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Passive radiative cooling functions by reflecting the solar spectrum and emitting infrared waves in broadband or selectively. However, cooling enclosed spaces that trap heat by greenhouse effect remains a challenge. We present a Janus emitter (JET) consisting of an Ag–polydimethylsiloxane layer on micropatterned quartz substrate. The induced spoof surface plasmon polariton helps overcome inherent emissivity loss of the polymer and creates near-ideal selective and broadband emission on the separate sides. This design results in not only remarkable surface cooling when the JET is attached with either side facing outwards but also space cooling when used as an enclosure wall. Thus, the JET can passively mitigate the greenhouse effect in enclosures while offering surface cooling performance comparable to conventional radiative coolers.

achieve this efficiency due to its dependency on the operating temperature. It is stated that the high efficiency in various SCs can be achieved at an illumination of AM 1.5G and a temperature of 25 °C. However, the temperature of the SC typically exceeds this value in outdoor conditions, where it heats up by tens of degrees above the ambient temperature, which decreases the lifespan and efficiency of the SC. [14,15] The passive radiative cooling method can potentially resolve the heating issue of the SC owing to its compact and costeffective approach. It involves spontaneously cooling objects by emitting heat to the outer space without consuming energy through the transparent atmospheric transmittance window (λ ≈ 8-13 µm). [16][17][18] Recent studies have presented various types of radiative coolers (RCs) [19][20][21][22][23][24][25][26][27] which have been demonstrated to successfully lower the temperature of SCs. [28][29][30] Research has also been conducted to theoretically analyze the effectiveness of RCs in compensating for the reduced conversion efficiency of SCs due to elevated temperatures. [31][32][33][34] However, these studies have evaluated or tested the potential of an RC on specific target SCs, such as silicon, [35][36][37][38][39] concentrated perovskite, [40][41][42][43] or low-bandgap concentrated perovskite, [41] which are limited to single-junction SCs. Further research is required to determine the type of SC that can most retain its original efficiency even at high environmental temperatures, when adapting the RC technique.The efficiency of SCs can be significantly improved through a comprehensive understanding of the practical operation of the RC on diverse SCs since the SC industry encompasses various types of cells. This study theoretically proves that the multi-junction SC (MJSC) is the most effective type of SC when an RC is applied. It also presents the limitations of the radiative cooling technique when sub-bandgap (sub-BG) absorption is considered. Consequently, the proposed MJSC is demonstrated to be immune to heating by sub-BG photons, which can lead to the development of novel SCs by reducing the burden of designing additional sub-BG filters [44] or reflectors. [45][46][47] A structure is then fabricated which performs both light trapping and radiative cooling based on pioneering SC research, and is applied to the InGaP/GaAs/Ge MJSC. Multiple outdoor experiments are conducted to demonstrate that radiative cooling can contribute to a temperature drop of ≈6 °C. The reduced temperature also results in an absolute increase of the open-circuitThe power-conversion efficiency of solar cells (SCs) is reduced at high temperatures. A radiative cooling process can be implemented to overcome this issue. The radiative cooler (RC) presents considerable potential in the design of an ideal broadband emitter, which emits heat through the entire atmospheric transmittance window for devices with operating temperatures that significantly exceed the ambient temperature. However, the performance of thes...

To reduce the network traffic and service delay in next-generation networks, popular contents (videos and music) are proposed to be temporarily stored in the cache located at the edge nodes such as base stations. The challenging issue in the caching process is to correctly predict the popular contents to store, since the more popular the contents, the more reduction in the network traffic and the service delay occurs. Furthermore, network virtualization proposes an existing cellular network to decouple into infrastructure providers (InPs) and mobile virtual network operators (MVNOs) to reduce capital and operation costs. In this architecture, MVNOs lease the physical resources (network capacity and cache storage) from InPs, the owner of the resources, to provide services to their users. On the one hand, if an MVNO leases more resources than necessary, they will be wasted. On the other hand, if an MVNO leases fewer resources than necessary, the traffic and service delay will increase. Our objective is to lease enough resources without going under or over the required amount and store the most popular contents. Thus, we propose a deep learning-based prediction scheme to intelligently manage the resource leasing and caching process to improve MVNO's profit. The main challenging issue in utilizing the deep-learning is searching for the problem specific bestsuited prediction model. Hence, we also propose a reinforcement learning-based model searching scheme to find the best suited deep-learning model. We implement the prediction models using the Keras and Tensorflow libraries and the performance of the cache leasing and caching schemes are tested with a Pythonbased simulator. In terms of utility, simulation results present that the proposed scheme outperforms 46% compared with the randomized caching with optimal cache leasing scheme. INDEX TERMSMulti-access edge computing, wireless network virtualization, cache space leasing, proactive caching, reinforcement learning-based deep learning model searching. KYI THAR received the bachelor's degree in computer technology from the University of Computer Studies, Yangon, Myanmar, in 2007. He is currently pursuing the Ph.D. degree with the Department of Computer Science and Engineering, Kyung Hee University, South Korea, for which he received a scholarship for his graduate study, in 2012. His research interest includes name-based routing, in-network caching, multimedia communication, scalable video streaming, wireless network virtualization, deep learning, and the future Internet.

A glucose biosensor was utilized as a platform for the time-temperature integrator (TTI), a device for intelligent food packaging. The TTI system is composed of glucose oxidase, glucose, a pH indicator, and a three-electrode potentiostat, which produces an electrical signal as well as color development. The reaction kinetics of these response variables were analyzed under isothermal conditions. The reaction rates of the electrical current and color changes were 0.0360 ± 0.0020 (95% confidence limit), 0.0566 ± 0.0026, 0.0716 ± 0.0024, 0.1073 ± 0.0028 µA/min, and 0.0187 ± 0.0005, 0.0293 ± 0.0018, 0.0363 ± 0.0012, 0.0540 ± 0.0019 1/min, at 5, 15, 25, and 35 °C, respectively. The Arrhenius activation energy of the current reaction (Eacurrent) was 25.0 ± 1.6 kJ/mol and the Eacolor of the color reactions was 24.2 ± 0.6 kJ/mol. The similarity of these Ea shows agreement in the prediction of food qualities between the electrical signal and color development. Consequently, the function of the new time-temperature integrator system could be extended to that of a biosensor compatible with any electrical utilization equipment.

Regulation of tyrosine phosphorylation on insulin receptor substrate-1 (IRS-1) is essential for insulin signaling. The protein tyrosine phosphatase (PTP) C1-Ten/Tensin2 has been implicated in the regulation of IRS-1, but the molecular basis of this dephosphorylation is not fully understood. Here, we demonstrate that the cellular phosphatase activity of C1-Ten/Tensin2 on IRS-1 is mediated by the binding of the C1-Ten/Tensin2 Src-homology 2 (SH2) domain to phosphatidylinositol-3,4,5-trisphosphate (PtdIns(3,4,5)P). We show that the role of C1-Ten/Tensin2 is dependent on insulin-induced phosphoinositide 3-kinase activity. The C1-Ten/Tensin2 SH2 domain showed strong preference and high affinity for PtdIns(3,4,5)P. Using site-directed mutagenesis, we identified three basic residues in the C1-Ten/Tensin2 SH2 domain that were critical for PtdIns(3,4,5)P binding but were not involved in phosphotyrosine binding and PTP activity. Using a PtdIns(3,4,5)P binding-deficient mutant, we showed that the specific binding of the C1-Ten/Tensin2 SH2 domain to PtdIns(3,4,5)P allowed C1-Ten/Tensin2 to function as a PTP in cells. Collectively, our findings suggest that the interaction between the C1-Ten/Tensin2 SH2 domain and PtdIns(3,4,5)P produces a negative feedback loop of insulin signaling through IRS-1.

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