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1.
Science ; 379(6634): eabn8671, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36137011

RESUMEN

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

2.
J Hum Nutr Diet ; 31(3): 337-348, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29543356

RESUMEN

BACKGROUND: A tailored approach to nutrition and physical activity advice can support women following childbirth in managing barriers (i.e. time and childcare) to making healthy lifestyle changes. The aim of the present study was to evaluate the implementation, acceptability and preliminary efficacy of a personally tailored nutrition and exercise programme for postpartum women delivered via video-consultations by an accredited practising dietitian (APD) and accredited exercise physiologist (AEP). METHODS: In this feasibility study (VITAL change for mums), postpartum (3-12 months) women (body mass index ≥25 or >2 kg above pre-pregnancy weight) who were seeking to achieve a healthy weight participated in a single-arm intervention. Participants received up to five real-time personalised video-consultations (2 × APD, 2 × AEP, 1 × either) over the 8-week intervention period. Implementation (recruitment, retention, utilisation), acceptability (participant satisfaction) and preliminary efficacy (anthropometry, dietary intake, cardiovascular fitness, physical activity level, psychological wellbeing) were assessed. RESULTS: Thirty women [mean (SD) age 31.6 (3.1) years, body mass index 29.0 (4.0) kg m-2 , 100% married/de facto, 80% university level education] were recruited within 10 days and 27 completed the study. Women's mean (SD) ratings (out of a score of 5) indicated satisfaction with the video-consultations [4.4 (0.9)] and the online setting [4.5 (0.8)]. Women agreed that accessing an APD [4.4 (0.8)] and AEP [4.3 (0.9)] was easier using video-consultations than attending an in-person consultation. Statistically significant improvements in waist circumference, body composition, cardiorespiratory fitness, dietary intake and physical activity were observed from baseline to 8 weeks. CONCLUSIONS: The findings of the present study suggest that a nutrition and exercise intervention delivered by qualified health professionals via video-consultations is feasible, acceptable and achieves positive outcomes for women following childbirth.


Asunto(s)
Dietoterapia/métodos , Dietética/métodos , Terapia por Ejercicio/métodos , Periodo Posparto , Consulta Remota/métodos , Adulto , Índice de Masa Corporal , Dietoterapia/psicología , Terapia por Ejercicio/psicología , Estudios de Factibilidad , Femenino , Implementación de Plan de Salud , Estilo de Vida Saludable , Humanos , Nueva Gales del Sur , Aceptación de la Atención de Salud , Embarazo , Resultado del Tratamiento , Grabación de Cinta de Video
3.
Dalton Trans ; 46(18): 5781-5785, 2017 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-28401979

RESUMEN

Here, the excellent thermal sensing capability of a multinuclear lanthanide polyoxometalate in the cryogenic region (<100 K) is presented for the first time. Up till now, no lanthanide polyoxometalates have been studied for their use as ratiometric luminescent thermometers. The investigated Tb3+ polyoxometalate cluster is doped with 1.6% (P1) and 8.4% (P2) of Eu3+ ions. When excited into the Mo-O charge transfer bands, at room temperature only the emission of the Eu3+ ions is observed suggesting a very efficient energy transfer between Mo-O→Tb3+→Eu3+. Only in the cryogenic region the emission of Tb3+ is also witnessed.

4.
Metallomics ; 7(6): 996-1010, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25832493

RESUMEN

Every infection is a battle for trace elements. Neutrophils migrate first to the infection site and accumulate quickly to high numbers. They fight pathogens by phagocytosis and intracellular toxication. Additionally, neutrophils form neutrophil extracellular traps (NETs) to inhibit extracellular microbes. Yet, neutrophil trace element characteristics are largely unexplored. We investigated unstimulated and phorbol myristate acetate-stimulated neutrophils using synchrotron radiation X-ray fluorescence (SR-XRF) on the sub-micron spatial resolution level. PMA activates pinocytosis, cytoskeletal rearrangements and the release of NETs, all mechanisms deployed by neutrophils to combat infection. By analyzing Zn, Fe, Cu, Mn, P, S, and Ca, not only the nucleus but also vesicular granules were identifiable in the elemental maps. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) revealed a neutrophil-specific composition of Zn, Fe, Cu, and Mn in comparison with J774 and HeLa cells, indicating a neutrophil-specific metallome complying with their designated functions. When investigating PMA-activated neutrophils, the SR-XRF analysis depicted typical subcellular morphological changes: the transformation of nucleus and granules and the emergence of void vacuoles. Mature NETs were evenly composed of Fe, P, S, and Ca with occasional hot spots containing Zn, Fe, and Ca. An ICP-MS-based quantification of NET supernatants revealed a NETosis-induced decrease of soluble Zn, whereas Fe, Cu, and Mn concentrations were only slightly affected. In summary, we present a combination of SR-XRF and ICP-MS as a powerful tool to analyze trace elements in human neutrophils. The approach will be applicable and valuable to numerous aspects of nutritional immunity.


Asunto(s)
Activación Neutrófila , Neutrófilos/metabolismo , Oligoelementos/metabolismo , Animales , Disponibilidad Biológica , Núcleo Celular/metabolismo , Células HeLa , Humanos , Metaboloma , Ratones , Espectrometría por Rayos X , Espectrofotometría Atómica
5.
Nature ; 507(7491): 221-4, 2014 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-24622201

RESUMEN

The ultimate origin of water in the Earth's hydrosphere is in the deep Earth--the mantle. Theory and experiments have shown that although the water storage capacity of olivine-dominated shallow mantle is limited, the Earth's transition zone, at depths between 410 and 660 kilometres, could be a major repository for water, owing to the ability of the higher-pressure polymorphs of olivine--wadsleyite and ringwoodite--to host enough water to comprise up to around 2.5 per cent of their weight. A hydrous transition zone may have a key role in terrestrial magmatism and plate tectonics, yet despite experimental demonstration of the water-bearing capacity of these phases, geophysical probes such as electrical conductivity have provided conflicting results, and the issue of whether the transition zone contains abundant water remains highly controversial. Here we report X-ray diffraction, Raman and infrared spectroscopic data that provide, to our knowledge, the first evidence for the terrestrial occurrence of any higher-pressure polymorph of olivine: we find ringwoodite included in a diamond from Juína, Brazil. The water-rich nature of this inclusion, indicated by infrared absorption, along with the preservation of the ringwoodite, is direct evidence that, at least locally, the transition zone is hydrous, to about 1 weight per cent. The finding also indicates that some kimberlites must have their primary sources in this deep mantle region.

7.
Anal Bioanal Chem ; 405(18): 6061-8, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23681201

RESUMEN

The unique potential of nanoscale elemental imaging of major/minor and trace-level elemental distributions within thin biological tissue sections of the ecotoxicological model organism Daphnia magna is demonstrated by synchrotron radiation nano-X-ray fluorescence (nano-XRF). The applied highly specialized sample preparation method, coupled with the high spatial resolution (∼180 nm) and high X-ray photon flux (6 × 10(11) photons/s) available at the European Synchrotron Radiation Facility (ESRF) ID22NI beamline proved to be critical for the high-quality visualization of (trace-)metal distributions on the submicron level within the target structures of interest. These include the branchial sacs on the thoracic appendages (epipodites) of D. magna, which are osmoregulatory regions where ion exchange occurs. For the main element of interest (Zn), detection limits of 0.7 ppm (3 ag) was reached in fast-scanning mode using an acquisition time of 0.3 s/pixel. As demonstrated, synchrotron radiation nano-XRF revealed the elemental distributions of Ca, Fe, and Zn within this osmoregulatory region on the submicron scale, aiding the exploration of possible detoxification mechanisms of Zn within D. magna at the subtissue level.


Asunto(s)
Daphnia/química , Ecotoxicología/métodos , Metales/farmacocinética , Nanotecnología/instrumentación , Nanotecnología/métodos , Animales , Calcio/análisis , Calcio/farmacocinética , Calibración , Daphnia/anatomía & histología , Daphnia/efectos de los fármacos , Diseño de Equipo , Fluorescencia , Hierro/análisis , Hierro/farmacocinética , Límite de Detección , Metales/análisis , Sincrotrones , Distribución Tisular , Rayos X , Zinc/análisis , Zinc/farmacocinética
8.
Environ Sci Technol ; 46(2): 1178-84, 2012 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-22208159

RESUMEN

Recent studies have suggested that exposure of the freshwater invertebrate Daphnia magna to dietary Zn may selectively affect reproduction without an associated increase of whole body bioaccumulation of Zn. The aim of the current research was therefore to investigate the hypothesis that dietary Zn toxicity is the result of selective accumulation in tissues that are directly involved in reproduction. Since under field conditions simultaneous exposure to both waterborne and dietary Zn is likely to occur, it was also tested if accumulation and toxicity under combined waterborne and dietary Zn exposure is the result of interactive effects. To this purpose, D. magna was exposed during a 16-day reproduction assay to Zn following a 5 × 2 factorial design, comprising five waterborne concentrations (12, 65, 137, 207, and 281 µg Zn/L) and two dietary Zn levels (49.6 and 495.9 µg Zn/g dry wt.). Tissue-specific Zn distribution was quantified by synchrotron radiation based confocal X-ray fluorescence (XRF). It was observed that the occurrence of reproductive inhibition due to increasing waterborne Zn exposure (from 65 µg/L to 281 µg/L) was accompanied by a relative increase of the Zn burdens which was similar in all tissues considered (i.e., the carapax, eggs, thoracic appendages with gills and the cluster comprising gut epithelium, storage cells and ovaries). In contrast, the impairment of reproduction during dietary Zn exposure was accompanied by a clearly discernible Zn accumulation in the eggs only (at 65 µg/L of waterborne Zn). During simultaneous exposure, bioaccumulation and toxicity were the result of interaction, which implies that the tissue-specific bioaccumulation and toxicity following dietary Zn exposure are dependent on the Zn concentration in the water. Our findings emphasize that (i) effects of dietary Zn exposure should preferably not be investigated in isolation from waterborne Zn exposure, and that (ii) XRF enabled us to provide possible links between tissue-specific bioaccumulation and reproductive effects of Zn.


Asunto(s)
Daphnia/efectos de los fármacos , Daphnia/metabolismo , Contaminantes Químicos del Agua/toxicidad , Agua/química , Zinc/toxicidad , Animales , Dieta , Contaminación de Alimentos , Espectrometría por Rayos X , Sincrotrones , Contaminantes Químicos del Agua/química , Zinc/química
9.
Artículo en Inglés | MEDLINE | ID: mdl-21943711

RESUMEN

The Breviary of Arnold of Egmond is one of the most wealthily illuminated fifteenth century manuscripts in the Northern Netherlands. The manuscript originally contained a number of full-page miniatures, which were all removed at an unknown date before 1902. The three remaining miniatures studied here, are today part of different collections, but they were brought together for an exhibition. Although several historical and art historical details of this breviary have extensively been studied, no examination of the materials used was undertaken before. Analytical techniques, such as mobile Raman spectroscopy, can be used to characterise and identify these materials in a non-invasive way. This paper presents the results of the in situ Raman analysis of three full-page miniatures of the Breviary of Arnold of Egmond. During this study, different pigments could be identified, such as lead white (2PbCO(3)·Pb(OH)(2)), lead-tin yellow type I (Pb(2)SnO(4)), ultramarine (Na(8-10)Al(6)Si(6)O(24)S(2-4)), massicot (PbO), vermilion (HgS) and red lead (Pb(3)O(4)). Next to identification of the pigments, visual analysis was used to detect differences and similarities between the stylistic elements of the three analysed folios.


Asunto(s)
Arte/historia , Libros Ilustrados/historia , Colorantes/análisis , Espectrometría Raman/métodos , Historia del Siglo XV , Países Bajos
10.
Artículo en Inglés | MEDLINE | ID: mdl-21530370

RESUMEN

A selection of illuminations of the 12th century manuscript Liber Floridus was analysed with Raman spectroscopy (in situ and laboratory measurements), X-ray fluorescence spectroscopy, UV-fluorescence photography and infrared reflectography (IRR). The aim of this study is to determine the pigments used, in order to search for anachronisms. Using a combination of Raman spectroscopy (molecular information) and X-ray fluorescence spectroscopy (elemental information) following pigments could be identified: ultramarine (Na(8-10)Al(6)Si(6)O(24)S(2-4)), azurite (2CuCO(3)·Cu(OH)(2)), caput mortuum (Fe(2)O(3)), vermilion (HgS), orpiment (As(2)S(3)) and lead white (2PbCO(3)·Pb(OH)(2)). Moreover, two synthetic red pigments, PR4 and PR176, and a degradation product, gypsum (CaSO(4)·2H(2)O), were present in the manuscript. To establish the origin of the modern materials UV-fluorescence photography was used. Infrared reflectography (IRR) was applied to visualise the underdrawing of the investigated folios.


Asunto(s)
Arte/historia , Colorantes/análisis , Colorantes/historia , Manuscritos como Asunto/historia , Fotograbar/métodos , Espectrometría por Rayos X/métodos , Espectrometría Raman/métodos , Color , Historia Medieval
12.
Anal Chem ; 74(5): 1128-35, 2002 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11924974

RESUMEN

A new quantification procedure was developed for the evaluation of X-ray microfluorescence (XRF) data sets obtained from individual particles, based on iterative Monte Carlo (MC) simulation. Combined with the high sensitivity of synchrotron radiation-induced XRF spectroscopy, the method was used to obtain quantitative information down to trace-level concentrations from micrometer-sized particulate matter. The detailed XRF simulation model was validated by comparison of calculated and experimental XRF spectra obtained for glass microsphere standards, resulting in uncertainties in the range of 3-10% for the calculated elemental sensitivities. The simulation model was applied for the quantitative analysis of X-ray tube and synchrotron radiation-induced scanning micro-XRF spectra of individual coal and wood fly ash particles originating from different Hungarian power plants. By measuring the same particles by both methods the major, minor, and trace element compositions of the particles were determined. The uncertainty of the MC based quantitative analysis scheme is estimated to be in the range of 5-30%.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Carbono/análisis , Algoritmos , Ceniza del Carbón , Método de Montecarlo , Material Particulado , Reproducibilidad de los Resultados , Espectrometría por Rayos X
13.
J Pharm Biomed Anal ; 22(2): 349-53, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10719918

RESUMEN

In the manufacturing plants of many pharmaceutical companies the reaction apparatus is suitable to produce different active pharmaceutical ingredients. After completing the production of a compound the equipment should be cleaned in order to avoid the cross contamination in the next lot of the other products. In the authors' laboratory several chromatographic methods were introduced to measure the amount of the residual substances remaining on the surface of the apparatus after the cleaning procedure. A sensitive and fairly rapid overpressured layer chromatographic (OPLC) procedure--suitable to separate and control five steroid hormone compounds (allylestrenol, estradiol, ethynodiol diacetate, levonorgestel, norethisterone) produced in the same equipment at different times--was developed and validated.


Asunto(s)
Cromatografía Liquida/métodos , Hormonas Esteroides Gonadales/análisis , Industria Farmacéutica/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
14.
J AHIMA ; 69(1): 40-2, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10174720

RESUMEN

The possibility of an investigation related to fraud and abuse is the last thing most people want to think about, but it's important to be prepared, just in case. The author gives some advice on how to react if your facility is the target of an investigation and points out some important steps to take to ensure compliance.


Asunto(s)
Fraude/prevención & control , Agencias Gubernamentales , Adhesión a Directriz , Formulario de Reclamación de Seguro/legislación & jurisprudencia , Administradores de Registros Médicos , Regulación y Control de Instalaciones , Fraude/legislación & jurisprudencia , Mal Uso de los Servicios de Salud/legislación & jurisprudencia , Administradores de Registros Médicos/educación , Política Organizacional , Medición de Riesgo , Desarrollo de Personal , Estados Unidos
15.
Orv Hetil ; 135(2): 59-65, 1994 Jan 09.
Artículo en Húngaro | MEDLINE | ID: mdl-8295771

RESUMEN

Out of 700 patients operated on account of myasthenia gravis, 144 cases with tumours (20.57%) were evaluated. Classification took place in five groups: 1. Thymoma and myasthenia gravis; 2. Thymic cysts and myasthenia gravis; 3. Thymoma and latent myasthenia gravis; 4. Paraneoplastic myasthenia-syndrome; 5. Thymoma, myasthenia gravis and myasthenia-syndrome. Up-to-date classification of thymomas is: epithelioma with minimal, marked or overwhelming lymphatic reaction. Dark-cell and light-cell epitheliomas equally associate with myasthenia. Concerning prognosis, location of the tumour to thymic capsula, surrounding, perithymic tissue is more important than the histologic structure of the tumour. Previous examination in the case of mediastinal tumour can reveal latent, mild myasthenia which was not known till that time. Term of postthymectomic myasthenia can be excluded on the basis of these examinations. Heterogeneity is considerable among myasthenia-syndromes concerning both histopathologic and clinical features. There is a double indication of operation in the case of myasthenia with tumour: the tumour and the disease. Good results can be achieved in myasthenia gravis associated with tumour by means of total operation, post-operative radiation and by other up-to-date therapeutical procedures. The results are hardly beyond those of non-tumours myasthenia gravis.


Asunto(s)
Miastenia Gravis/complicaciones , Timoma/complicaciones , Neoplasias del Timo/complicaciones , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome , Timectomía , Timoma/cirugía , Neoplasias del Timo/cirugía
16.
Acta Vet Hung ; 39(1-2): 49-57, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1750365

RESUMEN

Five ram lambs (average body mass: 25 kg) were given, through a catheter inserted into the left ruminal vein, a total of 28.8 mM sodium acetate, 14.4 mM sodium propionate and 4.8 mM sodium butyrate per kg body mass as a 2-hour infusion. During and at 0, 1, 2, 4, 6, 10 and 24 h after the infusion blood samples were taken from the jugular vein and the blood plasma was assayed for free amino acid (FAA) and immunoreactive insulin (IRI) concentrations. Volatile fatty acid (VFA) infusion significantly decreased the blood plasma concentrations of all FAA but cystine. The lowest FAA concentrations were measured in plasma samples taken at the end of the 2-h infusion. Subsequently the level of all amino acids rose and by 24 h after the infusion the blood plasma concentration of all FAA came close to the preinfusion value. The largest differences were observed in the concentration of glutamate, glycine, leucine and isoleucine. In contrast to FAA, IRI concentration was increased significantly (almost fivefold) by VFA infusion. By 10 h after the infusion IRI concentration returned to the initial level. The results reported here indicate that energy supply given in the form of VFA infusion significantly affects blood plasma FAA profiles, supposedly as a result of changes induced in protein synthesis in tissues. Insulin presumably plays a role in the regulation of these changes.


Asunto(s)
Aminoácidos/sangre , Ácidos Grasos Volátiles/administración & dosificación , Ovinos/sangre , Animales , Infusiones Intravenosas/veterinaria , Insulina/sangre , Masculino
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