RESUMO
Epidemiological evidence showed that serum high perfluorooctane sulfonate (PFOS) levels are associated with multiple eye related diseases, but the potential underlying molecular mechanisms remain poorly understood. Zebrafish and photoreceptor cell (661w) models were used to investigate the molecular mechanism of PFOS induced eye development defects. Our results showed a novel molecular mechanism of PFOS-induced inflammation response-mediated photoreceptor cell death associated with eye development defects. Inhibition of Caspase-8 activation significantly decreased photoreceptor cell death in PFOS exposure. Mechanistically, Toll-like receptor 4 (TLR4) mediates activation of Caspase-8 promote activation of NLR family pyrin domain-containing 3 (NLRP3) inflammasome to elicit maturation of interleukin-1 beta (IL-1ß) via Caspase-1 activation, facilitating photoreceptor cell inflammation damage in PFOS exposure. In addition, we also made a novel finding that Caspase-3 activation was increased via Caspase-8 activation and directly intensified cell death. Our results show the important role of Caspase-8 activation in PFOS induced eye development defects and highlight Caspase-8 mediated activation of the NLRP3 inflammation triggers activation of Caspase-1 and promote the maturation of IL-1ß in retinal inflammatory injury.
Assuntos
Ácidos Alcanossulfônicos , Caspase 8 , Fluorocarbonos , Inflamassomos , Larva , Proteína 3 que Contém Domínio de Pirina da Família NLR , Peixe-Zebra , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamassomos/metabolismo , Caspase 8/metabolismo , Caspase 8/genética , Ácidos Alcanossulfônicos/toxicidade , Fluorocarbonos/toxicidade , Larva/efeitos dos fármacos , Interleucina-1beta/metabolismo , Olho/efeitos dos fármacos , Poluentes Químicos da Água/toxicidadeRESUMO
Volume Bragg grating is one-step fabricated with femtosecond laser direct-writing technology inside a high nonlinearity chalcogenide glass of As2S3. As the generated femtosecond laser filamentation effect could combined with the cylindrical lens focusing method, a two-dimensional refractive index change interface could spontaneously grow along the incident direction with either the laser pulse energy or number increasing. A number of two-dimensional refractive index change interfaces are periodically arranged to stack into a volume Bragg grating. Through periodically moving the sample stage, a grating of 2 mm × 2 mm × 1.7 mm can be fabricated in 15 minutes. And the maximum diffraction efficiency of grating reached 95.49% under the optimal parameters. This study provides a new processing strategy for femtosecond laser direct-writing volume Bragg grating with high processing efficiency and excellent structural performance.
RESUMO
Our objective was to determine effects of supplemental dietary riboflavin on meat quality, antioxidant capacity, fatty acid composition, lipidomic, volatilomic, and proteomic profiling of duck breast muscle. The results showed that dietary riboflavin supplementation significantly increased growth performance, breast meat yield, intramuscular fat content, polyunsaturated fatty acid (PUFA), n3-PUFA, n6-PUFA, redness (a*), and pH24h, but decreased lightness (L*) and yellowness (b*). Furthermore, riboflavin supplementation significantly improved muscle antioxidant capacity based on various biochemical parameters. Lipidomic and volatilomic analyses revealed that riboflavin supplementation markedly increased breast meat phosphatidylglycerol and coenzyme Q contents and two favourable key odorants, citronellyl acetate and 3-(methylthio)-propanal. Proteomics analyses confirmed that riboflavin supplementation activated mitochondrial aerobic respiration, including fatty acid beta oxidation, the tricarboxylic acid cycle, and oxidative phosphorylation. In conclusion, supplementing duck diets with riboflavin enhanced breast meat quality, attributed to increases in antioxidant capacity and mitochondrial functions.
RESUMO
With the outbreak of COVID-19, organizations have increased non-face-to-face work. This study aims to examine how leaders' influence tactics affect employees' psychological state and job performance in a non-face-to-face work (telework) setting. Moreover, based on substitutes for leadership theory, the study proposes that teleworkers' perceived organizational support moderates the relationship between leaders' influence tactics and their job stress in telework settings. We collected data via time-lagged surveys among 208 full-time employees in South Korean organizations that began teleworking after the outbreak of the COVID-19 pandemic. The results showed that leaders' soft tactics (i.e., behaviors used to elicit the followers' voluntary acceptance of a request) and rational tactics (i.e., behaviors that exert influence by providing empirical evidence based on reason or logic) significantly reduced teleworkers' job stress, which in turn lowered their turnover intention and increased their task performance. Moreover, these tactics and teleworkers' perceived organizational support interact to influence the workers' job stress. By examining how leaders' influence tactics affect teleworkers' psychological stress, task performance, and turnover intention in the wake of the COVID-19 pandemic, this study theoretically broadens the influence tactics literature, which previously focused primarily on face-to-face workers. The study concludes with a discussion about the implications of findings and limitations, along with areas for future research.
RESUMO
Self-assembled nanogratings, inscribed by femtosecond laser writing in volume, are demonstrated in multicomponent alkali and alkaline earth containing alumino-borosilicate glasses. The laser beam pulse duration, pulse energy, and polarization, were varied to probe the nanogratings existence as a function of laser parameters. Moreover, laser-polarization dependent form birefringence, characteristic of nanogratings, was monitored through retardance measurements using polarized light microscopy. Glass composition was found to drastically impact the formation of nanogratings. For a sodium alumino-borosilicate glass, a maximum retardance of 168â nm (at 800 fs and 1000 nJ) could be measured. The effect of composition is discussed based on SiO2 content, B2O3/Al2O3 ratio, and the Type II processing window is found to decrease as both (Na2O + CaO)/Al2O3 and B2O3/Al2O3 ratios increase. Finally, an interpretation in the ability to form nanogratings from a glass viscosity viewpoint, and its dependency with respect to the temperature, is demonstrated. This work is brought into comparison with previously published data on commercial glasses, which further indicates the strong link between nanogratings formation, glass chemistry, and viscosity.
RESUMO
Microchannels fabricated by femtosecond laser-assisted chemical etching are of great use in biochemical analysis. In this paper, we study the morphology change of etched microchannels in fused silica by controlling the laser scan speed, and we find a significant difference between the chemical etched length and volume. The fabricated microchannels would gradually become tapered along the scan direction, which influences the flow of the hydrofluoric (HF) reagent and the etching rate. As a result, the difference ratios of the etched length and volume, respectively, reach -5.56% and -41.83% followed by the scan speed increasing from 5 to 200 µm/s. Microchannels with polarization independence and better aspect ratio could be obtained in a high-speed-scan mode. We suggest that laser-induced structural transformation from interconnected microcracks to nanogratings could be responsible for this change. Aforementioned results offer a feasible approach to achieve polarization-independent microchannels, which is in favor of accelerating the fabrication of three-dimensional microfluidic devices.
RESUMO
Multiple self-construction behavior of cyclic oligoesters is described. Rigid braces and elastic hinges are periodically incorporated into these cyclomers, which enables these rings to form various topological frameworks, such as holes, caves or cages with different sizes and shapes, through self-folding. Among them, the cave-type cyclomer self-assembles into nanotunnels and then forms porous materials via self-packing of these tunnels. This discovery provides a new perspective for the construction of novel materials aided by multiple supramolecular effects. In this work, the simplest rigid brace components and ones with soft hinges were chosen to construct cyclomers to confirm the supramolecular strategy.
Assuntos
Braquetes , PorosidadeRESUMO
To meet the energy demand in remote areas of western China, a small modular fluoride-salt-cooled high-temperature reactor will be deployed there. The design of this reactor needs an application target image, including the power, lifetime, size, weight, and environmental restrictions. This paper analyzes the energy demand in northwest China to find the possible application scenarios and regions of this reactor. Then according to typical application scenarios, the power requirements of the reactor and the environment and transportation (size and weight) restrictions that need to be adapted can be obtained. The application target image of this reactor would be: a) the single unit capacity of 50MWe; b) the lifetime of at least 60 years; c) the length of less than 15.5 m, the diameter of less than 3.88 m, and weight of less than 60 tons; d) the adaptability to the severe climate and environment in the west, such as cold winter, deep-frozen soil layer, strong wind, arid environment, and complex terrain; e) the site selection to avoid geological disasters, such as landslides, collapses, torrents, mudslides, and ground fissures.
RESUMO
In this study, Yb/Al/Ge co-doped silica fiber core glasses with different GeO2 contents (0-6.03 mol%) were prepared using the sol-gel method combined with high-temperature sintering. The absorption, fluorescence, radiation-induced absorption, continuous-wave electron paramagnetic resonance spectra, and fluorescence decay curves were recorded and analyzed systematically before and after X-ray irradiation. The effects of GeO2 content on the valence variations of Yb3+/Yb2+ ions, spectral properties of Yb3+ ions, and radiation resistance of Yb/Al/Ge co-doped silica glasses were systematically studied. The results show that even if the GeO2 content of the sample is relatively low (0.62 mol%), it can inhibit the generation of Yb2+ ions with slight improvement in the spectral properties of Yb3+ ions in the pristine samples and effectively improve its radiation resistance. Direct evidence confirms that the generation of trapped-electron centers (Yb2+/Si-E'/Al-E') and trapped-hole centers (Al-OHC) was effectively inhibited by Ge co-doping. This study provides a theoretical reference for the development of high-performance, radiation-r esistant Yb-doped silica fibers.
RESUMO
Good heat dissipation performance of aero-engine an effectively improve the service performance and service life of aero-engine. Therefore, this paper studies the machining method of cooling holes of high-temperature existent material GH 4169 for aero-engine innovatively puts forward the mask electrochemical machining method of cooling holes and explores the entrance morphology and taper formation law of the hole structure of high-temperature resistant material GH 4169. The mathematical model of anode dissolution of cooling holes in ECM is established, and the influence of voltage and electrolyte flow rate on cooling holes in ECM is analyzed. Compared with the mask-less electrochemical machining, the inlet radius of cooling holes in mask electrochemical machining is reduced by about 16.0% and the taper is reduced by 52.8% under the same machining parameters, which indicates that the electrochemical machining efficiency of mask is higher and the machining accuracy is better. Experiments show that the diameter of the mask structure improves the accuracy of the inlet profile of the cooling hole in the ECM. The diameter of the mask increases from 2 mm to 2.8 mm, and the inlet radius of the cooling hole increased from 1.257 mm to 1.451 mm When the diameter of the mask is 2.2 mm, the taper of the cooling hole decreased by 53.4%. The improvement effect is best, and the thickness of the mask has little influence on the forming accuracy of the cooling hole.
RESUMO
A high phosphorus Er3+/Yb3+ co-doped silica (EYPS) fiber core glass was prepared using the sol-gel method combined with high-temperature sintering. The absorption spectra, emission spectra, and fluorescence decay curves were measured and compared in temperatures ranging from 300 to 480 K. Compared to 915 and 97x nm, the absorption cross-section at ~940 nm (~0.173 pm2) demonstrates a weaker temperature dependence. Hence, the 940 nm pump mechanism is favorable for achieving a high-power laser output at 1.5 µm. Additionally, the double-exponential fluorescence decay of Yb3+ ions and the emission intensity ratio of I1018nm/I1534nm were measured to evaluate the energy transfer efficiency from Yb3+ ions to Er3+ ions. Through the external heating and active quantum defect heating methods, the emission intensity ratios of I1018nm/I1534nm increase by 30.6% and 709.1%, respectively, from ~300 to ~480 K. The results indicate that the temperature rises significantly reduce the efficiency of the energy transfer from the Yb3+ to the Er3+ ions.
RESUMO
In this paper, the forming mechanism of cooling hole electrolytic machining is studied using multi-physical field coupled simulation and experimental observation. A multi-physical field coupled simulation model was established to obtain the gas-liquid two-phase distribution law inside the machining gap, and a mathematical model of gas-liquid two-phase flow was established to analyze the change law of the size and morphology of cooling hole electrolytic machining under different process parameter conditions. The simulation and experimental results show that the size of the inlet of the cooling hole is larger, the size of the outlet is smaller, and the middle section is more stable; machining voltage and electrode feed speed have a significant influence on the size and shape of heat dissipation holes. Compared with the experimental data, simulation accuracy is good.
RESUMO
The temporal chirp of single femtosecond (fs) pulses will affect the laser-induced ionization process. By comparing the ripples induced by negatively and positively chirped pulses (NCPs and PCPs), the growth rate showed a significant difference, resulting in a depth inhomogeneity of up to 144%. A carrier density model tailored with temporal characteristics showed that NCPs could excite a higher peak carrier density, contributing to a highly efficient generation of surface plasmon polaritons (SPPs) and overall advancement of the ionization rate. Such distinction originates from their contrary incident spectrum sequences. Current work reveals that temporal chirp modulation can control the carrier density in ultrafast laser-matter interaction, which possibly brings an unusual acceleration for surface structure processing.
RESUMO
IMPORTANCE: The conventional 2.2-mm clear corneal incision is relatively narrow compared with the sleeves of Phaco handpieces, resulting in friction at the incision site and increased risk of incision-related Descemet membrane detachment (DMD). The modified 2.2-mm incision only enlarged internal width to 3.0 mm, forming a trapezoid incision shape, which may reduce the friction of surgical instruments and decrease the risk of incisional DMD. OBJECTIVE: To compare the incidence of incision-related DMD between eyes undergoing modified vs conventional 2.2-mm incision phacoemulsification for hard nuclear age-related cataract. DESIGN, SETTING, AND PARTICIPANTS: This double-masked, parallel randomized clinical trial was conducted from July 22, 2019, to January 22, 2020, at Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China. The study included patients with age-related cataract and nuclear opalescence grade of 4.0 or greater based on the Lens Opacities Classification System III. Patients were enrolled in this study according to the following inclusion criteria: (1) age between 65 to 90 years; (2) pupil size of 6 mm or greater after dilation; (3) Lens Opacities Classification System III nuclear opalescence grade of 4.0 or more; and (4) corneal endothelial cell density greater than 1500 cells/mm2. INTERVENTIONS: Modified (enlarged internal width to 3.0 mm) or conventional 2.2-mm incision phacoemulsification with intraocular lens implantation. MAIN OUTCOMES AND MEASURES: Incidence of incision-related DMD at postoperative day 1. RESULTS: A total of 130 eyes of 130 patients were randomized into the conventional group (n = 65) or the modified group (n = 65). The mean (SD) age of participants was 74.5 (5.9) years and 74.3 (6.0) years in the conventional and modified groups, respectively. A total of 26 participants in the conventional group (40%) and 27 in the modified group (42%) were men. Compared with eyes in the conventional group, the incidence of DMD in eyes in the modified group was significantly lower at postoperative day 1 (difference, 26.15; 95% CI, 9.60-42.71; P = .003). The difference at postoperative day 7 was 16.92 (95% CI, 2.91-30.94; P = .02). The length of DMD (postoperative day 1: difference, 0.188; 95% CI, 0.075-0.301; P = .002) and maximal corneal thickness at incision site (postoperative day 1: difference, 0.032; 95% CI, 0.006-0.057; P = .02; postoperative day 7: difference, 0.019; 95% CI, 0.003-0.035; P = .02) were lower in the modified group, while visual quality parameter modulation transfer function (postoperative day 1: difference, -0.033; 95% CI, -0.064 to -0.001; P = .04) was higher. No difference was observed between the 2 groups in best-corrected visual acuity, central corneal endothelium loss, or surgically induced astigmatism at any follow-up time. There were no intraoperative complications in the 2 groups. CONCLUSIONS AND RELEVANCE: These findings suggest that modified 2.2-mm trapezoid incision phacoemulsification reduces the incidence of DMD for hard nuclear age-related cataract at postoperative day 1 and might be considered in patients at high risk of incision-related DMD, although the clinical relevance cannot be determined with certainty from this trial. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04014699.
Assuntos
Catarata , Facoemulsificação , Idoso , Idoso de 80 Anos ou mais , Catarata/epidemiologia , Catarata/etiologia , Lâmina Limitante Posterior/cirurgia , Feminino , Humanos , Incidência , Masculino , Facoemulsificação/efeitos adversos , Facoemulsificação/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Acuidade VisualRESUMO
This paper presents a simulation and experimental study of the structure of small holes in GH4169 alloy electrolytic ally processed by tube electrodes with different characteristic power sources. It analyzes the multi-physical field coupling relationship of flow, temperature, and electric fields within the interstitial space. The results indicate that the tube electrode electrolytic processing of the GH4169 alloy small hole structure with a pulsed power supply has more uniform temperature and current density distribution within the gap, which is beneficial to the processing accuracy and smoothness of the small hole structure. Meanwhile, SEM was used to analyze the microscopic morphology of the electrode end surface during short-circuiting, and it was concluded that as the processing continued, the electrode end surface gradually produced a non-metallic oxide layer, which destroyed the electric field of the gap and affected the processing stability. The use of high-frequency positive and negative pulse power can effectively avoid the generation of a non-metallic oxide layer. Through the combination of simulation analysis and experimental verification, it is concluded that increasing electrolyte pressure in stages can effectively improve machining accuracy and stability. The interstitial current increases as the feed rate of the tool electrode increases, and the diameter of the machined small hole decreases as it increases.
RESUMO
Electrical parameters of the power supply are significant factors affecting the accuracy and stability of the electrochemical machining (ECM). However, the electric field, flow velocity and temperature in the machining area are difficult to measure directly under the influence of the power supply. Therefore, taking the film cooling hole as an example, the multi-physics coupling simulation analysis of the ECM is performed on the basis of Faraday's law and fluid heat transfer mathematical model. The machining characteristics of the direct current and pulse ECM are compared through simulation. The results show that the pulse ECM improves the distribution of temperature and current density in the machining area. The period has little effect on the temperature, current density and side removal rate. The side removal rate increases with the increase of the duty ratio and lateral gap. Increasing of the duty ratio and decreasing of the lateral gap will increase the temperature and current density. Increasing the inlet pressure accelerates the frequency of renewal of heat and electrolysis products, which can reduce the single side gap. The experience of the ECM holes verifies the results of the simulation. The accuracy and stability of the ECM of holes are enhanced by optimizing the duty ratio, lateral gap and inlet pressure.
RESUMO
Purpose: The purpose of this study was to evaluate the effect of high myopia on anterior angle change after pharmacologic mydriasis in patients with cataract using swept-source anterior segment optical coherence tomography (SS-ASOCT). Methods: This prospective cross-sectional study continuously recruited patients with cataract aged 40 years and older during the period August 2019 to August 2020. The anterior segment parameters, including central corneal thickness (CCT), anterior chamber depth (ACD), angle opening distance (AOD), angle recess area (ARA), trabecular iris space area (TISA), trabecular-iris angle (TIA), angle to angle width (ATA), and anterior chamber volume (ACV), were obtained using SS-ASOCT at baseline and 30 minutes after mydriasis. Regression analyses were performed to identify the factors related to the relative change of AOD500 (ΔAOD500). Results: A total of 938 patients (938 eyes) were included. The AOD500 decreased from 0.46 ± 0.22 mm to 0.40 ± 0.19 mm, with percent ΔAOD500 of -13.59% ± 37.73% (P = 0.005). The patients with high myopia had a smaller reduction of anterior angle parameters, with a percent ΔAOD500 of -22.74% ± 58.09%% in non-high myopic eyes and -0.84% ± 45.47% in high myopic eyes (P < 0.001). The stepwise multivariate regression demonstrated that the smaller reduction of AOD500 were independently associated with younger age (coefficient = -2.11, 95% confidence interval [CI] = -2.59 to -1.64, P < 0.001), presence of high myopia (coefficient = 15.35, 95% CI = 3.63 to 27.07, P = 0.010), greater baseline TISA500 (coefficient = 60.78, 95% CI = 8.75 to 112.82, P = 0.022), and ATA (coefficient = 11.21, 95% CI = 4.53 to 17.89, P = 0.001). Conclusions: The anterior chamber angle decreased after pharmacologic mydriasis in these patients with cataract. Angle shallowing after pharmacologic mydriasis was significantly less pronounced in high myopic eyes than in non-high myopic eyes. Translational Relevance: These findings are informative for the relative less risk of angle-closure glaucoma in highly myopic eyes.
Assuntos
Catarata , Midríase , Miopia , Adulto , Catarata/induzido quimicamente , Estudos Transversais , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Tomografia de Coerência ÓpticaRESUMO
Importance: Incision-related Descemet membrane detachment (DMD) is a common complication of cataract surgery. Most postoperative severe DMD that leads to corneal decompensation originates from intraoperative incision-related DMD. It is important to determine the incidence, extent, and associated risk factors of intraoperative DMD at each step of surgery to help in formulating precise and effective prevention strategies. Objectives: To investigate the intraoperative development of incision-site DMD associated with a 2.2-mm clear corneal incision during cataract surgery and to analyze its associated factors. Design, Setting, and Participants: In this case series, consecutive, prospectively enrolled 133 patients with cataract 50 to 90 years of age (133 eyes) undergoing coaxial 2.2-mm clear corneal microincision phacoemulsification with intraocular lens (IOL) implantation between January 1 and March 31, 2019, at Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China, were studied. Exposures: Coaxial 2.2-mm clear corneal microincision phacoemulsification with IOL implantation. Main Outcomes and Measures: Real-time incidence and extent of intraoperative incision-related DMD at each step of surgery. Results: Among 133 patients with cataracts (mean [SD] age, 72.3 [8.1] years; 77 [57.9%] female), DMD was encountered in 125 eyes (94.0%), occurring at the following steps: capsulorrhexis (2 [1.6%]), hydrodissection (7 [5.6%]), phacoemulsification (69 [55.2%]), irrigation-aspiration (44 [35.2%]), and IOL implantation (3 [2.4%]). The extent of DMD increased during the operation (mean [SD] difference between final and initial relative DMD length, 22.8% [1.4%]; 95% CI, 20.0-25.6; P < .001). Associations for the extent of DMD found in multivariate stepwise analyses included time of ultrasonography (ß = 0.34; 95% CI, 0.17-0.50; P < .001), equivalent mean ultrasonic power (ß = 87.8; 95% CI, 19.1-156.4; P = .01), and the presence of DMD at the anterior and posterior wound margins (coefficient = 16.7; 95% CI, 6.4-26.9; P = .002). Conclusions and Relevance: The results of this case series suggest that friction of surgical instruments has the greatest association with incisional DMD. Decreasing ultrasonic energy and phacoemulsification time may reduce the severity of incisional DMD.