Pigment analysis by Raman microscopy and portable X-ray fluorescence (pXRF) of thirteenth to fourteenth century illuminations and cuttings from Bologna

Non-destructive pigment analysis by Raman microscopy (RM) and portable X-ray fluorescence (pXRF) has been carried out on some Bolognese illuminations and cuttings chosen to represent the beginnings, evolution and height of Bolognese illuminated manuscript production. Dating to the thirteenth and fourteenth centuries and held in a private collection, the study provides evidence for the pigments generally used in this period. The results, which are compared with those obtained for other north Italian artwork, show the developments in usage of artistic materials and technique. Also addressed in this study is an examination of the respective roles of RM and pXRF analysis in this area of technical art history

Evaluating Doppel’s impact on Anxiety and Focus amongst adults with ADHD

Attention Deficit Hyperactivity Disorder (ADHD) is the most commonly diagnosed psychiatric disorder in children. Amongst adults, it is often underdiagnosed and associated with comorbidities including anxiety. This study presents a trial evaluating the efficacy of Doppel, a wrist-worn wearable that provides vibrations linked to one’s heart rate to improve symptoms of anxiety and poor focus amongst young adults with ADHD. Young adults (aged 18–25) used either an active or comparator Doppel for 8 weeks, completing measures of anxiety and focus at baseline, 4 weeks, and 8 weeks. Participants in both groups experienced a reduction in anxiety and an increase in focus across the trial duration. No superiority for vibrations linked to one’s heart rate was found. Whilst the current study cannot determine a specific mechanism of action, the findings provide some promising initial evidence as to the potential for direct-to-consumer digital health products to be useful in symptom management amongst young adults with ADHD

Differential elastic scattering cross sections for 54.9eV positrons incident on helium

Absolute differential elastic scattering cross sections measured with the 3-m, high resolution, time-of-flight spectrometer are presented for 54.9eV positrons incident on He. Five point moving average differential cross sections are plotted against average scattering angles which range from 14 to 36 deg. Also the averages of five differential cross sections which have adjacent values of scattering angle are plotted versus the corresponding averages of the scattering angles. The curve fitted to these data is shaped like the theoretical curve but has its minimum and its maximum at scattering angles that are about 4 deg higher and 15 deg lower respectively than predicted by theory

Spectroscopic measurements of temperature and plasma impurity concentration during magnetic reconnection at the Swarthmore Spheromak Experiment

Electron temperature measurements during counterhelicity spheromak merging studies at the Swarthmore Spheromak Experiment (SSX) [M. R. Brown, Phys. Plasmas 6, 1717 (1999)] are presented. VUV monochromator measurements of impurity emission lines are compared with model spectra produced by the non-LTE excitation kinematics code PRISMSPECT [J. J. MacFarlane et al., in Proceedings of the Third Conference on Inertial Fusion Science and Applications (2004)] to yield the electron temperature in the plasma with 1 µs time resolution. Average T_e is seen to increase from 12 to 19 eV during spheromak merging. Average C III ion temperature, measured with a new ion Doppler spectrometer (IDS) [C. D. Cothran et al., Rev. Sci. Instrum. 77, 063504 (2006)], likewise rises during spheromak merging, peaking at ~22 eV, but a similar increase in T_i is seen during single spheromak discharges with no merging. The VUV emission line measurements are also used to constrain the concentrations of various impurities in the SSX plasma, which are dominated by carbon, but include some oxygen and nitrogen. A burst of soft x-ray emission is seen during reconnection with a new four-channel detector (SXR). There is evidence for spectral changes in the soft x-ray emission as reconnection progresses, although our single-temperature equilibrium spectral models are not able to provide adequate fits to all the SXR data

The relation between Δν\Delta\nu and νmax\nu_{max} for solar-like oscillations

Establishing relations between global stellar parameters and asteroseismic quantities can help improve our understanding of stellar astrophysics and facilitate the interpretation of observations. We present an observed relation between the large frequency separation, $\Delta\nu$, and the frequency of maximum power, $\nu_{max}$. We find that $\Delta\nu$ is proportional to $(\nu_{max})^0.77$, allowing prediction of $\Delta\nu$ to about 15 per cent given $\nu_{max}$. Our result is further supported by established scaling relations for $\Delta\nu$ and $\nu_{max}$ and by extended stellar model calculations, which confirm that $\Delta\nu$ can be estimated using this relation for basically any star showing solar-like oscillations in the investigated range (0.5<M/Msol<4.0).Comment: 5 pages, 8 figures, Letter accepted by MNRA

NGC 6819: testing the asteroseismic mass scale, mass loss, and evidence for products of non-standard evolution

We present an extensive peakbagging effort on Kepler data of $\sim$50 red giant stars in the open star cluster NGC 6819. By employing sophisticated pre-processing of the time series and Markov Chain Monte Carlo techniques we extracted individual frequencies, heights and linewidths for hundreds of oscillation modes. We show that the "average" asteroseismic parameter $\delta\nu_{02}$, derived from these, can be used to distinguish the stellar evolutionary state between the red giant branch (RGB) stars and red clump (RC) stars. Masses and radii are estimated using asteroseismic scaling relations, both empirically corrected to obtain self-consistency as well as agreement with independent measures of distance, and using updated theoretical corrections. Remarkable agreement is found, allowing the evolutionary state of the giants to be determined exclusively from the empirical correction to the scaling relations. We find a mean mass of the RGB stars and RC stars in NGC 6819 to be $1.61\pm0.02\,\textrm{M}_\odot$ and $1.64{\pm}0.02\,\textrm{M}_\odot$, respectively. The difference $\Delta M=-0.03\pm0.01\,\textrm{M}_\odot$ is almost insensitive to systematics, suggesting very little RGB mass loss, if any. Stars that are outliers relative to the ensemble reveal overmassive members that likely evolved via mass-transfer in a blue straggler phase. We suggest that KIC 4937011, a low-mass Li-rich giant, is a cluster member in the RC phase that experienced very high mass-loss during its evolution. Such over- and undermassive stars need to be considered when studying field giants, since the true age of such stars cannot be known and there is currently no way to distinguish them from normal stars.Comment: 21 pages, 11 figure

Proportion of infiltrating IgG-binding immune cells predict for tumour hypoxia

Macrophages can account for up to 50% of tumour mass and secrete many angiogenic factors. Furthermore, tumour hypoxia is thought to play a major role in the activation of macrophages and the regulation of angiogenesis. In this paper, we demonstrate a strong correlation between hypoxia and the recruitment of immune cells binding to IgG in 8 experimental tumours. We provide evidence that IgG binding immune cells in 3 tumour lines are predominately composed of macrophages. Reduced oxygenation may act as a stimulus for recruitment of immune cells to the tumour mass, and the detection of either IgG-positive host cells or macrophages may offer an alternative method for monitoring tumour hypoxia. © 2001 Cancer Research Campaign http://www.bjcancer.co

Temporal heterogeneity in microregional erythrocyte flux in experimental solid tumours.

Using a multichannel laser Doppler system equipped with custom-developed microprobes, we have evaluated real-time fluctuations in microregional blood flow in two experimental murine tumour systems. The results show that in both the sarcoma F and the carcinoma NT over 50% of the microregions evaluated show a fluctuation in red blood cell flux by at least a factor of 2 over a 60 min time period. Approximately 20% of the regions monitored demonstrated a change in flow by a factor of 5 or more. Within the 1 h monitoring period, approximately 20% of the changes were reversed (SaF, 21%; CaNT, 19%). The duration of change for these regions ranged from 6 to 45 min. Similar temporal fluctuations in flow were seen in anaesthetised and unanaesthetised animals, indicating that artifacts due to probe movement were minimal. These findings clearly demonstrate that fluctuations in microregional erythrocyte flux are a common feature of the experimental tumours studied