284 research outputs found
Pairing phase transition: A Finite-Temperature Relativistic Hartree-Fock-Bogoliubov study
Background: The relativistic Hartree-Fock-Bogoliubov (RHFB) theory has
recently been developed and it provides a unified and highly predictive
description of both nuclear mean field and pairing correlations. Ground state
properties of finite nuclei can accurately be reproduced without neglecting
exchange (Fock) contributions. Purpose: Finite-temperature RHFB (FT-RHFB)
theory has not yet been developed, leaving yet unknown its predictions for
phase transitions and thermal excitations in both stable and weakly bound
nuclei. Method: FT-RHFB equations are solved in a Dirac Woods-Saxon (DWS) basis
considering two kinds of pairing interactions: finite or zero range. Such a
model is appropriate for describing stable as well as loosely bound nuclei
since the basis states have correct asymptotic behaviour for large spatial
distributions. Results: Systematic FT-RH(F)B calculations are performed for
several semi-magic isotopic/isotonic chains comparing the predictions of a
large number of Lagrangians, among which are PKA1, PKO1 and DD-ME2. It is found
that the critical temperature for a pairing transition generally follows the
rule for a finite-range pairing force and for a contact pairing force, where is the pairing
gap at zero temperature. Two types of pairing persistence are analysed: type I
pairing persistence occurs in closed subshell nuclei while type II pairing
persistence can occur in loosely bound nuclei strongly coupled to the continuum
states. Conclusions: This first FT-RHFB calculation shows very interesting
features of the pairing correlations at finite temperature and in finite
systems such as pairing re-entrance and pairing persistence.Comment: 13 pages, 11 figures, accepted version in Phys. Rev.
Magicity of neutron-rich isotopes within relativistic self-consistent approaches
The formation of new shell gaps in intermediate mass neutron-rich nuclei is
investigated within the relativistic Hartree-Fock-Bogoliubov theory, and the
role of the Lorentz pseudo-vector and tensor interactions is analyzed. Based on
the Foldy-Wouthuysen transformation, we discuss in detail the role played by
the different terms of the Lorentz pseudo-vector and tensor interactions in the
appearing of the , 32 and 34 shell gaps. The nuclei O, Si
and Ca are predicted with a large shell gap and zero (O,
Ca) or almost zero (Si, Ca) pairing gap, making them
candidates for new magic numbers in exotic nuclei. We find from our analysis
that the Lorentz pseudo-vector and tensor interactions induce very specific
evolutions of single-particle energies, which could clearly sign their presence
and reveal the need for relativistic approaches with exchange interactions.Comment: 7 pages, 5 figures, 1 tabl
Enhanced and reduced atom number fluctuations in a BEC splitter
We measure atom number statistics after splitting a gas of ultracold 87Rb
atoms in a purely magnetic double-well potential created on an atom chip. Well
below the critical temperature for Bose-Einstein condensation T_c, we observe
reduced fluctuations down to -4.9dB below the atom shot noise level.
Fluctuations rise to more than +3.8dB close to T_c, before reaching the shot
noise level for higher temperatures. We use two-mode and classical field
simulations to model these results. This allows us to confirm that the
super-shot noise fluctuations directly originate from quantum statistics
Cavity-based single atom preparation and high-fidelity hyperfine state readout
We prepare and detect the hyperfine state of a single 87Rb atom coupled to a
fiber-based high finesse cavity on an atom chip. The atom is extracted from a
Bose-Einstein condensate and trapped at the maximum of the cavity field,
resulting in a reproducibly strong atom-cavity coupling. We use the cavity
reflection and transmission signal to infer the atomic hyperfine state with a
fidelity exceeding 99.92% in a read-out time of 100 microseconds. The atom is
still trapped after detection.Comment: 5 pages, 4 figure
Grass MicroRNA Gene Paleohistory Unveils New Insights into Gene Dosage Balance in Subgenome Partitioning after Whole-Genome Duplication
Dense matter with eXTP
In this White Paper we present the potential of the Enhanced X-ray Timing and
Polarimetry (eXTP) mission for determining the nature of dense matter; neutron
star cores host an extreme density regime which cannot be replicated in a
terrestrial laboratory. The tightest statistical constraints on the dense
matter equation of state will come from pulse profile modelling of
accretion-powered pulsars, burst oscillation sources, and rotation-powered
pulsars. Additional constraints will derive from spin measurements, burst
spectra, and properties of the accretion flows in the vicinity of the neutron
star. Under development by an international Consortium led by the Institute of
High Energy Physics of the Chinese Academy of Science, the eXTP mission is
expected to be launched in the mid 2020s.Comment: Accepted for publication on Sci. China Phys. Mech. Astron. (2019
High Burden of Non-Influenza Viruses in Influenza-Like Illness in the Early Weeks of H1N1v Epidemic in France
BACKGROUND: Influenza-like illness (ILI) may be caused by a variety of pathogens. Clinical observations are of little help to recognise myxovirus infection and implement appropriate prevention measures. The limited use of molecular tools underestimates the role of other common pathogens. OBJECTIVES: During the early weeks of the 2009-2010 flu pandemic, a clinical and virological survey was conducted in adult and paediatric patients with ILI referred to two French University hospitals in Paris and Tours. Aims were to investigate the different pathogens involved in ILI and describe the associated symptoms. METHODS: H1N1v pandemic influenza diagnosis was performed with real time RT-PCR assay. Other viral aetiologies were investigated by the molecular multiplex assay RespiFinder19®. Clinical data were collected prospectively by physicians using a standard questionnaire. RESULTS: From week 35 to 44, endonasal swabs were collected in 413 patients. Overall, 68 samples (16.5%) were positive for H1N1v. In 13 of them, other respiratory pathogens were also detected. Among H1N1v negative samples, 213 (61.9%) were positive for various respiratory agents, 190 in single infections and 23 in mixed infections. The most prevalent viruses in H1N1v negative single infections were rhinovirus (62.6%), followed by parainfluenza viruses (24.2%) and adenovirus (5.3%). 70.6% of H1N1v cases were identified in patients under 40 years and none after 65 years. There was no difference between clinical symptoms observed in patients infected with H1N1v or with other pathogens. CONCLUSION: Our results highlight the high frequency of non-influenza viruses involved in ILI during the pre-epidemic period of a flu alert and the lack of specific clinical signs associated with influenza infections. Rapid diagnostic screening of a large panel of respiratory pathogens may be critical to define and survey the epidemic situation and to provide critical information for patient management
An international Delphi consensus statement on metabolic dysfunction-associated fatty liver disease and risk of chronic kidney disease
Background: With the rising global prevalence of fatty liver disease related to metabolic dysfunction, the association of this common liver condition with chronic kidney disease (CKD) has become increasingly evident. In 2020, the more inclusive term metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed to replace the term non-alcoholic fatty liver disease (NAFLD). The observed association between MAFLD and CKD and our understanding that CKD can be a consequence of underlying metabolic dysfunction support the notion that individuals with MAFLD are at higher risk of having and developing CKD compared with those without MAFLD. However, to date, there is no appropriate guidance on CKD in individuals with MAFLD. Furthermore, there has been little attention paid to the link between MAFLD and CKD in the Nephrology community. Methods and Results: Using a Delphi-based approach, a multidisciplinary panel of 50 international experts from 26 countries reached a consensus on some of the open research questions regarding the link between MAFLD and CKD. Conclusions: This Delphi-based consensus statement provided guidance on the epidemiology, mechanisms, management and treatment of MAFLD and CKD, as well as the relationship between the severity of MAFLD and risk of CKD, which establish a framework for the early prevention and management of these two common and interconnected diseases.Fil: Sun, Dan Qin. Jiangnan University Medical Center; China. Nantong University; ChinaFil: Targher, Giovanni. Azienda Ospedaliera Universitaria Integrata Verona; ItaliaFil: Byrne, Christopher D.. University of Southampton; Reino UnidoFil: Wheeler, David C.. University College London; Estados UnidosFil: Wong, Vincent Wai Sun. Chinese University of Hong Kong; ChinaFil: Fan, Jian Gao. Shanghai Jiao Tong University; ChinaFil: Tilg, Herbert. Medical University Innsbruck; AustriaFil: Yuan, Wei Jie. Shanghai Jiao Tong University; ChinaFil: Wanner, Christoph. Würzburg University Clinic; AlemaniaFil: Gao, Xin. Fudan University; ChinaFil: Long, Michelle T.. Boston University School of Medicine; Estados UnidosFil: Kanbay, Mehmet. Koc University School of Medicine; TurquíaFil: Nguyen, Mindie H.. Stanford University Medical Center; Estados UnidosFil: Navaneethan, Sankar D.. Baylor College of Medicine; Estados UnidosFil: Yilmaz, Yusuf. Marmara University; Turquía. Recep Tayyip Erdoğan University; TurquíaFil: Huang, Yuli. Southern Medical University; ChinaFil: Gani, Rino A.. Universitas Indonesia; IndonesiaFil: Marzuillo, Pierluigi. Università della Campania “Luigi Vanvitelli”; ItaliaFil: Boursier, Jérôme. Angers University; FranciaFil: Zhang, Huijie. Southern Medical University; ChinaFil: Jung, Chan Young. Yonsei University; Corea del SurFil: Chai, Jin. Army Medical University; ChinaFil: Valenti, Luca. Università degli Studi di Milano; ItaliaFil: Papatheodoridis, George. Kapodistrian University of Athens; GreciaFil: Sookoian, Silvia Cristina. Centro de Investigacion Traslacional En Salud (cenitres) ; Facultad de Cs. de la Salud ; Universidad Maimonides; . Universidad Abierta Interamericana; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Chunsun, Dai. Nanjing Medical University; ChinaFil: Eslam, Mohammed. University of Sydney; AustraliaFil: Wei, Lai. Tsinghua University; ChinaFil: George, Jacob. University of Sydney; AustraliaFil: Zheng, Ming Hua. Wenzhou Medical University; Chin
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