The vision of K-12 standards-based mathematics reform embraces a greater emphasis on students’ ability to communicate their understandings of mathematics by utilizing adaptive reasoning (i.e., reflection, explanation, and justification of thinking) through mathematics discourse. However, recent studies suggest that many students lack the socio-cognitive capacity needed to succeed in learner-centered, discussion-intensive mathematics classrooms. A multiple case study design was used to examine the nature of participation in mathematics discourse among two low- and two high-performing sixth grade female students while solving rational number tasks in a standards-based classroom. Data collected through classroom observations, student interviews, and student work samples were analyzed via a multiple-cycle coding process that yielded several important within-case and cross-case findings. Within-case analyses revealed that (a) students’ access to participation was mediated by the degree of space they were afforded and how they attempted to utilize that space, as well as the meaning they were able to construct through providing and listening to explanations; and (b) participation was greatly influenced by peer interactional tendencies that either promoted or impeded productive contributions, as well as teacher interactions that helped to offset some of the problems related to unequal access to participation. Cross-case findings suggested that (a) students’ willingness to contribute to task discussions was related to their goal orientations as well as the degree of social risk perceived with providing incorrect solutions before their peers; and (b) differences between the kinds of peer and teacher interactions that low- and high-performers engaged in were directly related to the types of challenges they faced during discussion of these tasks. An important implication of this study’s findings is that the provision of space and meaning for students to participate equitably in rich mathematics discourse depends greatly on teacher interaction, especially in small-group instructional settings where unequal peer status often leads to unequal peer interactions. Research and practice should continue to focus on addressing ways in which students can learn how to help provide adequate space and meaning in small-group mathematics discussion contexts so that all students involved are allowed access to an optimally rich learning experience.

Inhibition of angiogenesis is an effective and low toxic therapeutic avenue for the treatment of cancer patients in addition to traditional interventions. Majority of current available angiogenesis inhibitors for cancer therapies are growth factor inhibitors and small molecule tyrosine kinase inhibitors. A number of endogenous proteins and/or proteolytic fragments of extracellular matrix proteins are shown to have the activity of inhibition of angiogenesis by directly targeting endothelial cells. Structural analyses have indicated that a common structure of anti-parallel β-sheet with a highly positively charged surface presents in many of those inhibitors. This common structural feature is critical for the maintenance of their anti-angiogenic function. With this structural information, we have designed and developed a new class of anti-angiogenic proteins by integrating the short anti-parallel β-sheet forming sequences of endogenous anti-angiogenic proteins into a stable host protein, the extracellular domain-1 of cluster of differentiation 2 molecule (CD2D1). 1D 1H NMR spectra analyses indicated that the designed anti-angiogenic protein (ref to as ProAgio) folded as a β-sheet structure similar to that of the parental protein, CD2D1. ProAgio inhibited the growth of human umbilical vein cells (HUVECs) without affecting the growth of epithelial cells, suggesting a specific effect to endothelial cells. ProAgio effectively reduced endothelial tubules formed by the co-culture of HUVECs and PC3 cells on matrix gel in vitro. The designed anti-angiogenic protein was further site-specifically PEGylated in order to improve PK/PD properties and reduce immunogenicity. Examinations with PC3 xenografts showed that both ProAgio and the PEGylated ProAgio dramatically inhibited tumor growth. Immunofluorescence staining analyses of the endothelial marker CD31 indicated dramatic decreases in tumor vessels in lengths and branching points. Histological and immunofluorescence staining analyses of tissue slices of major organs indicated that there were no pathological damages to the tissue structure or disruption of normal vessels associated with the treatment of our designed anti-angiogenic agent. Overall, our studies developed a novel anti-angiogenesis agent that may have great clinical potentials. Our concept of protein design can be extended to the development of other novel protein drugs.

Small signal stability has always been an important concern for analog designers. Recent advances such as the Loop Finder algorithm allows designers to detect and identify local, potentially unstable return loops without the need to identify and add breakpoints. However, this method suffers from extremely high time and memory complexity and thus cannot be scaled to very large analog circuits. In this research work, we first take an in-depth look at the loop finder algorithm so as to identify certain key enhancements that can be made to overcome these shortcomings. We next propose pole discovery and impedance computation methods that address these shortcomings by exploring only a certain region of interest in the s-plane. The reduced time and memory complexity obtained via the new methodology allows us to extend automatic stability checking to much larger circuits than was previously possible.

This thesis explores and implements techniques for frequency domain modelling and time domain simulation of overhead transmission lines. The popular Vector Fitting algorithm is employed to approximate the frequency domain model using rational functions, and the recursive convolution technique is applied to the rational approximation to generate a time domain form. The frequency domain model is translated into the time domain using delay extraction, modal decomposition, passivity enforcement, and rational approximation. Several approaches to each of these procedures are investigated. The thesis also discusses several choices for the integration method used within the recursive convolution procedure. In order to make the transmission line modeller and simulator easy to use, a Java-based library and partial graphical interface were developed. Specifically, the goal was to develop a platform-independent program that can run either stand-alone or as an applet inside a web page. / October 2005

It might seem obvious that public opinions should be included in the planning process. However, it is not clear to what extent. Statutory forms of public participation attract little interest since many people feel that it is hard to make a difference. The purpose of this study was to engage those that normally do not get to speak their mind in the planning process. In this study, two methods for conducting “on-street surveys” were investigated. The place for the “on-street surveys” was Centralplan in Gävle. The two methods had different approaches. The “Stationary” method was a structured interview of pedestrians who had just crossed Centralplan. The “Follower” method was a structured interview that took place as the administrator and the participant crossed Centralplan in tandem. A total of 40 “Stationary” and 22 “Follower” interviews were conducted. The majority of the participants responded positively on making themselves heard within the planning process, indicating that they have important views to share. The methods used in this study can serve as an icebreaker for communication between planners and the public. / Det kan kännas självklart att allmänhetens åsikter ska vägas in i planeringsprocessen men i vilken utsträckning det ska ske är oklart. Lagstadgade former av medborgardeltagande väcker svalt intresse eftersom många upplever det som svårt att påverka. Syftet med den här studien var att engagera de människor som normalt inte kommer till tals i planeringsprocessen. I studien undersöktes två olika metoder för att genomföra gatuundersökningar, så kallade ”on-street surveys”. Platsen för genomförandet av gatuundersökningarna var Centralplan i Gävle. De två metoderna hade olika tillvägagångssätt. Metod ”Stationär” var en form av stillastående strukturerad intervju som utövades på platsen. Administratören frågade ut personer som alldeles precis hade förflyttat sig genom gaturummet. Metod ”Följeslagare” var en form av rörlig strukturerad intervju som utövades på platsen men där administratören slog följe med personen och ställde frågorna under tiden de passerade genom gaturummet. Totalt 62 personer medverkade i studien, varav 40 för metod ”Stationär” och 22 för metod ”Följeslagare”. Resultaten visade att allmänheten hade viktiga synpunkter att dela med sig av, till exempel om attityder och åsikter. Majoriteten av de medverkande ställde sig positiva till att få sin röst hörd inom planeringsprocessen. Metoderna som användes i studien skulle kunna fungera som dörröppnare för dialog mellan planerare och allmänheten.

The main topic of this thesis is the development of computational search methods that are useful in drug design applications. The emphasis is on exhaustiveness of the search method such that it can guarantee a certain level of geometric accuracy. In particular, the following two problems are addressed: (i) Prediction of binding mode of a drug molecule to a receptor and (ii) prediction of crystal structures of drug molecules. Predicting the binding mode(s) of a drug molecule to a target receptor is pivotal in structure-based rational drug design. In contrast to most approaches to solve this problem, the idea in this work is to analyze the search problem from a computational perspective. By building on top of an existing docking tool, new methods are proposed and relevant computational results are proven. These methods and results are applicable for other place-and-join frameworks as well. A fast approximation scheme for the docking of rigid fragments is described that guarantees certain geometric approximation factors. It is also demonstrated that this can be translated into an energy approximation for simple scoring functions. A polynomial time algorithm is developed for the matching phase of the docked rigid fragments. It is demonstrated that the generic matching problem is NP-hard. At the same time the optimality of the proposed algorithm is proven under certain scoring function conditions. The matching results are also applicable for some of the fragment-based de novo design methods. On the practical side, the proposed method is tested on 829 complexes from the PDB. The results show that the closest predicted pose to the native structure has the average RMS deviation of 1.06 °A. The prediction of crystal structures of small organic molecules has significantly improved over the last two decades. Most of the new developments, since the first blind test held in 1999, have occurred in the lattice energy estimation subproblem. In this work, a new efficient systematic search method that avoids random moves is proposed. It systematically searches through the space of possible crystal structures and conducts search space cuts based on statistics collected from the structural databases. It is demonstrated that the fast search method for rigid molecules can be extended to include flexible molecules as well. Also, the results of some prediction experiments are provided showing that in most cases the systematic search generates a structure with less than 1.0°A RMSD from the experimental crystal structure. The scoring function that has been developed for these experiments is described briefly. It is also demonstrated that with a more accurate lattice energy estimation function, better results can be achieved with the proposed robust search method.

This thesis seeks to examine why the Lavalas elite faction and its oppositions have failed to make and implement mutual agreements, to resolve regime crises and to create an environment conducive to democratic norms. The study derives explanations stemming from three alternative models: modernization, rational choice and misperception. Three periods of consensus-building attempt between the Lavalas elite and its oppositions (1991-1995: Consensus-Building attempt I; 1996-2000: Consensus-Building attempt II; 2000-2004: Consensus-Building attempt III) are considered. By using interpreted models a la Graham Allison, the thesis applies the criteria produced by each model to help interpret the failure of consensus-building in these three historical periods. The thesis' conclusion then assesses the models' strengths and weaknesses, prompting interesting questions for further research in the near future.

No description available.

BACKGROUND: When it comes to corporate decision making, the traditional rational model suggests that deliberative analysis yields good results. Thus, when contemplating strategic moves, executives are “required” to conduct deliberative analyses. As today’s business environment is becoming increasingly complex and fast-paced, however, executives often face the dilemma of having to make carefully considered strategic decisions on the one hand and not having enough time on the other hand. Intuition offers an efficient solution in this situation. PURPOSE: The purpose of this study is to investigate how corporate executives employ both rationality and intuition in making strategic decisions under uncertain, complex and time-pressured circumstances. RESEARCH METHOD: We conducted three face-to-face interviews with executives from three companies in Sweden. Each interview lasted around one hour.    RESULTS: Drawing on previous psychological and managerial research, we argue that rationality and intuition are better viewed as being complementary rather than separate. Findings from the study suggest that intuition could serve as an effective and efficient means for managers to make strategic decisions; and that intuition indeed plays a role in strategic decision making under complex, uncertain and time limited contexts.

The main topic of this thesis is the development of computational search methods that are useful in drug design applications. The emphasis is on exhaustiveness of the search method such that it can guarantee a certain level of geometric accuracy. In particular, the following two problems are addressed: (i) Prediction of binding mode of a drug molecule to a receptor and (ii) prediction of crystal structures of drug molecules. Predicting the binding mode(s) of a drug molecule to a target receptor is pivotal in structure-based rational drug design. In contrast to most approaches to solve this problem, the idea in this work is to analyze the search problem from a computational perspective. By building on top of an existing docking tool, new methods are proposed and relevant computational results are proven. These methods and results are applicable for other place-and-join frameworks as well. A fast approximation scheme for the docking of rigid fragments is described that guarantees certain geometric approximation factors. It is also demonstrated that this can be translated into an energy approximation for simple scoring functions. A polynomial time algorithm is developed for the matching phase of the docked rigid fragments. It is demonstrated that the generic matching problem is NP-hard. At the same time the optimality of the proposed algorithm is proven under certain scoring function conditions. The matching results are also applicable for some of the fragment-based de novo design methods. On the practical side, the proposed method is tested on 829 complexes from the PDB. The results show that the closest predicted pose to the native structure has the average RMS deviation of 1.06 °A. The prediction of crystal structures of small organic molecules has significantly improved over the last two decades. Most of the new developments, since the first blind test held in 1999, have occurred in the lattice energy estimation subproblem. In this work, a new efficient systematic search method that avoids random moves is proposed. It systematically searches through the space of possible crystal structures and conducts search space cuts based on statistics collected from the structural databases. It is demonstrated that the fast search method for rigid molecules can be extended to include flexible molecules as well. Also, the results of some prediction experiments are provided showing that in most cases the systematic search generates a structure with less than 1.0°A RMSD from the experimental crystal structure. The scoring function that has been developed for these experiments is described briefly. It is also demonstrated that with a more accurate lattice energy estimation function, better results can be achieved with the proposed robust search method.