Users of Social Networking Sites (SNSs) like Facebook, MySpace, LinkedIn, or Twitter face two problems 1) their online social friendships and activities are scattered across SNSs. It is difficult for them to keep track of all their friends and the information about their friends online social activities. 2) they are often overwhelmed by the huge amount of social data (friends updates and other activities). To solve these two problems, this research proposes an approach, named SocConnect. Soc- Connect allows users to create personalized social and semantic contexts for their social data. Users can blend their friends across different social networking sites and group them in different ways. They can also rate friends and/or their activities as favourite, neutral or disliked. SocConnect also can recommend unread friend updates to the user based on user previous ratings on activi- ties and friends, using machine learning techniques. The results from one pilot studies show that users like SocConnects functionalities are needed and liked by the users. An evaluation of the effectiveness of several machine learning algorithms demonstrated that , and machine learning can be usefully applied in predicting the interest level of users in their social network activities, thus helping them deal with the network overload.

Despite thirty published evaluation reports citing the effectiveness of Vancouver’s safe injection site (Small 2008), the Canadian federal government refuses to endorse safe injection sites as a health service option available to injection drug users (IDUs). Insite’ s evaluation results are undergoing debate, because two communicative spheres of knowledge, each with a unique authoritative language, are conflicting as each is attempting to gain moral authority over the right to recontextualize drug users. Drawing on a literature review of two harm reduction programs in Vancouver, Insite and Sheway, and expert interviews with evaluators, I show that what constitutes “evidence” is in fact subjective, determined by spheres of communicability that are built upon social, professional and political contexts. To confront the problematic nature of this issue, I suggest that evaluators and overseers need to treat program evaluation as a process of negotiation, best approached in a fluid manner. By obscuring multiple user experiences in the evaluation of harm reduction programs, evaluators and overseers risk imposing their communicative ideologies on what it means to be a drug user.

Hox proteins are evolutionarily conserved transcription factors that control important developmental pathways in morphogenesis of the embryo. The Hoxa2 gene is expressed in the developing central nervous system in rhombomeres 2 to 7 and affects cellular differentiation. Few target genes of Hoxa2 protein have been identified so far and its mechanisms of regulating gene expression remain elusive. Previous work in our laboratory isolated Hoxa2 protein binding sequences from the E18 mouse spinal cord and hindbrain tissues using chromatin immunoprecipitation (ChIP). All isolated DNA fragments contain conserved GATG motifs. Sequence analysis revealed that one fragment belongs to the high temperature requirement factor A 3 (HtrA3) gene and another fragment belongs to the Dual specificity tyrosine kinase 4 (Dyrk4) gene. In this study, direct binding of Hoxa2 protein to the HtrA3 and Dyrk4 fragments was confirmed by electrophoretic mobility shift assays (EMSA). Site-directed mutagenesis and EMSA studies revealed that Hoxa2 protein binds to the multiple GATG motifs within these fragments. HtrA3 fragment also repressed luciferase gene expression in transient transfection and luciferase assays. Mutation of the DNA fragment showed that the repressive activity was affected by the GATG motifs, suggesting Hoxa2 protein regulated gene expression by binding to the GATG motif in the cis-regulatory element. In contrast to the inhibitory activity of Hoxa2 protein, a Hoxa2-VP16 fusion protein (Hoxa2 fused with an activation domain of a virion protein from herpes simplex virus) transactivates the luciferase expression by binding to GATG sites. RT-PCR and immunohistochemistry analysis revealed an upregulation of HtrA3 expression in Hoxa2-/- mice. This observation correlates with the inhibitory role of Hoxa2 protein acting upon the HtrA3 fragment in luciferase assays. Our data suggest that HtrA3 is a direct in vivo downstream target of Hoxa2 protein and support the activity regulation model in which Hox proteins selectively regulate target genes through occupation of multiple monomer binding sites.

Users of Social Networking Sites (SNSs) like Facebook, MySpace, LinkedIn, or Twitter face two problems 1) their online social friendships and activities are scattered across SNSs. It is difficult for them to keep track of all their friends and the information about their friends online social activities. 2) they are often overwhelmed by the huge amount of social data (friends updates and other activities). To solve these two problems, this research proposes an approach, named SocConnect. Soc- Connect allows users to create personalized social and semantic contexts for their social data. Users can blend their friends across different social networking sites and group them in different ways. They can also rate friends and/or their activities as favourite, neutral or disliked. SocConnect also can recommend unread friend updates to the user based on user previous ratings on activi- ties and friends, using machine learning techniques. The results from one pilot studies show that users like SocConnects functionalities are needed and liked by the users. An evaluation of the effectiveness of several machine learning algorithms demonstrated that , and machine learning can be usefully applied in predicting the interest level of users in their social network activities, thus helping them deal with the network overload.

The genetic defects that results in TAL1 oncogene activation are commonly seen in leukemic cells of the patient with T-cell Acute Lymphoblastic Leukemia ( T-ALL ). The ectopic expression of TAL1 oncoprotein perturbs the development of T-cell, hence promotes the formation of leukemia. TAL1 gene encodes proteins with basic helix-loop-helix ( bHLH ) domain, a protein dimerization and DNA binding domain. In T-ALL cells, two Tal1 proteins, pp42(1-331 amino acids) and pp22(176-331 amino acids) are produced that both contain bHLH domain. Both proteins interact with immunoglobulin gene enhancer binding protein, E12/E47 to form DNA-binding heterodimers, that can bind to consensus E-box DNA sequence AACAGATGGT. Phosphorylation of S122 residue modulates the trans-activation potential of Tal1 protein. In addition, S172 is an inducible c-AMP dependent protein kinase (PKA) phosphorylation site in vivo. The phosphorylation of TAL1 S172 upon stimulation by forskolin can increase the DNA binding of E12-Tal1 heterodimer. We used site-directed mutagenesis to investigate the effect of S194,S224 mutation on the function of truncated Tal1 oncoprotein.Mutant Tal1 and E12 proteins expression plasmids were constructed and introduced into COS-1 cells by cotransfection. Tal1 and E12 protein expression in transfected cell were evaluated by Western blotting. The protein-DNA interaction were evaluated by electrophorectic mobility shift assay. The mutation of S194 and S224 of Tal1 protein all resulted in the loss of DNA-binding complex formation. This data indicated that these serine residues are essential for bHLH function. However, the phosphorylation status of these two residues in vivo, and what kinase is responsible for the phosphorylation of these residues, await further investigation.

Abstract The purpose of this study was to evaluate the efficiency of biosparging for in situ remediation of groundwater at a site contaminated by petrochemicals. To this end, laboratory-scale (lab-scale for short) and pilot-scale tests were carried out. In the lab-scale study, three possible ways (i.e., by injecting air, by adding hydrogen peroxide, and by adding magnesium peroxide) of increasing the dissolved oxygen content in the groundwater were evaluated in terms of the resulting total bacterial count. Under the conditions used in this work, air injection was found to the most effective one. By injecting compressed air into the mixture of petrochemicals-contaminated soil and groundwater at a flow rate of 175mL/min for five minutes, the total bacterial count of the aerobic bacteria was increased greatly from 102CFU/mL to 107CFU/mL. The concentrations of benzene, toluene, ethyl benzene, and xylenes (BTEX) also were reduced to lower than 0.5£gg/L. Based on the findings obtained from the lab-scale study, air injection was adopted for the enhancement of pilot-scale in situ bioremediation of petrochemicals-contaminated groundwater at a selected site in a petrochemical plant. To evaluate the treatment efficiency of biosparging for the removal of BTEX and naphthalene, in addition to an upstream groundwater well, six one-meter-apart monitoring wells were installed in at the test site the flow direction of groundwater. In the center of the test site, one air injection well and ten soil gas monitoring points also were installed to determining the radius of influence of the air injection well. It was found that an air injection rate of 40L/min was capable of providing sufficient air to all of the monitoring wells of groundwater and increasing the total bacterial count of aerobic bacteria from the order of 102CFU/mL to 106CFU/mL. For a test period of 99 days, the concentrations of all target contaminants in each groundwater monitoring well were decreased markedly. More specifically, the total organic carbon was reduced from 12.7-43.4 mg/L to 3.5-14.9 mg/L; biochemical oxygen demand, from 124-526 mg/L to 43-153 mg/L; benzene; toluene, from 29.88-62.34 mg/L to 11.72-12.82 mg/L ; ethyl benzene, from 0.92-5.30 mg/L to 0.86 mg/L-< 0.5£gg/L; xylenes, from 9.31-47.58 mg/L to 4.07 mg/L -< 0.5£gg/L; and naphthalene, from15.31-0.92 mg/L to < 0.5 £gg/L. Additionally, pH, temperature, and concentrations of various cations determined for the groundwater as well. During the 99-day test period, the following were found: pH varied in the range of 6.75-7.45; temperature, 30-32¢J; Ca2+, 45-65 mg/L; Mg 2+, 16-24 mg/L; Na+, 35-60 mg/L; K+, 8-14 mg/L; and total iron, 2.0-4.0 mg/L. Thus, under the conditions used in this work, the biosparging technology employed was found to have an overall treatment efficiency of over 60% for BTEX and 100% for naphthalene. To increase the overall treatment efficiency, a prolonged air injection is needed at this test site. Keywords: biosparging, groundwater, contaminated site, petrochemicals

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Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xix, 315 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: William S. Dancey, Dept. of Anthropology. Includes bibliographical references (p. 201-230).