A linear domain decomposition method for two-phase flow in porous media

This article is a follow up of our submitted paper [11] in which a decomposition of the Richards equation along two soil layers was discussed. A decomposed problem was formulated and a decoupling and linearisation technique was presented to solve the problem in each time step in a fixed point type iteration. This article extends these ideas to the case of two-phase in porous media and the convergence of the proposed domain decomposition method is rigorously shown.Comment: 8 page

Epigenetic changes within the promoter region of the HLA-G gene in ovarian tumors

© 2008 Menendez et al; licensee BioMed Central Ltd. The electronic version of this article is the complete one and can be found online at: http://www.molecular-cancer.com/content/7/1/43DOI: 10.1186/1476-4598-7-43Background: Previous findings have suggested that epigenetic-mediated HLA-G expression in tumor cells may be associated with resistance to host immunosurveillance. To explore the potential role of DNA methylation on HLA-G expression in ovarian cancer, we correlated differences in HLA-G expression with methylation changes within the HLA-G regulatory region in an ovarian cancer cell line treated with 5-aza-deoxycytidine (5-aza-dC) and in malignant and benign ovarian tumor samples and ovarian surface epithelial cells (OSE) isolated from patients with normal ovaries. Results: A region containing an intact hypoxia response element (HRE) remained completely methylated in the cell line after treatment with 5-aza-dC and was completely methylated in all of the ovarian tumor (malignant and benign) samples examined, but only variably methylated in normal OSE samples. HLA-G expression was significantly increased in the 5-aza-dC treated cell line but no significant difference was detected between the tumor and OSE samples examined. Conclusion: Since HRE is the binding site of a known repressor of HLA-G expression (HIF-1), we hypothesize that methylation of the region surrounding the HRE may help maintain the potential for expression of HLA-G in ovarian tumors. The fact that no correlation exists between methylation and HLA-G gene expression between ovarian tumor samples and OSE, suggests that changes in methylation may be necessary but not sufficient for HLA-G expression in ovarian cancer

Epigenetic changes within the promoter region of the gene in ovarian tumors-3

reaction) on the ovarian carcinoma cell line BG-1, either untreated (control) or treated with 50 μM 5-aza-deoxycytidine (5-aza-dC). ("-" = samples without RT; "+" = samples with RT). was used as an endogenous control.<p><b>Copyright information:</b></p><p>Taken from "Epigenetic changes within the promoter region of the gene in ovarian tumors"</p><p>http://www.molecular-cancer.com/content/7/1/43</p><p>Molecular Cancer 2008;7():43-43.</p><p>Published online 22 May 2008</p><p>PMCID:PMC2429914.</p><p></p

Epigenetic changes within the promoter region of the gene in ovarian tumors-1

Ncers and regulator binding sites: HRE = hypoxia response element; B2 = enhancer κB2; B1 = enhancer κB1; ISRE = interferon sequence responsive element; W/S= W/S box; X1 = conserved X1 regulatory box; X2 = X2 box; CAAT = CCAAT box; TATA = TATA box; ex1 = exon 1; Met-F and Met-R = forward (F) and reverse (R) primer binding sites. Bisulfite genomic sequencing of 19 CpG dinucleotides of the region from -450 to ATG. Individual CpG dinulcotides are depicted as circles. Each row of circles represents an individual sequenced clone, either untreated (PBS) or treated with 50 μM 5-aza-dC (open circle = 100% unmethylated; filled circle = 100% methylated; %MET = percentage of methylation of each individual clone; %CONV = efficiency of sodium bisulfite treatment).<p><b>Copyright information:</b></p><p>Taken from "Epigenetic changes within the promoter region of the gene in ovarian tumors"</p><p>http://www.molecular-cancer.com/content/7/1/43</p><p>Molecular Cancer 2008;7():43-43.</p><p>Published online 22 May 2008</p><p>PMCID:PMC2429914.</p><p></p

The educational impact of team-skills training: preparing students to work in groups

Background: Despite a vast literature on collaborative learning (CL), there is little research on preparing students to work collaboratively.Aims: This two-phase evaluation investigated whether team-skills training could enhance the performance of collaborative groups through the introduction of a team development programme to a group-based undergraduate key-skills unit.Sample: Phase 1 compared two consecutive cohorts of second-year students, Cohort 1 (N=94) who received no preparation, and Cohort 2 (N=113) who received team-skills training. Phase 2 added Cohort 3 (N=88), who also received team-skills training, to extend the analysis.Method: In Phase 1, students in both Cohorts 1 and 2 worked on a series of curriculum based key-skill tasks across two semesters. Students worked in one group in Semester 1 and were then formed into new groups for Semester 2. Effects of the training were measured by student group marks and key-skill ratings.Results: Marks and key-skill ratings were significantly higher for the trained cohort in Semester 1 (p&lt;.01). However, in Semester 2 performance reduced for the trained cohort in comparison to Semester 1. To explore this further, Phase 2 of the study evaluated Cohort 3, where after training, collaborative groups remained intact throughout the academic year. Results for Cohort 3 showed no attenuation of performance effects in Semester 2.Conclusions: Phase 1 results support the use of team-skills training to enhance CL group performance. The findings for Phase 2 suggest that these benefits may be lost if training groups are disrupted

Gene expression profiling supports the hypothesis that human ovarian surface epithelia are multipotent and capable of serving as ovarian cancer initiating cells

© 2009 Bowen et al; licensee BioMed Central Ltd. The electronic version of this article is the complete one and can be found online at:http://www.biomedcentral.com/1755-8794/2/71DOI: 10.1186/1755-8794-2-71Background Accumulating evidence suggests that somatic stem cells undergo mutagenic transformation into cancer initiating cells. The serous subtype of ovarian adenocarcinoma in humans has been hypothesized to arise from at least two possible classes of progenitor cells: the ovarian surface epithelia (OSE) and/or an as yet undefined class of progenitor cells residing in the distal end of the fallopian tube. Methods Comparative gene expression profiling analyses were carried out on OSE removed from the surface of normal human ovaries and ovarian cancer epithelial cells (CEPI) isolated by laser capture micro-dissection (LCM) from human serous papillary ovarian adenocarcinomas. The results of the gene expression analyses were randomly confirmed in paraffin embedded tissues from ovarian adenocarcinoma of serous subtype and non-neoplastic ovarian tissues using immunohistochemistry. Differentially expressed genes were analyzed using gene ontology, molecular pathway, and gene set enrichment analysis algorithms. Results Consistent with multipotent capacity, genes in pathways previously associated with adult stem cell maintenance are highly expressed in ovarian surface epithelia and are not expressed or expressed at very low levels in serous ovarian adenocarcinoma. Among the over 2000 genes that are significantly differentially expressed, a number of pathways and novel pathway interactions are identified that may contribute to ovarian adenocarcinoma development