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A novel approach to computationally enhance the sampling of molecular crystal structures is proposed and tested. This method is based on the use of extended variables coupled to a Monte Carlo based crystal polymorph generator. Inspired by the established technique of quasi‐random sampling of polymorphs using the rigid molecule constraint, this approach represents molecular clusters as extended variables within a thermal reservoir. Polymorph unit‐cell variables are generated using pseudo‐random sampling. Within this framework, a harmonic coupling between the extended variables and polymorph configurations is established. The extended variables remain fixed during the inner loop dedicated to polymorph sampling, enforcing a stepwise propagation of the extended variables to maintain system exploration. The final processing step results in a polymorph energy landscape, where the raw structures sampled to create the extended variable trajectory are re‐optimized without the thermal coupling term. The foundational principles of this approach are described and its effectiveness using both a Metropolis Monte Carlo type algorithm and modifications that incorporate replica exchange is demonstrated. A comparison is provided with pseudo‐random sampling of polymorphs for the molecule coumarin. The choice to test a design of this algorithm as relevant for enhanced sampling of crystal structures was due to the obvious relation between molecular structure variables and corresponding crystal polymorphs as representative of the inherent vapor to crystal transitions that exist in nature. Additionally, it is shown that the trajectories of extended variables can be harnessed to extract fluctuation properties that can lead to valuable insights. A novel thermodynamic variable is introduced: the free energy difference between ensembles of Z′ = 1 and Z′ = 2 crystal polymorphs. [ABSTRACT FROM AUTHOR]

Reactions of lanthanide chlorides or trifluoracetates (tfa) or picrates with trimethylphosphate alone in the first two cases or trimethylphosphate plus 1,10-phenanthroline or 2,2′;6′,2′′-terpyridine in the third, result in the formation of crystalline products containing dimethylphosphate (dmp–). Single crystal X-ray structural characterisation of these materials has shown that the stoichiometrically simple Ln(dmp)3 species obtained with chloride reactants and the lighter lanthanides are polymeric and commonly dimorphic, while the stoichiometrically more variable mixed dmp/tfa complexes have structures closely related to one phase of the Ln(dmp)3 family, and the presence of picrate and aza-aromatic ligands enables the isolation of Y and Lu derivatives containing binuclear species. In all, the dmp– ligands adopt exclusively the κ1 O ;κ1 O′ bridging mode, the overall results indicating that this should apply to the complete lanthanide series. Structural studies of the products of reaction of different lanthanide(III) salts with trimethylphosphate show them to contain dimethylphosphate as a bridging bidentate rather than a chelate ligand across the lanthanide series. [ABSTRACT FROM AUTHOR]

Reactions of the lanthanide(iii) picrates (picrate = 2,4,6-trinitrophenoxide = pic) with 1,10-phenanthroline (phen) and 2,2′:6′,2′′-terpyridine (terpy) in a 1 : 2 molar ratio have provided crystals suitable for X-ray structure determinations in instances predominantly involving the lighter lanthanides. In all, the aza-aromatic ligands chelate the lanthanide ion, none being found as 'free' ligands within the lattice. The complexes of 1,10-phenanthroline have been characterised in two forms, one unsolvated (Ln = La, Sm, Eu; monoclinic, C 2/ c , Z 8), one an acetonitrile monosolvate (Ln = Gd; monoclinic, P 21/ a , Z 4), the latter being the only previously known form (with Ln = La). In both forms, the LnIII is nine-coordinate, in an approximately tricapped trigonal-prismatic environment, with two picrate ligands chelating through phenoxide and 2-nitro group oxygen atoms, the third being bound through phenoxide-O only. The 2,2′:6′,2′′-terpyridine complexes, all acetonitrile monosolvates defined for Ln = La, Gd, Er, and Y (monoclinic, C 2/ c , Z 4), are ionic, one picrate having been displaced from the primary coordination sphere. For Ln = La, the two bound picrates are again chelating, making the LaIII 10-coordinate in a distorted bicapped square-antiprismatic environment but in the other species they are bound through phenoxide-O only, making the LnIII ions eight-coordinate in a distorted square-antiprismatic environment. Stacked arrays of the ligands can be found in both series of complexes, with intramolecular picrate–picrate and picrate–aza-aromatic stacks being prominent features. Structure determinations on complexes of lanthanide(III) picrates with aza-aromatic ligands provide examples of various stacking arrays. The chain of [La(terpy)2(pic)2]+ cations (shown in space-filling mode) present in the lattice of [La(terpy)2(pic)2](pic)·CH3CN involves both intra- and intermolecular heterogeneous stacks. [ABSTRACT FROM AUTHOR]

The carboxamide-O donor ligands dimethylacetamide (dma) and N -methylpyrrolidinone (nmp) form complexes of lanthanide picrates, Ln(pic)3, of stoichiometry Ln(pic)3(carboxamide)3 in a remarkable variety of phases. Complexes [Ln(pic)3(dma)3], Ln = La, Ce, Nd, Sm, Gd, Yb, Lu, and Y, adopt the 9-coordinate molecular form of tricapped trigonal-prismatic coordination geometry seen to predominate, as two stereoisomers, in related species involving dimethylsulfoxide (dmso), trimethylphosphate (tmp), and hexamethylphosphoramide (hmpa) but as four different phases (depending on Ln), none of which is the same as for the previously known La complex. For Ln = Pr, 9-coordinate species of composition [Pr(pic)3(dma)2(alcohol)] (alcohol = ethanol and propan-2-ol) have been characterised and a low quality determination indicates that a similar species (with propan-2-ol) is formed by Y. For nmp, the composition [Ln(pic)3(nmp)3] is maintained across the series for Ln = La, Ce, Pr, Nd, Gd, Er, Tm, Yb, and Lu but 9-coordination is not for Ln = Er, Tm, Yb, and Lu. A decreased coordination there is a result of one or two picrate ligands acting as phenoxide-O donors only, a marked contrast with the analogous Ln(pic)3 complexes with dmso, tmp, hmpa, and dma, where picrate chelation is universal, but with some parallel to related ScIII complexes. Several polymorph pairs can be identified among the nmp complexes. Structural studies of the adducts of lanthanide picrates with dimethylacetamide (dma) and N-methylpyrrolidinone (nmp) add further variety to the nature of simple O-donor ligand complexes of these picrates. Polymorphism is readily detected in the dma complexes, while, with the heavier lanthanides, nmp causes partial detachment of the picrate ligands. [ABSTRACT FROM AUTHOR]

Adducts of dimethylsulfoxide, dmso = Me2SO, with lanthanide(iii) picrates (picrate = 2,4,6-trinitrophenoxide, pic) of stoichiometry Ln(pic)3·3dmso have been prepared and characterised by single-crystal X-ray structure determinations as discrete, neutral, mononuclear molecular species. Such complexes have been obtained across the gamut of Ln, specifically for Ln = La, Pr, Nd, Sm, Gd, Dy, Yb, Lu, and Y, presumably also accessible for other intermediate members, the series being isomorphous (monoclinic, C 2/ c , Z = 8); a second triclinic P CH19169_IE1.gif form has also been identified for Ln = La, Pr. In both forms, the metal atom coordination environments are nine-coordinate, tricapped trigonal prismatic, [Ln(dmso- O)3(pic- O,O′)3], two of the three unidentate ligands lying in one of the trigonal planes and one in the other (an isomer we have termed meridional, mer). A hydrated form of Ln(pic)3·2dmso·H2O stoichiometry has also been defined for Ln = Sm, Gd, Lu, the metal atom environment again nine-coordinate, [Ln(dmso- O)2(H2 O)(pic- O,O′)3], but now fac , with the three unidentate ligands occupying one triangular face of the tricapped trigonal prism and involved in a centrosymmetric H-bonding array with the three similar ligands of an adjacent complex; the three capping atoms are nitro-oxygen atoms, the phenoxy- O triad occupying the other face. Structural characterisation of adducts of lanthanide picrates with dimethylsulfoxide has provided evidence that the 9-coordinate, tricapped trigonal-prismatic, mer -[Ln(pic)3(dmso)3] form with chelating picrate ligands may extend through the full series. Partial aquation of the tris(dmso) complexes to [Ln(pic)3(dmso)2(OH2)] provides three examples of an otherwise similar but facial isomer. [ABSTRACT FROM AUTHOR]

Single crystal X-ray structural characterisations are reported for adducts of the form [(L- O)Eu(O , O ′-dpm)3] obtained by the crystallisation of tris(dipivaloylmethanato)europium(iii) (dpm = [HC(C(tBu).CO)2]−) from an array of dipolar aprotic oxygen-donor solvents L (L = N -methylpyrrolidinone (nmp), trimethylphosphate, (MeO)3PO, (tmp), hexamethylphosphoramide (hmpa), dimethylacetamide (dma), dimethyl sulfoxide (dmso), and the bidentate octamethylpyrophosphoramide (ompa). In all adducts, the resulting arrays contain seven-coordinate metal atoms, which adopt two different isomeric forms of the mono-capped trigonal prismatic stereochemistry, the L = dma and dmso adducts corresponding to one type, nmp and tmp the other. The adduct formed with ompa behaves as a pair of discrete metal environments bridged by the O -ompa- O ′ ligand, thus; [(dpm- O , O ′)3Eu(O -ompa- O ′)Eu(O , O ′-dpm)3], and is found in two forms, one in which both Eu environments is of the tmp type, the other of the dmso/dma type. In the hmpa adduct, the asymmetric unit of the structure is a disordered composite of both types. In none of the adducts is there any further solvation beyond coordination of a single L. Structural studies of crystalline adducts of [Eu(dipivaloylmethanato)3] with dmso, dma, tmp, hmpa, and ompa have shown all to contain seven-coordinate EuIII. This low coordination number appears to be a consequence of partial coordination sphere interpenetration in the solid state. [ABSTRACT FROM AUTHOR]

Crystalline products of the reactions of lanthanide picrates, Ln(pic)3 (pic = 2,4,6-trinitrophenoxide), with hexamethylphosphoramide (hmpa) and octamethylpyrophosphoramide (ompa) have been characterised by single-crystal X-ray diffraction studies. With hmpa and lighter lanthanides (La, Sm, Eu), isomorphous species (monoclinic, P 21/ c , Z 4) of stoichiometry [Ln(pic)3(hmpa)3]·0.5H2O, have been defined where the molecular units in the lattice contain 9-coordinate Ln with tricapped trigonal-prismatic coordination geometry. The picrate ligands are bidentate through phenoxide-O and 2-nitro-O, with the latter occupying the capping positions, while the hmpa ligands are singly O-bound to one trigonal face. Heavier lanthanides (Gd, Lu) and Y have been found to give isomorphous (monoclinic, P 21/ n , Z 4) species of stoichiometry [Ln(pic)3(hmpa)2], with 8-coordinate Ln of an irregular geometry best considered as close to that of a bicapped trigonal-prism. The picrate ligands chelate in the same manner as in the lighter Ln complexes but with one spanning a trigonal edge, and the hmpa-O donors occuping two apices of the other trigonal face. The ligand ompa has been found to act as a bidentate chelate in all isolated species, displacing one picrate from the metal ion coordination sphere to give ionic complexes. For La, Nd, and Gd, isomorphous (monoclinic, P 21/ n , Z 4) complexes of stoichiometry [Ln(pic)2(ompa)2(OH2)](pic)·0.5H2O containing 9-coordinate, tricapped trigonal-prismatic Ln with a single aqua ligand have been defined, while for Er, Yb, Lu, and Y, both the coordinated and lattice water molecules are lost in isomorphous (monoclininc, P 21/ c , Z 8) 8-coordinate, square-antiprismatic species of stoichiometry [Ln(pic)2(ompa)2](pic). For Er, further polymorphs, one monoclinic, P 21/ c , and the other triclinic, CH19251_IE1.gif , have also been characterised. Structural studies of adducts of the lanthanide picrates with hexamethylphosphoramide (hmpa) and octamethylpyrophosphoramide (ompa) provide significant contrasts with those of analogous adducts with dimethylsulfoxide and trimethylphosphate. Adducts of hmpa show a transition from 9-coordinate (hmpa)3 to 8-coordinate (hmpa)2 species, while ompa displaces one picrate from the primary coordination sphere. [ABSTRACT FROM AUTHOR]

Adducts of the form Ln(pic)3(tmp)3 (Ln = lanthanide(iii); pic = picrate = 2,4,6-trinitrophenoxide; tmp = trimethylphosphate, (MeO)3PO) have been prepared for extremal Ln = La, Lu and some intermediate members, also Y, and characterised by single crystal X-ray structure determinations as unsolvated, mononuclear, molecular species. The lanthanide atom has nine-coordinate, tri-capped trigonal prismatic stereochemistry in all cases, the picrate components behaving as O , O ′-bidentate ligands chelating through the phenoxy- and an adjacent O -nitro oxygen atom, thus: [Ln(tmp- O)3(pic- O , O ′)3]. Two isomeric forms are found, one mer in which the three unidentate tmp- O ligands coordinate in cis -sites spanning the upper and lower triangles and a capping site of the coordination sphere, and fac , in which all three unidentate ligands occupy the mutually cis -sites of one triangular face. The mer isomer has been described as an isomorphous series in a monoclinic P 21/ c , Z 4, form, for Ln = La, Ce, Pr, Nd, Sm, Gd, Lu, and Y, presumptively accessible for the full gamut of Ln. The fac -isomer also crystallises in a monoclinic P 21/ c form, Z 8, two independent molecules of similar stereochemistry here comprising the asymmetric unit and described for Ln = Eu, Lu(isomorphous); it has also been described in a triclinic P CH19176_IE1.gif , Z 2 form for Ln = La. Trimethylphosphate (tmp) is the first of a series of related O-donor solvates of lanthanide(III) picrates to give isomeric mer- and fac- [Ln(pic)3(tmp)3] complexes. [ABSTRACT FROM AUTHOR]

Addition of various oxygen-donor ligands (L, all dipolar, aprotic solvents), to a solution of hydrated scandium picrate in weakly coordinating solvents (S), has yielded several crystalline adducts of the form Sc(pic)3(L) m (· n S) in which all ligands L are coordinated, subsequently characterised by a series of single crystal X-ray studies. For L = dmso, m = 3 and the picrate anions are all bound as phenoxide-O donor units, while for nmp, dma, tmp, and hmpa, m = 2 and one of the bound picrates becomes bidentate through phenoxide- and nitro-O donation. For L = ompa, m = 2 and two picrate ligands are bound through phenoxide-O while one is displaced from the primary coordination sphere. All complexes contain six-coordinate ScIII, confirming that this coordination number is a consequence of ligand bulk. Six-coordination of ScIII is observed throughout in crystalline adducts of scandium picrate with dmso, dma, nmp, tmp, hmpa, and ompa, although with variations in the adduct stoichiometry and the coordination mode of picrate. [ABSTRACT FROM AUTHOR]

The redox properties and the reactivity of several areneruthenium(II) 4-acyl-5-pyrazolonate derivatives are described.

The following report outlines a simplified method to predict the effect on the relative growth rates of crystal facets resulting from different solvents. The method uses molecular dynamics (MD) techniques which are coupled to a Monte Carlo (MC) scheme to generate distributions of estimates of molecular binding energies at the crystal surface. We then use these calculated binding energies to make inferences on how solvent may affect the relative growth rate of the crystal facets (i.e., solvent effect on growth). We support the analysis by revisiting the growth of adipic acid. It is demonstrated that there is a remarkable increase in the sensitivity of the expected values used to represent the "solvent effect on growth" when a very simple correction for the molecular size between solute and solvent is implemented into the Monte Carlo scheme. The use of single point energy calculations (potential energy) displays limited sensitivity to the expected solvent effect in comparison to the use of distributions of MD derived values (binding free energy). Thus, the combination of relative binding free energy data and the proposed MC scheme is believed to be an effective path forward to providing insight into a solvent or additive effect on growth for more complex molecular systems that is simple to implement and does not come at a significantly high computational expense. In order to make an assessment of the data from simulation, plotting of the relative growth effect curvature is also introduced. [ABSTRACT FROM AUTHOR]

A model for predicting supersaturation, crystal growth rate, crystal size distribution, and aspect ratio is presented. The model applies to isothermal anti-solvent crystallization where crystal growth is the dominant phenomena and for systems where crystal habit can be characterized by two-dimensional variables. A parameter estimation algorithm was derived to extract solute integration coefficients in the two growth directions from experimental data about temporal evolution of concentration during crystallization, the final aspect ratio, and the aspect ratio at the end of the seed age period. Model's predictions for supersaturation and aspect ratio were in good agreement with experimental data obtained on an investigational drug that crystallizes in the parallelepipedic shape. Finally, model simulations predict that for a given initial seed size, the seed loading is the main factor impacting the final aspect ratio and thus identified the range of seed loading that would result in undesired powder flow. © 2015 American Institute of Chemical Engineers AIChE J, 61: 4456-4469, 2015 [ABSTRACT FROM AUTHOR]

Single crystal X-ray structure determinations have previously been described for picrate salts of a variety of nitrogen bases. Herein, these have been extended to encompass monoprotonated mono- and oligo-dentate cyclic nitrogen-donor ligand systems derived from pyridine, some via saturation (piperidine and morpholine) and others via lateral extension of the aromatic system (2,2'-bipyridine, 1,10-phenanthroline, 2,9-dimethyl-1,10-phenanthroline, bis(2-pyridyl)amine, 2,2':6',2"-terpyridine, and 8-hydroxyquinoline). Hydrogen-bonding interactions are dominant determinants of the structures, complemented by or in competition with parallel stacking of anion and (aromatic) base planes. Furthermore, nitro⋯nitro, nitro⋯7i and phenoxy-0⋯7i inter-species contacts play a significant role in the crystal packing. It also appears that cation...anion interactions arising from CH(adjacent to NH)⋯O(o-nitro) interactions are more important than the available secondary bifurcating component associated with any NH⋯O(o-nitro) approach, resulting, in many cases, in a bidentate NH⋯HC base approach to an (ON)O⋯O⋯O(NO) triadic array. The nature of the anion-cation interactions and their importance are explored using the Hirshfeld surface method. The precision of the structure determinations establishes the quinonoid form of the picrate to be a widespread contributor. Theoretical calculations on picric acid and the parent pyridinium-picrate ion-pair confirm the energetic favourability of the base-triad approach and the dominance of the quinonoid resonance form. [ABSTRACT FROM AUTHOR]

A low-temperature structural phase transition has been observed for form (II) of benzocaine (BZC). Lowering the temperature doubles the b-axis repeat and changes the space group from P212121 to P1121 with y now 99.37°. The structure is twinned, the twin rule corresponding to a 21 screw rotation parallel to a. The phase transition is associated with a sequential displacement parallel to a of zigzag bi-layers of ribbons perpendicular to b*. No similar phase transition was observed for form (I) and this was attributed to the different packing symmetries of the two room-temperature polymorphic forms. [ABSTRACT FROM AUTHOR]

In this paper, theories on anisotropic crystal growth and crystallization of atropisomers are reviewed and a model for anisotropic crystal growth from solution containing slow inter-converting conformers is presented. The model applies to systems with growth-dominated crystallization from solutions and assumes that only one conformation participates in the solute integration step and is present in the crystal lattice. Other conformers, defined as the wrong conformers, must convert to the right conformer before they can assemble to the crystal lattice. The model presents a simple implicit method for evaluating the growth inhibition effect by the wrong conformers. The crystal growth model applies to anisotropic growth in two main directions, namely a slow-growing face and a fast-growing face and requires the knowledge of solute crystal face integration coefficients in both directions. A parameter estimation algorithm was derived to extract those coefficients from data about temporal concentration and crystal size during crystallization and was designed to have a short run time, while providing a high-resolution estimation. The model predicts a size-dependent growth rate and simulations indicated that for a given seed size and solvent system and for an isothermal anti-solvent addition crystallization, the seed loading and the supersaturation at seeding are the main factors impacting the final aspect ratio. The model predicts a decrease of the growth inhibition effect by the wrong conformer with increasing temperature, likely due to faster equilibration between conformers and/or a decrease of the population of the wrong conformer, if of low energy, at elevated temperatures. Finally, the model predicts that solute surface integration becomes the rate-limiting mechanism for high solute integration activation energies, resulting in no impact of the WC on the overall crystal growth process. [ABSTRACT FROM AUTHOR]

Methylphenylarsinic acid, MePhAsO·OH, a contaminant of rice plants and of groundwater, has been the subject of a single crystal X-ray study. In the crystal lattice the molecules form hydrogen-bonded chains linking O…HO entities; As-O, OH are 1.654(1), 1.719(1) Å. [ABSTRACT FROM AUTHOR]

A seventh blind test of crystal structure prediction has been organized by the Cambridge Crystallographic Data Centre. The results are presented in two parts, with this second part focusing on methods for ranking crystal structures in order of stability. The exercise involved standardized sets of structures seeded from a range of structure generation methods. Participants from 22 groups applied several periodic DFT-D methods, machine learned potentials, force fields derived from empirical data or quantum chemical calculations, and various combinations of the above. In addition, one non-energy-based scoring function was used. Results showed that periodic DFT-D methods overall agreed with experimental data within expected error margins, while one machine learned model, applying system-specific AIMnet potentials, agreed with experiment in many cases demonstrating promise as an efficient alternative to DFT-based methods. For target XXXII, a consensus was reached across periodic DFT methods, with consistently high predicted energies of experimental forms relative to the global minimum (above 4 kJ mol -1 at both low and ambient temperatures) suggesting a more stable polymorph is likely not yet observed. The calculation of free energies at ambient temperatures offered improvement of predictions only in some cases (for targets XXVII and XXXI). Several avenues for future research have been suggested, highlighting the need for greater efficiency considering the vast amounts of resources utilized in many cases., (open access.)

A seventh blind test of crystal structure prediction was organized by the Cambridge Crystallographic Data Centre featuring seven target systems of varying complexity: a silicon and iodine-containing molecule, a copper coordination complex, a near-rigid molecule, a cocrystal, a polymorphic small agrochemical, a highly flexible polymorphic drug candidate, and a polymorphic morpholine salt. In this first of two parts focusing on structure generation methods, many crystal structure prediction (CSP) methods performed well for the small but flexible agrochemical compound, successfully reproducing the experimentally observed crystal structures, while few groups were successful for the systems of higher complexity. A powder X-ray diffraction (PXRD) assisted exercise demonstrated the use of CSP in successfully determining a crystal structure from a low-quality PXRD pattern. The use of CSP in the prediction of likely cocrystal stoichiometry was also explored, demonstrating multiple possible approaches. Crystallographic disorder emerged as an important theme throughout the test as both a challenge for analysis and a major achievement where two groups blindly predicted the existence of disorder for the first time. Additionally, large-scale comparisons of the sets of predicted crystal structures also showed that some methods yield sets that largely contain the same crystal structures., (open access.)

Introduction: The objective of this study was to evaluate retinal sensitivity in subfields and its association with the novel quantitative contrast sensitivity function (qCSF) in patients with early age-related macular degeneration (eAMD), in patients with intermediate AMD (iAMD), and in healthy controls., Methods: In this prospective longitudinal study, retinal sensitivity of a customized 24-point grid was assessed by microperimetry Macular Integrity Assessment (MAIA, CenterVue, Padova, Italy) and divided into different subfields. The Multiple Contrast Vision Meter (Adaptive Sensory Technology, San Diego, CA, USA) was used for qCSF testing. Linear models were used to test the association of functional metrics with variables of interest., Results: 92 study eyes from 92 participants were analyzed (13 eAMD, 31 iAMD, and 48 controls). Microperimetry subfield comparison showed significant differences (p < 0.0001) in the control group between superior and inferior hemifield as well as between central and peripheral subfields. For eAMD, significant differences were found between central and peripheral subfields (p < 0.001) and specific subfields (p < 0.05) and finally for iAMD between specific quadrants (p < 0.05) and specific squares (p < 0.05). Significant associations of retinal sensitivity with qCSF metrics were found for the area underneath the logarithmic contrast sensitivity function, contrast acuity and for the contrast sensitivity at specific spatial frequencies., Conclusions: This study showed significant differences in the evaluated retinal sensitivity subfields, providing localized natural history data for retinal sensitivity in healthy controls and patients with eAMD and iAMD., (© 2024 The Author(s). Published by S. Karger AG, Basel.)

Purpose: The purpose of this study was to describe, validate, and compare the contrast sensitivity functions (CSFs) acquired with the novel quick CSF (qCSF) method from patients with early and intermediate age-related macular degeneration (eAMD and iAMD) and healthy controls., Methods: This is a cross-sectional analysis of contrast sensitivity (CS) and visual acuity (VA) baseline data from the prospective Multimodal Functional and Structural Visual System Characterization (MUMOVI) study. The qCSF testing was conducted with the manifold contrast vision meter (Adaptive Sensory Technology, San Diego, CA, USA). CS levels at spatial frequencies from 1 cycle per degree (CPD) to 18 CPD, the area underneath the logarithmic contrast sensitivity function (AULCSF), and contrast acuity (CA) were analyzed. The association of functional metrics with variables of interest was tested with linear models., Results: Ninety-four study eyes from 94 study patients were included in the analysis (13 patients with eAMD, 33 patients with iAMD, and 48 healthy controls). Significant differences between the eAMD and the iAMD model estimates were only found for CS at 1 CPD (t value = -2.9, P value = 0.006) and CS at 1.5 CPD (-2.7, 0.01). A specific association between smoking years and CS at 1 CPD (P = 0.02) and CS at 1.5 CPD (P = 0.03) could be described in patients with AMD., Conclusions: The qCSF testing allows the fast measurement of the whole CSF, enabling the integration into clinical routine. We showed that novel qCSF-derived metrics detect slight functional differences between AMD stages, which testing by Pelli-Robson charts or VA testing would miss. This study, therefore, yields novel qCSF-derived candidate metrics for therapeutic trials in AMD.

We have performed a comparison of the experimental thermal diffuse scattering (TDS) from crystalline Aspirin (form I) to that calculated from molecular dynamics (MD) simulations based on a variety of general force fields and a tailor-made force field (TMFF). A comparison is also made with Monte Carlo (MC) simulations which use a "harmonic network" approach to describe the intermolecular interactions. These comparisons were based on the hypothesis that TDS could be a useful experimental data in validation of such simulation parameter sets, especially when calculations of dynamical properties (e.g., thermodynamic free energies) from molecular crystals are concerned. Currently such a validation of force field parameters against experimental data is often limited to calculation of specific physical properties, e.g., absolute lattice energies usually at 0 K or heat capacity measurements. TDS harvested from in-house or synchrotron experiments comprises highly detailed structural information representative of the dynamical motions of the crystal lattice. Thus, TDS is a well-suited experimental data-driven means of cross validating theoretical approaches targeted at understanding dynamical properties of crystals. We found from the results of our investigation that the TMFF and COMPASS (from the commercial software "Materials Studio") parameter sets gave the best agreement with experiment. From our homologous MC simulation analysis we are able to show that force constants associated with the molecular torsion angles are likely to be a strong contributing factor for the apparent reason why these aforementioned force fields performed better.

Our understanding of the cardiorenal syndrome continues to progress. Decades of research have led to a better definition of the clinical cardiorenal syndrome and have laid the groundwork for understanding its pathophysiology. Although improvements have been made, there are still knowledge gaps concerning the interactions of these two organ systems. In the present review, we examine those interactions in the setting of acute and chronic cardiac decompensation and the resulting impacts on renal dysfunction. Recognition and prevention of this syndrome may help to better serve a growing patient population.

Omega-3 fatty acids are abundant in fish oil. A high dietary intake of omega-3 fatty acids has been strongly linked to lower rates of cardiovascular disease in epidemiologic studies. Fish oil supplements lower triglyceride levels and may have other benefits such as preventing arrhythmias, reducing inflammation (although they have minimal impact on C-reactive protein), inhibiting platelet aggregation, and lowering blood pressure, all of which should reduce cardiovascular risk.

The title compound, [La(C(6)H(2)N(3)O(7))(3)(C(2)H(6)O)(3)]·C(15)H(12)N(4), has two mol-ecular building blocks, namely the neutral mononuclear adduct of lanthanum picrate with ethanol [i.e. La(pic)(3):EtOH (1:3); La(pic)(3) = lanthanum picrate and EtOH = ethanol] and the oligodentate aromatic nitro-gen base tri-2-pyridylamine (tpa). The asymmetric unit contains two formula units. The compound was prepared during an investigation of the stereochemistry of lanthanoid picrate complexes with O-donor ligands. The metal-ligand adduct adopts a nine-coordinate tricapped trigonal-prismatic metal atom environment. The stereochemical arrangement of the ligands about the metal core is typical of a fac-isomer with stoichiometry M(bidentate)(3)(monodentate)(3). Face-to-face hydrogen bonds are found between the tpa mol-ecule and the ethanol ligands. One ethanol ligand is disordered over two positions, with site occupancy factors of ca 0.7 and 0.3. The oxygen atoms of a nitro group are also disordered over two positions; the site occupancy factors are ca 0.6 and 0.4.