Increasing the quality of seismic interpretation

Acknowledgments E. Macrae was funded by an NERC Open CASE Ph.D. award (NE/F013728/1) with Midland Valley Exploration Ltd. as the industry partner. We thank 763 geoscientists for their participation, and in particular, the REs who gave their time freely to the project. M. Scott (University of Glasgow, UK) is thanked for assisting with the statistical analysis. Four reviewers are thanked for their constructive comments that improved the manuscript.Peer reviewedPublisher PD

Genetic algorithm based approach of SRM current profiling for torque control and minimal copper losses

This paper presents a novel approach to current profiling for switched reluctance machines that eliminates torque ripple while inherently guaranteeing minimum copper losses, along with linear torque control. Minimization of copper losses increases machine efficiency, while eliminating torque ripple is the pre requisite for SRM use in applications such as traction vehicles. This paper presents theoretical optimal current profiles, initially without consideration of DC link voltage limitations. Utilizing a Genetic Algorithm in conjunction with current profiling limit envelopes, an optimized set of current profiles across the torque ripple free speed range of an exemplary 8/6 SRM is then created. The profiles characteristics are analyzed and compared with commonly used torque sharing function control to confirm the merits of the proposed method

A new torque ripple minimization approach for switched reluctance drives

This paper presents a new torque control function for torque ripple reduction in switched reluctance drives. The approach is based on the maximum utilization of available dc link voltage, extending the zero torque-ripple speed range. The approach is suitable for switched reluctance machines with any number of phases and stator/rotor poles. Soft switching control is deployed, which reduces switching losses. At any instant, only one phase current is controlled, significantly reducing the control complexity. Simulations are carried out on a four-phase 8/6, 4kW SRM in MATLAB/Simulink

Uncertainty in geoscience interpretation, statistical quantification of the factors that affect interpretational ability and their application to the oil and gas industry

Understanding the subsurface through geological modelling is extremely important to modern civilisation, e.g. the extraction of resources and the geological storage of wastes. Geological data are commonly sparse, with the result that geological models are under-constrained and multiple structural interpretations are often valid. Geoscientists are also affected by cognitive biases, so individual interpretations may not be equally likely. A better understanding of how geoscientists should be trained, and what interpretational approaches are most effective, is therefore required. An international sample of more than 700 geoscientists, with varying technical backgrounds, and experience levels, was collected. Six reference experts were then recruited to interpret the same seismic image, allowing a scoring system to be formed to evaluate respondents' interpretations. Statistical analysis of the sample showed that respondents' experience was more influential than their education and work environment in terms of producing a valid interpretation. However, interpretational techniques relating to 'thinking about geological time' were even more influential than respondents' experience. The fact that certain techniques were statistically significant in addition to respondents' experience shows that training is important regardless of experience level. In addition to the large sample, a separate workshop experiment, utilising a control group, was conducted with 49 industry geoscientists. Analysis of the data from the workshop identified a causal link between 'considering the geological evolution' and 'producing a valid interpretation'. Finally, based on the results, and the analysis of relevant literature, an interpretation workflow was derived for the oil and gas industry. The workflow mitigates cognitive biases, improves team work, validates multiple interpretations and captures interpreters' evolving assumptions. Thus, this research advances the understanding of how risk arising from uncertainty in geoscience interpretation can be mitigated, and how geoscience teaching and practice can be improved.Understanding the subsurface through geological modelling is extremely important to modern civilisation, e.g. the extraction of resources and the geological storage of wastes. Geological data are commonly sparse, with the result that geological models are under-constrained and multiple structural interpretations are often valid. Geoscientists are also affected by cognitive biases, so individual interpretations may not be equally likely. A better understanding of how geoscientists should be trained, and what interpretational approaches are most effective, is therefore required. An international sample of more than 700 geoscientists, with varying technical backgrounds, and experience levels, was collected. Six reference experts were then recruited to interpret the same seismic image, allowing a scoring system to be formed to evaluate respondents' interpretations. Statistical analysis of the sample showed that respondents' experience was more influential than their education and work environment in terms of producing a valid interpretation. However, interpretational techniques relating to 'thinking about geological time' were even more influential than respondents' experience. The fact that certain techniques were statistically significant in addition to respondents' experience shows that training is important regardless of experience level. In addition to the large sample, a separate workshop experiment, utilising a control group, was conducted with 49 industry geoscientists. Analysis of the data from the workshop identified a causal link between 'considering the geological evolution' and 'producing a valid interpretation'. Finally, based on the results, and the analysis of relevant literature, an interpretation workflow was derived for the oil and gas industry. The workflow mitigates cognitive biases, improves team work, validates multiple interpretations and captures interpreters' evolving assumptions. Thus, this research advances the understanding of how risk arising from uncertainty in geoscience interpretation can be mitigated, and how geoscience teaching and practice can be improved

Future translational applications from the contemporary genomics era: a scientific statement from the American Heart Association

The field of genetics and genomics has advanced considerably with the achievement of recent milestones encompassing the identification of many loci for cardiovascular disease and variable drug responses. Despite this achievement, a gap exists in the understanding and advancement to meaningful translation that directly affects disease prevention and clinical care. The purpose of this scientific statement is to address the gap between genetic discoveries and their practical application to cardiovascular clinical care. In brief, this scientific statement assesses the current timeline for effective translation of basic discoveries to clinical advances, highlighting past successes. Current discoveries in the area of genetics and genomics are covered next, followed by future expectations, tools, and competencies for achieving the goal of improving clinical care

The effect of pressure on the crystal structure of [Gd(PhCOO)(3)(DMF)](n) to 3.7 GPa and the transition to a second phase at 5.0 GPa

The effect of pressure on the crystal structure of the coordination polymer [Gd(PhCOO)(3)(DMF)](n) has been studied to 5.0 GPa. At ambient pressure the structure is tetragonal (space group P4(2)/n) with the polymers extending along the c-direction of the unit cell; successive Gd atoms are alternately bridged by four benzoates and by two benzoates; the coordination spheres of the metal atoms are completed by DMF ligands. This results in two different Gd center dot center dot center dot Gd repeats, measuring 3.8953(3) and 5.3062(3) angstrom, respectively. The polymer chains interact with each other via dispersion interactions, including a number of CH center dot center dot center dot pi contacts to phenyl rings in which the H center dot center dot center dot ring-centroid distances are 3.19 to 3.28 angstrom. Up to 3.7 GPa the crystal remains in a compressed form of its ambient-pressure phase. The a-axis shortens by 7.7%, and the c-axis by 2.9%, the difference reflecting the greater ease of compression along the crystallographic directions mediated by weak intermolecular interactions. At ambient pressure the Gd-O distances span 2.290(2)-2.559(2) angstrom, with an average of 2.39(3) angstrom. At 3.7 GPa the corresponding parameters are 2.259(3) to 2.509(4) and 2.36(3) angstrom. The Gd center dot center dot center dot Gd distances shortened by 0.0467(4) and 0.1851(4) angstrom, and the CH center dot center dot center dot pi distances span the range 2.76-2.90 angstrom. During compression a number of H center dot center dot center dot H contacts develop, the shortest measuring 1.84 angstrom at 3.7 GPa. On increasing the pressure to 5.0 GPa a phase transition occurred in which the shortest H center dot center dot center dot H contact is relieved by conversion of an edge-to-edge phenyl-phenyl contact into a pi center dot center dot center dot pi stacking interaction. The new phase is also tetragonal, space group P (4) over bar 4, the inversion symmetry present in phase-I being lost in phase-II. The phase transition allows more efficient packing of ligands, and while the a-axis decreases in length the c-axis increases. This leads to Gd center dot center dot center dot Gd distances of 3.8373(4) and 5.3694(4) angstrom, the latter being longer than at ambient pressure. Gd-O distances at 5.0 GPa span the range 2.265(5) to 2.516(5) angstrom, with a mean of 2.36(2) angstrom

High pressure studies of hydroxo-bridged Cu(II) dimers

A combination of high pressure single crystal X-ray diffraction and high pressure SQUID magnetometry has been used to study three hydroxo-bridged copper(II) dimers. [Cu-2(OH)(2)(H2O)(2)(tmen)(2)](ClO4)(2) (1; tmen = tetramethylethylenediamine), [Cu-2(OH)(2)(tben)(2)](ClO4)(2) (2; tben = di-(t)butylethylenediamine) and [Cu-2(OH)(2)(bpy)(2)](BF4)(2) (3; bpy = 2,2'-bipyridine) have been structurally determined to 2.5, 0.9 and 4.7 GPa, respectively. The application of hydrostatic pressure imposes significant distortions and modifications in the structures of all three complexes. This is particularly true of the bond distances and angles between the metal centres and the bridging hydroxo groups. Compound 1 undergoes a phase transition between 1.2 and 2.5 GPa caused by the loss of a coordinated water molecule. This leads to a loss of symmetry and dramatic changes in the molecular structure of the complex. The structural changes are manifested in changes in the magnetic behaviour of the complexes as seen in dc susceptibility measurements up to similar to 0.9 GPa for 1, 2 and 3: the exchange becomes less antiferromagnetic in 1 and 2 and more ferromagnetic in 3

Spectrum of neurodevelopmental disease associated with the GNAO1 guanosine triphosphate-binding region

Objective To characterize the phenotypic spectrum associated with GNAO1 variants and establish genotype-protein structure-phenotype relationships. Methods We evaluated the phenotypes of 14 patients with GNAO1 variants, analyzed their variants for potential pathogenicity, and mapped them, along with those in the literature, on a three-dimensional structural protein model. Results The 14 patients in our cohort, including one sibling pair, had 13 distinct, heterozygous GNAO1 variants classified as pathogenic or likely pathogenic. We attributed the same variant in two siblings to parental mosaicism. Patients initially presented with seizures beginning in the first 3 months of life (8/14), developmental delay (4/14), hypotonia (1/14), or movement disorder (1/14). All patients had hypotonia and developmental delay ranging from mild to severe. Nine had epilepsy, and nine had movement disorders, including dystonia, ataxia, chorea, and dyskinesia. The 13 GNAO1 variants in our patients are predicted to result in amino acid substitutions or deletions in the GNAO1 guanosine triphosphate (GTP)-binding region, analogous to those in previous publications. Patients with variants affecting amino acids 207-221 had only movement disorder and hypotonia. Patients with variants affecting the C-terminal region had the mildest phenotypes.