Magnetic Confinement of an Ultracold Neutral Plasma.

We demonstrate magnetic confinement of an ultracold neutral plasma (UCNP) created at the null of a biconic cusp, or quadrupole magnetic field. Initially, the UCNP expands due to electron thermal pressure. As the plasma encounters stronger fields, expansion slows and the density distribution molds to the field. UCNP electrons are strongly magnetized over most of the plasma, while ion magnetization is only significant at the boundaries. Observations suggest that electrons and ions are predominantly trapped by magnetic mirroring and ambipolar electric fields, respectively. Confinement times approach 0.5 ms, while unmagnetized plasmas dissipate on a timescale of a few tens of microseconds.

Understanding Heating in Active Region Cores through Machine Learning. I. Numerical Modeling and Predicted Observables.

To adequately constrain the frequency of energy deposition in active region cores in the solar corona, systematic comparisons between detailed models and observational data are needed. In this paper, we describe a pipeline for forward modeling active region emission using magnetic field extrapolations and field-aligned hydrodynamic models. We use this pipeline to predict time-dependent emission from active region NOAA 1158 for low-, intermediate-, and high-frequency nanoflares. In each pixel of our predicted multi-wavelength, time-dependent images, we compute two commonly used diagnostics: the emission measure slope and the time lag. We find that signatures of the heating frequency persist in both of these diagnostics. In particular, our results show that the distribution of emission measure slopes narrows and the mean decreases with decreasing heating frequency and that the range of emission measure slopes is consistent with past observational and modeling work. Furthermore, we find that the time lag becomes increasingly spatially coherent with decreasing heating frequency while the distribution of time lags across the whole active region becomes more broad with increasing heating frequency. In a follow-up paper, we train a random forest classifier on these predicted diagnostics and use this model to classify real observations of NOAA 1158 in terms of the underlying heating frequency.

Modelling nanoflares in active regions and implications for coronal heating mechanisms.

Recent observations from the Hinode and Solar Dynamics Observatory spacecraft have provided major advances in understanding the heating of solar active regions (ARs). For ARs comprising many magnetic strands or sub-loops heated by small, impulsive events (nanoflares), it is suggested that (i) the time between individual nanoflares in a magnetic strand is 500-2000 s, (ii) a weak 'hot' component (more than 10(6.6) K) is present, and (iii) nanoflare energies may be as low as a few 10(23) ergs. These imply small heating events in a stressed coronal magnetic field, where the time between individual nanoflares on a strand is of order the cooling time. Modelling suggests that the observed properties are incompatible with nanoflare models that require long energy build-up (over 10 s of thousands of seconds) and with steady heating.

Community pharmacists as patient advocates: physician attitudes.

OBJECTIVES: To assess physician attitudes toward community pharmacists acting as patient advocates with respect to drug-related matters, and to correlate physician attitudes with physician characteristics and physician-pharmacist interactions. SETTING: State of Utah. PARTICIPANTS: Physicians in family practice, internal medicine, pediatrics, and psychiatry. INTERVENTIONS: Mail survey. MAIN OUTCOME MEASURES: Physician attitudes toward community pharmacists performing 15 patients advocacy activities, as well as physician-pharmacist interaction and respondent demographics. RESULTS: Favorable attitudes were identified for pharmacists monitoring drug use, counseling patients, advising physicians, contacting physicians to discuss patients' pharmacotherapy, and recording over-the-counter product use in patient profiles. Attitudes were less favorable toward pharmacists helping patients manage adverse drug reactions, suggesting drug regimen alterations, providing health screening services, selecting drugs by a protocol, discussing therapeutic equivalents with patients, and changing dosage forms to better suit patient needs. Physician age was negatively correlated with attitude toward a pharmacist aiding a physician in selecting a drug to be prescribed. The helpfulness of physician-pharmacist interactions was positively correlated with physician attitudes. CONCLUSION: From the physician's perspective, the most appropriate areas for expansion of the community pharmacist's role into patient advocacy are in monitoring pharmacotherapy, assisting physicians in coordinating pharmacotherapy, and providing patients with medication information. Physician resistance is more likely in areas where community pharmacists assume a more autonomous role in patient care.