence, and family history of criminality upon the assessment tools risk ratings yielded non-significant findings. Limitations, suggestions for future directions, and clinical implications are discussed.

Ecology, stable isotopes, and management of grassland songbirds at National Park Service properties on the Great Plains

Grassland ecosystems have been severely reduced and grassland bird populations have experienced consistent declines. National Park Service (NPS) properties on the Great Plains provide breeding habitat for grassland songbirds, though little is known about the quality of this habitat. A short-term study on songbirds at three NPS properties complemented current monitoring, providing an among park comparison addressing grassland bird productivity and fidelity relative to NPS property size. During 2008-2009, I assessed avian species richness, and estimated bird density and grassland songbird nest success. Bird species richness was greatest at small and medium sites, while number of nesting obligate species was greatest at the large site. Species-specific densities varied among sites, with few grassland obligates occurring at all three sites. Nest success estimates for grassland obligates were highest at the small site and lower at the large site. Another method to quantify habitat quality is assessment of breeding site fidelity. Current extrinsic markers used in monitoring site fidelity are inadequate for small birds; stable isotope analyses provide an alternative. I compared two techniques for assigning stable isotope tissue origin and measured grassland songbird site fidelity. My method of assigning origin provided site-specific variances of expected stable isotope values, an improvement over the most commonly used method. Fidelity tended to be higher at the large site, which may indicate a more robust breeding community of grassland birds. The small size of two of my sites precluded large sample sizes and made strong inferences difficult. To quantify how scientists cope with weak inference, I conducted a literature review. Strong inference was rarely observed, and most authors of weak-inference papers provided specific management recommendations. I suggest that adaptive management is an ideal method to resolve uncertainty from weak inference. Managers should consider my results within the context of regional and global management and the extent to which their unit might aide songbird conservation.

Impact of Bottom Flange Confinement Reinforcement on Performance of Prestressed Concrete Bridge Girders

For many years AASHTO provided no recommendation to state DOT’s on bottom flange confinement reinforcement for their bridge superstructures. The 1996 edition of AASHTO Standard Specification for Highway Bridges stated that nominal reinforcement be placed to enclose the prestressing steel from the end of the girder for at least a distance equal to the girder’s height. A few years later the 2004 AASHTO LRFD Bridge Design Specification changed the distance over which the confinement was to be distributed from 1.0h to 1.5h, and gave minimum requirements for the amount of steel to be used, No.3 bars, and their maximum spacing, not to exceed 6”. Research was undertaken to study what impact, if any, confinement reinforcement has on the performance of prestressed concrete bridge girders. Of particular interest was the effect confinement had on the transfer length, development length, and vertical shear capacity of the fore mentioned members. First, an analytical investigation was performed on the subject, and then an experimental investigation followed which consisted of designing, fabricating, and testing eight tee-girders and three NU1100 girders with particular attention paid to the amount and distribution of confinement reinforcement placed at the end of each girder. The results of the study show: 1) neither the amount or distribution of confinement reinforcement had a significant effect on the initial or final transfer length of the prestress strands; 2) at the AASHTO calculated development length, no significant impact from confinement was found on either the nominal flexural capacity of bridge girders or bond capacity of the prestressing steel; 3) the effects from varied confinement reinforcement on the shear resistance of girders tested was negligible, however, distribution of confinement did show to have an impact on the prestressed strands’ bond capacity; 4) confinement distribution across the entire girder did increase ductility and reduced cracking under extreme loading conditions.

Measurement, Simulation, and Analysis of the Mechanical Response of Railroad Track

Increased railroad traffic volumes, speeds, and axle loads have created a need to better measure track quality. Previous research has indicated that the vertical track deflection provides a meaningful indicator of track integrity. The measured deflection can be related to the bending stresses in the rail as well as characterize the mechanical response of the track. This investigation summarizes the simulation, analysis and development of a measurement system at the University of Nebraska (UNL) to measure vertical track deflection in real-time from a car moving at revenue speeds. The UNL system operates continuously over long distances and in revenue service. Using a camera and two line lasers, the system establishes three points of the rail shape beneath the loaded wheels and over a distance of 10 ft. The resulting rail shape can then be related to the actual bending stress in the rail and estimate the track support through beam theory. Finite element simulations are used to characterize the track response as related to the UNL measurement system. The results of field tests using bondable resistance strain gages illustrate the system’s capability of approximating the actual rail bending stresses under load.

A Pilot Study of the Relationship of Calcium Intake and Frequency of Injuries In High School Athletes

Little information is available related to adolescent calcium intake and relationships with injuries they might suffer from sport participation. To determine calcium intake of high school athletes, to assess their self reported injury rates, and to examine the relationship between the two over a 12 month period of time. Participants received a questionnaire at their school and completed it anywhere they found convenient. Adolescent athletes in the Lincoln Public School system (n=43) that participated in at least one sport in the past year. Four age groups participated in the study with sixteen year olds having a significantly higher calcium intake at 1297 mg that of fourteen year olds. A variety of sports were represented with largest number of respondents participating in baseball/or softball at (55%). The next most played sport was basketball at (18%). Median total diet calcium was 1144.5 mg with a mean of 1182 mg + 567 mg. For the frequency of injuries that caused a missed practice or game in the past year, ankle injuries were the most common (25%). Knee injuries were the second most common (17%), followed closely by hand injuries (8%). Mean total diet calcium of athletes with five or more injuries that caused a missed practice or game was significantly higher at 1966 mg (P<.05) than athletes mean diet calcium with zero, one, two, and three injuries. Total milk calcium of those who reported three injuries that resulted in broken or fractured bones or dislocated joints was significantly higher (P<.05) at 1286 mg of total milk calcium than those who reported having zero, one, or two breaks or fractures. Athletes with higher calcium intakes have a higher number of reported injuries. This may be the result of increased vigorous activity which leads to increased calorie and calcium consumption. More importantly, this increased activity leads to an increased chance of injury. The greater calcium intake correlated with greater number of injuries may also be because of third parties advising the athletes who get injured to drink more milk and get more calcium in their diets because they have been injuries already.

“PROVINCIALISM, PICKING SIDES AND BIAS: EFFECTS OF GEOGRAPHY ON MEDIA COVERAGE OF CRYSTAL BRIDGES MUSEUM OF AMERICAN ART, 2005-10.”

The development of Crystal Bridges Museum of American Art in Bentonville, Arkansas, by Wal-Mart heiress Alice Walton has prompted diverse coverage from print and online media. This investigation looked at trends in news stories and commentary from 2005-10 to show how the location of a medium affected coverage. Through the author’s own observations and interviews with journalists and other interested parties, several trends emerged. Media outlets outside Arkansas portrayed the museum as trying to plunder the cultural heritage of local communities and relied partly on the museum’s association with Wal-Mart and stereotypes of Arkansas to frame coverage. Arkansas media, faced with limited cooperation from the museum’s public relations apparatus, typically played a cheerleader role, at times overemphasizing the importance of the collection in the art world and showcasing few critical voices in stories about acquisitions and other areas of the museum’s development.

Predicting Problematic Approach Behavior Toward Politicians: Exploring the Potential Contributions of Control Theory

The potential merits of Carver and Scheier's (1981) control theory in the prediction of targeted violence are reviewed and several novel indicators of risk that are consistent with this theory are suggested for study. It was hypothesized that: (a) similarity between inappropriate contact with politicians and extremist group literature and writings; (b) the temporal proximity to violent or otherwise criminal actions and notable anniversaries of such groups; (c) detailed specification of a plan to engage in problematic approach behavior, and; (d) self-focus, will be significant predictors of problematic approach behavior. A sample of 506 individuals who engaged in threatening or otherwise inappropriate contact toward members of the United States Congress was drawn from the case files of the United States Capitol Police. Results of the present research indicated that detailed specification of a plan to engage in problematic approach behavior was strongly predictive of actually engaging in problematic approach. Furthermore, high self-focus was significantly related to problematic approach between-persons, although within-person, higher-than-average self-focus showed no such relation. Neither temporal proximity to notable acts of extremist violence nor similarity to known extremist group writings was found to be associated with problematic approach in this sample.

THE INFLUENCE OF CHILDHOOD ABUSE ON LONGITUDINAL COURSE OF RECOVERY IN PSYCHIATRIC REHABILITATION

Background: Empirical outcome studies have identified specific symptomatic, cognitive, emotional and functional sequelae of childhood abuse in people with severe mental illness (SMI). These findings illuminate the need for an integrated understanding of biological, psychological, environmental, and developmental aspects of SMI. Purpose: The purpose of the present study includes the following: 1) to examine reliability and validity of the comprehensive child abuse rating system in a sample of individuals with SMI, 2) to examine the influence of childhood abuse severity on recovery of psychotic symptoms, neurocognition and social-cognition, and social functioning in people with SMI during 12 months of inpatient psychiatric rehabilitation, and 3) to examine moderating effects of social cognition on the relationship between severity of different types of child abuse history and social functioning. Results: In Study I (N=171), the child abuse rating system produced reliable ratings and some subtypes of child abuse history were related to poorer premorbid functioning and cognition, higher overall psychiatric symptoms, and lower social functioning. In Study II (N=161), the longitudinal factor pattern invariance of the measures of social functioning, externality, and psychiatric symptoms were confirmed across 3 time points (e.g., at admission, at 6 months, and at 12 months). In addition, significant but varied linear relationships between subtypes of child abuse and each level of assessment of functioning were identified. In Study III (N=143), the results showed that higher baseline social inference, independent of history of child physical abuse (CPA), played a protective role in improvements in social functioning. High externality appeared to be counter-therapeutic for individuals with no history of CPA but protective for individuals with a more severe history of CPA. Conclusion: The child abuse rating system appears to provide reliable and valid assessment of subtypes of child abuse history of individuals with SMI. Considering the extreme heterogeneity in both SMI and child maltreatment, the current finding sheds light on providing individualized treatment and assessment planning for individuals with SMI and a history of childhood abuse.

Student Leader LMX Relationships as Moderated by Constructive-Developmental Theory

This study examined how the quality of Leader-Member Exchange (LMX) relationships was moderated by the Constructive-Developmental stage or Order of Consciousness of both leader and follower. Using student organization presidents and officers on a small, private, liberal arts college campus in the Midwest, the researcher used a sample of 37 students to study the impact developmental stage had on the leadership relationship. Using the Leader Member Exchange-Multi-Dimensional Measure (LMX-MDM), four dimensions of LMX were examined. The four dimensions were Affect, Contribution, Loyalty and Professional Respect. There was no significant relationship between Order of Consciousness and quality of LMX relationship. While there was no significant difference in LMX relationship based on gender of participants, there was a significant difference between how male presidents and officers perceived their relationship in the Loyalty dimension. Directions for further research and implications for practice were discussed.

Department of Veterinary and Biomedical Sciences: 2000 Annual Report

Foreword, 2000 John A . Schmitz. Professor and Department Head Veterinary and Biomedical Sciences Personnel Faculty Profiles Teaching program Research program Extension Program Nebraska Veterinary and Diagnostic Laboratory Systems Grants and Contracts Funded or Active in 2000 Patents by VBMS Faculty in 2000 Publications by VBMS Faculty in 2000 Presentations by VBMS Faculty in 2000 Articles Regarding the Department in 2000 Selected Committees, Editorial and Other Appointments of VBMS Faculty Departmental Budget Summaries Nebraska Agricultural Statistics 1999

INFLUENCE OF TYPE 2 BOVINE VIRAL DIARRHEA VIRUS NPRO ON ENHANCEMENT OF BOVINE RESPIRATORY SYNCYTIAL VIRUS REPLICATION MEDIATED BY ANTAGONISM OF HOST CELL INTERFERON TYPE I RESPONSES

Bovine viral diarrhea virus (BVDV) is a member of the genus Pestivirus, Family Flaviviridae. The virus can infect many species of animals of the order Artiodactyla. The BVDV genome encodes an auto protease, Npro, that degrades interferon regulatory factor-3 (IRF-3) reducing type I interferon (IFN-I) production from host cells. Bovine respiratory syncytial virus (BRSV) is a member of the genus Pneumovirus, Family Paramyxoviridae. Concurrent infection with BVDV and BRSV causes more severe respiratory and enteric disease than infection with either virus alone. Our hypothesis was that Npro modulates the innate immune responses to BVDV infection and enhances replication of BVDV or BRSV co-infection. The noncytopathic BVDV2 viruses NY93/c N- Npro 18 EGFP (a mutant with modified Npro fused with enhanced green fluorescent protein), NY93 infectious clone (NY93/c), wild-type NY93-BVDV2 (NY93-wt), and BRSV were evaluated in this study. The objectives of this study were: (1) to characterize the replication kinetics and IFN-I induction in Madin-Darby bovine kidney (MDBK) cells following infection with each of the BVDV isolates, and (2) to characterize the influence of BVDV-mediated IFN-I antagonism on enhancement of BRSV replication in bovine turbinate (BT) cells. NY93/c N- Npro 18 EGFP replicated 0.4 – 1.6 TCID50 logs lower than NY93-wt in MDBK cells. NY93/c N- Npro 18 EGFP-infected MDBK cells synthesized IFN-I significantly higher than NY93/c- and NY93-wt-infected MDBK cells. BT cells co-infected with NY93/c N- Npro 18 EGFP/BRSV or NY93-wt/BRSV were evaluated to determine the effects of co-infection on BRSV replication and IFN-I induction in BT cells. BRSV RNA levels in NY93-wt/BRSV co-infected BT cells were 2.49, 2.79, and 2.89 copy number logs significantly greater than in NY93/c N- Npro 18 EGFP/BRSV co-infected BT cells on days 5, 7, and 9 post-infection, respectively. BVDV RNA levels in NY93/c N- Npro 18 EGFP-infected BT cells were 1.64 – 4.38 copy number logs lower than in NY93-wt-infected BT cells. NY93/c N- Npro 18 EGFP single and co-infected BT cells synthesized IFN-I significantly higher than NY93-wt single and co-infected BT cells. In summary, these findings suggest: (1) NY93/c N- Npro 18 EGFP BVDV2 induced higher levels of IFN-I than BVDV2-wt and may be useful as a safer, replicating BVDV vaccine, and (2) Enhancement of BRSV infection by BVDV co-infection is mediated by antagonism of IFN-I.