The TSIS-1 Hybrid Solar Reference Spectrum.

We present a new solar irradiance reference spectrum representative of solar minimum conditions between solar cycles 24 and 25. The Total and Spectral Solar Irradiance Sensor-1 (TSIS-1) Hybrid Solar Reference Spectrum (HSRS) is developed by applying a modified spectral ratio method to normalize very high spectral resolution solar line data to the absolute irradiance scale of the TSIS-1 Spectral Irradiance Monitor (SIM) and the CubeSat Compact SIM (CSIM). The high spectral resolution solar line data are the Air Force Geophysical Laboratory ultraviolet solar irradiance balloon observations, the ground-based Quality Assurance of Spectral Ultraviolet Measurements In Europe Fourier transform spectrometer solar irradiance observations, the Kitt Peak National Observatory solar transmittance atlas, and the semi-empirical Solar Pseudo-Transmittance Spectrum atlas. The TSIS-1 HSRS spans 202-2730 nm at 0.01 to ∼0.001 nm spectral resolution with uncertainties of 0.3% between 460 and 2365 nm and 1.3% at wavelengths outside that range.

Validation in a community hospital setting of a clinical rule to predict preserved left ventricular ejection fraction in patients after myocardial infarction.

BACKGROUND: A previous study showed that patients with previous myocardial infarction (MI) who meet 4 simple clinical and/or electrocardiographic criteria have a left ventricular ejection fraction (LVEF) of 40% or greater, with a positive predictive value of 98%. The objective of this study was to validate this clinical rule in the community hospital setting. METHODS: Retrospective chart review in a 330-bed community hospital. Two hundred thirteen consecutive patients with MI were identified between June 1, 1993, and March 31, 1995. Left ventricular ejection fraction was predicted in a blinded fashion by means of the clinical rule before the actual LVEF test was reviewed. RESULTS: We identified 213 patients admitted with the primary discharge diagnosis of acute MI. All patients met standard clinical and enzymatic definitions for acute MI and had at least 1 measure of LVEF, such as echocardiography, ventricular angiography, or gated blood pool scan. The clinical rule predicted that 83 patients (39.0%) would have an LVEF of 40% or greater. Of these 83 patients, 71 had an ejection fraction of 40% or greater, for a positive predictive value of 86%. Of the 12 patients who were incorrectly predicted to have a preserved LVEF, 6 (50%) had an index non-Q-wave anterior MI (P<.001). Reanalyzing the patient population with a fifth variable (anterior non-Q-wave MI) added to the original 4 variables increased the positive predictive value to 91%. CONCLUSION: This simple clinical prediction rule has a positive predictive value of 86% when applied in the community hospital setting. Patients with anterior non-Q-wave MI may be 1 group in whom the rule is inaccurate, and expanding the clinical rule to 5 variables may increase the positive predictive value. When a technology-based assessment of left ventricular function is considered in patients after an MI, this prediction rule may allow for a more cost-effective patient selection, and as many as 40% of patients who have had acute MIs may require no testing at all.

Culture, communication and service quality in health care administration: a tale of two hospitals.

This paper reports the results of a qualitative cross-case analysis of two medium-sized Australian general hospitals moving to a new era of service quality management. The analysis was based on a model of perceptions of organisational culture, communication and quality of patient care. Results showed that the prevailing culture at the two hospitals was quite different, but there was consistency in the relationships between the study variables. In particular, perceptions of culture and communication had an impact on perceptions of quality of care. The results are discussed within the context of previously reported findings.

Decoherence-driven cooling of a degenerate spinor Bose gas.

We investigate the relationship between the coherence of a partially Bose-condensed spinor gas and its temperature. We observe cooling of the normal component driven by decoherence as well as the effect of temperature on decoherence rates.

Normal-superfluid interaction dynamics in a spinor bose gas.

Coherent behavior of spinor Bose-Einstein condensates is studied in the presence of a significant uncondensed (normal) component. Normal-superfluid exchange scattering leads to near-perfect local alignment between the spin fields of the two components. We observe that, through this spin locking, spin-domain formation in the condensate is vastly accelerated as the spin populations in the condensate are entrained by large-amplitude spin waves in the normal component.

Observation of anomalous spin-state segregation in a trapped ultracold vapor.

We observe counterintuitive spin segregation in an inhomogeneous sample of ultracold, noncondensed rubidium atoms in a magnetic trap. We use spatially selective microwave spectroscopy to verify a model that accounts for the differential forces on two internal spin states. In any simple understanding of the cloud dynamics, the forces are far too small to account for the dramatic transient spin polarizations observed. The underlying mechanism remains to be elucidated.

Early ambulation following 6 French diagnostic left heart catheterization: a prospective randomized trial.

Outpatient cardiac catheterization is frequently performed, but the optimal recovery time after sheath removal has not been defined. Left heart catheterization was performed via the femoral artery utilizing 6 French catheters on 323 outpatients. One hundred thirty-five patients were randomized to ambulate at a mean of 2.5 hr (group 1) after puncture site compression, whereas 188 patients were randomized to ambulate at a mean of 4.1 hr (group 2). Telephone follow-up occurred within 48 hr. A small hematoma (< 5 cm) occurred in 2 (1.6%) patients in group 1 and in 4 (2.4%) patients in group 2. These results indicate that it is safe to ambulate patients 2.5 hr following 6 French diagnostic heart catheterization.

Spatial resolution of spin waves in an ultracold gas.

We present the first spatially resolved images of spin waves in a gas. The complete longitudinal and transverse spin field as a function of time and space is reconstructed. Frequencies and damping rates for a standing-wave mode are extracted and compared with theory.