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Crystal structure, Hirshfeld surface analysis, DFT and the mol­ecular docking studies of 3-(2-chloro­acet­yl)-2,4,6,8-tetra­phenyl-3,7-di­azabicyclo­[3.3.1]nonan-9-one

In the title compound, C33H29ClN2O2, the two piperidine rings of the di­aza­bicyclo moiety adopt distorted-chair conformations. Inter­molecular C—H⋯π inter­actions are mainly responsible for the crystal packing. The inter­molecular inter­actions were qu­anti­fied and analysed using Hirshfeld surface analysis, revealing that H⋯H inter­actions contribute most to the crystal packing (52.3%). The mol­ecular structure was further optimized by density functional theory (DFT) at the B3LYP/6–31 G(d,p) level and is compared with the experimentally determined mol­ecular structure in the solid state.




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Crystal structure, Hirshfeld surface analysis, DFT optimized mol­ecular structure and the mol­ecular docking studies of 1-[2-(cyano­sulfan­yl)acet­yl]-3-methyl-2,6-bis­(4-methyl­phen­yl)piperidin-4-one

The two mol­ecules in the asymmetric unit of the title compound, C23H24N2O2S, have a structural overlap with an r.m.s. deviation of 0.82 Å. The piperidine rings adopt a distorted boat conformation. Intra- and inter­molecular C—H⋯O hydrogen bonds are responsible for the cohesion of the crystal packing. The inter­molecular inter­actions were qu­anti­fied and analysed using Hirshfeld surface analysis. The mol­ecular structure optimized by density functional theory (DFT) at the B3LYP/6–311++G(d,p)level is compared with the experimentally determined mol­ecular structure in the solid state.




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Synthesis, crystal structure, and Hirshfeld surface analysis of 1,3-di­hydro-2H-benzimidazol-2-iminium 3-carb­oxy-4-hy­droxy­benzene­sulfonate

The asymmetric unit of the title salt, C7H8N3+·C7H5O6S−, comprises two 1,3-di­hydro-2H-benzimidazol-2-iminium cations and two 2-hy­droxy-5-sulfobenzoate anions (Z' = 2). In the crystal, the mol­ecules inter­act through N—H⋯O, O—H⋯O hydrogen bonds and C—O⋯π contacts. The hydrogen-bonding inter­actions lead to the formation of layers parallel to (overline{1}01). Hirshfeld surface analysis revealed that H⋯H contacts contribute to most of the crystal packing with 38.9%, followed by H⋯O contacts with 36.2%.




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Crystal structure, Hirshfeld surface analysis, and calculations of inter­molecular inter­action energies and energy frameworks of 1-[(1-hexyl-1H-1,2,3-triazol-4-yl)meth­yl]-3-(1-methyl­ethen­yl)-benzimidazol-2-one

The benzimidazole moiety in the title mol­ecule, C19H25N5O, is almost planar and oriented nearly perpendicular to the triazole ring. In the crystal, C—H⋯O hydrogen bonds link the mol­ecules into a network structure. There are no π–π inter­actions present but two weak C—H⋯π(ring) inter­actions are observed. A Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (62.0%), H⋯C/C⋯H (16.1%), H⋯N/N⋯H (13.7%) and H⋯O/O⋯H (7.5%) inter­actions. Evaluation of the electrostatic, dispersion and total energy frameworks indicate that the stabilization is dominated via the dispersion energy contributions in the title compound.




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Mol­ecular structure of tris­[(6-bromo­pyridin-2-yl)meth­yl]amine

Coordination compounds of polydentate nitro­gen ligands with metals are used extensively in research areas such as catalysis, and as models of complex active sites of enzymes in bioinorganic chemistry. Tris(2-pyridyl­meth­yl)amine (TPA) is a tripodal tetra­dentate ligand that is known to form coordination compounds with metals, including copper, iron and zinc. The related compound, tris­[(6-bromo­pyridin-2-yl)meth­yl]amine (TPABr3), C18H15Br3N4, which possesses a bromine atom on the 6-position of each of the three pyridyl moieties, is also known but has not been heavily investigated. The mol­ecular structure of TPABr3 as determined by X-ray diffraction is reported here. The TPABr3 molecule belongs to the triclinic, Poverline{1} space group and displays interesting intermolecular Br⋯Br interactions that provide a stabilizing influence within the molecule.




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Crystal structure and Hirshfeld surface analysis of (E)-N-(2-styrylphen­yl)benzene­sulfonamide

The crystal structure of the title compound C20H17NO2S features hydrogen-bonding and C—H⋯π inter­actions. Hirshfeld surface analysis revealed that H⋯H, C⋯H/H⋯C and O⋯H/H⋯O inter­actions make a major contribution to the crystal packing. Docking studies were carried out to determine the binding affinity and inter­action profile of the title compound with EGFR kinase, a member of the ErbB family of receptor tyrosine kinases, which is crucial for processes such as cell proliferation and differentiation. The title compound shows a strong binding affinity with EGFR kinase, with the most favourable conformation having a binding energy of −8.27 kcal mol−1 and a predicted IC50 of 870.34 nM, indicating its potential as a promising candidate for targeted lung cancer therapy.




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Synthesis, crystal structure and Hirshfeld surface analysis of sulfamethoxazolium methyl­sulfate monohydrate

The mol­ecular salt sulfamethoxazolium {or 4-[(5-methyl-1,2-oxazol-3-yl)sulf­amo­yl]anilinium methyl sulfate monohydrate}, C10H12N3O3S+·CH3O4S−·H2O, was prepared by the reaction of sulfamethoxazole and H2SO4 in methanol and crystallized from methanol–ether–water. Protonation takes place at the nitro­gen atom of the primary amino group. In the crystal, N—H⋯O hydrogen bonds (water and methyl­sulfate anion) and inter­molecular N—H⋯N inter­actions involving the sulfonamide and isoxazole nitro­gen atoms, link the components into a tri-dimensional network, additional cohesion being provided by face-to-face π–π inter­actions between the phenyl rings of adjacent mol­ecules. A Hirshfeld surface analysis was used to verify the contributions of the different inter­molecular inter­actions, showing that the three most important contributions for the crystal packing are from H⋯O (54.1%), H⋯H (29.2%) and H⋯N (5.0%) inter­actions.




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Crystal structure and Hirshfeld surface analyses, crystal voids, inter­molecular inter­action energies and energy frameworks of 3-benzyl-1-(3-bromoprop­yl)-5,5-di­phenyl­imidazolidine-2,4-dione

The title mol­ecule, C25H23BrN2O2, adopts a cup shaped conformation with the distinctly ruffled imidazolidine ring as the base. In the crystal, weak C—H⋯O hydrogen bonds and C—H⋯π(ring) inter­actions form helical chains of mol­ecules extending along the b-axis direction that are linked by additional weak C—H⋯π(ring) inter­actions across inversion centres. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (51.0%), C⋯H/H⋯C (21.3%), Br⋯H/H⋯Br (12.8%) and O⋯H/H⋯O (12.4%) inter­actions. The volume of the crystal voids and the percentage of free space were calculated to be 251.24 Å3 and 11.71%, respectively, showing that there is no large cavity in the crystal packing. Evaluation of the electrostatic, dispersion and total energy frameworks indicate that the stabilization is dominated by the dispersion energy.




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Crystal structure and supra­molecular features of a host–guest inclusion complex based on A1/A2-hetero-difunctionalized pillar[5]arene

A host–guest supra­molecular inclusion complex was obtained from the co-crystallization of A1/A2-bromo­but­oxy-hy­droxy difunctionalized pillar[5]arene (PilButBrOH) with adipo­nitrile (ADN), C47H53.18Br0.82O10·C6H8N2. The adipo­nitrile guest is stabilized within the electron-rich cavity of the pillar[5]arene host via multiple C—H⋯O and C—H⋯π inter­actions. Both functional groups on the macrocyclic rim are engaged in supra­molecular inter­actions with an adjacent inclusion complex via hydrogen-bonding (O—H⋯N or C—H⋯Br) inter­actions, resulting in the formation of a supra­molecular dimer in the crystal structure.




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The crystal structures determination and Hirshfeld surface analysis of N-(4-bromo-3-meth­oxy­phen­yl)- and N-{[3-bromo-1-(phenyl­sulfon­yl)-1H-indol-2-yl]meth­yl}- derivatives of N-{[3-bromo-1-(phenylsulfon­yl)-1H-indol-

Two new phenyl­sulfonyl­indole derivatives, namely, N-{[3-bromo-1-(phenyl­sulfon­yl)-1H-indol-2-yl]meth­yl}-N-(4-bromo-3-meth­oxy­phen­yl)benzene­sulfonamide, C28H22Br2N2O5S2, (I), and N,N-bis­{[3-bromo-1-(phenyl­sulfon­yl)-1H-indol-2-yl]meth­yl}benzene­sulfonamide, C36H27Br2N3O6S3, (II), reveal the impact of intra­molecular π–π inter­actions of the indole moieties as a factor not only governing the conformation of N,N-bis­(1H-indol-2-yl)meth­yl)amines, but also significantly influencing the crystal patterns. For I, the crystal packing is dominated by C—H⋯π and π–π bonding, with a particular significance of mutual indole–indole inter­actions. In the case of II, the mol­ecules adopt short intra­molecular π–π inter­actions between two nearly parallel indole ring systems [with the centroids of their pyrrole rings separated by 3.267 (2) Å] accompanied by a set of forced Br⋯O contacts. This provides suppression of similar inter­actions between the mol­ecules, while the importance of weak C—H⋯O hydrogen bonding to the packing naturally increases. Short contacts of the latter type [C⋯O = 3.389 (6) Å] assemble pairs of mol­ecules into centrosymmetric dimers with a cyclic R22(13) ring motif. These findings are consistent with the results of a Hirshfeld surface analysis and together they suggest a tool for modulating the supra­molecular behavior of phenyl­sulfonyl­ated indoles.




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Crystal structures of two different multi-component crystals consisting of 1-(3,4-di­meth­oxy­benz­yl)-6,7-di­meth­oxy­iso­quinoline and fumaric acid

Two different multi-component crystals consisting of papaverine [1-(3,4-di­meth­oxy­benz­yl)-6,7-di­meth­oxy­iso­quinoline, C20H21NO4] and fumaric acid [C4H4O4] were obtained. Single-crystal X-ray structure analysis revealed that one, C20H21NO4·1.5C4H4O4 (I), is a salt co-crystal composed of salt-forming and non-salt-forming mol­ecules, and the other, C20H21NO4·0.5C4H4O4 (II), is a salt–co-crystal inter­mediate (i.e., in an inter­mediate state between a salt and a co-crystal). In this study, one state (crystal structure at 100 K) within the salt–co-crystal continuum is defined as the ‘inter­mediate’.




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Crystal structure, Hirshfeld surface analysis, and DFT and mol­ecular docking studies of 6-cyanona­phthalen-2-yl 4-(benz­yloxy)benzoate

In the title compound, C25H17NO3, the torsion angle associated with the phenyl benzoate group is −173.7 (2)° and that for the benz­yloxy group is −174.8 (2)° establishing an anti-type conformation. The dihedral angles between the ten-membered cyanona­phthalene ring and the aromatic ring of the phenyl benzoate and the benz­yloxy fragments are 40.70 (10) and 87.51 (11)°, respectively, whereas the dihedral angle between the aromatic phenyl benzoate and the benz­yloxy fragments is 72.30 (13)°. In the crystal, the mol­ecules are linked by weak C—H⋯O inter­actions forming S(4) chains propagating parallel to [010]. The packing is consolidated by three C—H⋯π inter­actions and two π–π stacking inter­actions between the aromatic rings of naphthalene and phenyl benzoate with centroid-to-centroid distances of 3.9698 (15) and 3.8568 (15) Å, respectively. Inter­molecular inter­actions were qu­anti­fied using Hirshfeld surface analysis. The mol­ecular structure was further optimized by density functional theory (DFT) at the B3LYP/6–311+ G(d,p) level, revealing that the energy gap between HOMO and LUMO is 3.17 eV. Mol­ecular docking studies were carried out for the title compound as a ligand and SARS-Covid-2(PDB ID:7QF0) protein as a receptor giving a binding affinity of −9.5 kcal mol−1.




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Structural multiplicity in a solvated hydrate of the anti­retroviral protease inhibitor Lopinavir

Lopinavir is a potent protease inhibitor that is used as a first-line pharmaceutical drug for the treatment of HIV. The multi-component solvated Lopinavir crystal, systematic name (2S)-N-[(2S,4S,5S)-5-[2-(2,6-di­methyl­phen­oxy)acetamido]-4-hy­droxy-1,6-di­phenyl­hexan-2-yl]-3-methyl-2-(2-oxo-1,3-diazinan-1-yl)butanamide–ethane-1,2-diol–water (8/3/7) 8C37H48N4O5·3C2H6O2·7H2O, was prepared using evaporative methods. The crystalline material obtained from this experimental synthesis was characterized and elucidated by single-crystal X-ray diffraction (SC-XRD). The crystal structure is unusual in that the unit cell contains 18 mol­ecules. The stoichiometric ratio of this crystal is eight Lopinavir mol­ecules [8(C37H48N4O5)], three ethane-1,2-diol mol­ecules [3(C2H6O2)] and seven water mol­ecules [7(H2O)]. The crystal packing features both bi- and trifurcated hydrogen bonds between atoms.




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Multi-segment cooling design of a reflection mirror based on the finite-element method

Through numerical optimization of cooling lengths and cooling groove positions for the first reflection mirror of a free-electron laser [OK?], the root mean square of the height error of the mirror's thermal deformation was minimized. The optimized mirror design effectively mitigated stray light and enhanced the peak intensity of the focus spot at the sample, thereby enhancing the optical performance of the high-heat-load mirror under high repetition rates at beamline FEL-II of the SHINE facility.




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Time-resolved high-energy X-ray diffraction studies of ultrathin Ni ferrite films on MgO(001)

Time-resolved high-energy X-ray diffraction was used during growth of ultrathin NixFe3−xO4 films with varying Ni content (0 ≤ x ≤ 1.5) deposited on MgO(001) substrates by reactive molecular beam epitaxy, providing an insight into the growth dynamics of these films. In order to obtain structural information, reciprocal-space maps were recorded and the temporal evolution of the Bragg peaks specific to the octahedral and tetrahedral lattice sites of the inverse spinel structure of NixFe3−xO4 was observed during growth of the films. A time delay, corresponding to a coverage of 1.2–1.8 nm, between the appearance of the Bragg reflections originating from octahedral sites and reflections originating exclusively from tetrahedral sites indicates that the ferrite films grow in two stages. In the initial growth phase, a rock salt interface layer is formed. Afterwards, a structural transition occurs and the films grow in an inverse spinel structure. The thickness of the initial rock salt phase was found to increase with Ni content and to be responsible for atypical strain in the thin films. Films with Ni contents x > 1 do not show a structural transition. These films remain in a (deficient) rock salt structure consisting of a mixed Ni–Fe oxide and do not form a spinel structure at all. They show an increased number of NiO clusters as detected by X-ray photoelectron spectroscopy of the valence band, accompanied by a significant roughening of the films.




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Van Vleck analysis of angularly distorted octahedra using VanVleckCalculator

Van Vleck modes describe all possible displacements of octahedrally coordinated ligands about a core atom. They are a useful analytical tool for analysing the distortion of octahedra, particularly for first-order Jahn–Teller distortions, but determination of the Van Vleck modes of an octahedron is complicated by the presence of angular distortion of the octahedron. This problem is most commonly resolved by calculating the bond distortion modes (Q2, Q3) along the bond axes of the octahedron, disregarding the angular distortion and losing information on the octahedral shear modes (Q4, Q5 and Q6) in the process. In this paper, the validity of assuming bond lengths to be orthogonal in order to calculate the Van Vleck modes is discussed, and a method is described for calculating Van Vleck modes without disregarding the angular distortion. A Python package for doing this, VanVleckCalculator, is introduced and some examples of its use are given. Finally, it is shown that octahedral shear and angular distortion are often, but not always, correlated, and a parameter η is proposed as the shear fraction. It is demonstrated that η can be used to predict whether the values will be correlated when varying a tuning parameter such as temperature or pressure.




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Fast nanoscale imaging of strain in a multi-segment heterostructured nanowire with 2D Bragg ptychography

Developing semiconductor devices requires a fast and reliable source of strain information with high spatial resolution and strain sensitivity. This work investigates the strain in an axially heterostructured 180 nm-diameter GaInP nanowire with InP segments of varying lengths down to 9 nm, simultaneously probing both materials. Scanning X-ray diffraction (XRD) is compared with Bragg projection ptychography (BPP), a fast single-projection method. BPP offers a sufficient spatial resolution to reveal fine details within the largest segments, unlike scanning XRD. The spatial resolution affects the quantitative accuracy of the strain maps, where BPP shows much-improved agreement with an elastic 3D finite element model compared with scanning XRD. The sensitivity of BPP to small deviations from the Bragg condition is systematically investigated. The experimental confirmation of the model suggests that the large lattice mismatch of 1.52% is accommodated without defects.




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Convolutional neural network approach for the automated identification of in cellulo crystals

In cellulo crystallization is a rare event in nature. Recent advances that have made use of heterologous overexpression can promote the intracellular formation of protein crystals, but new tools are required to detect and characterize these targets in the complex cell environment. The present work makes use of Mask R-CNN, a convolutional neural network (CNN)-based instance segmentation method, for the identification of either single or multi-shaped crystals growing in living insect cells, using conventional bright field images. The algorithm can be rapidly adapted to recognize different targets, with the aim of extracting relevant information to support a semi-automated screening pipeline, in order to aid the development of the intracellular protein crystallization approach.




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The multi-slit very small angle neutron scattering instrument at the China Spallation Neutron Source

A multi-slit very small angle neutron scattering (MS-VSANS) instrument has been finally accepted at the China Spallation Neutron Source (CSNS). It is the first spallation neutron source based VSANS instrument. MS-VSANS has a good signal-to-noise ratio and can cover a wide scattering vector magnitude range from 0.00028 to 1.4 Å−1. In its primary flight path, a combined curved multichannel beam bender and sections of rotary exchange drums are installed to minimize the background downstream of the instrument. An exchangeable multi-slit beam focusing system is integrated into the primary flight path, enabling access to a minimum scattering vector magnitude of 0.00028 Å−1. MS-VSANS has three modes, namely conventional SANS, polarizing SANS and VSANS modes. In the SANS mode, three motorized high-efficiency 3He tube detectors inside the detector tank cover scattering angles from 0.12 to 35° simultaneously. In the polarizing SANS mode, a double-V cavity provides highly polarized neutrons and a high-efficiency 3He polarization analyser allows full polarization analysis. In the VSANS mode, an innovative high-resolution gas electron multiplier detector covers scattering angles from 0.016 to 0.447°. The absolute scattering intensities of a selection of standard samples are obtained using the direct-beam technique; the effectiveness of this method is verified by testing the standard samples and comparing the results with those from a benchmark instrument. The MS-VSANS instrument is designed to be flexible and versatile and all the design goals have been achieved.




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X-Ray Calc 3: improved software for simulation and inverse problem solving for X-ray reflectivity

This work introduces X-Ray Calc (XRC), an open-source software package designed to simulate X-ray reflectivity (XRR) and address the inverse problem of reconstructing film structures on the basis of measured XRR curves. XRC features a user-friendly graphical interface that facilitates interactive simulation and reconstruction. The software employs a recursive approach based on the Fresnel equations to calculate XRR and incorporates specialized tools for modeling periodic multilayer structures. This article presents the latest version of the X-Ray Calc software (XRC3), with notable improvements. These enhancements encompass an automatic fitting capability for XRR curves utilizing a modified flight particle swarm optimization algorithm. A novel cost function was also developed specifically for fitting XRR curves of periodic structures. Furthermore, the overall user experience has been enhanced by developing a new single-window interface.




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Simulations of dislocation contrast in dark-field X-ray microscopy

Dark-field X-ray microscopy (DFXM) is a full-field imaging technique that non-destructively maps the structure and local strain inside deeply embedded crystalline elements in three dimensions. In DFXM, an objective lens is placed along the diffracted beam to generate a magnified projection image of the local diffracted volume. This work explores contrast methods and optimizes the DFXM setup specifically for the case of mapping dislocations. Forward projections of detector images are generated using two complementary simulation tools based on geometrical optics and wavefront propagation, respectively. Weak and strong beam contrast and the mapping of strain components are studied. The feasibility of observing dislocations in a wall is elucidated as a function of the distance between neighbouring dislocations and the spatial resolution. Dislocation studies should be feasible with energy band widths of 10−2, of relevance for fourth-generation synchrotron and X-ray free-electron laser sources.




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FLEXR GUI: a graphical user interface for multi-conformer modeling of proteins

Proteins are well known `shapeshifters' which change conformation to function. In crystallography, multiple conformational states are often present within the crystal and the resulting electron-density map. Yet, explicitly incorporating alternative states into models to disentangle multi-conformer ensembles is challenging. We previously reported the tool FLEXR, which, within a few minutes, automatically separates conformational signal from noise and builds the corresponding, often missing, structural features into a multi-conformer model. To make the method widely accessible for routine multi-conformer building as part of the computational toolkit for macromolecular crystallography, we present a graphical user interface (GUI) for FLEXR, designed as a plugin for Coot 1. The GUI implementation seamlessly connects FLEXR models with the existing suite of validation and modeling tools available in Coot. We envision that FLEXR will aid crystallographers by increasing access to a multi-conformer modeling method that will ultimately lead to a better representation of protein conformational heterogeneity in the Protein Data Bank. In turn, deeper insights into the protein conformational landscape may inform biology or provide new opportunities for ligand design. The code is open source and freely available on GitHub at https://github.com/TheFischerLab/FLEXR-GUI.




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A correction procedure for secondary scattering contributions from windows in small-angle X-ray scattering and ultra-small-angle X-ray scattering

This article describes a correction procedure for the removal of indirect background contributions to measured small-angle X-ray scattering patterns. The high scattering power of a sample in the ultra-small-angle region may serve as a secondary source for a window placed in front of the detector. The resulting secondary scattering appears as a sample-dependent background in the measured pattern that cannot be directly subtracted. This is an intricate problem in measurements at ultra-low angles, which can significantly reduce the useful dynamic range of detection. Two different procedures are presented to retrieve the real scattering profile of the sample.




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Reconstructing the reflectivity of liquid surfaces from grazing incidence X-ray off-specular scattering data

The capillary wave model of a liquid surface predicts both the X-ray specular reflection and the diffuse scattering around it. A quantitative method is presented to obtain the X-ray reflectivity (XRR) from a liquid surface through the diffuse scattering data around the specular reflection measured using a grazing incidence X-ray off-specular scattering (GIXOS) geometry at a fixed horizontal offset angle with respect to the plane of incidence. With this approach the entire Qz-dependent reflectivity profile can be obtained at a single, fixed incident angle. This permits a much faster acquisition of the profile than with conventional reflectometry, where the incident angle must be scanned point by point to obtain a Qz-dependent profile. The XRR derived from the GIXOS-measured diffuse scattering, referred to in this paper as pseudo-reflectivity, provides a larger Qz range compared with the reflectivity measured by conventional reflectometry. Transforming the GIXOS-measured diffuse scattering profile to pseudo-XRR opens up the GIXOS method to widely available specular XRR analysis software tools. Here the GIXOS-derived pseudo-XRR is compared with the XRR measured by specular reflectometry from two simple vapor–liquid interfaces at different surface tension, and from a hexadecyltri­methyl­ammonium bromide monolayer on a water surface. For the simple liquids, excellent agreement (beyond 11 orders of magnitude in signal) is found between the two methods, supporting the approach of using GIXOS-measured diffuse scattering to derive reflectivities. Pseudo-XRR obtained at different horizontal offset angles with respect to the plane of incidence yields indistinguishable results, and this supports the robustness of the GIXOS-XRR approach. The pseudo-XRR method can be extended to soft thin films on a liquid surface, and criteria are established for the applicability of the approach.




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Phase-contrast neutron imaging compared with wave propagation and McStas simulations

Propagation-based phase contrast, for example in the form of edge enhancement contrast, is well established within X-ray imaging but is not widely used in neutron imaging. This technique can help increase the contrast of low-attenuation samples but may confuse quantitative absorption measurements. Therefore, it is important to understand the experimental parameters that cause and amplify or dampen this effect in order to optimize future experiments properly. Two simulation approaches have been investigated, a wave-based simulation and a particle-based simulation conducted in McStas [Willendrup & Lefmann (2020). J. Neutron Res. 22, 1–16], and they are compared with experimental data. The experiment was done on a sample of metal foils with weakly and strongly neutron absorbing layers, which were measured while varying the rotation angle and propagation distance from the sample. The experimental data show multiple signals: attenuation, phase contrast and reflection. The wave model reproduces the sample attenuation and the phase peaks but it does not reproduce the behavior of these peaks as a function of rotation angle. The McStas simulation agrees better with the experimental data, as it reproduces attenuation, phase peaks and reflection, as well as the change in these signals as a function of rotation angle and distance. This suggests that the McStas simulation approach, where the particle description of the neutron facilitates the incorporation of multiple effects, is the most convenient way of modeling edge enhancement in neutron imaging.




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Neural networks for rapid phase quantification of cultural heritage X-ray powder diffraction data

Recent developments in synchrotron radiation facilities have increased the amount of data generated during acquisitions considerably, requiring fast and efficient data processing techniques. Here, the application of dense neural networks (DNNs) to data treatment of X-ray diffraction computed tomography (XRD-CT) experiments is presented. Processing involves mapping the phases in a tomographic slice by predicting the phase fraction in each individual pixel. DNNs were trained on sets of calculated XRD patterns generated using a Python algorithm developed in-house. An initial Rietveld refinement of the tomographic slice sum pattern provides additional information (peak widths and integrated intensities for each phase) to improve the generation of simulated patterns and make them closer to real data. A grid search was used to optimize the network architecture and demonstrated that a single fully connected dense layer was sufficient to accurately determine phase proportions. This DNN was used on the XRD-CT acquisition of a mock-up and a historical sample of highly heterogeneous multi-layered decoration of a late medieval statue, called `applied brocade'. The phase maps predicted by the DNN were in good agreement with other methods, such as non-negative matrix factorization and serial Rietveld refinements performed with TOPAS, and outperformed them in terms of speed and efficiency. The method was evaluated by regenerating experimental patterns from predictions and using the R-weighted profile as the agreement factor. This assessment allowed us to confirm the accuracy of the results.




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RMCProfile7: reverse Monte Carlo for multiphase systems

This work introduces a completely rewritten version of the program RMCProfile (version 7), big-box, reverse Monte Carlo modelling software for analysis of total scattering data. The major new feature of RMCProfile7 is the ability to refine multiple phases simultaneously, which is relevant for many current research areas such as energy materials, catalysis and engineering. Other new features include improved support for molecular potentials and rigid-body refinements, as well as multiple different data sets. An empirical resolution correction and calculation of the pair distribution function as a back-Fourier transform are now also available. RMCProfile7 is freely available for download at https://rmcprofile.ornl.gov/.




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Quality assessment of the wide-angle detection option planned at the high-intensity/extended Q-range SANS diffractometer KWS-2 combining experiments and McStas simulations

For a reliable characterization of materials and systems featuring multiple structural levels, a broad length scale from a few ångström to hundreds of nanometres must be analyzed and an extended Q range must be covered in X-ray and neutron scattering experiments. For certain samples or effects, it is advantageous to perform such characterization with a single instrument. Neutrons offer the unique advantage of contrast variation and matching by D-labeling, which is of great value in the characterization of natural or synthetic polymers. Some time-of-flight small-angle neutron scattering (TOF-SANS) instruments at neutron spallation sources can cover an extended Q range by using a broad wavelength band and a multitude of detectors. The detectors are arranged to cover a wide range of scattering angles with a resolution that allows both large-scale morphology and crystalline structure to be resolved simultaneously. However, for such analyses, the SANS instruments at steady-state sources operating in conventional monochromatic pinhole mode rely on additional wide-angle neutron scattering (WANS) detectors. The resolution must be tuned via a system of choppers and a TOF data acquisition option to reliably measure the atomic to mesoscale structures. The KWS-2 SANS diffractometer at Jülich Centre for Neutron Science allows the exploration of a wide Q range using conventional pinhole and lens focusing modes and an adjustable resolution Δλ/λ between 2 and 20%. This is achieved through the use of a versatile mechanical velocity selector combined with a variable slit opening and rotation frequency chopper. The installation of WANS detectors planned on the instrument required a detailed analysis of the quality of the data measured over a wide angular range with variable resolution. This article presents an assessment of the WANS performance by comparison with a McStas [Willendrup, Farhi & Lefmann (2004). Physica B, 350, E735–E737] simulation of ideal experimental conditions at the instrument.




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On the feasibility of time-resolved X-ray powder diffraction of macromolecules using laser-driven ultrafast X-ray sources

With the emergence of ultrafast X-ray sources, interest in following fast processes in small molecules and macromolecules has increased. Most of the current research into ultrafast structural dynamics of macromolecules uses X-ray free-electron lasers. In parallel, small-scale laboratory-based laser-driven ultrafast X-ray sources are emerging. Continuous development of these sources is underway, and as a result many exciting applications are being reported. However, because of their low flux, such sources are not commonly used to study the structural dynamics of macromolecules. This article examines the feasibility of time-resolved powder diffraction of macromolecular microcrystals using a laboratory-scale laser-driven ultrafast X-ray source.




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Practical courses on advanced methods in macromolecular crystallization: 20 years of history and future perspectives

The first Federation of European Biochemical Societies Advanced Course on macromolecular crystallization was launched in the Czech Republic in October 2004. Over the past two decades, the course has developed into a distinguished event, attracting students, early career postdoctoral researchers and lecturers. The course topics include protein purification, characterization and crystallization, covering the latest advances in the field of structural biology. The many hands-on practical exercises enable a close interaction between students and teachers and offer the opportunity for students to crystallize their own proteins. The course has a broad and lasting impact on the scientific community as participants return to their home laboratories and act as nuclei by communicating and implementing their newly acquired knowledge and skills.




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Coordinate-based simulation of pair distance distribution functions for small and large molecular assemblies: implementation and applications

X-ray scattering has become a major tool in the structural characterization of nanoscale materials. Thanks to the widely available experimental and computational atomic models, coordinate-based X-ray scattering simulation has played a crucial role in data interpretation in the past two decades. However, simulation of real-space pair distance distribution functions (PDDFs) from small- and wide-angle X-ray scattering, SAXS/WAXS, has been relatively less exploited. This study presents a comparison of PDDF simulation methods, which are applied to molecular structures that range in size from β-cyclo­dextrin [1 kDa molecular weight (MW), 66 non-hydrogen atoms] to the satellite tobacco mosaic virus capsid (1.1 MDa MW, 81 960 non-hydrogen atoms). The results demonstrate the power of interpretation of experimental SAXS/WAXS from the real-space view, particularly by providing a more intuitive method for understanding of partial structure contributions. Furthermore, the computational efficiency of PDDF simulation algorithms makes them attractive as approaches for the analysis of large nanoscale materials and biological assemblies. The simulation methods demonstrated in this article have been implemented in stand-alone software, SolX 3.0, which is available to download from https://12idb.xray.aps.anl.gov/solx.html.




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Multidimensional Rietveld refinement of high-pressure neutron diffraction data of PbNCN

High-pressure neutron powder diffraction data from PbNCN were collected on the high-pressure diffraction beamline SNAP located at the Spallation Neutron Source (SNS) of Oak Ridge National Laboratory (Tennessee, USA). The diffraction data were analyzed using the novel method of multidimensional (two dimensions for now, potentially more in the future) Rietveld refinement and, for comparison, employing the conventional Rietveld method. To achieve two-dimensional analysis, a detailed description of the SNAP instrument characteristics was created, serving as an instrument parameter file, and then yielding both cell and spatial parameters as refined under pressure for the first time for solid-state cyanamides/carbodi­imides. The bulk modulus B0 = 25.1 (15) GPa and its derivative B'0 = 11.1 (8) were extracted for PbNCN following the Vinet equation of state. Surprisingly, an internal transition was observed beyond 2.0 (2) GPa, resulting from switching the bond multiplicities (and bending direction) of the NCN2− complex anion. The results were corroborated using electronic structure calculation from first principles, highlighting both local structural and chemical bonding details.




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Towards dynamically configured databases for CIFs: the new modulated structures open database at the Bilbao Crystallographic Server

This article presents a web-based framework to build a database without in-depth programming knowledge given a set of CIF dictionaries and a collection of CIFs. The framework consists of two main elements: the public site that displays the information contained in the CIFs in an ordered manner, and the restricted administrative site which defines how that information is stored, processed and, eventually, displayed. Thus, the web application allows users to easily explore, filter and access the data, download the original CIFs, and visualize the structures via JSmol. The modulated structures open database B-IncStrDB, the official International Union of Crystallography repository for this type of material and available through the Bilbao Crystallographic Server, has been re-implemented following the proposed framework.




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Pinhole small-angle neutron scattering based approach for desmearing slit ultra-small-angle neutron scattering data

Presented here is an effective approach to desmearing slit ultra-small-angle neutron scattering (USANS) data, based on complementary small-angle neutron scattering (SANS) measurements, leading to a seamless merging of these data sets. The study focuses on the methodological aspects of desmearing USANS data, which can then be presented in the conventional manner of SANS, enabling a broader pool of data analysis methods. The key innovation lies in the use of smeared SANS data for extrapolating slit USANS, offering a self-consistent integrand function for desmearing with Lake's iterative method. The proposed approach is validated through experimental data on porous anodized aluminium oxide membranes, showcasing its applicability and benefits. The findings emphasize the importance of accurate desmearing for merging USANS and SANS data in the crossover q region, which is particularly crucial for complex scattering patterns.




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VMXm – A sub-micron focus macromolecular crystallography beamline at Diamond Light Source

VMXm joins the suite of operational macromolecular crystallography beamlines at Diamond Light Source. It has been designed to optimize rotation data collections from protein crystals less than 10 µm and down to below 1 µm in size. The beamline has a fully focused beam of 0.3 × 2.3 µm (vertical × horizontal) with a tuneable energy range (6–28 keV) and high flux (1.6 × 1012 photons s−1 at 12.5 keV). The crystals are housed within a vacuum chamber to minimize background scatter from air. Crystals are plunge-cooled on cryo-electron microscopy grids, allowing much of the liquid surrounding the crystals to be removed. These factors improve the signal-to-noise during data collection and the lifetime of the microcrystals can be prolonged by exploiting photoelectron escape. A novel in vacuo sample environment has been designed which also houses a scanning electron microscope to aid with sample visualization. This combination of features at VMXm allows measurements at the physical limits of X-ray crystallography on biomacromolecules to be explored and exploited.




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Development of crystal optics for X-ray multi-projection imaging for synchrotron and XFEL sources

X-ray multi-projection imaging (XMPI) is an emerging experimental technique for the acquisition of rotation-free, time-resolved, volumetric information on stochastic processes. The technique is developed for high-brilliance light-source facilities, aiming to address known limitations of state-of-the-art imaging methods in the acquisition of 4D sample information, linked to their need for sample rotation. XMPI relies on a beam-splitting scheme, that illuminates a sample from multiple, angularly spaced viewpoints, and employs fast, indirect, X-ray imaging detectors for the collection of the data. This approach enables studies of previously inaccessible phenomena of industrial and societal relevance such as fractures in solids, propagation of shock waves, laser-based 3D printing, or even fast processes in the biological domain. In this work, we discuss in detail the beam-splitting scheme of XMPI. More specifically, we explore the relevant properties of X-ray splitter optics for their use in XMPI schemes, both at synchrotron insertion devices and XFEL facilities. Furthermore, we describe two distinct XMPI schemes, designed to faciliate large samples and complex sample environments. Finally, we present experimental proof of the feasibility of MHz-rate XMPI at the European XFEL. This detailed overview aims to state the challenges and the potential of XMPI and act as a stepping stone for future development of the technique.




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Formulation of perfect-crystal diffraction from Takagi–Taupin equations: numerical implementation in the crystalpy library

The Takagi–Taupin equations are solved in their simplest form (zero deformation) to obtain the Bragg-diffracted and transmitted complex amplitudes. The case of plane-parallel crystal plates is discussed using a matrix model. The equations are implemented in an open-source Python library crystalpy adapted for numerical applications such as crystal reflectivity calculations and ray tracing.




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Synchrotron CT dosimetry for wiggler operation at reduced magnetic field and spatial modulation with bow tie filters

The Australian Synchrotron Imaging and Medical Beamline (IMBL) uses a superconducting multipole wiggler (SCMPW) source, dual crystal Laue monochromator and 135 m propagation distance to enable imaging and computed tomography (CT) studies of large samples with mono-energetic radiation. This study aimed to quantify two methods for CT dose reduction: wiggler source operation at reduced magnetic field strength, and beam modulation with spatial filters placed upstream from the sample. Transmission measurements with copper were used to indirectly quantify the influence of third harmonic radiation. Operation at lower wiggler magnetic field strength reduces dose rates by an order of magnitude, and suppresses the influence of harmonic radiation, which is of significance near 30 keV. Beam shaping filters modulate the incident beam profile for near constant transmitted signal, and offer protection to radio-sensitive surface organs: the eye lens, thyroid and female breast. Their effect is to reduce the peripheral dose and the dose to the scanned volume by about 10% for biological samples of 35–50 mm diameter and by 20–30% for samples of up to 160 mm diameter. CT dosimetry results are presented as in-air measurements that are specific to the IMBL, and as ratios to in-air measurements that may be applied to other beamlines. As CT dose calculators for small animals are yet to be developed, results presented here and in a previous study may be used to estimate absorbed dose to organs near the surface and the isocentre.




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Green upgrading of SPring-8 to produce stable, ultrabrilliant hard X-ray beams

SPring-8-II is a major upgrade project of SPring-8 that was inaugurated in October 1997 as a third-generation synchrotron radiation light source. This upgrade project aims to achieve three goals simultaneously: achievement of excellent light source performance, refurbishment of aged systems, and significant reduction in power consumption for the entire facility. A small emittance of 50 pm rad will be achieved by (1) replacing the existing double-bend lattice structure with a five-bend achromat one, (2) lowering the stored beam energy from 8 to 6 GeV, (3) increasing the horizontal damping partition number from 1 to 1.3, and (4) enhancing horizontal radiation damping by installing damping wigglers in long straight sections. The use of short-period in-vacuum undulators allows ultrabrilliant X-rays to be provided while keeping a high-energy spectral range even at the reduced electron-beam energy of 6 GeV. To reduce power consumption, the dedicated, aged injector system has been shut down and the high-performance linear accelerator of SACLA, a compact X-ray free-electron laser (XFEL) facility, is used as the injector of the ring in a time-shared manner. This allows the simultaneous operation of XFEL experiments at SACLA and full/top-up injection of the electron beam into the ring. This paper overviews the concept of the SPring-8-II project, the system design of the light source and the details of the accelerator component design.




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HMRC appoints Modulr as its new CoP supplier

HMRC has appointed




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FilmWeek: ‘F9:The Fast Saga,’ ‘Summer Of Soul,’ ‘Zola’ And More

Sung Kang (L) and Vin Diesel (R) in the film “F9: The Fast Saga"; Credit: Giles Keyte/Universal Pictures

FilmWeek Marquee

Larry Mantle and KPCC film critics Amy Nicholson and Christy Lemire review this weekend’s new movie releases on streaming and on-demand platforms.

This content is from Southern California Public Radio. View the original story at SCPR.org.




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Federal Trade Commission introduces final click-to-cancel rule

The Federal Trade Commission (FTC) has...




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Tintin on acid: Charles Burns ends his dark trilogy with 'Sugar Skull'

Graphic novelist and artist Charles Burns, at the Mohn Broadcast Center, 9/18/2014. He's just completed his trilogy with the new book Sugar Skull.; Credit: John Rabe

Graphic novelist Charles Burns stopped by the Mohn Broadcast Center to talk with Off-Ramp host John Rabe about "Sugar Skull," which completes the trilogy that includes "X'ed Out" and "The Hive."  He's doing a signing tonight (Thurday, Sept. 18) at Skylight Books, 1818 N. Vermont Avenue in Los Feliz.

Why the trilogy? Burns says, "I had finished another book, "Black Hole," which was this very long graphic novel, all in black and white, and I wanted to do something in color, so I conceived a series of books, based on a series of my life, late '70s, the Punk Era. It started that way, and then it turned into something else."

RELATED: Miniaturist Alan Wolfson, or "Honey! I shrunk the strip club!"

The look of Burns' books:

... is drawn from one of his childhood favorites, the Belgian Tintin, who had all sorts of politically incorrect adventures:

"It's called the clear-line school of comics. And it's exactly what it sounds like: very clear lines, but perfectly rendered in color."

If there's more shadow in Burns' books than in Herge's, that's because the lines between good and bad, dark and light, reality and unreality are blurrier in Burns. The trilogy moves back and forth in time and place, including between the normal world and a bizarre world in which a character named Johnny 23 struggles with many of the same issues the protagonist in the real world, Doug, faces... including a pregnant girlfriend.

(From Sugar Skull, by Charles Burns. )

Are they two separate stories or Doug's subconscious world? Burns won't say. "That's for the reader to figure out. I don't really ever clearly explain those things at all, and I like to leave those things open. Interpretation is great, as far as I'm concerned."

Burns turns 59 on Sept. 27. How does he like approaching 60? "As far as the day-to-day landscape, things are more settled in. But as far as my sweltering, swelling, itching brain, that hasn't changed at all unfortunately."




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'Red Band Society' ads pulled from LA buses amid complaints of racism, sexism

"Red Band Society," premieres on Fox September 17th, starring Octavia Spencer, Charlie Rowe and Nolan Sotillo.; Credit: Fox Television Studios

The Los Angeles County Metropolitan Transportation Authority is pulling ads for the Fox television show "Red Band Society" from nearly 200 buses amid complaints they are racist and offensive to women.

The ads show the ensemble cast's members in front of a wall with graffiti describing their characters.

A denigrating word for a woman is used to describe the show's star, Octavia Spencer's character.

The Los Angeles Times reports transit officials began pulling the ads on Wednesday. They had been up for five weeks.

The Red Band Society also shared the ad on its Facebook page in August. 

Facebook: #RedBandSociety ad

But it's since edited it to look like this.

Photo: New ad via Facebook

Protesters who attended Thursday's transit agency board meeting complained the depiction of Spencer's character is racist and offensive to women.

The actress, who plays a nurse in the hospital drama, is black.

She won a supporting actress Oscar for her role in "The Help."




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Facial recognition technique could improve hail forecasts

Full Text:

The same artificial intelligence technique typically used in facial recognition systems could help improve prediction of hailstorms and their severity, according to a new, National Science Foundation-funded study. Instead of zeroing in on the features of an individual face, scientists trained a deep learning model called a convolutional neural network to recognize features of individual storms that affect the formation of hail and how large the hailstones will be, both of which are notoriously difficult to predict. The promising results highlight the importance of taking into account a storm's entire structure, something that's been challenging to do with existing hail-forecasting techniques.

Image credit: Carlye Calvin




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Could graphene-lined clothing prevent mosquito bites?

Full Text:

A new study shows that graphene sheets can block the signals mosquitoes use to identify a blood meal, potentially enabling a new chemical-free approach to mosquito bite prevention. Researchers showed that multilayer graphene can provide a twofold defense against mosquito bites. The ultra-thin yet strong material acts as a barrier that mosquitoes are unable to bite through. At the same time, experiments showed that graphene also blocks chemical signals mosquitoes use to sense that a blood meal is near, blunting their urge to bite in the first place. The findings suggest that clothing with a graphene lining could be an effective mosquito barrier.

Image credit: Hurt Lab/Brown University




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Silver Co. Releases High-Grade Results From Golden Triangle Drilling

Source: Streetwise Reports 11/05/2024

Dolly Varden Silver Corp. (DV:TSX.V; DOLLF:OTCQX) releases new results from its 2024 drilling program at its Kitsault Valley project in British Columbia's Golden Triangle. One analyst says the company is an "attractive target" for large precious metal producers.

Dolly Varden Silver Corp. (DV:TSX.V; DOLLF:OTCQX) released results from five drill holes from its completed 2024 drilling program at its Kitsault Valley project in British Columbia's Golden Triangle.

In total, the program drilled 69 holes for 31,726 meters — 41 holes totaling more than 15,000 meters at the Dolly Varden area and 28 holes totaling more than 16,000 meters at Homestake Ridge.

Highlights of Monday's release include one hole from the Homestake Silver Deposit that found 12.23 grams per tonne gold (g/t Au) and 84 g/t silver (Ag) over 34.93 meters with high-grade breccia veins that included 166 g/t Au and 675 g/t Ag over 0.97 meters.

"The identification of a gold-rich, wide and high-grade area within the Homestake Silver Deposit is highly encouraging," said Chief Executive Officer Shawn Khunkhun. "Our geological team is encouraged by overlapping mineralizing phases of silver and gold-rich veins and breccias; the deposit remains open for expansion."

Technical Analyst Clive Maund, writing on Sunday, called Dolly Varden "one of the best pure silver companies around."

The stock's "breakout at end of last month/early this month was on big volume means it was genuine," Maund wrote.

The stock is at a "classic buy spot, although we should remain aware that it could zigzag a little lower over the short-term, but that said it looks like a strong buy here."

Highlights From Results

Highlights from the Homestake Silver Deposit include:

  • Hole HR24-432: Mineralized envelope including veins: 8.85 g/t Au and 5 g/t Ag over 48.23 meters, including an internal zone of stronger breccia vein intervals grading 29.24 g/t Au and 16 g/t Ag over 13.94 meters, including one breccia vein grading 701 g/t Au and 184 g/t Ag over 0.54 meters.
  • Hole HR24-435: Mineralized envelope including veins: 4.64 g/t Au and 38 g/t Ag over 100.80 meters, including an internal interval of stronger breccia vein mineralization grading 12.23 g/t Au and 84 g/t Ag over 34.93 meters. High-grade breccia veins include 166 g/t Au and 675 g/t Ag over 0.97 meters.
  • Hole HR24-442: Vein breccia zone: 4.58 g/t Au over 9.95 meters, including 14.96 g/t Au over 1.69 meters.

"Results from the five holes in this release suggest that the plunge of mineralization at Homestake Silver has a similar orientation as the Homestake Main Deposit, located 300 meters to the northwest," the company said in a release. "The average grades within these core areas are higher, on a precious metal silver equivalent basis, than the average grade of the silver deposits at the Dolly Varden property further south, due to the increased gold content at the Homestake Ridge Deposits."

Technical Analyst Clive Maund, writing on Sunday, called Dolly Varden "one of the best pure silver companies around."

Drill holes HR24-442 and HR24-445 are step-outs and encountered the mineralized and altered structural corridor of Homestake Silver, the company said. Drill hole HR24-442 intersected a mineralized vein breccia stockwork zone grading 4.58 g/t Au over 9.95 meters, including individual breccias with stronger pyrite mineralization grading 14.96 g/t Au over 1.69 meters.

The Homestake Ridge deposits are interpreted as structurally controlled, multi-phase epithermal vein stockwork and vein breccia system hosted in Jurassic Hazelton volcanic rocks, Dolly Varden noted. Mineralization consists of pyrite plus galena and sphalerite with visible gold in a breccia matrix within a silica breccia vein system.

"The northwest orientation of the main Homestake structural trend appears to have numerous subparallel internal structures that are interpreted to form the controls for higher grade gold and silver shoots within a broader mineralized envelope at the Homestake Silver deposit," the company said. "The main structural corridor dips steeply to the northeast at Homestake Main and rolls to vertical or steeply southwest at Homestake Silver."

Analyst's Response: 'Boom'

Jeff Valks, Senior Analyst for The Gold Advisor newsletter, reacted to the results with the word "BOOM."

"Dolly Varden Silver reports more high-grade drill results from its 2024 exploration program at the Homestake Silver Deposit in British Columbia's Golden Triangle," he wrote on Monday. "Results from five drill holes have confirmed significant gold and silver mineralization in an area targeted within the plunge of a previously undrilled high-grade zone, signaling potential expansion opportunities."

Jeff Valks, Senior Analyst for The Gold Advisor newsletter, reacted to the results with the word "BOOM."

We look forward to the remaining results." Vaks wrote. "In the meantime, the stock is flat as I write but is up over 35% year-to-date. It's not too late to buy, it's down from its recent spike, and as (editor) Jeff (Clark) has said, this is a core holding for the silver bull market. Use a stink bid if you're looking for shares. Both Jeff and I hold long positions."

Analyst Marcus Giannini of Haywood Capital Markets noted in a recent research note that Dolly Varden continues to "push the margins of known high-grade mineralization" at the project.

Gianini gave the stock a Buy rating with a CA$2.40 per share target price. "We continue to view Dolly's high-grade endowment as an increasingly attractive target for larger North American-focused precious metal producers," he noted.

The Catalyst: Analysts Point to Patience

While it has chased the record highs gold has been setting this year, silver recently broke through US$35 per ounce, reflecting a year-to-date gain of about 47%. It has since settled but held to the "crucial US$32.50 level," according to Christopher Lewis of FX Empire on Monday.

"Keep in mind that this is a market that is extraordinarily volatile and, of course, will continue to be noisy over the next couple of days as we get election results in the United States," Lewis wrote. "And of course, we also get the Federal Reserve interest rate decision on Thursday, both of which could cause chaos."

Lewis said he thinks the "least likely path is lower."

"I still favor an upside move, but I recognize that we are definitely in a little bit of a holding pattern," he wrote. "Having said that, if we do see momentum to the upside, then there's really not a whole lot here that could keep this market from trying to challenge the (US$)35 level again, obviously, a large round psychologically significant figure, but we'll just have to wait and see how that plays out."

The most conductive element in nature, silver is used to coat electrical contacts in computers, phones, cars, and appliances. It's also an important element in solar technology.

Mordor Intelligence noted that the white metal is expected to register a compound annual growth rate (CAGR) of more than 5% between 2024 and 2029.

Newsletter editor Brien Lundin encouraged investors not to get discouraged, as any price drop-off is temporary, he said. He expects the silver price to soar when the U.S. Federal Reserve doubles down on its efforts to get interest rates much lower, he wrote on Oct. 23. [OWNERSHIP_CHART-5439]

Based on silver's charts, Ron Struthers of Struthers Resource Stock Report also predicted a major run-up in the silver price.

"Back in April or early May, I highlighted the breakout from a cup and handle formation and [that] that would lead to a major upside move. This is now confirmed," he wrote on Oct. 23.

Ownership and Share Structure

According to the company's latest corporate presentation, 50% of its stock is held by institutional investors, including Fidelity Management & Research Company LLC, Sprott Asset Management LP, U.S. Global Investors Inc., and Delbrook.

About 41% is with strategic investors, including 17% with Fury Gold Mines, 14% with Hecla, and Eric Sprott owns 10% himself.

The rest, 9%, is with retail and high-net-worth investors.

The company has 301.16 million outstanding shares. Its market cap is CA$380.72 million, and its 52-week trading range is CA$0.62–1.46 per share.

Sign up for our FREE newsletter at: www.streetwisereports.com/get-news

Important Disclosures:

  1. Dolly Varden Silver Corp. is a billboard sponsor of Streetwise Reports and pays SWR a monthly sponsorship fee between US$4,000 and US$5,000.
  2. As of the date of this article, officers and/or employees of Streetwise Reports LLC (including members of their household) own securities of Dolly Varden Silver Corp.
  3. Steve Sobek wrote this article for Streetwise Reports LLC and provides services to Streetwise Reports as an employee.
  4. This article does not constitute investment advice and is not a solicitation for any investment. Streetwise Reports does not render general or specific investment advice and the information on Streetwise Reports should not be considered a recommendation to buy or sell any security. Each reader is encouraged to consult with his or her personal financial adviser and perform their own comprehensive investment research. By opening this page, each reader accepts and agrees to Streetwise Reports' terms of use and full legal disclaimer. Streetwise Reports does not endorse or recommend the business, products, services or securities of any company.

For additional disclosures, please click here.

( Companies Mentioned: DV:TSX.V; DOLLF:OTCQX, )




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Gold Co. Announces Resource Expansion Results in Historic Mining District

Source: Streetwise Reports 11/07/2024

Dakota Gold Corp. (DC:NYSE American) announces results from 17 holes in its bid to expand the maiden resource at its Richmond Hill Gold Project in the historic Homestake District of South Dakota. One analyst believes the results support expansion for future resource estimates.

Dakota Gold Corp. (DC:NYSE American) announced drill results from the first 17 holes of its ongoing infill drilling program to expand the maiden resource at its Richmond Hill Gold Project in the historic Homestake District of South Dakota.

An updated S-K 1300 resource estimate is planned for Q1 2025 and a S-K 1300 Initial Assessment with cashflow analysis is planned for Q2 2025, the company said in a release. The expanded resource is expected to include an additional 88 new drill holes totaling 17,000 meters.

"The highlight of this morning's release was (hole) RH24C-099, which was drilled in the Twin Tunnels Zone and returned 1.15 g/t Au (grams per tonne gold) over 51.7 meters from 132.9 meters," wrote Canaccord Genuity Capital Markets Analyst Peter Bell in an updated research note on Monday. "The results this morning were consistent with the current resource at Richmond Hill, with many cases reporting higher-than-average grades."

Bell said the firm was encouraged by the results, "which we believe provide support for expansion in future resource estimates. With infill and step out drilling at Richmond Hill being just one of three ongoing drill programs currently underway at Dakota, underscoring the company's emphasis on exploration and expansion."

Drilling Is 'Adding Ounces'

The maiden S-K 1300 resource, announced in April, outlined an Indicated Resource of 51.83 million tonnes (Mt) at 0.80 g/t Au for 1.33 million ounces (Moz) and Inferred Resource of 58.06 Mt at 0.61 g/t Au for 1.13 Moz., the company said.

The initial infill drill results release released Monday encountered further gold mineralization from the central portion of the Richmond Hill resource area consistent with results reported in the maiden resource, Dakota said. The drilling was conducted in areas where the original resource block model contained gaps to support the company's belief that the initial resource could be significantly expanded with additional infill drilling.

Highlights of the results include:

  • Hole RH24C-077: 0.76 g/t Au over 24.4 meters
  • Hole RH24C-083: 0.70 g/t Au over 13.8 meters
  • Hole RH24C-085: 1.10 g/t Au over 17.9 meters
  • Hole RH24C-088A: 0.96 g/t Au over 41.5 meters
  • Hole RH24C-099: 1.15 g/t Au over 51.7 meters

Dakota said the resource remained open in all directions and could be improved with more drilling, metallurgical work, and incorporation of silver into the resource.

"We are very pleased to see that initial results from our infill drill program are adding ounces to our current S-K 1300 resource," said Dakota Vice President of Exploration James Berry. "The results to date show grades and widths consistent with drill holes in the original block model and support an expansion of gold mineralization, including shallow oxide mineralization. We look forward to continuing our infill program on the other zones identified in our Initial assessment for follow-up drilling."

'Vastly Unexplored' District

The historic Homestake Mine produced 41 Moz Au and 9 Moz silver (Ag) over 126 years. The company has 48,000 acres of holdings surrounding the original mine, which was first discovered in 1876 and consolidated by George Hearst.

Areas surrounding "super-giant deposits" like Homestake are believed to contain significant additional gold resources, wrote John Newell wrote.

Areas surrounding "super-giant deposits" like Homestake are believed to contain significant additional gold resources, wrote John Newell of John Newell & Associates this week for a Streetwise Reports piece on the legacy of the famous mine.

"Super-giant deposits are characterized by clusters of geologically similar deposits within several hundred square kilometers, defining profoundly mineralized regions," Newell wrote. "It is believed that at least twice that amount of gold exists in the neighborhood of these super giants. If that is true, then there are at least 100 Moz of gold left to be found in this vastly underexplored precious metal district of South Dakota."

This proximity to a super-giant "suggests a high potential for similar deposits," Newell wrote. "Being in the shadow of many old mines increases the probability of finding significant mineral resources."

The Catalyst: Gold Continues Bull Market

After hitting a record high of US$2,790.15 per ounce on Thursday, spot gold was up 0.1% to US$2,737.35 on Monday afternoon, according to Reuters.

Investors were keeping a close on Tuesday's presidential election in the U.S. and the Federal Reserve's meeting later this week, Anjana Anil reported.

"A Reuters/Ipsos poll conducted last month found worries that the U.S. could see a repeat of the unrest that followed Trump's 2020 election defeat, when his false claim that his loss was the result of fraud prompted hundreds to storm the U.S. Capitol," Anil wrote.

Gold's rise has "resulted in big returns for the investors who bought in earlier this year," Angelica Leicht reported for CBS News last month. "For example, the investors who purchased gold in March when it hit US$2,160 per ounce have seen their gold values increase by nearly 27% in the time since. That's a huge uptick in value in a matter of months, especially on an asset that's known more for long-term growth."

Recently polled London Bullion Market Association members indicated they believe the gold price could reach US$2,940/oz during 2025, reported Stockhead on Oct. 28.

"Combined with expectations of lower global interest rates, this further enhances gold's attractiveness as an investment," the article noted.[OWNERSHIP_CHART-7442]

As for gold equities, the S&P/TSX Venture Composite Index (SPCDNX) confirmed a multidecade bull run for junior, intermediate, and senior mining stocks when it closed above 1,000 recently, Stewart Thomson with 321Gold wrote. The index is a key indicator of the health of the general gold, silver, and mining stocks market.

Ownership and Share Structure

According to the company, approximately 25% of its shares are with management and insiders.

Out of management, Co-chairman, Director, President and Chief Executive Officer Robert Quartermain holds the most shares at 8.4%, while COO Jerry Aberle holds 4.8%, the company said.

About 26% of the shares are with institutional investors, according to Yahoo Finance and Edgar filings. Top institutional holders include Fourth Sail Capital with 5.3%, Van Eck Associates with 4.1%, Blackrock Institutional Trust Co. with 3.7%, The Vanguard Group Inc. with about 3.2%, Fidelity Management and Research Co. LLC with 2.7%, and CI Global Asset Management with 2.6%.

About 16.5% is with strategic investors, including Orion Mine Finance, which owns about 9.9%, and Barrick Gold Corp., which owns about 2.5%. The rest is retail.

Dakota Gold has a market cap of US$212.61 million, with 93.66 million shares outstanding. It trades in a 52-week range of US$3.25 and US$1.84.

Sign up for our FREE newsletter at: www.streetwisereports.com/get-news

Important Disclosures:

  1. Dakota Gold Corp. is a billboard sponsor of Streetwise Reports and pays SWR a monthly sponsorship fee between US$4,000 and US$5,000.
  2. As of the date of this article, officers and/or employees of Streetwise Reports LLC (including members of their household) own securities of Dakota Gold Corp.
  3. Steve Sobek wrote this article for Streetwise Reports LLC and provides services to Streetwise Reports as an employee.
  4. This article does not constitute investment advice and is not a solicitation for any investment. Streetwise Reports does not render general or specific investment advice and the information on Streetwise Reports should not be considered a recommendation to buy or sell any security. Each reader is encouraged to consult with his or her personal financial adviser and perform their own comprehensive investment research. By opening this page, each reader accepts and agrees to Streetwise Reports' terms of use and full legal disclaimer. Streetwise Reports does not endorse or recommend the business, products, services or securities of any company.

For additional disclosures, please click here.

( Companies Mentioned: DC:NYSE American, )




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Gold Exploration Yields Promising Results, Extending Mineralization Over a Kilometer

Source: Streetwise Reports 11/06/2024

Golden Cariboo Resources Ltd. (GCC:CSE; GCCFF:OTC; A0RLEP:WKN; 3TZ:FSE) has reported encouraging results from its 2024 field campaign. Read more about the significant gold mineralization uncovered and the extension of known deposits by one kilometer.

Golden Cariboo Resources Ltd. (GCC:CSE; GCCFF:OTC; A0RLEP:WKN; 3TZ:FSE) has reported encouraging results from its 2024 field campaign. During the exploration, the company collected 16 rock samples from the Halo zone, North Hixon zone, and Pioneer area. These samples revealed promising gold mineralization in the region. Notable highlights from the Halo zone include grab samples from newly exposed outcrops, with assays reaching 8.47 g/t Au (grams per tonne, gold), 6.59 g/t Au, and 2.39 g/t Au. These samples were taken from altered andesite tuff with quartz-carbonate veins located approximately 101 meters northeast of the nearest drill collar.

Sampling near the Pioneer showing, situated one-kilometer north-northwest of the Halo zone, also returned assays of 1.13 g/t Au and 0.40 g/t Au. The fieldwork's findings have significantly extended the strike length of known gold mineralization by one kilometer and expanded the surface footprint of mineralization to the northeast. Despite challenging glacial cover, Golden Cariboo's team continues to uncover significant gold-bearing outcrops.

The report also underscored the strategic advantages of the property's location, infrastructure, and proximity to Highway 97, which reduces exploration and operational costs. Wortel detailed Golden Cariboo's drilling campaign, which includes results such as Hole QGQ24-013, which intersected 136.51 meters at 1.77 g/t gold, including a higher-grade interval of 23.89 meters at 3.32 g/t gold.

Valuation metrics from the report included a projected fair value of CA$0.40 per share, representing a 74% potential upside from the current trading price of CA$0.23, and doesn't include the added value from recent, significant exploration success. Despite acknowledging the high risks associated with early-stage exploration projects, Couloir Capital emphasized the long-term value potential in a Tier 1 mining jurisdiction, reinforced by the company's experienced management team and promising geological trends.

Frank Callaghan, President and CEO of Golden Cariboo, stated in the news release, "Although there is a lot of glacial cover on this project, our geologists still managed to find new gold-bearing outcrops in areas of great significance. We have now expanded the surface footprint of gold mineralization at the Halo zone to the northeast and increased the strike length of our gold trend. We're in a very large gold system that is being demonstrated by multiple, varied work programs."

Mining and Metals Market

On October 29, Kitco reported that gold prices had reached nearly US$2,800. This price represents a 35% increase for the year. The rise was attributed to multiple factors, including "geopolitical conflicts, Federal Reserve interest rate normalization, continued strong demand from global central banks, and uncertainties about the upcoming presidential election and potential fiscal stimulus." Analysts at Kitco described this combination of elements as a "perfect storm." They noted it had driven investor sentiment and reinforced gold's value as a hedge against economic turmoil.

LiveMint, on October 30, highlighted the substantial returns seen in gold over the past year. Despite this impressive performance, some analysts expressed caution regarding gold's future trajectory. Ajay Kedia, Director of Kedia Advisory, suggested that while gold prices may see a short-term rally, "investors may have to remain cautious on the yellow metal in the second half of 2025." Kedia noted that gold prices could experience profit-taking and a slowdown if interest rate cuts by the Federal Reserve do not materialize as quickly as expected. Nonetheless, gold has continued to serve as a preferred asset for those seeking stability, especially in times of economic and political uncertainty.

In a November 4 report, Egon von Greyerz, Founder and Chairman of Matterhorn Asset Management, provided a historical perspective on gold's role in preserving wealth. Von Greyerz discussed how gold had consistently retained value, even as fiat currencies depreciated over time. He emphasized, "Gold held in the investor's name in safe vaults and jurisdictions outside the financial system is the ultimate form of wealth preservation." Von Greyerz also pointed to gold's outperformance since the 1970s, stating that gold had increased 78 times since President Nixon ended the gold standard in 1971. He argued that gold's journey was "only starting now," citing the ongoing destruction of fiat money value through global debt expansion and monetary policies.

Cariboo Catalysts

According to Golden Cariboo Resources' Q1 2024 investor presentation, the company is advancing exploration on its 3,814-hectare Quesnelle Gold Quartz Mine property, located in British Columbia's historic Cariboo Mining District. The asset benefits from 160 years of mining history and is road-accessible, facilitating year-round exploration. The 2024 exploration program, including trenching and a proposed 2,500-5,000m Phase 2 drilling campaign, aims to delineate the gold system further and complete a National Instrument 43-101 compliant resource estimate.

The property, encircled by Osisko Development Corp. on three sides, holds the potential for high-grade, multi-ounce gold targets. Management is focusing on a multi-phase exploration strategy. This includes trenching to assess shallow overburden and mapping and sampling to refine drill targets. The team's experience and the property's historical and geological significance position Golden Cariboo as a promising exploration venture.

The proposed drilling and development efforts reflect a systematic approach to unlocking value in this underexplored yet historically significant gold camp as the company progresses toward realizing a resource estimate.

Expert Analysis

Golden Cariboo Resources Inc. received favorable coverage from Couloir Capital in a report released on September 3, 2024. Senior Mining Analyst Ron Wortel issued a Buy recommendation for the company, noting the significant potential for discovering a large gold resource at the Quesnelle Gold Quartz property. Wortel highlighted that the property, located in British Columbia's historic Cariboo Mining District, lies along the same geological trend as Osisko Development's projects, suggesting the possibility of tapping into similar high-grade mineralization systems.

The report also underscored the strategic advantages of the property's location, infrastructure, and proximity to Highway 97, which reduces exploration and operational costs. Wortel detailed Golden Cariboo's drilling campaign, pointing out positive early results, such as Hole QGQ24-08, which intersected 263 meters at 0.29 g/t gold, including a higher-grade interval of 200 meters at 0.58 g/t gold. The analyst described these findings as indicative of "bulk-tonnage targets," with visible gold observed in several drill cores, bolstering the outlook for continued exploration success. [OWNERSHIP_CHART-11131]

Valuation metrics from the report included a projected fair value of CA$0.40 per share, representing a 286% potential upside from the current trading price of CA$0.14. Despite acknowledging the high risks associated with early-stage exploration projects, Couloir Capital emphasized the long-term value potential in a Tier 1 mining jurisdiction, reinforced by the company's experienced management team and promising geological trends.

Ownership and Share Structure

According to Golden Cariboo, management and insiders own 30% of Golden Cariboo Resources. President and CEO Frank Callaghan owns 16.45% or 6.93 million shares; Elaine Callaghan has 0.97% or 0.41 million shares; Director Andrew Rees has 0.79% or 0.33 million shares; and Director Laurence Smoliak has 0.3% or 0.13 million shares.

Retail investors hold the remaining. There are no institutional investors.

The company said it has 50.3 million shares outstanding, 24.83 million warrants, and 3.8 million options.

Its market cap is CA$9.7 million. Over the past 52 weeks, Golden Cariboo has traded between CA$0.08 and CA$0.36 per share.

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Important Disclosures:

  1. Golden Cariboo Resources Ltd. has a consulting relationship with Street Smart an affiliate of Streetwise Reports. Street Smart Clients pay a monthly consulting fee between US$8,000 and US$20,000.
  2. As of the date of this article, officers and/or employees of Streetwise Reports LLC (including members of their household) own securities of Golden Cariboo Resources Ltd.
  3. James Guttman wrote this article for Streetwise Reports LLC and provides services to Streetwise Reports as an independent contractor.
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( Companies Mentioned: GCC:CSE; GCCFF:OTC; A0RLEP:WKN;3TZ:FSE, )