Terpene Syntheses Employing Aromatic Precursors

The thesis comprises two parts. In Part I, a review, complete to March, 1963, is given of all known aromatic diterpenes having an octahydrophenanthrene ring system and in particular of the compound totarolone. Aspects of their biogenesis and synthesis are discussed. An account is given of an investigation of a number of naphthalene derivatives which could function as precursors for a synthesis of totarolone. In an attempt to prepare 1,2,3,4-tetrahydro-5-isopropyl-2-keto-6-methoxy-l-methylnaphthalene, 2,6-dimethoxynaphthalene, 1-isonropyl-2-methoxy-naphthalene and l-isopropyl-2,6-dimethoxynaphbhalene were synthesised. 2,6-Dimethoxynaphthalene could be reduced to the 1,4-dihydro-derivative but attempts to methylate this product at the 1-position failed. l-Isopropyl-2-methoxynaphthalene underwent an abnormal nitration reaction giving an a-nitroketone with loss of the O-methyl group. 5-Bromo-6-hydroxytetralin was converted to 5-isopropyl-6-methoxytetralin which has now been converted, elsewhere to totarolone. Methyl 2-hydroxy-1-naphthoate was converted to l-isopropenyl-2-naphthol and 1-isopropyl-2-naphthol. The latter, however, proved to be much more readily available by direct alkylation of sodium 2-naphthoxide. The mechanism, of this process is discussed. l-Isopropyl-2-naphthol showed a remarkable propensity for oxygen absorption, being rapidly converted in air to 1,2-dihydro-1-h-ydropsroxy-l-isoprooyl- 2-keto-naphthalene. Since an autoxidation is possibly a key step in the biogenesis of totarol, this reaction was studied in some detail and comparison made of the reactivity of l-isopropyl-2-naphthol with that of 1-methyl-2-naphthol and 3-isopropyl-2-naphthol, the latter being prepared from 2-hydroxy-3-naphthoic acid. In Part II, the structures, biogenesis and published syntheses of all known iridoid monoterpenes are reviewed. An account is given of a reinvestigation of a synthetic approach to these substances from suitably substituted indanes. Condensation of para-cresol with ethyl acetoacetate gave 4,6-dimethyl-coumarin which was converted to 3-(2-methoxy-5-methylphenyl)butyric acid. Oyclisation of this with polyphosphoric acid gave a methoxyindanone which on Clemmensen reduction and demethylation gave 7-hydroxy-1,4-dimethylindane. This phenol was also obtained by rearrangement of the 3,4-dihydro-derivative of the above coumarin to a hydroxyindanone and reductive removal of the carbonyl group of the latter by the Clemmensen procedure. The degradation of this phenol to nepetalinic acid has been investigated. By a route similar to the first one above, 5,7-dihydroxy-1,4-bimethylindane has been prepared from 4-methylresorcinol and ethyl acetoacetate. It should be possible to convert this relatively simply to nepetalinic acid and research on this subject is continuing

A Systems Approach to Dissecting Immune Gene Regulatory Networks in the Modulation of Brain Function

Although the central nervous system was long perceived as the ivory tower without immune entities, there is growing evidence that the immune and nervous systems are intimated connected. These two systems have been shown to communicate both cellularly and molecularly under physiological and pathological conditions. Despite our increasing understanding of the interplay between these two systems, there are still numerous open questions. In this thesis, I address such unanswered questions related to: the role of microglia and their mechanism in contributing to pathologies in Rett syndrome; the beneficial effects of T-cell secreted cytokines in supporting social brain function; the evolutionary link of the interactions between the nervous and immune systems; the transcription regulation of a subset of microglia population in common neurodegenerative diseases. Collectively, the current thesis is focused on the joint frontier of bioinformatics and experimental work in neuroimmunology. A multifaceted approach, that includes transcriptomics, genomics and other biomolecular modules, was implemented to unearth signaling pathways and mechanisms underlying the presenting biological phenomena. The findings of this thesis can be summarized as follows: 1) MeCP2 acts as a master regulator in the transcriptional repression of inflammatory stimuli in macrophages; 2) T-cell secreted IFN-γ supports social brain function through an evolutionally conserved interaction between the immune and nervous systems; 3) The APOE-TREM2 pathway regulates the microglia phenotype switch in neurodegenerative diseases. Provided that recent technologies allow for readily manipulating the immune system, the findings presented herein may create new vistas for therapeutic interventions in various neurological disorders

Auto-evaluación previa a las prácticas de laboratorio químico: introducción al autoaprendizaje

In this work a strategy to improve learning outcomes of laboratory sessions of a Chemistry subject of the Bachelor's Degree in Rural and Agrifood Engineering is shown. In this experience the e-learning platform PoliformaT was used to propose timed pre-lab questionnaires to allow self-assessment of students before laboratory sessions, this allowed an increase in the preparation and the interest of the student on the performance of the laboratory session. The effectiveness of this strategy was established from the analysis of data collected during its application and also by means of an opinion call. It is noteworthy that these questionnaires have induced change of attitude among students, encouraging an active posture (and positive) towards the laboratory session.[ES] : En este trabajo se muestra una estrategia para mejorar los resultados de aprendizaje en las prácticas de laboratorio en una asignatura de Química del Grado en Ingeniería Agroalimentaria y del Medio Rural realizando cuestionarios previos temporizados usando la plataforma e-learning PoliformaT. De este modo, se ha permitido la auto-evaluación de los alumnos antes de realizar una sesión de prácticas, fomentando la preparación y el interés del alumno en su realización y consiguiendo un mayor aprovechamiento de los recursos. La eficacia de esta estrategia se ha establecido a partir del análisis de datos recogidos durante la aplicación y realizando un sondeo de opinión. La aplicación de estos cuestionarios ha permitido un cambio de actitud en los alumnos, fomentando una actitud activa (y positiva) hacia las prácticas y consiguiendo un mayor aprovechamiento de las mismasNoguera Murray, PS.; Tortajada Genaro, LA.; Atienza Boronat, MJ.; Herrero Villen, MA. (2011). Auto-evaluación previa a las prácticas de laboratorio químico: introducción al autoaprendizaje. Arbor. 187(3):267-272. doi:10.3989/arbor.2011.Extra-3n3156S2672721873Burewicz, A., & Miranowicz, N. (2006). Effectiveness of multimedia laboratory instruction. Chem. Educ. Res. Pract., 7(1), 1-12. doi:10.1039/b4rp90006eDalgarno, B., Bishop, A. G., Adlong, W., & Bedgood, D. R. (2009). Effectiveness of a Virtual Laboratory as a preparatory resource for Distance Education chemistry students. Computers & Education, 53(3), 853-865. doi:10.1016/j.compedu.2009.05.005Limniou, M., Papadopoulos, N., & Whitehead, C. (2009). Integration of simulation into pre-laboratory chemical course: Computer cluster versus WebCT. Computers & Education, 52(1), 45-52. doi:10.1016/j.compedu.2008.06.006Reid, N., & Shah, I. (2007). The role of laboratory work in university chemistry. Chem. Educ. Res. Pract., 8(2), 172-185. doi:10.1039/b5rp90026cRoffe, I. (2002). E‐learning: engagement, enhancement and execution. Quality Assurance in Education, 10(1), 40-50. doi:10.1108/09684880210416102Yang, Y.-F., & Tsai, C.-C. (2010). Conceptions of and approaches to learning through online peer assessment. Learning and Instruction, 20(1), 72-83. doi:10.1016/j.learninstruc.2009.01.00

Flatland

Flatland is a project of VCDE233 TYPOGRAPHY II and VCDI223 DESIGN AND PRE-PRESS PRODUCTION, both courses in the Design Studies diploma program at MacEwan University. Students were asked to translate an assigned section of the Victorian novella, Flatland: A Romance of Many Dimensions by Edwin A. Abbott (1884), into a two-page layout that treats the text in a way that is visually appealing, readable, and appropriate to the content. They were encouraged to challenge conventions by exploring alternative grids, objective and expressive type, and text and image relationships. VCDE233 Typography II (Constanza Pacher) and VCDI223 Design and Pre-Press Production (Jess Dupuis

Concurrent enrollment in lecture and laboratory enhances student performance and retention

Laboratories have been a cornerstone in teaching and learning across multiple scientific disciplines for more than 100 years. At the collegiate level, science laboratories and their corresponding lectures are often offered as separate courses, and students may not be required to concurrently enroll in both. In this study, we provide evidence that enrolling in an introductory laboratory concurrently with the corresponding lecture course enhances learning gains and retention in comparison to students who enroll in the lecture alone. We examined the impact of concurrent versus nonconcurrent enrollment on 9,438 students' withdrawal rates from and final grades in the general chemistry lecture at the University of Michigan at Ann Arbor using multiple linear and binary logistic regression analyses, respectively, at a significance level of 0.05. We found that concurrent enrollment in the lecture and laboratory positively impacts (1) the odds of retention in the lecture by 2.2 times on average and (2) final lecture grades by up to 0.19 grade points on a 4.0 scale for the lowest‐scoring students according to university‐level mathematics and chemistry placement exam scores. These data provide important results for consideration by curriculum advisors and course planners at universities that do not require concurrent enrollment in general chemistry as well as other science courses. In the face of current budget cuts that threaten to shorten or eliminate laboratory experiences altogether at multiple educational levels, this study demonstrates the value of laboratories in promoting science learning and retention. © 2012 Wiley Periodicals, Inc. J Res Sci Teach 49: 659–682, 2012Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91231/1/21016_ftp.pd

The Effect of a Paired Lab on Course Completion and Grades in Nonmajors Introductory Biology

This paper explores the effect of a paired lab course on students’ course outcomes in nonmajors introductory biology at the University of Alaska Anchorage. We compare course completion and final grades for 10,793 students (3736 who simultaneously enrolled in the lab and 7057 who did not). Unconditionally, students who self-select into the lab are more likely to complete the course and to earn a higher grade than students who do not. However, when we condition on observable course, academic, and demographic characteristics, we find much of this difference in student performance outcomes is attributable to selection bias, rather than an effect of the lab itself. The data and discussion challenge the misconception that labs serve as recitations for lecture content, noting that the learning objectives of science labs should be more clearly articulated and assessed independent of lecture course outcomes. This paper explores the effect of a paired lab course on students’ course outcomes in introductory biology for nonmajors at the University of Alaska Anchorage (UAA), a large, open-enrollment, 4-year university. We compare outcomes for 10,793 students, 3736 who simultaneously enrolled in the lab and 7057 who did not, and analyze the degree to which they select into the lab on observable characteristics to explore the following research questions: 1. Are students who take a paired lab more likely to complete the lecture component (i.e., receive a final grade as opposed to withdrawing or receiving an Incomplete)? 2. Are students who take a paired lab more likely to receive a higher grade in the lecture component? 3. Does the laboratory experience differently affect course outcomes for students in specific demographic subgroups (e.g., gender, race, high school urbanicity, age, prior academic performance, and socioeconomic status)

Application of aerodynamic model structure determination to UAV data

This paper concerns aircraft system identification and, in particular, the process of aerodynamic model structure determination. Its application to experimental data from unmanned aerial vehicles (UAVs) is also described. The procedure can be particularly useful for determining an aerodynamic model for aircraft with unconventional airframe configurations, which some unmanned aircraft tend to have. Two model structure determination techniques are outlined. The first is the well-established stepwise regression method, while the second is an adaptation of an existing frequency response approach which instead utilises maximum likelihood estimation. Example applications of the methods are presented for two data sources. The first is a set of UAV flight test data and the second is data recorded from dynamic wind tunnel tests on a UAV configuration. For both examples, the model structures determined using stepwise regression and maximum likelihood analysis matched one another, suggesting that the maximum likelihood approach and the chosen thresholds for its statistical metrics were reliable for the data being analysed

Formulation and System Identification of the Equations of Motion for a Dynamic Wind Tunnel Facility.

This document describes the equations of motion of an aircraft model tested in Cranfield’s 4 degreeof- freedom (DoF) wind tunnel facility. In previous research, the equations have been derived assuming that the model’s centre of gravity (cg) is coincident with the gimbal mechanism about which the model rotates on the rig. However, in this report a general approach is taken with the cg assumed to be located away from the gimbal. The equations are developed from first principles and reduced to a linearised form where motion can be represented as small perturbations about trim. The equations are also decoupled into longitudinal and lateral/direction expressions and converted into state space form. It had been found in practice that models tested in the facility are very responsive in heave and can only be operated open-loop if movement is restricted to purely rotational motion. Therefore, the equations for this 3DoF case are also developed. Having obtained theoretical expressions, a series of wind tunnel tests were conducted on a 1/12 scale BAe Hawk model in order to establish if the theoretical relations were valid in practice. The particular technique used in testing the model was dynamic simulation and the analysis of the experimental data was performed using system identification. An established model structure determination procedure is used to determine which stability and control derivatives should be included in the equations of motion. Frequency domain, equation error parameter estimation is then employed to obtain numerical values for the stability and control derivatives. For both the longitudinal and lateral/directional examples described, the final model structure obtained from experiment matches that derived from theory. Derivatives values obtained from parameter estimation and empirical analysis are also in good agreement