BiSON pockels-cell list

The Birmingham Solar-Oscillations Network Group has owned, and destroyed, many Pockels cells over the years

The Ages of the Thin Disk, Thick Disk, and the Halo from Nearby White Dwarfs

We present a detailed analysis of the white dwarf luminosity functions derived from the local 40 pc sample and the deep proper motion catalog of Munn et al (2014, 2017). Many of the previous studies ignored the contribution of thick disk white dwarfs to the Galactic disk luminosity function, which results in an erronous age measurement. We demonstrate that the ratio of thick/thin disk white dwarfs is roughly 20\% in the local sample. Simultaneously fitting for both disk components, we derive ages of 6.8-7.0 Gyr for the thin disk and 8.7 $\pm$ 0.1 Gyr for the thick disk from the local 40 pc sample. Similarly, we derive ages of 7.4-8.2 Gyr for the thin disk and 9.5-9.9 Gyr for the thick disk from the deep proper motion catalog, which shows no evidence of a deviation from a constant star formation rate in the past 2.5 Gyr. We constrain the time difference between the onset of star formation in the thin disk and the thick disk to be $1.6^{+0.3}_{-0.4}$ Gyr. The faint end of the luminosity function for the halo white dwarfs is less constrained, resulting in an age estimate of $12.5^{+1.4}_{-3.4}$ Gyr for the Galactic inner halo. This is the first time ages for all three major components of the Galaxy are obtained from a sample of field white dwarfs that is large enough to contain significant numbers of disk and halo objects. The resultant ages agree reasonably well with the age estimates for the oldest open and globular clusters.Comment: ApJ, in pres

Developing a community HCV service: project ITTREAT (Integrated Community based Test - stage - TREAT) service for people who inject drugs

Liver disease is now the third most common cause of premature death in the UK, with chronic viral hepatitis being an important contributory factor. Often the diagnosis of chronic liver disease is only made when patients present late in the disease trajectory. This underscores the importance of near patient testing and linkage into care. The need for community based models for liver disease is in line with the recently commissioned National Liver report, which calls for assessment and treatment of high-risk individuals in the community. In this manuscript our objectives are to discuss the need for community services for individuals with hepatitis C virus (HCV) infection and give an overview of the different community models for HCV. Finally we describe our experiences in setting up a successful nurse led service for screening, stratification and treatment of HCV related liver disease at a substance misuse service. We highlight the important stages of this process including engaging with stakeholders, obtaining funding and service set up. We also explore the obstacles and challenges faced and summarise our key recommendations. A brief summary of interim clinical outcomes is also presented

Characterising the Analgesic Effect of Different Targets for Deep Brain Stimulation in Trigeminal Anaesthesia Dolorosa

BACKGROUND: Several deep brain stimulation (DBS) targets have been explored for the alleviation of trigeminal anaesthesia dolorosa. We aimed to characterise the analgesia produced from the periaqueductal grey (PAG) and centromedian-parafascicular (CmPf) nucleus using a within-subject design. METHOD: We report a case series of 3 subjects implanted with PAG and CmPf DBS systems for the treatment of anaesthesia dolorosa. At follow-up, testing of onset and offset times, magnitude, and thermal and mechanical sensitivity was performed. RESULTS: The mean pain score of the cohort was acutely reduced by 56% (p < 0.05) with PAG and 67% (p < 0.01) with CmPf stimulation at mean time intervals of 38 and 16 min, respectively. The onset time was 12.5 min (p < 0.05) for PAG stimulation and 2.5 min (p < 0.01) for CmPf. The offset time was 2.5 min (p < 0.05) for PAG and 12.5 min (p < 0.01) for CmPf. The two targets were effective at different stimulation frequencies and were not antagonistic in effect. CONCLUSION: The mechanisms by which stimulation at these two targets produces analgesia are likely to be different. Certain pain qualities may respond more favourably to specific targets. Knowledge of onset and offset times for the targets can guide optimisation of stimulation settings. The use of more than one stimulation target may be beneficial and should be considered in anaesthesia dolorosa patients