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Through a small-scale interview study with Syrians with Swedish citizenship who have either relocated to, or are regularly visiting, the UK, this article sheds light on the nexus between mobility and bottom-up citizenship practices of refugees in Europe. We mobilize the twin concepts of 'affective' and 'instrumental' citizenship to highlight how refugees' quest for belonging and safety challenges usual assumptions about displacement: first, our data defy push-pull models of migration, showing that quick access to naturalization and generous welfare policies attracted some Syrians to Sweden, but were not enough to make them stay. The fact that for those leaving Sweden, the UK was only one possible destination—with other Syrians moving to the Global South—calls into question a hierarchy of desirable destinations with Western and Northern Europe at the top. Second, seen through the lens of affect, refugees' and host states' interactions are not merely legalistic or bureaucratic: while our interlocutors perceived Swedish welfare interventions and political discourse as top-down affective control, they also engaged in grassroots practices of affective citizenship, devising alternative forms of belonging through mobility. Ultimately, affective citizenship can inform ambitions to stay, or move on, regardless of how affluent host countries are. Third, while our protagonists' back-and-forth movements point to the non-linearity of refugee journeys, their use of the UK's EU Settlement Scheme as a deferred 'insurance policy' highlights the complexity of temporalities of displacement. Legal security may not be sufficient to ending refugees' lingering feelings of insecurity, and thus not preclude further mobility-based strategies. [ABSTRACT FROM AUTHOR]

The coefficient of variation is a useful indicator for comparing the spread of values between datasets with different units or widely different means. In this paper we address the problem of investigating the equality of the coefficients of variation from two independent populations. In order to do this we rely on the Bayesian Discrepancy Measure recently introduced in the literature. Computing this Bayesian measure of evidence is straightforward when the coefficient of variation is a function of a single parameter of the distribution. In contrast, it becomes difficult when it is a function of more parameters, often requiring the use of MCMC methods. We calculate the Bayesian Discrepancy Measure by considering a variety of distributions whose coefficients of variation depend on more than one parameter. We consider also applications to real data. As far as we know, some of the examined problems have not yet been covered in the literature. [ABSTRACT FROM AUTHOR]

This article looks at the existentialist nature of Ghāda al-Sammān's early short stories, with a particular focus on her very first collection, Aynāka qadarī (Your eyes are my destiny), published in 1962. Ghāda al-Sammān was born in Syria and widely celebrated for her novelistic career: this article gives centrality to two of her early short stories as they present narratives that intricately weave individual and collective struggles within the context of the Algerian war of independence. Analysing the interplay between overarching Arab causes, feminism and existential themes, this study explores the nuanced portrayal of characters grappling with the complexities of war, morality and personal redemption. The protagonists, often embodying dichotomous perspectives, symbolize dignity and barbarism, echoing existentialist principles. The article examines how al-Samman's youthful perspective and Sartrean influences shape the narratives, offering readers a unique lens into the psychological and moral dimensions of conflict. By unravelling layers of existential struggle and political engagement, this analysis sheds light on the richness and relevance of al-Samman's early works within the broader literary and philosophical landscape. [ABSTRACT FROM AUTHOR]

We study some zero-flux attraction-repulsion chemotaxis models, with nonlinear production rates for the chemorepellent and the chemoattractant, whose formulation can be schematized as (⋄) $$\begin{equation} \begin{cases} u_t= \Delta u - \chi \nabla \cdot (u \nabla v)+\xi \nabla \cdot (u \nabla w) & {\rm in}\ \Omega \times (0,T_{\max}),\\ \tau v_t=\Delta v-\varphi(t,v)+f(u) & {\rm in}\ \Omega \times (0,T_{\max}),\\ \tau w= \Delta w - \psi(t,w) + g(u) & {\rm in}\ \Omega \times (0,T_{\max}). \end{cases} \end{equation}$$ { u t = Δ u − χ ∇ ⋅ (u ∇ v) + ξ ∇ ⋅ (u ∇ w) in Ω × (0 , T max) , τ v t = Δ v − φ (t , v) + f (u) in Ω × (0 , T max) , τ w = Δ w − ψ (t , w) + g (u) in Ω × (0 , T max). In this problem, Ω is a bounded and smooth domain of $ \mathbb R^n $ R n , for $ n\geq 2 $ n ≥ 2 , $ \chi,\xi \gt 0 $ χ , ξ > 0 , $ f(u) $ f (u) , $ g(u) $ g (u) reasonably regular functions generalizing, respectively, the prototypes $ f(u)=\alpha u^k $ f (u) = α u k and $ g(u)= \gamma u^l $ g (u) = γ u l , for some $ k,l,\alpha,\gamma \gt 0 $ k , l , α , γ > 0 and all $ u\geq 0 $ u ≥ 0. Moreover, $ \varphi (t,v) $ φ (t , v) and $ \psi (t,w) $ ψ (t , w) have specific expressions, $ \tau \in \{0,1\} $ τ ∈ { 0 , 1 } and $ \Theta :=\chi \alpha -\xi \gamma $ Θ := χ α − ξ γ. Once for any sufficiently smooth $ u(x,0)=u_0(x)\geq 0 $ u (x , 0) = u 0 (x) ≥ 0 , $ \tau v(x,0)=\tau v_0(x)\geq 0 $ τ v (x , 0) = τ v 0 (x) ≥ 0 and $ \tau w(x,0)=\tau w_0(x)\geq 0, $ τ w (x , 0) = τ w 0 (x) ≥ 0 , the local well-posedness of problem ( $ \Diamond $ ◊) is ensured, and we establish for the classical solution $ (u,v,w) $ (u , v , w) defined in $ \Omega \times (0,T_{\max }) $ Ω × (0 , T max) that the life span is indeed $ T_{\max }=\infty $ T max = ∞ and u, v and w are uniformly bounded in $ \Omega \times (0,\infty) $ Ω × (0 , ∞) in the following cases: For $ \varphi (t,v)=\beta v $ φ (t , v) = β v , $ \beta \gt 0 $ β > 0 , $ \psi (t,w)=\delta w $ ψ (t , w) = δ w , $ \delta \gt 0 $ δ > 0 and $ \tau =0 $ τ = 0 , provided (I.1) k 0 , $ \psi (t,w)=\delta w $ ψ (t , w) = δ w , $ \delta \gt 0 $ δ > 0 and $ \tau =1 $ τ = 1 , whenever (II.1) $ l,k\in \left (0,\frac {1}{n}\right ] $ l , k ∈ (0 , 1 n ] ; (II.2) $ l\in \left (\frac {1}{n},\frac {1}{n}+\frac {2}{n^2+4}\right) $ l ∈ (1 n , 1 n + 2 n 2 + 4) and $ k\in \left (0,\frac {1}{n}\right ] $ k ∈ (0 , 1 n ] , or $ k\in \left (\frac {1}{n},\frac {1}{n}+\frac {2}{n^2+4}\right) $ k ∈ (1 n , 1 n + 2 n 2 + 4) and $ l\in \left (0,\frac {1}{n}\right ] $ l ∈ (0 , 1 n ] ; (II.3) $ l,k\in \left (\frac {1}{n},\frac {1}{n}+\frac {2}{n^2+4}\right) $ l , k ∈ (1 n , 1 n + 2 n 2 + 4) . For $ \varphi (t,v)=\frac {1}{|\Omega |}\int _\Omega f(u) $ φ (t , v) = 1 | Ω | ∫ Ω f (u) and $ \psi (t,w)=\frac {1}{|\Omega |}\int _\Omega g(u) $ ψ (t , w) = 1 | Ω | ∫ Ω g (u) and $ \tau =0 $ τ = 0 , under the assumptions k

This paper deals with unbounded solutions to a class of chemotaxis systems. In particular, for a rather general attraction–repulsion model, with nonlinear productions, diffusion, sensitivities, and logistic term, we detect Lebesgue spaces where given unbounded solutions also blow up in the corresponding norms of those spaces; subsequently, estimates for the blow‐up time are established. Finally, for a simplified version of the model, some blow‐up criteria are proved. More precisely, we analyze a zero‐flux chemotaxis system essentially described as ⋄ut=∇·((u+1)m1−1∇u−χu(u+1)m2−1∇v+ξu(u+1)m3−1∇w)+λu−μukinΩ×(0,Tmax),0=Δv−1|Ω|∫Ωuα+uα=Δw−1|Ω|∫Ωuβ+uβinΩ×(0,Tmax).$$\begin{equation} {\begin{cases} u_t= \nabla \cdot ((u+1)^{m_1-1}\nabla u -\chi u(u+1)^{m_2-1}\nabla v & {}\\ \qquad +\; \xi u(u+1)^{m_3-1}\nabla w) +\lambda u -\mu u^k & \text{ in } \Omega \times (0,T_{max}),\\ 0= \Delta v -\frac{1}{\vert {\Omega }\vert }\int _\Omega u^\alpha + u^\alpha = \Delta w - \frac{1}{\vert {\Omega }\vert }\int _\Omega u^\beta + u^\beta & \text{ in } \Omega \times (0,T_{max}). \end{cases}} \end{equation}$$The problem is formulated in a bounded and smooth domain Ω of Rn$\mathbb {R}^n$, with n≥1$n\ge 1$, for some m1,m2,m3∈R$m_1,m_2,m_3\in \mathbb {R}$, χ,ξ,α,β,λ,μ>0$\chi , \xi , \alpha ,\beta , \lambda ,\mu >0$, k>1$k >1$, and with Tmax∈(0,∞]$T_{max}\in (0,\infty ]$. A sufficiently regular initial data u0≥0$u_0\ge 0$ is also fixed. Under specific relations involving the above parameters, one of these always requiring some largeness conditions on m2+α$m_2+\alpha$, (i)we prove that any given solution to (⋄$\Diamond$), blowing up at some finite time Tmax$T_{max}$ becomes also unbounded in Lp(Ω)$L^{\mathfrak {p}}(\Omega)$‐norm, for all p>n2(m2−m1+α)${\mathfrak {p}}>\frac{n}{2}(m_2-m_1+\alpha)$;(ii)we give lower bounds T (depending on ∫Ωu0p¯$\int _\Omega u_0^{\bar{p}}$) of Tmax$T_{max}$ for the aforementioned solutions in some Lp¯(Ω)$L^{\bar{p}}(\Omega)$‐norm, being p¯=p¯(n,m1,m2,m3,α,β)≥p$\bar{p}=\bar{p}(n,m_1,m_2,m_3,\alpha ,\beta)\ge \mathfrak {p}$;(iii)whenever m2=m3$m_2=m_3$, we establish sufficient conditions on the parameters ensuring that for some u0 solutions to (⋄$\Diamond$) effectively are unbounded at some finite time. Within the context of blow‐up phenomena connected to problem (⋄$\Diamond$), this research partially improves the analysis in Wang et al. (J Math Anal Appl. 2023;518(1):126679) and, moreover, contributes to enrich the level of knowledge on the topic. [ABSTRACT FROM AUTHOR]

This archaeometric study aims at characterizing the archaeological finds belonging to the lithic industry from La Calvera rock shelter (Camaleño, Cantabria) and at hypothesizing the possible provenance of each material. The site, located in the mountainous area of Picos de Europa National Park (more than 1000 m a.s.l.) close to the megalithic complex of Peña Oviedo, is characterized by the presence of hearths and charcoal remains, ancient pottery, and a rich lithic assemblage composed of siliceous rocks dating back to >8000 BP and linked to the first Holocene occupations of the Cantabrian Mountains. For the study of the rock shelter's lithic assemblage, a multi-analytical approach was used: SEM-EDS and XRD analyses were performed to define the microtextural characteristics of samples and to identify the amorphous/crystalline phases; physical and mechanical tests were conducted to define the petrophysical properties (density, porosity, imbibition and saturation indexes, mechanical strength) of the samples. Preliminary data of chemical compositions, obtained by portable XRF, are also presented. The results show that the different siliceous materials (quartzite, cherts, hyaline quartz) can be distinguished through the basic analytical techniques used here. In addition, most of the archaeological samples have mineralogical and petrographic features similar to the natural samples coming from nearby outcrops, corroborating the hypothesis of a local material supply. The presence of local sources of useful raw materials could have favoured the site's occupation. Finally, the diverse compositional and textural feature of the analysed materials result in different mechanical properties (porosity, density, hardness, workability), so they likely had different uses and technical functions. [ABSTRACT FROM AUTHOR]

The following fully nonlinear attraction–repulsion and zero-flux chemotaxis model is studied: (♢) u t = ∇ ⋅ (u + 1) m 1 − 1 ∇ u − χ u (u + 1) m 2 − 1 ∇ v + ξ u (u + 1) m 3 − 1 ∇ w + λ u − μ u r in Ω × (0 , T m a x) , τ v t = Δ v − ϕ (t , v) + f (u) in Ω × (0 , T m a x) , τ w t = Δ w − ψ (t , w) + g (u) in Ω × (0 , T m a x). Herein, Ω is a bounded and smooth domain of R n , for n ∈ N , χ , ξ , λ , μ , r proper positive numbers, m 1 , m 2 , m 3 ∈ R , and f (u) and g (u) regular functions that generalize the prototypes f (u) ≃ u k and g (u) ≃ u l , for some k , l > 0 and all u ≥ 0. Moreover, τ ∈ { 0 , 1 } , and T m a x ∈ (0 , ∞ ] is the maximal interval of existence of solutions to the model. Once suitable initial data u 0 (x) , τ v 0 (x) , τ w 0 (x) are fixed, we are interested in deriving sufficient conditions implying globality (i.e., T m a x = ∞) and boundedness (i.e., ‖ u (⋅ , t) ‖ L ∞ (Ω) + ‖ v (⋅ , t) ‖ L ∞ (Ω) + ‖ w (⋅ , t) ‖ L ∞ (Ω) ≤ C for all t ∈ (0 , ∞)) of solutions to problem (1). This is achieved in the following scenarios: ⊳ For ϕ (t , v) proportional to v and ψ (t , w) to w , whenever τ = 0 and provided one of the following conditions (I) m 2 + k < m 3 + l , (II) m 2 + k < r , (III) m 2 + k < m 1 + 2 n is accomplished or τ = 1 in conjunction with one of these restrictions (i) max [ m 2 + k , m 3 + l ] < r , (ii) max [ m 2 + k , m 3 + l ] < m 1 + 2 n , (iii) m 2 + k < r and m 3 + l < m 1 + 2 n , (iv) m 2 + k < m 1 + 2 n and m 3 + l < r ; ⊳ For ϕ (t , v) = 1 | Ω | ∫ Ω f (u) and ψ (t , w) = 1 | Ω | ∫ Ω g (u) , whenever τ = 0 if moreover one among (I), (II), (III) is fulfilled. Our research partially improves and extends some results derived in Jiao et al. (2024); Ren and Liu (2020); Chiyo and Yokota (2022); Columbu et al. (2023). [ABSTRACT FROM AUTHOR]

Collapse is a common geomorphic process in karst areas, especially on the Yunnan-Guizhou Plateau, which has a tectonic background of integral uplift. The frequent occurrence of collapse processes in karst underground caves and canyons indicates that collapses play an important role in the formation of canyons. Through an analysis of the morphology of a semicircular cliff in the Huajiang Grand Canyon and an investigation of sediments at the bottom of the cliff, a large-scale collapse event was found to have occurred. U-series dating of secondary calcium carbonate cement in the collapse breccias indicates that collapse processes occurred approximately 200 ka. According to the geomorphological evolution of the Huajiang Grand Canyon, the following geomorphic evolutionary process is proposed: underground river—cave hall—collapse of a tiankeng—tiankeng degradation—canyon formation. These findings also show that the dating of collapsed breccia cement can be effectively used to determine the development times of karst canyons and the formation ages of tiankengs. [ABSTRACT FROM AUTHOR]

We present the first stable isotope (δ13C and δ18O) speleothem record from continental Croatia retrieved from two coeval stalagmites from Nova Grgosova Cave. U-Th dates constrain the stalagmite growth history from 10 ka to the present, revealing coeval growth between 7.8 and 5.6 ka. We interpret δ18O as an autumn/winter hydrological proxy related to changes of vapor source, precipitation amount, and/or seasonal rainfall distribution, while δ13C predominantly responds to spring/summer vegetation status and soil microbial activity. We identify several centennial to millennial-scale hydroclimate oscillations during this period that result from multiple forcing factors. Along with amount and source effect, it appears that some centennial variations were governed also by seasonal moisture balance. From 9.2 to 8.8 ka BP, the local environmental setting was characterized by enhanced vegetation activity, while during the 8.2 ka event the main feature was a change in precipitation seasonality. The most prominent change, identified in both δ13C records, is a sudden decline of vegetation and soil biological activity around 7.4 ka, indicating a precipitation decrease at a time of maximum plant growth in spring and summer and likely also reduced precipitation in autumn and winter. Although small in magnitude in these speleothems, a peak in δ18O and δ13C values at 4.3–4.1 ka suggests that both summer and winter conditions were substantially drier during the 4.2 ka event, in accordance with increased Mediterranean aridity and consistent with other global climate changes reported at this time. Compared to the present North Atlantic Oscillation (NAO) influence, we assume that millennial Holocene NAO-like variations were persistent through the Holocene via their effect on modifying local/regional air temperature, vapor origin, and inter- and intrannual precipitation distribution. Anthropogenic deforestation, which was the first major human impact on the environment during the Neolithic agricultural revolution, is excluded as a leading factor in δ13C variability since the first sedentary settlements were established further to the east in more arable locations along river valleys. However, the impact of intensive mining around the cave site during the last millennium is evident, with substantial deforestation driving an increase in δ13C. [ABSTRACT FROM AUTHOR]

In this work we study stationary linear time-series models, and construct and analyse "score-matching" estimators based on the Hyvärinen scoring rule. We consider two scenarios: a single series of increasing length, and an increasing number of independent series of fixed length. In the latter case there are two variants, one based on the full data, and another based on a sufficient statistic. We study the empirical performance of these estimators in three special cases, autoregressive (AR), moving average (MA) and fractionally differenced white noise (ARFIMA) models, and make comparisons with full and pairwise likelihood estimators. The results are somewhat model-dependent, with the new estimators doing well for MA and ARFIMA models, but less so for AR models. • Estimation with Hyvärinen scoring rule in Gaussian linear time series. • Consistency and, under ARMA models, asymptotic normality. • Empirical performance for AR, MA and ARFIMA white noise models. • Results are model-dependent, optimal performances for MA and ARFIMA models. [ABSTRACT FROM AUTHOR]

During the Bronze and Iron Age, Sardinia was home of one of the most technologically advanced Mediterranean societies (the Nuragic culture). Given its key geographical location, the island was also the fulcrum of deep cultural exchanges. Toward the end of the Iron Age, Phoenicians, and especially Carthaginians and Romans, massively frequented Sardinia for different purposes. This marks an important cultural transition for the region, as the ancient Nuragic-related society terminated. At the same time, this impacted the subsistence and land use practices. Together with middle to late Holocene climate changes, the novel anthropic activities had a pivotal role in shaping the landscape around the island. However, high resolution climate and environmental records for these culturally important phases are still lacking in Sardinia. Thus, this paper explores palaeoenvironmental changes from the Bronze Age to post Iron Ages times by using carbonate speleothems from Suttaterra de Sarpis Cave (Urzulei, central east Sardinia), strategically located nearby the Or Murales Nuragic Village. U–Th ages (n = 20) indicate that five stalagmites comprehensively span the last ∼7000 years. Peculiarly, they all show an evident stratigraphic discontinuity. Age models attest that hiatuses can be at times associated with the discontinuities, spanning periods of ∼1200 to ∼200 years. Importantly, the discontinuities occurred from the Late Iron Age to the Roman period. Based on fabric observations, trace elements and δ13C- δ18O analyses, the discontinuities are primarily attributed to a progressive change of land use above the cave. We suppose that deforestation aimed to clearance for agriculture and livestock practices probably was the most impacting factor for infiltration dynamics and soil state, thus affecting the studied speleothems, although archaeological and historical data are absent for the specific study area. Instead, this is in line with the cultural transition occurring in Sardinia toward the end of the Iron Age, with novel agricultural practices imported by the overseas populations. The anthropic disturbance to the millennial-long karst equilibrium possibly overprinted the response of speleothem proxies to climate oscillations, although future higher resolution analyses are necessary to better investigate the evolution of climate during the Holocene as well as its role in the development of ancient civilizations. Indeed, this is the first speleothem-based Holocene palaeoenvironmental reconstruction accomplished in Sardinia. Considering the paucity of natural lakes in this key location, speleothems here demonstrate their potential in exploring human-driven palaeoenvironmental changes during times of cultural transitions within the Mediterranean context. • The first Holocene speleothem paleoenvironmental record from Sardinia (Italy). • Changes in geochemical and physical speleothems' properties point to variation of land use. • Land use variation is connected to cultural shifts during intra- and post-Nuragic period. [ABSTRACT FROM AUTHOR]

This article discusses recent developments in the field of speleothem paleoclimate and paleoenvironmental science. Speleothems, such as stalagmites and stalactites, have been used to reconstruct past climate and environmental conditions using methods like U-Th absolute dating and stable isotope analysis. The article highlights the use of new techniques, such as U-Pb dating and the analysis of trace elements, clumped isotopes, and fluid inclusions, to extend the time range of speleothem-based paleoclimate reconstructions. The special issue includes a range of studies from different regions and time periods, covering topics such as hydroclimate variability, stalagmite formations, rainfall dynamics, and Holocene climate features. Additionally, the article introduces a web-based tool called the SISAL webApp, which aims to increase accessibility to the Speleothem Isotope Synthesis and AnaLysis (SISAL) database. Overall, these studies contribute to a comprehensive understanding of past climate variations. [Extracted from the article]

The pyroclastic rocks belonging to the Late Eocene-Miocene volcanic activity that occurred in Sardinia between 38 and 15 Ma ago were widely used as construction materials in several Romanesque churches of the easternmost Logudoro area, as well as in large parts of the Sardinia territory. In this work, the ancient Cathedral of Nostra Signora di Castro (twelfth century) was taken as a representative case study. There is no historical or archaeological evidence of ancient quarries. Based on the geochemical, petrographic, and volcanological data on several samples from an extensive field area (approximately 150 km2), a geographical zoning of the volcanics has been recognised. In the Oschiri sector, there are three different sub-zones, which can be identified with different volcanic rocks: less fractionated rocks (Differentation Index ∼70–78); intermediately fractionated rocks (D.I. ∼76–79); and more fractionated rocks (D.I. ∼77–82). To identify the origin of the ignimbrite rocks of the Church of Nostra Signora di Castro, two statistical methods were used: stepwise linear discriminant and canonical analysis. Moreover, to define the geochemical transformation processes induced by the alteration, a comparative study of concentrations of major and trace elements measured by XRF and SEM-EDX analyses on the surface portion and the innermost areas of the stone was made. [ABSTRACT FROM AUTHOR]

Here we present the first record of Marine Isotope Stage (MIS) 7 from Sardinia, based on a U-Th-dated speleothem from Crovassa Azzurra cave, which also grew during MIS 5. Carbonate precipitation was continuous during MIS 7, while two multi-millennial hiatuses interrupted growth during MIS 5. These hiatuses occurred during times of unstable climate, but local karst-specific conditions are considered to have played an important role as well. δ13C values mostly reflect soil bioproductivity and vegetation density. During less humid periods these values reflect bedrock δ13C values, because of a semi-closed system and/or sulphuric acid-driven bedrock dissolution. δ18O changes were governed by the interplay of rainfall amount and moisture source. Disentangling these two effects was possible by comparing δ13C and δ18O values, whereby both isotopes co-vary during periods when δ18O was dominated by the amount effect. Changes in the relative proportion of Atlantic and Mediterranean moisture sources was the main control on δ18O at times when δ18O was decoupled from δ13C. δ18O variations during MIS 5 are synchronous with Greenland stadials (GS) and interstadials (GI) GS 26, GI 25, GI-GS 22, GI-GS 21. With the exception of GS 22, these climate oscillations did not affect soil bioproductivity, and δ18O mirrors the relative proportion of Atlantic and Mediterranean moisture sources. GS 22 was a prominent arid period in Sardinia, in accordance with other regional palaeoclimate archives. High soil bioproductivity is indicated by δ13C values for MIS 7e and MIS 7c-a; the latter interval was characterized by a 30 kyr-long time span of warm and humid conditions in Sardinia. Soil bioproductivity decreased markedly during MIS 7d and the climate became drier. The latter period, also constrained by δ18O data, lasted significantly shorter in Sardinia than in central Europe. As indicated by changes in δ13C and δ18O relationships, variations in moisture source are also recorded for MIS 7, with Mediterranean-dominated rainfall during MIS 7e and 7c followed by a shift toward Atlantic-dominated rainfall. • A Mediterranean palaeoclimate archive recording MIS 7 and MIS 5. • The first MIS 7 palaeoclimate record from Sardinia. • Hints of moisture source variability during pre-Holocene interglacials. [ABSTRACT FROM AUTHOR]

The study focused on the volcanic glass used in the production of bedding mortars and concrete of the Roman theatre (I cent. AD) of the Nora site. The volcanic glasses were frequently used as aggregate and with pozzolanic function in all hydraulic mortars of the different sectors of the building (e.g., concretes of tribunalia vaults and external niches, jointing and foundation mortars of cavea tier ashlars, brick bedding), together with mainly quartz-feldspar sands, local Oligo-Miocenic andesitic-dacitic volcanics and Palaeozoic and Tyrrhenian sedimentary rocks. These volcanic glasses show characteristics closer to obsidian than to natural pozzolan normally used in the Roman period. They have definitely not sourced locally, unlike the other components that make up the aggregate. To identify their provenance, a petrochemical comparison between several samples taken from the theatre mortars and the volcanic outcrops of some probable Sardinian source areas is made. The use of the not local pozzolanic glass is a technical innovation in the mortars of the Nora archaeological site, and considering the wide use of obsidians in the prehistoric periods for the production of tools, significant considerations about its origin, procurement and use are made. [ABSTRACT FROM AUTHOR]

A multiproxy record from a stalagmite collected from Torgashinskaya Cave (Southern Siberia, Russia) and growing between ca. 6 and 3.8 ka shows evidence for regional climatic changes occurring at ca. 5 ka. Interpretation of stable isotope ratios (δ18O and δ13C) and fluorescence data (intensity and wavelength of the emitted fluorescence) suggests that the interval between ca. 5 and 4.2 ka was generally warmer and drier than the interval between ca. 6 and 5 ka. The observed bipartitioning of the climate, attributable to the so-called 'middle-late Holocene transition', has a striking similarity to changes in K+ and Na+ concentration of Greenland ice cores (taken as indicators of the strength of the Siberian High and Icelandic Low, respectively), in the abundance of hematite-stained grains in subpolar North Atlantic sediments and, to lesser extent, in the summer Asian monsoon intensity deduced by δ18O from Chinese speleothems. In particular, the δ18O record at Torgashinskaya Cave can be interpreted as mostly driven by temperature changes. Besides several episodes of drift towards higher temperatures, it also strongly suggests the presence of short cooling events centered at 4.1+0.08/ -0.07 , 4.85+0.05/ -0.06 , 5.1+0.09/ -0.09 , 5.3+0.08/ -0.07 and 5.8+0.12/ -0.13 ka. Notably, the last three such events are in very good correspondence with spikes in the K+ and Na+ concentration of Greenland ice cores. Instead, the cooling around 4.1 ka could be the local response to the 4.2 event, a cold/dry episode identified in several records in the Northern Hemisphere. This suggests that δ18O of speleothem calcite from this area could be a useful proxy for defining the evolution of the Siberian High and its effect on the wider regional climate. • The first speleothem-based middle-to-late Holocene paleoclimate reconstruction from a Siberian underexplored area. • δ13C-δ18O and fluorescence timeseries reveal temperature and rainfall variations at decadal resolution. • A cold-wet to warm-dry climate shift is related to the Siberian High dynamics during the middle-late Holocene transition. [ABSTRACT FROM AUTHOR]

Abstract In this study, we report the results of a micro-destructive analysis of stone materials used for the realization of the Mont'e Prama statues, important limestone sculptures dated to the Early Iron Age (Late Nuragic period: 9th–8th cent. BC) from central-western Sardinia. Although numerous historical, archaeological and geological studies have been already performed on these artefacts, up to date, information and data about reliable location of raw materials supply and chemical-physical weathering processes occurring in the millennia are missing. In order to fill this gap and provide fundamental information for the proper conservation and preservation of these artefacts, twenty-two micro-samples from limestone Nuragic statues were analysed. Laser-Induced Breakdown Spectroscopy (LIBS), with the support of petrographic and mineralogical (optical microscopy and X-ray diffraction) analyses, was applied for defining the chemical composition of the rocks, as well for studying the surface features of the sculptures. This latter approach was useful to define alteration processes occurring on the surface and to identify the possible ancient treatments used for colouring or preserving the statues. LIBS results on the Mont'e Prama statue materials were processed by blind clustering analysis, including reference data of fifteen limestones sampled from the nearest supply areas. Hypotheses on provenance of raw materials and on surface treatments/secondary phases are finally discussed and proposed, highlighting the merits of the LIBS method in archaeometric provenance studies. Highlights • LIBS-XRPD-OM multidisciplinary approach defined the limestone features of statues. • Blind clustering analysis on LIBS data (Graph Theory based) identified stone origin. • Chemical-physical alteration brought out the rock microstructural characteristics. • CaCO 3 -matrix dissolution led to a prevailing quartz-feldspar composition on surface finds. • Surface alteration removed at least in part any original treatments on stone statues. [ABSTRACT FROM AUTHOR]

The work aims to define the origin of the architectural stone elements worked by Romans and reused in the St. Saturno Basilica, between the late Antiquity and Romanesque periods. Thus, different rocks (marbles, various facies of limestones, volcanic rocks) used to construct the ancient building were sampled and analysed. All the different kinds of stones were sampled from the Basilica, taking precise reference to the various construction phases and structural changes of the monument occurred in the centuries. The sedimentary and volcanic lithologies belong to the local outcrops of Cagliari Miocenic geological formation (e.g. limestone) and to other volcanic outcrops of south Sardinia, respectively. By means of a multimethod archaeometric study (mineralogical-petrographic observations on thin sections and 18O vs 13C stable isotope ratio analysis), the provenance of classical marbles used for manufacturing Roman architectural elements (column shafts, bases, capitals, slabs, etc.) were defined, which are thought to come from extraregional sources. The results show that the marbles come mainly from Apuan Alps (Italy) and subordinately from Greek quarrying areas. [ABSTRACT FROM AUTHOR]

The stone used on the monuments, especially if they come from ancient times (e.g. medieval period), when exposed to the atmosphere, they are frequently affected by weathering and bio-deterioration processes. Thus, these latter produce various chemical and mineralogical transformations of substrate at the interface with the atmospheric agents as function of intrinsic compositional and physical characteristics of the material. Moreover, if there also are ancient treatments on the surface of geomaterials, the investigation field is further complicated. This research aims to analyse the surfaces of different volcanic lithology (basalts, andesite, pyroclastic rocks) used in the medieval Romanesque churches of Sardinia (XI-XIV cent.) having high historical- architectural and cultural relevance. By mineralogical and petrographic analysis (OM) and other different analytical methods (XRPD, colorimetry) the investigations addressed to define: i) petrographic features of volcanic rocks substrate; ii) chemical and mineralogical composition of coatings/crusts and any salt fanoand cryptoefflorescence; iii) compositional and microstratigraphic characterization of ancient treatments (i.e., Ca-oxalate films) on the surface of facades; iv) chromatic modifications of surface with respect to the substrate due to the alteration processes. The results show the incidence of several factors in the alteration process, as function of the occurred time, petrophysical features and composition of geomaterials, their position in the monument structure, exposition to the weathering processes, microclimatic characteristics, environmental conditions. [ABSTRACT FROM AUTHOR]

Abstract Three stalagmites, which grew in the high altitude (∼1800 m a.s.l.) Piani Eterni karst system (northern Italy), represent the longest speleothem palaeoclimate-environmental record from the southern Alps. U-Th dating shows their discontinuous formation during Marine Isotope Stage (MIS) 10, 8, 7d, 6 and 5d–b, with carbonate deposition prevented during both full interglacial and full glacial stages. Speleothem formation was inhibited during interglacial peaks because local base level rise, connected to global climate changes, caused the alluviation of the main epiphreatic levels of the cave system. Drainage of the hydrological pathways, caused by the progressive decrease of rainfall and the accumulation of a perennial snow pack, stopped carbonate deposition during glacials. Thus, Piani Eterni speleothems function as indicators of transitional interglacial to glacial (IG–G) climate periods over the last ∼400 thousand years (kyrs). Analysis of δ18O and δ13C suggest that: i) seasonal snow melt occurred in these high altitude terrains during IG–G times, allowing meteoric water to efficiently penetrate the karst network; ii) soils were restored during MIS 5c–b, but absent during MIS 10, 8, 7d and 6 due to denudation of the karst surfaces; and iii) rainfall perturbations modulated the IG–G shifts in the southern Alps. Rainfall variation is connected to solar radiation changes at orbital timescales during MIS 5c–b, and mimics Dansgaard-Oeschger (DO) cycle variability during DO 23 and 22. DO cycle-like variability is also suspected during MIS 10, 8 and 6. The most important result is that, from a geochemical perspective, this study demonstrates that drivers of δ18O in southern alpine speleothems are similar to Mediterranean, Middle Eastern and Asian speleothems in that they are prevalently controlled by the rainfall amount effect. This contrasts with speleothem records from the more continental northern alpine sector where the air temperature effect on δ18O of precipitation dominates. Highlights • The longest speleothem palaeoclimate-environmental record from the Southern Alps. • Speleothems as indicators of interglacial-to-glacial transition over the last ∼400 kyr. • Seasonal snow melting occurred during interglacial-to-glacial times. • Soils restored during MIS 5c-b, but were absent during MIS 10, 8, 7d and 6. • Mediterranean response of δ18O in Southern Alpine speleothems (rainfall amount). [ABSTRACT FROM AUTHOR]

Here we track the water-table position and temperature of the Mount San Giovanni aquifer (Iglesiente-Sulcis mining district, SW Sardinia, Italy) during the past 600 ka by determining the ages (U/Th dating) and stable isotope compositions (δ 18 O, δ 13 C and Δ 47 ) of a variety of subaqueous carbonate speleothems (e.g. calcite spars, dogtooth calcite crystals and calcite coatings). Clumped isotopes ( Δ 47 ) provide quantitative estimates of carbonate formation temperatures (and thus water temperatures) that are independent of the oxygen isotope composition of water (δ 18 O w ). Then, the δ 18 O w of the paleo-water has been reconstructed from the clumped isotope temperature (T Δ 47 ) and the δ 18 O of the carbonate (δ 18 O c ). We find that some high-temperature calcite spars formed prior to 600 ka at temperatures above ~120 °C. Lower-temperature spars (~70 °C) precipitated at ~400 ka, and cold-water subaqueous speleothems (~10–20 °C) formed in perched ponds at different levels of the karst systems between 410 ka and 110 ka, while coeval precipitation of subaerial flowstones occurred in the upper level of the shallower caves until 82 ka. We infer that the groundwater level dropped by ~120 m from ~400 to ~250 ka, with a relatively rapid rate of ~0.8 mm/yr. Considering the tectonic stability of Sardinia during the Quaternary, this high rate derives from climate driven geomorphological processes at the surface rather than tectonic uplift. The δ 18 O values of the paleo-aquifer water range from −6.0 ± 0.7‰ during MIS 5c, and similar to modern cave water values (−5.1‰), to −7.7± 0.4‰ during the colder MIS 8. These values indicate that the groundwater reflected the δ 18 O signal of meteoric water, with no significant contributions from metasomatic and metamorphic waters. The observed δ 18 O w variability can be explained by glacial/interglacial paleoclimate changes affecting rainfall δ 18 O (and thus groundwater δ 18 O). We conclude that clumped isotope thermometry on subaqueous carbonate speleothems is a useful tool for tracking paleo-aquifer temperatures and δ 18 O w reconstructions. [ABSTRACT FROM AUTHOR]

Chemical and physical proxy data from a precisely dated early last glacial (∼113–110 ka, MIS5d) Sardinian stalagmite reveal a sub-millennial-scale, cool-dry climate event centered at 112.0 +0.52 / -0.59 ka, followed by a rapid return to warm-wet conditions at 111.76 +0.43 / -0.45 ka. Comparison with regional speleothem records and the palaeotemperature proxy record from the NGRIP ice core (Greenland) suggests that this event corresponds to Greenland Interstadial (GI) 25b and 25a, an intra-interstadial climate oscillation within GI-25, according to the recent Greenland stratigraphic framework. The speleothem age is in reasonable agreement (within 0.8 kyr) with that of the corresponding event in Greenland based on the GICC05modelext ice chronology but is older by about 3.7 kyr than the Greenland age based on the AICC2012 chronology. [ABSTRACT FROM AUTHOR]

The aim of this work is the physical and mineralogical-petrographic characterization of the mortars from the Baths with Heliocaminus, a special and unique architectural building in the complex of the Hadrian's Villa in Tivoli. Thirty samples were investigated for composition and physical properties (density, porosity, water absorption, mechanical strength, particle size distribution of aggregate, etc.), representative of eight mortar groups: cubilia bedding mortar, brick bedding mortars, floor-coating and wall-coating bedding mortars, floor ( rudus) and wall conglomerates ( trullisatio), vault concretes, and lime plasters ( arriccio). Physical parameters, together with the microscopic analysis and binder/aggregate ratio determined in three ways using image analysis (on thin sections and on specimens) and weight-data from dissolution of binder, have shown an interesting relationship between the physical-compositional characteristics and the function of mortars within the structure of the Heliocaminus baths. To identify the minerals and the reactant phases between binder and aggregate, as well as the hydraulic degree, selected samples were analyzed with x-ray powder diffraction, thermogravimetry, and differential scanning calorimetry techniques. The obtained results provide a close relation between pozzolanic characteristics and physical-mechanical properties of the mortars (i.e., punching strength index). [ABSTRACT FROM AUTHOR]

The pyroclastic rocks, belonging to the calcalkaline volcanic activity occurred in Sardinia between 32 and 11 Ma ago, were widely used as construction material in several Romanesque Churches of the easternmost Logudoro, as well as in the Sardinia territory. In this work was taken as a case study the Church of Nostra Signora di Otti (12th cent.). There are no historical or archaeological evidences of the ancient quarries. Based on the geochemical, petrographic and volcanological characters of several samples from an extensive field area (approximately 150 kmq), a geographical zoning of the Oligo-Miocenic volcanics has been recognised. Internally to the Oschiri sector, according to TiO vs Differentiation Index diagram, there are three different sub-zones with pyroclastics: less fractionated (D.I. ~70 ÷ 78); intermediate fractionated (D.I. ~76 ÷ 79); more fractionated (D.I. ~77 ÷ 82). To identify the origin of the ignimbrites of the Church, two statistical methods have been used: stepwise linear discriminant and canonical analysis. Moreover, to define the geochemical transformation processes induced by the alteration, by XRD analysis and XRF, SEM-EDS data, a comparative study of concentrations of major and trace elements measured between the surface portion and the innermost of the stone has been made. [ABSTRACT FROM AUTHOR]

The antisocial and offending behavior of youths raises a constant social concern as well as a crescent scientific interest in order to understand its causes. The objective of this study is to analyze –through the ISRD-2 selfreport instrument– the antisocial behaviors of a sample of Italian students and the risk factors related to them. Our results confirm that in general most of the youths evaluated in this study have carried out antisocial behaviors of mild severity. The study also explored different risk factors –individual, social and contextual– linked to the youth criminal behavior. The detection of these risk influences can be relevant for a better understanding of juvenile delinquency and for its more efficient prevention. [ABSTRACT FROM AUTHOR]

A methodological proposal was developed for the study of prehistoric siliceous artefacts which includes the use of smartphone photography as an analytical tool. Different kinds of materials (cherts, rock crystal and quartzite) were sampled from the lithic assemblage of La Calvera rock-shelter (Camaleño, Spain), chosen as a case study. Each sample was photographed with a smartphone and colour features were compared with portable and non-destructive standardised techniques including visible spectrophotometry, Raman, diffuse reflectance Fourier transform infrared spectroscopy and portable X-ray fluorescence. The obtained results suggest that smartphone image analysis is a reliable approach to characterise siliceous rocks and that it can be a valuable, cheap and fast method especially suitable for the first screening of large lithic assemblages. [ABSTRACT FROM AUTHOR]

Present climate conditions impede the formation of calcite speleothems in the gypsum caves of the semi-arid region of Sorbas (Southern Spain). However, U-Th dating reveals the uninterrupted deposition of a 46 mm-thick carbonate flowstone in the Sorbas caves from ∼78 to ∼71 ka, during Marine Isotope Stage (MIS) 5a. This indicates that the area was vegetated during this period, producing biogenic CO 2 in soils necessary for the underground deposition of the speleothem, which contrasts with the current unvegetated landscape. During MIS 5a, rainfall recharged the karst aquifer, leading to cave seepage. The development of soils and persistent water infiltration suggests a higher precipitation/evapotranspiration ratio with respect to the present, which was likely favored by lower regional temperatures and a different annual rainfall regime. δ18O and δ13C analyses testify that the speleothem recorded climate pulses synchronous, and structurally similar, with Greenland interstadial and stadial periods, with relatively wetter conditions recorded during interstadials 21.1, 20 and 19.2, and drier periods during stadials 21.1 and 20. This demonstrates that the climate in the desert-like environment of Sorbas is sensitive to inter- and intra- hemispherical triggers, such as the extent of Northern ice sheets and the Atlantic meridional overturning circulation. Interstadials (stadials) were also characterized by a higher (lower) Atlantic/Mediterranean moisture source ratio. For the first time, we show that carbonate speleothems formed in arid gypsum caves can record reliable palaeoenvironmental information spanning multiple millennia, procuring proxies for detailed palaeoclimate reconstructions. Such speleothems are thus excellent candidates for understanding past climate dynamics and patterns in desert-like gypsum terrains. • A rare calcite speleothem from Sorbas arid region recorded MIS5a palaeoclimate. • MIS 5a climate in Sorbas was more humid than today. • Greenland stadials/interstadials impacted MIS5a rainfall dynamics. [ABSTRACT FROM AUTHOR]

Detailed geomorphological analysis has revealed that subhorizontal gypsum caves in the Northern Apennines (Italy) cut across bedding planes. These cave levels formed during cold periods with stable river beds, and are coeval with fluvial terraces of rivers that flow perpendicular to the strike of bedding in gypsum monoclines. When rivers entrench, renewed cave formation occurs very rapidly, resulting in the formation of a lower level. River aggradation causes cave alluviation and upward dissolution (paragenesis) in passages nearest to the river beds. The U-Th dating of calcite speleothems provides a minimum age for the formation of the cave passage in which they grew, which in turn provides age control on cave levels. The ages of all speleothems coincide with warmer and wetter periods when CO2 availability in the soils covering these gypsum areas was greater. This climate-driven speleogenetic model of epigenic gypsum caves in moderately to rapidly uplifting areas in temperate regions might be generally applicable to karst systems in different geological and climatic conditions. [ABSTRACT FROM AUTHOR]

Ice core records from Greenland provide evidence for multiple abrupt cold–warm– cold events recurring at millennial time scales during the last glacial interval. Although climate variations resembling Dansgaard–Oeschger (DO) oscillations have been identified in climate archives across the globe, our understanding of the climate and ecosystem impacts of the Greenland warming events in lower latitudes remains incomplete. Here, we investigate the influence of DO-cold-to-warm transitions on the global atmospheric circulation pattern. We comprehensively analyze δ18O changes during DO transitions in a globally distributed dataset of speleothems and set those in context with simulations of a comprehensive high-resolution climate model featuring internal millennial-scale variations of similar magnitude. Across the globe, speleothem δ18O signals and model results indicate consistent large-scale changes in precipitation amount, moisture source, or seasonality of precipitation associated with the DO transitions, in agreement with northward shifts of the Hadley circulation. Furthermore, we identify a decreasing trend in the amplitude of DO transitions with increasing distances from the North Atlantic region. This provides quantitative observational evidence for previous suggestions of the North Atlantic region being the focal point for these archetypes of past abrupt climate changes. [ABSTRACT FROM AUTHOR]

The main quarrying area of the Mulargia ignimbrite, used mainly to produce rotary millstones during the Hellenistic and Roman age, has been identified and sampled in order to update and complete the petrographic and geochemical database by employing standard analytical methods (optical microscopy and ICP-AES/MS spectrometry). The combination of petrographic and geochemical data concerning the Tertiary rhyodacitic to rhyolitic ignimbrites outcropping in central west Sardinia, previously very poor, form a helpful tool for future work on this important typology of volcanic millstones. The data bank obtained has been used to verify the geological source of eight millstones discovered in different rural settlements of Hellenistic Numidia and Roman Africa Proconsularis supposed by archaeologists to be made of ignimbrite from Mulargia. The results of the petro-archaeometric study confirmed a Sardinian origin for these millstones and represent one of the very few analytical proofs of their effective export to North Africa. [ABSTRACT FROM AUTHOR]

This paper aims to ascertain the provenance of white and greyish marbles used for decorating the Heliocaminus Baths, one of the most ancient thermal complexes inside the Hadrian's Villa at Tivoli (Italy). Fifteen marble samples have been macroscopically described and investigated by means of mineralogical and petrographic observations of thin sections, XRF chemical analyses of major and some trace elements, and stable isotope ratio analysis of carbon and oxygen. The collected data show that the majority of the marbles analysed come mainly from the Apuan Alps basin (Carrara) and subordinately from several Greek (Mt. Penteli and Thasos Islands) and Turkish (Afyon and probably Ephesus districts) quarrying areas. [ABSTRACT FROM AUTHOR]

The Roman municipium of Forum Sempronii (Fossombrone, Marche) was located along the 'Via Consolare Flaminia', in the stretch of road where it ran along the final sector of the valley of the River Metauro ( Mataurus). The ancient colony of Forum Sempronii, which is cited by Strabo, Pliny, and Ptolemy, was found in the second century BC, probably on the site of an earlier community and its activity continued until the end of the fifth century AD. During ancient and more recent archaeological excavations, many fragments of coloured stones and marbles, and some white marble sculptures have been unearthed. In this paper, we report the results of the provenance identification of the white marbles used for the sculptures found in the archaeological site of Forum Sempronii and now displayed at the local archaeological museum. The determination of the source origin of the white marbles used for the sculptures has been established by mineralogical-petrographic and geochemical analyses. Microscopic study of thin sections together with carbon and oxygen stable isotope ratios indicate that more than one type of white marbles was used: Pentelikon, Lunense, and Thasian. [ABSTRACT FROM AUTHOR]

• The first genetic model for wavy flowstone carbonate deposits. • Wavy flowstones only form because of high rainfall rates (storms) • Wavy flowstones are new promising hydroclimatic indicators. Speleothems show an array of shapes. Flowstones are commonly tabular sheet-like deposits, which cover cave floors and walls. They can procure detailed information about past hydrogeological conditions through their morphology, geochemical composition and stratigraphic properties, which in turn are related to the climate conditions at the surface. This is possible if the climate and environmental factors controlling the formation of these deposits are well understood. In Bossea Cave (north-east Italy), we have investigated highly symmetrical wavy flowstones that have never been described in detail before. These deposits show a cyclical repetition of sloped and sub-vertical layers, with knickpoints migrating downslope. This paper investigates the origin of these peculiar carbonate deposits, using: i) terrestrial laser scanning surveys; ii) petrographic observations; iii) oxygen and carbon stable isotope analyses; iv) hydrochemical monitoring data of feeding waters. According to these analyses, we have generated a genetic model that demonstrates: 1) laminar flow of CaCO 3 –rich water prevails during the deposition of the flowstone; in accordance, the final flowstone architecture does not appear to be influenced by random irregularities of the underlying bedrock substrate. 2) The peculiar morphology is inherited by ripples occurring in the flowing water films during carbonate deposition, which trigger the precipitation of regularly spaced CaCO 3 deposits along the bedrock slopes. Because of these ripple-induced initial deposits, calcite then deposits as sloped and sub-vertical layers, giving rise to a wavy-like morphology. 3) Wavy calcite layers are only deposited after heavy rainfall events occurred within two to four consecutive rainy days (10 to 20 mm/hour during rainfall peaks; average rates between 3.5 and 7.0 mm/hour); in contrast, calcite deposition cannot occur during low rainfall events (less than 5 mm/hour during rainfall peaks, average rates around 0.8 mm/hour). We therefore propose that the studied wavy flowstones are hydroclimatic indicators, testifying the occurrence of flashy type recharge related to heavy rainfall events. Similar deposits could record these same hydro-climatic conditions in other karst areas. In recent decades, storms have caused more frequent flooding in highly populated Mediterranean areas, especially in Italy. Wavy flowstones may offer a new archive to gain a better understanding of the long-term dynamics of intense precipitation events and, thus, help to improve future climate scenarios. [ABSTRACT FROM AUTHOR]

This paper deals with the "modern" plaster mortars based on air lime, hydraulic lime, and cement used between the 1950s and 1990s of the last century, taking, as a case study, a historical building of the Cagliari city whose foundations and ground floor are cut into in-situ limestone. Different plaster layers (i.e., arriccio and intonachino, paint), applied on the excavated limestone walls, were collected from cave-room. All samples were analysed by optical and electron (SEM-EDS) microscopy and X-ray diffractometry (XRD) in order to define their microstructures, textures and compositional features. In addition, real and bulk density, water and helium open porosity, water absorption kinetic, and saturation index were measured. By microscopic imaging analyses, the binder/aggregate ratio as vol.% was determined. Results revealed that cement mortars, composed mainly of C-S-H, C-A-H, and C-F-H phases, given their high hydraulicity, low open porosity, and a rigid behaviour, showed a good chemical but not physical–mechanical adherence, as they were often found detached from the substrate and frequently loaded with salt efflorescence. On the contrary, the hydraulic lime-based mortars, characterised by a binder composed of C-S-H and C-A-H phases and calcite derived from the portlandite carbonation, showed a greater affinity with limestone substrate and other plasters. Thus, they are more suitable to be used as a repair mortar, showing a long durability on the time. The thin air lime-based plasters (intonachino) showed a good adhesion to the substrate, exerting their coating function better than the harder, cement-based mortars. Lime-based wall paints have a good chemical adhesion and adaptability to the irregular surface of the substrate, due to low thickness of lime paint layers (<1 mm) that confers an elastic physical behaviour. [ABSTRACT FROM AUTHOR]

This study deals with the mortars and subordinately rocks collected from the archaeological site of Cap de Forma, that is a "Bien de Interés Cultural" located on a cape along the southeastern coast of Menorca (Balearic Islands, Spain). Cap de Forma consists of different structures belonging to different periods and civilization phases: a fortified settlement of Talaiotic age, built in cyclopean technique and including three rooms and a rainwater cistern; a nearby necropolis of tombs (cuevas) excavated into the cliff; a more recent site occupancy testified by plastering of the cistern; a house-fort (pecheña casa-quartel), a lookout point of the 17th–18th century. Compositional features and mineralogy of mortars and rocks were investigated by optical microscopy and X-ray diffraction. Physical properties (density, porosity, water saturation and water saturation coefficients and mechanical strength) were also determined. This work is aimed at characterizing these archaeologic remains to understand the building technique, the choice of raw materials and possibly their provenance, taking into account the age and civilization they belong to. Results indicate that cocciopesto-rich mortars were used in the cistern watertight and other ancient structures linking from a Roman age. The cocciopesto seems to derive from local pottery even if some evidence would suggest the contrary, whereas the source of the binder is definitely the local Mg-rich limestone. The house-fort was plastered with gypsum-based mortars in the 17th–18th century. The most likely source of raw gypsum was the island of Mallorca where some quarries were opened in the same period. Mechanical and physical tests reveal a strong state of decay that requires conservation actions. This work sheds light on a poorly studied monument, better constraining the different phases of its occupation. Some interesting questions, such as the cocciopesto provenance, are still open. [ABSTRACT FROM AUTHOR]

Abstract: We present numerical results on a complex dynamical model for the aggregation of many individual rankings of alternatives by the pairwise majority rule under a deliberative scenario. Agents are assumed to interact when the Kemeny distance between their rankings is smaller than a range . The main object of interest is the probability that the aggregate (social) ranking is transitive as a function of the interaction range. This quantity is known to decay fast as increases in the non-interacting case. Here we find that when such a probability attains a sharp maximum when the interaction range is sufficiently large, in which case it significantly exceeds the corresponding value for a non-interacting system. Furthermore, the situation improves upon increasing . A possible microscopic mechanism leading to this counterintuitive result is proposed and investigated. [Copyright &y& Elsevier]

The Antas site (SW Sardinia, Italy) is of fundamental cultural importance because it testifies the presence of Nuragic, Punic and Roman civilizations from the second millennium to the third century BC. This work focuses on the Punic and the Roman temples and aims to define their conservation state and provenance of construction materials through their minero-petrographic and physical-mechanical characterization. In addition, artificial geomaterials used in restoration works comprising a partial anastylosis and a consolidation intervention on the monument, were investigated to evaluate the aesthetic, petrographic and petrophysical compatibility with the original materials. The results indicate that Punic builders preferred to use a porous sandstone coming from at least few kilometres away from the site. By contrast, Roman builders opted for the use of the less porous and harder local metadolostones, more difficult to quarry and to hew but promptly available in the surrounding area. The Roman temple still preserves decorative architectural elements (as the Pronao threshold and the mosaic tesserae) whose source is definitely not local, suggesting the import of these materials. As regards artificial materials, a new material was found within the Punic temple consisting of a sandstone-like rock (i.e., lime based sandy-conglomeratic geomaterial) and characterized by higher mechanical strength and lower porosity. [ABSTRACT FROM AUTHOR]

We investigate the determinants of students' university choices (where to study and which field) by linking micro-data provided by the Italian National Student Archive (ANS) on a cohort of students enrolled for the first time at the university in a.y. 2017/18 with socioeconomic indicators related to the territorial areas and other information concerning universities, fields of study and degree programmes provided by national surveys on graduated students. The aim of the analysis is to propose a set of indicators of attractiveness of tertiary education institutions that are suitable for making comparisons among fields of study and degree programmes between and within universities. To this end, students' choices to attend bachelor's degree studies outside their region of residence have been modelled within the generalised mixed-effect models framework. We show how the setting of alternative model parametrisations and the adjustment for different sources of heterogeneity in the data enable us to build up measures that are suitable to investigate the characteristics of institutions attractiveness. The results of the analysis enable us to assess and distinguish the roles played by the university, the field of study and other factors that are endogenous to tertiary education institutions in determining the power to attract students from other regions. [ABSTRACT FROM AUTHOR]

The Toirano karst system is located in the Ligurian Alps (north Italy), around 4.5 km inland from the coastline and carved in Middle Triassic dolostone. It comprises five cave levels over a 154 m altitudinal range, specifically Ulivo (340 m a.s.l.), Colombo (247 m a.s.l.), Upper Santa Lucia (215 m a.s.l.), Lower Santa Lucia (201 m a.s.l.) and Bàsura (186 m a.s.l.) caves. The system is active at lower altitudes, as testified by the thermal spring currently located at 70 m a.s.l. along the Varatella valley. Speleogenesis was attributed to the action of epigenic processes by other authors. However, the extraordinary geodiversity of the underground morphologies and deposits are at odds with this interpretation. Accordingly, this work investigates the genesis of the Toirano karst system, in relation to the landscape evolution of the surrounding area. A detailed morphological and mineralogical investigation of cave geoforms and deposits, together with the presence of the active low thermal sulphide spring on the Varatella valley and only ~100 m below the Bàsura Cave, sustain the hypothesis of a hypogene origin of the caves. This work shows that most of the caves formed close to the former water table (base) level, in turn determined by the mean sea level. Geochronological analyses, including U/Th (n = 13) and cosmogenic burial (n = 1) dating, together with an estimated incision rate of the Varatella valley of around 0.1 mm y−1, have allowed to assess the age of the highest cave (Ulivo) at around 2.7 Ma, Colombo at ~1.8 Ma, Upper Santa Lucia at ~1.5 Ma, Lower Santa Lucia ~1.3 Ma and Bàsura at ~1.2 Ma. Estimated palaeotemperature attained through isotope analyses and fluid inclusions on speleothems suggest that the temperature of rising waters was lower than 50 °C and possibly ranging between ~12 and ~20 °C, indicating that hydrothermal fluids were not the main driver of speleogenesis, at least in the late speleogenic phases. Additionally, sulphuric acid speleogenesis by-products were not identified. Accordingly, hypogenic speleogenesis occurred because of the action of low temperature CO 2 -rich rising fluids. A late stage of epigenic speleogenesis has been detected because of the clear evidences of condensation-corrosion morphologies, taking place since ~150 ka (possibly earlier) when caves were finally connected to the surface because of valley enlargement. Besides uncovering the genesis of the Toirano karst system, this study demonstrates that the combination of local geology, surface vs underground geomorphological observations, climate change vs landscape evolution evaluation and geochemical data is of key importance for interpreting subsurface land-shaping processes. • The speleogenesis of one of the most iconic Italian cave system reported in detail. • The Toirano karst system was originally formed by rising fluids (hypogenic speleogenesis). • Late stage epigenic cave processes can erase original hypogenic morphologies. [ABSTRACT FROM AUTHOR]

Understanding the phenomenon of intra- and international student mobility has become increasingly relevant to the organization of tertiary education systems. Using microdata information provided by the Italian National Student Archive on the cohorts of students enrolled at university in the academic years 2011–12 and 2014–15, we consider a network analysis approach to investigate the incoming and outgoing student flows between territories and universities. More specifically, the paper aims to shed light on the dynamics of Italian student mobility networks at both the bachelor's and master's degree levels by considering attractiveness indicators combined with network centrality measures, clustering techniques for network data and explanatory models. We analyze the partition of the global network structure by means of blockmodeling analysis and we explain the determinants of the differences among universities in attracting students adopting a quantile regression analysis. • The paper investigates the incoming and outgoing student flows between territories and universities. • Microdata on two student cohorts are adopted. • Hub and authority scores highlight the most relevant Italian provinces and universities. • An asymmetric core–periphery network structure emerges by means of blockmodeling analysis. • Quantile regression analysis explains the determinants of the differences in university attractiveness. [ABSTRACT FROM AUTHOR]

The orthoquartzite Imawarì Yeuta cave hosts exceptional silica speleothems and represents a unique model system to study the geomicrobiology associated to silica amorphization processes under aphotic and stable physical–chemical conditions. In this study, three consecutive evolution steps in the formation of a peculiar blackish coralloid silica speleothem were studied using a combination of morphological, mineralogical/elemental and microbiological analyses. Microbial communities were characterized using Illumina sequencing of 16S rRNA gene and clone library analysis of carbon monoxide dehydrogenase (coxL) and hydrogenase (hypD) genes involved in atmospheric trace gases utilization. The first stage of the silica amorphization process was dominated by members of a still undescribed microbial lineage belonging to the Ktedonobacterales order, probably involved in the pioneering colonization of quartzitic environments. Actinobacteria of the Pseudonocardiaceae and Acidothermaceae families dominated the intermediate amorphous silica speleothem and the final coralloid silica speleothem, respectively. The atmospheric trace gases oxidizers mostly corresponded to the main bacterial taxa present in each speleothem stage. These results provide novel understanding of the microbial community structure accompanying amorphization processes and of coxL and hypD gene expression possibly driving atmospheric trace gases metabolism in dark oligotrophic caves. [ABSTRACT FROM AUTHOR]

This paper focuses on the study of different Roman mortars (renders, finishing coats), used in the construction and restoration of the Forum Traiani thermal baths (Central Sardinia, Italy), a significant example of the Roman-style architecture in Sardinia. The archaeological site is located in a high hydrogeological risk area, due to the cyclical flooding of nearby Tirso river. Moreover, the presence of thermal saline (NaCl-bearing) water spring directly in contact with mortars and building stones, also contributed to structure degradation. An analytical approach, comprising mineralogical-petrographic characterization, physical analysis and particle-size distribution of aggregate, was used for mortars characterization. In addition, pXRD analysis on mortars defined the presence of alteration minerals while the thermal characterization (TGA) gave information about binder hydraulicity degree. Further μ-XRD-associated μ-Raman spectroscopy and μ-FTIR were utilized for pigments identification on frescos. Interesting results came from two wall stratigraphic series of mortars, highlighting construction stages, ancient restoring interventions and waterproofing methods. The main pigments used on red, yellow and black frescoes were red ochre, goethite and wood charcoal respectively. [ABSTRACT FROM AUTHOR]

Although outcropping rarely in Italy, evaporite (gypsum and anhydrite) karst has been described in detail since the early 20th century. Gypsum caves are now known from almost all Italian regions, but are mainly localised along the northern border of the Apennine chain (Emilia Romagna and Marche), Calabria, and Sicily, where the major outcrops occur. Recently, important caves have also been discovered in the underground gypsum mines in Piedmont. During the late 80s and 90s several multidisciplinary studies were carried out in many gypsum areas, resulting in a comprehensive overview, promoting further research in these special karst regions. More recent and detailed studies focused on the gypsum areas of Emilia-Romagna and Sicily. Sinkholes related to Permian-Triassic gypsum have been studied in Friuli Venezia Giulia. This article reviews the state of the art regarding different aspects of evaporite karst in Italy focusing on the main new results. [ABSTRACT FROM AUTHOR]

Irisin is a myokine synthesized by skeletal muscle, which performs key actions on whole-body metabolism. Previous studies have hypothesized a relationship between irisin and vitamin D, but the pathway has not been thoroughly investigated. The purpose of the study was to evaluate whether vitamin D supplementation affected irisin serum levels in a cohort of 19 postmenopausal women with primary hyperparathyroidism (PHPT) treated with cholecalciferol for six months. In parallel, to understand the possible link between vitamin D and irisin, we analyzed the expression of the irisin precursor, Fndc5, in the C2C12 myoblast cell line treated with a biologically active form of vitamin D, 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3). Our results demonstrate that vitamin D supplementation resulted in a significant increase in irisin serum levels (p = 0.031) in PHPT patients. In vitro, we show that vitamin D treatment on myoblasts enhanced Fndc5 mRNA after 48 h (p = 0.013), while it increased mRNAs of sirtuin 1 (Sirt1) (p = 0.041) and peroxisome proliferator-activated receptor γ coactivator 1α (Pgc1α) (p = 0.017) over a shorter time course. Overall, our data suggest that vitamin-D-induced modulation of Fndc5/irisin occurs through up-regulation of Sirt1, which together with Pgc1α, is an important regulator of numerous metabolic processes in skeletal muscle. [ABSTRACT FROM AUTHOR]

Historical archives for the Roman Monarchic and Republican periods (753–29 BCE) offer a highly resolved series of observations of environmental and climatic phenomena in Central Italy. This paper presents a new collection of these historical archives, gathering 319 observations across the period. We introduce the historical character of these archives and point out aspects affecting their analysis and interpretation for reconstruction of past environmental and climatic conditions in Italy in the latter half of the first millenium BCE. Archival information is seen to be generally reliable from the fifth century BCE onward, providing a valuable source about regional past climate. The historical archives’ anecdotal nature along with complexities of their formation and transmission encourage cautious and closely contextualized interpretation, and we advocate the use of this information most of all to understand Romans’ changing experience of environment and climate. We offer comparison of this data to current understanding of regional climate conditions based on scientific proxies, especially speleothems and marine cores. These records show some convergence with the historical archives, and we discuss the possibility that this may reflect a relatively warm, wet climate period (Roman Warm Period) in Italy coterminous with Rome’s initial phase of imperial expansion. [ABSTRACT FROM AUTHOR]

Managing coastal development requires a set of tools to adequately detect ecosystem and water column degradation, but it also demands tools to detect any post-disturbance improvement. Structural seagrass indicators (such as shoot density or cover) are often used to detect or assess disturbances, but while they may be very sensitive to the impact itself, it is unclear if those indicators on their own can effectively reflect recovery at time scales relevant to managers. We used the construction of a harbour affecting a nearby Posidonia oceanica seagrass community to test the ability of a set of indicators (structural and others) to detect alterations and to evaluate their sensitivity to recovery of environmental quality after harbour construction was complete and the disturbance ceased. We used a Beyond Before After Control Impact (BBACI) design to evaluate effects on one impacted and three control meadows where we used structural, morphological, community and physiological indicators (26 in total) to asses disturbance impacts. Additionally, we measured some of the potential environmental factors that could be altered during and after the construction of the harbour and are critical to the survival of the seagrass meadow (light, sediment organic matter, sediment accrual). Harbour construction caused a clear increase in sediment organic matter and in sediment deposition rates, especially fine sand. Light availability was also reduced due to suspended sediments. Sediment and light conditions returned to normal levels 5 and 15 months after the construction began. As expected, seagrass structural indicators responded unequivocally to these environmental changes, with clear reductions in shoot density. Additionally, reduced light conditions quickly resulted in a decline in carbohydrate content in affected meadows. Unexpectedly, we also recorded a significant increase in metal content in plant tissues. No response was detected in the physiological indicators related to eutrophication (e.g. N and P content in tissues) and in morphological (shoot biomass) and community (epiphyte biomass) indicators. More than three years after the completion of the harbour, structural indicators did not show any sign of recovery. In contrast, physiological indicators, mainly heavy metal and carbohydrates content, were much better in detecting the improvement of the environmental conditions over the fairly short period of this study. These results indicate that while structural indicators are critical to evaluate the immediate effect of disturbances and the recovery on impacted systems, specific physiological indicators may be much better suited to determining the timing of environmental quality recovery. The design of impact and monitoring protocols in the wake of coastal developmental projects need to consider the differential effectiveness and time-response of measured indicators carefully. [ABSTRACT FROM AUTHOR]

The long-term fate of the blister agent sulfur mustard (HD, bis,(2-chloroethyl) sulfide) was determined in a variety of commercial and natural matrices. HD was found to he extremely stable in dry matrices for over a year. The addition of 5% water to the matrices induced slow degradation of HD, which lasted several months. The major degradation product in sands and asphalt was found to be a sulfonium salt, S[CH2CH2S+(CH2CH2OH)2]2 (H-2TG). Red loam soil, which has not been examined before, exhibited strong interaction with HD, both in dry form and in the presence of water, Humid red loam soil gave rise to unique oxidative degradation products. On humid concrete HD degraded to a complex mixture of products, including vinyls. This may be attributed to the basic sites incorporated in concrete. [ABSTRACT FROM AUTHOR]

The ammonium salt of monoethyloxalate (AmEtOx) was investigated as a novel precursor for the conservation of carbonate stone substrates, such as biomicritic limestone and marble. Full characterization of treated and untreated authentic stone samples was carried out by means of SEM, X-ray powder diffraction, synchrotron tts-μXRD measurements, mercury intrusion porosimetry, determination of water transport properties, and pull-off tests. The improved solubility (1.49 M, 20.1% w/w) of AmEtOx as compared to that of ammonium oxalate (AmOx; 0.4 M, 5% w/w) results in the formation of microcrystalline phases 30–50 and 200–500 μm thick of calcium oxalate mono-(whewellite) or dihydrate (weddellite), on marble and biomicrite samples, respectively, after treatment with AmEtOx 5% and 12% w/w aqueous solutions. As a result, a reduction in the porosity of the stone samples and an enhancement of their cohesion are observed. DFT calculations, carried out to investigate the hydrolysis reaction leading from AmEtOx to AmOx, showed that the localization of the Lowest Unoccupied Molecular Orbital (LUMO) and the natural charge distribution account nicely for the tendency to hydrolyse observed experimentally, eventually leading to the formation of whewellite and weddellite on the stone surface. [ABSTRACT FROM AUTHOR]

Characterizing the temporal uncertainty in palaeoclimate records is crucial for analysing past climate change, correlating climate events between records, assessing climate periodicities, identifying potential triggers and evaluating climate model simulations. The first global compilation of speleothem isotope records by the SISAL (Speleothem Isotope Synthesis and Analysis) working group showed that age model uncertainties are not systematically reported in the published literature, and these are only available for a limited number of records (ca. 15 %, n=107/691). To improve the usefulness of the SISAL database, we have (i) improved the database's spatio-temporal coverage and (ii) created new chronologies using seven different approaches for age–depth modelling. We have applied these alternative chronologies to the records from the first version of the SISAL database (SISALv1) and to new records compiled since the release of SISALv1. This paper documents the necessary changes in the structure of the SISAL database to accommodate the inclusion of the new age models and their uncertainties as well as the expansion of the database to include new records and the quality-control measures applied. This paper also documents the age–depth model approaches used to calculate the new chronologies. The updated version of the SISAL database (SISALv2) contains isotopic data from 691 speleothem records from 294 cave sites and new age–depth models, including age–depth temporal uncertainties for 512 speleothems. SISALv2 is available at 10.17864/1947.256 (Comas-Bru et al., 2020a). [ABSTRACT FROM AUTHOR]