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Diet composition has a great impact on body composition. Several studies have suggested a beneficial effect of adding olive oil to a calorie-restricted diet as a weight loss strategy. However, there is no clear direction regarding the effect of olive oil on body fat distribution. This systematic review with meta -analysis aims to investigate the effect of olive oil consumption (for cooking or as a supplement) on body fat distribution in adults. The present study was conducted following the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions and was registered in the International Prospective Register of Systematic Reviews (PROSPERO CRD42021234652). All randomized clinical trials of parallel or crossover design found in PubMed ( via MEDLINE), EMBASE, Web of Science and Scopus databases that compared the effects of olive oil with other oils on body fat distribution in adults were included. 52 articles were included. The results indicate that the consumption of olive oil does not seem to alter the distribution of body fat, despite a small indication that supplementation in capsules can increase adipose mass (Mean Difference = 0.28 kg, 95% CI [-0.27, 0.83]; between-groups difference p = 0.59) and waist circumference (mean difference = 1.74 kg, 95% CI [0.86, 1.62]; between-groups difference p < 0.01) and decrease its auxiliary culinary use (mean difference = -0.32 kg, 95% CI [-0.90, 0.26]). Lean mass responds negatively to OO the higher the dose (slope = -0.61, 95% CI [-1.01, -0.21], p = 0.003) and time offered (slope = -0.8822, 95% CI [-1.44, -0.33], p = 0.002). In conclusion, this systematic review showed that OO ingestion in different delivery vehicles, dosages, and durations can interfere body composition. It is important to emphasize that some other aspects of the population and the intervention, that were not possible to be explored in the analysis, could confound the real effects of OO on body composition.

The kinetics of hydrolysis of dimethyl nitrophenyl phosphate (DMNP), a simulant of the nerve agent Soman, was studied and revealed transition metal salts as catalysts. The relative rates of DMNP hydrolysis by zirconium and hafnium chlorides are in accordance with their Lewis acidity. In situ conversion of zirconium chloride to zirconium oxy-hydroxide was identified as the key step. We propose a precursor-MOF activity relationship.

This manuscript describes the preparation of a new Ru(ii) nitrosylsulphito complex, trans-[Ru(NH 3 ) 4 (isn)(N(O)SO 3 )] + (complex 1), its spectroscopic and structural characterization, photochemistry, and thermal reactivity. Complex 1 was obtained by the reaction of sulfite ions (SO 3 2- ) with the nitrosyl complex trans-[Ru(NH 3 ) 4 (isn)(NO)] 3+ (complex 2) in aqueous solution resulting in the formation of the N-bonded nitrosylsulphito (N(O)SO 3 ) ligand. To the best of our knowledge, only four nitrosylsulphito metal complexes have been described so far (J. Chem. Soc., Dalton Trans., 1983, 2465-2472), and there is no information about the photochemistry of such complexes. Complex 1 was characterized by spectroscopic means (UV-Vis, EPR, FT-IR, 1 H- and 15 N-NMR), elemental analysis and single-crystal X-ray diffraction. The X-ray structure of the precursor complex 2 is also discussed in the manuscript and is used as a reference for comparisons with the structure of 1. Complex 1 is water-soluble and kinetically stable at pH 7.4, with a first-order rate constant of 3.1 × 10 -5 s -1 for isn labilization at 298 K (t 1/2 ∼ 373 min). Under acidic conditions (1.0 M trifluoroacetic acid), 1 is stoichiometrically converted into the precursor complex 2. The reaction of hydroxide ions (OH - ) with 1 and with 2 yields the Ru(ii) nitro complex trans-[Ru(NH 3 ) 4 (isn)(NO 2 )] + with second-order rate constants of 2.1 and 10.5 M -1 s -1 (at 288 K), respectively, showing the nucleophilic attack of OH - at the nitrosyl in 2 (Ru-NO) and at the nitrosylsulphito in 1 (Ru-N(O)SO 3 ). The pK a value of the -SO 3 moiety of the N(O)SO 3 ligand in 1 was determined to be 5.08 ± 0.06 (at 298 K). The unprecedented photochemistry of a nitrosylsulphito complex is investigated in detail with 1. The proposed mechanism is based on experimental (UV-Vis, EPR, NMR and Transient Absorption Laser Flash Photolysis) and theoretical data (DFT) and involves photorelease of the N(O)SO 3 - ligand followed by formation of nitric oxide (NO˙) and sulfite radicals (SO 3 ˙ - , sulfur trioxide anion radical).

We describe the kinetics of the formation and decay of a series of dithiocarbamates under physiological conditions. The goal is to provide a toolbox of compounds that release CS 2 by well-defined kinetics in such media. Carbon disulfide is a known environmental toxin, but there is fragmentary evidence suggesting that CS 2 may have bioregulatory and/or therapeutic roles in mammalian biology. Further investigation of such roles will require methodologies for controlled delivery of this bioactive small molecule to specific targets. Reported here are mechanistic and computational studies of CS 2 release from a series of dithiocarbamate anions (DTCs), where R 2 N represents several different secondary amido groups. The various DTCs under physiologically relevant conditions show a tremendous range of reactivities toward CS 2 dissociation with decay lifetimes ranging from ∼2 s for imidazolidyldithiocarbamate (ImDTC - ) to ∼300 s for diisopropyldithiocarbamate (DIDTC - ) to >24 h for pyrrolidinyldithiocarbamate (PDTC - ) in pH 7.4 phosphate buffer solution at 37 °C. Thus, by making the correct choice of these tools, one can adjust the flux of CS 2 in a biological experiment, while the least reactive DTCs could serve as controls for evaluating the potential effects of the dithiocarbamate functionality itself. Kinetics studies and density functional calculations are used to probe the mechanism of DTC - decay. In each case, the rate of CS 2 dissociation is acid dependent; however, the DFT studies point to a mechanistic pathway for ImDTC - that is different than those for DIDTC - . The role of general acid catalysis is also briefly probed.

The SERS enhancement factor (SERS-EF) is one of the most important parameters that characterizes the ability of a given substrate to enhance the Raman signal for SERS applications. The comparison of SERS intensities and SERS-EF values across different substrates is a common practice to unravel the performance of a given substrate. In this study, it is shown that such a comparison may lack significance if we compare substrates of very distinct nature and optical properties. It is specifically shown that the SERS-EF values for static substrates (e.g. immobilized metallic nanostructures) cannot be compared to those of dynamic ones (e.g. colloidal metal nanoparticle solutions), and that the optical properties for the latter show strong dependence on the metal-molecule interaction dynamics. The most representative experimental results concerning the dynamic substrates have been supported by generalized Mie theory simulations, which are tools used to describe the substrate complexity and the microscopic information not usually taken into account.

This work examines the effect of copper nanoparticles (Cu NPs) on the photocurrent efficiency of silicon photovoltaic (Si PV) devices. An optimized synthesis of stable Cu NPs is reported together with a procedure for their immobilization on the Si PV surface. A comprehensive analysis of the photocurrent and power dependence of the Cu NPs surface coverage and size is presented. A decrease in photoconversion was observed for wavelengths shorter than ~500 nm, due to the Cu interband absorption. In the low surface coverage limit, where the level of aggregation was found to be low, the surface plasmon resonance absorption dominates leading to a modest effect on the photocurrent response. As the number of aggregates increased with the surface coverage, the photocurrent efficiency also increased, and a maximum enhancement power conversion of 16% was found for a 54 ± 6 NPs per μm(2) PV cell. This enhancement was attributed to SPR light scattering and trapping into the Si PV device. Higher surface coverage yielded numerous aggregates which acted as a bulk coating and caused a decrease in both photocurrent and power measurements.