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Jessica Lo

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Research paper thumbnail of The design and evaluation of multi-finger mouse emulation techniques

We explore the use of multi-finger input to emulate full mouse functionality, such as the trackin... more We explore the use of multi-finger input to emulate full mouse functionality, such as the tracking state, three buttons, and chording. We first present the design space for such techniques, which serves as a guide for the systematic investigation of possible solutions. We then perform a series of pilot studies to come up with recommendations for the various aspects of the design space. These pilot studies allow us to arrive at a recommended technique, the SDMouse. In a formal study, the SDMouse was shown to significantly improve performance in comparison to previously developed mouse emulation techniques.

Research paper thumbnail of Higher order organization of human placental aromatase

Steroids, 2011

Aromatase (CYP19A1) is an integral membrane enzyme that catalyzes the removal of the 19methyl gro... more Aromatase (CYP19A1) is an integral membrane enzyme that catalyzes the removal of the 19methyl group and aromatization of the A-ring of androgens. All human estrogens are synthesized from their androgenic precursors by this unique cytochrome P450. The crystal structure of active aromatase purified from human placenta has recently been determined in complex with its natural substrate androstenedione in the high-spin ferric state of heme. Hydrogen bond forming interactions and tight packing hydrophobic side chains closely complement puckering of the steroid backbone, thereby providing the molecular basis for the androgenic specificity of aromatase. In the crystal, aromatase molecules are linked by a head-to-tail intermolecular interaction via a surface loop between helix D and helix E of one aromatase molecule that penetrates the heme-proximal cavity of the neighboring, crystallographically-related molecule, thus forming in tandem a polymeric aromatase chain. This intermolecular interaction is similar to the aromatase-Cytochrome P450 reductase coupling and is driven by electrostatics between the negative potential surface of the D-E loop region and the positively charged heme-proximal cavity. This loop-to-proximal site link in aromatase is rather unique -there are only a few of examples of somewhat similar intermolecular interactions in the entire P450 structure database. Furthermore, the amino acids involved in the intermolecular contact appear to be specific for aromatase. Higher order organization of aromatase monomers may have implications in lipid integration and catalysis.

Research paper thumbnail of Loss of Cul1 results in early embryonic lethality and dysregulation of cyclin E

Nature Genetics, 1999

The sequential timing of cell-cycle transitions is primarily governed by the availability and act... more The sequential timing of cell-cycle transitions is primarily governed by the availability and activity of key cell-cycle proteins. Recent studies in yeast have identified a class of ubiquitin ligases (E3 enzymes) called SCF complexes, which regulate the abundance of proteins that promote and inhibit cell-cycle progression at the G1-S phase transition. SCF complexes consist of three invariable components, Skp1, Cul-1 (Cdc53 in yeast) and Rbx1, and a variable F-box protein that recruits a specific cellular protein to the ubquitin pathway for degradation. To study the role of Cul-1 in mammalian development and cell-cycle regulation, we generated mice deficient for Cul1 and analysed null embryos and heterozygous cell lines. We show that Cul1 is required for early mouse development and that Cul1 mutants fail to regulate the abundance of the G1 cyclin, cyclin E (encoded by Ccne), during embryogenesis.

Research paper thumbnail of and dysregulation of cyclin E

Research paper thumbnail of How meaningful are data from Likert scales? An evaluation of how ratings are made and the role of the response shift in the socially disadvantaged

Journal of Health Psychology, 2012

Likert scales relating to quality of life were completed by the homeless (N = 75); first year stu... more Likert scales relating to quality of life were completed by the homeless (N = 75); first year students (N = 301) and a town population (N = 72). Participants also completed free text questions. The scale and free text data were often contradictory and the results highlighted three processes to account for these disparities: i) frame of reference: current salient issues influenced how questions were interpreted; ii) within-subject comparisons: ratings were based on expectations given past experiences; iii) time frame: those with more stable circumstances showed habituation to their level of deprivation. Likert scale data should be understood within the context of how ratings are made.

Research paper thumbnail of Homework network exam questions

Research paper thumbnail of The design and evaluation of multi-finger mouse emulation techniques

We explore the use of multi-finger input to emulate full mouse functionality, such as the trackin... more We explore the use of multi-finger input to emulate full mouse functionality, such as the tracking state, three buttons, and chording. We first present the design space for such techniques, which serves as a guide for the systematic investigation of possible solutions. We then perform a series of pilot studies to come up with recommendations for the various aspects of the design space. These pilot studies allow us to arrive at a recommended technique, the SDMouse. In a formal study, the SDMouse was shown to significantly improve performance in comparison to previously developed mouse emulation techniques.

Research paper thumbnail of Higher order organization of human placental aromatase

Steroids, 2011

Aromatase (CYP19A1) is an integral membrane enzyme that catalyzes the removal of the 19methyl gro... more Aromatase (CYP19A1) is an integral membrane enzyme that catalyzes the removal of the 19methyl group and aromatization of the A-ring of androgens. All human estrogens are synthesized from their androgenic precursors by this unique cytochrome P450. The crystal structure of active aromatase purified from human placenta has recently been determined in complex with its natural substrate androstenedione in the high-spin ferric state of heme. Hydrogen bond forming interactions and tight packing hydrophobic side chains closely complement puckering of the steroid backbone, thereby providing the molecular basis for the androgenic specificity of aromatase. In the crystal, aromatase molecules are linked by a head-to-tail intermolecular interaction via a surface loop between helix D and helix E of one aromatase molecule that penetrates the heme-proximal cavity of the neighboring, crystallographically-related molecule, thus forming in tandem a polymeric aromatase chain. This intermolecular interaction is similar to the aromatase-Cytochrome P450 reductase coupling and is driven by electrostatics between the negative potential surface of the D-E loop region and the positively charged heme-proximal cavity. This loop-to-proximal site link in aromatase is rather unique -there are only a few of examples of somewhat similar intermolecular interactions in the entire P450 structure database. Furthermore, the amino acids involved in the intermolecular contact appear to be specific for aromatase. Higher order organization of aromatase monomers may have implications in lipid integration and catalysis.

Research paper thumbnail of Loss of Cul1 results in early embryonic lethality and dysregulation of cyclin E

Nature Genetics, 1999

The sequential timing of cell-cycle transitions is primarily governed by the availability and act... more The sequential timing of cell-cycle transitions is primarily governed by the availability and activity of key cell-cycle proteins. Recent studies in yeast have identified a class of ubiquitin ligases (E3 enzymes) called SCF complexes, which regulate the abundance of proteins that promote and inhibit cell-cycle progression at the G1-S phase transition. SCF complexes consist of three invariable components, Skp1, Cul-1 (Cdc53 in yeast) and Rbx1, and a variable F-box protein that recruits a specific cellular protein to the ubquitin pathway for degradation. To study the role of Cul-1 in mammalian development and cell-cycle regulation, we generated mice deficient for Cul1 and analysed null embryos and heterozygous cell lines. We show that Cul1 is required for early mouse development and that Cul1 mutants fail to regulate the abundance of the G1 cyclin, cyclin E (encoded by Ccne), during embryogenesis.

Research paper thumbnail of and dysregulation of cyclin E

Research paper thumbnail of How meaningful are data from Likert scales? An evaluation of how ratings are made and the role of the response shift in the socially disadvantaged

Journal of Health Psychology, 2012

Likert scales relating to quality of life were completed by the homeless (N = 75); first year stu... more Likert scales relating to quality of life were completed by the homeless (N = 75); first year students (N = 301) and a town population (N = 72). Participants also completed free text questions. The scale and free text data were often contradictory and the results highlighted three processes to account for these disparities: i) frame of reference: current salient issues influenced how questions were interpreted; ii) within-subject comparisons: ratings were based on expectations given past experiences; iii) time frame: those with more stable circumstances showed habituation to their level of deprivation. Likert scale data should be understood within the context of how ratings are made.

Research paper thumbnail of Homework network exam questions

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