A comparison of SNS internal and external antenna source performance with and without cesium.

Experiments comparing an internal and an external antenna H source at the Spallation Neutron Source with and without cesium revealed key performance differences which provide insight to the source physics and will guide the development of an RF H source at the ISIS Neutron Source. RF power sweeps were taken for each of these cases, for which the total charge, electron to H ratio, and H extracted per kW are all studied and plotted. At around 40 kW and typical hydrogen flow and cooling parameters, cesiated sources output 35 mA square beam pulses where uncesiated sources output 15 mA.

Upgrading the LANSCE accelerator with a SNS RF-driven H ion source.

The LANSCE accelerator is currently powered by a filament-driven, biased converter-type H ion source that operates at 10%, the highest plasma duty factor for this type of source, using only ∼2.2 SCCM of H. The ion source needs to be replaced every 4 weeks, which takes up to 4 days.

Record productions establish RF-driven sources as the standard for generating high-duty-factor, high-current H beams for accelerators (Winner of the ICIS 2017 Brightness Award).

The Spallation Neutron Source operates reliably at 1.2 MW and will gradually ramp to 1.4 MW.

Recent performance of the SNS H(-) ion source and low-energy beam transport system.

Recent measurements of the H(-) beam current show that SNS is injecting about 55 mA into the RFQ compared to ∼45 mA in 2010. Since 2010, the H(-) beam exiting the RFQ dropped from ∼40 mA to ∼34 mA, which is sufficient for 1 MW of beam power. To minimize the impact of the RFQ degradation, the service cycle of the best performing source was extended to 6 weeks.

Radiographic diagnosis and differentiation of an aggressive angiomyxoma in a male patient.

Aggressive angiomyxoma is a rare soft-tissue tumor which usually occurs in female patients of reproductive age. Its occurrence in men is even more unusual and as illustrated in this case the difference between pathology suggested by a physical examination and its actual extent can be quite striking. We present a case report of an 81-year-old man with the typical MRI appearances of a pelvic aggressive angiomyxoma, describe imaging and histopathologic features of this rarely seen locally infiltrative neoplasm and also discuss therapeutic options for patients with an aggressive angiomyxoma.

Producing persistent, high-current, high-duty-factor H- beams for routine 1 MW operation of Spallation Neutron Source (invited).

Since 2009, the Spallation Neutron Source (SNS) has been producing neutrons with ion beam powers near 1 MW, which requires the extraction of ∼50 mA H(-) ions from the ion source with a ∼5% duty factor. The 50 mA are achieved after an initial dose of ∼3 mg of Cs and heating the Cs collar to ∼170 °C. The 50 mA normally persist for the entire 4-week source service cycles.

Spallation neutron source saddle antenna H- ion source project.

In this project we are developing an H(-) source which will synthesize the most important developments in the field of negative ion sources to provide high current, high brightness, good lifetime, high reliability, and high power efficiency. We describe two planned modifications to the present spallation neutron source external antenna source in order to increase the plasma density near the output aperture: (1) replacing the present 2 MHz plasma-forming solenoid antenna with a 13 MHz saddle-type antenna and (2) replacing the permanent multicusp magnetic system with a weaker electromagnet.

GLP-1 receptor expression in human tumors and human normal tissues: potential for in vivo targeting.

Unlabelled: Peptide hormone receptors overexpressed in human tumors, such as somatostatin receptors, can be used for in vivo targeting for diagnostic and therapeutic purposes. A novel promising candidate in this field is the GLP-1 receptor, which was recently shown to be massively overexpressed in gut and lung neuroendocrine tumors--in particular, in insulinomas. Anticipating a major development of GLP-1 receptor targeting in nuclear medicine, our aim was to evaluate in vitro the GLP-1 receptor expression in a large variety of other tumors and to compare it with that in nonneoplastic tissues.

Wearable Digital Speech Processor for Cochlear Implants Using a TMS320C25.

Based on a single-chip DSP (TMS320C25, Texas Instruments) a programmable battery-operated sound processor with a digital encoder interface for the Nucleus-22 cochlear implant (CI) was built. The number of quasi-simultaneously addressed electrodes is only limited by the selected pulse width and the maximum rate of stimulation and can be as high as 10 electrodes at 300 Hz repetition rate. Implementation of various processing strategies (formant or channel vocoder, filterbank, zero crossings, etc.