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1.
Artigo em Inglês | MEDLINE | ID: mdl-38972352

RESUMO

INTRODUCTION: Implantable pulse generator (IPG) is a neurostimulation therapy mediated by electrodes and surgically implanted in a subcutaneous "pocket" used for the control of numerous pathologies. This study examines both the prevalence of pain associated with IPG implantation ("pain pocket syndrome") and its associated characteristics. MATERIALS AND METHODS: 56 patients with an IPG were included in the study. A health questionnaire was conducted to determine the presence of pain associated with the pocket and its neuropathic characteristics, as well as associated aesthetic concerns, location, situations that accentuate or alleviate pain, medications used for baseline and pocket pain control and other factors associated. RESULTS: Pain in the area of implantation of the IPG had a prevalence of 52.6% of patients (n = 27), in our sample, with a mean score on the visual analogic scale (VAS) of 4.9 points [3.9-5.8 points], with neuropathic characteristics in 53.3% (n = 16) of the patients with pain, with differences between the mean VAS score of the female (5.5 [4.3-5.8 points]) and males (3.5 points [2.1-4.9 points]) (p = 0.04). CONCLUSION: Pocket pain is a condition with a higher prevalence than described in previous studies, being of a higher intensity in females, involving a moderate pain in the area of implantation of the neuromodulating therapy. This pain has neuropathic characteristics and could require a repositioning intervention. Hence, more studies in this field should be carried to detect and prevent this syndrome.

2.
Energy Fuels ; 38(11): 10038-10049, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38863685

RESUMO

A systematic study on the electrochemical reforming of monosaccharides (fructose, glucose, and xylose) using Pt-based anodic electrocatalysts is here presented for the first time to completely optimize the anodic catalyst and electrolyzer operating conditions. First, the electro-oxidation of each molecule was studied using a monometallic (Pt) and two bimetallic (PtNi and PtCo) anodic electrocatalysts supported on graphene nanoplatelets (GNPs). Tests in a three-electrode cell showed superior electrochemical activity and durability of PtNi/GNPs, especially at potentials higher than 1.2 V vs RHE, with the highest electrocatalytic activity in d-xylose electro-oxidation. Then, monometallic (Pt and Ni) and bimetallic electrocatalysts with different Pt:Ni mass ratios (1:1 and 2:1) were studied for d-xylose electro-oxidation, with the 2:1 mass ratio presenting the best results. This electrocatalyst was selected as the most suitable for scale-up to an anion-exchange membrane electrolyzer, where the optimal operating potential was determined. Additionally, stable operating conditions of the electrolyzer were achieved by cyclic H2 production and cathodic regeneration polarization steps. This led to suitable and reproducible H2 production rates throughout the production cycles for renewable hydrogen production from biomass-derived streams.

3.
Arch Soc Esp Oftalmol (Engl Ed) ; 99(8): 323-330, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38768852

RESUMO

OBJECTIVE: To carry out a methodologically complete validation of the Spanish version of the Keratoconus End-Points Assessment Questionnaire (KEPAQ) in a Spanish population with keratoconus. METHODS: Analytical, prospective study, including patients with keratoconus without previous surgical history, in which a measurement of quality of life was performed using the KEPAQ questionnaire, a complete exploration of the anterior pole and a corneal elevation topography with the Galilei G6 topographer. The evaluation of the psychometric characteristics of the scale in the studied population was carried out using Rasch modeling. RESULTS: A total of 140 patients with keratoconus were included, with a median age of 26.0 years, the majority (57.6%) being men. For the KEPAQ-E subscale, the median score was 69.3, with a reliability of 0.85 and an eigenvalue of the first contrast of 2.34. For the KEPAQ-F, the median score was 56.4, with a reliability of 0.88 and an eigenvalue of 2.00. All infit and outfit parameters were within normal limits for both subscales. A significant evaluation was found between the evaluations of both subscales (rho = 0.696; p < 0.001). The evaluations of the subscales and various clinical and tomographic characteristics showed a significant classification between them (p value between 0.048 y 0.001). CONCLUSION: The KEPAQ is a psychometrically robust and valid scale to evaluate quality of life in the Spanish population with keratoconus. This questionnaire can be easily used for both clinical and research aims.


Assuntos
Ceratocone , Qualidade de Vida , Ceratocone/diagnóstico , Humanos , Masculino , Feminino , Adulto , Estudos Prospectivos , Espanha , Adulto Jovem , Psicometria , Inquéritos e Questionários , Adolescente , Reprodutibilidade dos Testes , Pessoa de Meia-Idade , Topografia da Córnea
4.
Heliyon ; 9(10): e20748, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37876428

RESUMO

In this work, metal-free boron-doped graphene-based aerogels were successfully synthesized via a one-step autoclave assembly followed by freeze-drying and used as electrocatalysts for the hydrogen evolution reaction (HER) in acidic media. The synthesized reduced graphene oxide aerogels (rGOA) showed improved electrocatalytic activity by introducing boron and structural defects. The amount of boric acid used both as a dopant and reducing agent in the synthesis was optimized (boric acid/GO mass ratio = 17.5) to practically reach the crystallization limit of boric acid (boric acid/GO mass ratio = 20). It was observed that the higher the amount of boric acid added, the more boron was incorporated into the carbonaceous structure, improving the electrocatalytic activity of the final aerogel. Furthermore, calcination of the boron-doped electrocatalyst at 600 °C resulted in final aerogels with low oxygen content, moderate surface area, bimodal pore size distribution, and a high electrochemical active surface area. The final 3D graphene aerogel developed in this work, showed such outstanding electrocatalytic activity in HER as to replace noble metal-based electrocatalysts in the future.

5.
Appl Radiat Isot ; 200: 110913, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37442027

RESUMO

This paper describes a procedure for the validation of alpha-particle sources (exempt unsealed sources) to be used in experimental setups with liquefied gases at cryogenic temperatures (down to -196 °C) and high vacuum. These setups are of interest for the development and characterization of neutrino and dark matter detectors based on liquid argon, among others. Due to the high purity requirements, the sources have to withstand high vacuum and cryogenic temperatures for extended periods. The validation procedure has been applied to 241Am sources produced by electrodeposition.

6.
J Electr Bioimpedance ; 12(1): 3-10, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34413917

RESUMO

A portable electrical impedance spectroscopy device was developed to monitor the bioimpedance resistive component of bovine meat by injecting a sinusoidal current of 1 mA at 65 kHz. Both right and left longissimus dorsi muscles were trimmed from 4 slaughtered cows. The left muscle portions were frozen to -18 °C for 7 days while the right ones were meantime maintained at 5 °C. Mean value of impedance per length (Ω/cm) of frozen and thawed left samples was 31% lower than that of right non-frozen one (P = 0.0001). It was concluded that the device is reliable for monitoring the maturation of beef meat in situ with the possibility of revealing undeclared freeze-thaw cycles.

7.
Nature ; 520(7546): 209-11, 2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-25855457

RESUMO

The chemical properties of an element are primarily governed by the configuration of electrons in the valence shell. Relativistic effects influence the electronic structure of heavy elements in the sixth row of the periodic table, and these effects increase dramatically in the seventh row--including the actinides--even affecting ground-state configurations. Atomic s and p1/2 orbitals are stabilized by relativistic effects, whereas p3/2, d and f orbitals are destabilized, so that ground-state configurations of heavy elements may differ from those of lighter elements in the same group. The first ionization potential (IP1) is a measure of the energy required to remove one valence electron from a neutral atom, and is an atomic property that reflects the outermost electronic configuration. Precise and accurate experimental determination of IP1 gives information on the binding energy of valence electrons, and also, therefore, on the degree of relativistic stabilization. However, such measurements are hampered by the difficulty in obtaining the heaviest elements on scales of more than one atom at a time. Here we report that the experimentally obtained IP1 of the heaviest actinide, lawrencium (Lr, atomic number 103), is 4.96(+0.08)(-0.07) electronvolts. The IP1 of Lr was measured with (256)Lr (half-life 27 seconds) using an efficient surface ion-source and a radioisotope detection system coupled to a mass separator. The measured IP1 is in excellent agreement with the value of 4.963(15) electronvolts predicted here by state-of-the-art relativistic calculations. The present work provides a reliable benchmark for theoretical calculations and also opens the way for IP1 measurements of superheavy elements (that is, transactinides) on an atom-at-a-time scale.

8.
Radiologia ; 55(2): 142-7, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-22015223

RESUMO

OBJECTIVE: To determine whether the introduction of digital mammography in breast cancer screening has resulted in changes in the detection and management of microcalcifications. MATERIAL AND METHODS: We retrospectively studied the performance indicators of our breast cancer screening program that are related to the diagnosis of microcalcifications (rates of recall and recommendation of intermediate follow-up after screening, rate of indication of invasive procedures for microcalcifications and their positive predictive value, detection rate for microcalcifications, and number of ductal carcinomas in situ (DCIS) diagnosed). We compared the results obtained using direct digital mammography (september 2008-august 2009) with those obtained using analog mammography (September 2006-August 2007). STATISTICAL ANALYSIS: Chi-square test and measures of association. RESULTS: We found that using digital mammography led to significant increases in the recall rate (from 50.8 to 64‰), in the rate of intermediate follow-up after screening (from 9.41 to 18.7‰), in the rate of indication for invasive procedures (from 1.88 to 3.01‰), in the cancers detected through microcalcifications (from 0.86 to 1.36‰), and in the number of DCIS diagnosed. CONCLUSION: Direct digital mammography has improved the detection of microcalcifications, increasing the number of DCIS diagnosed without decreasing the positive predictive value of the invasive procedures indicated for microcalcifications. However, direct digital mammography has had a negative effect by increasing the recall rate and indication for short-term follow-up, possibly due to the difficulty of comparing the findings with those of earlier analog mammograms.


Assuntos
Doenças Mamárias/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Detecção Precoce de Câncer , Mamografia/métodos , Intensificação de Imagem Radiográfica , Doenças Mamárias/terapia , Neoplasias da Mama/complicações , Calcinose/complicações , Calcinose/terapia , Carcinoma Intraductal não Infiltrante/complicações , Feminino , Humanos , Estudos Retrospectivos
9.
Rev Sci Instrum ; 83(2): 02A910, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22380251

RESUMO

We investigated the ion-loss distribution on the sidewall of an electron cyclotron resonance (ECR) plasma chamber using the 18-GHz ECR charge breeder at the Tokai Radioactive Ion Accelerator Complex (TRIAC). Similarities and differences between the ion-loss distributions (longitudinal and azimuthal) of different ion species (i.e., radioactive (111)In(1+) and (140)Xe(1+) ions that are typical volatile and nonvolatile elements) was qualitatively discussed to understand the element dependence of the charge breeding efficiency. Especially, the similarities represent universal ion loss characteristics in an ECR charge breeder, which are different from the loss patterns of electrons on the ECRIS wall.

10.
Rev Sci Instrum ; 82(3): 033508, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21456738

RESUMO

The ion loss distribution in an electron cyclotron resonance ion source (ECRIS) was investigated to understand the element dependence of the charge breeding efficiency in an electron cyclotron resonance (ECR) charge breeder. The radioactive (111)In(1+) and (140)Xe(1+) ions (typical nonvolatile and volatile elements, respectively) were injected into the ECR charge breeder at the Tokai Radioactive Ion Accelerator Complex to breed their charge states. Their respective residual activities on the sidewall of the cylindrical plasma chamber of the source were measured after charge breeding as functions of the azimuthal angle and longitudinal position and two-dimensional distributions of ions lost during charge breeding in the ECRIS were obtained. These distributions had different azimuthal symmetries. The origins of these different azimuthal symmetries are qualitatively discussed by analyzing the differences and similarities in the observed wall-loss patterns. The implications for improving the charge breeding efficiencies of nonvolatile elements in ECR charge breeders are described. The similarities represent universal ion loss characteristics in an ECR charge breeder, which are different from the loss patterns of electrons on the ECRIS wall.

11.
Rev Sci Instrum ; 81(2): 02A902, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20192400

RESUMO

We have developed a new ion source system in the isotope separator on-line at Japan Atomic Energy Agency, for separation of short-lived isotopes produced by proton-induced fission of (238)U. The ion source system is a forced electron beam induced arc discharge version E type ion source with a target container. We successfully operated this system at 2000 degrees C as a result of reductions in volume of the ion source and the target container, introduction of heating method by electron bombardment, and improvement to the heat shield. This new ion source system was tested using (238)U of 640 mg/cm(2) with a proton primary beam of 30 MeV, 350 nA. Release times were measured for Kr, In, and Xe. The values of release times are 2.6 s for Kr, 1.8 s for In, and 4.6 s for Xe. In this work, the ion source system enabled us to mass-separate short-lived isotopes such as (93)Kr(T(1/2)=1.286 s), (129)In(T(1/2)=0.61 s), and (141)Xe(T(1/2)=1.73 s) with intensity of 10(3) ions/s.

12.
Rev Sci Instrum ; 79(2 Pt 2): 02A906, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18315161

RESUMO

The KEKCB is an electron cyclotron resonance (ECR) ion source for converting singly charged ions to multicharged ones at Tokai Radioactive Ion Accelerator Complex. By using the KEKCB, singly charged gaseous and nongaseous ions were converted to multicharged ones of A/q approximately 7 with efficiencies of 7% and 2%, respectively. The conversion efficiency was found to be independent of the lifetime of the radioactive nuclei having lifetimes of the order of one second. Three collimators located at the entrance and the exit of the KEKCB defined the beam axis and facilitated beam injection. Grinding and washing the surfaces of aluminum electrode and plasma chamber dramatically reduced impurities originating from the ECR plasma of the KEKCB.

14.
Transplant Proc ; 38(8): 2534-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17097992

RESUMO

BACKGROUND: Brain naturietic peptide (BNP) elevations have been reported in heart transplant patients both at baseline and during rejection. An association between BNP levels and certain echocardiographic and hemodynamic abnormalities has also been found in nontransplanted heart disease patients. We sought to determine whether BNP values were correlated with echocardiographic and hemodynamic parameters among a large cohort of heart transplant patients. MATERIALS AND METHODS: We studied 71 consecutive heart transplant patients, excluding combined grafts, retransplants, and pediatric cases. We performed 488 BNP determinations during catheterization and within 48 hours of echocardiography. Hemodynamic parameters included mean pulmonary artery pressure, right ventricular systolic and diastolic pressures. Doppler echocardiography parameters were wall thickness, ventricular mass, left and right ventricular end-diastolic and end-systolic diameters, isovolumic relaxation time, and mitral flow deceleration time. RESULTS: We observed significant correlations between BNP values and left ventricular size, ventricular mass, and a restrictive filling pattern. BNP levels were also significantly correlated with right ventricular size, mean pulmonary artery pressure, and right ventricular diastolic and end-diastolic pressures. CONCLUSIONS: In heart transplant patients, BNP levels positively correlated with ventricular diameters and a restrictive filling pattern. An increase in right ventricle and pulmonary artery pressures was associated with elevated BNP values.


Assuntos
Pressão Sanguínea , Transplante de Coração/fisiologia , Peptídeo Natriurético Encefálico/sangue , Biomarcadores/sangue , Eletrocardiografia , Humanos , Seleção de Pacientes
15.
Transplant Proc ; 38(8): 2575-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17098007

RESUMO

AIM: To undertake an evolutionary analysis of echocardiographic examinations carried out during follow-up of cardiac transplant patients. MATERIALS AND METHODS: The study included 193 consecutive patients transplanted between August 1998 and December 2004. We excluded pediatric, cardiopulmonary, and repeat transplants. Four echocardiographic examinations were analyzed per patient (first, second, third quarter and the last study carried out; average time from transplant: 1115 +/- 681 days). The total number of examinations was 772. The evaluated variables were thickness of walls and diameters of the cavities, systolic and diastolic functions, pericardial effusion, and number of rejections. RESULTS: The isovolumetric relaxation time showed reduced values during early echocardiography with subsequent increases during evolution (first echocardiogram: 92 +/- 16 vs final echocardiogram 101 +/- 16 ms; P < .0001). Right ventricular function showed initial deterioration with subsequent recovery (first echocardiogram: 16% vs final echocardiogram: 8%; P < .05); moreover, the existence of delayed malfunction of the right ventricle was correlated with a higher incidence of transplant rejection (P < .01). Pericardial effusion was initially present with a tendency to reduce over time (first echocardiogram: 58% vs final echocardiogram: 12%; P < .0001). There was no difference in the other variables. CONCLUSIONS: Cardiac transplant patients undergo evolutionary echocardiogram alterations that were mainly early and normalized as of the first quarter. The most usual changes in this period were restrictive isovolumetric behavior accompanied by some degree of depressed right ventricular function. Right ventricular malfunction during late evolution was correlated with a higher incidence of transplant rejection during follow-up.


Assuntos
Eletrocardiografia , Transplante de Coração/fisiologia , Rejeição de Enxerto/diagnóstico por imagem , Seleção de Pacientes , Pericárdio/diagnóstico por imagem , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia , Vasodilatação
16.
Rev Neurol ; 43 Suppl 1: S71-81, 2006 Oct 10.
Artigo em Espanhol | MEDLINE | ID: mdl-17061200

RESUMO

AIMS: The aim of this study is to report on the neuropsychological aspects of teenage patients with attention deficit hyperactivity disorder (ADHD), namely disorders affecting attention, memory, the executive functions and language. We also discuss how to perform neuropsychological and functional evaluation of the systems involved in attention, by means of haemodynamic (functional magnetic resonance imaging) and neurophysiological (magnetoencephalography) techniques. The comorbidities that most frequently occur in teenage patients with ADHD are also described. DEVELOPMENT: The fundamental symptoms, that is to say, inattention, hyperactivity and impulsiveness, continue to be present in the teenager with ADHD, although with mild variations, and are probably dependent on each individual's own genetic load. The disorders most commonly associated with ADHD are oppositional defiant disorder (33%), conduct disorders (25%), anxiety (25%), learning disabilities (22%) and depression (22%). CONCLUSIONS: During adolescence, patients with ADHD usually suffer disorders that are secondary to their inability to process information efficiently due to the inadequate development of the executive functions. The lack of inhibitory control and a poor capacity to learn from their own mistakes facilitate the appearance of comorbid neuropsychiatric disorders.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtornos Mentais/etiologia , Doenças do Sistema Nervoso/etiologia , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Humanos , Deficiências da Aprendizagem/etiologia , Magnetoencefalografia , Processos Mentais
17.
J Thromb Haemost ; 4(7): 1530-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16839350

RESUMO

BACKGROUND: Cardiovascular risk factors for myocardial infarction (MI) are less frequent in younger than in older MI survivors. Therefore, the thrombotic component of MI may play a more important role at a young age. As activated protein C (APC) provides systemic anticoagulant and anti-inflammatory protection, a low plasma APC level may be an arterial thrombotic risk factor. AIM: To determine whether there is an association between reduced APC levels and early MI and severe coronary lesions. METHODS: APC was measured in 231 young MI survivors and 231 controls. RESULTS: Low APC levels were significantly associated with MI. Compared with the fourth quartile, the odds ratio (OR) for APC values in the first quartile was 3.7 [95% confidence interval (CI) = 2.1-6.4], and 3.2 (1.5-7.0) after adjustment for cardiovascular risk factors. Moreover, each decrease of 0.43 ng mL(-1) (1 SD) in APC increased the OR 1.7 times (1.4-2.2), and 1.5 times (1.2-1.9) after adjustment for cardiovascular risk factors. Low APC levels were also associated with the number of coronary arteries affected and with the severity of coronary lesions (P < 0.001). CONCLUSIONS: There is a significant association between low circulating APC levels and both early MI and the extent and severity of coronary atherosclerosis, which might be related to the anticoagulant and anti-inflammatory properties of APC.


Assuntos
Doença da Artéria Coronariana/patologia , Infarto do Miocárdio/sangue , Proteína C/análise , Sobreviventes , Adulto , Fatores Etários , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco , Índice de Gravidade de Doença
18.
Appl Radiat Isot ; 64(7): 751-4, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16580839

RESUMO

The Cd concentration in food is a public concern related to the human health. In order to remove Cd-polluted food, the development and validation of a rapid and sensitive method of Cd analysis is required. By applying the multiple gamma-ray detection method to prompt gamma-ray analysis (PGA), the influence from nuclei which emit only one prompt gamma-ray at a time at every neutron capture reaction can be reduced, therefore the quantification limit of Cd is improved significantly. The limit of Cd contained in rice in the case of MPGA was evaluated, and under our proposed experimental conditions, it may be possible to quantify Cd content in rice to within 0.2 ppm in 10 min.


Assuntos
Cádmio/análise , Contaminação de Alimentos/análise , Oryza/química , Raios gama , Humanos , Análise Espectral/métodos
19.
Phys Rev Lett ; 95(10): 102502, 2005 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-16196924

RESUMO

alpha-gamma and alpha-electron coincidence spectroscopy for a short-lived heavy actinide nucleus (257)No (T(1/2) = 24.5 s) has been performed using a gas-jet transport system and an on-line isotope separator. Spin-parities of excited states in (253)Fm fed by the alpha decay of (257)No have been identified on the basis of the measured internal conversion coefficients. The nu3/2(+)[622] configuration has been assigned to the ground state of (257)No as well as to the 124.1 keV level in (253)Fm. It was found that the ground-state configuration of (257)No is different from that of lighter N = 155 isotones.

20.
Suppl Tumori ; 4(3): S155-6, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-16437962

RESUMO

The thyroid microcarcinoma is definited differentiated carcinoma of max 1 cm in diameter. We have reviewed clinical and histopathological results of 54 consecutive patients with papillary and follicular thyroid microcarcinoma and operated in the our clinic in the period 1985 to 2004. Several variables, such as older age, multifocality, bilateral disease, and extrathyroidal spread at initial assessment, may have some adverse prognostic significance. We recommend total thyroidectomy accompanied by modified neck dissection if enlarged nodes are diagnosed.


Assuntos
Carcinoma/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Adulto , Carcinoma/patologia , Feminino , Seguimentos , Humanos , Masculino , Neoplasias da Glândula Tireoide/patologia
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