Journal articles: 'Multiple metal centres'

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Cheng, Howard, Fazlul Huq, and Philip Beale. "Studies on new homonuclear and heteronuclear metal complexes with multiple centres." Journal of Inorganic Biochemistry 96, no. 1 (July 2003): 115. http://dx.doi.org/10.1016/s0162-0134(03)80587-1.

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Turner, David R., M. B. Hursthouse, M. E. Light, and Jonathan W. Steed. "Linear distortion of octahedral metal centres by multiple hydrogen bonds in modular ML4 systems." Chemical Communications, no. 12 (2004): 1354. http://dx.doi.org/10.1039/b402884h.

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Bingham, Stephen J., Daniel Wolverson, and Andrew J. Thomson. "Coherent Raman detected electron spin resonance spectroscopy of metalloproteins: linking electron spin resonance and magnetic circular dichroism." Biochemical Society Transactions 36, no. 6 (November 19, 2008): 1187–90. http://dx.doi.org/10.1042/bst0361187.

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The simultaneous excitation of paramagnetic molecules with optical (laser) and microwave radiation in the presence of a magnetic field can cause an amplitude, or phase, modulation of the transmitted light at the microwave frequency. The detection of this modulation indicates the presence of coupled optical and ESR transitions. The phenomenon can be viewed as a coherent Raman effect or, in most cases, as a microwave frequency modulation of the magnetic circular dichroism by the precessing magnetization. By allowing the optical and magnetic properties of a transition metal ion centre to be correlated, it becomes possible to deconvolute the overlapping optical or ESR spectra of multiple centres in a protein or of multiple chemical forms of a particular centre. The same correlation capability also allows the relative orientation of the magnetic and optical anisotropies of each species to be measured, even when the species cannot be obtained in a crystalline form. Such measurements provide constraints on electronic structure calculations. The capabilities of the method are illustrated by data from the dimeric mixed-valence CuA centre of nitrous oxide reductase (N2OR) from Paracoccus pantotrophus.

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Xiao, Zhiguang, and Anthony G. Wedd. "Metallo-oxidase Enzymes: Design of their Active Sites." Australian Journal of Chemistry 64, no. 3 (2011): 231. http://dx.doi.org/10.1071/ch10428.

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Multi-copper oxidases are a large family of enzymes prevalent in all three domains of life. They couple the one-electron oxidation of substrate to the four-electron reduction of dioxygen to water and feature at least four Cu atoms, traditionally divided into three sites: T1, T2, and (binuclear) T3. The T1 site catalyzes substrate oxidation while a trinuclear cluster (comprising combined T2 and T3 centres) catalyzes the reduction of dioxygen. Substrate oxidation at the T1 Cu site occurs via an outer-sphere mechanism and consequently substrate specificities are determined primarily by the nature of a substrate docking/oxidation (SDO) site associated with the T1 Cu centre. Many of these enzymes ‘moonlight’, i.e. display broad specificities towards many different substrates and may have multiple cellular functions. A sub-set are robust catalysts for the oxidation of low-valent transition metal ions such as FeII, CuI, and MnII and are termed ‘metallo-oxidases’. They play essential roles in nutrient metal uptake and homeostasis, with the ferroxidase ceruloplasmin being a prominent member. Their SDO sites are tailored to facilitate specific binding and facile oxidation of these low-valent metal ions and this is the focus of this review.

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Zhang, J. C., J. F. Wang, Y. T. Wang, M. Wu, J. P. Liu, J. J. Zhu, and H. Yang. "Effect of trimethylgallium flow on the structural and optical properties of InGaN/GaN multiple quantum wells." Journal of Applied Crystallography 37, no. 3 (May 11, 2004): 391–94. http://dx.doi.org/10.1107/s0021889804005217.

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InGaN/GaN multiple quantum wells (MQWs) are grown by metal-organic chemical vapour deposition on (0001) sapphire substrates. Triple-axis X-ray diffraction (TXRD) and photoluminescence (PL) spectra are used to assess the influence of trimethylgallium (TMGa) flow on structural defects, such as dislocations and interface roughness, and the optical properties of the MQWs. In this paper, a method, involving an ω scan of every satellite peak of TXRD, is presented to measure the mean dislocation density of InGaN/GaN MQWs. The experimental results show that under certain conditions which keep the trimethlyindium flow constant, dislocation density and interface roughness decrease with the increase of TMGa flow, which will improve the PL properties. It can be concluded that dislocations, especially edge dislocations, act as non-radiative recombination centres in InGaN/GaN MQWs. Also noticed is that changing the TMGa flow has more influence on edge dislocations than screw dislocations.

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Pidko, Evgeny A., Emiel J. M. Hensen, and Rutger A. van Santen. "Self-organization of extraframework cations in zeolites." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 468, no. 2143 (March 7, 2012): 2070–86. http://dx.doi.org/10.1098/rspa.2012.0057.

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Structural properties of a series of mordenite and ZSM-5 zeolites with different framework Al distribution modified with oxygenated extraframework Ga, Zn, Al, Cu and Fe complexes were investigated by means of periodic density functional theory calculations. It is demonstrated that mononuclear oxygenated and hydroxylated cationic metal complexes in high-silica zeolites tend to self-organize into binuclear complexes. In the cases of Ga- and Fe-modified zeolites, it is shown that the catalytic activity of the most stable binuclear extraframework cations is much higher than that of the hypothetical very reactive mononuclear counterparts. This is due to a weaker binding of reaction intermediates and easier regeneration of the initial active complexes in the course of the catalytic reaction. The formation of multiple-charged binuclear oxygenated metal species in zeolites is a general phenomenon. It does not require a specific distribution of the equivalent number of negative framework charges that compensate for the positive charge of the cationic complexes. The location and the stability of cationic complexes in zeolite micropores are mainly determined by the coordination properties of the metal centres.

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Kassim, Muhammad Arif, Ubaidullah H. M. Yassin, Ai Ling Tan, Anwar Usman, and Malai Haniti S. A. Hamid. "[1-(Pyrazin-2-yl)ethylidene]hydrazine: a new multitopic ligand for the design of hybrid molecular frameworks." Acta Crystallographica Section C Structural Chemistry 74, no. 4 (March 7, 2018): 424–27. http://dx.doi.org/10.1107/s2053229618003273.

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Hydrazones and their derivatives are closely related to imine compounds and are potential antimicrobial agents. They have also found application in supramolecular chemistry as multitopic ligands to link multiple metal centres for the design of hybrid molecular frameworks. The molecule of the title compound, C6H8N4, consists of an imine linkage with an N—N bond length of 1.3540 (14) Å. This asymmetric compound is nearly planar and adopts an E configuration about the azomethine C=N double bond. In the solid state, there are two intermolecular N—H...N interactions that interconnect the molecules into a two-dimensional network. The three-dimensional arrangement of the crystal packing is further stabilized by intermolecular π–π interactions interconnecting the centroids of the heterocyclic rings.

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Guo, Wei, Li-Qiang Han, and Ya-Mei Guo. "Transition-Metal Supramolecular Complexes with 2-Phenylacetate and a Bent Dipyridyl Ligand: In Situ Hydrothermal Syntheses, Crystal Structures, and Photoluminescent Properties." Australian Journal of Chemistry 66, no. 5 (2013): 539. http://dx.doi.org/10.1071/ch12483.

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This work presents seven CoII, CdII, ZnII, MnII, and NiII supramolecular complexes synthesised by hydrothermal reactions from a bent dipyridyl ligand 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (4-bpo) and 2-phenylmalonic acid (2-phmalH2). Interestingly, the in situ generation of 2-phenylacetic acid (Hpa) by decarboxylation of the 2-phenylmalonic acid precursor is observed in all the complexes. Single-crystal X-ray diffraction reveals that these complexes display a variety of 1D (for 2–7) and monomeric (for 1) coordination motifs, which are further extended into polymeric supramolecular architectures by multiple secondary interactions, such as hydrogen bonding and aromatic stacking. The results evidently demonstrate that the structures of 1–7 are significantly affected by the metal centres and the counter anions of inorganic salts. The photoluminescence properties of complexes 1–7 have also been investigated and discussed.

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Song, Feijie, Teng Zhang, Cheng Wang, and Wenbin Lin. "Chiral porous metal-organic frameworks with dual active sites for sequential asymmetric catalysis." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 468, no. 2143 (March 14, 2012): 2035–52. http://dx.doi.org/10.1098/rspa.2012.0100.

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Metal-organic frameworks (MOFs) are a class of organic–inorganic hybrid materials built from metal-connecting nodes and organic-bridging ligands. They have received much attention in recent years owing to the ability to tune their properties for potential applications in various areas. Properly designed MOFs with uniform, periodically aligned active sites have shown great promise in catalysing shape-, size-, chemo-, regio- and stereo-selective organic transformations. This study reports the synthesis and characterization of two chiral MOFs (CMOFs 1 and 2 ) that are constructed from Mn-salen-derived dicarboxylic acids [salen is ( R , R )- N , N ′-bis(5- tert -butylsalicylidene)-1,2-cyclohexanediamine], bis(4-vinylbenzoic acid)-salen manganese(III) chloride (H 2 L 4 ) or bis(benzoic acid)-salen manganese(III) chloride (H 2 L 3 ) and [Zn 4 (μ 4 -O)(O 2 CR) 6 ] or [Zn 5 (H 2 O) 2 (μ 3 -OH) 2 (O 2 CR) 8 ] secondary building units (SBUs), respectively. The SBUs in CMOF- 1 are connected by the linear ditopic Mn-salen-derived linkers to construct a fourfold interpenetrated isoreticular MOF (IRMOF) structure with pcu topology. In CMOF- 2 , the Mn-salen centres dimerize in a cross-linking way to form a diamondoid structure with threefold interpenetration. CMOF- 1 was examined for highly regio- and stereo-selective tandem alkene epoxidation/epoxide ring-opening reactions by using the Mn-salen andZn 4 (μ 4 -O)(carboxylate) 6 active sites, respectively. Our work demonstrated the potential utility of chiral MOFs with multiple active sites in the efficient synthesis of complex molecules with excellent regio- and stereo-controls

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Wilk, Magdalena, Jan Janczak, and Veneta Videnova-Adrabinska. "Poly[aqua[μ3-(pyridin-1-ium-3,5-diyl)diphosphonato-κ3O:O′:O′′][μ2-(pyridin-1-ium-3,5-diyl)diphosphonato-κ2O:O′]calcium(II)]." Acta Crystallographica Section C Crystal Structure Communications 68, no. 2 (January 25, 2012): m41—m44. http://dx.doi.org/10.1107/s0108270112001461.

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The rigid organic ligand (pyridine-3,5-diyl)diphosphonic acid has been used to create the title novel three-dimensional coordination polymer, [Ca(C5H6NO6P2)2(H2O)]n. The six-coordinate calcium ion is in a distorted octahedral environment, formed by five phosphonate O atoms from five different (pyridin-1-ium-3,5-diyl)diphosphonate ligands, two of which are unique, and one water O atom. Two crystallographically independent acid monoanions,L1 andL2, serve to link metal centres using two different coordination modes,viz.η2μ2and η3μ3, respectively. The latter ligand,L2, forms a strongly undulated two-dimensional framework parallel to the crystallographicbcplane, whereas the former ligand,L1, is utilized in the formation of one-dimensional helical chains in the [010] direction. The two sublattices ofL1 andL2 interweave at the Ca2+ions to form a three-dimensional framework. In addition, multiple O—H...O and N—H...O hydrogen bonds stabilize the three-dimensional coordination network. Topologically, the three-dimensional framework can be simplified as a very unusual (2,3,5)-connected three-nodal net represented by the Schläfli symbol (4·82)(4·88·10)(8).

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Sundermeyer, Jörg, Klaus Weber, and Oliver Nürnberg. "(α-Triphenylphosphonio)methylidene imido complexes of molybdenum, tungsten and rhenium: the first complexes exhibiting metal–ligand multiple-bonding with two carbon as well as two nitrogen centres." J. Chem. Soc., Chem. Commun., no. 22 (1992): 1631–33. http://dx.doi.org/10.1039/c39920001631.

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Sachs, Michael, Benjamin Poulter, Zhaoyuan Yang, Niranjan Govind, Robert Schoenlein, Munira Khalil, and Elisa Biasin. "Impact of Solvent-Solute Hydrogen Bonding on Ultrafast Electron Transfer in a Trimetallic Iron-Ruthenium Complex." ECS Meeting Abstracts MA2022-02, no. 48 (October 9, 2022): 1807. http://dx.doi.org/10.1149/ma2022-02481807mtgabs.

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Transition metal complexes (TMCs) are widely used as light absorbers and catalysts for photochemical energy conversion processes such as photocatalytic reactions in liquid environments. Of particular interest are TMCs which incorporate multiple bridged metal centres because they represent a step towards more complex supramolecular assemblies that can ultimately enable control of the charge flow in solution-based photo-redox processes. However, the development of design guidelines for such molecular assemblies is impeded by an incomplete understanding of the coupling between their electronic and nuclear dynamics, including the interplay of TMCs with their liquid environment upon photoexcitation. Probing the involved processes requires high spatial sensitivity towards electronic motion and the ability to capture atomic motion on ultrafast timescales – a combination which is not readily available for optical transient spectroscopic techniques. X-ray free electron lasers (XFELs) have revolutionized the field of ultrafast science in recent years. XFELs generate tuneable and extremely bright X-ray pulses with a typical pulse duration of <30 fs, which are well-suited as an element-specific probe of ultrafast electronic and atomic motion in molecules and materials.1,2 Applied to TMCs, XFEL probes are sensitive to the local electronic structure in such molecular systems as well as to intra- and inter-molecular structural reorganization at an atomic level.3 In this talk, I will present work on the interaction of a linear trimetallic cyanide-bridged iron-ruthenium complex (FeRuFe) with its solvent environment, carried out using the LCLS XFEL facility at SLAC National Accelerator Laboratory. The focus of this study lies on elucidating how photoinduced intramolecular electron transfer processes in FeRuFe are affected by hydrogen bonding interactions between its cyanide ligands and the surrounding solvent molecules. In water, such solvent-solute hydrogen bonding interactions are stronger for Fe(II) than Fe(III), leading to substantial changes in solute-solvent interactions upon photoinduced electron transfer between metal centres. The experiment is performed in a pump-probe geometry on a liquid jet, where a visible/near-infrared pump induces a metal-to-metal charge transfer (MMCT) between Ru and Fe which is followed by an ultrafast back-electron transfer (BET). The excited state dynamics are monitored using hard X-ray pulses as a function of time delay between the laser pump and the X-ray probe pulses. To resolve and correlate electronic and structural dynamics upon MMCT excitation, we simultaneously perform ultrafast Fe Kβ X-ray emission spectroscopy (XES) and X-ray solution scattering (XSS) measurements, where XES is sensitive to the oxidation and spin state of the Fe centres and XSS provides information on atomic motion in solute and solvent, as demonstrated in previous work on a similar system.4 To evaluate the effect of solute-solvent hydrogen bonding interactions on the electron transfer dynamics, we perform measurements in a series of solvents with different hydrogen bonding properties, including water, methanol, and acetonitrile. We find that the BET increases as a function of decreasing hydrogen bonding ability of the solvent, and that distinct signatures of solvation dynamics are present in the scattering data. The resulting molecular level understanding of solvent reorganization coupled to electron transfer demonstrates that the strength and type of solute-solvent interactions are a central factor in determining the outcome of photoinduced charge transfer processes in TMCs. References Bergmann, U. et al. Using X-ray free-electron lasers for spectroscopy of molecular catalysts and metalloenzymes. Nat. Rev. Phys. 3, 264–282 (2021). Schoenlein, R. et al. Recent advances in ultrafast X-ray sources. Philos. Trans. R. Soc. Math. Phys. Eng. Sci. 377, 20180384 (2019). Gaffney, K. J. Capturing photochemical and photophysical transformations in iron complexes with ultrafast X-ray spectroscopy and scattering. Chem. Sci. 12, 8010–8025 (2021). Biasin, E. et al. Direct observation of coherent femtosecond solvent reorganization coupled to intramolecular electron transfer. Nat. Chem. 13, 343–349 (2021).

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Li, Mingze, Jun Zhou, Guojun Zhou, Maxim S. Molokeev, Jing Zhao, Viktoriia Morad, Maksym V. Kovalenko, and Zhiguo Xia. "Hybrid Metal Halides with Multiple Photoluminescence Centers." Angewandte Chemie 131, no. 51 (November 4, 2019): 18843–48. http://dx.doi.org/10.1002/ange.201911419.

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Li, Mingze, Jun Zhou, Guojun Zhou, Maxim S. Molokeev, Jing Zhao, Viktoriia Morad, Maksym V. Kovalenko, and Zhiguo Xia. "Hybrid Metal Halides with Multiple Photoluminescence Centers." Angewandte Chemie International Edition 58, no. 51 (November 4, 2019): 18670–75. http://dx.doi.org/10.1002/anie.201911419.

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Mara, Michael W., Brian T. Phelan, Zhu-Lin Xie, Tae Wu Kim, Darren J. Hsu, Xiaolin Liu, Andrew J. S. Valentine, et al. "Unveiling ultrafast dynamics in bridged bimetallic complexes using optical and X-ray transient absorption spectroscopies." Chemical Science 13, no. 6 (2022): 1715–24. http://dx.doi.org/10.1039/d1sc05034f.

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Runčevski, Tomče, Matthew T. Kapelewski, Rodolfo M. Torres-Gavosto, Jacob D. Tarver, Craig M. Brown, and Jeffrey R. Long. "Adsorption of two gas molecules at a single metal site in a metal–organic framework." Chemical Communications 52, no. 53 (2016): 8251–54. http://dx.doi.org/10.1039/c6cc02494g.

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Buncel, Erwin, Ruby Nagelkerke, and Gregory RJ Thatcher. "Alkali metal ion catalysis in nucleophilic displacement by ethoxide ion on p-nitrophenyl phenylphosphonate: Evidence for multiple metal ion catalysis." Canadian Journal of Chemistry 81, no. 1 (January 1, 2003): 53–63. http://dx.doi.org/10.1139/v02-202.

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In continuation of our studies of alkali metal ion catalysis and inhibition at carbon, phosphorus, and sulfur centers, the role of alkali metal ions in nucleophilic displacement reactions of p-nitrophenyl phenylphosphonate (PNPP) has been examined. All alkali metal ions studied acted as catalysts. Alkali metal ions added as inert salts increased the rate while decreased rate resulted on M+ complexation with 18-crown-6 ether. Kinetic analysis indicated the interaction of possibly three potassium ions, four sodium ions, and five lithium ions in the transition state of the reactions of ethoxide with PNPP. Pre-association of the anionic substrate with two metals ions in the ground state gave the best fit to the experimental data of the sodium system. Thus, the study gives evidence of the role of several metal ions in nucleophilic displacement reactions of ethoxide with anionic PNPP, both in the ground state and in the transition state. Molecular modeling of the anionic transition state implies that the size of the monovalent cation and the steric requirement of the pentacoordinate transition state are the primary limitations on the number of cations that can be brought to bear to stabilize the transition state and catalyze nucleophilic substitution at phosphorus. The bearing of the present work on metal ion catalysis in enzyme systems is discussed, in particular enzymes that catalyze phosphoryl transfer, which often employ multiple metal ions. Our results, both kinetic and modeling, reveal the importance of electrostatic stabilization of the transition state for phosphoryl transfer that may be effected by multiple cations, either monovalent metal ions or amino acid residues. The more such cations can be brought into contact with the anionic transition state, the greater the catalysis observed.Key words: alkali metal ion catalysis, nucleophilic displacement at phosphorus, multiple metal ion catalysis, phosphoryl transfer.

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Abu Hasan, Rumaisa, Muhamad Saiful Bahri Yusoff, Tong Boon Tang, Yasir Hafeez, Mazlina Che Mustafa, Masayu Dzainudin, Juppri Bacotang, Ubaid M. Al-Saggaf, and Syed Saad Azhar Ali. "Resilience-Building for Mental Health among Early Childhood Educators: A Systematic Review and Pilot-Study towards an EEG-VR Resilience Building Intervention." International Journal of Environmental Research and Public Health 19, no. 7 (April 6, 2022): 4413. http://dx.doi.org/10.3390/ijerph19074413.

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Resilience is a key factor that reflects a teacher’s ability to utilize their emotional resources and working skills to provide high-quality teaching to children. Resilience-building interventions aim to promote positive psychological functioning and well-being. However, there is lack of evidence on whether these interventions improve the well-being or mental health of teachers in early childhood education (ECE) settings. This review examined the overall effectiveness of resilience-building interventions conducted on teachers working in the ECE field. A systematic approach is used to identify relevant studies that focus on resilience-building in countering work stress among early childhood educators. Findings from this review observed a preference of group approaches and varying durations of interventions. This review highlights the challenges of the group approach which can lead to lengthy interventions and attrition amongst participants. In addition to the concerns regarding response bias from self-report questionnaires, there is also a lack of physiological measures used to evaluate effects on mental health. The large efforts by 11 studies to integrate multiple centres into their intervention and the centre-based assessment performed by four studies highlight the need for a centre-focused approach to build resilience among teachers from various ECE centres. A pilot study is conducted to evaluate the feasibility of an integrated electroencephalography–virtual reality (EEG-VR) approach in building resilience in teachers, where the frontal brain activity can be monitored during a virtual classroom task. Overall, the findings of this review propose the integration of physiological measures to monitor changes in mental health throughout the resilience-building intervention and the use of VR as a tool to design a unique virtual environment.

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Wan, Ho Chuen, Jing-Xuan Zhang, Chung Sum Leung, Fu Kit Sheong, and Zhenyang Lin. "Inter-ligand delocalisations in transition metal complexes containing multiple non-innocent ligands." Dalton Transactions 48, no. 39 (2019): 14801–7. http://dx.doi.org/10.1039/c9dt02806d.

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Gamache, Mira T., Thomas Auvray, Dirk G. Kurth, and Garry S. Hanan. "Dinuclear 2,4-di(pyridin-2-yl)-pyrimidine based ruthenium photosensitizers for hydrogen photo-evolution under red light." Dalton Transactions 50, no. 45 (2021): 16528–38. http://dx.doi.org/10.1039/d1dt00868d.

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Yang, Xiu-Li, Ming-Hua Xie, Chao Zou, Fei-Fei Sun, and Chuan-De Wu. "A series of metal–organic coordination polymers containing multiple chiral centers." CrystEngComm 13, no. 5 (2011): 1570–79. http://dx.doi.org/10.1039/c0ce00633e.

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Gul, Sheraz, Jia Wei Desmond Ng, Roberto Alonso-Mori, Jan Kern, Dimosthenis Sokaras, Eitan Anzenberg, Benedikt Lassalle-Kaiser, et al. "Simultaneous detection of electronic structure changes from two elements of a bifunctional catalyst using wavelength-dispersive X-ray emission spectroscopy and in situ electrochemistry." Physical Chemistry Chemical Physics 17, no. 14 (2015): 8901–12. http://dx.doi.org/10.1039/c5cp01023c.

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Aulsebrook, Stephanie Jane. "Understanding the role of metal within the Late Bronze Age community at Mycenae: challenges and potential approaches." Polish Archaeology in the Mediterranean, no. 29/2 (December 31, 2020): 247–70. http://dx.doi.org/10.31338/uw.2083-537x.pam29.2.10.

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Metal has been widely argued as playing a decisive role in the development of Mycenae, which became one of the foremost centers on the Late Bronze Age Greek mainland. Yet, little is understood as to how metals were integrated into the lives of the inhabitants. Most scholarship has concentrated on the relationship between the ruling class and metal artifacts, drawing much of the evidence from the Linear B archives and top-down models of trade, society and internal redistribution that are increasingly considered untenable within the study of other aspects of Mycenaean life. This paper presents a new project, which uses a practice-orientated approach based around object biographies to study the use of metal across the entire social spectrum of the Late Bronze Age community at Mycenae (approximately 1700–1050 BC). The benefits of such an approach are discussed through a case study that examines the unexpected absence of gold vessels from the Palatial period archaeological record from the perspective of social practice and demonstrates how the holistic use of evidence from multiple sources can help overcome the difficulties inherent in the study of the use of metal in past societies.

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Wei, Qinghua, Xiaochu Ma, Jianghui Chen, Li Niu, Xi Yang, Fei Xia, and Shunying Liu. "A triple-functionalised metal centre-catalyzed enantioselective multicomponent reaction." Organic Chemistry Frontiers 5, no. 19 (2018): 2799–804. http://dx.doi.org/10.1039/c8qo00703a.

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A model of a triple-functionalised metal centre for the discovery of unprecedented enantioselective reactions was exquisitely developed by using a Rh^I/(DHQ)₂PHAL catalyst system via multiple coordination interactions with different ligands and substrates.

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Froud, Joseph, Freddie St John, Mark Willis, Valerie Anderson, Emeka Uzochukwu, Ray Wynford Thomas, Katharine Harding, Emma Tallantyre, and Neil Robertson. "120 UK multiple sclerosis registries project: disease modifying treatment durability." Journal of Neurology, Neurosurgery & Psychiatry 93, no. 9 (August 12, 2022): e2.73. http://dx.doi.org/10.1136/jnnp-2022-abn2.164.

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BackgroundReal-world, long-term adherence and effectiveness data is vital to complement our under- standing of therapies, which is often based on short-term clinical trials. Here we explored disease modifying therapy (DMT) durability in a UK-wide cohort of people with Multiple Sclerosis (pwMS).MethodsIn this cohort study, which included 4,415 pwMS from 10 UK MS centres, 6,960 DMT prescrip- tions were included in the analysis (mean 1.7, range 1-6 per patient). Prescriptions without accurate start dates were excluded (n=90). Kaplan-Meier survival analysis was used to model DMT persistence (days from prescription start to stop), which was used to calculate 2, 5 and 10-year durability (% of prescrip- tions continuing).ResultsTwo-year durability was highest for immune reconstitution therapies cladribine (98%), ocrelizumab (96%), and alemtuzumab (95%). Oral therapies fingolimod (74%) and dimethyl fumarate (73%), and intravenous natalizumab (78%) shared similar durability. Injectable therapies glatiramer acetate (51%) and interferon (55%), had lowest durability. Potential confounding factors include variable date of DMT licensing, change in DMT algorithms over time and increasing DMT options.ConclusionThis multi-centre study has revealed highly variable durability between DMTs over time, which may impact real-world effectiveness. These results may inform DMT clinical decision-making and improve outcomes for pwMS.

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Gavrichenko, Nikolay E., and Pavel V. Petrov. "ANALYSIS AND CLASSIFICATION OF MANUFACTURING CENTERS FOCUSED ON MECHANICAL PART OF OPTICAL DEVICES." Interexpo GEO-Siberia 6, no. 1 (July 8, 2020): 91–98. http://dx.doi.org/10.33764/2618-981x-2020-6-1-91-98.

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The article deals with the concept of flexible and dynamic classification of metal-cutting machines of the "turning processing center" (TPC) type for the production of complex metal parts of optical devices by cutting. It is intended to create specialized databases with a formalized description of the structural elements of the TPC and automatically perform multiple classifications, relying on various factors. The comprehensive analysis of machine-tool companies is made; the generalized structure of structural elements and parameters of modern TPC is defined.

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Von Werner, Konrad. "Reactions of perfluoroalkyl iodides with CC-multiple bonds induced by transition metal centers." Journal of Fluorine Chemistry 28, no. 2 (June 1985): 229–33. http://dx.doi.org/10.1016/s0022-1139(00)81145-8.

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Matthews, P. M. "Primary progressive multiple sclerosis takes centre stage." Journal of Neurology, Neurosurgery & Psychiatry 75, no. 9 (September 1, 2004): 1232–33. http://dx.doi.org/10.1136/jnnp.2004.044263.

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Wang, Hechen, Xiaolei Chen, Yali Wang, Lu Wang, Zhangzhao Gao, Haihong Hu, Lushan Yu, Su Zeng, and Yu Kang. "Probing Fast Enantio-Recognition of Drugs with Multiple Chiral Centers by Electrospray-Tandem Mass Spectrometry and Its Mechanism." Applied Sciences 12, no. 20 (October 14, 2022): 10353. http://dx.doi.org/10.3390/app122010353.

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Chiral drugs are very complex substances since individual enantiomers may differ in pharmacological and toxic effects, making it necessary to analyze enantiomers separately. In this study, we investigated the chiral differentiation of two ezetimibe enantiomers (i.e., SRS-EZM and RSR-EZM) and their mechanisms in complex with β-cyclodextrins (CDs) and metal ions as the auxiliary ligands. For this purpose, two complementary approaches have been employed: electrospray-tandem mass spectrometry (ESI-MS/MS) with collision induced dissociation (CID) and molecular modeling methods, including density functional theory (DFT) calculations and molecular dynamics (MD) simulations. The results showed a good agreement between experimental and theoretical data. It was demonstrated that SRS-EZM can be easily distinguished from RSR-EZM by applying CID in ESI-MS/MS. SRS-EZM is likely to form a more stable complex with β-CD and metal ions, and thus the [SRS-EZM]-Cu-[β-CD] cluster is more energetically difficult to separate from the SRS-EZM molecule compared with RSR-EZM. Such a difference may be attributed to the interactions between the drug molecule and the metal ion, as well as the cavity shape changes of the β-CDs upon complexation with molecular guests. Therefore, enantiomers in chiral drug can be recognized as ternary complexes of metal-analyte-β-CD by ESI-MS/MS with CID.

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Frank, Rowena, Lisa Fawcett, and Brett Emmerson. "Development of Australia's First Psychiatric Emergency Centre." Australasian Psychiatry 13, no. 3 (September 2005): 266–72. http://dx.doi.org/10.1080/j.1440-1665.2005.02200.x.

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Objectives: To describe the development of the first Australian psychiatric emergency centre co-located with the Emergency Department at the Royal Brisbane and Women's Hospital. This paper covers the current operational model, significant partnerships and benefits of this service, which assesses and treats over 7200 presentations per year. Conclusions: The co-location of the Psychiatric Emergency Centre and Emergency Department has created a unique model of service delivery and effective working relationships between the two services. The model improves clinical care providing multiple benefits for patients and the Emergency Department by means of direct access to specialized mental health staff, early mental health responsibility for patients and reduced access block.

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Ornatsky, Olga, Bedilu Allo, Nafiseh Talaei, Alexandre Bouzekri, and Vladimir Baranov. "Topology of multiple antigen expression in tonsillar lymphoid follicles and stroma analyzed by imaging mass cytometry." Journal of Immunology 198, no. 1_Supplement (May 1, 2017): 81.8. http://dx.doi.org/10.4049/jimmunol.198.supp.81.8.

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Abstract Investigation of co-distribution of 35 biomarkers simultaneously (major cell type and immune-oncology, stromal and tissue architecture markers, as well as cell proliferation and nuclear markers) in normal lymphoid sections using Imaging Mass Cytometry (Qing et al, Cytometry: Part A, 2017) is presented. Tonsil tissue revealed primary lymph follicles as dense clusters of lymphocytes expressing B-cell markers, surrounded by CD3, CD4, and CD8 T-cells. Secondary lymph follicles could be distinguished by proliferating B-cells with high Ki-67 expression. Strong expression of Bcl-6 was detected in germinal-center B-cells. Tonsillar FoxP3 CD8 T-cells exhibit a Treg phenotype with high CTLA-4 and CD45RO. CD68+ mac/mono were found in germinal centers and rarely in stroma. Squamous epithelium of crypts was beta-catenin positive and infiltrated by PD-L1+ T-cells, while PD-1+ cells were also found within the follicle centers. Images acquired on the Hyperion™ Imaging System (Fluidigm Inc.) were compared to immunofluorescence (IF) of sequential sections stained with the same antibodies (Ab) conjugated to fluorophores (FL). For direct comparison of IF and IMC, dual tagged Abs were created by attaching a metal tag first (Maxpar®, Fluidigm Inc.), then conjugating to FL using click chemistry. CD3 and CD19 were labeled with metals and FL, and tested in combination with the full panel on 8 μm frozen tonsil sections. CD3+ and CD19+ lymphs were identified by IF first, followed by IMC analysis. Results show that IMC is comparable to IF images and allows identification, characterization and localization of cell populations and tissue architecture in the absence of autofluorescence, photobleaching, with low background for acquisition of up to 50 targets.

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Gao, Xiaonan, Ai-Yun Fu, Bo Liu, Jun-cheng Jin, Long-Tao Dou, and Li-Xia Chen. "Unique Topology Analysis by ToposPro for a Metal–Organic Framework with Multiple Coordination Centers." Inorganic Chemistry 58, no. 5 (February 15, 2019): 3099–106. http://dx.doi.org/10.1021/acs.inorgchem.8b03104.

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Owen, Natalie, Leanne Dew, Stuart Logan, Simon Denegri, and Lucy C. Chappell. "Research policy for people with multiple long-term conditions and their carers." Journal of Multimorbidity and Comorbidity 12 (January 2022): 263355652211044. http://dx.doi.org/10.1177/26335565221104407.

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People with multiple long-term conditions (MLTC) are a growing population, not only in the United Kingdom but internationally. Health and care systems need to adapt to rise to this challenge. Policymakers need to better understand how medical education and training, and service configuration and delivery should change to meet the needs of people with MLTC and their carers. A series of workshops with people with MLTC and carers across the life-course identified areas of unmet need including the impact of stigma; poorly coordinated care designed around single conditions; inadequate communication and consultations that focus on clinical outcomes rather than patient-oriented goals and imperfectly integrate mental and physical wellbeing. Research which embeds the patient voice at its centre, from inception to implementation, can provide the evidence to drive the change to patient-centred, coordinated care. This should not only improve the lives of people living with MLTC and their carers but also create a health and care system which is more effective and efficient. The challenge of MLTC needs to be bought to the fore and it will require joint effort by policymakers, practitioners, systems leaders, educators, the third sector and those living with MLTC to design a health and care system from the perspective of patients and carers, and provide practitioners with the skills and tools needed to provide the highest quality care.

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Gallenkamp, Charlotte, Lingmei Ni, Vera Krewald, and Ulrike I. Kramm. "Oxygen Reduction Reaction on Fe-N-C Catalysts: A Computational Spectroscopy Study." ECS Meeting Abstracts MA2022-02, no. 42 (October 9, 2022): 1595. http://dx.doi.org/10.1149/ma2022-02421595mtgabs.

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The oxygen reduction reaction (ORR) plays an important role in proton exchange fuel cells (PEFCs). In PEFCs, ORR is the cathodic half-cell reaction complementary to the oxidation of the fuel, but since ORR has slow kinetics, it requires high amounts of catalyst. State-of-the-art ORR catalysts are based on the expensive metal platinum. Even though the amount of platinum needed for ORR in PEFCs has been reduced significantly over the last decade, it is still the major contributor to the cost of PEFCs, thus hindering the commercialization and accessibility of this technology.[1] Iron and nitrogen doped carbon (Fe-N-C) catalysts have gained a lot of research attention due to their high ORR activity, which makes them potential substitutes for platinum-based catalysts. In Fe-N-C catalysts, iron is thought to be atomically dispersed as pseudo-molecular active centres with four- or fivefold nitrogen coordination spheres which are embedded in graphene layers. Since Fe-N-C catalysts are typically prepared via pyrolysis, they have a highly amorphous structure and can contain multiple iron phases, which makes them difficult to characterize structurally and spectroscopically. Consequently, there is still a scientific debate on the exact nature of the active site, in terms of iron spin and oxidation states and its precise coordination environment.[2-4] Fe-57 Mössbauer spectroscopy can provide direct insights on iron spin and oxidation states and is used successfully to characterise the amorphous Fe-N-C catalysts. Until recently, the interpretation of Mössbauer spectra was limited to comparisons with small reference complexes which lack the extended π-systems of Fe-N-C catalysts.[2] Since synthesis of such extended π-systems as references is difficult, we have developed a library of computational models that encompasses different structural motifs and electronic structures. With increasing use of in situ and operando experiments on Fe-N-C catalysts, the interest in computational models for the interpretation of experimental Mössbauer spectra has grown.[4-6] In this contribution, we present our density functional theory results for different molecular Fe-N-C models with extended π-systems and discuss their electronic structures and spectroscopic properties. [1] L. Osmieri, et al. Current Opinion in Electrochemistry 2021, 25, 100627. [2] U. I. Kramm, et al. Advanced Materials 2019, 31, 1805623. [3] S. Wagner, et al. Angewandte Chemie International Edition 2019, 58, 10486. [4] L. Ni, C. Gallenkamp, et al. Advanced Energy & Sustainability Research 2021, 2, 2000064. [5] J. Li, et al. Nature Catalysis, 2021, 4, 10. [6] X. Liu, et al. Chem 2020, 6, 3440.

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Jakovljevic, Ksenija, Aida Bani, Dolja Pavlova, Maria Konstantinou, Panayiotis Dimitrakopoulos, Dimitris Kyrkas, Roger Reeves, et al. "Hyperaccumulator plant discoveries in the Balkans: Accumulation, distribution, and practical applications." Botanica Serbica 46, no. 2 (2022): 161–78. http://dx.doi.org/10.2298/botserb2202161j.

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Hyperaccumulator plants are able to tolerate extremely high concentrations of metals/metalloids in the soil in which they grow and to accumulate high concentrations in their shoots. To date, a total of 31 hyperaccumulator plant species have been identified in the Balkans, the centre of diversity and speciation in the European flora which is particularly rich in ultramafic areas. A further 8 species have yet to be confirmed through additional studies. Most of the 31 hyperaccumulator taxa (13 taxa or 41.9%) are species of the genus Odontarrhena, all hyperaccumulating Ni, but concentrations of this element above the hyperaccumulation threshold were also found in the genera Bornmuellera and Noccaea (all Brassicaceae), Orobanche (Orobanchaceae), Centaurea (Asteraceae) and Viola (Violaceae). The existence of hyperaccumulators of Tl and Zn is of particular interest because very few species worldwide hyperaccumulate these elements. Multiple metal hyperaccumulation was found in Noccaea kovatsii, as the hyperaccumulation of Zn was found in this species in addition to Ni, the primary accumulated element. Metal hyperaccumulation is discussed in terms of phylogenetic relationships and species distributions, with special attention to their systematics, the detection and recognition of new hyperaccumulating species and the possibilities for their future practical applications in phytotechnologies.

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Kotecki, Demian J. "Some pitfalls in welding of duplex stainless steels." Soldagem & Inspeção 15, no. 4 (December 2010): 336–43. http://dx.doi.org/10.1590/s0104-92242010000400011.

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Duplex stainless steels (DSS, including super duplex stainless steels {SDSS}) have proven to be very useful engineering materials, albeit with somewhat different welding requirements than those of the more familiar austenitic stainless steels. Despite a generally good track record in welding of duplex stainless steels, certain pitfalls have been encountered with enough frequency that they deserve review. Inappropriate base metal specification often leads to unsuitable heat affected zone (HAZ) properties. Autogenous fusion zones are also of concern. This issue centers around nitrogen limits. The most frequently encountered is applying the UNS S31803 composition for 2205 DSS, instead of the S32205 composition. Inappropriate welding heat input arises most frequently with SDSS. While 0.5 to 1.5 kJ/mm is a normal heat input recommendation for SDSS, either a root pass or many small beads towards the low end of this heat input range tends to result in precipitation and/or secondary austenite formation in weld metal subjected to repeated thermal cycles from multiple weld passes. Inappropriate PWHT occurs when the enhanced nickel filler metals (typically 9% Ni) are used. DSS are not normally given PWHT, but extensive forming of heads, for example, or repair welding of castings, may require a postweld anneal. Specifications such as ASTM A790 and A890 call for annealing at 1040ºC minimum, and the fabricator tends to use temperatures close to that minimum. However, the enhanced nickel filler metals require higher temperatures to dissolve sigma phase that forms during heating to the annealing temperature.

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Sriram, T. G., C. R. Chandrashekar, Mohan K. Isaac, and R. Srinivasa Murthy. "Training primary care medical officers in mental health care: assessment using a structured clinical examination." Psychiatric Bulletin 14, no. 8 (August 1990): 481–82. http://dx.doi.org/10.1192/pb.14.8.481.

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Mental health problems in primary care settings have received wider attention in recent years (Wilkinson, 1985). In India, the National Mental Health Programme (NMHP) was formulated with the purpose of promoting mental health care through primary health care (National Mental Health Programme, 1982). As part of the implementation of NMHP, training programmes for medical officers and health workers have been initiated in a number of centres in the country (National Mental Health Programme for India, Progress Report, 1988). At the National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, a monthly training programme for doctors and health workers of primary health centres has been carried out since 1982. In order to evaluate the gain in knowledge and clinical skills, a multiple-choice questionnaire and case vignettes have been standardised (Sriram et al, in press). The doctors are also evaluated through a structured clinical examination which is carried out on the last training day. The focus of the present report is to evaluate the clinical skills of medical officers using the structured clinical examination.

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Cohen, L. Adelyn, and Christine A. Limbers. "Mental health and parenting stress in mothers of children with diabetes treated in a patient-centred medical home." Family Practice 36, no. 4 (November 16, 2018): 486–92. http://dx.doi.org/10.1093/fampra/cmy110.

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Abstract Background Mothers of children with diabetes are at-risk for experiencing parenting stress and diminished mental/emotional health. To the best of our knowledge, no studies to date have examined whether there are differences in these outcomes between mothers whose diabetic child is managed in a patient-centred medical home or not. Objective The objective of the present study was to assess whether there were differences in mental health and parenting stress among mothers whose diabetic child was managed in a patient-centred medical home or not. Methods Two hundred fifty-three mothers of children with diabetes (mean age = 12.50 years; SD = 3.90) from the 2011–2012 National Survey of Children’s Health were included in this study. Hierarchical multiple regression was conducted to determine the amount of variance that having a patient-centred medical home contributed to maternal emotional/mental health and parenting stress. Results After controlling for child sex, age, race/ethnicity and family poverty level, patient-centred medical home status was associated with better mental health for mothers and less parenting stress. Effective care coordination was the only subcomponent of the patient-centred medical home that significantly contributed to the variance in mother’s mental/emotional health and parenting stress. Conclusions Receiving care in a patient-centred medical home, particularly the care coordination component, may mitigate some of the negative maternal effects of managing a child’s diabetes.

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Dubois, B. D. "Interferon beta in multiple sclerosis: experience in a British specialist multiple sclerosis centre." Journal of Neurology, Neurosurgery & Psychiatry 74, no. 7 (July 1, 2003): 946–49. http://dx.doi.org/10.1136/jnnp.74.7.946.

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Saraev, Yu N., V. Р. Bezborodov, М. V. Perovskaya, and V. М. Semenchuk. "Modification of steel surface layer by electroslag surfacing using compounds with high melting point." Izvestiya. Ferrous Metallurgy 64, no. 9 (October 9, 2021): 679–84. http://dx.doi.org/10.17073/0368-0797-2021-9-679-684.

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The authors have studied the effect of alloying on the structure, microhardness and abrasive wear resistance of electroslag surfacing layers on low-alloy structural steel 09G2S. For modification, mixtures of Si3 N4 + FeSi2 + Si powders obtained in the Department of Structural Macrokinetics of the Tomsk Scientific Centre SB RAS by the method of SHS synthesis, as well as powder compositions based on TiC, were used. A molten electrode was made of low-alloy steel St3, on which modifying compositions Si3 N4 + FeSi2 + Si were poured out, in the first case, and modifying compositions Si3 N4 + FeSi2 + Si, located below, in the second case. Metallography and X-ray microanalysis methods were used to determine the structure and to analyze the composition of the deposited layers, heat-affected zone (HAZ) and the base metal, on the basis of which assumptions were made about the nature of the formation of coating properties – hardness and wear resistance. It is shown that the main influence on the wear resistance is exerted by structure of the surfacing metal. There is a positive effect of modifying coatings by alloying materials with the alloys Si3 N4 + FeSi2 + Si + St3 and TiC + St3. In the molten layer, many new crystallization centers are released in the form of dispersed TiC particles. Dispersed TiC particles with a high melting point (3180 °C) are the first to fall out of the melt and not only serve as multiple crystallization centers, but also prevent the growth of austenitic grains, which ensures the formation of dispersed structure. The coatings contain TiC carbide particles, as well as inclusions of other phases. At the same time, an increase in hardness of the deposited layer containing titanium carbide inclusions is observed in direction of the boundary with the base. Wear resistance of the layer increases when a TiC-based coating is formed. The obtained data can be used to create deposited layers on the metal surface with high resistance against abrasive wear.

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Murphy, Eamonn, Yuanchao Liu, Ivana Matanovic, Alvin Ly, Ying Huang, Shengyuan Guo, Hanson Wang, Iryna V. Zenyuk, Erik D. Spoerke, and Plamen Atanassov. "The Role of Atomically Dispersed Transition Metal Centers for the Electrochemical Nitrate Reduction Reaction Towards Ammonia Synthesis." ECS Meeting Abstracts MA2022-01, no. 40 (July 7, 2022): 1806. http://dx.doi.org/10.1149/ma2022-01401806mtgabs.

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The electrochemical reduction of oxidized nitrogen species, nitrate (NO3 -) and nitrite (NO2 -), both of which are environmental pollutants, to benign nitrogen gas (N2) has been extensively researched for water remediation applications. Recently, a large research focus has shifted to reducing these oxidized nitrogen species to ammonia (NH3).1 In this way, a dual benefit is achieved by eliminating the environmentally hazardous nitrates, while also creating a value-added product, ammonia. Moreover, the nitrate reduction reaction (NO3RR) can aid in closing the nitrogen cycle, by reforming nitrates introduced into the environment through nitrate-based fertilizers originating from the Haber-Bosch process, back into NH3, in a carbon neutral fashion. The NO3RR is a complex, 8e-, 9H+ transfer process with multiple possible intermediate species (NO2 -, NO, N2O, N2H4, NH2OH, NH3) and rate limiting steps. The NO3RR mechanism and its activity descriptors over various metals is not fully understood, and this is especially true over atomically dispersed sites, where less than a handful of studies exist.2,3 Our previous work found that atomically dispersed nitrogen coordinated Fe-N4 and Mo-N4 sites displayed distinct associative adsorption and dissociative adsorption of the nitrate molecule in the NO3RR pathways, respectively. Specifically, Fe-N4 sites adsorb and reduce NO3 - into NH3through an 8e- pathway on the surface, while Mo-N4 sites dissociate NO3 - and release NO2 - into the bulk electrolyte. These active sites were then integrated into a single bi-metallic catalyst (FeMo-N-C), creating a catalytic cascade yielding a significantly improved yield rate and Faradaic efficiency for NH3.4 In this talk, building on our previous work, we will present a series of transition metal atomically dispersed nitrogen doped carbon (M-N-C) electrocatalysts (M = Mn, Fe, Co, Ni, Cu...) for the systematic investigation of NO3RR activities over the different metal centers. In this work we leverage physical (ICP-MS, gas physisorption), electrochemical (e.g., NO3RR) and computational (DFT) characterization to create a set of NO3RR activity descriptors. A detailed set of activity descriptors can aid in the selection of atomically dispersed metals for creating efficient reaction cascades to synergize favorable reaction pathways. Figure 1

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Remya, Premaja R., and Cherumuttathu H. Suresh. "Planar tetracoordinate carbon in tungstenacyclobutadiene from alkyne metathesis and expanded structures." Dalton Transactions 45, no. 4 (2016): 1769–78. http://dx.doi.org/10.1039/c5dt03922c.

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Establishing the C_β of tungstenacyclobutadiene (WCBD) as a _ptC center paves the way for a new strategy to make novel materials containing multiple _ptC centers. The 1-, 2- and 3-dimensional expansion of the WCBD motifs provides access to _ptC-incorporated new metal–organic frameworks.

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Yan, Bing. "Lanthanide-Functionalized Metal–Organic Framework Hybrid Systems To Create Multiple Luminescent Centers for Chemical Sensing." Accounts of Chemical Research 50, no. 11 (October 6, 2017): 2789–98. http://dx.doi.org/10.1021/acs.accounts.7b00387.

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Lu, Xiu Lian, Thomas D. McGrath, and F. Gordon A. Stone. "Synthesis and Reactivity of 10- and 12-Vertex Cobalt−Monocarborane Anions Containing Multiple Metal Centers." Organometallics 25, no. 10 (May 2006): 2590–98. http://dx.doi.org/10.1021/om060123d.

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Smith, Stephanie L., Beatha Nyirandagijimana, Janvier Hakizimana, Roger P. Levy, Robert Bienvenu, Anathalie Uwamwezi, Octavien Hakizimfura, et al. "Evaluating the delivery of Problem Management Plus in primary care settings in rural Rwanda: a study protocol using a pragmatic randomised hybrid type 1 effectiveness-implementation design." BMJ Open 11, no. 12 (December 2021): e054630. http://dx.doi.org/10.1136/bmjopen-2021-054630.

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IntroductionEvidence-based low-intensity psychological interventions such as Problem Management Plus (PM+) have the potential to expand treatment access for depression and anxiety, yet these interventions are not yet effectively implemented in rural, public health systems in resource-limited settings. In 2017, Partners In Health adapted PM+ for delivery by primary care nurses in rural Rwanda and began integrating PM+ into health centres in collaboration with the Rwandan Ministry of Health, using established implementation strategies for mental health integration into primary care (Mentoring and Enhanced Supervision at Health Centers for Mental Health (MESH MH)). A gap in the evidence regarding whether low-intensity psychological interventions can be successfully integrated into real-world primary care settings and improve outcomes for common mental disorders remains. In this study, we will rigorously evaluate the delivery of PM+ by primary care nurses, supported by MESH MH, as it is scaled across one rural district in Rwanda.Methods and analysisWe will conduct a hybrid type 1 effectiveness-implementation study to test the clinical outcomes of routinely delivered PM+ and to describe the implementation of PM+ at health centres. To study the clinical effectiveness of PM+, we will use a pragmatic, randomised multiple baseline design to determine whether participants experience improvement in depression symptoms (measured by the Patient Health Questionnaire-9) and functioning (measured by the WHO-Disability Assessment Scale Brief 2.0) after receiving PM+. We will employ quantitative and qualitative methods to describe and evaluate PM+ implementation outcomes using the Reach, Effectiveness, Adoption, Implementation and Maintenance framework, using routinely collected programme data and semistructured interviews.Ethics and disseminationThis evaluation was approved by the Rwanda National Ethics Committee (Protocol #196/RNEC/2019) and deemed exempt by the Harvard University Institutional Review Board. The results from this evaluation will be useful for health systems planners and policy-makers working to translate the evidence base for low-intensity psychological interventions into practice.

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Seghatoleslam, T., H. Habil, O. Rezaee, S. Sadr, and R. Emamhadi. "Is suicide predictable? A classification of predictive factors in Iranian women who had multiple suicide attempts." European Psychiatry 26, S2 (March 2011): 1642. http://dx.doi.org/10.1016/s0924-9338(11)73346-6.

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BackgroundThe current study aims to test the hypothesis: Is suicide predictable? And try to classify the predictive factors in multiple suicide attempts.MethodA cross-sectional study was administered to 223 multiple attempters, women who came to a medical poison centre after a suicide attempt. The participants were young, poor, and single. A Regression Logistic Test was used to classify the predictive factors of suicide.ResultsWomen who had multiple suicide attempts exhibited a significant tendency to attempt suicide again. They had a history for more than two years of multiple suicide attempts, from three to as many as 18 times, plus mental illnesses such as depression and substance abuse. They also had a positive history of mental illnesses.ConclusionResults indicate that contributing factors for another suicide attempt include previous suicide attempts, mental illness (depression), or a positive history of mental illnesses in the family affecting them at a young age, and substance abuse.

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Ghadiri-Sani, Mona, Josh Foulton, and Martin Wilson. "PO126 Alemtuzumab in multiple sclerosis – the walton centre experience." Journal of Neurology, Neurosurgery & Psychiatry 88, Suppl 1 (December 2017): A45.2—A45. http://dx.doi.org/10.1136/jnnp-2017-abn.156.

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Mastrobuono-Battisti, Alessandra, Hagai B. Perets, Alessia Gualandris, Nadine Neumayer, and Anna C. Sippel. "Star formation at the Galactic Centre: coevolution of multiple young stellar discs." Monthly Notices of the Royal Astronomical Society 490, no. 4 (October 24, 2019): 5820–31. http://dx.doi.org/10.1093/mnras/stz3004.

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ABSTRACT Studies of the Galactic Centre suggest that in situ star formation may have given rise to the observed stellar population near the central supermassive black hole (SMBH). Direct evidence for a recent starburst is provided by the currently observed young stellar disc (2–7 Myr) in the central 0.5 pc of the Galaxy. This result suggests that star formation in galactic nuclei may occur close to the SMBH and produce initially flattened stellar discs. Here, we explore the possible build-up and evolution of nuclear stellar clusters near SMBHs through in situ star formation producing stellar discs similar to those observed in the Galactic Centre and other nuclei. We use N-body simulations to model the evolution of multiple young stellar discs and explore the potential observable signatures imprinted by such processes. Each of the five simulated discs is evolved for 100 Myr before the next one is introduced in the system. We find that populations born at different epochs show different morphologies and kinematics. Older and presumably more metal-poor populations are more relaxed and extended, while younger populations show a larger amount of rotation and flattening. We conclude that star formation in central discs can reproduce the observed properties of multiple stellar populations in galactic nuclei differing in age, metallicity, and kinematic properties.

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Myo, Theigi, Seo Ah Hong, Bang-On Thepthien, and Nate Hongkrailert. "Prevalence and Factors Associated with Postpartum Depression in Primary Healthcare Centres in Yangon, Myanmar." Malaysian Journal of Medical Sciences 28, no. 4 (August 26, 2021): 71–86. http://dx.doi.org/10.21315/mjms2021.28.4.8.

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Background: Postpartum depression (PPD) can have serious consequences on both the mother and infant. Despite the higher prevalence, there are limited numbers of studies on PPD in low- and middle-income countries, like Myanmar. This study aimed to explore the prevalence and associated factors of PPD in primary healthcare settings in Myanmar. Methods: This cross-sectional online study was conducted with 220 mothers under 6 months postpartum in April–May 2020 and who registered in public health centres in Kungyangone Township, Yangon, Myanmar. The postpartum depression was measured with the Edinburgh postpartum depression scale (EPDS, ≥ 13 scores). Independent variables included sociodemographic factors, obstetric and infant factors, psychosocial factors (social support and social media usage), health services utilisation and accessibility factors. Chi-square tests and multiple logistic regression were performed. Results: Overall prevalence of depressive symptoms in 220 women under 6 months postpartum was 31.8% (95% confidence interval [CI]: 25.9, 37.3). In multiple logistic regression, unplanned pregnancy (adjusted odds ratio [AOR]: 2.946), less than four times antenatal care (ANC) visits (AOR: 2.518), travel time more than 1 h to reach health centres (AOR: 3.068) and birth interval more than 5 years (AOR: 4.594) were more likely to be associated with PPD, while preterm delivery (AOR: 0.091) was inversely associated. Conclusion: This study showed the relatively high prevalence of PPD and the strong association with preterm delivery, pregnancy intention, breastfeeding status, birth interval as well as frequency of ANC received and travel time to health centre. It may suggest that maternal mental health services should be integrated with existing maternal and child health (MCH) services for early detection and prevention of depression symptoms with promotion of MCH services utilisation and improved accessibility among mothers in primary healthcare setting.

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Frau, I., S. R. Wylie, P. Byrne, J. D. Cullen, O. Korostynska, and A. Mason. "Functionalised microwave sensors for real-time monitoring of copper and zinc concentration in mining-impacted water." International Journal of Environmental Science and Technology 17, no. 4 (November 16, 2019): 1861–76. http://dx.doi.org/10.1007/s13762-019-02588-w.

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AbstractMicrowave spectroscopy has been identified as a novel and inexpensive method for the monitoring of water pollutants. Integrating microwave sensors with developed coatings is a novel strategy to make the sensing system more specific for a target contaminant. This study describes the determination of copper and zinc concentration in water in both laboratory-prepared and acquired mine water samples from two abandoned mining areas in Wales, UK. Uncoated sensors immersed in samples spiked with 1.25 mg/L concentrations of copper and zinc, using the standard addition method, were able to quantify the concentration at 0.44 GHz with a strong linear correlation (R2 = 0.99) for the reflection coefficient magnitude (|S11|). Functionalised microwave sensors with l-cysteine, chitosan and bismuth zinc cobalt oxide-based coatings have shown improvement in the sensing performance. Specifically, the linear correlation at 0.91–1.00 GHz between |S11| and a polluted water sample spiked with Cu showed a higher (R2 = 0.98), sensitivity (1.65 ΔdB/mg/L) and quality factor (135) compared with uncoated sensors (R2 = 0.88, sensitivity of 0.82 ΔdB/mg/L and Q-factor 30.7). A Lorentzian peak fitting function was applied for performing advanced multiple peak analysis and identifying the changes in the resonant frequency peaks which are related to the change in metal ion content. This novel sensor platform offers the possibility of in situ monitoring of toxic metal concentrations in mining-impacted water, and multiple peak features, such as area, full width half maximum, centre and height of the peaks, have the possibility to offer higher specificity for similar toxic metals, as between copper and zinc ions.

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Journal articles on the topic 'Multiple metal centres'

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