MICELLE TO LAMELLAR AGGREGATE TRANSITION OF AN ANIONIC SURFACTANT IN DILUTE AQUEOUS-SOLUTION INDUCED BY ALKALI-METAL CHLORIDE AND TETRAALKYLAMMONIUM CHLORIDE SALTS

Micelles of the anionic surfactant sodium dodecylbenzenesulfonate (NaDoBS) in dilute aqueous solution can be transformed into lamellar aggregates by the addition of alkali metal chloride (LiCl to CsCl) and tetraalkylammonium chloride (alkyl is methyl or n-butyl) salts. Depending on the type of cation, concentration of salt, and isomeric purity of the alkyl chain of the surfactant, different types of phases are observed: large unilamellar vesicles, multivesicular vesicles, and flocculated multilamellar vesicles (lamellar droplets). Over limited concentration ranges, some salts induce phase separation in a surfactant-rich and a surfactant-lean phase. The formation of the different phases was monitored by turbidity and fluorescence depolarization measurements, whereas the phases were characterized by light microscopy, freeze-fracture electron microscopy, and confocal scanning laser microscopy. Thermodynamic aspects of aggregation, in particular the counterion binding characteristics, were studied by microcalorimetry and conductivity. On a molecular level, the packing in a lamellar array can be explained largely in terms of a change in counterion binding and, to a lesser extent, by a decrease of the hydration of the headgroup and the. counterion. A better counterion binding is facilitated by a less hydrated cation or by an increase of the electrolyte concentration. The formation of different types of lamellar aggregates is due to different types of interactions between lamellar layers or between aggregates: largely repulsive for stable dispersions of unilamellar vesicles to attractive down to short distances for the flocculated lamellar droplets

Physicians’ Perspective From a Survey

Background: As a result of demographic changes, physicians are required to deliver needed services with limited resources. Research suggests that tablet PCs with access to patient data may streamline clinical workflow. A recent study found tablets with mobile electronic medical records (EMRs) can facilitate data retrieval and produce time savings across the clinical routine within hospital settings. However, the reasons for these time savings, including details on how tablets were being used, remain unclear. The same applies to physicians’ perceptions of this tool within an inpatient setting. Objective: This study examined physicians’ perception of tablets with EMRs in an inpatient setting. The rationale was to identify both subjective and objective factors that impacted the successful implementation and use of tablets running an EMR. Methods: We developed a 57-item survey questionnaire designed to examine users’ perception of and attitude toward tablets, which was administered to 14 participating physicians following 7 weeks of tablet use. Five participants volunteered to participate in a second study that investigated physicians’ patterns of tablet use within the EMR environment by digitally tracking and storing usage behavior. Statistical analyses of questionnaire results included mean values with their bootstrapped 95% confidence intervals and multivariate analysis of variance to identify predictors of tablet use. Results: Physicians reported high degrees of satisfaction with the tablets. There was a general consensus among physicians that tablet use streamlined clinical workflow through optimized data retrieval (rated 0.69, 0.23-1.15 points better than control) and improved communication with patients and other physicians (rated 0.85, 0.54-1.15 and 0.77, 0.38-1.15 points better than control, respectively). Age (F3,11=3.54, P=.04), occupational group (F1,11=7.17, P=.04), and attitude toward novel technologies (F1,11=10.54, P=.02) predicted physicians’ satisfaction with the devices and their motivation regarding their further use. Tracking data yielded that only a few of the available functions were used frequently. Conclusions: Although tablet PCs were consistently perceived as beneficial, several factors contributed to the fact that their full potential was not fully exploited. Training in functionality and providing a reliable infrastructure might foster successful tablet implementation

Diseño y desarrollo de un sistema basado en Learning Analytics para evaluar la competencia de trabajo en equipo.Design and development of a Learning Analytics System to evaluate group work competence

La adquisición de la competencia grupal es algo básico en la docencia universitaria. Esta tarea va a suponer evaluar diferentes factores en un número elevado de alumnos, lo que puede supone gran complejidad y un esfuerzo elevado. De cara a evitar este esfuerzo se puede pensar en emplear los registros de la interacción de los usuarios almacenados en las plataformas de aprendizaje. Para ello el presente trabajo se basa en el desarrollo de un sistema de Learning Analytics que es utilizado como herramienta para analizar las evidencias individuales de los distintos miembros de un equipo de trabajo. El trabajo desarrolla un modelo teórico apoyado en la herramienta, que permite relacionar las evidencias observadas de forma empírica para cada alumno, con indicadores obtenidos tanto de la acción individual como cooperativo de los miembros de un equipo realizadas a través de los foros de trabajo. Abstract — The development of the group work competence is something basic in university teaching. It should be evaluated, but this means to analyze different issues about the participation of a high number of students which is very complex and implies a lot of effort. In order to facilitate this evaluation it is possible to analyze the logs of students’ interaction in Learning Management Systems. The present work describes the development of a Learning Analytics system that analyzes the interaction of each of the members of working group. This tool is supported by a theoretical model, which allows establishing links between the empirical evidences of each student and the indicators of their action in working forums

Safety Aspects, Tolerability and Modeling of Retinofugal Alternating Current Stimulation

Background While alternating current stimulation (ACS) is gaining relevance as a tool in research and approaching clinical applications, its mechanisms of action remain unclear. A review by Schutter and colleagues argues for a retinal origin of transcranial ACS’ neuromodulatory effects. Interestingly, there is an alternative application form of ACS specifically targeting α-oscillations in the visual cortex via periorbital electrodes (retinofugal alternating current stimulation, rACS). To further compare these two methods and investigate retinal effects of ACS, we first aim to establish the safety and tolerability of rACS. ObjectiveThe goal of our research was to evaluate the safety of rACS via finite-element modeling, theoretical safety limits and subjective report. Methods20 healthy subjects were stimulated with rACS as well as photic stimulation and reported adverse events following stimulation. We analyzed stimulation parameters at electrode level as well as distributed metric estimates from an ultra-high spatial resolution magnetic resonance imaging (MRI)-derived finite element human head model and compared them to existing safety limits. ResultsTopographical modeling revealed the highest current densities in the anterior visual pathway, particularly retina and optic nerve. Stimulation parameters and finite element modeling estimates of rACS were found to be well below existing safety limits. No serious adverse events occurred. ConclusionOur findings are in line with existing safety guidelines for retinal and neural damage and establish the tolerability and feasibility of rACS. In comparison to tACS, retinofugal stimulation of the visual cortex provides an anatomically circumscribed model to systematically study the mechanisms of action of ACS

An investigation into the perspectives of providers and learners on MOOC accessibility

An effective open eLearning environment should consider the target learner’s abilities, learning goals, where learning takes place, and which specific device(s) the learner uses. MOOC platforms struggle to take these factors into account and typically are not accessible, inhibiting access to environments that are intended to be open to all. A series of research initiatives are described that are intended to benefit MOOC providers in achieving greater accessibility and disabled learners to improve their lifelong learning and re-skilling. In this paper, we first outline the rationale, the research questions, and the methodology. The research approach includes interviews, online surveys and a MOOC accessibility audit; we also include factors such the risk management of the research programme and ethical considerations when conducting research with vulnerable learners. Preliminary results are presented from interviews with providers and experts and from analysis of surveys of learners. Finally, we outline the future research opportunities. This paper is framed within the context of the Doctoral Consortium organised at the TEEM'17 conference

Statistical analysis of reinforced concrete bridges in Estonia

This paper introduces a possible way to use a multivariate methodology, called principal component analysis, to reduce the dimensionality of condition state database of bridge elements, collected during visual inspections. Attention is paid to the condition assessment of bridges in Estonian national roads and collected data, which plays an important role in the selection of correct statistical technique and obtaining reliable results. Additionally, detailed overview of typical road bridges and examples of collected information is provided. Statistical analysis is carried out by most natural reinforced concrete bridges in Estonia and comparison is made among different typologies. The introduced multivariate technique algorithms are presented and collated in two different formulations, with contrast on unevenness in variables and taking into account the missing data. Principal components and weighing factors, which are calculated for bridges with different typology, also have differences in results and element groups where variation is retainedTU1406 – Quality Specifications for Roadway Bridges, standardiza- tion at a European level (BridgeSpec), a COST Action sup- ported by EU Framework Programme Horizon 2020info:eu-repo/semantics/publishedVersio

Enhancing the Educational Environment: Improving Student Outcome Using Visual Supports

Students in varying educational settings are supplied with varying levels of academic support. While it is well known that academic supports assist students in learning academic content, visual supports are proven to improve and develop academic language and improve academic proficiency. Visual supports assist students in becoming more knowledgeable of academic content by increasing student engagement and the implementation of classroom structure. The overall focus of this research project was to determine the effectiveness of visual academic supports within primary education, specifically the behavioral and academic impacts of visual aids in a Communication and Social Skills (CSS) classroom at Willow Grove Elementary School within the Duval County School District. The preliminary conclusions of the study are that the visual supports made more consistent academic impacts than behavioral impacts on the students observed

Assessment of extreme hydrological conditions in the Bothnian Bay, Baltic Sea, and the impact of the nuclear power plant “Hanhikivi-1” on the local thermal regime

The results of the study aimed to assess the influence of future nuclear power plant “Hanhikivi-1” upon the local thermal conditions in the Bothnian Bay in the Baltic Sea are presented. A number of experiments with different numerical models were also carried out in order to estimate the extreme hydro-meteorological conditions in the area of the construction. The numerical experiments were fulfilled both with analytically specified external forcing and with real external forcing for 2 years: a cold year (2010) and a warm year (2014). The study has shown that the extreme values of sea level and water temperature and the characteristics of wind waves and sea ice in the vicinity of the future nuclear power plant can be significant and sometimes catastrophic. Permanent release of heat into the marine environment from an operating nuclear power plant will lead to a strong increase in temperature and the disappearance of ice cover within a 2 km vicinity of the station. These effects should be taken into account when assessing local climate changes in the future

Multivariate morphometric analysis of Apis cerana of southern mainland Asia

Multivariate morphometric analyses were performed on a series of worker honeybees, Apis cerana, representing 557 colonies from all of southern mainland Asia extending from Afghanistan to Vietnam south of the Himalayas. Scores from the principal components analysis revealed five statistically separable but not entirely distinct morphoclusters of bees: (1) the Hindu Kush, Kashmir, N. Myanmar, N. Vietnam and S. China; (2) Himachal Pradesh region of N. India; (3) N. India, Nepal; (4) central and S. Myanmar and Vietnam, Cambodia, Thailand, S. China and peninsular Malaysia; (5) central and S. India. The major morphoclusters are distributed coherently with the different climatic zones of the region. While populations are definable, nomenclatural adjustments remain for the future