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1.
Phys Rev Lett ; 123(7): 072701, 2019 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-31491090

RESUMEN

Earth is constantly bombarded with extraterrestrial dust containing invaluable information about extraterrestrial processes, such as structure formation by stellar explosions or nucleosynthesis, which could be traced back by long-lived radionuclides. Here, we report the very first detection of a recent ^{60}Fe influx onto Earth by analyzing 500 kg of snow from Antarctica by accelerator mass spectrometry. By the measurement of the cosmogenically produced radionuclide ^{53}Mn, an atomic ratio of ^{60}Fe/^{53}Mn=0.017 was found, significantly above cosmogenic production. After elimination of possible terrestrial sources, such as global fallout, the excess of ^{60}Fe could only be attributed to interstellar ^{60}Fe which might originate from the solar neighborhood.

2.
J Environ Radioact ; 166(Pt 1): 36-44, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27006171

RESUMEN

After the Fukushima accident, large amounts of radionuclides were discharged to the atmosphere. Some of them travelled long distances and were detected in places as far from Japan as Spain a few days after the accident. One of these radionuclides was 131I. Its isotope 129I (T1/2 = 15.7 × 106 years) was also expected to follow the same pathway. In this work, we present the results for the 129I concentration in the same atmospheric samples from Seville (Spain) where 131I activity was measured in 2011 by Baeza et al. (2012). 129I concentrations in aerosol and gaseous samples showed concentrations in the order of 104 and 105 atoms/m3, typically higher in the gaseous form with respect to the aerosol form. Also 129I in rainwater was measured, showing concentrations in the order of 108 atoms/L. The results show a very good agreement with the 131I profile, showing that, if background from other sources is not relevant, it is possible to estimate the impact of similar events years after them thanks to the sensitivity of techniques like Accelerator Mass Spectrometry.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Contaminación Radiactiva del Aire/estadística & datos numéricos , Accidente Nuclear de Fukushima , Radioisótopos de Yodo/análisis , Monitoreo de Radiación , Atmósfera/química , Espectrometría de Masas , España
3.
Phys Rev Lett ; 116(15): 151104, 2016 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-27127953

RESUMEN

A dying massive star ends in a supernova explosion ejecting a large fraction of its mass into the interstellar medium. If this happens nearby, part of the ejecta might end on Solar System bodies and, in fact, radioactive ^{60}Fe has been detected on the Pacific ocean floor in about 2 Ma old layers. Here, we report on the detection of this isotope also in lunar samples, originating presumably from the same event. The concentration of the cosmic ray produced isotope ^{53}Mn, measured in the same samples, proves the supernova origin of the ^{60}Fe. From the ^{60}Fe concentrations found we deduce a reliable value for the local interstellar fluence in the range of 1×10^{8} at/cm^{2}. Thus, we obtain constraints on the recent and nearby supernova(e).

4.
Mar Pollut Bull ; 89(1-2): 180-190, 2014 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25457809

RESUMEN

Measurements of (129)I carried out on sea ice samples collected in the central Arctic Ocean in 2007 revealed relatively high levels in the range of 100-1400×10(7) at L(-1) that are comparable to levels measured in the surface mixed layer of the ocean at the same time. The (129)I/(127)I ratio in sea ice is much greater than that in the underlying water, indicating that the (129)I inventory in sea ice cannot be supported by direct uptake from seawater or by iodine volatilization from proximal (nearby) oceanic regimes. Instead, it is proposed that most of the (129)I inventory in the sea ice is derived from direct atmospheric transport from European nuclear fuel reprocessing plants at Sellafield and Cap La Hague. This hypothesis is supported by back trajectory simulations indicating that volume elements of air originating in the Sellafield/La Hague regions would have been present at arctic sampling stations coincident with sampling collection.


Asunto(s)
Contaminantes Atmosféricos/análisis , Cubierta de Hielo , Radioisótopos de Yodo/análisis , Regiones Árticas , Atmósfera , Océanos y Mares , Agua de Mar
5.
Arch Esp Urol ; 67(4): 345-9, 2014 May.
Artículo en Inglés, Español | MEDLINE | ID: mdl-24892397

RESUMEN

OBJECTIVE: Congenital anomalies or malformations of the urethra that involve number are extremely rare and only 7 cases of trifurcation of the urethra and under 500 cases of urethral duplication have been described. METHODS: In the case we present, urethral duplication was diagnosed in adulthood, even though glans malformation with 2 urethral orifices was clearly evident and only 1 was functional. RESULTS: The condition is usually diagnosed in childhood due to the presence of 2 urethral meatus or from double stream if both are functional; at other times, the condition is diagnosed from complications that trigger infections or obstruction or if it is associated with more extensive malformations. CONCLUSIONS: Urethral duplication is an extremely rare birth defect, and diagnosis in adulthood is even more uncommon. No single embryologic argument explains all the anatomic variants of urethral duplication. The treatment of the urethral duplication should be individualized according to the type of duplication and the clinical symtoms.


Asunto(s)
Uretra/anomalías , Humanos , Masculino , Persona de Mediana Edad , Trastornos Urinarios/etiología
6.
Chemosphere ; 108: 76-84, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24875915

RESUMEN

(129)I is a very long-lived radionuclide (T1/2=15.7×10(6) years) that is present in the environment because of natural and anthropogenic sources. Compared to the pre-nuclear era, large amounts of (129)I have been released to the marine environment, especially as liquid and gaseous discharges from two European reprocessing facilities located at Sellafield (England) and La Hague (France). The marine environment, i.e., the oceans, is the major source of iodine. Brown seaweed accumulates iodine at high levels up to 1.0% of dry weigh, and therefore they are ideal bioindicators for studying levels of (129)I. In this work, (129)I concentrations have been determined in seaweed Fucus vesiculosus and seawater collected in the Kattegat and Skagerrak areas in July 2007. The resulting data were evaluated in terms of (129)I concentrations and (129)I/(137)Cs ratios. (129)I concentrations were found to be in the order of (44-575)×10(9) atoms g(-1) in seaweed and (5.4-51)×10(9) atoms g(-1) in seawater, with an enhancement in the Skagerrak area in comparison to the Kattegat area. Iodine-129 concentrations in both seaweed and seawater were used to determine the concentration factor of iodine in brown seaweed F. vesiculosus. The high levels of (129)I and (129)I/(137)Cs ratios in the Skagerrak area and their gradually decreasing trend to the Kattegat indicates that the most important contribution to the (129)I inventory in those areas comes from Sellafield and La Hague reprocessing plants.


Asunto(s)
Radioisótopos de Cesio/análisis , Fucus/química , Radioisótopos de Yodo/análisis , Agua de Mar/análisis , Algas Marinas/química , Contaminantes Radiactivos del Agua/análisis , Radioisótopos de Cesio/metabolismo , Monitoreo del Ambiente , Europa (Continente) , Fucus/metabolismo , Radioisótopos de Yodo/metabolismo , Algas Marinas/metabolismo , Contaminantes Radiactivos del Agua/metabolismo
7.
J Environ Radioact ; 115: 134-42, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22939948

RESUMEN

(129)I is a very long-lived radionuclide (T(1/2) = 15.7 × 10(6) years) that is present in the environment both because of natural and anthropogenic sources. In this work (129)I concentration and (129)I/(127)I ratio have been determined in seaweed Fucus vesiculosus collected in the Southern Baltic Sea during 1982 and 1986 (post-Chernobyl accident). The resulting data were evaluated in terms of (129)I concentrations, (129)I/(127)I and (129)I/(137)Cs ratios. (129)I concentrations were found to be in the order of (0.82-5.89) × 10(9) atoms g(-1) in 1982 and (1.33-38.83) × 10(9) atoms g(-1) in 1986. The (129)I/(127)I ratios ranged from (22.7-87.8) × 10(-10) for seaweed collected in 1982 and from (26.1-305.5) × 10(-10) for seaweed collected in 1986. Also a linear relationship was established for (127)I concentrations in seawater and salinity in this area, enabling the estimation of concentration factors for (127)I in F. vesiculosus. The high levels of (129)I and (129)I/(127)I in the Kattegat and their gradually decreasing trend to the Baltic Sea indicates that the most important contribution to the (129)I inventory in the Baltic Sea area comes from Sellafield and La Hague reprocessing plants. With respect to Chernobyl accident, (129)I concentrations in samples collected in 1986 were not much higher than those expected in less contaminated samples from 1982. This supports the view that the contribution of the Chernobyl accident to (129)I in the Baltic region was not significant.


Asunto(s)
Radioisótopos de Cesio/análisis , Accidente Nuclear de Chernóbil , Fucus/química , Radioisótopos de Yodo/análisis , Contaminantes Radiactivos del Agua/análisis , Radiación de Fondo , Océanos y Mares , Monitoreo de Radiación , Suecia
8.
Appl Radiat Isot ; 70(1): 263-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21840221

RESUMEN

The AMS system at CNA has been the first 1MV compact AMS system designed and manufactured by HVE. In this paper we present the experimental set-up for (129)I measurements in this facility. Charge state +3 has been selected at high-energy side and an optimum stripper pressure of 6×10(-3)mbar of argon (mass thickness of about 0.15µgcm(-2)) has been reached to obtain lowest blank values ((129)I/(127)I≅3×10(-13)). The measurements of the reference materials provided by the IAEA have demonstrated the viability of this facility to make routine measurements of (129)I at environmental levels. This blank value obtained is enough for the measurement of most environmental samples and comparable with other reported backgrounds obtained in facilities working at higher energies and higher charge states.


Asunto(s)
Radioisótopos de Yodo/análisis , Aceleradores de Partículas , Radiometría/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Dosis de Radiación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , España
9.
Plant Biol (Stuttg) ; 13(4): 643-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21668605

RESUMEN

The germination of seeds of Eichhornia crassipes in locations distant from the foci of infestation may be a means of dispersal of this invasive plant. Nonetheless, no modern studies have examined the influence of single components on germination, although the influence of temperature, oxygen and redox potential was examined in earlier studies. The effects of pH, conductivity, nitrate, phosphate, potassium, calcium, iron and boron on germination of E. crassipes were determined in seed germination tests. The results showed that external input of nutrients influences germination, since neither pH nor conductivity alone had any effect, but there was a significant increase in germination in growth media containing phosphorus at 3.95 mg·l(-1) (P/L; 95.5%) and boron at 10 mg·l(-1) (B/L; 97.5%); at higher concentrations, the latter was toxic. These findings contribute to knowledge of factors controlling the germination of E. crassipes seeds. Consequently, E. crassipes seeds would find very good conditions for germination in water classified as hypereutrophic, which may play a decisive role in expansion of this plant.


Asunto(s)
Boro/metabolismo , Eichhornia/crecimiento & desarrollo , Germinación/fisiología , Fósforo/metabolismo , Dispersión de Semillas/fisiología , Semillas/crecimiento & desarrollo , Agua/química , Boro/toxicidad , Eichhornia/metabolismo , Concentración de Iones de Hidrógeno
10.
J Environ Radioact ; 102(2): 200-5, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21177003

RESUMEN

Lichen is a symbiosis between algae and fungi. They have for decades been used as bioindicators for atmospheric deposition of heavy metals, organic compounds and radioactive elements. Especially the species Cladonia alpestris and Cladonia rangiferina are important for the food chain lichen-reindeer-man. The concentration of (129)I was determined in lichen samples (Cladonia alpestris) contaminated by fallout from atmospheric nuclear tests explosions and the Chernobyl accident. The samples were collected at Lake Rogen District (62.3°N, 12.4°E) in central Sweden in the periods 1961-1975 and 1987-1998, and analysed with accelerator mass spectrometry (AMS) at CNA (Seville) to study its distribution in different layers. Data on the (137)Cs activity measured previously were also included in this study. The (129)I concentration ranged from (0.95 ± 0.13) × 10(8) at g(-1) in 1961 in the uppermost layer to (14.2 ± 0.5) × 10(8) at g(-1) in 1987 in deepest layer. The (129)I/(137)Cs atom ratio ranged between 0.12 and 0.27 for lichen samples collected in the period 1961-1975, indicating weapons tests fallout. For lichen samples collected between 1987 and 1998 the behaviour of (137)Cs concentrations reflected Chernobyl fallout. The concentrations of the two radionuclides followed each other quite well in the profile, reflecting the same origin for both. From the point of view of the spatial distribution in the lichen, it appears that (129)I was predominantly accumulated in the lowest layer, the opposite to (137)Cs for which the highest amounts were detected systematically in the topmost layer of lichen. This vertical distribution is important for radioecology because lichen is the initial link in the food chain lichen-reindeer-man, and reindeer only graze the upper parts of lichen carpets.


Asunto(s)
Radioisótopos de Cesio/análisis , Accidente Nuclear de Chernóbil , Radioisótopos de Yodo/análisis , Líquenes/química , Monitoreo de Radiación/estadística & datos numéricos , Espectrometría de Masas , Monitoreo de Radiación/métodos , Suecia
12.
Arch Esp Urol ; 62(6): 501-7, 2009 Jul.
Artículo en Inglés, Español | MEDLINE | ID: mdl-19959868

RESUMEN

OBJECTIVE: To describe 8 cases of penile foreign bodies. METHODS/RESULTS: We provide an essentially visual overview of various objects or foreign bodies affecting the penis. CONCLUSIONS: The presence of penile foreign bodies is rarely due to an accident. These objects are placed for a wide variety of reasons, but primarily for erotic or self-arousal purposes. The consequences of penile foreign bodies can be mild or very severe, resulting in penile amputation.


Asunto(s)
Cuerpos Extraños , Pene , Adulto , Anciano , Cuerpos Extraños/etiología , Cuerpos Extraños/terapia , Humanos , Masculino , Adulto Joven
14.
Artículo en Inglés | MEDLINE | ID: mdl-19264148

RESUMEN

The Senegalese sole (Solea senegalensis) is a valuable flatfish for aquaculture, but it presents important reproductive problems in captivity. Spawning is achieved by wild-caught breeders but cultured broodstocks fail to spawn spontaneously and, when they do, eggs are unfertilized. To gain knowledge on the physiological basis underlying this reproductive dysfunction, this study aimed at analyzing comparative hormone levels between wild and cultured broodstocks at the spawning season. The Senegalese sole gonadotropin (GTH) subunits, FSHbeta, LHbeta and GPalpha, were cloned and qualitative (in situ hybridization) and quantitative (real-time PCR) assays developed to analyze pituitary GTH gene expression. In females, FSHbeta and GPalpha mRNA levels were higher in wild than in cultured broodstocks, whereas in males all three subunits were highest in cultured. By ELISA, three GnRH forms were detected in the pituitary, displaying a relative abundance of GnRH2>GnRH1>GnRH3. All GnRHs were slightly more abundant in wild than cultured females, whereas no differences were observed in males. Plasma levels of vitellogenin and sex steroids were also analyzed. Results showed endocrine differences between wild and cultured broodstocks at the spawning period, which could be related to the endocrine failure of the reproductive axis in cultured breeders.


Asunto(s)
Animales Salvajes/metabolismo , Peces Planos/metabolismo , Expresión Génica/genética , Hormona Liberadora de Gonadotropina/metabolismo , Gonadotropinas/genética , Gonadotropinas/metabolismo , Hipófisis/metabolismo , Secuencia de Aminoácidos , Animales , Clonación Molecular , Ensayo de Inmunoadsorción Enzimática , Femenino , Peces Planos/genética , Hormonas Esteroides Gonadales/sangre , Gonadotropinas/análisis , Datos de Secuencia Molecular , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Vitelogeninas/sangre
16.
Actas Urol Esp ; 31(8): 885-94, 2007 Sep.
Artículo en Español | MEDLINE | ID: mdl-18020214

RESUMEN

We present four cases of femoral neuropathy due to urological surgery, first case happened after right lumbotomy twenty years ago and the other three cases in the last four years after iliac incision. We review lesion production mecanism, evolution, treatment and prevention of this rare neurological complication. We do a literature review about this pathology related with urological activity.


Asunto(s)
Neuropatía Femoral/etiología , Procedimientos Quirúrgicos Urológicos/efectos adversos , Adulto , Femenino , Humanos , Plexo Lumbosacro , Masculino , Persona de Mediana Edad
18.
Oral Dis ; 13(3): 303-7, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17448213

RESUMEN

AIM: To classify 163 ameloblastoma cases according to the new WHO Classification of Odontogenic Tumours (2005) and analyse their clinical and microscopic features. METHODS: We studied the clinico-pathological features of 163 ameloblastoma cases from nine regional Latin-American institutions from Mexico and Guatemala. RESULTS: Ameloblastomas comprised 22.7% of all odontogenic tumours. The mean age was 41.4 years for solid ameloblastoma (SA) and 26.3 years for unicystic ameloblastoma (UA) (P < 0.001) and both sexes were almost equally affected. The mandible was mainly affected for both UA and SA. The mean size was 6.2 cm for SA and 6.3 cm for UA cases. The recurrence rate was 21.7% for SA and 12.6% for UA. UA was twice as more frequent than the solid variant. CONCLUSIONS: In this study we found that UA was frequently misdiagnosed as SA; however, there are enough clinical and microscopic features that allow for an accurate differentiation between both types of ameloblastoma that should be recognized for surgical and prognostic purposes. In this study, SA was not found in patients younger than 20 years, UA had a constant myxoid stroma while mature connective tissue was more frequently associated with the solid type.


Asunto(s)
Ameloblastoma/clasificación , Ameloblastoma/patología , Neoplasias Maxilomandibulares/clasificación , Neoplasias Maxilomandibulares/patología , Adulto , Factores de Edad , Femenino , Guatemala , Humanos , Masculino , México , Recurrencia Local de Neoplasia , Estudios Retrospectivos
20.
Actas Urol Esp ; 29(8): 782-6, 2005 Sep.
Artículo en Español | MEDLINE | ID: mdl-16304911

RESUMEN

Fistulas between the orthotopic reservoir and the gastrointestinal tract have low incidence (1.5-2%). Simptomatology is variable, but it's frecuent to find fecaluria. Among 90 new intestinal bladders we show two fistule of new bladder to ileo, with nest postoperatory diagnosis, using retrograde cystografy; one was resolved with next postoperative treatment and the other with open surgery.


Asunto(s)
Enfermedades del Íleon/diagnóstico por imagen , Fístula Urinaria/diagnóstico por imagen , Reservorios Urinarios Continentes/efectos adversos , Anciano , Humanos , Enfermedades del Íleon/terapia , Masculino , Complicaciones Posoperatorias , Radiografía , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/cirugía , Fístula Urinaria/terapia
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