120 research outputs found

    Research on the influence, causes and countermeasures of college students' mobile phone dependence

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    Based on the rapid development of Internet technology and the popularity of mobile phone use, there are more problems caused by college students' mobile phone use. This paper analyzes the influence of College Students' mobile phone dependence from two aspects, and states the causes of this phenomenon from both subjective and objective aspects. Finally, it gives the Countermeasures of College Students' mobile phone dependence from five aspects, in order to enable college students to reasonably control the time of using mobile phones, Use mobile phones scientifically

    Wavelength dependence and figures of merit of ultrafast third-order optical nonlinearity of a conjugated 3,3-bipyridine derivative

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    The wavelength dependence and figures of merit of the third-order optical nonlinearity of a conjugated 3,3Ј-bipyridine derivative, a designed nondipolar structure of the donor-acceptor-acceptor-donor type, are reported. Z scans reveal positive nonlinear refractive-index changes for wavelengths longer than the one-photon absorption wavelength. Although the value of nonlinear Kerr coefficient n 2 decreases from 6.0͑Ϯ0.2͒ ϫ 10 Ϫ6 cm 2 ͞GW at 750 nm to 4.6͑Ϯ0.7͒ ϫ 10 Ϫ6 cm 2 ͞GW at 1550 nm, the value of nonlinear absorption ␤ decreases from 0.084 cm͞GW at 750 nm to a negligible value at 1550 nm, giving rise to excellent nonlinearity-to-loss figures of merit at telecommunications wavelengths

    Objective identification and forecast method of PM2.5 pollution based on medium- and long-term ensemble forecasts in Beijing-Tianjin-Hebei region and its surrounding areas

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    Accurate long-term forecasts of PM2.5 pollution are essential to mitigating health risks and formulating pollutant control strategies for decision-makers in China. In this study, an objective identification and forecast method for PM2.5 pollution (OIF-PM2.5) is developed based on medium- and long-term ensemble forecasts of PM2.5 in Beijing-Tianjin-Hebei region and its surrounding areas. The results show that the observed PM2.5 pollution ratio increases with the aggravating PM2.5 pollution. For example, the ratio of meteorological stations with heavy pollution is 4.4 times that of light pollution and 3.9 times that of moderate pollution. In addition, the correlation coefficients between observations and forecasts are above 0.60 for all forecast leading times. Statistical results show that the average accuracy for forecasts with the leading times of 1–3 days, 4–7 days, and 8–15 days are 74.1%, 81.3%, and 72.9% respectively, indicating that the OIF-PM2.5 method has a high reliability in forecasts with the leading times of 1–15 days. The OIF-PM2.5 method is further applied in a severe PM2.5 pollution episode in the December of 2021, and the average forecast precision in forecasts with the leading times of 6–8 days reaches as high as 100%, showing a certain reference value for PM2.5 forecasts

    Preliminary study of improving immune tolerance in vivo of bioprosthetic heart valves through a novel antigenic removal method

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    The durability of bioprosthetic heart valves is always compromised by the inherent antigenicity of biomaterials. Decellularization has been a promising approach to reducing the immunogenicity of biological valves. However, current methods are insufficient in eliminating all immunogenicity from the biomaterials, necessitating the exploration of novel techniques. In this study, we investigated using a novel detergent, fatty alcohol polyoxyethylene ether sodium sulfate (AES), to remove antigens from bovine pericardium. Our results demonstrated that AES treatment achieved a higher pericardial antigen removal rate than traditional detergent treatments while preserving the mechanical properties and biocompatibility of the biomaterials. Moreover, we observed excellent immune tolerance in the in vivo rat model. Overall, our findings suggest that AES treatment is a promising method for preparing biological valves with ideal clinical application prospects

    Microfabrication and Applications of Opto-Microfluidic Sensors

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    A review of research activities on opto-microfluidic sensors carried out by the research groups in Canada is presented. After a brief introduction of this exciting research field, detailed discussion is focused on different techniques for the fabrication of opto-microfluidic sensors, and various applications of these devices for bioanalysis, chemical detection, and optical measurement. Our current research on femtosecond laser microfabrication of optofluidic devices is introduced and some experimental results are elaborated. The research on opto-microfluidics provides highly sensitive opto-microfluidic sensors for practical applications with significant advantages of portability, efficiency, sensitivity, versatility, and low cost

    Tapered fiber Mach–Zehnder interferometer for simultaneous measurement of refractive index and temperature

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    An approach to achieve simultaneous measurement of refractive index and temperature is proposed by using a Mach-Zehnder interferometer realized on tapered single-mode optical fiber. The attenuation peak wavelength of the interference with specific order in the transmission spectrum shifts with changes in the environmental refractive index and temperature. By utilizing S -band and C/L -band light sources, simultaneous discrimination of refractive index and temperature with the tapered fiber Mach-Zehnder interferometer is demonstrated with the corresponding sensitivities of -23.188 nm/RIU (refractive index unit) and 0.071 nm/ °C, and -26.087 nm/RIU (blueshift) and 0.077 nm/°C (redshift) for the interference orders of 169 and 144, respectively

    Laser processing of silicon at submicron scale using photochromic films

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    Laser fabrication at submicron scale is experimentally demonstrated with the nonlinear optical switching effect of photochromism. The effect, which is a result of change in the optical properties of the photochromic material between the open-ring and closed-ring isomers during the photoisomerization, effectively reduces the laser beam size. The ultrafast response of the molecular photocyclization and cycloreversion reactions at a time scale of a few picoseconds ensures the instantaneous realization of the effect. Utilizing a photochromic film of cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl) ethane as the mask layer, laser processing of a silicon wafer demonstrated submicron scale feature size with improved surface quality as compared to the smallest features achievable using direct laser ablation without the photochromic film.Peer reviewed: YesNRC publication: Ye

    Data Mining for Adverse Events Signals of Acalabrutinib Based on FAERS Database

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    Objective To explore the potential adverse reactions of acalabrutinib by mining and analyzing the pharmacovigilance signal of acalabrutinib, to provide a reference for clinically safe and rational drug use. Methods Data related to acalabrutinib in the FAERS database were searched, and pharmacovigilance signals were obtained using the disproportionality measurement. Results A total of 3, 155 reports of adverse events with acalabrutinib as the primary suspected drug were extracted, and 73 warning signals were detected involving 15 system organ classifications, 36 of which were not included in the drug instructions of acalabrutinib. The strong signals of acalabrutinib were mainly concentrated in various inflammatory and bleeding, anemia, contusion, atrial fibrillation, and so on. The largest number of system organ classification signals were focused on the blood and lymphatic system disorders, investigations, infections, and so on. In addition, the drug may cause tachycardia, brittle nails, and other warning signs. Through further analysis of gender-related adverse events, there were a total of 49 high-risk signals with gender differences found. Herein, male patients should pay attention to adverse reactions in bleeding, heart, urinary system, hypertension, and so on; meanwhile, female patients should be alert to adverse reactions in liver function, skin inflammation, and so on. Conclusion A total of 36 drug warning signs that are not mentioned in the instructions for acalabrutinib are mined using FAERS, and blood, infection, and cardiac toxicity require special attention. Thus, these signals should be detected promptly for effective prevention in clinical medication to reduce the risk of medication use for patients
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