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1.
Clin Transl Radiat Oncol ; 46: 100762, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38572302

RESUMO

Oligometastases are defined as a number of detectable metastases less or equal to 5. In castrate-resistant oligo metastatic prostate Cancer (CR oligoM PC), Metastases-Directed Ablative radiotherapy (MDRT) is poorly investigated. Our study retrospectively reviewed the cases of CR oligoM PC treated with MDRT in 8 French high-volume radiotherapy centers. OS and PFS are defined as the delay between the first day of MDRT and death (OS) or progression according to PCWG criteria (PFS). OS and PFS are evaluated according to Kaplan Meyer, curves are compared with log rank test. Logistic regression was used to identify predictive factors for outcome: bone versus node metastasis, ISUP grade, PSA doubling Time (PSADT) at the time of MDRT, time to castration resistance. 107 patients were included in the study, among those 197 metastases received MDRT. For the overall population, the median follow-up was 25.2 months (1,4-145). OS was 93 % at 2 years and 81,4% at 3 years. At 2 years, 100 % of patients with node-only metastasis were alive versus 88,7% among those who have bone metastases (p = 0,72). The median PFS was 12,6 months (IC 95 % [9,6; 17]), with no difference among patients with node only disease versus the rest of the cohort. The PFS was 18,2 months (10,0; 32,4) in patients with PSADT >6 months versus 10,7 months (8,9; 14,3) when PSADT was inferior to 6 months. However, this difference did not reach significant. We did not find a correlation neither between ISUP grade (1-2 versus 3-4-5) and PFS, nor between hormone-sensitivity duration and PFS. Patients receiving MDRT for CR oligoM PC have a good prognosis with 81,6% OS at 3 years. PSA DT longer than 6 months could be related to better PFS. MDRT strategy could postpone the onset of new systemic treatment with median PFS >1 year.

2.
Health Promot Pract ; 24(3): 395-397, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36648059

RESUMO

Mental health professionals aim to engage our clients with "accurate empathy": a nonjudgmental understanding of each person's starting point and experiences that is in tune with their perspective. This article explores the challenges and importance of developing this type of engagement in complex contexts, using the lens of group work with a disparate set of LGBTQIA2S+ young adults whose identities, backgrounds, and experiences differed from one another and from the facilitator. The author reflects on experiences from a grant-based position creating and running a trauma-informed support group in an emergency shelter for unhoused LGBTQIA2S+ young adults in a major U.S. city, including the impact of common issues in the field such as staff turnover, confusion about roles and needs, and support. The article describes lessons learned about the importance of language choice, self-reflection, and the need to confront and build on differences to create a shared process of support.


Assuntos
Pessoas Mal Alojadas , Minorias Sexuais e de Gênero , Adolescente , Humanos , Adulto Jovem
3.
Nano Lett ; 22(12): 5022-5028, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35679580

RESUMO

Spin electronics is delivering a much desired combination of properties such as high speed, low power, and high device densities for the next generation of memory devices. Utilizing chiral-induced spin selectivity (CISS) effect is a promising path toward efficient and simple spintronic devices. To be compatible with state-of-the-art integrated circuits manufacturing methodologies, vapor phase methodologies for deposition of spin filtering layers are needed. Here, we present vapor phase deposition of hybrid organic-inorganic thin films with embedded chirality. The deposition scheme relies on a combination of atomic and molecular layer deposition (A/MLD) utilizing enantiomeric pure alaninol molecular precursors combined with trimethyl aluminum (TMA) and water. The A/MLD deposition method deliver highly conformal thin films allowing the fabrication of several types of nanometric scale spintronic devices. The devices showed high spin polarization (close to 100%) for 5 nm thick spin filter layer deposited by A/MLD. The procedure is compatible with common device processing methodologies.

4.
Arch Sex Behav ; 51(4): 2135-2145, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35604513

RESUMO

Research on asexuality as a part of the experience of human sexuality has increased over the last two decades. However, there has not yet been a systematic review of the extant literature on asexuality. This paper aims to provide a systematic scoping review of literature on asexuality with articles published in 2004 through August 2021. After a systematic search procedure, 48 studies were included. A codebook was developed to extract broad information about the literature on asexuality, including sampling techniques, research participant sociodemographics, and conceptualization of asexuality. Results of the review indicate that the research is currently split between qualitative and quantitative methods. The literature primarily relied on convenience sampling within asexual online communities. The primary online community was Asexual Visibility and Education Network (AVEN), which may have contributed to the majority of participants being White, presumptively cisgender, women between the ages of 20-30. Analysis of the overall literature scope demonstrates no support for asexuality as a medical condition (i.e., a disorder requiring treatment) and instead supports the need to recognize asexuality as a complex identity and sexual orientation. Implications for research are discussed, such as the need for additional research on the topic of human sexuality that includes asexuality as a sexual orientation as well as the need for more intersectional research within the literature.


Assuntos
Comportamento Sexual , Sexualidade , Adulto , Pesquisa Empírica , Feminino , Humanos , Masculino , Rede Social , Ciências Sociais , Adulto Jovem
5.
Phys Rev Lett ; 128(11): 113001, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35363015

RESUMO

The recently developed exact factorization approach condenses all electronic effects on the nuclear subsystem into scalar and vector potentials that appear in an effective time dependent Schrödinger equation. Starting from this equation, we derive subsystem Ehrenfest identities characterizing the energy, momentum, and angular momentum transfer between electrons and nuclei. An effective electromagnetic force operator induced by the electromagnetic field corresponding to the effective scalar and vector potentials appears in all three identities. The effective magnetic field has two components that can be identified with the Berry curvature calculated with (a) different Cartesian coordinates of the same nucleus and (b) arbitrary Cartesian coordinates of two different nuclei. (a) has a classical interpretation as the induced magnetic field felt by the nucleus, while (b) has no classical analog. Subsystem Ehrenfest identities are ideally suited for quantifying energy transfer in electron-phonon systems. With two explicit examples we demonstrate the usefulness of the new identities.

6.
J Phys Condens Matter ; 34(18)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-34544070

RESUMO

Designing materials with advanced functionalities is the main focus of contemporary solid-state physics and chemistry. Research efforts worldwide are funneled into a few high-end goals, one of the oldest, and most fascinating of which is the search for an ambient temperature superconductor (A-SC). The reason is clear: superconductivity at ambient conditions implies being able to handle, measure and access a single, coherent, macroscopic quantum mechanical state without the limitations associated with cryogenics and pressurization. This would not only open exciting avenues for fundamental research, but also pave the road for a wide range of technological applications, affecting strategic areas such as energy conservation and climate change. In this roadmap we have collected contributions from many of the main actors working on superconductivity, and asked them to share their personal viewpoint on the field. The hope is that this article will serve not only as an instantaneous picture of the status of research, but also as a true roadmap defining the main long-term theoretical and experimental challenges that lie ahead. Interestingly, although the current research in superconductor design is dominated by conventional (phonon-mediated) superconductors, there seems to be a widespread consensus that achieving A-SC may require different pairing mechanisms.In memoriam, to Neil Ashcroft, who inspired us all.

7.
Phys Rev Lett ; 127(11): 116401, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34558918

RESUMO

A many-body wave function can be factorized in Fock space into a marginal amplitude describing a set of strongly correlated orbitals and a conditional amplitude for the remaining weakly correlated part. The marginal amplitude is the solution of a Schrödinger equation with an effective Hamiltonian that can be viewed as embedding the marginal wave function in the environment of weakly correlated electrons. Here, the complementary equation for the conditional amplitude is replaced by a generalized Kohn-Sham equation, for which an orbital-dependent functional approximation is shown to reproduce the topological phase diagram of a multiband Hubbard model as a function of crystal field and Hubbard parameters. The roles of band filling and interband fluctuations are elucidated.

8.
J Appl Microbiol ; 131(6): 2748-2762, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33971065

RESUMO

AIMS: We tested the hypothesis that the behaviour of an individual is associated with the diversity of its gut bacteria, using the collared peccary (Pecari tajacu) as a model. METHODS AND RESULTS: In all, 24 adult male collared peccaries received either low- (n = 12) or high-fibre diet (n = 12) to induce contrasting gut fermentation profiles. They were submitted to three short-term challenges, allowing us to rate the animals in a coping-style dimension named 'calmness'. At the end of the experimental period, we collected samples of peccaries' forestomach contents to characterize bacterial diversity. We found a significant positive association between individual 'calmness' z-scores and the bacterial evenness index in gut bacteria (and a similar trend with the Simpson's diversity index), suggesting a more homogeneous bacterial community of calmer individuals. We also found a positive association between fibres digestibility and gut bacterial diversity in the peccaries' forestomach, but no effect of the dietary fibre level. CONCLUSIONS: Gut bacteria evenness increases with 'calmness' z-scores, suggesting a more homogeneous bacterial community of calmer individuals, compared with the more heterogeneous of the most distressed ones. Our results also suggest associations between the digestibility of ADF with the gut bacterial diversity indices and with the relative abundance of the Actinobacteria phylum. SIGNIFICANCE AND IMPACT OF THE STUDY: Our data showed that the hosts' individual behavioural differences are potentially aligned with gut bacterial diversity. The behaviour-microbiota link is correlated with host feed efficiency and, ultimately, may have implications for animal health and welfare of farm animals.


Assuntos
Artiodáctilos , Individualidade , Animais , Bactérias/genética , Fibras na Dieta , Humanos , Masculino
9.
J Chem Theory Comput ; 17(3): 1390-1407, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33595312

RESUMO

Accurately describing excited states within Kohn-Sham (KS) density functional theory (DFT), particularly those which induce ionization and charge transfer, remains a great challenge. Common exchange-correlation (xc) approximations are unreliable for excited states owing, in part, to the absence of a derivative discontinuity in the xc energy (Δ), which relates a many-electron energy difference to the corresponding KS energy difference. We demonstrate, analytically and numerically, how the relationship between KS and many-electron energies leads to the step structures observed in the exact xc potential in four scenarios: electron addition, molecular dissociation, excitation of a finite system, and charge transfer. We further show that steps in the potential can be obtained also with common xc approximations, as simple as the LDA, when addressed from the ensemble perspective. The article therefore highlights how capturing the relationship between KS and many-electron energies with advanced xc approximations is crucial for accurately calculating excitations, as well as the ground-state density and energy of systems which consist of distinct subsystems.

10.
Cancer Radiother ; 24(8): 892-897, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33144063

RESUMO

PURPOSE: The intermediate-risk (IR) prostate cancer (PCa) group is heterogeneous in terms of prognosis. For unfavorable or favorable IR PCa treated by radiotherapy, the optimal strategy remains to be defined. In routine practice, the physician's decision to propose hormonal therapy (HT) is controversial. The PROACT survey aimed to evaluate pattern and preferences of daily practice in France in this IR population. MATERIALS AND METHODS: A web questionnaire was distributed to French radiotherapy members of 91 centers of the Groupe d'Etude des Tumeurs Uro-Genitales (GETUG). The questionnaire included four sections concerning: (i) the specialists who prescribe treatments and multidisciplinary decisions (MTD) validation; (ii) the definition of IR subsets of patients; (iii) radiotherapy parameters; (iv) the pattern of practice regarding cardiovascular (CV) and (iv) metabolic evaluation. A descriptive presentation of the results was used. RESULTS: Among the 82 responses (90% of the centers), HT schedules and irradiation techniques were validated by specific board meetings in 54% and 45% of the centers, respectively. Three-fourths (76%) of the centers identified a subset of IR patients for a dedicated strategy. The majority of centers consider PSA>15 (77%) and/or Gleason 7 (4+3) (87%) for an unfavorable IR definition. Overall, 41% of the centers performed systematically a CV evaluation before HT prescription while 61% consider only CV history/status in defining the type of HT. LHRH agonists are more frequently prescribed in both favorable (70%) and unfavorable (98%) IR patients. Finally, weight (80%), metabolic profile (70%) and CV status (77%) of patients are considered for follow-up under HT. CONCLUSION: To the best of our knowledge, this is the first survey on HT practice in IR PCa. The PROACT survey indicates that three-quarters of the respondents identify subsets of IR-patients in tailoring therapy. The CV status of the patient is considered in guiding the HT decision, its duration and type of drug.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Pesquisas sobre Atenção à Saúde/estatística & dados numéricos , Neoplasias da Próstata/terapia , Institutos de Câncer/estatística & dados numéricos , França , Humanos , Masculino , Padrões de Prática Médica/estatística & dados numéricos , Prognóstico , Neoplasias da Próstata/patologia , Radio-Oncologistas/estatística & dados numéricos
11.
Phys Rev Lett ; 125(5): 057001, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32794891

RESUMO

We propose a practical alternative to Eliashberg equations for the ab initio calculation of superconducting transition temperatures and gap functions. Within the recent density functional theory for superconductors, we develop an exchange-correlation functional that retains the accuracy of Migdal's approximation to the many-body electron-phonon self-energy, while having a simple analytic form. Our functional is based on a parametrization of the Eliashberg self-energy for a superconductor with a single Einstein frequency, and enables density functional calculations of experimental excitation gaps. By merging electronic structure methods and Eliashberg theory, the present approach sets a new standard in quality and computational feasibility for the prediction of superconducting properties.

12.
Phys Rev Lett ; 125(25): 256402, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33416390

RESUMO

We present a method that enables solid-state density functional theory calculations to be applied to systems of almost unlimited size. Computations of physical effects up to the micron length scale but which nevertheless depend on the microscopic details of the electronic structure, are made possible. Our approach is based on a generalization of the Bloch state, which involves an additional sum over a finer grid in reciprocal space around each k point. We show that this allows for modulations in the density and magnetization of arbitrary length on top of a lattice-periodic solution. Based on this, we derive a set of ultra-long-range Kohn-Sham equations. We demonstrate our method with a sample calculation of bulk LiF subjected to an arbitrary external potential containing nearly 3500 atoms. We also confirm the accuracy of the method by comparing the spin density wave state of bcc Cr against a direct supercell calculation starting from a random magnetization density. Furthermore, the spin spiral state of γ-Fe is correctly reproduced.

13.
J Phys Condens Matter ; 31(33): 334001, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31071706

RESUMO

Within recent developments of density functional theory, its numerical implementation and of the superconducting density functional theory is nowadays possible to predict the superconducting critical temperature, [Formula: see text], with sufficient accuracy to anticipate the experimental verification. In this paper we present an analytical derivation of the isotope coefficient within the superconducting density functional theory. We calculate the partial derivative of [Formula: see text] with respect to atomic masses. We verified the final expression by means of numerical calculations of isotope coefficient in monatomic superconductors (Pb) as well as polyatomic superconductors (CaC6). The results confirm the validity of the analytical derivation with respect to the finite difference methods, with considerable improvement in terms of computational time and calculation accuracy. Once the critical temperature is calculated (at the reference mass(es)), various isotope exponents can be simply obtained in the same run. In addition, we provide the expression of interesting quantities like partial derivatives of the deformation potential, phonon frequencies and eigenvectors with respect to atomic masses, which can be useful for other derivations and applications.

14.
Phys Rev Lett ; 122(6): 067202, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30822073

RESUMO

By combining interface-sensitive nonlinear magneto-optical experiments with femtosecond time resolution and ab initio time-dependent density functional theory, we show that optically excited spin dynamics at Co/Cu(001) interfaces proceeds via spin-dependent charge transfer and back transfer between Co and Cu. This ultrafast spin transfer competes with dissipation of spin angular momentum mediated by spin-orbit coupling already on sub 100 fs timescales. We thereby identify the fundamental microscopic processes during laser-induced spin transfer at a model interface for technologically relevant ferromagnetic heterostructures.

15.
J Phys Chem Lett ; 9(24): 7045-7051, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30501191

RESUMO

The many-body Berry phase formula for macroscopic polarization is approximated by a sum of natural orbital geometric phases with fractional occupation numbers accounting for the dominant correlation effects. This formula accurately reproduces the exact polarization in the Rice-Mele-Hubbard model across the band insulator-Mott insulator transition. A similar formula based on a reduced Berry curvature accurately predicts the interaction-induced quenching of Thouless topological charge pumping.

16.
Data Brief ; 20: 2054-2064, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30310830

RESUMO

Here we report the IR spectra of FeEnterobactin in catecholate conformations ([CatFeEB]3-) obtained by DFT calculations using PBE/QZVP and their correlation it with its experimental counterpart [SalH3FeEB]0. Fragments of FeEnterobactin and Enterobactin (H6EB) are elucidated from their MALDI-TOF mass spectrometry, and the dependence of the frontier orbitals (HOMO and LUMO) with the catecholamide dihedral angles of H6EB is reported. The frequency distribution of catecholamide dihedral angle of H6EB was carried-out using molecular dynamics (MD). The data presented enriches the understanding of [CatFeEB]3 - and H6EB frequency distribution and reactivity.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 198: 264-277, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29550657

RESUMO

Emerging and re-emerging epidemic diseases pose an ongoing threat to global health. Currently, Enterobactin and Enterobactin derivatives have gained interest, owing to their potential application in the pharmaceutical field. As it is known [J. Am. Chem. Soc (1979) 101, 20, 6097-6104], Enterobactin (H6EB) is an efficient iron carrier synthesized and secreted by many microbial species. In order to facilitate the elucidation of enterobactin and its analogues, here we propose the creation of a H6EB standard set using Density Functional Theory Infrared (IR) and NMR spectra. We used two exchange-correlation (xc) functionals (PBE including long-range corrections LC-PBE and mPW1), 2 basis sets (QZVP and 6-31G(d)) and 2 grids (fine and ultrafine) for most of the H6EB structures dependent of dihedral angles. The results show a significant difference between the OH and NH bands, while the CO amide and O(CO) IR bands are often found on top of each other. The NMR DFT calculations show a strong dependence on the xc functional, basis set, and grid used for the H6EB structure. Calculated 1H and 13C NMR spectra enable the effect of the solvent to be understood in the context of the experimental measurements. The good agreement between the experimental and the calculated spectra using LC-PBE/QZVP and ultrafine grid suggest the possibility of the systems reported here to be considered as a standard set. The dependence of electrostatic potential and frontier orbitals with the catecholamide dihedral angles of H6EB is described. The matrix-assisted laser desorption/ionization time of the flight mass spectrometry (MALDI-TOF MS) of H6EB is also reported of manner to enrich the knowledge about its reactivity.


Assuntos
Enterobactina/química , Espectroscopia de Ressonância Magnética , Espectrofotometria Infravermelho , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
18.
J Chem Phys ; 148(8): 084110, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29495788

RESUMO

We perform model calculations for a stretched LiF molecule, demonstrating that nonadiabatic charge transfer effects can be accurately and seamlessly described within a density functional framework. In alkali halides like LiF, there is an abrupt change in the ground state electronic distribution due to an electron transfer at a critical bond length R = Rc, where an avoided crossing of the lowest adiabatic potential energy surfaces calls the validity of the Born-Oppenheimer approximation into doubt. Modeling the R-dependent electronic structure of LiF within a two-site Hubbard model, we find that nonadiabatic electron-nuclear coupling produces a sizable elongation of the critical Rc by 0.5 bohr. This effect is very accurately captured by a simple and rigorously derived correction, with an M-1 prefactor, to the exchange-correlation potential in density functional theory, M = reduced nuclear mass. Since this nonadiabatic term depends on gradients of the nuclear wave function and conditional electronic density, ∇Rχ(R) and ∇Rn(r, R), it couples the Kohn-Sham equations at neighboring R points. Motivated by an observed localization of nonadiabatic effects in nuclear configuration space, we propose a local conditional density approximation-an approximation that reduces the search for nonadiabatic density functionals to the search for a single function y(n).

19.
J Chem Theory Comput ; 14(3): 1247-1253, 2018 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-29420031

RESUMO

Spin-dependent exchange-correlation energy functionals in use today depend on the charge density and the magnetization density: Exc[ρ, m]. However, it is also correct to define the functional in terms of the curl of m for physical external fields: Exc[ρ,∇ × m]. The exchange-correlation magnetic field, Bxc, then becomes source-free. We study this variation of the theory by uniquely removing the source term from local and generalized gradient approximations to the functional. By doing so, the total Kohn-Sham moments are improved for a wide range of materials for both functionals. Significantly, the moments for the pnictides are now in good agreement with experiment. This source-free method is simple to implement in all existing density functional theory codes.

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