No abstract

Understanding magnetic-field generation and amplification in turbulent plasma is essential to account for observations of magnetic fields in the universe. A theoretical framework attributing the origin and sustainment of these fields to the so-called fluctuation dynamo was recently validated by experiments on laser facilities in low-magnetic-Prandtl-number plasmas (Pm<1). However, the same framework proposes that the fluctuation dynamo should operate differently when Pm≳1, the regime relevant to many astrophysical environments such as the intracluster medium of galaxy clusters. This paper reports an experiment that creates a laboratory Pm≳1 plasma dynamo. We provide a time-resolved characterization of the plasma’s evolution, measuring temperatures, densities, flow velocities, and magnetic fields, which allows us to explore various stages of the fluctuation dynamo’s operation on seed magnetic fields generated by the action of the Biermann-battery mechanism during the initial drive-laser target interaction. The magnetic energy in structures with characteristic scales close to the driving scale of the stochastic motions is found to increase by almost three orders of magnitude and saturate dynamically. It is shown that the initial growth of these fields occurs at a much greater rate than the turnover rate of the driving-scale stochastic motions. Our results point to the possibility that plasma turbulence produced by strong shear can generate fields more efficiently at the driving scale than anticipated by idealized magnetohydrodynamics (MHD) simulations of the nonhelical fluctuation dynamo; this finding could help explain the large-scale fields inferred from observations of astrophysical systems.

Background. There is a widely held expectation that GPs will routinely use opportunities to provide opportunistic screening and brief intervention for alcohol and other drug (AOD) abuse, a major cause of preventable death and morbidity.Aim. To explore how opportunities arise for AOD discussion in GP consultations and how that advice is delivered.Design. Analysis of video-recorded primary care consultationsSetting. New Zealand General Practice.Methods. Interactional content analysis of AOD consultations between 15 GP’s and 56 patients identified by keyword search from a bank of digital video consultation recordings.Results. AOD-related words were found in almost one-third (56/171) of the GP consultation transcripts (22 female and 34 male patients). The AOD dialogue varied from brief mention to pertinent advice. Tobacco and alcohol discussion featured more often than misuse of anxiolytics, night sedation, analgesics and caffeine, with only one direct enquiry about other (unspecified) recreational drug use. Discussion was associated with interactional delicacy on the part of both doctor and patient, manifested by verbal and non-verbal discomfort, use of closed statements, understatement, wry humour and sudden topic change.Conclusions. Mindful prioritization of competing demands, time pressures, topic delicacy and the acuteness of the presenting complaint can impede use of AOD discussion opportunities. Guidelines and tools for routine screening and brief intervention in primary care do not accommodate this reality. Possible responses to enhance AOD conversations within general practice settings are discussed.

Objetivos: avaliar os cuidados de enfermagem relacionados ao cateter venoso central (CVC) em uma unidade de Terapia Intensiva adulto e pediátrica, comparar a conduta ao protocolo padronizado na instituição e analisar os resultados baseando-se no manual da Agência Nacional de Vigilância de 2017. Metodologia: trata-se de uma auditoria clínica realizada em um hospital público de Minas Gerais. Foram selecionados os pacientes portadores de CVC, internados em leito par no período de junho e julho de 2017 no setor. Os dados foram coletados através do preenchimento de instrumento elaborado pela autora para a auditoria, através de observação direta da troca de curativo do CVC. Resultados: foram avaliadas 15 trocas de curativo, realizadas por 6 enfermeiros. As principais informações extraídas do estudo foram sistematizadas em quatro tópicos: dados relacionados ao paciente, ao cateter venoso central, aos materiais utilizados na realização do curativo e aos cuidados de enfermagem. Conclusão: a auditoria no cuidado de enfermagem na troca de curativo de CVC favoreceu um processo educativo entre os enfermeiros, contribuiu para identificar estratégias para melhorar a assistência e propôs uma atualização do protocolo da instituição.

Rapamycin is known to extend lifespan. We conducted a randomized placebo-controlled study of enteric rapamycin-treatment to evaluate its effect on physical function in old low capacity runner (LCR) rats, a rat model selected from diverse genetic background for low intrinsic aerobic exercise capacity without genomic manipulation and characterized by increased complex disease risks and aging phenotypes. The study was performed in 12 male and 16 female LCR rats aged 16-22 months at baseline. The treatment group was fed with rapamycin-containing diet pellets at approximately 2.24mg/kg body weight per day and the placebo group with the same diet without rapamycin for six months. Observation was extended for additional 2 months. Physical function measurements include grip strength measured as maximum tensile force using a rat grip strength meter and maximum running distance (MRD) using rat physical treadmill test. The results showed that rapamycin improved grip strength by 13% (p=.036) and 60% (p<.001) from its baseline in female and male rats, respectively. Rapamycin attenuated MRD decline by 66% (p<.001) and 46% (p=.319) in females and males, respectively. These findings provide initial evidence for beneficial effect of rapamycin on physical functioning in an aging rat model of high disease risks with significant implication in humans.