analysis Where are preschoolers active in childcare centers? A hot-spot analysis using GIS, GPS and accelerometry data. By ezproxy.scu.edu.au Published On :: Tue, 01 Aug 2023 00:00:00 -0400 Children's Geographies; 08/01/2023(AN 167303410); ISSN: 14733285Academic Search Premier Full Article PRESCHOOL children GLOBAL Positioning System PHYSICAL activity ACCELEROMETRY GEOGRAPHIC information systems PLAY environments CHILD care
analysis Analysis of accessibility to public schools with GIS: a case study of Salihli city (Turkey). By ezproxy.scu.edu.au Published On :: Thu, 01 Feb 2024 00:00:00 -0500 Children's Geographies; 02/01/2024(AN 175911759); ISSN: 14733285Academic Search Premier Full Article TURKEY PUBLIC schools SCHOOL administrators LOCAL transit access URBAN planners PRIMARY schools URBAN planning
analysis Talcott Parsons on building personality system theory via psychoanalysis By ifp.nyu.edu Published On :: Sun, 03 Nov 2024 22:24:26 +0000 The post Talcott Parsons on building personality system theory via psychoanalysis was curated by information for practice. Full Article History
analysis Estimation of the prevalence of anxiety during the COVID-19 pandemic: A meta-analysis of meta-analyses By ifp.nyu.edu Published On :: Mon, 28 Oct 2024 14:36:21 +0000 The post Estimation of the prevalence of anxiety during the COVID-19 pandemic: A meta-analysis of meta-analyses was curated by information for practice. Full Article Meta-analyses - Systematic Reviews
analysis The Use of Contribution Analysis in Evaluating Health Interventions: A Scoping Review By ifp.nyu.edu Published On :: Tue, 29 Oct 2024 02:32:33 +0000 Evaluation &the Health Professions, Ahead of Print. Contribution Analysis (CA) is a promising theory-based evaluation approach for complex interventions, yet its application in health interventions remains largely unexplored. To bridge this gap, we conducted a scoping review to examine the extent of such applications and the methodologies, strengths, and limitations of this approach in health […] The post The Use of Contribution Analysis in Evaluating Health Interventions: A Scoping Review was curated by information for practice. Full Article Meta-analyses - Systematic Reviews
analysis Managing low-level HIV viraemia in antiretroviral therapy: a systematic review and meta-analysis By ifp.nyu.edu Published On :: Tue, 29 Oct 2024 04:36:04 +0000 Objective HIV-1 management has advanced significantly with antiretroviral therapy (ART), yet challenges persist, including low-level HIV-1 viraemia (LLV). LLV presents a complex scenario, with varied definitions in the literature, reflecting uncertainties in its clinical interpretation. Questions arise regarding the underlying mechanisms of LLV, whether it signifies ongoing viral replication or stems from other factors. This […] The post Managing low-level HIV viraemia in antiretroviral therapy: a systematic review and meta-analysis was curated by information for practice. Full Article Meta-analyses - Systematic Reviews
analysis Social anxiety and bullying victimization: A three-level meta-analysis of cross-sectional and longitudinal studies By ifp.nyu.edu Published On :: Thu, 31 Oct 2024 01:10:58 +0000 Publication date: November 2024 Source: Child Abuse & Neglect, Volume 157 Author(s): Jiaqi Deng, Jiaqi Liu, Jianyu Luo, Yuhong Pi, Jiabing Pan, Zhongfang Fu, Xinfeng Tang Read the full article › The post Social anxiety and bullying victimization: A three-level meta-analysis of cross-sectional and longitudinal studies was curated by information for practice. Full Article Meta-analyses - Systematic Reviews
analysis Sleep and paranoia: A systematic review and meta-analysis By ifp.nyu.edu Published On :: Thu, 31 Oct 2024 03:21:12 +0000 Publication date: December 2024 Source: Clinical Psychology Review, Volume 114 Author(s): Poppy Brown, Sarah Reeve, Matthew Hotton, Natalie Steer, Craig Steel Read the full article › The post Sleep and paranoia: A systematic review and meta-analysis was curated by information for practice. Full Article Meta-analyses - Systematic Reviews
analysis How to improve group affirmation manipulations: A systematic review and meta-analysis By ifp.nyu.edu Published On :: Sat, 02 Nov 2024 05:43:15 +0000 Group Processes &Intergroup Relations, Ahead of Print. Researchers often ask participants to affirm positive aspects or shared values for a group important to them (a group affirmation manipulation) in order to encourage healthy behavior, acknowledge historical harm, accept group-based criticism, or diffuse the impact of social exclusion. An exploratory meta-analysis of 92 experiments that included […] The post How to improve group affirmation manipulations: A systematic review and meta-analysis was curated by information for practice. Full Article Meta-analyses - Systematic Reviews
analysis Avoiding the unwanted: A cross-cultural comprehensive analysis of experiential avoidance and a meta-analysis By ifp.nyu.edu Published On :: Sun, 03 Nov 2024 03:41:26 +0000 Publication date: October 2024 Source: Journal of Contextual Behavioral Science, Volume 34 Author(s): Sunkyung Yoon, Sooyeon Kim, Sinhae Cho, Hyewon Choi Read the full article › The post Avoiding the unwanted: A cross-cultural comprehensive analysis of experiential avoidance and a meta-analysis was curated by information for practice. Full Article Meta-analyses - Systematic Reviews
analysis Parent–child discrepancies in mate preferences: A three‐level meta‐analysis By ifp.nyu.edu Published On :: Sun, 03 Nov 2024 18:53:08 +0000 Abstract Through the lens of evolutional psychology, mate preferences are posited into a three “G” framework (good genes, good resources, and good persons/parents/partners) that captures genetic quality, resource acquisition, and personality and caregiving qualities. Previous research acknowledged that adult children had different mate preferences from their parents, but had no consensus on how such differences […] The post Parent–child discrepancies in mate preferences: A three‐level meta‐analysis was curated by information for practice. Full Article Meta-analyses - Systematic Reviews
analysis Clinical, Quality of Life, and Health Care Utilization Outcomes of Switching the Administration Route of Antipsychotic Medications Among People With Schizophrenia Spectrum Disorder: A Systematic Review and Meta-Analysis By ifp.nyu.edu Published On :: Mon, 04 Nov 2024 17:34:51 +0000 Journal of the American Psychiatric Nurses Association, Ahead of Print. Background:Using long-acting injectable (LAI) antipsychotic medications can improve the outcomes of patients with schizophrenia, such as reducing symptom severity and hospitalization risk. However, the outcomes of switching from oral to LAI antipsychotic medications are unclear.Aims:The purpose of this review is to provide a summary of […] The post Clinical, Quality of Life, and Health Care Utilization Outcomes of Switching the Administration Route of Antipsychotic Medications Among People With Schizophrenia Spectrum Disorder: A Systematic Review and Meta-Analysis was curated by information for practice. Full Article Meta-analyses - Systematic Reviews
analysis Prison Family Engagement Policies: A Multistate Systematic Review and Content Analysis By ifp.nyu.edu Published On :: Tue, 05 Nov 2024 03:32:08 +0000 The Prison Journal, Ahead of Print. Opportunities for incarcerated persons to connect with their loved ones exist in several forms. Yet, there is limited evidence documenting the scope of state prison family engagement policies beyond visitation. To fill this gap, a systematic policy review and content analysis of nine state prison family engagement policies was […] The post Prison Family Engagement Policies: A Multistate Systematic Review and Content Analysis was curated by information for practice. Full Article Meta-analyses - Systematic Reviews
analysis Notice of Special Interest (NOSI): Analysis of Existing Linked Datasets to Understand the Relationship between Housing Program Participation and Risk for Chronic Diseases and Other Conditions (R01-Clinical Trial Not Allowed) [First Available Due Date: Oct By ifp.nyu.edu Published On :: Sun, 20 Oct 2024 13:49:22 +0000 The post Notice of Special Interest (NOSI): Analysis of Existing Linked Datasets to Understand the Relationship between Housing Program Participation and Risk for Chronic Diseases and Other Conditions (R01-Clinical Trial Not Allowed) [First Available Due Date: Oct 07] was curated by information for practice. Full Article Funding
analysis Notice of Special Interest (NOSI): Analysis of Existing Linked Datasets to Understand the Relationship between Housing Program Participation and Risk for Chronic Diseases and Other Conditions (R01-Clinical Trial Not Allowed) By ifp.nyu.edu Published On :: Fri, 01 Nov 2024 03:23:01 +0000 The post Notice of Special Interest (NOSI): Analysis of Existing Linked Datasets to Understand the Relationship between Housing Program Participation and Risk for Chronic Diseases and Other Conditions (R01-Clinical Trial Not Allowed) was curated by information for practice. Full Article Funding
analysis Inclusion of unexposed clusters improves the precision of fixed effects analysis of stepped-wedge cluster randomized trials with binary and count outcomes By ifp.nyu.edu Published On :: Tue, 05 Nov 2024 07:02:04 +0000 The fixed effects model is a useful alternative to the mixed effects model for analyzing stepped-wedge cluster randomized trials (SW-CRTs). It controls for all time-invariant cluster-level confounders and has … Read the full article › The post Inclusion of unexposed clusters improves the precision of fixed effects analysis of stepped-wedge cluster randomized trials with binary and count outcomes was curated by information for practice. Full Article Open Access Journal Articles
analysis Factors associated with household willingness to pay for Universal Health Coverage in Cameroon: a nationwide cross-sectional analysis By ifp.nyu.edu Published On :: Tue, 05 Nov 2024 07:59:38 +0000 Sustained financing for Universal Health Coverage (UHC) has been a concern for the Cameroon government. Household contributions have been considered as a financing mechanism, but this raises concerns on the wi… Read the full article › The post Factors associated with household willingness to pay for Universal Health Coverage in Cameroon: a nationwide cross-sectional analysis was curated by information for practice. Full Article Open Access Journal Articles
analysis Staff Performance Analysis Engineer, Experienced Professionals, Cambridge, UK, Software Engineering By careers.peopleclick.com Published On :: Wednesday, October 14, 2020 8:07:02 AM EDT We are an Equal Opportunity Employer and do not discriminate against any employee or applicant for employment because of race, color, sex, age, national origin, religion, sexual orientation, gender identity, status as a veteran, and basis of disability or any other federal, state or local protected class. Are you highly inquisitive with a committed approach to improving performance? Do you want to make an impact on the future of Smartphone and Laptop computing? We are looking for experienced engineers with a strong understanding of computer architecture and performance analysis to investigate emerging use-cases such as AR and ML to help define future IP from Arm and our partners. About the role As a senior member of the engineering team within the Client Line of Business you will lead performance analysis investigations, producing data-led analysis and conclusions which help define requirements for future Client compute solutions. Client computing devices are expected to deliver incredible performance across an increasing range of diverse use cases including AAA quality gaming, compelling AR experiences and applications with deeply embedded AI and ML. You will use your knowledge of hardware and software to build a deep understanding of critical use cases. You will look at how workloads utilise available compute and memory resources, how advancements in SoC topologies, processor design and software will help improve user experience. Full Article
analysis Software Engineer - Debug and Performance Analysis Tools, Experienced Professionals, Cambridge, UK, Software Engineering By careers.peopleclick.com Published On :: Wednesday, October 21, 2020 8:24:08 AM EDT We are looking for an enthusiastic software developer with understanding of Java or modern C++, to join the Arm Mobile Studio team.The role involves collaborating with highly motivated developers from different backgrounds, and customers throughout the world, to craft the next generation of our performance analysis tools for Arm CPUs and Mali GPUs. As part of this team, you would help create new features, maintain existing ones, and support the engineering infrastructure for build, test, and continuous integration. We also help to support both internal and external customers, and contribute to our developer documentation, developer website, and community forums.We are growing the team to help deliver features that support the full breadth of Arm's product portfolio. Our tools are used to optimize the latest smart cars, drones, mobile games, and machine learning applications, your ideas will make a difference and help to bring world-beating products to market. Full Article
analysis Senior Software Engineer – HPC debug and analysis tools (Fixed Term Contract), Experienced Professionals, Warwick, UK, Software Engineering By careers.peopleclick.com Published On :: Tuesday, November 24, 2020 1:21:43 PM EST Please note this is a Fixed Term Contract ending Sept 2021 We are looking for a highly skilled, technically capable senior software engineer to join the team of Arm Forge at Warwick. You will be passionate about making a difference through building great quality products.As an experienced developer, you’ll have a methodical approach to debugging and performance analysis and understand how developers will use our tools to achieve their objectives. Working as part of a team of C++ software engineers based in Warwick you will help to develop the Arm Forge Debug and Profiling tools.Arm Forge is used by developers to increase software performance or fix software bugs from single Linux servers right up to the largest supercomputer on the planet. Our tools span a wide range of use cases; from C/C++/Python developers writing multithreaded server applications or ML and data analysis applications, to C/C++/Fortran/Python HPC developers scaling to millions of cores.To learn more about our group and the products please check https://developer.arm.com/hpc.Main DutiesWe are looking for a highly skilled and motivated senior software engineer who is passionate about producing quality valuable software to join our elite team based in Warwick.Responsible for developing quality functionality on schedule, including specification, design, development, documentation and test.Drive forward major features or improvements and increase quality into the product.Expected to integrate with existing ARM process and infrastructure where possible and use your experience to introduce new processes where required. Full Article
analysis Analysis of Ohio Advanced Practice Registered Nurses’ Rate of Prescribing Naltrexone for Patients With Alcohol Use Disorder Since Elimination of the X-Waiver By ifp.nyu.edu Published On :: Mon, 04 Nov 2024 21:29:54 +0000 Journal of the American Psychiatric Nurses Association, Ahead of Print. Background:Alcohol use disorder (AUD) is common and deadly. Naltrexone is a treatment for AUD. Previous research examined factors that predict Ohio Advanced Practice Registered Nurses’ (APRNs) utilization of naltrexone to treat AUD. Inclusion criteria included APRNs’ endorsing receipt of the X-waiver, a designation indicating providers’ […] The post Analysis of Ohio Advanced Practice Registered Nurses’ Rate of Prescribing Naltrexone for Patients With Alcohol Use Disorder Since Elimination of the X-Waiver was curated by information for practice. Full Article Journal Article Abstracts
analysis Retailers and malls embrace facial recognition and video analytics for enhanced security and footfall analysis By www.retailtechnologyreview.com Published On :: Sat, 13 Nov 1520 17:17:45 -0001 In the recent 2-3 years, an increasing number of malls and retail chains have adopted real-time video analytics and facial recognition to enhance security, customer experience and footfall analysis.Some of these technologies are showcased this week at the NRF Protect Conference in Long Beach, California. Full Article Data Capture Exhibitions and Events Surveillance and Security
analysis Automated selection of nanoparticle models for small-angle X-ray scattering data analysis using machine learning By journals.iucr.org Published On :: 2024-02-29 Small-angle X-ray scattering (SAXS) is widely used to analyze the shape and size of nanoparticles in solution. A multitude of models, describing the SAXS intensity resulting from nanoparticles of various shapes, have been developed by the scientific community and are used for data analysis. Choosing the optimal model is a crucial step in data analysis, which can be difficult and time-consuming, especially for non-expert users. An algorithm is proposed, based on machine learning, representation learning and SAXS-specific preprocessing methods, which instantly selects the nanoparticle model best suited to describe SAXS data. The different algorithms compared are trained and evaluated on a simulated database. This database includes 75 000 scattering spectra from nine nanoparticle models, and realistically simulates two distinct device configurations. It will be made freely available to serve as a basis of comparison for future work. Deploying a universal solution for automatic nanoparticle model selection is a challenge made more difficult by the diversity of SAXS instruments and their flexible settings. The poor transferability of classification rules learned on one device configuration to another is highlighted. It is shown that training on several device configurations enables the algorithm to be generalized, without degrading performance compared with configuration-specific training. Finally, the classification algorithm is evaluated on a real data set obtained by performing SAXS experiments on nanoparticles for each of the instrumental configurations, which have been characterized by transmission electron microscopy. This data set, although very limited, allows estimation of the transferability of the classification rules learned on simulated data to real data. Full Article text
analysis Bond topology of chain, ribbon and tube silicates. Part II. Geometrical analysis of infinite 1D arrangements of (TO4)n− tetrahedra By journals.iucr.org Published On :: 2024-04-29 In Part I of this series, all topologically possible 1-periodic infinite graphs (chain graphs) representing chains of tetrahedra with up to 6–8 vertices (tetrahedra) per repeat unit were generated. This paper examines possible restraints on embedding these chain graphs into Euclidean space such that they are compatible with the metrics of chains of tetrahedra in observed crystal structures. Chain-silicate minerals with T = Si4+ (plus P5+, V5+, As5+, Al3+, Fe3+, B3+, Be2+, Zn2+ and Mg2+) have a grand nearest-neighbour 〈T–T〉 distance of 3.06±0.15 Å and a minimum T⋯T separation of 3.71 Å between non-nearest-neighbour tetrahedra, and in order for embedded chain graphs (called unit-distance graphs) to be possible atomic arrangements in crystals, they must conform to these metrics, a process termed equalization. It is shown that equalization of all acyclic chain graphs is possible in 2D and 3D, and that equalization of most cyclic chain graphs is possible in 3D but not necessarily in 2D. All unique ways in which non-isomorphic vertices may be moved are designated modes of geometric modification. If a mode (m) is applied to an equalized unit-distance graph such that a new geometrically distinct unit-distance graph is produced without changing the lengths of any edges, the mode is designated as valid (mv); if a new geometrically distinct unit-distance graph cannot be produced, the mode is invalid (mi). The parameters mv and mi are used to define ranges of rigidity of the unit-distance graphs, and are related to the edge-to-vertex ratio, e/n, of the parent chain graph. The program GraphT–T was developed to embed any chain graph into Euclidean space subject to the metric restraints on T–T and T⋯T. Embedding a selection of chain graphs with differing e/n ratios shows that the principal reason why many topologically possible chains cannot occur in crystal structures is due to violation of the requirement that T⋯T > 3.71 Å. Such a restraint becomes increasingly restrictive as e/n increases and indicates why chains with stoichiometry TO<2.5 do not occur in crystal structures. Full Article text
analysis Multi-scale and time-resolved structure analysis of relaxor ferroelectric crystals under an electric field By journals.iucr.org Published On :: The electric field responses of the average and local lattice strains and polar nanoregions of relaxor ferroelectric PMN-30PT single crystals were revealed by multi-scale and time-resolved X-ray diffraction under DC and AC electric fields. Full Article text
analysis Real-time analysis of liquid-jet sample-delivery stability for an X-ray free-electron laser using machine vision By journals.iucr.org Published On :: This paper describes real-time statistical analysis of liquid jet images for SFX experiments at the European XFEL. This analysis forms one part of the automated jet re-alignment system for SFX experiments at the SPB/SFX instrument of European XFEL. Full Article text
analysis Advanced EXAFS analysis techniques applied to the L-edges of the lanthanide oxides By journals.iucr.org Published On :: The L-edge EXAFS of the entire set of lanthanide oxides were collected and modeled, taking into consideration the aggregation of inequivalent absorbing sites, geometric parameterization of the crystal lattice and multielectron excitation removal. Full Article text
analysis Multimodal reconstruction of TbCo thin-film structure with Bayesian analysis of polarized neutron reflectivity By journals.iucr.org Published On :: For the first time, a multimodal reconstruction of a magnetic thin-film structure has been found using polarised neutron reflectivity. This has been achieved by implementing the Bayesian approach in combination with error correction based on the maximum likelihood method and instrument function optimization. Full Article text
analysis Effect of thickness and noise on angular correlation analysis from scanning electron nanobeam diffraction of disordered carbon By journals.iucr.org Published On :: The impact of sample thickness and experimental noise on angular correlation analysis from scanning electron nanobeam diffraction patterns of disordered carbon are investigated and analyzed regarding the interpretability of the analysis results. Full Article text
analysis Crystal structure and Hirshfeld surface analysis of bis(benzoylacetonato)(ethanol)dioxidouranium(VI) By journals.iucr.org Published On :: In the complex, the ligand binds to the metal through an oxygen atom. The geometry of the seven-coordinate U atom is pentagonal bipyramidal, with the uranyl O atoms in apical positions. Full Article text
analysis Crystal structure and Hirshfeld-surface analysis of an etoxazole metabolite designated R13 By journals.iucr.org Published On :: The crystal structure of a metabolite of the insecticide/acaricide etoxazole, designated R13 is presented along with a Hirshfeld surface analysis of intermolecular interactions present in the crystal structure. Full Article text
analysis Crystal structure, Hirshfeld surface analysis, DFT and molecular docking studies of ethyl 5-amino-2-bromoisonicotinate By journals.iucr.org Published On :: Theoretical and experimental structural studies of the title compound were undertaken using X-ray and DFT methods. The interactions present in the crystal were analyzed using Hirshfeld surface and MEP surface analysis. Docking studies with a covid-19 main protease (PDB ID: 6LU7) as the target receptor indicate that the synthesized compound may be a potential candidate for pharmaceutical applications. Full Article text
analysis Synthesis, crystal structure and Hirshfeld surface analysis of N-(4-methoxyphenyl)picolinamide By journals.iucr.org Published On :: The molecular and crystal structure of N-(4-methoxyphenyl)picolinamide were studied and Hirshfeld surfaces and fingerprint plots were generated to investigate various intermolecular interactions. Full Article text
analysis Multi-scale and time-resolved structure analysis of relaxor ferroelectric crystals under an electric field By journals.iucr.org Published On :: 2024-10-29 Lead-based relaxor ferroelectrics exhibit giant piezoelectric properties owing to their heterogeneous structures. The average and local structures measured by single-crystal X-ray diffraction under DC and AC electric fields are reviewed in this article. The position-dependent local lattice strain and the distribution of polar nanodomains and nanoregions show strong electric field dependence, which contributes to the giant piezoelectric properties. Full Article text
analysis Crystal structure, Hirshfeld surface analysis, DFT and molecular docking studies of ethyl 5-amino-2-bromoisonicotinate By journals.iucr.org Published On :: 2024-11-08 In the title compound, C8H9BrN2O2, the C—O—C—C torsion angle between isonicotine and the ethyl group is 180.0 (2)°. Intramolecular N—H...O and C—H...O interactions consolidate the molecular structure. In the crystal, N—H...N interaction form S(5) zigzag chains along [010]. The most significant contributions to the Hirshfeld surface arise from H...H (33.2%), Br...H/H...Br (20.9%), O...H/H...O (11.2%), C...H/H...C (11.1%) and N...H/H...N (10%) contacts. The topology of the three-dimensional energy frameworks was generated using the B3LYP/6–31 G(d,p) model to calculate the total interaction energy. The net interaction energies for the title compound are Eele = 59.2 kJ mol−1, Epol = 15.5 kJ mol−1, Edis = 140.3 kJ mol−1 and Erep = 107.2 kJ mol−1 with a total interaction energy Etot of 128.8 kJ mol−1. The molecular structure was optimized by density functional theory (DFT) at the B3LYP/6–311+G(d,p) level and the theoretical and experimentally obtained parameters were compared. The frontier molecular orbitals HOMO and LUMO were generated, giving an energy gap ΔE of 4.0931 eV. The MEP was generated to identify active sites in the molecule and molecular docking studies carried out with the title compound (ligand) and the covid-19 main protease PDB ID: 6LU7, revealing a moderate binding affinity of −5.4 kcal mol−1. Full Article text
analysis Crystal structure and Hirshfeld-surface analysis of an etoxazole metabolite designated R13 By journals.iucr.org Published On :: 2024-11-08 The etoxazole metabolite R13, systematic name 4-(4-tert-butyl-2-ethoxyphenyl)-2-(2,6-difluorophenyl)oxazole (C21H21F2NO2), results from the oxidation of etoxazole, a chitin synthesis inhibitor belonging to the oxazoline class, widely used as an insecticide/acaricide since 1998. The structure of R13 features a central oxazole ring with attached 2,6-difluorophenyl and 4-t-butyl-2-ethoxyphenyl moieties. The overall conformation gives dihedral angles between these rings and the oxazole of 24.91 (5)° (with difluorophenyl) and 15.30 (6)° (with t-butyl-ethoxyphenyl), indicating an overall deviation from planarity. Additionally, torsion angles of the ethoxy and t-butyl groups define the orientation of these substituents relative to their benzene ring. In the crystal packing, no significant hydrogen bonds are present, but a Hirshfeld surface analysis highlights weak intermolecular contacts leading to π–π-stacked dimers linked by weak C—H...N contacts. The packing analysis confirms that most intermolecular interactions involve hydrogen atoms. Full Article text
analysis Development of dual-beamline photoelectron momentum microscopy for valence orbital analysis By journals.iucr.org Published On :: 2024-04-15 The soft X-ray photoelectron momentum microscopy (PMM) experimental station at the UVSOR Synchrotron Facility has been recently upgraded by additionally guiding vacuum ultraviolet (VUV) light in a normal-incidence configuration. PMM offers a very powerful tool for comprehensive electronic structure analyses in real and momentum spaces. In this work, a VUV beam with variable polarization in the normal-incidence geometry was obtained at the same sample position as the soft X-ray beam from BL6U by branching the VUV beamline BL7U. The valence electronic structure of the Au(111) surface was measured using horizontal and vertical linearly polarized (s-polarized) light excitations from BL7U in addition to horizontal linearly polarized (p-polarized) light excitations from BL6U. Such highly symmetric photoemission geometry with normal incidence offers direct access to atomic orbital information via photon polarization-dependent transition-matrix-element analysis. Full Article text
analysis Wavefront analysis and phase correctors design using SHADOW By journals.iucr.org Published On :: 2024-04-23 Knife-edge imaging is a successful method for determining the wavefront distortion of focusing optics such as Kirkpatrick–Baez mirrors or compound refractive lenses. In this study, the wavefront error of an imperfect elliptical mirror is predicted by developing a knife-edge program using the SHADOW/OASYS platform. It is shown that the focusing optics can be aligned perfectly by minimizing the parabolic and cubic coefficients of the wavefront error. The residual wavefront error provides precise information about the figure/height errors of the focusing optics suggesting it as an accurate method for in situ optical metrology. A Python program is developed to design a customized wavefront refractive corrector to minimize the residual wavefront error. Uniform beam at and out of focus and higher peak intensity are achieved by the wavefront correction in comparison with ideal focusing. The developed code provides a quick way for wavefront error analysis and corrector design for non-ideal optics especially for the new-generation diffraction-limited sources, and saves considerable experimental time and effort. Full Article text
analysis PEPICO analysis of catalytic reactor effluents towards quantitative isomer discrimination: DME conversion over a ZSM-5 zeolite By journals.iucr.org Published On :: 2024-06-25 The methanol-to-hydrocarbons (MTH) process involves the conversion of methanol, a C1 feedstock that can be produced from green sources, into hydrocarbons using shape-selective microporous acidic catalysts – zeolite and zeotypes. This reaction yields a complex mixture of species, some of which are highly reactive and/or present in several isomeric forms, posing significant challenges for effluent analysis. Conventional gas-phase chromatography (GC) is typically employed for the analysis of reaction products in laboratory flow reactors. However, GC is not suitable for the detection of highly reactive intermediates such as ketene or formaldehyde and is not suitable for kinetic studies under well defined low pressure conditions. Photoelectron–photoion coincidence (PEPICO) spectroscopy has emerged as a powerful analytical tool for unraveling complex compositions of catalytic effluents, but its availability is limited to a handful of facilities worldwide. Herein, PEPICO analysis of catalytic reactor effluents has been implemented at the FinEstBeAMS beamline of MAX IV Laboratory. The conversion of dimethyl ether (DME) on a zeolite catalyst (ZSM-5-MFI27) is used as a prototypical model reaction producing a wide distribution of hydrocarbon products. Since in zeolites methanol is quickly equilibrated with DME, this reaction can be used to probe vast sub-networks of the full MTH process, while eliminating or at least slowing down methanol-induced secondary reactions and catalyst deactivation. Quantitative discrimination of xylene isomers in the effluent stream is achieved by deconvoluting the coincidence photoelectron spectra. Full Article text
analysis MuscleX: data analysis software for fiber diffraction patterns from muscle By journals.iucr.org Published On :: 2024-07-30 MuscleX is an integrated, open-source computer software suite for data reduction of X-ray fiber diffraction patterns from striated muscle and other fibrous systems. It is written in Python and runs on Linux, Microsoft Windows or macOS. Most modules can be run either from a graphical user interface or in a `headless mode' from the command line, suitable for incorporation into beamline control systems. Here, we provide an overview of the general structure of the MuscleX software package and describe the specific features of the individual modules as well as examples of applications. Full Article text
analysis 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
analysis Crystal structures, electron spin resonance, and thermogravimetric analysis of three mixed-valence copper cyanide polymers By journals.iucr.org Published On :: 2024-05-01 The crystal structures of three mixed-valence copper cyanide alkanolamine polymers are presented, together with thermogravimetric analysis (TGA) and electron spin resonance (ESR) data. In all three structures, a CuII moiety on a crystallographic center of symmetry is coordinated by two alkanolamines and links two CuICN chains via cyanide bridging groups to form diperiodic sheets. The sheets are linked together by cuprophilic CuI–CuI interactions to form a three-dimensional network. In poly[bis(μ-3-aminopropanolato)tetra-μ-cyanido-dicopper(I)dicopper(II)], [Cu4(CN)4(C3H8NO)2]n, 1, propanolamine bases have lost their hydroxyl H atoms and coordinate as chelates to two CuII atoms to form a dimeric CuII moiety bridged by the O atoms of the bases with CuII atoms in square-planar coordination. The ESR spectrum is very broad, indicating exchange between the two CuII centers. In poly[bis(2-aminopropanol)tetra-μ-cyanido-dicopper(I)copper(II)], [Cu3(CN)4(C3H9NO)2]n, 2, and poly[bis(2-aminoethanol)tetra-μ-cyanido-dicopper(I)copper(II)], [Cu3(CN)4(CH7NO)2]n, 3, a single CuII atom links the CuICN chains together via CN bridges. The chelating alkanolamines are not ionized, and the OH groups form rather long bonds in the axial positions of the octahedrally coordinated CuII atoms. The coordination geometries of CuII in 2 and 3 are almost identical, except that the Cu—O distances are longer in 2 than in 3, which may explain their somewhat different ESR spectra. Thermal decomposition in 2 and 3, but not in 1, begins with the loss of HCN(g), and this can be correlated with the presence of OH protons on the ligands in 2 and 3, which are not present in 1. Full Article text
analysis Synthesis, characterization and structural analysis of complexes from 2,2':6',2''-terpyridine derivatives with transition metals By journals.iucr.org Published On :: 2024-05-16 The synthesis and structural characterization of three families of coordination complexes synthesized from 4'-phenyl-2,2':6',2''-terpyridine (8, Ph-TPY), 4'-(4-chlorophenyl)-2,2':6',2''-terpyridine (9, ClPh-TPY) and 4'-(4-methoxyphenyl)-2,2':6',2''-terpyridine (10, MeOPh-TPY) ligands with the divalent metals Co2+, Fe2+, Mn2+ and Ni2+ are reported. The compounds were synthesized from a 1:2 mixture of the metal and ligand, resulting in a series of complexes with the general formula [M(R-TPY)2](ClO4)2 (where M = Co2+, Fe2+, Mn2+ and Ni2+, and R-TPY = Ph-TPY, ClPh-TPY and MeOPh-TPY). The general formula and structural and supramolecular features were determinated by single-crystal X-ray diffraction for bis(4'-phenyl-2,2':6',2''-terpyridine)nickel(II) bis(perchlorate), [Ni(C21H15N3)2](ClO4)2 or [Ni(Ph-TPY)2](ClO4)2, bis[4'-(4-methoxyphenyl)-2,2':6',2''-terpyridine]manganese(II) bis(perchlorate), [Mn(C22H17N3O)2](ClO4)2 or [Mn(MeOPh-TPY)2](ClO4)2, and bis(4'-phenyl-2,2':6',2''-terpyridine)manganese(II) bis(perchlorate), [Mn(C21H15N3)2](ClO4)2 or [Mn(Ph-TPY)2](ClO4)2. In all three cases, the complexes present distorted octahedral coordination polyhedra and the crystal packing is determined mainly by weak C—H⋯π interactions. All the compounds (except for the Ni derivatives, for which FT–IR, UV–Vis and thermal analysis are reported) were fully characterized by spectroscopic (FT–IR, UV–Vis and NMR spectroscopy) and thermal (TGA–DSC, thermogravimetric analysis–differential scanning calorimetry) methods. Full Article text
analysis Using cocrystals as a tool to study non-crystallizing molecules: crystal structure, Hirshfeld surface analysis and computational study of the 1:1 cocrystal of (E)-N-(3,4-difluorophenyl)-1-(pyridin-4-yl)methanimine and acetic By journals.iucr.org Published On :: 2024-07-05 Using a 1:1 cocrystal of (E)-N-(3,4-difluorophenyl)-1-(pyridin-4-yl)methanimine with acetic acid, C12H8F2N2·C2H4O2, we investigate the influence of F atoms introduced to the aromatic ring on promoting π–π interactions. The cocrystal crystallizes in the triclinic space group P1. Through crystallographic analysis and computational studies, we reveal the molecular arrangement within this cocrystal, demonstrating the presence of hydrogen bonding between the acetic acid molecule and the pyridyl group, along with π–π interactions between the aromatic rings. Our findings highlight the importance of F atoms in promoting π–π interactions without necessitating full halogenation of the aromatic ring. Full Article text
analysis Synthesis of organotin(IV) heterocycles containing a xanthenyl group by a Barbier approach via ultrasound activation: synthesis, crystal structure and Hirshfeld surface analysis By journals.iucr.org Published On :: 2024-07-25 A series of organotin heterocycles of general formula [{Me2C(C6H3CH2)2O}SnR2] [R = methyl (Me, 4), n-butyl (n-Bu, 5), benzyl (Bn, 6) and phenyl (Ph, 7)] was easily synthesized by a Barbier-type reaction assisted by the sonochemical activation of metallic magnesium. The 119Sn{1H} NMR data for all four compounds confirm the presence of a central Sn atom in a four-coordinated environment in solution. Single-crystal X-ray diffraction studies for 17,17-dimethyl-7,7-diphenyl-15-oxa-7-stannatetracyclo[11.3.1.05,16.09,14]heptadeca-1,3,5(16),9(14),10,12-hexaene, [Sn(C6H5)2(C17H16O)], 7, at 100 and 295 K confirmed the formation of a mononuclear eight-membered heterocycle, with a conformation depicted as boat–chair, resulting in a weak Sn⋯O interaction. The Sn and O atoms are surrounded by hydrophobic C—H bonds. A Hirshfeld surface analysis of 7 showed that the eight-membered heterocycles are linked by weak C—H⋯π, π–π and H⋯H noncovalent interactions. The pairwise interaction energies showed that the cohesion between the heterocycles are mainly due to dispersion forces. Full Article text
analysis 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
analysis Structural analysis of a ligand-triggered intermolecular disulfide switch in a major latex protein from opium poppy By journals.iucr.org Published On :: 2024-08-29 Several proteins from plant pathogenesis-related family 10 (PR10) are highly abundant in the latex of opium poppy and have recently been shown to play diverse and important roles in the biosynthesis of benzylisoquinoline alkaloids (BIAs). The recent determination of the first crystal structures of PR10-10 showed how large conformational changes in a surface loop and adjacent β-strand are coupled to the binding of BIA compounds to the central hydrophobic binding pocket. A more detailed analysis of these conformational changes is now reported to further clarify how ligand binding is coupled to the formation and cleavage of an intermolecular disulfide bond that is only sterically allowed when the BIA binding pocket is empty. To decouple ligand binding from disulfide-bond formation, each of the two highly conserved cysteine residues (Cys59 and Cys155) in PR10-10 was replaced with serine using site-directed mutagenesis. Crystal structures of the Cys59Ser mutant were determined in the presence of papaverine and in the absence of exogenous BIA compounds. A crystal structure of the Cys155Ser mutant was also determined in the absence of exogenous BIA compounds. All three of these crystal structures reveal conformations similar to that of wild-type PR10-10 with bound BIA compounds. In the absence of exogenous BIA compounds, the Cys59Ser and Cys155Ser mutants appear to bind an unidentified ligand or mixture of ligands that was presumably introduced during expression of the proteins in Escherichia coli. The analysis of conformational changes triggered by the binding of BIA compounds suggests a molecular mechanism coupling ligand binding to the disruption of an intermolecular disulfide bond. This mechanism may be involved in the regulation of biosynthetic reactions in plants and possibly other organisms. Full Article text
analysis Analysis of crystallographic phase retrieval using iterative projection algorithms By journals.iucr.org Published On :: 2024-10-23 For protein crystals in which more than two thirds of the volume is occupied by solvent, the featureless nature of the solvent region often generates a constraint that is powerful enough to allow direct phasing of X-ray diffraction data. Practical implementation relies on the use of iterative projection algorithms with good global convergence properties to solve the difficult nonconvex phase-retrieval problem. In this paper, some aspects of phase retrieval using iterative projection algorithms are systematically explored, where the diffraction data and density-value distributions in the protein and solvent regions provide the sole constraints. The analysis is based on the addition of random error to the phases of previously determined protein crystal structures, followed by evaluation of the ability to recover the correct phase set as the distance from the solution increases. The properties of the difference-map (DM), relaxed–reflect–reflect (RRR) and relaxed averaged alternating reflectors (RAAR) algorithms are compared. All of these algorithms prove to be effective for crystallographic phase retrieval, and the useful ranges of the adjustable parameter which controls their behavior are established. When these algorithms converge to the solution, the algorithm trajectory becomes stationary; however, the density function continues to fluctuate significantly around its mean position. It is shown that averaging over the algorithm trajectory in the stationary region, following convergence, improves the density estimate, with this procedure outperforming previous approaches for phase or density refinement. Full Article text
analysis Orientational analysis of atomic pair correlations in nanocrystalline indium oxide thin films By journals.iucr.org Published On :: 2024-01-01 The application of grazing-incidence total X-ray scattering (GITXS) for pair distribution function (PDF) analysis using >50 keV X-rays from synchrotron light sources has created new opportunities for structural characterization of supported thin films with high resolution. Compared with grazing-incidence wide-angle X-ray scattering, which is only useful for highly ordered materials, GITXS/PDFs expand such analysis to largely disordered or nanostructured materials by examining the atomic pair correlations dependent on the direction relative to the surface of the supporting substrate. A characterization of nanocrystalline In2O3-derived thin films is presented here with in-plane-isotropic and out-of-plane-anisotropic orientational ordering of the atomic structure, each synthesized using different techniques. The atomic orientations of such films are known to vary based on the synthetic conditions. Here, an azimuthal orientational analysis of these films using GITXS with a single incident angle is shown to resolve the markedly different orientations of the atomic structures with respect to the planar support and the different degrees of long-range order, and hence, the terminal surface chemistries. It is anticipated that orientational analysis of GITXS/PDF data will offer opportunities to extend structural analyses of thin films by providing a means to qualitatively determine the major atomic orientation within nanocrystalline and, eventually, non-crystalline films. Full Article text
analysis Structural analysis of nanocrystals by pair distribution function combining electron diffraction with crystal tilting By journals.iucr.org Published On :: 2024-02-16 As an important characterization method, pair distribution function (PDF) has been extensively used in structural analysis of nanomaterials, providing key insights into the degree of crystallinity, atomic structure, local disorder etc. The collection of scattering signals with good statistics is necessary for a reliable structural analysis. However, current conventional electron diffraction experiments using PDF (ePDF) are limited in their ability to acquire continuous diffraction rings for large nanoparticles. Herein, a new method – tilt-ePDF – is proposed to improve the data quality and compatibility of ePDF by a combination of electron diffraction and specimen tilting. In the present work, a tilt-series of electron diffraction patterns was collected from gold nanoparticles with three different sizes and a standard sample polycrystalline aluminium film for ePDF analysis. The results show that tilt-ePDF can not only enhance the continuity of diffraction rings, but can also improve the signal-to-noise ratio in the high scattering angle range. As a result, compared with conventional ePDF data, tilt-ePDF data provide structure parameters with a better accuracy and lower residual factors in the refinement against the crystal structure. This method provides a new way of utilizing ePDF to obtain accurate local structure information from nanoparticles. Full Article text