Coordination is important in groupware because it helps users collaborate efficiently. However, groupware systems in which activities occur at a faster pace need faster coordination in order to keep up with the speed of the activity. Faster coordination is especially needed when actions are dependent on one another (i.e., they are tightly-coupled) and when each user can see and interact with other users actions as they occur (i.e., real time). There is little information available about this type of fast coordination (also named high-speed coordination or HSC) in groupware. In this thesis, I addressed this problem by providing a body of principles and information about high-speed coordination. This solution was achieved by creating a groupware game called RTChess and then conducting an exploratory evaluation in which high-speed coordination was investigated. The results of this evaluation show that there were small amounts of high-speed coordination in the game and that high-speed coordination was difficult to achieve. In addition, HSC was affected by five main characteristics of the groupware environment: user experience, level of awareness of the partners interactions, communication between partners, number of dependencies that affect the users interactions, and pace of activities in the system.

Les dianions géminés stabilisés par des phosphores hypervalents ont récemment éveillé un vif intérêt en tant que précurseurs carbéniques pour les métaux d0 et les lanthanides ; Cependant, les interactions entre les éléments du groupe principal, comme le carbone, et ces métaux sont réputées essentiellement ionique et peu directionnelles, tandis que les liaisons entre le carbone et le métal dans un complexe carbénique classique sont usuellement décrites comme étant directionnelle et partiellement covalente. Le travail effectué au cours de cette thèse vise à synthétiser de nouveaux complexes de métaux du groupe 3, stabilisés par un dianion géminé bis(diphénylthiophosphinoyl)méthanediure, dans le but d'en étudier la réactivité et d'en modéliser la structure électronique, pour une meilleure compréhension de l'interaction multiple métal-ligand. Ces études ont été menées sur le scandium, puis partiellement étendues aux autres éléments du groupe 3 : yttrium et lutétium. Il ressort de cette étude que ces interactions sont directionnelles, de symétrie σ et π, mais qu'elles restent en compétition avec la stabilisation présente ab initio au sein du ligand dianionique libre. Cette stabilisation permet une adaptation de l'interaction carbone-métal en fonction des autres ligands présents dans la sphère de coordination : lorsqu'ils sont à caractère ionique et donneur fort, l'interaction carbone-métal prend un caractère plus ionique et l'interaction de symétrie π peut être rompue. La réactivité reste proche de celle d'un carbène de type Schrock. Des réactions indésirables menant à la détérioration du ligand ont également été observées ; un ligand plus résistant, porteur de fonctions phosphine-borane et oxyde de phosphine a été proposé. De nouvelles perspectives quant à la réactivité de ces espèces ont été également explorées : transmétallation permettant d'accéder à de nouveaux complexes aux propriétés magnétiques intéressantes, réaction de couplage des alcynes notamment.

A series of 1,2,3-dithiazolyl radicals have been prepared as spin-bearing radical ligands for coordination to paramagnetic transition metal and lanthanide ions to afford both interesting magnetic and potential conductive properties. The novel syntheses and full characterization of the ligands are described with the electronic properties investigated by both solution & solid-state EPR and cyclic voltammetry. The ligand structures are characterized by X-ray crystallography and the magnetic properties investigated. The ligands described herein represent the first reported 1,2,3-dithiazolyl radical ligands to coordinate to paramagnetic transition metal or lanthanide ion(s). The 1,2,3-dithiazoyl ligands described have been used to prepare a number of metal complexes and the structures have been fully characterized by X-ray crystallography. A diverse range of complexes including monomers, trimers and polymers have been synthesized and characterized. The solid-state and solution magnetic properties of the metal complexes have been investigated using a range of appropriate instrumental techniques, and are reported. The chelating properties of the 1,2,3-dithiazolyl ligands described are via an unprecedented motif. A para-naphthoquinone backbone is utilized with the fused 1,2,3dithiazolyl heterocyclic ring. The coordination geometry between the nitrogen atom and the quinone oxygen(s) allows for the variety of complexes reported, including the design objective of a polymeric paramagnetic coordination complex. A series of 1,2,5-thiadiazolyl radical anions have been prepared as spin-bearing radical ligands for the coordination to paramagnetic transition metal and lanthanide ions to enable both interesting magnetic and conductive properties. The syntheses and full characterizations are described with the electronic properties investigated by solution EPR and cyclic voltammetry. The ligand structures are characterized by X-ray crystallography and both the magnetic properties and conductivity (including Extended Hückel Theory calculations) are investigated and reported. A series of novel fluorinated 1,2,5-thiadiazole closed shell neutral ligands have been prepared and characterized. The radical anion is studied in situ by EPR. All materials generated in the synthesis were sent to the National Cancer Institute (USA) for collaboration involving clinical cancer inhibition studies and the results are reported.

Ce travail de thèse traite de l'étude de la coordination de ligand phosphorés comportant une double liaison P=C sur des métaux riches, notamment le Ni(0) et le Pt(0). La coordination donne lieu à une isomérisation des fonctions phosphaalcènes en benzophospholane par insertion du phosphore dans une liaison C−H du supermésityle lié au phosphore. Un mécanisme réactionnel a été proposé. Ce mécanisme, appuyé par des calculs théorique, rationalise les observations expérimentales (notamment les intermédiaires observés). Une autre partie du travail s'intéresse à la coordination de ligand de type phosphaalcène à polarité inversée par la présence d'un ou plusieurs atomes d'azote en alpha du carbone de la liaison P=C. Leur capacité a donner deux paires libres a été étudiée ainsi que leur éventuelle application comme précurseurs de phosphinidènes.

This thesis details the synthesis and coordination chemistry of twenty-five nitrogencontaining heterocyclic ligands, nineteen of which were previously unreported compounds. These ligands were designed for use as synthons for the formation of molecular cages, so contain multiple coordination sites capable of bridging multiple metal atoms. The majority of molecular cages in the literature are formed by rigid bridging ligands, whereas the ligands studied in this research incorporate a higher level of flexibility, thereby lessening the degree of control over the self-assembly process and increasing the number of possible structures that can be formed upon reaction of these ligands with meal salts. Three of the new ligands synthesised were two-armed bridging ligands, which were reacted with a wide variety of metal salts to investigate what self-assembly products were formed. The complexes characterised include a M₃L₃ cyclic trimer, a range of coordination polymers of varying dimensionality, a range of dimeric products and a series of M₄L₆ cage-like molecular squares. However, the majority of ligands studied were three-armed, potentially tripodal compounds, which were envisaged as potential components of M₃L₂ or M₆L₄ molecular cages. The products of self-assembly of these ligands with various metals salts were shown to include a variety of discrete tri- and tetranuclear complexes, a range of coordination polymers of varying dimensionality and interpenetration, and a complex M₆L₄ assembly that appears to be a collapsed coordination cage. Unfortunately some of the ligands synthesised were shown to decompose in the presence of various metal salts, a phenomenon already identified in the literature. Analogues of these decomposition products were synthesised deliberately to identify the potential of a known tridentate ligand as a metallosupramolecular synthon. ¹H NMR spectroscopy, mass spectrometry, elemental analysis, thermogravimetric analysis and X-ray crystallography were used to study the compounds synthesised. The crystal structures of five ligands and fifty-one complexes are discussed.

Background: For children with developmental coordination disorder (DCD), the acquisition and performance of everyday visual-motor activities such as buttoning, shoe tying, cutting with scissors or writing, presents a major challenge. Regardless of the activity considered, children with DCD are typically slower and less accurate than their peers. Given the well-acknowledged difficulties of children with DCD, it is surprising to find very few research studies systematically exploring visual-motor skill acquisition and performance in children with DCD. Objective: The overall objective of this study was to systematically describe visual-motor skill acquisition and task performance in children with DCD. Methods: Twenty-four children (8 years 11 months to 12 years 11 months) were recruited for this study; 12 children with DCD, 12 children developing typically with regards to their motor skills. A computer-based aiming task completed with three different cursor controls of increasing levels of difficulty (mouse, joystick, novel controller) was designed for this study. Mixed-effect modelling and visual graph analyses were performed to describe the influence of motor ability and task difficulty on visual-motor skill acquisition and task performance. Results: Motor ability modulated the impact of task difficulty on visual-motor skill acquisition and task performance. Children with DCD were as fast and as accurate as their peers in their initial performance of the simple, well-learned task (mouse). However, they were slower and less accurate when performing the complex and novel visual-motor task. Over repeated trials, the visual-motor task performance of children with DCD improved on all tasks, even for the simple. With regard to the complex, novel task, once children with DCD understood the features of the task, their performance also improved and approached that of their peers. Conclusion: While children with DCD can generally be characterized as less accurate and slower than their peers, this characterization needs to be specified and qualified; it is probably best not applied to a well-learned task.

Coordination is a vital component in health care provision and teamwork. The need for better coordination is particularly prominent in outpatient setting where patients assume the primary responsibility to follow-up on their own health care, especially when treatment is complex and lengthy in duration. Relational coordination represents a type of informal coordination process reinforced by communication and supportive relationships. This concept has been associated with enhanced interprofessional team performance, including patient care outcomes. This study aimed to examine the theoretical underpinnings of relational coordination in the outpatient setting using social capital theory. It was hypothesized that social capital, resources embedded within network of relationships, would predict relational coordination. Additionally, social capital was hypothesized to be predicted by team tenure; and relational coordination was hypothesized to be predicted by formal coordination mechanisms. A non-experimental, cross-sectional survey design was used to examine the relationship between social capital and relational coordination. Participants (N=342) were physicians and nurses recruited from outpatient clinics in two University affiliated hospitals. Study surveys were sent to 501 nurses and 187 physicians with follow-up reminders sent at three, five and seven weeks after the initial distribution of surveys. The overall response rate was 49.71%. Study variables were measured using previously validated instruments with acceptable levels of reliability and validity. Structural equation modeling (SEM) was used for hypothesis testing. Final analysis revealed good fit of data to the hypothesized model (Chi-square=383.38, df=177, p<0.001; CFI=0.966; RMSEA=0.060; SRMR=0.0316). SEM revealed that social capital predicted both factors of relational coordination [communication (β=0.70, p<0.001); supportive relationship (β=0.81, p<0.001)], and team tenure predicted social capital (β=0.13, p<0.05). In addition, the association between team tenure and relational coordination (β=0.09, p<0.05) was found to be partially mediated by social capital. Findings of this study suggested that characteristics within relational ties are predictive of informal coordination. Administrators may facilitate teamwork through team building initiatives that foster these relational qualities, such as trust and shared language. Future research can further investigate the association between social capital and relational coordination in other health care settings, as well, in larger teams involving health care professionals in addition to physicians and nurses.

This thesis details the synthesis and coordination chemistry of twenty-five nitrogencontaining heterocyclic ligands, nineteen of which were previously unreported compounds. These ligands were designed for use as synthons for the formation of molecular cages, so contain multiple coordination sites capable of bridging multiple metal atoms. The majority of molecular cages in the literature are formed by rigid bridging ligands, whereas the ligands studied in this research incorporate a higher level of flexibility, thereby lessening the degree of control over the self-assembly process and increasing the number of possible structures that can be formed upon reaction of these ligands with meal salts. Three of the new ligands synthesised were two-armed bridging ligands, which were reacted with a wide variety of metal salts to investigate what self-assembly products were formed. The complexes characterised include a M₃L₃ cyclic trimer, a range of coordination polymers of varying dimensionality, a range of dimeric products and a series of M₄L₆ cage-like molecular squares. However, the majority of ligands studied were three-armed, potentially tripodal compounds, which were envisaged as potential components of M₃L₂ or M₆L₄ molecular cages. The products of self-assembly of these ligands with various metals salts were shown to include a variety of discrete tri- and tetranuclear complexes, a range of coordination polymers of varying dimensionality and interpenetration, and a complex M₆L₄ assembly that appears to be a collapsed coordination cage. Unfortunately some of the ligands synthesised were shown to decompose in the presence of various metal salts, a phenomenon already identified in the literature. Analogues of these decomposition products were synthesised deliberately to identify the potential of a known tridentate ligand as a metallosupramolecular synthon. ¹H NMR spectroscopy, mass spectrometry, elemental analysis, thermogravimetric analysis and X-ray crystallography were used to study the compounds synthesised. The crystal structures of five ligands and fifty-one complexes are discussed.

Thesis (MFA)--Rochester Institute of Technology, 1989. / Includes bibliographical references (leaf 22).

Thesis (M.S.)--Rochester Institute of Technology, 1993. / Typescript. Pamphlets, etc. are bound together with the text.