Harnessing Persistent Photocurrent in a 2D Semiconductor-Polymer Hybrid Structure: Electron Trapping and Fermi Level Modulation for Optoelectronic Memory.

Recently, 2D semiconductor-based optoelectronic memory has been explored to overcome the limitations of conventional von Neumann architectures by integrating optical sensing and data storage into one device. Persistent photocurrent (PPC), essential for optoelectronic memory, originates from charge carrier trapping according to the Shockley-Read-Hall (SRH) model in 2D semiconductors. The quasi-Fermi level position influences the activation of charge-trapping sites. However, the correlation between quasi-Fermi level modulations and PPC in 2D semiconductors has not been extensively studied. In this study, we demonstrate optoelectronic memory based on a 2D semiconductor-polymer hybrid structure and confirm that the underlying mechanism is charge trapping, as the SRH model explains. Under light illumination, electrons transfer from polyvinylpyrrolidone to p-type tungsten diselenide, resulting in high-level injection and majority carrier-type transitions. The quasi-Fermi level shifts upward with increasing temperature, improving PPC and enabling optoelectronic memory at 433 K. Our findings offer valuable insights into optimizing 2D semiconductor-based optoelectronic memory.

SCREENING PRACTICES AND LATE DIAGNOSIS OF HYDROXYCHLOROQUINE RETINOPATHY IN ASIAN PATIENTS.

PURPOSE: To investigate the associations between screening practices and late diagnosis in Asian patients with hydroxychloroquine retinopathy. METHODS: In total, 92 Korean patients with hydroxychloroquine retinopathy were included and separated into late diagnosis and earlier diagnosis groups according to the retinopathy stage at the time of diagnosis. Details of screening practices regarding timing and modalities for baseline and annual monitoring examinations were compared between the two groups. Adherence to the current American Academy of Ophthalmology guidelines was compared between the two groups. RESULTS: Timing of baseline and initial monitoring examinations was appropriate as per the Academy of Ophthalmology guidelines in only 5.3% of patients with late diagnosis. There were significant differences in the proportions of patients receiving initial monitoring at 5 years of use and those receiving annual monitoring between the late and earlier diagnosis groups ( P = 0.003 and <0.001, respectively). The duration from the start date of hydroxychloroquine therapy to the first monitoring examination was significantly prolonged in the late diagnosis group ( P < 0.001). Multivariate logistic regression revealed significant association of the time duration with the first monitoring examination ( P = 0.042) and age ( P = 0.028) with late diagnosis. CONCLUSION: Results of this study suggest that poor adherence to the Academy of Ophthalmology guideline, particularly delayed initial monitoring, may be associated with late diagnosis of hydroxychloroquine retinopathy.

Hemodialysis-induced positional changes in lamina cribrosa.

This study is aimed to investigate the effect of hemodialysis (HD) on the lamina cribrosa (LC) of the optic nerve head (ONH) using swept-source optical coherence tomography (SS-OCT) and other ophthalmological parameters in patients with end-stage kidney disease (ESKD). This prospective observational study included 29 patients who underwent HD for ESKD. ONH parameters including neural canal diameter (NCD), peripapillary vertical height (PVH), and anterior LC depth (LCD), were assessed using SS-OCT. Changes in the ONH parameters before and after HD were statistically analysed. Correlations between changes in the LCD and other ocular and systemic measurements were identified using Pearson's correlation analyses. The mean anterior LCD significantly decreased from 441.6 ± 139.8 µm before HD to 413.5 ± 141.7 µm after HD (P = 0.001). Mean NCD and PVH did not show significant changes after HD (P = 0.841 and P = 0.574, respectively). A significant correlation was found between changes in the anterior LCD and the mean ocular perfusion pressure (r = 0.397, P = 0.036). We observed a significant decrease in anterior LCD after HD. Our study suggests that HD can influence the ONH, especially in the LC.

Highly conductive, conformable ionic laser-induced graphene electrodes for flexible iontronic devices.

Iontronic devices, recognized for user-friendly soft electronics, establish an electrical double layer (EDL) at the interface between ion gels and electrodes, significantly influencing device performance. Despite extensive research on ion gels and diverse electrode materials, achieving a stable interfacial formation remains a persistent challenge. In this work, we report a solution to address this challenge by employing CO2 irradiation as a bottom-up methodology to directly fabricate highly conductive, conformable laser-induced graphene (LIG) electrodes on a polyimide (PI)-based ion gel. The PI ion gel exhibits exceptional EDL formation at the electrode interface, primarily attributable to efficient ion migration. Particularly, ionic laser-induced graphene (i-LIG) electrodes, derived from the PI ion gel as a precursor, yield high-quality graphene with enhanced crystallinity and an expanded porous structure in the upward direction. This outcome is achieved through a pronounced thermal transfer effect and intercalation phenomenon between graphene layers, facilitated by the presence of ionic liquids (ILs) within the PI ion gel. Ultimately, in comparison to alternative soft electrode-based vertical capacitors, the utilization of i-LIGs and PI ion gels in the vertical capacitor demonstrates reduced interfacial resistance and increased EDL capacitance, emphasizing the extensive potential of iontronic devices. These results not only highlight these features but also introduce a new perspective for advancing next-generation iontronic devices.

Diagnostic performance of wide-field optical coherence tomography angiography for high myopic glaucoma.

Diagnosing and monitoring glaucoma in high myopic (HM) eyes are becoming very important; however, it is challenging to diagnose this condition. This study aimed to evaluate the diagnostic ability of wide-field optical coherence tomography angiography (WF-OCTA) maps for the detection of glaucomatous damage in eyes with HM and to compare the diagnostic ability of WF-OCTA maps with that of conventional imaging approaches, including swept-source optical coherence tomography (SS-OCT) wide-field maps. In this retrospective observational study, a total 62 HM-healthy eyes and 140 HM eyes with open-angle glaucoma were included. Patients underwent a comprehensive ocular examination, including SS-OCT wide-field and 12 × 12 WF-OCTA scans. The WF-OCTA map represents the peripapillary and macular superficial vascular density maps. Glaucoma specialists determined the presence of glaucomatous damage in HM eyes by reading the WF-OCTA map and comparing its sensitivity and specificity with those of conventional SS-OCT images. The sensitivity and specificity of 12 × 12 WF-OCTA scans for HM-glaucoma diagnosis were 87.28% and 86.94%, respectively, while, the sensitivity and specificity of SS-OCT wide-field maps for HM-glaucoma diagnosis were 87.49% and 80.51%, respectively. The specificity of the WF-OCTA map was significantly higher than that of the SS-OCT wide-field map (p < 0.05). The sensitivity of the WF-OCTA map was comparable with that of the SS-OCT wide-field map (p = 0.078). The WF-OCTA map showed good diagnostic ability for discriminating HM-glaucomatous eyes from HM-healthy eyes. As a complementary method to an alternative imaging modality, WF-OCTA mapping can be a useful tool for the detection of HM glaucoma.

Nanozyme-assisted molecularly imprinted polymer-based indirect competitive ELISA for the detection of marine biotoxin.

Saxitoxin (STX), which is produced by certain dinoflagellate species, is a type of paralytic shellfish poisoning toxin that poses a serious threat to human health and the environment. Therefore, developing a technology for the convenient and cost-effective detection of STX is imperative. In this study, we developed an affinity peptide-imprinted polymer-based indirect competitive ELISA (ic-ELISA) without using enzyme-toxin conjugates. AuNP/Co3O4@Mg/Al cLDH was synthesized by calcining AuNP/ZIF-67@Mg/Al LDH, which was obtained by combining AuNPs, ZIF-67, and flower-like Mg/Al LDH. This synthesized nanozyme exhibited high catalytic activity (Km = 0.24 mM for TMB and 132.5 mM for H2O2). The affinity peptide-imprinted polymer (MIP) was imprinted with an STX-specific template peptide (STX MIP) on a multi-well microplate and then reacted with an STX-specific signal peptide (STX SP). The interaction between the STX SP and MIP was detected using a streptavidin-coated nanozyme (SA-AuNP/Co3O4@Mg/Al cLDH). The developed MIP-based ic-ELISA exhibited excellent selectivity and sensitivity, with a limit of detection of 3.17 ng/mL (equivalent: 0.317 µg/g). Furthermore, the system was validated using a commercial ELISA kit and mussel tissue samples, and it demonstrated a high STX recovery with a low coefficient of variation. These results imply that the developed ic-ELISA can be used to detect STX in real samples.

Color-encoded multicompartmental hydrogel microspheres for multiplexed bioassays.

We develop color-encoded multicompartmental hydrogel (MH) microspheres tailored for multiplexed bioassays using a drop-based microfluidic approach. Our method involves the creation of triple emulsion drops that feature thin sacrificial oil layers separating two prepolymer phases. This configuration leads to the formation of poly(ethylene glycol) (PEG) multi-compartmental core-shell microspheres through photopolymerization, followed by the removal of the thin oil layers. The core compartments stably incorporate pigments, ensuring their retention within the hydrogel network without leakage, which facilitates reliable color encoding across varying spatial positions. Additionally, we introduce small molecule fluorescent labeling into the chemically functionalized shell compartments, achieving consistent distribution of functional components without the core's contamination. Importantly, our integrated one-pot conjugation of these color-encoded microspheres with affinity peptides enables the highly sensitive and selective detection of influenza virus antigens using a fluorescence bioassay, resulting in an especially low detection limit of 0.18 nM and 0.66 nM for influenza virus H1N1 and H5N1 antigens, respectively. This approach not only highlights the potential of our microspheres in clinical diagnostics but also paves the way for their application in a wide range of multiplexed assays.

Biocompatible Electronic Skins for Cardiovascular Health Monitoring.

Cardiovascular diseases represent a significant threat to the overall well-being of the global population. Continuous monitoring of vital signs related to cardiovascular health is essential for improving daily health management. Currently, there has been remarkable proliferation of technology focused on collecting data related to cardiovascular diseases through daily electronic skin monitoring. However, concerns have arisen regarding potential skin irritation and inflammation due to the necessity for prolonged wear of wearable devices. To ensure comfortable and uninterrupted cardiovascular health monitoring, the concept of biocompatible electronic skin has gained substantial attention. In this review, biocompatible electronic skins for cardiovascular health monitoring are comprehensively summarized and discussed. The recent achievements of biocompatible electronic skin in cardiovascular health monitoring are introduced. Their working principles, fabrication processes, and performances in sensing technologies, materials, and integration systems are highlighted, and comparisons are made with other electronic skins used for cardiovascular monitoring. In addition, the significance of integrating sensing systems and the updating wireless communication for the development of the smart medical field is explored. Finally, the opportunities and challenges for wearable electronic skin are also examined.

The role of interleukin 6 in the pathogenesis of hyponatremia associated with Guillain-Barré syndrome

No disponible