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Il telerilevamento ottico è uno strumento validato per il rilevamento, il monitoraggio e lo sviluppo di una migliore comprensione dello stato dei laghi. Tuttavia, non può essere utilizzato in caso di copertura nuvolosa rendendo così difficile la caratterizzazione spaziale e temporale delle fioriture algali per un'analisi ecologica completa. Proponiamo quindi un approccio sinergico che coinvolge immagini ottiche e immagini SAR per monitorare la proliferazione di cianobatteri algali nella Laguna dei Curi (Lituania-Russia). Le immagini satellitari sono fornite dai satelliti Sentinel-1,-2 e -3.

Poster at LPS 2019, Milan Aims This study presents the application of integration of satellite remote sensing and in situ monitoring from optical sensors for assessing phytoplankton dynamics in Lake Trasimeno (Italy). The products are exploited to provide spatial and temporal information of chlorophyll-a concentrations (Chl-a) for both supporting the Water Framework Directive (EC/2000/60), and for evaluating seasonal trends and their possible relations with climate change.

The paradox of the world’s foremost oil exporting country struggling to provide enough energy for itself is by now well known. On the face of it, it does not make much sense to spend time prioritizing alternative approaches: whether consumption should be reined in or alternative sources of electricity developed; or whether among the latter, priority should be given to renewables or nuclear. All of the above need to be pursued in parallel: hence my argument is not that nuclear power should be preferred to other solutions, but simply that it is likely to be part of the solution.

The stability under dynamic mechanical solicitation and with the temperature of the elastomagnetic composite made of Sm2Co7 particles embedded in a silicone matrix is investigated. The thermal stability was examined by DSC measurements. The thermal (up to congruent to 340 degrees C) and mechanical ageing effects on the material elastomagnetic response were investigated by measuring the amplitude, V-0, of the electromotive force induced in a pick-up coil during the dynamic mechanical solicitation of the sample. It was found that for the whole investigation range of temperatures, the V, dependence on the frequency, v, and amplitude, D, of the externally induced deformation is linear and its amplitude is not changing for treatments up to 150 degrees C; for higher temperature treatments the response amplitude is decreasing. The analysis of the response signal (registered at 1 h intervals) after dynamic mechanical solicitation carried out during 48 h, shows the excellent output reliability and no decrease in amplitude with time.

Previous investigations have shown that the signal transducers and activators of transcription (STATs) signaling pathway play an important role in the modulation of apoptosis after ischemia and reperfusion. The mechanism for this enhanced cardioprotection is unknown, but we believe that alterations STATs may play a role. To investigate this hypothesis, we examined the effects of angiotension II type 1 (AT1) and angiotension II type 2 (AT2) receptor antagonist added to cardioplegia on the downstream response of different STATs, connected with proinflammatory pathways (STAT2, STAT5) and prohypertrophic and antiapoptotic pathways (STAT3). Isolated, nonworking hearts (n = 3 per group) from neonatal rats were perfused aerobically (4°C) for 20 min in the Langendorff mode with the modified St. Thomas' Hospital no. 2 (MSTH2) cardioplegic solution (Group 1), the MSTH2 cardioplegic solution + AT1 receptor antagonist (Group 2), and MSTH2 cardioplegic solution + AT2 receptor antagonist (Group 3). Thus, myocytes were isolated by enzymatic digestion, and STAT2, STAT3, and STAT5 were investigated in Western blot studies. Times to arrest after cardioplegia were 8-12 s for all groups. Total cardioplegia delivery volume was about 300 mL for the 20 min. Perfusion with the MSTH2 cardioplegic solution supplemented with AT1 receptor antagonist (Group 2) induced a significant reduction in STAT2 and STAT5 tyrosine phosphorylation (-58 and -63%, respectively, vs. Group 1, P0.05). Conversely, STAT2 and STAT5 activation were unaffected by perfusion with the MSTH2 cardioplegic solution supplemented with AT2 receptor antagonist (Group 3). The decreased activation of STAT2 and STAT5 observed in Group 2 was accompanied by reduction of interleukin-1β (-57% in Group 2 vs. Group 1, P0.05). There were no significant differences in STAT3 phosphorylation among all groups. Only the addition of AT1 receptor antagonist to MSTH2 cardioplegia significantly decreases the inflammatory response of the neonatal rat cardiomyocytes without affecting antiapoptotic influence provided by tyrosine phosphorylation of STAT3. AT1 receptor antagonist added to cardioplegia represents an additional modality for enhancing myocardial protection during cardiac surgery and could contribute to optimize the ischemia tolerance of the pediatric heart.

Optimal surgical timing and operative technique in the treatment of acute cholecystitis are of major importance and are still debatable issues. We report the results of our study on the timing of surgery in a consecutive series of 163 patients treated in the emergency setting for acute cholecystitis over the period from 1998 to 2008. Early surgery and the partially downwards laparoscopic cholecystectomy technique provide a safe and effective way of treating these patients and preventing major complications. The mean time period between onset of symptoms and surgery was 69.2 hrs, with a median value of 53 hrs. The mean operative time was 63.9 min, with a conversion rate of 0.6% and a specific complication rate of 1.22%. The mean postoperative hospital stay was 3.2 days. The timing of surgery (measured in hours) and operative time (measured in minutes) were recorded and analysed to verify whether or not there was a statistically significant relationship between these two variables and establish the best timing for surgery. Our results show a linear relationship between operative time and the timing of surgery. Moreover, at the cut-off point of 57 hrs, the later subgroup (over 57 hrs) had a two-fold increase in operative time compared to the earlier subgroup. At more than 60 hrs approximately from the onset of symptoms, the pathological changes in the surgical target begin, with increasing rapidity, to present a troublesome challenge to the surgeon, making laparoscopic cholecystectomy for acute cholecystitis more difficult and less safe than when performed earlier.

Malnutrition is common in patients on hemodialysis and is a strong predicor of morbidity and mortality. Much progress has been made in recent years in identifying the causes and pathogenesis of malnutrition in hemodialysis patients as well as in recognizing the link between malnutrition and morbidity and mortality. Nevertheless, there is no consensus concerning its management. Conventional interventions such as nutritional counseling, oral nutritional supplements and intradialytic parenteral nutrition and novel preventive and therapeutic strategies such as appetite stimulants, growth hormone, androgenic anabolic steroids, and antiinflammatory drugs have been tested with contradictory and inconclusive results. Malnutrition still remains an important challenge for the nephrologist in the third millennium.

In the treatment of acute cholecystitis the optimal timing of operation, regardless of whether performed laparoscopically or conventionally, is of major importance and not yet well defined feature among the different authors. We report our study on the timing of surgery in a consecutive series of 133 patients.The surgical technique consists in a partially downwards cholecystectomy from the infundibulum to the cystic duct. The dissection never involves the Calot Triangle's structures; this provides a safe and effective way to prevent major complications procedure related. Length of time interval from the onset of symptoms to surgery (ST measured in hours) and operating time (OT measured in minutes) have been recorded and analyzed to find out how these two variables are each other linked and what is the best timing for surgery. We also split the series taking a progressively increasing of ST as a cut off point and analyzed the two derived subgroups to outline which was the time of surgery (period of ST) that provided the best result in term of worsening of laparoscopic procedure difficulty.51.3 hrs of average time between the onset of symptoms and surgery has been reported, with minimum of 24 hrs and maximum of 90 hrs, and median value of 48 hrs. The curve fit analysis on the scatterplot of the variable ST (independent) and OT (dependent) shows that these two variables are directly each other linked. The best division of the series was at the cut off of 57 hrs; each subgroup reached a statistical correlation coefficient: the late subgroup (the one over the cut off time of 57 hrs) had a twofold operating time increasing respect to the early group.Our results outline that there is a linear relationship between the technical difficulties, expressed in term of operating time, and time intervals from the onset of symptoms to surgery. At the cut off time of 57 hrs of interval from the onset of symptoms to surgery, the linear regression coefficient that links the dependent variable OT to the independent variable ST changes increasing up to 1,92. Over 60 hrs from the onset of symptoms the pathological changes of the surgical target becomes more and more quickly a troublesome challenge to the surgeon, letting the laparoscopic cholecystectomy for AC more difficult and less safe than that performed early.

Hemodiafiltration (HFR) with on-line regeneration of the ultrafiltrate, a technique of hemodiafiltration in which the ultrafiltrate passes through a cartridge containing uncoated charcoal, has been shown to be safe, simple, and well tolerated and has been claimed to improve nutritional status or to prevent its deterioration while decreasing the inflammatory response via a reduced production of proinflammatory cytokines. The purpose of the present prospective study was to ascertain whether HRF improves the nutritional status, reduces microinflammation, and decreases serum beta2-microglobulin levels in patients with end-stage renal disease (ESRD).Eight patients, four males and four females, with a mean age of 49.4 +/- 16.8 years, stable on hemodialysis over a period of 8.7 +/- 6.1 years and on standard 4-4.5 h three-times-a-week bicarbonate hemodialysis, were switched to three-times-a-week, 4-h HFR. At baseline and every two months for 12 months at mid-week, serum levels of urea, creatinine, albumin, total cholesterol, C-reactive protein, fibrinogen, complement, ferritin, beta2-microglobulin, intact parathyroid hormone (PTH), hemoglobin concentrations, and hematocrit and the EPO weekly dose were determined. At baseline and at the end of the study, the Malnutrition Inflammatory Score (MIS) was calculated.Nutritional and inflammatory parameters remained constant during the 12-month period of the study. After 12 months of HFR, the MIS trended to be lower, but the difference was not statistically significant. Serum beta2-microglobulin and PTH levels remained constant during all time intervals. Neither hematocrit nor hemoglobin changed over the course of the study as well as the weekly EPO dose.The change from bicarbonate hemodialysis to HFR was safe and well tolerated but was not associated with an improvement of nutritional and inflammatory parameters or a reduction of serum beta2-microglobulin levels.

The biomimetic method was used in order to deposit, on titanium substrates, an hydroxyapatite (HA) coating. The bioactive HA layer was obtained by using, in the first stage of the process, a glass having the composition 2.5CaO.2SiO(2) different from the one proposed for the application of the biomimetic method. This glass can be obtained via sol-gel, a method that allows one to obtain, easily, very pure products. The growth of HA crystals was confirmed by Fourier transform infrared, SEM, EDS and X-ray photoelectron spectroscopy (XPS) results. The experimental results suggest that, as reported in the literature for other supports, the silicate ions released from the glass in the first stage bind themselves to the titanium support. In particular, from XPS analysis it is evident that the titanium substrate is well covered by a calcium phosphate layer of the type of HA.

BACKGROUND: The use of interferon-alpha (IFN-alpha) to treat viral hepatitis C (HCV) occurring in kidney transplant recipients is controversial. This study reports an HCV patient successfully treated with IFN-alpha therapy achieving sustained response, negative serum HCV-mRNA and the disappearance of HCV antibodies, without impairment of renal function. METHOD: A young kidney transplant recipient developed a proven HCV infection 70 months post-transplantation. The patient received IFN-alpha therapy, and for a 32-month follow-up period was evaluated clinically, serologically and virologically. RESULTS: IFN-alpha therapy resulted in normal transaminase activities within 2 months. Serum HCV-mRNA was negative after 4 weeks of treatment and is still negative. Ten months after IFN-alpha therapy withdrawal, the enzyme immunoassay revealed that HCV antibodies (HCVAb) were absent in the serum. IFN-alpha therapy was safe, well tolerated and renal function was not impaired

Loss of lean body mass is frequently reported in patients with end-stage renal disease (ES-RD). Inadequate nutrient intake, superimposed illnesses, endocrine disorders, uremia and acidosis are some of the potential causes of muscle depletion. Previous reports on experimental models show that lean body mass depletion results from enhancement of muscle tissue protein catabolism, mainly associated with activation of ATP-ubiquitin-dependent proteolysis. Little is known, however, about the affects on this proteolytic system in ESRD patients on maintenance hemodialysis (HD). The present study was designed to investigate the expression of ubiquitin mRNAs in skeletal muscle of patients with ESRD on maintenance HD.Biopsies from the rectus abdominis muscle were obtained from eight ESRD patients and from six control subjects undergoing surgery for benign disease. Ubiquitin mRNA levels were measured by Northern blotting analysis.Patients with ESRD had mild metabolic acidosis, as a result of chronic intermittent HD. There were no significant differences between HD patients and controls with regard to the 1.2kb polyubiquitin mRNA species (332.9+/-139 vs 324.2+/-60; ns), but the levels of the 2.4 kb mRNA species were significantly lower in HD patients than in controls (1687+/-542 vs 2529.9+/-325, p=0.01). No correlation was observed between ubiquitin mRNA levels and nutritional parameters and degree of acidosis.The present study found that the ubiquitin mRNA levels were not increased in the muscle of stable, mildly acidotic hemodialysis patients.

The histological manifestation of growth-regulating and differentiation-inducing signals in cancer cells is considered as a key component for clinical outcome prediction and commonly defined as tumor differentiation grade. However, the molecular and functional framework underlying this clinical parameter remains poorly understood. Our correlative data display a significant association (P>0.001) between mitochondrial uncoupling protein 2 (UCP2) and tumor grade in primary breast cancer (n=234). Through mechanistic analyses, we show a synergistic link between UCP2 and established cellular pathways in conferring grade-associated functional phenotypes. Here, the application of well to moderately differentiated primary tumor cell lines has enabled direct observation of SMAD recruitment to the UCP2 promoter underlying repression of gene transcription. In contrast, poorly differentiated tumor cells, known to be TGFβ resistant, displayed aberrant UCP2 regulation, and consequently, gene overexpression, which reduced mitochondrial calcium and facilitated the maintenance of mitochondrial membrane potential, thereby significantly decreasing oxidative stress and inhibiting cell death. Conversely, UCP2 silencing in such cells rapidly led to the induction of apoptosis and cell differentiation, concurrent with reduced cell survival and proliferation, confirming gene-specific effects. Demonstration of a biologically driven role for UCP2 dysregulation in promoting multiple characteristics of tumor aggressiveness strongly endorses assessment of gene expression at clinical presentation to augment therapeutic decision-making and improve patient outcome through personalized targeting approaches.

Human histocompatibility (HLA) gene frequencies were studied in the Italian population. A random sample of healthy individuals born in several Italian regions and provinces was studied to estimate HLA-A, -B, -C and -DR gene frequencies using the maximum likelihood method. The goodness of fit to Hardy-Weinberg proportions was evaluated by the likelihood ratio statistics. Different Italian regions and provinces show significant differences in the HLA alleles, providing further evidence for the genetic heterogeneity in the Italian population. This heterogeneity is also displayed by a synthetic geographical representation which uses colour to map the most informative gene differences. Statistically significant gametic associations between HLA-A, -B, -C and -DR loci are reported. The difference between northern and southern Italy and between continental Italy and Sardegna is clearly shown also by their heterogeneous linkage disequilibria.

The Starr-Edwards (S-E) mitral valve, Model 6120, has been widely used in the last three decades. Fatty infiltration and subsequent damage of the silastic ball, a phenomenon termed ball variance, has been described only in the first generation aortic ball-valve prostheses, used until 1965. A case of partial ball fracture in a 6120-Model S-E mitral valve prosthesis, occurring 27 years after implantation and presenting with thromboembolism and progressive valve dysfunction, is described.

Poster at LPS 2019, Milan Aims This study presents the application of integration of satellite remote sensing and in situ monitoring from optical sensors for assessing phytoplankton dynamics in Lake Trasimeno (Italy). The products are exploited to provide spatial and temporal information of chlorophyll-a concentrations (Chl-a) for both supporting the Water Framework Directive (EC/2000/60), and for evaluating seasonal trends and their possible relations with climate change.

Poster at LPS 2019, Milan Aims This study presents the application of integration of satellite remote sensing and in situ monitoring from optical sensors for assessing phytoplankton dynamics in Lake Trasimeno (Italy). The products are exploited to provide spatial and temporal information of chlorophyll-a concentrations (Chl-a) for both supporting the Water Framework Directive (EC/2000/60), and for evaluating seasonal trends and their possible relations with climate change.

Poster at Sentinel-3 Validation Team 2019 The aim of this work is to evaluate Sentinel-3 OLCI in lake waters to map chlorophyll-a concentrations (Chl-a) and to provide spatial and temporal information on phytoplankton dynamics to support the EU Water Framework Directive (EC/2000/60).

The waste-to-wealth strategy is encouraging the design of a plethora of new value-added materials, by exploiting the chemical and biological richness of biowastes. Humic Acids (HA) are mostly intriguing because of their amphiphilic supramolecular associations which are responsible for several assets, such as adsorption ability towards small molecules, metal ion chelation, redox behavior, and antibacterial activity. The molecular combination of HA with semiconductor nanoparticles represents a valuable strategy to obtain nanostructured hybrid materials and interfaces with advanced features. Concurrently, it permits to overcome intrinsic limits of such organic fraction, including poor stability, fast conformational dynamics, or rapid reactivity in aqueous media. Herein, hybrid HA/ZnO nanoparticles are synthetized through a bottom-up strategy, exerting an improved pro-oxidant behavior by generating Reactive Oxygen Species, even without light irradiation, favoring an enhanced photocatalytic and antimicrobial activity against different bacterial pathogens. Several techniques, including SEM/TEM, DLS, ζ-potential, XRD, FTIR, TGA/DSC, EPR and DRUV, allows to define the structure-property-function relationships, thus highlighting the crucial role of a fine conjugation amongst the metal oxide precursor and bioderived fraction to drive the pro-oxidant activity. This study provides strategic guidelines to easily produce low-cost organo-inorganic nanomaterials with redox and biocide properties, aimed at coping environmental and health issues.

Following a waste-To-wealth approach, humic acid (HA) was exploited as a flame retardant additive. The effect of its addition alone and in combination with urea (UR) and ammonium polyphosphate (APP) on the thermal, fire, and mechanical performances of a bisphenol A diglycidyl ether (DGEBA)-based epoxy resin modified with (3-Aminopropyl)-Triethoxysilane (AP) and cured with aliphatic isophoronediamine (IDA) has been investigated. Unlike in previous studies, a UL 94-V-0 classification was achieved for epoxy resin containing HA at 6 wt % and APP at only 1 wt % phosphorus (P) loading. The presence of silicon-modified epoxy chains ameliorated the distribution of the biowaste within the resin, and the addition of HA alone avoided melt dripping. Besides, APP and UR promoted a remarkable reduction (up to 52%) of the peak heat release rate (pHRR) values and a significant delay (up to 21%) of the time to ignition in cone calorimetry tests, and hence an increase (up to 1.8 min) of the time to flashover, without any detrimental effect on the overall mechanical behavior. The evolved gas, thermal, and fire analysis was used to propose the combined mode of action of HA, UR, APP, and silicon in the fire performance improvement of the hybrid epoxy system.

Stimulated Raman scattering in transparent glass-ceramics (TGCs) based on bulk nucleating phase Ba2NaNb5O15 were investigated with the aim to explore the influence of micro- and nanoscale structural transformations on Raman gain. Nanostructured TGCs were synthesized, starting with 8BaO·15Na2O·27Nb2O5·50SiO2 (BaNaNS) glass, by proper nucleation and crystallization heat treatments. TGCs are composed of nanocrystals that are 10–15 nm in size, uniformly distributed in the residual glass matrix, with a crystallinity degree ranging from 30 up to 50% for samples subjected to different heat treatments. A significant Raman gain improvement for both BaNaNS glass and TGCs with respect to SiO2 glass is demonstrated, which can be clearly related to the nanostructuring process. These findings show that the nonlinear optical functionalities of TGC materials can be modulated by controlling the structural transformations at the nanoscale rather than microscale.

Nature mimicking implies the design of nanostructured materials, which can be assembled into a hierarchical structure, thus outperforming the features of the neat components because of their multiple length scale organization. This approach can be effectively exploited for the design of advanced photocatalysts with superior catalytic activity for energy and environment applications with considerable development in the recent six years. In this context, we propose a review on the state of the art for hierarchical photocatalyst production. Particularly, different synthesis strategies are presented, including template-free structuring, and organic, inorganic, and hybrid templating. Furthermore, emerging approaches based on hybrid and bio-waste templating are also highlighted. Finally, a critical comparison among available methods is carried out based on the envisaged application.

Safety parameters assessment is not sufficient to fully understand the flammable and explosive behaviour of a combustible dust and correctly manage potential risk. A correct evaluation requires the identification of flame propagation path as well as the limiting step controlling fire propagation, through evaluation of dimensionless numbers (Biot, Damköhler, Thiele, Sherwood, Thiele modulus numbers). Herein, these aspects were investigated for non-traditional dusts, made of nylon 6,6 short fibers. To this purpose, flammability parameters including minimum ignition energy (MIE), the maximum pressure of explosion and the deflagration index were assessed and combined with results of extensive physical-chemical characterization, by means of several techniques (TGA/DSC, FTIR, XRD). In particular, thermogravimetric analysis highlighted the presence of homogeneous and heterogeneous phase phenomena activated at different temperatures and heating rates. The homogeneous phase processes are controlled by the pyrolysis process strictly dependent on the dust size and its decomposition kinetics. The most flammable sample is characterized by smaller dimensions and a fast decomposition kinetics at low temperature. Heterogeneous flame propagation is controlled by the intrinsic heterogeneous reaction. The most reactive sample is characterized by the highest value of specific surface area and by intense exothermic phenomena at low temperature, as evidenced by the analysis of the solid residue. As a main conclusion, the processes involving nylon fibres that may modify the key parameters influencing the flammable/explosive behaviour are also discussed.

Humic acids (HAs) provide an important bio-source for redox-active materials. Their functional chemical groups are responsible for several properties, such as metal ion chelating activity, adsorption ability towards small molecules and antibacterial activity, through reactive oxygen species (ROS) generation. However, the poor selectivity and instability of HAs in solution hinder their application. A promising strategy for overcoming these disadvantages is conjugation with an inorganic phase, which leads to more stable hybrid nanomaterials with tuneable functionalities. In this study, we demonstrate that hybrid humic acid/titanium dioxide nanostructured materials that are prepared via a versatile in situ hydrothermal strategy display promising antibacterial activity against various pathogens and behave as selective sequestering agents of amoxicillin and tetracycline antibiotics from wastewater. A physicochemical investigation in which a combination of techniques were utilized, which included TEM, BET, 13C-CPMAS-NMR, EPR, DLS and SANS, shed light on the structure-property-function relationships of the nanohybrids. The proposed approach traces a technological path for the exploitation of organic biowaste in the design at the molecular scale of multifunctional nanomaterials, which is useful for addressing environmental and health problems that are related to water contamination by antibiotics and pathogens.

Understanding flame propagation mechanism and thermal behavior of flammable dusts is of crucial importance, since they strongly affect the flammability and explosion parameters. In a previous work, we found that the volatile point of anthraquinone/nicotinic acid mixtures can be lower than the one of the pure dusts, suggesting a synergistic effect. In this work, thermogravimetric and differential scanning calorimetry analyses of anthraquinone/niacin mixtures were carried out both in open and closed cup, to explain the observed synergistic behavior. FTIR analysis on solid residue and evolved gaseous species showed that the mixtures change compositions during the thermal treatment, without undergoing any chemical transformation. The thermal behavior of dust mixtures reveals the presence of a eutectic point, resulting in a volatiles production at lower temperature and accelerating the flame propagation.

Humic acids (HA) exhibit fascinating multifunctional features, yet degradation phenomena as well as poor stability in aqueous environments strongly limit their use. Inorganic nanoparticles are emerging as a powerful interface for the development of robust HA bio-hybrid materials with enhanced chemical stability and tunable properties. Hybrid organic-inorganic SiO2/HA nanostructures were synthesized via an in-situ sol-gel route, exploiting both physical entrapment and chemical coupling. The latter was achieved through amide bond formation between carboxyl groups of HA and the amino group of 3-aminopropyltriethoxysilane (APTS), as confirmed by Fourier-Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. Monodisperse hybrid nanoparticles about 90 nm in diameter were obtained in both cases, yet Electron Paramagnetic Resonance (EPR) spectroscopy highlighted the different supramolecular organization of HA. The altered HA conformation was reflected in different antioxidant properties of the conjugated nanoparticles that, however, resulted in being higher than for pure HA. Our findings proved the key role of both components in defining the morphology of the final system, as well as the efficacy of the ceramic component in templating the HA supramolecular organization and consequently tuning their functional features, thus defining a green strategy for bio-waste valorization.

Glycerol is the main by-product of biodiesel production; its upgrading to more valuable products is a demanding issue. Hydrogenolysis to 1,2-propanediol is one of the most interesting processes among the possible upgrading routes. In this study, we propose novel copper/zirconia catalysts prepared by advanced preparation methods, including copper deposition via metal–organic framework (MOF) and support preparation via the sol–gel route. The catalysts were characterized by N2 physisorption, X-ray diffraction, Scanning Electron Microscopy, H2-TPR and NH3-TPD analyses and tested in a commercial batch reactor. The catalyst prepared by copper deposition via MOF decomposition onto commercial zirconia showed the best catalytic performance, reaching 75% yield. The improved catalytic performance was assigned to a proper combination of redox and acid properties. In particular, a non-negligible fraction of cuprous oxide and of weak acid sites seems fundamental to preferentially activate the selective pathway. In particular, these features avoid the overhydrogenolysis of 1,2-propanediol to 1-propanol and enhance glycerol dehydration to hydroxyacetone and the successive hydrogenation of hydroxyacetone to 1,2-propanediol.

Humic acids (HA) are considered a promising and inexpensive source for novel multifunctional materials for a huge range of applications. However, aggregation and degradation phenomena in aqueous environment prevent from their full exploitation. A valid strategy to address these issues relies on combining HA moieties at the molecular scale with an inorganic nanostructured component, leading to more stable hybrid nanomaterials with tunable functionalities. Indeed, chemical composition of HA can determine their interactions with the inorganic constituent in the hybrid nanoparticles and consequently affect their overall physico-chemical properties, including their stability and functional properties in aqueous environment. As a fundamental contribution to HA materials-based technology, this study aims at unveiling this aspect. To this purpose, SiO2 nanoparticles have been chosen as a model platform and three different HAs extracted from composted biomasses, manure (HA_Man), artichoke residues (HA_Art) and coffee grounds (HA_Cof), were employed to synthetize hybrid HA-SiO2 nanoparticles through in-situ sol-gel synthesis. Prepared samples were submitted to aging in water to assess their stability. Furthermore, antioxidant properties and physico-chemical properties of both as prepared and aged samples in aqueous environment were assessed through Scanning Electron Microscopy (SEM), N2 physisorption, Simultaneous Thermogravimetric (TGA) and Differential Scanning Calorimetric (DSC) Analysis, Fourier Transform Infrared (FT-IR), Nuclear Magnetic Resonance (NMR), Electron Paramagnetic Resonance (EPR) spectroscopies. The experimental results highlighted that hybrid HA-SiO2 nanostructures acted as dynamic systems which exhibit structural supramolecular reorganization during aging in aqueous environment with marked effects on physico-chemical and functional properties, including improved antioxidant activity. Obtained results enlighten a unique aspect of interactions between HA and inorganic nanoparticles that could be useful to predict their behavior in aqueous environment. Furthermore, the proposed approach traces a technological route for the exploitation of organic biowaste in the design of hybrid nanomaterials, providing a significant contribution to the development of waste to wealth strategies based on humic substances.

Hybrid Melanin-TiO2 nanoparticles are promising bioinspired antibacterial agents for biomedical coatings and food-packaging fields. However, due to a very low colloidal stability, they showed a high tendency to self-aggregate and rapidly precipitate, making not easy their use in aqueous medium to produce homogeneous antimicrobial coatings or nanocomposites. A valid strategy to improve their dispersion is the combination with a hydrophilic water-soluble polymer such as poly-vinyl-alcohol (PVA), which is a good choice to improve the colloidal stability of nanoparticles and to modulate their agglomeration. In this work, we propose an in-situ synthetic approach based on the hydrothermal route, by which the hybrid Melanin-TiO2 nanoparticles were prepared starting from the inorganic and organic precursors in the presence of PVA. Combined approach of TEM, XRD, TG/DSC, EPR and DLS techniques allows for assessing the PVA role in the formation of hybrids and on their morphological features as well as colloidal stability and aqueous dispersion. Antibacterial tests demonstrated the biocide activity of PVA/Melanin-TiO2 nanoparticles against Escherichia coli bacterial cultures, which resulted partially influenced by the PVA content. This study provides key information on the mutual influence of organic/inorganic components on the functional properties of the final hybrid nanocomposites, contributing to define a much more far-reaching implementation in the synthesis of bioinspired polymer-based nanocomposites.

One of the emerging research areas at the convergence of physical science, chemistry, engineering, and life science is the development of theranostic nanoagents that integrate therapy and diagnosis for cost-effective precision medicine. Among currently available imaging methodologies, photoacoustic imaging (PAI) is an exciting new modality that uses non-ionizing radiation for real-time imaging with high spatial resolution and penetration depth. Furthermore, PAI could be easily combined with poor invasive cancer therapies, such as Phototermal Ablation. The development of bio-inspired NIR responsive nanomaterials plays a key role in improving sensitivity and signal-to-noise ratio in PAI. To this purpose a promising approach relies on the green synthesis of nanoparticles starting from natural or endogenous materials as a source of contrast. To date, several melanin-based probes have been reported with specific properties for PAI, however, poor solubility in biological fluids as well as poor contrast of photoacoustic signal, if compared to other contrast agents must be addressed. By mimicking natural melanin we reported the first example of stable monodispersed hybrid nanoparticles (MelaSil-NPs) made up of eumelanin biopolymer intimately integrated into a silica matrix. One-pot in-situ templated synthesis strategy was carried out where all components, form together and influenced each other. In particular, metal chelating and reducing properties of melanins towards transition metal ions were exploited to obtain Ag ions reduction (MelaSil_Ag), while at the same time controlling the growth of in-situ generated silver-nanoclusters. Nanostructured SiO2 was employed as templating agent for DHICA polymerization to melanin and a core-shell architecture was obtained, with enhanced photoacoustic signal. Furthermore, hybrid nature of the material allowed a fine control of morphology and stability to aggregation, ensuring cellular uptake and ultimately leading to promising probes for multimodal imaging in cancer diagnosis and therapy.

Developing advanced materials for wound dressings is a very challenging, yet unaddressed task. These systems are supposed to act as temporary skin substitutes, performing multiple functions, including fluid absorption and antimicrobial action, supporting cell proliferation and migration in order to promote the skin regeneration process. Following a global bioinspired approach, in this study, we developed a multifunctional textile for wound dressing applications. Biodegradable polyhydroxybutyrate/poly-3-caprolactone (PHB/PCL) mats were fabricated by electrospinning to mimic the extracellular matrix (ECM), thus providing structural and biochemical support to tissue regeneration. Furthermore, inspired by nature's strategy which exploits melanin as an effective weapon against pathogens infection, PHB/PCL mats were modified with hybrid Melanin-TiO2 nanostructures. These were combined to PHB/PCL mats following two different strategies: in-situ incorporation during electrospinning process, alternately ex-post coating by electrospraying onto obtained mats. All samples revealed huge water uptake and poor cytotoxicity towards HaCat eukaryotic cells. Melanin-TiO2 coating conferred PHB/PCL mats significant antimicrobial activity towards both Gram(+) and Gram(−) strains, marked hydrophilic properties as well as bioactivity which is expected to promote materials-cells interaction. This study is going to provide a novel paradigm for the design of active wound dressings for regenerative medicine.

In this work, experimental results about poly(butylene terephthalate) (PBT) based nanocomposites filled with various amounts of silica nanoparticles (NPs) are reported. Two different types of filler are used: silica gel NPs, produced through the Stöber method, and a commercial fumed silica, both coated by a PBT shell. Melt-mixed samples have been thoroughly investigated by scanning and transmission electron microscopy, infrared Fourier transform spectroscopy (FTIR), thermal gravimetric analysis, differential scanning calorimetry, wide and small angle X-ray diffraction, and dynamic mechanical analysis. A fine and very good dispersion of NPs into the polymeric matrix is revealed through the morphological analysis when Stöber NPs were used as filler with respect to systems including commercial fumed silica particles. This evidence, combined with matrix-filler interactions revealed by FTIR spectroscopy, justifies the enhancement of both storage modulus and glass transition temperature of the former samples in comparison with reference pristine PBT. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46006.

A new metallic glass alloy characterized by high amplitude of magnetoelastic waves was synthesized. X-ray spectra evidenced the amorphous structure in the as-cast material, while differential thermal analysis confirmed the metastable initial phase and the occurrence of several crystallization peaks. The alloy shows a high difference between the glass transition and crystallization temperatures. Several heat treatments were performed and the structural relaxation effects were shown by means of the behavior of magnetization, Curie temperature and the resonant magneto-elastic wave amplitude. The strong increase of the last parameter, induced by the occurrence of the amorphous structure, is the most important result for application. Magnetic and magneto-elastic properties deteriorate if crystallization occurs, but in the optimal condition a partial nanocrystallisation may be present.