RESUMEN
The electron-positron collider DAPhiNE, the Italian Phi factory, has been recently upgraded in order to implement an innovative collision scheme based on large crossing angle, small beam sizes at the crossing point, and compensation of beam-beam interaction by means of sextupole pairs creating a "crab-waist" configuration in the interaction region. Experimental tests of the novel scheme exhibited an increase by a factor of 3 in the peak luminosity of the collider with respect to the performances reached before the upgrade. In this Letter we present the new collision scheme, discuss its advantages, describe the hardware modifications realized for the upgrade, and report the results of the experimental tests carried out during commissioning of the machine in the new configuration and standard operation for the users.
RESUMEN
This study has provided new data on methods for preventing regurgitation and aspiration under general anesthesia, by using parenteral and enteral antacids as premedication in urgent surgery. There is evidence that with 60-minute delay in starting surgery, omeprazole, 40 mg, has the highest alkalizing effect. Second- and third-generation H2-blockers have a persistent and good antacid effect. In emergencies, 30 ml of 3% sodium citrate solution show a rapid and effective antacid effect, which eliminates or drastically reduces the likelihood of aspiration pulmonitis even in case of regurgitation and aspiration of the gastric contents. Based on the findings, the authors have developed a patient preparation protocol for general anesthesia in urgent surgery as the standard for the practical use in general anesthesiology.
Asunto(s)
Anestesia General/métodos , Antiácidos/uso terapéutico , Servicios Médicos de Urgencia , Reflujo Gastroesofágico/prevención & control , Medicación Preanestésica , Aspiración Respiratoria/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anestesia General/efectos adversos , Antiácidos/administración & dosificación , Servicios Médicos de Urgencia/métodos , Servicios Médicos de Urgencia/normas , Femenino , Determinación de la Acidez Gástrica , Humanos , Concentración de Iones de Hidrógeno , Masculino , Persona de Mediana Edad , Medicación Preanestésica/métodos , Medicación Preanestésica/normas , Resultado del TratamientoRESUMEN
The DELSY (Dubna Electron Synchrotron) project is under development at the Joint Institute for Nuclear Research [Arkhipov et al. (2001). Nucl. Instrum. Methods, A467, 57-62; Arkhipov et al. (2001). Nucl. Instrum. Methods, A470, 1-6; Titkova et al. (2000). Proceedings of the Seventh European Particle Accelerator Conference, pp. 702-704]. It is based on an acceleration facility donated to the Joint Institute for Nuclear Research by the Institute for Nuclear and High Energy Physics (NIKHEF, Amsterdam). The NIKHEF accelerator facility consists of the linear electron accelerator MEA, which has an electron energy of 700 MeV, and the electron storage ring AmPS, with a maximum energy of 900 MeV and a beam current of 200 mA. There are three phases to the construction of the DELSY facility. Phase I will be accomplished with the construction of a complex of free-electron lasers covering continuously the spectrum from the far infrared down to the ultraviolet ( approximately 150 nm). Phase II will be accomplished with the commissioning of the storage ring DELSY. Complete commissioning of the DELSY project will take place after finishing Phase III, the construction of an X-ray free-electron laser. This phase is considered as the ultimate goal of the project; it is currently under development and is not described in this paper.