This work investigates the feasibility of yeast-based impedance measurements for retrospective dosimetry applications. The local environment around yeast cells in a previously developed film-badge ...was modeled using Geant4. A greater dose response was observed when yeast cells were surrounded by an aluminum-polymer structure, which acted as a conversion layer. Bench-top experiments were conducted using a jar-based dosimeter design that directly combined a finely-ground aluminum conversion medium with yeast powder. It was shown when irradiated in the presence of aluminum grains, yeast cells yielded a higher impedance signal, thereby indicating greater radiation-induced damage. Finally, in separate irradiation experiments, lead and aluminum sheets were placed behind yeast samples and the dosimeters were irradiated to 1 Gy. A 2-fold increase in the impedance signal was shown when samples were positioned in close contact with the lead sheet compared to the aluminum sheet. In all experiments, it was shown that the local environment significantly influences radiative energy deposition in yeast cells.
•Yeast-based impedance biodosimetry is presented as a retrospective dosimetry technique.•The impact of the local environment around yeast cells in biodosimetry measurements is discussed.•Sample preparation methods and a measurement protocol in evaluating the impedance response of irradiated yeast samples is presented.
This study attempted to optimize a computer-based learning environment designed to teach learners how to solve word problems by incorporating an animated pedagogical agent. The agent was programmed ...to deliver instructional explanations either textually or aurally, while simultaneously using gaze and gesture to direct the learners to focus their attention on the relevant part of the example. In Experiment 1, learners presented with an agent delivering explanations aurally (voice plus agent) outperformed their control peers on measures of transfer. In Experiment 2, learners in the voice-plus-agent condition outperformed their peers presented with textual explanations on a variety of measures, including far transfer. In sum, an animated agent programmed to deliver instructions aurally can help optimize learning from examples.
There exist few empirical rules for the effects of introduced species, reflecting the context‐dependent nature of biological invasions. A promising approach toward developing generalizations is to ...explore hypotheses that incorporate characteristics of both the invader and the recipient system. We present the first general test of the hypothesis that an invader's impact is determined by the system's evolutionary experience with similar species. Through a meta‐analysis, we compared the taxonomic distinctiveness of high‐ and low‐impact invaders in several aquatic systems. We find that high‐impact invaders (i.e. those that displace native species) are more likely to belong to genera not already present in the system.
•A thorough review on screen-printed silver/silver chloride reference electrodes.•Advancements and improvements on the development of a more reliable, solid-state reference electrode.•Description of ...various approaches adopted over the years for performance optimization of silver/silver chloride reference electrodes.
The screen-printed (SP), reference electrode (RE) has been shown to be a crucial element of potentiometric sensors but it is also the stumbling block for reliable and accurate SP sensors. The easiest, most common and most environmentally friendly, type of RE is the Silver/Silver Chloride (Ag/AgCl) RE. Unfortunately, until now the only reliable RE of this kind is the conventional, liquid or gel-filled type. However, for most environmental and soil applications the use of the conventional RE is not an option, which raises the demand for a robust, rugged and low-cost version to replace the conventional RE. This paper presents a review of the various attempts to produce reliable, SP, Ag/AgCl REs, and explain why almost all of them never reach the commercialisation stage. The paper provides an overview of the main challenges that need to be overcome, details of the electrode’s construction, an analytical comparison of their performance in terms of chloride susceptibility, cross-sensitivity and lifetime, and their suitability in different applications depending on their performance characteristics.
Although research has demonstrated that successively fading or successively removing more and more worked-out solution steps as learners transition from relying on examples to independent problem ...solving reliably fosters performance on near-transfer tasks-relative to example-problem pairs-this effect is not reliable on far-transfer tasks. To address this, the authors combined fading with the introduction of prompts designed to encourage learners to identify the underlying principle illustrated in each worked-out solution step. Across 2 experiments, this combination produced medium to large effects on near and far transfer without requiring additional time on task. Thus, the instructional procedure is highly recommendable because it (a) is relatively straightforward to implement, (b) does not prolong learning time, and (c) fosters both near- and far-transfer performance.
The association between alcohol consumption and risk of gout has been suspected since ancient times, but has not been prospectively confirmed. Additionally, potential differences in risk of gout ...posed by different alcoholic beverages have not been assessed.
Over 12 years (1986–98) we used biennial questionnaires to investigate the relation between alcohol consumption and risk of incident gout in 47 150 male participants with no history of gout at baseline. We used a supplementary questionnaire to ascertain whether reported cases of gout met the American College of Rheumatology survey gout criteria.
We documented 730 confirmed incident cases of gout. Compared with men who did not drink alcohol, the multivariate relative risk (RR) of gout was 1·32 (95% CI 0·99–1·75) for alcohol consumption 10·0–14·9 g/day, 1·49 (1·14–1·94) for 15·0–29·9 g/day, 1·96 (1·48–2·60) for 30·0–49·9 g/day, and 2·53 (1·73–3·70) for ≥50 g/day (p for trend <0·0001). Beer consumption showed the strongest independent association with the risk of gout (multivariate RR per 12-oz serving per day 1·49; 95% CI 1·32–1·70). Consumption of spirits was also significantly associated with gout (multivariate RR per drink or shot per day 1·15; 95% CI 1·04–1·28); however, wine consumption was not (multivariate RR per 4-oz serving per day 1·04; 95% CI 0·88–1·22).
Alcohol intake is strongly associated with an increased risk of gout. This risk varies substantially according to type of alcoholic beverage: beer confers a larger risk than spirits, whereas moderate wine drinking does not increase the risk.
Background
Biased interpretations of ambiguous bodily threat situations characterize youth with chronic pain, and have been associated with functional disability for this population. Despite ...predictions by the fear‐avoidance model of chronic pain, that fear and avoidance of pain explain the association between threat perceptions and disability, this has not yet been explored in youth with chronic pain. This study aimed to address this gap by investigating these proposed relationships, in addition to the association between bodily threat interpretations and daily aspects of disability (as well as social, and emotional impairments).
Method
Sixty‐eight adolescents aged 11–18 years old with a clinical diagnosis of chronic pain completed an extended version of the Adolescent Interpretations of Bodily Threat task to assess interpretations of bodily and social threat situations, alongside measures of disability and fear and avoidance of pain.
Results
Using mediation analysis, fear and avoidance of pain statistically accounted for the relationship between negative bodily threat interpretations and functional disability. Significant associations were also demonstrated between negative bodily threat interpretations and adolescent‐reported impairments in daily, emotional and social impairments. Data revealed a significant relationship between negative social interpretations and daily functional disability.
Conclusions
Findings indicate the clinical relevance of bodily and social threat interpretations, and fear and avoidance of pain, for this population and raise further questions regarding the content‐specificity of threat interpretations.
Significance
Psychological theories of pain‐associated impact and disability point to fear and avoidance of pain, as well as information‐processing biases. Here, we present novel data showing the clinical relevance of bodily and social threat interpretations in explaining pain‐related disability amongst youth with chronic pain, potentially by shaping fear and avoidance of pain. Longitudinal designs will be required to assess these temporally sensitive mediation pathways.
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