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BACKGROUND Work-related fatigue has been a common problem in the workplaces. The healthcare providers are particularly prone to work-related fatigue, which may jeopardize their own health and put patient safety at risk. Past studies often conducted in a subjective way by using self-report measures completed after work. With the advancement of wearable technology and machine learning (ML), it is possible to utilize the real-time sensor data as the features to build a prediction model of work-related fatigue for clinical staff. OBJECTIVE We sought to apply the ML approaches based on data objectively collected from the smartwatches to construct the prediction models of work-related fatigue for emergency healthcare providers. METHODS This prospective observational study was conducted at the emergency department (ED) of a tertiary teaching hospital from Mar. 10 to Jun. 20, 2021. The ED physicians, nurses, and nurse practitioners were recruited for this study. All participants wore a commercially available smartwatch capable of measuring various physiological data by the embedded sensors during the experiment. Data were synchronized to a private cloud by the smartphone-constructed gateways via Bluetooth protocol. Participants completed the Multidimensional Fatigue Inventory (MFI) web form before and after each of their work shift. The score differences between each pair of work shifts were calculated and labeled. Several tree-based algorithms were used to construct the prediction models of work-related fatigue based on features collected from the smartwatch. The selected features were ranked by using the entropy measures based on information gain theory. Records were split into training/validation and testing sets at a 70-to-30 ratio and the performances were evaluated using area under the curve (AUC) measure of receiver operating characteristic on the test set. RESULTS In total, 110 participants included in this study, contributing to a set of 1542 effective records. Of them, 85 (5.5%) records were labeled as having work-related fatigue when setting the in-between MFI difference of two standard deviations as the threshold. The mean age of the participants was 29.6. Most of the records were collected from nurses (87.7%) and female (77.5%). A union of 31 features were selected to construct the models. For total participants, CatBoost classifier achieved the best performances of AUC (0.838, 95% CI: 0.742 – 0.918) to identify work-related fatigue. By focusing on a subgroup of nurses under 35 years, eXtreme Gradient Boosting (XGBoost) classifier obtained excellent performance of AUC (0.928, 95% CI: 0.839 – 0.991) on the test set in this study. CONCLUSIONS By using features derived from a smartwatch, we successfully built the ML models capable of classifying the risk of work-related fatigue in the ED environment. It is possible to apply such smartwatch-based ML models to predict work-related fatigue and adopt preventive measures for emergency healthcare providers in the future. CLINICALTRIAL None

The Array for Microwave Background Anisotropy is a 7-element interferometer sited on Mauna Loa, Hawaii. The seven 60cm telescopes are mounted on a 6-meter platform, and operates at 3mm wavelength. In October 2006, the telescope was officially dedicated and renamed as the Y. T. Lee AMiBA. During 2007, scientific operations have begun, after a long process of calibration and testing. At the time of this meeting, six clusters of galaxies have been detected and mapped via the inverse Compton scattering of the Cosmic Microwave Background radiation, also known as the Sunyaev-Zel'dovich Effect.

We analyse HST WFC3/$H_{160}$-band observations of a sample of 48 ALMA-detected submillimeter galaxies (SMGs) in the Extended Chandra Deep Field South field, to study their stellar morphologies and sizes. We detect 79$\pm$17% of the SMGs in the $H_{160}$-band imaging with a median sensitivity of 27.8 mag, and most (80%) of the non-detections are SMGs with 870$\mu$m fluxes of $S_{870} < $3 mJy. With a surface brightness limit of $\mu_H \sim $26 mag arcsec$^{-2}$, we find that 82$\pm$9% of the $H_{160}$-band detected SMGs at $z =$ 1-3 appear to have disturbed morphologies, meaning they are visually classified as either irregulars or interacting systems, or both. By determining a S\'ersic fit to the $H_{160}$ surface-brightness profiles we derive a median S\'ersic index of $n = $1.2$\pm$0.3 and a median half-light radius of $r_e = $4.4$^{+1.1}_{-0.5}$ kpc for our SMGs at $z = $1-3. We also find significant displacements between the positions of the $H_{160}$-component and 870$\mu$m emission in these systems, suggesting that the dusty star-burst regions and less-obscured stellar distribution are not co-located. We find significant differences in the sizes and the S\'ersic index between our $z = $2-3 SMGs and $z \sim $2 quiescent galaxies, suggesting a major transformation of the stellar light profile is needed in the quenching processes if SMGs are progenitors of the red-and-dead $z\sim$2 galaxies. Given the short-lived nature of SMGs, we postulate that the majority of the $z = $2-3 SMGs with $S_{870} \gtrsim $2 mJy are early/mid-stage major mergers., Comment: ApJ in press, 32 pages, 13 figures

The Array for Microwave Background Anisotropy is a 7-element interferometer to be sited on Mauna Loa, Hawaii. The seven 1.2m telescopes are mounted on a 6-meter platform, and operates at 3mm wavelength. At the time of this meeting, the telescope is under construction at the Vertex factory in Germany. It is due to be delivered in the middle of 2004. A 2-element prototype instrument has already been deployed to Mauna Loa where initial tests are underway.

Due to the finite-size beam, interferometry observations of the CMB polarization tend to measure a mixture of E and B modes arising from uw-space smearing. We propose an interferometry observation strategy that can disentangle the polarization E and B modes in a clean manner. This strategy employs a similar principle as that of the single-dish observation proposed earlier, but requiring additional linear combinations of signals measured from different baselines. In this work, we consider a hexagonally packed interferometry array as an example to demonstrate the ultility and efficiency of the proposed method. The measurement from a unit cell of equilateral triangular baselines in interferometry measurement is found to be comparable to that from a single dish in single-dish measurements.

Although it has previously been recognized that the CMB polarization measurement on a sky ring is able to separate the B and E-mode patterns, we show that the rotational symmetry of the CMB polarization measurement is indeed unique, in that it enables the B and E modes to be separately measured in a simple and clean manner. The separation of B and E modes can in principle be achieved even with a single-polarization detector of arbitrary beam pattern. Based on this premise, a specific observing strategy is suggested, where the telescope scans along a sky circle with the polarimeter axis always oriented to a fixed direction with respect to the radial direction of the sky circle. The observational strategy for B-mode measurements can further be refined by choosing appropriate beam sizes to suppress the accidental E-mode leakage. We present the expected variances of the measured E and B-mode surface-brightness fluctuations as functions of the sky annulus radius and beam size. The measured peak power is expected to be up to 10% of the total power contained in the CMB polarization fluctuations for both B and E modes. The temperature-polarization, or T-E, correlation can be measured by the present method as well. By adopting this strategy, the AMiBA experiment is expected to detect, in a single sky annulus, a 1\sigma$ B-mode signal in 340 hours.

The Yuan-Tseh Lee Array for Microwave Background Anisotropy (AMiBA) is the first interferometer dedicated to studying the cosmic microwave background (CMB) radiation at 3mm wavelength. The choice of 3mm was made to minimize the contributions from foreground synchrotron radiation and Galactic dust emission. The initial configuration of seven 0.6m telescopes mounted on a 6-m hexapod platform was dedicated in October 2006 on Mauna Loa, Hawaii. Scientific operations began with the detection of a number of clusters of galaxies via the thermal Sunyaev-Zel'dovich effect. We compare our data with Subaru weak lensing data in order to study the structure of dark matter. We also compare our data with X-ray data in order to derive the Hubble constant., Comment: accepted for publication in ApJ (13 pages, 7 figures); a version with high resolution figures available at http://www.asiaa.sinica.edu.tw/~keiichi/upfiles/AMiBA7/pho_highreso.pdf

We present a catalog of 1921 spectroscopic redshifts measured in the fields of the massive galaxy clusters MACSJ0416.1--2403 ($z=0.397$), MACSJ0717.5+3745 ($z=0.546$), and MACSJ1149.5+2223 ($z=0.544$), i.e., three of the four clusters selected by STScI as the targets of the Frontier Fields (FF) initiative for studies of the distant Universe via gravitational lensing. Compiled in the course of the MACS project (Massive Cluster Survey) that detected the FF clusters, this catalog is provided to the community for three purposes: (1) to allow the identification of cluster members for studies of the galaxy population of these extreme systems, (2) to facilitate the removal of unlensed galaxies and thus reduce shear dilution in weak-lensing analyses, and (3) to improve the calibration of photometric redshifts based on both ground- and spacebased observations of the FF clusters., Updated to match the published version. All data available electronically from the online ApJS article, as well as via the Frontier Fields MAST website at http://www.stsci.edu/hst/campaigns/frontier-fields/FF-Data

The CMB polarization E and B tensor patterns possess different parities, much like those in the familiar curl-free and divergence-free vector patterns. It is possible to project the polarization tensor map into a vector map, which consists of the linear superposition of a curl-free and a divergence-free vector field. This map not only allows one to visualize what the E and B modes look like, but it also permits the E–B separation by a topological means. The measured variance of surface brightness for the E and B modes by this topological strategy is presented.

We present an analysis of the structures and dynamics of the merging cluster Abell~1201, which has two sloshing cold fronts around a cooling core, and an offset gas core approximately 500kpc northwest of the center. New Chandra and XMM-Newton data reveal a region of enhanced brightness east of the offset core, with breaks in surface brightness along its boundary to the north and east. This is interpreted as a tail of gas stripped from the offset core. Gas in the offset core and the tail is distinguished from other gas at the same distance from the cluster center chiefly by having higher density, hence lower entropy. In addition, the offset core shows marginally lower temperature and metallicity than the surrounding area. The metallicity in the cool core is high and there is an abrupt drop in metallicity across the southern cold front. We interpret the observed properties of the system, including the placement of the cold fronts, the offset core and its tail in terms of a simple merger scenario. The offset core is the remnant of a merging subcluster, which first passed pericenter southeast of the center of the primary cluster and is now close to its second pericenter passage, moving at ~1000 km/s. Sloshing excited by the merger gave rise to the two cold fronts and the disposition of the cold fronts reveals that we view the merger from close to the plane of the orbit of the offset core., Comment: accepted by ApJ

We examine atmospheric heating by radio active galactic nuclei (AGNs) in distant X-ray clusters by cross correlating clusters selected from the 400 Square Degree (400SD) X-ray Cluster survey with radio sources in the NRAO VLA Sky Survey. Roughly 30% of the clusters show radio emission above a flux threshold of 3 mJy within a projected radius of 250 kpc. The radio emission is presumably associated with the brightest cluster galaxy. The mechanical jet power for each radio source was determined using scaling relations between radio power and cavity (mechanical) power determined for nearby clusters, groups, and galaxies with hot atmospheres containing X-ray cavities. The average jet power of central radio AGNs is approximately 2 x 10{sup 44} erg s{sup -1}. We find no significant correlation between radio power, and hence mechanical jet power, and the X-ray luminosities of clusters in the redshift range 0.1-0.6. This implies that the mechanical heating rate per particle is higher in lower mass, lower X-ray luminosity clusters. The jet power averaged over the sample corresponds to an atmospheric heating of approximately 0.2 keV per particle within R{sub 500}. Assuming the current AGN heating rate does not evolve but remains constant to redshifts of 2, themore » heating rate per particle would rise by a factor of two. We find that the energy injected from radio AGNs contribute substantially to the excess entropy in hot atmospheres needed to break self-similarity in cluster scaling relations. The detection frequency of radio AGNs is inconsistent with the presence of strong cooling flows in 400SD clusters, but does not exclude weak cooling flows. It is unclear whether central AGNs in 400SD clusters are maintained by feedback at the base of a cooling flow. Atmospheric heating by radio AGNs may retard the development of strong cooling flows at early epochs.« less