3,513 research outputs found
Swimming using surface acoustic waves
Microactuation of free standing objects in fluids is currently dominated by the rotary propeller, giving rise to a range of potential applications in the military, aeronautic and biomedical fields. Previously, surface acoustic waves (SAWs) have been shown to be of increasing interest in the field of microfluidics, where the refraction of a SAW into a drop of fluid creates a convective flow, a phenomenon generally known as SAW streaming. We now show how SAWs, generated at microelectronic devices, can be used as an efficient method of propulsion actuated by localised fluid streaming. The direction of the force arising from such streaming is optimal when the devices are maintained at the Rayleigh angle. The technique provides propulsion without any moving parts, and, due to the inherent design of the SAW transducer, enables simple control of the direction of travel
Patterns of analgesic use, pain and self-efficacy: a cross-sectional study of patients attending a hospital rheumatology clinic
Background: Many people attending rheumatology clinics use analgesics and non-steroidal anti-inflammatories for persistent musculoskeletal pain. Guidelines for pain management recommend regular and pre-emptive use of analgesics to reduce the impact of pain. Clinical experience indicates that analgesics are often not used in this way. Studies exploring use of analgesics in arthritis have historically measured adherence to such medication. Here we examine patterns of analgesic use and their relationships to pain, self-efficacy and demographic factors.
Methods: Consecutive patients were approached in a hospital rheumatology out-patient clinic. Pattern of analgesic use was assessed by response to statements such as 'I always take my tablets every day.' Pain and self-efficacy (SE) were measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Arthritis Self-Efficacy Scale (ASES). Influence of factors on pain level and regularity of analgesic use were investigated using linear regression. Differences in pain between those agreeing and disagreeing with statements regarding analgesic use were assessed using t-tests.
Results: 218 patients (85% of attendees) completed the study. Six (2.8%) patients reported no current pain, 26 (12.3%) slight, 100 (47.4%) moderate, 62 (29.4%) severe and 17 (8.1%) extreme pain. In multiple linear regression self efficacy and regularity of analgesic use were significant (p < 0.01) with lower self efficacy and more regular use of analgesics associated with more pain.
Low SE was associated with greater pain: 40 (41.7%) people with low SE reported severe pain versus 22 (18.3%) people with high SE, p < 0.001. Patients in greater pain were significantly more likely to take analgesics regularly; 13 (77%) of those in extreme pain reported always taking their analgesics every day, versus 9 (35%) in slight pain. Many patients, including 46% of those in severe pain, adjusted analgesic use to current pain level. In simple linear regression, pain was the only variable significantly associated with regularity of analgesic use: higher levels of pain corresponded to more regular analgesic use (p = 0.003).
Conclusion: Our study confirms that there is a strong inverse relationship between self-efficacy and pain severity. Analgesics are often used irregularly by people with arthritis, including some reporting severe pain
BNCI systems as a potential assistive technology: ethical issues and participatory research in the BrainAble project
This paper highlights aspects related to current research and thinking about ethical issues in relation to Brain Computer Interface (BCI) and Brain-Neuronal Computer Interfaces (BNCI) research through the experience of one particular project, BrainAble, which is exploring and developing the potential of these technologies to enable people with complex disabilities to control computers. It describes how ethical practice has been developed both within the multidisciplinary research team and with participants. Results: The paper presents findings in which participants shared their views of the project prototypes, of the potential of BCI/BNCI systems as an assistive technology, and of their other possible applications. This draws attention to the importance of ethical practice in projects where high expectations of technologies, and representations of “ideal types” of disabled users may reinforce stereotypes or drown out participant “voices”. Conclusions: Ethical frameworks for research and development in emergent areas such as BCI/BNCI systems should be based on broad notions of a “duty of care” while being sufficiently flexible that researchers can adapt project procedures according to participant needs. They need to be frequently revisited, not only in the light of experience, but also to ensure they reflect new research findings and ever more complex and powerful technologies
The detection of the imprint of filaments on cosmic microwave background lensing
Galaxy redshift surveys, such as 2dF, SDSS, 6df, GAMA and VIPERS, have shown
that the spatial distribution of matter forms a rich web, known as the cosmic
web. The majority of galaxy survey analyses measure the amplitude of galaxy
clustering as a function of scale, ignoring information beyond a small number
of summary statistics. Since the matter density field becomes highly
non-Gaussian as structure evolves under gravity, we expect other statistical
descriptions of the field to provide us with additional information. One way to
study the non-Gaussianity is to study filaments, which evolve non-linearly from
the initial density fluctuations produced in the primordial Universe. In our
study, we report the first detection of CMB (Cosmic Microwave Background)
lensing by filaments and we apply a null test to confirm our detection.
Furthermore, we propose a phenomenological model to interpret the detected
signal and we measure how filaments trace the matter distribution on large
scales through filament bias, which we measure to be around 1.5. Our study
provides a new scope to understand the environmental dependence of galaxy
formation. In the future, the joint analysis of lensing and Sunyaev-Zel'dovich
observations might reveal the properties of `missing baryons', the vast
majority of the gas which resides in the intergalactic medium and has so far
evaded most observations
Functional diversity of marine ecosystems after the Late Permian mass extinction event
Article can be accessed from http://www.nature.com/ngeo/journal/v7/n3/full/ngeo2079.htmlThe Late Permian mass extinction event was the most severe such crisis of the past 500 million years and occurred during an episode of global warming. It is assumed to have had significant ecological impact, but its effects on marine ecosystem functioning are unknown and the patterns of marine recovery are debated. We analysed the fossil occurrences of all known Permian-Triassic benthic marine genera and assigned each to a functional group based on their inferred life habit. We show that despite the selective extinction of 62-74% of marine genera there was no significant loss of functional diversity at the global scale, and only one novel mode of life originated in the extinction aftermath. Early Triassic marine ecosystems were not as ecologically depauperate as widely assumed, which explains the absence of a Cambrian-style Triassic radiation in higher taxa. Functional diversity was, however, significantly reduced in particular regions and habitats, such as tropical reefs, and at these scales recovery varied spatially and temporally, probably driven by migration of surviving groups. Marine ecosystems did not return to their pre-extinction state, however, and radiation of previously subordinate groups such as motile, epifaunal grazers led to greater functional evenness by the Middle Triassic
Adolescents’ responses to the promotion and flavouring of e-cigarettes
Objectives
The purpose of the study is to examine adolescents’ awareness of e-cigarette marketing and investigate the impact of e-cigarette flavour descriptors on perceptions of product harm and user image.
Methods
Data come from the 2014 Youth Tobacco Policy Survey, a cross-sectional in-home survey conducted with 11–16 year olds across the UK (n = 1205). Adolescents’ awareness of e-cigarette promotion, brands, and flavours was assessed. Perceptions of product harm, and likely user of four examples of e-cigarette flavours was also examined.
Results
Some participants had tried e-cigarettes (12 %) but regular use was low (2 %) and confined to adolescents who had also smoked tobacco. Most were aware of at least one promotional channel (82 %) and that e-cigarettes came in different flavours (69 %). Brand awareness was low. E-cigarettes were perceived as harmful (M = 3.54, SD = 1.19) but this was moderated by product flavours. Fruit and sweet flavours were perceived as more likely to be tried by young never smokers than adult smokers trying to quit (p < 0.001).
Conclusions
There is a need to monitor the impact of future market and regulatory change on youth uptake and perceptions of e-cigarettes
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International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci.
The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5-20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson's disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations
Ganho de peso, dislipidemia e parâmetros alterados para síndrome metabólica em pacientes de primeiro episódio psicótico após seguimento de seis meses
OBJECTIVES: Obesity and metabolic abnormalities are frequent in psychotic patients, including first-episode psychosis. We evaluated weight and metabolic parameters in first-episode psychotic outpatients from the First Episode Psychosis Program, Universidade Federal de São Paulo (UNIFESP). METHOD: Weight, height, waist and hip circumferences, glucose and lipid levels were measured at baseline and after a six-month period. RESULTS: Fifty-seven patients were included and 44 (77.2%) of them finished the study. Patients had a median age of 26.3 years, 60% were men and 43% had a diagnosis of schizophrenia at the endpoint. Weight and BMI values increased significantly during the follow-up (p < 0.01). The average weight gain at the follow-up was 10.1% of the baseline weight (SD = 11.9). Only women presented significant waist abnormalities: at the first assessment the waist mean was 79.12 cm (SD = 10.68) and 6 months later it had increased to 89.65 cm (SD = 11.19, z = -3.182, p = 0.001). After 6 months, the total cholesterol (p = 0.004), and triglyceride levels (p = 0.016) increased, while HDL-cholesterol levels decreased (p = 0.025). During the follow-up period one patient (2.3%) developed diabetes mellitus, one (2.3%) presented altered fasting glucose, 12 (27.2%) patients developed at least two altered parameters for metabolic syndrome and 3 (6.8%) patients developed metabolic syndrome (p = 0.001). DISCUSSION: The results of this study showed that in a short period of time individuals under antipsychotic treatment had their weight increased significantly and developed important metabolic abnormalities. CONCLUSIONS: Clinicians should be aware of these risks, choose an antipsychotic that causes less weight gain and should monitor these patients carefully, and recommend prophylactic measures as diet restriction and physical activities.OBJETIVOS: Obesidade e alterações metabólicas são freqüentes em pacientes psicóticos, inclusive no primeiro episódio psicótico. Foram avaliados peso e parâmetros metabólicos em pacientes em tratamento no Programa de Episódio Psicótico da Universidade Federal de São Paulo (UNIFESP). MÉTODO: Peso, altura, medida de cintura e quadril, glicemia e perfil lipídico foram avaliados no início do tratamento e após seis meses. RESULTADOS: Cinqüenta e sete pacientes foram incluídos no estudo e 44 (72%) concluíram o estudo. Os pacientes apresentavam em média 26,3 anos, 60% eram do sexo masculino e, ao final do estudo, 43% apresentavam diagnóstico de esquizofrenia. Houve aumento significativo do peso e índice de massa corporal durante o estudo (p < 0,01). Em média, o peso aumentou 10,1% do peso inicial (SD = 11,9). Apenas mulheres apresentaram alterações na medida da cintura: no início, a média da cintura era de 79,12 cm (SD = 10,68) e, após seis meses, houve um aumento para 89,65 cm (SD = 11,19, z = -3,182, p = 0,001). Após seis meses, houve aumento do colesterol total (p = 0,004) e triglicérides (p = 0,016), e diminuição dos níveis de colesterol HDL (p = 0,025). No período, um paciente (2,3%) desenvolveu diabetes mellitus, um paciente (2,3%) apresentou glicemia de jejum alterada, 12 (27,2%) desenvolveram pelo menos dois parâmetros alterados para síndrome metabólica, e 3 (6,8%) apresentaram síndrome metabólica (p = 0,001). DISCUSSÃO: Os resultados deste estudo mostram que em um curto período de tempo pacientes em tratamento com antipsicóticos aumentaram substancialmente o peso e desenvolveram importantes alterações metabólicas. CONCLUSÃO: Os clínicos devem estar atentos a esses riscos, escolher medicações que causem menor ganho de peso, devendo monitorar esses pacientes cuidadosamente e recomendar medidas profiláticas como restrição dietética e atividade física.Universidade Federal de São Paulo (UNIFESP) Department of Psychiatry First-episode Psychosis ProgramUNIFESP, Department of Psychiatry First-episode Psychosis ProgramSciEL
Genome sequence of an Australian kangaroo, Macropus eugenii, provides insight into the evolution of mammalian reproduction and development.
BACKGROUND: We present the genome sequence of the tammar wallaby, Macropus eugenii, which is a member of the kangaroo family and the first representative of the iconic hopping mammals that symbolize Australia to be sequenced. The tammar has many unusual biological characteristics, including the longest period of embryonic diapause of any mammal, extremely synchronized seasonal breeding and prolonged and sophisticated lactation within a well-defined pouch. Like other marsupials, it gives birth to highly altricial young, and has a small number of very large chromosomes, making it a valuable model for genomics, reproduction and development. RESULTS: The genome has been sequenced to 2 × coverage using Sanger sequencing, enhanced with additional next generation sequencing and the integration of extensive physical and linkage maps to build the genome assembly. We also sequenced the tammar transcriptome across many tissues and developmental time points. Our analyses of these data shed light on mammalian reproduction, development and genome evolution: there is innovation in reproductive and lactational genes, rapid evolution of germ cell genes, and incomplete, locus-specific X inactivation. We also observe novel retrotransposons and a highly rearranged major histocompatibility complex, with many class I genes located outside the complex. Novel microRNAs in the tammar HOX clusters uncover new potential mammalian HOX regulatory elements. CONCLUSIONS: Analyses of these resources enhance our understanding of marsupial gene evolution, identify marsupial-specific conserved non-coding elements and critical genes across a range of biological systems, including reproduction, development and immunity, and provide new insight into marsupial and mammalian biology and genome evolution
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