225 research outputs found
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Chemistry and the Worm: Caenorhabditis elegans as a Platform for Integrating Chemical and Biological Research
This Review discusses the potential usefulness of the worm Caenorhabditis elegans as a model organism for chemists interested in studying living systems. C. elegans, a 1 mm long roundworm, is a popular model organism in almost all areas of modern biology. The worm has several features that make it attractive for biology: it is small (<1000 cells), transparent, and genetically tractable. Despite its simplicity, the worm exhibits complex phenotypes associated with multicellularity: the worm has differentiated cells and organs, it ages and has a well-defined lifespan, and it is capable of learning and remembering. This Review argues that the balance between simplicity and complexity in the worm will make it a useful tool in determining the relationship between molecular-scale phenomena and organism-level phenomena, such as aging, behavior, cognition, and disease. Following an introduction to worm biology, the Review provides examples of current research with C. elegans that is chemically relevant. It also describes tools—biological, chemical, and physical—that are available to researchers studying the worm.Chemistry and Chemical Biolog
Incorporation of prefabricated screw, pneumatic, and solenoid valves into microfluidic devices
This paper describes a method for prefabricating screw, pneumatic, and solenoid valves and embedding them in microfluidic devices. This method of prefabrication and embedding is simple, requires no advanced fabrication, and is compatible with soft lithography. Because prefabrication allows many identical valves to be made at one time, the performance across different valves made in the same manner is reproducible. In addition, the performance of a single valve is reproducible over many cycles of opening and closing: an embedded solenoid valve opened and closed a microfluidic channel more than 100,000 times with no apparent deterioration in its function. It was possible to combine all three types of prefabricated valves in a single microfluidic device to control chemical gradients in a microfluidic channel temporally and spatially
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Computerised speechreading training for deaf children: A randomised controlled trial
Purpose: We developed and evaluated in a randomised controlled triala computerised speechreading training programme to determine a) whether it is possible to train speechreading in deaf children and b) whether speechreading training results in improvements in phonological and reading skills.Previous studies indicate a relationship between speechreading and reading skill and further suggest this relationshipmay be mediated by improved phonological representations. This is important since many deaf children find learning to read to be very challenging.
Method: Sixty-six deaf 5-7 year olds were randomised into speechreading and maths training arms. Each training programme was comprised of10 minutesessionsa day, 4 days a week for 12 weeks. Children were assessed on a battery of language and literacy measures before training, immediately after training, 3 months and 10 months after training.
Results: We found no significant benefits for participants who completed the speechreading training, compared to those who completed the maths training, on the speechreading primary outcome measure. However, significantly greater gains were observed in the speechreading training group on one of the secondary measures of speechreading. There was also some evidence of beneficial effects of the speechreading training on phonological representations, however these effects were weaker. No benefits were seen toword reading.
Conclusions: Speechreading skill is trainable in deaf children. However, to support early reading, training may need to be longer or embedded in a broader literacy programme. Nevertheless, a training tool that can improve speechreading is likely to be of great interest to professionals working with deaf children
Investigating digital video applications in distance learning
The paper gives a brief overview of the use of digital video in distance education, the background to The Open University's Digital Video Applications (DiVA) Project, the contexts in which the Digital Video Library system is being used and some evaluation findings. Through DiVA, the university is investigating how it can use its video assets effectively, to support reuse of existing materials in course production. The project team is also evaluating student use of the system. The paper reports on an observation study which revealed several usability issues and stakeholders' opinions about potential uses of the DiVA system. This is followed by findings from an evaluation of student use of the system at a residential school and its use as part of an online learning activity undertaken by students accessing the system remotely. Evaluation findings to date indicate some quality and workload issues but they also show opportunities that come to light when using the DiVA system
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Lifespan-on-a-Chip: Microfluidic Chambers for Performing Lifelong Observation of C. elegans
This article describes the fabrication of a microfluidic device for the liquid culture of many individual nematode worms (Caenorhabditis elegans) in separate chambers. Each chamber houses a single worm from the fourth larval stage until death, and enables examination of a population of individual worms for their entire adult lifespans. Adjacent to the chambers, the device includes microfluidic worm clamps, which enable periodic, temporary immobilization of each worm. The device made it possible to track changes in body size and locomotion in individual worms throughout their lifespans. This ability to perform longitudinal measurements within the device enabled the identification of age-related phenotypic changes that correlate with lifespan in C. elegans.Chemistry and Chemical Biolog
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On the journey to impact: developing an impact strategy plan for the PRIME project
The Protecting Minority Ethnic Communities Online (PRIME) project is a UKRI-funded transdisciplinary, cross-sectoral, and cross-institutional project involving a consortium of Cranfield University, Universities of Glasgow and York, The Open University and community organisations, led by Heriot Watt University. Launched in April 2022, the 36-month project will increase understanding of minority ethnic communities’ experiences of online services; capacity for responding to these communities; and how online harm can be mitigated for these communities.
The PRIME project has a dedicated impact and dissemination work package led by The Open University. An approach we took in PRIME is to undertake impact and dissemination work throughout the project’s lifetime rather than focus on impact in the final stages of the project.
In this session we discussed the steps we had taken to setting up an impact plan for PRIME, from the stakeholder analysis to developing an impact strategy. We covered the resources we found useful in the early stages of our impact work, how we had utilized participatory approaches to inform our impact plan, and the challenges we had faced so far in coordinating the impact work across this large-scale project, involving both academic and non-academic stakeholders
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Speechreading ability is related to phonological awareness and single-word reading in both deaf and hearing children
Purpose. Speechreading (lipreading) is a correlate of reading ability in both deaf and hearing children. We investigated whether the relationship between speechreading and single-word reading is mediated by phonological awareness in deaf and hearing children.
Method. In two separate studies, 66 deaf children and 138 hearing children, aged 5–8 years old, were assessed on measures of speechreading, phonological awareness, and single-word reading. We assessed the concurrent relationships between latent variables measuring speechreading, phonological awareness, and single-word reading.
Results. In both deaf and hearing children, there was a strong relationship between speechreading and single-word reading, which was fully mediated by phonological awareness.
Conclusions. These results are consistent with ideas from previous studies that visual speech information contributes to the development of phonological representations in both deaf and hearing children, which, in turn, support learning to read. Future longitudinal and training studies are required to establish whether these relationships reflect causal effects
Classifying Alternative Approaches for Simple Drug Possession: A Two-Level Taxonomy
Background: Increasing international attention is being given to alternative
measures to criminalization for the possession of illicit drug. Such schemes are heterogeneous and a clear conceptual framework for their discussion and analysis is lacking.
Aim: To present a conceptually informed, empirically based taxonomy for the
classification of alternative measures to decriminalization for the possession of drugs.
Methods: The research uses qualitative comparative analysis (QCA) of
existing alternative measures. It proceeds from analysis of existing distinctions between and classifications of alternative measures. It uses data from a realist review of alternative measures in nine countries (Australia, Czech Republic, Denmark, Germany, Jamaica, Netherland, Portugal, UK and USA) to derive three dimensions of comparison (whether they: are de jure or de facto; involve diversion to an educative, therapeutic of social service; involve the use of civil/administrative sanctions). A QCA truth table using data from twenty-six schemes in the nine countries is used to identify types in the taxonomy. The types are grouped - using pragmatic reduction informed by Boolean minimization across a smaller number of classes in order to create a two-level taxonomy.
Results: The resulting taxonomy contains six types of alternative measures: depenalization; de facto diversion; de jure diversion; decriminalization with diversion and civil sanctions, decriminalization with civil sanctions; and decriminalization with no sanctions. The six types fall into three classes: depenalization; diversion; and decriminalization. It is possible to classify emerging alternatives into this new taxonomy.
Conclusion: Conceptually informed empirical observation of cases enables
the construction of a two-level taxonomy of alternative measures to criminalization for the simple possession of drugs. This may facilitate clearer and better-informed discussion of alternatives to criminalization for drug possession
Lifespan-on-a-chip: microfluidic chambers for performing lifelong observation of C. elegans
This article describes the fabrication of a microfluidic device for the liquid culture of many individual nematode worms (Caenorhabditis elegans) in separate chambers. Each chamber houses a single worm from the fourth larval stage until death, and enables examination of a population of individual worms for their entire adult lifespans. Adjacent to the chambers, the device includes microfluidic worm clamps, which enable periodic, temporary immobilization of each worm. The device made it possible to track changes in body size and locomotion in individual worms throughout their lifespans. This ability to perform longitudinal measurements within the device enabled the identification of age-related phenotypic changes that correlate with lifespan in C. elegans
Comparing alternating pressure mattresses and high-specification foam mattresses to prevent pressure ulcers in high-risk patients: the PRESSURE 2 RCT
Background:
Pressure ulcers (PUs) are a burden to patients, carers and health-care providers. Specialist mattresses minimise the intensity and duration of pressure on vulnerable skin sites in at-risk patients.
Primary objective:
Time to developing a new PU of category ≥ 2 in patients using an alternating pressure mattress (APM) compared with a high-specification foam mattress (HSFM).
Design:
A multicentre, Phase III, open, prospective, planned as an adaptive double-triangular group sequential, parallel-group, randomised controlled trial with an a priori sample size of 2954 participants. Randomisation used minimisation (incorporating a random element).
Setting:
The trial was set in 42 secondary and community inpatient facilities in the UK.
Participants:
Adult inpatients with evidence of acute illness and at a high risk of PU development.
Interventions and follow-up:
APM or HSFM – the treatment phase lasted a maximum of 60 days; the final 30 days were post-treatment follow-up.
Main outcome measures:
Time to event.
Results:
From August 2013 to November 2016, 2029 participants were randomised to receive either APM (n = 1016) or HSFM (n = 1013). Primary end point – 30-day final follow-up: of the 2029 participants in the intention-to-treat population, 160 (7.9%) developed a new PU of category ≥ 2. There was insufficient evidence of a difference between groups for time to new PU of category ≥ 2 [Fine and Gray model HR 0.76, 95% confidence interval (CI) 0.56 to 1.04; exact p-value of 0.0890 and 2% absolute difference]. Treatment phase sensitivity analysis: 132 (6.5%) participants developed a new PU of category ≥ 2 between randomisation and end of treatment phase. There was a statistically significant difference in the treatment phase time-to-event sensitivity analysis (Fine and Gray model HR 0.66, 95% CI 0.46 to 0.93; p = 0.0176 and 2.6% absolute difference). Secondary end points – 30-day final follow-up: new PUs of category ≥ 1 developed in 350 (17.2%) participants, with no evidence of a difference between mattress groups in time to PU development, (Fine and Gray model HR 0.83, 95% CI 0.67 to 1.02; p-value = 0.0733 and absolute difference 3.1%). New PUs of category ≥ 3 developed in 32 (1.6%) participants with insufficient evidence of a difference between mattress groups in time to PU development (Fine and Gray model HR 0.81, 95% CI 0.40 to 1.62; p = 0.5530 and absolute difference 0.4%). Of the 145 pre-existing PUs of category 2, 89 (61.4%) healed – there was insufficient evidence of a difference in time to healing (Fine and Gray model HR 1.12, 95% CI 0.74 to 1.68; p = 0.6122 and absolute difference 2.9%). Health economics – the within-trial and long-term analysis showed APM to be cost-effective compared with HSFM; however, the difference in costs models are small and the quality-adjusted life-year gains are very small. There were no safety concerns. Blinded photography substudy – the reliability of central blinded review compared with clinical assessment for PUs of category ≥ 2 was ‘very good’ (kappa statistic 0.82, prevalence- and bias-adjusted kappa 0.82). Quality-of-life substudy – the Pressure Ulcer Quality of Life – Prevention (PU-QoL-P) instrument meets the established criteria for reliability, construct validity and responsiveness.
Limitations:
A lower than anticipated event rate.
Conclusions:
In acutely ill inpatients who are bedfast/chairfast and/or have a category 1 PU and/or localised skin pain, APMs confer a small treatment phase benefit that is diminished over time. Overall, the APM patient compliance, very low PU incidence rate observed and small differences between mattresses indicate the need for improved indicators for targeting of APMs and individualised decision-making. Decisions should take into account skin status, patient preferences (movement ability and rehabilitation needs) and the presence of factors that may be potentially modifiable through APM allocation, including being completely immobile, having nutritional deficits, lacking capacity and/or having altered skin/category 1 PU.
Future work:
Explore the relationship between mental capacity, levels of independent movement, repositioning and PU development. Explore ‘what works for whom and in what circumstances’.
Trial registration:
Current Controlled Trials ISRCTN01151335.
Funding:
This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 52. See the NIHR Journals Library website for further project information
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