Position-dependent mass Schrödinger equation for exponential-type potentials

In quantum chemical calculations, there are two facts of particular relevance: the position-dependent mass Schrödinger equation (PDMSE) and the exponential-type potentials used in the theoretical study of vibrational properties for diatomic molecules. Accordingly, in this work, the treatment of exactly solvable PDMSE for exponential-type potentials is presented. The proposal is based on the exactly solvable constant mass Schrödinger equation (CMSE) for a class of multiparameter exponential-type potentials, adapted to the position-dependent-mass (PDM) kinetic energy operator in the O von Roos formulation. As a useful application, we consider a PDM distribution of the form [Formula: see text], where the different parameters can be adjusted depending on the potential under study. The principal advantage of the method is that solution of different specific PDM exponential potential models are obtained as particular cases from the proposal by means of a simple choice of the involved exponential parameters. This means that is not necessary resort to specialized methods for solving second-order differential equations as usually done for each specific potential. Also, the usefulness of our results is shown with the calculation of s-waves scattering cross-section for the Hulthén potential although this kind of study can be extended to other specific potential models such as PDM deformed potentials.

Correction: IQSEC2-related encephalopathy in males and females: a comparative study including 37 novel patients

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Abstract P5-13-05: Overcoming barriers to achieve a successful breast cancer patient recruitment: Professionals' views

Accurate recruitment in performing clinical trials is crucial to avoid delays in the availability of potential beneficial treatments for patients. However, optimal strategies to improve it remain elusive and highly variable. The aim of this study was to identify the factors affecting recruitment from a multi-professional approach.

Methods: A convergent mixed method study was used, including key informant in-depth interviews (n=13), 5 focus groups (n=40) and a 209-item Likert-scale survey for the measurement of a whole array of variables of interest (i.e. job attitudes, job satisfaction, job stressors and social status). A purposive sample of professionals from thirty-three clinical trial sites in Spain were targeted. Qualitative data were analyzed alongside quantitative data to document patterns and modifiers of recruitment performance. Audio material was recorded, transcribed verbatim and analyzed using the framework method.

Findings: Pattern observed in qualitative data was confirmed in quantitative analysis. A total of 32 key barriers to successful patient recruitment were identified and clustered in three categories. The most commonly reported barriers and facilitators regarding a multifactorial approach were: System/organization: Counting on experienced recruiters and having a strong team-workforce awareness (92,3%); automated recruitment software, scientific culture, recruiting philosophy, adequate workload demands (88%); high stimuli and interprofessional trust (84%). However, lack of time devoted to clinical research in favor of assistance demands, excessive workload and bureaucratic tasks were the most salient stressors to fulfill professional research and recruitment responsibilities (54%). Working team conditions: Insufficient workforce support as well as high employee turnover contributed to emotional exhaustion and depersonalization and to a lower personal accomplishment (15%). Interpersonal relations affected not only motivation and performance but professionalism satisfaction with outcomes. Professional recruiter characteristics: Professionals with a high level of expertise and academic specialization (>5 years), greater active involvement in relevant clinical trials just as interprofessional prestige and recognition showed a greater satisfaction. Consequently, they were prompted to intensify their efforts to fulfill recruitment. The more effective clinical research settings were those better aligned with attributes for becoming high recruiters and with better multi-professional articulation. Suggestions to improve recruitment included providing professionals with devoted time for research, setting up collaborative research agreements, building a clinical research network, collaborative tumor registries, clinical trials data sharing resources, multidisciplinary functional units and committees, flexible staffing models and empowering oncologists/managers leadership.

Conclusions: This study provided useful understanding of how to maximize patient recruitment at clinical research sites. Strong team-workforce and adequate workload were the most important identified factors for achieving it. Results will be used to inform professionals and stakeholders of the next steps needed and to engage them to fulfill accurate recruitment.

Citation Format: Casas A, Gonzàlez X, Capelán M, Morales J, Fabián M, Ciruelos E, Gabriele G. Overcoming barriers to achieve a successful breast cancer patient recruitment: Professionals' views [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-13-05.

The new magnetic diagnostics in the WEST tokamak

The WEST tokamak consists of a major upgrade of the superconducting medium size tokamak Tore Supra aiming at testing ITER divertor components. Such modification has required rebuilding a full set of magnetic diagnostics. The project was started in 2013 and completed in 2016. The diagnostic consists of a set of 469 sensors (421 pick-up coils, 36 flux loops, and 12 Rogowski coils) installed in the WEST vacuum vessel. New analog integrators have been developed in order to obtain the magnetic field and flux from the raw signal of the sensors. During the startup phase of WEST, plasma currents of the order of a few kilo amperes were measured despite much larger current of the order of hundreds of kilo amperes flowing in nearby conducting structures. The diagnostic is now fully operational and exhibits a noise level of about 0.5 mT on the magnetic field, and 2.0 mWb on flux loops allowing identifying the plasma boundary with an accuracy of a few millimeters on a 2 ms time cycle.

IQSEC2-related encephalopathy in males and females: a comparative study including 37 novel patients

Purpose

Variants in IQSEC2, escaping X inactivation, cause X-linked intellectual disability with frequent epilepsy in males and females. We aimed to investigate sex-specific differences.

Methods

We collected the data of 37 unpublished patients (18 males and 19 females) with IQSEC2 pathogenic variants and 5 individuals with variants of unknown significance and reviewed published variants. We compared variant types and phenotypes in males and females and performed an analysis of IQSEC2 isoforms.

Results

IQSEC2 pathogenic variants mainly led to premature truncation and were scattered throughout the longest brain-specific isoform, encoding the synaptic IQSEC2/BRAG1 protein. Variants occurred de novo in females but were either de novo (2/3) or inherited (1/3) in males, with missense variants being predominantly inherited. Developmental delay and intellectual disability were overall more severe in males than in females. Likewise, seizures were more frequently observed and intractable, and started earlier in males than in females. No correlation was observed between the age at seizure onset and severity of intellectual disability or resistance to antiepileptic treatments.

Conclusion

This study provides a comprehensive overview of IQSEC2-related encephalopathy in males and females, and suggests that an accurate dosage of IQSEC2 at the synapse is crucial during normal brain development.

A standardized framework for representation of ancestry data in genomics studies, with application to the NHGRI-EBI GWAS Catalog

The accurate description of ancestry is essential to interpret, access, and integrate human genomics data, and to ensure that these benefit individuals from all ancestral backgrounds. However, there are no established guidelines for the representation of ancestry information. Here we describe a framework for the accurate and standardized description of sample ancestry, and validate it by application to the NHGRI-EBI GWAS Catalog. We confirm known biases and gaps in diversity, and find that African and Hispanic or Latin American ancestry populations contribute a disproportionately high number of associations. It is our hope that widespread adoption of this framework will lead to improved analysis, interpretation, and integration of human genomics data.

Recommendations for a nomenclature system for reporting methylation aberrations in imprinted domains

The analysis of DNA methylation has become routine in the pipeline for diagnosis of imprinting disorders, with many publications reporting aberrant methylation associated with imprinted differentially methylated regions (DMRs). However, comparisons between these studies are routinely hampered by the lack of consistency in reporting sites of methylation evaluated. To avoid confusion surrounding nomenclature, special care is needed to communicate results accurately, especially between scientists and other health care professionals. Within the European Network for Human Congenital Imprinting Disorders we have discussed these issues and designed a nomenclature for naming imprinted DMRs as well as for reporting methylation values. We apply these recommendations for imprinted DMRs that are commonly assayed in clinical laboratories and show how they support standardized database submission. The recommendations are in line with existing recommendations, most importantly the Human Genome Variation Society nomenclature, and should facilitate accurate reporting and data exchange among laboratories and thereby help to avoid future confusion.

Simultaneous recovery of Zn and Mn from used batteries in acidic and alkaline mediums: A comparative study

A parallel study of acidic and alkaline leaching for the recovery of Mn and Zn from spent alkaline batteries is outlined. Using H₂SO₄ as solvent and selecting appropriate conditions of temperature and concentration, all residues were dissolved except carbon. The separation and recovery of the two components were performed by electrodeposition with satisfactory results at pH values above 4 (current efficiency above 70% for Zn and Mn) but rather lower efficiencies as the pH decreased. Most of the Zn was selectively dissolved by alkaline leaching using a 6.5M NaOH solution, and its recovery was examined by means of both electrochemical and chemical processes. The expected formation of pure Zn by electrowinning failed due to the formation of ZnO, the content of which was highly dependent on the electrodeposition time. For short periods, Zn was the main component. For longer periods the electrodeposit consisted of agglomerated microparticles of ZnO with a minor fraction of Zn metal (barely 3% as measured by X-ray diffraction). A chemical reaction of the element with oxygen released at the anode surface might be responsible for its conversion to ZnO. A simple chemical route is described for the first time for the direct conversion of Zn(OH)₄^2- solution to nanostructured ZnO by lowering the pH to values around 12 using 2M HCl solution.