Synthesis, structure, and photophysical properties of platinum(II) (N, C, N) pincer complexes derived from purine nucleobases

The synthesis of a series of Pt{κ3-N,C,N′-[L]}X (X = Cl, RC≡C) pincer complexes derived from purine and purine nucleosides is reported. In these complexes, the 6-phenylpurine skeleton provides the N,C-cyclometalated fragment, whereas an amine, imine, or pyridine substituent of the phenyl ring supplies the additional N′-coordination point to the pincer complex. The purine N,C-fragment has two coordination positions with the metal (N1 and N7), but the formation of the platinum complexes is totally regioselective. Coordination through the N7 position leads to the thermodynamically favored [6.5]-Pt{κ3-N7,C,N′-[L]}X complexes. However, the coordination through the N1 position is preferred by the amino derivatives, leading to the isomeric kinetic [5.5]-Pt{κ3-N1,C,N′-[L]}X complexes. Extension of the reported methodology to complexes having both pincer and acetylide ligands derived from nucleosides allows the preparation of novel heteroleptic bis-nucleoside compounds that could be regarded as organometallic models of Pt-induced interstrand cross-link. Complexes having amine or pyridine arms are green phosphorescence emitters upon photoexcitation at low concentrations in CH2Cl2 solution and in poly(methyl methacrylate) (PMMA) films. They undergo self-quenching at high concentrations due to molecular aggregation. The presence of intermolecular π–π stacking and weak Pt···Pt interactions was also observed in the solid state by X-ray diffraction analysis

A tactile model of the night summer northern sky for the teaching of astronomy to the BVI

Astroaccesible is an outreach project hosted by the Instituto de Astrof\'{\i}sica de Andaluc\'{\i}a - CSIC aimed at the teaching and popularisation of the astronomy among all publics independently of their capabilities and abilities, paying special attention to the collective of blind and visually impaired (BVI). Among the different strategies and resources using in our project, we have developed new 3D models representing in relief some of the stars, constellations and deep sky objects that can be observed during night from the Northern hemisphere in spring and summer. These models can be used by BVI to transmit to them the spatial configuration of the sky during night, but can be also used as an additional resource for all kind of publics to complement their sensorial experience. We also describe additional resources based on sounds that can also be employed to get deeper into this multisensorial experience. Finally, we summarize some of the activities and the context in which this new material has been used in the last 2 years.Comment: 6 pages, 2 figures. To appear as proceeding of the 15th Scientific Meeting of the Spanish Astronomical Societ

Osmium Catalysts for Acceptorless and Base-Free Dehydrogenation of Alcohols and Amines: Unusual Coordination Modes of a BPI Anion

A novel type of catalyst precursors for the dehydrogenation of hydrogen carriers based on organic liquids has been discovered. Complexes OsH6(PiPr3)2 (1) and OsH(OH)(CO)(PiPr3)2 (2) react with 1,3-bis(6'-methyl-2'-pyridylimino)isoindoline (HBMePI) to give OsH3{¿2-Npy,Nimine-(BMePI)}(PiPr3)2 (3) and OsH{¿2-Npy,Nimine-(BMePI)}(CO)(PiPr3)2 (4). The unprecedented ¿2-Npy,Nimine coordination mode of BMePI is thermodynamically preferred with Os(IV) and Os(II) metal fragments and allows for preparation of BMePI-based dinuclear metal cations. Treatment of OsH2Cl2(PiPr3)2 (5) with 0.5 equiv of HBMePI in the presence of KOtBu affords the chloride salt of the bis(osmium(IV)) dinuclear cation [{OsH3(PiPr3)2}2{µ-(¿2-Npy,Nimine)2-BMePI}]+ (6). Related homoleptic bis(osmium(II)) complexes have been also synthesized. Complex 4 reacts with the bis(solvento) [OsH(CO){¿1-O-[OCMe2]2}(PiPr3)2]BF4 to give [{OsH(CO)(PiPr3)2}2{µ-(¿2-Npy,Nimine)2-BMePI}]BF4 (7), whereas the addition of 0.5 equiv of HBMePI to {OsCl(¿6-C6H6)}2(µ–Cl)2 (8) affords [{OsCl(¿6-C6H6)}2{µ-(¿2-Npy,Nimine)2-BMePI}]Cl (9). The reactions of 4 with 8 and {OsCl(¿6-p-cymene)}2(µ–Cl)2 (10) lead to the heteroleptic cations [(PiPr3)2(CO)HOs{µ-(¿2-Npy,Nimine)2-BMePI}OsCl(¿6-arene)]+ (arene = C6H6 (11), p-cymene (12)). The electronic structrure and electrochemical properties of the dinuclear complexes were also studied. Complexes 3 and 4 are efficient catalyst precursors for the acceptorless and base-free dehydrogenation of secondary and primary alcohols and cyclic and lineal amines. The primary alcohols afford aldehydes. The amount of H2 released per gram of heterocycle depends upon the presence of a methyl group adjacent to the nitrogen atom, the position of the nitrogen atom in the heterocycle, and the size of the heterocycle

Occupational injuries in workers of a Spanish bank

BACKGROUND: In 2017, 69 108 work-related traffic injuries with medical leave were documented, constituting 12% of all occupational injuries (OI) in Spain. AIMS: The aim of this study was to describe OI within a Spanish bank company during 2017. METHODS: A cross-sectional analysis was conducted using the company's mandatory OI records, presenting data in both absolute (n) and relative (%) frequencies. The chi-square test was employed for comparisons. RESULTS: Among the company's 10 399 employees, 176 OI cases were recorded. Most were minor musculoskeletal incidents, with one severe myocardial infarction and one mild anxiety episode. Lower limb injuries were the most prevalent. Injuries of the trunk (P < 0.001), neck (P < 0.05), and upper limbs (P < 0.001) were linked to workplace factors. Approximately 62% of OI occurred outside the workplace and resulted in more extended medical leave (P < 0.01). Traffic-related injuries accounted for 39% of OI cases and caused 49% of days lost due to OI (P < 0.001).Female gender (P < 0.001) and age over 40 years (P < 0.05) were significantly associated with OI. CONCLUSIONS: In our study, musculoskeletal injuries were the most common, with a single cardiovascular event being the most severe. OI occurring outside the workplace was more frequent and led to longer medical leaves. Notably, traffic-related injuries were especially significant, exceeding official statistics 4-fold

Using radio astronomical receivers for molecular spectroscopic characterization in astrochemical laboratory simulations: A proof of concept

We present a proof of concept on the coupling of radio astronomical receivers and spectrometers with chemical reactorsand the performances of the resulting setup for spectroscopy and chemical simulations in laboratory astrophysics. Several experiments including cold plasma generation and UV photochemistry were performed in a 40\,cm long gas cell placed in the beam path of the Aries 40\,m radio telescope receivers operating in the 41-49 GHz frequency range interfaced with fast Fourier transform spectrometers providing 2 GHz bandwidth and 38 kHz resolution. The impedance matching of the cell windows has been studied using different materials. The choice of the material and its thickness was critical to obtain a sensitivity identical to that of standard radio astronomical observations. Spectroscopic signals arising from very low partial pressures of CH3OH, CH3CH2OH, HCOOH, OCS,CS, SO2 (<1E-03 mbar) were detected in a few seconds. Fast data acquisition was achieved allowing for kinetic measurements in fragmentation experiments using electron impact or UV irradiation. Time evolution of chemical reactions involving OCS, O2 and CS2 was also observed demonstrating that reactive species, such as CS, can be maintained with high abundance in the gas phase during these experiments.Comment: Accepted for publication in Astronomy and Astrophysics in September 21, 2017. 16 pages, 18 figure

Genetic Association between ACE2 (rs2285666 and rs2074192) and TMPRSS2 (rs12329760 and rs2070788) Polymorphisms with Post-COVID Symptoms in Previously Hospitalized COVID-19 Survivors

The aim of the study was to identify the association between four selected COVID-19 polymorphisms of ACE2 and TMPRSS2 receptors genes with the presence of long-COVID symptomatology in COVID-19 survivors. These genes were selected as they associate with the entry of the SARS-CoV-2 virus into the cells, so polymorphisms could be important for the prognoses of long-COVID symptoms. Two hundred and ninety-three (n = 293, 49.5% female, mean age: 55.6 ± 12.9 years) individuals who had been previously hospitalized due to COVID-19 were included. Three potential genotypes of the following single nucleotide polymorphisms (SNPs) were obtained from non-stimulated saliva samples of participants: ACE2 (rs2285666), ACE2 (rs2074192), TMPRSS2 (rs12329760), TMPRSS2 (rs2070788). Participants were asked to self-report the presence of any post-COVID defined as a symptom that started no later than one month after SARS-CoV-2 acute infection and whether the symptom persisted at the time of the study. At the time of the study (mean: 17.8, SD: 5.2 months after hospital discharge), 87.7% patients reported at least one symptom. Fatigue (62.8%), pain (39.9%) or memory loss (32.1%) were the most prevalent post-COVID symptoms. Overall, no differences in long-COVID symptoms were dependent on ACE2 rs2285666, ACE2 rs2074192, TMPRSS2 rs12329760, or TMPRSS2 rs2070788 genotypes. The four SNPs assessed, albeit previously associated with COVID-19 severity, do not predispose for developing long-COVID symptoms in people who were previously hospitalized due to COVID-19 during the first wave of the pandemic

Is there an association between ACTN3 R577X polymorphism and muscle power phenotypes in young, non-athletic adults?

We investigated the association between ACTN3 R577X polymorphism and jumping (vertical squat and counter-movement jump tests) and sprint ability (30 m dash) in non-athletic, healthy young adults [N=284 (217 male), mean (SD) age: 21 (2) years]. We analyzed the differences in the study phenotypes among ACTN3 R577X genotypes by one-way analysis of covariance before and after adjusting for sex, age, weight and height (confounders). We also compared the genotype and allele frequencies between those with the best and worst results in the aforementioned tests (≥90th vs 0.05). In summary, α-actinin-3 deficiency does not negatively influence the ability to generate explosive leg muscle power in a young non-athletic population