RESUMEN
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.
RESUMEN
Stellar archaeology shows that massive elliptical galaxies formed rapidly about ten billion years ago with star-formation rates of above several hundred solar masses per year. Their progenitors are probably the submillimetre bright galaxies at redshifts z greater than 2. Although the mean molecular gas mass (5 × 10(10) solar masses) of the submillimetre bright galaxies can explain the formation of typical elliptical galaxies, it is inadequate to form elliptical galaxies that already have stellar masses above 2 × 10(11) solar masses at z ≈ 2. Here we report multi-wavelength high-resolution observations of a rare merger of two massive submillimetre bright galaxies at z = 2.3. The system is seen to be forming stars at a rate of 2,000 solar masses per year. The star-formation efficiency is an order of magnitude greater than that of normal galaxies, so the gas reservoir will be exhausted and star formation will be quenched in only around 200 million years. At a projected separation of 19 kiloparsecs, the two massive starbursts are about to merge and form a passive elliptical galaxy with a stellar mass of about 4 × 10(11) solar masses. We conclude that gas-rich major galaxy mergers with intense star formation can form the most massive elliptical galaxies by z ≈ 1.5.
RESUMEN
In the past decade, our understanding of galaxy evolution has been revolutionized by the discovery that luminous, dusty starburst galaxies were 1,000 times more abundant in the early Universe than at present. It has, however, been difficult to measure the complete redshift distribution of these objects, especially at the highest redshifts (z > 4). Here we report a redshift survey at a wavelength of three millimetres, targeting carbon monoxide line emission from the star-forming molecular gas in the direction of extraordinarily bright millimetre-wave-selected sources. High-resolution imaging demonstrates that these sources are strongly gravitationally lensed by foreground galaxies. We detect spectral lines in 23 out of 26 sources and multiple lines in 12 of those 23 sources, from which we obtain robust, unambiguous redshifts. At least 10 of the sources are found to lie at z > 4, indicating that the fraction of dusty starburst galaxies at high redshifts is greater than previously thought. Models of lens geometries in the sample indicate that the background objects are ultra-luminous infrared galaxies, powered by extreme bursts of star formation.
RESUMEN
Massive present-day early-type (elliptical and lenticular) galaxies probably gained the bulk of their stellar mass and heavy elements through intense, dust-enshrouded starbursts--that is, increased rates of star formation--in the most massive dark-matter haloes at early epochs. However, it remains unknown how soon after the Big Bang massive starburst progenitors exist. The measured redshift (z) distribution of dusty, massive starbursts has long been suspected to be biased low in z owing to selection effects, as confirmed by recent findings of systems with redshifts as high as ~5 (refs 2-4). Here we report the identification of a massive starburst galaxy at z = 6.34 through a submillimetre colour-selection technique. We unambiguously determined the redshift from a suite of molecular and atomic fine-structure cooling lines. These measurements reveal a hundred billion solar masses of highly excited, chemically evolved interstellar medium in this galaxy, which constitutes at least 40 per cent of the baryonic mass. A 'maximum starburst' converts the gas into stars at a rate more than 2,000 times that of the Milky Way, a rate among the highest observed at any epoch. Despite the overall downturn in cosmic star formation towards the highest redshifts, it seems that environments mature enough to form the most massive, intense starbursts existed at least as early as 880 million years after the Big Bang.
RESUMEN
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.
RESUMEN
The old, red stars that constitute the bulges of galaxies, and the massive black holes at their centres, are the relics of a period in cosmic history when galaxies formed stars at remarkable rates and active galactic nuclei (AGN) shone brightly as a result of accretion onto black holes. It is widely suspected, but unproved, that the tight correlation between the mass of the black hole and the mass of the stellar bulge results from the AGN quenching the surrounding star formation as it approaches its peak luminosity. X-rays trace emission from AGN unambiguously, whereas powerful star-forming galaxies are usually dust-obscured and are brightest at infrared and submillimetre wavelengths. Here we report submillimetre and X-ray observations that show that rapid star formation was common in the host galaxies of AGN when the Universe was 2-6 billion years old, but that the most vigorous star formation is not observed around black holes above an X-ray luminosity of 10(44) ergs per second. This suppression of star formation in the host galaxy of a powerful AGN is a key prediction of models in which the AGN drives an outflow, expelling the interstellar medium of its host and transforming the galaxy's properties in a brief period of cosmic time.
RESUMEN
PURPOSE: The restoration of the labrum complex and the influence on secondary osteoarthritis after arthroscopic Bankart repair on magnetic resonance imaging (MRI) remain unclear. METHODS: Twenty-one patients were retrospectively followed after unilateral primary arthroscopic Bankart repair with knot-tying suture anchors (8.8 ± 2.5 years after surgery, age 25.3 ± 6.3 years). Bilateral structural MRI was performed to assess labrum-glenoid restoration by measurements of the labrum slope angle, height index, and labrum interior morphology according to the Randelli classification. Osteoarthritic status was bilaterally assessed by a modified assessment based on the Samilson-Prieto classification. RESULTS: MRI assessment revealed full labrum-glenoid complex restoration with equivalent parameters for anterior slope angle (mean ± SD: 21.3° ± 2.6° after Bankart repair vs. 21.9° ± 2.6° control) and height index (2.34 ± 0.4 vs. 2.44 ± 0.4), as well as the inferior slope angle (23.1° ± 2.9° vs. 23.3° ± 2.1°) and height index (2.21 ± 0.3 vs. 2.21 ± 0.3) (all n.s.). The labrum morphology showed only for the anterior labrum significant alterations (1.4 ± 0.9 vs. 0.6 ± 0.7, p < 0.05), the inferior labrum occurred similarly (1.3 ± 0.8 vs. 0.8 ± 0.5, n.s.). Osteoarthritic changes were significantly increased after Bankart repair compared to the uninjured shoulder (4.8 ± 5.1 mm vs. 2.5 ± 1.0 mm; p < 0.05), with a significant correlation of osteoarthritis status between both shoulders (p < 0.05). Scores generally decreased after Bankart repair (constant 84.6 ± 9.5 vs. 94.5 ± 4.9 control, p < 0.05; Rowe 84.5 ± 6.5 vs. 96.2 ± 4.2, p < 0.05; Walch-Duplay 82.4 ± 7.0 vs. 94.3 ± 4.0, p < 0.05) with a strong correlation with osteoarthritis status (p < 0.05). CONCLUSIONS: Arthroscopic Bankart repair enabled good clinical outcomes and complete quantitative labrum restoration parameters. Next to several well-known parameters, secondary osteoarthritis after arthroscopic Bankart repair significantly correlated with osteoarthritic status of the uninjured contralateral shoulder but was not influenced by quantitative labrum restoration. The recommendation for arthroscopic Bankart repair should be based on clinical parameters and not on prevention of secondary osteoarthritis. STUDY DESIGN: Case series. LEVEL OF EVIDENCE: IV.
Asunto(s)
Osteoartritis/etiología , Luxación del Hombro/cirugía , Articulación del Hombro/cirugía , Anclas para Sutura , Adolescente , Adulto , Artroplastia/métodos , Artroscopía/métodos , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteoartritis/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
BACKGROUND: Morbidity differences between older members of private and statutory health insurance Germany have rarely been examined. Thus, we aimed at determining these differences in old age. METHODS: This study used data from 2 follow-up waves with a 3-year interval from a population-based prospective cohort study (ESTHER study) in Saarland, Germany. Morbidity was assessed by participants' GPs using a generic instrument (Cumulative Illness Rating Scale for Geriatrics). The between estimator was used which exclusively quantifies inter-individual variation. Adjusting for sex and age, we investigated the association between health insurance and morbidity in the main model. In additional models, we adjusted incrementally for the effect of education, family status and income. RESULTS: Regression models not adjusting for income showed that members of private health insurance had a lower morbidity score than members of statutory health insurance. This effect is considerably lower in models adjusting for income, but remained statistically significant (except for men). CONCLUSION: Observed differences in morbidity between older members of private and statutory health insurance can partly be explained by income differences. Thus, our findings highlight the role of model specification in determining the relation between morbidity and health insurance.
Asunto(s)
Renta , Seguro de Salud , Femenino , Alemania , Humanos , Cobertura del Seguro , Masculino , Morbilidad , Estudios ProspectivosRESUMEN
The extragalactic background light at far-infrared wavelengths comes from optically faint, dusty, star-forming galaxies in the Universe with star formation rates of a few hundred solar masses per year. These faint, submillimetre galaxies are challenging to study individually because of the relatively poor spatial resolution of far-infrared telescopes. Instead, their average properties can be studied using statistics such as the angular power spectrum of the background intensity variations. A previous attempt at measuring this power spectrum resulted in the suggestion that the clustering amplitude is below the level computed with a simple ansatz based on a halo model. Here we report excess clustering over the linear prediction at arcminute angular scales in the power spectrum of brightness fluctuations at 250, 350 and 500 µm. From this excess, we find that submillimetre galaxies are located in dark matter haloes with a minimum mass, M(min), such that log(10)[M(min)/M(â)] = 11.5(+0.7)(-0.2) at 350 µm, where M(â) is the solar mass. This minimum dark matter halo mass corresponds to the most efficient mass scale for star formation in the Universe, and is lower than that predicted by semi-analytical models for galaxy formation.
RESUMEN
Background: In Germany, out-of-pocket payments (OOPP) account for a large proportion of total health expenditure. However, there are only few investigations on how morbidity-related, sociodemographic and lifestyle factors affect OOPP particularly in the older population. The aim of this study was to identify factors affecting OOPP for health care services among elderly Germans in a longitudinal setting. Methods: This longitudinal study used data from 2 follow-up waves (3-year interval) from a population-based prospective cohort study (ESTHER study) collected in Saarland, Germany. At the first follow-up wave, subjects were between 57 and 84 years old. Participants provided comprehensive data including individual OOPP for the preceding 3 months. Fixed effects (FE) regressions were used to determine factors affecting OOPP. Results: Mean individual OOPP (3-month period) rose from 119 (first wave) to 136 (second wave). Longitudinal regressions showed that higher morbidity did not affect OOPP. Moreover, changes in sociodemographic as well as lifestyle factors were not related to changes in OOPP. Solely, exemption of OOPP reduced the dependent variable significantly. Conclusion: In contrast to cross-sectional findings for Germany, OOPP are not related to morbidity and income in this study. This underlines the complex nature of OOPP in old age and the need for longitudinal studies to gain some insight into the underlying causal factors.
Asunto(s)
Empleo/economía , Honorarios y Precios/estadística & datos numéricos , Gastos en Salud/estadística & datos numéricos , Renta/estadística & datos numéricos , Estilo de Vida , Programas Nacionales de Salud/economía , Anciano , Anciano de 80 o más Años , Escolaridad , Empleo/estadística & datos numéricos , Femenino , Alemania/epidemiología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Programas Nacionales de Salud/estadística & datos numéricos , Factores SocioeconómicosRESUMEN
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.
RESUMEN
We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg^{2} patch of sky centered on RA 0 h, Dec. -57.5°. The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2 µK deg in Q and U at 143 GHz). We detect 150×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150 GHz to a lensed-ΛCDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r_{0.05}<0.12 at 95% confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0σ significance.
RESUMEN
PURPOSE: Due to demographic aging, economic evaluation of health care technologies for the elderly becomes more important. A standardised questionnaire to measure the health-related resource utilisation has been designed. The monetary valuation of the resource use documented by the questionnaire is a central step towards the determination of the corresponding costs. The aim of this paper is to provide unit costs for the resources in the questionnaire from a societal perspective. METHODS: The unit costs are calculated pragmatically based on regularly published sources. Thus, an easy update is possible. RESULTS: This paper presents the calculated unit costs for outpatient medical care, inpatient care, informal and formal nursing care and pharmaceuticals from a societal perspective. CONCLUSION: The calculated unit costs can serve as a reference case in health economic evaluations and hence help to increase their comparability.
Asunto(s)
Costos y Análisis de Costo/normas , Atención a la Salud/economía , Costos de la Atención en Salud/estadística & datos numéricos , Costos de la Atención en Salud/normas , Servicios de Salud para Ancianos/economía , Servicios de Salud/economía , Costos y Análisis de Costo/economía , Alemania , Servicios de Salud/estadística & datos numéricos , Servicios de Salud para Ancianos/normas , Modelos Económicos , Valores de Referencia , Revisión de Utilización de Recursos/economía , Revisión de Utilización de Recursos/normasRESUMEN
AIM: Due to demographic trends towards an ageing population resource use of health care will increase. By collecting health-related costs via questionnaires, the impact of socio-economic variables and other medical factors can be examined. In addition, only patient reported resource use accounts for out-of-pocket payments. Thus, it is necessary to develop an appropriate tool to collect the health-related resource use in an elderly population. METHODS: The development of the FIMA (questionnaire for the use of medical and non-medical services in old age) was carried out in 6 steps. These included the determination of necessary questionnaire contents based on a literature review and the wording and layout were defined. Finally the questionnaire was tested in a pilot study and was modified. RESULTS: All direct medical and non-medical resource use excluding transportation and time costs were recorded. Productivity losses were not included. The recall time frames differed according to resource categories (7 days, 3 months, 12 months). For the pilot study, 63 questionnaires were analysed. The response rate was 69%. The questionnaire took an average of 21 min to complete. Three quarters of respondents completed the questionnaire without help and 90% rated the difficulty as easy or even very simple. There was good agreement between self-reported health-related quality of life and the resource use of nursing and domestic help (phi coefficient values between 0.52 and 0.58). CONCLUSION: The FIMA is a generic questionnaire which collects the health-related resource use within the older population groups.
Asunto(s)
Gastos en Salud/estadística & datos numéricos , Servicios de Salud para Ancianos/economía , Servicios de Salud para Ancianos/estadística & datos numéricos , Encuestas y Cuestionarios , Revisión de Utilización de Recursos/economía , Revisión de Utilización de Recursos/métodos , Anciano , Anciano de 80 o más Años , Femenino , Alemania , Humanos , Masculino , Proyectos Piloto , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
PURPOSE: Changes in aortic geometry or presence of aortic valve (AoV) disease can result in substantially altered aortic hemodynamics. Dilatation of the ascending aorta or AoV abnormalities can result in an increase in helical flow. METHODS: 4D flow magnetic resonance imaging was used to test the feasibility of quantitative helicity analysis using equidistantly distributed 2D planes along the entire aorta. The evaluation of the method included three parts: (1) the quantification of helicity in 12 healthy subjects, (2) an evaluation of observer variability and test-retest reliability, and (3) the quantification of helical flow in 16 patients with congenitally altered bicuspid AoVs. RESULTS: Helicity quantification in healthy subjects revealed consistent directions of flow rotation along the entire aorta with high clockwise helicity in the aortic arch and an opposite rotation sense in the ascending and descending aorta. The results demonstrated good scan-rescan and inter- and intraobserver agreement of the helicity parameters. Helicity quantification in patients revealed a significant increase in absolute peak relative helicity during systole and a considerably greater heterogeneous distribution of mean helicity in the aorta. CONCLUSION: The method has the potential to serve as a reference distribution for comparisons of helical flow between healthy subjects and patients or between different patient groups.
Asunto(s)
Aorta/patología , Aorta/fisiopatología , Válvula Aórtica/anomalías , Enfermedades de las Válvulas Cardíacas/patología , Enfermedades de las Válvulas Cardíacas/fisiopatología , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Angiografía por Resonancia Magnética/métodos , Adulto , Válvula Aórtica/patología , Válvula Aórtica/fisiopatología , Enfermedad de la Válvula Aórtica Bicúspide , Velocidad del Flujo Sanguíneo , Técnicas de Imagen Sincronizada Cardíacas/métodos , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
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 ââ¼80. 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)âs. 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 < â < 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 â¼(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.
RESUMEN
Gravitational lensing of the cosmic microwave background generates a curl pattern in the observed polarization. This "B-mode" signal provides a measure of the projected mass distribution over the entire observable Universe and also acts as a contaminant for the measurement of primordial gravity-wave signals. In this Letter we present the first detection of gravitational lensing B modes, using first-season data from the polarization-sensitive receiver on the South Pole Telescope (SPTpol). We construct a template for the lensing B-mode signal by combining E-mode polarization measured by SPTpol with estimates of the lensing potential from a Herschel-SPIRE map of the cosmic infrared background. We compare this template to the B modes measured directly by SPTpol, finding a nonzero correlation at 7.7σ significance. The correlation has an amplitude and scale dependence consistent with theoretical expectations, is robust with respect to analysis choices, and constitutes the first measurement of a powerful cosmological observable.
RESUMEN
The aim of this study was to evaluate the performance of a closed circuit MR compatible pneumatically driven pump system using a ventricular assist device as pulsatile flow pump for in vitro 3D flow simulation. Additionally, a pressure control unit was integrated into the flow circuit. The performance of the pump system and its test-retest reliability was evaluated using a stenosis phantom (60% lumen narrowing). Bland-Altman analysis revealed a good test-retest reliability (mean differences = -0.016 m/s, limits of agreement = ±0.047 m/s) for in vitro flow measurements. Furthermore, a rapid prototyping in vitro model of a normal thoracic aorta was integrated into the flow circuit for a direct comparison of flow characteristics with in vivo data in the same subject. The pneumatically driven ventricular assist device was attached to the ascending aorta of the in vitro model to simulate the beating left ventricle. In the descending part of the healthy aorta a flexible stenosis was integrated to model an aortic coarctation. In vivo and in vitro comparison showed significant (P = 0.002) correlations (r = 0.9) of mean velocities. The simulation of increasing coarctation grade led to expected changes in the flow patterns such as jet flow in the post-stenotic region and increased velocities.
Asunto(s)
Determinación de la Presión Sanguínea/instrumentación , Corazón Auxiliar , Imagen por Resonancia Magnética/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , RetroalimentaciónRESUMEN
BACKGROUND AND AIMS: There is increasing evidence that suppressed bud burst and thus epicormic shoot emergence (sprouting) are controlled by water-carbohydrate supplies to entire trees and buds. This direct evidence is still lacking for oak. In other respects, recent studies focused on sessile oak, Quercus petraea, have confirmed the important constraints of sprouting by epicormic ontogeny. The main objective of this paper was thus to provide provisional confirmation of the water-carbohydrate control and direct evidence of the ontogenic constraints by bringing together results already published in separate studies on water status and distribution of carbohydrates, and on accompanying vegetation and epicormics, which also quantify epicormic ontogeny. METHODS: This paper analyses results gained from a sessile oak experiment in which part of the site was free from fairly tall, dense accompanying vegetation. This experiment was initially focused on stand water status and more recently on the carbohydrate distribution of dominant trees. External observations of the epicormic composition and internal observations with X-ray computer tomography were undertaken on 60 and six trees, respectively. KEY RESULTS: Sprouting was more intense in the part of the stand free from accompanying vegetation and on upper trunk segments. A clear effect of epicormic ontogeny was demonstrated as well: the more epicormics a trunk segment bears, the more chances it had to bear sprouts. CONCLUSIONS: These results indirectly infer water-carbohydrate control and show direct evidence of constraints by epicormic ontogeny. These results have far-reaching consequences related to the quantification of all functions fulfilled by any type of epicormic structure in any part of the tree.
Asunto(s)
Quercus/crecimiento & desarrollo , Quercus/metabolismo , Agua/metabolismo , Transporte Biológico , Metabolismo de los Hidratos de Carbono , Francia , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/metabolismoRESUMEN
In the food industry, most fatty acid-rich oils are primarily composed of saturated even-chain fatty acids. However, saturated odd-chain fatty acids are potentially a beneficial alternative to other saturated fatty acid-containing oils. In this communication, we examine the safety of odd-chain fatty acid (OCFA) algal oil, a microalgal-sourced oil composed primarily of the saturated odd-chain fatty acids pentadecanoic acid and heptadecanoic acid. OCFA algal oil was assessed for toxicity in a 14-day palatability study and comprehensive 13-week dietary study at inclusion levels of 5%, 10%, and 15% in the diet, utilizing a DHA-rich algal oil as a comparator control. No adverse effects attributed to the consumption of OCFA algal oil were observed in either study. Therefore, we report a No Observable Adverse Effect Level (NOAEL) of 150,000 ppm (15% in the diet), equivalent to an OCFA algal oil intake of 7553.9 and 8387.7 mg/kg bw/day for male and female rats, respectively. The genotoxic potential of OCFA algal oil was also examined in an in vitro bacterial reverse mutation assay and in vivo mammalian bone marrow chromosome aberration test. OCFA algal oil was non-mutagenic in Salmonella typhimurium and Escherichia coli test strains and did not exhibit clastogenicity in vivo.