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Source classifications, stellar masses and star formation rates are presented for 80,000 radio sources from the first data release of the Low Frequency Array Two-metre Sky Survey (LoTSS) Deep Fields, which represents the widest deep radio survey ever undertaken. Using deep multi-wavelength data spanning from the ultraviolet to the far-infrared, spectral energy distribution (SED) fitting is carried out for all of the LoTSS-Deep host galaxies using four different SED codes, two of which include modelling of the contributions from an active galactic nucleus (AGN). Comparing the results of the four codes, galaxies that host a radiative AGN are identified, and an optimised consensus estimate of the stellar mass and star-formation rate for each galaxy is derived. Those galaxies with an excess of radio emission over that expected from star formation are then identified, and the LoTSS-Deep sources are divided into four classes: star-forming galaxies, radio-quiet AGN, and radio-loud high-excitation and low-excitation AGN. Ninety-five per cent of the sources can be reliably classified, of which more than two-thirds are star-forming galaxies, ranging from normal galaxies in the nearby Universe to highly-starbursting systems at z>4. Star-forming galaxies become the dominant population below 150-MHz flux densities of about 1 mJy, accounting for 90 per cent of sources at a 150-MHz flux density of 100 microJy. Radio-quiet AGN comprise around 10 per cent of the overall population. Results are compared against the predictions of the SKADS and T-RECS radio sky simulations, and improvements to the simulations are suggested., Accepted for publication in MNRAS. Catalogues available at www.lofar-surveys.org/deepfields.html. 27 pages

This work aimed to estimate the distribution of the electric field generated by a combined cerebellar and frontal transcranial direct current stimulation (tDCS) for treatment-resistant depression using electromagnetics computational techniques applied to a realistic head human model. Results showed that the stronger electric fields occur mainly in the cerebellum and in DLPFC areas, where the two pairs of electrodes were applied. Furthermore, the study demonstrated that the simultaneous use of the two pairs of electrodes did not imply a lower effectiveness of the tDCS technique, in fact the electric field distributions in the primarily targets of the anatomical regions (i.e., cerebellum and DLPFC) were very similar to when the pairs of electrodes were applied separately.

This study is based on the quantification of the influence of the presence of gold nanoparticles (Au NPs), of their geometry and their distance from cell membrane during time-varying electromagnetic fields cell membrane permeabilization on the pores opening dynamics. Results showed that the combined use of Au NPs and time-varying magnetic field can improve significantly the permeabilization of cell membrane. The presence of Au NPs allowed to reach transmembrane potential values enabling the cell membrane permeabilization only when placed at very short distance, equal to 20 nm. Both geometry and variability of the positioning in proximity of the cell membrane showed a strong influence on the probability of enabling pores opening. Clinical Relevance- This study provides a better comprehension about the mechanisms, still not completely understood, underlying cell membrane permeabilization by combining Au NPs and time-varying magnetic fields.

Context. Hyper-luminous infrared galaxies (HLIRGs) are among the most extreme systems in the Universe. With infrared (IR) luminosities of LIR > 1013 L⊙ they can have IR-derived star formation rates (SFRs) exceeding 103 M⊙ yr−1. Theoretical models have a hard time reproducing the observed number densities of such extreme star-forming systems. It is known that at least part of the population harbours active galactic nuclei (AGNs), but their prevalence and relative contribution to the IR output is still debated. Assessing this is further complicated by the heavy dust obscuration. Aims. We aim to investigate the HLIRG population in the Lockman Hole field to assess whether they are truly highly star-bursting systems or whether notable AGN activity is present. A substantial AGN population could help resolve the tension between the HLIRG number densities obtained from observations and predicted by galaxy formation models by lowering the amount of truly extremely star-forming galaxies. Methods. Starting from a highly complete Herschel-selected sample, we made use of recent wide-field sub-arcsecond 144 MHz International LOFAR Telescope (ILT) observations of the Lockman Hole field to probe AGN activity in HLIRGs in a dust-unobscured way. AGN presence was deduced through means of the brightness temperature (Tb). Brightness temperature measurements were made to determine the fraction of HLIRGs harbouring a radio AGN. This identification was then compared to the classification based on spectral energy distribution (SED) fitting based identification from the LOFAR Deep Fields project, the radio-excess q and IRAC infrared colours. Results. We detect 33% of previously identified HLIRGs at sub-arcsecond resolution. All but one of the detected sources is found to exceed the Tb threshold for pure star formation, showing 98% of detections to contain a radio AGN, even though lower-resolution observations had classified them as star-forming galaxies (SFGs). The remaining source is concluded to be consistent with having no AGN activity. All of the sources in our sample that were previously classified as radio AGNs, radio-quiet AGNs or those that were unclassified were detected as high-Tb objects (16% of the total sample or 47% of the detected sub-arcsecond detections). In addition, we identify AGNs through Tb measurements in 20% of sources that were classified as SFGs through SED fitting, raising the overall fraction of AGNs in the total sample from 16% to 32%. AGNs identified through brightness temperature measurements are also found to be more likely to be mid-IR AGNs. Conclusions. 98% of our detected sources are found to likely host radio-AGNs, raising the number of identified AGNs among the HLIRG population in this field from 16% to 32%. This increased number of AGNs is not sufficient to bring observations and predictions of HLIRG number densities in agreement, however. Even at cosmic noon around z ∼ 2, where the tension is lowest, it remains at a factor of just a few. The identification of radio AGNs in supposed SFGs highlights the value of high-resolution radio observations in studying dusty objects such as HLIRGs. Broad consistency is seen between Tb and the other AGN indicators, and the observed relation between SFR and Tb is seen as indicative of co-evolution between stellar mass build-up and black hole growth.

Radio-loud active galaxies have two accretion modes [radiatively inefficient (RI) and radiatively efficient (RE)], with distinct optical and infrared signatures, and two jet dynamical behaviours, which in arcsec- to arcmin-resolution radio surveys manifest primarily as centre- or edge-brightened structures [Fanaroff-Riley (FR) class I and II]. The nature of the relationship between accretion mode and radio morphology (FR class) has been the subject of long debate. We present a comprehensive investigation of this relationship for a sample of 286 well-resolved radio galaxies in the LOFAR Two-metre Sky Survey Deep Fields (LoTSS-Deep) first data release, for which robust morphological and accretion mode classifications have been made. We find that two-thirds of luminous FRII radio galaxies are RI, and identify no significant differences in the visual appearance or source dynamic range (peak/mean surface brightness) of the RI and RE FRIIs, demonstrating that both RI and RE systems can produce FRII structures. We also find a significant population of low-luminosity FRIIs (predominantly RI), supporting our earlier conclusion that FRII radio structures can be produced at all radio luminosities. We demonstrate that in the luminosity range where both morphologies are present, the probability of producing FRI or FRII radio morphology is directly linked to stellar mass, while across all morphologies and luminosities, RE accretion occurs in systems with high specific star formation rate, presumably because this traces fuel availability. In summary, the relationship between accretion mode and radio morphology is very indirect, with host-galaxy environment controlling these two key parameters in different ways., Comment: 22 pages, 17 figures, 7 tables. Accepted for publication in MNRAS. Update with minor changes to match published version

We investigate the radio-far infrared (FIR) correlation for a sample of $28$ bright high-redshift ($1 \lesssim z \lesssim 4$) star-forming galaxies selected in the FIR from the Herschel-ATLAS fields as candidates to be strongly gravitationally lensed. The radio information comes either from high sensitivity dedicated ATCA observations at $2.1$ GHz or from cross-matches with the FIRST survey at $1.4$ GHz. By taking advantage of source brightness possibly enhanced by lensing magnification, we identify a weak evolution with redshift out to $z\lesssim 4$ of the FIR-to-radio luminosity ratio $q_{\rm FIR}$. We also find that the $q_{\rm FIR}$ parameter as a function of the radio power $L_{1.4\,\rm GHz}$ displays a clear decreasing trend, similarly to what is observed for optically/radio selected lensed quasars found in literature, yet covering a complementary region in the $q_{\rm FIR}-L_{1.4\,\rm GHz}$ diagram. We interpret such a behavior in the framework of an in-situ galaxy formation scenario, as a result of the transition from an early dust-obscured star-forming phase (mainly pinpointed by our FIR selection) to a late radio-loud quasar phase (preferentially sampled by the optical/radio selection)., 12 pages, 6 figures. Minor changes and references updated to match the published version

The effect of Active Galactic Nuclei (AGN) on their host galaxies -- in particular their levels of star formation -- remains one of the key outstanding questions of galaxy evolution. Successful cosmological models of galaxy evolution require a fraction of energy released by an AGN to be redistributed into the interstellar medium to reproduce the observed stellar mass and luminosity function and to prevent the formation of over-massive galaxies. Observations have confirmed that the radio-AGN population is energetically capable of heating and redistributing gas at all phases, however, direct evidence of AGN enhancing or quenching star formation remains rare. With modern, deep radio surveys and large integral field spectroscopy (IFS) surveys, we can detect fainter synchrotron emission from AGN jets and accurately probe the star-forming properties of galaxies, respectively. In this paper, we combine data from the LOw Frequency ARray Two-meter Sky Survey with data from one of the largest optical IFS surveys, Mapping Nearby Galaxies at Apache Point Observatory to probe the star-forming properties of 307 local (z $, Accepted for publication in A&A. 24 pages, 14 figures

The far-infrared radio correlation (FIRC) is one of the strongest correlations in astronomy, yet a model that explains this comprehensively does not exist. The new LOFAR all Sky Survey (LoTSS) deep field, ELAIS-N1, allows exploration of this relation in previously unexplored regions of parameter space of radio frequency (150 MHz), luminosity (L150 24.7), redshift (z ∼ 1), and stellar mass M* 11.4. We present accurate deblended far-infrared (FIR) flux measurements with robust errors at 24, 100, 160, 250, 350, and 500 μm from Spitzer and the Herschel Space Observatory using XID+. We find that the FIRC has a strong mass dependence, the evolution of which takes the form qTIR(M*) = (2.00 ± 0.01)+(−0.22 ± 0.02)(log(M/M*)−10.05). This matches recent findings in regards to the star formation rate–radio luminosity relation at 150 MHz and results from radio observations in COSMOS at 1.4 GHz with the Jansky Very Large Array (JVLA). Our results provide tighter constraints on the low-redshift end of the FIRC and at lower frequency than the COSMOS observations. In addition, we find a mild evolution with redshift, with a best fit relation qTIR(z) = (1.94 ± 0.01)(1 + z)−0.04 ± 0.01. This evolution is shallower than that suggested by previous results at 150 MHz with the differences explained by the fact that previous studies did not account for the mass dependence. Finally, we present deblended FIR fluxes for 79 609 galaxies across the LoTSS deep fields: Boötes, ELAIS-N1, and Lockman Hole.

The \textit{Herschel} Astrophysical Terahertz Large Area Survey (H-ATLAS), that has covered about 642 sq. deg. in 5 bands from 100 to 500 $\mu\rm m$, allows a blind flux-limited selection of blazars at sub-mm wavelengths. However, blazars constitute a tiny fraction of H-ATLAS sources and therefore identifying them is not a trivial task. Using the data on known blazars detected by the H-ATLAS we have defined a locus for 500\,$\mu$m selected blazars and exploited it to select blazar candidates in the H-ATLAS fields. Candidates and known blazars in the H-ATLAS equatorial and South Galactic Pole fields were followed up with the Australia Telescope Compact Array (ATCA) or with the Karl G. Jansky Very Large Array (VLA), and matched with existing radio- and mm-catalogues to reconstruct the spectral behaviour over at least 6 orders of magnitude in frequency. We identified a selection approach that, combining the information in the sub-mm and radio domains, efficiently singles out genuine blazars. In this way, we identified a sample of 39 blazars brighter than $S_{500\mu\rm m} = 35\,$mJy in the H-ATLAS fields. Tests made cross-matching the H-ATLAS catalogues with large catalogues of blazar candidates indicate that the sample is complete. The derived counts are compared with model predictions finding good consistency with the C2Ex model and with estimates based on ALMA data., Comment: 16 pages, 7 figures, accepted by MNRAS

The feasibility of using time-varying magnetic field as a contactless cells permeabilization method was demonstrated by experimental results, but the underlying mechanism is still poorly understood. In this study a numerical analysis of the transmembrane potential (TMP) at cell membranes during permeabilization by time-varying magnetic fields was proposed, and a first quantification of mechanical stress induced by the magnetic and electric fields and hypothesized to play an important role in the permeabilization mechanism was carried out. TMP values induced by typical in-vitro experimental conditions were far below the values needed for membrane permeabilization, with a strong dependence on distance of the cell from the coil. The preliminary assessment of the mechanical pressure and potential deformation of cells showed that stress values evaluated in conditions in which TMP values were too low to cause membrane permeabilization were comparable to those known to influence the pore opening mechanisms.Clinical Relevance- Results represent a significant step towards a better comprehension of the mechanism underlying cell membrane permeabilization by time-varying magnetic fields.

In recent years the introduction of 5G networks is causing a drastically change of human exposure levels in the radio frequency range. The aim of this paper is on expanding the knowledge on this issue, assessing the exposure levels for a particular case of indoor 5G scenario, where the presence of an Access Point (AP) was simulated. Coupling the traditional deterministic computational method with an innovative stochastic approach, called Polynomial Chaos Kriging, allowed to evaluate the exposure variability of an user considering the 3D beamforming capability of the antenna. The exposure levels, expressed in terms of specific absorption rate (SAR) in specific tissues, showed low values compared to ICNIRP guidelines.

Dilution rate, dilution temperature and storage time have been recognized as vital steps in the processing of semen for storage before artificial insemination. The objective of this study was to determine optimal dilution and dilution temperature with an ostrich-specific semen extender for chilled storage. Four preselected ostrich (Struthio camelus var. domesticus) males, known for their ease of collection and specific semen quality parameters, were collected using the "dummy" female method. Dilution of 384 semen samples, at rates of 1:1, 1:2, 1:4 and 1:8 semen/diluent ratio with a diluent set at 5, 21 and 38 °C was performed and stored for 48 h at 5 °C. In vitro sperm function tests were conducted to evaluate treated semen during different storage intervals of 1, 5, 24 and 48 h. Motility and kinematic parameters were measured by the Sperm Class Analyzer®, the percentage live sperm measured by fluorescence SYBR14®/PI (LIVE/DEAD®), the percentage of sperm able to resist the hypo-osmotic swelling (HOS) stress test and sperm morphology determined by Nigrosin-Eosin staining. Progressive motility (PMOT), motility (MOT), sperm kinematics, LIVE and HOS were best (P 0.05) maintained at a higher dilution of 1:4-1:8. The beneficial effect (P 0.05) of a higher dilution temperature (21 °C) was prominent in terms of PMOT at a higher dilution. Storage of chilled semen at 5 °C requires dilution, at interpolated rates of 1:6-1:7, together with an extender temperature of 21 °C, to maintain optimal sperm function with minimal loss over a 48 h storage period.

Introduction: In Italy a new way of thinking about hospitals is emerging. It involves the articulation of care and resources according to the intensity and the complexity of care; patients acquire a central role and are no longer grouped by medical disciplines but by high, medium or low care complexity. Purpose of this study is to test a tool that detects care complexity in the areas of intervention, calculating and analyzing the care complexity of surgical patients in their first day after surgery. Methods: adoption of the Swot method to specify the Persiceto's Score tool, adapted to the Alexandrian context. The Persiceto tool consists of scores obtained from three elements: type of surgery, state of health/concurrent disease condition, autonomy level of the patient in various activities. Results: In an evaluation period of about 60 days the Persiceto tools completed on the first day after surgery were 80. The state of health and concurrent disease condition of the 80 patients was constituted by 43 with moderate systemic disease, 22 with severe systemic disease, 13 in good health and 2 in threatening health conditions. The level of care dependency that emerged from the IDA assessment of the 80 patients was 56 with low care dependency, 23 with average and 1 with high care dependency. Conclusions: This study has shown that a simple, effective and replicable tool can be useful during the reorganization of care intensity during post-surgery to obtain a precise classifications of care complexity.

We present the source associations, cross-identifications, and multi-wavelength properties of the faint radio source population detected in the deep tier of the LOFAR Two Metre Sky Survey (LoTSS): the LoTSS Deep Fields. The first LoTSS Deep Fields data release consists of deep radio imaging at 150~MHz of the ELAIS-N1, Lockman Hole, and Bo\"{o}tes fields, down to RMS sensitives of around 20, 22, and 32$~\mu$Jy\,beam$^{-1}$, respectively. These fields are some of the best studied extra-galactic fields in the northern sky, with existing deep, wide-area panchromatic photometry from X-ray to infrared wavelengths, covering a total of $\approx$~26~\mbox{deg$^{2}$}. We first generated improved multi-wavelength catalogues in ELAIS-N1 and Lockman Hole; combined with the existing catalogue for Bo\"{o}tes, we present forced, matched aperture photometry for over 7.2 million sources across the three fields. We identified multi-wavelength counterparts to the radio detected sources, using a combination of the Likelihood Ratio method and visual classification, which greatly enhances the scientific potential of radio surveys and allows for the characterisation of the photometric redshifts and the physical properties of the host galaxies. The final radio-optical cross-matched catalogue consists of 81\,951 radio-detected sources, with counterparts identified and multi-wavelength properties presented for 79\,820 ($>$97\%) sources. We also examine the properties of the host galaxies, and through stacking analysis find that the radio population with no identified counterpart is likely dominated by AGN at $z\sim3-4$. This dataset contains one of the largest samples of radio-selected star-forming galaxies and active galactic nuclei (AGN) at these depths, making it ideal for studying the history of star-formation, and the evolution of galaxies and AGN across cosmic time., Comment: 34 pages, 14 figures and 14 tables. Accepted for publication in A&A special issue. This paper is part of the 1st data release of the LoTSS Deep Fields. Electronic data catalogues will be made available on journal publication

Lyman alpha emitters (LAEs) in the Epoch of Reionization (EoR) offer valuable probes of early galaxy evolution and the process of reionization; however, the exact evolution of their abundance and the nature of their emission remain open questions. We combine samples of 229 and 349 LAE candidates at $z=5.7$ and $z=6.6,$ respectively, from the SILVERRUSH narrowband survey with deep Low Frequency Array (LOFAR) radio continuum observations in the ELAIS-N1 field to search for radio galaxies in the EoR and study the low-frequency radio properties of $z\gtrsim5.7$ LAE emitters. Our LOFAR observations reach an unprecedented noise level of $\sim20\,\mu$Jy beam$^{-1}$ at 150MHz, and we detect five candidate LAEs at $>5\sigma$ significance. Based on detailed spectral energy distribution modelling of independent multi-wavelength observations, we conclude that these sources are likely [OII] emitters at $z=1.47$, yielding no reliable $z\gtrsim5.7$ radio galaxy candidates. We examine the 111 $z=5.7$ and $z=6.6$ LAE candidates from our panchromatic photometry catalogue that are undetected by LOFAR, finding contamination rates of 81-92% for the $z=5.7$ and $z=6.6$ subset of the LAE candidate samples. This subset is biased towards brighter magnitudes and redder near-infrared colours. The contamination rates of the full sample will therefore likely be lower than the reported values. Contamination is lowered significantly through constraints on the near-infrared colours, highlighting the need for infrared observations to robustly identify bright LAEs in narrowband surveys. Finally, the stacking of radio continuum observations for the robust LAE samples yields 2$\sigma$ upper limits on radio luminosity of 8.2$\times$10$^{23}$ and 8.7$\times$10$^{23}$ W Hz$^{-1}$ at $z=5.7$ and $6.6$, respectively, corresponding to limits on their median star-formation rates of $, Comment: 17 pages, 11 figures, accepted for publication in A&A. The abstract is abridged. This paper is part of the 1st data release of the LoTSS Deep Fields

The Low Frequency Array (LOFAR) Two-metre Sky Survey (LoTSS) is a sensitive, high-resolution 120-168 MHz survey split across multiple tiers over the northern sky. The first LoTSS Deep Fields data release consists of deep radio continuum imaging at 150 MHz of the Bo��tes, European Large Area Infrared Space Observatory Survey-North 1 (ELAIS-N1), and Lockman Hole fields, down to rms sensitivities of $\sim$32, 20, and 22 $��$Jy beam$^{-1}$, respectively. In this paper we present consistent photometric redshift (photo-$z$) estimates for the optical source catalogues in all three fields - totalling over 7 million sources ($\sim5$ million after limiting to regions with the best photometric coverage). Our photo-$z$ estimation uses a hybrid methodology that combines template fitting and machine learning and is optimised to produce the best possible performance for the radio continuum selected sources and the wider optical source population. Comparing our results with spectroscopic redshift samples, we find a robust scatter ranging from 1.6 to 2% for galaxies and 6.4 to 7% for identified optical, infrared, or X-ray selected active galactic nuclei (AGN). Our estimated outlier fractions ($\left | z_{\text{phot}} - z_{\text{spec}} \right | / (1+z_{\text{spec}}) > 0.15$) for the corresponding subsets range from 1.5 to 1.8% and 18 to 22%, respectively. Replicating trends seen in analyses of previous wide-area radio surveys, we find no strong trend in photo-$z$ quality as a function of radio luminosity for a fixed redshift. We exploit the broad wavelength coverage available within each field to produce galaxy stellar mass estimates for all optical sources at $z < 1.5$. Stellar mass functions derived for each field are used to validate our mass estimates, with the resulting estimates in good agreement between each field and with published results from the literature., 23 pages, 14 figures. Accepted for publication in A&A. This paper is part of the 1st data release of the LoTSS Deep Fields - Electronic data catalogues will be made available on journal publication

International audience; The LOFAR Two-metre Sky Survey (LoTSS) will cover the full northern sky and, additionally, aims to observe the LoTSS deep fields to a noise level of ≲10 μJy beam−1 over several tens of square degrees in areas that have the most extensive ancillary data. This paper presents the ELAIS-N1 deep field, the deepest of the LoTSS deep fields to date. With an effective observing time of 163.7 h, it reaches a root mean square noise level of ≲20 μJy beam−1 in the central region (and below 30 μJy beam−1 over 10 square degrees). The resolution is ~6 arcsecs and 84 862 radio sources were detected in the full area (68 square degrees) with 74 127 sources in the highest quality area at less than 3 degrees from the pointing centre. The observation reaches a sky density of more than 5000 sources per square degree in the central region (~5 square degrees). We present the calibration procedure, which addresses the special configuration of some observations and the extended bandwidth covered (115–177 MHz; central frequency 146.2 MHz) compared to standard LoTSS. We also describe the methods used to calibrate the flux density scale using cross-matching with sources detected by other radio surveys in the literature. We find the flux density uncertainty related to the flux density scale to be ~6.5 per cent. By studying the variations of the flux density measurements between different epochs, we show that relative flux density calibration is reliable out to about a 3 degree radius, but that additional flux density uncertainty is present for all sources at about the 3 per cent level; this is likely to be associated with residual calibration errors, and is shown to be more significant in datasets with poorer ionosphere conditions. We also provide intra-band spectral indices, which can be useful to detect sources with unusual spectral properties. The final uncertainty in the flux densities is estimated to be ~10 per cent for ELAIS-N1.Key words: surveys / catalogs / radio continuum: general / radio continuum: galaxies★ Catalogs and images are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/648/A2★★ The data associated with this article are released at: https://lofar-surveys.org

The morphology of quiescent galaxies has been found to be correlated with the activity of their central super massive black hole. In this work, we use data from the first data release of the LOFAR Two$-$Metre Sky Survey (LoTSS DR1) and the Sloan Digital Sky Survey Data Release 7 (SDSS DR7) to select more than 15 000 quiescent galaxies at $z10^{21}\rm\,W\,Hz^{-1}$ at fixed stellar mass, velocity dispersion, or surface mass density does not depend on the galaxy projected axis ratio ($q$). However, the high-power ($L_{\rm 150\,MHz}>10^{23}\rm\,W\,Hz^{-1}$) RLAGNs are more likely to be found in massive, round galaxies, while the low- and intermediate-power ($L_{\rm 150\,MHz}\leq10^{23}\rm\,W\,Hz^{-1}$) RLAGNs have similar distributions of $q$ to non-RLAGN galaxies. We argue that our results support the picture that high-power RLAGNs are more easily triggered in galaxies with a merger-rich history, while low-power RLAGNs can be triggered in galaxies growing mainly via secular processes. Our work also supports the idea that the low-luminosity RLAGN may be sufficient for maintenance-mode feedback in low-mass quiescent galaxies with disc-like morphology, which is based on a simple extrapolation from the observed energy balance between cooling and RLAGN-induced cavities in massive clusters. We find no significant difference between the $q$ distributions of RLAGNs likely to be found in clusters and those likely not found in clusters after controlling the radio luminosity and stellar mass of the two samples, indicating that the environment does not significantly influence the morphology--RLAGN correlation., 14 pages, 8 figures, accepted for publication in A&A

This paper demonstrates the advantages of using ‘probabilistic fatigue simulation’ and ‘stochastic’ design over the traditional ‘deterministic’ design approach. It demonstrates how ‘Monte Carlo’ simulation with ‘Latin hypercube sampling’ are effective for obtaining simulated reliability tests based on standard FEA models. Particular attention is paid to recommendations for addressing the effects of fatigue endurance and static failure in the reliability analysis. It also describes how design ‘robustness’ is ensured by using a ‘factorial sampling’ technique in conjunction with a ‘response surface’ model. The requirements for a ‘Reduced Order Model’, obtainable from FEA, are discussed. Recommendations are made to address the effects of fatigue endurance, static failure and non-linearities in the fatigue life curves during Weibull analysis. A case study demonstrates how the methods are applied to an air-cooled intercooler. A comparison is made between measured reliability test results and simulations performed using both deterministic and stochastic approaches. The simulation offers excellent correlation with the experimental measurements. No further improvements in the model were deemed necessary and the model is considered a suitable platform for performing additional design simulations and for extrapolation of the reliability statistics.

SUMMARY: Ostrich females producing eggs in the absence of males was a major breakthrough for the development of an artificial insemination (AI) protocol. This study evaluated monthly egg production (EP) and average egg weight (EW) for 71 individually penned female ostriches from 2009 to 2020 and estimated the genetic parameters for these traits. EP was highly variable compared to EW (coefficients of variation: 124.9 vs. 10.27%, respectively). EP continued throughout the year with maxima from July to December and minima in February and May. The two-trait heritability (h2) for EP was low at 0.13, while EW had a higher h2 of 0.40. EP and EW were not genetically correlated. The genetic improvement of EP and EW for females used for AI is feasible. Further studies should target incubation and hatching traits after AI.

The identification of an emission line is unambiguous when multiple spectral features are clearly visible in the same spectrum. However, in many cases, only one line is detected, making it difficult to correctly determine the redshift. We developed a freely available unsupervised machine-learning algorithm based on unbiased topology (UMLAUT) that can be used in a very wide variety of contexts, including the identification of single emission lines. To this purpose, the algorithm combines different sources of information, such as the apparent magnitude, size and color of the emitting source, and the equivalent width and wavelength of the detected line. In each specific case, the algorithm automatically identifies the most relevant ones (i.e., those able to minimize the dispersion associated with the output parameter). The outputs can be easily integrated into different algorithms, allowing us to combine supervised and unsupervised techniques and increasing the overall accuracy. We tested our software on WISP (WFC3 IR Spectroscopic Parallel) survey data. WISP represents one of the closest existing analogs to the near-IR spectroscopic surveys that are going to be performed by the future Euclid and Roman missions. These missions will investigate the large-scale structure of the universe by surveying a large portion of the extragalactic sky in near-IR slitless spectroscopy, detecting a relevant fraction of single emission lines. In our tests, UMLAUT correctly identifies real lines in 83.2% of the cases. The accuracy is slightly higher (84.4%) when combining our unsupervised approach with a supervised approach we previously developed.

This paper evaluates the dose of exposure to radiofrequency electromagnetic fields (EMF) of people inside a car during vehicle-to-vehicle (V2V) communication operated at 5.9 GHz. The exposure dose is estimated with numerical simulations that make use of detailed and realistic 3D models of the geometry and material of the car and V2V antennas and of the organs and different tissues of an adult phantom at the driver position. The dose of EMF exposure was expressed in terms of the power absorbed by the tissues and organs of the driver and was quantified with the Specific Absorption Rate (SAR). The simulations revealed that SAR was higher in the body regions closer to the emitting antennas (the limbs) and very rapidly decreased with the distance from the antennas. Also, SAR values were observed only in the very superficial tissues, i.e., in the skin and were negligible elsewhere, such as in the muscles, bones and other more profound tissues. SAR values for both the whole-body- and local-body-exposure were well below the ICNIRP general public exposure limit in the 100 kHz-6 GHz frequency range and were equal to 1% and 7% of the limits of exposure for the whole-body and local body regions, respectively.

Aims. We aim to study the far-infrared radio correlation (FIRC) at 150 MHz in the local Universe (at a median redshift z~0:05) and improve the use of the rest-frame 150-MHz luminosity, L150, as a star-formation rate (SFR) tracer, which is unaffected by dust extinction. Methods. We cross-match the 60-um selected Revised IRAS Faint Source Survey Redshift (RIFSCz) catalogue and the 150-MHz selected LOFAR value-added source catalogue in the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) Spring Field. We estimate L150 for the cross-matched sources and compare it with the total infrared (IR) luminosity, LIR, and various SFR tracers. Results. We find a tight linear correlation between log L150 and log LIR for star-forming galaxies, with a slope of 1.37. The median qIR value (defined as the logarithm of the LIR to L150 ratio) and its rms scatter of our main sample are 2.14 and 0.34, respectively. We also find that log L150 correlates tightly with the logarithm of SFR derived from three different tracers, i.e., SFR_Halpha based on the Halpha line luminosity, SFR_60 based on the rest-frame 60-um luminosity and SFR_IR based on LIR, with a scatter of 0.3 dex. Our best-fit relations between L150 and these SFR tracers are, log L150 (Lsun) = 1.35(0.06) x log SFR_Halpha (Msun/yr) + 3.20(0.06), log L150 (Lsun) = 1.31(0.05) x log SFR_60 (Msun/yr) + 3.14(0.06), and log L150 (Lsun) = 1.37(0.05) x log SFR_IR (Msun/yr) + 3.09(0.05), which show excellent agreement with each other., 13 pages, 13 figures, accepted for publication in A&A

Concretes with 1% nano-Fe 3 O 4 addition aged for 300 days in chloride and sulfur dioxide chambers were analyzed by multiple technics and the performance results were evaluated by impedance spectroscopy and cyclic voltammetry. They exhibited a higher electrochemical stability because of the absence of passive film breakdown and an enhanced electrical resistance to charge transfer. The better properties were resulted from a more homogeneous microstructure produced by the byproducts of the reaction between the cement hydrates and the added nano-material. They were supposed be accumulated in pores and voids.

International audience; This study focused on the evaluation of the electric field induced in the brain grey matter of a 5 years child when exposed to uniform magnetic field at 50 Hz with uncertain orientation. An innovative approach that combines Principal Component Analysis (PCA) and Gaussian process regression (Kriging method) in order to build space-dependent surrogate models was applied and validated. Preliminary results showed the feasibility of the approach.

The development process of complex technical products of the last years shows an increasing amount of sensors, electronic control units, data logging and monitoring systems within consumer goods (e.g. automobiles, washing machines) and industrial goods (e.g. machine tools, manufacturing sys-tems). In many cases, the main goal of data logging is monitoring, controlling and optimisation of the product functionalities within the usage phase. A further aim is the fulfilment of the process capability of manufacturing processes. Therefore, the layout of the concept of operating data logging and monitoring systems—especially operating data (mainly type, volume, and format) as well as hardware (like sensors and storage)-is designed by the development engineer within the product concept development phase. This paper discusses challenges, requirements and approaches for future conceptual design of operating data logging concepts of technical products related to reliability engineering. Base of operations is the state of art. Based on that, the concept for operating data logging within a monitoring system is shown. The concept draft is subdivided in three parts which are divided as follows: part one deals with data analytics, part two contains data requirements, and part three focuses on hardware requirements. The presented research study was worked out on the international research platform “Computational Reliability Engineering in Product Development and Manufacturing (CRE) – 2017” and contains contributions of universities, institutes and original equipment manufacturers of industrial nations: Germany, United Kingdom, Japan, Turkey and France.

TATRASC2018Chiaramello. The Specific Absorption Rate (SAR) was estimated in all the possible positions of femtocell and child. Results showed that, for all the possible positions in the room, the exposure values were significantly below the International Commission of Non-Ionizing Radiation Protection (ICNIRP) guidelines for general public exposure. The variation of the distance between femtocell and child influenced greatly the exposure, resulting in Quartile Coefficient of Dispersion value equal to 67%.

This research used resources of the National Energy Research Scientific Computing Center, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. We also thank CSC — IT Center for Science (Finland) for computational resources. We acknowledge financial support by ASI Grant 2016-24-H.0 and Academy of Finland grant 295113. This work has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement number 687312. CJM is supported by an FCT Research Professorship, contract reference IF/00064/2012, funded by FCT/MCTES (Portugal) and POPH/FSE (EC). JGN acknowledges financial support from the Spanish MINECO for a ‘Ramon y Cajal’ fellowship (RYC-2013-13256) and the I+D 2015 project AYA2015-65887-P (MINECO/FEDER). GR acknowledges support from the National Research Foundation of Korea (NRF) through Grant No. 2017R1E1A1A01077508 funded by the Korean Ministry of Education, Science and Technology (MoEST), and from the faculty research fund of Sejong University in 2018. We thank Jean Kaplan for useful comments on the manuscript., Natoli, P., Ashdown, M., Banerji, R., Borrill, J., Buzzelli, A., De Gasperis, G., Delabrouille, J., Hivon, E., Molinari, D., Patanchon, G., Polastri, L., Tomasi, M., Bouchet, F.R., Henrot-Versillé, S., Hoang, D.T., Keskitalo, R., Kiiveri, K., Kisner, T., Lindholm, V., McCarthy, D., Piacentini, F., Perdereau, O., Polenta, G., Tristram, M., Achucarro, A., Ade, P., Allison, R., Baccigalupi, C., Ballardini, M., Banday, A.J., Bartlett, J., Bartolo, N., Basak, S., Baumann, D., Bersanelli, M., Bonaldi, A., Bonato, M., Boulanger, F., Brinckmann, T., Bucher, M., Burigana, C., Cai, Z.-Y., Calvo, M., Carvalho, C.-S., Castellano, M.G., Challinor, A., Chluba, J., Clesse, S., Colantoni, I., Coppolecchia, A., Crook, M., D'Alessandro, G., De Bernardis, P., Zotti, G.D., Valentino, E.D., Diego, J.-M., Errard, J., Feeney, S., Fernandez-Cobos, R., Finelli, F., Forastieri, F., Galli, S., Genova-Santos, R., Gerbino, M., González-Nuevo, J., Grandis, S., Greenslade, J., Gruppuso, A., Hagstotz, S., Hanany, S., Handley, W., Hernandez-Monteagudo, C., Hervías-Caimapo, C., Hills, M., Keihänen, E., Kitching, T., Kunz, M., Kurki-Suonio, H., Lamagna, L., Lasenby, A., Lattanzi, M., Lesgourgues, J., Lewis, A., Liguori, M., López-Caniego, M., Luzzi, G., Maffei, B., Mandolesi, N., Martinez-González, E., Martins, C.J.A.P., Masi, S., Matarrese, S., Melchiorri, A., Melin, J.-B., Migliaccio, M., Monfardini, A., Negrello, M., Notari, A., Pagano, L., Paiella, A., Paoletti, D., Piat, M., Pisano, G., Pollo, A., Poulin, V., Quartin, M., Remazeilles, M., Roman, M., Rossi, G., Rubino-Martin, J.-A., Salvati, L., Signorelli, G., Tartari, A., Tramonte, D., Trappe, N., Trombetti, T., Tucker, C., Valiviita, J., De Weijgaert, R.V., Tent, B.V., Vennin, V., Vielva, P., Vittorio, N., Wallis, C., Young, K., Zannoni, M.

We present new estimates of AGN accretion and star-formation luminosity in galaxies obtained for the local 12-$\mu$m sample of Seyfert galaxies (12MGS), by performing a detailed broad-band spectral energy distribution (SED) decomposition including the emission of stars, dust heated by star formation and a possible AGN dusty torus. Thanks to the availability of data from the X-rays to the sub-millimetre, we constrain and test the contribution of the stellar, AGN and star-formation components to the SEDs. The availability of Spitzer-IRS low resolution mid-infrared (mid-IR) spectra is crucial to constrain the dusty torus component at its peak wavelengths. The results of SED-fitting are also tested against the available information in other bands: the reconstructed AGN bolometric luminosity is compared to those derived from X-rays and from the high excitation IR lines tracing AGN activity like [Ne V] and [O IV]. The IR luminosity due to star-formation (SF) and the intrinsic AGN bolometric luminosity are shown to be strongly related to the IR line luminosity. Variations of these relations with different AGN fractions are investigated, showing that the relation dispersions are mainly due to different AGN relative contribution within the galaxy. Extrapolating these local relations between line and SF or AGN luminosities to higher redshifts, by means of recent Herschel galaxy evolution results, we then obtain mid- and far-IR line luminosity functions useful to estimate how many star-forming galaxies and AGN we expect to detect in the different lines at different redshifts and luminosities with future IR facilities (e.g., JWST, SPICA)., Comment: 27 pages, 13 figures, 7 tables. MNRAS in press

The exposure of an 8-years child moving in a room to a 4G LTE femtocell with uncertain position was assessed by stochastic dosimetry based on sparse low rank tensor approximation method (sparse LRA). The Specific Absorption Rate (SAR) was estimated in all the possible positions of femtocell and child. Results showed that, for all the possible positions in the room, the exposure values were significantly below the International Commission of Non-Ionizing Radiation Protection (ICNIRP) guidelines for general public exposure. The variation of the distance between femtocell and child influenced greatly the exposure, resulting in Quartile Coefficient of Dispersion value equal to 67%.

This study focused on the evaluation of the electric field induced in a 5 years child tissues exposed to uniform magnetic field at 50 Hz with uncertain orientation. An innovative approach combining Principal Component Analysis and Kriging method was proposed to build space-dependent surrogate model. Preliminary results showed the feasibility of the approach.

We thank the anonymous referee for useful comments, which helped to clarify the paper. Some of the results in this paper have been derived using the HEALPix package. Parts of the cosmological analysis was made using Cosmo MC, CLASS and MontePython. C.H.-M. acknowledges financial support of the Spanish Ministry of Economy and Competitiveness via I+D project AYA-2015-66211-C2-2-P. CJM is supported by an FCT Research Professorship, contract reference IF/00064/2012, funded by FCT/MCTES (Portugal) and POPH/FSE. J.G.N. acknowledges financial support from the Spanish MINECO for a ‘Ramon y Cajal’ fellowship (RYC-2013-13256) and the I+D 2015 project AYA2015-65887-P (MINECO/FEDER)., Melin, J.-B., Bonaldi, A., Remazeilles, M., Hagstotz, S., Diego, J.M., Hernández-Monteagudo, C., Génova-Santos, R.T., Luzzi, G., Martins, C.J.A.P., Grandis, S., Mohr, J.J., Bartlett, J.G., Delabrouille, J., Ferraro, S., Tramonte, D., Rubiño-Martín, J.A., Macìas-Pérez, J.F., Achúcarro, A., Ade, P., Allison, R., Ashdown, M., Ballardini, M., Banday, A.J., Banerji, R., Bartolo, N., Basak, S., Basu, K., Battye, R.A., Baumann, D., Bersanelli, M., Bonato, M., Borrill, J., Bouchet, F., Boulanger, F., Brinckmann, T., Bucher, M., Burigana, C., Buzzelli, A., Cai, Z.-Y., Calvo, M., Carvalho, C.S., Castellano, M.G., Challinor, A., Chluba, J., Clesse, S., Colafrancesco, S., Colantoni, I., Coppolecchia, A., Crook, M., D'Alessandro, G., De Bernardis, P., De Gasperis, G., Petris, M.D., Zotti, G.D., Valentino, E.D., Errard, J., Feeney, S.M., Fernández-Cobos, R., Finelli, F., Forastieri, F., Galli, S., Gerbino, M., González-Nuevo, J., Greenslade, J., Hanany, S., Handley, W., Hervias-Caimapo, C., Hills, M., Hivon, E., Kiiveri, K., Kisner, T., Kitching, T., Kunz, M., Kurki-Suonio, H., Lamagna, L., Lasenby, A., Lattanzi, M., Brun, A.M.C.L., Lesgourgues, J., Lewis, A., Liguori, M., Lindholm, V., Lopez-Caniego, M., Maffei, B., Martinez-Gonzalez, E., Masi, S., Mazzotta, P., McCarthy, D., Melchiorri, A., Molinari, D., Monfardini, A., Natoli, P., Negrello, M., Notari, A., Paiella, A., Paoletti, D., Patanchon, G., Piat, M., Pisano, G., Polastri, L., Polenta, G., Pollo, A., Poulin, V., Quartin, M., Roman, M., Salvati, L., Tartari, A., Tomasi, M., Trappe, N., Triqueneaux, S., Trombetti, T., Tucker, C., Väliviita, J., De Weygaert, R.V., Tent, B.V., Vennin, V., Vielva, P., Vittorio, N., Weller, J., Young, K., Zannoni, M.

Lensing of the CMB is now a well-developed probe of large-scale clustering over a broad range of redshifts. By exploiting the non-Gaussian imprints of lensing in the polarization of the CMB, the CORE mission can produce a clean map of the lensing deflections over nearly the full-sky. The number of high-S/N modes in this map will exceed current CMB lensing maps by a factor of 40, and the measurement will be sample-variance limited on all scales where linear theory is valid. Here, we summarise this mission product and discuss the science that it will enable. For example, the summed mass of neutrinos will be determined to an accuracy of 17 meV combining CORE lensing and CMB two-point information with contemporaneous BAO measurements, three times smaller than the minimum total mass allowed by neutrino oscillations. In the search for B-mode polarization from primordial gravitational waves with CORE, lens-induced B-modes will dominate over instrument noise, limiting constraints on the gravitational wave power spectrum amplitude. With lensing reconstructed by CORE, one can "delens" the observed polarization internally, reducing the lensing B-mode power by 60%. This improves to 70% by combining lensing and CIB measurements from CORE, reducing the error on the gravitational wave amplitude by 2.5 compared to no delensing (in the null hypothesis). Lensing measurements from CORE will allow calibration of the halo masses of the 40000 galaxy clusters that it will find, with constraints dominated by the clean polarization-based estimators. CORE can accurately remove Galactic emission from CMB maps with its 19 frequency channels. We present initial findings that show that residual Galactic foreground contamination will not be a significant source of bias for lensing power spectrum measurements with CORE. [abridged], 44 pages, 12 figures

Aim of this study is to quantify by means of computational electromagnetic techniques the electric field distribution (E) induced by a specific H-coil (named H4) used for deep Transcranial magnetic stimulation precisely designed for the addiction treatment.

A construção civil movimenta, anualmente, toneladas de cimento para as suas mais diversas aplicações, mas, a sua fabricação gera teores elevados de poluentes ambientais. Decorrente disto tem-se uma constante busca por novos métodos sustentáveis e alternativos de fabricação. Neste trabalho, a pesquisa foi direcionada em dois aspectos: a adição de fibras de coco (FC) e de sisal (FS) a um concreto referência, com a intenção de aumentar suas demandas nacionais e diminuir o impacto ambiental resultante da quantidade de resíduos descartados no ambiente após o consumo do fruto, com redução do consumo de cimento em cada dosagem, respectivamente; e, a fotocatálise de gases poluentes por argamassas à base do nanocomposto dióxido de titânio, fase anatásio. Para a avaliação do concreto com adições foram realizados ensaios de resistência à compressão axial, variação dimensional de barras de argamassa expostas em solução agressiva de sulfato e o acompanhamento da durabilidade de corpos de prova (CPs) envelhecidos em câmaras de intemperismo de névoa salina e de dióxido de enxofre pela técnica do potencial de corrosão. As argamassas com TiO2 foram avaliadas quanto ao seu potencial fotocatalítico para a redução na concentração de gases tipo NOx em câmara de UV-A, produzida para esta verificação. Os resultados indicaram um aumento em até 16% da resistência mecânica dos concretos com adições e uma eficiência das argamassas com teores de nano TiO2-fase anatásio a partir de 20% em massa, para promover a fotocatálise do NOx ao redor de 40%, em presença de radiação UV-A.

Samples of reinforced mortar specimens (Sps) were studied over 300 days of exposure in reference, sulfate, and chloride environments. Electrochemical impedance spectroscopy (EIS) was used to investigate external sulfate attack (ESA) in comparison with known chloride models. The study, based on the mortar behavior and its measured electrical properties, highlighted the mechanisms that occur under the pores during the aging. The sulfate samples presented a capacitive behavior at lower frequencies, and the mortar resistance shifted. It was confirmed that EIS is a qualified technique to identify the sulfate attack in concrete by non-destructive methods.

Photocatalytic materials can minimize atmospheric pollution by decomposing certain organic and inorganic pollutants using sunlight as an energy source. In this paper, the development of a methodology to measure the photocatalytic potential of mortar containing TiO2 nanoparticles is reported. The results indicate that up to 40% of NOx can be degraded by Portland cement mortar containing 30-50% of TiO2, which validates the method developed for evaluating the photocatalytic potential of materials.

The worldwide productions of banana were bigger than 95 million tons, which resemble to, approximately, 10.22 million tons of ashes. Additions of these residues or banana leaf ash (BLA) in mortars were investigated by ratios of 0–10% in replacement to weight of the Portland cement as pozzolanic materials. The products were characterized by chemical compositions, SEM, rheology and pozzolanic activity index. Hardened materials were characterized by tearing it in walls. The mechanical and chemical resistance performances of 10% and 20% BLA concrete samples were also evaluated by artificial ageing chambers. The BLA was considered a pozzolan material.

While continuum imaging data at far-infrared to sub-millimeter wavelengths have provided tight constraints on the population properties of dusty star forming galaxies up to high redshifts, future space missions like the Space Infra-Red Telescope for Cosmology and Astrophysics (SPICA) and ground based facilities like the Cerro Chajnantor Atacama Telescope (CCAT) will allow detailed investigations of their physical properties via their mid-/far-infrared line emission. We present updated predictions for the number counts and the redshift distributions of star forming galaxies spectroscopically detectable by these future missions. These predictions exploit a recent upgrade of evolutionary models, that include the effect of strong gravitational lensing, in the light of the most recent Herschel and South Pole Telescope data. Moreover the relations between line and continuum infrared luminosity are re-assessed, considering also differences among source populations, with the support of extensive simulations that take into account dust obscuration. The derived line luminosity functions are found to be highly sensitive to the spread of the line to continuum luminosity ratios. Estimates of the expected numbers of detections per spectral line by SPICA/SAFARI and by CCAT surveys for different integration times per field of view at fixed total observing time are presented. Comparing with the earlier estimates by Spinoglio et al. (2012) we find, in the case of SPICA/SAFARI, differences within a factor of two in most cases, but occasionally much larger. More substantial differences are found for CCAT., 20 pages, 14 figures, accepted for publication in MNRAS

The assessment of the relationship between radio continuum luminosity and star formation rate (SFR) is of crucial importance to make reliable predictions for the forthcoming ultra-deep radio surveys and to allow a full exploitation of their results to measure the cosmic star formation history. We have addressed this issue by matching recent accurate determinations of the SFR function up to high redshifts with literature estimates of the 1.4 GHz luminosity functions of star forming galaxies (SFGs). This was done considering two options, proposed in the literature, for the relationship between the synchrotron emission ($L_{\rm synch}$), that dominates at 1.4 GHz, and the SFR: a linear relation with a decline of the $L_{\rm synch}$/SFR ratio at low luminosities or a mildly non-linear relation at all luminosities. In both cases we get good agreement with the observed radio luminosity functions but, in the non-linear case, the deviation from linearity must be small. The luminosity function data are consistent with a moderate increase of the $L_{\rm synch}$/SFR ratio with increasing redshift, indicated by other data sets, although a constant ratio cannot be ruled out. A stronger indication of such increase is provided by recent deep 1.4 GHz counts, down to $\mu$Jy levels. This is in contradiction with models predicting a decrease of that ratio due to inverse Compton cooling of relativistic electrons at high redshifts. Synchrotron losses appear to dominate up to $z\simeq 5$. We have also updated the Massardi et al. (2010) evolutionary model for radio loud AGNs., Comment: 12 pages, 9 figures, accepted for publication in MNRAS

Observational investigations of the abundance of massive precursors of local galaxy clusters ("proto-clusters") allow us to test the growth of density perturbations, to constrain cosmological parameters that control it, to test the theory of non-linear collapse and how the galaxy formation takes place in dense environments. The Planck collaboration has recently published a catalogue of >~ 2000 cold extra-galactic sub-millimeter sources, i.e. with colours indicative of z >~ 2, almost all of which appear to be over-densities of star-forming galaxies. They are thus considered as proto-cluster candidates. Their number densities (or their flux densities) are far in excess of expectations from the standard scenario for the evolution of large-scale structure. Simulations based on a physically motivated galaxy evolution model show that essentially all cold peaks brighter than S_{545GHz} = 500 mJy found in Planck maps after having removed the Galactic dust emission can be interpreted as positive Poisson fluctuations of the number of high-z dusty proto-clusters within the same Planck beam, rather then being individual clumps of physically bound galaxies. This conclusion does not change if an empirical fit to the luminosity function of dusty galaxies is used instead of the physical model. The simulations accurately reproduce the statistic of the Planck detections and yield distributions of sizes and ellipticities in qualitative agreement with observations. The redshift distribution of the brightest proto-clusters contributing to the cold peaks has a broad maximum at 1.5, Comment: 10 pages, 8 figures, accepted for publication in MNRAS