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Viral infections have become an important public health issue in South America during the past 2 decades. Outbreaks of arboviral disease, such as dengue, chikungunya, Zika, and yellow fever, have [...]

Graphene oxide (GO) addition to epoxy can improve various properties provided that the GO features, dispersion and interaction with epoxy are optimized. Herein, the challenge of improving the hydrophobicity, flexural behavior and wear resistance of an epoxy coating on steel substrate was addressed by GO incorporation. Three GO concentrations were tested in the epoxy system (0.1, 0.25, and 0.50% m/m), and nanocomposites were prepared via roller mill. An increase in the thermal stability of the pure epoxy by 23°C was observed for the nanocomposites as a function of GO incorporation. XPS analyses were carried out to study the interaction between DGEBA and GO, and the results show that a covalent link was formed between GO and epoxy. The wettability test showed an increase of 26° in the contact angle while the behavior of the system from mechanical bending tests showed gains of 52% in the energy to fracture for the sample containing 0.5 wt.% GO with respect to the neat epoxy. The wear of the coatings showed a 31% decrease in the wear coefficient of the nanocomposite compared to the reference. The set of results reported in the present work pointed to the epoxy/GO coating as promising in terms of hydrophobicity and wear properties. [ABSTRACT FROM AUTHOR]

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Background: Optic disc drusen (ODD) are calcified deposits in the prelaminar portion of the optic nerve head. Although often asymptomatic, these deposits can cause progressive visual field defects and vision loss. The purpose of this study was to evaluate rates of functional loss in eyes with ODD and to investigate risk factors associated with rates of visual field progression. Methods: This was a retrospective cohort study including 65 eyes of 43 patients with ODD from the Duke Ophthalmic Registry. All eyes had at least 12 months of follow-up and at least 3 reliable standard automated perimetry (SAP) tests. Linear mixed models were used to estimate rates of SAP mean deviation (MD) loss over time. Univariable and multivariable models were used to assess the effect of clinical variables and intraocular pressure (IOP) on rates of change. Results: Subjects were followed for an average of 7.6 ± 5.3 years. The mean rate of SAP MD change was 20.23 ± 0.26 dB/year, ranging from 21.19 to 0.13 dB/year. Fifty-seven eyes (87.7%) had slow progression (slower than 20.5 dB/ year), 6 eyes (9.2%) had moderate progression (between 20.5 dB/year and 21 dB/year), and 2 eyes (3.1%) had fast progression (faster than 21 dB/year). In multivariable models, older age and worse SAP MD at baseline were significantly associated with faster rates of change. Mean IOP was not associated with faster rates of MD change in both univariable and multivariable analyses. Conclusions: Most eyes with ODD had slow rates of visual field loss over time. Age and baseline severity were significantly associated with faster rates of visual field loss. [ABSTRACT FROM AUTHOR]

Background/aims To evaluate the association between statin use and rates of standard automated perimetry (SAP) and retinal nerve fibre layer (RNFL) change in patients with glaucoma and glaucoma suspects. Methods This retrospective cohort study included subjects from the Duke Glaucoma Registry with primary open-angle glaucoma and glaucoma suspects. Subjects were assigned to groups according to history of statin use. Rates of change in SAP mean deviation (MD) and spectral-domain optical coherence tomography (SD OCT) RNFL thickness over time were estimated using linear mixed models and compared in the statin versus control groups. The effect of duration of statin use was also assessed. Patients with glaucoma versus suspects were analysed separately. Analyses were adjusted for potential confounding factors of age, gender, race, intraocular pressure and follow-up time. Results The study included 10 049 SAP tests and 14 198 SD OCT tests from 3007 eyes (1978 patients) followed for an average of 4.7±2.0 years. Of these, 775 subjects (1179 eyes) had a history of statin use. No difference in rates of change was seen between the statin versus control groups for MD (-0.07±0.16 dB/year vs -0.07±0.15 dB/year; p=0.873, respectively) or RNFL thickness (-0.70±0.60 µm/year vs -0.70±0.61 µm/year; p=0.923, respectively). Multivariable models controlling for potential confounders showed no significant association between duration of statin use and rates of MD or RNFL thickness change. Conclusions We did not find a statistically significant association between statin use or duration of statin use and rates of structural and functional change in those with glaucoma or glaucoma suspects. [ABSTRACT FROM AUTHOR]

De acordo com Jennifer Lackey (2007), deve-se asserir que p somente se (i) é razoável acreditar que p e (ii) se alguém asseriu que p, afirmaria que p pelo menos em parte porque é razoável acreditar que p. Como dados para essa norma de asserção, Lackey apela à intuição de que, nos casos de afirmação altruísta, os agentes afirmam com propriedade epistêmica algo que não acreditam. Se essa norma de afirmação fosse verdadeira, então ela explicaria por que as afirmações altruístas são epistemicamente apropriadas. Neste trabalho, oferecemos uma reductio ad absurdum desse ponto de vista. O resultado é que os asserções altruístas não são epistemicamente apropriados