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Design and characterization of a 3D-printed pneumatically-driven bistable valve with tunable characteristics
No full textAlthough research studies in pneumatic soft robots develop rapidly, most pneumatic actuators are still controlled by rigid valves and conventional electronics. The existence of these rigid, electronic components sacrifices the compliance and adaptability of soft robots. Current electronics-free valve designs based on soft materials are facing challenges in behaviour consistency, design flexibility, and fabrication complexity. Taking advantages of soft material 3D printing, this letter presents a new design of a bi-stable pneumatic valve, which utilises two soft, pneumatically-driven, and symmetrically-oriented conical shells with structural bistability to stabilise and regulate the airflow. The critical pressure required to operate the valve can be adjusted by changing the design features of the soft bi-stable structure. Multi-material printing simplifies the valve fabrication, enhances the flexibility in design feature optimisations, and improves the system repeatability. In this work, both a theoretical model and physical experiments are introduced to examine the relationships between the critical operating pressure and the key design features. Results with valve characteristic tuning via material stiffness changing show better effectiveness compared to the change of geometry design features (demonstrated largest tunable critical pressure range from 15.3 to 65.2 kPa and fastest response time ≤1.8s )
System architecture for "Support through Mobile Messaging and Digital Health Technology for Diabetes" (SuMMiT-D): Design and performance in pilot and randomized controlled feasibility studies
No full textBackground:
Diabetes is a highly prevalent long-term condition with high morbidity and mortality rates. People with diabetes commonly worry about their diabetes medicines and do not always take them regularly as prescribed. This can lead to poor diabetes control. The Support Through Mobile Messaging and Digital Health Technology for Diabetes (SuMMiT-D) study aims to deliver brief messages as tailored interventions to support people with type 2 diabetes in better use of their diabetes medicines and to improve treatment adherence and health outcomes.
Objective:
This paper describes the overall architecture of a tailored intervention delivery system used in the pilot and randomized controlled feasibility studies of SuMMiT-D and reports its performance.
Methods:
The SuMMiT-D system includes several platforms and resources to recruit participants and deliver messages as tailored interventions. Its core component is called the clinical system and is responsible for interacting with the participants by receiving and sending SMS text messages from and to them. The personalization and tailoring of brief messages for each participant is based on a list of built-in commands that they can use.
Results:
For the pilot study, a total of 48 participants were recruited; they had a median age of 64 years (first quartile, third quartile [Q1, Q3: 54.5, 69]). For the feasibility study, a total of 209 participants were recruited and randomly assigned to either the control or intervention group; they had a median age of 65 years (Q1, Q3: 56, 71), with 41.1% (86/209) being female. The participants used the SuMMiT-D system for up to 6 months (26 weeks) and had a wide range of different interactions with the SuMMiT-D system while tailored interventions were being delivered. For both studies, we had low withdrawal rates: only 4.2% and 5.3% for the pilot and feasibility studies, respectively.
Conclusions:
A system was developed to successfully deliver brief messages as tailored health interventions to more than 250 people with type 2 diabetes via SMS text messages. On the basis of the low withdrawal rates and positive feedback received, it can be inferred that the SuMMiT-D system is robust, user-friendly, useful, and positive for most participants. From the two studies, we found that online recruitment was more efficient than recruitment via postal mail; a regular SMS text reminder (eg, every 4 weeks) can potentially increase the participants’ interactions with the system.
Trial Registration:
ISRCTN Registry ISRCTN13404264; http://www.isrctn.com/ISRCTN1340426
Prevalence and characteristics of illegal jaguar trade in north-western Bolivia
No full textRecent seizures of jaguar body parts in Bolivia have prompted concern about illegal trade to China, but a detailed understanding of this emerging trade continues to be lacking. We interviewed 1107 people in a rural area implicated in the trade, using direct and indirect questions through the Ballot Box Method (BBM) to explore the prevalence and characteristics of the illegal jaguar trade and its links to foreign demand. Jaguar trade is a common, and mostly non-sensitive practice; 46% of respondents reported some involvement over the past 5 years. The most common behaviour was owning jaguar body parts, such as skins, fat and teeth for decorative, medicinal, and cultural purposes. The most mentioned traders were Bolivian, followed by traders of Asian descent. However, regression analysis shows that the presence of traders of European descent was more significantly and positively associated with jaguar trade related behaviours, ahead of Asian descent and regional traders. Overall, jaguar trade in Bolivia has more diverse actors and drivers than seizures may suggest. Therefore, conservation interventions, in addition to targeting demand from Chinese wildlife markets, should address other foreign and domestic markets and trade chains
Synthesis of ultra-high molecular weight poly(ethylene)-co-(1-hexene) copolymers through high-throughput catalyst screening
No full textA family of permethylindenyl titanium constrained geometry complexes, Me2SB(R′N,3-RI*)TiX2 ((3-R-η5-C9Me5)Me2Si(R′TiX2)), supported on solid polymethylaluminoxane (sMAO) are investigated as slurry-phase catalysts for ethylene/H2 homopolymerisation and ethylene/1-hexene copolymerisation by high-throughput catalyst screening. Me2SB(tBuN,I*)TiCl2 supported on sMAO [sMAO-Me2SB(tBuN,I*)TiCl2] is responsive to small quantities of H2 (<1.6%), maintaining high polymerisation activities (up to 4900 kgPE molTi−1 h−1 bar−1) and yielding polyethylenes with significantly decreased molecular weight (Mw) (from 2700 to 41 kDa with 1.6% H2). In slurry-phase ethylene/1-hexene copolymerisation studies, a decrease in polymerisation activity and polymer molecular weights compared to ethylene homopolymerisation is observed. Compared to many solid supported system, these complexes all display high 1-hexene incorporation levels up to a maximum incorporation of 14.2 mol% for sMAO-Me2SB(iPrN,I*)TiCl2). We observe a proportionate increase in 1-hexene incorporation with concentration, highlighting the ability of these catalysts to controllably tune the amount of 1-hexene incorporated into the polymer chain to produce linear low-density polyethylene (LLDPE) materials
The impact of mass shootings on attitudes toward gun restrictions
No full textIs the American public more likely to favor stricter gun legislation in the aftermath of deadly mass shootings? The authors leverage the occurrence of several mass shootings during multiple survey waves of the General Social Survey between 1987 and 2018 to examine whether exposure to a mass shooting sways public opinion on gun legislation. The results reveal that mass shootings increase support for stricter gun permits among Democrats but not for individuals of other political orientations. An exception to this finding occurs with school shootings, which mobilize broad support for firearm legislation among both Democrats and Republicans
From inclusion to epistemic belonging in international environmental expertise: learning from the institutionalisation of scenarios and models in IPBES
No full textThe inclusion of diverse perspectives from different disciplines, genders and locations has become a foreground concern in environmental expertise. While inclusion is increasingly accounted for in the design and evaluation of expert organisations, questions remain about the extent to which the pursuit of inclusion equates to effective participation. Building on recent scholarship on expertise in environmental sociology and public participation in environmental governance, this paper puts forward the argument that enabling inclusion in international expert organisations can be supported by facilitating epistemic belonging – a state achieved not only through mutual recognition of skilful practice amongst their expert communities (i.e. group belonging) but also the mobilisation of material resources within and beyond these organisations that enable participating experts to assert their importance, define their specialist skills and to effectively enact their epistemic practices. In this account, I trace the institutionalization of biodiversity scenarios and models in the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) to show how achieving epistemic belonging requires expert communities to actively reshape the resource environments in which they operate. This account extends current sociological perspectives on environmental expertise and offers insights for environmental expert organisations seeking to broaden their inclusion practices
Study protocol: The OxWell annual school survey investigating social, emotional and behavioural factors associated with mental health and wellbeing
No full textIntroduction Improving our understanding of the broad range of social, emotional and behavioural factors that contribute to mental health outcomes in adolescents will be greatly enhanced with diverse, representative population samples. We present a protocol for a repeated self-report survey assessing risk and protective factors for mental health and well-being in school pupils aged 8–18 years with different socioeconomic backgrounds in England. The survey will provide a comprehensive picture of mental health and associated risks at the community level to inform the development of primary and secondary prevention and treatment strategies in schools.
Methods and analysis This protocol is for a large-scale online repeated self-report survey, representative of children and adolescents aged 8–18 years attending schools or further education colleges in participating counties in England. The survey consists of around 300 questions, including validated measures of mental health and well-being, risk and protective factors, and care-seeking behaviour and preferences. Additional questions each year vary to address current events and novel hypotheses, developed by the research team, collaborators and stakeholders. Primary analyses will investigate current and changing risk and protective factors, care-seeking behaviour and attitudes to allowing linkage of their sensitive data to other databases for research, and will compare measures of mental health to measures of well-being.
Ethics and dissemination The study was approved by the University of Oxford Research Ethics Committee (Reference: R62366). Tailored data summaries will be provided to participating schools and stakeholders within 3 months of data collection. The main findings will be presented at scientific meetings, published in peer-reviewed journals and shared via digital and social media channels. At the end of the study, other researchers will be able to apply for access to anonymous data extracts
Effect of vitamin D supplementation on aromatase inhibitor-related musculoskeletal side effects for breast cancer: B-ABLE cohort
No full textObjective: To assess the effect of vitamin D supplementation on musculoskeletal complications related to aromatase inhibitor (AI) treatment in patients with breast cancer.
Material and methods: Prospective observational study of women undergoing AI treatment, recruited in the B‐ABLE cohort. Patients with baseline serum 25 (OH) D (25‐hydroxyvitamin D) levels 0 at 3 months, was evaluated using logistic regression.
Results: Vitamin D supplementation at the start of AI treatment decreased the risk of both incident arthralgia and its worsening. The effective threshold of 25 (OH) D in serum to reduce joint pain was established at 40 ng/ml. However, this threshold was not significantly related to bone changes at one year of follow‐up. However, vitamin D levels were in‐ versely correlated with lumbar spine bone loss (LS) (β=0.177% [95% CI: 0.014 to 0.340]).
Conclusions: Vitamin D supplementation aimed at achieving serum 25(OH)D levels of at least 40 ng/ml is protective for arthralgia. Vitamin D levels at three months could predict the risk of bone loss in LS at one year of AI treatment. The‐ refore, high doses of vitamin D are recommended in these patients, who are more prone to musculoskeletal conditions
Adapting non-invasive human recordings along multiple task-axes shows unfolding of spontaneous and over-trained choice
No full textChoices rely on a transformation of sensory inputs into motor responses. Using invasive single neuron recordings, the evolution of a choice process has been tracked by projecting population neural responses into state spaces. Here, we develop an approach that allows us to recover similar trajectories on a millisecond timescale in non-invasive human recordings. We selectively suppress activity related to three task-axes, relevant and irrelevant sensory inputs and response direction, in magnetoencephalography data acquired during context-dependent choices. Recordings from premotor cortex show a progression from processing sensory input to processing the response. In contrast to previous macaque recordings, information related to choice-irrelevant features is represented more weakly than choice-relevant sensory information. To test whether this mechanistic difference between species is caused by extensive over-training common in non-human primate studies, we trained humans on >20,000 trials of the task. Choice-irrelevant features were still weaker than relevant features in premotor cortex after over-training