The survival and growth of shortleaf pine systems in the Missouri Ozarks : effects of competition, genetics, and site preparation

Establishing shortleaf pine (Pinus echinata) across portions of its historical range has proven challenging due to shade intolerance, slow early growth, and poor competitive ability. The objectives of this study were to determine the expected survival and growth rates of planted shortleaf pine relative to artificial and natural hardwoods, identify barriers to regeneration success, and develop tools for individual tree assessment. Data from three long-term studies in southeastern Missouri were used to examine the survival and growth of over 5500, 1-0 seedlings as a function of understory competition, overstory density, genetic selection, and site preparation in artificially and naturally regenerated stands. Growth of planted 1-0 shortleaf pine exceeded that of planted 1-0 white oak (Quercus alba) and northern red oak (Q. rubra) when grown in the open during a 22-year monitoring period. However, during the first 10 years, planted shortleaf pine had lower survival and height growth where competing with natural oaks and other hardwood regeneration originating from advance reproduction rather than planted seedlings. Regression analysis indicated that height and diameter growth in natural stands was further reduced by retaining a hardwood overstory, while survival was not. Planted shortleaf pine grows faster than planted oaks in open stands with few other hardwood competitors. However, most regeneration occurs in mixed hardwood stands where large advance reproduction outcompetes planted shortleaf pine after harvesting. Due to the variation encountered in shortleaf pine growth, height-growth percentiles present an opportunity to assess and classify individual trees, while allowing for predictions to be made about future growth potential.by Stephen John LyczakIncludes bibliographical reference

Arithmetic of affine del Pezzo surfaces

In this thesis integral points on affine del Pezzo surfaces are studied. The first two chapters offer a review of arithmetic techniques and del Pezzo surfaces, but also a novel approach to del Pezzo surfaces using a new type of surface, namely the peculiar del Pezzo surface. This allows one to study del Pezzo surfaces by considering linear subsystems of cubic plane curves.In Chapter 3 a uniform bound is given for the Brauer group of certain affine del Pezzo surfaces over number fields. This answers an open question for the geometrically related K3 surfaces. While determining this bound techniques are described for (partially) computing these groups.Chapter 4 begins with constructing models of del Pezzo surfaces; not by geometrically manipulating the projective plane over the rationals and taking the flat closure over the integers, but by manipulating schemes over the integers. The advantage of this approach is that one can control the reduction of the surface over all primes. Using these techniques and the computations from Chapter 3 we describe families of surfaces with an order 5 Brauer-Manin obstruction to the integral Hasse principle. These stand out against previously published examples, since these were all of lower order.Number theory, Algebra and Geometr

Exploring The Relationship Between Faculty Perceptions Of Chairperson-Faculty Member Communication Exchanges And Department Climate

Leadership communication has many consequences: those that affect an organization and its outcomes, and those that affect the followers. In academia, one of the most important leadership roles is that of the departmental chairperson. Through her or his communication, the academic chairperson influences nearly every aspect of departmental life for faculty, including organizational climate. In fact, it can be argued that the chairperson helps both create and sustain the department climate for faculty. One perspective of leadership and communication posits that leadership is enacted in the dyadic communication that occurs between the leader and the follower. According to Leader Member Exchange Theory, leaders fail to treat their followers (which it calls members ) equally, and this is enacted in their communication. In-group members experience more open and supportive communication from their leaders and thus have better personal and professional organizational experiences, while out-group members have less open and supportive communication from their leaders and thus have more negative personal and professional organizational experiences. One antecedent to in-group and out-group communication is similarity; in many cases, the more similar individuals are to one another, the more open their communication is. Research in the business sector has determined that leader-member communication is related to perceptions of organizational climate. However, little research has been done in higher education to understand the relationship between chairperson-faculty communication and organizational climate, nor on the role of similarity in chairperson-faculty communication. Consequently, the current study sought to understand the relationship between demographic similarity, perceptions of in-group and out-group membership, and perceptions of department climate in chairperson-faculty relationships in higher education. Faculty in communication departments from higher education institutions across the United States participated in the current study (n=410). An online, 66-item survey gathered information about faculty perceptions of their in-group or out-group status, their perceptions of their departmental climate, their chairperson\u27s ethnicity, biological sex, and sexual orientation, and their own ethnicity, biological sex, and sexual orientation to answer four research questions: What is the nature of the relationship between faculty perceptions of department chairperson-faculty member communication exchanges and the department climate?; Do faculty perceptions differ significantly by biological sex?; Do faculty perceptions differ significantly by ethnicity?; Do faculty perceptions differ significantly by sexual orientation? Statistical analysis of the data revealed a significant relationship between faculty perceptions of department chairperson-faculty member communication exchanges and the department climate. Faculty perceptions did not differ significantly by biological sex, ethnicity, or sexual orientation. The results suggest a need for further research on the topic to understand the relationship between similarity, leader-member communication, and department climate

Inquilinus limosus in Patients with Cystic Fibrosis, Germany

We identified Inquilinus limosus, a recently described α-proteobacterium, in sputum of 2 patients with cystic fibrosis whose respiratory tracts were persistently colonized for >9 months. We present data on the epidemiology, antimicrobial susceptibility, and molecular characteristics of I. limosus

Systematic genetic analysis of the MHC region reveals mechanistic underpinnings of HLA type associations with disease.

The MHC region is highly associated with autoimmune and infectious diseases. Here we conduct an in-depth interrogation of associations between genetic variation, gene expression and disease. We create a comprehensive map of regulatory variation in the MHC region using WGS from 419 individuals to call eight-digit HLA types and RNA-seq data from matched iPSCs. Building on this regulatory map, we explored GWAS signals for 4083 traits, detecting colocalization for 180 disease loci with eQTLs. We show that eQTL analyses taking HLA type haplotypes into account have substantially greater power compared with only using single variants. We examined the association between the 8.1 ancestral haplotype and delayed colonization in Cystic Fibrosis, postulating that downregulation of RNF5 expression is the likely causal mechanism. Our study provides insights into the genetic architecture of the MHC region and pinpoints disease associations that are due to differential expression of HLA genes and non-HLA genes

Bacteriophages ϕMR299-2 and ϕNH-4 Can Eliminate Pseudomonas aeruginosa in the Murine Lung and on Cystic Fibrosis Lung Airway Cells

Pseudomonas aeruginosa is a common cause of infection in the lungs of patients with cystic fibrosis (CF). In addition, biofilm formation and antibiotic resistance of Pseudomonas are major problems that can complicate antibiotic therapy. We evaluated the efficacy of using bacteriophages to kill the pathogen in both biofilms and in the murine lung. We isolated and characterized two phages from a local wastewater treatment plant, a myovirus (ϕNH-4) and a podovirus (ϕMR299-2). Both phages were active against clinical isolates of P. aeruginosa. Together, the two phages killed all 9 clinical isolate strains tested, including both mucoid and nonmucoid strains. An equal mixture of the two phages was effective in killing P. aeruginosa NH57388A (mucoid) and P. aeruginosa MR299 (nonmucoid) strains when growing as a biofilm on a cystic fibrosis bronchial epithelial CFBE41o- cell line. Phage titers increased almost 100-fold over a 24-h period, confirming replication of the phage. Furthermore, the phage mix was also effective in killing the pathogen in murine lungs containing 1 × 107 to 2 × 107 P. aeruginosa. Pseudomonas was effectively cleared (reduced by a magnitude of at least 3 to 4 log units) from murine lungs in 6 h. Our study demonstrates the efficacy of these two phages in killing clinical Pseudomonas isolates in the murine lung or as a biofilm on a pulmonary cell line and supports the growing interest in using phage therapy for the control and treatment of multidrug-resistant Pseudomonas lung infections in CF patients