87 research outputs found
Ultrastructural localization of calcium and Ca2+-ATPase activity in gonadotrops and stellate cells of the catfish pituitary
In the pituitary of the African catfish, Clarias gariepinus, calcium precipitates were ultrastructurally visualized with the oxalate-pyroantimonate procedure (OPP). The presence of calcium in these precipiates was validated with several methods, including "Electron Energy Loss Spectrometry" (EELS). In the OPP-treated tissue calcium precipitates were seen in a) non-secretory stellate cells and b) gonadotropic (GTH-) cells. In the latter the amount of precipitate is generally low, but stimulation of the gonadotropin release, either in vivo or in vitro, resulted in a considerable increase. This increase is discussed in relation to the role of calcium as second messenger in the GTH-cells. Ca2+-ATPase was exclusively represented in stellate cells and GTH-cells, its strongest activity associated with the plasma membrane and with the membranes of the endoplasmic reticulum. The localization of this enzyme is discussed in relation to its role in the regulation of the intracellular calcium concentration in the GTH-cells. The stellate cells are considered to be involved in the regulation of extracellular calcium concentrations in the pituitary
Embedding in Shawi narrations: A quantitative analysis of embedding in a post-colonial Amazonian indigenous society
In this article, we provide the first quantitative account of the frequent use of embedding in Shawi, a Kawapanan language spoken in Peruvian Northwestern Amazonia. We collected a corpus of ninety-two Frog Stories (Mayer 1969) from three different field sites in 2015 and 2016. Using the glossed corpus as our data, we conducted a generalised mixed model analysis, where we predicted the use of embedding with several macrosocial variables, such as gender, age, and education level. We show that bilingualism (Amazonian Spanish-Shawi) and education, mostly restricted by complex gender differences in Shawi communities, play a significant role in the establishment of linguistic preferences in narration. Moreover, we argue that the use of embedding reflects the impact of the mestizo1 society from the nineteenth century until today in Santa Maria de Cahuapanas, reshaping not only Shawi demographics but also linguistic practice
Classification and prioritization of usability problems using an augmented classification scheme
Various methods exist for conducting usability evaluation studies in health care. But although the methodology
is clear, no usability evaluation method provides a framework by which the usability reporting
activities are fully standardized. Despite the frequent use of forms to report the usability problems and
their context-information, this reporting is often hindered by information losses. This is due to the fact
that evaluatorsâ problem descriptions are based on individual judgments of what they find salient about
a usability problem at a certain moment in time. Moreover, usability problems are typically classified in
terms of their type, number, and severity. These classes are usually devised by the evaluator for the purpose
at hand and the used problem types often are not mutually exclusive, complete and distinct. Also the
impact of usability problems on the task outcome is usually not taken into account. Consequently, problem
descriptions are often vague and even when combined with their classification in type or severity
leave room for multiple interpretations when discussed with system designers afterwards. Correct interpretation
of these problem descriptions is then highly dependent upon the extent to which the evaluators
can retrieve relevant details from memory.
To remedy this situation a framework is needed guiding usability evaluators in high quality reporting
and unique classification of usability problems. Such a framework should allow the disclosure of the
underlying essence of problem causes, the severity rating and the classification of the impact of usability
problems on the task outcome. The User Action Framework (UAF) is an existing validated classification
framework that allows the unique classification of usability problems, but it does not include a severity
rating nor does it contain an assessment of the potential impact of usability flaws on the final task outcomes.
We therefore augmented the UAF with a severity rating based on Nielsenâs classification and
added a classification for expressing the potential impact of usability problems on final task outcomes.
Such an augmented scheme will provide the necessary information to system developers to understand
the essence of usability problems, to prioritize problems and to tackle them in a system redesign. To
investigate the feasibility of such an augmented scheme, it was applied to the results of usability studies
of a computerized physician order entry system (CPOE).
The evaluators classified the majority of the usability problems identically by use of the augmented
UAF. In addition it helped in differentiating problems that looked similar but yet affect the userâsystem
interaction and the task results differently and vice versa. This work is of value not only for system developers
but also for researchers who want to study the results of other usability evaluation studies, because
this scheme makes the results of usability studies comparable and easily retrievable
Success or failure in knowledge management systems: a universal issue
This paper takes a sociotechnical viewpoint of knowledge management system (KMS) implementation in organizations considering issues such as stakeholder disenfranchisement, lack of communication, and the low involvement of key personnel in system design asking whether KMS designers could learn from applying sociotechnical principles to their systems. The paper discusses design elements drawn from the sociotechnical principles essential for the success of IS and makes recommendations to increase the success of KMS
in organizations. It also provides guidelines derived from Cleggâs Principles (2000) for KMS designers to enhance their designs. Our data comes from the
application of a plurality of analysis methods on a large comprehensive global survey conducted from 2007 to 2011 of 1034 participants from 76 countries.
The survey covers a variety of organizations of all types and sizes from a comprehensive selection of economic sectors and industries. Our results showed
that users were not satisfied with the information and knowledge systems that they were being offered. In addition to multiple technology and usability issues,
there were human and organisational barriers that prevented the systems from being used to their full potential. We recommend that users of KMS are integrated
into the design team so that these usability and other barriers can be addressed during the feasibility stage as well as the actual design and implementation
phases
Capturing human intelligence for modelling cognitive-based clinical decision support agents
The success of intelligent agents in clinical care depends on the degree to which they represent and work with human decision makers. This is particularly important in the domain of clinical risk assessment where such agents either conduct the task of risk evaluation or support human clinicians with the task. This paper provides insights into how to understand and capture the cognitive processes used by clinicians when collecting the most important data about a personâs risks. It attempts to create some theoretical foundations for developing clinically justifiable and reliable decision support systems for initial risk screening. The idea is to direct an assessor to the most informative next question depending on what has already been asked using a mixture of probabilities and heuristics. The method was tested on anonymous mental health data collected by the GRiST risk and safety tool (www.egrist.org)
A human-centered design methodology to enhance the usability, human factors, and user experience of connected health systems: a three-phase methodology.
peer-reviewedDesign processes such as human-centered design, which involve the end user throughout the product development and testing process, can be crucial in ensuring that the product meets the needs and capabilities of the user, particularly in terms of safety and user experience. The structured and iterative nature of human-centered design can often present a challenge when design teams are faced with the necessary, rapid, product development life cycles associated with the competitive connected health industry.
We wanted to derive a structured methodology that followed the principles of human-centered design that would allow designers and developers to ensure that the needs of the user are taken into account throughout the design process, while maintaining a rapid pace of development. In this paper, we present the methodology and its rationale before outlining how it was applied to assess and enhance the usability, human factors, and user experience of a connected health system known as the Wireless Insole for Independent and Safe Elderly Living (WIISEL) system, a system designed to continuously assess fall risk by measuring gait and balance parameters associated with fall risk.
We derived a three-phase methodology. In Phase 1 we emphasized the construction of a use case document. This document can be used to detail the context of use of the system by utilizing storyboarding, paper prototypes, and mock-ups in conjunction with user interviews to gather insightful user feedback on different proposed concepts. In Phase 2 we emphasized the use of expert usability inspections such as heuristic evaluations and cognitive walkthroughs with small multidisciplinary groups to review the prototypes born out of the Phase 1 feedback. Finally, in Phase 3 we emphasized classical user testing with target end users, using various metrics to measure the user experience and improve the final prototypes.
We report a successful implementation of the methodology for the design and development of a system for detecting and predicting falls in older adults. We describe in detail what testing and evaluation activities we carried out to effectively test the system and overcome usability and human factors problems.
We feel this methodology can be applied to a wide variety of connected health devices and systems. We consider this a methodology that can be scaled to different-sized projects accordingly.PUBLISHEDpeer-reviewe
Overcoming Challenges to Inclusive User-based Testing of Health Information Technology with Vulnerable Older Adults: Recommendations from a Human Factors Engineering Expert Inquiry
Objectives: Involving representative users in usability testing of health information technology (HIT) is central to user-centered design. However, (vulnerable) older adults as representative users have unique requirements. Aging processes may affect physical capabilities and cognitive skills, which can hamper testing with this demographic and may require special attention and revised protocols. This study was performed to provide expert-based recommendations for HIT user-testing with (vulnerable) older adults to support inclusive HIT design and evaluation.
Methods: First, we conducted a structured workshop with ten experts in HIT implementation and research, recruited through purposeful sampling, to generate insights into how characteristics of older adults may influence user-testing. Next, five Human Factor researchers experienced in HIT user-testing with (vulnerable) older adults validated the results and provided additional textual insights to gain consensus on the most important recommendations. A thematic analysis was performed on the resulting inquiries. Applied codes were based on the User-Centered Design framework.
Results: The analysis resulted in nine recommendations for user-testing of HIT with older adults, divided into three main themes: (1) empathetic approach and trust-building, (2) new requirements for testing and study design, and (3) adjustments to usability evaluation methods. For each theme a checklist of relevant items to follow-up on the recommendation is provided.
Conclusions: The recommendations generated through expert inquiry contribute to more effective usability testing of HIT with older adults. This provides an important step towards improved accessibility of HIT amongst older adults through inclusive user-centered design
Quality of human-computer interaction - results of a national usability survey of hospital-IT in Germany
<p>Abstract</p> <p>Background</p> <p>Due to the increasing functionality of medical information systems, it is hard to imagine day to day work in hospitals without IT support. Therefore, the design of dialogues between humans and information systems is one of the most important issues to be addressed in health care. This survey presents an analysis of the current quality level of human-computer interaction of healthcare-IT in German hospitals, focused on the users' point of view.</p> <p>Methods</p> <p>To evaluate the usability of clinical-IT according to the design principles of EN ISO 9241-10 the IsoMetrics Inventory, an assessment tool, was used. The focus of this paper has been put on suitability for task, training effort and conformity with user expectations, differentiated by information systems. Effectiveness has been evaluated with the focus on interoperability and functionality of different IT systems.</p> <p>Results</p> <p>4521 persons from 371 hospitals visited the start page of the study, while 1003 persons from 158 hospitals completed the questionnaire. The results show relevant variations between different information systems.</p> <p>Conclusions</p> <p>Specialised information systems with defined functionality received better assessments than clinical information systems in general. This could be attributed to the improved customisation of these specialised systems for specific working environments. The results can be used as reference data for evaluation and benchmarking of human computer engineering in clinical health IT context for future studies.</p
- âŠ