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1.
Psychophysiology ; 60(12): e14439, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37750509

RESUMO

For motor learning, the processing of behavioral outcomes is of high significance. The feedback-related negativity (FRN) is an event-related potential, which is often described as a correlate of the reward prediction error in reinforcement learning. The number of studies examining the FRN in motor tasks is increasing. This meta-analysis summarizes the component in the motor domain and compares it to the cognitive domain. Therefore, a data set of a previous meta-analysis in the cognitive domain that comprised 47 studies  was reanalyzed and compared to additional 25 studies of the motor domain. Further, a moderator analysis for the studies in the motor domain was conducted. The FRN amplitude was higher in the motor domain than in the cognitive domain. This might be related to a higher task complexity and a higher feedback ambiguity of motor tasks. The FRN latency was shorter in the motor domain than in the cognitive domain. Given that sensory information can be used as an external feedback predictor prior to the presentation of the final feedback, reward processing in the motor domain may have been faster and reduced the FRN latency. The moderator variable analysis revealed that the feedback modality influenced the FRN latency, with shorter FRN latencies after bimodal than after visual feedback. Processing of outcome feedback seems to share basic principles in both domains; however, differences exist and should be considered in FRN studies. Future research is motivated to scrutinize the effects of bimodal feedback and other moderators within the motor domain.


Assuntos
Eletroencefalografia , Retroalimentação Psicológica , Humanos , Retroalimentação , Potenciais Evocados , Recompensa , Cognição
2.
Mar Pollut Bull ; 193: 115009, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37327721

RESUMO

The main objective of subsea mechanical dispersion (SSMD) is to reduce the oil droplet sizes from a subsea oil release, thereby influencing the fate and behaviour of the released oil in the marine environment. Subsea water jetting was identified as a promising method for SSMD and imply that a water jet is used to reduce the particle size of the oil droplets initially formed from the subsea release. This paper presents the main findings from a study including small-scale testing in a pressurised tank, via laboratory basin testing, to large-scale outdoor basin testing. The effectiveness of SSMD increases with the scale of the experiments. From a five-fold reduction in droplet sizes for small-scale experiments to more than ten-fold for large-scale experiments. The technology is ready for full-scale prototyping and field testing. Large-scale experiments performed at Ohmsett indicate that SSMD could be comparable to subsea dispersant injection (SSDI) in reducing oil droplet sizes.


Assuntos
Poluição por Petróleo , Petróleo , Poluentes Químicos da Água , Poluição por Petróleo/análise , Água , Poluentes Químicos da Água/análise , Tamanho da Partícula
3.
Polymers (Basel) ; 15(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37177276

RESUMO

Poly(ethylene oxide) block copolymers (PEOz BCP) have been demonstrated to exhibit remarkably high lithium ion (Li+) conductivity for Li+ batteries applications. For linear poly(isoprene)-b-poly(styrene)-b-poly(ethylene oxide) triblock copolymers (PIxPSyPEOz), a pronounced maximum ion conductivity was reported for short PEOz molecular weights around 2 kg mol-1. To later enable a systematic exploration of the influence of the PIx and PSy block lengths and related morphologies on the ion conductivity, a synthetic method is needed where the short PEOz block length can be kept constant, while the PIx and PSy block lengths could be systematically and independently varied. Here, we introduce a glycidyl ether route that allows covalent attachment of pre-synthesized glycidyl-end functionalized PEOz chains to terminate PIxPSy BCPs. The attachment proceeds to full conversion in a simplified and reproducible one-pot polymerization such that PIxPSyPEOz with narrow chain length distribution and a fixed PEOz block length of z = 1.9 kg mol-1 and a D = 1.03 are obtained. The successful quantitative end group modification of the PEOz block was verified by nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). We demonstrate further that with a controlled casting process, ordered microphases with macroscopic long-range directional order can be fabricated, as demonstrated by small-angle X-ray scattering (SAXS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It has already been shown in a patent, published by us, that BCPs from the synthesis method presented here exhibit comparable or even higher ionic conductivities than those previously published. Therefore, this PEOz BCP system is ideally suitable to relate BCP morphology, order and orientation to macroscopic Li+ conductivity in Li+ batteries.

4.
Eur J Neurosci ; 57(8): 1297-1316, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36878863

RESUMO

Supplementing an earlier analysis of event-related potentials in extensive motor learning (Margraf et al., 2022a, 2022b), frontal theta-band activity (4-8 Hz) was scrutinized. Thirty-seven participants learned a sequential arm movement with 192 trials in each of five practice sessions. Feedback, based on a performance adaptive bandwidth, was given after every trial. Electroencephalogram (EEG) was recorded in the first and last practice sessions. The degree of motor automatization was tested under dual-task conditions in a pre-test-post-test design. Quantitative error information was transported in both feedback conditions (positive and negative). Frontal theta activity was discussed as a general signal that cognitive control is needed and, therefore, was expected to be higher after negative feedback. Extensive motor practice promotes automatization, and therefore, decreased frontal theta activity was expected in the later practice. Further, it was expected that frontal theta was predictive for subsequent behavioural adaptations and the amount of motor automatization. As the results show, induced frontal theta power was higher after negative feedback and decreased after five sessions of practice. Moreover, induced theta activity was predictive for error correction and, therefore, an indicator of whether the recruited cognitive resources successfully induced behavioural adaptations. It remains to be solved why these effects, which fit well with the theoretical assumptions, were only revealed by the induced part of frontal theta activity. Further, the amount of theta activity during practice was not predictive for the degree of motor automatization. It seems that there might be a dissociation between attentional resources associated with feedback processing and attentional resources associated with motor control.


Assuntos
Eletroencefalografia , Aprendizagem , Humanos , Retroalimentação , Potenciais Evocados , Atenção , Ritmo Teta
5.
Psychol Res ; 87(7): 2259-2274, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36871080

RESUMO

Action imagery practice (AIP) describes the repetitive imagination of an action to improve subsequent action execution. Because AIP and action execution practice (AEP) draw on partly similar motor mechanisms, it was assumed that AIP may lead to motor automatization, which is observable in a reduction of dual-task costs after AEP. To investigate automatization in AIP, we compared dual-task and single-task performance in practice and random sequences in pretests and posttests. All participants practiced serial reactions to visual stimuli in ten single-task practice sessions. An AIP group imagined the reactions. An AEP group and a control practice group executed the reactions. Practice followed a sequential sequence in AIP and AEP but was random in control practice. In dual-task test conditions, tones were counted that appeared in addition to the visual stimuli. RTs decreased from pretest to posttest in both practice and random sequences in all groups indicating general sequence-unspecific learning. Further, RTs decreased to a greater extent in the practice sequence than in the random sequence after AIP and AEP, indicating sequence-specific learning. Dual-task costs-the difference between RTs after tone and no tone events-were reduced independent from the performed sequence in all groups indicating sequence-unspecific automatization. It is concluded that the stimulus-response coupling can be automatized by both, AEP and AIP.


Assuntos
Aprendizagem , Destreza Motora , Humanos , Destreza Motora/fisiologia , Aprendizagem/fisiologia , Imaginação/fisiologia , Análise e Desempenho de Tarefas , Eletromiografia
6.
Res Q Exerc Sport ; 94(2): 568-577, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35426763

RESUMO

Purpose: In basketball, tactical instructions are presented on tactic boards under temporal constraints (e.g., time-outs). Based on the disparity in the orientation of the tactic board and the players' egocentric on-court visual perspective, there are high affordances in visual-spatial transformation (e.g., mental rotation), which impede information processing and decrease execution accuracy. The aim of this study was to scrutinize how the effect of different orientations of visual tactical displays on information processing demands and execution accuracy is affected by expertise in basketball. Methods: In a mixed-factors-design with two factors, 48 participants were assigned to a group of experienced basketball players (n = 24) and novices (n = 24). They were instructed to execute basketball playing patterns, which were presented on a virtual tactic board in five different spatial disparities to the players' on-court perspective. Results: The self-controlled time for watching the instructions before execution was significantly shorter and spatial accuracy in pattern execution was significantly higher for lower disparities between instruction perspective and on-court perspective. Experienced basketball players displayed shorter observation times as well as higher accuracy as a global effect, being independent of stimulus orientation. Moreover, the effect of orientation on observation times was lower in the experienced group as compared to the novices. Conclusion: Extensive experience over several years with visuo-spatial transformations of tactical instructions reduced, but not eliminated, the effects of model-observer disparity. Accordingly, coaches should align their tactic boards to their players' on-court viewing perspective to enable fast processing and errorless execution of tactical instructions.


Assuntos
Desempenho Atlético , Basquetebol , Humanos , Cognição
7.
Neuroscience ; 486: 20-36, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33945795

RESUMO

To examine the neural processing of valence-dependent augmented feedback, 38 students learned a sequential arm movement task with 192 trials in each of five practice sessions. The degree of motor automatization was tested under dual-task-conditions. Electroencephalogram (EEG) was recorded in the first and last practice session. This study is an additional analysis of the data from Margraf et al. [Margraf, L., Krause, D., & Weigelt, M. (this issue). Valence-dependent neural correlates of augmented feedback processing in extensive motor sequence learning - Part I: Practice-related changes of feedback processing.]. While Part I focused on changes in neural feedback processing after extensive motor practice, Part II examines coherences between neural feedback processing and short-term behavioral adaptations, as well as different dimensions of long-term learning (i.e., accuracy, consistency, and automaticity). It was found that more negative amplitudes of the feedback-related-negativity (FRN) after negative feedback were predictive for goal-independent changes of behavior in the early practice phase, whereas more positive amplitudes of the late fronto-central positivity (LFCP) after negative feedback were predictive for goal-directed behavioral adaptations (error reduction), independent from the practice phase. Unexpectedly, more positive amplitudes of the P300 after positive feedback were also predictive for goal-directed behavioral adaptations. Concerning long-term learning and motor automatization, a positive correlation was found for the reduction of dual-task costs (DTC) and LFCP-amplitudes after positive feedback in the early practice.


Assuntos
Potenciais Evocados , Retroalimentação Psicológica , Adaptação Fisiológica , Eletroencefalografia/métodos , Retroalimentação , Humanos , Aprendizagem
8.
Neuroscience ; 486: 4-19, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33945843

RESUMO

Several event-related potentials (ERPs) are associated with the processing of valence-dependent augmented feedback during the practice of motor tasks. In this study, 38 students learned a sequential arm-movement-task with 192 trials in each of five practice sessions (960 practice trials in total), to examine practice-related changes in neural feedback processing. Electroencephalogram (EEG) was recorded in the first and last practice session. An adaptive bandwidth for movement accuracy led to equal amounts of positive and negative feedback. A frontal located negative deflection in the time window of the feedback-related negativity (FRN) was more negative for negative feedback and might reflect reward prediction errors in reinforcement learning. This negativity increased after extensive practice, which might indicate that smaller errors are harder to identify in the later phase. The late fronto-central positivity (LFCP) was more positive for negative feedback and is assumed to be associated with supervised learning and behavioral adaptations based on feedback with higher complexity. No practice-related changes of the LFCP were observed, which suggests that complex feedback is processed independent from the practice phase. The P300 displayed a more positive activation for positive feedback, which might be interpreted as the higher significance of positive feedback for the updating of internal models in this setting. A valence-independent increase of the P300 amplitude after practice might reflect an improved ability to update the internal representation based on feedback information. These results demonstrate that valence-dependent neural feedback processing changes with extensive practice of a novel motor task. Dissociating changes in latencies of different components support the assumption that they are related to distinct mechanisms of feedback-dependent learning.


Assuntos
Potenciais Evocados , Retroalimentação Psicológica , Eletroencefalografia , Potenciais Evocados/fisiologia , Retroalimentação , Retroalimentação Psicológica/fisiologia , Humanos , Recompensa
9.
Klin Monbl Augenheilkd ; 238(11): 1213-1219, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34528231

RESUMO

PURPOSE: To evaluate the reliability of spectral-domain optical coherence tomography (SD-OCT; RTVue XR; Optovue, Inc., Fremont, CA, USA) for thickness mapping of the entire cornea (CT), corneal epithelium (ET). and corneal stroma (ST) over a 9-mm zone in healthy eyes. We sought to develop reference values for different age groups and elucidate potential sex- and age-dependent characteristics of corneal sublayer pachymetry maps. METHODS: Three consecutive SD-OCT scans were obtained in 166 healthy right eyes (mean age = 50 ± 20 years). The thickness maps contain 25 sectors over a 9-mm diameter zone. To test measurement reliability, intraclass correlation coefficients (ICC), coefficients of variation (CoV), and within-subject standard deviations (WSSD) were calculated. RESULTS: CT, ET, and ST ICCs ranged from 0.961 to 0.998, 0.896 to 0.945, and 0.955 to 0.998, respectively. CoV values for CT, ET, and ST ranged between 0.3 and 1.5%, 1.6 and 4.2%, and 0.4 and 1.7%, respectively. WSSD ranged from 6 to 41, 4 to 8, and 7 to 46 µm, respectively. A negative correlation was found between age and ET (p < 0.05) but not between age and ST or CT. No gender-related differences in CT, ET, or ST were detected. CoV of CT, ET, and ST measurements showed a positive correlation with age in 28, 64, and 28% of the sectors, respectively. CONCLUSION: SD-OCT is a rapid and noninvasive technique that provides excellent reliability for corneal sublayer thickness measurements over a 9-mm zone. The reliability of the ET measurement seems to be negatively affected by age. Peripheral CT and global ET thin with age.


Assuntos
Epitélio Corneano , Tomografia de Coerência Óptica , Adulto , Idoso , Córnea , Paquimetria Corneana , Epitélio Corneano/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
10.
Eur J Neurosci ; 54(4): 5384-5403, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34241932

RESUMO

The present study examines if the neural signature of information processing in mental rotation tasks is moderated by stimulus characteristics (e.g., body-related vs. non-body-related stimuli). In the present experiment, stimulus sets of human figures (back view; left vs. right arm abduction) and alphanumeric characters ('R'; normal vs. mirrored view) were scrutinized with event-related potentials (ERPs) in the electroencephalography (EEG). Participants had to judge parity between an upright (0° orientation) and a comparison stimulus (stimulus disparity; 0°, 45°, 90°, 135° or 180°). There was a main effect of stimulus disparity for the behavioural (response time and error rates), as well as for the neural data (rotation-related negativity, RRN). The interaction of stimulus disparity and stimulus type was significant for the RRN, but not for the response time. Lower RRN amplitudes for letters indicate a more pronounced use of alternative processes (e.g., memory retrieval), which seems to be reflected in higher N350 amplitudes. Moreover, the increase of the RRN amplitude and the increase in response time as a function of disparity were positively correlated. Task differences were evident for several ERP components (i.e., N150, P150 and N250), being independent of disparity, which might reflect differences in early and late object cognition prior to the mental rotation process itself. This might be associated with the task-dependent activation of embodied cognition processes in mental rotation tasks.


Assuntos
Potenciais Evocados , Corpo Humano , Cognição , Eletroencefalografia , Humanos , Tempo de Reação
11.
Sci Total Environ ; 794: 148593, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34323752

RESUMO

Understanding of biological responses of marine fauna to seawater acidification due to potential CO2 leakage from sub-seabed storage sites has improved recently, providing support to CCS environmental risk assessment. Physiological responses of benthic organisms to ambient hypercapnia have been previously investigated but rarely at the cellular level, particularly in areas of less common geochemical and ecological conditions such as brackish water and/or reduced oxygen levels. In this study, CO2-related responses of oxygen-dependent, antioxidant and detoxification systems as well as markers of neurotoxicity and acid-base balance in the Baltic clam Limecola balthica from the Baltic Sea were quantified in 50-day experiments. Experimental conditions included CO2 addition producing pH levels of 7.7, 7.0 and 6.3, respectively and hydrostatic pressure 900 kPa, simulating realistic seawater acidities following a CO2 seepage accident at the potential CO2-storage site in the Baltic. Reduced pH interfered with most biomarkers studied, and modifications to lactate dehydrogenase and malate dehydrogenase indicate that aerobiosis was a dominant energy production pathway. Hypercapnic stress was most evident in bivalves exposed to moderately acidic seawater environment (pH 7.0), showing a decrease of glutathione peroxidase activity, activation of catalase and suppression of glutathione S-transferase activity likely in response to enhanced free radical production. The clams subjected to pH 7.0 also demonstrated acetylcholinesterase activation that might be linked to prolonged impact of contaminants released from sediment. The most acidified conditions (pH 6.3) stimulated glutathione and malondialdehyde concentration in the bivalve tissue suggesting potential cell damage. Temporal variations of most biomarkers imply that after a 10-to-15-day initial phase of an acute disturbance, the metabolic and antioxidant defence systems recovered their capacities.


Assuntos
Bivalves , Poluentes Químicos da Água , Animais , Dióxido de Carbono/análise , Dióxido de Carbono/toxicidade , Concentração de Íons de Hidrogênio , Pressão Hidrostática , Água do Mar , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
12.
PLoS Genet ; 17(6): e1009619, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34161347

RESUMO

Lysosome-associated membrane glycoprotein 3 (LAMP3) is a type I transmembrane protein of the LAMP protein family with a cell-type-specific expression in alveolar type II cells in mice and hitherto unknown function. In type II pneumocytes, LAMP3 is localized in lamellar bodies, secretory organelles releasing pulmonary surfactant into the extracellular space to lower surface tension at the air/liquid interface. The physiological function of LAMP3, however, remains enigmatic. We generated Lamp3 knockout mice by CRISPR/Cas9. LAMP3 deficient mice are viable with an average life span and display regular lung function under basal conditions. The levels of a major hydrophobic protein component of pulmonary surfactant, SP-C, are strongly increased in the lung of Lamp3 knockout mice, and the lipid composition of the bronchoalveolar lavage shows mild but significant changes, resulting in alterations in surfactant functionality. In ovalbumin-induced experimental allergic asthma, the changes in lipid composition are aggravated, and LAMP3-deficient mice exert an increased airway resistance. Our data suggest a critical role of LAMP3 in the regulation of pulmonary surfactant homeostasis and normal lung function.


Assuntos
Células Epiteliais Alveolares/metabolismo , Asma/genética , Homeostase/genética , Proteína 3 de Membrana Associada ao Lisossomo/genética , Proteína C Associada a Surfactante Pulmonar/genética , Surfactantes Pulmonares/metabolismo , Resistência das Vias Respiratórias , Células Epiteliais Alveolares/patologia , Animais , Asma/induzido quimicamente , Asma/metabolismo , Asma/patologia , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Feminino , Edição de Genes/métodos , Regulação da Expressão Gênica , Lipidômica , Pulmão/metabolismo , Pulmão/patologia , Proteína 3 de Membrana Associada ao Lisossomo/deficiência , Camundongos , Camundongos Knockout , Ovalbumina/administração & dosagem , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Proteína C Associada a Surfactante Pulmonar/metabolismo , Testes de Função Respiratória , Transdução de Sinais
13.
Br J Ophthalmol ; 105(12): 1638-1644, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33055086

RESUMO

PURPOSE: To evaluate the capability of wide-field spectral-domain optical coherence tomography (SD-OCT) corneal sublayer pachymetry to distinguish between keratoconus and pellucid marginal degeneration (PMD). METHODS: This prospective cross-sectional study included 69 eyes (59 with keratoconus and 10 with PMD) of 69 patients. All patients were examined three subsequent times with the RTVue XR system. Pachymetry maps of the total cornea (CT), the epithelium (ET) and the stroma were generated using the onboard software. For analysis of reliability, the coefficients of variation and intraclass correlation coefficients (ICC) were calculated. Receiver operating characteristic analyses were performed to elaborate the most accurate pachymetric parameters for distinguishing between PMD and keratoconus. RESULTS: Overall repeatability of (sublayer) pachymetry was comparably good in both keratoconus (ICC ranging between 0.827 and 0.986) and PMD (ICC ranging between 0.753 and 0.998). Measurement reliability in keratoconic eyes was a negative function of Kmax (p<0.05). As compared with keratoconus, PMD exhibited higher CT (526±31 µm vs 503±30 µm; p=0.02) and ET (56±7 µm vs 51±5 µm; p=0.02) in the inferotemporal 2-5 mm sector as well as lower ET in the inferior 7-9 mm sector (52±5 µm vs 57±5 µm; p<0.01). The calculated ratio between CT in the inferotemporal 2-5 mm and in the inferior 7-9 mm sector yielded the highest diagnostic accuracy for distinguishing between PMD and keratoconus with an area under the curve of 0.977 and an optimal cut-off value of 0.90. CONCLUSION: Wide-field SD-OCT corneal sublayer pachymetry showed good reliability in PMD and keratoconus and may be useful to differentiate between the two ectatic diseases.


Assuntos
Ceratocone , Córnea , Paquimetria Corneana , Topografia da Córnea , Estudos Transversais , Humanos , Ceratocone/diagnóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Tomografia de Coerência Óptica/métodos
14.
Chemosphere ; 264(Pt 2): 128552, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33065323

RESUMO

Carbon capture and storage (CCS) is one of the most promising mitigation strategies for reducing the emissions of carbon dioxide (CO2) to the atmosphere and may substantially help to decelerate global warming. There is an increasing demand for CCS sites. Nevertheless, there is a lack of knowledge of the environmental risk associated with potential leakage of CO2 from the storage sites; and even more, what happens when the seepage stops. Can the environment return to the initial equilibrium? Potential effects on native macrofauna were studied under a scenario of a 50-day CO2 leakage, and the subsequent leak closure. To accomplish the objective, Trondheim Fjord sediments and clams were exposed to an acidified environment (pH 6.9) at 29 atm for 7 weeks followed by a 14-day recovery at normal seawater conditions (pH 8.0, 29 atm). Growth and survival of clams exposed to pressure (29 atm) and reduced pH (6.9) did not significantly differ from control clams kept at 1 atm in natural seawater. Furthermore, bioaccumulation of elements in the soft tissue of clams did not register significant variations for most of the analysed elements (Cd, Cr, Pb, and Ti), while other elements (As, Cu, Fe, Ni) had decreasing concentrations in tissues under acidified conditions in contrast to Na and Mg, which registered an uptake (Ku) of 111 and 9.92 µg g-1dw d-1, respectively. This Ku may be altered due to the stress induced by acidification; and the element concentration being released from sediments was not highly affected at that pH. Therefore, a 1 unit drop in pH at the seafloor for several weeks does not appear to pose a risk for the clams.


Assuntos
Bivalves , Poluentes Químicos da Água , Animais , Dióxido de Carbono/análise , Mudança Climática , Sedimentos Geológicos , Concentração de Íons de Hidrogênio , Água do Mar , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
15.
Sci Total Environ ; 755(Pt 2): 143170, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33158534

RESUMO

A high proportion of the total microplastic (MP) load in the marine environment has been identified as microfibers (MFs), with polyester (PET) and polyamide (PA) typically found in the highest abundance. The potential for negative environmental impacts from MPs may be dependent on their degree of degradation in the environment, which is influenced by both intrinsic properties (polymer type, density, size, additive chemicals) and extrinsic environmental parameters. Most polymer products break down slowly through a combination of environmental processes, but UV degradation can be a significant source of degradation. The current study aimed to investigate the effect of UV irradiance on the degradation of natural (wool) and synthetic (PET and PA) MFs. Degradation of MFs was conducted in seawater under environmentally relevant accelerated exposure conditions using simulated sunlight. After 56 days of UV exposure, PA primarily exhibited changes in surface morphology with no significant fragmentation observed. PET and wool fibers exhibited both changes in surface morphology and fragmentation into smaller particles. A range of molecular degradation products were identified in seawater leachates after UV exposure, with increasing abundance over the duration of the experiment. Furthermore, a variety of additive chemicals were shown to leach from the MFs into seawater. While some of these chemicals were also susceptible to UV degradation and some are expected to biodegrade rapidly, others may be persistent and contribute to the overall load of chemical pollution in the marine environment.

16.
Sci Rep ; 10(1): 19308, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-33168836

RESUMO

Keratoconus is a progressive ectatic corneal disorder, which can result in severe visual impairment. The new ABCD keratoconus classification system allows differentiated description of the disease. Aim of the study was to evaluate the components of this novel staging system (ARC, PRC, thinnest pachymetry) as well as topometric indices, deviation of normality indices, and other parameters in terms of repeatability and reliability. 317 eyes with keratoconus were examined twice with a Scheimpflug device (Pentacam, Oculus). Bland Altman analysis and intraclass correlations were carried out to evaluate the parameters repeatability and reliability. Apart from IHA (ICC = 0.730), all parameters showed excellent reliability (ICC > 0.900). ARC, PRC, thinnest pachymetry, Kmax, CKI, KI, Rmin, and Progression Avg were the best repeatable parameters with relative repeatability values < 2.5%. Other parameters performing well in terms of repeatability were IHD, ISV, IVA, and final D (RR < 13%). Regression analysis revealed consistently high repeatability along all stages of keratoconus for PRC, thinnest pachymetry, and CKI. All parameters of the ABCD staging system showed excellent reliability and repeatability, PRC and thinnest pachymetry even at all stages of keratoconus and can consequently be reliably used in the determination of keratoconus progression.


Assuntos
Córnea/diagnóstico por imagem , Paquimetria Corneana/instrumentação , Topografia da Córnea/instrumentação , Ceratocone/diagnóstico por imagem , Transtornos da Visão/diagnóstico por imagem , Adolescente , Adulto , Idoso , Criança , Paquimetria Corneana/métodos , Topografia da Córnea/métodos , Progressão da Doença , Humanos , Pessoa de Meia-Idade , Análise de Regressão , Reprodutibilidade dos Testes , Acuidade Visual , Adulto Jovem
17.
Interv Cardiol Clin ; 9(3): 311-319, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32471672

RESUMO

Injection of contrast media is the foundation of invasive and interventional cardiovascular practice. Iodine-based contrast was first used in the 1920s for urologic procedures and examinations. The initially used agents had high ionic and osmolar concentrations, which led to significant side effects, namely nausea, vomiting, and hypotension. Newer contrast agents had lower ionic concentrations and lower osmolarity. Modifications to the ionic structure and iodine content led to the development of ionic low-osmolar, nonionic low-osmolar, and nonionic iso-osmolar contrast media. Contemporary contrast agents are better tolerated and produce fewer major side effects.


Assuntos
Anafilaxia/induzido quimicamente , Anafilaxia/prevenção & controle , Meios de Contraste/efeitos adversos , Meios de Contraste/química , Anafilaxia/epidemiologia , Anafilaxia/fisiopatologia , Procedimentos Cirúrgicos Cardiovasculares/normas , Meios de Contraste/administração & dosagem , Meios de Contraste/história , Técnicas de Diagnóstico Cardiovascular/normas , Feminino , História do Século XX , Humanos , Incidência , Masculino , Estudos Observacionais como Assunto , Concentração Osmolar , Medição de Risco , Procedimentos Cirúrgicos Urológicos/normas
18.
J AOAC Int ; 103(1): 272-277, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31439078

RESUMO

BACKGROUND: The U.S. Pharmacopeia (USP) established microbiological procedures to evaluate nonsterile products and nutritional and dietary supplements for objectionable microorganisms of concern in the industry. A rapid method has been developed to detect the presence of microorganisms based on real-time photometric monitoring of pH, carbon dioxide, or fluorescence indicators within a novel broth/agar combination vial and accompanying reader. OBJECTIVE: To validate the performance of the Neogen Rapid Microbiology System (NRMS) method against the USP reference method for the ability to detect presence or the absence of Escherichia coli, Salmonella, Staphylococcus aureus, and Pseudomonas aeruginosa in nutraceutical and dietary supplements. METHODS: Over 200 samples were evaluated for the presence of objectionable microorganisms. For each specified microorganism, a minimum of 23 matrices were tested uninoculated and with a low-level inoculum of <1-27.4 CFU/g, as paired samples, by NRMS and USP methods. RESULTS: In the four objectionable microorganism categories evaluated, 100% inclusivity, 97-100% exclusivity, 97-100% positive predictivity, 100% negative predictivity, and Kappa Indices of 0.97-1.0 were achieved following ISO 5725-6:1994 standards. CONCLUSIONS: The validation study demonstrates that NRMS is a rapid and effective method to detect objectionable microorganisms in a variety of nutraceutical and dietary supplements. HIGHLIGHTS: A novel method was validated against the relevant USP reference method for the detection of Escherichia coli, Salmonella, Staphylococcus aureus, and Pseudomonas aeruginosa in nutraceutical and dietary supplements. NRMS provided results statistically comparable to the USP reference method within 22 h following primary enrichment compared with 5-7 days by the reference method.


Assuntos
Microbiologia de Alimentos , Salmonella , Suplementos Nutricionais , Escherichia coli , Staphylococcus aureus
19.
Psychophysiology ; 57(3): e13508, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31777970

RESUMO

ERPs in the EEG were scrutinized in learning a complex arm movement sequence with the aim to examine valence effects on processing augmented feedback during practice. Twenty-four healthy subjects practiced one session with 192 feedback trials according to an adaptive bandwidth feedback approach with a high informational level of feedback information (i.e., amplitude and direction of errors). The bandwidth for successful performance (increase of a score for a monetary competition) was manipulated to yield a success rate (positive feedback frequency) of approximately 50% adaptive to the current performance level. This allowed a variation of feedback valence unconfounded by success rate. In line with our hypotheses, the EEG data showed a valence-dependent feedback-related negativity (FRN) and a later fronto-central component at the FCz electrode as well as a P300 component at the Pz electrode. Moreover, the P300 and amplitudes in the FRN time window reduced in the second half of practice but were still dependent on feedback valence. Behavioral adjustments were larger after feedback with negative valence and were predicted by the late fronto-central component. The data support the assumption of feedback valence-dependent modulation of attentional cognitive involvement in motor control and learning.


Assuntos
Potenciais Evocados/fisiologia , Retroalimentação Psicológica/fisiologia , Aprendizagem/fisiologia , Atividade Motora/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
20.
Mar Pollut Bull ; 143: 109-114, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31789144

RESUMO

This paper presents a compilation of data describing interfacial tension between oil and seawater (IFT(oil-water)) as a function of dispersant dosage. The data are from several earlier laboratory studies simulating subsea oil blowouts to evaluate subsea injection of dispersant (SSDI). Three dispersants were tested with four oil types to give a large variation in oil properties (paraffinic, light, waxy and asphaltenic). A general expression for IFT(oil-water) as a function of dispersant dosage is proposed based on the compiled data. IFT(oil-water) versus dosage is needed by algorithms to predict oil droplet sizes from subsea releases. However, such a relationship based on averaged data should be used with care and IFT measurements on the actual oil-dispersant combination should always be preferred.


Assuntos
Poluição por Petróleo , Água do Mar/química , Tensoativos/química , Poluentes Químicos da Água/química , Recuperação e Remediação Ambiental/métodos , Petróleo , Tensão Superficial
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