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1.
Phys Rev Lett ; 118(14): 141803, 2017 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-28430473

RESUMO

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.

2.
Nano Lett ; 16(3): 1637-42, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26837636

RESUMO

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%.

3.
J Nematol ; 49(1): 103-113, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28512382

RESUMO

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.

4.
J Chem Phys ; 144(8): 084503, 2016 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-26931708

RESUMO

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.

5.
Nano Lett ; 15(7): 4783-7, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-26052733

RESUMO

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.

6.
Cir Pediatr ; 29(2): 54-57, 2016 Apr 10.
Artigo em Espanhol | MEDLINE | ID: mdl-28139103

RESUMO

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.


Assuntos
Intestinos/anormalidades , Doenças das Glândulas Suprarrenais/diagnóstico por imagem , Criança , Pré-Escolar , Coristoma/diagnóstico por imagem , Diagnóstico por Imagem/métodos , Feminino , Mucosa Gástrica , Humanos , Lactente , Recém-Nascido , Intestinos/diagnóstico por imagem , Laparotomia , Masculino , Estudos Retrospectivos
7.
Ann Rheum Dis ; 74(6): 1011-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24464962

RESUMO

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.


Assuntos
Síndrome Antifosfolipídica/mortalidade , Lúpus Eritematoso Sistêmico/mortalidade , Trombose/mortalidade , Aborto Espontâneo/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Síndrome Antifosfolipídica/complicações , Síndrome Antifosfolipídica/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Epilepsia/etiologia , Feminino , Retardo do Crescimento Fetal/epidemiologia , Humanos , Lactente , Recém-Nascido , Infecções/etiologia , Infecções/mortalidade , Ataque Isquêmico Transitório/etiologia , Livedo Reticular/etiologia , Estudos Longitudinais , Lúpus Eritematoso Sistêmico/complicações , Masculino , Pessoa de Meia-Idade , Gravidez , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Estudos Prospectivos , Embolia Pulmonar/etiologia , Embolia Pulmonar/mortalidade , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Trombocitopenia/etiologia , Trombose/etiologia , Trombose Venosa/etiologia , Trombose Venosa/mortalidade , Adulto Jovem
8.
Analyst ; 140(9): 3082-9, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25685960

RESUMO

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.


Assuntos
Bivalves/metabolismo , Brânquias/metabolismo , Ouro/metabolismo , Nanopartículas Metálicas/análise , Animais , Transporte Biológico , Bivalves/ultraestrutura , Ácido Cítrico/química , Ácido Cítrico/metabolismo , Brânquias/ultraestrutura , Ouro/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão e Varredura , Tamanho da Partícula
9.
Nanomaterials (Basel) ; 14(8)2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38668221

RESUMO

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.

10.
Int J Cancer ; 133(4): 997-1005, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23382028

RESUMO

There are few effective therapies for high-risk sarcomas. Initial chemosensitivity is often followed by relapse. In vitro, mammalian target of rapamycin (mTOR) inhibition potentiates the efficacy of chemotherapy on resistant sarcoma cells. Although sarcoma trials using mTOR inhibitors have been disappointing, these drugs were used as maintenance. We conducted a Phase I/II clinical trial to test the ability of temsirolimus to potentiate the cytotoxic effect of liposomal doxorubicin and present here the dose-finding portion of this study. Adult and pediatric patients with recurrent or refractory sarcomas were treated with increasing doses of liposomal doxorubicin and temsirolimus using a continual reassessment method for escalation, targeting a dose-limiting toxicity rate of 20%. Blood samples were drawn before and after the first dose of temsirolimus in Cycles 1 and 2 for pharmacokinetic analysis. The maximally tolerated dose combination was liposomal doxorubicin 30 mg/m(2) monthly with temsirolimus 20 mg/m(2) weekly. Hematologic toxicity was common but manageable. Dose-limiting toxicities were primarily renal. Concurrent administration of liposomal doxorubicin resulted in increased exposure to sirolimus, the active metabolite of temsirolimus. Thus, the combination of liposomal doxorubicin and temsirolimus is safe for heavily pretreated sarcoma patients. Co-administration with liposomal doxorubicin did not alter temsirolimus pharmacokinetics, but increased exposure to its active metabolite.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Doxorrubicina/uso terapêutico , Sarcoma/tratamento farmacológico , Sirolimo/análogos & derivados , Adolescente , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Criança , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Sirolimo/administração & dosagem , Sirolimo/farmacocinética , Sirolimo/uso terapêutico , Adulto Jovem
11.
J Affect Disord ; 331: 313-321, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36977435

RESUMO

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.


Assuntos
Transtorno Depressivo , Qualidade de Vida , Humanos , Neuroticismo , Ansiedade/terapia , Ansiedade/psicologia , Transtornos de Ansiedade/terapia , Transtornos de Ansiedade/psicologia , Transtorno Depressivo/psicologia
12.
Haemophilia ; 18(1): 75-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21535321

RESUMO

For a long time, physical activities have been contraindicated in haemophiliacs or were restricted to few activities. Sports are nowadays advocated for haemophiliacs. Although various lists of physical activities have been proposed, scuba diving is never mentioned. Thus, with a group of haemophilic volunteers, a study was launched on whether, with strict medical follow-up, scuba diving could be allowed for patients with haemophilia. All the participants followed a training program including theory and assessment. In 6 years, a total of 517 dives were performed by 20 patients with congenital bleeding disorders. Nine were under prophylaxis for haemophilia, and nine received on-demand treatment. Two patients had type I von Willebrand's disease. Among the 20 patients, 12 made 12-153 dives, whereas six made eight dives each. No incident was noted during or after the dives. Thus, scuba diving can be authorized for PWH, if they have none of the specific medical contraindications for diving and if they have received medical training allowing them to manage their disease themselves.


Assuntos
Mergulho , Hemofilia A , Hemofilia B , Doenças de von Willebrand , Adulto , Feminino , Hemofilia A/terapia , Hemofilia B/terapia , Hemorragia/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco/métodos , Segurança , Inquéritos e Questionários , Adulto Jovem , Doenças de von Willebrand/terapia
13.
J Hosp Infect ; 108: 113-119, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33157170

RESUMO

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.


Assuntos
Descontaminação/métodos , Formaldeído/farmacologia , Dispositivos de Proteção Respiratória/virologia , Esterilização/métodos , Adulto , Aerossóis/efeitos adversos , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/virologia , Reutilização de Equipamento , Formaldeído/análise , Humanos , Masculino , Máscaras/tendências , Máscaras/virologia , Equipamento de Proteção Individual/provisão & distribuição , Dispositivos de Proteção Respiratória/provisão & distribuição , SARS-CoV-2/genética , Cloreto de Sódio/análise , Vapor/efeitos adversos , Ventiladores Mecânicos/provisão & distribuição , Ventiladores Mecânicos/virologia
14.
J Theor Biol ; 265(4): 599-603, 2010 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-20665970

RESUMO

We consider a simple model to give a plausible mechanical explanation of what are the actual resting heart rates of mammals optimized for. We study what is the optimal frequency for a viscoelastic fluid circulating in a pulsatile way through a network of tubes and conclude that the heart rate is not optimized to transport blood through the whole net. Rather, actual resting heart rates of mammals happen at frequencies that optimize flow in vessels of radii that correspond to large arteries, which bring oxygenated blood rapidly far away from the heart, towards head and limbs. Our results for the optimal frequencies, obtained using observed radii of femoral arteries in mammals, agree best with the heart rates observed. We find a theoretical allometric relation between optimal flow frequency and radius: nu approximately R(-1). This one, agrees with the exponent obtained when plotting observed heart rates versus radii of both, femoral arteries and carotids in mammals of different sizes, from mice to horses.


Assuntos
Frequência Cardíaca/fisiologia , Mamíferos/fisiologia , Modelos Cardiovasculares , Animais , Circulação Sanguínea/fisiologia , Artérias Carótidas/fisiologia , Vasos Coronários/fisiologia , Cães , Artéria Femoral/anatomia & histologia , Artéria Femoral/fisiologia , Humanos , Permeabilidade , Descanso/fisiologia
15.
Phys Rev E ; 101(1-1): 012117, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32069599

RESUMO

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.

16.
Anal Bioanal Chem ; 394(6): 1671-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19468718

RESUMO

This work describes the use of a new dedicated laboratory-made micro X-ray diffraction system for detecting the phases present in cross-sections of artworks. As an example, the phases present in samples from gilding ceramics and stone sculptures from the heritage of Seville (Spain) were successfully detected using this new system, which takes advantage of various devices developed for synchrotron radiation, and is complemented by the information provided by other techniques.

17.
Clin Exp Dermatol ; 34(7): 800-3, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19077091

RESUMO

Glomeruloid haemangioma is considered a specific marker of POEMS (polyneuropathy, organomegaly, endocrinopathy, M-protein and skin changes) syndrome and it is usually but not always associated with multicentric Castleman's disease. We report a 78-year-old man who presented with a single, red-violet soft nodule with superficial telangiectases on the scalp. Histopathologically, the lesion consisted of lobules of coiled aggregated capillaries that involved the lumina of dilated vascular structures, mimicking renal glomeruli. A collagenous stroma separated the capillary lobules, and eosinophilic, periodic-acid-Schiff positive globules of varying sizes and shapes were seen within the cytoplasm of endothelial cells. Immunohistochemical studies with antibodies against IgA and IgG, and against the kappa and lambda light chains of immunoglobulins showed immunoreactivity within the eosinophilic globules. Results of complete blood count, liver, renal and thyroid function tests, fasting blood sugar measurement, serum levels of oestradiol, testosterone, prolactin and cortisol, serum protein electrophoresis, immunoelectrophoresis and immunofixation yielded normal or negative results. No Bence-Jones proteinuria was found in a sample from a 24-h urine collection. To our knowledge, only two cases of glomeruloid haemangioma have been previously reported in patients without POEMS syndrome. We describe the third case of glomeruloid haemangioma in a patient without features of POEMS syndrome.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Hemangioma/diagnóstico , Síndrome POEMS/diagnóstico , Couro Cabeludo , Neoplasias Cutâneas/diagnóstico , Idoso , Neoplasias de Cabeça e Pescoço/patologia , Hemangioma/patologia , Humanos , Masculino , Neoplasias Cutâneas/patologia
18.
Angew Chem Int Ed Engl ; 48(29): 5313-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19544338

RESUMO

Living on the edge: Three-dimensional reconstructions from electron tomography data recorded from Au/Ce(0.50)Tb(0.12)Zr(0.38)O(2-x) catalysts show that gold nanoparticles (see picture; yellow) are preferentially located on stepped facets and nanocrystal boundaries. An epitaxial relationship between the metal and support plays a key role in the structural stabilization of the gold nanoparticles.

19.
Actas Urol Esp (Engl Ed) ; 43(1): 32-38, 2019.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30100141

RESUMO

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.


Assuntos
Radioisótopos de Flúor , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos , Neoplasias Urológicas/diagnóstico por imagem , Adulto , Idoso , Carcinoma Papilar/diagnóstico por imagem , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/secundário , Carcinoma de Células de Transição/diagnóstico por imagem , Carcinoma de Células de Transição/secundário , Cistadenoma Mucinoso/diagnóstico por imagem , Cistadenoma Mucinoso/secundário , Feminino , Seguimentos , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Neoplasias da Bexiga Urinária/diagnóstico por imagem
20.
Sci Rep ; 8(1): 9755, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29950653

RESUMO

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.

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