osi The incommensurate composite YxOs4B4 (x = 1.161) By journals.iucr.org Published On :: Tetragonal YxOs4B4 (x = 1.161) is an incommensurate composite of columns of Y atoms in a three-dimensional Os4B4 framework. The structure was refined using the superspace approach. Full Article text
osi Variable stoichiometry and salt-cocrystal intermediate in the multicomponents of flucytosine: structural elucidation and its impact on stability By journals.iucr.org Published On :: Five multicomponent solid forms of an antifungal drug flucytosine are reported with a hygroscopic stability study. A detailed CSD search on the cocrystal/salts of flucytosine is evaluated and correlated the structures based on bond angles and bond distances. Full Article text
osi Seed layer formation by deposition of micro-crystallites on a revolving substrate: modeling of the effective linear elastic, piezoelectric, and dielectric coefficients By journals.iucr.org Published On :: The rotating substrate method of crystallite deposition is modeled, allowing computation of effective material coefficients of the layers resulting from the averaging. A worked numerical example particularized to 6mm ZnO is provided. Full Article text
osi The incommensurate composite YxOs4B4 (x = 1.161) By journals.iucr.org Published On :: 2024-10-31 YxOs4B4 (x = 1.161) crystallizes as a tetragonal incommensurate composite of columns of Y atoms extending along [001] in an Os4B4 framework. The structure was refined using the superspace approach. The basic structure of the Y subsystem can be idealized as having I4/mmm symmetry, with a crystallographically unique Y atom located on the 4/mmm position. The actual superspace symmetry is P42/nmc(00σ3)s0s0. The Y atoms feature only subtle positional modulation in the [001] direction. The Os4B4 subsystem [P42/ncm(00σ3)00ss superspace symmetry] is built of columns of edge-sharing Os4 tetrahedra extending along [001] and B2 dumbbells. The Os4 tetrahedra feature pronounced positional modulation with a distinct variation of the Os—Os bond lengths. Modulation of the B2 dumbbells is best described as a rotation about the [001] axis. Full Article text
osi Preliminary X-ray diffraction and ligand-binding analyses of the N-terminal domain of hypothetical protein Rv1421 from Mycobacterium tuberculosis H37Rv By journals.iucr.org Published On :: 2024-06-27 Mycobacterium tuberculosis can reside and persist in deep tissues; latent tuberculosis can evade immune detection and has a unique mechanism to convert it into active disease through reactivation. M. tuberculosis Rv1421 (MtRv1421) is a hypothetical protein that has been proposed to be involved in nucleotide binding-related metabolism in cell-growth and cell-division processes. However, due to a lack of structural information, the detailed function of MtRv1421 remains unclear. In this study, a truncated N-terminal domain (NTD) of MtRv1421, which contains a Walker A/B-like motif, was purified and crystallized using PEG 400 as a precipitant. The crystal of MtRv1421-NTD diffracted to a resolution of 1.7 Å and was considered to belong to either the C-centered monoclinic space group C2 or the I-centered orthorhombic space group I222, with unit-cell parameters a = 124.01, b = 58.55, c = 84.87 Å, β = 133.12° or a = 58.53, b = 84.86, c = 90.52 Å, respectively. The asymmetric units of the C2 or I222 crystals contained two or one monomers, respectively. In terms of the binding ability of MtRv1421-NTD to various ligands, uridine diphosphate (UDP) and UDP-N-acetylglucosamine significantly increased the melting temperature of MtRv1421-NTD, which indicates structural stabilization through the binding of these ligands. Altogether, the results reveal that a UDP moiety may be required for the interaction of MtRv1421-NTD as a nucleotide-binding protein with its ligand. Full Article text
osi Crystal structure of guanosine 5'-monophosphate synthetase from the thermophilic bacterium Thermus thermophilus HB8 By journals.iucr.org Published On :: 2024-09-18 Guanosine 5'-monophosphate (GMP) synthetase (GuaA) catalyzes the last step of GMP synthesis in the purine nucleotide biosynthetic pathway. This enzyme catalyzes a reaction in which xanthine 5'-monophosphate (XMP) is converted to GMP in the presence of Gln and ATP through an adenyl-XMP intermediate. A structure of an XMP-bound form of GuaA from the domain Bacteria has not yet been determined. In this study, the crystal structure of an XMP-bound form of GuaA from the thermophilic bacterium Thermus thermophilus HB8 (TtGuaA) was determined at a resolution of 2.20 Å and that of an apo form of TtGuaA was determined at 2.10 Å resolution. TtGuaA forms a homodimer, and the monomer is composed of three domains, which is a typical structure for GuaA. Disordered regions in the crystal structure were obtained from the AlphaFold2-predicted model structure, and a model with substrates (Gln, XMP and ATP) was constructed for molecular-dynamics (MD) simulations. The structural fluctuations of the TtGuaA dimer as well as the interactions between the active-site residues were analyzed by MD simulations. Full Article text
osi Position-independent product increase rate in a shaker mill revealed by position-resolved in situ synchrotron powder X-ray diffraction By journals.iucr.org Published On :: The position- and time-resolved monitoring of a mechanochemical reaction using synchrotron powder X-ray diffraction revealed a position-independent increase rate of product in the jar of a shaker mill. Full Article text
osi Position-independent product increase rate in a shaker mill revealed by position-resolved in situ synchrotron powder X-ray diffraction By journals.iucr.org Published On :: 2024-11-08 We investigated the position and time dependence of a mechanochemical reaction induced by ball milling using in situ synchrotron powder X-ray diffraction with changing X-ray irradiation position. The mechanochemical reduction of AgCl with Cu was monitored in situ with the X-rays incident at two different vertical positions on the jar. Our previously developed multi-distance Rietveld method was applied to analyze the in situ diffraction data with a 1 min resolution. Both the vertical and the horizontal sample positions were determined using the sample-to-detector distances from the in situ data. Position dependence was found in the powder spreading and induction time. We reveal that the increase rate of the product is independent of the sample position when measured with a 1 min time resolution, confirming the validity of in situ monitoring of part of the space in a milling jar for a gradual mechanochemical reaction. Full Article text
osi Deep learning to overcome Zernike phase-contrast nanoCT artifacts for automated micro-nano porosity segmentation in bone By journals.iucr.org Published On :: 2024-01-01 Bone material contains a hierarchical network of micro- and nano-cavities and channels, known as the lacuna-canalicular network (LCN), that is thought to play an important role in mechanobiology and turnover. The LCN comprises micrometer-sized lacunae, voids that house osteocytes, and submicrometer-sized canaliculi that connect bone cells. Characterization of this network in three dimensions is crucial for many bone studies. To quantify X-ray Zernike phase-contrast nanotomography data, deep learning is used to isolate and assess porosity in artifact-laden tomographies of zebrafish bones. A technical solution is proposed to overcome the halo and shade-off domains in order to reliably obtain the distribution and morphology of the LCN in the tomographic data. Convolutional neural network (CNN) models are utilized with increasing numbers of images, repeatedly validated by `error loss' and `accuracy' metrics. U-Net and Sensor3D CNN models were trained on data obtained from two different synchrotron Zernike phase-contrast transmission X-ray microscopes, the ANATOMIX beamline at SOLEIL (Paris, France) and the P05 beamline at PETRA III (Hamburg, Germany). The Sensor3D CNN model with a smaller batch size of 32 and a training data size of 70 images showed the best performance (accuracy 0.983 and error loss 0.032). The analysis procedures, validated by comparison with human-identified ground-truth images, correctly identified the voids within the bone matrix. This proposed approach may have further application to classify structures in volumetric images that contain non-linear artifacts that degrade image quality and hinder feature identification. Full Article text
osi Image registration for in situ X-ray nano-imaging of a composite battery cathode with deformation By journals.iucr.org Published On :: 2024-02-01 The structural and chemical evolution of battery electrodes at the nanoscale plays an important role in affecting the cell performance. Nano-resolution X-ray microscopy has been demonstrated as a powerful technique for characterizing the evolution of battery electrodes under operating conditions with sensitivity to their morphology, compositional distribution and redox heterogeneity. In real-world batteries, the electrode could deform upon battery operation, causing challenges for the image registration which is necessary for several experimental modalities, e.g. XANES imaging. To address this challenge, this work develops a deep-learning-based method for automatic particle identification and tracking. This approach was not only able to facilitate image registration with good robustness but also allowed quantification of the degree of sample deformation. The effectiveness of the method was first demonstrated using synthetic datasets with known ground truth. The method was then applied to an experimental dataset collected on an operating lithium battery cell, revealing a high degree of intra- and interparticle chemical complexity in operating batteries. Full Article text
osi In situ photodeposition of ultra-small palladium particles on TiO2 By journals.iucr.org Published On :: 2024-07-15 In situ and operando investigation of photocatalysts plays a fundamental role in understanding the processes of active phase formation and the mechanisms of catalytic reactions, which is crucial for the rational design of more efficient materials. Using a custom-made operando photocatalytic cell, an in situ procedure to follow the formation steps of Pd/TiO2 photocatalyst by synchrotron-based X-ray absorption spectroscopy (XAS) is proposed. The procedure resulted in the formation of ∼1 nm Pd particles with a much narrower size distribution and homogeneous spreading over TiO2 support compared with the samples generated in a conventional batch reactor. The combination of in situ XAS spectroscopy with high-angle annular dark-field scanning transmission electron microscopy demonstrated the formation of single-atom Pd(0) sites on TiO2 as the initial step of the photodeposition process. Palladium hydride particles were observed for all investigated samples upon exposure to formic acid solutions. Full Article text
osi Development of an X-ray ionization beam position monitor for PAL-XFEL soft X-rays By journals.iucr.org Published On :: 2024-07-29 The Pohang Accelerator Laboratory X-ray Free-Electron Laser (PAL-XFEL) operates hard X-ray and soft X-ray beamlines for conducting scientific experiments providing intense ultrashort X-ray pulses based on the self-amplified spontaneous emission (SASE) process. The X-ray free-electron laser is characterized by strong pulse-to-pulse fluctuations resulting from the SASE process. Therefore, online photon diagnostics are very important for rigorous measurements. The concept of photo-absorption and emission using solid materials is seldom considered in soft X-ray beamline diagnostics. Instead, gas monitoring detectors, which utilize the photo-ionization of noble gas, are employed for monitoring the beam intensity. To track the beam position at the soft X-ray beamline in addition to those intensity monitors, an X-ray ionization beam position monitor (XIBPM) has been developed and characterized at the soft X-ray beamline of PAL-XFEL. The XIBPM utilizes ionization of either the residual gas in an ultra-high-vacuum environment or injected krypton gas, along with a microchannel plate with phosphor. The XIBPM was tested separately for monitoring horizontal and vertical beam positions, confirming the feasibility of tracking relative changes in beam position both on average and down to single-shot measurements. This paper presents the basic structure and test results of the newly developed non-invasive XIBPM. Full Article text
osi Diamond sensors for hard X-ray energy and position resolving measurements at the European XFEL By journals.iucr.org Published On :: 2024-07-30 The diagnostics of X-ray beam properties has a critical importance at the European X-ray Free-Electron Laser facility. Besides existing diagnostic components, utilization of a diamond sensor was proposed to achieve radiation-hard, non-invasive beam position and pulse energy measurements for hard X-rays. In particular, with very hard X-rays, diamond-based sensors become a useful complement to gas-based devices which lose sensitivity due to significantly reduced gas cross-sections. The measurements presented in this work were performed with diamond sensors consisting of an electronic-grade single-crystal chemical-vapor-deposition diamond with position-sensitive resistive electrodes in a duo-lateral configuration. The results show that the diamond sensor delivers pulse-resolved X-ray beam position data at 2.25 MHz with an uncertainty of less than 1% of the beam size. To our knowledge this is the first demonstration of pulse-resolved position measurements at the MHz rate using a transmissive diamond sensor at a free-electron laser facility. It can therefore be a valuable tool for X-ray free-electron lasers, especially for high-repetition-rate machines, enabling applications such as beam-based alignment and intra-pulse-train position feedback. Full Article text
osi The diamond–silicon carbide composite Skeleton® as a promising material for substrates of intense X-ray beam optics By journals.iucr.org Published On :: 2024-08-06 The paper considers the possibility of using the diamond-silicon carbide composite Skeleton® with a technological coating of polycrystalline silicon as a substrate for X-ray mirrors used with powerful synchrotron radiation sources (third+ and fourth generation). Samples were studied after polishing to provide the following surface parameters: root-mean-square flatness ≃ 50 nm, micro-roughness on the frame 2 µm × 2 µm σ ≃ 0.15 nm. The heat capacity, thermal conductivity and coefficient of linear thermal expansion were investigated. For comparison, a monocrystalline silicon sample was studied under the same conditions using the same methods. The value of the coefficient of linear thermal expansion turned out to be higher than that of monocrystalline silicon and amounted to 4.3 × 10−6 K−1, and the values of thermal conductivity (5.0 W cm−1 K−1) and heat capacity (1.2 J K−1 g−1) also exceeded the values for Si. Thermally induced deformations of both Skeleton® and monocrystalline silicon samples under irradiation with a CO2 laser beam have also been experimentally studied. Taking into account the obtained thermophysical constants, the calculation of thermally induced deformation under irradiation with hard (20 keV) X-rays showed almost three times less deformation of the Skeleton® sample than of the monocrystalline silicon sample. Full Article text
osi Development of an advanced in-line multilayer deposition system at Diamond Light Source By journals.iucr.org Published On :: 2024-08-09 A state-of-the-art multilayer deposition system with a 4200 mm-long linear substrate translator housed within an ultra-high vacuum chamber has been developed. This instrument is engineered to produce single and multilayer coatings, accommodating mirrors up to 2000 mm in length through the utilization of eight rectangular cathodes. To ensure the quality and reliability of the coatings, the system incorporates various diagnostic tools for in situ thickness uniformity and stress measurement. Furthermore, the system features an annealing process capable of heating up to 700°C within the load-lock chamber. The entire operation, including pump down, deposition and venting processes, is automated through user-friendly software. In addition, all essential log data, power of sputtering source, working pressure and motion positions are automatically stored for comprehensive data analysis. Preliminary commissioning results demonstrate excellent lateral film thickness uniformity, achieving 0.26% along the translation direction over 1500 mm in dynamic mode. The multilayer deposition system is poised for use in fabricating periodic, lateral-graded and depth-graded multilayers, specifically catering to the beamlines for diverse scientific applications at Diamond Light Source. Full Article text
osi Prediction of the treatment effect of FLASH radiotherapy with synchrotron radiation from the Circular Electron–Positron Collider (CEPC) By journals.iucr.org Published On :: 2024-08-22 The Circular Electron–Positron Collider (CEPC) in China can also work as an excellent powerful synchrotron light source, which can generate high-quality synchrotron radiation. This synchrotron radiation has potential advantages in the medical field as it has a broad spectrum, with energies ranging from visible light to X-rays used in conventional radiotherapy, up to several megaelectronvolts. FLASH radiotherapy is one of the most advanced radiotherapy modalities. It is a radiotherapy method that uses ultra-high dose rate irradiation to achieve the treatment dose in an instant; the ultra-high dose rate used is generally greater than 40 Gy s−1, and this type of radiotherapy can protect normal tissues well. In this paper, the treatment effect of CEPC synchrotron radiation for FLASH radiotherapy was evaluated by simulation. First, a Geant4 simulation was used to build a synchrotron radiation radiotherapy beamline station, and then the dose rate that the CEPC can produce was calculated. A physicochemical model of radiotherapy response kinetics was then established, and a large number of radiotherapy experimental data were comprehensively used to fit and determine the functional relationship between the treatment effect, dose rate and dose. Finally, the macroscopic treatment effect of FLASH radiotherapy was predicted using CEPC synchrotron radiation through the dose rate and the above-mentioned functional relationship. The results show that the synchrotron radiation beam from the CEPC is one of the best beams for FLASH radiotherapy. Full Article text
osi α-d-2'-Deoxyadenosine, an irradiation product of canonical DNA and a component of anomeric nucleic acids: crystal structure, packing and Hirshfeld surface analysis By journals.iucr.org Published On :: 2024-01-22 α-d-2'-Deoxyribonucleosides are products of the γ-irradiation of DNA under oxygen-free conditions and are constituents of anomeric DNA. They are not found as natural building blocks of canonical DNA. Reports on their conformational properties are limited. Herein, the single-crystal X-ray structure of α-d-2'-deoxyadenosine (α-dA), C10H13N5O3, and its conformational parameters were determined. In the crystalline state, α-dA forms two conformers in the asymmetric unit which are connected by hydrogen bonds. The sugar moiety of each conformer is arranged in a `clamp'-like fashion with respect to the other conformer, forming hydrogen bonds to its nucleobase and sugar residue. For both conformers, a syn conformation of the nucleobase with respect to the sugar moiety was found. This is contrary to the anti conformation usually preferred by α-nucleosides. The sugar conformation of both conformers is C2'-endo, and the 5'-hydroxyl groups are in a +sc orientation, probably due to the hydrogen bonds formed by the conformers. The formation of the supramolecular assembly of α-dA is controlled by hydrogen bonding and stacking interactions, which was verified by a Hirshfeld and curvedness surface analysis. Chains of hydrogen-bonded nucleobases extend parallel to the b direction and are linked to equivalent chains by hydrogen bonds involving the sugar moieties to form a sheet. A comparison of the solid-state structures of the anomeric 2'-deoxyadenosines revealed significant differences of their conformational parameters. Full Article text
osi Crystal structure and analytical profile of 1,2-diphenyl-2-pyrrolidin-1-ylethanone hydrochloride or `α-D2PV': a synthetic cathinone seized by law enforcement, along with its diluent sugar, myo-inositol By journals.iucr.org Published On :: 2024-01-22 A confiscated package of street drugs was characterized by the usual mass spectral (MS) and FT–IR analyses. The confiscated powder material was highly crystalline and was found to consist of two very different species, accidentally of sizes convenient for X-ray diffraction. Thus, one each was selected and redundant complete sets of data were collected at 100 K using Cu Kα radiation. The selected crystals contained: (a) 1,2-diphenyl-2-(pyrrolidin-1-yl)ethanone hydrochloride hemihydrate or 1-(2-oxo-1,2-diphenylethyl)pyrrolidin-1-ium chloride hemihydrate, C18H20NO+·Cl−·0.5H2O, (I), a synthetic cathinone called `α-D2PV', and (b) the sugar myo-inositol, C6H12O6, (II), probably the only instance in which the drug and its diluent have been fully characterized from a single confiscated sample. Moreover, the structural details of both are rather attractive showing: (i) interesting hydrogen bonding observed in pairwise interactions by the drug molecules, mediated by the chloride counter-anions and the waters of crystallization, and (ii) π–π interactions in the case of the phenyl rings of the drug which are of two different types, namely, π–π stacking and edge-to-π. Finally, the inositol crystallizes with Z' = 2 and the resulting diastereoisomers were examined by overlay techniques. Full Article text
osi EMinsight: a tool to capture cryoEM microscope configuration and experimental outcomes for analysis and deposition By journals.iucr.org Published On :: 2024-03-26 The widespread adoption of cryoEM technologies for structural biology has pushed the discipline to new frontiers. A significant worldwide effort has refined the single-particle analysis (SPA) workflow into a reasonably standardized procedure. Significant investments of development time have been made, particularly in sample preparation, microscope data-collection efficiency, pipeline analyses and data archiving. The widespread adoption of specific commercial microscopes, software for controlling them and best practices developed at facilities worldwide has also begun to establish a degree of standardization to data structures coming from the SPA workflow. There is opportunity to capitalize on this moment in the maturation of the field, to capture metadata from SPA experiments and correlate the metadata with experimental outcomes, which is presented here in a set of programs called EMinsight. This tool aims to prototype the framework and types of analyses that could lead to new insights into optimal microscope configurations as well as to define methods for metadata capture to assist with the archiving of cryoEM SPA data. It is also envisaged that this tool will be useful to microscope operators and facilities looking to rapidly generate reports on SPA data-collection and screening sessions. Full Article text
osi Crystallographic fragment-binding studies of the Mycobacterium tuberculosis trifunctional enzyme suggest binding pockets for the tails of the acyl-CoA substrates at its active sites and a potential substrate-channeling path between them By journals.iucr.org Published On :: 2024-07-16 The Mycobacterium tuberculosis trifunctional enzyme (MtTFE) is an α2β2 tetrameric enzyme in which the α-chain harbors the 2E-enoyl-CoA hydratase (ECH) and 3S-hydroxyacyl-CoA dehydrogenase (HAD) active sites, and the β-chain provides the 3-ketoacyl-CoA thiolase (KAT) active site. Linear, medium-chain and long-chain 2E-enoyl-CoA molecules are the preferred substrates of MtTFE. Previous crystallographic binding and modeling studies identified binding sites for the acyl-CoA substrates at the three active sites, as well as the NAD binding pocket at the HAD active site. These studies also identified three additional CoA binding sites on the surface of MtTFE that are different from the active sites. It has been proposed that one of these additional sites could be of functional relevance for the substrate channeling (by surface crawling) of reaction intermediates between the three active sites. Here, 226 fragments were screened in a crystallographic fragment-binding study of MtTFE crystals, resulting in the structures of 16 MtTFE–fragment complexes. Analysis of the 121 fragment-binding events shows that the ECH active site is the `binding hotspot' for the tested fragments, with 41 binding events. The mode of binding of the fragments bound at the active sites provides additional insight into how the long-chain acyl moiety of the substrates can be accommodated at their proposed binding pockets. In addition, the 20 fragment-binding events between the active sites identify potential transient binding sites of reaction intermediates relevant to the possible channeling of substrates between these active sites. These results provide a basis for further studies to understand the functional relevance of the latter binding sites and to identify substrates for which channeling is crucial. Full Article text
osi Structural studies of β-glucosidase from the thermophilic bacterium Caldicellulosiruptor saccharolyticus By journals.iucr.org Published On :: 2024-10-01 β-Glucosidase from the thermophilic bacterium Caldicellulosiruptor saccharolyticus (Bgl1) has been denoted as having an attractive catalytic profile for various industrial applications. Bgl1 catalyses the final step of in the decomposition of cellulose, an unbranched glucose polymer that has attracted the attention of researchers in recent years as it is the most abundant renewable source of reduced carbon in the biosphere. With the aim of enhancing the thermostability of Bgl1 for a broad spectrum of biotechnological processes, it has been subjected to structural studies. Crystal structures of Bgl1 and its complex with glucose were determined at 1.47 and 1.95 Å resolution, respectively. Bgl1 is a member of glycosyl hydrolase family 1 (GH1 superfamily, EC 3.2.1.21) and the results showed that the 3D structure of Bgl1 follows the overall architecture of the GH1 family, with a classical (β/α)8 TIM-barrel fold. Comparisons of Bgl1 with sequence or structural homologues of β-glucosidase reveal quite similar structures but also unique structural features in Bgl1 with plausible functional roles. Full Article text
osi Comprehensive encoding of conformational and compositional protein structural ensembles through the mmCIF data structure By journals.iucr.org Published On :: 2024-06-25 In the folded state, biomolecules exchange between multiple conformational states crucial for their function. However, most structural models derived from experiments and computational predictions only encode a single state. To represent biomolecules accurately, we must move towards modeling and predicting structural ensembles. Information about structural ensembles exists within experimental data from X-ray crystallography and cryo-electron microscopy. Although new tools are available to detect conformational and compositional heterogeneity within these ensembles, the legacy PDB data structure does not robustly encapsulate this complexity. We propose modifications to the macromolecular crystallographic information file (mmCIF) to improve the representation and interrelation of conformational and compositional heterogeneity. These modifications will enable the capture of macromolecular ensembles in a human and machine-interpretable way, potentially catalyzing breakthroughs for ensemble–function predictions, analogous to the achievements of AlphaFold with single-structure prediction. Full Article text
osi Using deep-learning predictions reveals a large number of register errors in PDB depositions By journals.iucr.org Published On :: 2024-10-10 The accuracy of the information in the Protein Data Bank (PDB) is of great importance for the myriad downstream applications that make use of protein structural information. Despite best efforts, the occasional introduction of errors is inevitable, especially where the experimental data are of limited resolution. A novel protein structure validation approach based on spotting inconsistencies between the residue contacts and distances observed in a structural model and those computationally predicted by methods such as AlphaFold2 has previously been established. It is particularly well suited to the detection of register errors. Importantly, this new approach is orthogonal to traditional methods based on stereochemistry or map–model agreement, and is resolution independent. Here, thousands of likely register errors are identified by scanning 3–5 Å resolution structures in the PDB. Unlike most methods, the application of this approach yields suggested corrections to the register of affected regions, which it is shown, even by limited implementation, lead to improved refinement statistics in the vast majority of cases. A few limitations and confounding factors such as fold-switching proteins are characterized, but this approach is expected to have broad application in spotting potential issues in current accessions and, through its implementation and distribution in CCP4, helping to ensure the accuracy of future depositions. Full Article text
osi Elastic and inelastic strain in submicron-thick ZnO epilayers grown on r-sapphire substrates by metal–organic vapour phase deposition By journals.iucr.org Published On :: 2024-02-13 A significant part of the present and future of optoelectronic devices lies on thin multilayer heterostructures. Their optical properties depend strongly on strain, being essential to the knowledge of the stress level to optimize the growth process. Here the structural and microstructural characteristics of sub-micron a-ZnO epilayers (12 to 770 nm) grown on r-sapphire by metal–organic chemical vapour deposition are studied. Morphological and structural studies have been made using scanning electron microscopy and high-resolution X-ray diffraction. Plastic unit-cell distortion and corresponding strain have been determined as a function of film thickness. A critical thickness has been observed as separating the non-elastic/elastic states with an experimental value of 150–200 nm. This behaviour has been confirmed from ultraviolet photoelectron spectroscopy, X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy measurements. An equation that gives the balance of strains is proposed as an interesting method to experimentally determine this critical thickness. It is concluded that in the thinnest films an elongation of the Zn—O bond takes place and that the plastic strained ZnO films relax through nucleation of misfit dislocations, which is a consequence of three-dimensional surface morphology. Full Article text
osi Crystal structures of two new high-pressure oxynitrides with composition SnGe4N4O4, from single-crystal electron diffraction By journals.iucr.org Published On :: 2024-05-08 SnGe4N4O4 was synthesized at high pressure (16 and 20 GPa) and high temperature (1200 and 1500°C) in a large-volume press. Powder X-ray diffraction experiments using synchrotron radiation indicate that the derived samples are mixtures of known and unknown phases. However, the powder X-ray diffraction patterns are not sufficient for structural characterization. Transmission electron microscopy studies reveal crystals of several hundreds of nanometres in size with different chemical composition. Among them, crystals of a previously unknown phase with stoichiometry SnGe4N4O4 were detected and investigated using automated diffraction tomography (ADT), a three-dimensional electron diffraction method. Via ADT, the crystal structure could be determined from single nanocrystals in space group P63mc, exhibiting a nolanite-type structure. This was confirmed by density functional theory calculations and atomic resolution scanning transmission electron microscopy images. In one of the syntheses runs a rhombohedral 6R polytype of SnGe4N4O4 could be found together with the nolanite-type SnGe4N4O4. The structure of this polymorph was solved as well using ADT. Full Article text
osi K0.72Na1.71Ca5.79Si6O19 – the first oligosilicate based on [Si6O19]-hexamers and its stability compared to cyclosilicates By journals.iucr.org Published On :: 2024-08-30 Synthesis experiments were conducted in the quaternary system K2O–Na2O–CaO–SiO2, resulting in the formation of a previously unknown compound with the composition K0.72Na1.71Ca5.79Si6O19. Single crystals of sufficient size and quality were recovered from a starting mixture with a K2O:Na2O:CaO:SiO2 molar ratio of 1.5:0.5:2:3. The mixture was confined in a closed platinum tube and slowly cooled from 1150°C at a rate of 0.1°C min−1 to 700°C before being finally quenched in air. The structure has tetragonal symmetry and belongs to space group P4122 (No. 91), with a = 7.3659 (2), c = 32.2318 (18) Å, V = 1748.78 (12) Å3, and Z = 4. The silicate anion consists of highly puckered, unbranched six-membered oligomers with the composition [Si6O19] and point group symmetry 2 (C2). Although several thousands of natural and synthetic oxosilicates have been structurally characterized, this compound is the first representative of a catena-hexasilicate anion, to the best of our knowledge. Structural investigations were completed using Raman spectroscopy. The spectroscopic data was interpreted and the bands were assigned to certain vibrational species with the support of density functional theory at the HSEsol level of theory. To determine the stability properties of the novel oligosilicate compared to those of the chemically and structurally similar cyclosilicate combeite, we calculated the electronegativity of the respective structures using the electronegativity equalization method. The results showed that the molecular electronegativity of the cyclosilicate was significantly higher than that of the oligostructure due to the different connectivities of the oxygen atoms within the molecular units. Full Article text
osi Crystal structure of a water oxidation catalyst solvate with composition (NH4)2[FeIV(L-6H)]·3CH3COOH (L = clathrochelate ligand) By journals.iucr.org Published On :: 2024-01-01 The synthetic availability of molecular water oxidation catalysts containing high-valent ions of 3d metals in the active site is a prerequisite to enabling photo- and electrochemical water splitting on a large scale. Herein, the synthesis and crystal structure of diammonium {μ-1,3,4,7,8,10,12,13,16,17,19,22-dodecaazatetracyclo[8.8.4.13,17.18,12]tetracosane-5,6,14,15,20,21-hexaonato}ferrate(IV) acetic acid trisolvate, (NH4)2[FeIV(C12H12N12O6)]·3CH3COOH or (NH4)2[FeIV(L–6H)]·3CH3COOH is reported. The FeIV ion is encapsulated by the macropolycyclic ligand, which can be described as a dodeca-aza-quadricyclic cage with two capping triazacyclohexane fragments making three five- and six six-membered alternating chelate rings with the central FeIV ion. The local coordination environment of FeIV is formed by six deprotonated hydrazide nitrogen atoms, which stabilize the unusual oxidation state. The FeIV ion lies on a twofold rotation axis (multiplicity 4, Wyckoff letter e) of the space group C2/c. Its coordination geometry is intermediate between a trigonal prism (distortion angle φ = 0°) and an antiprism (φ = 60°) with φ = 31.1°. The Fe—N bond lengths lie in the range 1.9376 (13)–1.9617 (13) Å, as expected for tetravalent iron. Structure analysis revealed that three acetic acid molecules additionally co-crystallize per one iron(IV) complex, and one of them is positionally disordered over four positions. In the crystal structure, the ammonium cations, complex dianions and acetic acid molecules are interconnected by an intricate system of hydrogen bonds, mainly via the oxamide oxygen atoms acting as acceptors. Full Article text
osi Crystal structures of four thioglycosides involving carbamimidothioate groups By journals.iucr.org Published On :: 2024-07-09 The compounds 2',3',4',6'-tetra-O-acetyl-β-d-glucopyranosyl N'-cyano-N-phenylcarbamimidothioate (C22H25N3O9S, 5a), 2',3',4',6'-tetra-O-acetyl-β-d-galactopyranosyl N'-cyano-N-phenylcarbamimidothioate, (C22H25N3O9S, 5b), 2',3',4',6'-tetra-O-acetyl-β-d-galactopyranosyl N'-cyano-N-methylcarbamimidothioate (C17H23N3O9S, 5c), and 2',3',4',6'-tetra-O-acetyl-β-d-galactopyranosyl N'-cyano-N-p-tolylcarbamimidothioate (C23H27N3O9S, 5d) all crystallize in P212121 with Z = 4. For all four structures, the configuration across the central (formal) C=N(CN) double bond of the carbamimidothioate group is Z. The torsion angles C5—O1—C1—S (standard sugar numbering) are all close to 180°, confirming the β position of the substituent. Compound 5b involves an intramolecular hydrogen bond N—H⋯O1; in 5c this contact is the weaker branch of a three-centre interaction, whereas in 5a and 5d the H⋯O distances are much longer and do not represent significant interactions. The C—N bond lengths at the central carbon atom of the carbamimidothioate group are almost equal. All C—O—C=O torsion angles of the acetyl groups correspond to a synperiplanar geometry, but otherwise all four molecules display a high degree of conformational flexibility, with many widely differing torsion angles for equivalent groups. In the crystal packing, 5a, 5c and 5d form layer structures involving the classical hydrogen bond N—H⋯Ncyano and a variety of ‘weak’ hydrogen bonds C—H⋯O or C—H⋯S. The packing of 5b is almost featureless and involves a large number of borderline ‘weak’ hydrogen bonds. In an appendix, a potted history of wavelength preferences for structure determination is presented and it is recommended that, even for small organic crystals in non-centrosymmetric space groups, the use of Mo radiation should be considered. Full Article text
osi Three-dimensional alkaline earth metal–organic framework poly[[μ-aqua-aquabis(μ3-carbamoylcyanonitrosomethanido)barium] monohydrate] and its thermal decomposition By journals.iucr.org Published On :: 2024-08-30 In the structure of the title salt, {[Ba(μ3-C3H2N3O2)2(μ-H2O)(H2O)]·H2O}n, the barium ion and all three oxygen atoms of the water molecules reside on a mirror plane. The hydrogen atoms of the bridging water and the solvate water molecules are arranged across a mirror plane whereas all atoms of the monodentate aqua ligand are situated on this mirror plane. The distorted ninefold coordination of the Ba ions is completed with four nitroso-, two carbonyl- and three aqua-O atoms at the distances of 2.763 (3)–2.961 (4) Å and it is best described as tricapped trigonal prism. The three-dimensional framework structure is formed by face-sharing of the trigonal prisms, via μ-nitroso- and μ-aqua-O atoms, and also by the bridging coordination of the anions via carbonyl-O atoms occupying two out of the three cap positions. The solvate water molecules populate the crystal channels and facilitate a set of four directional hydrogen bonds. The principal Ba–carbamoylcyanonitrosomethanido linkage reveals a rare example of the inherently polar binodal six- and three-coordinated bipartite topology (three-letter notation sit). It suggests that small resonance-stabilized cyanonitroso anions can be utilized as bridging ligands for the supramolecular synthesis of MOF solids. Such an outcome may be anticipated for a broader range of hard Lewis acidic alkaline earth metal ions, which perfectly match the coordination preferences of highly nucleophilic nitroso-O atoms. Thermal analysis reveals two-stage dehydration of the title compound (383 and 473 K) followed by decomposition with release of CO2, HCN and H2O at 558 K. Full Article text
osi SEB: a computational tool for symbolic derivation of the small-angle scattering from complex composite structures By journals.iucr.org Published On :: 2024-03-31 Analysis of small-angle scattering (SAS) data requires intensive modeling to infer and characterize the structures present in a sample. This iterative improvement of models is a time-consuming process. Presented here is Scattering Equation Builder (SEB), a C++ library that derives exact analytic expressions for the form factors of complex composite structures. The user writes a small program that specifies how the sub-units should be linked to form a composite structure and calls SEB to obtain an expression for the form factor. SEB supports e.g. Gaussian polymer chains and loops, thin rods and circles, solid spheres, spherical shells and cylinders, and many different options for how these can be linked together. The formalism behind SEB is presented and simple case studies are given, such as block copolymers with different types of linkage, as well as more complex examples, such as a random walk model of 100 linked sub-units, dendrimers, polymers and rods attached to the surfaces of geometric objects, and finally the scattering from a linear chain of five stars, where each star is built up of four diblock copolymers. These examples illustrate how SEB can be used to develop complex models and hence reduce the cost of analyzing SAS data. Full Article text
osi Novel high-efficiency 2D position-sensitive ZnS:Ag/6LiF scintillator detector for neutron diffraction By journals.iucr.org Published On :: 2024-05-10 Scintillator-based ZnS:Ag/6LiF neutron detectors have been under development at ISIS for more than three decades. Continuous research and development aim to improve detector capabilities, achieve better performance and meet the increasingly demanding requirements set by neutron instruments. As part of this program, a high-efficiency 2D position-sensitive scintillator detector with wavelength-shifting fibres has been developed for neutron-diffraction applications. The detector consists of a double scintillator-fibre layer to improve detection efficiency. Each layer is made up of two orthogonal fibre planes placed between two ZnS:Ag/6LiF scintillator screens. Thin reflective foils are attached to the front and back scintillators of each layer to minimize light cross-talk between layers. The detector has an active area of 192 × 192 mm with a square pixel size of 3 × 3 mm. As part of the development process of the double-layer detector, a single-layer detector was built, together with a prototype detector in which the two layers of the detector could be read out separately. Efficiency calculations and measurements of all three detectors are discussed. The novel double-layer detector has been installed and tested on the SXD diffractometer at ISIS. The detector performance is compared with the current scintillator detectors employed on SXD by studying reference crystal samples. More than a factor of 3 improvement in efficiency is achieved with the double-layer wavelength-shifting-fibre detector. Software routines for further optimizations in spatial resolution and uniformity of response have been implemented and tested for 2D detectors. The methods and results are discussed in this manuscript. Full Article text
osi A study of stress, composition and grain interaction gradients in energy-dispersive X-ray stress analysis on materials with cubic symmetry By journals.iucr.org Published On :: 2024-06-07 The influence of various combinations of residual stress, composition and grain interaction gradients in polycrystalline materials with cubic symmetry on energy-dispersive X-ray stress analysis is theoretically investigated. For the evaluation of the simulated sin2ψ distributions, two different strategies are compared with regard to their suitability for separating the individual gradients. It is shown that the separation of depth gradients of the strain-free lattice parameter a0(z) from residual stress gradients σ(z) is only possible if the data analysis is carried out in section planes parallel to the surface. The impact of a surface layer z* that is characterized by a direction-dependent grain interaction model in contrast to the volume of the material is quantified by comparing a ferritic and an austenitic steel, which feature different elastic anisotropy. It is shown to be of minor influence on the resulting residual stress depth profiles if the data evaluation is restricted to reflections hkl with orientation factors Γhkl close to the model-independent orientation Γ*. Finally, a method is proposed that allows the thickness of the anisotropic surface layer z* to be estimated on the basis of an optimization procedure. Full Article text
osi Accurate space-group prediction from composition By journals.iucr.org Published On :: 2024-06-18 Predicting crystal symmetry simply from chemical composition has remained challenging. Several machine-learning approaches can be employed, but the predictive value of popular crystallographic databases is relatively modest due to the paucity of data and uneven distribution across the 230 space groups. In this work, virtually all crystallographic information available to science has been compiled and used to train and test multiple machine-learning models. Composition-driven random-forest classification relying on a large set of descriptors showed the best performance. The predictive models for crystal system, Bravais lattice, point group and space group of inorganic compounds are made publicly available as easy-to-use software downloadable from https://gitlab.com/vishsoft/cosy. Full Article text
osi distect: automatic sample-position tracking for X-ray experiments using computer vision algorithms By journals.iucr.org Published On :: 2024-10-30 Soft X-ray spectroscopy is an important technique for measuring the fundamental properties of materials. However, for measurements of samples in the sub-millimetre range, many experimental setups show limitations. Position drifts on the order of hundreds of micrometres during thermal stabilization of the system can last for hours of expensive beam time. To compensate for drifts, sample tracking and feedback systems must be used. However, in complex sample environments where sample access is very limited, many existing solutions cannot be applied. In this work, we apply a robust computer vision algorithm to automatically track and readjust the sample position in the dozens of micrometres range. Our approach is applied in a complex sample environment, where the sample is in an ultra-high vacuum chamber, surrounded by cooled thermal shields to reach sample temperatures down to 2.5 K and in the center of a superconducting split coil. Our implementation allows sample-position tracking and adjustment in the vertical direction since this is the dimension where drifts occur during sample temperature change in our setup. The approach can be easily extended to 2D. The algorithm enables a factor of ten improvement in the overlap of a series of X-ray absorption spectra in a sample with a vertical size down to 70 µm. This solution can be used in a variety of experimental stations, where optical access is available and sample access by other means is reduced. Full Article text
osi Synchrotron CT dosimetry for wiggler operation at reduced magnetic field and spatial modulation with bow tie filters By journals.iucr.org Published On :: 2024-10-22 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. Full Article text
osi Testing Finds 'Positive' Results for Base Metal Recoveries in Spain By www.streetwisereports.com Published On :: Tue, 05 Nov 2024 00:00:00 PST Emerita Resources Corp. (EMO:TSX.V; EMOTF:OTCQB; LLJA:FSE) announces results from a metallurgical testing program at its wholly-owned Iberian Belt West (IBW) project in Spain. Read why one expert says the company is in "the right place to be." Full Article EMO:TSX.V; EMOTF:OTCQB; LLJA:FSE
osi H.C. Wainwright & Co. Raises Price Target on Biotech Following Positive Regulatory Updates By www.streetwisereports.com Published On :: Wed, 23 Oct 2024 00:00:00 PST Source: Andrew Fein 10/23/2024 DBV Technologies SA (DBVT:NASDAQ) received a raised target price after it released long-awaited regulatory clarity regarding the path forward for its Viaskin Peanut patch.H.C. Wainwright & Co. analysts Andrew S. Fein, Matthew Caufield, Dr. Andres Y. Maldonado, and Dr. Ananda Ghosh, in a research report published on October 23, 2024, maintained a Buy rating on DBV Technologies SA (DBVT:NASDAQ) while raising their price target to US$7.00 from US$5.00. The report follows DBV's announcement of regulatory clarity regarding the path forward for its Viaskin Peanut patch. The analysts highlighted the significance of the FDA agreement, stating, "DBV Technologies has reached an agreement with the FDA regarding the regulatory pathway for the Viaskin Peanut patch in toddlers aged one to three, under the Accelerated Approval pathway." Regarding the company's development timeline, the analysts noted, "The Biologics License Application (BLA) submission for Viaskin Peanut in this age group is expected to be supported by positive efficacy and safety data from DBV's completed EPITOPE Phase 3 study, as well as additional safety data from the upcoming six-month COMFORT Toddlers supplemental safety study, which is expected to begin in 2Q25." The report emphasized the strength of DBV's regulatory position, stating, "The FDA has stated that DBV has already satisfied two of the three criteria: the product treats a serious condition, and the product candidate provides a meaningful advantage over available therapies." The analysts also highlighted progress in Europe, noting, "The EMA confirmed that the successfully completed EPITOPE Phase 3 efficacy and safety trial in the one to three-year-old population, along with positive results from the VITESSE study in the four to seven-year-old population, and a new safety study using the modified circular patch in one to three-year-olds, could support an MAA for the one to seven-year-old indication with the modified patch." The analysts' valuation methodology for DBV Technologies is based on a composite approach. They explained, "Our US$7 price target is based on an equally weighted composite of: (a) US$5.10/share, as a 20x multiple of taxed and diluted FY34 GAAP EPS of US$5.13 discounted back to FY24 at 35%; and (b) an NPV of US$8.52/share with a 13% discount rate and 1% growth rate." The report included commercial projections, with the analysts stating, "We continue to model initial approval in 2027, with projected initial sales of US$17.5M, growing to US$1,182.8M by 2034." The analysts also outlined several risk factors, including potential clinical study failures, regulatory approval challenges, and market size uncertainties. In conclusion, H.C. Wainwright & Co.'s increased price target to US$7 reflects growing confidence in DBV Technologies' regulatory pathway for the Viaskin Peanut patch. The share price at the time of the report of US$0.70 represents a potential return of approximately 900% to the analysts' target price, highlighting the significant upside potential if the company successfully navigates the regulatory process and commercializes its product. Sign up for our FREE newsletter at: www.streetwisereports.com/get-newsImportant Disclosures: This article does not constitute investment advice and is not a solicitation for any investment. 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osi Biotech Shares Positive Phase I Data for Alzheimer's Treatment By www.streetwisereports.com Published On :: Thu, 31 Oct 2024 00:00:00 PST Source: Dr. Douglas Loe 10/31/2024 Leede Financial Inc.'s target price on ProMIS Neurosciences Inc. (PMN:TSX; PMN:NCM) reflects a potential return of 822%.Leede Financial analysts Dr. Douglas Loe and Siew Ching Yeo, in a research report published on October 30, 2024, maintained their Speculative Buy rating on ProMIS Neurosciences Inc. (PMN:TSX; PMN:NCM) with a price target of US$9.50. The report follows ProMIS's presentation of interim Phase I data for PMN310, its Alzheimer's disease (AD) candidate, at the Clinical Trials on Alzheimer's Disease (CTAD) conference. The analysts highlighted the positive safety and pharmacokinetic (PK) data, stating, "We were encouraged (though not overly surprised) to see that the mAb was well-tolerated at all five test doses ranging from 2.5mg/kg-to-40mg/kg." They added, "PK analysis of all of these patient cohorts in this single-ascending dose (SAD) trial suggests that once-monthly dosing may be sufficient to sustain mAb levels both in plasma and in cerebrospinal fluid over time." Regarding dosing efficacy, the analysts noted, "Importantly, ProMIS indicated in the Jul/24 update that even at 2.5mg/kg dosing, PMN310 levels in CSF were over 100x higher than predicted to be necessary to bind to all beta-amyloid oligomers that could accumulate in CSF in diseased patients." The analysts emphasized the significance of recent industry developments, particularly AbbVie's acquisition of Aliada Therapeutics, stating, "AbbVie's tangible interest in Phase I-stage AD assets shows us that ProMIS could itself be attractive to future suitors if/when it can document direct impact on cognitive impairment in diseased patients." The report highlighted ProMIS's financial position following its recent equity offering, noting that the company raised US$30.3M with multiple layers of warrant coverage tied to development milestones. Leede Financial's valuation methodology combines multiple approaches. The analysts explained, "We are maintaining our Speculative Buy rating and one-year PT of US$9.50 on PMN, with our valuation still based on NPV (30% discount rate) and multiples of our F2029 EBITDA/fd EPS forecasts." They added, "By direct comparison to Aliada's US$1.4B value, PMN shares would notionally be valued on a fully-diluted basis at US$17.65/shr." In conclusion, Leede Financial's maintenance of their Speculative Buy rating and US$9.50 price target reflects confidence in ProMIS's development of PMN310 and its potential in the Alzheimer's disease market. The share price at the time of the report of US$1.03 represents a potential return of approximately 822% to the analysts' target price, highlighting the significant upside potential if the company's clinical development plans prove successful. Sign up for our FREE newsletter at: www.streetwisereports.com/get-newsImportant Disclosures: As of the date of this article, officers and/or employees of Streetwise Reports LLC (including members of their household) own securities of ProMIS Neurosciences Inc. 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. This article does not constitute medical advice. Officers, employees and contributors to Streetwise Reports are not licensed medical professionals. Readers should always contact their healthcare professionals for medical advice. For additional disclosures, please click here. Disclosures for Leede Financial Inc., ProMIS Neurosciences Inc., October 30, 2024 Important Information and Legal Disclaimers Leede Financial Inc. (Leede) is a member of the Canadian Investment Regulatory Organization (CIRO) and a member of the Canadian Investor Protection Fund (CIPF). This document is not an offer to buy or sell or a solicitation of an offer to buy or sell any security or instrument or to participate in any particular investing strategy. 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Leede is registered and regulated by the Canadian Investment Regulatory Organization (CIRO) and is a member of the Canadian Investor Protection Fund (CIPF). Canadian clients wishing to effect transactions in any designated investment discussed should do so through a Leede Registered Representative. U.S. Disclosures This research report was prepared by Leede Financial Inc. (Leede). Leede is registered and regulated by the Canadian Investment Regulatory Organization (CIRO) and is a member of the Canadian Investor Protection Fund (CIPF). This report does not constitute an offer to sell or the solicitation of an offer to buy any of the securities discussed herein. Leede is not registered as a broker-dealer in the United States and is not subject to U.S. rules regarding the preparation of research reports and the independence of research analysts. Any resulting transactions should be effected through a U.S. broker-dealer. ( Companies Mentioned: PMN:TSX; PMN:NCM, ) Full Article
osi Revolutionary AI Tools Take Center Stage in Medical Education Symposium By www.streetwisereports.com Published On :: Tue, 05 Nov 2024 00:00:00 PST Source: Streetwise Reports 11/05/2024 Treatment.com AI Inc. (TRUE:CSE; TREIF:OTCMKTS; 939:FRA) has announced the release of its newly updated Medical Education Suite (MES). Read more to find out how this update is set to transform medical education and enhance training efficiency. Treatment.com AI Inc. (TRUE:CSE; TREIF:OTCMKTS; 939:FRA) has announced the release of its newly updated Medical Education Suite (MES). This release aligns with the company's active participation in a major symposium focused on AI assessment in medical education. The Symposium, hosted by the University of Minnesota Medical School, drew thought leaders and representatives from over 50 medical schools and national education organizations across the United States and internationally. The updated MES has been designed to leverage Treatment's proprietary Global Library of Medicine (GLM) to help reduce the administration overhead and associated time and costs for medical schools in running key exams, such as the Objective Structured Clinical Examination (OSCE). Additionally, this updated version of the MES includes "easy to use" features to further support students in their clinical assessment training and exam preparation. This OSCE exam is seen as a critical evaluation used globally to assess the practical skills of medical students. It is now employed in more than 80 countries, with between 200,000 to 300,000 students participating annually.1 The MES incorporates various AI-driven features, such as automated case generation for OSCE exams, scripts for simulated patients, and instant scoring with personalized feedback. The Suite also introduces new tools, including AI Patient, which supports students preparing for medical exams, and expanded OSCE case packages, which are expected to grow to a library of 100 cases by the end of Q4 2024. Additionally, the AI Prep Tool offers both non-guided and guided exam-simulated modes, assisting students in honing their clinical reasoning. Kevin Peterson, MD, MPH, Treatment's Chief Medical Officer, delivered a keynote at the Symposium, joining an impressive lineup that includes presenters from Mayo Clinic and the University of Alberta. The company highlights that this Symposium is a crucial opportunity to demonstrate its MES and showcase its growing influence in the field of medical education. CEO Dr. Essam Hamza emphasized the significance of this event, stating in the press release, "We are excited to showcase our updated medical education software suite at this landmark Symposium. The opportunity to have a positive impact on the medical training of students and, in turn, introduce them to our range of proprietary AI tools is an important inflection point in the company's commercialization timeline." AI in Healthcare On October 10, Microsoft emphasized the importance of multimodal AI models for a comprehensive assessment of patient health. The report highlighted the growing importance of using AI to analyze complex, multimodal health data, such as medical imaging, genomics, and clinical records. The integration of these data sources has enabled more precise diagnostics and treatment planning, illustrating the sector's move toward comprehensive AI applications. The healthcare industry has faced challenges like the need for large-scale, integrated datasets and significant computational resources, but advancements have begun to bridge these gaps. Microsoft noted that these developments would help unlock new insights and improve patient care by accelerating innovation and enhancing clinical decision-making across the sector. On November 4, Forbes reported that AI-powered healthcare tools were no longer merely experimental but were instead delivering real value across the industry. Examples included enhanced diagnostic accuracy through AI algorithms, like those developed by Google Cloud Healthcare, and improved administrative processes through platforms like Cedar's AI-powered billing system. Forbes noted that these developments were reshaping patient care and reducing administrative burdens, offering measurable benefits. Also, on November 4, Tech Target highlighted the optimism among healthcare professionals regarding generative AI's potential to alleviate administrative burdens. Over 90% of healthcare workers surveyed expressed confidence in generative AI's ability to simplify tasks like prior authorizations and nurse handoff reports. Aashima Gupta from Google Cloud shared insights on these tools' transformative capabilities, while Tony Farah from Highmark Health cited an 85% reduction in provider administrative costs after automating prior authorizations. Helen Waters from Meditech added, "We believe that gen AI and AI overall is transforming how healthcare professionals access and use information to make powerful decisions confidently," reflecting the positive impact of AI tools on healthcare workflows and decision-making. Company Catalysts Treatment.com AI Inc. continues to evolve its medical education platform, incorporating advanced AI technologies that could help revolutionize medical education and training. The company is leveraging its Global Library of Medicine, which offers over 10,000 medical reviews and covers more than 1,000 diseases and associated symptoms. These AI-driven tools aim to enhance clinical decision-making while reducing administrative burdens for healthcare institutions. The updated MES is projected to impact medical training through its comprehensive and AI-enhanced features, as outlined in Treatment's investor presentation. The presentation details the significant market potential, with the AI healthcare market expected to grow from US$11 billion in 2021 to US$187 billion by 2030, according to Statista. In addition to Treatment's announced new functionality, the company has already begun work on further solutions such as AI Doctor in a Pocket and audio/video analysis tools for clinical scoring and diagnostics. The goal of this expanded portfolio is to position the company to help expedite its aggressive growth plans over the next year. Analysis of Treatment.com AI *On October 9, Technical Analyst Clive Maund described Treatment.com AI Inc. as a "Strong Buy." He emphasized the company's potential to revolutionize the healthcare industry. [OWNERSHIP_CHART-10594] Maund also highlighted that Treatment AI was "centrally positioned" to capitalize on the expected massive growth in the AI healthcare market. The research note also mentioned the company's platform, powered by its proprietary Global Library of Medicine, as having wide-ranging attributes that could make "sweeping and positive changes" in healthcare, enhancing efficiency and reducing administrative burdens for healthcare professionals. Ownership and Share Structure According to Sedi.ca, insiders own approximately 8% of Treatment.com AI. Retail investors own the remaining 92%. The company has 48.99 million outstanding common shares and has 41.3 million free float traded shares. As of November 4, the market cap is approximately CA$31.35 million. Over the past 52 weeks, the company traded between CA$0.355 and CA$1.11 per share. 1Source bodies including: https://www.aamc.org/; https://www.uems.eu/; https://www.nmc.org.in/; Education – GMC (gmc-uk.org) Sign up for our FREE newsletter at: www.streetwisereports.com/get-newsImportant Disclosures: Treatment.com AI 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. As of the date of this article, officers and/or employees of Streetwise Reports LLC (including members of their household) own securities of Treatment.com AI. James Guttman wrote this article for Streetwise Reports LLC and provides services to Streetwise Reports as an employee. 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. This article does not constitute medical advice. Officers, employees and contributors to Streetwise Reports are not licensed medical professionals. Readers should always contact their healthcare professionals for medical advice. For additional disclosures, please click here. * Disclosure for the quote from the Clive Maund article published on [Date] For the quoted article (published on [Date]), the Company has paid Street Smart, an affiliate of Streetwise Reports, between US$1,500 and US$2,500. Author Certification and Compensation: [Clive Maund of clivemaund.com] is being compensated as an independent contractor by Street Smart, an affiliate of Streetwise Reports, for writing the article quoted. Maund received his UK Technical Analysts’ Diploma in 1989. The recommendations and opinions expressed in the article accurately reflect the personal, independent, and objective views of the author regarding any and all of the designated securities discussed. No part of the compensation received by the author was, is, or will be directly or indirectly related to the specific recommendations or views expressed Clivemaund.com Disclosures The quoted article represents the opinion and analysis of Mr. Maund, based on data available to him, at the time of writing. Mr. Maund's opinions are his own, and are not a recommendation or an offer to buy or sell securities. As trading and investing in any financial markets may involve serious risk of loss, Mr. Maund recommends that you consult with a qualified investment advisor, one licensed by appropriate regulatory agencies in your legal jurisdiction and do your own due diligence and research when making any kind of a transaction with financial ramifications. Although a qualified and experienced stock market analyst, Clive Maund is not a Registered Securities Advisor. Therefore Mr. Maund's opinions on the market and stocks cannot be only be construed as a recommendation or solicitation to buy and sell securities. 1Source bodies including: https://www.aamc.org/; https://www.uems.eu/; https://www.nmc.org.in/; Education – GMC (gmc-uk.org) ( Companies Mentioned: TRUE:CSE; TREIF:OTCMKTS;939:FRA, ) Full Article
osi Annual financial report for Fiscal Year 2012-2013 shows County improved financial position with conservative approach By www.catawbacountync.gov Published On :: Tue, 3 Dec 2013 09:35:00 EST Annual Financial Report for Fiscal Year 2012-2013 shows Catawba County improved its financial position with conservative approach. Full Article News Release FYI Public Notice
osi Events Preceding Deepwater Horizon Explosion and Oil Spill Point to Failure to Account for Safety Risks and Potential Dangers By Published On :: Wed, 17 Nov 2010 06:00:00 GMT The numerous technical and operational breakdowns that contributed to the Deepwater Horizon oil rig explosion and spill from the Macondo well in the Gulf of Mexico suggest the lack of a suitable approach for managing the inherent risks. Full Article
osi Chronic Fatigue Syndrome/Myalgic Encephalomyelitis Is a Legitimate Disease That Needs Proper Diagnosis and Treatment, Says IOM Report Identifies Five Symptoms to Diagnose Disease By Published On :: Tue, 10 Feb 2015 05:00:00 GMT Myalgic Encephalomyelitis/Chronic Fatigue Syndrome -- commonly referred to as ME/CFS -- is a legitimate, serious, and complex systemic disease that frequently and dramatically limits the activities of affected individuals, says a new report from the Institute of Medicine. Full Article
osi New Report Recommends Priority Actions to Achieve Global Health Security, Protect U.S. Position as Global Health Leader By Published On :: Mon, 15 May 2017 05:00:00 GMT A new report from the National Academies of Sciences, Engineering, and Medicine identifies global health priorities in light of current and emerging challenges and makes 14 recommendations for the U.S. government and other stakeholders to address these challenges, while maintaining U.S. status as a world leader in global health. Full Article
osi New Report Calls on Federal and State Collaboration to Address Brucellosis Transmission From Elk By Published On :: Wed, 31 May 2017 05:00:00 GMT Efforts to control brucellosis in the Greater Yellowstone Area (GYA) should focus on reducing the risk of transmission from elk, which are now viewed as the primary source of the infection in new cases occurring in cattle and domestic bison, says a new report by the National Academies of Sciences, Engineering, and Medicine. Full Article
osi New Report Calls for Greater Oversight of Precursor Chemicals Sold At the Retail Level to Reduce Threats from Improvised Explosive Devices By Published On :: Tue, 14 Nov 2017 06:00:00 GMT Policymakers’ efforts to reduce threats from improvised explosive devices (IEDs) should include greater oversight of precursor chemicals sold at the retail level – especially over the Internet – that terrorists, violent extremists, or criminals use to make homemade explosives, says a new report from the National Academies of Sciences, Engineering, and Medicine. Full Article
osi Minority-Serving Colleges and Universities Are Positioned to Serve as a Greater Resource for Meeting U.S. STEM Workforce Needs, But Increased Attention and Investments Are Needed By Published On :: Thu, 13 Dec 2018 06:00:00 GMT Higher education leaders, policymakers, and the private sector should take a range of actions to strengthen STEM programs and degree attainment in the nation’s Minority Serving Institutions (MSIs), says a new report from the National Academies of Sciences, Engineering, and Medicine. Full Article
osi New Report Calls for Policies and Practices to Promote Positive Adolescent Development and Close the Opportunity Gap By Published On :: Thu, 16 May 2019 04:00:00 GMT The changes in brain structure and connectivity that occur between the ages of 10 and 25 present adolescents with unique opportunities for positive, life-shaping development, and for recovering from past adversity, says a new report from the National Academies of Sciences, Engineering, and Medicine. Full Article
osi Leading Voices Discuss the Future of U.S. Science Policy at Feb. 26 Symposium - Event Marks 75th Anniversary of Vannevar Bushs 1945 Report Science - The Endless Frontier By Published On :: Wed, 05 Feb 2020 05:00:00 GMT The National Academy of Sciences, in partnership with The Kavli Foundation and the Alfred P. Sloan Foundation, will host a symposium to consider the future of science in the U.S. and how it can best serve society in the 21st century. Full Article
osi “A deep curiosity about the world” By Published On :: Mon, 13 Jul 2020 04:00:00 GMT The ocean may have something to teach us about the pandemic we’re grappling with, according to oceanographer and National Academy of Sciences member Jody Deming. Deming is a member of the Ocean Memory Project — a collaboration of scientists, artists, and others who are exploring how changes over time are encoded into ocean “memories.” Full Article
osi Action Collaborative Releases Repository of Initiatives Aimed at Preventing Sexual Harassment in Higher Education By Published On :: Wed, 30 Sep 2020 04:00:00 GMT The Action Collaborative on Preventing Sexual Harassment in Higher Education, a group of over 60 colleges, universities, and research institutions working to prevent sexual harassment, has released a repository of information on their efforts, along with an annual report on the Action Collaborative’s activities. Full Article