Modeling a Field Application of In Situ Bioremediation of Perchlorate-Contaminated Groundwater Using Horizontal Flow Treatment Wells (HFTWs)

Perchlorate contaminated groundwater is rapidly becoming a significant environmental remediation issue for the Department of Defense. In this study, an existing numerical model that simulates the operation of a Horizontal Flow Treatment Well (HFTW) system to effect the in situ biodegradation of perchlorate through the addition of an electron donor is modified to include a submodel that describes bioclogging. Bioclogging restricts flow out of the HFTW due to the accumulation of biomass directly adjacent to the well. The modified model is then applied to an existing perchlorate contaminated site that will be used for an evaluation of the HFTW technology. Simulations were conducted to determine the impact of altering various engineered parameters on HFTW performance. Simulation results indicate that higher time averaged electron donor concentrations and HFTW pumping rates lead to more perchlorate degradation in terms of total mass of perchlorate removed. Simulation results also indicate that varying the electron donor addition schedule has little impact on HFTW performance. The simulations conducted in this study show that, regardless of the engineered parameter values, bioclogging does not impact the ability of the HFTW technology to effect in situ biodegradation of perchlorate at the evaluation site

AUXIN-INDUCED DEGRADATION OF DREAM PROTEINS, LIN-9 AND LIN-54, IN CAENORHABDITIS ELEGANS

The Dp, Retinoblastoma, E2F, And MuvB (DREAM) complex mediates transcriptional repression and is highly conserved throughout a number of species, including vertebrates, Drosophila melanogaster, and Caenorhabditis elegans. Differing from mammalian DREAM, C.elegans DRM, appears to act solely in a repressive role, with the MuvB subcomplex (LIN-9, LIN-37, LIN-52, LIN-53, and LIN-54) playing a key role in the repression of genes. In this study, we use the auxin-inducible degron (AID) system, an effective, fast-acting, tool used in the degradation of degron-tagged proteins to individually deplete two key proteins of the MuvB subcomplex, LIN-9 and LIN-54, in C. elegans. The AID system relies on the expression of the F-box protein, transport inhibitor response 1 (TIR1), which in the presence of auxin acts as the substrate recognition component for the SKP1-CUL1-F-box (SCF) E3 ubiquitin ligase complex, leading to the degradation of tagged proteins. In degron-tagged LIN-54 worms, using a 6-hour auxin time course, we observed that DREAM target genes become significantly upregulated. Expression of DREAM target genes increased with longer exposure to auxin, indicating that LIN-54 plays a key role in the regulation of DREAM target genes. However, in both a 6-hour and 24-hour auxin time course experience, degron-tagged LIN-9 worms showed no uniform nor significant upregulation of DREAM target genes compared to ethanol vehicle control. These results demonstrate that LIN-54, the sole DNA-binding protein of MuvB, plays a more important role in MuvB’s repression of genes than the core protein of MuvB, LIN-9. We recommend further study into these two proteins using the AID system to further explore their roles in MuvB and DREAM complex function

IS FLIPPED LEARNING FOR EVERYONE?

An education crisis happens in Indonesia and therefore many policies and efforts are implemented to uplift the quality of its education. The government is committed to improve the infrastructure in the country’s education system so that the students will have better experience in the future. This study analyzes flipped learning as one of the strategies in blended learning that incorporates variety of methods in delivering the content of Lessons in English classroom context. By implementing transcendental phenomenology, this study aims at finding a description on how the students give meaning on the implementation of flipped learning in their Interpreting class. This study tried to capture the narrative description of the students’ lived experience and depicted the emerging themes from the analysis of the students’ understanding, belief, feeling, intention and action. The themes emerged in this study were collaboration, discipline, self-actualization and self-empowerment

Perceived Choices of Graduation among Master Students: Expectancy-Task Value Theoretical Perspective

This study investigated whether motivational beliefs (expectancy of success and value in research and practice related tasks) among master students predict the achievement related choices for graduation (thesis or non-thesis) and examined the likelihood of those motivational beliefs in thesis and non-thesis preferring group. Participants studied in various master programs of two universities in Cambodia completed the questionnaires about their expectancy of success and values toward research and practice related tasks and preferences of graduation. Results of logistic regression analysis revealed that, among the motivational beliefs, only cost in research indicated a significant predictor of graduation preferences (p = .003). Furthermore, the associated likelihood of thesis preferring group was anchored at students who have higher positive beliefs on cost in research (ß = 2.386, p = .003, Exp (ß) = 10.867, Odd = 986.9), interest in research (ß = .933, p = .431, Exp (ß) = 2.542, Odd = 154.2), utility in practice (ß = .835, p = .226, Exp (ß) = 2.306, Odd = 130.6), and attainment in research (ß = .218, p = .699, Exp (ß) = 1.243, Odd = 24.3) although the rest of expectancy-values components was not completely discriminated in its membership model. Implications of the findings to graduate programs and future direction are discussed

On the Choice of -shihajimeta and -shihajimetatokoroda

This study focused on two forms expressing the “beginning” of the situation, -shihajimeta and -shihajimetatokoroda, and considered their differences. In previous research, -shihajimeru is considered to express the so-called“ starting phase” of the situation, although the actual use of -shihajimeta and -shihajimetatokoroda shows that -shihajimetatokoroda expresses the “starting phase” of the situation. I argue that -shihajimeta expresses“ transition to this situation” as an event. In addition, the sentence type differs between -shihajimeta and -shihajimetatokoroda. Thus, the difference in sentence type could be related to the type of adverbs that co-occur in each form and the different functions the forms play in discourse