Background
Storybooks are an effective tool for teaching complex scientific mechanisms to young children when presented in child-friendly, joint-attentional contexts like read-aloud sessions. ...However, static storybooks are limited in their ability to convey change across time and, relative to animated storybooks, are harder to disseminate to a wide audience. This study examined second graders’ abilities to learn the deeply counterintuitive concepts of adaptation and speciation from multi-day interventions centered around two storybooks about natural selection that were either read-aloud (static) or watched on a screen (animated). The storybook sequence was progressive and first explained—in counter-essentialist and non-teleological terms—how the relative distribution of a terrestrial mammal’s trait changed over time due to behavioral shifts in their primary food resource (adaptation, book 1). It then explained how–after a sub-population of this species became geographically isolated–they evolved into an entirely different aquatic species over many generations via selection on multiple foraging-relevant traits (speciation, book 2). The animated and static versions of the storybooks used the same text and illustrations, but while the animations lacked joint-attentional context, they more dynamically depicted successive reproductive generations. Storybook and animation presentations were interspersed with five parallel talk-aloud assessment interviews over three days.
Results
Findings revealed substantial learning from the read-aloud static storybook sequence. They also revealed substantial learning from the animation condition with patterns suggesting that the dynamic representations of change over time particularly scaffolded acquisition of the deeply counterintuitive idea that a species can evolve into an entirely different category of species by natural selection.
Conclusions
The results provide much-needed optimism in a context of increasing demands for scalable solutions to promote effective learning: animated storybooks are just as good (and may even be better) than static storybooks.
Pulsed flow fluidisation involves the use of either a relocating or intermittent gas stream flowing through a bed of particles, and produces a range of fluidisation effects dependent on the type and ...frequency of the pulsation. Pulsed flow has been shown in a range of studies to improve mixing and heat transfer, and reduce agglomeration. However these effects are dependent on the pulsation frequency, particle characteristics and other process conditions.
Research into pulsed flow fluidised beds has demonstrated a pattern for an improvement in heat and mass transfer rates, specifically in Group A and B particles, reduced slugging and channelling in wet or cohesive particles, and an improvement in the fluidisation of hard to fluidise materials such as Group C powders. In addition, reduced energy consumption from lower minimum fluidisation rates under pulsed flow further indicates a potentially significant efficiency improvement. These findings, however, highlight needs for correlations to be drawn between the effects studied and the pulsation method and frequencies applied.
Here, we present a comparison of continuous and pulsed flow fluidisation, and discuss effects such as minimum fluidisation velocity, bubble characteristics and bed expansion. Areas for future research have been identified in order to build a better picture of how pulsed flow frequencies and particle characteristics interact, aiding the development of this technology within industry.
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•A review of pulsed flow fluidisation•Comparison of continuous and pulsed flow fluidisation•Effects discussed: e.g. min. fluidisation velocity, bubble and bed characteristics•Areas for future research identified to aid development of the technology
Stillbirths: progress and unfinished business Frøen, J Frederik, Dr; Friberg, Ingrid K, PhD; Lawn, Joy E, Prof ...
The Lancet (British edition),
02/2016, Letnik:
387, Številka:
10018
Journal Article
Recenzirano
Odprti dostop
Summary This first paper of the Lancet Series on ending preventable stillbirths reviews progress in essential areas, identified in the 2011 call to action for stillbirth prevention, to inform the ...integrated post-2015 agenda for maternal and newborn health. Worldwide attention to babies who die in stillbirth is rapidly increasing, from integration within the new Global Strategy for Women's, Children's and Adolescents' Health, to country policies inspired by the Every Newborn Action Plan. Supportive new guidance and metrics including stillbirth as a core health indicator and measure of quality of care are emerging. Prenatal health is a crucial biological foundation to life-long health. A key priority is to integrate action for prenatal health within the continuum of care for maternal and newborn health. Still, specific actions for stillbirths are needed for advocacy, policy formulation, monitoring, and research, including improvement in the dearth of data for effective coverage of proven interventions for prenatal survival. Strong leadership is needed worldwide and in countries. Institutions with a mandate to lead global efforts for mothers and their babies must assert their leadership to reduce stillbirths by promoting healthy and safe pregnancies.
The higher education literature on feedback has generally explored spoken feedback delivered on a summative written assignment. In contrast, this study explores spoken feedback as part of the teacher ...- student dialogue in classroom interaction (i.e. feedback talk). Drawing on a discourse analysis approach we identified linguistic and rhetorical indicators of feedback talk and found a number of common patterns in six seminar events. Interviews with two teachers revealed a perception that feedback was an inherent part of the teaching and learning process and agreement on the significance of feedback talk in supporting relationships. We argue that a recognition and understanding of feedback talk can support the relational dimension of feedback literacy in the micro-moments of learning and teaching. We frame our discussion of feedback talk and teacher feedback literacy within the wider context of learning and teaching and call for a more holistic perspective on feedback.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Emerging data suggests a possible role for cysteamine as an adjunct treatment for pulmonary exacerbations of cystic fibrosis (CF) that continue to be a major clinical challenge. There are no studies ...investigating the use of cysteamine in pulmonary exacerbations of CF. This exploratory randomized clinical trial was conducted to answer the question: In future pivotal trials of cysteamine as an adjunct treatment in pulmonary exacerbations of CF, which candidate cysteamine dosing regimens should be tested and which are the most appropriate, clinically meaningful outcome measures to employ as endpoints?
Multicentre double-blind randomized clinical trial. Adults experiencing a pulmonary exacerbation of CF being treated with standard care that included aminoglycoside therapy were randomized equally to a concomitant 14-day course of placebo, or one of 5 dosing regimens of cysteamine. Outcomes were recorded on days 0, 7, 14 and 21 and included sputum bacterial load and the patient reported outcome measures (PROMs): Chronic Respiratory Infection Symptom Score (CRISS), the Cystic Fibrosis Questionnaire-Revised (CFQ-R); FEV1, blood leukocyte count, and inflammatory markers. Eighty nine participants in fifteen US and EU centres were randomized, 78 completed the 14-day treatment period. Cysteamine had no significant effect on sputum bacterial load, however technical difficulties limited interpretation. The most consistent findings were for cysteamine 450mg twice daily that had effects additional to that observed with placebo, with improved symptoms, CRISS additional 9.85 points (95% CI 0.02, 19.7) p = 0.05, reduced blood leukocyte count by 2.46x109 /l (95% CI 0.11, 4.80), p = 0.041 and reduced CRP by geometric mean 2.57 nmol/l (95% CI 0.15, 0.99), p = 0.049.
In this exploratory study cysteamine appeared to be safe and well-tolerated. Future pivotal trials investigating the utility of cysteamine in pulmonary exacerbations of CF need to include the cysteamine 450mg doses and CRISS and blood leukocyte count as outcome measures.
NCT03000348; www.clinicaltrials.gov.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The effects of pharmacological blood pressure lowering at normal or high-normal blood pressure ranges in people with or without pre-existing cardiovascular disease remains uncertain. We analysed ...individual participant data from randomised trials to investigate the effects of blood pressure lowering treatment on the risk of major cardiovascular events by baseline levels of systolic blood pressure.
We did a meta-analysis of individual participant-level data from 48 randomised trials of pharmacological blood pressure lowering medications versus placebo or other classes of blood pressure-lowering medications, or between more versus less intensive treatment regimens, which had at least 1000 persons-years of follow-up in each group. Trials exclusively done with participants with heart failure or short-term interventions in participants with acute myocardial infarction or other acute settings were excluded. Data from 51 studies published between 1972 and 2013 were obtained by the Blood Pressure Lowering Treatment Trialists' Collaboration (Oxford University, Oxford, UK). We pooled the data to investigate the stratified effects of blood pressure-lowering treatment in participants with and without prevalent cardiovascular disease (ie, any reports of stroke, myocardial infarction, or ischaemic heart disease before randomisation), overall and across seven systolic blood pressure categories (ranging from <120 to ≥170 mm Hg). The primary outcome was a major cardiovascular event (defined as a composite of fatal and non-fatal stroke, fatal or non-fatal myocardial infarction or ischaemic heart disease, or heart failure causing death or requiring admission to hospital), analysed as per intention to treat.
Data for 344 716 participants from 48 randomised clinical trials were available for this analysis. Pre-randomisation mean systolic/diastolic blood pressures were 146/84 mm Hg in participants with previous cardiovascular disease (n=157 728) and 157/89 mm Hg in participants without previous cardiovascular disease (n=186 988). There was substantial spread in participants' blood pressure at baseline, with 31 239 (19·8%) of participants with previous cardiovascular disease and 14 928 (8·0%) of individuals without previous cardiovascular disease having a systolic blood pressure of less than 130 mm Hg. The relative effects of blood pressure-lowering treatment were proportional to the intensity of systolic blood pressure reduction. After a median 4·15 years' follow-up (Q1–Q3 2·97–4·96), 42 324 participants (12·3%) had at least one major cardiovascular event. In participants without previous cardiovascular disease at baseline, the incidence rate for developing a major cardiovascular event per 1000 person-years was 31·9 (95% CI 31·3–32·5) in the comparator group and 25·9 (25·4–26·4) in the intervention group. In participants with previous cardiovascular disease at baseline, the corresponding rates were 39·7 (95% CI 39·0–40·5) and 36·0 (95% CI 35·3–36·7), in the comparator and intervention groups, respectively. Hazard ratios (HR) associated with a reduction of systolic blood pressure by 5 mm Hg for a major cardiovascular event were 0·91, 95% CI 0·89–0·94 for partipants without previous cardiovascular disease and 0·89, 0·86–0·92, for those with previous cardiovascular disease. In stratified analyses, there was no reliable evidence of heterogeneity of treatment effects on major cardiovascular events by baseline cardiovascular disease status or systolic blood pressure categories.
In this large-scale analysis of randomised trials, a 5 mm Hg reduction of systolic blood pressure reduced the risk of major cardiovascular events by about 10%, irrespective of previous diagnoses of cardiovascular disease, and even at normal or high–normal blood pressure values. These findings suggest that a fixed degree of pharmacological blood pressure lowering is similarly effective for primary and secondary prevention of major cardiovascular disease, even at blood pressure levels currently not considered for treatment. Physicians communicating the indication for blood pressure lowering treatment to their patients should emphasise its importance on reducing cardiovascular risk rather than focusing on blood pressure reduction itself.
British Heart Foundation, UK National Institute for Health Research, and Oxford Martin School.
ObjectiveThe Royal College of Obstetricians and Gynaecologists has advised that consolidation of birth centres, where reasonable, into birth centres of at least 6000 admissions per year should allow ...constant consultant presence. Currently, only 17% of mothers attend such birth centres. The objective of this work was to examine the feasibility of consolidation of birth centres, from the perspectives of birth centre size and travel times for mothers.DesignComputer-based optimisation.SettingHospital-based births.Population or sample1.91 million admissions in 2014–2016.MethodsA multiple-objective genetic algorithm.Main outcome measuresTravel time for mothers and size of birth centres.ResultsCurrently, with 161 birth centres, 17% of women attend a birth centre with at least 6000 admissions per year. We estimate that 95% of women have a travel time of 30 min or less. An example scenario, with 100 birth centres, could provide 75% of care in birth centres with at least 6000 admissions per year, with 95% of women travelling 35 min or less to their closest birth centre. Planning at local level leads to reduced ability to meet admission and travel time targets.ConclusionsWhile it seems unrealistic to have all births in birth centres with at least 6000 admissions per year, it appears realistic to increase the percentage of mothers attending this type of birth centre from 17% to about 75% while maintaining reasonable travel times. Planning at a local level leads to suboptimal solutions.
Lentiviral vectors are attractive delivery vehicles for cystic fibrosis gene therapy owing to their low immunogenicity and ability to integrate into the host cell genome, thereby producing long-term, ...stable gene expression. Nonetheless, repeat dosing may be required to increase initial expression levels, and/or boost levels when they wane. The primary aim of this study was to determine if repeat dosing of a VSV-G pseudotyped LV vector delivered into mouse lungs is more effective than a single dose. C57Bl/6 mouse lungs were conditioned with lysophosphatidylcholine, followed one-hour later by a LV vector carrying the luciferase reporter gene, using six different short-term (≤1 wk) and long-term (>1 wk) dosing schedules. Luciferase expression was quantified using bioluminescence imaging over 12 months. Most dosing schedules produced detectable bioluminescence over the 12-month period, but the shorter intervals (≤1 wk) produced higher levels of flux than the longest interval (five doses at least 1-month apart). Ex vivo lung analysis at 12 months showed that the estimated mean flux for the group that received two doses 1-week apart was significantly greater than the single dose group and the two groups that received doses over a period greater than 1-week. These results suggest that early consecutive multiple doses are more effective at improving gene expression in mouse lungs at 12 months, than longer repeat dosing intervals.
The generation of 3-nitrotyrosine, within proteins, is a post-translational modification resulting from oxidative or nitrative stress. It has been suggested that this modification could be used as a ...biomarker for inflammatory diseases. Despite the superiority of mass spectrometry-based determinations of nitrotyrosine, in a high-throughput clinical setting the measurement of nitrotyrosine by an enzyme-linked immunosorbent assay (ELISA) is likely to be more cost-effective. ELISAs offer an alternative means to detect nitrotyrosine, but many commercially available ELISAs are insufficiently sensitive to detect nitrotyrosine in healthy human serum. Here, we report the development, validation and clinical application of a novel electrochemiluminescence-based ELISA for nitrotyrosine which provides superior sensitivity (e.g. a 50-fold increase in sensitivity compared with one of the tested commercial colorimetric ELISAs). This nitrotyrosine ELISA has the following characteristics: a lower limit of quantitation of 0.04 nM nitrated albumin equivalents; intra- and inter-assay coefficients of variation of 6.5% and 11.3%, respectively; a mean recovery of 106 ± 3% and a mean linearity of 0.998 ± 0.001. Far higher nitration levels were measured in normal human blood cell populations when compared to plasma. Mass spectrometry was used to validate the new ELISA method. The analysis of the same set of chemically modified albumin samples using the ELISA method and mass spectrometry showed good agreement for the relative levels of nitration present in each sample. The assay was applied to serum samples from patients undergoing elective surgery which induces the human inflammatory response. Matched samples were collected before and one day after surgery. An increase in nitration was detected following surgery (median (IQR): 0.59 (0.00–1.34) and 0.97 (0.00–1.70) nitrotyrosine (fmol of nitrated albumin equivalents/mg protein) for pre- and post-surgery respectively. The reported assay is suitable for nitrotyrosine determination in patient serum samples, and may also be applicable as a means to determine oxidative stress in primary and cultured cell populations.
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•A highly sensitive ELISA for measurement of 3-nitrotyrosine has been developed.•The new ELISA was validated by mass spectrometry.•Nitration levels in human blood cell populations were higher than in plasma.•An increase in serum nitration after surgery was observed in patients.
Small-bodied marine fishes play an important role in the food web, feeding both larger fishes and seabirds. Often referred to as baitfishes, they concentrate seasonally in coastal areas in large, ...often heterospecific assemblages that are targeted by both commercial and recreational fishers. Given apparent declines in at least some of Bermuda's baitfish species over the past 40 years, it is useful to determine the species composition of baitfish assemblages, and how it varies among sites, in order to inform management. Using genetic barcoding of the Cytochrome c oxidase 1 gene (COI), we confirm species identity, assess intraspecific genetic diversity locally, and determine rates of broader genetic connectivity for baitfish assemblages in Bermuda. Species analyzed included
,
,
,
,
and
. Species identification based on molecular barcoding revealed some misidentification of individuals based solely on gross morphological characteristics, with an error rate of 11%, validating the usefulness of this approach. Interestingly, sequence results for the endemic Bermuda anchovy,
, were within 1% similarity to the more broadly distributed big-eye anchovy,
, and thus additional analyses are warranted to evaluate the genetic basis for endemism. Estimates of genetic diversity within and among baitfish assemblages in Bermuda were high, indicating high rates of local connectivity among sites for all species. As such, management should consider Bermuda's baitfish species as single, highly mixed populations. However, with the exception of
and the endemic
, significant genetic differentiation and population structure were found when comparing Bermuda's baitfish populations with those from other regions, suggesting limited gene flow between other regions and Bermuda for these species. Limited regional connectivity has implications for management, as strong genetic divergence suggests that populations in Bermuda are predominantly self-seeding and thus not likely to be replenished from distant populations. These results therefore support precautionary management of baitfish species in Bermuda.
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