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In the inversion of geophysical data, an attempt is made to obtain a model with the best fit on the observed data. Unfortunately, the results are usually accompanied by non-uniqueness and ambiguity. These inversion problems can be reduced by inverting different geophysical datasets. Sequential inversion is one of the most common ways to integrate two or more geophysical datasets, to obtain a model that is compatible with all geophysical data, thus reducing the amount of ambiguity. This paper presents separate inversions of DC resistivity and magnetic data and sequential inversion of DC resistivity constrained by magnetic data. Here, the inverse model of magnetic data is considered the initial model for the sequential inversion of DC resistivity data. At first, the algorithm is applied to a synthetic model composed of four conductive and magnetized bodies, and the results show notable improvement for the resistivity model after sequential inversion, compared with the separate resistivity inversion model. Finally, encouraged by the results obtained in the synthetic case, the algorithm was applied to DC resistivity and magnetic datasets that were collected in the archeological area of old Pompeii city nearby Naples, Italy. The result of the sequential resistivity inversion model was notably superior to the corresponding resistivity model obtained from standard separate inversion.

Filtering is a fundamental procedure that precedes further quantitative interpretations. In the potential fields case, filtering is used to separate and discriminate the different contributions of a given dataset. In this note we describe a potential field filtering technique based on a “Extremely Compact Sources” (ECS) approach. ECS filtering method allows us to solve the problem of the interfering anomalies, that could hide the real amplitude and shape of the single contributions. The interference phenomena may involve the superimposition of a regional field generated by deep sources in the study area on local anomalies, or the superimposition of anomalies having similar wavelengths. While many methods have been developed during the years to try to separate regional from local fields, fewer methods have been developed to address the separation of interfering anomalies caused by similar sources. The ECS technique exploits the inherent ambiguity of potential fields to retrieve an extremely compact source model in which sources are well separated each one from other. In this way, the filtering process can be done through a simple "muting" process (setting the physical property of the cells relative to the unwanted contributions to 0) directly in the source domain. We show applications of the ECS technique to both synthetic and real anomalies to prove the validity of the methodology for both separation of interfering anomalies and filtering of regional fields.

This paper reviews different approaches to the problem of finding the shape of the basement buried under sedimentary basins from gravity data and explores the applicability of a recently proposed method to a well-constrained real case, comparing the results obtained with the models computed using a variety of techniques. Many gravity inversion techniques to estimate the depth to basement based on rather different approaches have been proposed. As is well known, the interpretation of gravity data requires certain assumptions about the source, aimed at constraining the solution of an ambiguous problem. The different approaches imply different kinds of solutions, namely a density contrast distribution at depth, or a grid defining the depth to basement in the entire area of study or several single depth estimates. Each approach has its own advantages and weaknesses. In this context, special attention is given to the ITerative RESCaling method (ITRESC), which has been recently proposed. In this method, there is no need to assume a density function, which is estimated by a data-driven procedure and then used to generate a grid of the depth to basement. This technique is based on the depth–gravity relation plot, illustrating the link between the depth to basement, known at some control points (e.g., boreholes or interpretation of other geophysical data), and the values of the residual gravity anomaly. An important feature of the ITRESC method is that borehole control points are used globally rather than locally, providing constraints for all parts of the model. The main features of this innovative method are illustrated and evaluated by its application to the gravity anomalies of the Yucca Flat basin (Nevada). The results are compared with models obtained by previous gravity interpretations and by the processing of other geological and geophysical data.

Recent techniques of three-dimensional (3D) imaging of potential field anomalies are effective in estimating the source position in the subsurface by exploiting both the differentiation of the field and the stability of the method. Such a processing is fast and especially suitable for detecting isolated and compact sources, as usually are those of archaeological interest. Among these methods we employed techniques that take advantage from innovative concepts like the multiscale transformation and the scaling function, going well beyond the standard procedures usually employed for data processing with archaeological purposes. We interpreted magnetic data acquired during two geophysical surveys carried out in 2008 and 2010 at Tell Barri, in north-eastern Syria. Tell Barri is a relevant site for the history of North Mesopotamia. The earliest settlement dates back to the end of the fourth millennium bce whereas the site has been occupied - with no major breaks - until the fourteenth century ce. Based on the magnetic data interpretation, we have selected a test area as a target for an archeological excavation. The excavation found ancient structures closely matching the magnetic source revealed by the geophysical imaging. Since both the ground soil and the material of buried archaeological structures are representative of several ancient settlements in a much larger area (Upper Mesopotamia), we believe that such a geophysical approach could be successful in many archaeological sites scattered through this broad region.

Ground-shaking phenomena in intermontane basins emplaced in seismically active areas are strongly affected by sediment thickness. There, the development of human settlements, encouraged because of the flat topography in a mostly mountainous region, implies demographic growth and an increased seismic risk, as recent earthquakes in Central Italy confirmed. The knowledge of the thickness of the basin infills and of their density distribution is critical for the ground-motion amplification analysis. We apply the recently proposed ITerative RESCaling (ITRESC) method for 3D gravity modelling to the Middle Aterno Valley (Apennines, central Italy), a fault-controlled basin where a strong seismic activity recently occurred. Although the structural framework was previously investigated through 1D or 2D geophysical studies, here for the first time a full 3D model of the carbonate basement morphology is computed by the inversion of gravity data. Differently from usual gravity modelling approaches, the ITRESC technique 1) does not assume a density contrast function, which is instead determined through a data-driven process, and 2) integrates geological or geophysical constraints to define a global “gravity/depth-to-basement” rescaling law, valid in all the investigated area. Our model integrates a number of depth constraints of different nature while at the same time honoring the gravity anomalies. The obtained gravity model of the basement depth shows several analogies with previous studies, although with significant, localized discrepancies. The results of this study are only partially consistent with a structural evolution of the Middle Aterno Valley through a polyphasic sequence, as previously hypothesized.

SUMMARY We define a two-step procedure to obtain reliable inverse models of the distribution of electrical conductivity at depth from apparent conductivities estimated by electromagnetic instruments such as GEONICS EM38, EM31 or EM 34-3. The first step of our procedure consists in the correction of the apparent conductivities to make them consistent with a low induction number condition, for which these data are very similar to the true conductivity. Then, we use a linear inversion approach to obtain a conductivity model. To improve the conductivity estimation at depth we introduced a depth-weighting function in our regularized weighted minimum length solution algorithm. We test the whole procedure on two synthetic data sets generated by the COMSOL Multiphysics for both the vertical magnetic dipole and horizontal magnetic dipole configurations of the loops. Our technique was also tested on a real data set, and the inversion result has been compared with the one obtained using the dipole-dipole DC electrical resistivity (ER) method. Our model not only reproduces all shallow conductive areas similar to the ER model, but also succeeds in replicating its deeper conductivity structures. On the contrary, inversion of uncorrected data provides a biased model underestimating the true conductivity.

The compensation of magnetic and electromagnetic interference generated by drones is one of the main problems related to drone-borne magnetometry. The simplest solution is to suspend the magnetometer at a certain distance from the drone. However, this choice may compromise the flight stability or introduce periodic data variations generated by the oscillations of the magnetometer. We studied this problem by conducting two drone-borne magnetic surveys using a prototype system based on a cesium-vapor magnetometer with a 1000 Hz sampling frequency. First, the magnetometer was fixed to the drone landing-sled (at 0.5 m from the rotors), and then it was suspended 3 m below the drone. These two configurations illustrate endmembers of the possible solutions, favoring the stability of the system during flight or the minimization of the mobile platform noise. Drone-generated noise was filtered according to a CWT analysis, and both the spectral characteristics and the modelled source parameters resulted analogously to that of a ground magnetic dataset in the same area, which were here taken as a control dataset. This study demonstrates that careful processing can return high quality drone-borne data using both flight configurations. The optimal flight solution can be chosen depending on the survey target and flight conditions.

Sediments infilling in intermontane basins in areas with high seismic activity can strongly affect ground-shaking phenomena at the surface. Estimates of thickness and density distribution within these basin infills are crucial for ground motion amplification analysis, especially where demographic growth in human settlements has implied increasing seismic risk. We employed a 3D gravity modeling technique (ITerative RESCaling—ITRESC) to investigate the Fucino Basin (Apennines, central Italy), a half-graben basin in which intense seismic activity has recently occurred. For the first time in this region, a 3D model of the Meso-Cenozoic carbonate basement morphology was retrieved through the inversion of gravity data. Taking advantage of the ITRESC technique, (1) we were able to (1) perform an integration of geophysical and geological data constraints and (2) determine a density contrast function through a data-driven process. Thus, we avoided assuming a priori information. Finally, we provided a model that honored the gravity anomalies field by integrating many different kinds of depth constraints. Our results confirmed evidence from previous studies concerning the overall shape of the basin, however, we also highlighted several local discrepancies, such as: (a) the position of several fault lines, (b) the position of the main depocenter, and (c) the isopach map. We also pointed out the existence of a new, unknown fault, and of new features concerning known faults. All of these elements provided useful contributions to the study of the tectono-sedimentary evolution of the basin, as well as key information for assessing the local site-response effects, in terms of seismic hazards.

The pandemic COVID-19 abruptly exploded, taking most health professionals around the world unprepared. Italy, the first European country to be hit violently, was forced to activate the lockdown in mid-February 2020. At the time of the spread, a high number of victims were quickly registered, especially in the regions of Northern Italy which have a high rate of highly-polluting production activities. The need to hospitalize the large number of patients with severe forms of COVID-19 led the National Health System to move a large number of specialists from their disciplines to the emergency hospital departments for the treatment of COVID-19. Furthermore, the lockdown itself has limited the possibility for general practitioners and pediatricians to be able to make outpatient visits and/or home care for patients with chronic diseases. Among them, the patient with atopic diseases, such as asthma, rhinitis and atopic dermatitis, is worthy of particular attention as she/he is immersed in a studded negative scenario with the onset of spring, a factor that should not be underestimated for those who suffer from pollen allergy. The Italian Society of Asthma Allergology and Clinical Immunology, to quickly deal with the lack of references and specialist medical procedures, has produced a series of indications for immunologic patient care that are reported in this paper, and can be used as guidelines by specialists of our discipline.

Background: Epidemiological studies show that BCG vaccinated population seems to be more likely protected from COVID-19 infection, but WHO gave a stark warning on use of BCG vaccine without confirmed COVID-19 trials. The aim of this survey is to assess the ability and readiness to respond to viral infection by physicians who had been BCG vaccinated. Methods: After Ethical Committee authorization, professional orders were used to contact physicians with an online survey. Specialty, COVID-19 infection, and previous BCG vaccination were recorded. Statistical data analysis was performed. Results: 1906 medicals answered the questionnaire, (M=1068; F=838; mean age 50.7+/-13.3; >24

Background Epidemiological studies have shown an association between global warming, air pollution, and allergic diseases. Several air pollutants, including volatile organic compounds, formaldehyde, toluene, nitrogen dioxide (NO2 ), and particulate matter, act as risk factors for the development or aggravation of atopic dermatitis (AD). We evaluated the impact of air pollutants and weather changes on AD patients. Materials and methods Sixty AD patients ≥5 years of age (mean age: 23.5 ± 12.5 years), living in the Campania Region (Southern Italy), were followed for 18 months. The primary outcome was the effect of atmospheric and climatic factors on signs and symptoms of AD, assessed using the SCORAD (SCORing Atopic Dermatitis) index. We measured mean daily temperature (TOD), outdoor relative humidity (RH), diurnal temperature range (DTR), precipitation, particulate with aerodynamic diameter ≤ 10 μm (PM10 ), NO2 , tropospheric ozone (O3 ), and total pollen count (TPC). A multivariate logistic regression analysis was used to examine the associations of AD signs and symptoms with these factors. An artificial neural network (ANN) analysis investigated the relationships between weather changes, environmental pollutants, and AD severity. Results The severity of AD symptoms was positively correlated with outdoor temperatures (TOD, DTR), RH, precipitation, PM10 , NO2 , O3 , and TPC. The ANN analysis also showed a good discrimination performance (75.46%) in predicting disease severity based on environmental pollution data, but weather-related factors were less predictive. Conclusion The results of the present study provide evidence that weather changes and air pollutions have a significant impact on skin reactivity and symptoms in AD patients, increasing the severity of the dermatitis. The knowledge of the single variables proportion on AD severity symptoms is important to propose alerts for exacerbations in patients with AD of each age. This finding represents a good starting point for further future research in an area of increasingly growing interest.

The Central and Southern Apennines are characterized by the occurrence of intense and widely spread historical and recent seismic activity, mostly located along the chain.In this paper, we present a multi-parametric data analysis in GIS environment (Geographic Information System) with the aim of identifying and constraining the geometry (strike, dip direction and dip angle) of the seismogenic faults in areas of Central-Southern Apennines characterized by outcropping/ buried and/or active/silent faults.We use an integrated analysis of geo-structural, seismological and gravimetric data, for the identification and geometrical description of faults with density contrast, both at the surface and at depth. At the surface, the gravity lineaments inferred by Multiscale Derivative Analysis (MDA) were compared with the Quaternary faults mapped in the study areas and with the earthquakes’ epicentral distribution. The characterization of faults at depth was instead performed by the combination of the Depth from Extreme Points (DEXP) gravity imaging method with hypocentral sections.We tested the effectiveness of this multi-method approach at Mt. Vettore-Mt. Bove, L’Aquila basin, Mt. Massico and San Giuliano di Puglia areas (Central and Southern Apennines).Given the effectiveness of the obtained results, this multiparametric study has been applied to other three areas of the Abruzzo-Molise region: the south-western sector of Mt. Matese, the Fucino basin and the Sulmona basin.The Matese area was hit by a seismic sequence in 2013-2014 (Mwmax= 5.1 on December 29, 2013). Our approach showed a correlation between the epicentral distribution of the 2013-2014 Matese seismic sequence (Mw=5.0) and the MDA lineaments from gravity data. The hypocentral distibution suggests that the fault rupture does not reach the surface. Therefore, the seismogenic fault responsible of 2013-2014 Matese seismic sequence is likely a buried fault.The Fucino basin was struck by a Mw=7.0 earthquake on January 13, 1915, causing 30,000 causalities within a large area surrounding the basin. At present, the area is characterized by scarce instrumental seismicity with low magnitude. Our analysis highlights a good correlation between NW-SE and NE-SW well-known faults and clear gravimetric MDA maxima bordering the plain. This area can be currently considered silent but, from historical seismological studies, it is one the highest seismic risk areas of Central Apennines.Moreover, we investigated the area of the Sulmona basin, the southwards extension of the eastern system of Central Apennines developing from Mt. Vettore, Mt. Gorzano and Mt. Gran Sasso. In historical times, the faults of the most external extensional alignment, defined as silent and considered as probable seismic gaps, activated during the 2016 Amatrice–Visso–Norcia seismic sequence. Further to the southeast, two relatively large earthquakes occurred on the eastern flank of Mt. Maiella on November 3, 1706 (Mw=6.6) and on September 26, 1933 (Mw=5.7). The Sulmona area is presently characterized by poor and low magnitude instrumental seismicity. Our multi-parametric analysis highlighted a strong correlation between MDA maxima and the Mt. Morrone normal fault bordering the western side of Mt. Maiella and the eastern side of the Sulmona basin.

We analyze a wide gravity low in the Campania Active Volcanic Area and interpret it by a large and deep source distribution of partially molten, low-density material from about 8 to 30 km depth. Given the complex spatial-temporal distribution of explosive volcanism in the area, we model the gravity data consistently with several volcanological and petrological constraints. We propose two possible models: one accounts for the coexistence, within the lower/intermediate crust, of large amounts of melts and cumulates besides country rocks. It implies a layered distribution of densities and, thus, a variation with depth of percentages of silicate liquids, cumulates and country rocks. The other reflects a fractal density distribution, based on the scaling exponent estimated from the gravity data. According to this model, the gravity low would be related to a distribution of melt pockets within solid rocks. Both density distributions account for the available volcanological and seismic constraints and can be considered as end-members of possible models compatible with gravity data. Such results agree with the general views about the roots of large areas of ignimbritic volcanism worldwide. Given the prolonged history of magmatism in the Campania area since Pliocene times, we interpret the detected low-density body as a developing batholith.

The normalized full gradient is based on the noticeable stability of the modulus of the analytic signal of downward potential fields. We have developed a new approach to the study of the normalized full gradient, based on assessing the entropy of the normalized modulus of the analytic signal at each level of continuation. The increased disorder of progressively downward continued fields implies an increase of the computed entropy. However, a local decrease of the entropy is expected at the source level, where the field gets singular, as entropy decreases when the information is concentrated. Thus, our method is based on a simple search for a minimum of the computed entropy versus depth curve, and the estimated depth will be that at which the minimum is attained. The method is sensitive to interference and other types of noise, and specific strategies to deal with these limitations are defined and tested on synthetic data. The depth estimate is obtained without the assumption of a specific source shape. The depth could correspond to the top or center in case of a simple, one-point source, or it may be related to an intermediate depth between the source top and its center in case of a finite, general source. We applied this method to real magnetic data from an unexploded ordnance survey, and it could verify a rather accurate depth-to-source estimate when compared with excavation results.

We have developed a method to interpret potential fields, which obtains 1D models by inverting vertical soundings of potential field data. The vertical soundings are built through upward continuation of potential field data, measured on either a profile or a surface. The method assumes a forward problem consisting of a volume partitioned in layers, each of them homogeneous and horizontally finite, but with the density changing versus depth. The continuation errors, increasing with the altitude, are automatically handled by determining the coefficients of a third-order polynomial function of the altitude. Due to the finite size of the source volume, we need a priori information about the total horizontal extent of the volume, which is estimated by boundary analysis and optimized by a Markov chain process. For each sounding, a 1D inverse problem is independently solved by a nonnegative least-squares algorithm. Merging of the several inverted models finally yields approximate 2D or 3D models that are, however, shown to generate a good fit to the measured data. The method is applied to synthetic models, producing good results for either perfect or continued data. Even for real data, i.e., the gravity data of a sedimentary basin in Nevada, the results are interesting, and they are consistent with previous interpretation, based on 3D gravity inversion constrained by two gamma-gamma density logs.

In this paper, we present a new Bouguer gravity map of the Northern Tuscan offshore (central Italy), based on original gravity data acquired on the islands of the Tuscan Archipelago. Our dataset integrates 274 unpublished gravity field measurements with 126 available marine gravity data of the northern Tyrrhenian Sea. The Bouguer anomaly map shows a westward and southward increase of the regional gravity field associated with the uplift of the Moho boundary from central Apennines towards the Tyrrhenian Sea. At a local scale, several Bouguer anomalies are well associated with the igneous plutons of the Elba, Montecristo and Capraia islands, as a result of a deep density contrast between the granitoid intrusive rocks and the embedding metamorphic basement. The presented Bouguer anomaly map represents a useful tool for future studies of the complex geological and geodynamical setting of the Tuscan Archipelago and of the buried and deep igneous structures.

The Yucca Flat is located in the Basin and Range province and it was one of four major nuclear test regions of the Nevada National Security Site. In the past decades, many gravity stations were acquired in this site, along with an unusually high number of boreholes. This dataset is here modelled by the ITRESC method, based on the building of a depth-gravity relationship, for which a set of depth constraints (i.e., estimates of the depth to basement at some locations) are needed. The main difference between this method and most of the approaches commonly used to model the basement morphology is that the density function is not required as an input, but it is instead a product of the interpretation process. The resulting model displays many details more than previous interpretations. The maximum thickness of sediments is found to be about 1.2 km. Information about the presence of horizontal density contrasts in the sediment filling, a complexity that the method cannot take into account, can be obtained from the misfit between the basement model and the borehole depths to basement.

Background: Understanding the level of patients’ satisfaction with treatment and its determinants have the potential to impact therapeutic management and clinical outcome in chronic conditions such as chronic obstructive pulmonary disease (COPD). Methods: A national, multicenter, longitudinal, observational study of COPD from 20 Italian pulmonary centers to explore patients’ satisfaction to treatment [assessed by the Treatment Satisfaction Questionnaire, 9 items (TSQM-9)] and association with clinical parameters [including dyspnea score, COPD Assessment Test (CAT) score, exacerbation rate], adherence to treatment [Morisky Medication-Taking Adherence Scale (MMAS-4)], illness perception [evaluated by Brief Illness Perception Questionnaire (B-IPQ)] in a 1-year follow up. Results: A total of 401 COPD patients were enrolled [69.4% group B Global Initiative for COPD (GOLD), considering 366 patients with available GOLD 2017 classification at enrollment]. At enrollment, satisfaction with treatment was moderate, being TSQM-9 mean scores for effectiveness 64.2 [95% confidence interval (CI) 62.5–65.9], for convenience 75.8 (95% CI 74.2–77.3), and for global satisfaction 65.7 (95% CI 64.0–67.4). Global satisfaction was negatively associated with disease perception (β = −0.4709, p Conclusions: The results of this real-life study showed that the patients’ satisfaction with treatments is only moderate in COPD. A high grade of patients’ satisfaction is associated mainly with a low perception of the disease, high adherence to treatment and lower level of dyspnea. Trial Registration: Clinicaltrials.gov identifier: NCT02689492 The reviews of this paper are available via the supplemental material section.

The gravity gradient tensor (GGT) has been increasingly used in practical applications, but the advantages and the disadvantages of the analysis of GGT components versus the analysis of the vertical component of the gravity field are still debated. We analyse the performance of joint inversion of GGT components versus separate inversion of the gravity field alone, or of one tensor component. We perform our analysis by inspection of the Picard Plot, a Singular Value Decomposition tool, and analyse both synthetic data and gradiometer measurements carried out at the Vredefort structure, South Africa.We show that the main factors controlling the reliability of the inversion are algebraic ambiguity (the difference between the number of unknowns and the number of available data points) and signal-to-noise ratio. Provided that algebraic ambiguity is kept low and the noise level is small enough so that a sufficient number of SVD components can be included in the regularized solution, we find that: (i) the choice of tensor components involved in the inversion is not crucial to the overall reliability of the reconstructions; (ii) GGT inversion can yield the same resolution as inversion with a denser distribution of gravity data points, but with the advantage of using fewer measurement stations.

A microgravity survey was completed to precisely locate and better characterize the near-surface geometry of a recent fault with small throw in a mountainous area in the Southern Apennines (Italy). The site is on a segment of the Irpinia fault, which is the source of the M6.9 1980 earthquake. This fault cuts a few meter of Mesozoic carbonate bedrock and its younger, mostly Holocene continental deposits cover. The amplitude of the complete Bouguer anomaly along two profiles across the fault is about 50 μGal. The data were analyzed and interpreted according to a self-constrained strategy, where some rapid estimation of source parameters was later used as constraint for the inversion. The fault has been clearly identified and localized in its horizontal position and depth. Interesting features in the overburden have been identified and their interpretation has allowed us to estimate the fault slip-rate, which is consistent with independent geological estimates.

A simple relation exists between the depth to basement and gravity or pseudo-gravity fields. Based on this relation, a method to recover the density (or magnetization) contrast function and the basement morphology under sedimentary basins is developed. Use of this method is possible when several depth constraints are available, as given by boreholes perforating the basement or other geophysical data interpretations indicating the depth to basement at some locations. A nice feature of the method is its computational efficiency, as it involves no matrix inversion nor multiplication. The new method has been successfully applied to complex basement model and to a real data set.

I propose a new method to estimate the morphology of the basement under sedimentary basins, starting from measured gravity or magnetic anomalies. The method is based on a simple relation existing between the depth to basement and gravity or pseudogravity fields. This simple relation (approximately linear for homogeneous sediment basins) is fitted by a polynomial regression and the data can be immediately rescaled in terms of depth to the basement. The use of this method is possible when several depth constraints are available, such as wells perforating the basement or other geophysical data interpretations indicating the depth to basement at some locations. The first-approximation model is iteratively improved by rescaling the misfit between the observed and the model-generated field and by adding this correction to the first model. A further output of the method is the estimation of a constant density/magnetization contrast or of a depth-density function. The method does not consider lateral variations in the basin fill density, nor variations in the basement magnetization. The method is demonstrated on a synthetic complex basement model in the cases of a constant density contrast, with or without noise, and in the case of a variable depth-density function. The method is computationally very efficient, as it involves no matrix inversion nor multiplication. The applicability of the method to real gravity data is finally demonstrated by the modelling of the gravity anomalies of the Pannonian basin (Austria). The obtained model compares well to a previous interpretation of the same data using different constraints.

We have applied clustering techniques to the terracing of potential field data. We found out how [Formula: see text]-means clustering or a simple reclassification of the field values based on the minimum Euclidean distance from a set of cluster centers can produce a nicely terraced potential field map, with the degree of simplification of the original map controlled by the number of clusters. We developed a method to automatically define the number and the center value of these clusters. The gravity or magnetic maps terraced by clustering techniques are transformed and present no smooth transitions, and each terrace has a constant field value. Such a terraced map is thus suitable for computing an apparent physical property distribution. To obtain even better results, it is possible to combine clustering techniques with edge-preserving filters. We tested our method on simple and complex synthetic fields and finally applied it to the real gravity data of a mining region in Canada, finding good correspondence between the resulting apparent density distribution and a simplified geologic map.

We present the results of a geophysical study at the site of Pian della Tirena, near the town of Nocera Terinese (Calabria, Italy). Geophysical imaging is a recent technique providing a reliable mapping of the three-dimensional magnetization distribution below the ground and, thus, effectively estimating the depth of buried structures. The site studied gained archaeological interest following the hypothesis of the presence of two adjacent, but distinct, settlements. The first one of Hellenic/Hellenistic age (the Temesa of Brettian age), the second (called Tempsa) of Roman age. Even though the site was recently excavated, extensive investigation was not possible due to the broadness of the area and the scarceness of traces at the surface, making it difficult to plan a targeted survey. Two detailed geophysical (magnetic and electromagnetic) surveys were performed in 2006 and 2013 to provide the archaeologists with precise information about the type and position of the buried structures, and increase the efficiency of the investigation. The survey aimed to: (i) confirm and outline the existence of a true urban settlement instead of isolated dwellings; (ii) locate centres of manufacturing activities (local pottery and metal handicrafts); (iii) verify the existence of a boundary wall or road around the settlement. Our three-dimensional analysis and interpretation detected several anomaly trends, most of which show a rather regular shape and orientation. This allowed us to infer the possible existence of a well-developed urban network. The final results provided an archaeological interpretation, building upon the urban network and different use-zones within the town. Copyright © 2015 John Wiley & Sons, Ltd.

We carried out a study of the structures of the volcanic island of Ischia by the analysis and interpretation of high-resolution aeromagnetic data and by a newly compiled in-land gravity data set. The comparison between the vertical gradient of gravity data and pole-reduced magnetic data was performed through semblance analysis and highlighted a correspondence between the main magnetic and gravity highs over the lava and green tuff deposits (e.g., Punta Imperatore, Mt. Trippodi, Zaro, Mt. Rotaro, Mt. Epomeo). Our analysis also highlighted the simultaneous presence of a magnetic minimum and a gravimetric maximum in the central part of the island, mainly visible in the long-period components of the two data sets. This may be due to the existence of a partially demagnetized structure with positive density contrast, representing the island's igneous basement. The boundaries of the lava and tuffs deposits of the island were clearly pointed out by the maxima of the total horizontal gradient maps of magnetic and gravity data. Those maxima also show the position of several lineaments, in good agreement with the mapped faults of the island.

Background Asthma considerably impairs patients' quality of life and increases healthcare costs. Severity, morbidity, and degree of disease control are the major drivers of its clinical and economic impact. National scientific societies are required to monitor the application of international guidelines and to adopt strategies to improve disease control and better allocate resources. Aim to provide a detailed picture of the characteristics of asthma patients and modalities of asthma management by specialists in Italy and to develop recommendations for the daily management of asthma in a specialist setting. Method: A quantitative research program was implemented. Data were collected using an ad hoc questionnaire developed by a group of specialists selected by the Italian Pneumology Society/Italian Respiratory Society. Results The records of 557 patients were analyzed. In the next few years, specialists are expected to focus their activity patients with more severe disease and will be responsible for selection of patients for personalized biological therapy; however, only 20% of patients attending Italian specialist surgery can be considered severe. In 84.4% of cases, the visit was a follow-up visit requested in 82.2% of cases by the specialist him/herself. The Asthma Control Test is used only in 65% of patients. When available, a significant association has been observed between the test score and asthma control as judged by the physician, although concordance was only moderate (κ = 0.68). Asthma was considered uncontrolled by the specialist managing the case in 29.1% of patients; nevertheless, treatment was not stepped up in uncontrolled or partly controlled patients (modified in only 37.2% of patients). Conclusions The results of this survey support re-evaluation of asthma management by Italian specialists. More resources should be made available for the initial visit and for more severely ill patients. In addition, more extensive use should be made of validated tools, and available drugs should be used more appropriately.

In past decades, magnetic surveying had become popular as one of the most effective techniques supporting archaeological prospecting. This is possible because the existence of susceptibility contrasts between the cover soil and several buried finds often causes detectable anomalies. More recently, great advances were made in signal enhancement and boundary analysis of potential field anomalies, thanks to methods allowing a suitable differentiation of the field without making the process unstable. New three-dimensional (3D) imaging techniques provided an estimate of the magnetization distribution within the subsoil by means of high-resolution images of the source distribution. Most of these methods are fast and reliable in the presence of shallow and compact sources, just as in the case of the sources usually occurring in archaeological prospecting. Nevertheless, great effort was spent by the scientific community to overcome serious problems causing low signal-to-noise ratio in the measurements. This chapter provides a step-by-step description of technical solutions adopted to improve the quality of data and to perform a better interpretation of the magnetic anomalies usually associated to the presence of archaeological finds. To this end, a summary of case histories is illustrated giving a general framework of the latest progress in archaeo-magnetism.

The estimation of the structural index and of the depth to the source is the main task of many popular methods used to analyze potential field data, such as Euler deconvolution. However, these estimates are unstable even in the presence of a weak amount of noise, and Euler deconvolution of noisy data leads to an underestimation of structural index and depth. We have studied how the structural index and depth estimates are affected by applying low-pass filtering to the data. Physically based low-pass filters, such as upward continuation and integration, have been shown to be the best choice over a range of altitudes (upward continuation) or orders (integration filters), mainly because their outputs have a well-defined physical meaning. In contrast, mathematical low-pass filters require that the filter parameters be tuned carefully by means of several trial tests to produce optimally smoothed fields. The C-norm criterion is a reliable strategy to produce a stabilized vertical derivative, and we discourage Butterworth filters because they tend to a vertical integral filter, for a high cutoff wavenumber, thus complicating the interpretation of the estimated structural index. We found that the estimated structural index and depth to source increase proportionally with the amount of smoothing, unless in the case of overfiltering. In that case, the severe distortion of the original field may cause a decrease of the estimated structural index and depth to source.

In Cutrofiano, in the southern part of the Salento Peninsula, Apulia, Italy, a Pleistocene calcarenitic sequence was quarried by digging extensive networks of galleries along the geological succession most suitable for the quarrying activity. These caves represent a potential hazard for the built-up environment due to the occurrence of underground instability that may propagate upward and eventually reach the surface, causing sinkholes. In this work we propose integrated interdisciplinary methods for cavities detection. The methodology was applied at a test area located along a major road near Cutrofiano using geological and electrical-resistivity tomography and microgravity geophysical methods.

Potential field interpretation can be carried out using multiscale methods. This class of methods analyses a multiscale data set, which is built by upward continuation of the original data to a number of altitudes conveniently chosen. Euler deconvolution can be cast into this multiscale environment by analysing data along ridges of potential fields, e.g., at those points along lines across scales where the field or its horizontal or vertical derivative respectively is zero. Previous work has shown that Euler equations are notably simplified along any of these ridges. Since a given anomaly may generate one or more ridges we describe in this paper how Euler deconvolution may be used to jointly invert data along all of them, so performing a multiridge Euler deconvolution. The method enjoys the stable and high-resolution properties of multiscale methods, due to the composite upward continuation/vertical differentiation filter used. Such a physically-based field transformation can have a positive effect on reducing both high-wavenumber noise and interference or regional field effects. Multiridge Euler deconvolution can also be applied to the modulus of an analytic signal, gravity/magnetic gradient tensor components or Hilbert transform components. The advantages of using multiridge Euler deconvolution compared to single ridge Euler deconvolution include improved solution clustering, increased number of solutions, improvement of accuracy of the results obtainable from some types of ridges and greater ease in the selection of ridges to invert. The multiscale approach is particularly well suited to deal with non-ideal sources. In these cases, our strategy is to find the optimal combination of upward continuation altitude range and data differentiation order, such that the field could be sensed as approximately homogeneous and then characterized by a structural index close to an integer value. This allows us to estimate depths related to the top or the centre of the structure.

We present a constrained inversion procedure based on a priori information derived exclusively from the analysis on the potential field data themselves (self-constrained inversion). The procedure effectively applies to underdetermined problems and involves scenarios where the source distribution can be assumed to be of some simple character, but perturbations from this simplified body might occur. To set up effective constraints we first estimate by an analysis of the gravity or magnetic field some or all of the following source parameters: the source depth-to-the-top, the structural index, the horizontal position of the source body edges and their dip. The second step is incorporating the information related to these constraints in the objective function as depth and spatial weighting functions. We show, through some 2D and 3D synthetic and real data examples, that the sole potential field-based constraints are most of times enough to obtain rather good improvements in the density and magnetization models.

We present a new 1D inversion algorithm for potential field data, which consists in the inversion of vertical soundings of data at different altitudes. The inversion of multiple 1D vertical gravity/magnetic soundings is made over the same source-volume, which is a finite volume of layers of different densities, for interpreting anomalies along a profile or over a measurement surface. The inversion algorithm was tested on synthetic data and on a real case, relative to gravity data referred to a sedimentary basin in Nevada, USA.