Repeating fast radio bursts with WSRT/Apertif

Context. Repeating fast radio bursts (FRBs) present excellent opportunities to identify FRB progenitors and host environments as well as to decipher the underlying emission mechanism. Detailed studies of repeating FRBs might also hold clues as to the origin of FRBs as a population. Aims. We aim to detect bursts from the first two repeating FRBs, FRB 121102 (R1) and FRB 180814.J0422+73 (R2), and to characterise their repeat statistics. We also want to significantly improve the sky localisation of R2 and identify its host galaxy. Methods. We used the Westerbork Synthesis Radio Telescope to conduct extensive follow-up of these two repeating FRBs. The new phased-array feed system, Apertif, allows one to cover the entire sky position uncertainty of R2 with fine spatial resolution in a single pointing. The data were searched for bursts around the known dispersion measures of the two sources. We characterise the energy distribution and the clustering of detected R1 bursts. Results. We detected 30 bursts from R1. The non-Poissonian nature is clearly evident from the burst arrival times, which is consistent with earlier claims. Our measurements indicate a dispersion measure (DM) of 563.5(2) pc cm(-3), suggesting a significant increase in DM over the past few years. Assuming a constant position angle across the burst, we place an upper limit of 8% on the linear polarisation fraction for the brightest burst in our sample. We did not detect any bursts from R2. Conclusions. A single power-law might not fit the R1 burst energy distribution across the full energy range or widely separated detections. Our observations provide improved constraints on the clustering of R1 bursts. Our stringent upper limits on the linear polarisation fraction imply a significant depolarisation, either intrinsic to the emission mechanism or caused by the intervening medium at 1400 MHz, which is not observed at higher frequencies. The non-detection of any bursts from R2, despite nearly 300 h of observations, implies either a highly clustered nature of the bursts, a steep spectral index, or a combination of the two assuming that the source is still active. Another possibility is that R2 has turned off completely, either permanently or for an extended period of time

Double sampling of a faecal immunochemical test is not superior to single sampling for detection of colorectal neoplasia: a colonoscopy controlled prospective cohort study

<p>Abstract</p> <p>Background</p> <p>A single sampled faecal immunochemical test (FIT) has moderate sensitivity for colorectal cancer and advanced adenomas. Repeated FIT sampling could improve test sensitivity. The aim of the present study is to determine whether any of three different strategies of double FIT sampling has a better combination of sensitivity and specificity than single FIT sampling.</p> <p>Methods</p> <p>Test performance of single FIT sampling in subjects scheduled for colonoscopy was compared to double FIT sampling intra-individually. Test positivity of double FIT sampling was evaluated in three different ways: 1) "one of two FITs+" when at least one out of two measurements exceeded the cut-off value, 2) "two of two FITs+" when both measurements exceeded the cut-off value, 3) "mean of two FITs+" when the geometric mean of two FITs exceeded the cut-off value. Receiver operator curves were calculated and sensitivity of single and the three strategies of double FIT sampling were compared at a fixed level of specificity.</p> <p>Results</p> <p>In 124 of 1096 subjects, screen relevant neoplasia (SRN) were found (i.e. early stage CRC or advanced adenomas). At any cut-off, "two of two FITs+" resulted in the lowest and "one of two FITs+" in the highest sensitivity for SRN (range 35-44% and 42%-54% respectively). ROC's of double FIT sampling were similar to single FIT sampling. At specificities of 85/90/95%, sensitivity of any double FIT sampling strategy did not differ significantly from single FIT (p-values 0.07-1).</p> <p>Conclusion</p> <p>At any cut off, "one of two FITs+" is the most sensitive double FIT sampling strategy. However, at a given specificity level, sensitivity of any double FIT sampling strategy for SRN is comparable to single FIT sampling at a different cut-off value. None of the double FIT strategies has a superior combination of sensitivity and specificity over single FIT.</p

Fluid hydration to prevent post-ERCP pancreatitis in average- to high-risk patients receiving prophylactic rectal NSAIDs (FLUYT trial): Study protocol for a randomized controlled trial

Background: Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) is the most common complication of ERCP and may run a severe course. Evidence suggests that vigorous periprocedural hydration can prevent PEP, but studies to date have significant methodological drawbacks. Importantly, evidence for its added value in patients already receiving prophylactic rectal non-steroidal anti-inflammatory drugs (NSAIDs) is lacking and the cost-effectiveness of the approach has not been investigated. We hypothesize that combination therapy of rectal NSAIDs and periprocedural hydration would significantly lower the incidence of post-ERCP pancreatitis compared to rectal NSAIDs alone in moderate- to high-risk patients undergoing ERCP. Methods: The FLUYT trial is a multicenter, parallel group, open label, superiority randomized controlled trial. A total of 826 moderate- to high-risk patients undergoing ERCP that receive prophylactic rectal NSAIDs will be randomized to a control group (no fluids or normal saline with a maximum of 1.5 mL/kg/h and 3 L/24 h) or intervention group (lactated Ringer's solution with 20 mL/kg over 60 min at start of ERCP, followed by 3 mL/kg/h for 8 h thereafter). The primary endpoint is the incidence of post-ERCP pancreatitis. Secondary endpoints include PEP severity, hydration-related complications, and cost-effectiveness. Discussion: The FLUYT trial design, including hydration schedule, fluid type, and sample size, maximize its power of identifying a potential difference in post-ERCP pancreatitis incidence in patients receiving prophylactic rectal NSAIDs

MIGHTEE-Hi: Evolution of Hi Scaling Relations of Star-forming Galaxies at z &lt; 0.5*

We present the first measurements of H I galaxy scaling relations from a blind survey at z > 0.15. We perform spectral stacking of 9023 spectra of star-forming galaxies undetected in H I at 0.23 < z < 0.49, extracted from MIGHTEE-H I Early Science data cubes, acquired with the MeerKAT radio telescope. We stack galaxies in bins of galaxy properties (stellar mass M *, star formation rateSFR, and specific star formation rate sSFR, with sSFR ≡ M */SFR), obtaining ≳5σ detections in most cases, the strongest H I-stacking detections to date in this redshift range. With these detections, we are able to measure scaling relations in the probed redshift interval, finding evidence for a moderate evolution from the median redshift of our sample z med ~ 0.37 to z ~ 0. In particular, low-M * galaxies ( {\mathrm{log}}_{10}({M}_{* }/{M}_{\odot })\sim 9 )experienceastrongHIdepletion( 0.5dexinlog10(MHI/M⊙) ), while massive galaxies ( {\mathrm{log}}_{10}({M}_{* }/{M}_{\odot })\sim 11$ ) keep their H I mass nearly unchanged. When looking at the star formation activity, highly star-forming galaxies evolve significantly in M H I (f H I, where f H I ≡ M H I/M *) at fixed SFR (sSFR), while at the lowest probed SFR (sSFR) the scaling relations show no evolution. These findings suggest a scenario in which low-M * galaxies have experienced a strong H I depletion during the last ~5 Gyr, while massive galaxies have undergone a significant H I replenishment through some accretion mechanism, possibly minor mergers. Interestingly, our results are in good agreement with the predictions of the SIMBA simulation. We conclude that this work sets novel important observational constraints on galaxy scaling relations

ANALOG-1 ISS - The first part of an analogue mission to guide ESA's robotic moon exploration efforts

The METERON project is a European initiative to prepare for future human-robotic exploration missions to the Moon, Mars and other celestial bodies. The project aims to implement infrastructure and tools to test and evaluate communications, operations and robotic control strategies in the context of future exploration missions. It is in collaboration between three directorates of the European Space Agency (ESA); Human and Robotic Exploration (HRE), Technology, Engineering and Quality (TEC), Operations (OPS). This paper presents the first part of the on-going ANALOG-1 experiment which is the culmination of the METERON project, implementing the knowledge gained in the 12 distinct METERON experiments between 2011 and 2020. These all address aspects of teleoperating a robotic asset from an orbital platform, i.e. technical implementation, user interfaces, autonomy and operations. The ANALOG-1 technology demonstration and operations concept experiment is based upon the surface mission scenario segment of the notional EL3 sample return mission. This segment focuses on the control of a lunar surface robotic asset from the Earth and from the Lunar Gateway. In November 2019, the first part of this experiment was successfully completed from the ISS. It assessed the effectiveness of a state-of-the-art robotic control interface to control a complex mobile robot from orbit, as well as evaluating the scientific interactions, during robotic-assisted geology exploration, between crew in orbit and scientists on the ground. Luca Parmitano drove this robot in a lunar analogue site in the Netherlands, and controlled its arms, while he was on the ISS. For this experiment, a complex control station had been installed on the ISS, including a sigma.7 haptic device. This device allowed the astronaut to feel forces felt by the robotic arm. The experiment demonstrated the advantage of having an immersive control station and high level of robotic dexterity, with Luca finishing all his assigned and secondary geology targets ahead of time. The second part of Analog-1 extends the ISS experiment with a full ground-based analogue, in which further technical experiments and a full mission scenario will be played out. The analogue is in cooperation with the DLR ARCHES space demo mission, and includes a rover operations centre based at ESOC as well as an outdoor lunar analogue site on Mount Etna. The astronaut, in this case, is on ground. We expect to further demonstrate the advantages of a state-of-the art interface for both fully teleoperated and semi-autonomous rover and robotic arm control for lunar missions, in order to guide ESA's Moon exploration efforts

A functional anatomy based kinematic human hand model with simple size adaptation

For the purpose of ergonomic human-machine interaction and geometrical design of hand held haptic devices, a kinematic model that represents the functional anatomy of different human hands is desired. It is the goal of this paper to present a kinematic hand model that is based on human physiology and that is easily adaptable to represent various real human hand sizes. This is achieved by exploiting body proportions to derive finger segment lengths from the hand length. A partial hand model validation, involving index- and middle finger validation using a group of subjects, indicates that the use of body proportions offers a good estimate of finger length from a given hand length. Model estimated fingertip positions over a motion trajectory remain within reasonable limits when compared with experimental data for this subject group. The model is promising for usage in practical situations since only hand length, which is easy to measure or to obtain from literature, is required as an input. Phalange lengths, which are sparsely available from literature and difficult to measure, are generated by the model

The relation between trust and the willingness of enrollees to receive healthcare advice from their health insurer

Abstract Background In a healthcare system based on managed competition, it is important that health insurers are able to channel enrollees to preferred providers. This results in incentives for healthcare providers to improve the quality and reduce the price of care. One of the instruments to guide enrollees to preferred providers is by providing healthcare advice. In order to use healthcare advice as an effective instrument, it is important that enrollees accept the health insurer as a healthcare advisor. As trust in health insurers is not high, this may be an obstacle for enrollees to be receptive to the health insurer’s advice. This study aims to investigate the association between trust in the health insurer and the willingness to receive healthcare advice from the health insurer in the Netherlands. In terms of receiving healthcare advice, we examine both enrollees' willingness to approach the health insurer themselves and their willingness to be approached by the health insurer. Methods In February 2021, a questionnaire was sent to a representative sample of the Dutch population. The questionnaire was completed by 885 respondents (response rate 59%). Respondents were asked about their willingness to receive healthcare advice, and trust in the health insurer was measured using a validated multiple item scale. Logistic regression models were conducted to analyse the results. Results Enrollees with more trust in the health insurer were more willing to approach their health insurer for healthcare advice (OR = 1.07, p = 0.00). In addition, a higher level of trust in the health insurer is significantly associated with the odds that enrollees would like it/really appreciate it if their health insurer actively approached them with healthcare advice (OR = 1.07, p = 0.00). The role of trust in the willingness to receive healthcare advice is not proven to differ between groups with regard to educational levels, health status or age. Conclusions This study confirms that trust plays a role in the willingness to receive healthcare advice from the health insurer. The association between the two emphasizes the importance to increase enrollees’ trust in the health insurer. As a result, health insurers may be better able to fulfil their role as healthcare advisor

To what degree are health insurance enrollees in the Netherlands aware of the restrictive conditions attached to their policies?

BACKGROUND: Within the Dutch healthcare system of managed competition, health insurers can contract healthcare providers selectively. Enrollees who choose a health insurance policy with restrictive conditions will have to make a co-payment if they consult a non-contracted provider. This study aims to gain insight into enrollees' awareness of the conditions of such health insurance policies. METHODS: In August 2020, an online questionnaire was sent out via health insurers to their enrollees with restrictive health plans. In total 13,588 enrollees responded. RESULTS: One fifth of the respondents appeared to be totally unfamiliar with the policy conditions. Men, younger people, people with a low level of education, a lower income, a poorer health status and non-care users were found to be less familiar with the conditions. Of those who have been in the situation that they wanted to visit a healthcare provider whose care was not fully reimbursed, 62% went to that provider. Of those who had to pay extra because hospital care was not fully reimbursed, 62% did not know this in advance and 30% indicated that paying extra was a serious problem. CONCLUSIONS: Not all enrollees who choose a policy with restrictive conditions are aware of the consequences of receiving care from non-contracted providers. Increased awareness among enrollees will benefit the functioning of the healthcare system based on managed competition