Investigation on synthesis of ternary g-C3N4/ZnO-W/M nanocomposites integrated heterojunction II as efficient photocatalyst for environmental applications

The rapid industrialization of the world is disparagingly manipulating our environment and natural ecosystem. The researchers are taking keen interest to invent novel material as photocatalyst for non-degradable organic pollutants. Solar energy-driven practices employing semiconductors are a novel approach towards wastewater remediation. Here in, we successfully synthesized a vigorous photocatalysts comprising of g-C₃N₄ and doped ZnO-W/M (M = Co, Ce, Yb, Sm) by co-precipitation followed by metals doping via calcination approach. The structural, morphological, and photocatalytic applications for organic pollutants of synthesized heterostructure nanocomposites were examined by XRD, FTIR, SEM, EDX and UV visible spectrophotometer. Diffraction peaks attributed to both g-C₃N₄ and ZnO-W were detected in the XRD spectra. The FTIR spectra also inveterate the formation of g-C₃N₄/ZnO-W/M composites. The SEM images reveal an agglomerated morphology and EDS analysis also confirmed close contact between g-C₃N₄, ZnO-W and doped metals. The abridged energy band gap of g-C₃N₄/ZnO-W/M (M = Ce, Yb, Sm, Co) nanocomposites calculated via Tauc plot are 2.68, 2.88, 3.24 and 3.29 eV respectively. Narrowing of bandgap is considered an imperative triumph for the degradation of industrial effluents. The photocatalytic activity was performed against four different dyes and follows the trend Ce > Yb > Sm > Co. The recyclability tests were carried out for different dyes and no substantial catalytic activity loss was observed even after the fourth experimental run, which proves that reported ternary heterojunctions exhibit high mechanical stability and reusability.The species trapping experiment exposed that generated h⁺ are the principal active specie for dye photodegradation reactions. This work disseminates a novel photocatalyst for the removal of synthetic dyes.

Sustainable production of pharmaceutical, nutraceutical and bioactive compounds from biomass and waste

The aim of this tutorial review is to provide a general overview of processes, technologies and challenges in the production of pharmaceutical and bioactive compounds from food waste and lignocellulosic residues. Particular attention is given to benign-by-design processes instinctively devoted to environmental sustainability for the recovery of bioactive compounds from food waste as well as for the production of alcohols, acids, polyols, furans and aromatic compounds from lignocellulosic residues. At the same time, novel green synthetic routes for the production of active pharmaceutical ingredients and the development of novel bioactive compounds are discussed. Recent success industrial stories on the use of food waste and lignocellulosic residues for pharmaceutical and nutraceutical applications are also discussed.

Electrospun Nanofibers and Electrochemical Techniques for the Detection of Heavy Metal Ions

Contamination by heavy metals is currently one of the most environmental concerns especially due to the toxicity, pervasiveness, and persistence of these substances. As they are not biodegradable, heavy metals are harmful not only for water, air, and soil but also for human health, even in very low traces. There is therefore a pressing need to develop an efficient, economic, and rapid analysis method to be applied in a wide range of conditions and able to detect very low contaminants concentrations. Currently, the most novel solution in this field is represented by the combination of electrospun nanofibers and highly sensitive electrochemical techniques. It has been proved that nanofibers, due to their outstanding properties, perfectly fit as sensing material when trace concentrations of heavy metals were investigated by anodic stripping voltammetry, envisaged as the most sensitive electrochemical technique for this kind of measurements. This work aims to provide an overview of the latest trends in the detection of contaminants by the simultaneous use of electrospun fibers and anodic stripping voltammetry. Indeed, a clear and comprehensive vision of the current status of this research may drive future improvements and new challenges.

Integral valorization of orange peel waste through optimized ensiling: Lactic acid and bioethanol production

The management of the huge amount of orange peel waste (OPW) is a complex issue although it has a very high potential in terms of biorefining. One of the main problems in the valorisation of OPW is the seasonality of its production with the ensiling method being largely proposed as a possible solution. During the ensiling process, value added chemicals including lactic acid, acetic acid and ethanol are spontaneously produced together with a significant loss of volatile solids (VS) . In this contribution, the stimulation of lactic acid bacteria by either a biological (inoculation with leachate coming from a previous ensiling process) or chemical (MnCl₂ supplementation) methods has been tested with the aim to increase the chemicals production preventing, at the same time, the VS loss. The inoculation with the leachate improves both the VS recovery (+7%) and the concentration of lactic acid (+113%) with respect to the uninoculated one (control). The overall yields of the process are noticeable, up to about 55 g·kg_TS^-1 of lactic acid, 26 g·kg_TS^-1 of acetic acid and 120 g g·kgTS-1 of ethanol have been produced. On the other hand, the chemical stimulation enhances the production of liquid products together with a significant VS loss. The proposed preservation method, due to its simplicity, can be easily implemented at full-scale allowing the production of added-value chemicals and the concurrent storage of the OPW that can be further valorised (e.g. animal feed, pectin or biomethane production).

Alexithymia and obesity: controversial findings from a multimethod assessment

OBJECTIVE

The aim of the study is to assess alexithymia levels in obese patients using a multimethod measurement (TAS-20 and TSIA) to evaluate both possible differences between the two instruments and their relationship with body weight.

PATIENTS AND METHODS

54 obese patients, seeking surgical treatment, were enrolled. They completed a socio-demographic questionnaire, 20-items Toronto Alexithymia Scale and the Toronto Structured Interview for Alexithymia.

RESULTS

Data analysis showed a significant positive association between TAS-20 and TSIA total scores (r=.28, p<.05), but only the TSIA score was positively related to body weight (r=.39; p<.001). Multivariable linear regression models showed the predictive effects of TSIA total score (beta=.41; p<.001) and difficulty in identifying feelings (DIF) (beta=.56; p<.001) respectively on weight.

CONCLUSIONS

The findings showed a different association between body weight and alexithymia according to the instrument employed to evaluate alexithymia, supporting the importance of a multimethod assessment in some clinical conditions.

Recent catalytic routes for the preparation and the upgrading of biomass derived furfural and 5-hydroxymethylfurfural

Furans represent one of the most important classes of intermediates in the conversion of non-edible lignocellulosic biomass into bio-based chemicals and fuels. At present, bio-furan derivatives are generally obtained from cellulose and hemicellulose fractions of biomass via the acid-catalyzed dehydration of their relative C6-C5 sugars and then converted into a wide range of products. Furfural (FUR) and 5-hydroxymethylfurfural (HMF) are surely the most used furan-based feedstocks since their chemical structure allows the preparation of various high-value-added chemicals. Among several well-established catalytic approaches, hydrogenation and oxygenation processes have been efficiently adopted for upgrading furans; however, harsh reaction conditions are generally required. In this review, we aim to discuss the conversion of biomass derived FUR and HMF through unconventional (transfer hydrogenation, photocatalytic and electrocatalytic) catalytic processes promoted by heterogeneous catalytic systems. The reaction conditions adopted, the chemical nature and the physico-chemical properties of the most employed heterogeneous systems in enhancing the catalytic activity and in driving the selectivity to desired products are presented and compared. At the same time, the latest results in the production of FUR and HMF through novel environmental friendly processes starting from lignocellulose as well as from wastes and by-products obtained in the processing of biomass are also overviewed.

Strategies for the sustainable management of orange peel waste through anaerobic digestion

The processing of oranges is a major industry worldwide and leads to the production of large amounts of orange peel waste (OPW). Energy production through anaerobic digestion of OPW is a promising option; however, the high content of essential oil, mainly composed of d-limonene, a well-known antioxidant, can cause the inhibition of the biological activity. In this paper, different pretreatment methods were tested (e.g. ensiling, aeration, thermal and alkaline treatments) to optimize the anaerobic digestion of OPW focusing on d-limonene removal. The raw and pretreated substrates were characterized and their biochemical methane production was measured. The results demonstrated the ability of some of the treatments to reduce d-limonene content up to 80%. A relatively high biomethane potential production of OPW (up to about 500 NmL CH₄ g^-1VS) was measured. The importance of the acclimation of inoculum and the risk connected to the accumulation of inhibiting substances in the reactor is discussed.

Selective arene production from transfer hydrogenolysis of benzyl phenyl ether promoted by a co-precipitated Pd/Fe3O4 catalyst

The catalytic transfer hydrogenolysis (CTH) of benzyl phenyl ether has been investigated using Pd/Fe₃O₄ as a heterogeneous catalyst and 2-propanol as a H-donor. After 90 minutes at 240 °C, the cleavage of the ester C–O bond occurs as the only reaction route, whereas hydrogenation of the aromatic ring was not observed.

Pilot study to evaluate the efficacy and safety of pneumatic trabeculoplasty in glaucoma and ocular hypertension

PURPOSE

Following laser-assisted in situ keratomileusis (LASIK), intraocular pressure (IOP) is measurably lower in a significant number of cases. It has been proposed that the decrease in IOP may be a real event. Prior trials have evaluated pneumatic trabeculoplasty (PNT) in combination with concomitant glaucoma medications. The aim of this study was to determine the efficacy and the safety of PNT alone to lower IOP in patients with primary open angle glaucoma (POAG) or ocular hypertension (OH).

METHODS AND RESULTS

A total of 37 subjects with POAG or OH were enrolled in a prospective, open-label, fellow-eye, multicenter trial to determine the IOP lowering effects of PNT. All subjects underwent ophthalmologic examinations and IOP measurements and were washed out from all glaucoma medications prior to the start of the study. The trial was intrapatient controlled for the first 30 days, with one eye receiving PNT at days 0 and 7 and the fellow eye serving as the control. The second eye was treated with PNT at day 30. The patients were followed for 120 days, with the first eye receiving an additional PNT treatment at days 90 and 97. Two analyses-an intent to treat analysis in which the last IOP measurement for patients dropped from the study was carried forward and an analysis including only those patients who completed the trial-were performed. Of the 37 patients enrolled, 27 (73%) completed the study. For the intent to treat analysis the baseline mean IOP was 24.7+/-1.9 mmHg for eye 1 and 23.6+/-2.3 mmHg for eye 2 and the difference was statistically significant (p<0.05). Using this analysis the differences between eye 1 mean IOP at days 1, 7, 14, and 60 and the baseline mean IOP were statistically significant (p<0.05). The differences between eye 2 mean IOP and the baseline mean IOP were statistically significant (p<0.05) at all time points except day 14 and day 30. The greater mean IOP reductions from the baseline mean IOP for eye 1 were at study day 1 (-16,1%), day 14 (-9%), and day 60 (-8.9%). For eye 2 they were at day 60 (-8.7%) and at day 120 (-9.1%). For the analysis that included only those subjects who completed the trial the decrease in eye 1 mean IOP from baseline was statistically significant (p<0.05) at all time points. The decrease in eye 2 mean IOP from baseline was statistically significant at all time points except day 30. Using this analysis the greater mean IOP reductions from the baseline mean IOP for eye 1 were at study day 1 (-19%), day 14 (-15.7%), day 37 (-16.3%), day 60 (-20.0%), day 90 (-18.1%), day 97 (-16.8%), and day 120 (-15.8%). For eye 2 greater mean IOP reductions from baseline mean IOP were seen on day 37 (-13.0%), day 60 (-16.7%), day 90 (-15.5%), day 97 (-14.5%), and day 120 (-7.2%). No statistically significant differences were found in mean IOP reduction between the two eyes treated. A total of 34 patients (92%) showed adverse effects: conjunctival hyperemia in 26 (70.3%) and conjunctival hemorrhage in 14 (37.8%).

CONCLUSIONS

This pilot study of PNT showed a potentially good IOP lowering effect on glaucoma and hypertensive patients. Additional studies would help to better define the types of patients who respond to PNT and to identify risk factors that may lead to treatment failure.

Ocular hypertension: 12 years' follow-up

A retrospective 12-year study on 35 patients having IOP values higher than 21 mmHg in repeated tonometric curves with no clinical glaucomatous-type signs was carried out with the aim of discovering the incidence of the eyes which evolved towards the glaucomatous disease, to evaluate the role of the preventive therapy and to observe how response to the ibopamine provocation test (which assesses outflow pathway compromission) was modified with time. The data obtained showed that, in 39.13% of the eyes, there was an evolution towards the disease. The ibopamine test was positive at time "0" (study begins) in 48.14% in the evolutive eyes and in 66.66% of the eyes which remained stable, while, at time "12" (study ends), almost all of the eyes (92-95%) had become positive. The role of precociously initiated ocular hypotensive therapy concurring with the test positivity is put in evidence.