RESUMEN
Beyond fifth generation (5G) communication systems aim towards data rates in the tera bits per second range, with improved and flexible coverage options, introducing many new technological challenges in the fields of network architecture, signal pro- cessing, and radio frequency front-ends. One option is to move towards cell-free, or distributed massive Multiple-Input Multiple-Output (MIMO) network architectures and highly integrated front-end solutions. This paper presents an outlook on be- yond 5G distributed massive MIMO communication systems, the signal processing, characterisation and simulation challenges, and an overview of the state of the art in millimetre wave antennas and electronics.
RESUMEN
OBJECTIVE: To investigate the prevalence of headache and its association with lifestyle among schoolchildren and to test an intervention programme. DESIGN: A cross-sectional survey of all pupils in the school who were asked to complete a questionnaire about headache and lifestyle factors. SETTING: School health care at an elementary school in Sweden. SUBJECTS: All 344 pupils aged 13-16 years, 170 girls and 174 boys, at senior level answered the questionnaire and were included in the study. MAIN OUTCOME MEASURES: Headache occurring at least once a week. RESULTS: Twenty-two percent had headache at least once a week. The problem was more common among girls than among boys; OR 1.6 (95%CI 1.3-2.1). In girls, headache was associated with smoking; OR 6.6 (CI 1.2-35.5), going to bed later than 11 p.m.; OR 4.4 (CI 1.1-18.0), headache in parents; OR 2.0 (CI 1.0-4.2), and few sports activities; OR 3.0 (CI 1.2-7.5). The only corresponding association in boys was with smoking; OR 12.0 (CI 1.5-101). Headache improved in pupils participating in the programme. CONCLUSIONS: Headache is a common health problem in schoolchildren of both sexes at senior level and shows strong associations with lifestyle factors in girls. Intervention seems to be efficient.
Asunto(s)
Conducta del Adolescente , Cefalea/epidemiología , Estilo de Vida , Estudiantes/psicología , Adolescente , Femenino , Cefalea/etiología , Humanos , Masculino , Prevalencia , Instituciones Académicas , Encuestas y Cuestionarios , Suecia/epidemiologíaRESUMEN
BACKGROUND: Severe contusion of an artery often presents clinical problems in that it affects flow distal to the injury. However, the effect of a contusion on the microvascular flow regulation in the distal part of the limb is still largely unknown. METHODS: A multipoint microelectrode technique was used to assess both tissue oxygenation (PtO2) and microflow (hydrogen clearance) on the skeletal muscle surface in a standard contusion injury to the femoral vessels in rats. RESULTS: A significant increase in and an altered distribution of (PtO2) as well as a reduction in and altered distribution of microflow on the muscle surface distal to the injury was found in all animals (n = 27) compared with the uninjured control leg. These findings could not be reproduced experimentally by sympathectomy or when the adjacent skeletal muscle alone was injured. CONCLUSION: The results suggest that the changes observed distal to the injury are of vascular origin, possibly as a result of endothelial damage at the site of the contusion.
Asunto(s)
Contusiones/sangre , Arteria Femoral/lesiones , Vena Femoral/lesiones , Músculo Esquelético/irrigación sanguínea , Animales , Hipoxia de la Célula , Puntaje de Gravedad del Traumatismo , Pierna , Masculino , Microcirculación , Músculo Esquelético/química , Oxígeno/análisis , Ratas , Ratas Sprague-Dawley , Flujo Sanguíneo RegionalRESUMEN
The effects of a seven-week (11 two-hour sessions) group post-treatment rehabilitation program ('Starting again') for cancer patients were assessed. The program emphasised physical training, information, and training of coping skills. Thirty participants were matched to thirty patients, not wanting to participate (comparison group) and compared in a longitudinal study: before and after the program, and three, six and twelve months after program completion. Program participants had a significantly heavier burden of physical and psychological symptoms at entry than did patients who chose not to participate. More participants reported change of their life-style and habits after the cancer diagnosis than did the comparison group. In comparison with non-participants, participants were more satisfied with information during the entire follow-up, improved more from pre- to post measurement with respect to physical strength and increased their physical training and social activities more.
Asunto(s)
Neoplasias/rehabilitación , Psicoterapia de Grupo , Adulto , Anciano , Femenino , Humanos , Estilo de Vida , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Neoplasias/psicología , Educación y Entrenamiento FísicoRESUMEN
White is a widespread coat color among domestic pig breeds and is controlled by an autosomal dominant gene I. The segregation of this gene was analyzed in a reference pedigree for gene mapping developed by crossing the European wild pig and a Large White domestic breed. The gene for dominant white color was shown to be closely linked to the genes for albumin (ALB) and platelet-derived growth factor receptor alpha (PDGFRA) on chromosome 8. An unexpected phenotype with patches of colored and white coat was observed among the F1 and F2 animals. The segregation data indicated that the phenotype was controlled by a third allele, denoted patch (Ip), most likely transmitted by one of the Large White founder animals. It is shown that the ALB, PDGFRA, I linkage group shares homologies with parts of mouse chromosome 5, human chromosome 4, and horse linkage group II, all of which contain dominant genes for white or white spotting. Candidate genes for the dominant white and patch mutations in the pig are proposed on the basis on these linkage homologies and the recent molecular definition of the dominant white spotting (W) and patch (Ph) mutations in the mouse.