7 research outputs found

    A Search for Technosignatures Around 11,680 Stars with the Green Bank Telescope at 1.15-1.73 GHz

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    We conducted a search for narrowband radio signals over four observing sessions in 2020-2023 with the L-band receiver (1.15-1.73 GHz) of the 100 m diameter Green Bank Telescope. We pointed the telescope in the directions of 62 TESS Objects of Interest, capturing radio emissions from a total of ~11,680 stars and planetary systems in the ~9 arcminute beam of the telescope. All detections were either automatically rejected or visually inspected and confirmed to be of anthropogenic nature. In this work, we also quantified the end-to-end efficiency of radio SETI pipelines with a signal injection and recovery analysis. The UCLA SETI pipeline recovers 94.0% of the injected signals over the usable frequency range of the receiver and 98.7% of the injections when regions of dense RFI are excluded. In another pipeline that uses incoherent sums of 51 consecutive spectra, the recovery rate is ~15 times smaller at ~6%. The pipeline efficiency affects calculations of transmitter prevalence and SETI search volume. Accordingly, we developed an improved Drake Figure of Merit and a formalism to place upper limits on transmitter prevalence that take the pipeline efficiency and transmitter duty cycle into account. Based on our observations, we can state at the 95% confidence level that fewer than 6.6% of stars within 100 pc host a transmitter that is detectable in our search (EIRP > 1e13 W). For stars within 20,000 ly, the fraction of stars with detectable transmitters (EIRP > 5e16 W) is at most 3e-4. Finally, we showed that the UCLA SETI pipeline natively detects the signals detected with AI techniques by Ma et al. (2023).Comment: 22 pages, 9 figures, submitted to AJ, revise

    Psychosocial correlates of body image and body change behaviors among Malaysian adolescent boys and girls

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    This study used a psychosocial framework to investigate the relationships between BMI, body dissatisfaction, body change behaviors and mental health/behavioral problems amongst a sample of 513 Malay, Indian and Chinese adolescent boys and girls in Malaysia who completed questionnaires assessing these variables. Expected gender differences were not found in relation to body dissatisfaction or engagement in strategies to increase weight, but boys reported greater engagement in strategies to increase muscles. Relationships between body dissatisfaction and engagement in body change behaviors and mental health/behavioral problems varied across race and gender. These findings suggest that the psychosocial framework is a useful way to conceptualise body dissatisfaction and related behaviors, and that caution should be exercised in generalising findings across gender and culture.<br /

    Pluripotent cells in farm animals: state of the art and future perspectives

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