131 research outputs found
Probing the AGN Unification Model at redshift z 3 with MUSE observations of giant Ly nebulae
A prediction of the classic active galactic nuclei (AGN) unification model is
the presence of ionisation cones with different orientations depending on the
AGN type. Confirmations of this model exist for present times, but it is less
clear in the early Universe. Here, we use the morphology of giant Ly
nebulae around AGNs at redshift z3 to probe AGN emission and therefore
the validity of the AGN unification model at this redshift. We compare the
spatial morphology of 19 nebulae previously found around type I AGNs with a new
sample of 4 Ly nebulae detected around type II AGNs. Using two
independent techniques, we find that nebulae around type II AGNs are more
asymmetric than around type I, at least at radial distances ~physical kpc
(pkpc) from the ionizing source. We conclude that the type I and type II AGNs
in our sample show evidence of different surrounding ionising geometries. This
suggests that the classical AGN unification model is also valid for
high-redshift sources. Finally, we discuss how the lack of asymmetry in the
inner parts (r30 pkpc) and the associated high values of the HeII to
Ly ratios in these regions could indicate additional sources of (hard)
ionizing radiation originating within or in proximity of the AGN host galaxies.
This work demonstrates that the morphologies of giant Ly nebulae can be
used to understand and study the geometry of high redshift AGNs on
circum-nuclear scales and it lays the foundation for future studies using much
larger statistical samples.Comment: 15 pages, 13 figures, accepted for publication in MNRA
Assessment of Performance of Manufacturing Procedures in a Unit for Production of Investigational Anticancer Agents, Using a Mixed Effects Analysis
Efficient loading of dendritic cells following cryo and radiofrequency ablation in combination with immune modulation induces anti-tumour immunity
Dendritic cells (DC) are professional antigen-presenting cells that play a pivotal role in the induction of immunity. Ex vivo-generated, tumour antigen-loaded mature DC are currently exploited as cancer vaccines in clinical studies. However, antigen loading and maturation of DC directly in vivo would greatly facilitate the application of DC-based vaccines. We formerly showed in murine models that radiofrequency-mediated tumour destruction can provide an antigen source for the in vivo induction of anti-tumour immunity, and we explored the role of DC herein. In this paper we evaluate radiofrequency and cryo ablation for their ability to provide an antigen source for DC and compare this with an ex vivo-loaded DC vaccine. The data obtained with model antigens demonstrate that upon tumour destruction by radiofrequency ablation, up to 7% of the total draining lymph node (LN) DC contained antigen, whereas only few DC from the conventional vaccine reached the LN. Interestingly, following cryo ablation the amount of antigen-loaded DC is almost doubled. Analysis of surface markers revealed that both destruction methods were able to induce DC maturation. Finally, we show that in situ tumour ablation can be efficiently combined with immune modulation by anti-CTLA-4 antibodies or regulatory T-cell depletion. These combination treatments protected mice from the outgrowth of tumour challenges, and led to in vivo enhancement of tumour-specific T-cell numbers, which produced more IFN-γ upon activation. Therefore, in situ tumour destruction in combination with immune modulation creates a unique, ‘in situ DC-vaccine' that is readily applicable in the clinic without prior knowledge of tumour antigens
Spectral Stacking of Radio-Interferometric Data
Mapping molecular line emission beyond the bright low-J CO transitions is
still challenging in extragalactic studies, even with the latest generation of
(sub-)mm interferometers, such as ALMA and NOEMA. We summarise and test a
spectral stacking method that has been used in the literature to recover
low-intensity molecular line emission, such as HCN(1-0), HCO+(1-0), and even
fainter lines in external galaxies. The goal is to study the capabilities and
limitations of the stacking technique when applied to imaged interferometric
observations. The core idea of spectral stacking is to align spectra of the low
S/N spectral lines to a known velocity field calculated from a higher S/N line
expected to share the kinematics of the fainter line, e.g., CO(1-0) or 21-cm
emission. Then these aligned spectra can be coherently averaged to produce
potentially high S/N spectral stacks. Here, we use imaged simulated
interferometric and total power observations at different signal-to-noise
levels, based on real CO observations. For the combined interferometric and
total power data, we find that the spectral stacking technique is capable of
recovering the integrated intensities even at low S/N levels across most of the
region where the high S/N prior is detected. However, when stacking
interferometer-only data for low S/N emission, the stacks can miss up to 50% of
the emission from the fainter line. A key result of this analysis is that the
spectral stacking method is able to recover the true mean line intensities in
low S/N cubes and to accurately measure the statistical significance of the
recovered lines. To facilitate the application of this technique we provide a
public Python package, called PyStacker.Comment: 10 pages, 10 figures, accepted for pub in A&A, Apr 28, 202
Ковчег Ноя: рух матерії у Сонячній системі та на ядерних рівнях Землі
У Стародавньому світі пророку Мойсею було відкрито таємницю створення світу. Як науковий геній свого
часу, Мойсей зашифрував у алегоричну форму в родоводі Адама і Потопі прикладну науку про будову
ядра Землі, Сонячної системи і рухи космічної водневої і сонячної вуглецевої матерій (енергій) крізь Землю.В Древнем мире пророку Моисею была открыта тайна создания мира. Как научный гений своего времени
Моисей зашифровал в форму аллегории в родословной Адама и Потопе прикладную науку о строении ядра
Земли, Солнечной системы и движениях космической водородной и солнечной углеродной материи (энергии)
сквозь Землю.In the Ancient history the mystery of the Creation of the world was revealed to the Prophet Moses. As a scientific
genius of that époque Moses codified in allegoric way in the genealogy of Adam and The Flood the applied science
on the structure of the Earth core, of the Solar System and motion of cosmic hydrogenous and solar carbonic substance
(energy) through the Earth
Resolved low-J CO excitation at 190 parsec resolution across NGC 2903 and NGC 3627
The low- rotational transitions of CO are commonly used to trace
the distribution of molecular gas in galaxies. Their ratios are sensitive to
excitation and physical conditions in the molecular gas. Spatially resolved
studies of CO ratios are still sparse and affected by flux calibration
uncertainties, especially since most do not have high angular resolution or do
not have short-spacing information and hence miss any diffuse emission. We
compare the low- CO ratios across the disk of two massive, star-forming
spiral galaxies NGC2903 and NGC3627 to investigate whether and how local
environments drive excitation variations at GMC scales. We use Atacama Large
Millimeter Array (ALMA) observations of the three lowest- CO transitions at
a common angular resolution of 4 (190pc). We measure median line ratios of
, , and
across the full disk of NGC3627. We see clear CO
line ratio variation across the galaxy consistent with changes in temperature
and density of the molecular gas. In particular, toward the center, ,
, and increase by 35\%, 50\%, and 66\%, respectively compared
to their average disk values. The overall line ratio trends suggest that
CO(3-2) is more sensitive to changes in the excitation conditions than the two
lower- transitions. Furthermore, we find a similar radial trend in
NGC2903, albite a larger disk-wide average of . We conclude that the CO low- line
ratios vary across environments in such a way that they can trace changes in
the molecular gas conditions, with the main driver being changes in
temperature.Comment: accepted for publication in MNRAS, 17 pages, 16 figure
Californian Science Students' Perceptions of their Classoom Learning Environments.
This study utilised the What Is Happening In this Class (WIHIC) questionnaire to examine factors that influence Californian student perceptions of their learning environment. Data were collected from 665 USA middle school science students in 11 Californian schools. Several background variables were included in the study to investigate their effects on students’ perceptions, such as student and teacher gender, student ethnic background and socio-economic status (SES), and student age. Class and school variables, such as class ethnic composition, class size and school socioeconomic status were also collected. A hierarchical analysis of variance was conducted to investigate separate and joint effects of these variables. Results from this study indicate that some scales of the WIHIC are more inclined to measure personal or idiosyncratic features of student perceptions of their learning environment whereas other scales contain more variance at the class level. Also, it was found that different variables affect different scale scores. A variable that consistently affected students' perceptions, regardless of the element of interest in the learning environment was student gender. Generally speaking girls perceived their learning environment more positively than did boys
Wide-field CO isotopologue emission and the CO-to-H factor across the nearby spiral galaxy M101
Carbon monoxide (CO) emission is the most widely used tracer of the bulk
molecular gas in the interstellar medium (ISM) in extragalactic studies. The
CO-to-H conversion factor, , links the observed CO
emission to the total molecular gas mass. However, no single prescription
perfectly describes the variation of across all environments
across galaxies as a function of metallicity, molecular gas opacity, line
excitation, and other factors. Using resolved spectral line observations of CO
and its isotopologues, we can constrain the molecular gas conditions and link
them to a variation in the conversion factor. We present new IRAM 30-m 1mm and
3mm line observations of CO, CO, and CO} across the nearby
galaxy M101. Based on the CO isotopologue line ratios, we find that selective
nucleosynthesis and opacity changes are the main drivers of the variation in
the line emission across the galaxy. Furthermore, we estimated using different approaches, including (i) the dust mass surface
density derived from far-IR emission as an independent tracer of the total gas
surface density and (ii) LTE-based measurements using the optically thin
CO(1-0) intensity. We find an average value of across the galaxy,
with a decrease by a factor of 10 toward the 2 kpc central region. In contrast,
we find LTE-based values are lower by a factor of 2-3 across the disk relative
to the dust-based result. Accounting for variations, we found
significantly reduced molecular gas depletion time by a factor 10 in the
galaxy's center. In conclusion, our result suggests implications for commonly
derived scaling relations, such as an underestimation of the slope of the
Kennicutt Schmidt law, if variations are not accounted for.Comment: Accepted for publication in A&A, 25 pages, 15 figure
The safety and feasibility of extracorporeal high-intensity focused ultrasound (HIFU) for the treatment of liver and kidney tumours in a Western population
High-intensity focused ultrasound (HIFU) provides a potential noninvasive alternative to conventional therapies. We report our preliminary experience from clinical trials designed to evaluate the safety and feasibility of a novel, extracorporeal HIFU device for the treatment of liver and kidney tumours in a Western population. The extracorporeal, ultrasound-guided Model-JC Tumor Therapy System (HAIFU™ Technology Company, China) has been used to treat 30 patients according to four trial protocols. Patients with hepatic or renal tumours underwent a single therapeutic HIFU session under general anaesthesia. Magnetic resonance imaging 12 days after treatment provided assessment of response. The patients were subdivided into those followed up with further imaging alone or those undergoing surgical resection of their tumours, which enabled both radiological and histological assessment. HIFU exposure resulted in discrete zones of ablation in 25 of 27 evaluable patients (93%). Ablation of liver tumours was achieved more consistently than for kidney tumours (100 vs 67%, assessed radiologically). The adverse event profile was favourable when compared to more invasive techniques. HIFU treatment of liver and kidney tumours in a Western population is both safe and feasible. These findings have significant implications for future noninvasive image-guided tumour ablation
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