The Effects of Electrolyte Chemical Composition, Concentration and pH on the Electrochemical Redox Reactions

Electrolyte composition, concentration, pH, ionic strength, and temperature have long been known to play a role in the interface of the electrode-electrolyte. However, detailed studies are not sufficient. Cyclic voltammetry (CV) is a widely used electrochemical technique for obtaining qualitative information in electroanalysis. CV is often the first experiment performed in an electrode surface in an electrochemical study. It measures the number of electrons transferred and intermediates formed during oxidation-reduction (redox) reactions by observing its current, intensity and position of peak potential with applied voltage. This is accomplished by using a three-electrode system including working electrode (WE), counter electrode (CE) and reference electrode (RE). In this work, our system consists of gold (Au) We, platinum (PT) CE and silver/silver chloride (Ag/AgCl) RE. The potential relative to the reference electrode is forward- and reverse-scanned at the working electrode while the current flows through the counter electrode is observed in a solution. In this study, we investigate systematically the redox potential of the different analytes under various conditions in concentration and pH. Therefore, this study can be referenced for studies in exploring a variety range of biological samples, cells, tissues, lipids, and proteins on surfaces

What's the smallest part of spinach? A new experimental approach to the count/mass distinction

This paper reports on a study that uses a novel methodology, the minimal part identification task, in order to probe the relationship between morphosyntax and interpretation. English, Korean and Mandarin Chinese differ from one another with regard to the count/mass distinction. Building on prior research but using a new methodology, this study examines whether speakers of these three languages also differ in how they interpret count vs. mass nouns. The findings, while uncovering some language-specific effects of morphosyntax, point to the importance of universality, and suggest that interpretation drives morphosyntax rather than the other way around

Quantitative evaluation and reversion analysis of the attractor landscapes of an intracellular regulatory network for colorectal cancer

The molecular profiles of CMS cancer cells, statistical significance analysis of reversion targets, and synergistic effect analysis of every two nodes inhibition. (XLSX 67 kb

Synergistic Effects of Simvastatin and Irinotecan against Colon Cancer Cells with or without Irinotecan Resistance

Aims. We here investigated whether the combination of simvastatin and irinotecan could induce the synergistic effect on colon cancer cells with or without resistance to irinotecan. Methods. We investigated cell proliferation assay and assessed cell death detection ELISA and caspase-3 activity assay of various concentrations of simvastatin and irinotecan to evaluate the efficacy of drug combination on colon cancer cells with or without irinotecan resistance. Results. The IC50 values of simvastatin alone and irinotecan alone were 115.4±0.14 μM (r=0.98) and 62.5±0.18 μM (r=0.98) in HT-29 cells without resistance to irinotecan. The IC50 values of these two drugs were 221.9±0.22 μM (r=0.98) and 195.9±0.16 μM (r=0.99), respectively, in HT-29 cell with resistance to irinotecan. The results of combinations of the various concentrations of two drugs showed that combined treatment with irinotecan and simvastatin more efficiently suppressed cell proliferation of HT-29 cells even with resistance to irinotecan as well as without resistance. Furthermore, the combination of simvastatin and irinotecan at 2:1 molar ratio showed the best synergistic interaction. Conclusion. Simvastatin could act synergistically with irinotecan to overcome irinotecan resistance of colon cancer

Limits on spin-dependent WIMP-nucleon cross sections from 225 live days of XENON100 data

We present new experimental constraints on the elastic, spin-dependent WIMP-nucleon cross section using recent data from the XENON100 experiment, operated in the Laboratori Nazionali del Gran Sasso in Italy. An analysis of 224.6 live days x 34 kg of exposure acquired during 2011 and 2012 revealed no excess signal due to axial-vector WIMP interactions with 129-Xe and 131-Xe nuclei. This leads to the most stringent upper limits on WIMP-neutron cross sections for WIMP masses above 6 GeV, with a minimum cross section of 3.5 x 10^{-40} cm^2 at a WIMP mass of 45 GeV, at 90% confidence level

Observation and applications of single-electron charge signals in the XENON100 experiment

The XENON100 dark matter experiment uses liquid xenon in a time projection chamber (TPC) to measure xenon nuclear recoils resulting from the scattering of dark matter Weakly Interacting Massive Particles (WIMPs). In this paper, we report the observation of single-electron charge signals which are not related to WIMP interactions. These signals, which show the excellent sensitivity of the detector to small charge signals, are explained as being due to the photoionization of impurities in the liquid xenon and of the metal components inside the TPC. They are used as a unique calibration source to characterize the detector. We explain how we can infer crucial parameters for the XENON100 experiment: the secondary-scintillation gain, the extraction yield from the liquid to the gas phase and the electron drift velocity

The effects of written corrective feedback on second language writing focused on the English articles system

The present study explored the effectiveness of different types of written corrective feedback and error logs in L2 writing focused on English articles. For this study, during a semester, 25 undergraduate students in two intact ESL writing courses received implicit or explicit feedback while one of the classes were asked to keep error logs after receiving corrective feedback. To examine students’ improvement, analysis of four writing tasks and a grammaticality judgment test were carried out. Statistical analysis of the data showed that corrective feedback was effective on the acquisition of English articles, and keeping error logs after receiving corrective feedback was effective to help students to better retain the received corrective feedback. The results also showed that implicit corrective feedback was more effective than explicit corrective feedback when students were asked to keep error logs after receiving corrective feedback while explicit corrective feedback was more effective when they did not keep error logs. The results suggest that receiving corrective feedback and keeping error logs can have a positive effect on L2 acquisition and the effectiveness of implicit and explicit feedback can be affected by other variables

The count/mass distinction in native and non-native grammar

This dissertation investigates whether the interpretation of different types of nouns is affected by count/mass morphosyntax and whether second language (L2) learners are affected by first language (L1) transfer from their native language or are instead affected by semantic universals in L2 acquisition of the count/mass distinction. Furthermore, this dissertation also examines how similarly/differently L2-learners behave in online and offline tasks regarding the acquisition of the count/mass morphosyntax in English. As current literature does not provide a conclusive answer to these questions, three experiments were conducted to address this gap. Experiment 1 investigates whether L2-learners transfer the properties of plural marking from their native language to their L2 regarding object-mass nouns. Native speakers (NSs) of English, L1-Korean L2-English learners, and L1-Mandarin L2-English learners were compared. The results show no transfer effects, but L2-learners’ performances were affected by semantic universals (atomicity). Furthermore, it was also found that L2-learners show the exact same patterns in online and offline tasks, suggesting that L2-learners’ knowledge about how atomicity relates to the count/mass distinction (specifically, the mapping between plural marking and atomicity) is present at both explicit and implicit levels. Experiments 2a, 2b, and 2c examine whether the interpretation of different nouns is affected by the count/mass morphosyntax or universality in native and non-native grammar. In this set of experiments, NSs of English, Korean, and Mandarin Chinese and L1-Korean L2-English learners and L1-Mandarin L2-English learners were tested and compared. The results indicate that the interpretation of different types of nouns were affected by semantic universals (atomicity) without L1-transfer effects from the count/mass morphosyntax of their L1s. Experiments 3a and 3b investigate whether L2-learners transfer the properties of plural marking from their native language to their L2 with respect to flexible nouns. In these two experiments, English NSs, L1-Korean L2-English learners, and L1-Mandarin L2-English learners were compared. The results show that L2-learners, though not affected by L1-transfer, were affected by semantic universals (atomicity) in their use of flexible nouns. Furthermore, unlike in Experiment 1, it was found that L2-learners performed better in the offline task than in the online task, suggesting that L2-learners’ knowledge about how atomicity relates to the count/mass distinction is better at the explicit level than the implicit level. A possible reason for such differences in the results between Experiment 1 and Experiments 3a and 3b is that interpretation trumps morphosyntax with object-mass nouns while the judgments of flexible nouns are flexible. Thus, it is possible that flexible judgments on flexible nouns are what led learners to be successful on the GJT to some extent. Taken together, this dissertation shows that universality (atomicity), and not L1-transfer, plays a role in the interpretation of different types of nouns and in the L2-acquisition of the count/mass distinction in English. This dissertation also demonstrates that L2-learners’ knowledge at explicit and implicit levels are separate with L2-learners having different explicit and implicit knowledge depending on noun type.LimitedAuthor requested closed access (OA after 2yrs) in Vireo ETD syste

Strategy, Structure and Performance of Korean Business Groups: A Transactions Cost Approach.

The authors use the transactions cost approach to analyze the diversification strategy and the resulting structure chosen by Korean business groups to overcome market imperfections prevalent in developing countries. Business groups that have multidivisional struc ture are thought to show superior economic performance because such s tructure reduces transactions costs arising from organizational failure. Also, major Korean business groups have a "relational structure," showing both vertical integration and the characteristics of the conglomerate. The authors modify the model of R. E. Caves and M. Uekusa (1976), used for Japan, to obtain the empirical result tha t group-affiliated firms show superior economic performance. Copyright 1988 by Blackwell Publishing Ltd.