Ammonia Electrosynthesis from Nitrate Using a Ruthenium-Copper Cocatalyst System: A Full Concentration Range Study

Electrochemical synthesis of ammonia via the nitrate reduction reaction (NO3RR) has been intensively researched as an alternative to the traditional Haber-Bosch process. Most research focuses on the low concentration range representative of the nitrate level in wastewater, leaving the high concentration range, which exists in nuclear and fertilizer wastes, unexplored. The use of a concentrated electrolyte (≥1 M) for higher rate production is hampered by poor hydrogen transfer kinetics. Herein, we demonstrate that a cocatalytic system of Ru/Cu2O catalyst enables NO3RR at 10.0 A in 1 M nitrate electrolyte in a 16 cm2 flow electrolyzer, with 100% faradaic efficiency toward ammonia. Detailed mechanistic studies by deuterium labeling and operando Fourier transform infrared (FTIR) spectroscopy allow us to probe the hydrogen transfer rate and intermediate species on Ru/Cu2O. Ab initio molecular dynamics (AIMD) simulations reveal that adsorbed hydroxide on Ru nanoparticles increases the density of the hydrogen-bonded water network near the Cu2O surface, which promotes the hydrogen transfer rate. Our work highlights the importance of engineering synergistic interactions in cocatalysts for addressing the kinetic bottleneck in electrosynthesis.

Significant Enhancement of Circular Polarization in Light Emission through Controlling Helical Pitches of Semiconductor Nanohelices

Circularly polarized light emission (CPLE) can be potentially applied to three-dimensional displays, information storage, and biometry. However, these applications are practically limited by a low purity of circular polarization, i.e., the small optical dissymmetry factor gCPLE. Herein, glancing angle deposition (GLAD) is performed to produce inorganic nanohelices (NHs) to generate CPLE with large gCPLE values. CdSe NHs emit red CPLE with gCPLE = 0.15 at a helical pitch (P) ≈ 570 nm, having a 40-fold amplification of gCPLE compared to that at P ≈ 160 nm. Ceria NHs emit ultraviolet-blue CPLE with gCPLE ≈ 0.06 at P ≈ 830 nm, with a 103-fold amplification compared to that at P ≈ 110 nm. Both the photoluminescence and scattering among the close-packed NHs complicatedly account for the large gCPLE values, as revealed by the numerical simulations. The GLAD-based NH-fabrication platform is devised to generate CPLE with engineerable color and large gCPLE = 10-2-10-1, shedding light on the commercialization of CPLE devices.

Metal-Induced Planar Chirality of Soft-Bridged Binuclear Platinum(II) Complexes: 100% Phosphorescence Quantum Yields, Chiral Self-Sorting, and Circularly Polarized Luminescence

Pt(II) complexes have attracted a great deal of interest due to their rich phosphorescent properties. However, these square-planar Pt(II) complexes are far more likely to encounter the problems of lack of metal-induced chirality and emission "aggregation-caused quenching". Herein, soft-bridged binuclear Pt(II) complexes bearing metal-induced planar chirality were synthesized and characterized. These soft bridging ligands with smaller conjugated system would help to not only improve solubility for synthesis and enantioseparation but also introduce point chirality from amino acid for highly efficient diastereoselectivity. Furthermore, the intramolecular Pt-Pt distances could be well regulated by soft bridging ligands, and consequently the phosphorescence quantum yield up to 100% could be achieved by shortening intramolecular Pt-Pt distance for first time. These complexes can be used as emitters in highly efficient solution-processed organic light-emitting diodes.

1-Adamantanamine Hydrochloride Resists Environmental Corrosion to Obtain Highly Efficient and Stable Perovskite Solar Cells

Passivating the defective surface of perovskite film is a promising strategy to improve the stability and efficiency of perovskite solar cells (PSCs). Herein, 1-adamantanamine hydrochloride (ATH) is introduced to the upper surface of the perovskite film to heal the defects of the perovskite surface. The best-performance ATH-modified device has a higher efficiency (23.45%) than the champion control device (21.53%). The defects are passivated, interfacial nonradiative recombination is suppressed, and interface stress is released by the ATH deposited on the perovskite film, leading to longer carrier lifetimes and enhancement in open-circuit voltage (V_OC) and fill factor (FF) of the PSCs. With obvious improvement, V_OC and FF of 1.159 V and 0.796 for the control device are raised to 1.178 V and 0.826 for the ATH-modified device, respectively. Finally, during an operational stability measurement of more than 1000 h, the ATH-treated PSC exhibited better moisture resistance, thermal persistence, and light stability.

Precise modulation strategies of 2D/3D perovskite heterojunctions in efficient and stable solar cells

2D/3D perovskite heterojunctions exhibit promising prospects in the improvement of efficiency and stability of perovskite solar cells (PSCs). However, many challenges remain in the development of high-quality 2D/3D heterojunctions, such as a reliable pathway to control the perovskite phase and generally poor performance in inverted (p-i-n) devices, which limit their commercialization. Fortunately, many excellent works have proposed lots of strategies to solve these challenges, which have triggered a new wave of research on 2D/3D perovskite heterojunctions in recent years. In this paper, the latest research progress and the critical factors involved in the modulating mechanisms of PSCs with 2D/3D heterojunctions have been summarized and laid out systematically. The advantages of constructing 2D/3D perovskite heterojunctions in PSCs are highlighted, and the problems and related solutions of low-dimensional perovskites as passivation layers towards high-performance PSCs are also discussed in depth. Finally, the prospects of 2D/3D perovskite heterojunctions utilized in the passivation strategies to further improve the photovoltaic performance of PSCs in the future have been presented.

Application of Natural Molecules in Efficient and Stable Perovskite Solar Cells

Perovskite solar cells (PSCs), one of the most promising photovoltaic technologies, have been widely studied due to their high power conversion efficiency (PCE), low cost, and solution processability. The architecture of PSCs determines that high PCE and stability are highly dependent on each layer and the related interface, where nonradiative recombination occurs. Conventional synthetic chemical materials as modifiers have disadvantages of being toxic and costly. Natural molecules with advantages of low cost, biocompatibility, and being eco-friendly, and have improved PCE and stability by modifying both functional layers and interface. In this review, we discuss the roles of natural molecules on PSCs devices in terms of the perovskite active layer, interface, carrier transport layers (CTLs), and substrate. Finally, the summary and outlook for the future development of natural molecule-modified PSCs are also addressed.

Nexuses Between the Chemical Design and Performance of Small Molecule Dopant-Free Hole Transporting Materials in Perovskite Solar Cells

Perovskite solar cells (PSCs) have grabbed much attention of researchers owing to their quick rise in power conversion efficiency (PCE). However, long-term stability remains a hurdle in commercialization, partly due to the inclusion of necessary hygroscopic dopants in hole transporting materials, enhancing the complexity and total cost. Generally, the efforts in designing dopant-free hole transporting materials (HTMs) are devoted toward small molecule and polymeric HTMs, where small molecule based HTMs (SM-HTMs) are dominant due to their reproducibility, facile synthesis, and low cost. Still, the state-of-art dopant-free SM-HTM has not been achieved yet, mainly because of the knowledge gap between device engineering and molecular designs. From a molecular engineering perspective, this article reviews dopant-free SM-HTMs for PSCs, outlining analyses of chemical structures with promising properties toward achieving effective, low-cost, and scalable materials for devices with higher stability. Finally, an outlook of dopant-free SM-HTMs toward commercial application and insight into the development of long-term stability PSCs devices is provided.

Gold(I) Multi-Resonance Thermally Activated Delayed Fluorescent Emitters for Highly Efficient Ultrapure-Green Organic Light-Emitting Diodes

Acceleration of singlet-triplet intersystem crossings (ISC) is instrumental in bolstering triplet exciton harvesting of multi-resonance thermally activated delayed fluorescent (MR-TADF) emitters. This work describes a simple gold(I) coordination strategy to enhance the spin-orbit coupling of green and blue BN(O)-based MR-TADF emitters, which results in a notable increase in rate constants of the spectroscopically observed ISC process to 3×10⁹  s^-1 with nearly unitary ISC quantum yields. Accordingly, the resultant thermally-stable Au^I emitters attained large values of delayed fluorescence radiative rate constant up to 1.3×10⁵ /1.7×10⁵  s^-1 in THF/PMMA film while preserving narrowband emissions (FWHM=30-37 nm) and high emission quantum yields (ca. 0.9). The vapor-deposited ultrapure-green OLEDs fabricated with these Au^I emitters delivered high luminance of up to 2.53×10⁵  cd m^-2 as well as external quantum efficiencies of up to 30.3 % with roll-offs as low as 0.8 % and long device lifetimes (LT₆₀ ) of 1210 h at 1000 cd m^-2 .

Room-Temperature Phosphorescence of Pure Axially Chiral Bicarbazoles

Ultralong room-temperature phosphorescence (RTP) is greatly important in a series of applications, but obtaining RTP from metal-free organic materials is still an enormous challenge due to the spin-forbidden nature of triplet excitons. Because of its electron-rich nature and easy derivatization, carbazole (Cz) is widely used to build organic RTP and thermally activated delayed fluorescence (TADF) materials. However, Liu et al. (Nat. Mater. 2021, 20, 175) recently demonstrated that the RTP of Cz is induced by charge traps of its isomeric impurity in commercial sources. Here, on the basis of the classical El-Sayed rule and the recently discovered intersystem crossing promotion principles (twisted structure and charge transfer), we designed and prepared highly pure (>99.9%) (R/S)-octahydro-binaphthyl-based bicarbazoles (BiCz) for high-performance RTP (Φ_P = 23%; τ_p = 1.09 s). Interestingly, BiCz exhibited photoactivated TADF and RTP in isolated and aggregated states, respectively, and thus would be an efficient tool for rejuvenating Cz-based RTP.

Synergy Effect of a π-Conjugated Ionic Compound: Dual Interfacial Energy Level Regulation and Passivation to Promote Voc and Stability of Planar Perovskite Solar Cells

Defects and energy offsets at the bulk and heterojunction interfaces of perovskite are detrimental to the efficiency and stability of perovskite solar cells (PSCs). Herein, we designed an amphiphilic π-conjugated ionic compound (QAPyBF₄ ), implementing simultaneous defects passivation and interface energy level alignments. The p-type conjugated cations passivated the surface trap states and optimized energy alignment at the perovskite/hole transport layer. The highly electronegative [BF₄ ]^- enriched at the SnO₂ interface featured desired band alignment due to the dipole moment of this interlayer. The planar n-i-p PSC had an efficiency of 23.1 % with V_oc of 1.2 V. Notably, the synergy effect elevated the intrinsic endothermic decomposition temperature of the perovskite. The modified devices showed excellent long-term thermal (85 °C) and operational stability at the maximum power point for 1000 h at 45 °C under continuous one-sun illumination with no appreciable efficiency loss.

[Effective dose and adverse reactions analysis of Remimazolam for sedation in elderly patients undergoing gastroscopy]

Objective: To explore the 50% effective dose (ED50) and 95% effective dose (ED95) of Remimazolam during gastroscopic sedation in elderly patients, and to observe the adverse reactions during anesthesia. Methods: From July to November 2020, 39 elderly patients, of which there were 18 males and 21 females, aged from 65 to 82 (72±5) years, were examined by gastroscopy in the Second Affiliated Hospital of Hainan Medical University, who American Society of Anesthesiologists (ASA) was grade Ⅰ or Ⅱ. Sufentanil 0.1 μg/kg and test dose Remimazolam were injected intravenously, and the initial dose of Remimazolam was 0.17 mg/kg. The dose of the next patient was determined according to the modified Dixon sequential method. If the former patient had a positive reaction during gastroscopy, such as cough, nausea, vomiting and/or body movement reaction occurred when the gastroscope was placed into the pharynx or in the 2 min, the next patient would increase the dose, otherwise, the dose would be reduced. The dose increase and decrease gradient of Remimazolam was 0.01 mg/kg, and the test was stopped after 12 times of return. At the same time, the occurrence of adverse reactions during anesthesia was observed. Results: A total of 39 elderly patients completed the trial, of which 21 were effective and 18 were ineffective. When the elderly patients were sedated by gastroscopy, the ED50 of single intravenous injection of Remimazolam was 0.153 mg/kg (95%CI:0.151-0.154 mg/kg) and the ED95 was 0.164 mg/kg (95%CI:0.160-0.166 mg/kg). The total dose of Remimazolam was (10.6±2.8) mg, the recovery time was (10.0±3.4) min, and the stay time in resuscitation room was (8.2±2.6) min. During anesthesia, nausea and vomiting occurred in 1 case, transient hypotension in 4 cases, and no other adverse reactions were found. Conclusion: The ED50 of Remimazolam during gastroscopic sedation in elderly patients is 0.153 mg/kg, ED95 is 0.162 mg/kg, and the incidence of adverse reactions is low.

[Re-evaluation of the diagnostic value and optimal cutoff point of captopril challenge test in diagnosis of primary aldosteronism]

Objective: The aim of the present study was to re-evaluate the diagnostic value and optimal cutoff point of captopril challenge test (CCT) in diagnosis of primary aldosteronism (PA). Methods: This is a retrospective study. All patients with a high risk for PA underwent screening test, and then proceeded to CCT and fludrocortisone suppression test (FST) on different days. The FST was used as a reference standard for PA. The plasma renin concentration (PRC) and plasma aldosterone concentration (PAC) were measured with an automated chemiluminescence immunoassay. Random number method was performed in the patients with unilateral primary aldosteronism (UPA), in order to make the proportion of the analyzed UPA in PA was 35%. Receiver operating characteristic (ROC) analyses were performed to compare diagnostic accuracy. Results: A total of 543 patients with 400 PA patients and 143 essential hypertension (EH) patients were enrolled. The diagnostic value of post-CCT PAC was significantly higher than that of the post-CCT plasma aldosterone-renin ratio (ARR), and that of the PAC suppression percentage, respectively. The area under the ROC curve (AUC_ROC) was 0.86 (0.83, 0.89) for PAC, 0.78 (0.74, 0.82) for ARR, and 0.62 (0.56, 0.67) for the PAC suppression percentage (all P<0.01), respectively. The optimal cutoff point of post-CCT PAC for PA was 110 ng/L, in which the sensitivity and specificity were 73.25% and 79.02%, respectively. The diagnostic efficiency of post-CCT PAC was not improved either in combination with PAC suppression percentage or in combination with post-CCT ARR. Conclusions: CCT is a useful test for the confirmation of PA. PAC level of 110 ng/L at 2 h after 50 mg of captopril is recommended as an optimal cutoff point for the diagnosis of PA.

Axially Chiral Bis-Cycloplatinated Binaphthalenes and Octahydro-Binaphthalenes for Efficient Circularly Polarized Phosphorescence in Solution-Processed Organic Light-Emitting Diodes

A new series of axially chiral binuclear Pt(II) complexes with bridging ligands of binaphthalenes and octahydro-binaphthalenes and auxiliary ligands of β-diketones were designed and prepared. These complexes, identified by spectral and electrochemical methods and single-crystal X-ray diffraction, emit an orange-red phosphorescence with a quantum yield up to 21% and 70% in solution and solid, respectively, due to the effect of steric hindrance from bridging ligands and the 2,3-position extension of chiral axis planes. They can be used as emitters in solution-processed organic light-emitting diodes to achieve luminance efficiency, asymmetry factor, and external quantum efficiency up to 5.4 cd A^-1, 3.0 × 10^-3, and 3.1%, respectively. Moreover, the essential relationships between their chemical structures and luminescence quantum efficiency and asymmetry factor are discussed, which affords explicit insights for designing circularly polarized luminescent materials and devices.

Dual Defect-Passivation Using Phthalocyanine for Enhanced Efficiency and Stability of Perovskite Solar Cells

Semiconducting molecules have been employed to passivate traps extant in the perovskite film for enhancement of perovskite solar cells (PSCs) efficiency and stability. A molecular design strategy to passivate the defects both on the surface and interior of the CH₃ NH₃ PbI₃ perovskite layer, using two phthalocyanine (Pc) molecules (NP-SC₆ -ZnPc and NP-SC₆ -TiOPc) is demonstrated. The presence of lone electron pairs on S, N, and O atoms of the Pc molecular structures provides the opportunity for Lewis acid-base interactions with under-coordinated Pb²⁺ sites, leading to efficient defect passivation of the perovskite layer. The tendency of both NP-SC₆ -ZnPc and NP-SC₆ -TiOPc to relax on the PbI₂ terminated surface of the perovskite layer is also studied using density functional theory (DFT) calculations. The morphology of the perovskite layer is improved due to employing the Pc passivation strategy, resulting in high-quality thin films with a dense and compact structure and lower surface roughness. Using NP-SC₆ -ZnPc and NP-SC₆ -TiOPc as passivating agents, it is observed considerably enhanced power conversion efficiencies (PCEs), from 17.67% for the PSCs based on the pristine perovskite film to 19.39% for NP-SC₆ -TiOPc passivated devices. Moreover, PSCs fabricated based on the Pc passivation method present a remarkable stability under conditions of high moisture and temperature levels.

Fabrication of copper phthalocyanine/reduced graphene oxide nanocomposites for efficient photocatalytic reduction of hexavalent chromium

Copper(II) phthalocyanine (CuPc) and non-peripheral octamethyl-substituted copper(II) phthalocyanine (N-CuMe₂Pc) were combined with reduced graphene oxide (rGO) via a precipitation method to form CuPc/rGO and N-CuMe₂Pc/rGO nanocomposites, respectively. CuPc nanorods are distributed on rGO, and N-CuMe₂Pc exists as nanorods and nanoparticles on rGO. The Cr(VI) removal ratio of N-CuMe₂Pc/rGO exposed in simulated sunlight is 99.0% with a fast photocatalytic reaction rate of 0.0320 min^-1, which is approximately 1.5 times faster than that of CuPc/rGO (0.0215 min^-1) and far surpasses that of pristine phthalocyanine and rGO. As an electron acceptor, rGO can suppress the recombination of photo-induced electron-hole pairs and also can provide a large surface area for Cr(VI) removal, both of which are beneficial to the reducing capacity of the nanocomposites. The higher removal efficiency of N-CuMe₂Pc/rGO compared with that of CuPc/rGO is attributed to the higher specific surface area, higher light harvesting, higher conductivity and more negative lowest unoccupied molecular orbital level of N-CuMe₂Pc/rGO. The N-CuMe₂Pc/rGO nanocomposite shows excellent photochemical recyclability which is essential for application in wastewater treatment.

[Prevalence and clinical characteristics of obstructive sleep apnea in patients with primary hyperaldosteronism]

Objective: To explore the proportion of obstructive sleep apnea (OSA) in primary aldosteronism (PA) in Chinese population and compare the clinical characteristics between PA patients with OSA and those without. Methods: A total of 96 patients diagnosed with PA from September 2015 to November 2018 were recruited in this study. OSA was screened by cardio-respiratory polygraphy. According to the apnea hypopnea index (AHI), the patients were divided into PA with OSA group (AHI ≥5 times) and PA without OSA group (AHI<5 times). Results: Among all patients (96), 69 (71.9%) were with OSA, among them 22 patients (22.9%) were with mild OSA, 17 patients (17.7%) were with moderate OSA and 30 patients (31.3%) were with severe OSA. Compared with the patients without OSA, the patients with OSA were elder, and had higher levels of body mass index (BMI), waist circumference (WC), hip circumference (HC), creatinine (CR) and glycosylated haemoglobin (HbA1c) (P<0.05), but lower concentrations of plasma aldosterone (PAC), supine aldosterone renin concentration ratio(ARR) and the PAC after the diagnosis test (P<0.05). Spearman correlation analyses showed that BMI, WC, HC, CR and HbA1c were positively correlated with AHI (P<0.05), while high-density lipoproteincholesterol (HDL-C), supine-PAC and saline infusion test(SIT)-post PAC were negatively correlated with AHI (P<0.05). Conclusions: The proportion of OSA in PA patients is relatively high (71.9%). Metabolic abnormalities are more common in PA patients with OSA, indicating that screening for OSA should be carried out routinely in PA patients.

Molecular Design Strategy in Developing Titanyl Phthalocyanines as Dopant-Free Hole-Transporting Materials for Perovskite Solar Cells: Peripheral or Nonperipheral Substituents?

We demonstrate a molecular design strategy to enhance the efficiency of phthalocyanine (Pc)-based hole-transporting materials (HTMs) in perovskite solar cells (PSCs). Herein, two titanyl phthalocyanine (TiOPc) derivatives are designed and applied as dopant-free HTMs in planar n-i-p-structured PSCs. The newly developed TiOPc compounds possess eight n-hexylthio groups attached to either peripheral (P-SC₆-TiOPc) or nonperipheral (NP-SC₆-TiOPc) positions of the Pc ring. Utilizing these dopant-free HTMs in PSCs with a mixed cation perovskite as the light-absorbing material and tin oxide (SnO₂) as the electron-transporting material (ETM) results in a considerably enhanced efficiency for NP-SC₆-TiOPc-based devices compared to PSCs using P-SC₆-TiOPc. Hence, all of the photovoltaic parameters, including power conversion efficiency (PCE), fill factor, open-circuit voltage, and short-circuit current density, are remarkably improved from 5.33 ± 1.01%, 33.34 ± 3.45%, 0.92 ± 0.18 V, and 17.33 ± 2.08 mA cm^-2 to 15.83 ± 0.44%, 69.03 ± 1.59%, 1.05 ± 0.01 V, and 21.80 ± 0.36 mA cm^-2, respectively, when using the nonperipheral-substituted TiOPc derivative as the HTM in a PSC. Experimental and computational analysis suggests more compact molecular packing for NP-SC₆-TiOPc than P-SC₆-TiOPc in the solid state due to stronger π-π interactions, leading to thin films with better quality and higher performance in hole extraction and transportation. PSCs with NP-SC₆-TiOPc also offer much higher long-term stability than P-SC₆-TiOPc-based devices under ambient conditions with a relative humidity of 75%.

Ultrasonic-Assisted Wet Chemistry Synthesis of Ultrafine SnO2 Nanoparticles for the Electron-Transport Layer in Perovskite Solar Cells

SnO₂ was recently employed as an efficient electron-transport layer (ETL) in perovskite solar cells (PSCs) and high power conversion efficiencies (PCEs) have been reported. However, it is still challenging to fabricate SnO₂ thin films through facile solution-based synthesis at low temperature (<150 °C) to be compatible with the large scale module fabrication, especially for flexible devices. Here, we report a low temperature solution-based method for preparation of SnO₂ nanoparticles. Ultrasonic-assisted wet chemistry synthesis of ultrafine SnO₂ nanocrystals with particle size ranging from 2 to 5 nm was achieved by employing a SnCl₄ ⋅5 H₂ O solution in a mixed ethanol-water solution and with no annealing step. The crystallinity and microstructure of the SnO₂ nanoparticles were investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM), as well as selected area electron diffraction (SAED) analysis. The added water in ethanol and increased pH values were demonstrated as two key factors to successful fabrication of highly crystallized samples with high reproducability. An efficiency of 16.56 % was achieved for PSCs based on SnO₂ nanoparticles synthesized by ultrasonic-assisted wet chemistry.

Soluble hexamethyl-substituted subphthalocyanine as a dopant-free hole transport material for planar perovskite solar cells

Boron subphthalocyanine (SubPc) has special physical and chemical properties, originating from its non-centrosymmetric, near-planar taper structure and large conjugated system; it can act as an alternative to the small molecule hole-transporting material 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene in perovskite solar cells (PSCs). To achieve a higher solubility in common organic solvents and a more suitable highest occupied molecular orbital energy level that aligns with the valence band of the perovskite material, a SubPc molecule with a hexamethyl substitution at its peripheral position (Me6-SubPc) was successfully designed and synthesized in a one-step method. Completely solution processed PSCs were fabricated with only a small hysteresis, a power conversion efficiency of 6.96% and Voc of 0.986 V.

Improvement of the photovoltaic parameters of perovskite solar cells using a reduced-graphene-oxide-modified titania layer and soluble copper phthalocyanine as a hole transporter

Graphene modified mesoporous titania for perovskite solar cells.

[Clinical study of aged patients with secondary benign paroxysmal positional vertigo]

Objective: To investigate the clinical features and evaluate the efficacy of manual reduction in treatment of age patients with secondary benign paroxysmal positional vertigo (s-BPPV). Methods: Thirty-two cases of aged patients ( the s-BPPV group: including 19 cases of female and 13 males, age from 60 to 86 years old)with secondary benign paroxysmal positional vertigo from Jul. 2013 to Sep. 2015 in our hospital were retrospectively analyzed. The results were compared with 121 patients( the primary group: including 82 cases of female and 39males, aged from 60 to 86 years old)with aged primary benign paroxysmal positional vertigo(p -BPPV). All the patients were followed up for 12 months. Statistical data analysis was carried out with SPSS 19.0. Results: 20.92%(32/153)of all the observed elderly patients with BPPV was the aged s-BPPV. The sex ratio and onset age had no significant difference between the two groups(χ(2)=0.79, P>0.05; t=0.37, P>0.05). The rate of two or more semicircular canal involvement in the secondary group(21.88%) was higher than that in primary group(6.61%)(χ(2)=6.67, P<0.05). Bilateral semicircular canals were involved in 5 of the 32 cases in secondary group(15.63%) and 4 of the 121 cases in aged primary group(3.31%), The difference was significant(χ(2)=6.94, P<0.05). The effective rate after first manual reduction was 57.50%(23/40)in secondary group and 82.31%(107/130)in primary group, the difference was significant(χ(2)=10.46, P<0.05). The total effective rate were 87.50%(35/40) after more than once manual reduction in secondary group and 91.54%(119/130) in primary group, the difference was not significant(χ(2)= 0.59, P>0.05). The numbers of circulation of the first successful manual reduction management were (3.9±1.3)times in secondary group and (2.1±1.1)times in primary group, the difference was significant(t=3.15, P<0.05). The recurrence rate was 37.50%(15/40) in the secondary group and 16.15%(21/130)in primary group after during follow-up for 12 months, the difference was statistically significant(χ(2)=8.35, P<0.05). Conclusions: It's shown that the aged patients with secondary BPPV is not rare in clinical practice, sudden deafness and head trauma are frequent more than other reasons. The aged patients with secondary BPPV are prone to injury in multi-semicircular and bilateral canal compared with the primary BPPV. The effective rate after first manual reduction of secondary BPPV is lower than primary BPPV, it's needed more circulation of first success in manual reduction management. The total effective rates are not significant in two groups and recurrence rate is relatively high in secondary group.

[Immune checkpoint inhibitor therapy in advanced head and neck cancer]

Immune checkpoint inhibitor therapy, which targets regulatory pathways in T cells to enhance antitumor immune responses, improves the life quality of cancer patients and has joined the ranks of surgery, radiation, and chemotherapy to become a major choice for cancer therapy. Over the past few years, multiple exciting results have been obtained on checkpoint inhibitor therapy in advanced head and neck cancer. However, questions such as patient selection and biomarkers for assessing the therapy are largely unsolved. Herein, we briefly review recent findings in checkpoint inhibitor therapy for advanced head and neck cancer. We will also discuss possible mechanism, safety, combination therapy, and side effects for the therapy. Checkpoint inhibitor therapy has led to important clinical advances and will provide a new weapon against cancer.

Dopant-Free Hole-Transport Materials Based on Methoxytriphenylamine-Substituted Indacenodithienothiophene for Solution-Processed Perovskite Solar Cells

Solution-processed hole transporting materials (HTMs) that are dopant-free show promise for use in low-cost, high-performance perovskite solar cells (PSCs). The highest-efficiency PSCs use organic HTMs, many of which have low mobilities and therefore require doping, which lowers the device stability. Additionally, these materials are not easily scaled because they often require complicated synthesis. Two new HTMs (IDT-TPA and IDTT-TPA) were synthesized, which contained either an extended fused-ring indacenodithiophene (IDT) or indacenodithienothiophene (IDTT) core and strong electron-donating methoxytriphenylamine (TPA) groups as the end-capping units. The extended conjugation in the backbone of IDTT-TPA resulted in stronger π-π interactions (3.321 Å) and a higher hole mobility of 6.46×10^-4  cm²  V^-1  s^-1 when compared with that of IDT-TPA (9.53×10^-5  cm²  V^-1  s^-1 ). A dopant-free, planar PSC that contained IDTT-TPA was fabricated and exhibited a high power conversion efficiency (PCE) of 15.7 %. This cell exhibited a higher PCE and less hysteresis than devices that contained IDT-TPA.

Facile synthesis of a dopant-free hole transporting material with a phenothiazine core for planar perovskite solar cells

PTZ-TPA was incorporated into a CH₃NH₃PbI₃ perovskite solar cell as a dopant-free HTM exhibiting a comparable PCE (14.1%) and higher stability compared with that of HTM Spiro-MeOTAD with dopant (17.1%).

Effect of fluorination on n-type conjugated polymers for all-polymer solar cells

Incorporation of a different number of fluorine atoms on the donor portion of naphthalene diimide (NDI) based donor–acceptor conjugated polymers significantly affected the solar cell's power conversion efficiency from 0.67% to 2.50%.

Effect of compound Maqin decoction on TGF-β1/Smad proteins and IL-10 and IL-17 content in lung tissue of asthmatic rats

In this research, compound Maqin decoction (CMD) has been shown to positively affect in airway inflammation of asthma models. We evaluated the effects of CMD on the expression of transforming growth factor (TGF)-β1/Smad proteins, interleukin (IL)-17, and IL-10 in lung tissue of asthmatic rats. Asthma was induced in a rat model using ovalbumin. After a 4-week treatment with CMD, rats were killed to evaluate the expression of TGF-β1 and Smad proteins in lung tissue. IL-10 and IL-17 levels in lung tissue homogenates were determined by ELISA. The expression of TGF-β1 and Smad3 protein increased, whereas expression of Smad7 protein decreased upon high-dose or low-dose treatment with CMD or by intervention with dexamethasone, compared to the control. There was a significant difference between treatment with a high dose CMD and the control treatment, but no significant difference was found between high-dose CMD treatment and dexamethasone intervention. The expression of TGF-β1 and Smad7 protein increased, whereas the expression of Smad3 protein decreased in the model group compared to other groups. In the CMD high-dose group, low-dose group, and dexamethasone intervention group, the IL-17 concentrations in lung tissue homogenates were decreased, while IL-10 levels were increased. Again, there was a significant difference between CMD high-dose and control treatment, but not between CMD high-dose treatment and dexamethasone intervention. Thus, positive effects of CMD against asthmatic airway remodeling may be due to its regulatory effect on TGF-β1, Smad3, and Smad7 protein levels and on cytokines such as IL-10 and IL-17.

Effects of c-Jun N-terminal kinase on Activin A/Smads signaling in PC12 cell suffered from oxygen-glucose deprivation

Activin A (Act A), a member of transforming growth factor-β (TGF-β) superfamily, is an early gene in response to cerebral ischemia. Growing evidences confirm the neuroprotective effect of Act A in ischemic injury through Act A/Smads signal activation. In this process, regulation networks are involved in modulating the outcomes of Smads signaling. Among these regulators, crosstalk between c-Jun N-terminal kinase (JNK) and Smads signaling has been found in the TGF-β induced epithelial-mesenchymal transition. However, in neural ischemia, the speculative regulation between JNK and Act A/Smads signaling pathways has not been clarified. To explore this issue, an Oxygen Glucose Deprivation (OGD) model was introduced to nerve-like PC12 cells. We found that JNK signal activation occurred at the early time of OGD injury (1 h). Act A administration suppressed JNK phosphorylation. In addition, JNK inhibition could elevate the strength of Smads signaling and attenuate neural apoptosis after OGD injury. Our results indicated a negative regulation effect of JNK on Smads signaling in ischemic injury. Taken together, JNK, as a critical site for neural apoptosis and negative regulator for Act A/Smads signaling, was presumed to be a molecular therapeutic target for ischemia.

Self-aligned, full solution process polymer field-effect transistor on flexible substrates

Conventional techniques to form selective surface energy regions on rigid inorganic substrates are not suitable for polymer interfaces due to sensitive and soft limitation of intrinsic polymer properties. Therefore, there is a strong demand for finding a novel and compatible method for polymeric surface energy modification. Here, by employing the confined photo-catalytic oxidation method, we successfully demonstrate full polymer filed-effect transistors fabricated through four-step spin-coating process on a flexible polymer substrate. The approach shows negligible etching effect on polymeric film. Even more, the insulating property of polymeric dielectric is not affected by the method, which is vital for polymer electronics. Finally, the self-aligned full polymer field-effect transistors on the flexible polymeric substrate are fabricated, showing good electrical properties and mechanical flexibility under bending tests.

Enhanced self-assembled monolayer treatment on polymeric gate dielectrics with ultraviolet/ozone assistance in organic thin film transistors

Chemical vapor deposition (CVD) is utilized to form self-assembled monolayers on polymeric insulators. Ultraviolet/ozone (UVO) treatment is used to enhance the alignment of HMDS monolayer on polymeric insulator surface and a time dependent effect is observed for UVO.

Poly(3-hexylthiophene) nanotubes with tunable aspect ratios and charge transport properties

Regioregular poly(3-hexylthiophene) (RR-P3HT) nanotubes (200 nm in diameter) with tunable aspect ratios from 25 to 300 were prepared using a polymer melt wetting technique. Aspect-ratio tunability was achieved by controlling the wetting behavior of RR-P3HT melts in a template. The crystallinity and chain orientation of RR-P3HT were studied by grazing incidence X-ray diffraction, wide-angle X-ray diffraction, and polarized photoluminescence spectroscopy. Results suggest that RR-P3HT chains in the lamellar structure prefer to be perpendicular to the axis of the RR-P3HT nanotubes, forming a face-on conformation in the RR-P3HT nanotubes that leads to increased carrier mobility of RR-P3HT. Field-effect transistors were fabricated based on a single RR-P3HT nanotube and showed a carrier mobility of 0.14 ± 0.02 cm(2)/V·s.

The strain and thermal induced tunable charging phenomenon in low power flexible memory arrays with a gold nanoparticle monolayer

The strain and temperature dependent memory effect of organic memory transistors on plastic substrates has been investigated under ambient conditions. The gold (Au) nanoparticle monolayer was prepared and embedded in an atomic layer deposited aluminum oxide (Al(2)O(3)) as the charge trapping layer. The devices exhibited low operation voltage, reliable memory characteristics and long data retention time. Experimental analysis of the programming and erasing behavior at various bending states showed the relationship between strain and charging capacity. Thermal-induced effects on these memory devices have also been analyzed. The mobility shows ~200% rise and the memory window increases from 1.48 V to 1.8 V when the temperature rises from 20 °C to 80 °C due to thermally activated transport. The retention capability of the devices decreases with the increased working temperature. Our findings provide a better understanding of flexible organic memory transistors under various operating temperatures and validate their applications in various areas such as temperature sensors, temperature memory or advanced electronic circuits. Furthermore, the low temperature processing procedures of the key elements (Au nanoparticle monolayer and Al(2)O(3) dielectric layer) could be potentially integrated with large area flexible electronics.

Low voltage flexible nonvolatile memory with gold nanoparticles embedded in poly(methyl methacrylate)

We demonstrate air-stable low voltage flexible nonvolatile memory transistors by embedding gold nanoparticles (Au NPs) in poly(methyl methacrylate) (PMMA) as the charge storage element. The solution processability of the nanocomposite is suitable for low-cost large area processing on flexible substrates. The memory transistor exhibits a memory window of 2.1 V, long retention time ( > 10(5) s) with low operating voltage (≤5 V). The memory behavior has been tuned via varying the composition of the fillers (Au NPs), which offers relatively easy processability for different flexible electronics applications. The electrical properties of the memory devices are found to be stable under bending. These findings will be of value for low cost and low voltage advanced flexible electronics.

Microcontact printing of ultrahigh density gold nanoparticle monolayer for flexible flash memories

A uniform monolayer of alkanethiol-protected gold nanoparticle arrays with ultrahigh density have been used as microcontact-printable charge-trapping layers for the application in flexible flash memories. The new devices are compared to two reference devices with a floating gate created by thermal evaporation and electrostatic self-assembly, and show a large memory window, long retention times and good endurance properties.

Structure-charge transport relationship of 5,15-dialkylated porphyrins

5,15-Dialkyl-substituted porphyrins that are symmetrically capped with ethyl (C(2)-Por), butyl (C(4)-Por) and hexyl (C(6)-Por) were synthesized and characterized. Molecular structure versus physical property relationship has been established through the analysis of planar charge transport using thin film transistor (TFT) structure.

Controlled ambipolar charge transport through a self-assembled gold nanoparticle monolayer

An active mechanism for controlling ambipolar charge transport is developed based on self-assembled monolayers of gold nanoparticles. Electron and hole currents are manipulated by controlling the gate bias in order to overcome the intrinsic material limitations. The endurance and retention measurements confirm that this method exhibits good electrical reliability and stability. This solution process approach has potential for applications in large-area printed electronic devices.