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Yes / The complexes [RuCp*(PP)Cl] (Cp* = C5Me5; [1], PP = dppm; [4], PP = Xantphos), [RuCp#(PP)Cl] (Cp# = C5Me4(CH2)5OH; [2], PP = dppm; [5], PP = Xantphos) and [RuCp*(dppm)(CH3CN)][SbF6] [3] were synthesized and evaluated in vitro as anticancer agents. Compounds 1–3 gave nanomolar IC50 values against normoxic A2780 and HT-29 cell lines, and were also tested against hypoxic HT-29 cells, maintaining their high activity. Complex 3 yielded an IC50 value of 0.55 ± 0.03 μM under a 0.1% O2 concentration.

L'étude a porté sur la conversion en presence de catalyseurs bimétaliques supportes de trois molécules modèles de polyols (érythritol, xylitol et sorbitol) en phase aqueuse à 150-240 ° C sous 30-120 bar de H2 pour obtenir sélectivement des produits linéaires C4, C5 et C6 désoxygénés qui sont des précurseurs de polymèrs. L'activité catalytique dépend fortement de la nature du support utilisé (TiO2 vs ZrO2) et la plus grande sélectivité pour les produits désoxygénés linéaires voulus C4, C5 et C6 à une conversion de 80% est de 71, 66 et 54%, respectivement, en présence de catalyseur mixte à base de rhodium et du rhenium à 200 ° C sous 80-120 bar. Les caractérisations des catalyseurs par chimisorption de CO, MET-EDX, TGA-MS et XPS suggèrent une distribution et une réductibilité différentes des espèces de Re sur les nanoparticules Rh supportées en fonction du support permettant d'expliquer ces différences / The aim of our research project reports a study of heterogeneously catalyzed conversion of three polyol model molecules (erythritol, xylitol, and sorbitol) in aqueous phase at 150-240 °C under 30-120 bar of H2 to obtain selectively linear deoxygenated C4, C5, and C6 products used as precursors for polymer applications. The activity was strongly dependent on the nature of the support (TiO2 vs ZrO2) and the highest selectivity to the desired linear deoxygenated C4, C5, and C6 products at 80% conversion reached 71, 66, and 54%, respectively, in the presence of Rh–ReOx bimetallic catalysts at 200°C under 80-120 bar. The characterizations of the catalysts by CO chemisorption, TEM-EDX, TGA-MS, and XPS suggest a different distribution and reducibility of Re species over the supported Rh nanoparticles depending on the support that can explain these differences

While research on peer feedback in L2 writing has proliferated over the past two decades, not much is known about how EFL writers, driven by their motives and situated within their social, cultural and historical contexts, participate in group peer feedback of L2 writing. To fill such an important void, the present study investigates six Chinese EFL university students’ participation in group peer feedback activities of L2 writing from a sociocultural and activity theory perspective. Based on sociocultural theory and activity theory in particular, the present study proposes a tentative group peer feedback activity system model and explores Chinese EFL writers’ motives for participating in group peer feedback, how their motives influence group interaction and text revisions, and how they employ mediating strategies to facilitate group interaction and realize their motives during group peer feedback activities. / The study adopts a case study approach with a multiple-case design and collects multiple sources of data including video recordings of peer feedback sessions, semi-structured interviews, stimulated recalls, and drafts of student texts. Six Chinese EFL university students were selected through purposive sampling to participate in the study. Data analyses indicate that EFL students’ group peer feedback activities are driven and defined by their motives and mediated by their social, cultural and historical contexts. The findings revealed four major types of student motives for group peer feedback activities in the writing classroom: (1) feedback-giving and the learning process; (2) feedback-receiving and the learning product; (3) fixing errors in writing; and (4) getting the job done, which were shaped by a myriad of individual and sociocultural factors such as students’ personal belief systems, their secondary education experiences and the exam-oriented learning culture and education system. The study also found that student motives for peer feedback have great influences on students’ stances for group peer feedback and the patterns of group interaction, as well as the text revisions. Driven by different motives, the students were involved in different peer feedback systems in which they took different stances for peer feed-back and interacted differently with their group members, even though some of them were working in the same group and of similar English proficiency level. The study also reveals four major types of mediating strategies in peer feedback activities of L2 writing: artefact-mediated, rule-mediated, community-mediated, and division of labour-mediated strategies. The six students made use of these mediating strategies at different levels to realize their motives in the peer feedback activities. / Informed by the peer feedback activity system and the major findings of the present study, a tentative model to conceptualize the effective peer feedback activity in the EFL writing classroom has been proposed, which serves as a tentative conceptual and pedagogical model for research and practice in peer feedback of L2 writing. This study contributes new knowledge to the field by relating students’ motives to other key elements in peer feedback such as mediating strategies, peer stances, group interaction and student revisions of L2 writing, yielding a deepened understanding of students’ participation in and engagement with peer feedback in EFL writing. / 儘管在二語寫作領域有大量研究關注同伴回饋，但鮮有研究者探討外語寫作學習者如何在其動機的驅使下和社會文化環境的影響下參與小組同伴回饋活動。鑒於此，本研究在社會文化理論和活動理論的基礎上，構建了外語寫作小組同伴回饋活動系統，並以該活動系統為概念框架探究六位中國外語寫作學習者的小組同伴回饋動機，分析其與小組交互和文本修改的關係。本研究還探討外語寫作學習者如何採取仲介策略輔助小組交互和實現回饋動機。 / 本研究採用多案例個案研究的範式，通過目的性抽樣原則，從中國大陸某大學選取六位英語寫作學習者作為被試，收集了多種形式的資料，包括同伴回饋錄影、半結構性訪談、刺激性回憶和寫作文本資料。資料分析顯示外語寫作學習者的小組同伴回饋活動由學生的動機驅使，並受到學生所處的社會文化環境影響。研究發現四種類型的同伴回饋動機：（1）回饋給予與學習過程型；（2）回饋接收與學習結果型；（3）修改文本錯誤型；和（4）完成任務型。這四類同伴回饋動機是在學習者個體因素（如學生的信念、中學學習經歷等）和社會文化因素（如考試取向的教育環境等）的交互影響下形成的。本研究還發現回饋動機對學習者的回饋立場、小組交互模式及其文本修改都會有一定的影響。在不同類型動機的驅使下，即使學習者來自同一小組或英語水準相當，他們也嵌套于不同的同伴回饋系統中，其回饋立場和交互模式也會有所不同。研究還揭示出學生在小組同伴回饋中採用四種仲介策略實現其回饋動機：人工製品仲介策略、規則仲介策略、社群仲介策略和任務分工仲介策略。 / Yu, Shulin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 255-275). / Abstracts also in Chinese. / Title from PDF title page (viewed on 21, December, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.

CsrA is a global post-transcriptional regulatory protein that has a great impact on many physiological pathways in a cell. It regulates central carbon metabolism, motility and biofilm formation as well as virulence, pathogenesis, quorum sensing and the oxidative stress response. However, CsrA is in turn also regulated by CsrB and CsrC sRNAs, among other factors. In this study, we explore its regulatory effect on three different genes/operons, cstA, glgCAP and flhDC. We performed beta-galactosidase assays on wild type (wt) and RNase P temperature sensitive (ts) cells to determine the dependence on RNaseP for the CsrA, CsrB and CsrC regulatory cascade on these three genes. Our results showed a clear decrease in cstA and glgCAP activity during CsrA activation, suggesting a regulatory cascade in which inhibition of RNase P leads to an inactivation of CsrB and CsrC. This in turn leads to an activation of CsrA and an inhibition of cstA and glgCAP. The effect on flhDC, however, was not as clear and needs further investigation.

Wire Electrical Discharge Machining (WEDM) is a nontraditional machining process used for machining intricate shapes in high strength and temperature resistive (HSTR) materials. WEDM provides high accuracy, repeatability, and a better surface finish; however the tradeoff is a very slow machining rate. Due to the slow machining rate in WEDM, machining tasks take many hours depending on the complexity of the job. Because of this, users of WEDM try to predict machining rate beforehand so that input parameter values can be pre-programmed to achieve automated machining. However, partial success with traditional methodologies such as thermal modeling, artificial neural networks, mathematical, statistical, and empirical models left this problem still open for further research and exploration of alternative methods. Also, earlier efforts in applying the decision tree rule induction algorithms for predicting the machining rate in WEDM had limitations such as use of coarse grained method of discretizing the target and exploration of only C4.5 as the learning algorithm. The goal of this dissertation was to address the limitations reported in literature in using decision tree rule induction algorithms for WEDM. In this study, the three decision tree inductive algorithms C5.0, CART and CHAID have been applied for predicting material removal rate when the target was discretized into varied number of classes (two, three, four, and five classes) by three discretization methods. There were a total of 36 distinct combinations when learning algorithms, discretization methods, and number of classes in the target are combined. All of these 36 models have been developed and evaluated based on the prediction accuracy. From this research, a total of 21 models found to be suitable for WEDM that have prediction accuracy ranging from 71.43% through 100%. The models indentified in the current study not only achieved better prediction accuracy compared to previous studies, but also allows the users to have much better control over WEDM than what was previously possible. Application of inductive learning and development of suitable predictive models for WEDM by incorporating varied number of classes in the target, different learning algorithms, and different discretization methods have been the major contribution of this research.

We estimate a multivariate unobserved components stochastic volatility model to explain the dynamics of a panel of six exchange rates against the US Dollar. The empirical model is based on the assumption that both countries' monetary policy strategies may be well described by Taylor rules with a time-varying inflation target, a time-varying natural rate of unemployment, and interest rate smoothing. The estimates closely track major movements along with important time series properties of real and nominal exchange rates across all currencies considered. The model generally outperforms a benchmark model that does not account for changes in trend inflation and trend unemployment. (authors' abstract) / Series: Department of Economics Working Paper Series

Antibodies have become indispensable tools in diagnostics, research and as therapeutics. There are several strategies to generate monoclonal antibodies (mAbs) in order to avoid the drawbacks of polyclonal antibodies (pAbs) for therapeutic use. Moreover, the growing interest in precision medicine requires a well-characterized target and antibody to predict the responsiveness of a treatment. This thesis describes the use of epitope information and display technologies to generate and characterize antibodies. In Paper I, we evaluated if the epitope information of a well-characterized pAb could be used to generate mAbs with retained binding characteristics. In Paper II, the epitope on the complement protein C5 towards Eculizumab was mapped with surface display, the results of which explained the non-responsiveness of Eculizumab treatment among a patient group due to a mutated C5 gene. With this in mind, we showed efficacy in treatment of the mutated C5 variants using a drug binding to another site on C5, suggesting that our approach can be used to guide treatment in precision medicine. In Paper III, a Gram-positive bacterial display platform was evaluated to complement existing platforms for selection of human scFv libraries. When combined with phage display, a thorough library screening and isolation of nano-molar binders was possible. In Paper IV, a solid phase method for directed mutagenesis was developed to generate functional affinity maturation libraries by simultaneous targeting of all six CDRs. The method was also used to create numerous individual mutants to map the paratope of the parent scFv. The paratope information was used to create directed libraries and deep sequencing of the affinity maturation libraries confirmed the viability of the combination approach. Taken together, precise epitope/paratope information together with display technologies have the potential to generate attractive therapeutic antibodies and direct treatment in precision medicine. / <p>QC 20170418</p>

Communities around the world are confronting unique challenges to sustain their local environment, culture and identity in the face of climate change. From B.C.’s coastal communities to Arctic gateway cities in the north, UBC Vancouver sociology professor Ralph Matthews is leading teams of researchers in the study of the sociological and cultural implications of climate change through two distinct projects: The Co-Management of Climate Change in Coastal British Columbia (C5) Project and The City of Whitehorse – Climate Change and Institutional Adaptive Capacity Project.

One of the most devastating effects of tetraplegia is the inability to grasp and manipulate everyday objects necessary to living an independent life. Currently surgery is widely accepted as the solution to improve hand functionality. However, surgery becomes difficult when the user has paralysed wrists as is the case with C5 tetraplegia. The aim of this research was to develop a solution which provided controlled wrist flexion and extension which, when combined with surgery, achieves a 'key pinch' grip. This particular grip is critically important for people with C5 tetraplegia as it is used for countless grasping activities, necessary on a day-to-day basis. A systematic design process was used to evolve the solution to provide controlled wrist flexion and extension. Concept brainstorming identified four alternative solutions which were evaluated to find the preferred concept. The chosen solution was called the Self Powered Wrist Extension Orthosis, more commonly referred to as the 'orthosis'. This concept contained a shoulder harness which provided both energy and control to the wrist harness, which in turn changed the wrist position. The orthosis was developed with the use of a mathematical model which theoretically predicted the functional performance by comparing the required force needed to move the wrist harness to the achievable force supplied by the user's shoulders. Using these parameters, the orthosis was optimized using the matlab Nelder-Mead algorithm which adjusted the wrist harness geometries to maximize the functional performance. A prototype was constructed and tested with the help of two participants who when combined, achieved an average of 18.5° of wrist rotation. The theoretical model however predicted an average range of motion of 28.4°. The discrepancy found between the theoretical and experimental result can be contributed to incorrect assumptions in the theoretical model. This included unaccounted friction and inaccurate modeling of the orthosis dynamics. The feedback from potential users of the orthosis was enthusiastic and encouraging especially towards the simplicity, usability and practicality of the design.