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1.
Phys Rev Lett ; 127(19): 192501, 2021 Nov 05.
Article in English | MEDLINE | ID: mdl-34797155

ABSTRACT

The changes in the mean-square charge radius (relative to ^{209}Bi), magnetic dipole, and electric quadrupole moments of ^{187,188,189,191}Bi were measured using the in-source resonance-ionization spectroscopy technique at ISOLDE (CERN). A large staggering in radii was found in ^{187,188,189}Bi^{g}, manifested by a sharp radius increase for the ground state of ^{188}Bi relative to the neighboring ^{187,189}Bi^{g}. A large isomer shift was also observed for ^{188}Bi^{m}. Both effects happen at the same neutron number, N=105, where the shape staggering and a similar isomer shift were observed in the mercury isotopes. Experimental results are reproduced by mean-field calculations where the ground or isomeric states were identified by the blocked quasiparticle configuration compatible with the observed spin, parity, and magnetic moment.

2.
J Chem Phys ; 154(22): 224303, 2021 Jun 14.
Article in English | MEDLINE | ID: mdl-34241194

ABSTRACT

The YbOH triatomic molecule can be efficiently used to measure the electron electric dipole moment, which violates time-reversal (T) and spatial parity (P) symmetries of fundamental interactions [Kozyryev and Hutzler, Phys. Rev. Lett. 119, 133002 (2017)]. We study another mechanism of the T, P-violation in the YbOH molecule-the electron-electron interaction mediated by the low-mass axionlike particle. For this, we calculate the molecular constant that characterizes this interaction and use it to estimate the expected magnitude of the effect to be measured. It is shown that this molecular constant has the same order of magnitude as the corresponding molecular constant corresponding to the axion-mediated electron-nucleus interaction. According to our estimation, an experiment on YbOH will allow one to set updated laboratory constraints on the CP-violating electron-axion coupling constants.

3.
J Chem Phys ; 153(22): 224302, 2020 Dec 14.
Article in English | MEDLINE | ID: mdl-33317302

ABSTRACT

The time-reversal and spatial parity violating interaction of the nuclear magnetic quadrupole moment (MQM) of the 175Lu and 176Lu nuclei with electrons in the molecular cation LuOH+ is studied. The resulting effect is expressed in terms of fundamental parameters, such as quantum chromodynamics angle θ¯, quark electric dipole moment (EDM), and chromo-EDM. For this, we have estimated the magnetic quadrupole moments of 175Lu and 176Lu nuclei and calculated the molecular constant that characterizes the interaction of the MQM with electrons in the considered molecules. Additionally, we predict the hyperfine structure constants for the ground electronic state of LuOH+. In the molecular calculations, both the correlation and relativistic effects including the Gaunt interaction have been considered. According to the calculated expressions in terms of the fundamental constants, we conclude that LuOH+ can be a promising system to measure the nuclear MQM.

4.
J Chem Phys ; 152(4): 044301, 2020 Jan 31.
Article in English | MEDLINE | ID: mdl-32007077

ABSTRACT

The influence of the nuclear magnetization distribution effects on the hyperfine structure of electronic states of thallium atom is studied within the relativistic coupled cluster theory. Relative significance of these effects is demonstrated for the first excited electronic state 6P3/2 of neutral Tl. Based on the obtained theoretical and available experimental data, the nuclear magnetic moments of short-lived 191Tlm and 193Tlm isotopes are predicted: µ191 = 3.79(2) µN and µ193 = 3.84(3) µN, respectively. Using theoretical and experimental data for the neutral Tl, the magnetic anomalies 205Δ203 for the 7S1/2 state of the neutral Tl atom and the 1S1/2 state of the hydrogen-like ion are also predicted.

5.
Med Trop (Mars) ; 70(3): 249-54, 2010 Jun.
Article in French | MEDLINE | ID: mdl-20734592

ABSTRACT

In 2006, the Regional Health Office (DSDS) in French Guiana undertook a major operation involving importation and distribution of long-lasting insecticide treated nets (LLIN/ITN). In collaboration with the WHO, a Vietnamese manufacturer of LLINs suited to the requirements of French Guiana was sourced. With the help of a dynamic local importer and dealer, a sales network was developed through chemist shops located all over French Guiana. This network provided wide coverage since these outlets can be found in all large communities. The selling price ranged from 15 to 23 euros depending on the model, i.e., hammock or bed size. In addition, LLINs were distributed within the framework of two special programs. First they are given to women giving birth in French Guiana and undergoing medical surveillance as part of the Mother and Child Protection program by public healthcare system. Second they are distributed in case of natural disaster or other events that could lead to an increased risk of vector-borne outbreaks. Thanks to this operation, a total of 13,882 LLINs were delivered in French Guiana from July 2006 to December 2008. This milestone operation in the fight against malaria was made possible thanks to funding granted on a one-time basis after the outbreak of dengue in 2005-2006. The structure of this operation and its survival will depend on the continued goodwill and determination of a small group of local partners who created this successful distribution campaign with no specific guidance or program from the national authorities.


Subject(s)
Malaria/prevention & control , Mosquito Control/methods , Dengue/prevention & control , French Guiana/epidemiology , Humans , Insecticide-Treated Bednets , Malaria/economics , Malaria/epidemiology , Mosquito Control/economics , Population Surveillance , Retrospective Studies , World Health Organization
7.
Leuk Lymphoma ; 11 Suppl 1: 185-91, 1993.
Article in English | MEDLINE | ID: mdl-7504544

ABSTRACT

Treatment with interferon-alpha (IFN-alpha) adequately controls the leukemic cell mass in the majority of newly diagnosed patients with chronic myeloid leukemia (CML). However, the degree of response ranges from no 'hematologic' response to complete suppression of the leukemic clone. The mechanism(s) by which IFN-alpha elicits these responses is unknown, but in vitro studies have indicated that IFN-alpha might function by (1) selective toxicity against the leukemic clone, (2) enhancement of 'immune' regulation, and (3) modulation of bone marrow microenvironmental regulation of hematopoiesis. Using in vitro clonogenic assays we were unable to demonstrate that IFN-alpha selectively inhibited the proliferation of CML progenitor cells. We also found no difference in the expression of LFA-3 on normal or CML CD34+ cells. However, by panning and co-culturing hematopoietic cells on monolayers of bone marrow stromal cells, grown with and without IFN-alpha, we found that IFN-alpha enhanced the adhesion of CML progenitors to stromal cells, whereas adhesion by normal progenitor cells was essentially unaffected. This enhanced adhesion by CML progenitor cells was associated with a reduction in neuraminic acid levels in the extracellular matrix overlying stromal cells. Therefore, it is possible that one of the mechanisms by which IFN-alpha exerts its regulatory effect on the leukemic clone is through enhancement of hematopoietic cell-microenvironmental cell interactions.


Subject(s)
Immunologic Factors/pharmacology , Interferon-alpha/pharmacology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Neoplastic Stem Cells/drug effects , Antigens, CD/biosynthesis , Antigens, CD34 , Bone Marrow/drug effects , Bone Marrow/pathology , CD58 Antigens , Cell Adhesion/drug effects , Cell Adhesion Molecules/biosynthesis , Cell Division/drug effects , Connective Tissue/drug effects , Extracellular Matrix/chemistry , Extracellular Matrix/drug effects , Gene Expression Regulation, Leukemic/drug effects , Glycosaminoglycans/biosynthesis , Humans , Immunologic Factors/therapeutic use , Interferon-alpha/therapeutic use , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/immunology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Membrane Glycoproteins/biosynthesis , Neoplasm Proteins/biosynthesis , Neoplastic Stem Cells/immunology , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Neuraminic Acids/metabolism , Tumor Stem Cell Assay
9.
J Cell Sci ; 27: 141-55, 1977.
Article in English | MEDLINE | ID: mdl-591572

ABSTRACT

The stability of a clonal mouse neuroblastoma x rat glioma hybrid cell line was examined. Cell volume and cellular content of DNA and protein were measured as functions of the passage number. They decreased with the number of serial subcultivations. Cellular volume was linearly related to cellular DNA and protein. Thus, measurements of cell volume can be used to monitor the loss of DNA from hybrid cells. After about 60 passages a stable population of hybrid cells arose, as judged by the constancy of cellular volume and by the decreased coefficient of variation of the cell volume distribution. A mathematical model for the kinetics of the simultaneous loss of cellular volume, DNA and protein is introduced. Several neuronal properties were investigated. The specific activity of the neurotransmitter enzyme choline acetyltransferase decreased by more than 50% during 56 passages. After 70 subcultivations, the hybrid cells were still capable of extending processes, action potentials could still be elicited electrically or by iontophoretic application of acetylcholine, and the cells still responded to prostaglandin E1 as they do at low passage number.


Subject(s)
Glioma , Hybrid Cells , Neuroblastoma , Action Potentials , Animals , Cell Count , Choline O-Acetyltransferase/metabolism , Chromosomes , DNA, Neoplasm/metabolism , Glioma/metabolism , Hybrid Cells/metabolism , Mathematics , Mice , Models, Biological , Neoplasm Proteins/metabolism , Neuroblastoma/metabolism , Prostaglandins E/pharmacology , Rats , Time Factors
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