2,097 research outputs found

    On the Use of Google Earth Engine and Sentinel Data to Detect 'Lost' Sections of Ancient Roads. The Case of Via Appia

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    The currently available tools and services as open and free cloud resources to process big satellite data opened up a new frontier of possibilities and applications including archeological research. These new research opportunities also pose several challenges to be faced, as, for example, the data processing and interpretation. This letter is about the assessment of different methods and data sources to support a visual interpretation of EO imagery. Multitemporal Sentinel 1 and Sentinel 2 data sets have been processed to assess their capability in the detection of buried archeological remains related to some lost sections of the ancient Via Appia road (herein selected as case study). The very subtle and nonpermanent features linked to buried archeological remains can be captured using multitemporal (intra- and inter-year) satellite acquisitions, but this requires strong hardware infrastructures or cloud facilities, today also available as open and free tools as Google Earth Engine (GEE). In this study, a total of 2948 Sentinel 1 and 743 Sentinel 2 images were selected (from February 2017 to August 2020) and processed using GEE to enhance and unveil archeological features. Outputs obtained from both Sentinel 1 and Sentinel 2 have been successfully compared with in situ analysis and high-resolution Google Earth images

    Insulin Resistance and Body Fat Distribution in South Asian Men Compared to Caucasian Men

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    South Asians are susceptible to insulin resistance even without obesity. We examined the characteristics of body fat content, distribution and function in South Asian men and their relationships to insulin resistance compared to Caucasians.Twenty-nine South Asian and 18 Caucasian non-diabetic men (age 27+/-3 and 27+/-3 years, respectively) underwent euglycemic-hyperinsulinemic clamp for insulin sensitivity, underwater weighing for total body fat, MRI of entire abdomen for intraperitoneal (IP) and subcutaneous abdominal (SA) fat and biopsy of SA fat for adipocyte size.Compared to Caucasians, in spite of similar BMI, South Asians had higher total body fat (22+/-6 and 15+/-4% of body weight; p-value<0.0001), higher SA fat (3.5+/-1.9 and 2.2+/-1.3 kg, respectively; p-value = 0.004), but no differences in IP fat (1.0+/-0.5 and 1.0+/-0.7 kg, respectively; p-value = 0.4). SA adipocyte cell size was significantly higher in South Asians (3491+/-1393 and 1648+/-864 microm2; p-value = 0.0001) and was inversely correlated with both glucose disposal rate (r-value = -0.57; p-value = 0.0008) and plasma adiponectin concentrations (r-value = -0.71; p-value<0.0001). Adipocyte size differences persisted even when SA was matched between South Asians and Caucasians.Insulin resistance in young South Asian men can be observed even without increase in IP fat mass and is related to large SA adipocytes size. Hence ethnic excess in insulin resistance in South Asians appears to be related more to excess truncal fat and dysfunctional adipose tissue than to excess visceral fat

    SAR Sentinel 1 imaging and detection of palaeo-landscape features in the mediterranean area

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    The use of satellite radar in landscape archaeology offers great potential for manifold applications, such as the detection of ancient landscape features and anthropogenic transformations. Compared to optical data, the use and interpretation of radar imaging for archaeological investigations is more complex, due to many reasons including that: (i) ancient landscape features and anthropogenic transformations provide subtle signals, which are (ii) often covered by noise; and, (iii) only detectable in specific soil characteristics, moisture content, vegetation phenomenology, and meteorological parameters. In this paper, we assessed the capability of SAR Sentinel 1 in the imaging and detection of palaeo-landscape features in the Mediterranean area of Tavoliere delle Puglie. For the purpose of our investigations, a significant test site (larger than 200 km2) was selected in the Foggia Province (South of Italy) as this area has been characterized for millennia by human frequentation starting from (at least) the Neolithic. The results from the Sentinel 1 (S-1) data were successfully compared with independent data sets, and the comparison clearly showed an excellent match between the S-1 based outputs and ancient anthropogenic transformations and landscape features

    Heat-killed probiotic bacteria differentially regulate colonic epithelial cell production of human β-defensin-2: dependence on inflammatory cytokines.

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    The inducible antimicrobial peptide human β-defensin-2 (hBD-2) stimulated by pro-inflammatory cytokines and bacterial products is essential to antipathogen responses of gut epithelial cells. Commensal and probiotic bacteria can augment such mucosal defences. Probiotic use in the treatment of inflammatory bowel disease, however, may have adverse effects, boosting inflammatory responses. The aim of this investigation was to determine the effect of selected probiotic strains on hBD-2 production by epithelial cells induced by pathologically relevant pro-inflammatory cytokines and the role of cytokine modulators in controlling hBD-2. Caco-2 colonic intestinal epithelial cells were pre-incubated with heat-killed probiotics, i.e. Lactobacillus casei strain Shirota (LcS) or Lactobacillus fermentum strain MS15 (LF), followed by stimulation of hBD-2 by interleukin (IL)-1β and tumour necrosis factor alpha (TNF-α) in the absence or presence of exogenous IL-10 or anti-IL-10 neutralising antibody. Cytokines and hBD-2 mRNA and protein were analysed by real-time quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. LcS augmented IL-1β-induced hBD-2, whereas LF enhanced TNF-α- and suppressed IL-1β-induced hBD-2. LF enhanced TNF-α-induced TNF-α and suppressed IL-10, whereas augmented IL-1β-induced IL-10. LcS upregulated IL-1β-induced TNF-α mRNA and suppressed IL-10. Endogenous IL-10 differentially regulated hBD-2; neutralisation of IL-10 augmented TNF-α- and suppressed IL-1β-induced hBD-2. Exogenous IL-10, however, suppressed both TNF-α- and IL-1β-induced hBD-2; LcS partially rescued suppression in TNF-α- and IL-1β-stimulation, whereas LF further suppressed IL-1β-induced hBD-2. It can be concluded that probiotic strains differentially regulate hBD-2 mRNA expression and protein secretion, modulation being dictated by inflammatory stimulus and resulting cytokine environment

    Google earth engine as multi-sensor open-source tool for supporting the preservation of archaeological areas: The case study of flood and fire mapping in metaponto, italy

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    In recent years, the impact of Climate change, anthropogenic and natural hazards (such as earthquakes, landslides, floods, tsunamis, fires) has dramatically increased and adversely affected modern and past human buildings including outstanding cultural properties and UNESCO heritage sites. Research about protection/monitoring of cultural heritage is crucial to preserve our cultural properties and (with them also) our history and identity. This paper is focused on the use of the open-source Google Earth Engine tool herein used to analyze flood and fire events which affected the area of Metaponto (southern Italy), near the homonymous Greek-Roman archaeological site. The use of the Google Earth Engine has allowed the supervised and unsupervised classification of areas affected by flooding (2013–2020) and fire (2017) in the past years, obtaining remarkable results and useful information for setting up strategies to mitigate damage and support the preservation of areas and landscape rich in cultural and natural heritage

    Grazing Impacts on Rangeland Condition in Semi-Arid South-Western Africa

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    The savannah biome, consisting of a dense herbaceous layer and a relatively open woody layer in competitive balance, constitutes 64% of the land surface of Namibia, an arid country in south-western Africa, and is used mainly for extensive cattle and sheep ranching. About half of the savannah area is affected by dense to moderately dense bush-thickening, resulting in a ten-fold decrease in the rangeland’s grass-based carrying capacity and a concomitant loss in meat production of about US$115 million per year (De Klerk, 2004). Bushencroached areas typically have densities \u3e 2 000 bushes/ha with \u3e 90% belonging to a single species. High grazing pressure by specialist grazers, such as domestic cattle, is often blamed for rangeland degradation. There is an urgent need to understand the dynamics of bush encroachment and devise grazing strategies to contain it

    Modeling the impact of climate change on the hydrology of Andasa watershed

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    This paper was aimed to study the impact of climate change on the hydrology of Andasa watershed for the period 2013–2099. The soil and water assessment tool (SWAT) was calibrated and validated, and thereby used to study the impact of climate change on the water balance. The future climate change scenarios were developed using future climate outputs from the Hadley Center Climate Model version 3 (HadCM3) A2 (high) and B2 (low) emission scenarios and Canadian Earth System Model version 2 (CanESM2) Representative concentration pathways (RCP) 4.5 and 8.5 scenarios. The large-scale maximum/minimum temperature and rainfall data were downscaled to fine-scale resolution using the Statistical Downscaling Model (SDSM). The mean monthly temperature projection of the four scenarios indicated an increase by a range of 0.4–8.5 °C while the mean monthly rainfall showed both a decrease of up to 97% and an increase of up to 109%. The long-term mean of all the scenarios indicated an increasing temperature and decreasing rainfall trends. Simulations showed that climate change may cause substantial impacts in the hydrology of the watershed by increasing the potential evapotranspiration (PET) by 4.4–17.3% and decreasing streamflow and soil water by 48.8–95.6% and 12.7–76.8%, respectively. The findings suggested that climate change may cause moisture-constrained environments in the watershed, which may impact agricultural activities in the watershed. Appropriate agricultural water management interventions should be implemented to mitigate and adapt to the plausible impacts of climate change by conserving soil moisture and reducing evapotranspiration

    Distribution-based bisimulation for labelled Markov processes

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    In this paper we propose a (sub)distribution-based bisimulation for labelled Markov processes and compare it with earlier definitions of state and event bisimulation, which both only compare states. In contrast to those state-based bisimulations, our distribution bisimulation is weaker, but corresponds more closely to linear properties. We construct a logic and a metric to describe our distribution bisimulation and discuss linearity, continuity and compositional properties.Comment: Accepted by FORMATS 201

    Integrated use of multi-temporal multi-sensor and multiscale Remote Sensing data for the understanding of archaeological contexts: the case study of Metaponto, Basilicata

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    This paper is focused on the archaeological area of Metaponto (Μεταπόντιον) and its territory, located in southern Italy. The area played an important role for the agricultural economy and the traffic of goods and people, from the south of Italy towards the central regions, starting from the Neolithic period, and reaching the zenith with the Greek polis of Metaponto and its hinterland. The site is herein analyzed through an integrated use of several Earth observation and remote sensing technologies and ancillary data produced over the years by archaeologists and scholars. The aim was to identify new buried elements of archaeological interest, for the reconstruction of the historical-archaeological landscape. Through the combined use of optical and radar satellite images, high-resolution images obtained by Unmanned Aerial System (visible, multispectral, and thermal infrared), geophysical data, and archival data, it was possible to deepen the knowledge of the area, in particular the “Castrum” area, identifying new buried evidence (structures, roads, and elements of the ancient landscape)

    Probabilistic Timed Automata with Clock-Dependent Probabilities

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    Probabilistic timed automata are classical timed automata extended with discrete probability distributions over edges. We introduce clock-dependent probabilistic timed automata, a variant of probabilistic timed automata in which transition probabilities can depend linearly on clock values. Clock-dependent probabilistic timed automata allow the modelling of a continuous relationship between time passage and the likelihood of system events. We show that the problem of deciding whether the maximum probability of reaching a certain location is above a threshold is undecidable for clock-dependent probabilistic timed automata. On the other hand, we show that the maximum and minimum probability of reaching a certain location in clock-dependent probabilistic timed automata can be approximated using a region-graph-based approach.Comment: Full version of a paper published at RP 201
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