The interaction between practice and performance pressure on the planning and control of fast target directed movement

Pressure to perform often results in decrements to both outcome accuracy and the kinematics of motor skills. Furthermore, this pressure-performance relationship is moderated by the amount of accumulated practice or the experience of the performer. However, the interactive effects of performance pressure and practice on the underlying processes of motor skills are far from clear. Movement execution involves both an offline pre-planning process and an online control process. The present experiment aimed to investigate the interaction between pressure and practice on these two motor control processes. Two groups of participants (control and pressure; N = 12 and 12, respectively) practiced a video aiming amplitude task and were transferred to either a non-pressure (control group) or a pressure condition (pressure group) both early and late in practice. Results revealed similar accuracy and movement kinematics between the control and pressure groups at early transfer. However, at late transfer, the introduction of pressure was associated with increased performance compared to control conditions. Analysis of kinematic variability throughout the movement suggested that the performance increase was due to participants adopting strategies to improve movement planning in response to pressure reducing the effectiveness of the online control system

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Localization and broadband follow-up of the gravitational-wave transient GW150914

A gravitational-wave (GW) transient was identified in data recorded by the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) detectors on 2015 September 14. The event, initially designated G184098 and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimates of the time, significance, and sky location of the event were shared with 63 teams of observers covering radio, optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter we describe the low-latency analysis of the GW data and present the sky localization of the first observed compact binary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-ray Coordinates Network circulars, giving an overview of the participating facilities, the GW sky localization coverage, the timeline, and depth of the observations. As this event turned out to be a binary black hole merger, there is little expectation of a detectable electromagnetic (EM) signature. Nevertheless, this first broadband campaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broad capabilities of the transient astronomy community and the observing strategies that have been developed to pursue neutron star binary merger events. Detailed investigations of the EM data and results of the EM follow-up campaign are being disseminated in papers by the individual teams

Localization and broadband follow-up of the gravitational-wave transient GW150914

A gravitational-wave transient was identified in data recorded by the Advanced LIGO detectors on 2015 September 14. The event candidate, initially designated G184098 and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimates of the time, significance, and sky location of the event were shared with 63 teams of observers covering radio, optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter we describe the low-latency analysis of the gravitational wave data and present the sky localization of the first observed compact binary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-ray Coordinates Network Circulars, giving an overview of the participating facilities, the gravitational wave sky localization coverage, the timeline and depth of the observations. As this event turned out to be a binary black hole merger, there is little expectation of a detectable electromagnetic signature. Nevertheless, this first broadband campaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broad capabilities of the transient astronomy community and the observing strategies that have been developed to pursue neutron star binary merger events. Detailed investigations of the electromagnetic data and results of the electromagnetic follow-up campaign will be disseminated in the papers of the individual teams

ApoB48-Lipoproteins Are Associated with Cardiometabolic Risk in Adolescents with and without Polycystic Ovary Syndrome

Context: Adolescents with polycystic ovary syndrome (PCOS) have increased incidence of cardiometabolic risk factors including dyslipidemia. Atherogenic apolipoprotein (apo) B-lipoprotein remnants are associated with increased cardiovascular disease (CVD) risk. Objective: The aim of this study was to determine the concentrations of fasting plasma apoB-lipoprotein remnants, apoB48 and apoB100, and their association with cardiometabolic risk factors and androgen indices in adolescent girls with and without PCOS. Design setting and participants: Participants (n = 184) aged 17 years were recruited in the Menstruation in Teenagers Study from the Western Australian Pregnancy Cohort (Raine) Study. The main outcome measures: Fasting plasma apo-B48 and -B100 lipoprotein remnant concentrations in adolescent girls with and without PCOS. Results: Fasting plasma apoB48-lipoprotein remnants but not apoB100-lipoprotein remnants were elevated in adolescent girls with increased cardiometabolic risk compared with those with lower cardiometabolic risk (13.91 ± 5.06 vs 12.09 ± 4.47 µg/mL, P < .01). ApoB48-lipoprotein remnants were positively correlated with fasting plasma triglycerides (b = .43, P < .0001). The prevalence of increased cardiometabolic risk factors was 2-fold higher in those diagnosed with PCOS (35.3%) than in those without PCOS (16.3%).Conclusion: Adolescents with PCOS have a 2-fold higher incidence of cardiometabolic risk factors than those without PCOS. Fasting apoB48-lipoprotein remnants are elevated in adolescent girls with a high prevalence of cardiometabolic risk factors