RESUMEN
Viruses and bacteria, which can rapidly spread through droplets and saliva, can have serious effects on people's health. Viral activity is traditionally inhibited using chemical substances, such as alcohol or bleach, or physical methods, such as thermal energy or ultraviolet-light irradiation. However, such methods cannot be used in many applications because they have certain disadvantages, such as causing eye or skin injuries. Therefore, in the present study, the electrical stimulation method is used to stimulate a virus, namely, coronavirus 229E, and two types of bacteria, namely, Escherichia coli and Staphylococcus aureus, to efficiently reduce their infectivity of healthy cells (such as the Vero E6 cell in a viral activity-inhibition experiment). The infectivity effects of the aforementioned virus and bacteria were examined under varying values of different electrical stimulation parameters, such as the stimulation current, frequency, and total stimulation time. The experimental results indicate that the activity of coronavirus 229E is considerably inhibited through direct-current pulse stimulation with a current of 25 mA and a frequency of 2 or 20 Hz. In addition, E. coli activity was reduced by nearly 80% in 10 s through alternating-current pulse stimulation with a current of 50 mA and a frequency of 25 Hz. Moreover, a self-powered electrical stimulation device was constructed in this study. This device consists of a solar panel and battery to generate small currents with variable frequencies, which has advantages of self-powered and variable frequencies, and the device can be utilized on desks, chairs, or elevator buttons for the inhibition of viral and bacterial activities.
RESUMEN
In this study, we present a new way to predict the Zernike coefficients of optical system. We predict the Zernike coefficients through the function of image recognition in the neural network. It can reduce the mathematical operations commonly used in the interferometers and improve the measurement accuracy. We use the phase difference and the interference fringe as the input of the neural network to predict the coefficients respectively and compare the effects of the two models. In this study, python and optical simulation software are used to confirm the overall effect. As a result, all the Root-Mean-Square-Error (RMSE) are less than 0.09, which means that the interference fringes or the phase difference can be directly converted into coefficients. Not only can the calculation steps be reduced, but the overall efficiency can be improved and the calculation time reduced. For example, we could use it to check the performance of camera lenses.
RESUMEN
The major factors of an illuminative environment are a high rendering index and uniformity. The natural light illumination system (NLIS) is used to guide sunlight for indoor illumination. The NLIS consists of three subsystems: collecting, transmitting, and emitting. Nowadays, a variety of light emitters are available for different illuminative environments. This paper proposes a linear microstructure to diffuse parallel light for indoor illumination. To increase uniformity and promote the illuminative area, the light emitter includes two microstructures for the distribution of light. Finally, the proposed light emitter gives illuminance uniformity and efficiency of 0.55% and 74.18%, respectively.
RESUMEN
This research presents a novel design of the collimator, which uses total internal reflection (TIR), convex, and concave lenses for the natural light illumination system (NLIS). The concept of the NLIS is to illuminate building interiors with natural light, which saves energy consumption. The TIR lens is used to collimate the light, and convex and concave lenses are used to converge the light to the required area. The results have shown that the efficiency in terms of achieving collimated light using the proposed collimator at the output of the light collector is better than that of a previous system without a collimator.
RESUMEN
In developing a daylighting system, the overall system efficiency is crucial. In the daylighting system, whether the light propagates parallel strongly affects the efficiency. In this paper, we simulate a multicurvature lens to collimate rays propagated from different angles. We describe a method based on a freeform microlens array, which increases transmission efficiency. Results show that with the freeform microlens array collimator, the light propagates provide at least 50.26% parallel and the efficiency increases by 24.76%, enhancing the core values of the daylighting system in building illumination.
RESUMEN
Molecular polarization of ferroelectric poly(vinylidene fluoride) (PVDF) is manipulated at the nanometer scale in order to influence the local electronic structure and reactivity at the surface. A direct current voltage, applied through a conductive scanning probe tip, is used to pattern ferroelectric domains in a PVDF thin film, and the polarization direction of these domains influences the kinetics of electron exchange at the surface. By means of a surface photoreduction reaction, which occurs in a metal ion solution under ultraviolet irradiation, metal nanoparticles are deposited in predetermined configurations on polymer surfaces. The photoexcited carriers are generated from defect states within the energy gap of the material, and these gap states are found not only at the interface but throughout the bulk polymer. This represents the first demonstration of ferroelectric nanolithography on an organic substrate and opens the door to applications in organic electronics.
RESUMEN
As endosseous dental implant therapy rapidly becomes the prosthetic standard of care for a vast array of clinical applications, we are faced with the challenge of developing dynamic treatment planning protocols. This paper will discuss the clinical benefits of immediate implants and outline a synthesis of case selection criteria garnered from amongst current immediate implant trends. Our immediate findings are that although implants have become widely accepted despite controversial beginnings and the available literature consistently cites high levels of success (ranging from 94 to 100 percent on average), there is no universally agreed upon case selection criteria. Our principal conclusion is that the high success rate of endosseous implant therapy has yet to achieve wide public acceptance and utilization. Overcoming barriers to public utilization will greatly depend on our ability as dentists to appropriately select cases and deliver treatment in a timely and cost-effective manner. Further, developing case selection criteria for immediate dental implants will help to overcome these barriers by increasing treatment success rates and minimizing treatment cost and time.