High Sensitivity DNA Detection Using Gold Nanoparticle Functionalised Polyaniline Nanofibres

Polyaniline (PANI) nanofibres (PANI-NF) have been modified with chemically grown gold nanoparticles to give a nanocomposite material (PANI-NF–AuNP) and deposited on gold electrodes. Single stranded capture DNA was then bound to the gold nanoparticles and the underlying gold electrode and allowed to hybridise with a complementary target strand that is uniquely associated with the pathogen, Staphylococcus aureus (S. aureus), that causes mastitis. Significantly, cyclic voltammetry demonstrates that deposition of the gold nanoparticles increases the area available for DNA immobilisation by a factor of approximately 4. EPR reveals that the addition of the Au nanoparticles efficiently decreases the interactions between adjacent PANI chains and/or motional broadening. Finally, a second horseradish peroxidase (HRP) labelled DNA strand hybridises with the target allowing the concentration of the target DNA to be detected by monitoring the reduction of a hydroquinone mediator in solution. The sensors have a wide dynamic range, excellent ability to discriminate DNA mismatches and a high sensitivity. Semi-log plots of the pathogen DNA concentration vs. faradaic current were linear from 150 × 10−12 to 1 × 10−6 mol L−1 and pM concentrations could be detected without the need for molecular, e.g., PCR or NASBA, amplification

Processable aqueous dispersions of graphene nanosheets

Graphene sheets offer extraordinary electronic, thermal and mechanical properties and are expected to find a variety of applications. A prerequisite for exploiting most proposed applications for graphene is the availability of processable graphene sheets in large quantities. The direct dispersion of hydrophobic graphite or graphene sheets in water without the assistance of dispersing agents has generally been considered to be an insurmountable challenge. Here we report that chemically converted graphene sheets obtained from graphite can readily form stable aqueous colloids through electrostatic stabilization. This discovery has enabled us to develop a facile approach to large-scale production of aqueous graphene dispersions without the need for polymeric or surfactant stabilizers. Our findings make it possible to process graphene materials using low-cost solution processing techniques, opening up enormous opportunities to use this unique carbon nanostructure for many technological applications

Functional methods in the theory of magnetoimpurity states of electrons in quantum wires

Functional methods are used to study magnetoimpurity states of electrons in nanostructures. The Keldysh formalism is applied to these states. The theory is illustrated using a quantum wire sample with impurity atoms capable of localizing electrons in a magnetic field. The characteristics of magnetoimpurity states of electrons in the wire are calculated using the model of a Gaussian separable potential.Comment: 15 pages, 1 figur

Acoustic Cyclotron Resonance and Giant High Frequency Magnetoacoustic Oscillations in Metals with Locally Flattened Fermi Surface

We consider the effect of local flattening on the Fermi surface (FS) of a metal upon geometric oscillations of the velocity and attenuation of ultrasonic waves in the neighborhood of the acoustic cyclotron resonance. It is shown that such peculiarities of the local geometry of the FS can lead to a significant enhancement of both cyclotron resonance and geometric oscillations. Characteristic features of the coupling of ultrasound to shortwave cyclotron waves arising due to the local flattening of the FS are analyzed. PACS numbers 71.18.+y; 72.15.Gd; 72.15.-vComment: 8 pages, 3 figures, text revise

Qualitative Evaluation of Web-Based Digital Intervention to Prevent and Reduce Excessive Alcohol Use and Harm Among Young People Aged 14-15 Years: A "Think-Aloud" Study

BACKGROUND: In the United Kingdom, despite some downward trends in alcohol use among young people, over one-fifth of young people reported excessive alcohol use in the past month, which is associated with short- and long-term harm to health. Digital interventions to reduce alcohol use, such as websites, among young people present an appealing and cost-effective mode of intervention that can be integrated into the education system. However, relatively few school-based digital alcohol-focused interventions have been developed and evaluated for young people in the United Kingdom. OBJECTIVE: This study aims to develop a novel web-based intervention, Rethink Alcohol, to prevent and reduce excessive alcohol use and related harm among young people aged between 14 and 15 years, and explore the views of young people, teachers, and youth workers in relation to the content, design, and usability of the intervention. METHODS: Intervention development followed the person-based approach, using theories of social norms and social influence. Qualitative "Think-Aloud" interviews, either one-to-one or paired, were conducted while participants perused and worked through the web-based intervention, talking aloud. Participants included 20 young people (12 female, 8 male), 5 youth workers (4 female, 1 male), 3 teachers (2 male, 1 female), and 1 (male) clinical professional, recruited via youth groups and professional networks. Interviews were audio recorded, transcribed verbatim, and analyzed thematically. RESULTS: The prototype web-based intervention included normative feedback, information, a quiz, interactive activities, and scenarios. On a rating scale of impressions from poor (1) to excellent (5), participants gave an average score of 3.6/5. A total of 5 themes were identified: content, credibility of the website, making the website easy to understand, design and navigation, and suitability for the audience. These themes reflected views that the content was interesting, credible, informative, and embodied a neutral and nonjudgmental tone, but stronger messaging was needed regarding social pressures and short-term risks regarding safety and risk behavior alongside clarity around pathways of risk; credibility and trustworthiness of information were critical features, determined in part, by the professionalism of design and referencing of sources of information provided; and messages should be succinct and come to life through design and interactive features. CONCLUSIONS: Together, the data illustrated the importance and challenge of communicating nuanced alcohol-focused public health messages to young people in concise, clear, nonjudgmental, and appealing ways. Young people report interest in clear, credible, neutral, and interactive messages regarding social pressures and short-term risks of alcohol use via a web-based intervention. There is scope for optimization and feasibility testing of the Rethink Alcohol intervention

The Effectiveness of Alcohol Screening and Brief Intervention in Emergency Departments: A Multicentre Pragmatic Cluster Randomized Controlled Trial

BACKGROUND: Alcohol misuse is common in people attending emergency departments (EDs) and there is some evidence of efficacy of alcohol screening and brief interventions (SBI). This study investigated the effectiveness of SBI approaches of different intensities delivered by ED staff in nine typical EDs in England: the SIPS ED trial. METHODS AND FINDINGS: Pragmatic multicentre cluster randomized controlled trial of SBI for hazardous and harmful drinkers presenting to ED. Nine EDs were randomized to three conditions: a patient information leaflet (PIL), 5 minutes of brief advice (BA), and referral to an alcohol health worker who provided 20 minutes of brief lifestyle counseling (BLC). The primary outcome measure was the Alcohol Use Disorders Identification Test (AUDIT) status at 6 months. Of 5899 patients aged 18 or more presenting to EDs, 3737 (63·3%) were eligible to participate and 1497 (40·1%) screened positive for hazardous or harmful drinking, of whom 1204 (80·4%) gave consent to participate in the trial. Follow up rates were 72% (n?=?863) at six, and 67% (n?=?810) at 12 months. There was no evidence of any differences between intervention conditions for AUDIT status or any other outcome measures at months 6 or 12 in an intention to treat analysis. At month 6, compared to the PIL group, the odds ratio of being AUDIT negative for brief advice was 1·103 (95% CI 0·328 to 3·715). The odds ratio comparing BLC to PIL was 1·247 (95% CI 0·315 to 4·939). A per protocol analysis confirmed these findings. CONCLUSIONS: SBI is difficult to implement in typical EDs. The results do not support widespread implementation of alcohol SBI in ED beyond screening followed by simple clinical feedback and alcohol information, which is likely to be easier and less expensive to implement than more complex interventions

Impact of practice, provider and patient characteristics on delivering screening and brief advice for heavy drinking in primary health care secondary analyses of data from the ODHIN five country cluster randomized factorial trial

BACKGROUND: The implementation of primary healthcare-based screening and advice that is effective in reducing heavy drinking can be enhanced with training. OBJECTIVES: Undertaking secondary analysis of the five-country ODHIN study, we test: the extent to which practice, provider and patient characteristics affect the likelihood of patients being screened and advised; the extent to which such characteristics moderate the impact of training in increasing screening and advice; and the extent to which training mitigates any differences due to such characteristics found at baseline. METHODS: A cluster randomized factorial trial involving 120 practices, 746 providers and 46 546 screened patients from Catalonia, England, the Netherlands, Poland, and Sweden. Practices were randomized to receive training or not to receive training. The primary outcome measures were the proportion of adult patients screened, and the proportion of screen-positive patients advised. RESULTS: Nurses tended to screen more patients than doctors (OR = 3.1; 95%CI: 1.9, 4.9). Screen-positive patients were more likely to be advised by doctors than by nurses (OR = 2.3; 95%CI: 1.4, 4.1), and more liable to be advised the higher their risk status (OR = 1.9; 95%CI: 1.3, 2.7). Training increased screening and advice giving, with its impact largely unrelated to practice, provider or patient characteristics. Training diminished the differences between doctors and nurses and between patients with low or high-risk status. CONCLUSIONS: Training primary healthcare providers diminishes the negative impacts that some practice, provider and patient characteristics have on the likelihood of patients being screened and advised. Trial registration ClinicalTrials.gov. Trial identifier: NCT01501552

How effective are brief interventions in reducing alcohol consumption::do the setting, practitioner group and content matter? Findings from a systematic review and metaregression analysis

Background: While the efficacy and effectiveness of brief interventions for alcohol (ABI) have been demonstrated in primary care, there is weaker evidence in other settings and reviews do not consider differences in content. We conducted a systematic review to measure the effect of ABIs on alcohol consumption and how it differs by the setting, practitioner group and content of intervention. Methods: We searched MEDLINE, EMBASE, PsycINFO; CINAHL, Social Science Citation Index, Cochrane Library and Global Health up to January 2015 for randomised controlled trials that measured effectiveness of ABIs on alcohol consumption. We grouped outcomes into measures of quantity and frequency indices. We used multilevel meta-analysis to estimate pooled effect sizes and tested for the effect of moderators through a multiparameter Wald test. Stratified analysis of a subset of quantity and frequency outcomes was conducted as a sensitivity check. Results: 52 trials were included contributing data on 29 891 individuals. ABIs reduced the quantity of alcohol consumed by 0.15 SDs. While neither the setting nor content appeared to significantly moderate intervention effectiveness, the provider did in some analyses. Interventions delivered by nurses had the most effect in reducing quantity (d=−0.23, 95% CI (−0.33 to −0.13)) but not frequency of alcohol consumption. All content groups had statistically significant mean effects, brief advice was the most effective in reducing quantity consumed (d=−0.20, 95% CI (−0.30 to −0.09)). Effects were maintained in the stratified sensitivity analysis at the first and last assessment time. Conclusions: ABIs play a small but significant role in reducing alcohol consumption. Findings show the positive role of nurses in delivering interventions. The lack of evidence on the impact of content of intervention r

Radiation of Neutron Stars Produced by Superfluid Core

We find that neutron star interior is transparent for collisionless electron sound, the same way as it is transparent for neutrinos. In the presence of magnetic field the electron sound is coupled with electromagnetic radiation and form the fast magnetosonic wave. We find that electron sound is generated by superfluid vortices in the stellar core. Thermally excited helical vortex waves produce fast magnetosonic waves in the stellar crust which propagate toward the surface and transform into outgoing electromagnetic radiation. The vortex radiation has the spectral index -0.45 and can explain nonthermal radiation of middle-aged pulsars observed in the infrared, optical and hard X-ray bands. The radiation is produced in the stellar interior which allows direct determination of the core temperature. Comparing the theory with available spectra observations we find that the core temperature of the Vela pulsar is T=8*10^8K, while the core temperature of PSR B0656+14 and Geminga exceeds 2*10^8K. This is the first measurement of the temperature of a neutron star core. The temperature estimate rules out equation of states incorporating Bose condensations of pions or kaons and quark matter in these objects. Based on the temperature estimate and cooling models we determine the critical temperature of triplet neutron superfluidity in the Vela core Tc=(7.5\pm 1.5)*10^9K which agrees well with recent data on behavior of nucleon interactions at high energies. Another finding is that in the middle aged neutron stars the vortex radiation, rather then thermal conductivity, is the main mechanism of heat transfer from the stellar core to the surface. Electron sound opens a perspective of direct spectroscopic study of superdense matter in the neutron star interiors.Comment: 43 pages, 7 figures, to appear in Astrophysical Journa

Factors associated with alcohol reduction in harmful and hazardous drinkers following alcohol brief intervention in Scotland: a qualitative enquiry

Background: Alcohol Brief Intervention (ABI) uses a motivational counselling approach to support individuals to reduce excessive alcohol consumption. There is growing evidence on ABI’s use within various health care settings, although how they work and which components enhance success is largely unknown. This paper reports on the qualitative part of a mixed methods study. It explores enablers and barriers associated with alcohol reduction following an ABI. It focuses on alcohol’s place within participants’ lives and their personal perspectives on reducing consumption. There are a number of randomised controlled trials in this field though few ABI studies have addressed the experiences of hazardous/harmful drinkers. This study examines factors associated with alcohol reduction in harmful/hazardous drinkers following ABI. Methods: This qualitative study was underpinned by a realist evaluation approach and involved semistructured interviews with ten harmful or hazardous alcohol drinkers. Participants (n = 10) were from the intervention arm of a randomised controlled trial (n = 124). All had received ABI, a 20 min motivational counselling interview, six months previously, and had reduced their alcohol consumption. Interviews were recorded, transcribed verbatim and thematically analysed. Results: Participants described their views on alcohol, its’ place in their lives, their personal perspectives on reducing their consumption and future aspirations. Conclusions: The findings provide an insight into participants’ views on alcohol, ABI, and the barriers and enablers to change. Participants described a cost benefit analysis, with some conscious consideration of the advantages and disadvantages of reducing intake or abstaining from alcohol. Findings suggest that, whilst hospital admission can act as a catalyst, encouraging individuals to reflect on their alcohol consumption through ABI may consolidate this, turning this reflective moment into action. Sustainability may be enhanced by the presence of a ‘significant other’ who encourages and experiences benefit. In addition having a purpose or structure with activities linked to employment and/or social and leisure pursuits offers the potential to enhance and sustain reduced alcohol consumption. Trial registration: Trial registration number TRN NCT00982306 September 22nd 200