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Impurity study in the dimensionless and dimensional isotope identity experiment between JET Deuterium and Tritium L-mode plasmas
No full textThe behaviour of impurities in fusion plasmas is of crucial importance for achieving sustained fusion reactions, and understanding similarities and differences between Deuterium (D) and Tritium (T) plasmas is needed to assess potential changes from DD to DT in ITER and future reactors. The first dimensionless and dimensional isotope identity experiments between Deuterium (D) and Tritium (T) L-mode plasmas were conducted at the JET W/Be wall. In the first approach, the discharges with matched ρ∗, ν∗, βn, q, and Te/Ti were compared to emphasize direct isotope effects, while in the dimensional approach engineering parameters such as toroidal magnetic field BT, plasma current Ip, plasma electron density and NBI power PNBI were matched. The dimensionless isotope scaling showed an improvement in global confinement and local transport in T plasmas in comparison to the matched D one (Cordey et al 1999 Nucl. Fusion 39 301). Detailed impurity analyses using VUV, visible spectroscopy, SXR cameras, and bolometry revealed that T plasmas exhibited higher radiation and impurity content, particularly Ni and W, compared to D plasmas. Understanding the origin of the increased impurity content is addressed in this paper. The dimensionless experiments showed differences in impurity transport. The Be source behaviour varied: D plasmas had higher Be influx in the dimensionless approach due to lower electron density and enhanced sputtering (Saibene et al 1999 Nucl. Fusion 39 1133), while T plasmas showed a higher Be source in the dimensional experiments, highlighting isotope mass effects. W in the divertor region was not sputtered by hydrogen isotopes. W in the divertor region was not sputtered by hydrogen isotopes. In the dimensionless experiments, W sputtering was primarily influenced by Ni in T plasmas and by Be in D plasmas. However, in the dimensional approach, Be played a more significant role in W sputtering within T plasmas. MHD instabilities, including ST oscillations, were present in all cases other ones were correlated with NBI power levels; higher NBI power led to elevated levels of Be, Ni, and W impurities. The comprehensive comparison underscores the necessity of accounting for isotope mass effects in predictive modelling and optimization of plasma performance in fusion reactors
Evaluation of the Soil Conservation Service Curve Number (SCS-CN) Method for Flash Flood Runoff Estimation in Arid Regions: A Case Study of Central Eastern Desert, Egypt
Get PDFFlash floods are highly destructive natural disasters, particularly in arid and semi-arid regions like Egypt, where data scarcity poses significant challenges for analysis. This study focuses on the Wadi Al-Barud basin in Egypt’s Central Eastern Desert (CED), where a severe flash flood occurred on 26–27 October 2016. This flash flood event, characterized by moderate rainfall (16.4 mm/day) and a total volume of 8.85 × 106 m3, caused minor infrastructure damage, with 78.4% of the rainfall occurring within 6 h. A significant portion of floodwaters was stored in dam reservoirs, reducing downstream impacts. Multi-source data, including Landsat 8 OLI imagery, ALOS-PALSAR radar data, Global Precipitation Measurements—Integrated Multi-satellite Retrievals for Final Run (GPM-FR) precipitation data, geologic maps, field measurements, and Triangulated Irregular Networks (TINs), were integrated to analyze the flash flood event. The Soil Conservation Service Curve Number (SCS-CN) method integrated with several hydrologic models, including the Hydrologic Modelling System (HEC-HMS), Soil and Water Assessment Tool (SWAT), and European Hydrological System Model (MIKE-SHE), was applied to evaluate flood forecasting, watershed management, and runoff estimation, with results cross-validated using TIN-derived DEMs, field measurements, and Landsat 8 imagery. The SCS-CN method proved effective, with percentage differences of 5.4% and 11.7% for reservoirs 1 and 3, respectively. High-resolution GPM-FR rainfall data and ALOS-derived soil texture mapping were particularly valuable for flash flood analysis in data-scarce regions. The study concluded that the existing protection plan is sufficient for 25- and 50-year return periods but inadequate for 100-year events, especially under climate change. Recommendations include constructing additional reservoirs (0.25 × 106 m3 and 1 × 106 m3) along Wadi Kahlah and Al-Barud Delta, reinforcing the Safaga–Qena highway, and building protective barriers to divert floodwaters. The methodology is applicable to similar flash flood events globally, and advancements in geomatics and datasets will enhance future flood prediction and management
Earlywood vessel characteristics are early indicators of drought-induced decline in ring-porous oak species within the Mediterranean Basin
Get PDFModulation of NCX1 expression in monocytes associates with multiple sclerosis progression
Get PDF: Ionic imbalance and functional heterogeneity of monocytes play key roles in multiple sclerosis (MS) progression. A better understanding of monocyte response in the context of ionic dysregulation during MS course may have relevant implications for understanding of disease pathogenesis and treatments. The sodium calcium exchanger NCX1 influences monocyte-derived macrophages reactivity under inflammation; however, little is known about its monocyte-specific expression during MS course. By means of RT-PCR, flow cytometry, and confocal analyses, we determined the expression profiling of NCX1 exchanger in monocytes of patients during relapsing-remitting MS (RRMS) and secondary progressive MS (SPMS) course. NCX1 expression was significantly upregulated in monocytes from transitional RRMS subjects. Conversely, it was significantly reduced in all monocyte subsets after RRMS conversion to SPMS. Interestingly, NCX1 levels in monocytes significantly correlated with the percentage and growth ability of the regulatory T cell (Treg) subset, whose derangement underlies MS progression. Perturbation of transcripts encoding the Ca2+-ATPase isoform 1 and 4, the Na+/K+-ATPase α1 subunit, and the long non-coding RNA SLC8A1-AS1 associated with NCX1 changes in peripheral blood mononuclear cells (PBMC) during MS. Our findings demonstrated a stage-specific dysregulation of NCX1 exchanger in monocytes during MS progression and suggested that ionic imbalance in monocytes may influence not only their functional response but also the immune regulatory network during MS course. These data may be relevant for the identification of novel biomarkers and/or therapeutic targets in MS
Individuazione e monitoraggio di siti idonei in aree interne per la creazione di una rete FER da mini- e micro-idroelettrico esempi dall’Italia meridionale e dal Portogallo.
No full textThis thesis aims to investigate and identify suitable river sections for the installation of mini- and micro-hydroelectric plants, capable of generating an interconnected energy system, and to evaluate their technical feasibility, economic sustainability, technological aspects, and environmental impact. The preliminary identification of suitable sites was based on both geographic-anthropogenic and geographic-physical characteristics. The selected sites are located within the Bradano River basin and the Noce River basin in Southern Italy, and the Mondego River basin in Portugal. Methodologies such as statistical and geomorphological analysis, photointerpretation, field surveys, quantitative geomorphic analysis of hydrological networks, and drone-based photogrammetry were employed to assess the rivers' potential for hydroelectric generation. These investigations are crucial for evaluating seasonal variations in river flows and conducting hydraulic calculations necessary for simulating sediment transport and mobile bed dynamics.
The thesis demonstrates that the creation and management of an integrated Renewable Energy (RE) network, including dispersed mini- and micro-hydroelectric plants, require detailed geomorphological and physical-geographical studies. Such studies are necessary to assess the geomorphic stability of drainage segments and identify potential hydraulic jumps, knickpoints, and other flow acceleration indicators. The research focuses on areas with low human density and minimal economic activity, typical of "inner areas" in southern Italy and rural Portugal, where the development of small-scale hydroelectric plants could contribute to regional development and energy independence.
The investigation of the three selected sites reveals distinct physical and lithological characteristics. The Bradano River basin, characterized by erodible marl and sandstone formations, and the Noce River basin, with its resistant Mesozoic limestone and unstable slopes, present suitable conditions for hydroelectric generation. The Mondego River basin in Portugal, though less expansive, also offers potential for micro-hydroelectric plants. The study recommends the establishment of interconnected RE networks to address seasonal flow issues and ensure a stable energy supply. Furthermore, continuous monitoring and hydraulic assessments are essential for ensuring ecological sustainability and compliance with environmental regulations, such as the maintenance of the minimum vital flow (DMV) and the protection of local biocenoses
A trade-based Forest Club as a path to halting Tropical deforestation
No full textDeforestation is a critical global issue that urgently requires action to prevent irreversible environmental damage. Although the European Union has recently introduced regulations to curb tropical deforestation linked to imports, our analysis, which combines geospatial and economic tools, shows that these measures address only a fraction of the global problem (protecting only around 58,000 hectares of tropical forest annually) and shift forest loss to temperate regions while imposing significant costs on tropical, forest‐rich nations. To explore the potential of broader international cooperation to limit deforestation, we employ a global trade model, building an iterative game-theoretic approach integrating land-use dynamics across different ecological zones7. Here we show that adopting a Forest Club approach, inspired by the "Climate Clubs"8 concept, can effectively reduce tropical deforestation. By initiating unilateral efforts, analyzing deforestation at local levels, and implementing appropriate economic incentives and trade-related financial mechanisms, it is possible to form a cooperative group that attracts more countries over time. Our findings demonstrate the feasibility of establishing a globally stable Forest Club that could significantly reduce global deforestation—by up to 15 million hectares—without imposing undue economic burdens. This highlights how well‐designed tariffs and negotiations can spark a stable, collective response to tropical forest loss worldwide
A Standardized Framework to Estimate Drought-Induced Vulnerability and Its Temporal Variation in Woody Plants Based on Growth
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