Escherichia coli Phosphoenolpyruvate-Dependent Phosphotransferase System. Evidence That the Dimer Is the Active Form of Enzyme I

In vitro kinetic measurements have been performed by using purified HPr, EI, and a membrane fraction of EII from the Escherichia coli phosphoenolpyruvate-dependent sugar transport system. These measurements reveal very large lag times in the formation of methyl α-glucoside phosphate which are a function of the EI and the EII concentrations. The lag times decrease with increasing concentrations of EI but they increase with increasing concentrations of EII. When EI, together with Mg2+ and phosphoenolpyruvate, is preincubated at 37 °C before starting the kinetic measurements, the lag time can be decreased or eliminated. We have shown that the process responsible for the lag time is the activation of EI by dimerization which is influenced by Mg2+ and phosphoenolpyruvate

Use of nonintrusive sensor-based information and communication technology for real-world evidence for clinical trials in dementia

Cognitive function is an important end point of treatments in dementia clinical trials. Measuring cognitive function by standardized tests, however, is biased toward highly constrained environments (such as hospitals) in selected samples. Patient-powered real-world evidence using information and communication technology devices, including environmental and wearable sensors, may help to overcome these limitations. This position paper describes current and novel information and communication technology devices and algorithms to monitor behavior and function in people with prodromal and manifest stages of dementia continuously, and discusses clinical, technological, ethical, regulatory, and user-centered requirements for collecting real-world evidence in future randomized controlled trials. Challenges of data safety, quality, and privacy and regulatory requirements need to be addressed by future smart sensor technologies. When these requirements are satisfied, these technologies will provide access to truly user relevant outcomes and broader cohorts of participants than currently sampled in clinical trials

Overcoming Language Dichotomies: Toward Effective Program Comprehension for Mobile App Development

Mobile devices and platforms have become an established target for modern software developers due to performant hardware and a large and growing user base numbering in the billions. Despite their popularity, the software development process for mobile apps comes with a set of unique, domain-specific challenges rooted in program comprehension. Many of these challenges stem from developer difficulties in reasoning about different representations of a program, a phenomenon we define as a "language dichotomy". In this paper, we reflect upon the various language dichotomies that contribute to open problems in program comprehension and development for mobile apps. Furthermore, to help guide the research community towards effective solutions for these problems, we provide a roadmap of directions for future work.Comment: Invited Keynote Paper for the 26th IEEE/ACM International Conference on Program Comprehension (ICPC'18

Cellulose Gum: a new additive for wine tartaric stability. Tentative of structures determination involved in the haze formation after CMC addition in wine

International audienceCellulose gum (or sodium carboxymethylcellulose / CMC) is a new additive permitted by the European Community for tartaric stabilization (maximum dosage: 10g/HL). CMC is known to have a high eciency for potassium bitartrate and calcium tartrate crystallization inhibition in white and sparkling wines. Hypotheses suggest an inhibition of the nuclei growth at the beginning of their formation. However some problems remain, such as the formation of a low increase of the turbidity in white wine (from 0,1 to 0,4 NTU at room temperature) requiring a ltration step and the formation of a high lumps volume when CMC is used in some red wines. The goal of the following experiments was to determine which molecules are involved in the haze formed in white or red wines. 1. On white wines: A unique Sauvignon wine is treated from 0 up to 600mg/L of activated bentonite. After ltration, each batch was added (or not) with 100mg/L of CMC previously dissolved in tap water (conc.:50g/L). After 1 week of storage at 13°C, samples were heated at 80°C during ½ h and then stored at RT during 24h before running turbidity. 2. On red wines: 1L of red wine (blend of Cinsault, Merlot and Cab. Sauvignon) was added with 100mg/L of CMC (see above) and stored at-4°C for 4 days. After this time, the wine showed a high level of red clouds. At negative temperature, the deposit was ltered on 0.2 µm nitrocellulose lter membrane and extensively washed with a hydro-alcoholic solution (12% ethanol v/v-pH: 3,5/HCl) kept at-4°C. The membrane was then dried under vacuum and the deposit was collected and exchanged 3 times with D2O for H1-NMR study (HRMAS)

When is an Owl More Than an Owl? An Interaction Analysis of a Computer Science Co-design Conversation on Cultural Relevance

The learning sciences community is currently exploring new ways to enact productive and equitable co-design research-practice partnerships that are sensitive to all the concerns and needs of stakeholders. The paper contributes to that still-growing literature through an interaction analysis of a co-design discussion involving school district partners that unfolded about cultural relevance and sensitivity in relation to the use of a specific image in an elementary school coding lesson. The episode involved looking moment-by-moment at how district educators recognized and acknowledged that a specific design decision could be harmful for a minoritized population of students enrolled in the district. However, once a key change was made to be more culturally responsive and considerate, new and unexpected pedagogical challenges appeared. This case serves to illustrate some of the unexpected tensions that can appear in real-time when unanticipated questions about cultural relevance are foregrounded during lesson and materials co-design

Identifying Characteristics of Effective Small Group Learning Valued by Medical Students and Facilitators

Background: Small group teaching is an important part of undergraduate medical education, providing the ideal setting for learners to clarify misunderstandings, test hypotheses and evaluate ideas. Many schools undergoing curriculum reform have increased the time students spend in small group learning. However, there is an overall paucity of literature examining case-based small group sessions in medical school. Objective: This study was designed to examine student and facilitator perceptions of effective case-based small group teaching in the pre-clinical years and compare results in order to identify similarities and differences and identify key areas of disconnect so that the small group learning experience can be improved. Methods: An 18-item survey was emailed to all 388 students who had started the second year of medical school at the University of Massachusetts between August 2008 and August 2010 and to 146 of 161 facilitators who had facilitated a case-based small group session during that same time. Chi-square tests of equality of proportions were used to compare the answers of students and small group facilitators. Results: 79 (54%) small group facilitators and 195 (50%) students responded. Student and facilitator responses were similar in the areas regarding goals of small group sessions and responsibilities of the facilitator. Significant difference was noted between cohorts about the most important roles of the facilitator, whether facilitators and/or students should attend training prior to sessions, whether groups should follow a consistent format, how students should be expected to prepare for small groups, how student knowledge and performance should be assessed, and whether the small group leader should be a skilled facilitator or content expert. Conclusions: This study demonstrates that there are areas where perceptions of effectiveness differ between students and facilitators. Identifying these areas presents an opportunity to make small group sessions more effective by allowing for more informed facilitator development and better communication of session expectations to students. The lack of a substantive body of literature on this important trend in medical education, coupled with our findings, suggests that further study is needed to identify characteristics of case-based small group learning that are mutually valued by students and facilitators. This will encourage the development of small group sessions that are deemed effective and maximize learning and teaching time