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1.
Eur J Clin Microbiol Infect Dis ; 40(1): 193-195, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32666481

RESUMO

PURPOSE: PCR on a nasopharyngeal sample is the reference method for the detection of SARS-nCoV-2. However, combined throat/nasal sampling as a testing method has several advantages. We compared the combined throat/nasal sampling with nasopharyngeal sampling for detection of SARS-CoV-2 in healthcare workers suspected of COVID-19. METHODS: In 107 healthcare workers with symptoms of COVID-19, combined throat/nasal sampling and nasopharyngeal sampling was performed. Detection of SARS-CoV-2 was performed by RT-PCR targeting. RESULTS: A total of 80 healthcare workers (74.8%) tested negative with both sampling methods, and 25 healthcare workers (23.4%) tested positive with both sampling methods. There were two discrepant results with positive PCR in combined throat/nasal swabs and negative PCR in nasopharyngeal swabs (1.9%). The κ index for concordance between the 2 sampling methods was high (0.95). The median cycle threshold (Ct) value of PCR on nasopharyngeal samples was significantly lower than the Ct value of PCR on combined throat/nasal samples (19 (IQR 17-20) versus 21 (IQR 18-29) cycles, p value 0.01). CONCLUSION: Combined throat/nasal swabs yield a similar sensitivity to detect SARS-CoV-2 as nasopharyngeal swabs and are a good alternative sampling method, despite a lower Ct value for the nasopharyngeal samples.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Nasofaringe/virologia , Nariz/virologia , Faringe/virologia , SARS-CoV-2/isolamento & purificação , Manejo de Espécimes/métodos , Adulto , Pessoal de Saúde/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , RNA Viral/isolamento & purificação , SARS-CoV-2/genética , Adulto Jovem
2.
Nat Commun ; 9(1): 3709, 2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30213944

RESUMO

The radiant energy budget and internal heat are fundamental properties of giant planets, but precise determination of these properties remains a challenge. Here, we report measurements of Jupiter's radiant energy budget and internal heat based on Cassini multi-instrument observations. Our findings reveal that Jupiter's Bond albedo and internal heat, 0.503 ± 0.012 and 7.485 ± 0.160 W m-2 respectively, are significantly larger than 0.343 ± 0.032 and 5.444 ± 0.425 Wm-2, the previous best estimates. The new results help constrain and improve the current evolutionary theories and models for Jupiter. Furthermore, the significant wavelength dependency of Jupiter's albedo implies that the radiant energy budgets and internal heat of the other giant planets in our solar system should be re-examined. Finally, the data sets of Jupiter's characteristics of reflective solar spectral irradiance provide an observational basis for the models of giant exoplanets.

3.
Nat Commun ; 9(1): 3564, 2018 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-30177694

RESUMO

Saturn's polar stratosphere exhibits the seasonal growth and dissipation of broad, warm vortices poleward of ~75° latitude, which are strongest in the summer and absent in winter. The longevity of the exploration of the Saturn system by Cassini allows the use of infrared spectroscopy to trace the formation of the North Polar Stratospheric Vortex (NPSV), a region of enhanced temperatures and elevated hydrocarbon abundances at millibar pressures. We constrain the timescales of stratospheric vortex formation and dissipation in both hemispheres. Although the NPSV formed during late northern spring, by the end of Cassini's reconnaissance (shortly after northern summer solstice), it still did not display the contrasts in temperature and composition that were evident at the south pole during southern summer. The newly formed NPSV was bounded by a strengthening stratospheric thermal gradient near 78°N. The emergent boundary was hexagonal, suggesting that the Rossby wave responsible for Saturn's long-lived polar hexagon-which was previously expected to be trapped in the troposphere-can influence the stratospheric temperatures some 300 km above Saturn's clouds.

4.
Astrophys J Lett ; 854(2)2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32373309

RESUMO

In this paper we report the monitoring of seasonal evolution near Titan's poles. We find Titan's south pole to exhibit since 2010 a strong temperature decrease and a dramatic enhancement of several trace species such as complex hydrocarbons and nitriles (HC3N and C6H6 in particular) previously only observed at high northern latitudes (Coustenis et al. 2016 and references therein). This results from the seasonal change on Titan going from winter (2002) to summer (2017) in the north and, at the same time, the onset of winter in the south pole. During this transition period atmospheric components with longer chemical lifetimes linger in the north undergoing slow photochemical destruction, while those with shorter lifetimes decrease and reappear in the south. An opposite effect was expected in the north, but not observed with certainty until now. We present here an analysis of high-resolution nadir spectra acquired by Cassini/CIRS at in the past years and describe the temperature and composition variations near Titan's poles. From 2013 until 2016, the northern polar region has shown a temperature increase of 10 K, while the south has shown a more significant decrease (up to 25 K) in a similar period of time. While the south polar region is continuously enhanced since about 2012, the chemical content in the north is finally showing a clear depletion for most molecules only since 2015. This is indicative of a non-symmetrical response to the seasons in Titan's stratosphere that can set constraints on photochemical and GCM models.

5.
Appl Opt ; 56(18): 5274-5294, 2017 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29047582

RESUMO

The Cassini spacecraft orbiting Saturn carries the composite infrared spectrometer (CIRS) designed to study thermal emission from Saturn and its rings and moons. CIRS, a Fourier transform spectrometer, is an indispensable part of the payload providing unique measurements and important synergies with the other instruments. It takes full advantage of Cassini's 13-year-long mission and surpasses the capabilities of previous spectrometers on Voyager 1 and 2. The instrument, consisting of two interferometers sharing a telescope and a scan mechanism, covers over a factor of 100 in wavelength in the mid and far infrared. It is used to study temperature, composition, structure, and dynamics of the atmospheres of Jupiter, Saturn, and Titan, the rings of Saturn, and surfaces of the icy moons. CIRS has returned a large volume of scientific results, the culmination of over 30 years of instrument development, operation, data calibration, and analysis. As Cassini and CIRS reach the end of their mission in 2017, we expect that archived spectra will be used by scientists for many years to come.

7.
Allergy ; 72(7): 1096-1104, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28032359

RESUMO

BACKGROUND: Most studies on the relationship between helminth infections and atopic disorders have been conducted in (sub)tropical developing countries where exposure to multiple parasites and lifestyle can confound the relationship. We aimed to study the relationship between infection with the fish-borne helminth Opishorchis felineus and specific IgE, skin prick testing, and atopic symptoms in Western Siberia, with lifestyle and hygiene standards of a developed country. METHODS: Schoolchildren aged 7-11 years were sampled from one urban and two rural regions. Skin prick tests (SPT) and specific IgE (sIgE) against food and aeroallergens were measured, and data on allergic symptoms and on demographic and socioeconomic factors were collected by questionnaire. Diagnosis of opisthorchiasis was based on PCR performed on stool samples. RESULTS: Of the 732 children included, 34.9% had opisthorchiasis. The sensitization to any allergen when estimated by positive SPT was 12.8%, while much higher, 24.0%, when measured by sIgE. Atopic symptoms in the past year (flexural eczema and/or rhinoconjunctivitis) were reported in 12.4% of the children. SPT was positively related to flexural eczema and rhinoconjunctivitis, but not to wheezing. Opisthorchiasis showed association with lower SPT response, as well as borderline association with low IgE reactivity to any allergen. However, the effect of opisthorchiasis on SPT response was not mediated by IgE, suggesting that opisthorchiasis influences SPT response through another mechanism. Opisthorchiasis also showed borderline association with lower atopic symptoms. CONCLUSIONS: There is a negative association between a chronic helminth infection and skin prick test reactivity even in a developed country.


Assuntos
Hipersensibilidade Imediata/diagnóstico , Hipersensibilidade Imediata/etiologia , Opistorquíase/imunologia , Opisthorchis/imunologia , Testes Cutâneos/normas , Animais , Especificidade de Anticorpos/imunologia , Criança , Feminino , Humanos , Hipersensibilidade Imediata/epidemiologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Masculino , Razão de Chances , Opistorquíase/complicações , Opistorquíase/epidemiologia , Opistorquíase/parasitologia , Opisthorchis/genética , Prevalência , Fatores de Risco , População Rural , Federação Russa/epidemiologia , Avaliação de Sintomas
8.
Vet J ; 196(3): 439-44, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23177539

RESUMO

The feasibility of using bead-based suspension arrays to detect serological evidence of Trichinella in pigs was assessed. Trichinella spiralis excretory-secretory antigen was covalently coupled to paramagnetic beads and used to bind serum antibodies, which were subsequently detected using anti-swine antibody. The assay was evaluated by testing pig sera from farms where trichinellosis was endemic and comparing the results with those obtained using two commercially available ELISAs. With cut-offs established by receiver operating characteristic (ROC) analysis, digestion-negative sera from a Trichinella-free population of pigs were deemed seronegative. When anti-swine antibody was replaced with protein A/G, higher test sensitivity (94% vs. 88%) at similar test specificity (95%), was achieved. The potential use of this assay in species other than swine was also demonstrated by testing human sera.


Assuntos
Testes Sorológicos/veterinária , Doenças dos Suínos/diagnóstico , Trichinella/isolamento & purificação , Triquinelose/veterinária , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Sensibilidade e Especificidade , Suínos , Doenças dos Suínos/sangue , Doenças dos Suínos/parasitologia , Triquinelose/sangue , Triquinelose/diagnóstico , Triquinelose/parasitologia
9.
Philos Trans A Math Phys Eng Sci ; 367(1889): 649-64, 2009 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-19073460

RESUMO

Titan's middle atmosphere is characterized by cyclostrophic winds and strong seasonal modulation. Cassini CIRS observations, obtained in northern winter, indicate that the stratosphere near 1mbar is warmest at low latitudes, with the South Pole a few degrees colder and the North Pole approximately 20K colder. Associated with the cold northern temperatures are strong circumpolar winds with speeds as high as 190ms-1. Within this vortex, the mixing ratios of several organic gases are enhanced relative to those at low latitudes. Comparison with Voyager thermal infrared measurements, obtained 25 years ago in northern spring, suggests that the enhancement currently observed will increase as the winter progresses. The stratopause height increases from 0.1mbar near the equator to 0.01mbar near the North Pole, where it is the warmest part of the atmosphere, greater than 200K. This implies subsidence at the pole, which is consistent with the enhanced organics observed. Condensate features, several still not identified, are also apparent in the infrared spectra at high northern latitudes. In many ways, the winter vortex observed on Titan, with cyclostrophic winds, resembles the polar winter vortices on the Earth, where the mean winds are geostrophic.

10.
Science ; 319(5859): 79-81, 2008 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-18174438

RESUMO

Saturn's poles exhibit an unexpected symmetry in hot, cyclonic polar vortices, despite huge seasonal differences in solar flux. The cores of both vortices are depleted in phosphine gas, probably resulting from subsidence of air into the troposphere. The warm cores are present throughout the upper troposphere and stratosphere at both poles. The thermal structure associated with the marked hexagonal polar jet at 77 degrees N has been observed for the first time. Both the warm cyclonic belt at 79 degrees N and the cold anticyclonic zone at 75 degrees N exhibit the hexagonal structure.

11.
J Clin Microbiol ; 44(5): 1867-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16672425

RESUMO

The main mechanisms by which Campylobacter jejuni causes diarrhea are unknown. In contrast to a recent communication, we report here the absence of an association with the plasmid pVir in patients infected with C. jejuni who developed bloody diarrhea in The Netherlands, and we suggest a role for other virulence determinants.


Assuntos
Infecções por Campylobacter/microbiologia , Campylobacter jejuni/genética , Enterite/microbiologia , Infecções por Campylobacter/epidemiologia , Campylobacter jejuni/isolamento & purificação , Campylobacter jejuni/patogenicidade , Diarreia/microbiologia , Hemorragia Gastrointestinal/microbiologia , Genes Bacterianos , Humanos , Epidemiologia Molecular , Países Baixos/epidemiologia , Plasmídeos/genética , Plasmídeos/isolamento & purificação , Virulência/genética
12.
Science ; 308(5724): 975-8, 2005 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15894528

RESUMO

Temperatures obtained from early Cassini infrared observations of Titan show a stratopause at an altitude of 310 kilometers (and 186 kelvin at 15 degrees S). Stratospheric temperatures are coldest in the winter northern hemisphere, with zonal winds reaching 160 meters per second. The concentrations of several stratospheric organic compounds are enhanced at mid- and high northern latitudes, and the strong zonal winds may inhibit mixing between these latitudes and the rest of Titan. Above the south pole, temperatures in the stratosphere are 4 to 5 kelvin cooler than at the equator. The stratospheric mole fractions of methane and carbon monoxide are (1.6 +/- 0.5) x 10(-2) and (4.5 +/- 1.5) x 10(-5), respectively.


Assuntos
Hidrocarbonetos , Metano , Nitrilas , Saturno , Atmosfera , Monóxido de Carbono , Meio Ambiente Extraterreno , Astronave , Temperatura , Vento
13.
Science ; 307(5713): 1247-51, 2005 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-15618486

RESUMO

Stratospheric temperatures on Saturn imply a strong decay of the equatorial winds with altitude. If the decrease in winds reported from recent Hubble Space Telescope images is not a temporal change, then the features tracked must have been at least 130 kilometers higher than in earlier studies. Saturn's south polar stratosphere is warmer than predicted from simple radiative models. The C/H ratio on Saturn is seven times solar, twice Jupiter's. Saturn's ring temperatures have radial variations down to the smallest scale resolved (100 kilometers). Diurnal surface temperature variations on Phoebe suggest a more porous regolith than on the jovian satellites.


Assuntos
Saturno , Atmosfera , Carbono , Meio Ambiente Extraterreno , Hidrogênio , Metano , Astronave , Análise Espectral , Temperatura , Vento
14.
Science ; 305(5690): 1582-6, 2004 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-15319491

RESUMO

The Composite Infrared Spectrometer observed Jupiter in the thermal infrared during the swing-by of the Cassini spacecraft. Results include the detection of two new stratospheric species, the methyl radical and diacetylene, gaseous species present in the north and south auroral infrared hot spots; determination of the variations with latitude of acetylene and ethane, the latter a tracer of atmospheric motion; observations of unexpected spatial distributions of carbon dioxide and hydrogen cyanide, both considered to be products of comet Shoemaker-Levy 9 impacts; characterization of the morphology of the auroral infrared hot spot acetylene emission; and a new evaluation of the energetics of the northern auroral infrared hot spot.


Assuntos
Dióxido de Carbono , Hidrocarbonetos , Cianeto de Hidrogênio , Júpiter , Acetileno , Atmosfera , Etano , Meio Ambiente Extraterreno , Astronave , Análise Espectral , Temperatura
15.
Nature ; 427(6970): 132-5, 2004 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-14712270

RESUMO

The Earth's equatorial stratosphere shows oscillations in which the east-west winds reverse direction and the temperatures change cyclically with a period of about two years. This phenomenon, called the quasi-biennial oscillation, also affects the dynamics of the mid- and high-latitude stratosphere and weather in the lower atmosphere. Ground-based observations have suggested that similar temperature oscillations (with a 4-5-yr cycle) occur on Jupiter, but these data suffer from poor vertical resolution and Jupiter's stratospheric wind velocities have not yet been determined. Here we report maps of temperatures and winds with high spatial resolution, obtained from spacecraft measurements of infrared spectra of Jupiter's stratosphere. We find an intense, high-altitude equatorial jet with a speed of approximately 140 m s(-1), whose spatial structure resembles that of a quasi-quadrennial oscillation. Wave activity in the stratosphere also appears analogous to that occurring on Earth. A strong interaction between Jupiter and its plasma environment produces hot spots in its upper atmosphere and stratosphere near its poles, and the temperature maps define the penetration of the hot spots into the stratosphere.

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