L-edge spectroscopy of dilute, radiation-sensitive systems using a transition-edge-sensor array.

We present X-ray absorption spectroscopy and resonant inelastic X-ray scattering (RIXS) measurements on the iron L-edge of 0.5 mM aqueous ferricyanide. These measurements demonstrate the ability of high-throughput transition-edge-sensor (TES) spectrometers to access the rich soft X-ray (100-2000 eV) spectroscopy regime for dilute and radiation-sensitive samples. Our low-concentration data are in agreement with high-concentration measurements recorded by grating spectrometers. These results show that soft-X-ray RIXS spectroscopy acquired by high-throughput TES spectrometers can be used to study the local electronic structure of dilute metal-centered complexes relevant to biology, chemistry, and catalysis. In particular, TES spectrometers have a unique ability to characterize frozen solutions of radiation- and temperature-sensitive samples.

Soft X-ray spectroscopy with transition-edge sensors at Stanford Synchrotron Radiation Lightsource beamline 10-1.

We present results obtained with a new soft X-ray spectrometer based on transition-edge sensors (TESs) composed of Mo/Cu bilayers coupled to bismuth absorbers. This spectrometer simultaneously provides excellent energy resolution, high detection efficiency, and broadband spectral coverage. The new spectrometer is optimized for incident X-ray energies below 2 keV. Each pixel serves as both a highly sensitive calorimeter and an X-ray absorber with near unity quantum efficiency. We have commissioned this 240-pixel TES spectrometer at the Stanford Synchrotron Radiation Lightsource beamline 10-1 (BL 10-1) and used it to probe the local electronic structure of sample materials with unprecedented sensitivity in the soft X-ray regime. As mounted, the TES spectrometer has a maximum detection solid angle of 2 × 10-3 sr. The energy resolution of all pixels combined is 1.5 eV full width at half maximum at 500 eV. We describe the performance of the TES spectrometer in terms of its energy resolution and count-rate capability and demonstrate its utility as a high throughput detector for synchrotron-based X-ray spectroscopy. Results from initial X-ray emission spectroscopy and resonant inelastic X-ray scattering experiments obtained with the spectrometer are presented.

The enigma of rosacea.

This short paper reviews the nature of rosacea emphasizing the possibility of a solar cause. The sites of involvement and the physical signs of rosacea including the flushing, the erythema and the telangiectasia as well as the intermittent episodes of inflammation with swelling and papules may all be explained by UVR induced damage to dermal connective tissue. The dermal damage permits vaso-dilation and vascular pooling.

Voltage-Controlled Interfacial Layering in an Ionic Liquid on SrTiO3.

One prominent structural feature of ionic liquids near surfaces is formation of alternating layers of anions and cations. However, how this layering responds to an applied potential is poorly understood. We focus on the structure of 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl) trifluorophosphate (BMPY-FAP) near the surface of a strontium titanate (SrTiO3) electric double-layer transistor. Using X-ray reflectivity, we show that at positive bias the individual layers in the ionic liquid double layer thicken and the layering persists further away from the interface. We model the reflectivity using a modified distorted crystal model with alternating cation and anion layers, which allows us to extract the charge density and the potential near the surface. We find that the charge density is strongly oscillatory with and without applied potential and that with an applied gate bias of 4.5 V the first two layers become significantly more cation rich than at zero bias, accumulating about 2.5 × 10(13) cm(-2) excess charge density.

A calcium antagonist vs a non-calcium antagonist hypertension treatment strategy for patients with coronary artery disease. The International Verapamil-Trandolapril Study (INVEST): a randomized controlled trial.

CONTEXT: Despite evidence of efficacy of antihypertensive agents in treating hypertensive patients, safety and efficacy of antihypertensive agents for coronary artery disease (CAD) have been discerned only from subgroup analyses in large trials. OBJECTIVE: To compare mortality and morbidity outcomes in patients with hypertension and CAD treated with a calcium antagonist strategy (CAS) or a non-calcium antagonist strategy (NCAS). DESIGN, SETTING, AND PARTICIPANTS: Randomized, open label, blinded end point study of 22 576 hypertensive CAD patients aged 50 years or older, which was conducted September 1997 to February 2003 at 862 sites in 14 countries. INTERVENTIONS: Patients were randomly assigned to either CAS (verapamil sustained release) or NCAS (atenolol). Strategies specified dose and additional drug regimens. Trandolapril and/or hydrochlorothiazide was administered to achieve blood pressure goals according to guidelines from the sixth report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI) of less than 140 mm Hg (systolic) and less than 90 mm Hg (diastolic); and less than 130 mm Hg (systolic) and less than 85 mm Hg (diastolic) if diabetes or renal impairment was present. Trandolapril was also recommended for patients with heart failure, diabetes, or renal impairment. MAIN OUTCOME MEASURES: Primary: first occurrence of death (all cause), nonfatal myocardial infarction, or nonfatal stroke; other: cardiovascular death, angina, adverse experiences, hospitalizations, and blood pressure control at 24 months. RESULTS: At 24 months, in the CAS group, 6391 patients (81.5%) were taking verapamil sustained release; 4934 (62.9%) were taking trandolapril; and 3430 (43.7%) were taking hydrochlorothiazide. In the NCAS group, 6083 patients (77.5%) were taking atenolol; 4733 (60.3%) were taking hydrochlorothiazide; and 4113 (52.4%) were taking trandolapril. After a follow-up of 61 835 patient-years (mean, 2.7 years per patient), 2269 patients had a primary outcome event with no statistically significant difference between treatment strategies (9.93% in CAS and 10.17% in NCAS; relative risk [RR], 0.98; 95% confidence interval [CI], 0.90-1.06). Two-year blood pressure control was similar between groups. The JNC VI blood pressure goals were achieved by 65.0% (systolic) and 88.5% (diastolic) of CAS and 64.0% (systolic) and 88.1% (diastolic) of NCAS patients. A total of 71.7% of CAS and 70.7% of NCAS patients achieved a systolic blood pressure of less than 140 mm Hg and diastolic blood pressure of less than 90 mm Hg. CONCLUSION: The verapamil-trandolapril-based strategy was as clinically effective as the atenolol-hydrochlorothiazide-based strategy in hypertensive CAD patients.

Validating electronic source data in clinical trials.

The clinical trials industry relies heavily on paper-based source documents as the foundation for the collection of its clinical research data from human subjects and medical records. This focus on paper documents has been prevalent throughout the history of clinical trials conduct, even as computing solutions advanced throughout the past 20 years. With the advent of additional electronic capabilities recently with the growth of Internet-based products to enhance business operations in many fields, the clinical trials industry remains uniquely behind most other industries in electronic technology adoptions. Valid reasons exist for the slow growth of technology adoptions in clinical trial activities, but there are now discussions about how to use technology more effectively in clinical trial conduct. One area of enhanced clinical trial conduct is believed to be available by moving from paper-based source documents to electronic source documents, that is, eliminating paper from clinical data capture, and collecting the information initially in a computer system. An important concern in moving to electronic source data is the validation of such data. This paper summarizes the history of clinical data capture through paper and electronic advancements to date and identifies three reasons for the slow movement to more electronic source data. The paper then illustrates two methods for the validation of electronic source data.