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1.
Sci Rep ; 13(1): 21965, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-38081902

RESUMO

The transition to farming brought on a series of important changes in human society, lifestyle, diet and health. The human bioarchaeology of the agricultural transition has received much attention, however, relatively few studies have directly tested the interrelationship between individual lifestyle factors and their implications for understanding life history changes among the first farmers. We investigate the interplay between skeletal growth, diet, physical activity and population size across 30,000 years in the central Mediterranean through a 'big data' cross-analysis of osteological data related to stature (n = 361), body mass (n = 334) and long bone biomechanics (n = 481), carbon (δ13C) and nitrogen (δ15N) stable isotopes (n = 1986 human, n = 475 animal) and radiocarbon dates (n = 5263). We present the observed trends on a continuous timescale in order to avoid grouping our data into assigned 'time periods', thus achieving greater resolution and chronological control over our analysis. The results identify important changes in human life history strategies associated with the first farmers, but also highlight the long-term nature of these trends in the millennia either side of the agricultural transition. The integration of these different data is an important step towards disentangling the complex relationship between demography, diet and health, and reconstruct life history changes within a southern European context. We believe the methodological approach adopted here has broader global implications for bioarchaeological studies of human adaptation more generally.


Assuntos
Agricultura , Dieta , Animais , Humanos , Osso e Ossos , Isótopos , Dinâmica Populacional , Isótopos de Nitrogênio , Isótopos de Carbono
2.
Nature ; 545(7655): 457-461, 2017 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-28541326

RESUMO

The existence of massive (1011 solar masses) elliptical galaxies by redshift z ≈ 4 (refs 1, 2, 3; when the Universe was 1.5 billion years old) necessitates the presence of galaxies with star-formation rates exceeding 100 solar masses per year at z > 6 (corresponding to an age of the Universe of less than 1 billion years). Surveys have discovered hundreds of galaxies at these early cosmic epochs, but their star-formation rates are more than an order of magnitude lower. The only known galaxies with very high star-formation rates at z > 6 are, with one exception, the host galaxies of quasars, but these galaxies also host accreting supermassive (more than 109 solar masses) black holes, which probably affect the properties of the galaxies. Here we report observations of an emission line of singly ionized carbon ([C ii] at a wavelength of 158 micrometres) in four galaxies at z > 6 that are companions of quasars, with velocity offsets of less than 600 kilometres per second and linear offsets of less than 100 kiloparsecs. The discovery of these four galaxies was serendipitous; they are close to their companion quasars and appear bright in the far-infrared. On the basis of the [C ii] measurements, we estimate star-formation rates in the companions of more than 100 solar masses per year. These sources are similar to the host galaxies of the quasars in [C ii] brightness, linewidth and implied dynamical mass, but do not show evidence for accreting supermassive black holes. Similar systems have previously been found at lower redshift. We find such close companions in four out of the twenty-five z > 6 quasars surveyed, a fraction that needs to be accounted for in simulations. If they are representative of the bright end of the [C ii] luminosity function, then they can account for the population of massive elliptical galaxies at z ≈ 4 in terms of the density of cosmic space.

3.
World J Microbiol Biotechnol ; 33(6): 128, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28550527

RESUMO

Yeasts were isolated from three vineyards located in the South Region of Brazil. A cross evaluation was carried out at the oldest vineyard of the study in Pinheiro Preto. Samples of grape berries, grapevine leaves and the soil, along with samples of the winery equipment and effluent, were collected. In the Serra do Marari and Campos Novos vineyards only samples of grape clusters were obtained. The 106 yeast isolates were identified by sequencing the D1/D2 domain of LSU rDNA or ITS1-5.8S-ITS2 region in 22 species. The values for the richness indices varied between the vineyards. A comparison of the taxonomic diversity of the yeasts from these regions using the reciprocal Simpson index showed a significant difference between the Serra do Marari and Campos Novos vineyards (5.72 ± 0.36 and 2.92 ± 0.36, respectively, p < 0.0001). The functional diversity was assessed in relation to the use of carbon and nitrogen sources by the yeasts isolated from each location. In general, we observed that the Pinheiro Preto and Campos Novos vineyards differed consistently from the Serra do Marari vineyard according to these indices (FAD2, FDc and Rao, p < 0.0001). The possible spreading of Saccharomyces cerevisiae from the winery to the vineyard in Pinheiro Preto was observed.


Assuntos
Microbiologia Ambiental , Fazendas , Microbiologia do Solo , Leveduras/classificação , Leveduras/isolamento & purificação , Biodiversidade , Brasil , Carbono/metabolismo , DNA Fúngico/genética , DNA Ribossômico/genética , Filogenia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/isolamento & purificação , Solo , Especificidade da Espécie , Leveduras/genética , Leveduras/crescimento & desenvolvimento
4.
Rev. bras. plantas med ; 18(1,supl.1): 316-325, 2016. tab, graf
Artigo em Português | LILACS | ID: lil-782990

RESUMO

RESUMO A espécie Mikania glomerata Sprengel, popularmente conhecida no Brasil como guaco, é amplamente utilizada como expectorante para tratar doenças respiratórias e tem a sua atividade farmacológica atribuída principalmente a cumarina. Os resultados mostraram que o método apresenta linearidade de 0,05 a 0,8 mg mL-1. Ele foi considerado seletivo, exato e preciso. A proposta de um método rápido para determinação de cumarina em extratos de guaco torna-se interessante para a rotina de controle de qualidade industrial, visando à obtenção de medicamentos fitoterápicos padronizados.


ABSTRACT The species Mikania glomerata Sprengel, popularly known in Brazil as “guaco”, is widely used as an expectorant to treat respiratory diseases. Its pharmacological activity is mainly attributed to coumarin. The results showed that the method for determining coumarin presented linearity from 0.05 to 0.8 mg mL-1. It was considered selective, accurate, and precise according to the specific resolution from ANVISA, the Brazilian regulatory agency. The proposal of a rapid method for the determining coumarin in extracts of guaco is interesting for routine industrial quality control in order to obtain standardized, efficient, and safe phytotherapic medicines.


Assuntos
Espectrometria de Massas/métodos , Cumarínicos/análise , Estudo de Validação , Mikania/classificação , Plantas Medicinais , Fitoterapia
5.
Neuroimage ; 114: 287-93, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25862262

RESUMO

At present, functional magnetic resonance imaging (fMRI) is one of the most useful methods of studying cognitive processes in the human brain in vivo, both for basic science and clinical goals. Although neuroscience studies often rely on group analysis, clinical applications must investigate single subjects (patients) only. Particularly for the latter, issues regarding the reliability of fMRI readings remain to be resolved. To determine the ability of intra-run variability (IRV) weighting to consistently detect active voxels, we first acquired fMRI data from a sample of healthy subjects, each of whom performed 4 runs (4 blocks each) of self-paced finger-tapping. Each subject's data was analyzed using single-run general linear model (GLM), and each block was then analyzed separately to calculate the IRV weighting. Results show that integrating IRV information into standard single-subject GLM activation maps significantly improved the reliability (p=0.007) of the single-subject fMRI data. This suggests that taking IRV into account can help identify the most constant and relevant neuronal activity at the single-subject level.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Dedos , Humanos , Masculino , Atividade Motora , Reprodutibilidade dos Testes , Adulto Jovem
6.
Rev Sci Instrum ; 82(9): 091301, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21974566

RESUMO

The Atacama pathfinder experiment Sunyaev-Zel'dovich (APEX-SZ) instrument is a millimeter-wave cryogenic receiver designed to observe galaxy clusters via the Sunyaev-Zel'dovich effect from the 12 m APEX telescope on the Atacama plateau in Chile. The receiver contains a focal plane of 280 superconducting transition-edge sensor (TES) bolometers instrumented with a frequency-domain multiplexed readout system. The bolometers are cooled to 280 mK via a three-stage helium sorption refrigerator and a mechanical pulse-tube cooler. Three warm mirrors, two 4 K lenses, and a horn array couple the TES bolometers to the telescope. APEX-SZ observes in a single frequency band at 150 GHz with 1' angular resolution and a 22' field-of-view, all well suited for cluster mapping. The APEX-SZ receiver has played a key role in the introduction of several new technologies including TES bolometers, the frequency-domain multiplexed readout, and the use of a pulse-tube cooler with bolometers. As a result of these new technologies, the instrument has a higher instantaneous sensitivity and covers a larger field-of-view than earlier generations of Sunyaev-Zel'dovich instruments. The TES bolometers have a median sensitivity of 890 µK(CMB)√s (NEy of 3.5 × 10(-4) √s). We have also demonstrated upgraded detectors with improved sensitivity of 530 µK(CMB)√s (NEy of 2.2 × 10(-4) √s). Since its commissioning in April 2007, APEX-SZ has been used to map 48 clusters. We describe the design of the receiver and its performance when installed on the APEX telescope.

7.
Science ; 330(6005): 800-4, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-21051633

RESUMO

Gravitational lensing is a powerful astrophysical and cosmological probe and is particularly valuable at submillimeter wavelengths for the study of the statistical and individual properties of dusty star-forming galaxies. However, the identification of gravitational lenses is often time-intensive, involving the sifting of large volumes of imaging or spectroscopic data to find few candidates. We used early data from the Herschel Astrophysical Terahertz Large Area Survey to demonstrate that wide-area submillimeter surveys can simply and easily detect strong gravitational lensing events, with close to 100% efficiency.

8.
Nature ; 439(7076): 563-4, 2006 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-16452973

RESUMO

The most distant known object in the Solar System, 2003 UB313 (97 au from the Sun), was recently discovered near its aphelion. Its high eccentricity and inclination to the ecliptic plane, along with its perihelion near the orbit of Neptune, identify it as a member of the 'scattered disk'. This disk of bodies probably originates in the Kuiper belt objects, which orbit near the ecliptic plane in circular orbits between 30 and 50 au, and may include Pluto as a member. The optical brightness of 2003 UB313, if adjusted to Pluto's distance, is greater than that of Pluto, which suggested that it might be larger than Pluto. The actual size, however, could not be determined from the optical measurements because the surface reflectivity (albedo) was unknown. Here we report observations of the thermal emission of 2003 UB313 at a wavelength of 1.2 mm, which in combination with the measured optical brightness leads to a diameter of 3,000 +/- 300 +/- 100 km. Here the first error reflects measurement uncertainties, while the second derives from the unknown object orientation. This makes 2003 UB313 the largest known trans-neptunian object, even larger than Pluto (2,300 km). The albedo is 0.60 +/- 0.10 +/- 0.05, which is strikingly similar to that of Pluto, suggesting that the methane seen in the optical spectrum causes a highly reflective icy surface.

9.
Nature ; 434(7037): 1112-5, 2005 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-15858569

RESUMO

It was established over a decade ago that the remarkable high-energy transients known as soft gamma-ray repeaters (SGRs) are located in our Galaxy and originate from neutron stars with intense (< or = 10(15)G) magnetic fields-so-called 'magnetars'. On 27 December 2004, a giant flare with a fluence exceeding 0.3 erg cm(-2) was detected from SGR 1806-20. Here we report the detection of a fading radio counterpart to this event. We began a monitoring programme from 0.2 to 250 GHz and obtained a high-resolution 21-cm radio spectrum that traces the intervening interstellar neutral hydrogen clouds. Analysis of the spectrum yields the first direct distance measurement of SGR 1806-20: the source is located at a distance greater than 6.4 kpc and we argue that it is nearer than 9.8 kpc. If correct, our distance estimate lowers the total energy of the explosion and relaxes the demands on theoretical models. The energetics and the rapid decay of the radio source are not compatible with the afterglow model that is usually invoked for gamma-ray bursts. Instead, we suggest that the rapidly decaying radio emission arises from the debris ejected during the explosion.

10.
Science ; 300(5620): 773-5, 2003 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-12677071

RESUMO

Images of the molecular CO 2-1 line emission and the radio continuum emission from the redshift 4.12 gravitationally lensed quasi-stellar object (QSO) PSS J2322+1944 reveal an Einstein ring with a diameter of 1.5". These observations are modeled as a star-forming disk surrounding the QSO nucleus with a radius of 2 kiloparsecs. The implied massive star formation rate is 900 solar masses per year. At this rate, a substantial fraction of the stars in a large elliptical galaxy could form on a dynamical time scale of 108 years. The observation of active star formation in the host galaxy of a high-redshift QSO supports the hypothesis of coeval formation of supermassive black holes and stars in spheroidal galaxies.

11.
Homo ; 52(3): 233-9, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12018119

RESUMO

The description of several teeth and a fragment of mandible found in the Visogliano rock-shelter (Northern Italy) is presented in this paper. The teeth have been analysed from a morphological and metrical point of view and compared with other specimens of Homo erectus, archaic Homo sapiens and Homo neanderthalensis. The MD and BL diameters and the peculiar dental features are archaic and support the antiquity of the specimens. Microwear analysis of Visogliano teeth show various dietary strategies adopted by the individuals of the same site.


Assuntos
Fósseis , Hominidae , Mandíbula/anatomia & histologia , Dente/anatomia & histologia , Animais , Antropologia Física , Dieta , Humanos , Itália
12.
Astrophys J ; 533(1): L13-L16, 2000 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-10727380

RESUMO

We present detections of emission at 250 GHz (1.2 mm) from two high-redshift QSOs from the Sloan Digital Sky Survey sample using the bolometer array at the IRAM 30 m telescope. The sources are SDSSp 015048.83+004126.2 at z=3.7 and SDSSp J033829.31+002156.3 at z=5.0; the latter is the third highest redshift QSO known and the highest redshift millimeter-emitting source yet identified. We also present deep radio continuum imaging of these two sources at 1.4 GHz using the Very Large Array. The combination of centimeter and millimeter observations indicate that the 250 GHz emission is most likely thermal dust emission, with implied dust masses approximately 108 M middle dot in circle. We consider possible dust heating mechanisms, including UV emission from the active galactic nucleus (AGN) and a massive starburst concurrent with the AGN, with implied star formation rates greater than 103 M middle dot in circle yr-1.

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