636 research outputs found
Glyoxal 4-nitrophenylhydrazone : triple helices linked into a three-dimensional channel structure
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Four related benzazepine derivatives in a reaction pathway leading to a benzazepine carboxylic acid : hydrogen-bonded assembly in zero, one, two and three dimensions
The authors thank ‘Centro de Instrumentacion Cientıfico-Tecnica of Universidad de Jaen’ and the staff for data collection. AP, SAG and CMS thank Colciencias for financial support (grant No. 1102–521–28229). JC thanks the Consejerıa de Innovacion, Ciencia y Empresa (Junta de Andalucıa, Spain) and the Universidad de Jaen for financial support.(2R*,4S*)-Methyl 2,3,4,5-tetrahydro-1,4-epoxy-1H-benz[b]azepine-2-carboxylate, C12H13NO3, (I), and its reduction product (2R*,4S*)-methyl 4-hydroxy-2,3,4,5-tetrahydro-1H-benz[b]azepine-2-carboxylate, C12H15NO3, (II), both crystallize as single enantiomers in the space group P212121, while the hydrolysis product (2RS,4SR)-4-hydroxy-2,3,4,5-tetrahydro-1H-benz[b]azepine-2-carboxylic acid, C11H13NO3, (III), and the lactone (2RS,5SR)-8-(trifluoromethoxy)-5,6-dihydro-1H-2,5-methanobenz[e][1,4]oxazocin-3(2H)-one, C12H10F3NO3, (IV), both crystallize as racemic mixtures in the space group P21/c. The molecules of compound (IV) are linked into centrosymmetric R22(10) dimers by N-HO hydrogen bonds, and those of compound (I) are linked into chains by C-H(arene) hydrogen bonds. A combination of O-HO and O-HN hydrogen bonds links the molecules of compound (III) into sheets containing equal numbers of R44(14) and R44(26) rings, and a combination of C-H(arene) hydrogen bonds and three-centre O-H(N,O) hydrogen bonds links the molecules of compound (II) into a three-dimensional framework structure. Comparisons are made with some related compounds.Publisher PDFPeer reviewe
Hydrogen bonding in C-methylated nitroanilines : the three-dimensional framework structure of 2-methyl-4-nitroaniline
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A triclinic polymorph of benzanilide : disordered molecules form hydrogen-bonded chains
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2,6-Diiodo-4-nitrophenol, 2,6-diiodo-4-nitrophenyl acetate and 2,6-diiodo-4-nitroanisole: interplay of hydrogen bonds, iodo-nitro interactions and aromatic [pi]-[pi]-stacking interactions to give supramolecular structures in one, two and three dimensions
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Hydrogen bonding in substituted nitroanilines : isolated nets in 1,3-diamino-4-nitrobenzene and continuously interwoven nets in 3,5-dinitroaniline
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How do hospitals respond to feedback about blood transfusion practice? A multiple case study investigation
National clinical audits play key roles in improving care and driving system-wide change. However, effects of audit and feedback depend upon both reach (e.g. relevant staff receiving the feedback) and response (e.g. staff regulating their behaviour accordingly). This study aimed to investigate which hospital staff initially receive feedback and formulate a response, how feedback is disseminated within hospitals, and how responses are enacted (including barriers and enablers to enactment). Using a multiple case study approach, we purposively sampled four UK hospitals for variation in infrastructure and resources. We conducted semi-structured interviews with staff from transfusion-related roles and observed Hospital Transfusion Committee meetings. Interviews and analysis were based on the Theoretical Domains Framework of behaviour change. We coded interview transcripts into theoretical domains, then inductively identified themes within each domain to identify barriers and enablers. We also analysed data to identify which staff currently receive feedback and how dissemination is managed within the hospital. Members of the hospital’s transfusion team initially received feedback in all cases, and were primarily responsible for disseminating and responding, facilitated through the Hospital Transfusion Committee. At each hospital, key individuals involved in prescribing transfusions reported never having received feedback from a national audit. Whether audits were discussed and actions explicitly agreed in Committee meetings varied between hospitals. Key enablers of action across all cases included clear lines of responsibility and strategies to remind staff about recommendations. Barriers included difficulties disseminating to relevant staff and needing to amend feedback to make it appropriate for local use. Appropriate responses by hospital staff to feedback about blood transfusion practice depend upon supportive infrastructures and role clarity. Hospitals could benefit from support to disseminate feedback systematically, particularly to frontline staff involved in the behaviours being audited, and practical tools to support strategic decision-making (e.g. action-planning around local response to feedback)
Poly[[chlorido-(1,10-phenanthroline-κ2N,N′)copper(II)]-μ3-1,1,3,3-tetra-cyano-2-eth-oxy-propenido- κ3N:N′:N′′] : coordination polymer sheets linked into bilayers by hydrogen bonds
The authors acknowledge the Algerian DG–RSDT (Direction Generale de la Recherche Scientifique et du Developpement Technologique) and the Algerian ATRST (Agence Thematique de Recherche en Sciences et Technologie; PNR project) for financial support. ZS thanks Sandra Lebaroud for her help in preparing the manuscript and the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.In the title compound, [Cu(C9H5N4O)Cl(C12H8N2)] n or [Cu(tcnoet)Cl(phen)] n , where phen is 1,10-phenanthroline and tcnoet is 1,1,3,3-tetra-cyano-2-eth- oxy-propenide, the axially elongated (4 + 2) coordination polyhedron around the CuII centre contains N atoms from three different tcnoet ligands. The resulting coordination polymer takes the form of sheets which are linked in pairs by a single C - H⋯N hydrogen bond to form bilayers. The bond lengths provide evidence for significant bond fixation in the phen ligand and extensive electronic delocalization in the tcnoet ligand, where the two -C(CN)2 units are rotated, in conrotatory fashion, out of the plane of the central C3O fragment.Publisher PDFPeer reviewe
Historical aspects of ground beetles (Carabus) and large diving beetles (Dytiscinae) distribution in Slovenia
V zadnjih desetletjih je v Evropi vse bolj opazno upadanje specializiranih in redkih vrst velikih krešičev (Carabus) in velikih kozakov (Dytiscinae), zato je bil naš namen ugotoviti trend razširjenosti in stopnjo ogroženosti obeh izbranih skupin na območju Slovenije. Na podlagi zgodovinskih in recentnih podatkov smo izdelali karte zgodovinske razširjenosti posameznih vrst in jim glede na zmanjšanje območij razširjenosti pripisali kategorije ogroženosti. Analizirali smo podatke za 25 vrst velikih krešičev in 16 vrst velikih kozakov. Velik delež vrst obeh skupin hroščev je v upadu, vendar je izginjanje velikih kozakov zaradi uničevanja vodnih okolij izrazitejše. Na trenutnem Rdečem seznamu ogroženih vrst so le 3 vrste iz vsake od izbranih skupin, naši rezultati pa so pokazali, da bi morali na seznam uvrstiti dodatnih 14 vrst velikih krešičev in 11 vrst velikih kozakov. Najbolj izginjajo veliki krešiči, ki so vezani na negozdna okolja, na zrele, negospodarske gozdove ali na vlažne gozdove, med velikimi kozaki pa vrste, vezane na šotna barja in manjša zarasla vodna telesa. Razlika v trendu razširjenosti med stenotopnimi in evritopnimi vrstami je bila značilna le pri velikih kozakih. Nekaj vrst iz obeh skupin je v zadnjih desetletjih na območju Slovenije že izginilo, zato so potrebne intenzivne ekološke raziskave preostalih vrst in nujno čimprejšnje oblikovanje učinkovitih ukrepov varstva.In the past few decades, there has been a sharp decline in specialised and rare species of both ground beetles (Carabus) and great diving beetles (Dytiscinae) throughout Europe. Our aim was to determine the distribution trends of chosen species and their conservation status in Slovenia. Based on historical and recent data, distribution maps for each species have been made. Extensive data for 25 species of genus Carabus and 16 species of diving beetles were analysed. The reduction in distribution area sizes was used to evaluate the decline of each species in Slovenia and for assigning them to different categories of threat status. A significant number of species from both beetle groups are in declinehowever, due to destruction of suitable water habitats, the disappearing rate of diving beetles is higher. Only 3 species from each of the chosen groups of beetles are currently on the Red list of threatened species in Slovenia, and based on our results, at least 14 species of ground beetles and 11 species of diving beetles should be added to the list. Open habitat species of ground beetles, ground beetles that are dependent on mature, unmanaged forests, and diving beetles that prefer peat bogs or small, strongly vegetated ponds, were found to be the most endangered. The difference between stenotopic and eurytopic species was significant only in the case of diving beetles. A few species from both groups of beetles have already disappeared from Slovenia in the last few decades, therefore intensive ecological studies of the remaining species and immediate effective conservation strategies are essential
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