Possible effects of clustering structure in the competition between fast emission processes and compound nucleus decay / Posibles efectos de estructura de agrupamiento en la competencia entre los procesos de emisión rápida y desintegración del núcleo compuesto

Abstract The attention to nuclear clustering has been renewed due to the study of weakly bound nuclei at the drip lines. In particular, clustering structural properties in medium-mass systems have been studied by looking at the competition between the evaporation and pre-equilibrium particle emission in central collisions. Although for light nuclei at an excitation energy close to the particle separation value there are experimental evidence of such structure effects, this is still not the case for heavier systems since the determination of pre-formed clusters within nuclear matter is less obvious. Two systems, leading to the same 81Rb* compound nucleus, have been studied at the same beam velocity 16 AMeV: 16O + 65Cu and 19F + 62Ni. The experiment has been performed using the GARFIELD + RCo detection system installed at the Legnaro National Laboratories.Light charged particles energy distributions and multiplicities have been compared with different statistical and dynamical model calculations. From the first comparison between the two systems a difference in the fast α-decay channel has been evidenced, which can be related to the difference in the projectile structure. Recent data analysis results and comparisons with model calculations are presented in this contribution.

Resumen La atención a la agrupación nuclear se ha renovado debido al estudio de núcleos débilmente unidos en las líneas de goteo. En particular, se han estudiado las propiedades estructurales del agrupamiento en sistemas de masa media al observar la competencia entre la evaporación y la emisión de partículas de preequilibrio en colisiones centrales. Aunque para núcleos ligeros a una energía de excitación cercana al valor de separación de la partícula hay evidencia experimental de tales efectos de estructura, este no es el caso para sistemas más pesados ya que la determinación de agrupamientos preformados dentro de la materia nuclear es menos obvia. Se han estudiado dos sistemas, que conducen al mismo núcleo compuesto 81Rb *, a la misma velocidad de haz 16 AMeV: 16O + 65Cu y 19F + 62Ni. El experimento se ha realizado utilizando el sistema de detección GARFIELD + RCo instalado en los Laboratorios Nacionales Legnaro. Las distribuciones de energía y las multiplicidades de partículas de carga ligera se han comparado con diferentes cálculos de modelos estadísticos y dinámicos. Desde la primera comparación entre los dos sistemas, se ha evidenciado una diferencia en el canal de desintegración α rápida, que se puede relacionar con la diferencia en la estructura del proyectil. En esta contribución se presentan los resultados del análisis de datos recientes y las comparaciones con los cálculos del modelo.

A systematic review of conservative treatment of carpal tunnel syndrome.

OBJECTIVE: To assess the effectiveness of conservative therapy in carpal tunnel syndrome. DATA SOURCES: A computer-aided search of MEDLINE and the Cochrane Collaboration was conducted for randomized controlled trials (RCTs) from January 1985 to May 2006. REVIEW METHODS: RCTs were included if: (1) the patients, with clinically and electrophysiologically confirmed carpal tunnel syndrome, had not previously undergone surgical release, (2) the efficacy of one or more conservative treatment options was evaluated, (3) the study was designed as a randomized controlled trial. Two reviewers independently selected the studies and performed data extraction using a standardized form. In order to assess the methodological quality, the criteria list of the Cochrane Back Review Group for systematic reviews was applied. The different treatment methods were grouped (local injections, oral therapies, physical therapies, therapeutic exercises and splints). RESULTS: Thirty-three RCTs were included in the review. The studies were analysed to determine the strength of the available evidence for the efficacy of the treatment. Our review shows that: (1) locally injected steroids produce a significant but temporary improvement, (2) vitamin B6 is ineffective, (3) steroids are better than non-steroidal anti-inflammatory drugs (NSAIDs) and diuretics, but they can produce side-effects, (4) ultrasound is effective while laser therapy shows variable results, (5) exercise therapy is not effective, (6) splints are effective, especially if used full-time. CONCLUSION: There is: (1) strong evidence (level 1) on efficacy of local and oral steroids; (2) moderate evidence (level 2) that vitamin B6 is ineffective and splints are effective and (3) limited or conflicting evidence (level 3) that NSAIDs, diuretics, yoga, laser and ultrasound are effective whereas exercise therapy and botulinum toxin B injection are ineffective.

Energetics of midvelocity emissions in peripheral heavy ion collisions at Fermi energies.

Peripheral and semiperipheral collisions have been studied in the system 93Nb+93Nb at 38A MeV. The evaporative and midvelocity components of the light charged particle and intermediate mass fragment emissions have been carefully disentangled. In this way it was possible to obtain the average amount not only of charge and mass, but also of energy, pertaining to the midvelocity emission, as a function of an impact parameter estimator. This emission has a very important role in the overall balance of the reaction, as it accounts for a large fraction of the emitted mass and for more than half of the dissipated energy. As such, it may give precious clues on the microscopic mechanism of energy transport from the interaction zone toward the target and projectile remnants.

Intermediate mass fragment emission pattern in peripheral heavy-ion collisions at Fermi energies.

The emission pattern in the v(perp)-v(par) plane of intermediate mass fragments with Z = 3--7 (IMF) has been studied in the collision 116Sn+ 93Nb at 29.5A MeV as a function of the total kinetic energy loss of the reaction. This pattern shows that for peripheral reactions most IMF's are emitted at velocities intermediate between those of the projectile- and target-like products. Coulomb trajectory calculations show that these IMF's are produced in the interaction zone in a short time interval at the end of the target-projectile interaction.

[Evaluation of the locomotor system during pediatric health examinations and elements of kinesitherapy]. / La valutazione dell'apparato locomotore durante i bilanci di salute pediatrici ed elementi di chinesiterapia.

The pediatrician, being a primary health care physician, has the task of bringing the small patient and his parents to the resolution of all those problems which are erroneously referred to a subspecialist. With this in mind, the authors believe that even common orthopedic problems must be evaluated by the pediatrician. He would decide if and when to refer the child to an orthopedic specialist. Certain problems such as congenital hip dysplasia or scoliosis require specific treatment, whereas others (tibial bowing, genu varum-valgum, flatfoot, metatarsus varus) resolve themselves over time. The authors therefore emphasize the role of the pediatrician in preventing any iatrogenic pathology due to inappropriate treatment.

Axial deviations of the spine in blind children.

The authors screened blind children from a special school to determine whether there is any correlation between idiopathic scoliosis and changes in the postural control system induced by blindness. Children with disabilities in addition to blindness, and children under the age of 8 years were excluded. They selected a homogeneous sample of 46 children of whom 39 were congenitally blind and 7 had become blind after birth. The results in the congenitally blind group were highly significant both quantitatively (59% exhibited structural deviations of the spine) and qualitatively. Apart from 2 cases they all exhibited multiple short scoliotic curves with unique characteristics rarely seen in sighted subjects. Despite this, the authors feel unable to make any categorical assertions regarding the possible role played by functional changes in the exterosensory and proprioceptive organs in the pathogenesis of idiopathic scoliosis. They suggest that the development of such multiple small curves in congenital blindness is simply the response of a congenitally deprived mechanism of body development to achieve stable equilibrium in the spine.