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1.
Phys Rev Lett ; 127(15): 151301, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34678017

RESUMO

We present results from an analysis of all data taken by the BICEP2, Keck Array, and BICEP3 CMB polarization experiments up to and including the 2018 observing season. We add additional Keck Array observations at 220 GHz and BICEP3 observations at 95 GHz to the previous 95/150/220 GHz dataset. The Q/U maps now reach depths of 2.8, 2.8, and 8.8 µK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈600 square degrees at 95 GHz and ≈400 square degrees at 150 and 220 GHz. The 220 GHz maps now achieve a signal-to-noise ratio on polarized dust emission exceeding that of Planck at 353 GHz. We take auto- and cross-spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz and evaluate the joint likelihood of the spectra versus a multicomponent model of lensed ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and no longer requires a prior on the frequency spectral index of the dust emission taken from measurements on other regions of the sky. This model is an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.036 at 95% confidence. Running maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.009. These are the strongest constraints to date on primordial gravitational waves.

2.
Phys Rev Lett ; 121(22): 221301, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30547645

RESUMO

We present results from an analysis of all data taken by the bicep2/Keck CMB polarization experiments up to and including the 2015 observing season. This includes the first Keck Array observations at 220 GHz and additional observations at 95 and 150 GHz. The Q and U maps reach depths of 5.2, 2.9, and 26 µK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈400 square degrees. The 220 GHz maps achieve a signal to noise on polarized dust emission approximately equal to that of Planck at 353 GHz. We take auto and cross spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz. We evaluate the joint likelihood of the spectra versus a multicomponent model of lensed-ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and we impose priors on some of these using external information from Planck and WMAP derived from larger regions of sky. The model is shown to be an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.07 at 95% confidence, which tightens to r_{0.05}<0.06 in conjunction with Planck temperature measurements and other data. The lensing signal is detected at 8.8σ significance. Running a maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.020. These are the strongest constraints to date on primordial gravitational waves.

3.
Phys Rev Lett ; 116(3): 031302, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26849583

RESUMO

We present results from an analysis of all data taken by the BICEP2 and Keck Array cosmic microwave background (CMB) polarization experiments up to and including the 2014 observing season. This includes the first Keck Array observations at 95 GHz. The maps reach a depth of 50 nK deg in Stokes Q and U in the 150 GHz band and 127 nK deg in the 95 GHz band. We take auto- and cross-spectra between these maps and publicly available maps from WMAP and Planck at frequencies from 23 to 353 GHz. An excess over lensed ΛCDM is detected at modest significance in the 95×150 BB spectrum, and is consistent with the dust contribution expected from our previous work. No significant evidence for synchrotron emission is found in spectra such as 23×95, or for correlation between the dust and synchrotron sky patterns in spectra such as 23×353. We take the likelihood of all the spectra for a multicomponent model including lensed ΛCDM, dust, synchrotron, and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r) using priors on the frequency spectral behaviors of dust and synchrotron emission from previous analyses of WMAP and Planck data in other regions of the sky. This analysis yields an upper limit r_{0.05}<0.09 at 95% confidence, which is robust to variations explored in analysis and priors. Combining these B-mode results with the (more model-dependent) constraints from Planck analysis of CMB temperature plus baryon acoustic oscillations and other data yields a combined limit r_{0.05}<0.07 at 95% confidence. These are the strongest constraints to date on inflationary gravitational waves.

4.
Phys Rev Lett ; 112(24): 241101, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24996078

RESUMO

We report results from the BICEP2 experiment, a cosmic microwave background (CMB) polarimeter specifically designed to search for the signal of inflationary gravitational waves in the B-mode power spectrum around ℓ∼80. The telescope comprised a 26 cm aperture all-cold refracting optical system equipped with a focal plane of 512 antenna coupled transition edge sensor 150 GHz bolometers each with temperature sensitivity of ≈300 µK(CMB)√s. BICEP2 observed from the South Pole for three seasons from 2010 to 2012. A low-foreground region of sky with an effective area of 380 square deg was observed to a depth of 87 nK deg in Stokes Q and U. In this paper we describe the observations, data reduction, maps, simulations, and results. We find an excess of B-mode power over the base lensed-ΛCDM expectation in the range 30 < ℓ < 150, inconsistent with the null hypothesis at a significance of >5σ. Through jackknife tests and simulations based on detailed calibration measurements we show that systematic contamination is much smaller than the observed excess. Cross correlating against WMAP 23 GHz maps we find that Galactic synchrotron makes a negligible contribution to the observed signal. We also examine a number of available models of polarized dust emission and find that at their default parameter values they predict power ∼(5-10)× smaller than the observed excess signal (with no significant cross-correlation with our maps). However, these models are not sufficiently constrained by external public data to exclude the possibility of dust emission bright enough to explain the entire excess signal. Cross correlating BICEP2 against 100 GHz maps from the BICEP1 experiment, the excess signal is confirmed with 3σ significance and its spectral index is found to be consistent with that of the CMB, disfavoring dust at 1.7σ. The observed B-mode power spectrum is well fit by a lensed-ΛCDM+tensor theoretical model with tensor-to-scalar ratio r = 0.20_(-0.05)(+0.07), with r = 0 disfavored at 7.0σ. Accounting for the contribution of foreground, dust will shift this value downward by an amount which will be better constrained with upcoming data sets.

5.
Phys Rev Lett ; 111(25): 251301, 2013 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-24483735

RESUMO

We report results of a search for weakly interacting massive particles (WIMPS) with the silicon detectors of the CDMS II experiment. This blind analysis of 140.2 kg day of data taken between July 2007 and September 2008 revealed three WIMP-candidate events with a surface-event background estimate of 0.41(-0.08)(+0.20)(stat)(-0.24)(+0.28)(syst). Other known backgrounds from neutrons and 206Pb are limited to <0.13 and <0.08 events at the 90% confidence level, respectively. The exposure of this analysis is equivalent to 23.4 kg day for a recoil energy range of 7-100 keV for a WIMP of mass 10 GeV/c2. The probability that the known backgrounds would produce three or more events in the signal region is 5.4%. A profile likelihood ratio test of the three events that includes the measured recoil energies gives a 0.19% probability for the known-background-only hypothesis when tested against the alternative WIMP+background hypothesis. The highest likelihood occurs for a WIMP mass of 8.6 GeV/c2 and WIMP-nucleon cross section of 1.9×10(-41) cm2.

6.
Phys Rev Lett ; 106(13): 131302, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21517371

RESUMO

We report results from a reanalysis of data from the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory. Data taken between October 2006 and September 2008 using eight germanium detectors are reanalyzed with a lowered, 2 keV recoil-energy threshold, to give increased sensitivity to interactions from weakly interacting massive particles (WIMPs) with masses below ∼10 GeV/c(2). This analysis provides stronger constraints than previous CDMS II results for WIMP masses below 9 GeV/c(2) and excludes parameter space associated with possible low-mass WIMP signals from the DAMA/LIBRA and CoGeNT experiments.

7.
Phys Rev Lett ; 103(14): 141802, 2009 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-19905561

RESUMO

We report on the first axion search results from the Cryogenic Dark Matter Search (CDMS) experiment at the Soudan Underground Laboratory. An energy threshold of 2 keV for electron-recoil events allows a search for possible solar axion conversion into photons or local galactic axion conversion into electrons in the germanium crystal detectors. The solar axion search sets an upper limit on the Primakov coupling g(agammagamma) of 2.4x10(-9) GeV-1 at the 95% confidence level for an axion mass less than 0.1 keV/c2. This limit benefits from the first precise measurement of the absolute crystal plane orientations in this type of experiment. The galactic axion search analysis sets a world-leading experimental upper limit on the axioelectric coupling g(aee) of 1.4x10(-12) at the 90% confidence level for an axion mass of 2.5 keV/c2.

8.
Homo ; 59(6): 405-27, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19027113

RESUMO

The contact of inland and coastal prehistoric groups in Brazil is believed to have been restricted to regions with no geographical barrier, as is the case in the Ribeira de Iguape valley. The inland osteological collection from the riverine shellmound Moraes (5800-4500 BP) represents a unique opportunity to test this assumption for this region. Despite cultural similarities between riverine and coastal shellmounds, important ecological and site distribution differences are expected to impact on lifestyle. The purpose of this study is thus to document and interpret health and lifestyle indicators in Moraes in comparison to coastal shellmound groups. Specifically we test if the rare evidence of fish and mollusc remains in the riverine shellmound led to (a) higher caries rates and (b) lower auditory exostosis frequency and (c) if the small size of the riverine shellmound translates into reduced demographic density and thus rarity of communicable infectious diseases. Of the three hypotheses, (a) was confirmed, (b) was rejected and (c) was partly rejected. Bioanthropological similarities between Moraes and coastal shellmounds include auditory exostoses with equally high frequencies; significantly more frequent osteoarthritis in upper than in lower limbs; cranial and dental morphological affinities and low frequencies of violent trauma. However, there are also important differences: Moraes subsisted on a much broader protein diet and consumed more cariogenic food, but showed a stature even shorter than coastal groups. Thus, despite the contact also suggested by treponematoses in both site types, there was enough time for the people at the riverine site to adapt to local conditions.


Assuntos
Ecossistema , Estilo de Vida , Adulto , Idoso , Animais , Brasil , Sepultamento , Feminino , Peixes , Humanos , Masculino , Pessoa de Meia-Idade , Moluscos , Estado Nutricional , Paleontologia , Paleopatologia , Dente/anatomia & histologia , Adulto Jovem
9.
Rev Laryngol Otol Rhinol (Bord) ; 124(1): 31-7, 2003.
Artigo em Francês | MEDLINE | ID: mdl-12934440

RESUMO

INTRODUCTION: Stapes gusher means the leakage of perilymphatic liquid when opening the perilymphatic cistern. The perilymphatic liquid with a high pressure gushes with a great flow out of the cistern when the stapedotomy is executed. Otosclerosis surgery sometime brings to light abnormal contact between the inner ear and the sub-arachnoidian spaces in patients who didn't presented ear malformations. It's a very rare event (1/1000) which is different from a much more common and more moderate form of perilymphatic liquids high pressure (1/200). About 4 clinical observations, we compared our experience with other authors in specialist reviews. PURPOSE OF THE STUDY: About four observations, we confronted our experience with that of the literature. MATERIAL AND METHODS: Retrospective study between 1971 and 1998. It was about 3 males and 1 female, without antecedent except one of them who had been operated 5 years before for the opposite ear without gusher but without good audiometric result. They presented a conductive deafness with no answer of the stapedial reflex. We had 4 geysers during the platinotomia which were sealed with some connective tissue. RESULTS: Two patients had a post operative complete sensory hearing loss, one, a sensitive decline of the conduction thresholds (average 50 dB), the last one kept his bone conduction level with a mild sensory hearing loss. The most recent case had a scanner preoperatively which had not shown abnormality except for the focus of otosclerosis. DISCUSSION: Perilymphatic gusher is an unpredictable event that can not be diagnosed before the surgery, nether with clinical facts nor radiological elements. This involves serious consequences concerning not only the continuation of the surgical operation and the prognostic of the hearing but also concerning the danger of secondary meningeal infections. The best way to proceed in case of favourable cases consists in fitting the ossicular prothesis into the stapedotomy, when it's not to wide. Pieces of muscle can be used in some cases, taped on with biologic glu. Various techniques are used to lower the pression of the cerebrospinal liquid: hypertonic solutes, diuretic drugs, lumbar diversion. In all cases, it is necessary to start a wide spectrum antibiotic treatment and a vaccination against pneumococcis. CONCLUSION: The surgeon has to know all the option of the treatment when confronted with this situation in order to try to avoid tricky defect of the inner ear.


Assuntos
Otorreia de Líquido Cefalorraquidiano/etiologia , Otorreia de Líquido Cefalorraquidiano/fisiopatologia , Otosclerose/cirurgia , Perilinfa/fisiologia , Complicações Pós-Operatórias , Adulto , Audiometria/métodos , Feminino , Perda Auditiva Condutiva/diagnóstico , Perda Auditiva Condutiva/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Otosclerose/diagnóstico por imagem , Otosclerose/patologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Estribo/fisiopatologia , Tomografia Computadorizada por Raios X
10.
Rev Laryngol Otol Rhinol (Bord) ; 117(2): 75-8, 1996.
Artigo em Francês | MEDLINE | ID: mdl-8959923

RESUMO

Cannot simply be considered as a nociception phenomenon: it is more complex than a simple transmission system that conveys this information to the cerebral cortex. It is mainly a psychological event. Numerous regulating and inhibiting effects on incoming pain signals exist, for the most part located in spinal and thalamic areas; only half of these are morphine-dependent. Knowledge of these allows a better approach to chronic pain, using not only medication but also other techniques such as physiotherapy and music therapy analgesia.


Assuntos
Dor/fisiopatologia , Humanos , Nociceptores/anatomia & histologia , Nociceptores/fisiologia , Medula Espinal/anatomia & histologia , Medula Espinal/fisiologia , Tratos Espinotalâmicos/anatomia & histologia , Tálamo/anatomia & histologia , Tálamo/fisiologia
11.
Rev Laryngol Otol Rhinol (Bord) ; 117(2): 79-82, 1996.
Artigo em Francês | MEDLINE | ID: mdl-8959924

RESUMO

After recalling the components and the factors influencing the pain, are stated the main reasons which needs for the evaluation of the pain. The different methods allowing an evaluation of the pain are then described with their advantages and disadvantages. These methods are based on, on one hand on questonary with as a support the use of different mono or multidimensional scales and on the other hand a clinical examination. The goal of this proceeding is to elaborate a scale of the pain for a better adaptation of it's therapy.


Assuntos
Medição da Dor , Humanos , Autoavaliação (Psicologia) , Inquéritos e Questionários
12.
Rev Laryngol Otol Rhinol (Bord) ; 120(5): 323-6, 1999.
Artigo em Francês | MEDLINE | ID: mdl-10769566

RESUMO

After having recalled the different physiologic hypothesis of the tinnitus and those more documented of the pain, the authors noted certain parallelious in the therapeutical approaches of these tow subjectives sensations. They put the emphasis on the necessity, like with pain, to treat the tinnitus as fast as possible in order to avoid a centralisation by actionning of neuronal autonomized circuits.


Assuntos
Dor/tratamento farmacológico , Dor/etiologia , Zumbido/complicações , Humanos
13.
Science ; 327(5973): 1619-21, 2010 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-20150446

RESUMO

Astrophysical observations indicate that dark matter constitutes most of the mass in our universe, but its nature remains unknown. Over the past decade, the Cryogenic Dark Matter Search (CDMS II) experiment has provided world-leading sensitivity for the direct detection of weakly interacting massive particle (WIMP) dark matter. The final exposure of our low-temperature germanium particle detectors at the Soudan Underground Laboratory yielded two candidate events, with an expected background of 0.9 +/- 0.2 events. This is not statistically significant evidence for a WIMP signal. The combined CDMS II data place the strongest constraints on the WIMP-nucleon spin-independent scattering cross section for a wide range of WIMP masses and exclude new parameter space in inelastic dark matter models.

15.
Phys Rev Lett ; 102(1): 011301, 2009 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-19257177

RESUMO

We report results from the Cryogenic Dark Matter Search at the Soudan Underground Laboratory (CDMS II) featuring the full complement of 30 detectors. A blind analysis of data taken between October 2006 and July 2007 sets an upper limit on the weakly interacting massive particle (WIMP) nucleon spin-independent cross section of 6.6x10;{-44} cm;{2} (4.6x10;{-44} cm;{2} when combined with previous CDMS II data) at the 90% confidence level for a WIMP mass of 60 GeV/c;{2}. This achieves the best sensitivity for dark matter WIMPs with masses above 44 GeV/c;{2}, and significantly restricts the parameter space for some favored supersymmetric models.

16.
Phys Rev Lett ; 96(1): 011302, 2006 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-16486434

RESUMO

We report new results from the Cryogenic Dark Matter Search (CDMS II) at the Soudan Underground Laboratory. Two towers, each consisting of six detectors, were operated for 74.5 live days, giving spectrum-weighted exposures of 34 (12) kg d for the Ge (Si) targets after cuts, averaged over recoil energies 10-100 keV for a weakly interacting massive particle (WIMP) mass of 60 GeV/c2. A blind analysis was conducted, incorporating improved techniques for rejecting surface events. No WIMP signal exceeding expected backgrounds was observed. When combined with our previous results from Soudan, the 90% C.L. upper limit on the spin-independent WIMP-nucleon cross section is 1.6 x 10(-43) cm2 from Ge and 3 x 10(-42) cm2 from Si, for a WIMP mass of 60 GeV/c2. The combined limit from Ge (Si) is a factor of 2.5 (10) lower than our previous results and constrains predictions of supersymmetric models.

17.
Appl Opt ; 14(12): 3007-11, 1975 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20155143

RESUMO

A cell with two identical pairs of electrodes oriented at 90 degrees is examined. When both elements are submitted to the same dc voltage and to two ac voltages having the same amplitude but phase-shifted by 180 degrees , the birefringence of the cell is proportional to the ac voltage as in a Pockels cell. Modulation experiments on the cell containing deionized nitrobenzene are presented and analogies and differences with Pockels cells are emphasized.

18.
Ann Radiol (Paris) ; 35(4): 212-6, 1992.
Artigo em Francês | MEDLINE | ID: mdl-1288388

RESUMO

Authors present a case of cystic lymphangioma of the neck in an adult patient. Cystic lymphangioma of the neck can simulate other benign lesions and occasionally extend into the mediastinum. Using computed tomography and ultrasound, the authors are able to confirm the suspected diagnosis, exclude other diagnostic considerations, and demonstrate absence of mediastinal extension. Opportunity of such diagnosis in adult is no frequent.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Linfangioma/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Humanos , Masculino , Ultrassonografia
19.
Phys Rev Lett ; 93(21): 211301, 2004 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-15600991

RESUMO

We report the first results from a search for weakly interacting massive particles (WIMPs) in the Cryogenic Dark Matter Search experiment at the Soudan Underground Laboratory. Four Ge and two Si detectors were operated for 52.6 live days, providing 19.4 kg d of Ge net exposure after cuts for recoil energies between 10 and 100 keV. A blind analysis was performed using only calibration data to define the energy threshold and selection criteria for nuclear-recoil candidates. Using the standard dark-matter halo and nuclear-physics WIMP model, these data set the world's lowest exclusion limits on the coherent WIMP-nucleon scalar cross section for all WIMP masses above 15 GeV/c2, ruling out a significant range of neutralino supersymmetric models. The minimum of this limit curve at the 90% C.L. is 4 x 10(-43) cm2 at a WIMP mass of 60 GeV/c2.

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