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Effects of trench drain systems on pore water pressures in slow, deep, clayey landslides: Influence of hydraulic properties of the slip zone
No full textTrench drain systems are widely used as remedial measures for slow landslides in saturated fine-grained soils. Among the factors that influence their effectiveness, the hydraulic peculiarities of the slip zone have not been sufficiently investigated. This paper presents the results of numerical analyses of the effects of trench drain systems on clay slope models characterised by very low hydraulic conductivities of the landslide body (kl) and stable formation (kf), with the conductivity of the slip zone (ksz) being several orders of magnitude higher. The hydraulic models reproduced the conditions of a real landslide. Analyses were performed using the code SEEP3D. SEEP/W 2D and PLAXIS 2D were used for comparison. The 3D model shows that, as the ksz/kl ratio increases, the effectiveness of a drain system shallower than the slip surface significantly decreases. As an example, in the case of 12-m-deep trenches, a 25-m-deep slip surface, ksz = kl = 10-9 m/s, and kf = 10-10 m/s, the drains reduce the pore water pressure in the deepest points of the slip zone by approximately 100 kPa. Conversely, if ksz = 10-6 m/s, the pore pressure reduction is only about 10 kPa. Therefore, a drain system designed without considering the hydraulic peculiarities of the slip zone may not be effective. As the trench depth increases, drainage reduces the pore water pressure with a highly non-linear trend, exerting significant effects when the trenches reach the slip surface. Furthermore, 2D models may significantly overestimate the pore water pressure. The differences between the results of 2D and 3D models depend on the trench depth, hydraulic conductivity, and hydraulic boundary conditions
Possible accumulation of emerging contaminants of concern in treated wastewater on the soil plant system of a processing tomato-wheat succession
Get PDFTreated wastewater (TWW) is increasingly recognized as a valuable resource for agriculture and water management in the Mediterranean region. However, its use can pose significant risks due to the potential presence of
emerging contaminants of concern (ECCs), including personal care products, pesticides, food additives, and
pharmaceuticals. This study aimed to evaluate the impact of irrigation with TWW on the accumulation of ECCs
within the soil-plant system during a processing tomato (Solanum lycopersicum L.)-durum wheat (Triticum turgidum spp. durum) crop succession. The experiment was carried out on Petrocalcic Palexerolls soil. Over two
experimental years, both crops were irrigated using two water sources: TWW and freshwater (FW) as a control.
Of the 17 compounds detected in the TWW, only 8 were found in the soil (clarithromycin, carbamazepine,
fluconazole, climbazole, flecainide, sitagliptin, telmisartan and venlafaxine). The use of TWW effluent led to a
significant increase in the soil of carbamazepine up to 3.3 ± 0.5 ng g− 1
, sitagliptin up to 9.4 ± 0.4 ng g− 1
,
flecainide up to 8.3 ± 1.6 ng g− 1
, and clarithromycin up to 5.3 ± 0.6 ng g− 1
, highlighting their potential
accumulation during the two tomato-wheat cycles. Crop uptake varied depending on the specific ECC, with
different levels detected in plant roots, leaves, and stems. Importantly, no ECCs were detected in the edible parts
of either crop, with concentrations below the limit of quantification. These findings underscore the potential of
using TWW for irrigation without compromising food safety in crops like tomatoes and durum wheat. However,
continued monitoring and further research are essential to fully understand the long-term effects of ECCs on
agricultural systems and ensure the protection of both human health and the environment
Proton reconstruction with the TOTEM Roman pot detectors for high-β* LHC data
No full textThe TOTEM Roman pot detectors are used to reconstruct the transverse momentum of scattered protons and to estimate the transverse location of the primary interaction. This paper presents new methods of track reconstruction, measurements of strip-level detection efficiencies, cross-checks of the LHC beam optics, and detector alignment techniques, along with their application in the selection of signal collision events. The track reconstruction is performed by exploiting hit cluster information through a novel method using a common polygonal area in the intercept-slope plane. The technique is applied in the relative alignment of detector layers with μm precision. A tag-and-probe method is used to extract strip-level detection efficiencies. The alignment of the Roman pot system is performed through time-dependent adjustments, resulting in a position accuracy of 3 μm in the horizontal and 60 μm in the vertical directions. The goal is to provide an optimal reconstruction tool for central exclusive physics analyses based on the high-β∗ data-taking period at √s = 13 TeV in 2018
Methodological Approaches for Estimating the Biomass of Natural Pastures in the Lucanian Hills Using UAV Remote Sensing
No full textGrazing is essential for extensive farming; effective management faces challenges from competition between fodder and energy crops, land degradation, and the variability in yields due to climate change. The amount of biomass in pastures can significantly influence the number of livestock that can be supported. Nowadays, seasonal variability, sustainable pasture management, and animal feed requirements ask for a simple method to estimate the amount of available biomass. Using sensors, unmanned aerial vehicles (UAVs), and information technologies has streamlined farm management. Key parameters for assessing pasture quality and animal nutrition are dry matter (DM) and biomass. The project has two objec-tives: (i) to compare and evaluate two methods for assessing the natural pasture biomass; (ii) to calculate an equation to be applied to estimate the biomass of natural pastures using surveys made only by UAVs. In this paper, we focused on the first objective. The methods compared were pasture biomass monitoring using field sampling versus UAV surveys. Both methods were applied on the same day: the first more laborious and demanding, provided accurate vegetative data; the second proved to be a more effective approach for large-scale vegetation monitor-ing. Remote sensing was performed using a drone equipped with a multispectral camera. This approach is being used for the first time on natural Mediterranean pastures. Results indicated a significant and positive correlation between the two methods. These promising findings will be tested in the spring-summer period, and a calibration equation will be created to convert NDVI values into kg DM ha-1 of pasture
Fipronil in Agroecosystems: Impacts on Crop–Pest Dynamics and Sustainable Water Treatment through Biochar Regeneration
Get PDFThe increasing reliance on treated wastewater for agricultural irrigation introduces emerging contaminants such as fipronil into agroecosystems. This extended abstract synthesizes findings from two recent studies: one investigating the effects of fipronil-contaminated irrigation on zucchini plants and their primary pest, Aphis gossypii, and another exploring the use of forest-residue-derived biochar for the adsorption and regeneration of fipronil and other pollutants from water. Together, these studies highlight the dual challenge of mitigating environmental contamination while maintaining agricultural productivity and pest control efficacy
Enhanced relaxation dynamics in silver-doped chitosan nanocomposites: Probing the charge carrier dynamics and terahertz dielectric response
Get PDFThis study investigates the influence of silver nanoparticle incorporation on the electro-optical properties of chitosan, a biocompatible and versatile polymer with promising applications in biomedicine, energy storage, and sensing technologies, to name a few. Silver nanoparticles were synthesized by nanosecond laser ablation of the silver target in the polymeric solution. Terahertz time-domain spectroscopy was used to determine the complex dielectric function of pure chitosan and chitosan-silver nanocomposite films over a broad frequency range. The experimental data were analyzed using theoretical models, based on the Drude-Smith and Havriliak-Negami equations, to elucidate the underlying charge carrier dynamics and dielectric relaxation processes. Additionally, complex impedance and complex dielectric modulus analyses were conducted, incorporating Cole-Cole plots. The findings reveal a significant enhancement in the relaxation dynamics of the nanocomposite compared to pure chitosan, evidenced by a shift towards higher frequencies in the imaginary part of the dielectric function and a characteristic quarter-circle arc in the Cole-Cole plot. This study provides valuable insights into the structure-property relationships governing the electro-optical behavior of chitosan-based nanocomposites, paving the way for their tailored design and optimization for advanced technological applications
Search for light long-lived particles decaying to displaced jets in proton–proton collisions at sqrt{s} = 13.6 TeV
No full textA search for light long-lived particles (LLPs) decaying to displaced jets is presented, using a data sample of proton-proton collisions at a center-of-mass energy of 13.6 TeV, corresponding to an integrated luminosity of 34.7 fb-1, collected with the CMS detector at the CERN LHC in 2022. Novel trigger, reconstruction, and machine-learning techniques were developed for and employed in this search. After all selections, the observations are consistent with the background predictions. Limits are presented on the branching fraction of the Higgs boson to LLPs that subsequently decay to quark pairs or tau lepton pairs. An improvement by up to a factor of 10 is achieved over previous limits for models with LLP masses smaller than 60 GeV and proper decay lengths smaller than 1 m. The first constraints are placed on the fraternal twin Higgs (FTH) and folded supersymmetry (FSUSY) models, where the lower bounds on the top quark partner mass reach up to 350 GeV for the FTH model and 250 GeV for the FSUSY model
Determining the core bacterial and fungal genera in table olive fermentations
No full textTable olives are among the most ancient and important fermented foods of the Mediterranean basin. Their production is still strongly related to traditional practices, and the lack of thermal treatments, the reliance on natural contamination and selective factors (NaCl, pH, occurrence of phenolics, etc.) determine the dynamics of the microbial community. Lactic acid bacteria (LAB) and yeasts have a pivotal role in table olive microbial communities, but several halophilic and alkalophilic microorganisms may also contribute, positively or negatively, to the quality and safety of this fermented vegetable food. We have used metataxonomic data extracted from the FoodMicrobionet database to provide quantitative insights on the structure of bacterial and fungal microbial communities of table olives and to identify core genera in different trade preparations. Celerinatantimonas and Lactiplantibacillus were the most prevalent genera among bacteria, followed by several LAB, halophilic and alkalophilic lactic acid bacteria (HALAB) and Gram negatives, including non-halophilic species. Similarly, 3 fungal genera (Pichia, Candida, and Wickerhamomyces) were the most abundant and prevalent among fungi. The distribution of both bacteria and fungi varied significantly in different olive varieties, among olives, brines and contact surfaces or materials, and at different production stages, and no clear grouping related to the combination of ripeness and trade preparation was found, although HALAB were characteristically abundant in Spanish style green olives. Addition of starter cultures affected the composition and dynamics of microbial communities to a variable extent
Stairway to discovery: A report on the CMS programme of cross section measurements from millibarns to femtobarns
No full textThe Large Hadron Collider at CERN, delivering proton–proton collisions at much higher energies and far higher luminosities than previous machines, has enabled a comprehen-sive programme of measurements of the standard model (SM) processes by the CMS experiment. These unprecedented capabilities facilitate precise measurements of the properties of a wide array of processes, the most fundamental being cross sections. The discovery of the Higgs boson and the measurement of its mass became the keystone of the SM. Knowledge of the mass of the Higgs boson allows precision comparisons of the predictions of the SM with the corresponding measurements. These measurements span the range from one of the most copious SM processes, the total inelastic cross section for proton–proton interactions, to the rarest ones, such as Higgs boson pair production. They cover the production of Higgs bosons, top quarks, single and multibosons, and hadronic jets. Associated parameters, such as coupling constants, are also measured. These cross section measurements can be pictured as a descending stairway, on which the lowest steps represent the rarest processes allowed by the SM, some never seen before
Sondaggi e materiali sulla ricezione del «Cristo si è fermato a Eboli» di Carlo Levi (1946)
No full textThe success of Carlo Levi's novel was immediate and almost unanimous since its release: here we analyze and report some of the reviews from 1946 with particular attention to the writings of Gian Domenico Giagni, a profound expert of the Lucania poetic and its evo-cative image in those year