| 1. |
- Coron, N., et al.
(författare)
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A Composite Bolometer as a Charged-Particle Spectrometer
- 1985
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 314:6006, s. 75-76
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Tidskriftsartikel (refereegranskat)abstract
- The measurement of radioactivity by direct conversion of nuclear radiation into a temperature rise of a calorimeter is as old as nuclear physics itself. As part of a general programme aiming at a determination of the mass of the electron neutrino, we have designed an improved version of a He-cooled composite diamond bolometer with a monolithic germanium thermistor, developed at the Laboratoire de Physique Stellaire et Planetaire (LPSP)1. Our approach, based on an idea by De Rujula2, is to study the shape, near the upper end-point of the internal bremsstrahlung spectrum in electron-capture β decay. The best nucleus for a precise measurement seems to be 163Ho, for which we have determined3 the Q EC value to be 2.83±0.05 keV. A particularly interesting possibility is to use total absorption spectrometry4 (calorimetry), in which the radioactive holmium forms part of the sensitive volume of the detector. With 5–6-MeV α particles impinging on the diamond wafer of the bolometer, a full-width-at-half-maximum (FWHM) of 36 keV was obtained at a temperature of 1.3 K. The theoretical resolution at 100 mK is a few electron-volts, so this new detection technique should give greatly enhanced energy resolution compared with present solid-state conductors based on charge carrier collection.
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| 2. |
- Fertleman, C. R., et al.
(författare)
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Paroxysmal extreme pain disorder (previously familial rectal pain syndrome)
- 2007
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Ingår i: Neurology. - : Ovid Technologies (Wolters Kluwer Health). - 0028-3878 .- 1526-632X. ; 69:6, s. 586-595
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To describe the clinical phenotype of paroxysmal extreme pain disorder (previously called familial rectal pain syndrome), an autosomal dominant condition recently shown to be a sodium channelopathy involving SCN9A. METHODS: An international consortium of clinicians, scientists, and affected families was formed. Clinical details of all accessible families worldwide were collected, including age at onset, features of attacks, problems between attacks, investigational results, treatments tried, and evolution over time. A validated pain questionnaire was completed by 14 affected individuals. RESULTS: Seventy-seven individuals from 15 families were identified. The onset of the disorder is in the neonatal period or infancy and persists throughout life. Autonomic manifestations predominate initially, with skin flushing in all and harlequin color change and tonic attacks in most. Dramatic syncopes with bradycardia and sometimes asystole are common. Later, the disorder is characterized by attacks of excruciating deep burning pain often in the rectal, ocular, or jaw areas, but also diffuse. Attacks are triggered by factors such as defecation, cold wind, eating, and emotion. Carbamazepine is effective in almost all who try it, but the response is often incomplete. CONCLUSIONS: Paroxysmal extreme pain disorder is a highly distinctive sodium channelopathy with incompletely carbamazepine-sensitive bouts of pain and sympathetic nervous system dysfunction. It is most likely to be misdiagnosed as epilepsy and, particularly in infancy, as hyperekplexia and reflex anoxic seizures.
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