Context. Open clusters (OCs) are popular tracers of the structure and evolutionary history of the Galactic disc. The OC population is often considered to be complete within 1.8 kpc of the Sun. The ...recent Gaia Data Release 2 (DR2) allows the latter claim to be challenged. Aims. We perform a systematic search for new OCs in the direction of Perseus using precise and accurate astrometry from Gaia DR2. Methods. We implemented a coarse-to-fine search method. First, we exploited spatial proximity using a fast density-aware partitioning of the sky via a k-d tree in the spatial domain of Galactic coordinates, (l, b). Secondly, we employed a Gaussian mixture model in the proper motion space to tag fields quickly around OC candidates. Thirdly, we applied an unsupervised membership assignment method, UPMASK, to scrutinise the candidates. We visually inspected colour-magnitude diagrams to validate the detected objects. Finally, we performed a diagnostic to quantify the significance of each identified over-density in proper motion and in parallax space. Results. We report the discovery of 41 new stellar clusters. This represents an increment of at least 20% of the previously known OC population in this volume of the Milky Way. We also report on the clear identification of NGC 886, an object previously considered an asterism. This study challenges the previous claim of a near-complete sample of OCs up to 1.8 kpc. Our results reveal that this claim requires revision, and a complete census of nearby OCs is yet to be found.
Astrophysical images issued from different instruments and/or spectral bands often require to be processed together, either for fitting or comparison purposes. However each image is affected by an ...instrumental response, also known as point-spread function (PSF), that depends on the characteristics of the instrument as well as the wavelength and the observing strategy. Given the knowledge of the PSF in each band, a straightforward way of processing images is to homogenise them all to a target PSF using convolution kernels, so that they appear as if they had been acquired by the same instrument. We propose an algorithm that generates such PSF-matching kernels, based on Wiener filtering with a tunable regularisation parameter. This method ensures all anisotropic features in the PSFs to be taken into account. We compare our method to existing procedures using measured Herschel/PACS and SPIRE PSFs and simulated JWST/MIRI PSFs. Significant gains up to two orders of magnitude are obtained with respect to the use of kernels computed assuming Gaussian or circularised PSFs. A software to compute these kernels is available at https://github.com/aboucaud/pypher
Context. The Frontier Fields survey is a pioneering observational program aimed at collecting photometric data, both from space (Hubble Space Telescope and Spitzer Space Telescope) and from ...ground-based facilities (VLT Hawk-I), for six deep fields pointing at clusters of galaxies and six nearby deep parallel fields, in a wide range of passbands. The analysis of these data is a natural outcome of the Astrodeep project, an EU collaboration aimed at developing methods and tools for extragalactic photometry and creating valuable public photometric catalogues. Aims. We produce multiwavelength photometric catalogues (from B to 4.5 mu m) for the first two of the Frontier Fields, Abell-2744 and MACS-J0416 (plus their parallel fields). Methods. To detect faint sources even in the central regions of the clusters, we develop a robust and repeatable procedure that uses the public codes Galapagos and Galfit to model and remove most of the light contribution from both the brightest cluster members, and the intra-cluster light. We perform the detection on the processed HST H 160 image to obtain a pure H-selected sample, which is the primary catalogue that we publish. We also add a sample of sources which are undetected in the H 160 image but appear on a stacked infrared image. Photometry on the other HST bands is obtained using SExtractor, again on processed images after the procedure for foreground light removal. Photometry on the Hawk-I and IRAC bands is obtained using our PSF-matching deconfusion code t-phot. A similar procedure, but without the need for the foreground light removal, is adopted for the Parallel fields. Results. The procedure of foreground light subtraction allows for the detection and the photometric measurements of ~2500 sources per field. We deliver and release complete photometric H-detected catalogues, with the addition of the complementary sample of infrared-detected sources. All objects have multiwavelength coverage including B to H HST bands, plus K-band from Hawk-I, and 3.6?4.5 mu m from Spitzer. full and detailed treatment of photometric errors is included. We perform basic sanity checks on the reliability of our results. Conclusions. The multiwavelength photometric catalogues are available publicly and are ready to be used for scientific purposes. Our procedures allows for the detection of outshone objects near the bright galaxies, which, coupled with the magnification effect of the clusters, can reveal extremely faint high redshift sources. Full analysis on photometric redshifts is presented in Paper II.
In species with biparental care, individuals adjust their workload to that of their partner to either compensate or match its investment. Communication within a pair might be crucial for achieving ...this adjustment. Zebra finches, Taeniopygia guttata, form life‐long monogamous pair bonds, in which partners are highly coordinated and both incubate the eggs. When relieving each other during incubation, partners perform a structured call duet at the nest. If this duet functions to coordinate incubation workload, disrupting the pair's usual nest‐relief pattern by delaying the male's return to the nest should affect the structure of the duet. Using domesticated birds breeding in a large aviary, we found that delaying the male's return induced shorter duets with higher call rates. In addition, we tracked the location of individuals with a transponder at the nest and the feeder, and showed that these accelerated duets were associated with an increased haste of the partners to take turns incubating and foraging. Females also spent less time incubating during their subsequent shift, and females' time off‐nest was best predicted by their mate's calling behaviour in the previous duet. Taken together, these results suggest that duets may function as ‘vocal negotiation’ over parental care.
•The upright positioning is associated with a reasonable first positioning and repositioning time when 1 RTT was involved, and a much shorter duration when 2 RTT were involved;•The inter-fraction ...repositioning was on average below 1 mm accuracy for patient setup in upright position for pelvic tumor site;•The intra-fraction motion was within 3 mm for more than 90 % of patients in a 20-minute time frame for patient setup in upright position for pelvic tumor site;•The patient’s subjective assessment of the upright positioning was at least as good, and for some items even better, than in supine position;
Radiotherapy is typically delivered in supine position. However, upright positioning may affect organ volume, positioning, and movement, compared to supine/prone positioning which might have beneficial impacts. In this study, we report patient positioning data in an upright positioning system designed by Leo Cancer Care®.
Sixteen patients with pelvic tumors were included in this study. They had 3 setups in an upright position: an initial setup with acquisition of reference optical images, and 2 repositioning setups. The intra-fraction motion was assessed during two 20-minute chair rotation sessions. The patient comfort in supine and upright position was assessed with a 5-point Likert scale questionnaire.
Eight women and 8 men treated on regular linacs between October 2021 and June 2022 were included. Their median age and weight were 62.5 years (35 to 81 years) and 75.1 kg (41 to 107 kg). The inter-fraction shift means were −0.5 mm (SD = 2.5), −0.4 mm (SD = 1.3) and −0.9 mm (SD = 2.7) in left–right (LR), antero-posterior (AP), and cranio-caudal (CC) directions, respectively. The intrafraction shifts after 20 min were 0.0 mm (SD = 1.5), 0.2 mm (SD = 1.1) and 0.0 mm (SD = 0.3) in LR, CC, and AP directions, respectively. Average global comfort was 4.1 (3 to 5) for the upright position and 3.9 (2 to 5) for the supine position.
In conclusion, the first study on pelvic cancer patients positioned in upright position on a chair is promising, and it opens a potential new direction for the treatment of cancer patients. Evaluation of thoracic and head and neck tumors is ongoing, and imaging with vertical CT is expected to start soon.
Phonophoresis or sonophoresis is the use of ultrasound to increase percutaneous absorption of a drug. The technique has been widely used in sports medicine since the sixties. Controlled studies in ...humans in vivo have demonstrated absence or mild effects of the technique with the parameters currently used (frequency 1–3 MHz, intensity 1–2 W/cm
2, duration 5–10 mins, continuous or pulse mode). However, it was demonstrated in 1995 that administration of macromolecules with conserved biological activity was feasible in animals in vivo using low frequency ultrasound. This led to new research into this method of transdermal administration. The aim of this review is to present the main findings published with low frequency and high frequency ultrasound over the last ten years, and to discuss the respective roles of thermal, cavitational and non-cavitational effects on the reduction of the skin barrier. Particular attention is paid to the biological effects on living skin which might be of importance for tolerance and practical use in humans.
Begging calls are signals of need used by young birds to elicit care from adults. Different theoretical frameworks have been proposed to understand this parent–offspring communication. But ...relationships between parental response and begging intensity, or between begging characteristics and proxies of a young’s need remain puzzling. Few studies have considered the adjustment of nestling begging features to previous experience as a possible explanation of these discrepancies. In this study, we tested the effect of a heterospecific rearing environment on individual developmental trajectories of the acoustic structure of nestling begging calls. Fifty-two zebra finch chicks were fostered either to Bengalese finch or to zebra finch parents, and begging calls were recorded at several stages of nestling development. Acoustic analyses revealed that the development of the spectral features of the begging calls differed between experimental conditions: chicks reared by Bengalese finches produced higher pitched and less broadband begging calls than chicks reared by conspecific parents. Differences were stronger in males than females and were not explained by differences in growth rate. We conclude that nestling begging calls can be plastic in response to social interactions with parents.
Physiological resonance – where the physiological state of a subject generates the same state in a perceiver – has been proposed as a proximate mechanism facilitating pro-social behaviours. While ...mainly described in mammals, state matching in physiology and behaviour could be a phylogenetically shared trait among social vertebrates. Birds show complex social lives and cognitive abilities, and their monogamous pair-bond is a highly coordinated partnership, therefore we hypothesised that birds express state matching between mates. We show that calls of male zebra finches Taeniopygia guttata produced during corticosterone treatment (after oral administration of exogenous corticosterone and during visual separation from the partner) provoke both an increase in corticosterone concentrations and behavioural changes in their female partner compared to control calls (regular calls emitted by the same male during visual separation from the partner only), whereas calls produced during corticosterone treatment by unfamiliar males have no such effect. Irrespective of the caller status (mate/non-mate), calls' acoustic properties were predictive of female corticosterone concentration after playback, but the identity of mate calls was necessary to fully explain female responses. Female responses were unlikely due to a failure of the call-based mate recognition system: in a discrimination task, females perceive calls produced during corticosterone treatment as being more similar to the control calls of the same male than to control calls of other males, even after taking acoustical differences into account. These results constitute the first evidence of physiological resonance solely on acoustic cues in birds, and support the presence of empathic processes.
•First evidence for emotional contagion based on acoustic cues in a songbird•A combination of behavioural and physiological measurements of state matching in birds•Females show a state matching after hearing their partner's calls produced during corticosterone treatment.•Female response is not due to a failure of the recognition system.
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