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Encapsulating materials for light‐emitting diodes (LEDs) with optical‐grade polymeric resin is essential to protect from external environments and to improve light‐extraction efficiency (LEE) in micro‐scale LED (µ‐LED). In addition, the formation of microlens can further enhance the optical performance of µ‐LED. However, previously developed materials have limitations due to a lack of rheological properties and thermal stability. Here, the fabrication of sol–gel derived phenyl siloxane hybrid (PSH) that has a high refractive index (n), for use as an encapsulating material for µ‐LEDs is reported. Fumed silica nanoparticles (FSNs) are mixed with the PSH to yield siloxane/silica nanocomposites that have thixotropic properties, which enable the formation of microlens arrays. Optimizing the concentration of FSN in the nanocomposites yields a siloxane/silica nanocomposite that has a high n = 1.590 at 486 nm, high thixotropic index = 3.956, and increased optical haze (79.83% at 550 nm) makes light scattering. The use of PSH significantly increases the LEE of the LED (124.6% increase compared to an LED that does not use it). Finally, the siloxane/silica nanocomposite is used to direct‐dispense microlenses on µ‐LEDs in arrays. The encapsulation strategy can increase both the LEE and reliability of µ‐LEDs. [ABSTRACT FROM AUTHOR]

This study conducted a rapid review to evaluate active air sampling and analytical methods for characterizing outdoor air microplastics in urban areas. We synthesized information from 35 peer-reviewed journal articles. Studies utilizing active sampling methods were able to provide detailed data on inhalation concentrations and doses. The analytical techniques reviewed were categorized into microscopy, Fourier Transform Infrared (FTIR) spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), and mass spectrometry, including pyrolysis–gas chromatography (Py-GC). While conventional FTIR and Raman spectroscopy can identify microplastics in total suspended particles, advanced instruments such as µRaman and SEM are crucial for analyzing inhalable microplastics (e.g., particles smaller than 10 µm). Characterizing the shapes and colours of microplastics can provide qualitative estimates of their sources, with fibres and the colour black being the most predominant characteristics. Establishing dose–response relationships for health effects requires quantitative analyses; thus, combining techniques like µRaman with Py-GC is essential for comprehensive human risk assessments. Future studies should focus on identifying and quantifying inhalable microplastic compounds that are relevant to human health. [ABSTRACT FROM AUTHOR]

In this study, we introduce the world's first development of a full‐color micro‐LED display utilizing a Simultaneous Transfer and Bonding (SITRAB) process and a novel SITRAB film. Developed micro‐LED display involves R/G/B micro‐LED chips measuring 35 × 20 µm 2, arranged into a display resolution of 32 × 32, with a pixel pitch of 324 µm and a subpixel pitch of 50 µm. The micro‐LED display utilizes a glass substrate and aluminum wiring. A key innovation in our process is the use of indium solder for low‐temperature bonding, significantly enhancing the assembly process's efficiency and reliability. The SITRAB film, a specially developed material by ourselves, removes the surface oxide of indium solders, facilitating effective bonding between the micro‐LEDs and the display electrodes. Post‐curing of this SITRAB film further enhances the shear strength of the micro‐LEDs. An average shear strength of approximately 5.45 gf (about 32 MPa), significantly surpassing the tensile strength of indium. These advancements not only demonstrate the feasibility of the SITRAB process and the new film material in creating high‐quality micro‐LED displays but also significantly boost the reliability of these displays. [ABSTRACT FROM AUTHOR]

Micro light‐emitting diodes (µLEDs) have been considered as next‐generation display technologies, but they suffer from low productivity due to poor heat dissipation, high electrical resistance, and repair difficulty of conventional µLED bonding methods. Simultaneous transfer and bonding (SITRAB) technology enables electrically/thermally conductive soldering for high‐resolution µLED displays. In this study, the transfer, bonding, and repair of InGaN/GaN µLEDs via the SITRAB method are reported. µLEDs grown on sapphire substrates are assembled on a backplane via the SITRAB process. The SITRAB‐based repair of defective pixels is demonstrated by transferring redundant LEDs to the display substrates. [ABSTRACT FROM AUTHOR]

mRNA variance has been proposed to play key roles in normal development, population fitness, adaptability, and disease. While variance in gene expression levels may be beneficial for certain cellular processes, for example in a cell's ability to respond to external stimuli, variance may be detrimental for the development of some organs. In the bilaterally symmetric vertebrate limb buds, the amount of Sonic Hedgehog (SHH) protein present at specific stages of development is essential to ensure proper patterning of this structure. To our surprise, we found that SHH protein variance is present during the first 10 hr of limb development. The variance is virtually eliminated after the first 10 hr of limb development. By examining mutant animals, we determined that the ability of the limb bud apical ectodermal ridge (AER) to respond to SHH protein was required for reducing SHH variance during limb formation. One consequence of the failure to eliminate variance in SHH protein was the presence of polydactyly and an increase in digit length. These data suggest a potential novel mechanism in which alterations in SHH variance during evolution may have driven changes in limb patterning and digit length., (Copyright © 2017 Zhang et al.)