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1.
Environ Res ; 247: 118120, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38199476

RESUMO

Photo-catalysts based on BiVO4 (BV) and Eco-graphene (EG) were synthesized and obtained in a single step with high-quality properties. These nanostructures (NEs) were obtained through a green chemistry route and by adding 2, 3, and 5 wt% of a homemade EG. The BV/X EG NEs (where X = corresponds to the weight % of EG) demonstrated high photocatalytic activity, obtaining Sulfamethoxazole degradation percentages of 40, 45, 52, and 57 for BV, BV/2 EG, BV/3 EG, and BV/5 EG respectively, using a blue LED light. In addition, it was observed that the presence of EG slightly affected the surface area and porosity of BV. Moreover, it was observed that the presence of EG stabilized the scheelite monoclinic phase (m-s), and decreased the crystal size and band-gap values of BV-based samples. It was detected that EG contents increased the BV reduction, creating oxygen vacancies and V4+ states, which favored electron transfer, enhanced the photo-catalytic activity, and decreased the recombination rate. The adsorption influence of the BV/EG system was also studied. Finally, the stability tests of these materials after four cycles of reuse allowed keeping practically the full degradation capacity, demonstrating that these NEs represent a promising material driven by visible light that can be used for wastewater decontamination in the presence of drugs.


Assuntos
Grafite , Nanoestruturas , Grafite/química , Sulfametoxazol , Adsorção , Luz
2.
Phys Rev Lett ; 130(19): 193601, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37243649

RESUMO

With a levitodynamics experiment in the strong and coherent quantum optomechanical coupling regime, we demonstrate that the oscillator acts as a broadband quantum spectrum analyzer. The asymmetry between positive and negative frequency branches in the displacement spectrum traces out the spectral features of the quantum fluctuations in the cavity field, which are thus explored over a wide spectral range. Moreover, in our two-dimensional mechanical system the quantum backaction, generated by such vacuum fluctuations, is strongly suppressed in a narrow spectral region due to a destructive interference in the overall susceptibility.

3.
J Environ Manage ; 299: 113452, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34526276

RESUMO

Cadiz Bay is a shallow mesotidal lagoon with extensive populations of the seagrass Cymodocea nodosa at intertidal and shallow subtidal elevations. This work aims to understand the mechanisms behind the resilience of this species to gradual sea level rise by studying its acclimation capacity to depth along the shallow littoral, and therefore, to gradual variations in the light environment. To address this objective, these populations have been monitored seasonally over a 10 year period, representing the longest seasonal database available in the literature for this species. The monitoring included populations at 0.4, -0.08 and -0.5 m LAT. The results show that C. nodosa has a strong seasonality for demographic and shoot dynamic properties - with longer shoots and larger growth in summer (high temperature) than in winter (low temperature), but also some losses. Moreover, shoots have different leaf morphometry depending on depth, with small and dense shoots in the intertidal areas (0.4 m) and sparse large shoots in the subtidal ones (-0.08 and 0.5 m). These differences in morphometry and shoot dynamic properties, combined with the differences in shoot density, explain the lack of differences in meadow production balance (i.e. meadow growth - meadow losses) between the intertidal (0.4 m) and the deepest population (-0.5 m), supporting the long term resilience of Cymodocea nodosa in Cadiz Bay. This study contributes to the understanding of the mechanisms behind seagrass stability and resilience, which is particularly important towards predicting the effects of climate change on these key coastal ecosystems, and also highlights the value of continuous long-term monitoring efforts to evaluate seagrass trajectories.


Assuntos
Alismatales , Ecossistema , Aclimatação , Mudança Climática , Folhas de Planta
4.
Osteoporos Int ; 31(10): 1935-1942, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32474650

RESUMO

FRAX® calculates the 10-year probability of major osteoporotic fractures (MOF), which are considered to have a greater clinical impact than other fractures. Our results suggest that, in postmenopausal women with severe osteoporosis, those treated with teriparatide had a 60% lower risk of FRAX®-defined MOF compared with those treated with risedronate. INTRODUCTION: The VERO trial was an active-controlled fracture endpoint clinical trial that enrolled postmenopausal women with severe osteoporosis. After 24 months, a 52% reduction in the hazard ratio (HR) of clinical fractures was reported in patients randomized to teriparatide compared with risedronate. We examined fracture results restricted to FRAX®-defined major osteoporotic fractures (MOF), which include clinical vertebral, hip, humerus, and forearm fractures. METHODS: In total, 1360 postmenopausal women (mean age 72.1 years) were randomized to receive subcutaneous daily teriparatide (20 µg) or oral weekly risedronate (35 mg). Patient cumulative incidence of ≥ 1 FRAX®-defined MOF and of all clinical fractures were estimated by Kaplan-Meier analyses, and the comparison between treatments was based on the stratified log-rank test. Additionally, an extended Cox model was used to estimate HRs at different time points. Incidence fracture rates were estimated at each 6-month interval. RESULTS: After 24 months, 16 (2.6%) patients in the teriparatide group had ≥ 1 low trauma FRAX®-defined MOF compared with 40 patients (6.4%) in the risedronate group (HR 0.40; 95% CI 0.23-0.68; p = 0.001). Clinical vertebral and radius fractures were the most frequent FRAX®-defined MOF sites. The largest difference in incidence rates of both FRAX®-defined MOF and all clinical fractures between treatments occurred during the 6- to 12-month period. There was a statistically significant reduction in fractures between groups as early as 7 months for both categories of clinical fractures analyzed. CONCLUSION: In postmenopausal women with severe osteoporosis, treatment with teriparatide was more efficacious than risedronate, with a 60% lower risk of FRAX®-defined MOF during the 24-month treatment period. Fracture risk was statistically significantly reduced at 7 months of treatment. CLINICAL TRIAL INFORMATION: ClinicalTrials.gov Identifier: NCT01709110 EudraCT Number: 2012-000123-41.


Assuntos
Conservadores da Densidade Óssea , Osteoporose Pós-Menopausa , Fraturas por Osteoporose , Idoso , Densidade Óssea , Conservadores da Densidade Óssea/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/prevenção & controle , Ácido Risedrônico/uso terapêutico , Teriparatida/uso terapêutico
5.
Phys Rev Lett ; 124(2): 023601, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-32004051

RESUMO

Recent optomechanical experiments have observed nonclassical properties in macroscopic mechanical oscillators. A key indicator of such properties is the asymmetry in the strength of the motional sidebands produced in the probe electromagnetic field, which is originated by the noncommutativity between the oscillator ladder operators. Here we extend the analysis to a squeezed state of an oscillator embedded in an optical cavity, produced by the parametric effect originated by a suitable combination of optical fields. The motional sidebands assume a peculiar shape, related to the modified system dynamics, with asymmetric features revealing and quantifying the quantum component of the squeezed oscillator motion.

6.
Phys Rev Lett ; 120(2): 020503, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29376724

RESUMO

The extraordinary sensitivity of the output field of an optical cavity to small quantum-scale displacements has led to breakthroughs such as the first detection of gravitational waves and of the motions of quantum ground-state cooled mechanical oscillators. While heterodyne detection of the output optical field of an optomechanical system exhibits asymmetries which provide a key signature that the mechanical oscillator has attained the quantum regime, important quantum correlations are lost. In turn, homodyning can detect quantum squeezing in an optical quadrature but loses the important sideband asymmetries. Here we introduce and experimentally demonstrate a new technique, subjecting the autocorrelators of the output current to filter functions, which restores the lost heterodyne correlations (whether classical or quantum), drastically augmenting the useful information accessible. The filtering even adjusts for moderate errors in the locking phase of the local oscillator. Hence we demonstrate the single-shot measurement of hundreds of different field quadratures allowing the rapid imaging of detailed features from a simple heterodyne trace. We also obtain a spectrum of hybrid homodyne-heterodyne character, with motional sidebands of combined amplitudes comparable to homodyne. Although investigated here in a thermal regime, the method's robustness and generality represents a promising new approach to sensing of quantum-scale displacements.

7.
Nutr Cancer ; 69(8): 1099-1104, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29043851

RESUMO

Several clinical trials have produced conflicting results regarding the benefit of antioxidants in cancer therapy thus questioning the incorporation of these substances in standard treatment regimens. Vitamins E and C, selenium, carotenoids, lycopene, soy products, and green tea extract are a few substances with antioxidant properties that have been studied in detail. This article reviews the results generated over the last 20 years through in vitro and in vivo studies in various types of cancers and stages of cancer treatment. Despite the commercial popularity and the multitude of studies examining antioxidant therapy, the true role of antioxidants is yet to be determined, requiring further investigation into its propagative, causal, or protective nature.


Assuntos
Antioxidantes/farmacologia , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Interações Medicamentosas , Humanos , Neoplasias/radioterapia , Radioterapia , Espécies Reativas de Oxigênio/metabolismo
8.
Eur Radiol ; 27(12): 5015-5023, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28677056

RESUMO

PURPOSE: To report the mid-term outcomes of percutaneous cryoablation (PCA) performed as second-line therapeutic option of venous malformations (VM). MATERIAL AND METHODS: From 2011 to 2015, PCA was offered in 24 patients (mean age: 31 years, range: 12-64) as second-line treatment for recurrence of symptoms after sclerotherapy and when resection was not possible (due to lesion location or previous failure) or refused by the patient. Adverse effects were recorded, disease-free survival (DFS) and local tissue control (LTC) rates were calculated based on symptoms and volume evolution. RESULTS: Mean follow-up was 18.7 months (6-48). Nine (37.5%, 9/24) adverse effects occurred and three (12.5%, 3/24) were severe. Mean pain assessed by visual analog scale (VAS) was 41.7 mm (0-80) before treatment and 20.3 mm (0-80) (p=0.01) after. Mean volume decreased significantly after treatment from 22.4 cm3 (0.9-146) to 8.35 cm3 (0-81.3) (p<0.001). Pain recurred in nine patients and size of one lesion increased. The DFS and LTC rates were 54% [95%CI: 22.94-77.27] and 93.33% [61.26-99.03] at 24 months, respectively. Only VM volume >10 cm3 was associated with a higher risk of local recurrence (p=0.05). CONCLUSION: PCA as second-line treatment appears to be safe and effective for local control of VM according to mid-term results. KEY POINTS: • Percutaneous cryoablation of venous malformations appeared well tolerated. • Size of venous malformations decreased significantly after percutaneous cryoablation (p<0.001). • Pain decreased significantly after percutaneous cryoablation of venous malformations (p=0.01).


Assuntos
Criocirurgia/métodos , Malformações Vasculares/cirurgia , Adolescente , Adulto , Criança , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/etiologia , Recidiva , Estudos Retrospectivos , Escleroterapia/métodos , Resultado do Tratamento , Malformações Vasculares/mortalidade , Adulto Jovem
9.
Osteoporos Int ; 27(8): 2395-410, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26902094

RESUMO

Teriparatide (TPTD) is the only currently available therapeutic agent that increases the formation of new bone tissue and can provide some remediation of the architectural defects in the osteoporotic skeleton. The use of teriparatide clinically is limited to 24 months. We review clinical findings during daily teriparatide treatment over time. Teriparatide appears to increase bone formation more than bone resorption as determined biochemically and histologically. Teriparatide exerts its positive effects on bone formation in two distinct fashions. The first is direct stimulation of bone formation that occurs within active remodeling sites (remodeling-based bone formation) and on surfaces of bone previously inactive (modeling-based bone formation). The second is an increase in the initiation of new remodeling sites. Both processes contribute to the final increase in bone density observed by non-invasive tools such as DXA. Remodeling is the repair process by which skeletal tissue is maintained in a young healthy state, and when stimulated by TPTD is associated with a positive bone balance within each remodeling cavity. It seems likely therefore that this component will contribute to the anti-fracture efficacy of TPTD. Teriparatide reduces the risk of fracture, and this effect appears to increase with longer duration of therapy. The use of novel treatment regimens, including shorter courses, should be held in abeyance until controlled clinical trials are completed to define the relative fracture benefits of such approaches in comparison to the 24-month daily use of the agent. Summary In patients with osteoporosis at high risk for fracture, the full continuous 24-month course with teriparatide results in improved skeletal health and outcomes than shorter time periods.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Osteoporose/tratamento farmacológico , Teriparatida/uso terapêutico , Densidade Óssea , Osso e Ossos/efeitos dos fármacos , Humanos
10.
Phys Rev Lett ; 116(10): 103601, 2016 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-27015479

RESUMO

We report the experimental observation of two-mode squeezing in the oscillation quadratures of a thermal micro-oscillator. This effect is obtained by parametric modulation of the optical spring in a cavity optomechanical system. In addition to stationary variance measurements, we describe the dynamic behavior in the regime of pulsed parametric excitation, showing an enhanced squeezing effect surpassing the stationary 3 dB limit. While the present experiment is in the classical regime, our technique can be exploited to produce entangled, macroscopic quantum optomechanical modes.

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