scholarly journals Resolving the nuclear dust distribution of the Seyfert 2 galaxy NGC 3081

2011 ◽  
Vol 417 (1) ◽  
pp. L46-L50 ◽  
Author(s):  
C. Ramos Almeida ◽  
M. Sánchez-Portal ◽  
A. M. Pérez García ◽  
J. A. Acosta-Pulido ◽  
M. Castillo ◽  
...  
2019 ◽  
Vol 1 (1) ◽  
pp. 110-114
Author(s):  
Angélica María Hernández Fernández ◽  
José Antonio Flores Vargas

Introduction. Leukocytoclastic vasculitis (LV) is the presence of leukocytoclasis (fragmentation of the nuclei of neutrophils or "nuclear dust") in the wall of small vessels and around them. Case Presentation. A 37-yearold female patient with a diagnosis of thrombocytopenic purpura who starts treatment with ceftazidime and phenytoin, which causes LV. Conclusions. The case presented is associated with pharmacological etiology because the patient does not present a concomitant etiological condition.


2020 ◽  
Vol 499 (4) ◽  
pp. 5732-5748 ◽  
Author(s):  
Rahul Kannan ◽  
Federico Marinacci ◽  
Mark Vogelsberger ◽  
Laura V Sales ◽  
Paul Torrey ◽  
...  

ABSTRACT We present a novel framework to self-consistently model the effects of radiation fields, dust physics, and molecular chemistry (H2) in the interstellar medium (ISM) of galaxies. The model combines a state-of-the-art radiation hydrodynamics module with a H  and He  non-equilibrium thermochemistry module that accounts for H2 coupled to an empirical dust formation and destruction model, all integrated into the new stellar feedback framework SMUGGLE. We test this model on high-resolution isolated Milky-Way (MW) simulations. We show that the effect of radiation feedback on galactic star formation rates is quite modest in low gas surface density galaxies like the MW. The multiphase structure of the ISM, however, is highly dependent on the strength of the interstellar radiation field. We are also able to predict the distribution of H2, that allow us to match the molecular Kennicutt–Schmidt (KS) relation, without calibrating for it. We show that the dust distribution is a complex function of density, temperature, and ionization state of the gas. Our model is also able to match the observed dust temperature distribution in the ISM. Our state-of-the-art model is well-suited for performing next-generation cosmological galaxy formation simulations, which will be able to predict a wide range of resolved (∼10 pc) properties of galaxies.


Gefahrstoffe ◽  
2020 ◽  
Vol 80 (09) ◽  
pp. 344-348
Author(s):  
M. Clauß ◽  
S. Linke ◽  
A. C. Springorum

The particle size distribution of airborne bacterial conglomerates is an important factor in calculating possible spread distances of the bacteria over the air. Therefore, a size-selective collection system based on an emission impinger was developed to compare the distribution of total bacteria and staphylococci in particle fractions PM2.5, PM10 and total dust in the emission of two fattening pig stables. Mean emissions of 7.2 × 104 cfu/m³ total bacteria, 6.1 × 104 cfu/m³ staphylococci and 2.8 × 106 cells/m3 measured. About 30% of total bacteria and staphylococci were found in the PM2.5 particle size fraction and about 60% in PM10. The average dust distribution was 80% PM10 and 60% PM2.5. The results show that airborne bacteria from fattening pig units mainly occur on larger particles and do not correlate with dust fractions. The found conditions should be considered in future dispersion modelling.


2011 ◽  
Vol 59 (14) ◽  
pp. 1795-1803 ◽  
Author(s):  
Vladimir Pines ◽  
Marianna Zlatkowski ◽  
Arnon Chait

2012 ◽  
Vol 12 (21) ◽  
pp. 10545-10567 ◽  
Author(s):  
P. Nabat ◽  
F. Solmon ◽  
M. Mallet ◽  
J. F. Kok ◽  
S. Somot

Abstract. The present study investigates the dust emission and load over the Mediterranean basin using the coupled chemistry–aerosol–regional climate model RegCM-4. The first step of this work focuses on dust particle emission size distribution modeling. We compare a parameterization in which the emission is based on the individual kinetic energy of the aggregates striking the surface to a recent parameterization based on an analogy with the fragmentation of brittle materials. The main difference between the two dust schemes concerns the mass proportion of fine aerosol that is reduced in the case of the new dust parameterization, with consequences for optical properties. At the episodic scale, comparisons between RegCM-4 simulations, satellite and ground-based data show a clear improvement using the new dust distribution in terms of aerosol optical depth (AOD) values and geographic gradients. These results are confirmed at the seasonal scale for the investigated year 2008. This change of dust distribution has sensitive impacts on the simulated regional dust budget, notably dry dust deposition and the regional direct aerosol radiative forcing over the Mediterranean basin. In particular, we find that the new size distribution produces a higher dust deposition flux, and smaller top of atmosphere (TOA) dust radiative cooling. A multi-annual simulation is finally carried out using the new dust distribution over the period 2000–2009. The average SW radiative forcing over the Mediterranean Sea reaches −13.6 W m−2 at the surface, and −5.5 W m−2 at TOA. The LW radiative forcing is positive over the basin: 1.7 W m−2 on average over the Mediterranean Sea at the surface, and 0.6 W m−2 at TOA.


2002 ◽  
Vol 46 (2-7) ◽  
pp. 187-192 ◽  
Author(s):  
A.R. Martel ◽  
S.A. Baum ◽  
W.B. Sparks ◽  
J.A. Biretta ◽  
G. Verdoes Kleijn ◽  
...  

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Lirong Wu ◽  
Hongxuan Chen ◽  
Jiamin Li ◽  
Shican Fu ◽  
Yuyan Zhuang

The dust concentration changing regularities are the basis to take dust depression measures, which is greatly influenced by the airflow. In the software of FLUENT, the value of ventilation velocity is set as a constant, which cannot express the real ventilation. According to the flow characteristics of the sublayer and data from Nicholas’ experiment, the ventilation velocity distribution formula of sublayer in the inlet section of fully mechanized caving coal face is deduced. The boundary condition of velocity is given by UDF. Taking the 3top1110 fully mechanized caving coal face as an example, the dust distribution in the process of coal mining and hydraulic support shifting was studied. According to the dust-spray coupling experiment, three types of nozzle are chosen based on the efficiency of dust suppression. Combining the dust migration rule and the characteristics of nozzles, the negative pressure-secondary dust suppression devices of spray were developed and applied. And the above measures have lowered the dust concentration effectively.


2013 ◽  
Vol 8 (S299) ◽  
pp. 90-93
Author(s):  
Nienke van der Marel ◽  
Ewine F. van Dishoeck ◽  
Simon Bruderer ◽  
Til Birnstiel ◽  
Paola Pinilla ◽  
...  

AbstractPlanet formation and clearing of protoplanetary disks is one of the long standing problems in disk evolution theory. The best test of clearing scenarios is observing systems that are most likely to be actively forming planets: the transitional disks with large inner dust cavities. We present the first results of our ALMA (Atacama Large Millimeter/submillimeter Array) Cycle 0 program using Band 9, imaging the Herbig Ae star Oph IRS 48 in CO 6−5 and the submillimeter continuum in the extended configuration. The resulting ~0.2″ spatial resolution completely resolves the cavity of this disk in the gas and the dust. The gas cavity of IRS 48 is half as large as the dust cavity, ruling out grain growth and photoevaporation as the primary cause of the truncation. On the other hand, the continuum emission reveals an unexpected large azimuthal asymmetry and steep edges in the dust distribution along the ring, suggestive of dust trapping. We will discuss the implications of the combined gas and dust distribution for planet formation at a very early stage. This is one of the first transition disks with spatially resolved gas inside the cavity, demonstrating the superb capabilities of the Band 9 receivers.


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