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Galactic-scale outflows driven by active galactic nuclei (AGNs) represent a commonly invoked feedback mechanism within galaxy evolution models. However, the interactions among interstellar gas on galactic scales, the propagation of AGN outflows, and the fundamental parameters of AGNs during their evolutionary processes remain poorly understood. Notably, powerful nuclear outflows are typically associated with the early stages of AGN activity, which are characterized by high accretion rates and weak narrow emission lines. In our analysis of a sample of quasars hosting Mg ii narrow absorption lines (NALs) obtained from the Sloan Digital Sky Survey, we identify a previously unobserved phenomenon wherein galaxy-scale inflow transitions to outflow dominance, concurrent with a notable increase in the strength of the narrow [O III] line, achieving a confidence level of 6.7σ. This indicates that while nuclear outflows diminish, galaxy-wide outflows intensify as AGNs evolve. These findings suggest that early-stage outflows interact with the interstellar medium on a galactic scale, thereby facilitating a gradual transition to galaxy-wide outflows. This provides observational support for the hypothetical multi-stage propagation of AGN outflows that globally regulates galaxy evolution. [ABSTRACT FROM AUTHOR]

The nature and origin of supermassive black holes (SMBHs) remain an open matter of debate within the scientific community. While various theoretical scenarios have been proposed, each with specific observational signatures, the lack of sufficiently sensitive X-ray observations hinders the progress of observational tests. In this white paper, we present how AXIS will contribute to solving this issue. With an angular resolution of 1.5″ on-axis and minimal off-axis degradation, we designed a deep survey capable of reaching flux limits in the [0.5–2] keV range of approximately 2 × 10−18 erg s−1 cm−2 over an area of 0.13 deg2 in approximately 7 million seconds (7 Ms). Furthermore, we planned an intermediate depth survey covering approximately 2 deg2 and reaching flux limits of about 2 × 10−17 erg s−1 cm−2 in order to detect a significant number of SMBHs with X-ray luminosities (LX) of approximately 1042 erg s−1 up to z∼10. These observations will enable AXIS to detect SMBHs with masses smaller than 105 M⊙, assuming Eddington-limited accretion and a typical bolometric correction for Type II AGN. AXIS will provide valuable information on the seeding and population synthesis models of SMBHs, allowing for more accurate constraints on their initial mass function (IMF) and accretion history from z∼0–10. To accomplish this, AXIS will leverage the unique synergy of survey telescopes such as the JWST, Roman, Euclid, Vera Rubin Telescope, and the new generation of 30 m class telescopes. These instruments will provide optical identification and redshift measurements, while AXIS will discover the smoking gun of nuclear activity, particularly in the case of highly obscured AGN or peculiar UV spectra as predicted and recently observed by the JWST in the early Universe. [ABSTRACT FROM AUTHOR]

In the past years, the results obtained by the WISSH quasar project provided a novel general picture on the distinctive multi-band properties of hyper-luminous (Lbol > 1047 erg/s) quasars at high redshift (z ∼ 2-4), unveiling interesting relations among active galactic nuclei, winds and interstellar medium, in these powerful sources at cosmic noon. Since 2022, we are performing a systematic and statistically-significant VLA study of the radio properties of WISSH. We carried out high-resolution VLA observations aiming at: 1) identifying young radio source from the broad-band spectral shape of these objects; 2) sample an unexplored high redshift/high luminosity regime, tracking possible evolutionary effects on the radio-loud/radio-quiet dichotomy; 3) quantifying orientation effects on the observed winds/outflows properties. [ABSTRACT FROM AUTHOR]

The connection between X-ray weakness and powerful X-ray outflows is both expected in a scenario where outflows are connected with radiation-driven winds, and observed in several sources, both in the local Universe and at high redshift. Here I present the first results of a new study of this possible connection based on a search for SDSS quasars with weak X-ray emission in serendipitous XMM-Newton observations. The selected objects have a "normal" optical/UV blue continuum, but a flat and extraordinarily weak X-ray spectrum. The availability of rest-frame optical/UV spectra allows to check for the signature of outflows in the absorption lines and/or in the profiles of the emission lines. This method could reveal the presence of a population of so-far overlooked outflowing quasars and confirm the connection between winds and X-ray weakness in quasars. [ABSTRACT FROM AUTHOR]

Research articles in all branches of modern science are crowded with the abbreviated technical terms known as acronyms, a phenomenon that was essentially unknown before World War II. Apart from an introduction to the notion of acronyms and its short history, the paper discusses from a historical perspective the connections between acronyms and eponyms in science. Moreover, it charts how acronyms and abbreviations became so common in physics and astronomy that the excessive use of them came to be considered a symptom of a contagious disease. While many science acronyms are exotic and little used, and some downright bizarre, others have become household words that in some cases are not even recognized to be acronymic constructions. The paper briefly examines the naming histories of some of these successful acronyms in physics and astronomy, among them radar, sonar, maser, laser, and pulsar. [ABSTRACT FROM AUTHOR]

The QUASAR Phase 2b Induction Study evaluated the efficacy and safety of guselkumab, an interleukin-23p19 subunit antagonist, in patients with moderately to severely active ulcerative colitis (UC) with prior inadequate response and/or intolerance to corticosteroids, immunosuppressants, and/or advanced therapy. In this double-blind, placebo-controlled, dose-ranging, induction study, patients were randomized (1:1:1) to receive intravenous guselkumab 200 or 400 mg or placebo at weeks 0/4/8. The primary endpoint was clinical response (compared with baseline, modified Mayo score decrease ≥30% and ≥2 points, rectal bleeding subscore ≥1-point decrease or subscore of 0/1) at week 12. Guselkumab and placebo week-12 clinical nonresponders received subcutaneous or intravenous guselkumab 200 mg, respectively, at weeks 12/16/20 (uncontrolled study period). The primary analysis population included patients with baseline modified Mayo scores ≥5 and ≤9 (intravenous guselkumab 200 mg, n = 101; 400 mg, n = 107; placebo, n = 105). Week-12 clinical response percentage was greater with guselkumab 200 mg (61.4%) and 400 mg (60.7%) vs placebo (27.6%; both P <.001). Greater proportions of guselkumab-treated vs placebo-treated patients achieved all major secondary endpoints (clinical remission, symptomatic remission, endoscopic improvement, histo-endoscopic mucosal improvement, and endoscopic normalization) at week 12. Among guselkumab week-12 clinical nonresponders, 54.3% and 50.0% of patients in the 200- and 400-mg groups, respectively, achieved clinical response at week 24. Safety was similar among guselkumab and placebo groups. Guselkumab intravenous induction was effective vs placebo in patients with moderately to severely active UC. Guselkumab was safe, and efficacy and safety were similar between guselkumab dose groups. ClinicalTrials.gov number: NCT04033445. [Display omitted] Improvement at 12 weeks was greater with intravenous guselkumab vs placebo. Guselkumab-treated patients without a clinical response at 12 weeks benefited from additional guselkumab administered subcutaneously. Guselkumab was well tolerated. [ABSTRACT FROM AUTHOR]

The nature and origin of supermassive black holes (SMBHs) remain an open matter of debate within the scientific community. While various theoretical scenarios have been proposed, each with specific observational signatures, the lack of sufficiently sensitive X-ray observations hinders the progress of observational tests. In this white paper, we present how AXIS will contribute to solving this issue. With an angular resolution of 1.5″ on-axis and minimal off-axis degradation, we designed a deep survey capable of reaching flux limits in the [0.5–2] keV range of approximately 2 × 10−18 erg s−1 cm−2 over an area of 0.13 deg2 in approximately 7 million seconds (7 Ms). Furthermore, we planned an intermediate depth survey covering approximately 2 deg2 and reaching flux limits of about 2 × 10−17 erg s−1 cm−2 in order to detect a significant number of SMBHs with X-ray luminosities (LX) of approximately 1042 erg s−1 up to z∼10. These observations will enable AXIS to detect SMBHs with masses smaller than 105 M⊙, assuming Eddington-limited accretion and a typical bolometric correction for Type II AGN. AXIS will provide valuable information on the seeding and population synthesis models of SMBHs, allowing for more accurate constraints on their initial mass function (IMF) and accretion history from z∼0–10. To accomplish this, AXIS will leverage the unique synergy of survey telescopes such as the JWST, Roman, Euclid, Vera Rubin Telescope, and the new generation of 30 m class telescopes. These instruments will provide optical identification and redshift measurements, while AXIS will discover the smoking gun of nuclear activity, particularly in the case of highly obscured AGN or peculiar UV spectra as predicted and recently observed by the JWST in the early Universe.

Quasars are astronomical star-like objects having a large ultraviolet flux of radiation accompanied by generally broad emission lines and absorption lines in some cases found at large redshift. The used data is extracted from the Veron Cetti Catalogue of AGN and Quasar. The objective of this work is to partition the quasar based on their spectral properties using multivariate techniques and classify them with respect to the obtained clusters. Performing the K-means partitioning method, two robust clusters were obtained with cluster sizes 39,581 and 129,377. The percentage of misclassification observed based on the obtained clusters considering a multivariate classification technique and machine learning classification algorithm, i.e., linear discriminant analysis and XG-Boost, respectively. The linear discriminant analysis and XG-Boost evaluated a misclassification of around 0.84 and 0.15%, respectively. Additionally, a heuristic literature-based categorization subject to redshift yielded an accuracy of around 96%. This gives us cross-validating arguments about the astronomical data, that machine learning algorithms might perform on par with conventional multivariate techniques, if not better. [ABSTRACT FROM AUTHOR]

In this work, we investigate the possibility of observing quasars, particularly lensed quasars, by the Nancy Grace Roman Space Telescope (Roman). To this aim, based on the capabilities of the Roman Space Telescope and the results from the quasar luminosity function (QLF) in the infrared band of the Spitzer Space Telescope imaging survey, we calculated the number of quasars expected to be in its field of view. In order to estimate the number of lensed quasars, we develop a Monte Carlo simulation to estimate the probability that a quasar is lensed once or more times by foreground galaxies. Using the mass–luminosity distribution function of galaxies and the redshift distributions of galaxies and quasars, we find that 1 per 180 observed quasars will be lensed by foreground galaxies. Further on, adopting a singular isothermal sphere (SIS) model for lens galaxies, we calculate the time delay between lensed images for single and multiple lensing systems and present their distributions. We emphasize that detailed studies of these lensing systems will provide a powerful probe of the physical properties of quasars and may allow testing the mass distribution models of galaxies in addition to being extremely helpful for constraining the cosmological parameters. [ABSTRACT FROM AUTHOR]

In the blazar catalog BZCAT the objects are divided into 4 types: BZB, BZQ, BZG, and BZU. In this paper BZG objects are studied in order to determine their physical nature. Of the 274 BZG objects, 150 have optical spectra in the SDSS spectroscopic catalog, for which a detailed spectral classification has been carried out. A radio study showed that these objects mostly (69%) have a flat radio spectrum with a spectral index less than ±0.5. Quasars predominate among these kinds of radio spectra. However, with increasing distance, on the average the radio spectrum becomes steeper. [ABSTRACT FROM AUTHOR]

Nonparametric estimation for a probability density function that describes multivariate data has typically been addressed by kernel density estimation (KDE). A novel density estimator recently developed by Farmer and Jacobs offers an alternative high-throughput automated approach to univariate nonparametric density estimation based on maximum entropy and order statistics, improving accuracy over univariate KDE. This article presents an extension of the single variable case to multiple variables. The univariate estimator is used to recursively calculate a product array of one-dimensional conditional probabilities. In combination with interpolation methods, a complete joint probability density estimate is generated for multiple variables. Good accuracy and speed performance in synthetic data are demonstrated by a numerical study using known distributions over a range of sample sizes from 100 to 10 6 for two to six variables. Performance in terms of speed and accuracy is compared to KDE. The multivariate density estimate developed here tends to perform better as the number of samples and/or variables increases. As an example application, measurements are analyzed over five filters of photometric data from the Sloan Digital Sky Survey Data Release 17. The multivariate estimation is used to form the basis for a binary classifier that distinguishes quasars from galaxies and stars with up to 94% accuracy. [ABSTRACT FROM AUTHOR]

H2O megamaser emission from sub-parsec circumnuclear disks at the center of active galaxies allows a single-step, direct distance measurements to galaxies in the Hubble flow without any external calibration. Based on accurate distance determinations of six maser galaxies within 150 Mpc, the Megamaser Cosmology Project (MCP) team recently obtained H0 = 73.9± 3.0 km/s/Mpc ('∼ 4% accuracy), independent of distance ladders and the cosmic microwave background. To further applying the megamaser technique to attain a 1% Ho measurement, detecting more high-quality disk maser systems is crucial. In this conference proceeding, we update the status of the MCP and discuss strategies of detecting additional high-quality disk maser galaxies within z ∼ 0.1. In addition, we show the prospects of reaching a 1% Ho measurement with the supreme sensitivity of the ngVLA. Finally, we demonstrate that applying the maser technique to distance measurements of high-z galaxies with future submm VLBI systems is promising and this will allow for investigation of the new tension between the ΛCDM model and the high-z Hubble diagram. [ABSTRACT FROM AUTHOR]

Multiply imaged time-variable sources can be used to measure absolute distances as a function of redshifts and thus determine cosmological parameters, chiefly the Hubble Constant H 0 . In the two decades up to 2020, through a number of observational and conceptual breakthroughs, this so-called time-delay cosmography has reached a precision sufficient to be an important independent voice in the current "Hubble tension" debate between early- and late-universe determinations of H 0 . The 2020s promise to deliver major advances in time-delay cosmography, owing to the large number of lenses to be discovered by new and upcoming surveys and the vastly improved capabilities for follow-up and analysis. In this review, after a brief summary of the foundations of the method and recent advances, we outline the opportunities for the decade and the challenges that will need to be overcome in order to meet the goal of the determination of H 0 from time-delay cosmography with 1% precision and accuracy. [ABSTRACT FROM AUTHOR]

In this work, we investigate the possibility of observing quasars, particularly lensed quasars, by the Nancy Grace Roman Space Telescope (Roman). To this aim, based on the capabilities of the Roman Space Telescope and the results from the quasar luminosity function (QLF) in the infrared band of the Spitzer Space Telescope imaging survey, we calculated the number of quasars expected to be in its field of view. In order to estimate the number of lensed quasars, we develop a Monte Carlo simulation to estimate the probability that a quasar is lensed once or more times by foreground galaxies. Using the mass–luminosity distribution function of galaxies and the redshift distributions of galaxies and quasars, we find that 1 per 180 observed quasars will be lensed by foreground galaxies. Further on, adopting a singular isothermal sphere (SIS) model for lens galaxies, we calculate the time delay between lensed images for single and multiple lensing systems and present their distributions. We emphasize that detailed studies of these lensing systems will provide a powerful probe of the physical properties of quasars and may allow testing the mass distribution models of galaxies in addition to being extremely helpful for constraining the cosmological parameters.

Quasars are astronomical star-like objects having a large ultraviolet flux of radiation accompanied by generally broad emission lines and absorption lines in some cases found at large redshift. The used data is extracted from the Veron Cetti Catalogue of AGN and Quasar. The objective of this work is to partition the quasar based on their spectral properties using multivariate techniques and classify them with respect to the obtained clusters. Performing the K-means partitioning method, two robust clusters were obtained with cluster sizes 39,581 and 129,377. The percentage of misclassification observed based on the obtained clusters considering a multivariate classification technique and machine learning classification algorithm, i.e., linear discriminant analysis and XG-Boost, respectively. The linear discriminant analysis and XG-Boost evaluated a misclassification of around 0.84 and 0.15%, respectively. Additionally, a heuristic literature-based categorization subject to redshift yielded an accuracy of around 96 %. This gives us cross-validating arguments about the astronomical data, that machine learning algorithms might perform on par with conventional multivariate techniques, if not better.

Purpose: Studying the accretion disc structure in the Q2237+0305 gravitationally lensed quasar in optical wavelengths; estimation of parameters of the matter accretion regime onto a central black hole. Design/methodology/approach: Measuring the time delays between the quasar brightness variations in two spectral ranges allows to obtain direct estimates of distances between the quasar’s zones, which radiate in the selected wavelengths (the reverberation mapping method). Findings: New estimates of the time delays between the Q2237+0305 light curves in the R and V spectral bands have been obtained from the observations of 2004, as well as more accurate estimates for the light curves of the 2005 season reported earlier. The time delay value averaged over the two years is ΔtR-V ≈ 6.7 ± 2.4 days in the observer’s coordinate system, or Δt̃R-V ≈ 2.49 ± 0.9 days in the rest frame. With this delay, a distance between the accretion disk annular zones responsible for the radiation in V and R is RR-RV = Δt̃R-V · c ≈ 6.46·1015 sm. This indicates an accretion disk size far exceeding that one predicted by the standard thin accretion disc model by Shakura and Sunyaev. In this work, a suggestion is checked that thus large disk size can be a consequence of a super-critical (super-Eddington) accretion regime considered in the classical work by Shakura and Sunyaev, where the supercritical accretion regime has been shown to results in formation of an extended optically thick scattering envelope on the disk periphery. Conclusions: Analytical expressions for the radius and temperature of such an envelope derived by Shakura and Sunyaev have been used in this work to calculate the RR and RV envelope dimensions in the R and V spectral bands expected from the super-critical accretion regime scenario in the Q2237+0305 quasar. The calculations have been made for three values of the black hole mass covering the whole range of the existing estimates for Q2237+0305, from MВH = 2·108 Mʘ to MВH = 20·108 Mʘ. The accretion rate was assumed to be ṁ = 17. The calculated envelope radii in spectral bands R and V are well consistent with the inter-band time delay value of 2.49 days obtained in the present work from the data of observations. Thus, it can be argued that the black hole in the Q2237+0305 quasar is accreting the matter in a moderately super-critical regime, which results in creating an extended optically thick scattering envelope, and this is just in this envelope that the reverberation responses examined in this work arise. Parameter α for the black hole- (efficiency of the angular momentum transport) is varying within 0.005 0.006 minimal mass, and from 0.029 to 0.033 for the maximal one, while parameter A (ratio of the energy losses in Compton scattering to those in free-free transitions) is within 50 to 100.

Studies of extended extragalactic radio sources have an important feature and significance for forming an opinion about the distribution of matter in the Universe. The galaxy NGC 315 is an extended radio source within which there are many compact radio sources that form its intensity. Studies of this galaxy and its surroundings assume that although there are many sources in the NGC 315 immediate vicinity, in its wider 6° circumferences, there is a deficiency of extragalactic sources, and this deficiency is more clearly expressed at distances between 0.8 and 2.2 redshifts. Considering the distribution of extragalactic sources in this region, we can state that this does not give grounds to consider the distribution in the Universe to be uniform, which indicates the heterogeneity of the Universe, although some doubts remain here. To solve this problem, it is necessary to carry out non-standard, more sensitive, and targeted multi-frequency observations, which will allow obtaining such results that will make the identification of the obtained multi-frequency data more reliable. One of the possible promising directions for solving this problem is, in particular, the possibility of using microchannel plates (MCPs) as radiation detectors, the technology of which has begun to develop rapidly in recent years. [ABSTRACT FROM AUTHOR]

Purpose: Studying the spatial structure of the quasar in the Q2237+0305 gravitational lens system in optical spectral range; estimating the central black hole mass. Design/methodology/approach: The method of reverberation mapping has been used that implies measuring of the time delays between the quasar intrinsic brightness variations in different spectral ranges. We used the macroimage light curves of the Q2237+0305 system in spectral bands V (λeff = 547.7 nm) and R (λeff = 634.9 nm) of Johnson–Cousins photometric system. The reverberation mapping method allows to obtain direct estimates of distances between the quasar regions responsible for radiation in the selected spectral bands. Findings: The time delay between the V and R light curves is estimated to be 5.58±1.69 days, which is more than an order of magnitude larger than that predicted by a standard thin accretion disk model by Shakura–Sunyaev. As an explanation, a suggestion is made that the standard accretion disk model is not entirely adequate when describing an actual quasar structure. Conclusions: Such a large time delay means that reverberation responses arise in extended structures located outside the accretion disk. A suggestion that some extended structure capable to efficiently radiate in optical band may exist around the accretion disks has been reported in a number of works dedicated to the microlensing studies and analysis of flux ratio anomalies in gravitationally lensed quasars. Abolmasov and Shakura have shown analytically that a super-Eddington accretion regime may take place for some quasars, which leads to formation of an envelope. The envelope scatters radiation from the disk, thus making the apparent disk size larger. The further development in studying the spatial structure of the Q2237+0305 quasar with the use of reverberation mapping implies involving the data in spectral band I. This will provide two additional spectral bases thus allowing investigation of a wavelength dependence of the corresponding structure dimensions.

A full-length three-dimensional structure of the tetrameric potassium ion channel (hERG Kv11.1) including the N- and C-terminal domains was built, with a diameter of 6 Å and 12 Å between the K + selectivity filter and the pore cavity residue Tyr652 of opposite subunits. Further docking studies with a set of 233 structurally known blockers have shown that compounds bind near the inner vestibule of the pore channel, as well as the helix-IV region of the voltage sensor domain (VSD) in the alpha subunit. The residues of hERG, Gly626, Phe627, Gly628, Tyr652 and Phe656 of the pore channel and Arg488 of VSD plays an important role in ligand binding and hERG blockage. The conducted QuaSAR model is statistically significant, with R2 of 0.72 in predicting the hERG blocking activity. Furthermore, QuaSAR descriptors employing computer-assisted multiple regression procedure reveal that increase in hydrophobicity with higher number of aromatic rings are favorable for the binding affinity of hERG blockers. Additionally, the pIC50 values of 25 commercial compounds screened using structure-based pharmacophore model also show binding to the selectivity filter and pore cavity of hERG potassium channel like the known hERG blockers with a wide range of inhibition from weak to strong blockage predicting to have proarrhythmic potential.

Software untuk mengelola data transaksi menjadi laporan keuangan sangat banyak dipakai di berbagai sektor bisnis. Software yang cepat, akurat, reliabilitas tinggi serta mudah diimplementasikan menjadi faktor pemilihan software. Oleh karena itu, dikembangkan software pengelola transaksi dengan menggunakan PWA (Progressive Web Apps). Alasan memanfaatkan PWA karena dapat memenuhi kebutuhan software yang dibutuhkan oleh pengguna. Secara garis besar, kelebihan PWA ini terletak pada bagian notifikasi, dapat diakses secara offline, memiliki performa yang bagus, sistem keamanan yang bagus (karena harus menggunakan HTTPS), dan dapat diterapkan pada web. Penerapan PWA ini juga sama seperti memakai aplikasi di smartphone. Uji coba dalam pengembangan ini dilakukan dengan dua metode, yaitu Performance Testing dan Functionality Testing. Hasil uji coba menyatakan bahwa web akuntansi dengan PWA mempunyai kecepatan yang hampir sama dengan native tetapi User Experience PWA lebih baik dibandingkan aplikasi native. Hasil dari Functionality Testing menunjukan Web App dapat berjalan dengan baik sesuai fungsi setiap fitur.

It is an unsolved mystery that the rotation velocity of a galactic disc is same at any radial distances. The presence of dark matter is expected, but not observed. Here we propose a novel scheme for the evolution of the initial cosmic energy to current galaxies. According to the energy circulation theory, which we previously reported, the fundamental force works based on momentums. Antiparallel movements of energy pieces form a circulation. Due to the space expansion, the initial energy circulations separate and decompose to smaller level circulations; to galactic seeds, stellar seeds, and smallest energy circulations. The internal circulating velocity of a galactic seed is inherited to the circulating speed of stellar seeds in a ring. The intra-circulation interaction by the fundamental force keeps the stellar seeds to circulate at the initial speed, which does not alter by the space expansion. The new scheme meets the galaxy rotation curve without requiring dark matter.

The effort for understanding the matter and energy content of the Universe and its evolution relies on different probes, such as cosmic background radiation, cluster lensing, supernovae. Yet, we are still far from grasping what dark matter is made of, and what the physical origin of dark energy is. Our group has developed a technique that makes use of the observed non-linear relation between the ultraviolet and the X-ray luminosity in quasars to provide an independent measurement of their distances, thus turning quasars into standardizable candles. This technique, at present, it is mostly based upon quasar samples with data from public catalogs both in the X-rays and in the optical/ultraviolet and extends the Hubble diagram of supernovae to a redshift range still poorly explored (z > 2). From the X-ray perspective, we are now on the eve of a major change, as the upcoming mission eROSITA is going to provide us with up to ~3 millions of active galactic nuclei across the entire sky. Here we present predictions for constraining cosmological parameters, such as the amount of dark matter (Ωm), dark energy (ΩΛ) and the evolution of the equation of state of dark energy (w) through the Hubble diagram of quasars, based on the 4-years eROSITA all-sky survey. Our simulations show that the eROSITA quasars, complemented by redshift and broad-band photometric information, will supply the largest quasar sample at z < 2, but with very few objects available for cosmology at higher redshifts that survives the cut for the Malmquist bias, as eROSITA will sample the brighter end of the X-ray luminosity function. The power of the quasar Hubble diagram for precision cosmology lies in the high-redshift regime, where quasars can be observed up to redshift ~7.5, essential to discriminate amongst different model extrapolations. Therefore, to be competitive for cosmology, the eROSITA quasar Hubble diagram must be complemented with the already available quasar samples and dedicated (deep) large programmes at redshift z > 3.

Este trabajo describe la aplicación de un modelo de calidad de agua para la simulación de metales pesados en sistemas fluviales. La estrategia propuesta incluye un enfoque de modelación 1D con la extensión del modelo QUASAR-ADZ para la representación del comportamiento de los metales pesados, buscando fortalecer su capacidad predictiva a partir de la integración de variables que juegan un papel importante en la adsorción y desorción de estos compuestos por las partículas en solución. La metodología se implementó en un tramo del río Negro (oriente de Antioquia, Colombia), utilizando cromo, cobre y níquel como metales pesados, debido a que son estos los metales pesados representativos de las corrientes en el área de estudio. En los resultados se muestra la capacidad de predicción de la metodología del comportamiento de sustancias de interés ambiental con cierto grado de incertidumbre, lo que la constituye en una herramienta de gestión importante.

Featuring the same musicians since 1994, for 25 years the Quasar saxophone quartet has developed an artistic approach focused on creation and innovation. Through close collaboration with composers at various stages of the creative process, the quartet actively participates in the enrichment of the repertoire for their ensemble. Through workshop structures such as the Électro Series, Quasar is not only at the cutting edge of new musical practices, they also foster the exposure of Quebec and Canadian music locally and internationally. After briefly contextualizing the musical milieu in Montreal that saw the ensemble's formation in the 1990s, this article traces the milestones that led Quasar to their unique and distinctive art. [ABSTRACT FROM AUTHOR]

Aims: Beta2‐microglobulin (B2M) forms part of the HLA class I complex and plays a role in metastatic biology. B2M mutations occur frequently in mismatch repair‐deficient colorectal cancer (dMMR CRC), with limited data suggesting they may protect against recurrence. Our experimental study tested this hypothesis by investigating B2M mutation status and B2M protein expression and recurrence in patients in the stage II QUASAR clinical trial. Methods and results: Sanger sequencing was performed for the three coding exons of B2M on 121 dMMR and a subsample of 108 pMMR tumours; 52 with recurrence and 56 without. B2M protein expression was assessed by immunohistochemistry. Mutation status and protein expression were correlated with recurrence and compared to proficient mismatch repair (pMMR) CRCs. Deleterious B2M mutations were detected in 39 of 121 (32%) dMMR tumours. Five contained missense B2M‐variants of unknown significance, so were excluded from further analyses. With median follow‐up of 7.4 years, none of the 39 B2M‐mutant tumours recurred, compared with 14 of 77 (18%) B2M‐wild‐type tumours (P = 0.005); six at local and eight at distant sites. Sensitivity and specificity of IHC in detecting B2M mutations was 87 and 71%, respectively. Significantly (P < 0.0001) fewer (three of 104, 2.9%) of the 108 pMMR CRCs demonstrated deleterious B2M mutations. One pMMR tumour, containing a frameshift mutation, later recurred. Conclusion: B2M mutations were detected in nearly one‐third of dMMR cancers, none of which recurred. B2M mutation status has potential clinical utility as a prognostic biomarker in stage II dMMR CRC. The mechanism of protection against recurrence and whether this protection extends to stage III disease remains unclear. [ABSTRACT FROM AUTHOR]

The analysis of blazars' parameters from BZCAT leads to a conclusion that they do not have the same properties. The preliminary criterion to include an object in the catalog was the strong radio emission; however, two type of radio sources were selected: BL Lacertae (BLL) objects and Flat Spectrum Radio Quasars (FSRQ). As a number of properties are typical of blazars (strong radio emission, optical variability, continuum optical spectra, polarization, high luminosity, etc.), using the optical data, we investigate them to clarify which property plays the most significant role in their classification as blazars. We found that 60% of blazars have optical variability. We use a technique developed based on POSS1 and POSS2 photometry and group the variability into extreme, strong, medium, and low classes. In the optical range, 51 blazars have powerful variability (extreme variables), and 126 are high variables. In addition, 63% of blazars have detected radiation in X‐ray and 28% have detected radiation in gamma rays. We give the average statistical characteristics of blazars based on our analysis and calculations. [ABSTRACT FROM AUTHOR]

Here we investigate the connection of broad emission line shapes and continuum light curve variability time scales of type-1 Active Galactic Nuclei (AGN). We developed a new model to describe optical broad emission lines as an accretion disk model of a line profile with additional ring emission. We connect ring radii with orbital time scales derived from optical light curves, and using Kepler's third law, we calculate mass of central supermassive black hole (SMBH). The obtained results for central black hole masses are in a good agreement with other methods. This indicates that the variability time scales of AGN may not be stochastic, but rather connected to the orbital time scales which depend on the central SMBH mass.

We propose a modified version of the observed non-linear relation between the X-ray (2 keV) and the ultraviolet (2,500 Å) emission in quasars (i.e., LX∝LUVγ) which involves the full width at half-maximum, FWHM, of the broad emission line, i.e., LX∝LUVγ^ FWHMβ^. By analyzing a sample of 550 optically selected non-jetted quasars in the redshift range of 0.36–2.23 from the Sloan Digital Sky Survey cross matched with the XMM-Newton catalog 3XMM-DR6, we found that the additional dependence of the observed LX − LUV correlation on the FWHM of the Mgii broad emission line is statistically significant. Our statistical analysis leads to a much tighter relation with respect to the one neglecting FWHM, and it does not evolve with redshift. We interpret this new relation within an accretion disc corona scenario where reconnection and magnetic loops above the accretion disc can account for the production of the primary X-ray radiation. For a broad line region size depending on the disc luminosity as Rblr∝Ldisc0.5, we find that LX∝LUV4/7 FWHM4/7, which is in very good agreement with the observed correlation.

Prior to the Fermi-LAT era, only two classes of Active Galactic Nuclei (AGN) were thought to harbor relativistic jets that radiate up to gamma-ray energies: blazars and radio galaxies. The detection of variable gamma-ray emission from Narrow Line Seyfert 1 (NLSy1) galaxies has put them on the spotlight as a new class of gamma-ray emitting AGN. In this respect, gamma-ray emitting NLSy1s seem to be situated between blazars (dominated by non-thermal emission) and Seyferts (accretion disc dominated). In this work, we model the Spectral Energy Distribution (SED) of two gamma-loud NLSy1s, 1H 0323+342 and B2 0954+25A, during quiescent and flaring episodes via a multi-component radiative model that features a relativistic jet and external photon fields from the torus, disc, corona and Broad Line Region (BLR). We find that the interpretation of the high-energy emission of jetted NLSy1s requires taking into account Inverse Compton emission from particles in the relativistic jet that interact with external photon fields. Minimal changes are applied to the model parameters to transition from average to flaring states. In this scenario, the observed variability is explained mainly by means of changes in the jet density and Doppler factor.

The properties of circum-galactic gas in the halo of quasar host galaxies are investigated analyzing Mg II 2800 and C IV 1540 absorption-line systems along the line of sight close to quasars. We used optical spectroscopy of closely aligned pairs of quasars (projected distance ≤ 200 kpc, but at very different redshift) obtained at the VLT and Gran Telescopio Canarias to investigate the distribution of the absorbing gas for a sample of quasars at z ~1. Absorption systems of EW ≥0.3 associated with the foreground quasars are revealed up to 200 kpc from the centre of the host galaxy, showing that the structure of the absorbing gas is patchy with a covering fraction quickly decreasing beyond 100 kpc. In this contribution we use optical and near-IR images obtained at VLT to investigate the relations between the properties of the circum-galactic medium of the host galaxies and of the large scale galaxy environments of the foreground quasars.