A new approach to multiwavelength associations of astronomical sources

One of the biggest problems faced by current and next-generation astronomical surveys is trying to produce large numbers of accurate cross-identifications across a range of wavelength regimes with varying data quality and positional uncertainty. Until recently, simple spatial 'nearest neighbour' associations have been sufficient for most applications. However as advances in instrumentation allow more sensitive images to be made, the rapid increase in the source density has meant that source confusion across multiple wavelengths is a serious problem. The field of far-IR and sub-mm astronomy has been particularly hampered by such problems. The poor angular resolution of current sub-mm and far-IR instruments is such that in a lot of cases, there are multiple plausible counterparts for each source at other wavelengths. Here we present a new automated method of producing associations between sources at different wavelengths using a combination of spatial and spectral energy distribution information set in a Bayesian framework. Testing of the technique is performed on both simulated catalogues of sources from GaLICS and real data from multiwavelength observations of the Subaru-XMM Deep Field. It is found that a single figure of merit, the Bayes factor, can be effectively used to describe the confidence in the match. Further applications of this technique to future Herschel data sets are discusse

A Simplified Model for Estimating Household Air Pollution in Challenging Contexts: A Case Study from Ghana

Almost three billion people rely primarily on inefficient and polluting cooking systems worldwide. Household air pollution is a direct consequence of this practice, and it is annually associated with millions of premature deaths and diseases, mainly in low- and lower-middle-income countries. The use of improved cookstoves often represents an appropriate solution to reduce such health risks. However, in the distribution of such units, it can be necessary to prioritize the beneficiaries. Thus, in this study, we conducted field research involving five rural villages in the Northern part of Ghana, where using three-stone fires or rural stoves was common. Concentrations of PM2.5, PM10, and carbon monoxide (CO) were measured indoors and outdoors. Considering each field mission lasted less than 24 h, assumptions were made so as to calculate the average pollutant concentrations in 24 h through a new, simplified equation that combined efficiency and cost-savings by shortening field assessments. The obtained values were compared with international guidelines. The results showed that PM2.5 and PM10 limits were overstepped in two villages, which should thus be prioritized. However, further research will be necessary to strengthen and validate our proposed equation, which must be seen as a starting point

Solid Waste Management in Rural Communities of Developing Countries: An Overview of Challenges and Opportunities

Solid waste management (SWM) in rural areas of many low- and middle-income countries (LMICs) represents a critical and underrated topic. However, almost half of the world's population still lives in rural areas and an adequate SWM is crucial in reducing environmental and health threats. A lack of knowledge and appropriate tools often leads to inappropriate practices such as waste dumping and uncontrolled burning. However, appropriate methods can transform waste into resources and even guarantee a revenue source. This manuscript provides an overview of the state of the knowledge characterising SWM in rural communities of LMICs, analysing common practices and principal issues. Different solid waste fractions are considered. Virtuous approaches are presented, taking into account recent sustainable solutions. Considering that a relevant part of the world population is still living in rural areas, the benefits associated with an appropriate SWM may be enormous. Such activities may improve local conditions from social, environmental and health perspectives; furthermore, they may have a global impact on facing climate change and environmental pollution

Effect of chestnut tannins on the root-knot nematode Meloidogyne javanica

Among the natural products extracted from plants, tanninshave been reported to possess antihelmintic propertiesespecially for gastrointestinal nematodes in ruminants.Also, they are toxic to a wide range of fungi, bacteria andyeasts. Therefore, an in vitro and a glasshouse pot experimentswere undertaken to evaluate the effect of chestnuttannins on the control of the root-knot nematode Meloidogynejavanica. In the in vitro experiment, different tanninconcentrations in a geometric scale (from 0.32 to 20.48g/l), were tested for their effect on hatching of the nematode,whereas in the pot experiment, 100, 250 and 450g/m2 of tannins in aqueous solutions, were used in pots attransplant or at transplant and two weeks later for theireffect on nematode control. In both experiments treatmentswere compared to untreated and fenamiphos-treated controls.In vitro a nematostatic effect of tannins was observed,whereas in the pot experiment a significant reductionof eggs and juveniles/g root, total population densityand reproduction rates of the nematode were recorded. Theanatomical changes induced by M. javanica in tomatoroots treated with tannins did not differ from those producedby this and other Meloidogyne species on varioushosts reported earlier

FT-IR Investigation of Methoxy Substituted Benzenes Adsorbed on Solid Acid Catalysts

The nature of the interaction on two different catalysts (zeolite BEA and \u3b3-alumina) of some aromatic substrates, 1,2-methylendioxybenzene, 1,2-ethylendioxybenzene, and 1,2-dimethoxybenzene, have been investigated by FT-IR spectroscopy. FT-IR data suggest that the adsorption of 1,2-methylendioxybenzene occurs through oxygen atoms and the molecule maintains the original puckered conformation, whereas the planar structure due to the absence of a fused ring in the case of 1,2- dimethoxybenzene and the twisted conformation of 1,2-ethylendioxybenzene cause an orientation of the molecules parallel to the catalyst surface, with the benzene ring directly interacting to it. The puckered conformation of MDB leads the benzene ring to be electron-deficient, then deactivated toward alkylation, such as confirmed by the obtained catalytic results, which show that MDB is totally not reactive using the investigated heterogeneous catalysts, while in the traditional homogeneous system shows a reactivity comparable to the other considered substrates

Offset-free economic mpc based on modifier adaptation: Investigation of several gradient-estimation techniques

Various offset-free economic model predictive control schemes that include a disturbance model and the modifier-adaptation principle have been proposed in recent years. These schemes are able to reach plant optimality asymptotically even in the presence of plant–model mismatch. All schemes are affected by a major issue that is common to all modifier-adaptation formulations, namely, plant optimality (note that convergence per se does not require perfect plant gradients) requires perfect knowledge of static plant gradients, which is a piece of information not known in most practical applications. To address this issue, we present two gradient-estimation techniques, one based on Broyden’s update and the other one on linear regression. We apply these techniques for the estimation of either the plant gradients or the modifiers directly. The resulting economic MPC schemes are tested in a simulation and compared on two benchmark examples of different complexity with respect to both convergence speed and robustness to measurement noise

The Lockman Hole Project: new constraints on the sub-mJy source counts from a wide-area 1.4 GHz mosaic

This paper is part of a series discussing the results obtained in the framework of a wide international collaboration - the Lockman Hole Project - aimed at improving the extensive multiband coverage available in the Lockman Hole region, through novel deep, wide-area, multifrequency (60, 150, 350 MHz, and 1.4 GHz) radio surveys. This multifrequency, multi-band information will be exploited to get a comprehensive view of star formation and active galactic nucleus activities in the high-redshift Universe from a radio perspective. In this paper, we present novel 1.4 GHz mosaic observations obtained with the Westerbork Synthesis Radio Telescope. With an area coverage of 6.6 deg2, this is the largest survey reaching an rms noise of 11 uJy/beam. In this paper, we present the source catalogue (~6000 sources with flux densities S>55 uJy (5sigma), and we discuss the 1.4 GHz source counts derived from it. Our source counts provide very robust statistics in the flux range 0.1<S<1 mJy, and are in excellent agreement with other robust determinations obtained at lower and higher flux densities. A clear excess is found with respect to the counts predicted by the semi-empirical radio sky simulations developed in the framework of the Square Kilometre Array Simulated Skies project. A preliminary analysis of the identified (and classified) sources suggests this excess is to be ascribed to star-forming galaxies, which seem to show a steeper evolution than predicted.Comment: accepted for publication on MNRAS. New version that corrects latex errors and contain the correct version of figure 1

An Evidence-Based Survey on Full-Scale Membrane Biological Reactors: Main Technical Features and Operational Aspects

This paper presents the results of a survey on full-scale membrane biological reactors (MBRs) wastewater treatment plants (WWTPs) in Italy. Alongside the main technical characteristics of the Italian MBR plants, the opinions of the plant managers on the operational advantages and disadvantages are described. As reported by the MBR technology suppliers, approximately 290 MBR municipal or industrial WWTPs are in operation in Italy, out of which 242 were studied in this survey. Data from more than one hundred municipal WWTPs were collected; these account for a total capacity of about 2,000,000 population equivalent (PE), which corresponds to 3% of the total organic load treated by the Italian WWTPs with secondary and advanced treatment. Usually, small installations adopt the flat-sheet rather than hollow-fiber membrane configuration. The main reasons why the MBR technology has been preferred to other options are its potential to be used for increasing the treatment capacity of existing plants and its compactness. Moreover, the followed operational advantages have been highlighted: easiness to comply with the discharge limits, removal of pathogens without specific disinfection units, possibility of internal reuse of the effluent, and process automation. Membrane fouling and plant shutdown have been recorded as the most relevant troubles, the last one indeed occurring only occasionally or rarely