Estimation of the measurement uncertainty and practical suggestion for the description of the metrological traceability in clinical laboratories

Clinicians request a large part of measurements of biological quantities that clinical laboratories perform for diagnostic, prognostic or diseases monitoring purposes. Thus, laboratories need to provide patient’s results as reliable as possible. Metrological concepts like measurement uncertainty and metrological traceability allow to know the accuracy of these results and guarantee their comparability over time and space. Such is the importance of these two parameters that the estimation of measurement uncertainty and the knowledge of metrological traceability is required for clinical laboratories accredited by ISO 15189:2012. Despite there are many publications or guidelines to estimate the measurement uncertainty in clinical laboratories, it is not entirely clear what information and which formulae they should use to calculate it. On the other hand, unfortunately, there are a small number of clinical laboratories that know and describe the metrological traceability of their results, even though they are aware of the lack of comparability that currently exists for patient’s results. Thus, to try to facilitate the task of clinical laboratories, this review aims to provide a proposal to estimate the measurement uncertainty. Also, different suggestions are shown to describe the metrological traceability. Measurement uncertainty estimation is partially based on the ISO/TS 20914:2019 guideline, and the metrological traceability described using the ISO 17511:2020. Different biological quantities routinely measured in clinical laboratories are used to exemplify the proposal and suggestions.     

HOW MULTIMODALITY WORKS IN MATHEMATICAL ACTIVITY: YOUNG CHILDREN GRAPHING MOTION

This paper aims to contribute to discussions on the multimodal nature of cognition through an elaboration of the ways multimodal aspects of thinking are exploited by learners doing mathematics. Moving beyond the fact that multimodality occurs, this paper focuses on how it occurs, with particular attention drawn to the complex network of perceptual, bodily and imaginary experiences of students. Through an analysis of 2 selected episodes of the work of 1 primary school child learning to graph motion, the paper shows how the notion of blending spaces is central to understanding the mechanism of multimodality.     

Accidental digitoxin intoxication: an interplay between laboratory and clinical medicine

Introduction:

Two Italian adults arrived at the Emergency Department referring diarrhea, nausea and vomiting for 4 days; weakness, fatigue and visual hallucinations were also complained of. Patients reported the ingestion of some leaves of a plant, which they supposed to be “donkey ears”, a week before. Physical examination showed hypotension and bradycardia and ECG examination disclosed sinus rhythm and repolarization abnormalities (scooping of the ST-T complex) in both patients and a 2:1 AV block in the man.

Materials and methods:

Digoxin concentration was evaluated twice for each patient (at the admission and after 4 hours) by the automated immunoassay system ADVIA Centaur^®. Digitoxin concentration was evaluated by liquid chromatography-mass spectrometry (LC-MS/MS).

Results:

Despite clinical picture was suggestive of digitalis intoxication, digoxin levels were undetectable. Due to the more severe clinical picture, the male patient was treated with anti-digoxin antibodies (Digifab^®) achieving a good clinical improvement and remission of the AV block within two hours. Initial diagnosis was confirmed by LC-MS/MS showing high digitoxin concentrations, but digoxin was undetectable. Patients remained stable and 48 hours later were discharged from the hospital.

Conclusion:

Whereas digoxin determination frequently relies on monoclonal antibodies which do not cross-react to digitoxin, polyclonal antibodies constituting Digifab^® recognize a large spectrum of cardiac glycosides, including digitoxin. This report emphasizes the primary role of the clinical approach to patients in the emergency setting and how an active communication and a continuous sharing of professional experiences between Laboratory and Clinicians ensure an early and correct diagnosis.     

Geometrical effects in microfluidic-based microarrays for rapid, efficient single-cell capture of mammalian stem cells and plant cells

In this paper, a detailed numerical and experimental investigation into the optimisation of hydrodynamic micro-trapping arrays for high-throughput capture of single polystyrene (PS) microparticles and three different types of live cells at trapping times of 30 min or less is described. Four different trap geometries (triangular, square, conical, and elliptical) were investigated within three different device generations, in which device architecture, channel geometry, inter-trap spacing, trap size, and trap density were varied. Numerical simulation confirmed that (1) the calculated device dimensions permitted partitioned flow between the main channel and the trap channel, and further, preferential flow through the trap channel in the absence of any obstruction; (2) different trap shapes, all having the same dimensional parameters in terms of depth, trapping channel lengths and widths, main channel lengths and widths, produce contrasting streamline plots and that the interaction of the fluid with the different geometries can produce areas of stagnated flow or distorted field lines; and (3) that once trapped, any motion of the trapped particle or cell or a shift in its configuration within the trap can result in significant increases in pressures on the cell surface and variations in the shear stress distribution across the cell’s surface. Numerical outcomes were then validated experimentally in terms of the impact of these variations in device design elements on the percent occupancy of the trapping array (with one or more particles or cells) within these targeted short timeframes. Limitations on obtaining high trap occupancies in the devices were shown to be primarily a result of particle aggregation, channel clogging and the trap aperture size. These limitations could be overcome somewhat by optimisation of these device design elements and other operational variables, such as the average carrier fluid velocity. For example, for the 20 μm polystyrene microparticles, the number of filled traps increased from 32% to 42% during 5–10 min experiments in devices with smaller apertures. Similarly, a 40%–60% reduction in trapping channel size resulted in an increase in the amount of filled traps, from 0% to almost 90% in 10 min, for the human bone marrow derived mesenchymal stem cells, and 15%–85% in 15 min for the human embryonic stem cells. Last, a reduction of the average carrier fluid velocity by 50% resulted in an increase from 80% to 92% occupancy of single algae cells in traps. Interestingly, changes in the physical properties of the species being trapped also had a substantial impact, as regardless of the trap shape, higher percent occupancies were observed with cells compared to single PS microparticles in the same device, even though they are of approximately the same size. This investigation showed that in microfluidic single cell capture arrays, the trap shape that maximizes cell viability is not necessarily the most efficient for high-speed single cell capture. However, high-speed trapping configurations for delicate mammalian cells are possible but must be optimised for each cell type and designed principally in accordance with the trap size to cell size ratio.     

Newborns' face recognition: role of inner and outer facial features

Existing data indicate that newborns are able to recognize individual faces, but little is known about what perceptual cues drive this ability. The current study showed that either the inner or outer features of the face can act as sufficient cues for newborns' face recognition (Experiment 1), but the outer part of the face enjoys an advantage over the inner part (Experiment 2). Inversion of the face stimuli disrupted recognition when only the inner portion of the face was shown, but not when the whole face was fully visible or only the outer features were presented (Experiment 3). The results enhance our picture of what information newborns actually process and encode when they discriminate, learn, and recognize faces.     

Lessons learned from single service point implementations

Interest in consolidating service points within health sciences libraries continues. This article proposes a definition of a library single service point and mentions some notable examples in academic health sciences libraries. The experiences of two of these libraries are summarized and compared, and the advice culled from those experiences is shared. The advice is in the form of sharing lessons learned, answering six frequently asked questions about combining services and staff under a single service umbrella. The article offers insights for other library staff considering this type of service reorganization.     

Teachers’ perception of mobile edutainment for special needs learners: the Malaysian case

Study of Malaysian adoption of mobile learning (m-learning) is still in the early stages. However, there are numerous researchers in the country exploring the potential and application of m-learning in the Malaysian education system, including special education. A key question is whether teachers are prepared to incorporate mobile technology as part of their teaching tools or do teachers perceive mobile technology only as personal communication gadgets. This paper investigates teachers' perception of m-learning applications in special education classes. Interviews were conducted to collect related information on teachers' perceptions of m-learning in the selected schools. The teachers expressed that there are limited resources to cater to the attention of special needs learners and they believed edutainment technologies such as augmented reality, game-based educational software and animation projects could be the answer. The benefits and challenges of implementing blended learning for special education are also discussed. The paper concludes by summarising the current environment of m-learning in Malaysian special needs education, together with recommendations for future use of the technology.     

Conservation of stained glass windows with protective glazing: Main results from the European VIDRIO research programme

The methodology of protecting the European stained glass windows against environmental risk (e.g. meteorological factors, air pollution, microorganisms) by means of an external glazing is not new. In spite of many scientific studies carried out in the last 20 years, some questions were still up for discussion. The European VIDRIO (2002–2005) project gave an answer to these questions. The research carried out by the different project partners established a new multidisciplinary approach aimed at evaluating the efficiency of the protective glazing systems and their effects on stained glass windows conservation, and finally at assessing the most appropriate strategy to preserve stained glass windows. Scientific results showed that the so-called isothermal glazing (i.e. ventilation by the air coming from the inside of the building) protected efficiently the ancient stained glass window from environmental attack (i.e. rain, pollutants, condensation, thermal shocks) with very limited secondary effects. The scientific research highlighted that its efficiency was strongly related to the technical design of the protective system. In particular, the ventilation and the size of the interspace had to be carefully considered. The research developed within the VIDRIO project was turned into general recommendations to the owners and practitioners on the best practice for the stained glass windows future conservation.     

Sex,Love, and Risk-n-Responsibility: A Content Analysis of Entertainment Television

This study documents the extent of sexual content, including sexual health content, in scenes with and without expressions of love on network and cable television popular with emerging adults. Sexual talk and/or behavior was found in 20% of all television scenes coded across 53.5 hours of programming. One third of these scenes featured sex alongside expressions of love. An additional 10% of scenes suggested love but not sex. Coded as a separate category, 25% of analyzed scenes contained a passing joke or pun referencing sexual organs, making these nonspecific, comedic one-liners the predominant reference to sex in this sample. Beyond jokes, most of the sexual or loving talk in this sample consisted of expressing a romantic interest in someone; sex- and love-related behaviors largely consisted of kissing or flirting. Very few scenes specifically referenced sexual intercourse. Sexual health messages were also rare. The majority of scenes mentioning any health consequence (7% of analyzed scenes) concerned emotional heartache. One scene mentioned sexually transmitted infections; 12 of the nearly 2,600 scenes coded mentioned condoms or contraceptives. It is thus a challenging proposition to build upon existing sexual depictions on television to promote safe sex practices within sexual and loving contexts.     

Researching Researchers: Meeting Changing Researcher Needs in a Special Collections Environment

ABSTRACT

In the competitive Higher Education environment, it is no longer sufficient for special collections to rely on the “uniqueness” of a collection as its unique selling point—it must be supported by a service and strategic plan that is both proactive in anticipating the demands of future researchers and responsive to current researchers’ changing needs. Edinburgh University's Centre for Research Collections (CRC) is addressing this challenge for the first time in a coordinated manner, employing a suite of research methods that allow staff to take an evidence based approach to service development and strategic planning. These include ethnographic observation, structured surveys, object-based learning initiatives, comprehensive data interrogation, and active engagement with the University's academic schools. This article examines how these approaches have been utilized in the development of CRC services, and its benefit to long-term planning.