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1.
ACS Omega ; 8(37): 33639-33650, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37744818

RESUMO

Heterostructured photocatalytic materials in the form of photonic crystals have been attracting attention for their unique light harvesting ability that can be ideally combined with judicious compositional modifications toward the development of visible light-activated (VLA) photonic catalysts, though practical environmental applications, such as the degradation of pharmaceutical emerging contaminants, have been rarely reported. Herein, heterostructured MoS2-TiO2 inverse opal films are introduced as highly active immobilized photocatalysts for the VLA degradation of tetracycline and ciprofloxacin broad-spectrum antibiotics as well as salicylic acid. A single-step co-assembly method was implemented for the challenging incorporation of MoS2 nanosheets into the nanocrystalline inverse opal walls. Compositional tuning and photonic band gap engineering of the MoS2-TiO2 photonic films showed that integration of low amounts of MoS2 nanosheets in the inverse opal framework maintains intact the periodic macropore structure and enhances the available surface area, resulting in efficient VLA antibiotic degradation far beyond the performance of benchmark TiO2 films. The combination of broadband MoS2 visible light absorption and photonic-assisted light trapping together with the enhanced charge separation that enables the generation of reactive oxygen species via firm interfacial coupling between MoS2 nanosheets and TiO2 nanoparticles is concluded as a competent approach for pharmaceutical abatement in water bodies.

2.
Front Psychol ; 11: 576070, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33551902

RESUMO

Future mobility planning to cope with ongoing environmental challenges such as air pollution has to be anchored in the work of every public authority worldwide. One recent trend that could support public authorities to meet the European Union's sustainability targets is the creation and sharing of transport and mobility "big" data between public authorities via tools such as crowdsourcing. While the benefits of the use of big data to increase public authorities' efficiency and effectivity and their citizens' lives is well understood, examples from the public sector that highlight public authorities' engagement in such sharing activities is still missing. To date relevant literature has highlighted issues around the capacity of public authorities that hinder shared activities. In this paper we want to raise distrust as a key reason for lack of engagement. Based on comprehensive data collected over the period of 4 years via several workshops and semi-structured interviews with seven public authorities in Europe, we are able to demonstrate that a major obstacle for not providing and sharing data via crowdsourcing for mutual benefit lies primarily in the hands of the public authority's servants of the middle and high-level management. Our results show firstly, that distrust may emerge toward different referents such as the community, particular individuals, or the technology itself and thus, managerial implications have to be very specific to overcome distrust. Secondly, we show how distrust may spread from one referent to another through negative reciprocity and which, if unchecked may lead to an all-encompassing state that affects the whole sharing economy framework and inhibits potential benefits.

3.
Br J Ophthalmol ; 98(5): 586-91, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24407561

RESUMO

BACKGROUND: To assess prevalence and causes of vision impairment in Southeast Asia and Oceania in 1990 and 2010. METHODS: Based on a systematic review of medical literature, prevalence of moderate and severe vision impairment (MSVI; presenting visual acuity <6/18 but ≥3/60 in the better eye) and blindness (presenting visual acuity <3/60) was estimated for 1990 and 2010. RESULTS: In Oceania, the age-standardised prevalence of blindness and MSVI did not decrease significantly (1.3% to 0.8% and 6.6% to 5.1%) respectively, but in Southeast Asia, blindness decreased significantly from 1.4% to 0.8%, a 43% decrease. There were significantly more women blind (2.18 million) compared with men (1.28 million) in the Southeast Asian population in 2010, but no significant gender differences in MSVI in either subregion. Cataract was the most frequent cause of blindness in Southeast Asia and Oceania in 1990 and 2010. Uncorrected refractive error, followed by cataract, macular degeneration, glaucoma and diabetic retinopathy were the most common causes for MSVI in 1990 and 2010. With the increasing size of the older population, there have been relatively small increases in the number of blind (2%), and with MSVI (14%) in Southeast Asia, whereas increases have been greater in Oceania of 14% for blindness and of 31% for MSVI. CONCLUSIONS: The prevalence of blindness has reduced significantly from 1990 to 2010, with moderate but non-significant lowering of MSVI. Cataract and uncorrected refractive error are the main causes of vision impairment and blindness; cataract continues as the main cause of blindness, but at lower proportions.


Assuntos
Povo Asiático/estatística & dados numéricos , Cegueira/etnologia , Cegueira/etiologia , Oftalmopatias/complicações , Oftalmopatias/etnologia , Havaiano Nativo ou Outro Ilhéu do Pacífico/estatística & dados numéricos , Sudeste Asiático/epidemiologia , Humanos , Oceania/epidemiologia , Prevalência
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 81(5 Pt 1): 051136, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20866214

RESUMO

We investigate the quantum transmission through laterally driven single- and double-barrier systems in the nonlinear regime of strong driving. A broad parameter range is explored, distinguishing in particular between different frequency regimes. The applicability of an effective, time independent, potential description in the high-frequency regime is explored. Moreover, we analyze in detail the inelastic processes and their dependence on parameters, resonant tunneling, and photon assisted tunneling. For the single-barrier problem we address driving laws that differ from the purely sinusoidal one. In this context, we encounter reduced spatial and temporal symmetries and demonstrate the corresponding effects on quantum pumping. For the double barrier, the focus of our studies lies on the impact of the variation in the relative phase of the barriers on the transmission.

5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 82(1 Pt 2): 016206, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20866706

RESUMO

We demonstrated very recently [Lenz, New J. Phys. 11, 083035 (2009)] that an ensemble of particles in the driven elliptical billiard shows a surprising crossover from subdiffusion to normal diffusion in momentum space. This crossover is not parameter induced, but rather occurs dynamically in the evolution of the ensemble. In this work, we consider three different driving modes of the elliptical billiard and perform a comprehensive analysis of the corresponding four-dimensional phase space. The composition of this phase space is different in the high-velocity regime compared to the low-velocity regime. We will show, among others, by investigating periodic orbits and probability distributions of laminar phases that the stickiness properties, which eventually determine the diffusion, are intimately connected with this change in the composition of the phase space with respect to velocity. In the course of the evolution, the accelerating ensemble thus explores regions of varying stickiness, leading to the mentioned crossover in the diffusion.

6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 81(4 Pt 2): 046219, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20481819

RESUMO

We explore the dynamics of noninteracting particles loaded into a phase-modulated one-dimensional lattice formed by laterally oscillating square barriers. Tuning the parameters of the driven unit cell of the lattice selected parts of the classical phase space can be manipulated in a controllable manner. We find superdiffusion in position space for all parameters regimes. A directed current of an ensemble of particles can be created through locally breaking the spatiotemporal symmetries of the time-driven potential. Magnitude and direction of the current are tunable. Several mechanisms for transient localization and trapping of particles in different wells of the driven unit cell are presented and analyzed.

7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 82(3 Pt 2): 035204, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21230130

RESUMO

We develop and analyze a scheme to achieve both spatial and energetic focusing of an ensemble of neutral particles which is based on an oscillating billiard with frictional forces. The interplay of two competing mechanisms, acceleration due to collisions with the oscillating billiard walls and deceleration caused by friction, leads to the emergence of attractors in phase space. Their specific properties, i.e., spatial localization and energy spread, can be controlled and tuned by varying, e.g., the frequency of the time-dependent billiard.

8.
Int J Cardiol ; 135(3): 361-9, 2009 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-18640731

RESUMO

BACKGROUND: Although there is evidence that inflammation and oxidative stress might contribute to the pathogenesis of atrial fibrillation (AF), the predictive value of inflammatory and oxidative stress markers in patients with AF has not been fully assessed. The aim of this study is to evaluate these markers as predictors of sinus rhythm (SR) maintenance, in patients with persistent lone AF. METHODS: Among 268 patients with symptomatic AF, we studied 46 patients with a first episode of recently established persistent lone AF. We measured the circulating levels of hs-CRP, TNF-alpha, IL-6, IL-10, sICAM-1, sVCAM-1, malondialdehyde (MDA) and nitrotyrosine (NT) before, 1 h, 24 h, 1, 2, 4 and 6 weeks after cardioversion. During a 12-month follow-up period, AF recurrence was evaluated by Holter ECG recordings every month and when symptoms were reported. RESULTS: Baseline levels of CRP, TNF-alpha, sICAM-1, MDA, and NT were elevated in patients with AF compared to controls, and higher in patients with than in those without persistent AF recurrence, while IL-6 levels were equally elevated in the two subgroups. SR maintenance was associated with lower baseline MDA values and faster decrease in IL-6, sICAM-1 and NT levels within the first 2 weeks following SR restoration. CONCLUSIONS: Increased markers of inflammation and oxidative stress are found in patients with lone AF, implying that inflammation and oxidative stress may be associated with the presence of the arrhythmia. IL-6, sICAM-1, MDA and NT, assessed prior to and after the first cardioverted episode of persistent arrhythmia, appear to be reliable, early predictors of SR maintenance during the following year.


Assuntos
Fibrilação Atrial/metabolismo , Fibrilação Atrial/patologia , Cardioversão Elétrica , Mediadores da Inflamação/sangue , Estresse Oxidativo/fisiologia , Adulto , Fibrilação Atrial/terapia , Biomarcadores/sangue , Estudos de Coortes , Feminino , Seguimentos , Humanos , Mediadores da Inflamação/fisiologia , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Resultado do Tratamento
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(6 Pt 2): 066213, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18233910

RESUMO

In this work we study the nonlinear dynamics of the static and the driven ellipse. In the static case, we find numerically an asymptotical algebraic decay for the escape of an ensemble of noninteracting particles through a small hole due to the integrable structure of the phase space of the system. Furthermore, for a certain hole position, a saturation value in the decay that can be tuned arbitrarily by varying the eccentricity of the ellipse is observed and explained. When harmonic boundary oscillations are applied, this saturation value, caused by librator-type orbits, is gradually destroyed via two fundamental processes which are discussed in detail. As a result, an amplitude-dependent emission rate is obtained in the long-time behavior of the decay, suggesting that the driven elliptical billiard can be used as a controllable source of particles.

10.
Echocardiography ; 23(2): 114-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16445728

RESUMO

OBJECTIVE: To assess by tissue Doppler echocardiography (TDE), the tissue velocities, both at rest and after exercise stress testing, in subjects with mitral valve prolapse (MVP) and those with thick mitral valve (TMV). METHODS: Twenty individuals with typical MVP, 30 with TMV, and 30 healthy controls were enrolled. TDE was performed at the basal-inferior wall and the parameters evaluated were the S, Em, and Am velocities, as well as the Em/Am ratio. RESULTS: The mean S-wave at rest was higher in subjects with MVP compared to that of the TMV (P < 0.01) and the control groups (P = 0.00005), whereas after exercise it was higher in the control group compared to either MVP (P = 0.013) or TMV group (P = 0.00002). The mean Em wave at rest was higher in the control individuals both at rest (P = 0.007 compared with MVP group and P = 0.013 compared with TMV group), and after exercise (P = 0.0002 and 0.0009, respectively). The Am wave in the MVP group was higher compared with TMV and control subjects at rest (P = 0.022 and 0.00001, respectively) but it was not after exercise (P = ns for both comparisons). The Em/Am ratio of the control group at rest was higher than that of the MVP (P = 0.0000) and TMV (P = 0.00028) groups. However, after exercise, it was higher only when compared with the MVP group (P = 0.016). CONCLUSIONS: Subjects with MVP and those with TMV exhibit a less effective contractile response to exercise compared to healthy individuals. Some degree of diastolic dysfunction, particularly after exercise, was also detected in the individuals with MVP.


Assuntos
Ecocardiografia Doppler , Prolapso da Valva Mitral/diagnóstico por imagem , Prolapso da Valva Mitral/fisiopatologia , Adulto , Idoso , Análise de Variância , Estudos de Casos e Controles , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiopatologia , Contração Miocárdica
11.
Hellenic J Cardiol ; 47(6): 344-51, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17243506

RESUMO

INTRODUCTION: Brain natriuretic peptide (BNP) correlates well with left ventricular wall hypertrophy and the severity of left ventricular outflow tract (LVOT) obstruction in patients with hypertrophic cardiomyopathy (HCM). The purpose of this study was to investigate the correlation of BNP levels with clinical status and left ventricular function in HCM patients. METHODS: In 32 patients with HCM (age 58 +/- 14 years) we evaluated: (a) the severity of dyspnea and angina; (b) BNP plasma levels; (c) left ventricular wall thickness, sphericity index and mitral regurgitation; (d) LVOT obstruction; (e) ejection fraction; (f) left ventricular diastolic function, global and regional, by tissue Doppler imaging. RESULTS: BNP plasma levels correlated positively with dyspnea (r = 0.460, p < 0.001), angina (r = 0.460, p = 0.008), mitral regurgitation (r = 0.600, p < 0.001), thickness of interventricular septum (r = 0.526, p = 0.002), and LVOT obstruction (r = 0.551, p = 0.001 and r = 0.603, p < 0.001 for latent obstruction), while they were negatively correlated with left ventricular sphericity index (r = -0.368, p = 0.038). BNP plasma levels were strongly correlated with E/Vp and E/Eal (Vp: flow propagation velocity, Eal: E on the lateral side of the mitral annulus), representing the left ventricular filling pressures, and with some other parameters of regional diastolic function: Ams (A at the mid-segment of the interventricular septum) r = -0.518, p = 0.002; Aas (A on the septal side of the mitral annulus) r = -0.454, p = 0.009; Aal (A on the lateral side of the mitral annulus) r = -0.467, p = 0.007. From multiple regression analysis, angina and the ratio E/Eal were the strongest predictors of BNP plasma levels. CONCLUSIONS: BNP plasma levels in HCM patients can be used as an adjunctive objective method of evaluating cardiac dysfunction through their correlation with angina and left ventricular filling pressures.


Assuntos
Cardiomiopatia Hipertrófica/sangue , Peptídeo Natriurético Encefálico/sangue , Disfunção Ventricular Esquerda/diagnóstico , Adulto , Idoso , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/fisiopatologia , Análise de Regressão , Sensibilidade e Especificidade , Ultrassonografia , Disfunção Ventricular Esquerda/fisiopatologia
13.
Clin Cardiol ; 25(2): 83-5, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11841156

RESUMO

A 19-year-old male presented with fever, substernal pain, dyspnea, and distended neck veins. Diagnostic investigations, such as echocardiography and magnetic resonance imaging, provided evidence of a large mass within the pericardial sac, attached by a broad base to the parietal pericardium and lying along the right ventricular free wall. A partial pericardiectomy was performed to relieve the patient's symptoms, and histologic examination of a biopsy specimen showed features of a malignant, spindle cell, mesenchymal neoplasm. The patient underwent surgical treatment during which the tumor was found to infiltrate the anterior surface of the right ventricle. Histologically, the tumor was identified as a high-grade fibrosarcoma, and additional chemotherapy was given.


Assuntos
Tamponamento Cardíaco/etiologia , Fibrossarcoma/diagnóstico , Neoplasias Cardíacas/diagnóstico , Pericárdio , Adulto , Tamponamento Cardíaco/diagnóstico , Diagnóstico Diferencial , Fibrossarcoma/complicações , Fibrossarcoma/cirurgia , Neoplasias Cardíacas/complicações , Neoplasias Cardíacas/cirurgia , Humanos , Masculino , Pericárdio/patologia , Resultado do Tratamento
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