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El presente trabajo fué iniciado originalmente como una curiosidad de laboratorio. La síntesis y propiedades investigadas posteriormente surgieron a medida que avanzaba el trabajo. Una búsqueda completaen el Chemical Abstracts desde el año 1907 hasta el presente, nos ha llevado a encontrar solo unas 8 citas bibliográficas, algunas de ellas no dirigidas específicamente a nuestro compuesto, sino en forma muygeneral al estudio de los tiazoles. (Véase revisión bibliográfica).

The characteristics of the background seismic noise recorded at the IberArray broadband seismic network have been analyzed using power spectral density estimates and their corresponding probability density functions (PDFs). The network is composed of 55 stations that have been deployed in southern Iberia and northern Morocco beginning in the summer of 2007. PDFs provide a useful tool for monitoring the network performance, allowing identification of stations with anomalously high noise levels. They can also be used to investigate the major sources of noise at different frequency bands and the seismic background noise variations related to time of day, season, weather, location, and type of installation. At high frequencies (> 1 Hz), the main contribution seems to arise from the cultural noise, and therefore significant variations are observed between noise levels at different stations based on proximity to populated areas. At microseismic frequencies (0.05-1 Hz), the noise level is more uniform among stations, although sites along the Gulf of Cádiz show a slightly increased level. At long periods, the vertical component noise level usually lies 15 dB above the new low-noise model and the horizontal components are much noisier, sometimes exceeding the new high-noise model for periods longer than 20 sec. Infragravity waves can be identified along the network for periods close to 100 sec, even for stations located inland. The distribution of the median noise levels across the IberArray network shows a clear correlation with major geological features, such as the Guadalquivir and Gharb sedimentary basins, where noise is high, and the Iberian Massif where the noise levels are lowest. Among the main temporal variations observed we can highlight the diurnal differences in the noise level, particularly significant for high frequencies, and the noise level variations correlated to the significant wave heights in the surrounding water bodies. [ABSTRACT FROM AUTHOR]

Some patients with autism and severe intellectual disability may experience uncontrolled aggression, causing serious injury or harm to others, and the therapeutic ineffectiveness of traditional pharmacological and behavioral treatment may aggravate symptoms. Deep brain stimulation (DBS) has been tested in patients with little evidence in children and adolescents. Therefore, we analyzed the efficacy and safety of DBS in refractory aggression in pediatric subjects with autism (ASD) and severe intelligence deficit (ID).Methods A meta-analytic review of Web of Science (WOS) and Scopus articles, following Prisma criteria. A total of 555 articles were identified, but after applying the inclusion criteria, only 18 were analyzed. The review of the registries and the extraction of information was performed by 2 independent groups, to reduce the evaluator's bias. For the description of the results, pediatric patients with ASD or ID present in each registry, with an application of specialized scales (Overt aggression scale, OAS, and THE modified version of the OAS, MOAS) pre and post-DBS, with a clinical follow-up of at least 12 months, were considered valid. Clinical improvement was calculated using tests of aggressiveness. In each registry with available data and then pooling the means of all patients in the OAS and MOAS, the effect size of DBS (overall and per study) was estimated. Finally, the adapted NOS scale was applied to rate the studies' quality and level of bias.Results In the studies analyzed, 65/100 were pediatric patients, with a mean age of 16.8 years. Most of the studies were conducted in South America and Europe. In all teams, aggressive behavior was intractable, but only 9 groups (53/65) applied specialized scales to measure aggressiveness, and of these, only 51 subjects had a follow-up of at least 12 months. Thus, in 48/51 a clinical improvement of patients was estimated (94.2%), with a considerable overall effect size (OAS: d = 4.32; MOAS: d = 1.46). However, adverse effects and complications were found in 13/65 subjects undergoing DBS. The brain target with the most evidence and the fewest side effects was the posteromedial hypothalamic nuclei (pHypN). Finally, applying the adapted NOS scale, quality, and bias, only 9 studies show the best indicators.Conclusion An optimal level of efficacy was found in only half of the publications. This is mainly due to design errors and irrelevant information in the reports. We believe that DBS in intractable aggressiveness in children and adolescents with ASD and severe ID can be safe and effective if working groups apply rigorous criteria for patient selection, interdisciplinary assessments, objective scales for aggressiveness, and known surgical targets., (© 2024. The Author(s).)

The rechargeable lithium air (oxygen) battery (Li-O 2 ) has very high energy density, comparable to that of fossil fuels (∼3600 W h kg -1 ). However, the parasitic reactions of the O 2 reduction products with solvent and electrolyte lead to capacity fading and poor cyclability. During the oxygen reduction reaction (ORR) in aprotic solvents, the superoxide radical anion (O 2 ˙ - ) is the main one-electron reaction product, which in the presence of Li + ions undergoes disproportionation to yield Li 2 O 2 and O 2 , a fraction of which results in singlet oxygen ( 1 O 2 ). The very reactive 1 O 2 is responsible for the spurious reactions that lead to high charging overpotential and short cycle life due to solvent and electrolyte degradation. Several techniques have been used for the detection and suppression of 1 O 2 inside a Li-O 2 battery under operation and to test the efficiency and electrochemical stability of different physical quenchers of 1 O 2 : azide anions, 1,4-diazabicyclo[2.2.2]octane (DABCO) and triphenylamine (TPA) in different solvents (dimethyl sulfoxide (DMSO), diglyme and tetraglyme). Operando detection of 1 O 2 inside the battery was accomplished by following dimethylanthracene fluorescence quenching using a bifurcated optical fiber in front-face mode through a quartz window in the battery. Differential oxygen-pressure measurements during charge-discharge cycles vs. charge during battery operation showed that the number of electrons per oxygen molecule was n > 2 in the absence of physical quenchers of 1 O 2 , due to spurious reactions, and n = 2 in the presence of physical quenchers of 1 O 2 , proving the suppression of spurious reactions. Battery cycling at a limited specific capacity of 500 mA h g C -1 for the MWCNT cathode and 250 mA g C -1 current density, in the absence and presence of a physical quencher or a physical quencher plus the redox mediator I 3 - /I - (with a lithiated Nafion® membrane), showed increasing cyclability according to coulombic efficiency and cell voltage data over 100 cycles. Operando Raman studies with a quartz window at the bottom of the battery allowed detection of Li 2 O 2 and excess I 3 - redox mediator during discharge and charge, respectively.

Excess iron is known to trigger adipose tissue dysfunction and insulin resistance. Circulating markers of iron status have been associated with obesity and adipose tissue in cross-sectional studies. We aimed to evaluate whether iron status is linked to changes in abdominal adipose tissue longitudinally. Subcutaneous abdominal tissue (SAT) and visceral adipose tissue (VAT) and its quotient (pSAT) were assessed using magnetic resonance imaging (MRI), at baseline and after one year of follow-up, in 131 (79 in follow-up) apparently healthy subjects, with and without obesity. Insulin sensitivity (euglycemic- hyperinsulinemic clamp) and markers of iron status were also evaluated. Baseline serum hepcidin ( p = 0.005 and p = 0.002) and ferritin ( p = 0.02 and p = 0.01)) were associated with an increase in VAT and SAT over one year in all subjects, while serum transferrin ( p = 0.01 and p = 0.03) and total iron-binding capacity ( p = 0.02 and p = 0.04) were negatively associated. These associations were mainly observed in women and in subjects without obesity, and were independent of insulin sensitivity. After controlling for age and sex, serum hepcidin was significantly associated with changes in subcutaneous abdominal tissue index (iSAT) (β = 0.406, p = 0.007) and visceral adipose tissue index (iVAT) (β = 0.306, p = 0.04), while changes in insulin sensitivity (β = 0.287, p = 0.03) and fasting triglycerides (β = -0.285, p = 0.03) were associated with changes in pSAT. These data indicated that serum hepcidin are associated with longitudinal changes in SAT and VAT, independently of insulin sensitivity. This would be the first prospective study evaluating the redistribution of fat according to iron status and chronic inflammation.