60 research outputs found
An expanded MIL-53-type coordination polymer with a reactive pendant ligand
The authors acknowledge the University of Warwick Undergraduate Research Support Scheme for award of a bursary to TWC. The EPSRCâs UK National Crystallography Service at the University of Southampton is thanked for one of the data sets. The UK 850 MHz solid-state NMR Facility was funded by EPSRC and BBSRC (contract reference PR140003), as well as the University of Warwick including via part funding through Birmingham Science City Advanced Materials Projects 1 and 2 supported by Advantage West Midlands (AWM) and the European Regional Development Fund (ERDF). SEA would like to thank the ERC (EU FP7 Consolidator Grant 614290 âEXONMRâ).A coordination polymer with a structure isoreticular to MIL-53, but containing a divalent metal cation (Co2+ or Mg2+) and a coordinating 4-styrylpyridine-N-oxide ligand, crystallises under solvothermal conditions; the pendant ligand can be brominated, with evidence from powder X-ray diffraction, element mapping and 81Br solid- state NMR for this post-synthesis modification.Publisher PDFPeer reviewe
Peri-substituted phosphorus-tellurium systems â an experimental and theoretical investigation of the PâââTe through-space interaction
The authors are thankful to the EPSRC, the EPSRC National Mass Spectrometry Service Centre (NMSSC) Swansea, the School of Chemistry St. Andrews, and EaStCHEM for support.A series of peri-substituted phosphorus-tellurium systems RâTeâAcenapâPR2 (Râ = Ph, p-An, Nap, Mes, Tip; R = iPr, Ph) exhibiting large âthrough spaceâ spin-spin coupling constants and the âonsetâ of three-centre four-electron type interactions are presented. The influence of the substituents at the phosphorus and tellurium atoms as well as their behavior upon oxidation (with S, Se) or metal-coordination (Pt, Au) is discussed using NMR spectroscopy, single crystal X-ray diffraction, and advanced DFT studies including NBO, AIM and ELI-D analyses.PostprintPeer reviewe
Alkaline-Earth Rhodium Hydroxides: Synthesis, Structures, and Thermal Decomposition to Complex Oxides
The rhodium (III) hydrogarnets Ca3Rh2(OH)12 and Sr3Rh2(OH)12 crystallise as polycrystalline powders under hydrothermal conditions at 200°C from RhCl3·3H2O and either Ca(OH)2 or Sr(OH)2 in either 12 M NaOH or KOH. Rietveld refinements against synchrotron powder X-ray diffraction (XRD) data allow the first crystal structures of the two materials to be determined. If BaO2 is used as a reagent and the concentration of hydroxide increased to hydroflux conditions (excess NaOH) then single crystals of a new complex rhodium hydroxide, BaNaRh(OH)6, are formed in a phase-pure sample, with sodium included from the flux. Structure solution from single-crystal XRD data reveals isolated octahedral Rh centres that share hydroxides with 10-coordinate Ba and two independent 8-coordinate Na sites. 23Na magic-angle spinning NMR confirms the presence of the two crystallographically distinct Na sites and also verifies the diamagnetic nature of the sample, expected for Rh(III). The thermal behaviour of the hydroxides on heating in air was investigated using X-ray thermodiffractometry, showing different decomposition pathways for each material. Ca3Rh2(OH)12 yields CaRh2O4 and CaO above 650°C, from which phase-pure CaRh2O4 is isolated by washing with dilute nitric acid, a material previously only reported by high-pressure or high-temperature synthesis. Sr3Rh2(OH)12 decomposes to give a less crystalline material with a powder XRD pattern that is matched to the 2H-layered hexagonal perovskite Sr6Rh5O15, which contains mixed-valent Rh3+/4+, confirmed by Rh K-edge XANES spectroscopy. On heating BaNaRh(OH)6 a complex set of decomposition events takes place via transient phases
HOSPITAL PATIENT SAFETY ASSESSMENT EXEMPLIFIED BY THE STANDARDIZED MORTALITY RATES
Sigurnost bolesnika je vaĆŸni Äimbenik kvalitete zdravstvenog sustava, koji je i zakonski propisan. U Zakonu o kvaliteti zdravstvene zaĆĄtite i socijalne skrbi defi nirana je sigurnost zdravstvenog postupka, a u Pravilniku o standardima kvalitete zdravstvene zaĆĄtite i naÄinu njihove primjene navedeni su Pokazatelji sigurnosti (NeoÄekivani neĆŸeljeni dogaÄaji i Ostali neĆŸeljeni dogaÄaji). U Ostale neĆŸeljene dogaÄaje ubraja se i Stopa standardizirane bolniÄke smrtnosti. Ona je kvantitativni pokazatelj bolesnikove sigurnosti u bolniÄkom sustavu zdravstvene zaĆĄtite i prati se za smrtnost od akutnog infarkta miokarda, moĆŸdanog udara i akutnog pankreatitisa unutar 30 dana od prijama u bolnicu. Opisne liste za indikatore sigurnosti propisala je Agencija za kvalitetu u zdravstvu i socijalnoj skrbi. U KBC Sestre milosrdnice se Stope standardizirane bolniÄke smrtnosti redovito prate i analiziraju. Rezultati upuÄuju na primjenu dobre kliniÄke prakse u KBC Sestre milosrdnice i zadovoljavajuÄu razinu sigurnosti pacijenata od smrtnosti praÄene patologije.Patient safety is a legally prescribed, important quality factor of the healthcare system. The safety of medical procedures is defined in the Act on Healthcare Quality, while safety indicators (such as unexpected and other unwanted events) are depicted in the Healthcare Quality Standards and regulations on their usage. The list of safety indicators is determined by the Healthcare and Social Service Agency. Standardized Hospital Mortality Rate falls under âOther unwanted eventsâ, but is also a quantity indicator of patient safety in the hospital healthcare system where it monitors acute myocardial infarction, stroke and acute pancreatitis in the 30-day hospitalization period. At Sestre milosrdnice University Hospital Centre, this indicator has been monitored and analyzed on a regular basis. Monitoring results indicate good clinical practice, as well as a satisfying level of patient safety in relation to the pathology mortality monitored in the mentioned hospital
Polymorphism, weak interactions and phase transitions in chalcogen-phosphorus heterocycles
We would like to thank the ERC (EU FP7 Consolidator Grant 614290 âEXONMRâ) and EPSRC for computational support through the Collaborative Computational Project on NMR Crystallography (CCP-NC), via EP/M022501/1 and EP/J010510/1. SEA would like to thank the Royal Society and the Wolfson Foundation for a merit award. The research data (and/or materials) supporting this publication can be accessed at DOI: 10.17630/d0b365a1-b647-4556-b6f8-24d99d0c7a8a.A series of PâEâcontaining heterocycles (E=chalcogen) with aromatic backbones were synthesised and characterised by singleâcrystal and powder XRD, microanalysis and mass spectrometry. Solutionâ and solidâstate 31P and 77Se NMR spectroscopy revealed significant differences between the NMR parameters in solution and in the solid state, related to conformational changes in the molecules. Many compounds were shown to exhibit a number of different polymorphic structures (identified by singleâcrystal XRD), although the bulk material studied by solidâstate NMR spectroscopy often contained just one major polymorph. For the unoxidised heterocycles, the presence of weak intermolecular J couplings was also investigated by DFT calculations.Publisher PDFPeer reviewe
Porous zinc and cobalt 2-nitroimidazolate frameworks with six-membered ring windows and a layered cobalt 2-nitroimidazolate polymorph
This work was supported by the European Community Seventh Framework Program (FP7/2007-2013) [grant agreement number 608490] (project M4CO2). A.O. would like to acknowledge the SCI for awarding a scholarship for her PhD research. G.M. thanks Institut Universitaire de France for its support. S.S. would like to thank the EPSRC for support EP/M506631/1. S.E.A would like to thank the Royal Society and Wolfson Foundation for a merit award.Polymorphs of Zn(2-nIm)2 (compound 1 ) and Co(2-nIm)2 (compounds 2 and 3 ) (2-nIm = 2-nitroimidazole) have been prepared by two routes: solvothermal synthesis and recrystallisation of ZIF-65(Zn/Co). Compounds 1 and 2 are isostructural, with a tetrahedrally-connected framework topology related to, but different from, that of tridymite (lonsdaleite). Single crystal X-ray diffraction analysis showed that in compound 1 (Pccn, Z = 8; a = 8.462(8) Ă
, b = 14.549(15) Ă
, c = 18.799(18) Ă
, V = 2314(4) Ă
3) there is rotational disorder for two of the three crystallographically-distinct linker types, which has been investigated computationally and by solid-state NMR spectroscopy. Detailed adsorption studies on a sample of 1 prepared by recrystallisation show 1.1 mmol g-1 uptake of CO2 at 0.1 bar (25 °C) with high affinity for CO2 over CH4 and N2 (adsorption enthalpies of 39.5, 26.0 and 18.5 kJ mol-1, respectively). A cobalt analogue (compound 2 ) with improved water stability (but lower porosity) has also been prepared. Changing the conditions of synthesis and recrystallisation gives rise to a cobalt 2-nitroimidazolate (Co(2-nIm)2, compound 3 ), which has a layered structure (I41/amd, a = 6.025(18) Ă
, c = 26.95(8) Ă
, V = 978.3(5) Ă
3) containing sheets of tetrahedrally-connected Co2+ cations composed of four membered rings, without porosity.PostprintPostprintPeer reviewe
Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial
SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87â1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98â1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87â1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication
Data underpinning Unusual Intermolecular âThrough-Spaceâ J Couplings in PâSe Heterocycles
Investigating the use of first-principles calculations for NMR studies of disordered in the solid state (thesis data)
This dataset contains the metadata for this thesis, including a folder "Figures" containing a .pdf version of each figure contained in this thesis, which can be opened using Preview or Adobe Illustrator. The folder "Research metadata" contains all the relevant metadata associated with this thesis, including metadata for NMR spectra and first-principles calculations. NMR spectra metadata can be viewed using Topspin software. Files including .castep, .magres, .cell, .param) can be opened using TextEdit. .cif and .res files can be opened using TextEdit or CrystalMaker software
An NMR Crystallographic Investigation of the Relationships Between the Crystal Structure and 29Si Isotropic Chemical Shift in Silica Zeolites (dataset)
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