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1.
Arch. Soc. Esp. Oftalmol ; 98(2): 98-104, feb. 2023. tab, graf
Article in Spanish | IBECS | ID: ibc-215177

ABSTRACT

Objetivos Analizar la situación actual de la cirugía refractiva con implante de lente fáquica Visian ICL en España, señalando los rangos medios de potencias implantadas, los resultados visuales y refractivos obtenidos y los índices de seguridad y eficacia. Método Se trata de un estudio de población, transversal, descriptivo, analítico, retrospectivo, multicéntrico, en el que cada coautor recopiló los datos de, al menos, los 10 últimos pacientes (hasta un máximo de 30) con implante de lente fáquica Visian ICL. Se eligió aleatoriamente un ojo de cada sujeto para incluirlo en el estudio, y se analizaron las variables: edad, género, agudezas visuales sin corrección y con corrección pre y posquirúrgica, refracción preoperatoria y residual, queratometrías, recuento endotelial, profundidad de cámara anterior desde endotelio, paquimetría corneal central, presión intraocular, distancia blanco-blanco, lente implantada (potencia y talla) y equivalente esférico (SEQ) esperado y obtenido posquirúrgico al mes de la cirugía. Resultados Se obtuvo una muestra de 140 ojos de 140 pacientes con una edad media de 31,35±7,28 años. El SEQ preoperatorio medio fue de −6,33±3,69, la agudeza visual con corrección media de 0,96±0,16, la profundidad de cámara anterior desde endotelio de 3,30±0,29mm, distancia blanco-blanco 12,02±0,40mm, paquimetría corneal central 535,03±37,68μm, recuento endotelial 2.684,37±313,74céls/mm2 y presión intraocular 14,84±2,59mmHg. El 66,4% de las lentes implantadas fueron ICL esféricas y el 33,6% tóricas, con una potencia media de −7,81±4,09D y un cilindro medio de 2,27±1,23D. El 5,7% fueron hipermetrópicas. El 45,69% de las lentes implantadas eran de la talla 13,2mm, siendo el 37,93, 12,93 y 3,45% restante de las tallas 12,6, 12,1 y 13,7mm, respectivamente. Al mes de la cirugía se obtuvo un SEQ residual de −0,01±0,31D. Los índices de eficacia y seguridad fueron de 1,06±0,18 y 1,10±0,19, respectivamente... (AU)


Objectives To analyse the state of refractive surgery with Visian ICL phakic lens implantation in Spain, indicating the mean ranges of implanted powers, visual and refractive outcomes obtained and safety and efficacy indices. Method This is a population-based, cross-sectional, descriptive, analytical, retrospective, multicentre study in which each co-author collected data from at least the last 10 patients (up to a maximum of 30) with Visian ICL phakic lens implantation. One eye from each subject was randomly selected for study inclusion, and the variables analysed were: age, gender, visual acuities with and without correction pre and post-surgery, preoperative and residual refraction, keratometry, endothelial cellular density, anterior chamber depth from endothelium, central corneal pachymetry, intraocular pressure, white-white, implanted lens (power and size), expected and achieved spherical equivalent (SEQ) post-surgery at one month after surgery. Results A sample of 140 eyes was obtained from 140 patients with a mean age of 31.35±7.28 years. Mean preoperative SEQ was −6.33±3.69D, mean visual acuities with correction was 0.96±0.16, anterior chamber depth was 3.30±0.29mm, white-white 12.02±0.40mm, central corneal pachymetry 535.03±37.68μm, endothelial cellular density 2684.37±313.74cels/mm2 and intraocular pressure 14.84±2.59mmHg. A percentage of 66.4 of the implanted lenses were spherical ICLs and 33.6% toric, with a mean power of −7.81±4.09D and a mean cylinder of 2.27±1.23D. A percentage of 5.7 of the implanted lenses were hypermetropic. The mean SEQ target selected was +0.04±0.27D. A percentage of 45.69 of the implanted lenses were of size 13.2mm, with the remaining 37.93, 12.93 and 3.45% being of sizes 12.6, 12.1 and 13.7mm, respectively. At one month after surgery a residual SEQ of −0.01±0.31D was obtained. The efficacy and safety indices were 1.06±0.18 and 1.10±0.19...(AU)


Subject(s)
Humans , Male , Female , Young Adult , Adult , Middle Aged , Refractive Surgical Procedures , Phakic Intraocular Lenses , Myopia/surgery , Cross-Sectional Studies , Retrospective Studies , Safety , Efficacy
2.
Cereb Cortex ; 33(10): 6420-6434, 2023 05 09.
Article in English | MEDLINE | ID: mdl-36587289

ABSTRACT

The Compensation Related Utilization of Neural Circuits Hypothesis (CRUNCH) proposes a framework for understanding task-related brain activity changes as a function of healthy aging and task complexity. Specifically, it affords the following predictions: (i) all adult age groups display more brain activation with increases in task complexity, (ii) older adults show more brain activation compared with younger adults at low task complexity levels, and (iii) disproportionately increase brain activation with increased task complexity, but (iv) show smaller (or no) increases in brain activation at the highest complexity levels. To test these hypotheses, performance on a bimanual tracking task at 4 complexity levels and associated brain activation were assessed in 3 age groups (20-40, 40-60, and 60-80 years, n = 99). All age groups showed decreased tracking accuracy and increased brain activation with increased task complexity, with larger performance decrements and activation increases in the older age groups. Older adults exhibited increased brain activation at a lower complexity level, but not the predicted failure to further increase brain activity at the highest complexity level. We conclude that older adults show more brain activation than younger adults and preserve the capacity to deploy increased neural resources as a function of task demand.


Subject(s)
Brain , Longevity , Brain/physiology , Magnetic Resonance Imaging
3.
Arch Soc Esp Oftalmol (Engl Ed) ; 98(2): 98-104, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36115821

ABSTRACT

OBJECTIVES: To analyse the state of refractive surgery with Visian ICL phakic lens implantation in Spain, indicating the mean ranges of implanted powers, visual and refractive outcomes obtained and safety and efficacy indices. METHOD: This is a population-based, cross-sectional, descriptive, analytical, retrospective, multicentre study in which each co-author collected data from at least the last 10 patients (up to a maximum of 30) with Visian ICL phakic lens implantation. One eye from each subject was randomly selected for study inclusion, and the variables analysed were: age, gender, visual acuities with and without correction pre and post-surgery, preoperative and residualrefraction, keratometry, endothelial cellular density, anterior chamber depth from endothelium, central corneal pachymetry, intraocular pressure, white-white, implanted lens (power and size), expected and achieved spherical equivalent (SEQ) post-surgery at one month after surgery. RESULTS: A sample of 140 eyes was obtained from 140 patients with a mean age of 31.35 ± 7.28 years. Mean preoperative SEQ was -6.33 ± 3.69D, mean CDVA was 0.96 ± 0.16, ACD was 3.30 ± 0.29 mm, WTW 12.02 ± 0.40 mm, CCT 535.03 ± 37.68 µm, ECD 2684.37 ± 313.74 cels/mm2 and IOP 14.84 ± 2.59 mmHg. 66.4% of the implanted lenses were spherical ICLs and 33.6% toric, with a mean power of -7.81 ± 4.09D and a mean cylinder of 2.27 ± 1.23D. 5.7% of the implanted lenses were hypermetropic. The mean SEQ target selected was +0.04 ± 0.27D. 48.92% of the implanted lenses were of size 13.2 mm, with the remaining 36.69, 10.79 and 3.60% being of sizes 12.6, 12.1 and 13.7 mm, respectively. At one month after surgery a residual SEQ of -0.01 ± 0.31D was obtained. The efficacy and safety indices were 1.06 ± 0.18 and 1.10 ± 0.19, respectively. The mean central vault was 508.80 ± 201.04 µm. The accuracy between the calculated SEQ and the obtained SEQ was 99.3% for spherical lenses and 88.2% for Cyl correction. The mean ECD at 1 month after surgery was 2805.53±273.30céls/mm2, which was a difference from preoperative of 0.11% (p = 0.922), similarly, the mean IOP was 13.98 ± 2.57 mmHg, which was a difference of -0.92 ± 2.80 mmHg. CONCLUSIONS: ICL phakic lens surgery is an effective, safe and predictable procedure. There were no significant changes in endothelial cell count or intraocular pressure measurement one month after surgery.


Subject(s)
Myopia , Phakic Intraocular Lenses , Humans , Young Adult , Adult , Retrospective Studies , Spain , Cross-Sectional Studies , Myopia/surgery , Lens Implantation, Intraocular
4.
Neuroimage ; 252: 119025, 2022 05 15.
Article in English | MEDLINE | ID: mdl-35202812

ABSTRACT

Multiple functional changes occur in the brain with increasing age. Among those, older adults typically display more restricted fluctuations of brain activity, both during resting-state and task execution. These altered dynamic patterns have been linked to reduced task performance across multiple behavioral domains. Windowed functional connectivity, which is typically employed in the study of connectivity dynamics, however, might not be able to properly characterize moment-to-moment variations of individual networks. In the present study, we used innovation-driven co-activation patterns (ICAP) to overcome this limitation and investigate the length (duration) and frequency (innovation) in which various brain networks emerged across the adult lifespan (N= 92) during a resting-state period. We identified a link between increasing age and a tendency to engage brain areas with distinct functional associations simultaneously as a single network. The emergence of isolated and spatially well-defined visual, motor, frontoparietal, and posterior networks decreased with increased age. This reduction in dynamics of specialized networks mediated age-related performance decreases (i.e., increases in interlimb interference) in a bimanual motor task. Altogether, our findings demonstrated that older compared to younger adults tend to activate fewer network configurations, which include multiple functionally distinct brain areas. The reduction in independent emergence of functionally well-defined and task-relevant networks may reflect an expression of brain dedifferentiation and is likely associated with functional modulatory deficits, negatively impacting motor behavior.


Subject(s)
Aging , Magnetic Resonance Imaging , Aged , Aging/physiology , Brain/physiology , Brain Mapping , Humans , Longevity , Nerve Net/diagnostic imaging , Nerve Net/physiology , Neural Pathways/physiology , Task Performance and Analysis
5.
Sci Rep ; 11(1): 17154, 2021 Aug 25.
Article in English | MEDLINE | ID: mdl-34433863

ABSTRACT

The inherent scalability, low production cost and mechanical flexibility of laser-induced graphene (LIG) combined with its high electrical conductivity, hierarchical porosity and large surface area are appealing characteristics for many applications. Still, other materials can be combined with LIG to provide added functionalities and enhanced performance. This work exploits the most adequate electrodeposition parameters to produce LIG/ZnO nanocomposites. Low-temperature pulsed electrodeposition allowed the conformal and controlled deposition of ZnO rods deep inside the LIG pores whilst maintaining its inherent porosity, which constitute fundamental advances regarding other methods for LIG/ZnO composite production. Compared to bare LIG, the composites more than doubled electrode capacitance up to 1.41 mF cm-2 in 1 M KCl, while maintaining long-term cycle stability, low ohmic losses and swift electron transfer. The composites also display a luminescence band peaked at the orange/red spectral region, with the main excitation maxima at ~ 3.33 eV matching the expected for the ZnO bandgap at room temperature. A pronounced sub-bandgap tail of states with an onset absorption near 3.07 eV indicates a high amount of defect states, namely surface-related defects. This work shows that these environmentally sustainable multifunctional nanocomposites are valid alternatives for supercapacitors, electrochemical/optical biosensors and photocatalytic/photoelectrochemical devices.

6.
Arq. bras. med. vet. zootec. (Online) ; 73(2): 525-528, Mar.-Apr. 2021. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1248946

ABSTRACT

Existem poucos estudos sobre doenças infecciosas em animais silvestres. O objetivo deste estudo foi pesquisar DNA de Leptospira spp. em sangue de tartarugas mantidas em cativeiro, pertencentes ao Bosque Rodrigues Alves (Jardim Zoobotânico da Amazônia). O DNA foi isolado das amostras de sangue coletadas de 148 tartarugas pertencentes a seis espécies diferentes. A reação em cadeia da polimerase (PCR) foi realizada utilizando-se iniciadores específicos para DNA de Leptospira spp. Nenhuma das amostras apresentou resultado positivo para Leptospira spp.(AU)


Subject(s)
Animals , Turtles/microbiology , Leptospira/isolation & purification , Polymerase Chain Reaction/veterinary , Animals, Wild
9.
Phys Rev Lett ; 123(21): 210401, 2019 Nov 22.
Article in English | MEDLINE | ID: mdl-31809126

ABSTRACT

Dynamical decoupling (DD) is a powerful method for controlling arbitrary open quantum systems. In quantum spin control, DD generally involves a sequence of timed spin flips (π rotations) arranged to either average out or selectively enhance coupling to the environment. Experimentally, errors in the spin flips are inevitably introduced, motivating efforts to optimize error-robust DD. Here we invert this paradigm: by introducing particular control "errors" in standard DD, namely, a small constant deviation from perfect π rotations (pulse adjustments), we show we obtain protocols that retain the advantages of DD while introducing the capabilities of quantum state readout and polarization transfer. We exploit this nuclear quantum state selectivity on an ensemble of nitrogen-vacancy centers in diamond to efficiently polarize the ^{13}C quantum bath. The underlying physical mechanism is generic and paves the way to systematic engineering of pulse-adjusted protocols with nuclear state selectivity for quantum control applications.

10.
Neuroimage ; 194: 93-104, 2019 07 01.
Article in English | MEDLINE | ID: mdl-30872046

ABSTRACT

Brain networks undergo widespread changes in older age. A large body of knowledge gathered about those changes evidenced an increase of functional connectivity between brain networks. Previous work focused mainly on cortical networks during the resting state. Subcortical structures, however, are of critical importance during the performance of motor tasks. In this study, we investigated age-related changes in cortical, striatal and cerebellar functional connectivity at rest and its modulation by motor task execution. To that end, functional MRI from twenty-five young (mean age 21.5 years) and eighteen older adults (mean age 68.6 years) were analysed during rest and while performing a bimanual tracking task practiced over a two-week period. We found that inter-network connectivity among cortical structures was more positive in older adults both during rest and task performance. Functional connectivity within striatal structures decreased with age during rest and task execution. Network flexibility, the changes in network composition from rest to task, was also reduced in older adults, but only in networks with an age-related increase in connectivity. Finally, flexibility of areas in the prefrontal cortex were associated with lower error scores during task execution, especially in older adults. In conclusion, our findings indicate an age-related reduction in the ability to suppress irrelevant network communication, leading to less segregated and less flexible cortical networks. At the same time, striatal connectivity is impaired in older adults, while cerebellar connectivity shows heterogeneous age-related effects during rest and task execution. Future research is needed to clarify how cortical and subcortical connectivity changes relate to one another.


Subject(s)
Aging/physiology , Brain/physiology , Motor Activity/physiology , Neural Pathways/physiology , Aged , Female , Humans , Learning/physiology , Male , Rest , Young Adult
12.
Phys Rev Lett ; 120(2): 020503, 2018 Jan 12.
Article in English | MEDLINE | ID: mdl-29376724

ABSTRACT

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.

13.
J Appl Microbiol ; 124(1): 85-96, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29095556

ABSTRACT

AIMS: This work aimed to evaluate the antibacterial and antifungal activities of two types of pyroligneous acid (PA) obtained from slow pyrolysis of wood of Mimosa tenuiflora and of a hybrid of Eucalyptus urophylla × Eucalyptus grandis. METHODS AND RESULTS: Wood wedges were carbonized on a heating rate of 1·25°C min-1 until 450°C. Pyrolysis smoke was trapped and condensed to yield liquid products. Crude pyrolysis liquids were bidistilled under 5 mmHg vacuum yielding purified PA. Multi-antibiotic-resistant strains of Escherichia coli, Pseudomonas aeruginosa (ATCC 27853) and Staphylococcus aureus (ATCC 25923) had their sensitivity to PA evaluated using agar diffusion test. Two yeasts were evaluated as well, Candida albicans (ATCC 10231) and Cryptococcus neoformans. GC-MS analysis of both PAs was carried out to obtain their chemical composition. Regression analysis was performed, and models were adjusted, with diameter of inhibition halos and PA concentration (100, 50 and 20%) as parameters. Identity of regression models and equality of parameters in polynomial orthogonal equations were verified. Inhibition halos were observed in the range 15-25 mm of diameter. CONCLUSIONS: All micro-organisms were inhibited by both types of PA even in the lowest concentration of 20%. SIGNIFICANCE AND IMPACT OF THE STUDY: The feasibility of the usage of PAs produced with wood species planted in large scale in Brazil was evident and the real potential as a basis to produce natural antibacterial and antifungal agents, with real possibility to be used in veterinary and zootechnical applications.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antifungal Agents/pharmacology , Eucalyptus/chemistry , Mimosa/chemistry , Terpenes/pharmacology , Anti-Bacterial Agents/isolation & purification , Antifungal Agents/isolation & purification , Brazil , Escherichia coli/drug effects , Microbial Sensitivity Tests , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Terpenes/isolation & purification , Wood/chemistry , Yeasts/drug effects
14.
Cereb Cortex ; 28(12): 4390-4402, 2018 12 01.
Article in English | MEDLINE | ID: mdl-29136114

ABSTRACT

Aging is typically associated with substantial declines in motor functioning as well as robust changes in the functional organization of brain networks. Previous research has investigated the link between these 2 age-varying factors but examinations were predominantly limited to the functional organization within motor-related brain networks. Little is known about the relationship between age-related behavioral impairments and changes in functional organization at the whole brain (i.e., multiple network) level. This knowledge gap is surprising given that the decreased segregation of brain networks (i.e., increased internetwork connectivity) can be considered a hallmark of the aging process. Accordingly, we investigated the association between declines in motor performance across the adult lifespan (20-75 years) and age-related modulations of functional connectivity within and between resting state networks. Results indicated that stronger internetwork resting state connectivity observed as a function of age was significantly related to worse motor performance. Moreover, performance had a significantly stronger association with the strength of internetwork as compared with intranetwork connectivity, including connectivity within motor networks. These findings suggest that age-related declines in motor performance may be attributed to a breakdown in the functional organization of large-scale brain networks rather than simply age-related connectivity changes within motor-related networks.


Subject(s)
Aging/physiology , Aging/psychology , Brain/physiology , Psychomotor Performance/physiology , Adult , Aged , Brain Mapping , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neural Pathways/physiology , Young Adult
17.
ACS Appl Mater Interfaces ; 9(4): 4084-4099, 2017 Feb 01.
Article in English | MEDLINE | ID: mdl-28111948

ABSTRACT

In this work, the exceptionally improved sensing capability of highly porous three-dimensional (3-D) hybrid ceramic networks toward reducing gases is demonstrated for the first time. The 3-D hybrid ceramic networks are based on doped metal oxides (MexOy and ZnxMe1-xOy, Me = Fe, Cu, Al) and alloyed zinc oxide tetrapods (ZnO-T) forming numerous junctions and heterojunctions. A change in morphology of the samples and formation of different complex microstructures is achieved by mixing the metallic (Fe, Cu, Al) microparticles with ZnO-T grown by the flame transport synthesis (FTS) in different weight ratios (ZnO-T:Me, e.g., 20:1) followed by subsequent thermal annealing in air. The gas sensing studies reveal the possibility to control and change/tune the selectivity of the materials, depending on the elemental content ratio and the type of added metal oxide in the 3-D ZnO-T hybrid networks. While pristine ZnO-T networks showed a good response to H2 gas, a change/tune in selectivity to ethanol vapor with a decrease in optimal operating temperature was observed in the networks hybridized with Fe-oxide and Cu-oxide. In the case of hybridization with ZnAl2O4, an improvement of H2 gas response (to ∼7.5) was reached at lower doping concentrations (20:1), whereas the increase in concentration of ZnAl2O4 (ZnO-T:Al, 10:1), the selectivity changes to methane CH4 gas (response is about 28). Selectivity tuning to different gases is attributed to the catalytic properties of the metal oxides after hybridization, while the gas sensitivity improvement is mainly associated with additional modulation of the electrical resistance by the built-in potential barriers between n-n and n-p heterojunctions, during adsorption and desorption of gaseous species. Density functional theory based calculations provided the mechanistic insights into the interactions between different hybrid networks and gas molecules to support the experimentally observed results. The studied networked materials and sensor structures performances would provide particular advantages in the field of fundamental research, applied physics studies, and industrial and ecological applications.

18.
Spectrochim Acta A Mol Biomol Spectrosc ; 172: 163-167, 2017 Feb 05.
Article in English | MEDLINE | ID: mdl-27133357

ABSTRACT

Rare earth orthosilicates are among the most widely used scintillator materials in the last decades. Particularly, lutetium-yttrium oxyorthosilicate (LYSO) is known to exhibit great potentialities in the field of radiation detectors for medical imaging. Consequently, an in-depth knowledge of the material properties is of utmost interest for the mentioned applications. In this work the spectroscopic properties of commercial cerium doped lutetium-yttrium oxyorthosilicate crystals (LYSO:Ce) were investigated by Raman spectroscopy, steady state photoluminescence, photoluminescence excitation and time resolved photoluminescence. Site selective excitation was used under steady state (325nm) and pulsed (266nm) conditions to separately investigate the temperature dependence of the 5d→4f Ce1 and Ce2 luminescence, allowing to establish the thermal quenching dependence of the Ce2 optical center. In the case of the Ce1 optical center, a luminescence quantum efficiency of 78% was obtained from 14K to room temperature with 266nm photon excitation.

19.
Sci Total Environ ; 579: 337-344, 2017 Feb 01.
Article in English | MEDLINE | ID: mdl-27887838

ABSTRACT

Nanotechnology is a rising field and nanomaterials can now be found in a vast variety of products with different chemical compositions, sizes and shapes. New nanostructures combining different nanomaterials are being developed due to their enhancing characteristics when compared to nanomaterials alone. In the present study, the toxicity of a nanostructure composed by a ZnO nanomaterial with Ag nanomaterials on its surface (designated as ZnO/Ag nanostructure) was assessed using the model-organism Daphnia magna and its toxicity predicted based on the toxicity of the single components (Zn and Ag). For that ZnO and Ag nanomaterials as single components, along with its mixture prepared in the laboratory, were compared in terms of toxicity to ZnO/Ag nanostructures. Toxicity was assessed by immobilization and reproduction tests. A mixture toxicity approach was carried out using as starting point the conceptual model of Concentration Addition. The laboratory mixture of both nanomaterials showed that toxicity was dependent on the doses of ZnO and Ag used (immobilization) or presented a synergistic pattern (reproduction). The ZnO/Ag nanostructure toxicity prediction, based on the percentage of individual components, showed an increase in toxicity when compared to the expected (immobilization) and dependent on the concentration used (reproduction). This study demonstrates that the toxicity of the prepared mixture of ZnO and Ag and of the ZnO/Ag nanostructure cannot be predicted based on the toxicity of their components, highlighting the importance of taking into account the interaction between nanomaterials when assessing hazard and risk.


Subject(s)
Nanostructures/toxicity , Silver/toxicity , Toxicity Tests, Acute , Water Pollutants, Chemical/toxicity , Zinc Oxide/toxicity , Animals , Daphnia
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