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A Mn(II) salt and A+CN− under anaerobic conditions react to form 2‐D and 3‐D extended structured compounds of AmMnIIn(CN)m+2n stoichiometry. Here, the creation and characterization of this large family of compounds, for example AMnII3(CN)7, A2MnII3(CN)8, A2MnII5(CN)12, A3MnII5(CN)13, and A2MnII[MnII(CN)6], where A represents alkali and tetraalkylammonium cations, is reviewed. Cs2MnII[MnII(CN)6] has the typical Prussian blue face centered cubic unit cell. However, the other alkali salts are monoclinic or rhombohedral. This is in accord with smaller alkali cation radii creating void space that is minimized by increasing the van der Waals stabilization energy by reducing ∠Mn−N≡C, which, strengthens the magnetic coupling and increases the magnetic ordering temperatures. This is attributed to the non‐rigidity of the framework structure due the significant ionic character associated with the high‐spin MnII sites. For larger tetraalkylammonium cations, the high‐spin Mn sites lack sufficient electrostatic A+⋅⋅⋅NC stabilization and form unexpected 4‐ and 5‐coordinated Mn sites within a flexible, extended framework around the cation; hence, the size, shape, and charge of the cation dictate the unprecedented stoichio‐metry and unpredictable cation adaptive structures. Antiferromagnetic coupling between adjacent MnII sites leads to ferrimagnetic ordering, but in some cases antiferromagnetic coupling of ferrimagnetic layers are compensated and synthetic antiferromagnets are observed. The magnetic ordering temperatures for ferrimagnetic A2MnII[MnII(CN)6] with both octahedral high‐ and low‐spin MnII sites increase with decreasing ∠Mn−N≡C. The crystal structures for all of the extended structured materials were obtained by powder diffraction. [ABSTRACT FROM AUTHOR]

The reaction of MnII(O2CMe)2 and NaCN or LiCN in water forms a light green insoluble material. Structural solution and Rietveld refinement of high‐resolution synchrotron powder diffraction data for this unprecedented, complicated compound of previously unknown composition revealed a new alkali‐free ordered structural motif with [MnII4(μ3‐OH)4]4+ cubes and octahedral [MnII(CN)6]4− ions interconnected in 3D by MnII‐N≡C‐MnII linkages. The composition is {[MnII(OH2)3][MnII(OH2)]3}(μ3‐OH)4][MnII(μ‐CN)2(CN)4]⋅H2O=[MnII4(μ3‐OH)4(OH2)6][MnII(μ‐CN)2(CN)4]⋅H2O, which is further simplified to [Mn4(OH)4][Mn(CN)6](OH2)7 (1). 1 has four high‐spin (S=5/2) MnII sites that are antiferromagnetically coupled within the cube and are antiferromagnetically coupled to six low‐spin (S=1/2) octahedral [MnII(CN)6]4− ions. Above 40 K the magnetic susceptibility, χ(T), can be fitted to the Curie–Weiss expression, χ ∝(T−θ)−1, with θ=−13.4 K, indicative of significant antiferromagnetic coupling and 1 orders as an antiferromagnet at Tc=7.8 K. Structural solution and Rietveld refinement of high‐resolution diffraction data for an unprecedented, complicated compound of previously unknown composition revealed a new alkali‐free ordered structural motif with [MnII4(μ3‐OH)4]4+ cubes and octahedral [MnII(CN)6]4− ions interconnected in 3D. [ABSTRACT FROM AUTHOR]

The article discusses a study on the crystal and molecular structures of the organic compound 2-ethoxybenzamide or C9H11NO2. The ribbon-like packing motifs were instigated by additional hydrogen bonds between adjacent dimers. A T-shaped herringbone pattern characterized the ribbons. The simulated annealing global optimization algorithm was used to solve the crystal structure.

We have determined the structures of two phases of unsolvated Mg(BH4)2, a material of interest for hydrogen storage. One or both phases can be obtained depending on the synthesis conditions. The first, a hexagonal phase with space group P61, is stable below 453 K. Upon heating above that temperature it transforms to an orthorhombic phase, with space group Fddd, stable to 613 K at which point it decomposes with hydrogen release. Both phases consist of complex networks of corner-sharing tetrahedra consisting of a central Mg atom and four BH4 units. The high-temperature orthorhombic phase has a strong antisite disorder in the a lattice direction, which can be understood on the basis of atomic structure. [ABSTRACT FROM AUTHOR]

Substitution of Ni for In in InTaO4 is reinvestigated by synchrotron X-ray and neutron powder diffraction, diffuse reflectance spectroscopy, XANES, and magnetic susceptibility measurements, providing insights into its previously reported photoactivity. [ABSTRACT FROM AUTHOR]

Cationic rearrangement is a compelling strategy for producing desirable physical properties by atomic-scale manipulation. However, activating ionic diffusion typically requires high temperature, and in some cases also high pressure in bulk oxide materials. Herein, we present the cationic rearrangement in bulk Mn2FeMoO6 at unparalleled low temperatures of 150-300 oC. The irreversible ionic motion at ambient pressure, as evidenced by real-time powder synchrotron X-ray and neutron diffraction, and second harmonic generation, leads to a transition from a Ni3TeO6-type to an ordered-ilmenite structure, and dramatic changes of the electrical and magnetic properties. This work demonstrates a remarkable cationic rearrangement, with corresponding large changes in the physical properties in a bulk oxide at unprecedented low temperatures. [ABSTRACT FROM AUTHOR]

Cationic rearrangement is a compelling strategy for producing desirable physical properties by atomic-scale manipulation. However, activating ionic diffusion typically requires high temperature, and in some cases also high pressure in bulk oxide materials. Herein, we present the cationic rearrangement in bulk Mn2FeMoO6 at unparalleled low temperatures of 150-300 oC. The irreversible ionic motion at ambient pressure, as evidenced by real-time powder synchrotron X-ray and neutron diffraction, and second harmonic generation, leads to a transition from a Ni3TeO6-type to an ordered-ilmenite structure, and dramatic changes of the electrical and magnetic properties. This work demonstrates a remarkable cationic rearrangement, with corresponding large changes in the physical properties in a bulk oxide at unprecedented low temperatures. [ABSTRACT FROM AUTHOR]

Purification of C2H4 from an C2H4 /C2H6 mixture is one of the most challenging separation processes, which is achieved mainly through energy‐intensive, cryogenic distillation in industry. Sustainable, non‐distillation methods are highly desired as alternatives. We discovered that the fluorinated bis(pyrazolyl)borate ligand supported copper(I) complex {[(CF3)2Bp]Cu}3 has features very desirable in an olefin–paraffin separation material. It binds ethylene exclusively over ethane generating [(CF3)2Bp]Cu(C2H4). This molecular compound exhibits extremely high and record ideal adsorbed solution theory (IAST) C2H4 /C2H6 gas separation selectivity, affording high purity (>99.5 %) ethylene that can be readily desorbed from separation columns. In‐situ PXRD provides a "live" picture of the reversible conversion between [(CF3)2Bp]Cu(C2H4) and the ethylene‐free sorbent in the solid‐state, driven by the presence or removal of C2H4. Molecular structures of trinuclear {[(CF3)2Bp]Cu}3 and mononuclear [(CF3)2Bp]Cu(C2H4) are also presented. [ABSTRACT FROM AUTHOR]

Purification of C2H4 from an C2H4 /C2H6 mixture is one of the most challenging separation processes, which is achieved mainly through energy‐intensive, cryogenic distillation in industry. Sustainable, non‐distillation methods are highly desired as alternatives. We discovered that the fluorinated bis(pyrazolyl)borate ligand supported copper(I) complex {[(CF3)2Bp]Cu}3 has features very desirable in an olefin–paraffin separation material. It binds ethylene exclusively over ethane generating [(CF3)2Bp]Cu(C2H4). This molecular compound exhibits extremely high and record ideal adsorbed solution theory (IAST) C2H4 /C2H6 gas separation selectivity, affording high purity (>99.5 %) ethylene that can be readily desorbed from separation columns. In‐situ PXRD provides a "live" picture of the reversible conversion between [(CF3)2Bp]Cu(C2H4) and the ethylene‐free sorbent in the solid‐state, driven by the presence or removal of C2H4. Molecular structures of trinuclear {[(CF3)2Bp]Cu}3 and mononuclear [(CF3)2Bp]Cu(C2H4) are also presented. [ABSTRACT FROM AUTHOR]

The reaction of MnII and [NEt4]CN leads to the isolation of solvated [NEt4]Mn3(CN)7 ( 1) and [NEt4]2Mn3(CN)8 ( 2), which have hexagonal unit cells [ 1: R $\bar 3$ m, a=8.0738(1), c=29.086(1) Å; 2: P $\bar 3$ m1, a=7.9992(3), c=14.014(1) Å] rather than the face centered cubic lattice that is typical of Prussian blue structured materials. The formula units of both 1 and 2 are composed of one low- and two high-spin MnII ions. Each low-spin, octahedral [MnII(CN)6]4− bonds to six high-spin tetrahedral MnII ions through the N atoms, and each of the tetrahedral MnII ions are bound to three low-spin octahedral [MnII(CN)6]4− moieties. For 2, the fourth cyanide on the tetrahedral MnII site is C bound and is terminal. In contrast, it is orientationally disordered and bridges two tetrahedral MnII centers for 1 forming an extended 3D network structure. The layers of octahedra are separated by 14.01 Å ( c axis) for 2, and 9.70 Å ( c/3) for 1. The [NEt4]+ cations and solvent are disordered and reside between the layers. Both 1 and 2 possess antiferromagnetic superexchange coupling between each low-spin ( S=1/2) octahedral MnII site and two high-spin ( S=5/2) tetrahedral MnII sites within a layer. Analogue 2 orders as a ferrimagnet at 27(±1) K with a coercive field and remanent magnetization of 1140 Oe and 22 800 emuOe mol−1, respectively, and the magnetization approaches saturation of 49 800 emuOe mol−1 at 90 000 Oe. In contrast, the bonding via bridging cyanides between the ferrimagnetic layers leads to antiferromagnetic coupling, and 3D structured 1 has a different magnetic behavior to 2. Thus, 1 is a Prussian blue analogue with an antiferromagnetic ground state [ Tc=27 K from d( χT)/d T]. [ABSTRACT FROM AUTHOR]

A modification to the usual least-squares analysis is implemented for the robust refinement of structural parameters from powder diffraction data in the presence of unmodeled impurities. This is accomplished in the program TOPAS-Academic by an iterative reweighting of the data as the model is refined. The method is tested and characterized using mixtures of known materials, acetaminophen and ibuprofen. The technique is also used to refine two previously unknown structures. [ABSTRACT FROM AUTHOR]

The reactions of MnII(O2CCH3)2 with NEt3Me+CN− and NEt2Me2+CN− form (NEt3Me)2MnII5(CN)12 (1) and (NEt2Me2)2MnII5(CN)12 (2), respectively. Structure model‐building and Rietveld refinement of high‐resolution synchrotron powder diffraction data revealed a cubic [a=24.0093 Å (1), 23.8804 Å (2)] 3D extended structural motif with adjacent tetrahedral and octahedral MnII sites in a 3:2 ratio. Each tetrahedral MnII site is surrounded by four low‐spin octahedral MnII sites, and each octahedral MnII site is surrounded by six high‐spin tetrahedral MnII sites; adjacent sites are antiferromagnetically coupled in 3D. Compensation does not occur, and magnetic ordering as a ferrimagnet is observed at Tc=13 K for 2 based on the temperature at which remnant magnetization, Mr(T)→0. The hysteresis has an unusual constricted shape with inflection points around 50 and 1.2 kOe with a 5 K coercivity of 16 Oe and remnant magnetization, Mr, of 2050 emuOe mol−1. The unusual structure and stoichiometry are attributed to the very ionic nature of the high‐spin N‐bonded MnII ion, which enables the maximization of the attractive van der Waals interactions through minimization of void space via a reduced ∠ MnNC. This results in an additional example of the AxMnIIy(CN)x+2y (x=0, y=1; x=1, y=3; x=2, y=1; x=2, y=2; x=2, y=3; x=3, y=5; and x=4, y=1) family of compounds possessing an unprecedented stoichiometry and lattice motif that are cation adaptive structured materials. [ABSTRACT FROM AUTHOR]

Treating deuterohemin, chloro(deuteroporphyrinato)iron(III), with a non‐coordinating base in DMSO/methanol allows for the isolation of [(deuteroporphyrinato)iron(III)]2, deuterohematin anhydride (DHA), an analogue of malaria pigment, the natural product of heme detoxification by malaria. The structure of DHA obtained from this solvent system has been solved by X‐ray powder diffraction analysis and displays many similarities, yet important structural differences, to malaria pigment. Most notably, a water molecule of solvation occupies a notch created by the propionate side chains and stabilizes a markedly bent propionate ligand coordinated with a long Fe−O bond, and a carboxylate cluster associated with water molecules is generated. Together, these features account for its increased solubility and more open structure, with an increased porphyrin–porphyrin separation. The IR spectroscopic signature associated with this structure also accounts for the strong IR band at 1587 cm−1 seen for many amorphous preparations of synthetic malaria pigment, and it is proposed that stabilizing these structures may be a new objective for antimalarial drugs. The important role of the vinyl substituents in this biochemistry is further demonstrated by the structure of deuterohemin obtained by single‐crystal X‐ray diffraction analysis. Hemozoin‐like structure: A new structural motif for heme dimerization relevant to malarial heme processing and aggregation has been found for the iron(deuteroporphyrin) dimer. [ABSTRACT FROM AUTHOR]

The frontpiece of the journal is presented depicting cationic rearrangement in metal oxide.

Engineering auf atomarer EbeneIn der Zuschrift auf S. 10016 ff. beschreiben M. Greenblatt et al., wie eine kationische Umlagerung in Mn2FeMoO6 bei niedriger Temperatur zu einer geordneten Ilmenit ‐ Struktur mit neuen magnetischen und elektrischen Eigenschaften führt. [ABSTRACT FROM AUTHOR]

Pb2MReO6 (M: Co (I), Cr (II)) perovskites are prepared by hot pressing of stoichiometric amounts of PbO, Cr2O3 (CoO), Re, and ReO3 (Pt capsule in multianvil press, 1423 (I) and 1473 K (II), 8 GPa, 30 min). [ABSTRACT FROM AUTHOR]

The first transition-metal-only double perovskite compound, Mn2+2Fe3+Re5+O6, with 17 unpaired d electrons displays ferrimagnetic ordering up to 520 K and a giant positive magnetoresistance of up to 220 % at 5 K and 8 T. These properties result from the ferrimagnetically coupled Fe and Re sublattice and are affected by a two-to-one magnetic-structure transition of the Mn sublattice when a magnetic field is applied. Theoretical calculations indicate that the half-metallic state can be mainly attributed to the spin polarization of the Fe and Re sites. [ABSTRACT FROM AUTHOR]

The first transition-metal-only double perovskite compound, Mn2+2Fe3+Re5+O6, with 17 unpaired d electrons displays ferrimagnetic ordering up to 520 K and a giant positive magnetoresistance of up to 220 % at 5 K and 8 T. These properties result from the ferrimagnetically coupled Fe and Re sublattice and are affected by a two-to-one magnetic-structure transition of the Mn sublattice when a magnetic field is applied. Theoretical calculations indicate that the half-metallic state can be mainly attributed to the spin polarization of the Fe and Re sites. [ABSTRACT FROM AUTHOR]

Above-room-temperature polar magnets are of interest due to their practical applications in spintronics. Here we present a strategy to design high-temperature polar magnetic oxides in the corundum-derived A2BB′O6 family, exemplified by the non-centrosymmetric ( R3) Ni3TeO6-type Mn2+2Fe3+Mo5+O6, which shows strong ferrimagnetic ordering with TC=337 K and demonstrates structural polarization without any ions with ( n−1)d10 ns0, d0, or stereoactive lone-pair electrons. Density functional theory calculations confirm the experimental results and suggest that the energy of the magnetically ordered structure, based on the Ni3TeO6 prototype, is significantly lower than that of any related structure, and accounts for the spontaneous polarization (68 μC cm−2) and non-centrosymmetry confirmed directly by second harmonic generation. These results motivate new directions in the search for practical magnetoelectric/multiferroic materials. [ABSTRACT FROM AUTHOR]

Above-room-temperature polar magnets are of interest due to their practical applications in spintronics. Here we present a strategy to design high-temperature polar magnetic oxides in the corundum-derived A2BB′O6 family, exemplified by the non-centrosymmetric ( R3) Ni3TeO6-type Mn2+2Fe3+Mo5+O6, which shows strong ferrimagnetic ordering with TC=337 K and demonstrates structural polarization without any ions with ( n−1)d10 ns0, d0, or stereoactive lone-pair electrons. Density functional theory calculations confirm the experimental results and suggest that the energy of the magnetically ordered structure, based on the Ni3TeO6 prototype, is significantly lower than that of any related structure, and accounts for the spontaneous polarization (68 μC cm−2) and non-centrosymmetry confirmed directly by second harmonic generation. These results motivate new directions in the search for practical magnetoelectric/multiferroic materials. [ABSTRACT FROM AUTHOR]

When the influenza A ( H1 N1) pandemic spread across the globe from April 2009 to August 2010, many WHO Member States used antiviral drugs, specifically neuraminidase inhibitors ( NAIs) oseltamivir and zanamivir, to treat influenza patients in critical condition. Antivirals have been found to be effective in reducing severity and duration of influenza illness, and likely reduce morbidity; however, it is unclear whether NAIs used during the pandemic reduced H1 N1 mortality. To assess the association between antivirals and influenza mortality, at an ecologic level, country-level data on supply of oseltamivir and zanamivir were compared to laboratory-confirmed H1 N1 deaths (per 100 000 people) from July 2009 to August 2010 in 42 WHO Member States. From this analysis, it was found that each 10% increase in kilograms of oseltamivir, per 100 000 people, was associated with a 1·6% reduction in H1 N1 mortality over the pandemic period [relative rate ( RR) = 0·84 per log increase in oseltamivir supply]. Each 10% increase in kilogram of active zanamivir, per 100 000, was associated with a 0·3% reduction in H1 N1 mortality ( RR = 0·97 per log increase). While limitations exist in the inference that can be drawn from an ecologic evaluation, this analysis offers evidence of a protective relationship between antiviral drug supply and influenza mortality and supports a role for influenza antiviral use in future pandemics. This article summarises the original study described previously, which can be accessed through the following citation: Miller PE, Rambachan A, Hubbard RJ, Li J, Meyer AE, et al. (2012) Supply of Neuraminidase Inhibitors Related to Reduced Influenza A (H1N1) Mortality during the 2009-2010 H1N1 Pandemic: An Ecological Study. PLoS ONE 7(9): e43491. [ABSTRACT FROM AUTHOR]

Polar LiNbO3‐type magnetic oxides have been extended, for the first time, to the A2BB′O6 family. Mn2+2Fe3+M5+O6 (M=Nb, Ta), synthesized at high pressure, adopt a polar structure, as demonstrated by electron diffraction and the second harmonic generation effect, and they have interesting magnetic properties. [ABSTRACT FROM AUTHOR]

Hochdruckgebiet: Polare magnetische Oxide vom LiNbO3 ‐ Typ wurden erstmals auf die A2BB′O6 ‐ Familie ausgedehnt. Bei hohem Druck synthetisierte Oxide mit der allgemeinen Summenformel Mn2+2Fe3+M5+O6 (M=Nb, Ta) nehmen eine polare Struktur ein, wie durch Elektronenbeugung und den Frequenzverdopplungseffekt gezeigt wurde, und zeigen interessante magnetische Eigenschaften. [ABSTRACT FROM AUTHOR]

Compounds (II) and [NEt4][Mn3(CN)8]·0.5H2O (III) are characterized by powder XRD and magnetic measurements. [ABSTRACT FROM AUTHOR]

Review: 37 refs. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated multicenter bonding in dianionic tetracyanoethylene (TCNE) dimers through Raman spectroscopy. In this study, the stretching force constant 0.45 mdyn Å-1 was determined through analysis of the Raman spectrum of K2[TCNE]2. The study shows that the long, multicenter intradimer bond in the π-[TCNE]22-dimer is stronger compared with some hydrogen bonds.

The article discusses research which aims to analyze the Raman vibrational spectra of dianionic tetracyanoethylene (TCNE) dimers. It reports experimental details including information on TCNE multicenter bonds, strength estimation of multicenter C--C bonds, and stretching force constant identification. It describes vibrational normal modes related to relevant Raman bands. It also evaluated temperature dependence of low-frequency bands in the Raman spectra.

The article discusses a study on the solution of the crystal structure of the hidden super lattice in isostructural compounds TI2 (SC6H4S) and TI2 (SeC6H4Se) by simulated annealing from high resolution synchrotron X-ray powder diffraction. It also discusses the synthesis of this isostructural compounds by electric conductivity of metal arenethiolate. The interaction of TI-S or TI-Se bonds is also discussed.

The article presents a study that evaluates the use of powder diffraction on crystalline mixtures. It shows that the disparities in the data among the three sets of diffraction measurements described are non-statistical in nature. It suggests that the extinction effect should be considered with regard to all quantitative phase analysis experiments on highly crystalline materials.

The crystal structure of ampicillin trihydrate {systematic name: 6-[d(−)-α-amino­phenyl­acetamido]penicillanic acid trihydrate}, C16H19N3O4S·3H2O, a broad-spectrum β-lactam anti­biotic of the amino­penicillin type, has been determined from synchrotron X-ray powder diffraction data. The three water molecules form an infinite hydrogen-bonded chain through the crystal structure, with hydrogen bonds to the NH3+, COO−, C=O and NH groups of the ampicillin molecules. [ABSTRACT FROM AUTHOR]

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Cyclooxygenase-2 (COX-2) inhibitors are selective nonsteroidal anti-inflammatory drugs (NSAIDs), purported to demonstrate lower gastrointestinal toxicity than nonselective NSAIDs. • Prescriptions of selective COX-2 inhibitors declined internationally after 2004 following voluntary withdrawal and regulatory intervention because of possible cardiovascular side-effects. • A study in Canada indicated that rates of gastrointestinal haemorrhage actually increased during the period of increasing COX-2 inhibitor prescriptions, due to the increased number of people receiving NSAIDs. WHAT THIS STUDY ADDS • The reduction in availability of COX-2 inhibitors in the UK was temporally associated with a favourable reversal of the trend in emergency hospital admissions for acute myocardial infarction among people aged ≥65 years, but there were no related changes in myocardial infarction mortality trends. • There was some indication that hospital admissions for gastrointestinal haemorrhage among people aged 55–64 years started to increase following a previously declining trend, but this change predated withdrawal/regulation of COX-2 inhibitors by up to 2 years. • The withdrawal/regulation of coxibs did not appear to have any adverse impact on population health and may have been beneficial. AIMS To investigate impacts of withdrawal and regulatory advice regarding cyclooxygenase-2 (COX-2) inhibitors on UK population rates of gastrointestinal haemorrhage and acute myocardial infarction (MI). METHODS Ecological time series study of prescribing, mortality and hospital admission trends in people aged ≥55 years. RESULTS Withdrawal and regulatory advice limiting COX-2 inhibitor availability from 2004 were temporally associated with reversal of previously unfavourable trends in emergency MI admissions among people aged ≥65 years. Annual admission rate trends changed from +4.6% to −3.1% ( P < 0.001) among women and from +2.1% to −3.8% ( P= 0.003) among men. Absolute changes in average annual trend in the number of individuals aged ≥65 years admitted following MI were from +981 (1999–2004) to −819 (2004–2006) per year for women and from +713 to −995 for men. No change in trend was apparent among people aged 55–64 years, or in MI mortality trends. There was some suggestion of an unfavourable change in admission trends for gastrointestinal haemorrhage among 55−64-year-olds, although this appeared to occur prior to COX-2 inhibitor withdrawal/regulation by up to 2 years. These trends were not apparent in older people, or in gastrointestinal haemorrhage mortality rates. CONCLUSIONS Withdrawal/regulation of COX-2 inhibitors was temporally associated with a favourable reversal of population-level hospital admission trends in MI among people aged ≥65 years. Unfavourable reversal of previous declines in gastrointestinal haemorrhage admissions probably occurred before changes in COX-2 inhibitor availability. Withdrawal/ regulation of COX-2 inhibitors did not appear to have any adverse impact on population health and may have been beneficial. [ABSTRACT FROM AUTHOR]

The discovery of ligands that bind specifically to a targeted protein benefits from the development of generic assays for high-throughput screening of a library of chemicals. Protein powder diffraction (PPD) has been proposed as a potential method for use as a structure-based assay for high-throughput screening applications. Building on this effort, powder samples of bound/unbound states of soluble hen-egg white lysozyme precipitated with sodium chloride were compared. The correlation coefficients calculated between the raw diffraction profiles were consistent with the known binding properties of the ligands and suggested that the PPD approach can be used even prior to a full description using stereochemically restrained Rietveld refinement. [ABSTRACT FROM AUTHOR]

OBJECTIVE To aid the interpretation of the trends in prostate cancer mortality, which declined in the UK in the early 1990s for unknown reasons, by investigating prostate cancer death rates, incidence and treatments in England and Wales in 1975–2004. METHODS Join-point regression was used to assess secular trends in mortality and incidence (source: Office of National Statistics), radical prostatectomy and orchidectomy (source: Hospital Episode Statistics database) and androgen-suppression drugs (source: Intercontinental Medical Statistics). RESULTS Prostate cancer mortality declined from 1992 (95% confidence interval, CI, 1990–94). The relative decline in mortality to 2004 was greater and more sustained amongst men aged 55–74 years (annual percentage mortality reduction 2.75%; 95% CI 2.33–3.18%) than amongst those aged ≥75 years (0.71%, 0.26–1.15%). The use of radical prostatectomy increased between 1991 (89 operations) and 2004 (2788) amongst men aged 55–74 years. The prescribing of androgen suppression increased between 1987 (33 000 prescriptions) and 2004 (470 000). CONCLUSIONS The decrease in prostate cancer mortality was greater amongst men aged 55–74 years than in those aged ≥75 years, but pre-dated the substantial use of prostate-specific antigen screening and radical prostatectomy in the UK. An increase in radical therapy amongst younger groups with localized cancers and screen-detected low-volume locally advanced disease as a result of stage migration, as well as prolonged survival from increased medical androgen suppression therapy, might partly explain recent trends. [ABSTRACT FROM AUTHOR]

Reports that the compounds tetrakis(trimethylsilyl)methane (TC) and tetrakis(trimethylsilyl)silane (TSi) have crystal structures with the molecules in a cubic closed-packed stacking. Space group at room temperature of both structures; Description of an X-ray scattering data by a molecule with approximately sixfold orientational disorder, ruling out structure with free rotating molecules.

A further example of using a covalent-bond-forming reaction to alter supramolecular assembly by modification of hydrogen-bonding possibilities is presented. This concept was introduced by Lemmerer, Bernstein & Kahlenberg [ CrystEngComm (2011), 13, 55-59]. The title structure, C9H11N3O·C7H6O4, which consists of a reacted niazid molecule, viz. N′-(propan-2-ylidene)nicotinohydrazide, and 2,4-dihydroxybenzoic acid, was solved from powder diffraction data using simulated annealing. The results further demonstrate the relevance and utility of powder diffraction as an analytical tool in the study of cocrystals and their hydrogen-bond interactions. [ABSTRACT FROM AUTHOR]

Two new oxynitride phases are discovered in the title system by high-pressure synthesis using state of the art crystal structure prediction theory and in situ synchrotron-based X-ray scattering. [ABSTRACT FROM AUTHOR]