Outstanding Mathematics Teachers’ Teaching Practices: A Collective Case Study

This collective case study explored the teaching practices of outstanding mathematics teachers who were purposely chosen using a selection guide by a team of mathematics administrators in Panay Island, Philippines. Researcher-made classroom observation tools (COT), interview protocols, field and reflection notes, lesson plans, and focus group discussions from students were used to gather multiple sources of data. Analyses of pedagogical strategies, including the interactive classroom collaborations, and explanations for those decisions from the teachers were included in the within-case analysis and cross-case analysis. The study depicted detailed verbatim interactions between the teachers and the students during actual teaching episodes to give the reader naturalistic examples of the explanation patterns and strategies that the outstanding teachers used to further students’ understanding of mathematical concepts and procedures. The Philippine Professional Standards for Teachers (PPST) framework was used as guide in the analysis, interpretation, and presentation of the results. These outstanding teachers were noted to be exemplary in planning the teaching and learning process, proficient in using teaching and learning resources including ICT, and excellent in managing the classroom; applied successful teaching strategies in the development of critical and creative thinking as well as of higher-order thinking skills; used appropriate formal and non-formal assessment tools; provided feedback to their learners to rationalize and to improve learning; and constantly communicated their learners’ progress and achievements to parents. Keywords: teaching practices, outstanding mathematics teachers, collective case study DOI: 10.7176/JEP/14-12-07 Publication date: April 30th 202

Influence of wear and overwear on surface properties of etafilcon A contact lenses and adhesion of Pseudomonas aeruginosa

PURPOSE. To determine changes in physicochemical surface properties of contact tenses (CLs) during daily wear and effects of lens wear on adhesion of a Pseudomonas aeruginosa strain from a patient with CL-related keratitis.METHODS. Ten new CL wearers used ionic, etafilcon A lenses with 58% water on both eyes for approximately 10 hours each day during 10 and 50 days. All lenses were treated daily with an appropriate lens care solution. After the CLs were worn for 10 days (first pair of lenses) and 50 days (second pair, representing overwear), hydrophobicity by water contact angles, surface roughness by atomic force microscope, elemental surface composition by x-ray photoelectron spectroscopy (XPS), and adsorbed proteins by SDS-PAGE were determined on one lens. The lens from the contralateral eye was placed in a parallel plate flow chamber for bacterial adhesion after each time interval.RESULTS. Water contact angles on lenses changed from 45degrees on unused lenses to 61degrees +/- 25degrees after 10 days of wear and changed significantly (P &lt;0.05) to 27degrees +/- 14degrees after 50 days of wear. Surface roughness increased significantly (P &lt;0.05) from 4 +/- 2 nm (unused) to 10 +/- 7 nm after 50 days of wear. These changes were accompanied by adsorption of proteinaceous material, as evidenced by XPS and SDS-PAGE, demonstrating adsorption of lysozyme, tear lipocalin, and a 30-kDa protein. Initial bacterial adhesion to worn CLs was lower than to unworn CLs. Furthermore, detachment of adhering bacteria from worn lenses was easier than from unworn lenses. The changes observed in the physicochemical surface properties of the lenses after the CLs were worn for 50 days were accompanied by reports of discomfort by 6 of the 10 new CL wearers. Multiple regression analysis revealed that the most predictive variables for an effect on initial deposition after 10 days of wear were hydrophobicity, roughness, the presence of nitrogen-rich material, including the presence of a 30-kDa protein, and the presence of oxygen-rich material-that is, the type of oxygen adsorbed (O==C or O-C). After 50 days of wear, roughness and the presence of tear lipocalin were most predictive.CONCLUSIONS. This study demonstrates that the physicochemical surface properties changed after wear and overwear, whereas overwear of the lenses decreased initial adhesion of P. aeruginosa #3 under the present experimental conditions.</p

A scalable, fully automated process for construction of sequence-ready human exome targeted capture libraries

Genome targeting methods enable cost-effective capture of specific subsets of the genome for sequencing. We present here an automated, highly scalable method for carrying out the Solution Hybrid Selection capture approach that provides a dramatic increase in scale and throughput of sequence-ready libraries produced. Significant process improvements and a series of in-process quality control checkpoints are also added. These process improvements can also be used in a manual version of the protocol

Despite WT1 binding sites in the promoter region of human and mouse nucleoporin glycoprotein 210, WT1 does not influence expression of GP210

BACKGROUND: Glycoprotein 210 (GP210) is a transmembrane component of the nuclear pore complex of metazoans, with a short carboxyterminus protruding towards the cytoplasm. Its function is unknown, but it is considered to be a major structural component of metazoan nuclear pores. Yet, our previous findings showed pronounced differences in expression levels in embryonic mouse tissues and cell lines. In order to identify factors regulating GP210, the genomic organization of human GP210 was analyzed in silico. RESULTS: The human gene was mapped to chromosome 3 and consists of 40 exons spread over 102 kb. The deduced 1887 amino acid showed a high degree of alignment homology to previously reported orthologues. Experimentally we defined two transcription initiation sites, 18 and 29 bp upstream of the ATG start codon. The promoter region is characterized by a CpG island and several consensus binding motifs for gene regulatory transcription factors, including clustered sites associated with Sp1 and the Wilms' tumor suppressor gene zinc finger protein (WT1). In addition, distal to the translation start we found a (GT)n repetitive sequence, an element known for its ability to bind WT1. Homologies for these motifs could be identified in the corresponding mouse genomic region. However, experimental tetracycline dependent induction of WT1 in SAOS osteosarcoma cells did not influence GP210 transcription. CONCLUSION: Although mouse GP210 was identified as an early response gene during induced metanephric kidney development, and WT1 binding sites were identified in the promoter region of the human GP210 gene, experimental modulation of WT1 expression did not influence expression of GP210. Therefore, WT1 is probably not regulating GP210 expression. Instead, we suggest that the identified Sp binding sites are involved

Oral biofilm models for mechanical plaque removal

In vitro plaque removal studies require biofilm models that resemble in vivo dental plaque. Here, we compare contact and non-contact removal of single and dual-species biofilms as well as of biofilms grown from human whole saliva in vitro using different biofilm models. Bacteria were adhered to a salivary pellicle for 2 h or grown after adhesion for 16 h, after which, their removal was evaluated. In a contact mode, no differences were observed between the manual, rotating, or sonic brushing; and removal was on average 39%, 84%, and 95% for Streptococcus mutans, Streptococcus oralis, and Actinomyces naeslundii, respectively, and 90% and 54% for the dual- and multi-species biofilms, respectively. However, in a non-contact mode, rotating and sonic brushes still removed considerable numbers of bacteria (24–40%), while the manual brush as a control (5–11%) did not. Single A. naeslundii and dual-species (A. naeslundii and S. oralis) biofilms were more difficult to remove after 16 h growth than after 2 h adhesion (on average, 62% and 93% for 16- and 2-h-old biofilms, respectively), while in contrast, biofilms grown from whole saliva were easier to remove (97% after 16 h and 54% after 2 h of growth). Considering the strong adhesion of dual-species biofilms and their easier more reproducible growth compared with biofilms grown from whole saliva, dual-species biofilms of A. naeslundii and S. oralis are suggested to be preferred for use in mechanical plaque removal studies in vitro

Investigating secondary mathematics teachers’ self-efficacy beliefs, TPACK and challenges towards technology integration

This study investigated the perceived self-efficacy beliefs towards technology integration and technological, pedagogical and content knowledge (TPACK-M) of high school mathematics teachers along with the challenges they encounter in integrating technology in their classrooms. Using a survey questionnaire, the respondents reported a moderately high self-efficacy beliefs and measures of knowledge in TPACK-M constructs with significant predictive relationship between these variables. The teachers differ in their beliefs and knowledge when grouped according to their gender but not by their age and years of teaching experience. The challenges they encountered include limited technology resources, poor or lack of internet connection, insufficient technological skills, power interruptions, and students’ unfavorable attitudes and inadequate computer skills. To ascertain the actualities of technology integration within school contexts, it is recommended that class observations and interviews will be done