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1.
Nanomaterials (Basel) ; 14(8)2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38668221

RESUMEN

Sputtering of silicon in a He magnetron discharge (MS) has been reported as a bottom-up procedure to obtain He-charged silicon films (i.e., He nanobubbles encapsulated in a silicon matrix). The incorporation of heavier noble gases is demonstrated in this work with a synergistic effect, producing increased Ne and Ar incorporations when using He-Ne and He-Ar gas mixtures in the MS process. Microstructural and chemical characterizations are reported using ion beam analysis (IBA) and scanning and transmission electron microscopies (SEM and TEM). In addition to gas incorporation, He promotes the formation of larger nanobubbles. In the case of Ne, high-resolution X-ray photoelectron and absorption spectroscopies (XPS and XAS) are reported, with remarkable dependence of the Ne 1s photoemission and the Ne K-edge absorption on the nanobubble's size and composition. The gas (He, Ne and Ar)-charged thin films are proposed as "solid" targets for the characterization of spectroscopic properties of noble gases in a confined state without the need for cryogenics or high-pressure anvils devices. Also, their use as targets for nuclear reaction studies is foreseen.

2.
J Affect Disord ; 331: 313-321, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-36977435

RESUMEN

BACKGROUND: The personality dimension neuroticism and difficulties in emotional regulation (ER) are two variables closely related to the onset, course, and maintenance of emotional disorders (EDs). The Unified Protocol for the Transdiagnostic Treatment of Emotional Disorders (UP) is a treatment specifically designed to address neuroticism by training in adaptive ER skills and has been shown to be effective in reducing difficulties in ER. However, the specific impact of these variables on treatment outcomes is not entirely clear. The aim of the present study was to explore the moderating role of neuroticism and difficulties in ER regarding the evolution of depressive and anxiety symptoms and quality of life. METHODS: This secondary study included 140 participants diagnosed with EDs, who received the UP in group format as part of an RCT being conducted in different Spanish Public Mental Health Units. RESULTS: The results of this study found that high scores in neuroticism and difficulties in ER were associated with greater severity of depression and anxiety symptomatology, and with poorer quality of life. In addition, difficulties in ER moderated the efficacy of UP regarding anxiety symptoms, and quality of life. No moderating effects were found for depression (p > 0.5). LIMITATIONS: We only evaluated two moderators that may influence UP effectivenes; other key moderators should be analyzed in future. CONCLUSIONS: The identification of specific moderators affecting transdiagnostic interventions outcomes will allow the development of personalized interventions and provide useful information to improve the psychopathology and well-being of people with EDs.


Asunto(s)
Trastorno Depresivo , Calidad de Vida , Humanos , Neuroticismo , Ansiedad/terapia , Ansiedad/psicología , Trastornos de Ansiedad/terapia , Trastornos de Ansiedad/psicología , Trastorno Depresivo/psicología
3.
J Hosp Infect ; 108: 113-119, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33157170

RESUMEN

BACKGROUND: The coronavirus disease 2019 pandemic has caused problems with respirator supplies. Re-use may minimize the impact of the shortage, but requires the availability of an efficient and safe decontamination method. AIM: To determine whether low-temperature-steam-2%-formaldehyde (LTSF) sterilization is effective, preserves the properties of filtering facepiece (FFP) respirators and allows safe re-use. METHODS: Fourteen unused FFP2, FFP3 and N95 respirator models were subjected to two cycles of decontamination cycles. After the second cycle, each model was inspected visually and accumulated residual formaldehyde levels were analysed according to EN 14180. After one and two decontamination cycles, the fit factor (FF) of each model was tested, and penetration tests with sodium chloride aerosols were performed on five models. FINDINGS: Decontamination physically altered three of the 14 models. All of the residual formaldehyde values were below the permissible threshold. Irregular decreases and increases in FF were observed after each decontamination cycle. In the sodium chloride aerosol penetration test, three models obtained equivalent or superior results to those of the FFP classification with which they were marketed, both at baseline and after one and two cycles of decontamination, and two models had lower filtering capacity. CONCLUSION: One and two decontamination cycles using LTSF did not alter the structure of most (11/14) respirators tested, and did not degrade the fit or filtration capacity of any of the analysed respirators. The residual formaldehyde levels complied with EN 14180. This reprocessing method could be used in times of shortage of personal protective equipment.


Asunto(s)
Descontaminación/métodos , Formaldehído/farmacología , Dispositivos de Protección Respiratoria/virología , Esterilización/métodos , Adulto , Aerosoles/efectos adversos , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/virología , Equipo Reutilizado , Formaldehído/análisis , Humanos , Masculino , Máscaras/tendencias , Máscaras/virología , Equipo de Protección Personal/provisión & distribución , Dispositivos de Protección Respiratoria/provisión & distribución , SARS-CoV-2/genética , Cloruro de Sodio/análisis , Vapor/efectos adversos , Ventiladores Mecánicos/provisión & distribución , Ventiladores Mecánicos/virología
4.
Phys Rev E ; 101(1-1): 012117, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32069599

RESUMEN

An approach to obtain the structural properties of additive binary hard-sphere mixtures is presented. Such an approach, which is a nontrivial generalization of the one recently used for monocomponent hard-sphere fluids [S. Pieprzyk, A. C. Branka, and D. M. Heyes, Phys. Rev. E 95, 062104 (2017)2470-004510.1103/PhysRevE.95.062104], combines accurate molecular-dynamics simulation data, the pole structure representation of the total correlation functions, and the Ornstein-Zernike equation. A comparison of the direct correlation functions obtained with the present scheme with those derived from theoretical results stemming from the Percus-Yevick (PY) closure and the so-called rational-function approximation (RFA) is performed. The density dependence of the leading poles of the Fourier transforms of the total correlation functions and the decay of the pair correlation functions of the mixtures are also addressed and compared to the predictions of the two theoretical approximations. A very good overall agreement between the results of the present scheme and those of the RFA is found, thus suggesting that the latter (which is an improvement over the PY approximation) can safely be used to predict reasonably well the long-range behavior, including the structural crossover, of the correlation functions of additive binary hard-sphere mixtures.

5.
Actas Urol Esp (Engl Ed) ; 43(1): 32-38, 2019.
Artículo en Inglés, Español | MEDLINE | ID: mdl-30100141

RESUMEN

INTRODUCTION: New imaging studies have appeared in recent years for the diagnosis and follow-up of metastatic urological tumours. MATERIAL AND METHODS: A total of 41 patients were reviewed with suspected recurrence of a urothelial or kidney tumour, analysing the diagnostic performance of PET-CT scans undertaken between 2013 and 2016. RESULTS: We collected 17 urothelial tumours and 24 renal tumours, with a median follow-up of 30 months. A total of 39.3% of the urothelial tumours were high grade and 29.3% of the kidney tumours were clear cell Fuhrman II. As a whole, the imaging studies detected recurrences in 34 patients. CT was positive in 83% of the patients, while the PET scan was positive in 75.6%, CT/PET coincidence was 50%. The PET scan detected further disease in 41% of the cases compared to 5% by CT. This resulted in a change of therapeutic strategy in 40% of the patients. Sensitivity, specificity, positive predictive value and negative predictive value for the CT and the PET scans were 92% and 92%, 57% and 100%, 92% and 100%, and 57% and 70% respectively. CONCLUSION: The PET scan showed similar sensitivity for urological tumours to the standard imaging techniques but with higher specificity, positive predictive value and negative predictive value. This led to a change in treatment strategy for 40% of the patients in our series. The PET scan will probably become the standard test in the extension and follow-up studies of most urological tumours.


Asunto(s)
Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Radiofármacos , Neoplasias Urológicas/diagnóstico por imagen , Adulto , Anciano , Carcinoma Papilar/diagnóstico por imagen , Carcinoma de Células Renales/diagnóstico por imagen , Carcinoma de Células Renales/secundario , Carcinoma de Células Transicionales/diagnóstico por imagen , Carcinoma de Células Transicionales/secundario , Cistoadenoma Mucinoso/diagnóstico por imagen , Cistoadenoma Mucinoso/secundario , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Renales/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Tomografía de Emisión de Positrones , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen
6.
Sci Rep ; 8(1): 13465, 2018 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-30181588

RESUMEN

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

7.
Sci Rep ; 8(1): 9755, 2018 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-29950653

RESUMEN

In this work, we prepared a series of Ni foam supported Ru-Co, Ru-Co-B and Ru-Co-C catalysts in the form of columnar thin films by magnetron sputtering for the hydrolysis of sodium borohydride. We studied the activity and durability upon cycling. We found a strong activation effect for the Ru-Co-C sample which was the highest ever reported. This catalyst reached in the second cycle an activity 5 times higher than the initial (maximum activity 9310 ml.min-1.gCoRu-1 at 25 °C). Catalytic studies and characterization of the fresh and used samples permitted to attribute the strong activation effect to the following factors: (i) small column width and amorphous character (ii) the presence of Ru and (iii) dry state before each cycle. The presence of boron in the initial composition is detrimental to the durability. Our studies point out to the idea that after the first cycle the activity is controlled by surface Ru, which is the most active of the two metals. Apart from the activation effect, we found that catalysts deactivated in further cycles. We ascribed this effect to the loss of cobalt in the form of hydroxides, showing that deactivation was controlled by the chemistry of Co, the major surface metal component of the alloy. Alloying with Ru is beneficial for the activity but not for the durability, and this should be improved.

8.
J Nematol ; 49(1): 103-113, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28512382

RESUMEN

The present study reports the occurrence of the genus Belonolaimus in the state of Sinaloa, Mexico, associated with native plants (i.e., Ziziphus amole and Stenocereus alamosensis) in a natural coastal ecosystem. Both morphological and molecular approaches were employed to characterize the Sinaloa population. Notwithstanding of some morphological and morphometric variation between Belonolaimus from Sinaloa and other valid species, the characterization indicates that this population might belong to the Belonolaimus longicaudatus species complex. Molecular analyses based on the 28S gene and ITS1-5.8S-ITS2 regions of the ribosomal RNA (rRNA) identified four major clades within Belonolaimus; however, none of the species including B. longicaudatus, B. gracilis, and B. euthychilus were supported as monophyletic; yet monophyly is argued to be a basic requirement of species status. Sequence divergence among different Belonolaimus populations and species varied according to the rRNA dataset (i.e., ITS1-5.8S-ITS2 > 28S > 18S) used, thus showing the importance of using genes with different rates of evolution to estimate species relationships. The fact that Belonolaimus has not been found in other cultivated (including on suitable hosts) areas in Sinaloa and that this population is relatively distant from the common B. longicaudatus groups (i.e., clades A and B) suggests that its appearance was not due to a recent introduction associated with the local agriculture.

9.
Phys Rev Lett ; 118(14): 141803, 2017 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-28430473

RESUMEN

We present direct detection constraints on the absorption of hidden-photon dark matter with particle masses in the range 1.2-30 eV c^{-2} with the DAMIC experiment at SNOLAB. Under the assumption that the local dark matter is entirely constituted of hidden photons, the sensitivity to the kinetic mixing parameter κ is competitive with constraints from solar emission, reaching a minimum value of 2.2×10^{-14} at 17 eV c^{-2}. These results are the most stringent direct detection constraints on hidden-photon dark matter in the galactic halo with masses 3-12 eV c^{-2} and the first demonstration of direct experimental sensitivity to ionization signals <12 eV from dark matter interactions.

10.
Semergen ; 43(8): 578-584, 2017.
Artículo en Español | MEDLINE | ID: mdl-28318909

RESUMEN

The urinary incontinence is a highly prevalent symptom in the adult female population. It has important psychosocial and economic connotations, and affects the quality of life of these patients. As it is an under-diagnosed problem due to patients not always consulting for it, it is very important to keep this in mind and to provide an opportunistic screening from Primary Health Care. It is difficult to determine the costs of this, but it is estimated to be the 2% of the health budget. Because of all of this, it is very important to know how to make a correct diagnose of this condition, to determine the different types of incontinence, possible causes, and treatments available. The purpose of this review is to show the different diagnostic and therapeutic tools available, to show the Primary Health Care role in this condition, and when to refer to specialist care.


Asunto(s)
Atención Primaria de Salud/métodos , Calidad de Vida , Incontinencia Urinaria/terapia , Femenino , Humanos , Tamizaje Masivo/métodos , Prevalencia , Derivación y Consulta/organización & administración , Incontinencia Urinaria/diagnóstico , Incontinencia Urinaria/epidemiología
11.
Actas Urol Esp ; 41(7): 465-470, 2017 Sep.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28325529

RESUMEN

OBJECTIVE: To assess the efficacy of treatment with transcutaneous posterior tibial nerve stimulation (TPTNS) in patients with urge urinary incontinence, of neurogenic or nonneurogenic origin, refractory to first-line therapeutic options. MATERIAL AND METHODS: We included 65 patients with urge urinary incontinence refractory to medical treatment. A case history review, a urodynamic study and a somatosensory evoked potentials (SEP) study were conducted before the TPTNS, studying the functional urological condition by means of a voiding diary. The treatment consisted of 10 weekly sessions of TPTNS lasting 30minutes. RESULTS: Some 57.7% of the patients showed abnormal tibial SEPs, and 42% showed abnormal pudendal SEPs. A statistically significant symptomatic improvement was observed in all clinical parameters after treatment with TPTNS, and 66% of the patients showed an overall improvement, regardless of sex, the presence of underlying neurological disorders, detrusor hyperactivity in the urodynamic study or SEP disorders. There were no adverse effects during the treatment. CONCLUSIONS: TPTNS is an effective and well tolerated treatment in patients with urge incontinence refractory to first-line therapies and should be offered early in the treatment strategy. New studies are needed to identify the optimal parameters of stimulation, the most effective treatment protocols and long-term efficacy, as well as its applicability to patients with a neurogenic substrate.


Asunto(s)
Estimulación Eléctrica Transcutánea del Nervio , Incontinencia Urinaria de Urgencia/terapia , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Nervio Tibial , Incontinencia Urinaria de Urgencia/etiología
12.
Actas Urol Esp ; 41(6): 376-382, 2017.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28161070

RESUMEN

OBJECTIVE: To analyze the expression of metalloprotein 11 (MMP11) in cultured fibroblasts obtained from human prostate tumors with different clinical and pathological characteristics. MATERIAL AND METHODS: For this study we analyzed samples of transrectal prostate biopsies from tumors with different characteristics, treated with or whithout androgen deprivation (AD). After optimization of the culture method, fibroblasts were isolated and cultured to perform the study (PCR) of MMP11 mRNA. RESULTS: Finally, 37 cases were studied: 5 samples of benign prostatic hyperplasia, 14 cases with localized neoplasms (7 high-risk according to the D'Amico classification), 5 with metastasic tumors (bone metastases), and 13 treated with AD therapy, of which 6 fulfilled the requirements to be defined as resistant to castration. In tumors without AD therapy, MMP11 expression was significantly higher (P=.001) in fibroblasts of higher grade tumors. A significant (P=.001) correlation was found between PSA and expression of MMP11 in fibroblast s and a significant increase of MMP11 expression in metastatic tumors. In tumors with AD therapy, a significantly greater expression of MMP11 was observed in resistant to castration patients than in those sensitive to castration (P=.003). CONCLUSION: In advanced prostate tumors or in stages of increased tumor aggressiveness, the production of MMP11 by fibroblasts is significantly greater than in non-metastatic tumors or in AD sensitive tumors.


Asunto(s)
Fibroblastos Asociados al Cáncer/metabolismo , Metaloproteinasa 11 de la Matriz/biosíntesis , Neoplasias de la Próstata Resistentes a la Castración/patología , Neoplasias de la Próstata/patología , Anciano , Biomarcadores de Tumor/biosíntesis , Células Cultivadas , Humanos , Masculino , Persona de Mediana Edad , Terapia Molecular Dirigida , Estadificación de Neoplasias , Neoplasias de la Próstata/terapia , Neoplasias de la Próstata Resistentes a la Castración/terapia
13.
J Chem Phys ; 144(8): 084503, 2016 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-26931708

RESUMEN

A theoretical study on the equation of state and the critical point behavior of hard-core double-Yukawa fluids is presented. Thermodynamic perturbation theory, restricted to first order in the inverse temperature and having the hard-sphere fluid as the reference system, is used to derive a relatively simple analytical equation of state of hard-core multi-Yukawa fluids. Using such an equation of state, the compressibility factor and phase behavior of six representative hard-core double-Yukawa fluids are examined and compared with available simulation results. The effect of varying the parameters of the hard-core double-Yukawa intermolecular potential on the location of the critical point is also analyzed using different perspectives. The relevance of this analysis for fluids whose molecules interact with realistic potentials is also pointed out.

14.
Nano Lett ; 16(3): 1637-42, 2016 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-26837636

RESUMEN

Energy dispersive X-ray spectrometry is used to extract a quantitative 3D composition profile of heterostructured nanowires. The analysis of hypermaps recorded along a limited number of projections, with a preliminary calibration of the signal associated with each element, is compared to the intensity profiles calculated for a model structure with successive shells of circular, elliptic, or faceted cross sections. This discrete tomographic technique is applied to II-VI nanowires grown by molecular beam epitaxy, incorporating ZnTe and CdTe and their alloys with Mn and Mg, with typical size down to a few nanometers and Mn or Mg content as low as 10%.

15.
Cir Pediatr ; 29(2): 54-57, 2016 Apr 10.
Artículo en Español | MEDLINE | ID: mdl-28139103

RESUMEN

PURPOUSE: Intestinal duplications (DI) are rare congenital anomalies (1/10.000 new born). We analyze the clinical characteristics, management and treatment of intestinal duplications in our center. MATERIALS AND METHODS: We perform a retrospectively descriptive analysis review by the DI confirmed by histological studies since 1993-2014 in our center. The variables analyzed are: age, sex, clinical presentation, localization, anatomical type, associated diseases, heterotopic tissue, treatment and complications. RESULTS: We found ten patients diagnosed with DI. 60% were male, the middle age was 2.72 years (12 days-7 years). In the clinical presentation 30% presents acute abdomen, another 30% gastrointestinal bleeding and 30% were prenatal diagnosed. Imaging studies were echography, gammagraphy, magnetic resonance imaging and intestinal transit contrast. The most frequent localization was the yeyuno-ileal (60%) with cystic predominance; the gastric, duodenal colic was 10% respectively; an ectopic localization was a suprarenal mass. The treatment was a complete resection by laparotomy in eight cases and laparoscopic in two In the duodenal duplication, we perform a partial resection and mucosectomy. In 60% was necessary the intestinal resection. In anatomy pathologic results, gastric tissue (heterotopic tissue) was present in 70% and pancreatic tissue in 10%. We report an intussusception postsurgical as a complication. CONCLUSIONS: The preoperative diagnosis is rare, although prenatal diagnosis is increasing. Clinical manifestations are associated with the location of the DI and the existence of heterotopic gastric mucosa. Laparoscopy is currently the treatment of choice in uncomplicated cases.


OBJETTIVO: Las duplicaciones intestinales (DI) son anomalías congénitas raras (1/10.000 recién nacidos vivos). Analizamos las características clínicas, manejo y tratamiento de DI en nuestro centro. MATERIAL Y METODOS: Análisis descriptivo retrospectivo de las DI confirmados por histología desde 1993-2014 en nuestro centro. Revisamos como variables: edad, sexo, presentación clínica, localización, tipo anatómico, enfermedades asociadas, presencia de tejido heterotópico, tratamiento y complicaciones. RESULTADOS: Se diagnosticaron 10 pacientes con DI, 6 fueron varones, la edad media fue de 2,72 años (12 días-7 años). 3 debutaron con abdomen agudo; otros 3 con hemorragia digestiva alta, 2 con masa abdominal; uno con obstrucción intestinal y uno con dolor crónico. De estos el 30% tuvo diagnóstico prenatal. Los estudios de imagen incluyeron ecografía, gammagrafía, resonancia magnética y tránsito intestinal. La localización anatómica más frecuente fue yeyuno-ileal (60%) de predominio quístico; la gástrica, duodenal, cólica fue de 10% respectivamente; y una localización ectópica con sospecha de masa suprarrenal. El tratamiento consistió en resección completa mediante laparotomía en 8 casos y laparoscopía en dos. En la DI duodenal que se practicó mucosectomía y resección parcial. En 6 casos se llegó a realizar resección intestinal. Se halló tejido gástrico heterotópico en 7 y pancreático en uno. Como complicaciones destaca un caso de invaginación intestinal postoperatoria. CONCLUSIONES: El diagnóstico preoperatorio es poco frecuente, aunque se está incrementando el diagnóstico prenatal. Las manifestaciones clínicas se relacionan con la localización de la DI y con la existencia de mucosa heterotópica gástrica. Actualmente la laparoscopia es el tratamiento de elección en casos no complicados.


Asunto(s)
Intestinos/anomalías , Enfermedades de las Glándulas Suprarrenales/diagnóstico por imagen , Niño , Preescolar , Coristoma/diagnóstico por imagen , Diagnóstico por Imagen/métodos , Femenino , Mucosa Gástrica , Humanos , Lactante , Recién Nacido , Intestinos/diagnóstico por imagen , Laparotomía , Masculino , Estudios Retrospectivos
16.
Nano Lett ; 15(7): 4783-7, 2015 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-26052733

RESUMEN

In this Letter we report on the exploration of axial metal/semiconductor (Al/Ge) nanowire heterostructures with abrupt interfaces. The formation process is enabled by a thermal induced exchange reaction between the vapor-liquid-solid grown Ge nanowire and Al contact pads due to the substantially different diffusion behavior of Ge in Al and vice versa. Temperature-dependent I-V measurements revealed the metallic properties of the crystalline Al nanowire segments with a maximum current carrying capacity of about 0.8 MA/cm(2). Transmission electron microscopy (TEM) characterization has confirmed both the composition and crystalline nature of the pure Al nanowire segments. A very sharp interface between the ⟨111⟩ oriented Ge nanowire and the reacted Al part was observed with a Schottky barrier height of 361 meV. To demonstrate the potential of this approach, a monolithic Al/Ge/Al heterostructure was used to fabricate a novel impact ionization device.

17.
Analyst ; 140(9): 3082-9, 2015 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25685960

RESUMEN

The methodology termed scanning transmission electron microscopy in scanning electron microscopy (STEM-in-SEM) has been used in this work to study the uptake of citrate stabilized gold nanoparticles (AuNPs) (average particle sizes of 23.5 ± 4.0 nm) into tissue samples upon in vitro exposure of the dissected gills of the Ruditapes philippinarum marine bivalve to the nanoparticle suspensions. The STEM-in-SEM methodology has been optimized for achieving optimum resolution under SEM low voltage operating conditions (20-30 kV). Based on scanning microscope assessments and resolution testing (SMART), resolutions well below 10 nm were appropriately achieved by working at magnifications over 100k×, with experimental sample thickness between 300 and 200 nm. These relatively thick slices appear to be stable under the beam and help avoid NP displacement during cutting. We herein show that both localizing of the internalized nanoparticles and imaging of ultrastructural disturbances in gill tissues are strongly accessible due to the improved resolution, even at sample thicknesses higher than those normally employed in standard TEM techniques at higher voltages. Ultrastructural imaging of bio-nano features in bioaccumulation experiments have been demonstrated in this study.


Asunto(s)
Bivalvos/metabolismo , Branquias/metabolismo , Oro/metabolismo , Nanopartículas del Metal/análisis , Animales , Transporte Biológico , Bivalvos/ultraestructura , Ácido Cítrico/química , Ácido Cítrico/metabolismo , Branquias/ultraestructura , Oro/química , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Transmisión de Rastreo , Tamaño de la Partícula
18.
Ann Rheum Dis ; 74(6): 1011-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24464962

RESUMEN

OBJECTIVES: To assess the prevalence of the main causes of morbi-mortality in the antiphospholipid syndrome (APS) during a 10-year-follow-up period and to compare the frequency of early manifestations with those that appeared later. METHODS: In 1999, we started an observational study of 1000 APS patients from 13 European countries. All had medical histories documented when entered into the study and were followed prospectively during the ensuing 10 years. RESULTS: 53.1% of the patients had primary APS, 36.2% had APS associated with systemic lupus erythematosus and 10.7% APS associated with other diseases. Thrombotic events appeared in 166 (16.6%) patients during the first 5-year period and in 115 (14.4%) during the second 5-year period. The most common events were strokes, transient ischaemic attacks, deep vein thromboses and pulmonary embolism. 127 (15.5%) women became pregnant (188 pregnancies) and 72.9% of pregnancies succeeded in having one or more live births. The most common obstetric complication was early pregnancy loss (16.5% of the pregnancies). Intrauterine growth restriction (26.3% of the total live births) and prematurity (48.2%) were the most frequent fetal morbidities. 93 (9.3%) patients died and the most frequent causes of death were severe thrombosis (36.5%) and infections (26.9%). Nine (0.9%) cases of catastrophic APS occurred and 5 (55.6%) of them died. The survival probability at 10 years was 90.7%. CONCLUSIONS: Patients with APS still develop significant morbidity and mortality despite current treatment. It is imperative to increase the efforts in determining optimal prognostic markers and therapeutic measures to prevent these complications.


Asunto(s)
Síndrome Antifosfolípido/mortalidad , Lupus Eritematoso Sistémico/mortalidad , Trombosis/mortalidad , Aborto Espontáneo/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Síndrome Antifosfolípido/complicaciones , Síndrome Antifosfolípido/epidemiología , Niño , Preescolar , Estudios de Cohortes , Epilepsia/etiología , Femenino , Retardo del Crecimiento Fetal/epidemiología , Humanos , Lactante , Recién Nacido , Infecciones/etiología , Infecciones/mortalidad , Ataque Isquémico Transitorio/etiología , Livedo Reticularis/etiología , Estudios Longitudinales , Lupus Eritematoso Sistémico/complicaciones , Masculino , Persona de Mediana Edad , Embarazo , Resultado del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Estudios Prospectivos , Embolia Pulmonar/etiología , Embolia Pulmonar/mortalidad , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/mortalidad , Trombocitopenia/etiología , Trombosis/etiología , Trombosis de la Vena/etiología , Trombosis de la Vena/mortalidad , Adulto Joven
19.
Nat Commun ; 5: 5229, 2014 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-25354473

RESUMEN

Proton exchange membrane fuel cell is one of the most promising zero-emission power sources for automotive or stationary applications. However, their cost and lifetime remain the two major key issues for a widespread commercialization. Consequently, much attention has been devoted to optimizing the membrane/electrode assembly that constitute the fuel cell core. The electrodes consist of carbon black supporting Pt nanoparticles and Nafion as the ionomer binder. Although the ionomer plays a crucial role as ionic conductor through the electrode, little is known about its distribution inside the electrode. Here we report the three-dimensional morphology of the Nafion thin layer surrounding the carbon particles, which is imaged using electron tomography. The analyses reveal that doubling the amount of Nafion in the electrode leads to a twofold increase in its degree of coverage of the carbon, while the thickness of the layer, around 7 nm, is unchanged.

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