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Let $X$ be a regular tame stack. If $X$ is locally of finite type over a field, we prove that the essential dimension of $X$ is equal to its generic essential dimension, this generalizes a previous result of P. Brosnan, Z. Reichstein and the second author. Now suppose that $X$ is locally of finite type over a $1$-dimensional noetherian local domain $R$ with fraction field $K$ and residue field $k$. We prove that $\operatorname{ed}_{k}X_{k} \le \operatorname{ed}_{K}X_{K}$ if $X\to \operatorname{Spec} R$ is smooth and $\operatorname{ed}_{k}X_{k} \le \operatorname{ed}_{K}X_{K}+1$ in general.

There are sex differences in vulnerability to Coronavirus disease 2019 (COVID-19). The coronavirus S protein mediates viral entry into target cells employing the host cellular serine protease TMPRSS2 for S-protein priming. The TMPRSS2 gene expression is responsive to androgen stimulation and it could partially explain sex differences. We hypothesized that men chronically exposed to 5-alpha reductase inhibitors (5ARIs) for benign prostate hyperplasia (BPH) have a lower risk of hospitalization for COVID-19.This is a population-based case-control study on consecutive patients positive for SARS-CoV-2 virus who required hospitalization for COVID-19 (cases), age-matched to beneficiaries of the Lombardy Regional Health Service (controls). Data were collected by two high-volume COVID-19 regional centers of Lombardy (Italy). The primary outcome was to compare the prevalence of patients chronically exposed to 5ARIs, who required hospitalization for COVID-19, with the one of controls.Overall, 943 males were enrolled; 45 (4.77%) were exposed to 5ARI. COVID-19 patients aged55 years under 5ARI treatment were significantly less than expected on the basis of the prevalence of 5ARI treatment among age-matched controls (5.57 vs. 8.14%; P=0.0083, 95% CI: 0.75-3.97%). This disproportion was higher for men aged65 (7.14 vs. 12.31%; P=0.0001, 95% CI: 2.83-6.97%). Eighteen 5ARIs-patients died; the mean age of men who died was higher than those who did not: 75.98±9.29 vs. 64.78±13.57 (P0.001). Cox-regression and multivariable models did not show correlation between 5ARIs exposure and protection against intensive care unit admission/death.Men exposed to 5ARIs might be less vulnerable to severe COVID-19, supporting its use in disease prophylaxis.

Il progetto "Abitare il Museo" opera tre scelte: 1. Qualificazione del MEIS come struttura di ospitalità rendendo possibile l'esperienza attiva delle consuetudini della tradizione ebraica, del suo radicamento in Italia, con la realizzazione di un ostello per lo studio. 2. Conservazione integrale del complesso monumentale storico in cui ha sede,. 3. Innovazione/integrazione attraverso innesti a forte connotazione estetica ispirati all'alfabeto ebraico, ai suoi rapporti culturali e significati simbolici.

The aim of this study was to analyze the responses of women to the repeated bout effect (RBE) and to a short eccentric training program. Twenty-four young females were randomly assigned to a training group (TG, n = 14) or a control group (CG, n = 10). They performed two identical acute eccentric bouts (120 repetitions at 70% of 1RM) in a leg-press device in an 8 weeks interval. TG followed a 4-week-eccentric-training program between the bouts. Maximal isometric contraction, range of motion, peak power and quadriceps muscle soreness were compared between and within groups before and after the two acute eccentric bouts. TG and CG presented significant losses of isometric strength and peak power, and an increment in soreness after the first bout. Isometric strength and peak power were recovered faster in CG after the second bout (p0.05) compared with TG, which showed a similar recovery of these parameters after the second bout compared with the first one. A decrease in soreness and a faster recovery of range of motion were found in TG (p0.05) following the second bout compared with the first one, but not in CG. Data indicate that a 4-week eccentric training program may prevent the RBE over those adaptations related with muscle damage (e.g. strength loss), but it may increase RBE impact on inflammatory processes (e.g. soreness). Key pointsAn acute bout of eccentric exercise induces losses of strength, peak power and range of motion, and increases muscle soreness in young active women.When the acute eccentric bout is repeated by young women, the losses of strength and power are smaller, indicating less muscle damage. However, muscle pain and range of motion do not present any difference with the results obtained after the first bout, which would indicate that the repeated bout effect does not affect inflammatory response after acute eccentric exercise.Four weeks of eccentric training is enough to increase maximal isometric strength, but not dynamic strength (1RM) or peak power. Furthermore, this training seems to prevent those adaptations provided by the repeated bout effect related with muscle damage. On the other hand, the eccentric training seems to be a positive tool to decrease muscle soreness, and thus the inflammatory response, associated to a repeated acute eccentric bout.

The development of sustainable synthetic routes to access valuable oxazolidinones via CO2 fixation is an active research area, and the aziridine/carbon dioxide coupling has aroused a considerable interest. This reaction is featured by a high activation barrier, so to require a catalytic system, and may present some other critical issues. Here, we describe the straightforward gram-scale synthesis of a series of 5-​aryl-​2-oxazolidinones at ambient temperature and atmospheric CO2 pressure, in the absence of any catalyst/co-catalyst. The key to this innovative procedure consists in the direct transfer of the pre-formed amine/CO2 adduct (carbamate) to common aziridine precursors (dimethylsulfonium salts), replacing the classical sequential addition of amine (intermediate isolation of aziridine) and then CO2. The reaction mechanism has been investigated by NMR studies and DFT calculations applied to model cases.

Nitriles (N≡CR) are ubiquitous in coordination chemistry, yet literature studies on metal–nitrile bonding based on a multi-technique approach are rare. We selected an easily-available di-organoiron framework, containing both π-acceptor (CO, aminocarbyne) and donor (Cp = η5−C5H5) ligands, as a suitable system to provide a comprehensive description of the iron–nitrile bond. Thus, the new nitrile (2–12)CF3SO3 and the related imine/amine complexes (8–9)CF3SO3 were synthesized in 58–83% yields from the respective tris-carbonyl precursors (1a–d)CF3SO3, using the TMNO strategy (TMNO = trimethylamine-N-oxide). The products were fully characterized by elemental analysis, IR (solution and solid state) and multinuclear NMR spectroscopy. In addition, the structures of (2)CF3SO3, (3)CF3SO3, (5)CF3SO3 and (11)CF3SO3 were ascertained by single crystal X-ray diffraction. Salient spectroscopic data of the nitrile complexes are coherent with the scale of electron-donor power of the R substituents; otherwise, this scale does not match the degree of Fe → N π-back-donation and the Fe–N bond energies, which were elucidated in (2–7)CF3SO3 by DFT calculations.

The catalytic potential of a large series of easily available metal carbamates (based on thirteen different non-precious metal elements) was explored for the first time in the coupling reaction between 2-aryl-aziridines and carbon dioxide, working under solventless and ambient conditions and using tetraalkylammonium halides as co-catalysts. The straightforward synthesis of novel [NbCl3(O2CNEt2)2], NbCl, and [NbBr3(O2CNEt2)2], NbBr, is reported. The niobium complex NbCl, in combination with NBu4I, emerged as the best catalyst of the overall series to convert aziridines with small N-alkyl substituents into the corresponding 5-aryl-oxazolidin-2-ones.

Carbonation of natural α-amino acids in water and subsequent cyclization with (2-bromo-1-arylethyl)dimethylsulfonium bromides led selectively to a family of 2-oxazolidinonyl derivatives, which were isolated without the needing of purification. Analogous conjugation of the 2-oxazolidinone skeleton with amino acids was previously realized by complicated and narrow-scope routes, whereby the amino acid core is built stepwise. Deprotonation of some of the products afforded the corresponding water-soluble carboxylates, while a straightforward, proof of concept esterification reaction of the carboxylic acid group yielded a menthol-alanine-oxazolidinone conjugate.