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The activation of the human immunodeficiency virus, type 1 (HIV-1) by the DNA alkylating agents ethyl methanesulfonate, methyl methanesulfonate, and mitomycin C was observed in human B lymphocytes transiently transfected with plasmids in which the HIV-1 long terminal repeat (LTR) directed the expression of the bacterial chloramphenicol acetyltransferase gene. Deletion of the two NF-kappa B-binding sites of LTR abolished the HIV-1 activation induced by the three mutagens, while deletion of the three Sp1-binding sites slightly reduced it. Electrophoretic mobility shift assays revealed an increased binding to the kappa B sites of HIV-1 LTR in the nuclear extracts of human B lymphocytes upon mutagen treatment, while binding to Sp1 sites was unaffected. The TAR region was also involved in the mutagen-mediated activation of HIV-1 LTR inasmuch as a small deletion in the TAR sequence (nucleotides +34 to +37) greatly decreased the induction of HIV-1 expression. Moreover, an enhanced binding activity to the TAR DNA sequence (nucleotides +24 to +47) was observed in nuclear extracts of mutagen-treated lymphocytes. Thus, both the enhancer and the 5'-untranslated region of HIV-1 functionally cooperate in the mutagen-mediated induction of HIV-1 expression.

The increasing depletion of fossil feeds and the environmental concerns linked to the use of traditional energy sources have stimulated both academic and industrial worlds in exploiting new sustainable and renewable suppliers of raw materials [1]. In this framework, lignocellulosic biomass can play an important role, acting as the starting material of a biorefinery leading to biofuels, chemicals, and other value-added products, commonly obtained from petroleum. Recently, numerous protocols for processing lignocellulosic biomass of selected plants have been reported. However, developing an environment-friendly method is still a big goal. This challenge becomes more interesting if lignocellulosic biomass coming from wood wastes could be efficiently treated. Deep eutectic solvents (DESs) are new sustainable and cheap reaction media, combining the features of ionic liquids and organic solvents. They are made by association of hydrogen-bond donors and hydrogen-bond acceptors, and they can promote the hydrolysis of lignocellulosic bonds [2]. Herein, we report on the microwave-assisted treatment of waste wood flours with DESs formed by choline chloride and oxalic acid to get a cellulosic residue separated from lignin degradation products, identified by NMR spectroscopy. The insoluble deposit was characterized by SEM, TGA, DSC, FTIR-ATR and 13C CP/MAS NMR techniques and could be available for further uses such as nanocellulose production. [1] Haldar D., Purkait M.K. Chemosphere 2021, 128523. [2] Liu S., Zhang Q., Gou S., Zhang L., Wang Z. Carbohydr. Polym. 2021, 251, 117018

In recent years, considerable progress has been made in exploring new applications of fuel additives to reduce emissions. Reduction of total nitrogen oxide (NOx) emissions can be achieved by decreasing the flame temperature by using fuel emulsified with water and/or using ammonia-based nano additives such as urea. The use of water as part of the hydrocarbon fuel is also one of the prospective directions in the development of new types of fuel systems. For the preparation of emulsified fuel, it is desirable to achieve greater stability of the emulsified fuel with minimum expenditure of chemicals and energy, so that the emulsified fuel can be used for a longer period. The paper analyzed the influence of nano-dispersed urea particles, water, and surfactant (Span 80/Tween 80) on the combustion stability and emission characteristics of aviation fuel. The experimental campaign was conducted on a test stand (a 300kW liquid vortex combustor of 300 kW) consisting of a cylindrical combustion chamber with four optical windows and equipped with high-precision pressure sensors, thermocouples, and an exhaust gas analyzer for acquiring emissions. The experimental campaign was conducted at a constant fuel/air ratio (Φ). One of the main focus is related to the stability of the emulsion. Chemiluminescence imaging was performed to characterize the effects of the additive on flame emissions. In addition, a statistical and spectral analysis was performed using the pressure sensor for instability analysis. Exhaust gas analysis was performed both with the additive described above and without additive for a constant Φ condition. The analysis was performed for NOx, carbon monoxide (CO) and carbon dioxide (CO2) and oxygen (O2).

Nature offers interesting structures and chemicals for photochemistry and photocatalysis. Therefore, highly performing photocatalysts have been derived with improved morphology, photoadsorption, energy transfer, and photostability. Different green synthesis methods have been developed employing phytochemicals, biotemplates, and bioreactors. Smart natural hierarchical structures and enzyme-like materials have been faithfully reproduced providing unique physico-chemical proprieties and constructing artificial photosynthesis. Hybridization with natural pigments and polymers has been investigated, obtaining a new class of heterogenous nano-photocatalysts with improved dispersibility and efficacy. A biology-inspired approach has expanded the spectrum of photocatalysis applications carrying out increasingly biocompatible and effective systems for bioremediation, active food packaging, and nanomedicine.

Olive quick decline syndrome (OQDS) is a multifactorial disease affecting olive plants. The onset of this economically devastating disease has been associated with a Gram-negative plant pathogen called Xylella fastidiosa (Xf). Liquid chromatography separation coupled to high-resolution mass spectrometry detection is one the most widely applied technologies in metabolomics, as it provides a blend of rapid, sensitive, and selective qualitative and quantitative analyses with the ability to identify metabolites. The purpose of this work is the development of a global metabolomics mass spectrometry assay able to identify OQDS molecular markers that could discriminate between healthy (HP) and infected (OP) olive tree leaves. Results obtained via multivariate analysis through an HPLC-ESI HRMS platform (LTQ-Orbitrap from Thermo Scientific) show a clear separation between HP and OP samples. Among the differentially expressed metabolites, 18 different organic compounds highly expressed in the OP group were annotated; results obtained by this metabolomic approach could be used as a fast and reliable method for the biochemical characterization of OQDS and to develop targeted MS approaches for OQDS detection by foliage analysis.

Europium-doped hydroxyapatite Ca10(PO4)6(OH)2 (3% mol) powders were synthesized by an optimized chemical precipitation method at 25 &deg, C, followed by drying at 120 &deg, C and calcination at 450 &deg, C and 900 &deg, C. The obtained nanosized crystallite samples were investigated by means of a combination of inductively coupled plasma (ICP) spectroscopy, powder X-ray diffraction (PXRD), Fourier Transform Infrared (FTIR), Raman and photoluminescence (PL) spectroscopies. The Rietveld refinement in the hexagonal P63/m space group showed europium ordered at the Ca2 site at high temperature (900 &deg, C), and at the Ca1 site for lower temperatures (120 &deg, C and 450 &deg, C). FTIR and Raman spectra showed slight band shifts and minor modifications of the (PO4) bands with increasing annealing temperature. PL spectra and decay curves revealed significant luminescence emission for the phase obtained at 900 &deg, C and highlighted the migration of Eu from the Ca1 to Ca2 site as a result of increasing calcinating temperature.

Stone is one of the most durable construction materials used in historic buildings all over the world. However, over time, the stone can be subject to various degradation processes leading to physical and chemical modifications. Although these effects may be limited to the surface and negligible to the structural stability of the affected buildings, they can represent a major problem in decorative elements of artistic value, where any detail should be preserved [1]. The challenge for conservators and material scientists involved in stone conservation has always been to find a way to stop or delay the effects of these degradation processes. The basic principle of the patrimony is that the cultural heritage is an incalculable and integral legacy to our future: observing and knowing the past, will help next generations to better challenge the future. Thus, conservation of stone heritage is always a delicate and complex task, due to the multiple variables that have to be taken into account to identify the problems, and to define the necessary conservation actions and to select materials and best procedures to be used. The variety of factors to be analyzed includes the intrinsic stone properties (from geological features up to mechanical behavior), the state of conservation, the degradation mechanisms and the environmental factors. One of the most promising technology employed for lowering the previously described degradation processes, is that of nanomaterials, nowadays largely applied in the maintenance of the world cultural heritage, with the aim of improving the consolidation and protection treatments of damaged stone materials they are made of [2]. Such nanomaterials display important advantages that could solve many problems found in the traditional interventions, that often showed the serious bias of the lack the vital compatibility with the original substrate and a durable performance: application of nanotechnology in the cultural heritage conservation is characterized by the possibility to design consolidant products strongly compatible with the original stone substrate. Moreover, when particles have dimensions of about 100 nanometers, the material properties change significantly from those at larger scales. The nanoparticles must show: stability and sustained photoactivity; biological and chemical inactivity nontoxicity, as well as antimicrobial properties for lowering ecotoxicological impact on animals and plants [3]; low cost suitability towards visible or near UV light; high conversion efficiency and high quantum yield. In addition, these treatments can also have water repellent properties which favor this self-cleaning action and prevent the generation of damage caused by water. The most commonly used inorganic consolidant agents are the products based on Ca(OH)2 calcium hydroxide nanoparticles [4], due to their compatibility with a large part of the built and sculptural heritage. As well as other hydroxides (Mg(OH)2, Sr(OH)2), metal oxides (TiO2, ZnO), and metal nanoparticles (Au, Ag, Pt)) have been reported in the literature, focusing on their potential as consolidants on different artifacts of cultural heritage [2, 5]. But one of the most challenging nanomaterial is Ca10(PO4)6(OH)2 hydroxyapatite (HAP), already applied in a large variety of technological and biomedical applications, mainly due to its close relationship with mineral component of hard human tissues [6-7], and in cultural heritage conservation used for carbonate stone consolidation [2]. HAP can be applied for the consolidation of limestones, marbles and sandstones with different carbonate contents. This product is not introduced directly into stone material, but it comes from the reaction between phosphate ions from an aqueous solution of diammonium hydrogen phosphate applied to the stone and calcium ions coming from substrate. Among its advantages, HAP has a similar crystal structure and close lattice parameters of CaCO3 calcite, the main constituents of marbles and limestone. Thanks to its low viscous nature, this aqueous consolidant product is able to penetrate deeply into the stone, generating a significant improvement in mechanical properties of the same stone. The HAP has been tested as a protective treatment for marble against acid rain corrosion [8]. The study of compatibility and adaptability requires that the physical and chemical properties of both consolidator products and stone substrate are well known. Such a knowledge plays a very important role for the good outcome of the present project. Materials of interest, synthesized in our labs has been analysed by using: 1) X-ray diffraction (XRD), effective on crystalline materials and able to carry out information on chemical composition, size, shape and atomic structure, 2) small- and/or wide-angle scattering (SAXS/WAXS), powerful tool to investigate the domain of phosphate particles as a function of their optical properties; in the case of SAXS the technique can be applied to HAp nanoparticles characterization; 3) Fourier-Transform Infrared (FTIR) spectroscopy, reliable techniques for investigating hydroxyl anions and variations within anionic and cationic groups in the obtained materials; 4) scanning electron microscopy for checking morphologies of nanonparticles; 5) biological evaluation of the antimicrobial properties of obtained HAp materials, through direct contact and disc diffusion methods versus most common gram + and gram - bacteria present in human or animal biosystems 6) Laser Induced Breakdown Spectroscopy (LIBS), a non-destructive technique able to get quali-quantitative informations on museal artifacts. 1 - Pesce C., Moretto L.M., Orsega E.F., Pesce G.L., Corradi M., Weber J. Effectiveness and Compatibility of a Novel Sustainable Method for Stone Consolidation Based on Di-Ammonium Phosphate and Calcium-Based Nanomaterials. Materials 12 (2019) 3025. 2 - David, M.E., Ion, R.-M., Grigorescu, R.M., Iancu, L., Andrei, E.R. Nanomaterials Used in Conservation and Restoration of Cultural Heritage: An Up-to-Date Overview. Materials 13 (2020) 2064. 3 - Reyes-Estebanez, M., Ortega-Morales, B.O., Chan-Bacab, M., Granados-Echegoyen, C., Camacho-Chab, J.C., Pereanez-Sacarias J.E., Gaylarde C. Antimicrobial engineered nanoparticles in the built cultural heritage context and their ecotoxicological impact on animals and plants: a brief review. Heritage Science 6 (2018) 52. 4 - El Bakkari M, Bindiganavile V, Boluk Y. Facile Synthesis of Calcium Hydroxide Nanoparticles onto TEMPO-Oxidized Cellulose Nanofibers for Heritage Conservation. ACS Omega 4 (2019) 20606-20611. 5 - Dida B., Siliqi D., Baldassarre, F., Karaj D., Hasimi A., Kasemi V., Nika V., Vozga I. “Nanomaterialet per Konservimin e Trashegimise Kulturore”, SHLBSH, Tirana (2020), ISBN 978-99943-2-468-2 6 - Rakovan J.R., Pasteris J.D. A technological gem: Materials, Medical, and Environmental Mineralogy of Apatite. Elements 11 (2015) 195-200. 7 - Baldassarre F., Altomare A., Corriero N., Mesto E., Lacalamita M., Bruno G., Sacchetti A., Dida B., Karaj D., Della Ventura G.D., Capitelli, F., Siliqi, D. Crystal Chemistry and Luminescence Properties of Eu-Doped Polycrystalline Hydroxyapatite Synthesized by Chemical Precipitation at Room Temperature. Crystals 10 (202) 250. 8 - Graziani G., Sassoni E., Franzoni E., Scherer G.W. Hydroxyapatite Coatings for Marble Protection: Optimization of Calcite Covering and Acid Resistance. Applied Surface Science 368 (2016) 241-257.

Calcium carbonate-based hollow or porous particles are one of the preferred carriers for fabrication of drug delivery systems. We have developed an eco-friendly method to produce calcium carbonate nanocrystals, which have shown biocompatibility and optimal capacity to across cell membrane in human cell lines providing new tools in cancer therapy. The success of drug delivery systems has paved the way for the development of systems for controlled release of agrochemicals. In this work, we exploited calcium carbonate nanocrystals as carriers for targeted release of phytodrugs investigating a potential control strategy for the pathogen Xylella fastidiosa. This pathogen is the causal agent of the Olive Quick Decline Syndrome that is an unprecedented emergency in Italy and potentially in the rest of Europe. We studied nanocrystals interactions with bacteria cells and the application in planta to verify olive plants uptake. Ultrastructural analysis by electron microscopy shown an alteration of bacteria wall following nanocrystals interaction. Nanocrystals were adsorbed from roots and they translocated in plants tissues. Calcium carbonate carriers were able to encapsulate efficiently two types of antimicrobial substances and the potential efficacy was tested in experiment under greenhouse conditions.