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PurposeAs a discipline in its infancy, online adaptive RT (ART) needs new ontologies and ad hoc criteria to evaluate the appropriateness of its use in clinical practice. In this experience, we propose a predictive model able to quantify the dosimetric impact due to daily inter-fraction variability in a standard RT breast treatment, to identify in advance the treatment fractions where patients might benefit from an online ART approach.MethodsThe study was focused on right breast cancer patients treated using standard adjuvant RT on an artificial intelligence (AI)-based linear accelerator. Patients were treated with daily CBCT images and without online adaptation, prescribing 40.05 Gy in 15 fractions, with four IMRT tangential beams. ESTRO guidelines were followed for the delineation on planning CT (pCT) of organs at risk and targets. For each patient, all the CBCT images were rigidly aligned to pCT: CTV and PTV were manually re-contoured and the original treatment plan was recalculated. Various radiological parameters were measured on CBCT images, to quantify inter-fraction variability present in each RT fraction after the couch shifts compensation. The variation of these parameters was correlated with the variation of V95% of PTV (ΔV95%) using the Wilcoxon Mann–Whitney test. Fractions where ΔV95% > 2% were considered as adverse events. A logistic regression model was calculated considering the most significant parameter, and its performance was quantified with a receiver operating characteristic (ROC) curve.ResultsA total of 75 fractions on 5 patients were analyzed. The body variation between daily CBCT and pCT along the beam axis with the highest MU was identified as the best predictor (p = 0.002). The predictive model showed an area under ROC curve of 0.86 (95% CI, 0.82–0.99) with a sensitivity of 85.7% and a specificity of 83.8% at the best threshold, which was equal to 3 mm.ConclusionA novel strategy to identify treatment fractions that may benefit online ART was proposed. After image alignment, the measure of body difference between daily CBCT and pCT can be considered as an indirect estimator of V95% PTV variation: a difference larger than 3 mm will result in a V95% decrease larger than 2%. A larger number of observations is needed to confirm the results of this hypothesis-generating study.

Magnetic chitosan nanoparticles, synthesized by in situ precipitation, have been used as adsorbents to remove sulfamethoxazole (SMX), a sulfonamide antibiotic dangerous due to its capacity to enter ecosystems. The adsorption of SMX has been carried out in the presence of tertiary wastewaters from a depuration plant to obtain more realistic results. The effect of pH on the adsorption capacity significantly changed when carrying out the experiments in the presence of wastewater. This change has been explained while taking into account the charge properties of both the antibiotic and the magnetic chitosan. The composition of wastewaters has been characterized and discussed as regards its effect on the adsorption capacity of the magnetic chitosan. The models of Elovich and Freundlich have been selected to describe the adsorption kinetics and the adsorption isotherms, respectively. The analysis of these models has suggested that the adsorption mechanism is based on strong chemical interactions between the SMX and the magnetic chitosan, leading to the formation of an SMX multilayer.

Use of novel alternative compounds in agriculture is being promoted to reduce synthetic pesticides. An in vitro study was conducted to evaluate antimicrobial and antioxidant activities of chitosan hydrochloride (CH) and COS (chito-oligosaccharides)-OGA (oligo-galacturonides) at concentrations of 1%, 0.5%, 0.25%, 0.1%, 0.05%, and 0.025%. COS-OGA at 1% and 0.5% concentrations completely inhibited mycelial growth of Alternaria alternata, Alternaria brassicicola, Botrytis cinerea, Monilinia laxa, Monilinia fructigena, and Monilinia fructicola. Further, complete inhibition was observed with 0.25% COS-OGA for M. fructigena and M. laxa. Inhibition for B. cinerea, M. fructicola, A. alternata, and A. brassicicola at 0.25% COS-OGA was 86.75%, 76.31%, 69.73%, and 60.45%, respectively. M. laxa and M. fructigena were completely inhibited by CH concentrations of 1–0.25% and M. fructicola by concentrations of 1–0.5%. At CH 0.25%, inhibition for M. fructicola, A. brassicicola, A. alternata, and B. cinerea was 93.99%, 80.99%, 69.73%, and 57.23%, respectively. CH showed effective antibacterial activity against foodborne Escherichia coli. COS-OGA had higher antioxidant activity than CH when assessed by DPPH and hydroxyl radical scavenging assays. Our findings offer insights into the antimicrobial efficacy and mechanisms of action of these novel compounds, which have the potential to serve as alternatives to synthetic pesticides. In vivo investigations are required to validate the prospective application of these treatments for pre- and postharvest disease management.

Methanol is expected to be a possible solution for reducing global greenhouse gas emissions and minimizing the dependency on fossil fuels. This paper presents a systematic approach of methanol (MeOH) production from industrial waste gases including flue gas (FG) and coke oven gas (COG) that are considered an important threat to the environment. The impact of process parameters, including dimensional parameters (length, diameter, and number of tubes) and operational parameters (reactor temperature, pressure, and thermal fluid temperature) over the MeOH synthesis, are investigated by Aspen Plus. Firstly, the synthesis process is designed and optimized using syngas (SG) as a feed material. Secondly, by replacing the feed material with FG and COG, methanol production variability is investigated and demonstrated for the same optimized process. Afterward, an efficient heat exchange network system is developed for all three different processes using Aspen Energy Analyzer. The optimized dimensional parameters of the MeOH synthesis reactor are determined to be a length of 12 m, a diameter of 0.06 m, and 5000 tubes for achieving a conversion rate of 75%. Meanwhile, the optimized operational parameters are identified as a reactor temperature of 209 °C, reactor pressure of 70 bar, and thermal fluid temperature of 196 °C. Furthermore, the influence of the stoichiometric number (SN) on the process was observed with higher SN values resulting in increased hydrogen (H2) concentration and an improved forward reaction of MeOH synthesis, leading to higher conversion rates. The findings and insights gained from this study can serve further improvements and advancements in MeOH synthesis processes.

A significant bottleneck for the industrial application of lipases stems from their poor stability in the presence of commercial triglycerides. This is mainly due to the inactivating effect of the products of triglyceride oxidation (PTO), which are usually produced when oils and fats, being imported from far countries, are stored for long periods. In this study, the immobilization of a lipase from Candida rugosa on chitosan hydrogels has been carried out following two alternative approaches based on the enzyme adsorption and entrapment to increase the lipase stability under the operating conditions that are typical of oleochemical transformations. The effect of model compounds representing different classes of PTO on a lipase has been studied to optimize the enzyme immobilization method. Particular attention has been devoted to the characterization of the inactivating effect of PTO in nonaqueous media, which are adopted for most industrial applications of lipases.

Bubbling fluidized bed (BFB) reactor is advantageous for synthesis gas or syngas production among other available gasifiers. In this study, a BFB gasifier has been designed, utilizing non-woody biomass (rice straw) and air as gasifying medium, to investigate the effect of equivalence ratio (ER), static bed height, and operating temperature on synthesis gas yield and gasification efficiency. To calculate various structural and operating parameters, a reaction chamber with a diameter of 10 cm and a bed material of 400-500 µm has been studied. Considering the minimum fluidization velocity, slugging velocity, and terminal velocity, the optimum operating velocity has been taken as 17.25 cm/s. The calculated optimum transport disengagement height (TDH) is 86 cm, and the freeboard height is approximately 116 cm. Thus, the overall height of the reactor has come up as 202 cm. Almost 80% carbon conversion efficiency (CCE) was achieved from this BFB reactor with an optimum ER value of 0.35 during rice straw gasification. The same gasifier results in a synthesis gas yield of 3.6 Nm 3 kg with a lower heating value (LHV) of about 3.5 MJ Nm 3 at optimum ER value. Further scaling up this process based on the findings of this study for industrial-scale synthesis gas production can pave a way for bioenergy generation from non-woody biomass.

Dyes are considered as one the most important classes of contaminants that threaten the environment and human life. The synergy between the adsorption capacity of chitosan hydrogels and the catalytic properties of the enzyme laccase was exploited to improve the removal of contaminants from a liquid stream. The adsorption capacity of a chitosan hydrogel was tested on three different textile dyes. The effect of pH on the adsorption efficiency was dependent on the dye tested: the removal of methylene blue (MB), a cationic dye, was more effective at alkaline values of pH, whereas bromophenol blue (BPB) and Coomassie brilliant blue (BB), both anionic dyes, were more effectively removed under acid environments. The use of laccase immobilized onto chitosan has significantly improved the efficiency of dye removal, exploiting the synergy between the adsorption capacity of chitosan and the catalytic properties of the enzyme. The simultaneous processes of adsorption and enzymatic degradation improved the dye removal whatever the pH value adopted, making the removal efficiency less dependent from the pH changes. The chitosan used as a support for the immobilization of laccases showed good stability under repeated cycles, demonstrating the feasibility of the method developed for the application in wastewater remediation.

Hybrid materials based on amorphous titanium or zirconium oxide with specific organic ligands show oxidative activity toward organic pollutants in the dark, owing to the generation and unusual long-term adsorption of superoxide radical anions on their surfaces. Here an overview of perspectives for the development of these materials and their processing towards technological applications is presented, focusing on the TiO2-acetylacetonate system. First, the tuning and optimization of the sol-gel synthesis conditions is discussed, aimed at yielding the desired products, such as chemical gels or stable sols. Then the thermal stability of the hybrid dried gels is assessed, in relation to their ability to form superoxide radicals. Finally, electrospinning is introduced as an efficient and ecofriendly technique to support the xerogel powders embedding them in a porous nanofiber polymer network. The preliminary characterization of the electrospun composite polyvinylpyrrolidone-hybrid TiO2 reveals potentialities for the realization of air filters or antimicrobial gauzes.

Immobilized enzymes are increasingly used in enzymatic microreactors, to encourage applications in different fields: food industry, medical diagnostics, organic synthesis, drug discovery, biosensors. As a matter of facts, microfluidic systems offer many advantages over conventional packed-bed bioreactors, such as higher efficiency, feasibility of multi-enzyme systems, higher mechanical stability, reduced amounts of reagents required [Pirozzi et al., 2016]. In this study ß-1,4-xylan obtained from hemicelluloses was used to obtain xylo-oligosaccharides (XOS), the only nutraceutical that can be produced from lignocellulosic biomass. XOS are considered non-digestible food ingredients, and their prebiotic effect of XOS on Bifidobacterium and Lactobacillus species has been recently demonstrated [Aachary et al., 2011; Broekaert et al., 2011; Nacos et al., 2006; Samanta et al, 2015; Vazquez]et al., 2000]. In addition XOS are stable at wide range of pH (2.5–8.0) and temperature (100 °C), they can stimulate the selective growth of the gut microflora, reduce the blood glucose and cholesterol, reduce the pro-carcinogenic enzymes in gastrointestinal tract, and enhance the mineral absorption from large intestine [Aachary et al., 2011; Broekaert et al., 2011; Nacos et al., 2006; Samanta et al, 2015; Vazquez]et al., 2000]. In this view, sol-gel methods were used for the physical entrapment of xylanase from T. lanuginosus. Due to the mild conditions usually adopted for the gel synthesis, enzymes could be added to the initial mixture of precursors and so entrapped within monolithic porous layers in capillary tubes [Pirozzi et al., 2016]. A suitable combination of sol-gel precursors was found for the simultaneous improvement of the monolith adhesion to the tubing internal surfaces and of the catalytic properties of the entrapped enzymes. Specific attention was devoted to the determination of operating conditions suitable to enhance enzyme stability as well as selectivity in terms of XOS produced.

Biohydrogen is considered a promising biofuel of strategic interest characterized by high energy content per mass unit, easiness in producing electricity through fuel cells, a process that produces water as the only by-product. Among the bioprocesses aimed at biohydrogen production, dark fermentation is gaining a worldwide interest for being both environmental friendly and relatively efficient. In this perspective, food waste represents a good substrate for biohydrogen production through dark fermentation, being made of biodegradable organic matter and nutrients essential for the growth of microorganisms driving this process. In this study, biohydrogen production through a mesophilic batch dark fermentation (37 °C) was performed. The effect of the progressive adaption of the inoculum on the food waste feedstock was evaluated. Both the liquid and the gas phases produced during the incubation were analyzed. Microbial biomass, pH, biogas volume and composition were also monitored. Biohydrogen yields increased with progressive inoculum acclimation to the food waste, reaching about 35 mL/gVSFW in 3 days of dark fermentation, with an average biohydrogen in the biogas produced of 55 %, corresponding to a theoretical energy recovery of about 34 kWh for 1 ton of food waste.