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1.
Phys Rev Lett ; 103(9): 092302, 2009 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-19792792

RESUMEN

We report results from a search for strangelets (small chunks of strange quark matter) in lunar soil using the Yale WNSL accelerator as a mass spectrometer. We have searched over a range in mass from A = 42 to A = 70 amu for nuclear charges 5, 6, 8, 9, and 11. No strangelets were found in the experiment. For strangelets with nuclear charge 8, a concentration in lunar soil higher than 10(-16) is excluded at the 95% confidence level. The implied limit on the strangelet flux in cosmic rays is the most sensitive to date for the covered range and is relevant to both recent theoretical flux predictions and a strangelet candidate event found by the AMS-01 experiment.

2.
3.
Headache ; 35(2): 79-82, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7737865

RESUMEN

In a noncontrolled study, 23 migraine headache patients were treated with intranasal instillation of 0.4 mL of a 4% lidocaine solution during attacks of varying intensities. Evaluated were pretreatment and posttreatment changes in pain intensity, nausea, and side effects. Posttreatment intensity ratings significantly improved over pretreatment ratings, as determined by a Sandler A analysis (0.077; P < .0005). Migraine attacks were aborted in 12 of 23 patients, of which 8 were completely relieved within 5 minutes. In no case did an aborted attack return to more than a dull level within 24 hours, as determined by follow-up telephone calls. A successful response of migraine attacks to lidocaine treatment was more apt to occur in patients having migraine solely, when compared to migraine patients who also had daily dull headaches; the difference was not significant. Unilateral attacks, however, were significantly more treatment-responsive when compared to bilateral attacks (X2 = 3.85; P = .05). Nausea, associated with migraine attacks in 6 of 12 responders, was similarly aborted by lidocaine in 5 of 6 patients. Other side effects included mild nasal and eye burning of short duration (seconds), and oropharyngeal numbness of approximately 20 minutes' duration. Despite the abrupt and absolute relief of migraine attacks afforded by lidocaine in most of our study patients, its level of efficacy awaits results of double-blind, placebo-controlled studies. Our findings raise new questions regarding the differential pathogenesis of migraine and cluster headache attacks.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Lidocaína/administración & dosificación , Trastornos Migrañosos/tratamiento farmacológico , Administración Intranasal , Adulto , Ensayos Clínicos como Asunto , Femenino , Humanos , Lidocaína/efectos adversos , Lidocaína/uso terapéutico , Masculino , Persona de Mediana Edad , Factores de Tiempo , Resultado del Tratamiento
11.
Bioelectromagnetics ; 11(2): 203-5, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1700714

RESUMEN

The cyclotron-resonance model, which has been suggested as an explanation of a purported enhancement of transport of ions through the membranes of cells exposed to weak, low-frequency-modulated RF fields, is shown to be inconsistent with basic physical principles. Under the conditions of the model, in which the ions are presumed to circulate under the constraint of the earth's magnetic field, the radii of gyration of the ions would approximate 50 m and, thus, are much larger than the cells. Moreover, from general considerations, the collision-damping time of such ions is expected to be less than 10(-10) s, much smaller than the times of the order of 10(-2) s, shown to be necessary if the conditions for low-frequency resonance are to be satisfied.


Asunto(s)
Canales Iónicos/metabolismo , Modelos Biológicos , Matemática
12.
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