The SAMI Galaxy Survey: the intrinsic shape of kinematically selected galaxies

Using the stellar kinematic maps and ancillary imaging data from the Sydney AAO Multi Integral field (SAMI) Galaxy Survey, the intrinsic shape of kinematically-selected samples of galaxies is inferred. We implement an efficient and optimised algorithm to fit the intrinsic shape of galaxies using an established method to simultaneously invert the distributions of apparent ellipticities and kinematic misalignments. The algorithm output compares favourably with previous studies of the intrinsic shape of galaxies based on imaging alone and our re-analysis of the ATLAS3D data. Our results indicate that most galaxies are oblate axisymmetric. We show empirically that the intrinsic shape of galaxies varies as a function of their rotational support as measured by the "spin" parameter proxy Lambda_Re. In particular, low spin systems have a higher occurrence of triaxiality, while high spin systems are more intrinsically flattened and axisymmetric. The intrinsic shape of galaxies is linked to their formation and merger histories. Galaxies with high spin values have intrinsic shapes consistent with dissipational minor mergers, while the intrinsic shape of low-spin systems is consistent with dissipationless multi-merger assembly histories. This range in assembly histories inferred from intrinsic shapes is broadly consistent with expectations from cosmological simulations.Comment: 15 pages, 11 figures, MNRAS in prin

Classic and modern in the therapy of hepatic hidatid cysts – experience of a general surgery center

Clinica II Chirurgie, Spitalul Județean de Urgențe ”Sf. Spiridon”, Iași UMF ”Gr.T. Popa” Iași, Al XI-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova „Iacomi-Răzeșu” 27-30 septembrie 2011INTRODUCERE. În ultimii 20 de ani, asistăm la o tendință de afirmare a terapiilor mai puțin invazive pentru pacienții cu chist hidatic hepatic (radiologie intervențională, endoscopie intervențională, puncții eco sau CT-ghidate, tehnici chirurgicale laparoscopice precum şi asocieri ale acestora). SCOP. Ne-am propus o comparație între rezultatele după abordul clasic şi cel minim-invaziv pentru tratamentul echinococozei hepatice. MATERIAL ŞI METODĂ. Au fost analizate retrospectiv 180 cazuri de chist hidatic hepatic operate în Clinica I Chirurgie Iaşi, România în perioada 2004-2010. Au fost selectate pentru analiză următoarele variabile: localizarea chistului, tipul acestuia (conform clasificării propuse de Informal Working Group on Echinococcosis), calea de abord, tehnica chirurgicală, durata evoluției postoperatorii, complicațiile survenite, recidivele şi asocierea chimioterapiei antiparazitare. Pentru analiza statistică s-au folosit testele neparametrice Mann-Whitney U şi Spearman cu pragul de semnificație p<0.05. REZULTATE. Leziunile s-au tratat prin puncție echoghidată (n=6;3.3%); pe cale laparoscopică (n= 48;26.6%) şi abord clasic (n=126;70.1%). Pe cale laparoscopică s-au efectuat: inactivare-aspirație-drenaj şi inactivare-aspirație-perichistectomie parțială. Pe cale clasică s-au practicat: inactivare-aspirație-drenaj, inactivare-aspirație-perichistectomie parțială, perichistectomie ideală, hepatectomie reglată, hepatectomie atipică. Abordul minim-invaziv se corelează semnificativ cu tipul I-II al chisturilor (p=0.016) şi cu localizarea acestora în segmentele II, III şi VI (p=0.001). Durata evoluției postoperatorii a fost semnificativ mai redusă după abordul laparoscopic (p=0.003) comparativ cu cea după intervențiile clasice „minimale” (inactivare-aspirație-drenaj şi inactivare-aspirație-perichistectomie parțială) practicate pentru leziunile tip I-III, dar diferența dintre numărul de zile de îngrijiri după abordul laproscopic vs. chirurgie radicală (perichistectomie ideală, hepatectomie) este nesemnificativă. Nu am întâlnit corelații semnificative între apariția recidivelor/complicațiilor şi tipul de abord. Chimioterapia antiparazitară, instituită în 118 de cazuri (65.5%), se corelează semnificativ cu o rată redusă a recidivelor survenite în 9 cazuri (5%). CONCLUZII. Boala hidatică beneficiază astăzi de o terapie multimodală în care chimioterapia, PAIR-ul, videochirurgia şi chirurgia clasică trebuie să se completeze cât mai fericit şi nu să se excludă. Chiar dacă „pierde din indicații”, chirurgia clasică rămâne „rezerva strategică” în terapia chistului hidatic.INTRODUCTION. In the last 20 years, we noticed an outstanding of less invasive therapy for the patients with hidatid disease (interventional radiology, interventional endoscopy, eco- or CT punctions, laparoscopy and association between these). AIM. We intend to compare the results after classic and laparoscopic approach as treatment for hepatic echinococcosis. METHODS. We analysed 180 cases operated in 1st Surgical Clinic, Iasi, Romania, between 2004-200. We recorded the fallowing parameters: location, type (classification approved by Informal Working Group on Echinococcosis), approaching type, surgical technique, postoperative evolution, complications, recurrences and chemotherapy. We used Mann-Whitney U and Spearman tests (p<0.05).RESULTS. The cases were solved by eco guidance punction (n=6; 3.3%); laparoscopic (n= 48; 26.6%) and classic approach (n=126; 70.1%). Minim invasive approach we did inactivation-suction-drainage and partial perichistectomy. Using open approach we did inactivation-suction-drainage, partial perichistectomy, total perichistectomy and hepatectomy. Laparoscopic treatment has significant correlation with type I-II (p=0.016) located in segments II, III and IV (p=0.001). Postoperative evolution is significant lower for laparoscopic methods (p=0.003) comparing with the „minimal” open techniques used for lesions type I-III. There is no significant differentiation between laparoscopic procedures and open radical surgery (total perichistectomy and hepatectomy). We did not register significant correlations about recurrences and complications. Chemotherapy used in 8 cases is correlated with a low rate of recurrence 9 cases (5%).CONCLUSIONS. Hidatid disease has the benefits of a multimodal therapy. Chemotherapy, PAIR, video surgery and open approach are completing themselves and not excluding each other. Even if classic methods are less frequent used, it remains as a „back up solution” in the therapy of hidatid cyst disease

The SAMI Galaxy Survey: the link between angular momentum and optical morphology

We investigate the relationship between stellar and gas specific angular momentum j, stellar mass M-* and optical morphology for a sample of 488 galaxies extracted from the Sydney-AAO Multi-object Integral field Galaxy Survey. We find that j, measured within one effective radius, monotonically increases with M-* and that, for M-* > 10(9.5) M-aS (TM), the scatter in this relation strongly correlates with optical morphology (i.e. visual classification and S,rsic index). These findings confirm that massive galaxies of all types lie on a plane relating mass, angular momentum and stellar-light distribution, and suggest that the large-scale morphology of a galaxy is regulated by its mass and dynamical state. We show that the significant scatter in the M-*-j relation is accounted for by the fact that, at fixed stellar mass, the contribution of ordered motions to the dynamical support of galaxies varies by at least a factor of 3. Indeed, the stellar spin parameter (quantified via lambda(R)) correlates strongly with S,rsic and concentration indices. This correlation is particularly strong once slow rotators are removed from the sample, showing that late-type galaxies and early-type fast rotators form a continuous class of objects in terms of their kinematic properties

Self-consistent bulge/disk/halo galaxy dynamical modeling using integral field kinematics

We introduce a method for modeling disk galaxies designed to take full advantage of data from integral field spectroscopy (IFS). The method fits equilibrium models to simultaneously reproduce the surface brightness, rotation, and velocity dispersion profiles of a galaxy. The models are fully self-consistent 6D distribution functions for a galaxy with a Sérsic profile stellar bulge, exponential disk, and parametric dark-matter halo, generated by an updated version of GalactICS. By creating realistic flux-weighted maps of the kinematic moments (flux, mean velocity, and dispersion), we simultaneously fit photometric and spectroscopic data using both maximum-likelihood and Bayesian (MCMC) techniques. We apply the method to a GAMA spiral galaxy (G79635) with kinematics from the SAMI Galaxy Survey and deep g- and r-band photometry from the VST-KiDS survey, comparing parameter constraints with those from traditional 2D bulge–disk decomposition. Our method returns broadly consistent results for shared parameters while constraining the mass-to-light ratios of stellar components and reproducing the H i-inferred circular velocity well beyond the limits of the SAMI data. Although the method is tailored for fitting integral field kinematic data, it can use other dynamical constraints like central fiber dispersions and H i circular velocities, and is well-suited for modeling galaxies with a combination of deep imaging and H i and/or optical spectra (resolved or otherwise). Our implementation (MagRite) is computationally efficient and can generate well-resolved models and kinematic maps in under a minute on modern processors.Publisher PDFPeer reviewe

The SAMI Galaxy Survey: revisiting galaxy classification through high-order stellar kinematics

Recent cosmological hydrodynamical simulations suggest that integral field spectroscopy can connect the high-order stellar kinematic moments h3 (~skewness) and h4 (~kurtosis) in galaxies to their cosmological assembly history. Here, we assess these results by measuring the stellar kinematics on a sample of 315 galaxies, without a morphological selection, using two-dimensional integral field data from the SAMI Galaxy Survey. Proxies for the spin parameter (${\lambda }_{{R}_{{\rm{e}}}}$) and ellipticity (${\epsilon }_{{\rm{e}}}$) are used to separate fast and slow rotators; there exists a good correspondence to regular and non-regular rotators, respectively, as also seen in earlier studies. We confirm that regular rotators show a strong h3 versus $V/\sigma$ anti-correlation, whereas quasi-regular and non-regular rotators show a more vertical relation in h3 and $V/\sigma$. Motivated by recent cosmological simulations, we develop an alternative approach to kinematically classify galaxies from their individual h3 versus $V/\sigma$ signatures. Within the SAMI Galaxy Survey, we identify five classes of high-order stellar kinematic signatures using Gaussian mixture models. Class 1 corresponds to slow rotators, whereas Classes 2–5 correspond to fast rotators. We find that galaxies with similar {\lambda }_{{R}_{{\rm{e}}}}\mbox{--}{\epsilon }_{{\rm{e}}} values can show distinctly different {h}_{3}\mbox{--}V/\sigma signatures. Class 5 objects are previously unidentified fast rotators that show a weak h3 versus $V/\sigma$ anti-correlation. From simulations, these objects are predicted to be disk-less galaxies formed by gas-poor mergers. From morphological examination, however, there is evidence for large stellar disks. Instead, Class 5 objects are more likely disturbed galaxies, have counter-rotating bulges, or bars in edge-on galaxies. Finally, we interpret the strong anti-correlation in h3 versus $V/\sigma$ as evidence for disks in most fast rotators, suggesting a dearth of gas-poor mergers among fast rotators

COVIDiSTRESS Global Survey dataset on psychological and behavioural consequences of the COVID-19 outbreak

This N = 173,426 social science dataset was collected through the collaborative COVIDiSTRESS Global Survey – an open science effort to improve understanding of the human experiences of the 2020 COVID-19 pandemic between 30th March and 30th May, 2020. The dataset allows a cross-cultural study of psychological and behavioural responses to the Coronavirus pandemic and associated government measures like cancellation of public functions and stay at home orders implemented in many countries. The dataset contains demographic background variables as well as measures of Asian Disease Problem, perceived stress (PSS-10), availability of social provisions (SPS-10), trust in various authorities, trust in governmental measures to contain the virus (OECD trust), personality traits (BFF-15), information behaviours, agreement with the level of government intervention, and compliance with preventive measures, along with a rich pool of exploratory variables and written experiences. A global consortium from 39 countries and regions worked together to build and translate a survey with variables of shared interests, and recruited participants in 47 languages and dialects. Raw plus cleaned data and dynamic visualizations are available

THE SAMI GALAXY SURVEY: REVISITING GALAXY CLASSIFICATION THROUGH HIGH-ORDER STELLAR KINEMATICS

Recent cosmological hydrodynamical simulations suggest that integral field spectroscopy can connect the high-order stellar kinematic moments h3 (~skewness) and h4 (~kurtosis) in galaxies to their cosmological assembly history. Here, we assess these results by measuring the stellar kinematics on a sample of 315 galaxies, without a morphological selection, using 2D integral field data from the SAMI Galaxy Survey. A proxy for the spin parameter ($\lambda_{R_e}$) and ellipticity ($\epsilon_e$) are used to separate fast and slow rotators; there exists a good correspondence to regular and non-regular rotators, respectively, as also seen in earlier studies. We confirm that regular rotators show a strong h3 versus $V/\sigma$ anti-correlation, whereas quasi-regular and non-regular rotators show a more vertical relation in h3 and $V/\sigma$. Motivated by recent cosmological simulations, we develop an alternative approach to kinematically classify galaxies from their individual h3 versus $V/\sigma$ signatures. We identify five classes of high-order stellar kinematic signatures using Gaussian mixture models. Class 1 corresponds to slow rotators, whereas Classes 2-5 correspond to fast rotators. We find that galaxies with similar $\lambda_{R_e}-\epsilon_e$ values can show distinctly different h3-$V/\sigma$ signatures. Class 5 objects are previously unidentified fast rotators that show a weak h3 versus $V/\sigma$ anti-correlation. These objects are predicted to be disk-less galaxies formed by gas-poor mergers. From morphological examination, however, there is evidence for large stellar disks. Instead, Class 5 objects are more likely disturbed galaxies, have counter-rotating bulges, or bars in edge-on galaxies. Finally, we interpret the strong anti-correlation in h3 versus $V/\sigma$ as evidence for disks in most fast rotators, suggesting a dearth of gas-poor mergers among fast rotators.Comment: Accepted for Publication in The Astrophysical Journal. 35 pages and 30 figures, abstract abridged for arXiv submission. The key figures of the paper are: 7, 11, 12 , and 1

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p&lt;0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p&lt;0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

The SAMI Galaxy Survey: Data Release One with emission-line physics value-added products

We present the first major release of data from the SAMI Galaxy Survey. This data release focuses on the emission-line physics of galaxies. Data Release One includes data for 772 galaxies, about 20 per cent of the full survey. Galaxies included have the redshift range 0.004 &lt; z &lt; 0.092, a large mass range (7.6 &lt; logM*/M⊙ &lt; 11.6), and star formation rates of ~10-4 to ~101M⊙ yr-1. For each galaxy, we include two spectral cubes and a set of spatially resolved 2D maps: single- and multi-component emission-line fits (with dust-extinction corrections for strong lines), local dust extinction, and star formation rate. Calibration of the fibre throughputs, fluxes, and differential atmospheric refraction has been improved over the Early Data Release. The data have average spatial resolution of 2.16 arcsec (full width at half-maximum) over the 15 arcsec diameter field of view and spectral (kinematic) resolution of R = 4263 (σ = 30 km s-1) around Ha. The relative flux calibration is better than 5 per cent, and absolute flux calibration has an rms of 10 per cent. The data are presented online through the Australian Astronomical Observatory's Data Central