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Background: In patients with Cushing's disease, the preoperative identification of pituitary adenomas is crucial to treatment. However, increasing diagnostic accuracy remains an unresolved issue. Purpose: To evaluate the diagnostic accuracy and the impact of readers' experience regarding high‐resolution contrast‐enhanced magnetic resonance imaging (hrMRI) for identifying pituitary adenomas in comparison with conventional contrast‐enhanced MRI (cMRI) and dynamic contrast‐enhanced MRI (dMRI). Study Type: Retrospective. Population: Sixty‐five patients (median age, 39 years; interquartile range [IQR], 28–53 years; 60% females) with treatment‐naïve Cushing's disease. Field Strength/Sequence: 3‐T, seven fast spin echo sequences. Assessment: The diagnostic accuracies of identifying pituitary adenomas on cMRI, dMRI, combined cMRI and dMRI (cdMRI), and hrMRI were independently evaluated by six readers with three experience levels (high: >20 years, modest: 10–20 years, low: <10 years; two readers for each experience level). Readers were asked to localize the lesion, and measure its diameter on the sequence where identified. The reference standard was postoperative histopathology. The impact of readers' experience and interobserver agreement were assessed. Image quality was assessed using a 5‐point Likert scale, including overall image quality, sharpness, and structural conspicuity. Statistical Tests: McNemar's test, Cochran's test, Wilcoxon signed‐rank test, Mann–Whitney U test, and κ statistics for interobserver agreement. A P‐value <0.05 was considered statistically significant. Results: For identifying pituitary adenomas (median diameter, 5 mm; IQR, 4–5 mm), hrMRI had significantly higher sensitivity (87.7%–93.8%) than cMRI, dMRI, and cdMRI (52.3%–75.4%) for readers with different experience levels. The interobserver agreement was moderate (κ = 0.461–0.523). The sensitivity for hrMRI was comparable between readers with different experience levels (P = 0.371). All image quality scores on hrMRI were significantly higher than cMRI and dMRI (5.0 vs. 4.0). Data Conclusion: For identifying pituitary adenomas in patients with treatment‐naïve Cushing's disease, hrMRI may show high diagnostic accuracy and seems not to be affected by readers' experience. Level of Evidence: 3 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

The asymmetric calibration method is a very interesting technology for differential output probes. It has been proven that the asymmetric calibration method (ACM) can broaden the application scenarios of the electromagnetic field dual probe. However, ACM is not verified on a back‐to‐back double‐loop differential magnetic field probing system. This paper calibrates a back‐to‐back double‐loop differential magnetic field probing system by inserting a connector for creating an asymmetry using ACM. The calibration results show that ACM can be used to calibrate an asymmetric back‐to‐back double‐loop differential magnetic field probing system. The calibration results are further verified by measuring the standing wave magnetic field, and the verification results show that the asymmetric calibration method is effective in eliminating the asymmetry of the back‐to‐back double‐loop differential magnetic field probing system and the work frequency band reaches up to 12 GHz. [ABSTRACT FROM AUTHOR]

The rapid development of optoelectronic devices with biomimetic synaptic behavior holds significant potential for neuromorphic visual applications. However, considerable challenges remain including convenient device fabrication and low toxicity materials innovation. Here, a heterojunction phototransistor is constructed using low‐toxic CuZnInSSe (CIZS) colloidal quantum dots and amorphous InGaZnO (IGZO), which demonstrates high specific detectivity of 3.4 × 1015 Jones in visible light spectrum. Moreover, it is found that the photoresponse speed can be controlled via a ligand exchange treatment, through that the response speed can be adjusted from 0.3 to 11 s. This enables the device to operate in two distinct modes: a typical fast sensing mode and a neuromorphic visual mode. In the neuromorphic visual mode, the device's synaptic behavior can be tuned by manipulating light pulse intensity, frequency, wavelength, and gate voltage. As a demonstration, a phototransistor array effectively implements image pre‐processing functions, including color recognition, visual memorizing, and forgetting. [ABSTRACT FROM AUTHOR]

In order to comply with ultra‐low emission requirements and further reduce the concentration of SO2 emissions from coal‐fired power plants, a novel distributor has been proposed to enhance the uniformity of fluid distribution in the desulfurization tower. The distributor ensures that the inlet flue gas comes into even contact with the slurry droplets ejected from the nozzle, thereby improving the removal efficiency of SO2. The research focuses on a circular desulfurization tower using ammonia‐based desulfurization. To study the enhancement of non‐empty tower desulfurization efficiency, a CFD‐DPM model based on the Euler–Lagrange method has been established. The accuracy of the model has been verified through comparison with experimental or validated data, ensuring its reliability in predicting the performance of the proposed distributor in enhancing desulfurization efficiency in the circular desulfurization tower. The simulation results demonstrate that the addition of the new inflow gas distributor leads to a significantly thinner flue gas escape zone in the circular desulfurization tower. The flue gas flow velocity at the wall side of the tower, above the distributor, increases by only about 1 m/s with the rise of the horizontal cross section, and there is hardly any flue gas escape zone observed. The addition of the distributor increases the pressure drop in the local area, while optimizing the flow field in other areas and reducing the turbulent dissipation energy, which in turn reduces the full tower pressure drop from 701 to 474 Pa. Additionally, the flue gas at the outlet of the distributor is uniformly dispersed, with gas velocity distribution unevenness values of 0.558, 0.587, and 0.601, respectively, which are 15.9%, 14.0%, and 14.0% lower than the unevenness value of the empty tower spraying, at a depth of 1 m below each spray layer. These improvements in gas flow distribution and pressure drop contribute to better control of ammonia escape and aerosol phenomenon, while also enhancing the desulfurization efficiency. [ABSTRACT FROM AUTHOR]

The de‐embedding calibration method has been proposed to achieve high‐precision calibration for a single port electric field or magnetic field probe, which can effectively eliminate the calibration ripple. However, the method's effectiveness for a four‐port calibration system has not been verified yet. In this paper, a four‐port de‐embedding calibration method with a differential magnetic field probe is proposed, and its effectiveness is proved. Two symmetric grounded coplanar waveguide transmission lines are applied in the proposed method to solve the ABCD‐matrix of the embedded part of the calibrator. The de‐embedded S‐parameter model of the four‐port calibration system for differential magnetic field probe can be obtained. The calibration results indicate that the proposed method can also reduce the calibration ripple and compensate for the attenuation caused by the calibrator. Compared with the traditional calibration method using a microstrip line calibrator, the ripples of the proposed method can be reduced by 34%. The analysis results of the frequency interval of the ripple (FIR) in different methods show that the de‐embedding method can reduce the FIRs (except around 1.2 GHz) caused by the reflection of the calibrator and retain the FIR (about 1.2 GHz) caused by the reflection of the probe itself. [ABSTRACT FROM AUTHOR]

An ultrawideband de‐embedding calibration method (DCM) for a dual probe is proposed in this paper. Different from the conventional calibration method (CCM), in which a microstrip calibrator and the dual probe form a three‐port calibration network, the proposed calibration system is a four‐port network. By using two different lengths of grounded coplanar waveguide (GCPW) calibrators, namely line‐kit and through‐kit, the de‐embedded S $S$‐parameter model of the calibration network is obtained. Measured results show that the ripple of the DCM with GCPW reduced by 59% of the CCM with the microstrip calibrator, and the phase delay has been almost compensated. In addition, the proposed method reduces the attenuation by approximately 0.7 dB at 10 GHz and 1.15 dB at 20 GHz. The calibration results indicate that the working frequency of the DCM is up to 22 GHz. [ABSTRACT FROM AUTHOR]

Background: Multidelay arterial spin labeling (ASL) generates time‐resolved perfusion maps, which may provide sufficient and accurate hemodynamic information in carotid stenosis. Purpose: To use imaging markers derived from multidelay ASL magnetic resonance imaging (MRI) and to determine the optimal strategy for predicting cerebral hyperperfusion after carotid endarterectomy (CEA). Study Type: Prospective observational cohort. Subjects: A total of 79 patients who underwent CEA for carotid stenosis. Field Strength/Sequence: A 3.0 T/pseudo‐continuous ASL with three postlabeling delays of 1.0, 1.57, and 2.46 seconds using fast‐spin echo readout. Assessment: Cerebral perfusion pressure, antegrade, and collateral flow were scored on a four‐grade ordinal scale based on preoperative multidelay ASL perfusion maps. Simultaneously, quantitative hemodynamic parameters including cerebral blood flow (CBF), arterial transit time (ATT), relative CBF (rCBF) and relative ATT (rATT; ipsilateral/contralateral values) were calculated. On the CBF ratio map obtained through dividing postoperative by preoperative CBF map, regions of interest were placed covering ipsilateral middle cerebral artery territory. Three neuroradiologists conducted this procedure. Cerebral hyperperfusion was defined as a CBF ratio >2. Statistical Tests: Weighted κ values, independent sample t test, chi‐square test, Mann–Whitney U‐test, multivariable logistic regression analysis, receiver‐operating characteristic curve analysis, and Delong test. Significance level was P < 0.05. Results: Cerebral hyperperfusion was observed in 15 (19%) patients. Higher blood pressure (odd ratio [OR] = 1.08) and carotid near‐occlusion (NO; OR = 7.31) were clinical risk factors for postoperative hyperperfusion. Poor ASL perfusion score (OR = 37.33), decreased CBF (OR = 0.74), prolonged ATT (OR = 1.02), lower rCBF (OR = 0.91), and higher rATT (OR = 1.12) were independent imaging predictors of hyperperfusion. ASL perfusion score exhibited the highest specificity (95.3%), while CBF exhibited the highest sensitivity (93.3%) for the prediction of hyperperfusion. When combined with ASL perfusion score, CBF and ATT, the predictive ability was significantly higher than using blood pressure and NO alone (AUC: 0.98 vs. 0.78). Data Conclusions: Multidelay ASL can accurately predict cerebral hyperperfusion after CEA with high sensitivity and specificity. Evidence Level: 2 Technical Efficacy: Stage 5 [ABSTRACT FROM AUTHOR]

Although considerable efforts towards directly converting syngas to liquid fuels through Fischer–Tropsch synthesis have been made, developing catalysts with low CO2 selectivity for the synthesis of high‐quality gasoline remains a big challenge. Herein, we designed a bifunctional catalyst composed of hydrophobic FeNa@Si‐c and HZSM‐5 zeolite, which exhibited a low CO2 selectivity of 14.3 % at 49.8 % CO conversion, with a high selectivity of 62.5 % for gasoline in total products. Molecular dynamic simulations and model experiments revealed that the diffusion of water molecules through hydrophilic catalyst was bidirectional, while the diffusion through hydrophobic catalyst was unidirectional, which were crucial to tune the water‐gas shift reaction and control CO2 formation. This work provides a new fundamental understanding about the function of hydrophobic modification of catalysts in syngas conversion. [ABSTRACT FROM AUTHOR]

SUMMARY: 5′‐3′ exoribonucleases (XRNs) play crucial roles in the control of RNA processing, quality, and quantity in eukaryotes. Although genome‐wide profiling of RNA decay fragments is now feasible, how XRNs shape the plant mRNA degradome remains elusive. Here, we profiled and analyzed the RNA degradomes of Arabidopsis wild‐type and mutant plants with defects in XRN activity. Deficiency of nuclear XRN3 or cytoplasmic XRN4 activity but not nuclear XRN2 activity greatly altered Arabidopsis mRNA decay profiles. Short excised linear introns and cleaved pre‐mRNA fragments downstream of polyadenylation sites were polyadenylated and stabilized in the xrn3 mutant, demonstrating the unique function of XRN3 in the removal of cleavage remnants from pre‐mRNA processing. Further analysis of stabilized XRN3 substrates confirmed that pre‐mRNA 3′ end cleavage frequently occurs after adenosine. The most abundant decay intermediates in wild‐type plants include not only the primary substrates of XRN4 but also the products of XRN4‐mediated cytoplasmic decay. An increase in decay intermediates with 5′ ends upstream of a consensus motif in the xrn4 mutant suggests that there is an endonucleolytic cleavage mechanism targeting the 3′ untranslated regions of many Arabidopsis mRNAs. However, analysis of decay fragments in the xrn4 mutant indicated that, except for microRNA‐directed slicing, endonucleolytic cleavage events in the coding sequence rarely result in major decay intermediates. Together, these findings reveal the major substrates and products of nuclear and cytoplasmic XRNs along Arabidopsis transcripts and provide a basis for precise interpretation of RNA degradome data. [ABSTRACT FROM AUTHOR]

Flexible direct X‐ray detectors based on perovskites have great potential for X‐ray imaging due to their high sensitivity, low detection limit, low‐cost, and large‐area fabrication. However, these detectors perform inefficiently at X‐ray‐to‐current conversion because of inadequate functional layer thickness and charge‐carrier recombination. Here, the fabrication of an integrated, self‐powered X‐ray detector based on CsPbBr3 quantum dots and a MAPbI3 photoelectric conversion layer embedded with perylene diimide molecules is reported. In addition to optimizing crystal domain formation and charge carrier extraction, the perylene diimide molecules also improve the electron mobility of MAPbI3 films by twofold. The integrated perovskite‐based X‐ray detector has a sensitivity of 143 169 ± 848 µC Gyair−1 cm−2 and a detection limit of 30.77 nGy s−1. The perylene diimide molecule at the grain boundary of MAPbI3 shows defect passivation and charge collection characteristics, leading to stable output over 30 bending cycles. This hybrid molecular approach provides insight into a general method to modify device performance using perylene diimide‐integrated detectors for X‐ray imaging of 3D objects with curved surfaces. [ABSTRACT FROM AUTHOR]

Due to the fast phase separation kinetics and small feature size, the self‐assembly of giant molecules has attracted lots of attention. However, there is not much study on multicomponent giant surfactants. In this work, through a modular synthetic strategy, different polyhedral oligomeric silsesquioxane (POSS)‐based molecular nanoparticles are installed with diverse functionalities (hydrophobic octavinyl POSS (VPOSS), hydrophilic dihydroxyl‐functionalized POSS (DPOSS), and omniphobic perfluoroalkyl‐chain‐functionalized POSS (FPOSS)) on the ends of one polystyrene (PS) chain to build up a series of triblock bola‐form giant surfactants denoted as XPOSS–PSn–FPOSS (X represents V or D). The target molecules are prepared by a combination of atom transfer radical polymerization (ATRP), esterification, as well as Cu(I)‐catalyzed azide‐alkyne cycloaddition (CuAAC) and thiol–ene "click" reactions. These macromolecules are thoroughly characterized by combined technologies including nuclear magnetic resonance (NMR), size exclusion chromatography (SEC), and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) analyses. It is revealed by small angle X‐ray scattering (SAXS) and transmission electron microscopy (TEM) that VPOSS–PSn–FPOSS adopts a two‐phase separation scenario where VPOSS and POSS are segregated in one phase. DPOSS–PSn–FPOSS with a third hydrophilic DPOSS shows a three‐phase separation scenario, where highly ordered phase structures are difficult to develop owing to the competition of mutual phase separation processes and may be trapped in kinetically metastable states. [ABSTRACT FROM AUTHOR]

Emerging Pb‐based photovoltaic (PV) technologies, including in particular solution processed halide perovskite solar cells (PSCs) and Pb chalcogenide quantum dot solar cells (QDSCs), are among the most promising next‐generation PV technologies for a range of disruptive energy and electronic applications. However, the potential toxicity and leakage of hazardous Pb species have become one of the main barriers to their large‐scale application. When solar cells are subject to physical damage or failure of encapsulation, rapid leakage of Pb may occur, which can be accelerated by exposure to external environmental weathering conditions such as rainfall and elevated temperature. Herein, an in‐depth investigation on the essential role of Pb in PSCs and QDSCs, as well as common causes of Pb leakage, is undertaken. The hazardous effects of Pb toxicity on soil plants, bacteria, animals, and human cells are also evaluated. Recent progress in developing effective strategies for Pb leakage reduction, such as Pb‐free or Pb‐less perovskite materials, device architecture design, encapsulation absorbers for PSCs, and core–shell structure and ligand exchange method for QDSCs, in addition to Pb recycling strategies of end‐of‐life solar cells are summarized. This review provides quantitative insights into the future development of eco‐friendly emerging Pb‐based PV technologies. [ABSTRACT FROM AUTHOR]

Pt‐based electrocatalysts exhibit high performance toward hydrogen evolution reaction (HER) since they can boost sluggish kinetics of water dissociation. To develop efficient Pt catalysts in nonacidic media, Pt electrocatalysts with a Rh core and a shell of a few Pt atomic layers (Rh@PtnL, n = 1, 2, 2.6) are designed. Ultrathin Pt atomic layers on a Rh core modulate electronic structures of Rh@PtnL electrocatalysts, generating a combined effect of ligand, compressive strain, and electron transfer. The Rh@PtnL electrocatalysts thus offer significantly higher HER activity in alkaline and neutral media than the RhPt alloy, Rh/C, and commercial Pt/C catalysts. The overpotential of a Rh@Pt2L electrocatalyst is only 5 mV at 10 mA cm−2 in 1.0 M KOH. The density functional theory calculations confirm that the excellent HER activity of this Rh@Pt2L electrocatalyst in nonacidic media is attributed to an enhanced hydrogen desorption and a decreased energetic barrier during the hydrogen generating process. These Rh@PtnL electrocatalysts shed the light on the design of advanced catalysts to efficiently produce green hydrogen in nonacidic media. [ABSTRACT FROM AUTHOR]

In this study, a near‐field dual probe with a double‐loop structure is designed and characterised. The high‐performance, low‐loss Rogers material and four‐layer printed circuit board are applied to design the double detection loop structure, which increases the detection area and effectively improves the frequency response of the probe. The key parameters of the probe, including the frequency response, calibration factor, sensitivity, spatial resolution, isolation and differential electric field suppression are characterised by a microstrip line. Compared with other dual probes, the proposed probe has better frequency response and higher sensitivity. The magnetic field sensitivity is −90.88 dB A/m/Hz $\sqrt{\mathrm{H}\mathrm{z}}$ and the electric field sensitivity is −46.89 dB A/m/Hz $\sqrt{\mathrm{H}\mathrm{z}}$ at 1 GHz. [ABSTRACT FROM AUTHOR]

Lead halide perovskite solar cells (PSCs) have emerged as a highly promising next‐generation photovoltaic (PV) technology that combines high device performance with ease of processing and low cost. However, the potential leaching of lead is recognized as a major environmental concern for their large‐scale commercialization, especially for application areas with significant overlap with human life. Herein, a quantitative kinetic analysis of the Pb leaching behavior of five types of benchmark PSCs, namely, MAPbI3, FA0.95MA0.05Pb(I0.95Br0.05)3, Cs0.05(FA0.85MA0.15)0.95Pb(I0.85Br0.15)3, CsPbI3, and CsPbI2Br, under laboratory rainfall conditions is reported. Strikingly, over 60% of the Pb contained in the unencapsulated perovskite devices is leached within the first 120 s under rainfall exposure, suggesting that very rapid leaching of Pb can occur when indoor and outdoor PV devices are subject to physical damage or failed encapsulation. The initial Pb leaching rate is found to be strongly dependent on the types of PSCs, pointing to a potential route toward Pb leaching reduction through further optimization of their materials design. The findings offer kinetic insights into the Pb leaching behavior of PSCs upon aqueous exposure, highlighting the urgency to develop robust mitigation methods to avoid a potentially catastrophic impact on the environment for their large‐scale deployment. [ABSTRACT FROM AUTHOR]

For Pt‐WOx‐based catalysts, researchers pay much attention to study the influence of Pt‐WOx interaction on glycerol hydrogenolysis, ignoring the interaction between WOx and support. Herein, four Pt/W/SiZr‐T catalysts with different surface hydroxyl groups on support are prepared and characterized. The results show that bibridged (OHII) and tribridged hydroxyl groups (OHIII) on SiZr‐T supports could react with WOx species through forming Zr−O−W bands and retard the agglomeration of WOx species. The highly dispersed WOx species and Zr−O−W bands are the origination of inherent and in‐situ generated Brønsted acid, which are beneficial for 1,3‐propanediol synthesis. As a result, Pt/W/SiZr‐70 exhibits outstanding performance due to abundant OHII and OHIII on SiZr‐70. The initial space time yield of 1,3‐propanediol on Pt/W/SiZr‐70 reaches 2.280 g1,3‐PDO ⋅ gcat−1 ⋅ h−1, the highest among reported results. This r esearch reveals the role of WOx‐support interaction on glycerol hydrogenolysis and provides a new direction to design Pt‐WOx‐based catalysts for selective hydrogenation reactions. [ABSTRACT FROM AUTHOR]

A phosphine‐mediated reaction for the construction of spirocyclopenta[c]chromene‐indolinones is reported via a Rauhut‐Currier (RC)‐type/acyl transfer/Wittig sequence. This methodology attributes the chemoselective phosphine addition to the alkynoate which generates the phosphorus zwitterion via RC‐type reaction, and that further undergoes O‐acylation to form the seven‐membered betaine intermediate with acyl chloride in the presence of base. Extensive investigations reveal that the exceptional δ‐acylation occurs through the C−O bond cleavage upon the seven‐membered betaine, and the subsequent Wittig reaction preferentially result in the aforementioned spiro compounds. Furthermore, our protocol could also be applicable to different alkynoates to provide a series of spirocyclopenta[c]chromenones bearing privileged skeletons. [ABSTRACT FROM AUTHOR]

Formamidinium lead iodide (FAPbI3) is ideal for highly efficient and operationally stable perovskite solar cells (PSC). However, a primary challenge for FAPbI3 PSC is to suppress the phase transition from the photoactive black phase into the yellow nonperovskite δ‐phase. The preparation of Cs‐containing mixed FAPbI3 perovskite by cation stoichiometric engineering is demonstrated and the influence of the Cs/FA ratio on its phase stability and device performance is discussed. By exploring the optimal ratio of Cs and FA cations in CsxFA1−xPb(I0.94Br0.06)3 perovskite, an inverted planar device with Cs0.17FA0.83Pb(I0.94Br0.06)3 composition shows the best power conversion efficiency (PCE) of 16.5% in an active area of 1.08 cm2. More importantly, the Cs0.17FA0.83Pb(I0.94Br0.06)3 perovskite photoactive layer showed remarkable long‐term stability, maintaining 88.1% of its initial efficiency for 1128 h in the presence of moisture and oxygen and without any encapsulation. The excellent long‐term stability is found to originate from the appropriate tolerance factor and low thermodynamic decomposition energy, which underpins the strong potential for the commercialization of Cs‐containing mixed FAPbI3 PSCs. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: We report herein the precision synthesis and phase behaviors of multi‐tailed B2AB2‐type regio‐isomeric giant surfactants consisting of a hydrophilic polyhedral oligomeric silsesquioxane (POSS) head tethered with four hydrophobic polystyrene (PS) tails. The synthesis was accomplished through two sequential "click" reactions to give a series of regio‐isomeric giant surfactants S2DS2 (where S is short for PS tails and D for hydroxyl‐functionalized POSS) in para‐, meta‐, and ortho‐configurations. Their phase structures and phase behaviors at the columnar‐spherical boundary were investigated with a single PS tail molecular weight of 1.4 kDa. Specifically, the para‐ and meta‐isomers show hexagonally packed cylinders phases with slightly different order‐disorder transition temperatures (~120 °C and ~130 °C) and the ortho‐isomer exhibits an order‐order transition from a kinetically favored, metastable dodecagonal quasi‐crystal phase to a thermodynamically stable sigma phase at ~120 °C, as well as a further transition into the disordered state at ~140 °C. The phase diagram was constructed and their differences were rationalized based on the calculated interfacial area per molecule. This work demonstrates that tiny structural disparity could not only lead to unconventional phase formation in single‐component macromolecules, but also render dynamic and rich phase behaviors in these macromolecular assemblies. [ABSTRACT FROM AUTHOR]

White light emission is of great importance in our daily life as it is the primary source of light indoor and outdoor as well as day and night. Among various materials and lighting technologies, intensive efforts have been made to quantum dots based‐light‐emitting diode (QD‐LEDs, or QLEDs) because of outstanding optical properties, facile synthesis, and bandgap tunability of QDs. Despite the fact that QLEDs are able to present various colors in a visible range, realizing efficient direct white light emission is a challenge as white light emission can only be achievable through stacking and patterning of QD films or mixing of different sizes of QDs. This inevitably involves energy band mismatch at interfaces, leading to degradation of device performance. Here, a new effective method to improve white QLED performances through embedding a ferroelectric islands structure is introduced, which induces an electric field to effectively modulate the energy band at the junction interface. The formation of a favorable energy landscape leads to efficient charge transport, improved radiative recombination, and consequently high external quantum efficiency in the white QLEDs. In addition, it is demonstrated that this new approach is proved to be effective in different color temperatures ranging from 3000 to over 120 000 K. [ABSTRACT FROM AUTHOR]

The low effectiveness factor of catalyst pellet caused by high internal diffusion limitation is a common issue in fixed‐bed reactor. Nevertheless, hierarchical structured catalyst provides a promising solution for the contradiction between reaction activity and diffusion efficiency in large catalyst pellets. Herein, we studied the effect of pore structure parameters of the meso‐macroporous catalyst on Fischer–Tropsch synthesis performances through experiment and pellet scale reaction–diffusion simulation. The pellet simulation firstly elucidated the reason for the significant improvement on activity and product selectivity for the meso‐macroporous catalyst observed in our experiment. Further optimization via pellet simulation indicated the critical influences of wax filling degree and that the perfect matching between reaction and mass transfer rates by increasing macropore size and adjusting porosity within pellet enables the C5+ space–time yield to the maximum. This work could provide a theoretical guideline for the engineering design of the hierarchical structured catalyst pellet. [ABSTRACT FROM AUTHOR]

Indoor photovoltaics (IPVs) have attracted considerable interest for their potential to power small and portable electronics and photonic devices. The recent advancemes in circuit design and device optimizations has led to the power required to operate electronics for the internet of things (IoT), such as distributed sensors, remote actuators, and communication devices, being remarkably reduced. Therefore, various types of sensors and a large number of nodes can be wireless or even batteryless powered by IPVs. In this review, we provide a comprehensive overview of the recent developments in IPVs. We primarily focus on third‐generation solution‐processed solar cell technologies, which include organic solar cells, dye‐sensitized solar cells, perovskite solar cells, and newly developed colloidal quantum dot indoor solar cells. Besides, the device design principles are also discussed in relation to the unique characteristics of indoor lighting conditions. Challenges and prospects for the development of IPV are also summarized, which, hopefully, can lead to a better understanding of future IPV design as well as performance enhancement. [ABSTRACT FROM AUTHOR]

This study aims to evaluate HR‐HPV viral load in the cervical lesion assessment and its diagnostic value on the triage of ASCUS. The three‐step protocol for cervical cancer screening was carried out in 5171 patients from June 2017 to August 2019, and 1620 histopathological results were obtained. The positive rate of HR‐HPV and TCT increased with the aggravation of pathological grades of cervical lesions. The sensitivity and specificity of HR‐HPV (DH3) to detect CIN II+ were 91.91% and 84.46%, respectively. In comparison, the corresponding results of the cytology test were 80.51% and 83.12%. HPV16/18 viral load was positively correlated with the grade of cervical lesions (p < 0.001, r = 0.321). The diagnostic efficiency of AUC by applying HPV16/18 viral load was 0.682 for the diagnosis of CIN II+. The optimal HPV16/18 viral load for predicting CIN II+ was 6.80 RLU/CO (relative light units/cut‐off), with corresponding sensitivity of 48.6%, specificity of 79.7%, and Youden index of 0.283. In the ASCUS population, viral loads were statistically different in HPV16/18 and the other 12 HR‐HPV when compared cervicitis group with CIN I group and CIN II+ group (all p < 0.05). Statistical differences were detected concerning HPV16/18 viral load, contact bleeding status, and smoking status when compared cervicitis group with CIN I group and CIN II+ group (p < 0.05), with a corresponding odds ratio of 1.004, 1.533, and 5.513, respectively. Our findings suggest that HR‐HPV viral load can be regarded as a useful tool to predict the grade of cervical lesions for ASCUS triage. ClinicalTrials.gov ID: NCT03178136. [ABSTRACT FROM AUTHOR]

A simple and effective method to modify Co/Al2O3 catalyst to improve the catalytic performance in Fischer‐Tropsch synthesis reaction is described. It is found that the electron density on the cobalt surface increases via electron donation from the dopant Ba and CN species, leading to an enhanced C5+ selectivity and C3 o/p ratio. However, the presence of Ba increases the cobalt crystalline size while the introduction of CN species leads to the formation of smaller cobalt nanoparticles and greatly increases their dispersion, thus resulting in a different distribution of heavy hydrocarbon products. Our work offers a new avenue to obtain catalyst with high activity and selectivity. [ABSTRACT FROM AUTHOR]

Colloidal quantum dots (QDs) have unique optical and electrical properties with promising applications in next‐generation semiconductor technologies, including displays, lighting, solar cells, photodetectors, and image sensors. Advanced analytical tools to probe the optical, morphological, structural, compositional, and electrical properties of QDs and their ensemble solid films are of paramount importance for the understanding of their device performance. In this review, comprehensive studies on the state‐of‐the‐art metrology approaches used in QD research are introduced, with particular focus on time‐resolved (TR) and spatially resolved (SR) spectroscopy and microscopy. Through discussing these analysis techniques in different QD system, such as various compositions, sizes, and shell structures, the critical roles of these TR‐spectroscopic and SR‐microscopic techniques are highlighted, which provide the structural, morphological, compositional, optical, and electrical information to precisely design QDs and QD solid films. The employment of TR and SR analysis in integrated QD device systems is also discussed, which can offer detailed microstructural information for achieving high performance in specific applications. In the end, the current limitations of these analytical tools are discussed, and the future development of the possibility of interdisciplinary research in both QD fundamental and applied fields is prospected. [ABSTRACT FROM AUTHOR]

Colloidal metal chalcogenide quantum dots (QDs) have excellent quantum efficiency in light–matter interactions and good device stability. However, QDs have been brought to the forefront as viable building blocks in bottom‐up assembling semiconductor devices, the development of QD solar cell (QDSC) is still confronting considerable challenges compared to other QD technologies due to their low performance under natural sunlight, as a consequence of untapped potential from their quantized density‐of‐state and inorganic natures. This report is designed to address this long‐standing challenge by accessing the feasibility of using QDSC for indoor and concentration PV (CPV) applications. This work finds that above bandgap photon energy irradiation of QD solids can generate high densities of excitons via multi‐photon absorption (MPA), and these excitons are not limited to diffuse by Auger recombination up to 1.5 × 1019 cm−3 densities. Based on these findings, a 19.5% (2000 lux indoor light) and an 11.6% efficiency (1.5 Suns) have been facilely realized from ordinary QDSCs (9.55% under 1 Sun). To further illustrate the potential of the MPA in QDSCs, 21.29% efficiency polymer lens CPVs (4.08 Suns) and viable sensor networks powered by indoor QDSCs matrix have been demonstrated. [ABSTRACT FROM AUTHOR]

Flexible capacitors are a promising power source for foldable and biological electronic devices. Although various materials and device structures have been explored, they are still limited by low energy densities and slow rate capabilities compared to their rigid counterparts. Here, asymmetric carbon nanohorns are proposed as an active material to fabricate flexible solid‐state carbon wire (CW)‐based electrochemical supercapacitors (ss‐CWECs) which exhibit high power density and ultra‐low cutoff frequency. By controlling the electric arc reaction at low temperature (77 K), asymmetric single‐wall carbon nanohorns (SWCNHs) are synthesized with high yield. Based on microscopy and electrochemical characterization, the fundamental reaction mechanism in polyvinyl‐based electrolyte system is elucidated, as being associated with deprotonation reaction at acid, base, and elevated temperature conditions. Additionally, by using activated carbon, multi‐walled carbon nanotubes, and SWCNHs as hybrid electrode materials (5:1:1), remarkable specific length capacitance of 48.76 mF cm−1 and charge–discharge stability (over 2000 times cycles) of ss‐CWECs are demonstrated, which are the highest reported to date. Furthermore, a high‐pass filter for eliminating ultra‐low electronic noise is demonstrated, which enables an optical Morse Code communication system to be operated. Current results confirm the SWCNHs as promising materials for high‐performance soft electronics and energy storage applications. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of laminin (LN) located in the basal lamina, which are important components of the peripheral nervous system‐extracellular matrix, on axon regeneration and remyelination. Nerve acellular scaffolds (NASs) (S‐untreated) were prepared using the acellular technique. The active component LN in the NASs was blocked (S‐LN−) or upregulated (S‐LN+); S‐LN+ contained seven times more LN than did the S‐untreated group. The adhesion capacity of Schwann cells (SCs) to the three types of NAS (S‐untreated, S‐LN−, and S‐LN+) was assessed in vitro. Our results showed that the adhesion of SCs to the NASs was significantly reduced in the S‐LN− group, whereas no difference was observed between the S‐LN+ and S‐untreated groups. The pretreated NASs were used to repair nerves in a nerve injury mouse model with the animals divided into four groups (S‐LN− group, S‐untreated group, S‐LN+ group, and autograft group). Two weeks after surgery, although there was no difference in the S‐LN− group, S‐untreated group and S‐LN+ group, the newly formed basal lamina in the S‐LN− group were significantly lower than those in the other two groups. Four weeks after surgery, the S‐LN+ group had higher numbers of newly generated axons and their calibers, more myelinated fibers, thicker myelin sheaths, increased myelin basic protein expression, and improved recovery of neural function compared to those of the S‐LN− and S‐untreated groups, but all of these parameters were significantly worse than those of the autograft group. Downregulation of the LN level in the NAS leads to a reduction in all of the above parameters. [ABSTRACT FROM AUTHOR]

Topological manipulation of waves is at the heart of cutting‐edge metamaterial research. Quadrupole topological insulators were recently discovered in 2D flux‐threading lattices that exhibit higher‐order topological wave trapping at both the edges and corners. Photonic crystals (PhCs), lying at the boundary between continuous media and discrete lattices, however, are incompatible with the present quadrupole topological theory. Here, quadrupole topological PhCs triggered by a twisting degree‐of‐freedom are unveiled. Using a topologically trivial PhC as the motherboard, it is shown that twisting induces quadrupole topological PhCs without flux‐threading. The twisting‐induced crystalline symmetry enriches the Wannier polarizations and leads to the anomalous quadrupole topology. Versatile edge and corner phenomena are observed by controlling the twisting angles in a lateral heterostructure of 2D PhCs. This study paves the way toward topological twist photonics as well as the quadrupole topology in the quasi‐continuum regime for phonons and polaritons. [ABSTRACT FROM AUTHOR]

Indium gallium zinc oxide (IGZO) thin‐film transistors (TFTs) are primary components in active integrated electronics, such as displays and sensor arrays, which heavily involve high‐throughput passivation techniques during multilayer fabrication processes. Though oxide compound semiconductors are commonly used for providing uniform and robust passivation, it usually causes performance degradation on IGZO TFTs during passivation process. Herein, a parylene‐C and aluminum oxide (AlOx) hybrid passivation approach are introduced to reduce the damage during AlOx atomic layer deposition (ALD), which results in high‐performance depletion‐mode IGZO TFT to be fabricated on polyethylene naphthalate (PEN) substrate with enhanced bias stability. Compared with parylene‐C passivation, the hybrid‐passivated IGZO TFTs exhibit excellent saturation mobility (7.9 cm2 (V s)−1), ON/OFF ratio (107), hysteresis window (0.73 V), and bias stability (1.44 and −0.27 V threshold voltage shift, Vds = 20 V). Based on systematic Mott–Schottky and X‐ray diffraction characterizations, it is found that TFT performance enhancement is originated from their doping density variation that resulted from a parylene‐C/ALD‐AlOx microstructural hybridization. Finally, this method is implemented to wafer‐scale integrated circuits with high uniformity and a flexible 10 × 10 IGZO TFT backplane matrix on a PEN substrate (2.5 cm × 2.5 cm). [ABSTRACT FROM AUTHOR]

Immunotherapy aiming to harness the exquisite power of the immune system has emerged as a crucial part of clinical cancer management. However, only a subset of cancer patients responds to current immunotherapy because of low immunogenicity of the tumor cells and immunosuppressive tumor microenvironment. Herein, host–guest prodrug nanovectors are reported for active tumor targeting and combating immune tolerance in tumors. The prodrug nanovectors are designed by integrating hyaluronic acid (HA) and reduction‐labile heterodimer of Pheophorbide A (PPa) and NLG919 into the supramolecular nanocomplexes, where PPa and NLG919 act as a photosensitizer and potent inhibitor of indoleamine 2,3‐dioxygenase 1 (IDO‐1), respectively. Meanwhile, HA is employed to achieve active tumor targeting by recognizing CD44 overexpressed on the surface of tumor cell membranes. Near infrared (NIR) laser irradiation triggers the release of reactive oxygen species to provoke antitumor immunogenicity and intratumoral infiltration of cytotoxic T lymphocytes (CTLs). Meanwhile, the immunosuppressive tumor microenvironment (ITM) is reversed by NLG919‐mediated IDO‐1 inhibition. Combination of photodynamic immunotherapy and IDO‐1 blockade efficiently eradicates CT26 colorectal tumors in the immunocompetent mice. The host–guest nanoplatform capable of eliciting effective antitumor immunity by inactivating inhibitory immune response can be applied to other immune modulators for improved cancer immunotherapy. [ABSTRACT FROM AUTHOR]

The modification of the equilibrium morphology to expose active facets of cobalt nanoparticles is essential for tailoring and controlling its catalytic performance. Periodic density functional theory (DFT) was applied to systematically investigate the structure and stability of exposed facets of hcp Co nanoparticles induced by Ru promoter in order to clarify the facet‐dependent equilibrium morphology of hcp Co nanoparticles stabilized by Ru promoter. The adsorption and migration of Ru atom can give rise to the change of the surface energy of exposed facets, thus affecting the equilibrium morphology of the hcp Co nanoparticles. Selectively exposed the high Miller index facets, such as Co(10‐12), Co(11‐20) and Co(11‐21) surfaces, can be tuned by adding Ru promoter. Our theoretical calculation results show that Co(11‐21) becomes the predominantly exposed facet accompanied with the decrease of exposed Co(10‐10) and Co(10‐11) with the increase of Ru loading. Further experimental studies suggest that the area of selectively exposed the Co(10‐11) surface for uniform Co nanoplates loaded with 3.0 wt % Ru will be reduced, which is in agreement with the theoretical predicted result. This work is helpful to design the desired Co‐based FTS catalysts rationally with well‐controlled surface structure. [ABSTRACT FROM AUTHOR]

The development of flexible displays for wearable electronics applications has created demand for high‐performance quantum dot (QD) light‐emitting diodes (QLEDs) based on QD core@shell structures. Emerging indium phosphide (InP)‐based core@shell QDs show promise as lighting material in the field of optoelectronics because they are environmentally friendly material, can be produced in a cost‐effective manner, and are capable of tunable emission. While efforts have been made to enhance the performance of InP‐based QLED, the stabilities of InP@ZnSeS QDs film and InP@ZnSeS‐based QLED in water/air are not yet fully understood, limiting their practical applications. Herein, a highly durable, flexible InP@ZnSeS QLED encapsulated in an ultrathin film of CYTOP, a solution‐based amorphous fluoropolymer, is demonstrated. The CYTOP‐encapsulated green flexible QLED shows an external quantum efficiency (EQE) of 0.904% and a high luminescence of 1593 cd m−2 as well as outstanding waterproof performance. The flexible device emits strong luminescence after being immersed in water for ≈20 min. Even when subjected to continuous tensile stress with a 5 mm bending radius, the high luminescence is preserved. This waterproof architecture can be a promising strategy for wearable electronics applications. [ABSTRACT FROM AUTHOR]

Combination cancer immunotherapy has shown promising potential for simultaneously eliciting antitumor immunity and modulating the immunosuppressive tumor microenvironment (ITM). However, combination immunotherapy with multiple regimens suffers from the varied chemo‐physical properties and inconsistent pharmacokinetic profiles of the different therapeutics. To achieve tumor‐specific codelivery of the immune modulators, an indocyanine green (ICG)‐templated self‐assembly strategy for preparing dual drug‐loaded two‐in‐one nanomedicine is reported. ICG‐templated self‐assembly of paclitaxel (PTX) nanoparticles (ISPN), and the application of ISPN for combination immunotherapy of the triple negative breast cancer (TNBC) are demonstrated. The ISPN show satisfied colloidal stability and high efficacy for tumor‐specific codelivery of ICG and PTX through the enhanced tumor permeability and retention effect. Upon laser irradiation, the ICG component of ISPN highly efficiently induces immunogenic cell death of the tumor cells via activating antitumor immune response through photodynamic therapy. Meanwhile, PTX delivered by ISPN suppresses the regulatory T lymphocytes (Tregs) to combat ITM. The combination treatment of TNBC with ISPN and αPD‐L1‐medaited immune checkpoint blockade therapy displays a synergistic effect on tumor regression, metastasis inhibition, and recurrence prevention. Overall, the ICG‐templated nanomedicine may represent a robust nanoplatform for combination immunotherapy. [ABSTRACT FROM AUTHOR]

6π electrocyclization has attracted interest in organic synthesis because of its high stereospecificity and atom economy in the construction of versatile 5–7‐membered cycles. However, examples of asymmetric 6π electrocyclization are quite scarce, and have to rely on the use of chiral organocatalysts, and been limited to pentadienyl‐anion‐ and triene‐type 6π electrocyclizations. Described herein is a zinc‐catalyzed formal [4+3] annulation of isoxazoles with 3‐en‐1‐ynol ethers via 6π electrocyclization, leading to the site‐selective synthesis of functionalized 2H‐azepines and 4H‐azepines in good to excellent yields with broad substrate scope. Moreover, this strategy has also been used to produce chiral 2H‐azepines with high enantioselectivities (up to 97:3 e.r.). This protocol not only is the first asymmetric heptatrienyl‐cation‐type 6π electrocyclization, but also is the first asymmetric reaction of isoxazoles with alkynes and the first asymmetric catalysis based on ynol ethers. [ABSTRACT FROM AUTHOR]

Clarifying the facet‐dependent activity of Co3O4 towards C3H8 combustion is of great importance to have a deep understanding of reaction mechanism and develop highly active Co3O4 based catalysts for light hydrocarbon combustion. In this work, four different Co3O4 nanocatalysts which dominantly exposed {100}, {111}, {110} and {112} facets, respectively, were synthesized via hydrothermal method and further tested in C3H8 combustion. The catalytic activity of different crystal planes varied as the order of {111}>{100}>{110}>{112}. The Co3O4 catalyst with {111} facets exhibited the best catalytic performance with T50 and T90 as low as 209 and 239 °C, respectively. DRIFT and DFT calculations revealed that the facile activation of C−H bond on Co3O4 {111} planes is responsible for the high activity. Moreover, the higher activity of lattice oxygens and easy activation of gas phase oxygen could also contribute to the excellent catalytic performance. [ABSTRACT FROM AUTHOR]

Energy harvesting, which converts wasted environmental energy into electricity by utilizing various physical effects, hasattracted tremendous research interests as is one of the key technologies to realize advanced electronics in the future. In this review, we introduce recent progress in the field of hybrid energy harvesting technology. In particular, we focus on a quantum dots (QD)‐based hybrid energy harvesting device. Attributed to fascinating material properties that QD possess, employment of QDs into hybrid energy harvesting has shown great potential for independent and sustainable energy supply.First, an integration of a QD solar cell into a mechanical energy harvester is discussed to harness different types of environmental energy sources simultaneously. Second, a comprehensive explanation of a piezotronic and piezo‐phototronic effect is provided, which is followed by QD‐based piezo‐phototronic applications. Finally, we summarize recent progress that has been made in energy harvesting technology involving a photovoltaic and piezo/triboelectric effect [ABSTRACT FROM AUTHOR]

Photocatalytic production of hydrogen from water can directly convert solar energy into chemical energy storage, which has significant advantages and great promise. As an emerging photosensitizer, the efficiency of quantum dots (QDs) based artificial photosynthetic system have made breakthroughs. In this review, we will give a summary of the development of QDs based photocatalytic hydrogen evolution in these years. First, we highlight different types of hydrogen evolution catalyst combined with QDs; then we focus on the surface modification and heterostructure formation of QDs to improve the photocatalytic efficiency, respectively. In the end, we will propose some Cd‐free QDs and future development of photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

Autologous nerves, artificial scaffolds or acellular nerve scaffolds are commonly used in bridging treatment for peripheral nerve defects. Xenogeneic acellular nerve scaffolds and allogeneic cellular nerve scaffolds have the same structural characteristics. Due to the wider source of raw materials, these latter scaffolds have high‐potential value for applications. However, whether their heterogeneity will affect nerve regeneration is unknown. The current study evaluated the efficiency of xenogeneic acellular nerve scaffolds (XANs) combined with 5‐ethynyl‐2′‐deoxyuridine (EdU)‐labeling of autologous bone marrow‐derived stem cells (BMSCs) for repair of a 1.5 cm gap in rat sciatic nerves. XANs from rabbit tibial nerves were prepared, the structure and components of the scaffolds were evaluated after completely removing the cellular components. Animals were divided into four groups based on graft: the simple XAN group, the XAN + BMSC group, the XAN + Media (from BMSC culture) group, and the autograft group. Serological immune tests showed that XANs induce an immune response in the first 2 weeks after transplantation. Moreover, cell tracking revealed that the proportion of EdU+ cells decreased over time, as shown by the measures at 2 days (70%), 4 days (20%), and 8 days (even <3%) postoperatively. Nerve functional analyses revealed that in contrast to the autograft group results, the XAN‐BMSC, XAN + Media, and XAN groups did not exhibit good restoration of the sciatic functional index (SFI) or electrophysiological results (the peak action potential amplitudes) 12 weeks, postoperatively. However, the XAN‐BMSC and autograft groups demonstrated greater remyelination and increased axon numbers and myelin thickness than the XAN + Media and XAN groups 12 weeks, postoperatively (p <.05). In conclusion, in the early stage of transplantation, XANs induce a certain degree of inflammation. Although the combination of XANs with autologous BMSCs enhanced the number of regenerated axons and the remyelination, the combination did not effectively improve the recovery of nervous motor function. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 3065–3078, 2018. [ABSTRACT FROM AUTHOR]

Type 2 diabetes was usually caused by inadequate secretion of insulin or insulin resistance in tissues and organs. About 90% diabetes belongs to type 2 diabetes, which is seriously harmful to human health. Dipeptidyl Peptidase‐IV (DPP‐IV) target have attracted much attention because of its ability to prevent type 2 diabetes (T2D). Clinical application of chemical synthetic medicines has different degrees of side effects. Therefore, the present evaluation aims to seek DPP‐IV inhibitors as the source of natural products. DPP‐IV inhibitory activities of eight natural products and a structural modification of mangostin (eight chromone of 1–8 and iridoid glycoside for 9) were evaluated by this manuscript at the enzyme level. As a result, three chromones of 2 (a modified mangostin), 3 (mangiferin) and 5 (breviscapin) showed moderate DPP‐IV inhibitory activities with IC50 values of 69.27 μM, 44.19 μM, and 49.53 μM via the use of the fluorescence‐based method (0.25 mM, 0.34 mM and 0.85 mM for the chromogenic substrate method). This study suggests that natural products, which mainly consist by chromone that generated from Mango and Scutellaria baicalensis may have beneficial effects on treating T2D. Two natural products which derived from Mango and Scutellaria baicalensis showed inhibitory activities against DPP‐IV. A modified mangostin was also identified with inhibitory activity. The results indicated that these natural products can play prophylactic or therapeutic roles against T2D (type 2 diabetes) and provided structurally different skeletons to develop new drugs in the treatment of T2D. [ABSTRACT FROM AUTHOR]