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This paper sheds the light on the future of green hydrogen in Tunisia. So, a detailed economic assessment and evaluation of the Levelized Hydrogen Cost (LHC) and the Net Profit (NP) of a Photovoltaic (PV) Hydrogen Refueling Station (HRS) are presented and discussed. Tunisia is characterized by its high PV potential which makes the production of electricity from solar energy an effective alternative source. However, due to the regulations and issues related to the connection of medium PV scale to the power grid, the energy produced from renewable sources (RS) is still less than 3% of the total produced electricity. On the other hand, the price of hydrocarbon fuels is still increasing. The gap between production and total demand in hydrocarbons has created a deficit in the primary energy balance. Therefore, the production of hydrogen from solar energy for refueling Fuel Cell Vehicles (FCV)s consists of a promising solution to boost the development of the country, reduce hydrocarbon fuels consumption, and protect the environment. The sizing of a small PV-HRS to produce 150 kg of hydrogen per day shows the necessity to install PV systems with a total Direct Current (DC) capacity of 1.89 MWp. The Initial Cost (IC) analysis shows that while the PV system cost represents 48.5% of the total IC, the IC of electrolysers represents 41%. The storage system cost is approximately equal to 3.2% of the total IC. The LHC is equal to 3.32€/kg with a total IC of 2.34 million €.

The present article aims to assess the phytotoxic effects of copper and zinc oxide nanoparticles (Cu NPs, ZnO NPs) on mung bean (Vigna radiata L.) and their possible risk on food quality and safety. We also study the molecular mechanisms underlying the toxicity of nanosized Cu and ZnO. Seeds of mung bean were germinated under increasing concentrations of Cu NPs and ZnO NPs (10, 100, 1000, 2000 mg/L). We analyzed levels of free amino acids, total soluble sugars, minerals, polyphenols and antioxidant capacity. Our results showed that depending on the concentrations used of Cu NPs and ZnO NPs, the physiology of seed germination and embryo growth were modified. Both free metal ions and nanoparticles themselves may impact plant cellular and physiological processes. At 10 mg/L, an improvement of the nutritive properties, in terms of content in free amino acids, total soluble sugars, essential minerals, antioxidant polyphenols and flavonoids, was shown. However, higher concentrations (100-2000 mg/L) caused an alteration in the nutritional balance, which was revealed by the decrease in contents and quality of phenolic compounds, macronutrients (Na, Mg, Ca) and micronutrients (Cu, Fe, Mn, Zn, K). The overall effects of Cu and ZnO nanoparticles seem to interfere with the bioavailability of mineral and organic nutrients and alter the beneficial properties of the antioxidant phytochemicals, mineral compounds, phenolic acids and flavonoids. This may result in a potential hazard to human food and health, at some critical doses of nanofertilizers. This study may contribute in the guidelines to the safe use of nanofertilizers or nanosafety, for more health benefit and less potential risks.

Hydrogen is a clean energy and has many applications in petroleum refining, glass purification, pharmaceuticals, semiconductors, aerospace applications and cooling generators. Therefore, it is very important to store it in various ways. One of the new and cheap methods to store hydrogen is storing in the brine groundwater. In this method, the hydrogen gas is injected into the brine, in which storing capacity has a direct relationship with the pressure, temperature and salt concentration of the saltwater. In the present study, an artificial neural network (ANN) was used to estimate and optimize the hydrogen solubility (HS) in the saltwater with conventional best algorithms such as the feedback propagation, genetic algorithm (GA) and radial basis function. The optimization is implemented based on available experimental data bank based on the variation of the pressure, working temperature and salt concentration. The results and assessments of different optimization ANN algorithm show that the GA has the most usable and accurate estimation and prediction for HS in the saltwater. Also, the amounts of the relevancy coefficient (${R}_c$) that correspond to the sensitivity of HS on the input parameters demonstrate that the salt concentration and pressure have the minimum and maximum ${R}_c$, respectively. That is, the least and most effect on the output values.

In this paper we present our calculation of the ionization cross section by electron impact of C V, N VI, and O VII. Using the Flexible Atomic Code (FAC), we obtain the cross sections for the ionization of these ions from the ground state 11S, and from the unstable states 21S and 23S. Our results are in good agreement with those based on the Coulomb–Born (CB) approximation and the available measurements.

Long-term time-series are a fundamental prerequisite to understand and detect climate shifts and trends. Understanding the complex interplay of changing ocean variables and the biological implication for marine ecosystems requires extensive data collection for monitoring and hypothesis testing and validation of modelling products. In marginal seas, such as Mediterranean Sea, there are still monitoring gaps, both in time and in space. To contribute filling these gaps, an extensive dataset of dissolved inorganic nutrients profiles (nitrate, NO3; phosphate, PO43−; and silicate, SiO2) have been collected between 2004 and 2017 in the Western Mediterranean Sea and subjected to quality control techniques to provide to the scientific community a publicly available, long-term, quality controlled, internally consistent biogeochemical data product. The database includes 870 stations of dissolved inorganic nutrients sampled during 24 cruises, including temperature and salinity. Details of the quality control (primary and secondary quality control) applied are reported. The data are available in PANGAEA (https://doi.org/10.1594/PANGAEA.904172, Belgacem et al. 2019).

Long-term protection of arid ecosystems changes the vegetation and soil structures. The quantification of aboveground biomass and carbon content are among the principal indicators to evaluate these...

Nanostructured PdO materials with promising catalytic properties were successfully synthesized by the controlled thermal decomposition in air of three Pd(II) complexes containing Pd(II) ion, ofloxacin drug and amino acid. The Pd(II) complexes which were used as precursors were [Pd(OFL)(Gly)]Cl, [Pd(OFL)(Ala)]Cl, and [Pd(OFL)2]Cl2, where Gly is glycine amino acid, Ala is alanine amino acid, and OFL is ofloxacin. Structural and morphological properties of the synthesized PdO materials were obtained using FTIR, XRD, SEM, and EDX techniques. The XRD results confirm the tetragonal structure of PdO. The obtained PdO materials were tested as a catalyst for the heterogeneous degradation of H2O2 solution. The results revealed that PdO could effectively degrade H2O2. KEY WORDS: PdO, Nanoparticles, Photocatalytic efficiency, Wastewater treatment Bull. Chem. Soc. Ethiop. 2021, 35(1), 107-118. DOI: https://dx.doi.org/10.4314/bcse.v35i1.9

Nanofibrilated cellulose (NFC) films have potential to replace synthetic polymers as flexible films for packaging. However, NFC is hydrophilic and water acts as plasticizer decreasing the stiffness of the films and reducing its barrier effectiveness against water vapor and oxygen. Here we describe the surface modification of cellulose films with blocked diisocyanates through a dipping and heating process not requiring the previous drying of the materials. The reactions were conducted at 170 °C for a few minutes during which deblocking led to a new urethane bond formation with NFC surface hydroxyl groups, thus hydrophobizing the films. A remarkable enhancement in water repellent properties was confirmed by water contact angles higher than 110° and water vapor transmission rate (WVTR) of 40 g/m2 day, which is very low when compared to similar materials, representing a reduction of 74% with respect to the non- modified films.

International audience

Fumonisin B1 (FB1) is a prevelant mycotoxin in our alimentary chain. It was produced by the fungi of the genus Fusarium verticillioides and Fusarium proliferatum. FB1 was playing as a competitive inhibitor of ceramide synthase; a key enzyme in the biosynthesis of sphingolipids. Indeed, it was associated with several affects in humans and livestock animals. The aim of our report was elucidated to evaluate the protective effects of Lactobacillus paracasei BEJ01 (LP) isolated from the traditional butter of Tunisia against the FB1 genotoxicity, hematoxicity, oxidative stress and histological damage in liver and kidney of BALB/c mice. Forty old week mice were randomly divided into four treatment groups (10 mice/group): Group 1: control; Group 2: LP (2 × 109 CFU/ml ~ 2 mg/kg p.c); Group 3: FB1 (100 μg/kg p.c.); Group 4: LP (2 × 109 CFU/ml ~ 2 mg/kg p.c) + FB1 (100 μg/kg p.c.). 48 h after the end of the treatment (10 days), the mice were sacrificed and the blood, liver and kidney were collected. The blood was used for hematological and biochemical studies. Liver and kidney samples were the target for evaluation of oxidative stress enzymes status and histopathological damage. The results indicated that FB1 was induced toxicities in the blood parameters and in liver and kidney tissues as well as in the profile of oxidative stress enzymes levels. The co-treatment with LP was found able to mitigate the FB1 toxicities by reduction of its bioavailability in the gastro intestinal tract. However, treatment with LP alone was safe and no sign of toxicity was showed. In Summary, the LP strain was able to prevent FB1 toxicities and indeed it could be exploited as one of the biological strategies for foodstuffs decontamination.

Recently, higher contamination by aflatoxin M1 (AFM1) has been detected in many countries. Unfortunately, many tons of contaminated milk and milk byproducts are removed from the food chain to avoid human contamination; as a consequence of higher economic losses. Fewest number of studies are interested to AFM1 detoxification using lactic acid bacteria.In this study, AFM1-degradation usingLPBEJ01 was safe and it did not have any sign of toxicity. It can be used as an additive for AFM1-detoxification contamination in the food chain in countries suffering from this problem.

In the current context, the development of bio-based and high-performance materials is one of the main research priorities. This study aims to combine the outstanding properties of cellulose nanofibrils (CNFs) or nanocrystals (CNCs) with those of bio-based poly(lactic acid) (PLA). Three-phase multilayered materials (TMLs) were built up by complexing a dry CNF- or CNC-based film with two PLA sheets, using a heat-pressing process. Before the preparation of the nanocellulosic films, CNFs and CNCs were modified by the adsorption of a rosin-based nanoemulsion. The rosin mixture as a natural compound is of interest because of its low cost, renewability, hydrophobicity, and its antimicrobial and antioxidant properties. After demonstrating the efficiency of the complexing procedure, we investigated the barrier properties of the multilayered materials against both oxygen and water vapor, with highly encouraging results. In fact, the presence of nanocellulose as an inner layer between the two PLA films significantly enhanced the oxygen barrier, with a decrease in oxygen permeability comprised between 84 and 96% and between 44 and 50% for neat nanocelluloses and nanocelluloses with rosins as the inner layer, respectively. On the other hand, the antioxidant properties of the final multilayered materials including rosins were highlighted, with a highly encouraging radical scavenging activity close to 20%. Because of the simplicity and the efficiency of the proposed method, this study paves the way toward the development of hybrid multimaterials that could be highly attractive for food packaging applications.

The biocompatibility and very high specific area of cellulose nanofibrils (CNF) are properties of high interest for the development of active substrates for new medical device development. Enzyme pretreated CNF (CNF-e) can be self-organized into nanostructured membranes that are suitable for active principle ingredients (API) encapsulation through adsorption phenomena. In addition, tunable surface chemistry of CNF-e, allow for covalent immobilization of API. In this work, ciprofloxacin is integrated to CNF-e membranes according to two different strategies. The first one relies only on adsorption mechanisms; ciprofloxacin is encapsulated in the bulk before the membrane formation by solvent casting. The influence of the membrane properties and preparation parameters such as grammage, thickness and drying technique, are assessed with water uptake measurements and API release experiments. The second strategy deals with the covalent immobilization of ciprofloxacin directly onto CNF-e membrane. The two kinds of membranes are then compared in terms of antibacterial activity, in both static and dynamic conditions. Thick CNF-e membranes loaded with adsorbed ciprofloxacin that were overdried (2 h, 150 °C) prove to be more resistant in liquid medium and present a more prolonged drug release. However, these membranes rapidly lost their antibacterial activity, while CNF-e membranes with covalently immobilized ciprofloxacin remain contact active for several days. These 100% CNF active nanostructured membranes can be used as new wound dressing for topical application.

In this study, the grafting of 1-methyl-3-phenylpropylamine (1-M-3-PP) on cellulose nanocrystals (CNCs) via a two-step reaction route was investigated and compared with physico-chemical surface adsorption. The first step involved subjecting CNCs to a 2,2,6,6-Tetramethyl-1-piperidinyloxy (TEMPO)-mediated oxidation. The carboxylic groups present on recovered oxidized TEMPO-CNC were quantified by several characterization methods (conductometric titration, elemental analysis, and X-ray photoelectron spectroscopy), and a degree of oxidation close to 0.2 was found. The second step was an amidation reaction carried out in an aqueous medium under mild conditions and in the presence of N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide (EDC)/N-hydroxysuccinimide (NHS) as catalyst. The recovered modified CNCs after amidation reaction with 1-M-3-PP (CNC-1-M-3-PP) were extensively washed and then characterized. The amount of grafted molecules was determined by several techniques like X-ray photoelectron spectroscopy (XPS), and the calculated degree of substitution was found to be close to 0.05 with respect to the bulk CNC. This low amount is sufficient to enhance the modified CNC dispersion and their colloidal stabilization in organic solvents, allowing the preparation of nanocomposites. Furthermore, such CNC-1-M-3-PP units with aromatic molecules attached to it can find applications in barrier materials in which the sorption of aromatic molecules can be very useful.

The present study was conducted to determine the abilities of the living Lactobacillus plantarum MON03 cells to degrade Zearalenone (ZEN) in liquid medium, and to elucidate the preventive effect in ZEN-contaminated balb/c mice showing kidney damage. The DNA fragmentation, Bcl-2 and Bax gene expression, caspase-3 activity, mRNA level of inflammation-regulating cytokines and histology of kidney tissues were examined. Female Balb/c mice were divided into four groups (10/group) and treated daily for 2 wk by oral gavage with lactic acid bacteria (L. plantarum MON03) 2 × 109 CFU/L, ~2 mg/kg only, ZEN (40 mg/kg BW) only, ZEN (40 mg/kg BW) + lactic acid bacteria (L. plantarum MON03, 2 × 109 CFU/L, ~2 mg/kg). Control group received vehicle. At the end of experiment, the kidney was collected for the determination of DNA fragmentation, Bcl-2 and Bax gene expression,caspase-3 activity, Malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) content, as well as for any alterations in expression of total antioxidant activity (TAC) and mRNA levels of inflammation-regulating cytokines (e.g., IL-10, IL-6, TNF-alpha). The results indicated that, kidney cells exposure to ZEN led to increased caspase-3 activity, MDA, and IL-10, IL-6, TNF-alpha and Bax mRNA levels, but decreased TAC content and down-regulated expression of GSH-Px and CAT and Bcl-2 mRNA. Co-treatment with ZEN plus LP suppressed the levels of DNA fragmentation; normalized kidney MDA and increased CAT levels, up-regulated expression of GSH-Px and CAT, and normalized mRNA levels of the analyzed cytokines. It's concluded that ZEN might have toxic effects in kidney. Further, it can be seen that use of LP induced protective effects against the oxidative stress and kidney toxicity of ZEN in part through adhesion (and so likely diminished bioavailability).

International audience; Novel p-type SrSn 1-x Al x O 3 (x=0, 0.2, 0.5) perovskites are presented as potential candidates for electro-optical applications. A combined experimental and theoretical study reveals that chemical substitutions can be used as a lever to stabilize oxygen holes in the valence band. Transparent conductive oxides (TCO) are an original class of materials combining two contrasting properties in one single compound that is, electrical conductivity and optical transparency in visible spectrum. TCOs are widely used in electro-optical devices such as flat-panels, organic light emitting diodes, photovoltaic devices, and plasma displays. 1-6 However, standard commercial TCOs are limited to post-transition metal oxides, e.g. ZnO, In 2 O 3 and SnO and derivatives. 7 These oxides are characterized by a band gap larger than 3eV between the O(2p) valence band maximum (VBM) and the metal (s,p) conduction band minimum (CBM). They display excellent n-type electronic conductivity when the donor, i.e. metal, is doped. In contrast, the development of high performant p-type TCOs is more challenging, 8-11 due to the strongly localized states of the acceptor, i.e. oxygen, which are at the origin of large hole effective mass (poor electronic conductivity). As a consequence, the probability is high that the newly created shallow acceptors are counterbalanced by the formation of native defects such as anion vacancies or cation interstice. 12 Up to now, n-type tin-doped indium oxide (ITO) shows the best performance. 1,13 Nevertheless and despite the remarkable properties of ITO, the relative high cost of In and its increasing scarcity appeals for alternative elements or materials. 14 ABO 3 perovskites are of great interest thanks to the use of mixed A and B cations capable of generating versatile structures and properties with high chemical stability. SrSnO 3 (SSO) is one of the most promising candidate due to its high visible light transmittance, high thermal stability and reasonable cost. 15 Pure SSO is a charge transfer insulator crystallizing in the orthorhombic GdFeO 3-type structure with lattice parameters a = 5.7113 Å, b = 8.0647 Å and c = 5.7042 Å. In this tri-dimensional structure, SnO 6 octahedra are corner-shared and Sr lies in the available vacant interstices. 16,17 To meet the industrial specifications of efficient TCOs, SSO must display high carrier concentration and mobility 18-21 which requires its doping. Attempts to develop n-type SSO candidates that could rival the electro-optical properties of ITO were intensively described and interesting performance were reported. 22-26 In contrast, p-type doping is still lacking for this class of materials. 27-29 Recently, Hautier et al. showed that the large difference in mobility between n-type and p-type materials is not inevitable and could be overcome by the investigation of alternative chemistries. Based on this statement and considering the high industrial stakes associated with the discovery of new p-type TCOs, we used chemical substitution to check the ability of SSO to behave as a performant p-type TCO. This concept was introduced for the first time by Hosono and coworkers 2 and is known as the "chemical modulation of the valence band" (CMVB). Based on the hypothesis that partial substitution of Sn(IV) for the smaller trivalent cation Al(III) can enhance electron delocalization (through a significant volume contraction of the perovskite structure) while concomitantly generate stable holes in the valence band, various Sn/Al-substituted SSO phases were synthesized. Using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) equipped with Energy Dispersive X-ray Spectroscopy (EDX), we here demonstrate the solubility of the Al element in the SSO perovskite structure for SrSn 1-x Al x O 3 (SSAO) compositions x = 0 to 0.5. UV-Vis-NIR spectroscopy is then used to show that the absorption profile of SSO is not altered by the chemical Sn/Al substitution while the low-energy absorption band (intra-band transitions) is enhanced. A thermodynamic study based on first-principles DFT (Density Functional Theory) calculations is then performed to determine the type of charge carriers in SSO and SSAOs (p-type) and combined with chemical bond analyses to rationalize the impact of Sn/Al substitution on the p-type performance of SSAOs. SrSn 1-x Al x O 3 (x= 0, 0.2, 0.5) perovskites were successfully obtained through solid state reaction. Details of the synthesis steps are given in ESI part. The impact of the Sn(IV)/Al(III) substitution ratio on the macroscopic properties of SrSn 1-x Al x O 3 was investigated through complementary XRD and SEM-EDX. The structural and morphological analyses of the synthesized samples are presented in Fig.1 and S1. From the XRD patterns of SSO and SrSn 1-x Al x O 3 (SSAO) the orthorhombic Pnma structure (JCPDS 10-6354) is confirmed. A slight shift towards higher angles is observed in agreement with the smaller Shannon ionic radius of Al 3+ (0.54 Å) compared to Sn 4+ (0.69 Å).

The study deals with the synthesis of thermally reversible hydrogels from modified cellulose nanofibers via the Diels-Alder “click” reaction in an aqueous medium. “Never-dried” cellulose fibres derived from hardwood were submitted to shearing and surface TEMPO-oxidation before being modified with furfurylamine. The ensuing pendant furan moieties were reacted with a water-soluble bismaleimide via Diels-Alder coupling at 65 °C to produce a hydrogel, whose deconstruction was induced by the corresponding retro-Diels-Alder reaction carried out at 95 °C. Differential scanning calorimetry and rheological measurement were used to characterize the hydrogels. These aqueous cellulosic materials should provide original applications in such areas as strong paper-based artefacts and biocompatible gels.

Fumonisin B1 (FB1) is a carcinogenic (Class 2B) mycotoxin produced by Fusarium fungi and is responsible for several types of mycotoxicoses in animals and humans. Lactobacillus paracasei (LP), as a probiotic, is known to impart a wide range of advantageous effects on host health. The objective of the current study was to evaluate if LP (type BEJ01) isolated from Tunisian artisanal butter, could potentially help protect a host against intestinal alterations caused by exposure to FB1. Here, adult male Balb/c mice were randomly assigned to four groups, i.e., control (vehicle only), treated with FB1 (100 µg/kg BW), LP (2 × 109 CFU/ml [≈ 2 mg/kg BW]) and FB1 (100 µg/kg BW) + LP (2 × 109 CFU/ml) and treated per os daily for 10 days. At 24 hr after the final treatment, mice were euthanized and their jejunum harvested for examination of intestinal alterations induced by the FB1. The data showed that a variety of negative effects in jejunal tissue were induced by the FB1, including DNA fragmentation, oxidative stress, apoptotic cell death, and histopathological alterations. The results also showed that co-treatment of LP with FB1 was able to mitigate the harmful FB1 effects. LP alone imparted no damage to jejunal tissues. These results show that apart from potential use as a bio-preservative for extending the shelf-life of food and feeds, LP may also provide a benefit of helping prevent untoward effects from a potent mycotoxin like FB1.

openaire: EC/H2020/788489/EU//BioELCell Funding Information: The authors would like to thank S-Fly and Die Wurm Farm for providing the raw materials needed for this study and Tuyen Nguyen for the fluidization of the different ChNFs. LGP2 is part of the LabEx Tec 21 (Investissements d’Avenir - grant agreement no. ANR-11-LABX-0030) and of the PolyNat Carnot Institute (Investissements d’Avenir - grant agreement no. ANR-16-CARN-0025-01). This work was supported by Grenoble INP, “Bourse Présidence”, and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement no. 788489). O.J.R. also acknowledges the Canada Excellence Research Chair initiative and the Canada Foundation for Innovation (CFI). Support from the Austrian Biorefinery Center Tulln (ABCT) is gratefully acknowledged. Publisher Copyright: © 2021 American Chemical Society. Nowadays, environmental concerns make us rethink the way that we live and eat. In this regard, alternative protein sources are emerging; among them, insects are some of the most promising alternatives. Insect farming is still an infant industry, and to improve its profitability and environmental footprint, valorization of the byproducts will be a key step. Chitin as the main polysaccharide in the exoskeleton of insects has a great potential in this regard and can be processed into high value-added materials. In this study, we extracted and fibrillated chitin fibers from fly larvae (Hermetia illucens) and compared them with commercial chitin from shrimp shells. A mix of chitin and cellulose fibers was also extracted from mealworm farming waste. The purified chitinous fibers from different sources had similar chemical structures as shown by Fourier transform infrared and nuclear magnetic resonance spectroscopies. After mechanical fibrillation, the nanostructures of the different nanofibers were similar with heights between 9 and 11 nm. Chitin nanofibers (ChNFs) from fly larvae presented less nonfibrillated fiber bundles than the shrimp-derived analogue, pointing toward a lower recalcitrance of the fly larvae. ChNF suspensions underwent different film-forming protocols leading to films with tensile strengths of 83 ± 7 and 71 ± 4 MPa for ChNFs from shrimp and fly, respectively. While the effect of the chitin source on the mechanical properties of the films was demonstrated to be negligible, the presence of cellulose nanofibers closely mixed with ChNFs in the case of mealworm led to films twice as tough. Our results show for the first time the feasibility of producing ChNFs from insect industry byproducts with high potential for valorization and integral use of biomass.

This study concerns the preparation of sprayed binary molybdenum oxide, MoO3, thin films and ternary and quaternary derivatives by alloying. The characterization of their physical properties was carried out by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, spectrophotometry and impedancemetry. It appears from the electrical study that the great value of resistance R corresponds to the NiMoO4 thin films. The equivalent ac circuit of these films is composed by a parallel resistor R and capacitor C connected together. This work also focused on the photocatalysis process applied to the studied samples. Under solar irradiation, the photocatalytic application was tested in terms of the degradation reaction of wastewater containing methylene blue. Under similar experimental conditions, the NiMoO4 thin film shows a higher rate of degradation than the other thin layers.

In this work, date palm waste (DPW) stemming from the annual pruning of date palm was used as a reinforcing filler in polypropylene matrix at 20–60 wt.%. Only a grinding process of the DPW has been performed to ensure no residue generation and full utilization. The present work investigates how the DPW use affects mechanical properties and water absorption of the ensuing composite. The effect of the addition of maleated polypropylene (MAPP) as a coupling agent on the composite properties was also studied. It was shown that the reinforcing potential of DPW was strongly dependent on aspect ratio and interface quality. The MAPP addition resulted in a composite with higher strength and stiffness than the neat PP, meaning that DPW behaves as reinforcement. The difference in the reinforcing effect was explained by the change in the quality of the interface between date palm waste and the polypropylene polymeric chain.

Fusarium graminearum invasion and Zearalenone (ZEN)-mycotoxin contamination are considered the most global threat to food and feed. This study investigates the effect Lactobacillus plantarum MON03 viable cells (LPVC) and LP free cells supernatant (LPFCS) against Fusarium graminearum growth and ZEN production in vitro and evaluates if treatment with LP viable cells can counteract the negative effect of ZEN on inflammation and oxidative stress in mesenteric lymph nodes and serum biochemical parameters in mice. For the in vitro study, 7 days of LPVC, LPFCS and F. graminearum co-incubation at different concentrations was done in order to determine the antifungal activity and ZEN- production inhibition. Regarding the in vivo study, Balb/c mice were treated as following: Control, ZEN group, LP group and ZEN + LP group for 30 days. In vitro, LPVC showed an excellent antifungal activity after 7 days of co-incubation (103 CFU/ml). LPVC was succeeded also to inhibit ZEN production by the fungi. In vivo, ZEN has shown an important oxidative damage. As a result of the exposure to ZEN, an increase cytokines, as effectors of an inflammatory response, were observed in the mesenteric lymph nodes (MLN) of intoxicated mice. In parallel, a serum biochemical change was also observed. LPVC induced a reduction of ZEN-induced oxidative stress and counteracts also the biochemical parameters damage and the inflammatory markers increased by ZEN. LPVC can be valorized as an anti-cating agent in the vitro and in the gastro-intestinal tract to decrease ZEN-toxic effects.

Cellulose nanofibrils (CNF) are renewable bio-based materials with high specific area, which makes them ideal candidates for multiple emerging applications including for instance on-demand drug release. However, in-depth chemical and structural characterization of the CNF surface chemistry is still an open challenge, especially for low weight percentage of functionalization. This currently prevents the development of efficient, cost-effective and reproducible green synthetic routes and thus the widespread development of targeted and responsive drug-delivery CNF carriers. We show in this work how we use dynamic nuclear polarization (DNP) to overcome the sensitivity limitation of conventional solid-state NMR and gain insight into the surface chemistry of drug-functionalized TEMPO-oxidized cellulose nanofibrils. The DNP enhanced-NMR data can report unambiguously on the presence of trace amounts of TEMPO moieties and depolymerized cellulosic units in the starting material, as well as coupling agents on the CNFs surface (used in the heterogeneous reaction). This enables a precise estimation of the drug loading while differentiating adsorption from covalent bonding (∼1 wt% in our case) as opposed to other analytical techniques such as elemental analysis and conductometric titration that can neither detect the presence of coupling agents, nor differentiate unambiguously between adsorption and grafting. The approach, which does not rely on the use of 13C/15N enriched compounds, will be key to further develop efficient surface chemistry routes and has direct implication for the development of drug delivery applications both in terms of safety and dosage., DNP-enhanced solid-state NMR unravels the surface chemistry of functionalized nanocellulose.

Quality and food safety represent a major stake and growing societal challenge in the world. Bacterial contamination of food and water resources is an element that pushes scientists to develop new means for the rapid and efficient detection and identification of these pathogens. Conventional detection tools are often bulky, laborious, expensive to buy, and, above all, require an analysis time of a few hours to several days. The interest in developing new, simple, rapid, and nonlaborious bacteriological diagnostic methods is therefore increasingly important for scientists, industry, and regulatory bodies. In this study, antibiotic-functionalized metallic nanoparticles were used to isolate and identify the foodborne bacterial strains Bacillus cereus and Shigella flexneri. With this aim, a new diagnostic tool for the rapid detection of foodborne pathogenic bacteria, gold nanoparticle-based centri-chronoamperometry, has been developed. Vancomycin was first stabilized at the surface of gold nanoparticles and then incubated with the bacteria B. cereus or S. flexneri to form the AuNP@vancomycin/bacteria complex. This complex was separated by centrifugation, then treated with hydrochloric acid and placed at the surface of a carbon microelectrode. The gold nanoparticles of the formed complex catalyzed the hydrogen reduction reaction, and the generated current was used as an analytical signal. Our results show the possibility of the simple and rapid detection of the S. flexneri and B. cereus strains at very low numbers of 3 cells/mL and 12 cells/mL, respectively. On the other hand, vancomycin-capped magnetic beads were easily synthesized and then used to separate the bacteria from the culture medium. The results show that vancomycin at the surface of these metallic nanoparticles is able to interact with the bacteria membrane and then used to separate the bacteria and to purify an inoculated medium.

Date palm waste is an abundant agricultural residue in Tunisia and can be used for plastic reinforcement. Moreover, its use in plastic composites can help to reduce dependence on fossil resources for material production. In this work, the valorization of date palm residues was studied by employing high-yield processes following mechanical, chemical, and enzymatical treatments. Fibers obtained by soft chemical treatment with sodium hydroxide and enzymatic treatment with xylanases and pectinases were evaluated for their use in the reinforcement of plastic materials. The flexural strength property, truly relevant for structural, construction, automotive, or other market sectors, was adopted to assess the reinforcing potential of the fibers. Polypropylene was effectively reinforced with date palm fibers (60 wt.%), exhibiting a flexural strength increases of 80% (73.1 MPa), 93% (78.5 MPa), and 106% (83.9 MPa) for mechanical, chemical, and enzymatic fibers, respectively. The different treatments had an impact on the chemical composition of the fibers, and by extension on the final properties of the composites. The holocellulose content could provide good interfacial adhesion using a coupling agent, whereas the lignin content improved the dispersion of the phases. Two interesting outcomes were that the flexural performance of enzymatic fibers was like that of wood composites, whereas the specific flexural strength was comparable to that of glass fiber composites. Overall, the present work has shown the potential behind date palm waste in the composite sector when a specific property or application is desired. Novel treatments have been used for greater fiber compatibility, increasing the sustainability of the process, and improving the applicability of the palm residue.

Phosphorylated cellulose nanofibrils (CNFs) were produced using a twin-screw extruder (TSE). The energy efficiency was compared with that of an ultra-fine grinder (UFG). CNFs at different solid contents were produced (10 wt% for the TSE and 2 wt% for the UFG), and their quality was compared using several characterization tests, such as optical microscopy, atomic force microscopy or MorFi fiber analyser. CNF nanopapers with high a Young’s modulus (14 GPa) and high transparency were successfully manufactured using CNFs produced by the TSE. The efficiency of the TSE was improved by using phosphorylated pulp instead of mechano-enzymatically treated pulp. The results show that phosphorylated CNFs can be easily produced at the industrial scale via twin-screw extrusion and present new functionalities such as fire-retardant properties, which are useful in many applications.

Aphis gossypii (Glover) is one of the major pests of melon crops as well as an efficient vector of non-persistent virus such as Cucumber Mosaic Virus and Zucchini Yellow Mosaic Virus among others. Host-plant resistance is one of the best strategies that can be used to control this pest. In this study 14 Tunisian melon accessions were screened to identify new sources of resistance/tolerance to Aphis gossypii using phenotypic and molecular approaches. Antixenosis, antibiosis and tolerance tests were carried out to phenotype those accessions which were also analyzed by molecular markers linked to the Vat gene which confers resistance to both A. gossypii colonization and virus transmission. Results evidenced that only the accession TUN-7 showed antixenosis, antibiosis and tolerance (no leaf curling), at a similar level to that of the resistant control PI414723. Although plants of the accession TUN-13 did not show leaf curling either, the presence of the Vat gene was only detected in TUN-7; its fruit characteristics, of Ananas type, makes this accession as a valuable source of resistance to this aphid that can be used in breeding programs to develop new aphid resistant melon cultivars.

In this study, an innovative and green process to produce cellulose nanofibers (CNFs) is proposed. CNFs are usually produced via mechanical, enzymatic, and/or chemical treatment such as (2,2,6,6-te...

Ring growth in cement rotary kilns is a complex and a dynamic phenomenon, where the agents responsible for their formation cannot be easily controlled. This is reflected by the mineralogical heterogeneity of the deposit material. In this context, eight samples collected from two rings, formed in the same kiln, but at different periods (during 22 and 3 days), were subjected to qualitative and quantitative mineralogical study. The consolidation of these rings was the result of the combined deposition of the carbonates and the sulphates phases. The analyzes were focused mainly on spurrite Ca5(SiO4)2CO3, calcite CaCO3, sulfospurrite Ca5(SiO4)2(SO4), Ca –Langbeinite K2Ca2(SO4)3 and chlorellestadite Ca10(SiO4)3(SO4)3Cl2. Their identifications and quantifications joined to the variation of sulfur amount and the calcination degree of the hot meal, permitted to better modulate the mechanism of ring formation in the kiln inlet.

International audience; New designer drugs, as synthetic cannabinoids (SCs), continuously appear on the market and are booming due to their cannabis-like effect. New generation of smokable SCs, structurally dissimilar from Δ9-tetrahydrocannabinol (THC), have isomers with distinguishable pharmacokinetic parameters and therefore different in vivo effects. The isoforms are misidentified using conventional techniques such as gas or liquid chromatography coupled to mass spectrometry - or tandem mass - spectrometry. The aim of this study was to differentiate three positional isomers (JWH-007, JWH-019 and JWH-122) in single human hair samples, which store numerous substances revealing a way of life and consumption style. Matrix-assisted laser desorption/ionization (MALDI) combined with imaging is an innovative and powerful tool used since few years, especially in forensic research. Herein, we propose an innovative method to monitor the drugs of abuse consumption through direct mapping of the compounds with a high spatial distribution in human hair samples, by state-of-art imaging MALDI-MSn. Three positional SC isomers (JWH-007, JWH-019 and JWH-122) were analysed using high and low fragmentation energy and the resulting MS/MS and even MS3 spectra differentiated the SCs. The MALDI-MS/MS and MS3 imaging was performed on hair soaked in a mixture of the three SCs as well as on hair from self-reported SC user, proving the potential of the technique for a forensic use. Keeping in mind that spatial distribution of organics from whole hair remains a challenge, the described methodology is a very promising analytical tool to probe the consumption of complex drugs and obtain correlation with its origin.

In arid and semi-arid areas, the water quantity and quality is a great problem. Salinzation is the major threat in the region of Menzel Habib (north-western Gabès, southeastern Tunisia). The region is a large basin which is essentially represented by sandy-clay formations and bordered by cretaceous reliefs. Geochemical and statistical approaches are reported in the Menzel Habib Aquifer system to examine groundwater salinization processes and factors controlling its mineralization. Geochemical studies were developed in 25 groundwater samples from the shallow aquifer to identify the origin of groundwater salinization. Groundwater geochemistry shows a high correlation between salinity and Na, Cl, Ca, Mg and SO4. These elements are mainly associated to the evaporitic Triassic by dissolution of halite, anhydrite and gypsum which occur on the area and is related to the tectonic context of the region. Additionally, bivariate diagram beween Na and Cl, and Ca and SO4 have also provided a comprehensive understanding of other salinization processes that are involving in Menzel Habib shallow aquifer such as cation exchange and reverse cation exchange., This work is co-funded by the European Union through the European Regional Development Fund, based on COMPETE2020, project ICT (UID/ GEO/04683/2013) with reference POCI- 01-0145-FEDER-007690 by FCT.

UV-vis and impedance measurements were performed to determine the stable formation of the Hydroxychloroquine-Zinc (HCQ-Zn) complex within the oleic acid (oil) phase of the oil-water system. Decreased UV absorbance with increased Zn concentration was associated with the gradual formation of the complexes within the oil phase, agreeing with existing reports and our time-dependent-density-functional calculations. The reproducibility of our data over a long period indicates the stability of the complex within the oil phase. The impedance measurement showed that the dielectric loss of the oil phase due to the polarization of the complex is less than that due to the polarization of HCQ. A basic impedance measurement revealed that the aqueous-to-oil transfer of Zn is not possible without the HCQ, a result pertinent to the recent report that HCQ is Zn ionophore. Our work is thus important to the fundamental physical chemistry and the current COVID-19 issue where the Zn infusion across the living cell phospholipid membrane (mimicked as an oil-water interface) reduces viral replication.

International audience; In this study, a new approach to optimize the cellulose nanocrystals (CNCs) extraction using acidic natural deep eutectic solvents (NADES) was introduced using, for the first time, design of experiment method. Choline chloride:oxalic acid dihydrate with a molar ratio of 1:1 was used to extract CNCs. Then, three most important parameters were varied to design the experiment: (i) cotton fibre concentrations, (ii) temperature and (iii) treatment time. Two outcomes were studied: the CNC yield and the crystallinity. The mathematical model for crystallinity perfectly described the experiments, while the model for CNC yield provided only a tendency. For a reaction time of 6 h at 95°C with a fibre concentration of 2%, the expected optimum CNC yield was approximately 35.5 ± 2.7% with a crystallinity index of 80 ± 1%. The obtained experimental results confirmed the models with 43.6 ± 1.9% and 81 ± 1% for the CNC yield and the crystallinity index, respectively. This study shows that it is possible to predict the CNC yield CNC and their crystallinity thanks to predictive mathematical models, which gives a great advantage to consider in the near future a scale up of the extraction of cellulose nanocrystals using this original family of green solvents.

Ocean life relies on the loads of dissolved inorganic nutrients (nitrate, phosphate and silicate) and other micro-nutrients into the euphotic layer. They fuel phytoplankton growth that maintains the equilibrium of the food web. Ocean circulation and physical processes continually drive the large -scale distribution of chemicals toward a homogeneous distribution (Williams and Follows, 2003). The biological and biochemical processes counteract this tendency. Therefore, describing nutrient dynamics is important to understand the overall ecosystem functioning.At global scale, most of the biogeochemical descriptions are based on model simulations and satellite data, since nutrient in situ observations are generally infrequent and not homogeneously distributed in space and time. Climatological mapping is often used to understand the biogeochemical state of the ocean representing monthly, seasonally or annual averaged fields.Within this context, the western Mediterranean Sea climatology (BGC-WMED) presented here is a product derived from in situ observations, derived from various data sources: in total, 2253 in-situ inorganic nutrient profiles over the period 1981-2017 have been used (Medar/MEDATLAS, Fichaut et al., 2003; the CNR-WMED biogeochemical dataset, Belgacem et al., 2020; SeaDataNet data product, https://www.seadatanet.org; Mediterranean Ocean Observing System for the Environment, MOOSE, http://www.moose-network.fr/).Annual mean gridded nutrient fields for the period 1981-2017, and sub-periods 1981-2004 and 2005-2017, on a horizontal 1/4° × 1/4° grid have been produced. The biogeochemical climatology is built on 19 depth levels and for the dissolved inorganic nutrients nitrate, phosphate and orthosilicate. To generate smooth and homogeneous interpolated fields, an advanced N-dimensional version of DIVA, DIVAnd v2.5.1 (Barth et al., 2014), which is based on the variational inverse method (VIM) (Brasseur et al., 1996), has been used.A sensitivity analysis was carried out to assess the comparability of the data product with the observational data. The BGC-WMED has then been compared to other available data products, i.e. the medBFM biogeochemical reanalysis and the biogeochemical component of WOA18.Keywords: Mediterranean Sea, climatology, inorganic nutrient, in situ observations.

openaire: EC/H2020/788489/EU//BioELCell Cellulose (CNF) and chitin (ChNF) nanofibers are known to form materials that are both tough and strong. In this study, we hypothesize that the inertness of networks produced from CNF and ChNF makes them ideal templates for heterogeneous reactions and in situ formation of nanoarchitectures. We expand nanoparticle templating on polysaccharide colloids by introducing a new and facile process that leads to the growth of organic nanoparticles on CNF and ChNF in aqueous media. The process, based on solvent shifting supported on solid interfaces, is demonstrated by direct observation of lignin nanoparticles that are further used for their photocatalytic activity. Importantly, the dynamics of nanoparticle nucleation and growth is correlated with the surface chemistry of the templating nanopolysaccharides. Electrostatic repulsion between the deprotonated lignin molecules and the slightly negative CNF support led to limited adsorption and was effective in producing free (nonbound) lignin nanoparticles (28 ± 7 nm) via precipitation. In contrast, the stronger interfacial interactions between the positively charged ChNF and lignin molecules facilitated instantaneous and extensive lignin adsorption, followed by nucleation and growth into relatively larger nanoparticles (46 ± 17 nm). The latter were homogeneously distributed and strongly coupled to the ChNF support. Overall, we introduce lignin nanoparticle nucleation and growth on renewable nanopolysaccharides, offering an effective route toward in situ synthesis of highly functional fibrils and related cohesive films that offer a great potential in packaging and other applications.

The chapter is on development and application of matrix assisted laser desorption ionisation time of flight mass spectrometry (MALDI-TOF) to identification and and classification of bacteria.

In this study a tri-generation system, using solar energy as the main energy source was studied. The system contains a photovoltaic generator, a solar water heater system, an absorption chiller, an electrolyzer and a fuel cell to produce electrical energy, heat and cooling for air conditioning. The system was modelled and simulated in Algiers. We found that it can provide energy autonomously to a single-family home without the need for any external supplement.

Nowadays, drug encapsulation and drug release from cellulose nanofibrils systems are intense research topics, and commercial grades of cellulose nanomaterials are currently available. In this work we present an ester-containing prodrug of metronidazole that is covalently bound to cellulose nanofibrils in aqueous suspension through a two-step immobilization procedure involving green chemistr y principles. The presence of the drug is confirmed by several characterization tools and methods such as Raman spectroscopy, elemental analysis, Dy-namic Nuclear Polarization enhanced NM R . This technique allow s enhancing the sensitivity of NM R by several orders of magnitude. It has been used to study cellulose nanofibrils substrates and it appears as the ultimate tool to confirm the covalent nature of the binding through thiol-yne click chemistry. Moreover, the ester function of the immobilized prodrug can be cleaved by specific enzyme activity thus allowing controlled drug release.