In this paper we present the results of a systematic investigation of an entire population of predominately starless dust cores within a single molecular cloud, the Pipe Nebula. Analysis of ...extinction data shows the cores to be dense objects characterized by a narrow range of density with a median value of alpha (H sub(2)) = 7 x 10t super(3), The nonthermal velocity dispersions measured in molecular emission lines are found to be subsonic for the large majority of the cores and show no correlation with core mass (or size). Thermal pressure is found to be the dominate source of internal gas pressure and support for most of the core population. The total internal pressures of the cores are found to be roughly independent of core mass over the entire (0.2-20 M unk) range of the core mass function (CMF) indicating that the cores are in pressure equilibrium with an external source of pressure. This external pressure is most likely provided by the weight of the surrounding molecular cloud. Most of the cores appear to be pressure confined, gravitationally unbound entities whose fundamental physical properties are determined by only a few factors, which include self-gravity, gas temperature, and the simple requirement of pressure equilibrium with the surrounding environment. The entire core population is found to be characterized by a single critical Bonnor-Ebert mass of approximately 2 M unk. This mass coincides with the characteristic mass of the Pipe CMF suggesting that the CMF (and ultimately the stellar IMF) has its origin in the physical process of thermal fragmentation in a pressurized medium.
Diabet. Med. 29, 622–627 (2012)
Objective Previous studies have highlighted the associations between abdominal, cardiac or total fat accumulation and cardiovascular disease. The aim of this study ...was to investigate the impact of different ectopic fat depots on measurements of metabolic dysfunction and cardiovascular disease risk.
Methods Using magnetic resonance imaging in 113 subjects, we measured abdominal (visceral and subcutaneous) and cardiac (epicardial and extra‐pericardial) fat depots and examined their association with overall (BMI) and abdominal obesity (waist circumference), dyslipidaemia (triglycerides, total and HDL cholesterol), glucose tolerance (by an oral glucose tolerance test) and insulin sensitivity, blood pressure and 10‐year coronary heart disease risk by Framingham score.
Results Fat accumulation was proportional to the degree of obesity, with body fat ranging from 14 to 33 kg, visceral fat from 0.8 to 1.8 kg and cardiac fat from 134 to 236 g. Most cardiac fat (70% on average) was extra‐pericardial, with a wide variability for both cardiac depots (epicardial: 172–2008 mm2; extra‐pericardial: 100–5056 mm2). Only visceral and extra‐pericardial fat, but not epicardial or subcutaneous fat, could discriminate between subjects with three or more factors of the metabolic syndrome or medium‐to‐high coronary heart disease risk score. Controlling for gender and BMI by multivariable analysis, the best marker of reduced insulin sensitivity was visceral fat (partial r = −0.35); extra‐pericardial fat was the closest associate of increased blood pressure (partial r = 0.26) and both extra‐pericardial and visceral fat clustered with hypertriglyceridaemia (partial r = 0.29 and 0.24; both P < 0.02).
Conclusion Increased epicardial fat per se does not necessarily translate into presence or prediction of disease. In contrast, increased deposition of visceral abdominal and extra‐pericardial mediastinal fat are both associated with an enhanced cardiovascular disease risk profile.
We present a high-resolution dissection of the two-dimensional total mass distribution in the core of the Hubble Frontier Fields galaxy cluster MACS J0416.1−2403, at z = 0.396. We exploit HST/WFC3 ...near-IR (F160W) imaging, VLT/Multi Unit Spectroscopic Explorer spectroscopy, and Chandra data to separate the stellar, hot gas, and dark-matter mass components in the inner 300 kpc of the cluster. We combine the recent results of our refined strong lensing analysis, which includes the contribution of the intracluster gas, with the modeling of the surface brightness and stellar mass distributions of 193 cluster members, of which 144 are spectroscopically confirmed. We find that, moving from 10 to 300 kpc from the cluster center, the stellar to total mass fraction decreases from 12% to 1% and the hot gas to total mass fraction increases from 3% to 9%, resulting in a baryon fraction of approximatively 10% at the outermost radius. We measure that the stellar component represents ∼30%, near the cluster center, and 15%, at larger clustercentric distances, of the total mass in the cluster substructures. We subtract the baryonic mass component from the total mass distribution and conclude that within 30 kpc (∼3 times the effective radius of the brightest cluster galaxy) from the cluster center the surface mass density profile of the total mass and global (cluster plus substructures) dark-matter are steeper and that of the diffuse (cluster) dark-matter is shallower than an NFW profile. Our current analysis does not point to a significant offset between the cluster stellar and dark-matter components. This detailed and robust reconstruction of the inner dark-matter distribution in a larger sample of galaxy clusters will set a new benchmark for different structure formation scenarios.
•Short term evaluation framework of the Social Innovation (SI) is proposed.•Quantitative indicators are based on the comparison of two groups of farmers.•SI caused network reconfiguration in farming ...communities creating new relations.•SI transformed acquaintance relations into active and permanent relations.•The network intervention enhanced entrepreneurship for new business formation.
The marginalised rural communities are characterised by societal challenges, such as isolation, lack of job opportunities, land abandonment, low quality of life and generally low education. Social Innovation (SI) initiatives may represent an opportunity to strengthen relationships among the members of rural community, by means of the alteration of the existing social networks. In this way, more exchange of information is expected, paving the way for the creation of professional collaborations among firms and other actors. This paper aims at proposing a short-term evaluation framework of effectiveness of a SI initiative in terms of reconfiguration of the social network structure. The described empirical case study is VàZapp’, a rural hub located in Southern Italy, which provides innovative solutions to activate social relations amongst farmers, altering hence their network. A well-referenced SI theoretical model, developed within the H2020 project SIMRA (Social Innovation in Marginalised Rural Areas), and the methodology of Social Network Analysis (SNA) were used to verify and measure quantitative and qualitative indicators affected by network intervention activated by VàZapp’ initiative. Results show that this SI initiative worked effectively, leading to a +308% in the number of relations and +250% in social network density. In addition, an evident improvement in the quality of the social relations was found, especially in cases where there are direct engagements within VàZapp’. Outcomes suggest that supporting and promoting SI initiatives could become a central discussion point for the rethinking of rural development policies focused on regeneration of social relations’ structure.
Autosomal dominant polycystic kidney disease (PKD) is characterized by cyst formation and growth, which are partially driven by abnormal proliferation of tubular cells. Proproliferative mechanistic ...target of rapamycin (mTOR) complexes 1 and 2 (mTORC1 and mTORC2) are activated in the kidneys of mice with PKD. Sirolimus indirectly inhibits mTORC1. Novel mTOR kinase inhibitors directly inhibit mTOR kinase, resulting in the inhibition of mTORC1 and mTORC2. The aim of the present study was to determine the effects of sirolimus versus the mTOR kinase inhibitor torin2 on cyst growth and kidney function in the
p.R3277C (
) mouse model, a hypomorphic
model orthologous to the human condition, and to determine the effects of sirolimus versus torin2 on mTORC1 and mTORC2 signaling in
cells and in the kidneys of
mice. In vitro, both inhibitors reduced mTORC1 and mTORC2 phosphorylated substrates and negatively impacted cellular metabolic activity, as measured by MTT assay.
mice were treated with sirolimus or torin2 from 50 to 120 days of age. Torin2 was as effective as sirolimus in decreasing cyst growth and improving loss of kidney function. Both sirolimus and torin2 decreased phosphorylated S6 protein, phosphorylated eukaryotic translation initiation factor 4E-binding protein 1, phosphorylated Akt, and proliferation in
kidneys. In conclusion, torin2 and sirolimus were equally effective in decreasing cyst burden and improving kidney function and mediated comparable effects on mTORC1 and mTORC2 signaling and proliferation in the
kidney.
Context.
The next generation of extensive and data-intensive surveys are bound to produce a vast amount of data, which can be efficiently dealt with using machine-learning and deep-learning methods ...to explore possible correlations within the multi-dimensional parameter space.
Aims.
We explore the classification capabilities of convolution neural networks (CNNs) to identify galaxy cluster members (CLMs) by using
Hubble
Space Telescope (HST) images of fifteen galaxy clusters at redshift 0.19 ≲
z
≲ 0.60, observed as part of the CLASH and
Hubble
Frontier Field programmes.
Methods.
We used extensive spectroscopic information, based on the CLASH-VLT VIMOS programme combined with MUSE observations, to define the knowledge base. We performed various tests to quantify how well CNNs can identify cluster members on ht basis of imaging information only. Furthermore, we investigated the CNN capability to predict source memberships outside the training coverage, in particular, by identifying CLMs at the faint end of the magnitude distributions.
Results.
We find that the CNNs achieve a purity-completeness rate ≳90%, demonstrating stable behaviour across the luminosity and colour of cluster galaxies, along with a remarkable generalisation capability with respect to cluster redshifts. We concluded that if extensive spectroscopic information is available as a training base, the proposed approach is a valid alternative to catalogue-based methods because it has the advantage of avoiding photometric measurements, which are particularly challenging and time-consuming in crowded cluster cores. As a byproduct, we identified 372 photometric cluster members, with mag(
F
814) < 25, to complete the sample of 812 spectroscopic members in four galaxy clusters RX J2248-4431, MACS J0416-2403, MACS J1206-0847 and MACS J1149+2223.
Conclusions.
When this technique is applied to the data that are expected to become available from forthcoming surveys, it will be an efficient tool for a variety of studies requiring CLM selection, such as galaxy number densities, luminosity functions, and lensing mass reconstruction.
Isomeric bis(aldiminium) salts with a 1,4-cyclohexylene framework were synthesized. The first isolable bis(CAAC) was prepared from the
-stereoisomer and its ditopic ligand competency was proven by ...conversion to iridium(I) and rhodium(I) complexes. Upon deprotonation, the
-isomer yielded an electron rich olefin
a classic, proton-catalyzed pathway. The CC bond formation from the desired
-bis(CAAC) was shown to be thermodynamically very favorable and to involve a small activation barrier. Compounds that can be described as insertion products of the
-bis(CAAC) into the E-H bonds of NH
, CH
CN and H
O were also identified.
Context.Observations of the cosmic microwave background, light element abundances, large-scale distribution of galaxies, and distant supernovae are the primary tools for determining the cosmological ...parameters that define the global structure of the Universe. Aims.Here we illustrate how the combination of observations related to strong gravitational lensing and stellar dynamics in elliptical galaxies offers a simple and promising way to measure the cosmological matter and dark-energy density parameters. Methods.A gravitational lensing estimate of the mass enclosed inside the Einstein circle can be obtained by measuring the Einstein angle, once the critical density of the system is known. A model-dependent dynamical estimate of this mass can also be obtained by measuring the central velocity dispersion of the stellar component. By assuming the well-tested homologous $1/r^{2}$ (isothermal) profile for the total (luminous+dark) density distribution in elliptical galaxies acting as lenses, these two mass measurements can be properly compared. Thus, a relation between the Einstein angle and the central stellar velocity dispersion is derived, and the cosmological matter and the dark-energy density parameters can be estimated from this. Results.We determined the accuracy of the cosmological parameter estimates by means of simulations that include realistic measurement uncertainties on the relevant quantities. Interestingly, the expected constraints on the cosmological parameter plane are complementary to those coming from other observational techniques. Then, we applied the method to the recent data sets of the Sloan Lens ACS (SLACS) and the Lenses Structure and Dynamics (LSD) Surveys, and showed that the concordance value between 0.7 and 0.8 for the dark-energy density parameter is included in our 99% confidence regions. Conclusions.The small number of lenses available to date prevents us from precisely determining the cosmological parameters, but it still proves the feasibility of the method. When applied to samples made of hundreds of lenses that are expected to become available from forthcoming deep and wide surveys, this technique will be an important alternative tool for measuring the geometry of the Universe.
Choice behavior is rational if it is based on the maximization of some context-independent preference relation. This study re-examines the questions of implementation theory in a setting where ...players’ choice behavior need not be rational and coalition formation must be taken into account. Our model implies that with non-rational players, the formation of groups greatly affects the design exercise. As a by-product, we also propose a notion of behavioral efficiency and we compare it with existing notions.
Porous ceramic materials are of considerable interest for a variety of chemical and industrial applications in extremely harsh conditions, particularly at very high temperatures for long time ...periods. A combined gel-casting-fugitive phase process employing agar as a natural gelling agent and polyethylene spheres as pore formers was exploited to produce porous ceramic bodies. Alumina and alumina–zirconia powders were used to prepare samples having a porosity of about 65–70–75vol%. The composite powder was produced by a surface modification route, i.e. by coating a well-dispersed alpha-alumina powder with a zirconium chloride aqueous solution. On thermal treatment, ultra-fine tetragonal zirconia grains were formed on the surface of the alumina particles. SEM observations and image analysis were used to characterize the microstructure of porous samples and uniaxial compressive tests were carried out to measure their mechanical behavior.
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