Metformin facilitates anti-PD-L1 efficacy through the regulation of intestinal microbiota.

Metformin is a synthetic biguanide proven to have beneficial effects against various human diseases. Research has confirmed that metformin exerts its effects by regulating the composition of intestinal microbiota. The composition of intestinal microbiota influences the efficacy of anti-PD-L1 immunotherapy. We assume that the regulation of metformin on intestinal microbiota could enhance the therapeutic efficiency of anti-PD-L1 antibodies. In Lewis lung cancer-bearing C57BL/6J mice, we find that metformin enhances PD-L1 antibody efficacy mainly depending on the existence of gut microbiota, and metformin increases the anti-tumor immunity through modulation of intestinal microbiota and affects the integrity of the intestinal mucosa. Antibiotic depletion of gut microbiota abolished the combination efficacy of PD-L1 antibody and metformin, implying the significance of intestinal microbiota in metformin's antitumor action. Combining anti-PD-L1 antibody with metformin provoked tumor necrosis by causing increased CD8 T-cell infiltration and IFN-γ expression. In conclusion, metformin could be employed as a microecological controller to prompt antitumor immunity and increase the efficacy of anti-PD-L1 antibodies. Our study provided reliable evidence that metformin could be synergistically used with anti-PD-L1 antibody to enhance the anti-cancer effect.

Insights on the Contradiction between the Affinity and Capacity of Ferrihydrite toward As(III) and As(V): Surface Reaction Revisited.

Ferrihydrite is omnipresent in nature, and its adsorption of As(III/V) decides the migration of arsenic. Although As(III) is commonly recognized as the more mobile species of inorganic arsenic, it sometimes exhibits less mobility in ferrihydrite systems, which calls for further insights. In this study, we elucidated the adsorption behavior and mechanisms of As(III/V) on ferrihydrite under different loading levels (molar ratio As/Fe = 0-0.38), solution pH (3-10), and coexisting ions [P(V) and Ca(II)] based on batch adsorption experiments, surface complexation modeling, density functional theory calculations, and X-ray photoelectron spectroscopy. Our results show that As(III) exhibits weaker adsorption affinity but a larger capacity compared with that of As(V). On ferrihydrite, As(III) and As(V) are adsorbed mainly as bidentate mononuclear complexes at type-a sites [≡Fe(OH-0.5)2] and bidentate binuclear complexes at type-b sites (2≡FeOH-0.5), respectively. As the dosage increases, As(III) further forms mononuclear monodentate complexes at both surface sites, resulting in a higher site utilization efficiency, while As(V) does not due to repulsive electrostatic interaction. The difference in surface species of As(III/V) also leads to complex responses when coexisting with high concentrations of P(V) and Ca(II). This study helps us to understand environmental behavior of As(III/V) and develop remediation strategy in As(III/V) contaminated systems.

Automatic Shrimp Fry Counting Method Using Multi-Scale Attention Fusion.

Shrimp fry counting is an important task for biomass estimation in aquaculture. Accurate counting of the number of shrimp fry in tanks can not only assess the production of mature shrimp but also assess the density of shrimp fry in the tanks, which is very helpful for the subsequent growth status, transportation management, and yield assessment. However, traditional manual counting methods are often inefficient and prone to counting errors; a more efficient and accurate method for shrimp fry counting is urgently needed. In this paper, we first collected and labeled the images of shrimp fry in breeding tanks according to the constructed experimental environment and generated corresponding density maps using the Gaussian kernel function. Then, we proposed a multi-scale attention fusion-based shrimp fry counting network called the SFCNet. Experiments showed that our proposed SFCNet model reached the optimal performance in terms of shrimp fry counting compared to CNN-based baseline counting models, with MAEs and RMSEs of 3.96 and 4.682, respectively. This approach was able to effectively calculate the number of shrimp fry and provided a better solution for accurately calculating the number of shrimp fry.

Iron overload facilitates neonatal hypoxic-ischemic brain damage via SLC7A11-mediated ferroptosis.

Oxidative damage and cell death are involved in the pathogenesis of hypoxic-ischemic brain damage (HIBD). Ferroptosis is a newly identified mode of cell death that results from the oxidative damage induced by excessive iron. In HIBD, iron accumulates in brain tissues due to the massive destruction of red blood cells and increased permeability of the blood brain barrier vasculature, which can trigger ferroptosis. Ferroptosis is implicated in various diseases involving neuronal injury; however, the roles of iron and ferroptosis in HIBD have not been identified. In the present study, we investigated the role of iron overload in neuronal ferroptosis both in HIBD rat models and in oxygen- and glucose-deprived (OGD) SH-SY5Y cells. We observed that iron deposition in the cerebral cortex was significantly increased in HIBD rats. Features of ferroptosis such as shrunken mitochondria, increased MDA (malondialdehyde) levels, and reduced solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) expression were observed in the cerebral cortex of HIBD rats. Administration of an iron chelator in HIBD rats upregulated SLC7A11 expression and alleviated neuronal ferroptosis in cerebral cortex tissue. Additionally, overexpression of SLC7A11 in SH-SY5Y cells increased cell viability and attenuated OGD-induced ferroptosis. Our results demonstrate that iron overload induces neuronal ferroptosis by inhibiting SLC7A11 expression in HIBD. Inhibition of neuronal ferroptosis may be a promising strategy to alleviate brain damage in HIBD.

Enhanced Electrorheological Performance of Core-Shell-Structured Polymerized Ionic Liquid@Doubly Polymerized Ionic Liquid Microspheres Prepared via Evaporation-Assisted Dispersion Polymerization.

A polymerized ionic liquid (PIL) provides a platform for the development of a high-performance water-free polyelectrolyte-based electrorheological fluid (ERF) because of the presence of large-size hydrophobic ion pairs. However, the large-size hydrophobic ion pairs also easily result in a low glass-transition temperature of an ordinary linear PIL, and consequently, the PIL-based ERF has to be subject to a high leaking current density and a narrow working temperature range. In this paper, we prepared a kind of core-shell-structured polymerized ionic liquid@doubly polymerized ionic liquid (PIL@D-PIL) microsphere with a linear PIL as the core and a physically cross-linked D-PIL as the shell via an evaporation-assisted dispersion polymerization method. The core-shell structure of the sample was observed by scanning electron microscopy and transmission electron microscopy. The thermal properties of the sample were tested by differential scanning calorimetery and thermogravimetric analysis. The ER effect and dielectric polarization of PIL@D-PIL microspheres when dispersed in an insulating nonpolar liquid were studied by a rheometer and dielectric spectroscopy. It shows that the glass-transition temperature and thermal stability of a PIL increased after coating with the D-PIL shell. Under electric fields, the ERF of the PIL@D-PIL microspheres exhibits a significantly reduced leaking current density and an enhanced operating temperature range compared to the ERF of single-PIL microspheres. The PIL@D-PIL microspheres can still maintain good ER effect even if the temperature is higher than the glass-transition point of the PIL core due to the protection of the D-PIL shell.

Enhanced second harmonic generation from a quasi-periodic silver dendritic metasurface.

The preparation of the vast majority of nonlinear optical metal metasurfaces currently relies on complex top-down methods such as electron beam or ion beam etching, which are expensive and difficult to meet the requirement of large area preparation. In this paper, an easily prepared quasi-periodic silver dendritic metasurface model with highQfactor is established in the near-infrared band based on a simple and easy-to-operate electrochemical deposition method. The simulations prove that the silver dendritic metasurface has a highQfactor (exceeds 104) because of its strong electric field localization ability, which is analogous to the superposition of multiple split-ring resonators. It is demonstrated that the second harmonic generation (SHG) intensity of the dendritic metasurface at a large incident angle (such as 85°) is about 30 times that of the metasurface at a small incident angle when thex-polarized pump light is incident obliquely to break the centrosymmetry of the metasurface. The influences of the incident angle or dendritic structure's dimensions on theQfactor and SHG efficiency have also been researched through a lot of simulation. This easily prepared quasi-periodic silver dendritic metasurface SHG device may provide a new avenue for the development and application of miniature, integratable nonlinear optical devices.

Cognitive Exercise for Persons with Alzheimer's Disease and Related Dementia Using a Social Robot.

Reminiscence therapy (RT) can improve the mood and communication of persons living with Alzheimer's Disease and Alzheimer's Disease related dementias (PLWD). Traditional RT requires professionals' facilitation, limiting its accessibility to PLWD. Social robotics has the potential to facilitate RT, enabling accessible, home-based RT. However, studies are needed to investigate how PLWD would perceive a robot-mediated RT (RMRT) and how to develop RMRT for positive user experience and successful adoption. In this paper, we developed a prototype of RMRT using a humanoid social robot and tested it with 12 participants (7 PLWD, 2 with mild cognitive impairment, and 3 informal caregivers). The robot automatically displayed a memory trigger on its tablet and engaged participants in a relatable conversation during RMRT. A mixed-method approach was employed to assess its acceptability and usability. Our results showed that PLWD had an overall positive user experience with the RMRT. Participants laughed and sang along with the robot during RMRT and demonstrated intention to use it. We additionally discussed robot control method and several critical problems for RMRT. The RMRT can facilitate both verbal and nonverbal social interaction for PLWD and holds promise for engaging, personalized, and efficient home-based cognitive exercises for PLWD.

IncRNA PLAC2 Upregulates CDK6 by Directly Targeting miR-29C to Promote Cell Proliferation in Lung Squamous Cell Carcinoma.

Long noncoding RN (IncRNA) placenta-specific 2 (PLAC2) plays a critical role in many cancer types. A previous study found that PLAC2 expression dysregulated in non-small cell lung cancer (NSCLC). However, its function in LSCC is not entirely known. The present study enrolled 68 lung squamous cell carcinoma (LSCC, a major subtype of NSCLC) patients (gender: 39 males and 29 females; age: 36 to 67 years old; mean age: 53.2 ± 5.5 years old). The expression levels of PLAC2 in two types of tissue (non-tumor and LSCC) were measured by quantitative PCR. LSCC cells H1581 and H1993 were transfected with PLAC2 and cyclin-dependent kinase 6 (CDK6) expression vectors and small interfering RNAs (siRNAs), as well as microRNA-29C (miR-29C) mimic and inhibitor to perform overexpression and knock-down experiment, respectively. PLAC2 was upregulated in LSCC and positively correlated with CDK6 but negatively correlated with miR-29C. During a 5-year follow-up, high expression levels of PLAC2 were found to be closely associated with poor survival. PLAC2 and CDK6 were significantly upregulated in LSCC cells, while miR-29C was remarkably downregulated. miR-29C was predicted to be a potential target of PLAC2, and RNA pull-down assay confirmed their direct interaction. Overexpression of PLAC2 led to upregulation of CDK6 and downregulation of miR-29C, while knock-down of PLAC2 showed opposite effects. Overexpression of miR-29C downregulated CDK6, while knock-down of miR-29C increased the expression levels of CDK6. However, the expression of PLAC2 was not affected by overexpression or knock-down of miR-29C. Overexpression of PLAC2 and CDK6 enhanced LSCC cell proliferation and cell cycle progression, while knock-down showed opposite effects. In addition, overexpression of miR-29C inhibited cell proliferation and cell cycle progression, while its knockdown display opposite effects. Moreover, overexpression of miR-29C suppressed the role of overexpression of PLAC2 in cell proliferation and cell cycle progression. In conclusion, PLAC2 upregulates CDK6 by downregulating miR-29C to promote LSCC cell proliferation.

Liver fibrosis scores and prognosis in patients with cardiovascular diseases: A systematic review and meta-analysis.

BACKGROUND: In patients with nonalcoholic fatty liver disease, liver fibrosis was associated with a higher risk of cardiovascular events. However, the relationship between liver fibrosis scores and clinical outcomes in patients with cardiovascular disease remains unclear. METHODS: Searching from PubMed, EMBASE and Cochrane Library databases yielded cohort studies that reported adjusted effect size between liver fibrosis scores (Fibrosis-4 score [FIB-4] or NAFLD fibrosis score [NFS]) and prognosis in patients with cardiovascular disease. The effect size was computed using a random-effects model. RESULTS: This meta-analysis included twelve cohort studies involving 25,252 patients with cardiovascular disease. Participants with the highest baseline level of FIB-4 or NFS had a significantly increased risk of cardiovascular events (FIB-4, HR: 1.75, 95% CI: 1.53-2.00, I 2  = 0%; NFS, HR: 1.92, 95% CI: 1.50-2.47, I 2  = 47%). This finding was consistent with the analysis of FIB-4 or NFS as a continuous variable (per 1-unit increment FIB-4, HR: 1.15, 95% CI: 1.06-1.24, I 2  = 72%; NFS, HR: 1.15, 95% CI: 1.07-1.24, I 2  = 71%). Furthermore, participants with the highest levels of FIB-4 or NFS had a greater risk of cardiovascular mortality (FIB-4, HR: 2.07, 95% CI: 1.19-3.61, I 2  = 89%; NFS, HR: 3.72, 95% CI: 2.62-5.29, I 2  = 60%) and all-cause mortality (FIB-4, HR: 1.81, 95% CI: 1.24-2.66, I 2  = 90%; NFS, HR: 3.49, 95% CI: 2.82-4.31, I 2  = 25%). This result was also consistent as a continuous variable. CONCLUSION: Higher levels of FIB-4 and NFS are related to an increased risk of cardiovascular events, cardiovascular mortality and all-cause mortality in patients with cardiovascular disease.

Driving Ability Evaluation and Rehabilitation for People With Alzheimer's Disease and Related Dementias.

Worldwide, it is estimated that around 50 million older adults have Alzheimer's disease and related dementias (ADRD). Cognitive deficits associated with ADRD may affect a driver's perception and decision-making and potentially cause safety concerns. Despite much research, there lacks a comprehensive cognitive evaluation to determine the driving capability of a person with ADRD and it is unclear what are the most effective training and interventions that help to enhance driving performance for these individuals. The purpose of this article is to conduct a comprehensive literature survey to review and summarize studies of driving performance evaluation and intervention for people with ADRD and discuss perspectives for future studies. Although many studies have investigated the correlations between driving behaviors and cognitive performances for people with ADRD, it remains unclear how driving behaviors and cognitive performances are associated with psychophysiological measures. We discussed the need to develop regular driving evaluation and rehabilitation protocol for people with ADRD. We also highlighted the potential benefit to combine driving tests with psychophysiological measures to assist in characterizing personalized cognitive evaluation in the behavioral evaluation process.

Inorganic Reinforced Poly(ionic liquid) Microcapsules: Confined Cooling-Assisted Phase Separation Self-Assembly and Enhanced Electroresponsive Properties.

A simple preparation of inorganic reinforced poly(ionic liquid) (PIL) microcapsules by combining dispersion polymerization and confined cooling-assisted phase separation self-assembly is reported. Silane coupling agent-modified PIL microbeads are first prepared by dispersion polymerization. Then, the microbeads are dissolved in a theta solvent composed of good solvent and non-solvent to form hollow SiOx microcapsules at a relatively high temperature. Finally, the solution is cooled to induce the nucleation and growth of dissolved PIL chains on the inner and outer surface of hollow SiOx microcapsules to form inorganic reinforced microcapsules with asymmetric PIL/SiOx /PIL sandwich-like shell. The morphology of microcapsules can be controlled by adjusting PIL concentration and cooling rate. The inorganic reinforced microcapsules show enhanced suspended stability and electroresponsive characteristic when used as the dispersed phase of smart suspensions.

Prediction of Cd Accumulation in Wheat (Triticum aestivum L.) and Simulation Calculation of Lime or Zn Fertilizer Remediated Soil.

Soil Cd contamination to wheat raise wide concerns over food safety. It is essential to find the key factors affecting Cd accumulation in wheat and to establish a predictive model. The effects of pH, Zn, Ca, and DOM on the accumulation of Cd in wheat were investigated using hydroponic experiments. The results showed that Zn was the most important factor inhibiting Cd uptake in wheat. Models were developed to predict the Cd contents in wheat tissues based on the ion concentration. Meanwhile, the available Cd contents in soil were predicted using a geochemical multi-surface model (MSM) which is suitable for various soils and conditions. The combination of the hydroponic accumulation model and MSM exhibits good predictions of wheat-Cd (R2 = 0.822-0.862, RMSE = 0.317-0.533). The results of this study can quantitatively predict the accumulation of Cd in wheat and provide a reference for soil remediation and safe wheat production.

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OBJECTIVES: To investigate whether evidence-based standardized nutrition protocol can facilitate the establishment of full enteral nutrition and its effect on short-term clinical outcomes in very preterm/very low birth weight infants. METHODS: A retrospective analysis was performed on the medical data of 312 preterm infants with a gestational age of ≤32 weeks or a birth weight of <1 500 g. The standardized nutrition protocol for preterm infants was implemented in May 2020; 160 infants who were treated from May 1, 2019 to April 30, 2020 were enrolled as the control group, and 152 infants who were treated from June 1, 2020 to May 31, 2021 were enrolled as the test group. The two groups were compared in terms of the time to full enteral feeding, the time to the start of enteral feeding, duration of parenteral nutrition, the time to recovery to birth weight, the duration of central venous catheterization, and the incidence rates of common complications in preterm infants. RESULTS: Compared with the control group, the test group had significantly shorter time to full enteral feeding, time to the start of enteral feeding, duration of parenteral nutrition, and duration of central venous catheterization and a significantly lower incidence rate of catheter-related bloodstream infection (P<0.05). There were no significant differences between the two groups in the mortality rate and the incidence rate of common complications in preterm infants including grade II-III necrotizing enterocolitis (P>0.05). CONCLUSIONS: Implementation of the standardized nutrition protocol can facilitate the establishment of full enteral feeding, shorten the duration of parenteral nutrition, and reduce catheter-related bloodstream infection in very preterm/very low birth weight infants, without increasing the risk of necrotizing enterocolitis.

Spin-decoupled metasurface for broadband and pixel-saving polarization rotation and wavefront control.

In this paper, a strategy to achieve a simultaneous wavefront shaping and polarization rotation, without compromising the number of pixels and energy efficiency as well as having broadband operation range, is proposed. This strategy is based on the application of a spin-decoupled phase metasurface composed by only one set of metal-insulator-metal (MIM) umbrella-shaped chiral unit cells. Quasi-non-dispersive and spin-decoupled phase shift can be achieved simply by changing single structural parameter of the structure. By further merging the Pancharatnam-Berry (PB) geometric phase, conversion of an incident LP light beam into right- and left-handed circularly polarized reflected beams with similar amplitudes, desired phase profiles and controlled phase retardation on a nanoscale is enabled with high efficiency. Based on the proposed strategy, a polarization-insensitive hologram generator with control optical activity, and a multiple ring vortex beam generator are realized. The results obtained in this work provide a simple and pixel-saving approach to the design of integratable and multitasking devices combining polarization manipulation and wavefront shaping functions, such as vectorial holographic generators, multifocal metalenses, and multichannel vector beam generators.

Old Is (Not) Gold: Midazolam Monotherapy versus Midazolam Plus Fentanyl for Sedation during Cardiac Catheterization.

OBJECTIVE: We aimed to study the differences in perception of pain during cardiac catheterization with midazolam monotherapy compared to the current standard of midazolam plus fentanyl. BACKGROUND: Procedural sedation is important to ensure comfort and safety in patients undergoing left heart catheterization. Despite the widespread use of midazolam and fentanyl for procedural sedation, the effectiveness of this dual agent approach to sedation has never been studied in comparison to midazolam monotherapy. METHODS: A total of 129 patients undergoing sedation for outpatient elective cardiac catheterization were randomly assigned to either midazolam monotherapy (n = 69) or combination of midazolam and fentanyl (n = 60). The primary outcome was assessment of pain perception prior to discharge by patient completion of a pain questionnaire. Participants were asked if they experienced any pain during their procedure (yes/no) and, if yes, asked to rate their overall pain level using a 10-point Likert scale that ranged from 1 (minimal pain) to 10 (worst pain imaginable). RESULTS: Most patients (n = 94, 73%) reported no pain during their procedure. Patients sedated with midazolam monotherapy reported similar average pain scores compared to patients sedated with the combination of midazolam and fentanyl (1.1 vs. 1.1, p=0.95). CONCLUSIONS: Among patients undergoing elective cardiac catheterization, no significant differences in pain scores were noted between sedation with midazolam alone compared to midazolam and fentanyl. Due to fentanyl's unfavorable interaction with P2Y12 agents, increased costs, and addiction potential, it is imperative that cardiologists revisit the role of effective procedural sedation with a single agent and avoid the use of fentanyl.

Preparation of Poly(Ionic Liquid) Microbeads via Cooling-Assisted Phase Separation Method.

A simple and large-scale non-chemical preparation of uniform poly(ionic liquid) (PIL) microbeads via a cooling-assisted phase separation (CAPS) method is reported. For this method, PIL bulk is dissolved to form a saturated solution in a mixed solvent composed of good solvent and non-solvent at a relatively high temperature. Then, the uniform PIL microbeads are prepared by cooling the solution to room temperature or a lower temperature in the absence of stabilizer. The size of microbeads can be controlled by adjusting the preparation parameters, including PIL concentration, cooling rate, and agitation state. The scale of preparation can be up to 10 g, and the yield of PIL microbeads is more than 70% or 88% when the solution is cooled to room temperature or 0 °C, respectively. The formation mechanism of PIL microbeads is discussed by tracing the nucleation and growth process by the transmittance of light of the solution during cooling. The application of this CAPS method to other polymer microbeads preparation is finally discussed by choosing different good solvent and non-solvent.

Human impact on the diversity and virulence of the ubiquitous zoonotic parasite Toxoplasma gondii.

A majority of emerging infectious diseases in humans are zoonoses. Understanding factors that influence the emergence and transmission of zoonoses is pivotal for their prevention and control. Toxoplasma gondii is one of the most widespread zoonotic pathogens known today. Whereas only a few genotypes of T. gondii dominate in the Northern Hemisphere, many genotypes coexist in South America. Furthermore, T. gondii strains from South America are more likely to be virulent than those from the Northern Hemisphere. However, it is not clear what factor(s) shaped modern-day genetic diversity and virulence of T. gondii Here, our analysis suggests that the rise and expansion of farming in the past 11,000 years established the domestic cat/mouse transmission cycle for T. gondii, which has undoubtedly played a significant role in the selection of certain linages of T. gondii Our mathematical simulations showed that within the domestic transmission cycle, intermediately mouse-virulent T. gondii genotypes have an adaptive advantage and eventually become dominant due to a balance between lower host mortality and the ability to superinfect mice previously infected with a less virulent T. gondii strain. Our analysis of the global type II lineage of T. gondii suggests its Old World origin but recent expansion in North America, which is likely the consequence of global human migration and trading. These results have significant implications concerning transmission and evolution of zoonotic pathogens in the rapidly expanding anthropized environment demanded by rapid growth of the human population and intensive international trading at present and in the future.

Global vs local control of cardiac alternans in a 1D numerical model of human ventricular tissue.

Cardiac alternans is a proarrhythmic state in which the action potential duration (APD) of cardiac myocytes alternate between long and short values and often occurs under conditions of rapid pacing of cardiac tissue. In the ventricles, alternans is especially dangerous due to the life-threatening risk of developing arrhythmias, such as ventricular fibrillation. Alternans can be formed in periodically paced tissue as a result of pacing itself. Recently, it has been demonstrated that this pacing-induced alternans can be prevented by performing constant diastolic interval (DI) pacing, in which DI is independent of APD. However, constant DI pacing is difficult to implement in experimental settings since it requires the real-time measurement of APD. A more practical way was proposed based on electrocardiograms (ECGs), which give an indirect measure of the global DI relaxation period through the TR interval assessment. Previously, we demonstrated that constant TR pacing prevented alternans formation in isolated Langendorff-perfused rabbit hearts. However, the efficacy of "local" constant DI pacing vs "global" constant TR pacing in preventing alternans formation has never been investigated. Thus, the purpose of this study was to implement an ECG-based constant TR pacing in a 1D numerical model of human ventricular tissue and to compare the dynamical behavior of cardiac tissue with that resulted from a constant DI pacing. The results showed that both constant TR and constant DI pacing prevented the onset of alternans until lower basic cycle length when compared to periodic pacing. For longer cable lengths, constant TR pacing was shown to exhibit greater control on alternans than constant DI pacing.

Quasi-Periodic Dendritic Metasurface for Integral Operation in Visible Light.

A reflective metasurface model composed of silver dendritic units is designed in this study. The integral property of this metasurface, which consists of an upper layer of dendritic structures, a silica spacer, and a bottom silver substrate was demonstrated at visible wavelengths. The simulation results revealed that the metasurface can perform integral operation in the yellow and red bands; this can be easily generalized to the infrared and communication bands by scaling the transverse dimensions of this metasurface. A dendritic metasurface sample responding to red light was prepared via the bottom-up electrochemical deposition method. The integral operation property of the sample was verified experimentally. This dendritic metasurface, which can perform integral operation in visible light, can be used for big data processing technology, real-time signal processing, and beam shaping, and provides a new method for miniaturized and integrated all-optical signal processing systems.

Influence of Tethered Ions on Electric Polarization and Electrorheological Property of Polymerized Ionic Liquids.

Polymerized ionic liquids (PILs) show potential to be used as new water-free polyelectrolyte-based electrorheological (ER) material. To direct ER material design at the molecular level, unveiling structure-property relationships is essential. While a few studies compare the mobile ions in PILs there is still a limited understanding of how the structure of tethered counterions on backbone influences ER property. In this study, three PILs with same mobile anions but different tethered countercations (e.g., poly(dimethyldiallylammonium) P[DADMA]+, poly(benzylethyl) trimethylammonium P[VBTMA]+, and poly(1-ethyl-4-vinylimidazolium hexafluorophosphate) P[C2VIm]+) are prepared and the influence of tethered countercations on the ER property of PILs is investigated. It shows that among these PILs, P[DADMA]+ PILs have the strongest ER property and P[C2VIm]+ PILs have the weakest one. By combining dielectric spectra analysis with DFT calculation and activation energy measurement, it can clarify that the influence of tethered counterions on ER property is mainly associated with ion-pair interaction energy that is affecting ionic conductivity and interfacial polarization induced by ion motion. P[DADMA]+ has the smallest ion-pair interaction energy with mobile ions, which can result in the highest ionic conductivity and the fastest interfacial polarization rate for its strongest ER property.