Tablet Keyboard Configuration Affects Performance, Discomfort and Task Difficulty for Thumb Typing in a Two-Handed Grip

When holding a tablet computer with two hands, the touch keyboard configuration imposes postural constraints on the user because of the need to simultaneously hold the device and type with the thumbs. Designers have provided users with several possible keyboard configurations (device orientation, keyboard layout and location). However, potential differences in performance, usability and postures among these configurations have not been explored. We hypothesize that (1) the narrower standard keyboard layout in the portrait orientation leads to lower self-reported discomfort and less reach than the landscape orientation; (2) a split keyboard layout results in better overall outcomes compared to the standard layout; and (3) the conventional bottom keyboard location leads to the best outcomes overall compared to other locations. A repeated measures laboratory experiment of 12 tablet owners measured typing speed, discomfort, task difficulty, and thumb/wrist joint postures using an active marker system during typing tasks for different combinations of device orientation (portrait and landscape), keyboard layout (standard and split), and keyboard location (bottom, middle, top). The narrower standard keyboard with the device in the portrait orientation was associated with less discomfort (least squares mean (and S.E.) 2.9±0.6) than the landscape orientation (4.5±0.7). Additionally, the split keyboard decreased the amount of reaching required by the thumb in the landscape orientation as defined by a reduced range of motion and less MCP extension, which may have led to reduced discomfort (2.7±0.6) compared to the standard layout (4.5±0.7). However, typing speed was greater for the standard layout (127±5 char./min.) compared to the split layout (113±4 char./min.) regardless of device orientation and keyboard location. Usage guidelines and designers can incorporate these findings to optimize keyboard design parameters and form factors that promote user performance and usability for thumb interaction

Evaluation of Etiquette Strategies to Adapt Feedback In Affect-Aware Tutoring

The purpose of this research is to investigate how to mitigate user frustration and improve task performancein the context of human-computer interaction (HCI). Even though user frustration plays a role in manyaspects of HCI and studies have looked into the consequences of frustration in various fields, the ways tomitigate frustration are less deeply examined. Once the system has the ability to understand and includeuser emotions as factors in HCI, the interaction between the user and the computer system could be adaptedif the computers are able to modify its behavior with users in appropriate ways to further joint performance.Specifically, a preliminary study was conducted to explore the task performance, motivation, andconfidence implications of changing the interaction between the human and the computer via differentetiquette strategies. Participants solved a total of twenty mathematics problems under different frustrationcondition with feedback given in different styles of etiquette. Changing etiquette strategies in tutoring ledto changes in performance, motivation, and confidence. The most effective etiquette strategies changedwhen users were frustrated. This work provides the foundation for the design of adaptive intelligenttutoring system based on etiquette strategies.Copyright Human Factors and Ergonomics Society 2016. Posted with permission.</div

Expertise, credibility of system forecasts and integration methods in judgmental demand forecasting

YesExpert knowledge elicitation lies at the core of judgmental forecasting—a domain that relies fully on the power of such knowledge and its integration into forecasting. Using experts in a demand forecasting framework, this work aims to compare the accuracy improvements and forecasting performances of three judgmental integration methods. To do this, a field study was conducted with 31 experts from four companies. The methods compared were the judgmental adjustment, the 50–50 combination, and the divide-and-conquer. Forecaster expertise, the credibility of system forecasts and the need to rectify system forecasts were also assessed, and mechanisms for performing this assessment were considered. When (a) a forecaster’s relative expertise was high, (b) the relative credibility of the system forecasts was low, and (c) the system forecasts had a strong need of correction, judgmental adjustment improved the accuracy relative to both the other integration methods and the system forecasts. Experts with higher levels of expertise showed higher adjustment frequencies. Our results suggest that judgmental adjustment promises to be valuable in the long term if adequate conditions of forecaster expertise and the credibility of system forecasts are met

Cooperation between COA6 and SCO2 in COX2 maturation during cytochrome c oxidase assembly links two mitochondrial cardiomyopathies.

Three mitochondria-encoded subunits form the catalytic core of cytochrome c oxidase, the terminal enzyme of the respiratory chain. COX1 and COX2 contain heme and copper redox centers, which are integrated during assembly of the enzyme. Defects in this process lead to an enzyme deficiency and manifest as mitochondrial disorders in humans. Here we demonstrate that COA6 is specifically required for COX2 biogenesis. Absence of COA6 leads to fast turnover of newly synthesized COX2 and a concomitant reduction in cytochrome c oxidase levels. COA6 interacts transiently with the copper-containing catalytic domain of newly synthesized COX2. Interestingly, similar to the copper metallochaperone SCO2, loss of COA6 causes cardiomyopathy in humans. We show that COA6 and SCO2 interact and that corresponding pathogenic mutations in each protein affect complex formation. Our analyses define COA6 as a constituent of the mitochondrial copper relay system, linking defects in COX2 metallation to cardiac cytochrome c oxidase deficiency

A method of measuring fingertip loading during keyboard use

A single keycap on a standard alphanumeric computer keyboard was instrumented with a piezoelectric load cell and the fingertip motion was recorded with a high-speed video motion analysis system. Contact force histories between the fingertip and the keycap were recorded while four subjects typed a standard text for five minutes. Each keystroke force history is characterized by three distinct phases: (I) keyswitch compression, (II) finger impact and (III) fingertip pulp compression and release. Each keystroke force history contained two relative maxima, one in phase II and one in phase III. The subject mean peak forces ranged from 1.6 to 5.3 N and the subject mean peak fingertip velocities ranged from 0.3 to 0.7 m/s. Motion analyses and force measurements suggest a ballistic model of finger motion during typing.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31426/1/0000344.pd

Beyond Robotic Wastelands of Time: Abandoned Pedagogical Agents and New Pedalled Pedagogies

Chatbots, known as pedagogical agents in educational settings, have a long history of use, beginning with Alan Turing’s work. Since then online chatbots have become embedded into the fabric of technology. Yet understandings of these technologies are inchoate and often untheorised. Integration of chatbots into educational settings over the past five years suggests an increase in interest in the ways in which chatbots might be adopted and adapted for teaching and learning. This article draws on historical literature and theories that to date have largely been ignored in order to (re)contextualise two studies that used responsive evaluation to examine the use of pedagogical agents in education. Findings suggest that emotional interactions with pedagogical agents are intrinsic to a user’s sense of trust, and that truthfulness, personalisation and emotional engagement are vital when using pedagogical agents to enhance online learning. Such findings need to be considered in the light of ways in which notions of learning are being redefined in the academy and the extent to which new literacies and new technologies are being pedalled as pedagogies in ways that undermine what higher education is, is for, and what learning means

Prediction of trapezius muscle activity and shoulder, head, neck, and torso postures during computer use: results of a field study

Background: Due to difficulties in performing direct measurements as an exposure assessment technique, evidence supporting an association between physical exposures such as neck and shoulder muscle activities and postures and musculoskeletal disorders during computer use is limited. Alternative exposure assessment techniques are needed. Methods: We predicted the median and range of amplitude (90th-10th percentiles) of trapezius muscle activity and the median and range of motion (90th-10th percentiles) of shoulder, head, neck, and torso postures based on two sets of parameters: the distribution of keyboard/mouse/idle activities only (“task-based” predictions), and a comprehensive set of task, questionnaire, workstation, and anthropometric parameters (“expanded model” predictions). We compared the task-based and expanded model predictions based on R2 values, root mean squared (RMS) errors, and relative RMS errors calculated compared to direct measurements. Results: The expanded model predictions of the median and range of amplitude of trapezius muscle activity had consistently better R2 values (range 0.40-0.55 compared to 0.00-0.06), RMS errors (range 2-3%MVC compared to 3-4%MVC), and relative RMS errors (range 10-14%MVC compared to 16-19%MVC) than the task-based predictions. The expanded model predictions of the median and range of amplitude of postures also had consistently better R2 values (range 0.22-0.58 compared to 0.00-0.35), RMS errors (range 2–14 degrees compared to 3–22 degrees), and relative RMS errors (range 9–21 degrees compared to 13–42 degrees) than the task-based predictions. Conclusions: The variation in physical exposures across users performing the same task is large, especially in comparison to the variation across tasks. Thus, expanded model predictions of physical exposures during computer use should be used rather than task-based predictions to improve exposure assessment for future epidemiological studies. Clinically, this finding also indicates that computer users will have differences in their physical exposures even when performing the same tasks

Learning at large conferences:from the 'sage on the stage' to contemporary models of learning

AimTo explore and evaluate the affordances of a flipped classroom model applied to a research paper session within the professional development opportunity of a large conference setting.MethodAuthors were invited to present their research papers in a flipped classroom presentation format at two large, multi-national conferences. Before the session, authors and moderators met online to clarify features of the session, and preparation of the material. The research material was then posted online before the conference, to allow access by meeting attendees. During the sessions, moderators encouraged the audience to actively participate. An evaluation form was collected from the audience at the end of each session.ResultsParticipants found the session valuable, and appreciated the opportunity to engage in a meaningful dialogue with colleagues. However, the majority of the audience did not access the materials in advance. Lack of time, or technology-related issues were mentioned as potential challenges to such format.ConclusionIn the context of a large conference, a 'flipped session' format can facilitate active learning and a participatory culture of inquiry. However, to change the nature of how individuals learn collaboratively at large conferences means a change in the culture of continuous professional learning

SAMMSON fosters cancer cell fitness by concertedly enhancing mitochondrial and cytosolic translation

Synchronization of mitochondrial and cytoplasmic translation rates is critical for the maintenance of cellular fitness, with cancer cells being especially vulnerable to translational uncoupling. Although alterations of cytosolic protein synthesis are common in human cancer, compensating mechanisms in mitochondrial translation remain elusive. Here we show that the malignant long non-coding RNA (lncRNA) SAMMSON promotes a balanced increase in ribosomal RNA (rRNA) maturation and protein synthesis in the cytosol and mitochondria by modulating the localization of CARF, an RNA-binding protein that sequesters the exo-ribonuclease XRN2 in the nucleoplasm, which under normal circumstances limits nucleolar rRNA maturation. SAMMSON interferes with XRN2 binding to CARF in the nucleus by favoring the formation of an aberrant cytoplasmic RNA-protein complex containing CARF and p32, a mitochondrial protein required for the processing of the mitochondrial rRNAs. These data highlight how a single oncogenic lncRNA can simultaneously modulate RNA-protein complex formation in two distinct cellular compartments to promote cell growth

C7orf30 specifically associates with the large subunit of the mitochondrial ribosome and is involved in translation

In a comparative genomics study for mitochondrial ribosome-associated proteins, we identified C7orf30, the human homolog of the plant protein iojap. Gene order conservation among bacteria and the observation that iojap orthologs cannot be transferred between bacterial species predict this protein to be associated with the mitochondrial ribosome. Here, we show colocalization of C7orf30 with the large subunit of the mitochondrial ribosome using isokinetic sucrose gradient and 2D Blue Native polyacrylamide gel electrophoresis (BN-PAGE) analysis. We co-purified C7orf30 with proteins of the large subunit, and not with proteins of the small subunit, supporting interaction that is specific to the large mitoribosomal complex. Consistent with this physical association, a mitochondrial translation assay reveals negative effects of C7orf30 siRNA knock-down on mitochondrial gene expression. Based on our data we propose that C7orf30 is involved in ribosomal large subunit function. Sequencing the gene in 35 patients with impaired mitochondrial translation did not reveal disease-causing mutations in C7orf30