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1.
Phys Rev Lett ; 131(20): 201802, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38039466

RESUMO

We search for energetic electron recoil signals induced by boosted dark matter (BDM) from the galactic center using the COSINE-100 array of NaI(Tl) crystal detectors at the Yangyang Underground Laboratory. The signal would be an excess of events with energies above 4 MeV over the well-understood background. Because no excess of events are observed in a 97.7 kg·yr exposure, we set limits on BDM interactions under a variety of hypotheses. Notably, we explored the dark photon parameter space, leading to competitive limits compared to direct dark photon search experiments, particularly for dark photon masses below 4 MeV and considering the invisible decay mode. Furthermore, by comparing our results with a previous BDM search conducted by the Super-Kamionkande experiment, we found that the COSINE-100 detector has advantages in searching for low-mass dark matter. This analysis demonstrates the potential of the COSINE-100 detector to search for MeV electron recoil signals produced by the dark sector particle interactions.

2.
Phys Rev Lett ; 123(3): 031302, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31386435

RESUMO

We present new constraints on the dark matter-induced annual modulation signal using 1.7 years of COSINE-100 data with a total exposure of 97.7 kg yr. The COSINE-100 experiment, consisting of 106 kg of NaI(Tl) target material, is designed to carry out a model-independent test of DAMA/LIBRA's claim of WIMP discovery by searching for the same annual modulation signal using the same NaI(Tl) target. The crystal data show a 2.7 cpd/kg/keV background rate on average in the 2-6 keV energy region of interest. Using a χ-squared minimization method we observe best fit values for modulation amplitude and phase of 0.0092±0.0067 cpd/kg/keV and 127.2±45.9 d, respectively.

3.
Phys Rev Lett ; 122(13): 131802, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31012610

RESUMO

A search for inelastic boosted dark matter (IBDM) using the COSINE-100 detector with 59.5 days of data is presented. This relativistic dark matter is theorized to interact with the target material through inelastic scattering with electrons, creating a heavier state that subsequently produces standard model particles, such as an electron-positron pair. In this study, we search for this electron-positron pair in coincidence with the initially scattered electron as a signature for an IBDM interaction. No excess over the predicted background event rate is observed. Therefore, we present limits on IBDM interactions under various hypotheses, one of which allows us to explore an area of the dark photon parameter space that has not yet been covered by other experiments. This is the first experimental search for IBDM using a terrestrial detector.

4.
Linacre Q ; 80(4): 388-392, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30083016

RESUMO

When caring for of patients suffering from severe anorexia, medical teams may feel deprived in the face of the ambivalent behavior of some of these patients who accept medical care but refuse nutrition. We present here the case of a woman suffering from severe chronic anorexia with a state of morbid malnutrition, which presented the ethical question of how to deal with this unreasonable attitude. These extreme cases raise several questions regarding avoiding malfeasance and when to provide palliative care in a management of psychiatric pathology.

5.
Science ; 222(4627): 1027-9, 1983 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-17776248

RESUMO

Recognition of nestmates and discrimination against aliens is the rule in the social insects. The principal mechanism of nestmate recognition in carpenter ants (Camponotus) appears to be odor labels or "discriminators" that originate from the queen and are distributed among, and learned by, all adult colony members. The acquired odor labels are sufficiently powerful to produce indiscriminate acceptance among workers of different species raised together in artificially mixed colonies and rejection of genetic sisters reared by different heterospecific queens.

6.
Eur Phys J C Part Fields ; 78(6): 490, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30956554

RESUMO

The COSINE-100 dark matter search experiment is an array of NaI(Tl) crystal detectors located in the Yangyang Underground Laboratory (Y2L). To understand measured backgrounds in the NaI(Tl) crystals we have performed Monte Carlo simulations using the Geant4 toolkit and developed background models for each crystal that consider contributions from both internal and external sources, including cosmogenic nuclides. The background models are based on comparisons of measurement data with Monte Carlo simulations that are guided by a campaign of material assays and are used to evaluate backgrounds and identify their sources. The average background level for the six crystals (70 kg total mass) that are studied is 3.5 counts/day/keV/kg in the (2-6) keV energy interval. The dominant contributors in this energy region are found to be 210 Pb and 3 H.

7.
Proc Natl Acad Sci U S A ; 87(24): 9670-3, 1990 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11607136

RESUMO

The stage in preimaginal ontogeny at which the sexes can first be distinguished has important implications for queen-worker conflict in social insects. If workers are unable to sex larvae at an early instar, their opportunity to control colony reproductive strategies may be limited. In addition, by concealing the sex of her sons for some portion of development, the queen could protect them from the workers' attempts to substitute their own sons or to skew the numerical sex ratio. In a series of choice experiments, workers of the carpenter ant, Camponotus floridanus, failed to discriminate the sex of several stages of larvae but did retrieve female pupae significantly more rapidly than male pupae. Our results suggest that in this species, sex may not become detectable until pupation, which is consistent with sexual deception as an aspect of queen control.

8.
Science ; 235(4796): 1682b-3b, 1987 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-17795602
9.
Science ; 274(5293): 1595-6, 1996 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-8984620
10.
Science ; 274(5293): 1595c-6c, 1996 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-17842240
11.
Carbohydr Res ; 185(2): 211-23, 1989 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-2471591

RESUMO

The O-specific side-chains of the lipopolysaccharide from Escherichia coli O86:K2:H2 have been investigated using n.m.r. spectroscopy, methylation analysis, and specific degradations, and shown to be composed of the pentasaccharide repeating-unit (formula; see text) which represents the biological repeating-unit. The blood-group B activity was confirmed by an enzyme-linked immunosorbent assay.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Antígenos de Bactérias/análise , Epitopos/análise , Escherichia coli/análise , Lipopolissacarídeos/análise , Sequência de Carboidratos , Criança , Ensaio de Imunoadsorção Enzimática , Escherichia coli/imunologia , Humanos , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Metilação , Dados de Sequência Molecular
12.
Presse Med ; 32(5): 203-11, 2003 Feb 08.
Artigo em Francês | MEDLINE | ID: mdl-12610460

RESUMO

OBJECTIVE: The end-point of this survey was to evaluate the number of patients in advanced or terminal phase of a life-threatening disease and hospitalised in the university hospital in Grenoble on a given day. The secondary end-points were determination of the profile of patients undergoing palliative care and the therapeutic charge they represented for the hospital in order to develop optimal medico-psycho-social responses adapted to the needs of this population, their family and friends and the teams of health professionals who treat them. METHODS: The survey was based on a questionnaire including 106 items and one open question, filled-in by a physician and the nurses of the hospital, together with the interviewer. RESULTS: Out of the 1495 patients hospitalised in the hospital centre (84% occupation), 114 patients were included in the study, i.e., 8% of the total number of patients present. Patients' mean age was of 70 (21

Assuntos
Cuidados Paliativos , Doente Terminal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Coleta de Dados , Interpretação Estatística de Dados , França , Hospitalização , Hospitais Universitários , Humanos , Pessoa de Meia-Idade , Inquéritos e Questionários , Organização Mundial da Saúde
13.
Vaccine ; 31(20): 2457-64, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23541621

RESUMO

A first-generation oral inactivated whole-cell enterotoxigenic Escherichia coli (ETEC) vaccine, comprising formalin-killed ETEC bacteria expressing different colonization factor (CF) antigens combined with cholera toxin B subunit (CTB), when tested in phase III studies did not significantly reduce overall (generally mild) ETEC diarrhea in travelers or children although it reduced more severe ETEC diarrhea in travelers by almost 80%. We have now developed a novel more immunogenic ETEC vaccine based on recombinant non-toxigenic E. coli strains engineered to express increased amounts of CF antigens, including CS6 as well as an ETEC-based B subunit protein (LCTBA), and the optional combination with a nontoxic double-mutant heat-labile toxin (LT) molecule (dmLT) as an adjuvant. Two test vaccines were prepared under GMP: (1) A prototype E. coli CFA/I-only formalin-killed whole-cell+LCTBA vaccine, and (2) A "complete" inactivated multivalent ETEC-CF (CFA/I, CS3, CS5 and CS6 antigens) whole-cell+LCTBA vaccine. These vaccines, when given intragastrically alone or together with dmLT in mice, were well tolerated and induced strong intestinal-mucosal IgA antibody responses as well as serum IgG and IgA responses to each of the vaccine CF antigens as well as to LT B subunit (LTB). Both mucosal and serum responses were further enhanced (adjuvanted) when the vaccines were co-administered with dmLT. We conclude that the new multivalent oral ETEC vaccine, both alone and especially in combination with the dmLT adjuvant, shows great promise for further testing in humans.


Assuntos
Adjuvantes Imunológicos , Toxinas Bacterianas/imunologia , Toxina da Cólera/imunologia , Escherichia coli Enterotoxigênica/imunologia , Enterotoxinas/imunologia , Proteínas de Escherichia coli/imunologia , Vacinas contra Escherichia coli/imunologia , Proteínas de Fímbrias/imunologia , Vacinas de Produtos Inativados/genética , Vacinas de Produtos Inativados/imunologia , Adjuvantes Imunológicos/administração & dosagem , Administração Oral , Animais , Formação de Anticorpos/imunologia , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Toxinas Bacterianas/administração & dosagem , Toxinas Bacterianas/genética , Toxina da Cólera/administração & dosagem , Toxina da Cólera/genética , Enterotoxinas/administração & dosagem , Enterotoxinas/genética , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/prevenção & controle , Proteínas de Escherichia coli/administração & dosagem , Proteínas de Escherichia coli/genética , Vacinas contra Escherichia coli/administração & dosagem , Vacinas contra Escherichia coli/efeitos adversos , Vacinas contra Escherichia coli/genética , Feminino , Proteínas de Fímbrias/genética , Imunidade nas Mucosas/imunologia , Imunoglobulina A/análise , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/análise , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Intestinos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Mutantes/administração & dosagem , Proteínas Mutantes/imunologia , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos
14.
Vaccine ; 31(8): 1163-70, 2013 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-23306362

RESUMO

We have developed a new oral vaccine against enterotoxigenic Escherichia coli (ETEC) diarrhea containing killed recombinant E. coli bacteria expressing increased levels of ETEC colonization factors (CFs) and a recombinant protein (LCTBA), i.e. a hybrid between the binding subunits of E. coli heat labile toxin (LTB) and cholera toxin (CTB). We describe a randomized, comparator controlled, double-blind phase I trial in 60 adult Swedish volunteers of a prototype of this vaccine. The safety and immunogenicity of the prototype vaccine, containing LCTBA and an E. coli strain overexpressing the colonization factor CFA/I, was compared to a previously developed oral ETEC vaccine, consisting of CTB and inactivated wild type ETEC bacteria expressing CFA/I (reference vaccine). Groups of volunteers were given two oral doses of either the prototype or the reference vaccine; the prototype vaccine was administered at the same or a fourfold higher dosage than the reference vaccine. The prototype vaccine was found to be safe and equally well-tolerated as the reference vaccine at either dosage tested. The prototype vaccine induced mucosal IgA (fecal secretory IgA and intestine-derived IgA antibody secreting cell) responses to both LTB and CFA/I, as well as serum IgA and IgG antibody responses to LTB. Immunization with LCTBA resulted in about twofold higher mucosal and systemic IgA responses against LTB than a comparable dose of CTB. The higher dose of the prototype vaccine induced significantly higher fecal and systemic IgA responses to LTB and fecal IgA responses to CFA/I than the reference vaccine. These results demonstrate that CF over-expression and inclusion of the LCTBA hybrid protein in an oral inactivated ETEC vaccine does not change the safety profile when compared to a previous generation of such a vaccine and that the prototype vaccine induces significant dose dependent mucosal immune responses against CFA/I and LTB.


Assuntos
Toxinas Bacterianas/metabolismo , Toxina da Cólera/metabolismo , Escherichia coli Enterotoxigênica/imunologia , Enterotoxinas/metabolismo , Proteínas de Escherichia coli/imunologia , Proteínas de Escherichia coli/metabolismo , Vacinas contra Escherichia coli/efeitos adversos , Vacinas contra Escherichia coli/imunologia , Proteínas de Fímbrias/imunologia , Adjuvantes Imunológicos/genética , Adjuvantes Imunológicos/metabolismo , Administração Oral , Adulto , Anticorpos Antibacterianos/análise , Anticorpos Antibacterianos/sangue , Toxinas Bacterianas/genética , Toxina da Cólera/genética , Colicinas , Método Duplo-Cego , Enterotoxinas/genética , Proteínas de Escherichia coli/genética , Vacinas contra Escherichia coli/administração & dosagem , Feminino , Proteínas de Fímbrias/genética , Experimentação Humana , Humanos , Imunidade nas Mucosas , Imunoglobulina A/análise , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/imunologia , Adulto Jovem
15.
Carbohydr Res ; 346(6): 872-6, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21392735

RESUMO

The structure of the repeating unit of the O-antigen polysaccharide from Shigella flexneri provisional serotype 88-893 has been determined. (1)H and (13)C NMR spectroscopy as well as 2D NMR experiments were employed to elucidate the structure. The carbohydrate part of the hexasaccharide repeating unit is identical to the previously elucidated structure of the O-polysaccharide from S. flexneri prov. serotype Y394. The O-antigen of S. flexneri prov. serotype 88-893 carries 0.7 mol O-acetyl group per repeating unit located at O-2 of the 3-substituted rhamnosyl residue, as identified by H2BC and BS-CT-HMBC NMR experiments. The O-antigen polysaccharide is composed of hexasaccharide repeating units with the following structure: →2)-α-L-Rhap-(1→2)-α-L-Rhap-(1→3)-α-L-Rhap2Ac-(1→3)[α-D-Glcp-(1→2)-α-D-Glcp-(1→4)]-ß-D-GlcpNAc-(1→. Serological studies showed that type antigens for the two provisional serotypes are identical; in addition 88-893 expresses S. flexneri group factor 6 antigen. We propose that provisional serotypes Y394 and 88-893 be designated as two new serotypes 7a and 7b, respectively, in the S. flexneri typing scheme.


Assuntos
Antígenos O/química , Shigella flexneri/química , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Dados de Sequência Molecular , Sorotipagem
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