The Multi-shadow Analysis of LED Secondary Optics

AbstractDue to these advantages, small size, low heat radiation, long life time, and high luminous efficiency, the light-emitting diodes (LEDs) have been used widely to the varied lighting in recent years. However, the LEDs have the higher intensity of light in central region and the scattering in the surrounding during lighting, so it is necessary to modify the LED projection by the secondary optical lens. The extra secondary optical lens can enhance the light collection efficiency of LED, but it will readily induce the multi-shadow phenomenon during lighting, which has a significant impact on the human vision. In this study, the LED illumination module with/without secondary optical lens, total internal reflected (TIR) lens or reflection mirror cup, can be simulated by the Apilux(R) optical software. The result indicates that the approach can identify the level of multi-shadow images according to the deviations in light intensity, and will be new performance criteria of LEDs for users

Deltex1 Is a Target of the Transcription Factor NFAT that Promotes T Cell Anergy

SummaryThe molecular process underlying T cell anergy is incompletely understood. Deltex1 (DTX1) is a Notch target with unknown physiological function. Here we show that Dtx1 was a transcription target of nuclear factor of activated T cells (NFAT) and participated in T cell anergy. DTX1 protein was upregulated during T cell anergy, and transgenic expression of Dtx1 attenuated T cell activation. DTX1 inhibited T cell activation by both E3-dependent and E3-independent mechanisms. In addition, DTX1 suppressed T cell activation in the absence of its Notch-binding domain. Importantly, DTX1 regulated the expression of two anergy-associated molecules, growth arrest and DNA-damage-inducible 45 β (Gadd45β) and Cbl-b. DTX1 interacted with early growth response 2 (Egr-2) for optimum expression of Cbl-b. Furthermore, deficiency of DTX1 augmented T cell activation, conferred resistance to anergy induction, enhanced autoantibody generation, and increased inflammation. DTX1 therefore represents a component downstream of calcium-NFAT signaling that regulates T cell anergy

Designing a video laryngoscope imaging system with a 7mm blade for neonatal patients

When a newborn infant has been pushed from the birth canal due to ventilation failure while using a resuscitation mask, the doctor must implement infant intubation and other emergency steps to keep the baby alive. However, due to the excessively small mouth area of a newborn or premature infant, the doctors are unable to view the glottis entrance, which can lead to either a failed intubation or longer intubation time, thereby resulting in either a drop in oxygen levels or a rise in intrathoracic pressure. Although the normal video laryngoscope with a 12mm metal blade certainly improves this type of difficult intubation, nevertheless, doctors often complain that the depth of field (DOF) is insufficient and the width of the blade is too wide when performing intubation on neonatal patients. Therefore, this study aims to develop two modules of infant’s video laryngoscope, an ultra-thin 7mm metal blade and an optical imaging system, the core technology of which includes an optical design of a 2.5mm lens and verifications of imaging quality. In order to allow physicians to determine the infant’s airway position immediately and to avoid the binocular disparity from a physician while giving intubation, this study has simulated the optical properties of monolithic lenses while designing the imaging system, allowing the doctor to have a clearer and undistorted image within the field of view

AZO-Based ZnO Nanosheet MEMS Sensor with Different Al Concentrations for Enhanced H₂S Gas Sensing

The properties of H2S gas sensing were investigated using a ZnO nanostructure prepared with AZO (zinc oxide with aluminium) and Al surfaces which were developed on a MEMS (Micro Electromechanical System) device. Hydrothermal synthesis was implemented for the deposition of the ZnO nanostructure. To find the optimal conditions for H2S gas sensing, different ZnO growth times and different temperatures were considered and tested, and the results were analysed. At 250 °C and 90 min growth time, a ZnO sensor prepared with AZO and 40 nm Al recorded an 8.5% H2S gas-sensing response at a 200 ppb gas concentration and a 14% sensing response at a gas concentration of 1000 ppb. The dominant sensing response provided the optimal conditions for the ZnO sensor, which were 250 °C temperature and 90 min growth time. Gas sensor selectivity was tested with five different gases (CO, SO2, NO2, NH3 and H2S) and the sensor showed great selectivity towards H2S gas

Ultraviolet Laser Sintering of Printed Nickel Oxide Nanoparticles for Thin-Film Thermistor via Aerosol Jet Printing Technology

In this study, nickel oxide (NiO) thin films were printed by an aerosol jet printer, which is capable of fabricating thin films on the curve substrate via air stream. To approach high efficiency fabricating thin film thermistors in small batch sizes, the printed NiO nanoparticle thin films were sintered by using a 355 nm wavelength ultraviolet (UV) laser; this novel fabrication method reduced several steps of the conventional manufacturing process of the thermistor. Compared with furnace heat treatments of the NiO thermistor in previous studies, the UV laser sintering not only significantly improved the electrical properties but decreased the treatment time from an hour to a second. Since the resistance declined, the thermistor has been operated at an ambient temperature, which provides ready measurement. The resistance and morphology of the thin films were analyzed for evaluating the effect of the laser treatment. To identify the proper UV laser parameters, three laser parameters, including laser output energy, frequency, and scanning speed, were studied. Due to the laser-sintering parameters, namely, 2 W, 150 mm/s, 90 kHz, and a B value of 4683 K, the resistance has been reduced from 106.8 MΩ to 6.15 MΩ at 100 °C. The experiments exhibited a series of analyses for sintering states and defects of printed NiO nanoparticle thin film, which were sintered by UV laser. For NiO nanoparticles, UV laser has higher absorption energy than that of other wavelength lasers, when excess laser output was applied to the NiO thin film, cracks were observed on the surface. It was found that the crystal plane distances were not affected by recrystallization, but the cracks were based on the XRD analysis. Based on the analysis, there were obvious regional compressive stains before the appearance of cracks, and the uneven shrinking strains caused the cracks on the surface as energy irradiation increased

Ultraviolet Laser Sintering of Printed Nickel Oxide Nanoparticles for Thin-Film Thermistor via Aerosol Jet Printing Technology

In this study, nickel oxide (NiO) thin films were printed by an aerosol jet printer, which is capable of fabricating thin films on the curve substrate via air stream. To approach high efficiency fabricating thin film thermistors in small batch sizes, the printed NiO nanoparticle thin films were sintered by using a 355 nm wavelength ultraviolet (UV) laser; this novel fabrication method reduced several steps of the conventional manufacturing process of the thermistor. Compared with furnace heat treatments of the NiO thermistor in previous studies, the UV laser sintering not only significantly improved the electrical properties but decreased the treatment time from an hour to a second. Since the resistance declined, the thermistor has been operated at an ambient temperature, which provides ready measurement. The resistance and morphology of the thin films were analyzed for evaluating the effect of the laser treatment. To identify the proper UV laser parameters, three laser parameters, including laser output energy, frequency, and scanning speed, were studied. Due to the laser-sintering parameters, namely, 2 W, 150 mm/s, 90 kHz, and a B value of 4683 K, the resistance has been reduced from 106.8 MΩ to 6.15 MΩ at 100 °C. The experiments exhibited a series of analyses for sintering states and defects of printed NiO nanoparticle thin film, which were sintered by UV laser. For NiO nanoparticles, UV laser has higher absorption energy than that of other wavelength lasers, when excess laser output was applied to the NiO thin film, cracks were observed on the surface. It was found that the crystal plane distances were not affected by recrystallization, but the cracks were based on the XRD analysis. Based on the analysis, there were obvious regional compressive stains before the appearance of cracks, and the uneven shrinking strains caused the cracks on the surface as energy irradiation increased

Finite Element Modeling of an Elderly Person’s Cornea and Rigid Gas Permeable Contact Lenses for Presbyopic Patients

Rigid gas permeable (RGP) contact lenses are a common presbyopic correction tool. However, many patients clinically need a long period of adaptation after wearing. This study adopted finite element modeling to analyze the contact stress between RGP contact lens and an elderly person’s cornea. The RGP-lens-produced stress concentration at the corneal edge and maximum pressure on the cornea of elderly subjects aged >64 years was 104.140 kPa, but only 86.889 kPa for the 15–64 group. Therefore, how to decrease the stress concentration on the cornea is important to increasing elderly user comfort while wearing lenses. This study found that when the contact angle is designed on the basis of patient’s actual radian of corneal edge, the contact stress dropped sharply to 60.966 kPa, thus increasing user’s wearing comfort

Progress and Viewpoints of Multifunctional Composite Nanomaterials for Glioblastoma Theranostics

The most common malignant tumor of the brain is glioblastoma multiforme (GBM) in adults. Many patients die shortly after diagnosis, and only 6% of patients survive more than 5 years. Moreover, the current average survival of malignant brain tumors is only about 15 months, and the recurrence rate within 2 years is almost 100%. Brain diseases are complicated to treat. The reason for this is that drugs are challenging to deliver to the brain because there is a blood–brain barrier (BBB) protection mechanism in the brain, which only allows water, oxygen, and blood sugar to enter the brain through blood vessels. Other chemicals cannot enter the brain due to their large size or are considered harmful substances. As a result, the efficacy of drugs for treating brain diseases is only about 30%, which cannot satisfy treatment expectations. Therefore, researchers have designed many types of nanoparticles and nanocomposites to fight against the most common malignant tumors in the brain, and they have been successful in animal experiments. This review will discuss the application of various nanocomposites in diagnosing and treating GBM. The topics include (1) the efficient and long-term tracking of brain images (magnetic resonance imaging, MRI, and near-infrared light (NIR)); (2) breaking through BBB for drug delivery; and (3) natural and chemical drugs equipped with nanomaterials. These multifunctional nanoparticles can overcome current difficulties and achieve progressive GBM treatment and diagnosis results