Self‐assembled monolayers (SAMs) offer the advantage of facile interfacial modification, leading to significant improvements in device performance. In this study, we report the design and synthesis ...of a new series of carboxylic acid‐functionalized porphyrin derivatives, namely AC‐1, AC‐3, and AC‐5, and present, for the first time, a strategy to exploit the large π‐moiety of porphyrins as a backbone for interfacing the indium tin oxide (ITO) electrode and perovskite active layer in an inverted perovskite solar cell (PSC) configuration. The electron‐rich nature of porphyrins facilitates hole transfer and the formation of SAMs, resulting in a dense surface that minimizes defects. Comprehensive spectroscopic and dynamic studies demonstrate that the double‐anchored AC‐3 and AC‐5 enhance SAMs on ITO, passivate the perovskite layer, and function as conduits to facilitate hole transfer, thus significantly boosting the performance of PSCs. The champion inverted PSC employing AC‐5 SAM achieves an impressive solar efficiency of 23.19 % with a high fill factor of 84.05 %. This work presents a novel molecular engineering strategy for functionalizing SAMs to tune the energy levels, molecular dipoles, packing orientations to achieve stable and efficient solar performance. Importantly, our comprehensive investigation has unraveled the associated mechanisms, offering valuable insights for future advancements in PSCs.
We have developed a series of new self‐assembled monolayers (SAMs) based on ZnII porphyrin for use as hole‐selective layer (HSL) in inverted perovskite solar cells (PSCs). Our study successfully demonstrates the superior performance of dual carboxylic acid functionalized porphyrins can boost the solar efficiency of PSCs. The outstanding performance of these porphyrin SAMs lies in their inherent self‐assembled properties and the presence of dual carboxylic acid groups that facilitate effective anchoring to both the ITO surface and perovskites.
The hypoxia region in a solid tumor has been recognized as a complex microenvironment revealing very low oxygen concentration and deficient nutrients. The hypoxic environment reduces the ...susceptibility of the cancer cells to anticancer drugs, low response of free radicals, and less proliferation of cancer cells in the center of the solid tumors. However, the reduced oxygen surroundings provide an appreciable habitat for anaerobic bacteria to colonize. Here, we present the bacteria-mediated targeting hypoxia to offer the expandable spectra for diagnosis and therapy in cancer diseases. Two delivery approaches involving a cargo-carrying method and an antibody-directed method were designed to deliver upconversion nanorods for imaging and Au nanorods for photothermal ablation upon near-infrared light excitation for two forms of the anaerobic Bifidobacterium breve and Clostridium difficile. The antibody-directed strategy shows the most effective treatment giving stronger imaging and longer retention period and effective therapy to completely remove tumors.
Glucocorticoids serve important regulatory functions for many physiological processes and are critical mediators of the stress response. The stress response is a set of bodily processes aimed at ...counteracting a state of threatened homeostasis. Proper stress response is critical for the survival of an animal, however prolonged or abnormal stress response can be detrimental and is implicated in a number of human diseases such as depression and metabolic diseases. To dissect the underlying mechanism of this complex and important response, the zebrafish, Danio rerio offer important advantages such as ease of genetic manipulations and high-throughput behavioral analyses. However, there is a paucity of suitable methods to measure stress level in larval zebrafish. Therefore, an efficient low-cost method to monitor stress hormone levels will greatly facilitate stress research in zebrafish larvae. In this study, we optimized sample collection as well as cortisol extraction methods and developed a home-made ELISA protocol for measuring whole-body cortisol level in zebrafish larvae. Further, using our customized protocols, we characterized the response of larval zebrafish to a variety of stressors. This assay, developed for efficient cortisol quantification, will be useful for systematic and large-scale stress analyses in larval zebrafish.
According to California's 2016 Building Energy Efficiency Standards, the percentage flicker of light-emitting diode (LED) lighting fixtures should be below 30 %. However, the percentage flicker of ...commercially available linear power supplies is generally between 25 % and 99.9 %; thus, some LED lighting fixtures that use linear power supplies have been unable to enter the European or American markets. The traditional method of effectively reducing flicker involves increasing the capacitance of the electrolytic capacitor of the power supply, which causes an increase in the height of the lamp board components as well as shadowing and dark band phenomena. This paper presents a power supply circuit that uses only electrolytic capacitors with low capacitance and exhibits constant power, constant light output, and a lamp board thickness of only 8 mm; it can achieve a percentage flicker of less than 10 %, which exceeds international standards. Power efficiency is a crucial performance indicator of linear power supplies. Because linear power supplies are mostly integrated circuits (ICs) with extremely small package volumes, higher power efficiency results in lower heat loss. The international standard for the power efficiency of linear power supplies is approximately 75 %. A multistage switching mechanism is used in the proposed power supply to achieve an overall efficiency of > 88 %. Under an input power of 12 W, a 10 % increase in efficiency reduces the heat by 1.2 W, which can considerably reduce the difficulty and cost of heat dissipation in IC packages. By combining the aforementioned technologies, the proposed power supply can achieve high efficiency and low percentage flicker, thereby improving the shortcomings of traditional linear power supplies. Currently, the driver-on-board (DOB) module of the proposed power supply is in the trial production phase, and its market entry will be accelerated to expand the market share of linear power supplies.
Graphite oxide (GO) synthesized from the oxidation of graphite powders exhibits p-type conductivity and is active in photocatalytic H2 evolution from water decomposition. The p-type conductivity ...hinders hole transfer for water oxidation and suppresses O2 evolution. Treating GO with NH3 gas at room temperature tunes the electronic structure by introducing amino and amide groups to its surface. The ammonia-modified GO (NGO) exhibits n-type conductivity in photoelectrochemical analysis and has a narrower optical band gap than GO. Electrochemical analysis attributes the band gap reduction to a negative shift of the valence band. An NGO-film electrode exhibits a substantially higher incident photo-to-current efficiency in the visible light region than a GO electrode. Photoluminescence analyses demonstrate the above-edge emission characteristic of GO and NGO. NH3 treatment enhances the emission by removing nonirradiative epoxy and carboxyl sites on the GO. In half-reaction tests of water decomposition, NGO effectively catalyzes O2 evolution in an aqueous AgNO3 solution under mercury-lamp irradiation, whereas GO is inactive. NGO also effectively catalyzes H2 evolution in an aqueous methanol solution but shows less activity than GO. Under illumination with visible light (λ > 420 nm), NGO simultaneously catalyzes H2 and O2 evolutions, but with a H2/O2 molar ratio below 2. The n-type conductivity of NGO may hinder electron transfer and form peroxide species instead of H2 molecules. This study demonstrates that the functionality engineering of GO is a promising technique to synthesize an industrially scalable photocatalyst for overall water splitting.
Chromium‐doped zinc gallate, ZnGa2O4:Cr3+ (ZGC), is viewed as a long‐lasting luminescence (LLL) phosphor that can avoid tissue autofluorescence interference for in vivo imaging detection. ZGC is a ...cubic spinel structure, a typical agglomerative or clustered morphology lacking a defined cubic shape, but a sphere‐like feature is commonly obtained for the nanometric ZGC. The substantial challenge remains achieving a well‐defined cubic feature in nanoscale. The process by which dispersed and well‐defined concave cubic ZGC is obtained is described, exhibiting much stronger LLL in UV and X‐ray excitation for the dispersed cubic ZGC compared with the agglomerative form that cannot be excited using X‐rays with a low dose of 0.5 Gy. The cubic ZGC reveals a specific accumulation in liver and 0.5 Gy used at the end of X‐ray excitation is sufficient for imaging of deep‐seated hepatic tumors. The ZGC nanocubes show highly passive targeting of orthotopic hepatic tumors.
Dispersed and well‐defined ZnGa2O4:Cr3+ (ZGC) concave nanocubes are reported as providing highly passive targeting of deep‐seated hepatic tumors. They also exhibit much stronger long‐lasting luminescence in UV and X‐ray excitation for the dispersed cubic ZGC compared with the agglomerative form that cannot be charged using X‐rays with a low dose of 0.5 Gy.
In this report, a pivotal improvement in the performance of dye‐sensitized solar cells has been achieved, thus taking it one step closer toward the commercialization. Through the stepwise ...modification on the anthracene‐based organic sensitizers, the alteration of alkyl to alkoxy chain and incorporation of electron deficient moieties in the new sensitizing dyes TY3, TY4, and TY6 are found to play a significant role in the efficiency enhancement. The dye TY6, when tested under 1 sun (AM 1.5G) illumination, is found to exhibit the best efficiency of 8.08% in the series reported here. Taking it further, sensitizer TY6 achieves a milestone by displaying an efficiency of 28.56% when tested under T5 fluorescent illumination of 6000 lux and 20.72% under same illuminance from a commercial light emitting diode light source. Such an excellent performance can be attributed to its outstanding J
SC and V
OC, which are characteristic properties of these anthracene dyes.
New anthracene‐based sensitizers are designed for the application in dye‐sensitized solar cells. Alteration of alkyl to alkoxy chain and incorporation of electron deficient moieties in these dyes (TY3, TY4, and TY6) are found to play a significant role in the efficiency enhancement. The dye TY6 showed best efficiency of 8.08% and 28.56% under 1 sun and T5 illumination, respectively.
Gaussian process regression (GPR) is frequently used for uncertain measurement and prediction of nonstationary time series in the Internet of Things data, nevertheless, the generalization and ...regression efficacy of GPR are directly impacted by its selection of hyper-parameters. In the study, a non-inertial particle swarm optimization with elite mutation-Gaussian process regression (NIPSO-GPR) is proposed to optimize the hyper-parameters of GRP. NIPSO-GPR can adaptively obtain hyper-parameters of GPR via uniform non-inertial velocity update formula and adaptive elite mutation strategy. When compared with several frequently used algorithms of hyper-parameters optimization on linear and nonlinear time series sample data, experimental results indicate that GPR after hyper-parameters optimized by NIPSO-GPR has better fitting precision and generalization ability.
Environmental education has long been closely related to sustainable development. In this study, in response to the United Nations Sustainable Development Goals (SDGs), an augmented reality (AR) ...digital picture book was created using the unique natural ecosystem of Taiwan's Orchid Island as a source of self-efficacy for science learning.
Interactive environmental education learning through AR drawing was used to determine whether students' science learning self-efficacy and environmental attitudes significantly influenced the environmental behavioral skills of culturally diverse children. In this study, 26 elementary sixth-grade Taiwanese students and 26 elementary sixth-grade Japanese students were invited to participate in an extended reality drawing activity as an environmental education curriculum.
Based on the sample size of 52, the survey results were accurate with a sampling error of 3.8% with a confidence level of 95%. A questionnaire survey was administered to the 52 students after the event. After the valid questionnaire samples were collected, a partial least squares structural equation modeling (PLS-SEM) analysis was conducted with Smart PLS 3.0 on the small sample. The results of the study showed that students who had a better self-efficacy in science learning were more likely to engage in conservation actions related to the natural environment in their daily lives.
In this study, the constructs of environmental behavior were further discussed and the hypothesis model was validated using the quantitative empirical method. The results of the study revealed good reliability, convergent validity, and discriminant validity of the constructs in the hypothesis model, and the hypothesis model itself was validated. In the validated model, students' science learning self-efficacy affects the sustainability of their environmental behaviors, but only through the role of environmental attitudes. However, the environmental attitudes construct plays a fully mediating role in the model.
Regulatory T cells (Tregs) adopt specialized phenotypes defined by coexpression of lineage-defining transcription factors, such as RORγt, Bcl-6, or PPARγ, alongside Foxp3. These Treg subsets have ...unique tissue distributions and diverse roles in maintaining organismal homeostasis. However, despite extensive functional characterization, the factors driving Treg specialization are largely unknown. In this article, we show that c-Maf is a critical transcription factor regulating this process in mice, essential for generation of both RORγt
Tregs and T follicular regulatory cells, but not for adipose-resident Tregs. c-Maf appears to function primarily in Treg specialization, because IL-10 production, expression of other effector molecules, and general immune homeostasis are not c-Maf dependent. As in other T cells, c-Maf is induced in Tregs by IL-6 and TGF-β, suggesting that a combination of inflammatory and tolerogenic signals promote c-Maf expression. Therefore, c-Maf is a novel regulator of Treg specialization, which may integrate disparate signals to facilitate environmental adaptation.
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