Electron microscopic and biochemical characterization of Fraction 1 protein

High resolution electron microscopy of Fraction I protein from plant leave

Cryptic Repeated Genomic Recombination During Speciation in Gossypium gossypioides

The Mexican cotton Gossypium gossypioides is a perplexing entity, with conflicting morphological, cytogenetic, and molecular evidence of its phylogenetic affinity to other American cottons. We reevaluated the evolutionary history of this enigmatic species using 16.4 kb of DNA sequence. Phylogenetic analyses show that chloroplast DNA (7.3 kb), nuclear ribosomal internal transcribed spacers (ITS; 0.69 kb), and unique nuclear genes (8.4 kb) yield conflicting resolutions for G. gossypioides. Eight low-copy nuclear genes provide a nearly unanimous resolution of G. gossypioides as the basalmost American diploid cotton, whereas cpDNA sequences resolve G. gossypioides deeply nested within the American diploid clade sister to Peruvian G. raimondii, and ITS places G. gossypioides in an African (rather than an American) clade. These data, in conjunction with previous evidence from the repetitive fraction of the genome, implicate a complex history for G. gossypioides possibly involving temporally separated introgression events from genetically divergent cottons that are presently restricted to different hemispheres. Based on repetitive nuclear DNA, it appears that G. gossypioides experienced nuclear introgression from an African species shortly after divergence from the remainder of the American assemblage. More recently, hybridization with a Mexican species may have resulted in cpDNA introgression, and possibly a second round of cryptic nuclear introgression. Gossypium gossypioides provides a striking example of the previously unsuspected chimeric nature of some plant genomes and the resulting phylogenetic complexity produced by multiple historical reticulation events

Structures of complexes comprised of Fischerella transcription factor HetR with Anabaena DNA targets

HetR is an essential regulator of heterocyst development in cyanobacteria. Many mutations in HetR render Anabaena incapable of nitrogen fixation. The protein binds to a DNA palindrome upstream of hetP and other genes. We have determined the crystal structures of HetR complexed with palindromic DNA targets, 21, 23, and 29 bp at 2.50-, 3.00-, and 3.25-Å resolution, respectively. The highest-resolution structure shows fine details of specific protein–DNA interactions. The lower-resolution structures with longer DNA duplexes have similar interaction patterns and show how the flap domains interact with DNA in a sequence nonspecific fashion. Fifteen of 15 protein–DNA contacts predicted on the basis of the structure were confirmed by single amino acid mutations that abolished binding in vitro and complementation in vivo. A striking feature of the structure is the association of glutamate 71 from each subunit of the HetR dimer with three successive cytosines in each arm of the palindromic target, a feature that is conserved among all known heterocyst-forming cyanobacteria sequenced to date

IDENTIFYING REASONS FOR ATTRITION AT THE CLEMENTE COURSE IN THE HUMANITIES, WORCESTER, MA

This paper identifies reasons for attrition and possible solutions to higher retention at the Clemente Course in the Humanities, Worcester (Clemente). Over the last four years, since the re-launch of the Clemente, the retention rate of students completing the program has remained around 50%. Clemente is an alternative, adult education program that provides college level humanities classes to majority low-income, minority adults. In this paper qualitative research methods are used to interview students, professors and an administrator at Clemente. Based upon qualitative research, supported by retention theory, three main reasons for attrition are identified: student academic self-esteem, diversity of student learners and challenges personal student challenges. Possible solutions are provided based upon the reasons identified

When Society Becomes the Criminal: An Exploration of Society’s Responsibilities to the Wrongfully Convicted

This thesis explores how society can and should compensate those who have been wrongfully convicted after they are exonerated and how we can prevent these mistakes from happening to others in the future. It begins by presenting research on the scope of the problem. Then it suggests possible reforms to the U.S. justice system that would minimize the rate of innocent convictions. Lastly, it takes both a philosophical and political look at what just compensation would entail as well as a variety of state compensation laws

Assessment of asthma control and asthma exacerbations in the epidemiology and natural history of asthma: outcomes and treatment regimens (TENOR) observational cohort

Patients with severe or difficult-to-treat asthma account for substantial asthma morbidity, mortality, and healthcare burden despite comprising only a small proportion of the total asthma population. TENOR, a multicenter, observational, prospective cohort study was initiated in 2001. It enrolled 4,756 adults, adolescents and children with severe or difficult-to-treat asthma who were followed semi-annually and annually for three years, enabling insight to be gained into this understudied population. A broad range of demographic, clinical, and patient self-reported assessments were completed during the follow-up period. Here, we present key findings from the TENOR registry in relation to asthma control and exacerbations, including the identification of specific subgroups found to be at particularly high-risk. Identification of the factors and subgroups associated with poor asthma control and increased risk of exacerbations can help physicians design individual asthma management, and improve asthma-related health outcomes for these patients

The Lubrication Ability of Ionic Liquids as Additives for Wind Turbine Gearboxes Oils

The amount of energy that can be gained from the wind is unlimited, unlike current energy sources such as fossil and coal. While there is an important push in the use of wind energy, gears and bearing components of the turbines often fail due to contact fatigue, causing costly repairs and downtime. The objective of this work is to investigate the potential tribological benefits of two phosphonium-based ionic liquids (ILs) as additives to a synthetic lubricant without additives and to a fully formulated and commercially available wind turbine oil. In this work, AISI 52100 steel disks were tested in a ball-on-flat reciprocating tribometer against AISI 440C steel balls. Surface finish also affects the tribological properties of gear surfaces. In order to understand the combined effect of using the ILs with surface finish, two surface finishes were also used in this study. Adding ILs to the commercial available or synthetic lubricant reduced the wear scar diameter for both surface finishes. This decrease was particularly important for trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl) amide, where a wear reduction of the steel disk around 20% and 23% is reached when 5 wt % of this IL is added to the commercially available lubricant and to the synthetic lubricant without additives, respectively

An Investigation of Pre-Service Social Studies Teachers' Beliefs about Global Education: Evidence from Personal Narratives of Learning and Teaching

This dissertation study explored the beliefs of three pre-service teachers about teaching global issues as well as the factors that influenced those beliefs and ultimately what and how they decided to teach. The literature reviewed implies that the goal of global education should be that students learn to view themselves as global citizens, meaning that they should understand their role and take responsibility and action with regards to the global issues they learn about. Data sources used to explore the teachers’ beliefs included a series of three semi-structured interviews, instructional planning artifacts, and participant reflection journals. The conceptual framework proposed that beliefs guide instruction, which proved to be evident in the instructional planning artifacts in each of the cases studied. The findings demonstrated that the participants’ beliefs were heavily influenced by prior experiences, their mentor, and the teacher education program. These influences resulted in the participants taking on different stances about the role of global education. The pre-service teachers in this study do not exhibit beliefs aligned with an active citizenship stance towards global education and, instead, the participants are oriented towards global awareness and global perspective-taking. The findings suggest a need for the development and use of a framework for teaching global issues that is aligned to an active citizenship approach towards global education