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The surge in Distributed Denial of Service (DDoS) attacks within SDN environments demands more potent defense strategies. While Moving Target Defense (MTD) holds promise, current MTD approaches against DDoS suffer from security gaps due to overwhelming malicious traffic and static detection areas. In order to tackle these difficulties, we have implemented BSDN-HMTD, a combination of deep learning and blockchain technologies within SDN environments, as a framework. Our strategy starts by employing blockchain technology to authenticate users. We use the NTRU-based Nyberg Rueppel Digital Signature Algorithm for this purpose. This ensures that only authenticated user flows are allowed for validation and forwarding. Within the forwarding layer, Quantum Convolutional Neural Networks (QCNN) evaluate authentic flows by analyzing many characteristics, effectively differentiating between regular, malicious, and dubious flows. Utilizing an Enhanced Spotted Hyena Optimization (EHSO) method to activate switches in real-time modifies the vulnerable points of attack, so impeding attackers and simultaneously decreasing energy usage. The Forwarding Layer Organizer (FLO) oversees the detection of possible attacker surveillance activities and transmits the collected information to local controllers in the control layer. The controllers, functioning in a structured controller network, carry out proactive Moving Target Defense (MTD) techniques, such as host virtual IP hopping, which make attacker plans more complex and raise their operational expenses. Reactive MTD actions are implemented based on the results of flow validation. These actions utilize techniques such as secure honeypots and host virtual IP hopping to effectively prevent attacks. The blockchain securely logs all processed data related to packet validation, authentication, and honeypot activities to ensure the protection of data privacy. Our studies, conducted using Network Simulator-3.26 (NS-3.26), show that our proposed framework outperforms existing techniques in terms of several validation criteria.

The purification and characterization of lipopeptide biosurfactants produced by Bacillus sp. MI27 permits to identify two clusters of cyclic and linear surfactin isoforms. Aiming for a potential application in industrial biotechnology, we studied its potential washing capacity. The results show a good ability to wash oil stains, motor oil and mayonnaise evaluated by the determination of the % of stain removal and tissue bleaching indices after washing. Optimal washing capacities were unregistered for 300 and 400 mg/L at pH values ranging from 5 to 9 and temperatures ranging from 20 to 40°C. Using a 4-factor mixing design, we optimized a liquid formula composed only of BioS; silicate; carboxymethyl cellulose and calcium phosphate. The washing efficiency of the formula is of the order of 43.46% for petroleum and 49.10% for motor oil with a percentage reduction in surface tension of about 55.79% corresponding to 25.7 mN/m. HIGHLIGHTS Identification of cyclic and linear surfactin isoforms from Bacillus sp. MI27.; Optimal washing capacities for 300–400 mg/L at pH values 5–9 and temperatures 20–40 °C.; Mixture design for optimized liquid formula composed only of BioS, silicate, carboxymethyl cellulose and calcium phosphate.; The washing efficiency of the formula is 43.46% for petroleum and 49.10% for motor oil.; Surface tension value of 25.7 mN/m.;

Abstract This study is an attempt for comprehensive, combining experimental data with advanced analytical techniques and machine learning for a thorough understanding of the factors influencing the wear and cutting performance of multi-blade diamond disc cutters on granite blocks. A series of sawing experiments were performed to evaluate the wear and cutting performance of multi blade diamond disc cutters with varying diameters in the processing of large-sized granite blocks. The multi-layer diamond segments comprising the Iron (Fe) based metal matrix were brazed on the sawing blades. The segment’s wear was studied through micrographs and data obtained from the Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray (EDS). Granite rock samples of nine varieties were tested in the laboratory to determine the quantitative rock parameters. The contribution of individual rock parameters and their combined effects on wear and cutting performance of multi blade saw were correlated using statistical machine learning methods. Moreover, predictive models were developed to estimate the wear and cutting rate based on the most significant rock properties. The point load strength index, uniaxial compressive strength, and deformability, Cerchar abrasivity index, and Cerchar hardness index were found to be the significant variables affecting the sawing performance.

In this article, we present dielectric modulation-based label free detection of biomolecules at a cavity under gate metal located near the tunneling junction of charge plasma based dual metal-double gate tunnel FET (CP-DM DGTFET). The biomolecules that settle down in the cavity act as dielectric above the tunneling junction and cause drain current to increase/ decrease. To eliminate the short channel impact and to enhance ION/IOFF ratio without compromising any other device features, dual metal gate architecture with laterally split dielectric is used. The biosensor is capable of recognizing neutral, positive, and negative charges with the highest drain current sensitivity of $2.9\times 10 ^{9}$ Ccm-2 and highest ION/IOFF ratio of $9.02\times 10 ^{11}$ for biomolecule gelatin with dielectric constant k =12. This work explores the effectiveness of charge-plasma based DM DGTFET for detection of biomolecules such as gelatin (k =12), keratin (k =8), bacteriophage T7 (k =6.3), and APTES (k =3.57) with varied charge distribution at various biasing. The drain current sensitivity, subthreshold slope, drain current, ON/OFF current ratio are computed for various biomolecules and their variations with respect to cavity length, biomolecule charge, etc. are used to detect unknown biomolecules. Finally, RF analysis such as gain bandwidth product, cut-off frequency, transit time, and linearity/selectivity of biosensors are incorporated. The device shows better linearity and less distortion for high –k biomolecules. The results of our studies are reproducible for repeated computed analysis.

The device dimension down scaling beyond 14 nm technology node utilization of device architecture and new materials is a need of the semiconductors industry. In this paper, three materials, In $_{\mathrm {1-x}}$ GaxAs/ In $_{\mathrm {1-x}}$ GaxP, In $_{1-}$ xGax GAA JL FET developed and analyzed for their analog performance at high temperature. In $_{\mathrm {1-x}}$ GaxAs has a composition of 53% InAs and 47% GaAs with a band gap of 0.75 eV, whereas In $_{\mathrm {1-x}}$ GaxP and In $_{\mathrm {1-x}}$ GaxN exhibit a wider band gap of 1.90 eV and 3.2 eV, respectively, and exhibit different analog performance. An analytical model that is temperature-dependent for the drain current of In $_{\mathrm {1-x}}$ GaxAs, In $_{\mathrm {1-x}}$ GaxP, In $_{\mathrm {1-x}}$ GaxN GAA JL FET with mobility variations has also been developed. The ratio of transconductance-to-normalized drain current (gm/I $_{\mathrm {DS}}$ ) is utilized to examine analog properties. This ratio is a crucial measure of analog performance since it reveals the sensitivity and linearity of the device. All device parameters such as transconductance (g $_{\mathrm {m}}$ ), gm/IDS, cut-off frequency, and intrinsic gain were investigated for higher temperatures ranging from T =300 K to T =500 K. The newly developed device parameters have very low-temperature sensitivity, making these three material devices potential candidates for high temperature applications.

Abstract The Gulf of Trieste, is a shallow semi‐enclosed sea of about 500 km2 in the north‐eastern part of the Adriatic Sea. The coastal and marine areas of the Italian region Friuli Venezia Giulia, which borders most of the Gulf of Trieste, are subject to significant pressure from human activities, especially in terms of maritime traffic, ports, industry, fishing and tourism. But they are also characterised by natural areas of high environmental value. We wanted to understand the human impact on these coastal and marine areas in order to better inform sustainable management. To carry out the analysis, we collected a range of anthropogenic (human) and environmental data, from which we produced a series of indicator maps. By combining the various indicators, we created two subsequent maps: the seabed vulnerability map and the marine environment vulnerability map in the area as a whole. The analysis has highlighted areas with different degrees of environmental vulnerability due to human development and identified the most critical areas in the Gulf of Trieste with high anthropogenic pressure. Both maps show that human impacts affect large areas of the seabed and marine environment, while those with minimal or non‐existent impacts are very limited and are related mainly to areas with high levels of existing protection and conservation. The seabed vulnerability map shows that the biggest problems are related to discharge of dredging sludge, mollusc fishing with dredgers and turbo blowers, and anchoring boats. Furthermore, the presence of anthropogenic elements on the seabed can damage the natural environment and even permanently alter the natural shape and structure of the seabed. The marine environment vulnerability map shows that ports, urbanisation, industrial activities, maritime traffic and fishing pressure affect the entire study area. The vulnerability maps are a useful analytical tool to identify the most critical areas where possible actions can be planned to maintain a healthy and sustainable productive marine environment and to manage and resolve the conflicts between economic development and environmental health. Read the free Plain Language Summary for this article on the Journal blog.

Heavy metal pollution damages the ecosystems and presents a major problem for public health. Thus, an urgent need was developed to decrease the high levels of heavy metals in the soil and aquatic environments. With this aim, numerous physicochemical strategies were developed. However, they are money-consuming, require the use of energy and chemical additives and can release secondary compounds that can pollute and cause great damage to the environment. Then, biological methods based on the investigation of bacteria, fungi and plants along with their derived secondary active metabolites became the best alternatives. Using plant capacities, different phytoremediation strategies were developed such as phytoextraction, phytovolatilization, rhizofiltration and phytostabilization. Regarding bioremediation, bacterial biosorption of heavy metals, biolixiviation and lagooning offer great potential for their environmental cleaning. Additionally, the use of secondary active metabolites, such as biosurfactants, is well-studied. Generally, they are a class of structurally very varied molecules commonly synthesized by many microorganisms with amphiphilic character. Owing to their anionic charge, they have the capacity to sequestrate heavy metals permitting their elimination. Glycolipids and lipopeptides are among the most recognized biosurfactants with interesting heavy metal chelating properties. HIGHLIGHTS Studied heavy metal pollution and toxicology.; Bioremediation and phytoremediation technologies for heavy metal depollution.; Use of biosurfactants as heavy metal chelators.;

Background: Even though anti-neutrophil cytoplasmic antibodies (ANCA) are frequently linked to ANCA associated vasculitis (AAV), it's important to understand that other illnesses, including lung diseases, can also manifest as ANCA positivity. Finding the incriminated pathology might be difficult. Aim: To report four ANCA-associated cases with a diagnosis problem. Methods: Four patients were recruited from the allergo-pneumology department of the Fattouma Bourguiba University Hospital of Monastir, Tunisia, over two years (2020–2022). Indirect immunofluorescence technique on neutrophil cells (Euroimmun, Germany) was used for ANCA screening with a positivity limit of 1/20. ANCA typing was carried out by a line-blot technique (Euroimmun, Germany). Results: This case series reports four cases (age range: 41–67 years, sex ratio: 0.3) that presented with pulmonary manifestations associated with ANCA positivity. Two patients had perinuclear ANCA with anti-myeloperoxidase on typing, and two cases had cytoplasmic ANCA with one case of anti-leukocyte proteinase 3 on typing. Final diagnoses were pulmonary tuberculosis (case 1), systemic lupus erythematosus (case 2), bronchiolitis obliterans organizing pneumonia (case 3), and pulmonary aspergillosis with AAV (case 4). Conclusion: A panel of diagnoses may be evoked in front of positive ANCA, making the diagnosis difficult to determine and requiring multidisciplinary interactions, with imaging and histological investigations having a crucial role in guiding the final decision.

Thanks to their multifunctional properties, such as foaming, emulsifying and skin hydrating activities biosurfactants are potentially used in the cosmetic industry. In the present work, firstly, skin cream formulations using chemical surfactant agents and lipopeptide biosurfactants isolated from Bacillus subtilis SPB1 were investigated. The efficiency of the selected formula, containing 15% biosurfactant, was tested and its physicochemical properties were satisfying. In fact, it shows a spreading ability of 23 mm, a water activity of 0.72 and a pH value of 5. In addition, its biological activities were interesting showing a zone of inhibition against Gram-positive bacteria ranging from 8 to 15 mm. Moreover, it presents an antiradical effect against diphenyl-1-picrylhydrazyl (DPPH) with an IC50 of the order of 68 mg/mL. Second, seeking a highly stable SPB1 biosurfactant formulation for an easy commercial trend, a combination of biosurfactant, Gum Arabic (GA) and glycerol was optimized using the Box–Behnken (BB) design. As analysed, the model predicts an optimal value of the surface tension (ST) equal to 40.18 ± 0.39 mN/m when the respective values of the percentages of SPB1 BioS, glycerol and GA are equal to 72.62, 7.5 and 1.5%. Under these conditions, the emulsification index (EI)-24% is around 81.76 ± 0.14%. HIGHLIGHTS BioS-based formula has interesting biological and physicochemical properties.; A Box–Behnken design permits to optimize a BioS-based formula composed of 72.62% SPB1 BioS, 7.5% glycerol and 1.5% Gum Arabic.; The optimized formula has an EI-24% of 81.19 and reduces the ST of water to 41.4 mN/m.; The BioS-based formula can be incorporated into cosmetic products, preventing water pollution and ecological toxicity.;

Aiming the potential application of lipopeptide biosurfactant (BioS) in bioremediation, we studied its production by a novel, isolated strain of Bacillus sp. MI27. Using the experimental design methodology, a novel medium composed of 2% sucrose, 0.27% Na2HPO4, 0.2% ammonium sulfate, 0.02% NaCl, 0.02% CaCl2, 0.02% MgSO4, 0.001% MnSO4, 0.06% KH2PO4, 0.005% FeSO4 and 0.005% ZnSO4 was optimized. With this composition, strain MI27 produces 1.4 g/L BioS with maximum surface tension (ST) reduction of 23 mN/m and a dispersion diameter of around 10 cm. Emulsifying and foaming activities have been also confirmed. The critical micelle concentration (CMC) value was about 120 mg/L with corresponding ST of 23 mN/m. The dispersion and emulsification index (EI) were about 12 cm and 45% at 1,000 mg/L respectively. Moreover, the foaming capacity, stable over 1 h of incubation, was about 80% at 1,000 mg/L. Additionally, we studied the effect of different pH, temperature and salinities on MI27 BioS activity and stability. Obtained results showed interesting surface activities at extreme physicochemical conditions, especially at acidic and alkaline pH values, high and low temperatures and higher salinities. All these characteristics enable the possible application of BioS in water treatment biotechnology under diverse environmental conditions. HIGHLIGHTS Experimental methodology to optimize lipopeptide production by Bacillus sp. MI27.; Optimized medium composed only of sucrose, ammonium sulfate and mineral elements.; The lipopeptide had a CMC value of 120 mg/L with a surface tension of 23 mN/m. It disperses and emulsifies oil to about 12 cm and 45% with a foaming capacity of about 80%.; The lipopeptide showed surface activity and stability at extreme physicochemical conditions.;

The current work aims to optimize biological textile effluent treatment through the use of newly selected bacterial consortia composed of two strains: Citrobacter sedlakii RI11 and Aeromonas veronii GRI. We assessed the effect of SPB1 biosurfactant addition on color removal (CR). The process was optimized by a Box–Bhenken by examining the effect of pH, consortia density and biosurfactant value on treatment efficiency. Firstly, physicochemical analyses of the studied effluent revealed an alkaline pH along with a high content of suspended materials and large amounts of organic matter. Optimal CR and a chemical oxygen demand abatement of about 94 and 86% were obtained when treating the textile effluent at pH 5 with a total optical density of 0.4 and by incorporating 0.01% SPB1 biosurfactant. Additionally, an abolishment of phytotoxicity was registered after treatment optimization. The evaluations of the action mode of both selected bacteria during textile effluent treatment suggested the occurrence of biodegradation phenomena of dyes through enzymatic activities. HIGHLIGHTS Bacterial textile effluent treatment.; Optimization of the treatment by Box–Bhenken design and response surface methodology.; Optimal treatment by the increase of color removal and the abatement of chemical oxygen demand.; Enhancement of the treatment by SPB1 biosurfactant addition.;