Assessing and Adjusting Bias Due to Mixed-Mode in Aspect of Daily Life Survey

Abstract The mixed-mode (MM) designs are adopted by NSIs both to contrast declining response and coverage rates and to reduce the cost of the surveys. However, MM introduces several issues that must be addressed both at the design phase, by defining the best collection instruments to contain the measurement error, and at the estimation phase, by assessing and adjusting the mode effect. In the MM surveys, the mode effect refers to the introduction of bias effects on the estimate of the parameters of interest due to the difference in the selection and measurement errors specific to each mode. The switching of a survey from single to mixed-mode is a delicate operation: the accuracy of the estimates must be ensured in order to preserve their consistency and comparability over time. This work focuses on the methods chosen for the evaluation of the mode effect in the Italian National Institute of Statistics (ISTAT) mixed-mode survey "Aspects of Daily Life – 2017", in the experimental context for which an independent control single-mode (SM) PAPI sample was planned to assess the introduction of the sequential web/PAPI survey. The presented methods aim to analyze the causes that can determine significant differences in the estimates obtained with the SM and MM surveys

Ocrelizumab reduces cortical and deep grey matter loss compared to the S1P-receptor modulator in multiple sclerosis

Introduction: Ocrelizumab (OCR) and Fingolimod (FGL) are two high-efficacy treatments in multiple sclerosis which, besides their strong anti-inflammatory activity, may limit neurodegeneration. Aim: To compare the effect of OCR and FGL on clinical and MRI endpoints. Methods: 95 relapsing-remitting patients (57 OCR, 38 FGL) clinically followed for 36 months underwent a 3-Tesla MRI at baseline and after 24 months. The annualized relapse rate, EDSS, new cortical/white matter lesions and regional cortical and deep grey matter volume loss were evaluated. Results: OCR reduced the relapse rate from 0.48 to 0.04, FGL from 0.32 to 0.05 (both p < 0.001). Compared to FGL, OCR-group experienced fewer new white matter lesions (12% vs 32%, p = 0.005), no differences in new cortical lesions, lower deep grey matter volume loss (- 0.12% vs - 0.66%; p = 0.002, Cohen's d = 0.54), lower global cortical thickness change (- 0.45% vs - 0.70%; p = 0.036; d = 0.42) and reduced cortical thinning/volume loss in several regions of interests, including those of parietal gyrus (d-range = 0.65-0.71), frontal gyrus (d-range = 0.47-0.60), cingulate (d-range = 0.41-0.72), insula (d = 0.36), cerebellum (cortex d = 0.72, white matter d = 0.44), putamen (d = 0.35) and thalamus (d = 0.31). The effect on some regional thickness changes was confirmed in patients without focal lesions. Conclusions: When compared with FGL, patients receiving OCR showed greater suppression of focal MRI lesions accumulation and lower cortical and deep grey matter volume loss

Metodi per il trattamento delle diverse componenti della mancata risposta totale applicati all’indagine Istat sulla Disabilità

The negative effects of non-response on the estimates of a sample survey must be properly treated. The methods, generally used for this purpose, are based on the use of auxiliary information known both for respondent and not respondent units, without taking into account the causes of the non-response. In this paper, methods, which consider this aspect, have been tested for the treatment of non-response in the Istat survey on Disabilities. The methods applied are the sequential weight adjustment method and the method based on a sample selection model with multiple selection equations; the first was adopted to correct the sample weights of the respondent units to the survey, the second to verify the assumptions which underlie of the first method and to analyze the impact of the bias effects produced by different causes of non-response on some survey estimates

A feasibility study for CO2 geological storage in Northern Italy

The research concerns the assessment of the possibility to design a CCS pilot project in a deep saline aquifer of Northern Italy (Lombardia Region), one of the most populated and industrialized area of the Country. Lombardia Region emits about 70 Mt CO2 per year, ranking the Region as the largest Italian producer. The study area covers an area of about 1500 km2, and the potential caprock-reservoir system has been identified in a clay and conglomerate formation, respectively. A 3D static geological model and a 3D fluid-dynamic model have been implemented in order to analyze the CO2 storage process. After the evaluation of the storage capacity of the geological system identified in the study area, six different injection scenarios have been simulated, by considering 30 years of fluid injection at a rate of 0.3 Mt of CO2 per year. For a preliminary assessment of safety conditions, CO2 plume size, volume and displacement, together with overpressures distribution at the caprock-reservoir boundary have been simulated and analyzed. This study represent a first step for the evaluation of the storage capacity of the study area, and the results of the numerical simulations seems to confirm the possibility to develop a CCS pilot project in the future. The numerical simulations confirm, amongst the other, that the geological system is compatible with the storage of a mass of CO2 consistent with the design of a pilot project. However, further analyses are necessary (such as detailed site-investigations to confirm some geological assumptions and exhaustive geomechanical studies) before considering this area fully suitable for CCS

Making Visible the Invisible: Automatically Measured Global and Regional Brain Volume Is Associated with Cognitive Impairment and Fatigue in Multiple Sclerosis

In multiple sclerosis (MS), the transition from relapsing-remitting to the secondary-progressive phase is characterized by a progression independent of relapse activity (PIRA), resulting in physical disability accumulation and invisible symptoms, i.e., fatigue and cognitive impairment (CI). These symptoms are related to neurodegenerative processes and have been correlated with MRI measures of brain atrophy only at a group level; however, the application in clinical practice of atrophy-based measurements for single-patient evaluation is yet to be fully investigated. In the present study, we aimed to evaluate the association between brain atrophy, measured with easy-to-use automatic software, and the “invisible” MS symptoms of cognition and fatigue. A total of 69 MS patients were included in the study; cognitive impairment and fatigue (FSS) (in addition to neurological disability, EDSS) were assessed and correlated with brain volumes calculated using the automated software QyScore® which is validated for single-patient use in the clinical setting. Results showed that the cognitive status was accurately reflected by measures of atrophy, with a sensitivity of up to 90%. CI patients showed a lower volume compared to cognitively normal patients in the whole brain (p = 0.017), gray matter (p = 0.042), insula (p = 0.035), cerebellum (p = 0.008), and limbic lobe (p = 0.049). FSS was associated with temporal lobe (r = −0.37, p = 0.013) and insular (r = −0.36, p = 0.019) volumes. The volumes of the same regions were also associated with EDSS. The global/regional atrophy results, assessed with automatic and easy-to-use software, correlated with cognitive and fatigue symptoms, thus supporting the clinical application in routine patient management

Geoarchaelogical documentation of a series of destructive events at Montegibbio Roman villa site

The Italian territory is rich in archaeological heritage, located in hilly, plain or coastal areas. Frequently, it is possible to \ufb01nd only the remains of ancient cultures, villages and sparse houses dating back many centuries. Therefore, no other documentation but the remains themselves can give information about both the existence and the events that eventually determined the end of historical sites, caused either by abandonment or destruction. The causes that can determine the abandonment or the destruction can be various, and may be due to anthropic and/or natural causes, and only in very few cases documents or pictures of these events are preserved. Anthropic causes can be diverse: wrong design and/or building schemes of the structure or of the foundation, wars etc. Natural causes could be variuos as well, and can be related to the environmental context of the site. For example, in mountainous areas the main causes can be landslides, snow avalanches, soil creep affecting the foundations. In plain areas \ufb02oods are the main process leading to the disruption of hamlets. Along the coast tsunamis are to be considered. Other natural causes could be earthquakes or climate changes. In the Emilian Apennines, near Sassuolo (Modena, Italy), a Roman villa dated from the I century B.C. to the VI century A.D. has been excavated along a gentle slope. The villa can be divided in four different buildings from successive periods. During the \ufb01rst period of life of the villa (I century B.C.-I century A.D.) a destructive event caused the abandonment of this building, whose walls and mosaic \ufb02oors have been destroyed in a odd way. Which was the cause of this destruction? An earthquake, a human error in construction or a landslide? What makes this question even more interesting is the probable relation of this event with an ancient source (Pliny the Older, Naturalis Historia II, 199) who remembers how in the Modena area a \u201cportentum terrarum\u201d (earthquake) and the collision of two mountains destroyed buildings and properties. Historically, the Sassuolo hills are identi\ufb01ed as the location of this event, where similar destructive events have been attested also later on, also in correlation with the presence of mud volcanoes nearby the area. The research is aimed at de\ufb01ning the causes that determined the destruction of the Roman villa located along the Montegibbio slope. The study was carried out with a multidisciplinary approach, integrating several experts, including archaeologists, geologists and engineers. At present, no document or picture referring the causes of the destruction have been found. Therefore, in order to draw some hypotheses on the nature of the events, the analysis of the deformation of the remains, of the foundation of the buildings and the reconstruction of the slope evolution have been carried out. The results obtained so far highlight the fact that integration of geological records and archaeological evidence is the key point to unravel the evolution of this historical site

Evidence of late-Holocene mud-volcanic eruptions in the Modena foothills (northern Italy)

Among natural hazards, mud volcanoes can damage property and infrastructures and affect hillslope evolution at different spatial and temporal scales. The results of 10-year-long multidisciplinary investigations performed on a Roman-age archaeological site, La Rovina di Montegibbio, are presented, showing a peculiar example of mutual interplay between human settlement and geological forcing in the mud-volcanic environment. The site (350 m a.s.l.) lies at the termination of the upper Secchia River catchment, near the town of Sassuolo (Modena Province). Here, a 4-km-long mud volcano belt borders the Apennines chain front, comprising one of the most prominent mud volcanoes of Italy (Salsa di Montegibbio), and the still-active chain hinge tectonics gives origin to gas and oil seeps. Based on geological, geoarchaeological, palaeobotanical, geochemical, geophysical records and analytical data, we unravel the onset, the evolution and the abandonment of the settlement in relation to the existence of a previously unknown mud volcano, belonging to the larger Montegibbio mud volcano system. The damages affecting the Roman-age buildings record the ground deformations in the context of mud volcano tectonics. In particular, the pattern of faults set buried under the archaeological site is shown and compared with that of the main mud volcano conduit. At least two Roman-age eruptive episodes have been recorded, whose ejected muds are geochemically characterized. The first recorded eruption must be regarded as the reason for the initial location and function of the sacred ancient settlement. The final site abandonment was because of subsequent severe ground deformations affecting the hillslope as a consequence of mud volcano activity

The CSF profile linked to cortical damage predicts Multiple Sclerosis activity

OBJECTIVE: Intrathecal inflammation correlates with the grey matter damage since the early stages of Multiple Sclerosis (MS), but whether the cerebrospinal fluid (CSF) profile can help to identify patients at risk of disease activity is still unclear. METHODS: We evaluated the association between CSF levels of 18 cytokines, previously found to be associated to grey matter damage, and the disease activity, among 99 relapsing-remitting MS patients, who underwent blinded clinical and 3T-MRI evaluations for 4\u2009years. Groups with (EDA) or without (NEDA) evidence of disease activity (occurrence of relapses, new white matter lesions, EDSS change) were identified. Cortical lesions and the annualized cortical thinning were also evaluated. RESULTS: Fortyone patients experienced EDA and, compared to the NEDA group, had at diagnosis higher CSF levels of CXCL13, CXCL12, IFN\u3b3, TNF, sCD163, LIGHT and APRIL (p<0.001). In the multivariate analysis, CXCL13 (HR=1.35, p=0.0002), LIGHT (HR=1.22, p=0.005) and APRIL (HR=1.78, p=0.0001) were the CSF molecules more strongly associated with the risk of EDA. The model including CSF variables predicted more accurately the occurrence of disease activity than the model with only clinical/MRI parameters (C-index at 4\u2009years=\u200971% vs 44%). Finally, higher CSF levels of CXCL13 (\u3b2=4.7*10-4 ,p<0.001), TNF (\u3b2=3.1*10-3 ,p=0.004), LIGHT (\u3b2=2.6*10-4 ,p=0.003), sCD163 (\u3b2=4.3*10-3 ,p=0.009) and TWEAK (\u3b2=3.4*10-3 ,p=0.024) were associated with more severe cortical thinning. INTERPRETATION: A specific CSF profile, mainly characterized by elevated levels of B-cell related cytokines, distinguishes patients at high risk of disease activity and severe cortical damage. The CSF analysis may allow stratifications of patients at diagnosis for optimizing therapeutic approaches. This article is protected by copyright. All rights reserved