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1.
Sci Rep ; 13(1): 9639, 2023 Jun 14.
Article in English | MEDLINE | ID: mdl-37316525

ABSTRACT

The use of magnetic vector tomography/laminography has opened a 3D experimental window to access the magnetization at the nanoscale. These methods exploit the dependence of the magnetic contrast in transmission to recover its 3D configuration. However, hundreds of different angular projections are required leading to large measurement times. Here we present a fast method to dramatically reduce the experiment time specific for quasi two-dimensional magnetic systems. The algorithm uses the Beer-Lambert equation in the framework of X-ray transmission microscopy to obtain the 3D magnetic configuration of the sample. It has been demonstrated in permalloy microstructures, reconstructing the magnetization vector field with a reduced number of angular projections obtaining quantitative results. The throughput of the methodology is × 10-× 100 times faster than conventional magnetic vector tomography, making this characterization method of general interest for the community.

2.
Obes Surg ; 33(4): 1211-1217, 2023 04.
Article in English | MEDLINE | ID: mdl-36849786

ABSTRACT

BACKGROUND: Bariatric surgery (BS) has a significant impact on body composition. The purpose of the study is to evaluate the usefulness of musculoskeletal ultrasound (MUS) to bioelectrical impedance (BIA) in the follow-up of patients undergoing BS in terms of body composition and quality of life (QoL). METHODS: This is a prospective pilot study including 32 subjects (75% female, mean age: 49.15 ± 1.9 years) who underwent BS. Fat mass (FM), lean mass (LM), and skeletal muscle index (SMI) were calculated by BIA. MUS measured subcutaneous fat (SF) and thigh muscle thickness (TMT) of the quadriceps. QoL was assessed by the Moorehead-Ardelt questionnaire. All these measurements were performed 1 month prior to BS and at 12-month follow-up. RESULTS: The mean BMI decreased by 6.63 ± 1.25 kg/m2 (p=0.001). We observed significant reductions in FM (p=0.001) and SF (p=0.007) and in LM (p=0.001) but not in SMI and TMT. We found a correlation between the FM and SF (pre-surgical, r=0.42, p=0.01; post-surgical, r=0.52, p=0.003) and between SMI and TMT (pre-surgical, r=0.35, p=0.04; post-surgical, r=0.38, p=0.03). QoL test showed significant improvement (p=0.001). In addition, a correlation between the QoL questionnaire and TMT post-surgery (r=0.91, p=0.019) was observed. However, we did not find any statistically significant correlation between QoL assessment and SMI or LM. CONCLUSIONS: Our results suggest that MUS can be complementary to BIA for the evaluation and the follow-up of body composition after BS. TMT of quadriceps can provide relevant information about regional sarcopenia and has a significant correlation with QoL.


Subject(s)
Bariatric Surgery , Obesity, Morbid , Humans , Female , Middle Aged , Male , Quality of Life , Pilot Projects , Obesity, Morbid/surgery , Prospective Studies , Body Composition/physiology , Bariatric Surgery/methods , Body Mass Index , Electric Impedance
3.
Nat Commun ; 11(1): 6382, 2020 Dec 14.
Article in English | MEDLINE | ID: mdl-33318487

ABSTRACT

The knowledge of how magnetization looks inside a ferromagnet is often hindered by the limitations of the available experimental methods which are sensitive only to the surface regions or limited in spatial resolution. Here we report a vector tomographic reconstruction based on soft X-ray transmission microscopy and magnetic dichroism data, which has allowed visualizing the three-dimensional magnetization in a ferromagnetic thin film heterostructure. Different non-trivial topological textures have been resolved and the determination of their topological charge has allowed us to identify a Bloch point and a meron-like texture. Our method relies only on experimental data and might be of wide application and interest in 3D nanomagnetism.

4.
SEMERGEN, Soc. Esp. Med. Rural Gen. (Ed. Impr.) ; 46(1): 46-52, ene.-feb. 2020. tab, graf
Article in Spanish | IBECS | ID: ibc-194407

ABSTRACT

OBJETIVOS: Analizar el estado de salud de los pacientes con diabetes tipo 2 (DM2) en un centro de salud urbano y valorar el seguimiento realizado por parte de los profesionales sanitarios. Analizar las terapias farmacológicas en pacientes con DM2, así como valorar la individualización atendiendo a sus comorbilidades. MATERIAL Y MÉTODOS: Análisis descriptivo y transversal de pacientes con DM2. De un total de 920 pacientes se obtuvo una muestra aleatorizada y simple de 460 individuos, de los cuales se recogieron los parámetros relacionados con las comorbilidades asociadas y el tratamiento integral de la DM2. RESULTADOS: Nos encontramos ante una muestra de 460 pacientes (42,4% mujeres) con una edad media de 67,1 años (DE=13,07). El valor medio de su última HbA1c fue 6,75% (DE=1,24). El 83,7% cumplía con los objetivos individualizados propuestos de HbA1c atendiendo a su edad y comorbilidades. El 65,43% de los pacientes contaba con un seguimiento subóptimo por parte de los profesionales sanitarios. Con respecto a la adecuación del tratamiento, el 19,8% contaba con asociaciones farmacológicas no recomendadas o fármacos aplicados fuera de ficha técnica. El 74,3% contaba con un tratamiento integral de la DM2 mejorable. CONCLUSIONES: Aunque el 83,7% de los pacientes presentaba un buen control de la HbA1c, el tratamiento es glucocéntrico y mejorable en un alto porcentaje de los pacientes (74,3%). Dado que la terapia debe ajustarse a las necesidades de cada paciente, y siendo el IMC un factor determinante para la selección del tratamiento, llama la atención que en el 44,13% de los pacientes no esté registrado en su historia clínica


OBJECTIVES: To determine the health status of patients with type 2 diabetes (T2D) in an urban Primary Healthcare centre, and to assess the follow-up carried out by health professionals. To analyse the pharmacological treatment in patients with T2D, as well as to assess the individualisation according to their comorbidities. MATERIAL AND METHODS: Descriptive and cross-sectional analysis conducted on patients with DM2. Out of a total of 920 patients, a randomised and simple sample of 460 individuals was obtained, from which the parameters related to associated comorbidities and the integral treatment of T2D were collected. RESULTS: The study included 460 patients (42.4% women) with a mean age of 67.1 years (SD=13.07). The mean value of their last HbA1c was 6.75% (SD=1.24). The large majority (83.7%) fulfilled the proposed individualised HbA1c objectives according to their age and comorbidities. Approximately two-thirds (65.43%) of patients had a suboptimal follow-up by health professionals. As regards the suitability of the treatment, 19.8% had non-recommended pharmacological combinations or drugs applied outside the indications of the data sheet. A comprehensive T2D treatment that could be improved was observed in 74.3%. CONCLUSIONS: Although 83.7% of patients had good control of HbA1c, the treatment is centred on blood glucose and improvable in a high percentage of patients (74.3%). Given that the therapy must be adjusted to the needs of each patient, and since the BMI (body mass index) is a determining factor for the selection of treatment, it is striking that it is not recorded in the clinical histories of 44.13% of the patients


Subject(s)
Humans , Male , Female , Middle Aged , Aged , Aged, 80 and over , Blood Glucose/drug effects , Diabetes Mellitus, Type 2/drug therapy , Glycated Hemoglobin/analysis , Hypoglycemic Agents/administration & dosage , Body Mass Index , Cross-Sectional Studies , Diabetes Mellitus, Type 2/physiopathology , First Aid
5.
Nanotechnology ; 31(2): 025702, 2020 Jan 10.
Article in English | MEDLINE | ID: mdl-31546237

ABSTRACT

The sensitivity of circularly polarized x-ray resonant magnetic scattering (CXRMS) to chiral asymmetry has been demonstrated. The study was performed on a 2D array of Permalloy (Py) square nanomagnets of 700 nm lateral size arranged in a chess pattern, in a square lattice of 1000 nm lattice parameter. Previous x-ray magnetic circular dichroism photoemission electron microscopy (XMCD-PEEM) images on this sample showed the formation of vortices at remanence and a preference in their chiral state. The magnetic hysteresis loops of the array along the diagonal axis of the squares indicate a non-negligible and anisotropic interaction between vortices. The intensity of the magnetic scattering using circularly polarized light along one of the diagonal axes of the square magnets becomes asymmetric in intensity in the direction transversal to the incident plane at fields where the vortex states are formed. The asymmetry sign is inverted when the direction of the applied magnetic field is inverted. The result is the expected in the presence of an unbalanced chiral distribution. The effect is observed by CXRMS due to the interference between the charge scattering and the magnetic scattering.

6.
Clin Transl Oncol ; 22(5): 782-785, 2020 May.
Article in English | MEDLINE | ID: mdl-31359339

ABSTRACT

INTRODUCTION: CD47 over expression has been reported in several tumor subtypes. CD47 interacts with SIRPalpha on macrophages inhibiting phagocytic signal, providing a survival advantage to tumor. CD47, therefore, represents a valuable target for immunotherapy and is currently under clinical investigation. We aimed to study CD47 expression in Hodgkin Reed Sternberg cells (HRS). METHODS: We tested a polyclonal CD47 antibody (LifeSpan Biosciences, Seattle, WA) expression along with classical HRS cell markers on a tissue array of 16 classical Hodgkin Lymphoma (CHL) tumor biopsies obtained from newly diagnosed, non-selected patients (8 Female, 8 Male patients) in our institution from October 2016 to January 2018. Histologic subtypes were nodular sclerosis in 11 cases, mixed Cellularity in 3 cases and lymphocyte rich in 2 additional cases. Median age was 53 years (Range: 8, 74). Early stage disease was found in three patients without unfavorable prognostic factors according to EORTC and GHSG criteria, one patient with unfavorable prognostic factors and nine patients had advanced disease. Bulk disease was present in one patient. Normal lymphoid tissue and normal prostate epithelium were used as normal controls as recommended by manufacturer. Approval from the Local Ethical committee was obtained before any analysis. RESULTS: CD47 was overexpressed on all HRS cells with a characteristic dot-like pattern in 13/13 cases of CHL. HRS clearly expressed CD47 more intensely than infiltrating T and stromal cells. DISCUSSION: We propose that HRS cells, by up-regulating CD47, might avoid innate immunity check on tumor growth, which could be circumvented using blocking monoclonal antibodies.


Subject(s)
CD47 Antigen/metabolism , Hodgkin Disease/pathology , Reed-Sternberg Cells/metabolism , Adolescent , Adult , Aged , Biomarkers, Tumor/metabolism , Child , Female , Hodgkin Disease/metabolism , Humans , Male , Middle Aged , Tissue Array Analysis , Young Adult
7.
Semergen ; 46(1): 46-52, 2020.
Article in Spanish | MEDLINE | ID: mdl-31331768

ABSTRACT

OBJECTIVES: To determine the health status of patients with type 2 diabetes (T2D) in an urban Primary Healthcare centre, and to assess the follow-up carried out by health professionals. To analyse the pharmacological treatment in patients with T2D, as well as to assess the individualisation according to their comorbidities. MATERIAL AND METHODS: Descriptive and cross-sectional analysis conducted on patients with DM2. Out of a total of 920 patients, a randomised and simple sample of 460 individuals was obtained, from which the parameters related to associated comorbidities and the integral treatment of T2D were collected. RESULTS: The study included 460 patients (42.4% women) with a mean age of 67.1 years (SD=13.07). The mean value of their last HbA1c was 6.75% (SD=1.24). The large majority (83.7%) fulfilled the proposed individualised HbA1c objectives according to their age and comorbidities. Approximately two-thirds (65.43%) of patients had a suboptimal follow-up by health professionals. As regards the suitability of the treatment, 19.8% had non-recommended pharmacological combinations or drugs applied outside the indications of the data sheet. A comprehensive T2D treatment that could be improved was observed in 74.3%. CONCLUSIONS: Although 83.7% of patients had good control of HbA1c, the treatment is centred on blood glucose and improvable in a high percentage of patients (74.3%). Given that the therapy must be adjusted to the needs of each patient, and since the BMI (body mass index) is a determining factor for the selection of treatment, it is striking that it is not recorded in the clinical histories of 44.13% of the patients.


Subject(s)
Blood Glucose/drug effects , Diabetes Mellitus, Type 2/drug therapy , Glycated Hemoglobin/analysis , Hypoglycemic Agents/administration & dosage , Aged , Aged, 80 and over , Body Mass Index , Cross-Sectional Studies , Diabetes Mellitus, Type 2/physiopathology , Female , Humans , Male , Middle Aged , Primary Health Care
8.
Sci Rep ; 8(1): 12374, 2018 Aug 17.
Article in English | MEDLINE | ID: mdl-30120346

ABSTRACT

We have studied two nanomagnet systems with strong (Co/Pd multilayers) and weak (NdCo alloy films) stray magnetic fields by probing the out-of-plane magnetic states with superconducting vortices. The hybrid samples are made of array of nanomagnets embedded in superconducting Nb thin films. The vortex motion detects relevant magnetic state features, since superconducting vortices are able to discriminate between different magnetic stray field strengths and directions. The usual matching effect between the superconducting vortex lattice and the periodic pinning array can be quenched by means of disorder magnetic potentials with strong stray fields at random. Ordered stray fields retrieve the matching effect and yield asymmetry and shift in the vortex dissipation signal. Furthermore vortices can discriminate the sizes of the nanomagnet magnetic domains, detecting magnetic domain sizes as small as 70 nm. In addition, we observe that the vortex cores play the crucial role instead of the supercurrents around the vortex.

9.
BMC Infect Dis ; 18(1): 189, 2018 04 19.
Article in English | MEDLINE | ID: mdl-29673334

ABSTRACT

BACKGROUND: To evaluate the predictive value of analytical markers of full blood count that can be assessed in the emergency department for HIV infected patients, with community-acquired pneumonia (CAP). METHODS: Prospective 3-year study including all HIV-infected patients that went to our emergency department with respiratory clinical infection, more than 24-h earlier they were diagnosed with CAP and required admission. We assessed the different values of the first blood count performed on the patient as follows; total white blood cells (WBC), neutrophils, lymphocytes (LYM), basophils, eosinophils (EOS), red blood cells (RBC), hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration, mean corpuscular hemoglobin, red blood cell distribution width (RDW), platelets (PLT), mean platelet volume, and platelet distribution width (PDW). The primary outcome measure was 30-day mortality and the secondary, admission to an intensive care unit (ICU). The predictive power of the variables was determined by statistical calculation. RESULTS: One hundred sixty HIV-infected patients with pneumonia were identified. The mean age was 42 (11) years, 99 (62%) were male, 79 (49%) had ART. The main route of HIV transmission was through parenteral administration of drugs. Streptococcus pneumonia was the most frequently identified etiologic agent of CAP The univariate analysis showed that the values of PLT (p < 0.009), EOS (p < 0.033), RDW (p < 0.033) and PDW (p < 0.09) were predictor of mortality, but after the logistic regression analysis, no variable was shown as an independent predictor of mortality. On the other hand, higher RDW (OR = 1.2, 95% CI 1.1-1.4, p = 0.013) and a lower number of LYM (OR 2.2, 95% CI 1.1-2.2; p = 0.035) were revealed as independent predictors of admission to ICU. CONCLUSION: Red blood cell distribution and lymphocytes were the most useful predictors of disease severity identifying HIV infected patients with CAP who required ICU admission.


Subject(s)
Blood Cell Count , Community-Acquired Infections/mortality , HIV Infections/complications , Pneumonia/mortality , Adult , Community-Acquired Infections/etiology , Erythrocyte Indices , Female , HIV Infections/mortality , Hematocrit , Hospitalization/statistics & numerical data , Humans , Intensive Care Units/statistics & numerical data , Male , Middle Aged , Pneumonia/drug therapy , Pneumonia/etiology , Prognosis , Prospective Studies
10.
J Phys Chem B ; 122(2): 745-756, 2018 01 18.
Article in English | MEDLINE | ID: mdl-28885023

ABSTRACT

We report a surface X-ray diffraction study of the crystalline structure changes and critical behavior across the (3√2 × âˆš2)R45° → (√2 × âˆš2)R45° surface phase transition at 360 K for 0.5 monolayers of Sn on Cu(100). The phase transition is of the order-disorder type and is due to the disordering of the Cu atomic vacancies present in the low temperature phase. Two different atomic sites for Sn atoms, characterized by two different heights, are maintained across the surface phase transition.

11.
Diabet Med ; 33(10): 1422-6, 2016 10.
Article in English | MEDLINE | ID: mdl-26870914

ABSTRACT

AIMS: To determine the long-term outcome of continuous subcutaneous insulin infusion (CSII) in Type 1 diabetes according to Catalan National Health Service indications. METHODS: Retrospective observational study including 178 patients with Type 1 diabetes who started CSII treatment in our centre (2003-2008). All patients were followed in our CSII programme for outpatients for at least 5 years. Data on annual HbA1c levels were collected, and the main indication for starting CSII was analysed. RESULTS: Twenty-seven of 178 patients were excluded because of loss to follow-up or withdrawal from CSII, thus 151 patients (aged 37.4 ± 10.5 years, 64% women) were analysed. The main indications for starting CSII were suboptimal metabolic control (60.9%), severe hypoglycaemia/hypoglycaemia unawareness (25.5%) and others (13.6%). HbA1c was 64 ± 13 mmol/mol (8.0 ± 1.2%) at the start of CSII and 62 ± 13 mmol/mol (7.8 ± 1.2%) after 5 years in the total cohort (P = 0.1). The severe hypoglycaemia rates were 0.66 ± 1.61 and 0.17 ± 0.42 episodes/patient/year (P < 0.001). In patients with suboptimal metabolic control, HbA1c decreased from 68 ± 12 mmol/mol (8.4 ± 1.1%) to 64 ± 14 mmol/mol (8.0 ± 1.3%) (P = 0.016), with 37.4% of those in this group having an HbA1c ≤ 58 mmol/mol (7.5%) after 5 years. In patients starting CSII due to severe hypoglycaemia the problem was considered resolved in 93%, and in 64% of those starting CSII because of suboptimal glycaemic control, HbA1c improved significantly. CONCLUSIONS: CSII therapy achieves and maintains its efficacy mainly in terms of reducing severe hypoglycaemia. In the whole group of patients, the reduction in HbA1c is transient and disappears after 5 years.


Subject(s)
Blood Glucose/drug effects , Diabetes Mellitus, Type 1/drug therapy , Hypoglycemia/prevention & control , Insulin Infusion Systems , Insulin/administration & dosage , Adult , Blood Glucose/metabolism , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/complications , Female , Follow-Up Studies , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
12.
Nat Commun ; 6: 8196, 2015 Sep 04.
Article in English | MEDLINE | ID: mdl-26337838

ABSTRACT

Advances in nanoscale magnetism increasingly require characterization tools providing detailed descriptions of magnetic configurations. Magnetic transmission X-ray microscopy produces element specific magnetic domain images with nanometric lateral resolution in films up to ∼100 nm thick. Here we present an imaging method using the angular dependence of magnetic contrast in a series of high resolution transmission X-ray microscopy images to obtain quantitative descriptions of the magnetization (canting angles relative to surface normal and sense). This method is applied to 55-120 nm thick ferromagnetic NdCo5 layers (canting angles between 65° and 22°), and to a NdCo5 film covered with permalloy. Interestingly, permalloy induces a 43° rotation of Co magnetization towards surface normal. Our method allows identifying complex topological defects (merons or ½ skyrmions) in a NdCo5 film that are only partially replicated by the permalloy overlayer. These results open possibilities for the characterization of deeply buried magnetic topological defects, nanostructures and devices.

13.
Nanotechnology ; 25(33): 335704, 2014 Aug 22.
Article in English | MEDLINE | ID: mdl-25074483

ABSTRACT

Strong asymmetries have been observed in grazing incidence small angle x-ray scattering (GISAXS) in situ patterns obtained from 30 nm-thick nanocrystalline Co films prepared by oblique sputtering (15°-75° off-sample normal). These asymmetries have been qualitatively simulated by a simple model consisting of an ensemble of 8 nm-wide inclined Co nanocolumns. It is found that narrow inclined features appear in the diffuse background resembling those characteristic of faceted systems, which can be used to obtain straightforward non-destructive estimations of buried nanocolumnar grains inclination, even for oblique angles below 45°, when the stronger and broader asymmetric features of the pattern are not yet fully formed. Furthermore, using magneto-optical microscopy, a marked change in the magnetic domain's nucleation and growth process has been observed in the sample prepared at 75°, with the stronger GISAXS asymmetries. Easy axis magnetization reversal starts by a random and homogeneous nucleation of small (∼µm) elongated domains aligned with the nanocolumn's long axis and proceeds through the preferred propagation of head-to-head domain walls (DWs) along the applied field direction. This peculiar magnetic behavior indicates that the strongly anisotropic nanostructuring created by the oblique growth process is equivalent, from a magnetic point of view, to an array of self-assembled buried nanowires. These results show how GISAXS and magneto-optical microscopy can be combined as a powerful tool for correlating the morphology and magnetism of thin nanostructured systems.

14.
J Phys Condens Matter ; 25(42): 426002, 2013 Oct 23.
Article in English | MEDLINE | ID: mdl-24067564

ABSTRACT

We have measured a negative thermal expansion (NTE) of the Co subnetwork in amorphous Nd1-xCox (0.78 < x < 0.84) thin films of the order of 1% in volume using linearly polarized EXAFS spectroscopy at RT and 10 K. The expansion, which is anisotropic, is uncorrelated with the perpendicular magnetic anisotropy (PMA) observed in all the films, but correlated with the method used to deposit them. The atomic environments of the Nd atoms resulted in such a strong disorder that Nd-Nd and Nd-Co environments were invisible to EXAFS, and only Co-Co atomic environments were detected. The information on the Nd subnetwork was obtained through its magnetic moment measured by XMCD. These measurements demonstrate an increasing interaction of neodymium atoms with their particular local crystal field as the temperature decreased, suggesting possible structural modifications at their sites. Since the magnetic moment of the cobalt subnetwork remains essentially constant with the temperature, it is proposed that its detected NTE may be caused by the mechanical response of the amorphous network to structural transformations at the Nd sites. These results support that the PMA in RE-TM alloys is localized at the RE sites. The complete absence of EXAFS oscillations in the Nd L3 EXAFS spectra is remarkable: it means that the coherence length of the photoemitted electrons in disordered matter can be strongly reduced from that expected by atomic calculations to the point of being less than first neighbor distances, which is contrary to the common belief that first neighbors are always visible by EXAFS.

15.
Anal Bioanal Chem ; 403(8): 2437-48, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22160236

ABSTRACT

Direct solid analysis of ultrathin layers is investigated using pulsed radiofrequency (rf) glow discharge (GD) time-of-flight mass spectrometry (TOFMS). In particular, previous studies have always integrated the detected ion signals in the afterglow region of the rf-GD pulse, which is known to be the most sensitive one. Nevertheless, the analytical capabilities of other pulse time regions have not been evaluated in detail. Therefore, in this work, we investigate the analyte prepeak region, which is the pulse region where the analyte ions peak after the initial sputtering process of each GD pulse, aiming at obtaining improved depth profile analysis with high depth resolution and with minimum polyatomic spectral interferences. To perform these studies, challenging ultrathin Si-Co bilayers deposited on a Si substrate were investigated. The thickness of the external Si layer was 30 nm for all the samples, whilst the internal Co layer thicknesses were 30, 10, 5, 2 and 1 nm, respectively. It should be remarked that the top layer and the substrate have the same matrix composition (Si > 99.99%). Therefore, the selected samples are suitable to evaluate the response of the Si ion signal in the presence of an ultrathin Co layer as well as the possible oxygen contaminations or its reactions. Additionally, these samples have been evaluated using time-of-flight secondary ion mass spectrometry, and the results compare well to those obtained by our pulsed rf-GD time-of-flight mass spectrometry results.

16.
Anal Bioanal Chem ; 396(8): 2881-7, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20082068

ABSTRACT

Nanometer depth resolution is investigated using an innovative pulsed-radiofrequency glow discharge time-of-flight mass spectrometer (pulsed-rf-GD-TOFMS). A series of ultra-thin (in nanometers approximately) Al/Nb bilayers, deposited on Si wafers by dc-magnetron sputtering, is analyzed. An Al layer is first deposited on the Si substrate with controlled and different values of the layer thickness, t(Al). Samples with t(Al) = 50, 20, 5, 2, and 1 nm have been prepared. Then, a Nb layer is deposited on top of the Al one, with a thickness t(Nb) = 50 nm that is kept constant along the whole series. Qualitative depth profiles of those layered sandwich-type samples are determined using our pulsed-rf-GD-TOFMS set-up, which demonstrated to be able to detect and measure ultra-thin layers (even of 1 nm). Moreover, Gaussian fitting of the internal Al layer depth profile is used here to obtain a calibration curve, allowing thickness estimation of such nanometer layers. In addition, the useful yield (estimation of the number of detected ions per sputtered atom) of the employed pulsed-rf-GD-TOFMS system is evaluated for Al at the selected operating conditions, which are optimized for the in-depth profile analysis with high depth resolution.

17.
J Phys Condens Matter ; 21(13): 134011, 2009 Apr 01.
Article in English | MEDLINE | ID: mdl-21817486

ABSTRACT

The application of genetic algorithms to the analysis of surface x-ray diffraction data is discussed and the implementation of a genetic algorithm of evolutionary type is described in detail. The structure of Sn/Cu(100)-[Formula: see text] is determined on the basis of surface x-ray diffraction data analysed using this algorithm. The results are compared to previous findings using other techniques.

18.
J Phys Condens Matter ; 21(22): 224024, 2009 Jun 03.
Article in English | MEDLINE | ID: mdl-21715762

ABSTRACT

Ion beam irradiation has been shown to be an interesting tool for tailoring the magnetic properties of thin films and multilayers. The modified properties include magnetic anisotropy, interlayer exchange coupling, exchange bias, magnetic domain structure and magnetization reversal. In this work, new results are shown concerning the enhancement, by one order of magnitude, of the antiferromagnetic coupling strength in amorphous CoSi/Si multilayers by irradiating Si(100) substrates with 1 keV Ar(+) ions. The ion beam exposure induces an increase of the substrate roughness, from 0.07 to 0.88 nm, which enhances antiferromagnetic coupling in the magnetic multilayers grown on top. One possible mechanism governing this enhancement is discussed, related to the formation of magnetic/non-magnetic regions where dipolar interactions could stabilize the antiferromagnetic alignment. The presence of non-magnetic regions is suggested by the observed trend to superparamagnetism, and is expected since the Curie temperature of the amorphous CoSi alloy used is slightly above but very close to room temperature. Accordingly, small fluctuations in the local composition, leading to an enrichment of Si, would produce non-magnetic regions enabling dipolar interactions to take place. Furthermore, the ion beam induced increase of roughness makes surface diffusion of the atoms arriving at the sample difficult, favoring the formation of local non-magnetic inhomogeneities. Finally, the role of other possible mechanisms to enhance antiferromagnetic coupling is also briefly discussed.

19.
Arch Soc Esp Oftalmol ; 83(5): 317-20, 2008 May.
Article in Spanish | MEDLINE | ID: mdl-18464181

ABSTRACT

PURPOSE/METHOD: To report the ophthalmologic presentation of two cases of esthesioneuroblastoma (ENB). A comprehensive ophthalmic assessment was made, including magnetic resonance imaging. A paranasal sinus mass was biopsied in one case and a nasal mass biopsied in the other. CASES REPORT/DISCUSSION: Two women, aged 85 and 32 years respectively, presented to the emergency room with ophthalmic symptoms and signs. The first reported orbital pain and eyelid edema and the second, who was 22 weeks pregnant, reported a spontaneous lower eyelid haematoma, orbital pain and rhinorrhoea. ENB is a rare malignant tumour and its presentation with ophthalmologic symptoms and signs is very infrequent.


Subject(s)
Esthesioneuroblastoma, Olfactory/complications , Nasal Cavity , Nose Neoplasms/complications , Adult , Aged, 80 and over , Esthesioneuroblastoma, Olfactory/diagnosis , Female , Humans , Nose Neoplasms/diagnosis
20.
Arch. Soc. Esp. Oftalmol ; 83(5): 317-320, mayo 2008. ilus
Article in Es | IBECS | ID: ibc-64538

ABSTRACT

Objetivo/Método: Presentar el debut de dos casos de estesioneuroblastoma (ENB) con manifestaciones oftalmológicas. Se realizó una exploración oftalmológica completa y estudios de imagen consistentes de Resonancia Magnética (RM). En un caso se realizó biopsia de una masa sinusal y en el otro de una masa nasal. Caso clínico/Discusión: Dos mujeres de 85 y 32 años, esta última embarazada de 21 semanas, acudieron de urgencia por síntomas y signos oculares. El primer caso refería dolor orbitario y edema de párpado y el segundo hematoma palpebral inferior espontáneo, dolor orbitario y rinorrea. El ENB es un tumor maligno poco frecuente que puede debutar con sintomatología oftalmológica


Purpose/Method: To report the ophthalmologic presentation of two cases of esthesioneuroblastoma (ENB). A comprehensive ophthalmic assessment was made, including magnetic resonance imaging. A paranasal sinus mass was biopsied in one case and a nasal mass biopsied in the other. Cases Report/Discussion: Two women, aged 85 and 32 years respectively, presented to the emergency room with ophthalmic symptoms and signs. The first reported orbital pain and eyelid edema and the second, who was 22 weeks pregnant, reported a spontaneous lower eyelid haematoma, orbital pain and rhinorrhoea. ENB is a rare malignant tumour and its presentation with ophthalmologic symptoms and signs is very infrequent (Arch Soc Esp Oftalmol 2008; 83: 317-320)


Subject(s)
Humans , Female , Adult , Aged , Neuroblastoma/diagnosis , Esthesioneuroblastoma, Olfactory/complications , Esthesioneuroblastoma, Olfactory/diagnosis , Triamcinolone/therapeutic use , Biopsy/methods , Nasal Obstruction/complications , Epistaxis/complications , Epistaxis/diagnosis , Eye Neoplasms/diagnosis , Eye Neoplasms/epidemiology , Neuroblastoma/pathology , Neuroblastoma/complications , Nasal Obstruction/diagnosis , Neuroblastoma , Esthesioneuroblastoma, Olfactory/therapy , Esthesioneuroblastoma, Olfactory , Paralysis/complications
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