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The main purpose of this study was to compare the parameters of computed tomography (CT) and the corresponding patient doses undergoing chest CT scan examinations in different regions of Brazil, providing the current scenario of how these procedures are being carried out in the country as well as the patient dose distribution. Thirty institutions, across 17 states and the Federal District participated in the survey. The evaluation included 30 multislice CTs of seven different models, manufactured by General Electric healthcare (GE). For each institution, data from 10 adult chest CT examinations, performed without contrast, were collected remotely. The analysis of the results showed a significant difference of the CTDIvol values, ranging from 1.1 mGy to 46.6 mGy. In 7 institutions. The mean value of CTDIvol was higher than values found in the literature and the UK Reference Levels. It was also observed that, regardless of the region of the country, for the same CT model, different scanning parameters were used, which resulted in CTDIvol up to five times higher among these institutions. Repetitions of CT acquisitions and scouts with radiation field dimensions larger than the region of interest were found in 25% of chest examinations, resulting in higher absorbed doses. The results of this work show a mapping of the chest CT procedures, which enable to establish strategic plans for the country. In addition, each institution will be able to implement an appropriate optimization program and establish institutional reference levels.

Background: This work presents the preparation and characterization of the polymeric nanocomposites based on methyl methacrylate (MMA), ethyl acrylate (EA), and natural and modified clays. The clays used to prepare the composite were natural green bentonite (GBC-N) and organophilic clays modified with ammonium quaternary salts: Praepagen (GCB-P), Dodigen (GCB-D) and Praepagen/Dodigen mixture 1:1 in weight (GCB-P/D). Objective: The experimental studies focused on the evaluation of the effect of clays (in nature and chemically modified) on the final quality of the polymeric nanocomposites containing around 3 wt%. of clay nanocharges in association with MMA to produce poly(methyl methacrylate)/clays, and MMA/EA to form poly(methyl methacrylate-co-ethyl acrylate)/clays. Methods: The poly(methyl methacrylate)/clay and poly(methyl methacrylate-co-ethyl acrylate)/- clay materials were synthesized through mass-suspension polymerization process. The natural and modified green bentonite clays were characterized by X-ray powder diffraction (XRD), infrared spectroscopy (IR), Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) analyses to understand its effect on the basal spacing, d001 (compared to the pure clay), as a result of cation exchange step, which also improved the thermal efficiency of the final nanocomposites. Results: The proper incorporation of MMA and MMA/EA monomers between the layers of natural and modified clays occurred through in situ mass-suspension polymerization, leading to a successful exfoliation of clay layers during the growth of the polymer chains. Conclusion: The IR, SEM, TGA and DSC analyses confirmed the improvement in the thermal property of the composites compared to polymers formed in the absence of clays. The experimental results are very promising, indicating that the experimental protocol based on the in situ formation of polymer nanocomposites by using sequential mass-suspension polymerization consisting of an interesting tool.

The aim of this multi-centre study was to evaluate the irradiation parameters and the radiation dose of abdomen CT exams without contrast, performed in adults In Brazil, in order to provide an overview of the CT installed base in the country and contribute for the establishment of optimization programs. Equipment of seven different models, with 16 and 64 channels, installed in 17 Brazilian states, plus the Federal District, were analyzed. The results show that the mean CTDIvol ranged from 6.60 mGy to 34.64 mGy. The results also showed that different irradiation parameters are used in equipment of the same model, resulting, in some cases, in three times higher CTDIvol values. These characteristics are not restricted to a given region of the country but distributed throughout the national territory. Repetitions of acquisitions and topograms with scan length larger than the region of interest were found in 13.5% of abdomen examinations, resulting in considerably higher absorbed doses than expected. This survey of the abdomen tomography exams, performed in about 74% of the Brazilian states, showed that in many clinics the procedures are not optimized. This study can be used for the planning of dose optimization programs and will contribute to the establishment of local diagnostic reference levels (DRL) for CT.

Background: While osimertinib, a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) is the standard treatment in patients with advanced non-small-cell lung cancer (NSCLC) with sensitising EGFR and acquired T790M mutations, progression inevitably occurs. The angiogenic pathway is implicated in EGFR TKI resistance. Patients and methods: BOOSTER is an open-label randomised phase II trial investigating the efficacy and safety of combined osimertinib 80 mg daily and bevacizumab 15 mg/kg every 3 weeks, versus osimertinib alone, in patients with EGFR-mutant advanced NSCLC and acquired T790M mutations after failure on previous EGFR TKI therapy. Primary endpoint was investigator-assessed progression-free survival (PFS). Secondary endpoints were overall survival (OS), objective response rate (ORR) and adverse events (AEs). Results: Between May 2017 and February 2019, 155 patients were randomised (combination: 78; osimertinib: 77). At data cut-off of 22 February 2021, median follow-up was 33.8 months [interquartile range (IQR): 26.5-37.6 months] and 129 (83.2%) PFS events were reported in the intention-to-treat population. There was no difference in median PFS between the combination [15.4 months; 95% confidence interval (CI) 9.2-18.0 months] and osimertinib arm (12.3 months; 95% CI 6.2-17.2 months; stratified log-rank P = 0.83), [hazard ratio (HR) = 0.96; 95% CI 0.68-1.37]. Median OS was 24.0 months (95% CI 17.8- 32.1 months) in the combination arm and 24.3 months (95% CI 16.9-37.0 months) in the osimertinib arm (stratified log-rank P = 0.91), (HR = 1.03; 95% CI 0.67-1.56). Exploratory analysis revealed a significant interaction of smoking history with treatment for PFS (adjusted P = 0.0052) with a HR of 0.52 (95% CI 0.30-0.90) for smokers, and 1.47 (95% CI 0.92-2.33) for never smokers. ORR was 55% in both arms and the median time to treatment failure was significantly shorter in the combination than in the osimertinib arm, 8.2 months versus 10.8 months, respectively (P = 0.0074). Safety of osimertinib and bevacizumab was consistent with previous reports with grade >= 3 treatment-related AEs (TRAEs) reported in 47% and 18% of patients on combination and osimertinib alone, respectively. Conclusions: No difference in PFS was observed between osimertinib plus bevacizumab and osimertinib alone. Grade >= 3 TRAEs were more common in patients on combination.

To assess moral distress (MD) among Spanish critical care healthcare professionals (HCPs).Cross-sectional, prospective study.ICUs in Spain.HCPs currently working in Spanish ICUs.A 55-item questionnaire was electronically distributed.The questionnaire included work-related and socio-demographic characteristics, the Spanish version of the Measure of Moral Distress for Health Care Professionals (MMD-HP-SPA), and the Hospital Ethical Climate Survey (HECS).In total, 1065 intensive care providers completed the questionnaire. Three out of four validity hypotheses were supported. MD was significantly higher for physicians (80, IQR 40-135) than for nurses (61, IQR 35-133, p=0.026). MD was significantly higher for those clinicians considering leaving their position (78, IQR 46-163 vs. 61, IQR 32-117; p0.001). The MMD-HP-SPA was inversely correlated with the HECS (r=-0.277, p0.001). An exploratory factor analysis revealed a four-factor structure, evidencing the patient, team, and system levels of MD.In the study sample, Spanish intensivists report higher MD than nurses. Strategies to improve ICU ethical climate and to correct other related factors in order to mitigate MD at a patient, team, and system level should be implemented. Both groups of HCPs manifest a relevant intention to leave their position due to MD. Further studies are needed to determine the extent to which MD influences their desire to leave the job.

© The Author(s) 2020. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Cre-ative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not per-mitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/., Cutaneous secretions of amphibians have bioactive compounds, such as peptides, with potential for biotechnological applications. Therefore, this study aimed to determine the primary structure and investigate peptides obtained from the cutaneous secretions of the amphibian, Leptodactylus vastus, as a source of bioactive molecules. The peptides obtained possessed the amino acid sequences, GVVDILKGAAKDLAGH and GVVDILKGAAKDLAGHLASKV, with monoisotopic masses of [M + H]± = 1563.8 Da and [M + H]± = 2062.4 Da, respectively. The molecules were characterized as peptides of the class of ocellatins and were named as Ocellatin-K1(1-16) and Ocellatin-K1(1-21). Functional analysis revealed that Ocellatin-K1(1-16) and Ocellatin-K1(1-21) showed weak antibacterial activity. However, treatment of mice with these ocellatins reduced the nitrite and malondialdehyde content. Moreover, superoxide dismutase enzymatic activity and glutathione concentration were increased in the hippocampus of mice. In addition, Ocellatin-K1(1-16) and Ocellatin-K1(1-21) were effective in impairing lipopolysaccharide (LPS)-induced reactive oxygen species (ROS) formation and NF-kB activation in living microglia. We incubated hippocampal neurons with microglial conditioned media treated with LPS and LPS in the presence of Ocellatin-K1(1-16) and Ocellatin-K1(1-21) and observed that both peptides reduced the oxidative stress in hippocampal neurons. Furthermore, these ocellatins demonstrated low cytotoxicity towards erythrocytes. These functional properties suggest possible to neuromodulatory therapeutic applications., Alexandra Plácido is a recipient of a post-doctoral grant from the project FCT (PTDC/BII-BIO/31158/2017). Renato Socodato and Camila Cabral Portugal hold postdoctoral fellowships from FCT (Refs: SFRH/BPD/91833/2012 and FRH/BPD/91962/2012, respectively). This work was funded through project UID/QUI/50006/2013-POCI/01/0145/FEDER/007265 (LAQV/REQUIMTE) with financial support from FCT/MEC through national funds and co-financed by FEDER, under the Partnership Agreement PT 2020

Asymptomatic patients may exhibit symptoms during objective exercise testing, but whether symptoms are due to the obstructively of the valve (typified by the mean gradient) or underlying ventricular function remains unknown. While the mean gradient is an easy parameter to measure no consensus about the measurement of contractile reserve exists. Longitudinal abnormalities may occur in the presence of a normal ejection fraction and the augmentation of these parameters is poorly described. To obtain an objective regarding patients exercise ability is best determined using cardiopulmonary exercise testing. We therefore examined echocardiographic predictors of exercise ability during cardiopulmonary exercise testing.24 asymptomatic patients with moderate to severe or severe aortic stenosis and preserved ejection fraction underwent stress echocardiography with simultaneous cardiopulmonary exercise testing. The primary assessment of exercise ability was the VO2peak and OUES. Echocardiography was measured at rest and during maximal exercise (defined as RER > 1)OUES and VO2peak showed a poor relationship with conventional parameters of severity including peak and mean gradients, AVA and dimensionless index, resting systolic function (by EF and TDI). During exercise systolic augmentation had a good relationship with exercise ability but the exercise mean gradient and exercise LVEF did not.Longitudinal systolic function and particularly systolic augmentation is the strongest predictor of exercise ability when compared to conventional measures of severity.VO2peakOUESS' exerciseRho=0.69 (p=0.001)R= 0.71 (p=0.001)S' restRho=0.52 (p=0.01)R= 0.44 (p=ns)Rest AV max VRho= 0.09 (p=ns)R= -0.08 (p=ns)Rest AV mean PGRho= 0.34 (p=ns)R=-0.10 (p=ns)Exercise AV max VRho=0.43 (p=0.05)R=0.23 (p=ns)Exercise AVmean PGRho= 0.51 (p=0.001)R=0.26 (p=ns)Rest AVARho=0.40 (p=ns)Rho=0.46 (p=0.04)Dimensionless indexRho=0.15 (p=ns)R=0.13 (p=ns)LVEF restRho=-0.18 (p=ns)R=-0.32 (p=ns)LVEF exerciseRho=0.18 (p=ns)R=0.17 (p=ns)S' - systolic velocity; V - velocity; AV - aortic valve; AVA- aortic valve area; LVEF - left ventricular ejection fraction.

The structure of cytochrome c (GSU3274) designated as PccH from Geobacter sulfurreducens was determined at a resolution of 2.0 Å. PccH is a small (15 kDa) cytochrome containing one c-type heme, found to be essential for the growth of G. sulfurreducens with respect to accepting electrons from graphite electrodes poised at -300 mV versus standard hydrogen electrode. with fumarate as the terminal electron acceptor. The structure of PccH is unique among the monoheme cytochromes described to date. The structural fold of PccH can be described as forming two lobes with the heme sandwiched in a cleft between the two lobes. In addition, PccH has a low reduction potential of -24 mV at pH 7, which is unusual for monoheme cytochromes. Based on difference in structure, together with sequence phylogenetic analysis, we propose that PccH can be regarded as a first characterized example of a new subclass of class I monoheme cytochromes. The low reduction potential of PccH may enable the protein to be redox active at the typically negative potential ranges encountered by G. sulfurreducens. Because PccH is predicted to be located in the periplasm of this bacterium, it could not be involved in the first step of accepting electrons from the electrode but is very likely involved in the downstream electron transport events in the periplasm.

Schistosomiasis, caused by helminth flatworms of the genus Schistosoma, is an infectious disease mainly associated with poverty that affects millions of people worldwide. Since treatment for this disease relies only on the use of praziquantel, there is an urgent need to identify new antischistosomal drugs. Piplartine is an amide alkaloid found in several Piper species (Piperaceae) that exhibits antischistosomal properties. The aim of this study was to evaluate the structure&ndash, function relationship between piplartine and its five synthetic analogues (19A, 1G, 1M, 14B and 6B) against Schistosoma mansoni adult worms, as well as its cytotoxicity to mammalian cells using murine fibroblast (NIH-3T3) and BALB/cN macrophage (J774A.1) cell lines. In addition, density functional theory calculations and in silico analysis were used to predict physicochemical and toxicity parameters. Bioassays revealed that piplartine is active against S. mansoni at low concentrations (5&ndash, 10 &micro, M), but its analogues did not. In contrast, based on 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry assays, piplartine exhibited toxicity in mammalian cells at 785 &micro, M, while its analogues 19A and 6B did not reduce cell viability at the same concentrations. This study demonstrated that piplartine analogues showed less activity against S. mansoni but presented lower toxicity than piplartine.

Schistosomiasis is a neglected tropical disease caused by blood flukes of the genus Schistosoma. This disease control has been widely made by praziquantel-reference drug, but resistance to this drug has already been found. There has been the finding of an imidazole alkaloid in jaborandi leaves-epiisopiloturine, which has known activity against adult, young and egg forms of Schistosoma mansoni. This alkaloid is an apolar molecule with difficult solubility; therefore, the liposomal structure of epiisopiloturine was proposed. Liposomes are carrying structures of drugs that may enhance solubility of compounds such as epiisopiloturine. In this work, we report in vitro epiisopiloturine-loaded liposomes effect formed by different concentrations of lipids 9:1 (weight ratio) dipalmitoylphosphatidylcholine:cholesterol and 8:2 (weight ratio) dipalmitoylphosphatidylcholine:cholesterol. Results have showed that epiisopiloturine extraction and isolation have been successful through high-performance liquid chromatography-HPLC and its purity confirmed through mass spectrometry has showed 287 Da molecular mass. Formulations from 9:1 DPPC:cholesterol and 8:2 DPPC:cholesterol with loaded EPI (300 microg/ml) have killed parasites at 100% after incubation 96 h and 120 h, respectively. Confocal microscopy employed to observe morphological alterations in the tegument of adult form of Schistosoma mansoni. Details from interaction, between epiisopiloturine and liposome, have been achieved by semi-empirical AM1 calculations, which have showed that epiisopiloturine inside is more stable than the outside form, at least 10 kcal. This is first time that schistosomicidal activity has been reported for epiisopiloturine-loaded into liposome.

Aminopropylated functionalised hexagonal mesoporous silicas (HMS) and SBA-15 materials with different amino-loadings (5–30 wt.% NH2) were synthesized, characterised and their catalytic activities were subsequently investigated in the microwave-assisted Knoevenagel condensation of cyclohexanone and ethyl cyanoacetate as well as in the Michael reaction between 2-cyclohexen-1-one and nitromethane. The effects of the quantity of the catalyst in the reaction as well as a variety of microwave parameters including the power, temperature and time of microwave irradiation were optimised. High activities and selectivities to the condensation product could be achieved at short times of microwave irradiation for both base-catalysed processes. The low loaded HMS-5%NH2 and higher loaded SBA-15-20%NH2 were found to give the best activities in the reactions. This observation seems to be related to the significant deterioration observed in textural properties of HMS materials at amino-loadings larger than 10%.

Schistosomiasis is a world health problem, and praziquantel is the only drug currently used for the treatment. There is some evidence that extensive monotherapy of praziquantel may be leading to drug resistance in the parasite. In order to find alternative treatments, the effects of the combination of epiisopiloturine (EPI), piplartine (PPT) and praziquantel (PZQ) were evaluated. Similarity analysis of these compounds was performed using optimized molecular structures to compare the shape and the charge modeling of combinations between PZQ and EPI or PPT. Supported by this data, in vitro association of PZQ-PPT, PZQ-EPI, and EPI-PPT was carried out, and the activity of these combinations against Schistosoma mansoni was assessed. The results showed synergistic activity with a combination index (CI) of 0.42 for the treatment with PZQ-PPT. Both PZQ-EPI and EPI-PPT combinations also showed synergistic effects, with CI values of 0.86 and 0.61, respectively. Surface alterations in the tegument of adult schistosomes after the treatments were observed using laser confocal microscopy and scanning electron microscopy. Additionally, the association of EPI-PPT decreased the cytotoxicity when compared with both isolated compounds in three different lines of mammalian cells. Thus, synergistic combinations of PZQ-PPT, PZQ-EPI, and EPI-PPT create the possibility of reduced doses to be used against Schistosoma mansoni.

Biomass can efficiently replace petroleum in the production of fuels for the transportation sector. One effective strategy for the processing of complex biomass feedstocks involves previous conversion into simpler compounds (platform molecules) which are more easily transformed in subsequent upgrading reactions. Lactic acid and levulinic acid are two of these relevant biomass derivatives which can easily be derived from biomass sources by means of microbial and/or chemical routes. The present paper intends to cover the most relevant catalytic strategies designed today for the conversion of these molecules into advanced biofuels (e.g. higher alcohols, liquid hydrocarbon fuels) which are fully compatible with the existing hydrocarbons-based transportation infrastructure. The routes described herein involve: (i) deoxygenation reactions which are required for controlling reactivity and for increasing energy density of highly functionalized lactic and levulinic acid combined with (ii) C C coupling reactions for increasing molecular weight of less-oxygenated reactive intermediates.

Low-load iron oxide nanoparticles on Al-SBA-15 prepared using a novel dry milling approach exhibited excelling activities in the microwave-assisted akylation of toluene with benzyl chloride (Lewis acids promoted reaction) and benzyl alcohol (Bronsted acids promoted reaction) as compared to the parent Al-SBA-15 and similar iron oxide nanoparticles supported on Al-MCM-41 materials. Materials prepared using the milling protocol possessed remarkably low iron loadings (

Tars and alkali ashes from biomass gasification processes currently constitute one of the major problems in biomass valorisation, generating clogging of filters and issues related with the purity of syngas production. To date, these waste residues find no useful applications and they are generally disposed upon generation in the gasification process. A detailed analysis of these residues pointed out the presence of high quantities of Ca (>30 wt%). TG experiments indicated that a treatment under air at moderate temperatures (400–800°C) decomposed the majority of carbon species, while XRD indicated the presence of a crystalline CaO phase. CaO enriched valorized materials turned out to be good heterogeneous catalysts for biodiesel production from vegetable oils, providing moderate to good activities (50%–70% after 12 h) to fatty acid methyl esters in the transesterification of sunflower oil with methanol.

Schistosomiasis, caused by blood flukes of the genus Schistosoma, still imposes a considerable public health burden on large parts of the world. The control of this disease depends almost exclusively on the drug praziquantel, and there are no alternative drugs in sight. Natural compounds have recently attracted significant attention due to their relevance to parasitic infection and potential development into new therapeutic agents. Epiisopiloturine is an imidazole alkaloid isolated from the leaves of Pilocarpus microphyllus (Rutaceae), a native plant from Brazil. Here, we report the in vitro effect of this drug on the survival time of Schistosoma mansoni of different ages, such as 3 h old and 1, 3, 5, and 7 days old schistosomula, 49-day-old adults, and on egg output by adult worms. Epiisopiloturine at a concentration of 300 μg/mL caused the death of all schistosomula within 120 h. Extensive tegumental alterations and death were observed when adult schistosomes had been exposed to 150 μg/mL of the epiisopiloturine. At the highest sub-lethal dose of alkaloid (100 μg/mL), a 100% reduction in egg laying of paired adult worms was observed. Additionally, epiisopiloturine showed selective antischistosomal activity and exhibited no cytotoxicity to mammalian cells. This report provides the first evidence that epiisopiloturine is able to kill S. mansoni of different ages and inhibit worm egg laying.

A detailed investigation on the microwave-assisted preparation of iron oxide nanoparticles on mesoporous Si-SBA-15 support is described, employing a dedicated single-mode microwave reactor with internal reaction temperature control. Using iron(II) chloride as iron precursor and ethanol as solvent, extensive optimization studies demonstrate that after 3–5 min at 150–200 °C well-defined 3–5 nm iron oxide nanoparticles (Fe2O3, hematite phase) are obtained. In contrast to the chosen reaction temperature, reaction time and stirring efficiency are of critical importance in the preparation of these supported nanoparticles. Extended reaction times (>10 min) lead to a significant proportion of larger aggregates while inefficient stirring also produces low quality nanoparticles as a result of poor dispersion and delivery of the iron precursor to the mesoporous support. Carefully executed control studies between microwave and conventionally heated experiments applying otherwise identical reaction conditions demonstrate that the quality of the obtained supported iron oxide nanoparticles is largely independent on the heating mode, as long as a the exact same temperature profile can be maintained.

The liquid phase catalytic hydrogenation of Acrolein (A) and Methyl-vinylketone (MVK) were studied over a series of new nickel catalysts supported on AlPO4, and AlPO4-Al2O3 and AlPO4-SiO2 systems, in methanol as solvent, at initial hydrogen pressure of 4.1 bar and temperatures between 298-323 K. The hydrogenation of the C-C double bond, yielding propanal or butanone were obtained in a first step at a yield of 100% because the reduction of butanone was not possible and, in the acrolein hydrogenation a kinetically consecutive process, acrolein propanal 1-propanol, was obtained and 1-propanol appeared just after acrolein was finished. The C-C double bond of acrolein was hydrogenated more slowly than it was in methyl-vinyl-ketone. This result is probably due to an electronic effect of substitution from the methyl group. Moreover, the catalytic activity varies markedly with the support and was found to diminish as the nickel content decreased. The order of decreasing activity for the C-C double bond: Ni/AlPO4-SiO2 > Ni/AlPO4 > Ni/AlPO4-Al2O3 is valid for the hydrogenation of both substrates and it is associated with an effect of metal-support interaction.

Styrene (S) and its α-methyl derivative (MS) were competitively hydrogenated over a series of nickel catalysts supported on the AlPO4, AlPO4-Al2O3 and AlPO4-SiO2 systems, using methanol as solvent, under initial hydrogen pressure in the range 0.4-0.6 MPa and temperatures between 288 and 323 K, obtaining the relative reactivities RMS,S and the relative adsorption constants KMS,S. The RMS,S and KMS,S values were less than unity in the range 0.04-0.08 indicating that S was adsorbed more strongly and less hindered on these catalysts than MS. With respect to the influence of temperature and pressure on competitive hydrogenation, the relative reactivity RMS,S was found to be independent of the initial hydrogen pressure while the changes of RMS,S with temperature followed and Arrhenius-type law below a temperature limit. This limit, as well as the slopes and intercepts of the representation log RMS,S vs. T−1, depended on the supports.

Gas-phase Beckmann rearrangement of cyclododecanone oxime (Cdox) to ω-laurolactam is reported for the first time on Al,B-MCM-41 catalysts. The Cdox conversion was studied by using a temperature programmed reaction experiment in the 325–450 °C temperature range employing 0.15 M Cdox in toluene/acetone solution. The oxime conversion increased gradually with reaction temperature from ca. 90% at 325 °C to ca. 95% at 450 °C, whereas the yield of the desired product ω-laurolactam decreased. The optimal reaction temperature was 375 °C, which balanced the conversion of Cdox, selectivity to ω-laurolactam and catalyst lifetime. In parallel, liquid-phase experiments were carried out under conventional heating. Weak and medium strength acid sites, higher strong acid B/L ratios and adequate pore diameter of untreated Al,B-MCM-41 materials favored an optimal performance for the gas-phase Beckmann rearrangement of Cdox, clearly improving the conversion, selectivity to ω-laurolactam and catalyst lifetime in gas-phase with respect to the conventional liquid-phase reactions.

Zr-SBA-15 materials were synthesized and the activity of the catalysts was investigated in the alkylation of aromatics with benzyl chloride. While Zr-SBA-15 materials needed more than 12 h of reaction to achieve quantitative conversion, an unusually high catalytic activity was observed for reused materials that provided quantitative conversions of starting material in less than 1 h. This dramatic increase in activity observed for reused and/or treated Zr-SBA-15 in the alkylation of aromatics with benzyl chloride points to the formation of novel highly acidic Lewis ClxZr–O–Si species on the catalyst surface.

The facile preparation of a range of supported nanoparticles on porous materials was successfully accomplished through the use of a range of environmentally friendly protocols including a modified impregnation/reduction methodology, ultrasounds and microwave irradiation. Materials were characterised by transmission electron microscopy (TEM) and XPS. Different morphologies including conventional nanospheres, nanoflower aggregates, nanorod-like structures and nanocubes were achieved under different conditions. The reported supported nanoparticles are envisaged to have interesting applications in various areas including catalysis, optics and sensors.

The homogeneous ruthenium complex [RuIICl2(bpea)(PPh3)], where bpea = N,N-bis-(2-pyridylmethyl)ethylamine, has been immobilised on an amorphous AlPO4 support through phosphamide bonds that are comparatively more stable than organosilane bonds. The catalyst was characterised by means of UV–vis and DRIFT and its activity was compared to that of the homogeneous complex in the liquid-phase hydrogenation of a range of alkenes. The heterogenized catalyst exhibited very good activities and excellent reusabilities (up to 25 runs) in the hydrogenation reaction.

The preparation of modified SBA-1 materials with alkaline ions was carried out at incipient wetness. The incorporation of such alkaline ions rendered basic SBA-1 materials. The material Na-SBA-1, obtained after the incorporation of 3 wt% Na, exhibited a very similar structure and a 25% reduction in surface area compared to that of the parent SBA-1. The Na-SBA-1 was also found to be the most active material in the Knoevenagel condensation of benzaldehyde and benzylacetone with ethyl cyanoacetate, both under conventional heating and microwave irradiation conditions. Nevertheless, the microwave assisted protocol was proved to enhance the reaction yields, reducing both the time of reaction and the energy consumption.

Metal nanoparticles have attracted much attention over the last decade owing to their unique properties as compared to their bulk metal equivalents, including a large surface-to-volume ratio and tunable shapes. To control the properties of nanoparticles with particular respect to shape, size and dispersity is imperative, as these will determine the activity in the desired application. Supported metal nanoparticles are widely employed in catalysis. Recent advances in controlling the shape and size of nanoparticles have opened the possibility to optimise the particle geometry for enhanced catalytic activity, providing the optimum size and surface properties for specific applications. This Review describes the state of the art with respect to the preparation and use of supported metal nanoparticles in catalysis. The main groups of such nanoparticles (noble and transition metal nanoparticles) are highlighted and future prospects are discussed.

Ga-, Al- and AlGa-SBA-15 mesoporous materials were synthesized via a direct sol–gel hydrothermal protocol. The SBA-15 materials were characterized using X-ray fluorescence (XRF), X-ray diffraction (XRD), N2 physisorption, transmission electron microscopy (TEM) and pyridine and 2,6-dimethylpyridine titration. The activity of the Ga- and AlGa-SBA-15 was investigated in the Friedel–Crafts alkylation of toluene with benzyl chloride (promoted by Lewis acidity) and benzyl alcohol (promoted by Bronsted acidity). Quantitative conversion of the starting material was found for all Ga- and AlGa-SBA-15 after a few hours of reaction at 110 °C in the alkylation of toluene with benzyl chloride. The mesoporous acidic materials provided very poor activities in the alkylation of toluene with benzyl alcohol, with the exception of the Al-SBA-15. The activities of the Ga- and AlGa-SBA-15 were correlated to the higher proportion of Lewis compared to Bronsted acid sites. The solid acids were also highly reusable preserving almost their initial catalytic activity after five reuses.

Mesoporous organically modified Ti-MCM-41 materials were synthesized employing different Ti precursors. Materials were found to possess improved properties in terms of stability, hydrophobicity and activity compared to the parent Ti-MCM-41, preserving their mesoporous structural order. The organically modified mesoporous materials were found to be very active and selective in the oxidation of various substrates including alcohols and alkenes under microwave irradiation using hydrogen peroxide. The materials were also highly stable and reusable up to four times preserving over 90% of their initial activity. The high activity and stability of the solids can be attributed to the higher Ti loading compared to the parent material as well as to an increase in hydrophobicity due to the organic functionalisation.