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1.
Forensic Sci Int Genet ; 71: 103053, 2024 Apr 23.
Article En | MEDLINE | ID: mdl-38728819

The Forensic Databases Advisory Board (FDAB), an independent board that assists the International Society for Forensic Genetics (ISFG), has presented a First Report on ethical aspects of the following Forensic Genetic Frequency Databases (FGFD): EMPOP, STRidER and YHRD. The FDAB designed an ethical framework to evaluate the content of these FGFD, and the factors to be considered for retention and acceptance of submissions. The FDAB framework proposes to categorize submissions according to the risk of having contravened the universal ethical principles outlined by international organizations, and the guidelines adopted by the ISFG. The report has been open to discussion by the scientific community since 2023. Herein we present the conception and development of the First Report along with a summary of its content, with consideration of the feedback received.

2.
Science ; 363(6430): 938-940, 2019 03 01.
Article En | MEDLINE | ID: mdl-30819955
3.
Nat Commun ; 8(1): 1203, 2017 10 31.
Article En | MEDLINE | ID: mdl-29084943

The multifaceted character of 5f electrons in actinide materials, from localized to itinerant and in between, together with their complex interactions with 6d and other conduction electron states, has thwarted efforts for fully understanding this class of compounds. While theoretical efforts abound, direct experimental probes of relevant electronic states and their hybridization are limited. Here we exploit the presence of sizable quadrupolar and dipolar contributions in the uranium L3-edge X-ray absorption cross section to provide unique information on the extent of spin-polarized hybridization between 5f and 6d electronic states by means of X-ray magnetic circular dichroism. As a result, we show how this 5f-6d hybridization regulates the magnetism of each sublattice in UCu2Si2 and UMn2Si2 compounds, demonstrating the potentiality of this methodology to investigate a plethora of magnetic actinide compounds.

4.
Nat Commun ; 8: 16053, 2017 07 06.
Article En | MEDLINE | ID: mdl-28681848

One of the long standing debates in actinide chemistry is the level of localization and participation of the actinide 5f valence orbitals in covalent bonds across the actinide series. Here we illuminate the role of the 5f valence orbitals of uranium, neptunium and plutonium in chemical bonding using advanced spectroscopies: actinide M4,5 HR-XANES and 3d4f RIXS. Results reveal that the 5f orbitals are active in the chemical bonding for uranium and neptunium, shown by significant variations in the level of their localization evidenced in the spectra. In contrast, the 5f orbitals of plutonium appear localized and surprisingly insensitive to different bonding environments. We envisage that this report of using relative energy differences between the 5fδ/φ and 5fπ*/5fσ* orbitals as a qualitative measure of overlap-driven actinyl bond covalency will spark activity, and extend to numerous applications of RIXS and HR-XANES to gain new insights into the electronic structures of the actinide elements.

5.
Dalton Trans ; 45(36): 14035-8, 2016 Sep 28.
Article En | MEDLINE | ID: mdl-27541854

Mercury 5d-orbitals are involved in intramolecular π-interactions with carbon and sulfur nearest and next-nearest neighbors in mercury-aryl complexes. This unexpected character of the electron cloud of mercury was revealed by high energy-resolution XANES spectroscopy readily interpreted in terms of a final-state local (l,m)-projected density of states (DOS).

6.
J Phys Condens Matter ; 26(12): 125504, 2014 Mar 26.
Article En | MEDLINE | ID: mdl-24599265

Resonant diffraction of x-rays by crystals with anisotropic optical properties is investigated theoretically, to assess how the intensity of a Bragg spot is influenced by effects related to dispersion (birefringence) and absorption (dichroism). Starting from an exact but opaque expression, simple analytic results are found to expose how intensity depends on dispersion and absorption in the primary and secondary beams and, also, the azimuthal angle (rotation of the crystal about the Bragg wavevector). If not the full story for a given application, our results are more than adequate to explore consequences of dispersion and absorption in the intensity of a Bragg spot. Results are evaluated for antiferromagnetic copper oxide, and low quartz. For CuO, one of our results reproduces all salient features of a previously published simulation of the azimuthal-angle dependence of a magnetic Bragg peak. It is transparent in our analytic result that dispersion and absorption effects alone cannot reproduce published experimental data. Available data for the azimuthal-angle dependence of space-group forbidden reflections (0,0, l), with l ≠ 3n, of low quartz depart from symmetry imposed by the triad axis of rotation symmetry. The observed asymmetry can be induced by dispersion and absorption even though absorption coefficients are constant, independent of the azimuthal angle, in this class of reflections.


Copper/chemistry , Models, Chemical , Models, Molecular , Refractometry/methods , X-Ray Diffraction/methods , X-Rays , Absorption , Computer Simulation , Scattering, Radiation
7.
Public Health Genomics ; 16(6): 322-35, 2013.
Article En | MEDLINE | ID: mdl-24503593

BACKGROUND: Data sharing from clinical trials can be key to the development and approval of medicines for rare diseases. Many events during the first half of 2013 have contributed to the movement for increased transparency. These include the development of the European Medicines Agency's new data publication policy, the creation of the AllTrials petition and GlaxoSmithKline's choice to sign it, the launch of GlaxoSmithKline's system for access to patient-level clinical trial data and Roche's commitment to create a similar system, the release of results from the Yale University Open Data Access project's first medicine analysis for Medtronic, and the creation of the Reg4All website. AIMS/OBJECTIVES: This paper summarises major developments in clinical trial transparency between January and June 2013 and analyses the composition of datasets released by GlaxoSmithKline. METHODS: GlaxoSmithKline's database of available trials was tabulated and graphs of relevant trial characteristics were produced. RESULTS/CONCLUSIONS: Due to current transparency initiatives, it is likely that much more data will be made available over the next few years through systems similar to GlaxoSmithKline's. Although some aspects of GlaxoSmithKline's model could limit its usefulness, the data currently listed is diverse and could be promising for researchers interested in rare disease treatment.


Access to Information , Clinical Trials as Topic/standards , Disclosure , Drug Industry/organization & administration , Information Dissemination , Orphan Drug Production , Clinical Trials as Topic/ethics , Databases, Factual , Humans , Research Design
8.
J Phys Condens Matter ; 24(21): 215502, 2012 May 30.
Article En | MEDLINE | ID: mdl-22534142

We report the implementation of a fully relativistic time dependent density functional theory (TDDFT) method for carrying out x-ray absorption spectroscopy calculations for extended systems. This is the first time that a TDDFT simulation of x-ray absorption in extended systems has featured a full potential ground state calculation. We prove that this unusual feature of the TDDFT implementation unequivocally yields improvement over the previous muffin-tin calculation methods.


Models, Theoretical , Scattering, Radiation , Spectrometry, X-Ray Emission/methods , Absorption , Computer Simulation , X-Rays
9.
Phys Rev Lett ; 106(16): 167203, 2011 Apr 22.
Article En | MEDLINE | ID: mdl-21599408

Resonant magnetic x-ray scattering near the vanadium L2,3-absorption edges has been used to investigate the low temperature magnetic structure of high quality BaVS3 single crystals. Below T(N)=31 K, the strong resonance revealed a triple-incommensurate magnetic ordering at the wave vector (0.226   0.226   ξ) in hexagonal notation, with ξ=0.033. The azimuthal-angle dependence of the scattering signal and time-dependent density functional theory simulations indicate an antiferromagnetic order within the ab plane with the spins polarized along a in the monoclinic structure.

10.
Pharmacogenomics J ; 11(3): 155-61, 2011 Jun.
Article En | MEDLINE | ID: mdl-21445091

Although the scientific research surrounding pharmacogenomics (PGx) has been relatively plentiful, the ethical research concerning this discipline has developed rather conservatively. Following investigation of the ethical, legal and social issues (ELSI) of PGx research, as well as consulting with key stakeholders, we identified six outstanding ethical issues raised by the informed consent process in PGx research: (1) scope of consent; (2) consent to 'add-on' studies; (3) protection of personal information; (4) commercialization; (5) data sharing; and (6) potential risks stemming from population-based research. In discussing these six areas as well as offering specific considerations, this article offers a solid base from which future practical guidelines for informed consent in PGx research can be constructed. As such, this effort works toward filling the ELSI gap and provides ethical support to the numerous PGx projects undertaken by researchers every year.


Biomedical Research/ethics , Informed Consent/ethics , Pharmacogenetics/ethics , Confidentiality/ethics , Humans , Information Dissemination/ethics , Informed Consent/legislation & jurisprudence , Pharmacogenetics/economics , Pharmacogenetics/legislation & jurisprudence
11.
Phys Rev Lett ; 105(8): 087203, 2010 Aug 20.
Article En | MEDLINE | ID: mdl-20868129

We report the direct measurement of antiferromagnetic spin polarization at the oxygen sites in the multiferroic TbMn2O5, through resonant soft x-ray magnetic scattering. This supports recent theoretical models suggesting that the oxygen spin polarization is key to the magnetoelectric coupling mechanism. The spin polarization is observed through a resonantly enhanced diffraction signal at the oxygen K edge at the commensurate antiferromagnetic wave vector. Using the fdmnes code we have accurately reproduced the experimental data. We have established that the resonance arises through the spin polarization on the oxygen sites hybridized with the square based pyramid Mn3+ ions. Furthermore we have discovered that the position of the Mn3+ ion directly influences the oxygen spin polarization.

12.
Clin Pharmacol Ther ; 88(6): 792-5, 2010 Dec.
Article En | MEDLINE | ID: mdl-20739920

Sixty-two codeine-prescribed breastfeeding mothers from a pharmacogenetic study were interviewed regarding the communication of individual CYP2D6 genotype results and overall research findings. All participants wanted to receive the results of their individual genetic tests; however, individuals placed different values on the usefulness of this information toward future medical decisions. Receiving one's pharmacogenetic test results was not associated with a negative psychosocial impact. Thirty-three percent of the participants wished to withhold these results from their physicians. Participants' expectations seem to dictate the extent of transparency of pharmacogenetic research results.


Breast Feeding , Codeine/adverse effects , Communication , Perception , Pharmacogenetics/methods , Professional-Patient Relations , Adult , Breast Feeding/adverse effects , Breast Feeding/psychology , Codeine/metabolism , Cohort Studies , Cytochrome P-450 CYP2D6/genetics , Female , Genetic Testing/methods , Genetic Testing/psychology , Humans , Infant, Newborn , Patient Preference/psychology , Pharmacogenetics/trends , Pilot Projects , Surveys and Questionnaires
14.
Public Health Genomics ; 12(3): 191-201, 2009.
Article En | MEDLINE | ID: mdl-19204423

BACKGROUND: This paper presents the results of an exploratory qualitative study that assesses Canadian pediatric researchers' perceptions of a pre-selected group of ethical issues raised by pharmacogenomics research with children. METHODS: As a pilot study, we conducted semi-structured telephone interviews with Canadian pediatric pharmacogenomic researchers. The interviews were guided by the following themes: (1) benefits and risks of inclusion, (2) the consent/assent process, and (3) the return of research results. RESULTS: Issues about assent, consent, risks and benefits, as well as the communication of results were addressed by the respondents. Some issues, such as the unique vulnerability of children, the long term privacy concerns associated with biobanking, additional core elements that need to be discussed and included in the consent/assent forms, as well as the challenges of communicating research results in a pediatric research were not explicitly identified by the respondents. CONCLUSION: Further consideration should be given to address the ethical challenges of including children in pharmacogenomics research. This exploratory study indicates that further guidance is needed if children are to be protected and yet benefit from such research.


Ethics, Research , Pharmacogenetics/ethics , Research Personnel/ethics , Research Personnel/psychology , Child , Humans , Interviews as Topic , Pilot Projects
15.
J Phys Condens Matter ; 21(26): 265402, 2009 Jul 01.
Article En | MEDLINE | ID: mdl-21828471

'Forbidden' Bragg reflections of iron orthoborate Fe(3)BO(6) were studied theoretically and experimentally in the vicinity of the iron K edge. Their energy spectra are explained as resulting from the interference of x-rays scattered from two inequivalent crystallographic sites occupied by iron ions. This particular structure property gives rise to complex azimuthal dependences of the reflection intensities in the pre-edge region as they result from the interplay of site specific dipole-quadrupole and quadrupole-quadrupole resonant scattering. Also evidenced is an anisotropic character of the absorption spectrum. Self-absorption correction to the diffraction data, as well as possible contributions of thermal vibrations and magnetic order, are discussed. Particular care is given to extracting clean spectra from the data, and it is demonstrated that excellent results can be obtained even from measurements that appear corrupted by several effects such as poor crystal quality and multiple scattering.

16.
J Phys Condens Matter ; 21(48): 485601, 2009 Dec 02.
Article En | MEDLINE | ID: mdl-21832526

Despite being one of the oldest known magnetic materials, and the classic mixed valence compound, thought to be charge ordered, the structure of magnetite below the Verwey transition is complex and the presence and role of charge order is still being debated. Here, we present resonant x-ray diffraction data at the iron K-edge on forbidden (0, 0, 2n+1)(C) and superlattice [Formula: see text] reflections. Full linear polarization analysis of the incident and scattered light was conducted in order to explore the origins of the reflections. Through simulation of the resonant spectra we have confirmed that a degree of charge ordering takes place, while the anisotropic tensor of susceptibility scattering is responsible for the superlattice reflections below the Verwey transition. We also report the surprising result of the conversion of a significant proportion of the scattered light from linear to nonlinear polarization.

17.
J Phys Condens Matter ; 21(34): 345501, 2009 Aug 26.
Article En | MEDLINE | ID: mdl-21715786

We implemented a self-consistent, real-space x-ray absorption calculation within the FDMNES code. We performed the self-consistency within several schemes and identified which one is the most appropriate. We show a method that allows a rigorous setting of the Fermi level and thus an estimation of the energy cutoff for the identification and elimination of the occupied states. We investigated what are the structures where one can afford performing the self-consistent calculation at a lesser cluster radius than the absorption one. We exemplify the effects of the self-consistency at the K-edge and for several reference cases, including the copper Cu and the rutile TiO(2). We verified the robustness of our procedure on the transitional 3d and 4d elements. Although amelioration can be noticed, the self-consistency performed at the K-edge does not bring a major improvement of the calculated spectra. Taking into consideration a non-self-consistent, non-spherical potential gives better results than a self-consistent muffin-tin approximation calculation.

18.
Phys Rev Lett ; 101(22): 226401, 2008 Nov 28.
Article En | MEDLINE | ID: mdl-19113492

The subtle interplay among electronic degrees of freedom (charge and orbital orderings), spin and lattice distortion that conspire at the Verwey transition in magnetite (Fe3O4) is still a matter of controversy. Here, we provide compelling evidence that these electronic orderings are manifested as a continuous phase transition at the temperature where a spin reorientation takes place at around 130 K, i.e., well above TV approximately 121 K. The Verwey transition seems to leave the orbital ordering unaffected whereas the charge ordering development appears to be quenched at this temperature and the temperature dependence below TV is controlled by the lattice distortions. Finally, we show that the orbital ordering does not reach true long range (disorder), and the correlation length along the c-direction is limited to 100 angstroms.


Ferrosoferric Oxide/chemistry , Chemical Phenomena , X-Ray Diffraction
19.
Phys Rev Lett ; 97(5): 056403, 2006 Aug 04.
Article En | MEDLINE | ID: mdl-17026123

Here we show that the low temperature phase of magnetite is associated with an effective, although fractional, ordering of the charge. Evidence and a quantitative evaluation of the atomic charges are achieved by using resonant x-ray diffraction (RXD) experiments whose results are further analyzed with the help of ab initio calculations of the scattering factors involved. By confirming the results obtained from x-ray crystallography we have shown that RXD is able to probe quantitatively the electronic structure in very complex oxides, whose importance covers a wide domain of applications.

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