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1.
Nature ; 611(7937): 677-681, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36418451

RESUMEN

Most of the light from blazars, active galactic nuclei with jets of magnetized plasma that point nearly along the line of sight, is produced by high-energy particles, up to around 1 TeV. Although the jets are known to be ultimately powered by a supermassive black hole, how the particles are accelerated to such high energies has been an unanswered question. The process must be related to the magnetic field, which can be probed by observations of the polarization of light from the jets. Measurements of the radio to optical polarization-the only range available until now-probe extended regions of the jet containing particles that left the acceleration site days to years earlier1-3, and hence do not directly explore the acceleration mechanism, as could X-ray measurements. Here we report the detection of X-ray polarization from the blazar Markarian 501 (Mrk 501). We measure an X-ray linear polarization degree ΠX of around 10%, which is a factor of around 2 higher than the value at optical wavelengths, with a polarization angle parallel to the radio jet. This points to a shock front as the source of particle acceleration and also implies that the plasma becomes increasingly turbulent with distance from the shock.

2.
Plants (Basel) ; 12(20)2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37896031

RESUMEN

Roads have the potential to alter local environmental conditions, such as the availability of water and nutrients, and rapidly create suitable habitats for the establishment of both native and non-native plant species, transforming the ecosystems. This is a challenge in Timanfaya National Park and Los Volcanes Natural Park on Lanzarote Island, protected areas that have experienced primary succession after recent volcanic eruptions. In arid ecosystems, changes in abiotic conditions along roadsides might facilitate colonization and plant growth. We analyzed the effect of roads and road type on plant species composition and richness at a spatiotemporal scale. Vascular plant species were systematically recorded at three distances from the road edge on both sides, across fourteen zones in the wet and dry seasons, for three years. Results showed that there were slight differences on species composition depending on the distance to the road edge, as well as on the zones. Species richness was also determined by the interaction of the position, zones, and season, being higher at the road edge. Furthermore, zones with higher traffic intensity showed a higher presence of both native and non-native species. This study highlights the importance of the awareness about the road impacts on species composition by enhancing the colonization capacity of species while facilitating the entry of invasive ones. Good management practices regarding infrastructures in natural protected areas are crucial for the conservation of their unique flora, landscapes, and natural succession processes.

3.
J Physiother ; 65(2): 81-87, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30926400

RESUMEN

QUESTION: In people who have undergone surgical carpal tunnel release, do sensorimotor-based exercises performed on the touchscreen of a tablet device improve outcomes more than a conventional home exercise program prescribed on paper? DESIGN: Randomised, parallel-group trial with concealed allocation, assessor blinding, and intention-to-treat analysis. PARTICIPANTS: Fifty participants within 10 days of surgical carpal tunnel release. INTERVENTION: Each participant was prescribed a 4-week home exercise program. Participants in the experimental group received the ReHand tablet application, which administered and monitored exercises via the touchscreen. The control group was prescribed a home exercise program on paper, as is usual practice in the public hospital system. OUTCOME MEASURES: The primary outcome was functional ability of the hand, reported using the shortened form of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) questionnaire. Secondary outcomes were grip strength, pain intensity measured on a 10-cm visual analogue scale, and dexterity measured with the Nine-Hole Peg Test. Outcomes were measured by a blinded assessor at baseline and at the end of the 4-week intervention period. RESULTS: At Week 4, functional ability improved significantly more in the experimental group than the control group (MD -21, 95% CI -33 to -9) on the QuickDASH score (0 to 100). Although the mean estimates of effect on the secondary outcome also all favoured the experimental group, none reached statistical significance: grip strength (MD 5.6 kg, 95% CI -0.5 to 11.7), pain (MD -1.4 cm, 95% CI -2.9 to 0.1), and dexterity (MD -1.3 seconds, 95% CI -3.7 to 1.1). CONCLUSION: Use of the ReHand tablet application for early rehabilitation after carpal tunnel release is more effective in the recovery of functional ability than a conventional home exercise program. It remains unclear whether there are any benefits in grip strength, pain or dexterity. TRIAL REGISTRATION: ACTRN12618001887268.


Asunto(s)
Síndrome del Túnel Carpiano/rehabilitación , Computadoras de Mano , Terapia por Ejercicio , Terapia Asistida por Computador/instrumentación , Adulto , Síndrome del Túnel Carpiano/cirugía , Evaluación de la Discapacidad , Prueba de Esfuerzo , Femenino , Fuerza de la Mano , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Método Simple Ciego , Interfaz Usuario-Computador
4.
J Nerv Ment Dis ; 194(6): 411-4, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16772857

RESUMEN

Previous research has found substantial relationships between fantasy proneness and schizotypy in adulthood. The aim of the present study is to examine the connections between these constructs in an adolescent sample. A sample of 511 adolescents filled out a measure of fantasy proneness and a measure of psychotic-like phenomena. The factorial pattern for schizotypal traits in adolescents replicate the earlier documented three-factor structure. Also, the full range of schizotypal features was found to be related to imaginative tendencies tapped by fantasy proneness. Finally, joint analysis of fantasy and schizotypy showed that, in adolescents, fantasy converges with magical ideation and the cognitive-perceptual dimension of schizotypy, but diverges from the interpersonal aspects of schizotypy.


Asunto(s)
Fantasía , Inventario de Personalidad/estadística & datos numéricos , Trastorno de la Personalidad Esquizotípica/diagnóstico , Trastorno de la Personalidad Esquizotípica/psicología , Adolescente , Factores de Edad , Análisis Factorial , Femenino , Humanos , Magia , Masculino , Psicometría , Reproducibilidad de los Resultados , Factores de Riesgo , Encuestas y Cuestionarios
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