Star-forming dwarf galaxies in the Virgo cluster: the link between molecular gas, atomic gas, and dust

We present $^{12}$CO(1-0) and $^{12}$CO(2-1) observations of a sample of 20 star-forming dwarfs selected from the Herschel Virgo Cluster Survey, with oxygen abundances ranging from 12 + log(O/H) ~ 8.1 to 8.8. CO emission is observed in ten galaxies and marginally detected in another one. CO fluxes correlate with the FIR 250 $\mu$m emission, and the dwarfs follow the same linear relation that holds for more massive spiral galaxies extended to a wider dynamical range. We compare different methods to estimate H2 molecular masses, namely a metallicity-dependent CO-to-H2 conversion factor and one dependent on H-band luminosity. The molecular-to-stellar mass ratio remains nearly constant at stellar masses <~ 10$^9$ M$_{\odot}$, contrary to the atomic hydrogen fraction, M$_{HI}$/M$_*$, which increases inversely with M$_*$. The flattening of the M$_{H_2}$/M$_*$ ratio at low stellar masses does not seem to be related to the effects of the cluster environment because it occurs for both HI-deficient and HI-normal dwarfs. The molecular-to-atomic ratio is more tightly correlated with stellar surface density than metallicity, confirming that the interstellar gas pressure plays a key role in determining the balance between the two gaseous components of the interstellar medium. Virgo dwarfs follow the same linear trend between molecular gas mass and star formation rate as more massive spirals, but gas depletion timescales, $\tau_{dep}$, are not constant and range between 100 Myr and 6 Gyr. The interaction with the Virgo cluster environment is removing the atomic gas and dust components of the dwarfs, but the molecular gas appears to be less affected at the current stage of evolution within the cluster. However, the correlation between HI deficiency and the molecular gas depletion time suggests that the lack of gas replenishment from the outer regions of the disc is lowering the star formation activity.Comment: 19 pages, 11 figures, accepted for publication in Astronomy & Astrophysic

Resilience-Performance Tradeoff Analysis of a Deep Neural Network Accelerator

Nowadays, Deep Neural Networks (DNNs) are one of the most computationally-intensive algorithms because of the (i) huge amount of data to be transferred from/to the memory, and (ii) the huge amount of matrix multiplications to compute. These issues motivate the design of custom DNN hardware accelerators. These accelerators are widely used for low-latency safety-critical applications such as object detection in autonomous cars. Safety-critical applications have to be resilient with respect to hardware faults and Deep Learning (DL) accelerators are subjected to hardware faults that can cause functional failures, potentially leading to catastrophic consequences. Although DNNs possess a certain level of intrinsic resilience, it varies depending on the hardware on which they are run. The intent of the paper is to assess the resilience of a systolic-array-based DNN accelerator in the presence of hardware faults, in order to identify the architectural parameters that may mainly impact the DNN resilience

Climate Justice in the City: Mapping Heat-Related Risk for Climate Change Mitigation of the Urban and Peri-Urban Area of Padua (Italy)

The mitigation of urban heat islands (UHIs) is crucial for promoting the sustainable development of urban areas. Geographic information systems (GISs) together with satellite-derived data are powerful tools for investigating the spatiotemporal distribution of UHIs. Depending on the availability of data and the geographic scale of the analysis, different methodologies can be adopted. Here, we show a complete open source GIS-based methodology based on satellite-driven data for investigating and mapping the impact of the UHI on the heat-related elderly risk (HERI) in the Functional Urban Area of Padua. Thermal anomalies in the territory were mapped by modelling satellite data from Sentinel-3. After a socio-demographic analysis, the HERI was mapped according to five levels of risk. The highest vulnerability levels were localised within the urban area and in three municipalities near Padua, which represent about 20% of the entire territory investigated. In these municipalities, a percentage of elderly people over 20%, a thermal anomaly over 2.4 °C, and a HERI over 0.65 were found. Based on these outputs, it is possible to define nature-based solutions for reducing the UHI phenomenon and promote a sustainable development of cities. Stakeholders can use the results of these investigations to define climate and environmental policies

The WISSH quasars Project: II. Giant star nurseries in hyper-luminous quasars

Studying the coupling between the energy output produced by the central quasar and the host galaxy is fundamental to fully understand galaxy evolution. Quasar feedback is indeed supposed to dramatically affect the galaxy properties by depositing large amounts of energy and momentum into the ISM. In order to gain further insights on this process, we study the SEDs of sources at the brightest end of the quasar luminosity function, for which the feedback mechanism is supposed to be at its maximum. We model the rest-frame UV-to-FIR SEDs of 16 WISE-SDSS Selected Hyper-luminous (WISSH) quasars at 1.8 < z < 4.6 disentangling the different emission components and deriving physical parameters of both the nuclear component and the host galaxy. We also use a radiative transfer code to account for the contribution of the quasar-related emission to the FIR fluxes. Most SEDs are well described by a standard combination of accretion disk+torus and cold dust emission. However, about 30% of them require an additional emission component in the NIR, with temperatures peaking at 750K, which indicates the presence of a hotter dust component in these powerful quasars. We measure extreme values of both AGN bolometric luminosity (LBOL > 10^47 erg/s) and SFR (up to 2000 Msun/yr). A new relation between quasar and star-formation luminosity is derived (LSF propto LQSO^(0.73)) by combining several Herschel-detected quasar samples from z=0 to 4. Future observations will be crucial to measure the molecular gas content in these systems, probe the impact between quasar-driven outflows and on-going star-formation, and reveal the presence of merger signatures in their host galaxies.Comment: 19 pages, 12 figures; Accepted for publication in Astronomy & Astrophysics on June 13, 201

Dati VIIRS-Nightfire per il monitoraggio del gas flaring in Amazzonia: il caso Yasun\ued

L\u2019estrazione di combustibili fossili \ue8 un\u2019attivit\ue0 che ha ormai raggiunto aree remote ad alta diversit\ue0 biologica e culturale, tra le quali desta gran preoccupazione l\u2019espansione della frontiera petrolifera in Amazzonia occidentale, specialmente nella Riserva della Biosfera Yasun\uec (YBR), uno dei luoghi pi\uf9 biodiversi del pianeta e casa ancestrale degli indigeni Waorani. In prossimit\ue0 di questa zona, gli impatti socio-ambientali diretti e indiretti delle varie fasi dell\u2019estrazione petrolifera sono ampiamente documentati. Tra queste attivit\ue0, la distribuzione spaziale e gli impatti ambientali del gas flaring non sono stati ancora investigati a fondo, anche a causa della mancanza di un sistema di monitoraggio e documentazione delle posizioni dei flare e dei volumi di gas bruciato. Negli ultimi anni si sta assistendo per\uf2 a un\u2019inversione di tendenza, grazie allo sviluppo di vari metodi di monitoraggio da remoto, attraverso l\u2019analisi multispettrale da satellite. Lo scopo di questo studio \ue8 mappare l\u2019attivit\ue0 di gas flaring nell\u2019area dello YBR, analizzando diacronicamente e valutando gli impatti potenziali sia sulla biodiversit\ue0 che sulle comunit\ue0 locali. I dati giornalieri prodotti dalla NOAA da gennaio 2017 a marzo 2018, basate sull\u2019elaborazione di immagini dal sensore \u201cVisible Infrared Imaging Radiometric Suite\u201d del satellite Suomi-SNPP per il monitoraggio delle attivit\ue0 di gas flaring, sono stati analizzati e geoprocessati con dati sulle aree protette e comunit\ue0 indigene. Per il corretto posizionamento dei flare, quando possibile, \ue8 stato fatto riferimento ai dataset annuali della NOAA, per i nuovi flare \ue8 stato usato il centroide delle rilevazioni. I risultati preliminari mostrano la presenza di un nuovo sito di flare nel campo petrolifero Tiputini vicino all\u2019 \u201cArea Nucleo\u201d della YBR; tre flare sono stati rilevati nella zona buffer e 19 nella zona di transizione della YBR. spaziale ha inoltre identificato 6 comunit\ue0 indigene in un raggio di 6 Km dai flare. Questo studio rivela l\u2019enorme potenziale degli open data come Nightfire della NOAA per il monitoraggio di aree remote ad elevata importanza per la conservazione della biodiversit\ue0 e dei territori indigeni

Mapping and Monitoring Urban Environment through Sentinel-1 SAR Data: A Case Study in the Veneto Region (Italy)

Focusing on a sustainable and strategic urban development, local governments and public administrations, such as the Veneto Region in Italy, are increasingly addressing their urban and territorial planning to meet national and European policies, along with the principles and goals of the 2030 Agenda for the Sustainable Development. In this regard, we aim at testing a methodology based on a semi-automatic approach able to extract the spatial extent of urban areas, referred to as \u201curban footprint\u201d, from satellite data. In particular, we exploited Sentinel-1 radar imagery through multitemporal analysis of interferometric coherence as well as supervised and non-supervised classi\ufb01cation algorithms. Lastly, we compared the results with the land cover map of the Veneto Region for accuracy assessments. Once properly processed and classi\ufb01ed, the radar images resulted in high accuracy values, with an overall accuracy ranging between 85% and 90% and percentages of urban footprint di\ufb00ering by less than 1%\u20132% with respect to the values extracted from the reference land cover map. These results provide not only a reliable and useful support for strategic urban planning and monitoring, but also potentially identify a solid organizational data\ufb02ow process to prepare geographic indicators that will help answering the needs of the 2030 Agenda (in particular the goal 11 \u201cSustainable Cities and Communities\u201d)

Финансово-экономический механизм функционирования кредитных союзов в Украине

Цель статьи - исследование финансово-экономического механизма функционирования кредитных союзов как альтернативного финансирования населения, что позволяет максимально приблизить финансовые услуги к потребителям, создать надлежащие условия для долгосрочного кредитования с применением современной рыночной инфраструктуры и финансовых инструментов

Investigaciones actuales en ligandos de receptores opiáceos

Relevant developments have been achieved in the last twenty years in the search for opioid agonists and antagonists with selectivity for each receptor subpopulation. Recently, new benzomorphan derivatives have been synthesized and compounds with substituted cyclopropylmethyl functionalities at N-l position showed high affinity and selectivity for K opioid receptor subpopulations. MPCB and CCB were selected as specific K agonists. The affinity ofCCB was two-fold the USO,488H one. Mixed peptide-heterocyclic compounds have been derived from these compounds and important informations on binding processes of K ligands have been obtained.En los últimos veinte años se ha llevado a cabo una intensa investigación sobre la búsqueda de agonistas y antagonistas selectivos de cada subtipo de receptores opiáceos. Recientemente, se han sintetizado nuevos derivados benzomorfánicos y compuestos con restos ciclopropilmetílicos sobre N-l que muestran alta afinidad y selectividad por los receptores K . Los compuestos MPCB y CCB se han seleccionado como agonistas específicos K. La afinidad de CCB es dos veces mayor que la del compuesto USO,488H. De estos compuestos se han derivado interesantes compuestos con estructura de peptidoheterocido y se han obtenido importantes informaciones sobre los procesos de binding a los receptores K

Cohexisting Medullary and Papillary Thyroid Cancer

Purpose: Papillary thyroid carcinomas (PTCs) and medullary thyroid carcinomas (MTCs) have always been considered different in terms of their incidence rates, cell origins, and histopathological features. Simultaneous occurrence of both disease entities is very rare. Methods: We describe a series of cases with simultaneous MTC and PTC occurrences in the thyroid gland. Results: From 2,897 patients (mean age, 49.2±12.5; 81% women) who underwent thyroidectomy for cancer between 2000 and 2015, we reviewed 11 cases of simultaneous occurrence of MTCs and PTCs. Multifocal PTC with simultaneous MTC was detected in 5 of the 11 cases (45%). Of these PTC patients, 2 had 2 foci, 2 had 3 foci, and 1 had 4 foci. There was 1 case of multifocal MTC with solitary PTC. One patient presented with “composite thyroid carcinoma” with mixed features of MTCs and PTCs. Eight patients (72%) presented an association with diffuse lymphocytic thyroiditis. The sizes of the tumors were 1.95±0.23 cm vs. 1.20±0.20 cm for PTCs and MTCs, respectively (P=0.531). The prevalence of extrathyroidal extension was 33.1% vs. 30.2% for PTCs and MTCs, respectively (P=0.282). All patients underwent total thyroidectomy and central neck node dissection. Radio iodine was delivered to 44% of patients. Follow-up review revealed 9 disease-free patients and 1 with local neck recurrence, while 1 patient died due to non-thyroid reasons. Conclusion: There are only 30 reports describing a total of 50 cases in the English literature regarding concurrent PTC and MTC in the same gland. This study represents one of the largest case series. Whether the incidence of another cancer in these patients is coincidental, or due to the possible activation of a common tumorigenic pathway for both follicular and parafollicular thyroid cells, remains to be elucidated

H-ATLAS/GAMA and HeViCS - dusty early-type galaxies in different environments

NKA acknowledges the support of the Science and Technology Facilities Council. LD, RJI and SJM acknowledge support from the European Research Council Advanced Grant COSMICISM. IDL gratefully acknowledges the support of the Flemish Fund for Scientific Research (FWO-Vlaanderen). KR acknowledges support from the European Research Council Starting Grant SEDmorph (P.I. V. Wild). Date of acceptance: 22/05/2015The Herschel Space Observatory has had a tremendous impact on the study of extragalactic dust. Specifically, early-type galaxies (ETG) have been the focus of several studies. In this paper, we combine results from two Herschel studies -a Virgo cluster study Herschel Virgo Cluster Survey (HeViCS) and a broader, low-redshift Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS)/Galaxy and Mass Assembly (GAMA) study -and contrast the dust and associated properties for similar mass galaxies. This comparison is motivated by differences in results exhibited between multiple Herschel studies of ETG. A comparison between consistent modified blackbody derived dust mass is carried out, revealing strong differences between the two samples in both dust mass and dust-to-stellar mass ratio. In particular, the HeViCS sample lacks massive ETG with as high a specific dust content as found in H-ATLAS. This is most likely connected with the difference in environment for the two samples. We calculate nearest neighbour environment densities in a consistent way, showing that H-ATLAS ETG occupy sparser regions of the local Universe, whereas HeViCS ETG occupy dense regions. This is also true for ETG that are not Herschel-detected but are in the Virgo and GAMA parent samples. Spectral energy distributions are fit to the panchromatic data. From these, we find that in H-ATLAS the specific star formation rate anticorrelates with stellar mass and reaches values as high as in our Galaxy. On the other hand HeViCS ETG appear to have little star formation. Based on the trends found here, H-ATLAS ETG are thought to have more extended star formation histories and a younger stellar population than HeViCS ETG.Publisher PDFPeer reviewe