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Summary Luminescence-based, polymer-supported oxygen sensors, particularly those based on platinum group complexes, continue to be of analytical importance. Commercial applications range from the macroscopic (e.g. aerodynamic investigations in wind tunnels, monitoring of oxygen concentration during fermentation, and measurement of biological oxygen demand) to the microscopic (e.g. imaging of oxygen in blood, tissue, cells and other biological samples). Problems hindering the design of improved oxygen sensors include non-linear Stern–Volmer calibration plots and the multi-exponentiality of measured lifetime decays, both of which are attributed primarily to heterogeneity of the sensor molecule in the polymer support matrix. Conventional, confocal and two-photon fluorescence microscopy have proven to be invaluable tools with which the microscale heterogeneity and response of luminescence-based oxygen sensors can be investigated and compared to the macroscopic response. Results obtained for three ruthenium(II) α-diimine complexes in polydimethylsiloxane polymer supports indicate the presence of unquenched microcrystals within the polymer matrix that probably degrade oxygen quenching sensitivity and linearity of the Stern–Volmer quenching plot. Two-photon fluorescence microscopy proved most useful for imaging microcrystals within sensor films, and conventional microscopy allowed direct comparison between microscopic and macroscopic sensor response. The implications of the results in the rational design and mass production of luminescence-based oxygen sensors are significant. [ABSTRACT FROM AUTHOR]

Two‐photon high‐speed fluorescence calcium imaging stands as a mainstream technique in neuroscience for capturing neural activities with high spatiotemporal resolution. However, challenges arise from the inherent tradeoff between acquisition speed and image quality, grappling with a low signal‐to‐noise ratio (SNR) due to limited signal photon flux. Here, a contrast‐enhanced video‐rate volumetric system, integrating a tunable acoustic gradient (TAG) lens‐based high‐speed microscopy with a TAG‐SPARK denoising algorithm is demonstrated. The former facilitates high‐speed dense z‐sampling at sub‐micrometer‐scale intervals, allowing the latter to exploit the spatial redundancy of z‐slices for self‐supervised model training. This spatial redundancy‐based approach, tailored for 4D (xyzt) dataset, not only achieves >700% SNR enhancement but also retains fast‐spiking functional profiles of neuronal activities. High‐speed plus high‐quality images are exemplified by in vivo Purkinje cells calcium observation, revealing intriguing dendritic‐to‐somatic signal convolution, i.e., similar dendritic signals lead to reverse somatic responses. This tailored technique allows for capturing neuronal activities with high SNR, thus advancing the fundamental comprehension of neuronal transduction pathways within 3D neuronal architecture. [ABSTRACT FROM AUTHOR]

Cell‐free DNA (cfDNA) fragmentation patterns have immense potential for early cancer detection. However, the definition of fragmentation varies, ranging from the entire genome to specific genomic regions. These patterns have not been systematically compared, impeding broader research and practical implementation. Here, 1382 plasma cfDNA sequencing samples from 8 cancer types are collected. Considering that cfDNA within open chromatin regions is more susceptible to fragmentation, 10 fragmentation patterns within open chromatin regions as features and employed machine learning techniques to evaluate their performance are examined. All fragmentation patterns demonstrated discernible classification capabilities, with the end motif showing the highest diagnostic value for cross‐validation. Combining cross and independent validation results revealed that fragmentation patterns that incorporated both fragment length and coverage information exhibited robust predictive capacities. Despite their diagnostic potential, the predictive power of these fragmentation patterns is unstable. To address this limitation, an ensemble classifier via integrating all fragmentation patterns is developed, which demonstrated notable improvements in cancer detection and tissue‐of‐origin determination. Further functional bioinformatics investigations on significant feature intervals in the model revealed its impressive ability to identify critical regulatory regions involved in cancer pathogenesis. [ABSTRACT FROM AUTHOR]

Patients who have non‐small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations are more prone to brain metastasis (BM) and poor prognosis. Previous studies showed that the tumor microenvironment of BM in these patients is immunosuppressed, as indicated by reduced T‐cell abundance and activity, although the mechanism of this immunosuppression requires further study. This study shows that reactive astrocytes play a critical role in promoting the immune escape of BM from EGFR‐mutated NSCLC by increasing the apoptosis of CD8+ T lymphocytes. The increased secretion of interleukin 11(IL11) by astrocytes promotes the expression of PDL1 in BM, and this is responsible for the increased apoptosis of T lymphocytes. IL11 functions as a ligand of EGFR, and this binding activates EGFR and downstream signaling to increase the expression of PDL1, culminating in the immune escape of tumor cells. IL11 also promotes immune escape by binding to its intrinsic receptor (IL11Rα/glycoprotein 130 [gp130]). Additional in vivo studies show that the targeted inhibition of gp130 and EGFR suppresses the growth of BM and prolongs the survival time of mice. These results suggest a novel therapeutic strategy for treatment of NSCLC patients with EGFR mutations. [ABSTRACT FROM AUTHOR]

With the fast development of communication techniques, over-the-air testing has developed into the main testing method for current communication systems due to its advantages including no cable connection, high measurement efficiency, and independence from environment. OTA testing has become almost the only solution for 5G system testing especially after the popularity of 5G massive multiple-input-multiple-output. In this paper, we summarize the three main methods of OTA testing including the reverberation chamber-based method, the radiation two-step method, and the multiprobe anechoic chamber- (MPAC-) based method, among which we focus on the MPAC method systematically. In the MPAC method, there are two main channel synthesis techniques that have been heavily studied, namely, prefaded signal synthesis and plane wave synthesis. We summarize the current main research based on these two techniques including probe configurations, probe selection algorithms, and probe design based on the PFS technique and the design of plane wave generators based on PWS technique. The main comparisons are made for the performance of different probe selection algorithms and the performance of different plane wave generators as well as the latest advances. [ABSTRACT FROM AUTHOR]

Introduction: Fluorescent high‐performance polymers have been extensively used in designing optoelectronic devices due to their low cost, excellent thermal stability, high mechanical strength, low flammability, good chemical and radiation resistance, and good electronic properties. While conventional organic luminophores fluoresce strongly in dilute solutions, they suffer from undesirable aggregation‐caused quenching in concentrated solutions and in the solid state due to extensive π‐π stacking interactions and formation of delocalized excitons or excimers. This phenomenon leads to non‐radiative decay thus, decreased fluorescence emission of the material in the solid film state, which significantly limits their real‐world application as solid light‐emitting materials. Objectives: To develop new high‐performance polymers with high photo luminescent efficiency, good processability, film‐forming properties, which could potentially be used in the fabrication of optoelectronic devices. Methods: The preparation of the polyimide DiCN‐PI was carried out by a one‐step, high‐temperature solution imidization method. In this procedure, 1,2,4,5‐cyclohexanetetracarboxylic dianhydride and the diamine were polymerized in 1‐methyl‐2‐pyrrolidinone and γ‐butyrolactone co‐solvent at 180°C for 15 hours in the presence of isoquinoline as catalyst. On the other hand, polyamide DiCN‐PA was synthesized according to the direct phosphorylation polycondensation technique described by Yamazaki from diamine and trans‐1,4‐cyclohexanedicarboxylic acid using triphenyl phosphite and pyridine as condensing agents. Results and Discussion: Both polymers were soluble in several polar aprotic solvents and exhibited useful levels of thermal stability. The polymers were emissive with PL emission bands around 555 (bluish‐green) and 498 (cyan) nm in dilute 1‐methyl‐2‐pyrrolidinone solutions for polyimide and polyamide, respectively. In the solid film state, the polymers emit light green and yellow colors, which simulate the PL behavior of their aggregated states, thereby demonstrating aggregation‐induced fluorescence changes. Conclusions: These results indicate that the incorporation of bulky dicyanoarylamine moiety and alicyclic monomer units into the rigid polymer backbones effectively disrupted the planarity of the chain packing which resulted to the fluorescent high‐performance polymers with desired properties for potential optoelectronic applications. [ABSTRACT FROM AUTHOR]

Organic donor‐acceptor (DA) complexes have emerged in recent years as materials of choice for organic binary electronics. The reactivity descriptors derived from the conceptual DFT reveal imidazo[1,2‐a]pyridines as potential donors. Thus, four imidazo[1,2‐a]pyridines were reacted with tetracyanoethylene (TCNE) in 1 : 2 molar ratio to afford four new DA complexes. The spectral studies, namely IR, 1H, 13C, DEPT 135, 2D HMQC NMR, and HRMS were used to establish structures of the products. The UV‐vis. spectroscopy reveals intramolecular charge transfer. All the four compounds fluoresce giving excitation emission fluorescence spectra with a red shift ranging from 64 to 151 nm and quantum yields from 0.004 to 16.35. Unexpectedly, nitro group in one of the products does not act as quencher; instead, it enhances the quantum yield to make it highest in this series. The products exhibit electrical conductivity which increases with temperature. The FESEM and HRTEM images reveal distinct and homogenous surface morphology with holes which facilitate flow of electrons as manifested by electrical conductivity. The powder XRD and SAED results establish the polycrystalline nature of the products. The theoretical studies indicate an alternate donor acceptor stacking pattern. [ABSTRACT FROM AUTHOR]

We report the synthesis of a new pyrene, dipicolinic acid‐based ligand (L1H) and its corresponding multi‐emissive and multifunctional europium complex [Eu(L1)3] that is capable of single component color switchable emission from red to blue and also white. At high concentration (10 mM) the single component system results in near pure white emission (CIE coordinates x,y=0.329, 0.324). Furthermore, the system showed ratiometric oxygen sensing with oxygen significantly quenching the pyrene centered emission but not the Eu3+ emission, resulting in an overall emission color change from blue to red on increasing oxygen content. [ABSTRACT FROM AUTHOR]

Two binuclear heteroleptic CuI complexes, namely Cu−NIR1 and Cu−NIR2, bearing rigid chelating diphosphines and π‐conjugated 2,5‐di(pyridin‐2‐yl)thiazolo[5,4‐d]thiazole as the bis‐bidentate ligand are presented. The proposed dinuclearization strategy yields a large bathochromic shift of the emission when compared to the mononuclear counterparts (M1–M2) and enables shifting luminescence into the near‐infrared (NIR) region in both solution and solid state, showing emission maximum at ca. 750 and 712 nm, respectively. The radiative process is assigned to an excited state with triplet metal‐to‐ligand charge transfer (3MLCT) character as demonstrated by in‐depth photophysical and computational investigation. Noteworthy, X‐ray analysis of the binuclear complexes unravels two interligand π–π‐stacking interactions yielding a doubly locked structure that disfavours flattening of the tetrahedral coordination around the CuI centre in the excited state and maintain enhanced NIR luminescence. No such interaction is present in M1–M2. These findings prompt the successful use of Cu−NIR1 and Cu−NIR2 in NIR light‐emitting electrochemical cells (LECs), which display electroluminescence maximum up to 756 nm and peak external quantum efficiency (EQE) of 0.43 %. Their suitability for the fabrication of white‐emitting LECs is also demonstrated. To the best of our knowledge, these are the first examples of NIR electroluminescent devices based on earth‐abundant CuI emitters. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Organic luminogens with persistent room temperature phosphorescence (RTP) have drawn tremendous attentions due to their promising potentials in optoelectronic devices, information storage, biological imaging, and anti‐counterfeiting. In this work, six triazatruxene‐based lumiogens with different peripheral substituents and configurations are synthesized and systematically studied. The results show that their fluorescence quantum yields in solid states range from 15.73% to 37.58%. Dispersing the luminogens as guest into the host (PPh3) could turn on the persistent RTP, where PPh3 acts as not only a rigid matrix to suppress the non‐radiative transitions of the guest, but also provides energy transfer channels to the guest. The maximum phosphorescence efficiency and the longest lifetime could reach 29.35% and 0.99 s in co‐crystal films of 6‐TAT‐CN/PPh3 and 5‐TAT‐H/PPh3, respectively. Moreover, these host‐guest co‐crystalline films exhibit great potentials in advanced dynamic data encryption and anti‐counterfeiting. This work deepens the insight for low cost, halogen‐free, and facile fabrication of all‐organic persistent RTP materials. [ABSTRACT FROM AUTHOR]

A new sensing strategy towards hydrogen peroxide based on metal coordination polyelectrolyte‐driven self‐assembly of alkynylplatinum(II) 2,6‐bis(benzimidazol‐2′‐yl)pyridine (bzimpy) complex was demonstrated. The cationic in situ‐generated Ag(I)–thiocholine coordination polyelectrolytes were shown to induce the supramolecular self‐assembly of anionic low‐energy red‐emissive alkynylplatinum(II) bzimpy complexes via non‐covalent Pt(II)⋅⋅⋅Pt(II), electrostatic and π–π stacking interactions. The presence of hydrogen peroxide was shown to inhibit the formation of coordination polyelectrolytes and the coordination polyelectrolyte‐induced self‐assembly of platinum(II) complexes. The weakening of Pt(II)⋅⋅⋅Pt(II), electrostatic and π–π stacking interactions was supported by UV‐vis absorption, emission, and resonance light scattering (RLS) studies. The present assay was also applied to probe glucose indirectly based on the enzymatic reaction of glucose oxidase on the substrate. Operating in a label‐free manner, together with the low‐energy red emission and large Stokes shift of alkynylplatinum(II) complexes, these features render the proposed design attractive for biological applications. [ABSTRACT FROM AUTHOR]

The synthesis, structural, spectroscopic characterization, and DFT/TD‐DFT calculations of antimony corroles are reported herein. The studied complexes can be described as [(Corr)SbIII] and [(Corr)(oxo)SbV]2, where Corr is the trianion of corrole. All these complexes are diamagnetic in nature as is evident from sharp peaks with normal chemical shifts in the 1H NMR spectra. Single crystal XRD analysis reveals that the antimony(V) corrole complex is the bis‐μ‐oxo‐bridged dinuclear antimony(V). Both the tetra and hexa‐coordinated [(Corr)SbIII] and [(Corr)(oxo)SbV]2 antimony complexes adopt domed‐structure with weak d‐π electron coupling. The Sb−O bond distances in the co‐facial dimer of [(Corr)(oxo)SbV]2 are 1.9802(16) Å (DFT: 2.0141 Å) (for Sb1−O1), and 1.9639(17) Å (DFT: 1.9957 Å) (for Sb2−O2) respectively. We observed that even though iodosobenzene is frequently used to oxidize [(Corr)SbIII] species, the oxidation of [(Corr)SbIII] is indeed very facile in nature and it even occurred in the air‐equilibrated CHCl3 solution while storing for few days. Excitation of these antimony (III/V) corrole complexes in DCM/MeOH (1 : 1) at 77 K results in red emission with maxima at 640–720 nm. The singlet oxygen production of [(Corr)(oxo)SbV]2 has a quantum yield of 69 % and is two times higher than the analogous [(Corr)SbIII] derivatives. [ABSTRACT FROM AUTHOR]

The reaction of antimony(III) corroles with nitrosonium tetrafluoroborate in the presence of air led to trans‐difluoroantimony(V) 3,17‐dinitro‐corrole complexes. A trans‐dinitrosylantimony(V) corrole compound has been proposed as a possible reaction intermediate that is subsequently converted into a trans‐dinitroantimony(V) corrole product. The formation of these intermediate species has been established via in situ FT‐IR spectra. This trans‐dinitroantimony(V) corrole species can transfer the nitro group to the β‐pyrrole positions (C3 and C17) of the corrole periphery via a radical pathway. The binding of fluoride to the axial positions of antimony(V) corrole occurs via nucleophilic attack of fluoride ion from BF4−. The trans‐difluoroantimony(V) 3,17‐dinitro‐corrole complexes are fully characterized via X‐ray crystallography, UV‐vis, FT‐IR, and NMR spectroscopy. They catalyze oxygenation reactions under photo‐redox conditions in presence of air and light at ambient temperature by forming singlet oxygen. [ABSTRACT FROM AUTHOR]

On 7 June 2021, Juno flew within 1,000 km of Ganymede's surface, partially mapping its ice shell at six frequencies ranging from 0.6 to 22 GHz. The radiance at these frequencies originates from successively deeper layers of the sub‐surface and may reach depths of 24 km at 0.6 GHz. The MWR observations cover a latitude range from 20°S to 60°N and a longitude range from 120°W to 60°E. We present brightness temperature and derived reflectivity maps of Ganymede with a spatial resolution of up to ∼140 km. The microwave brightness temperature at all MWR wavelengths is anti‐correlated with the visible brightness of the terrain. Normalizing the MWR brightness temperatures using a thermal model for the ice shell reveals that the brightest regions are significantly more reflective in the microwave than the dark regions and that all terrain types are more reflective than is expected from a solid ice surface. We suggest that multiple reflections of the colder sky background at sub‐surface interfaces (e.g., fractures) explain the depressed brightness temperatures observed in brighter terrain types. A thin silicate or salt contaminant surface layer, which is significantly more reflective than ice in the microwave, could explain the microwave reflectivity in the dark regions with little to no contribution from sub‐surface fractures. The observed 0.6–1.2 GHz brightness temperature difference suggests an upper bound on the ice shell conducting layer depth of 150 km in the observation area. Plain Language Summary: A microwave radiometer on the NASA Juno mission observed Ganymede's ice shell at frequencies from 0.6 to 22 GHz. Ice is transparent at these microwave frequencies, meaning the radiometer can "see" very deep into the ice. The microwave signal intensity is proportional to the ice temperature but is also affected by cracks and/or thin dust layers in the ice, which lower the microwave signal intensity. The visibly brightest regions on Ganymede are colder, suggesting more sub‐surface cracks than the visibly darker regions. By using models that relate microwave intensity to ice temperature, we infer an ice temperature profile with depth and from that an upper bound on the ice shell conducting layer thickness of 150 km. Key Points: New microwave radiometer observations from 0.6 to 22 GHz constrain thermal/structural properties in the upper 24 km of Ganymede's ice shellBright regions have higher microwave reflectivity than dark regions, possibly due to more numerous and deeper sub‐surface fracturesIce shell conducting layer depth is constrained to be less than 150 km [ABSTRACT FROM AUTHOR]

Heterogeneous light‐driven catalysis is a cornerstone of sustainable energy conversion. Most catalytic studies focus on bulk analyses of the hydrogen and oxygen evolved, which impede the correlation of matrix heterogeneities, molecular features, and bulk reactivity. Here, we report studies of a heterogenized catalyst/photosensitizer system using a polyoxometalate water oxidation catalyst and a model, molecular photosensitizer that were co‐immobilized within a nanoporous block copolymer membrane. Via operando scanning electrochemical microscopy (SECM), light‐induced oxygen evolution was determined using sodium peroxodisulfate (Na2S2O8) as sacrificial electron acceptor. Ex situ element analyses provided spatially resolved information on the local concentration and distribution of the molecular components. Infrared attenuated total reflection (IR‐ATR) studies of the modified membranes showed no degradation of the water oxidation catalyst under the reported light‐driven conditions. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The loop‐mediated isothermal amplification (LAMP) method is one of the Nucleic acid amplification tests (NAATs) that allows for the amplification of target regions without using a thermal cycle. With its unique primer design, LAMP ensures the rapid replication of the targeted DNA region with high specificity and high efficiency. LAMP technology is used for diagnostic purposes in pathogen detection due to its ease of use, low cost, and simplicity without requiring complex equipment. A wide range of LAMP diagnostic platforms have been developed for applications in bacteria, virus, and parasitic pathogen detection. Herein, the methodology of LAMP technology and its applications in pathogen detection and SNP genotyping and mutation detection are discussed. Point‐of‐care (PoC) LAMP platforms designed with the principles of microfluidic chip technology, including LAMP‐on‐a‐chip, paper‐based LAMP, and smartphone‐based LAMP applications have been elaborated. LAMP technology represents a fast, robust, and reliable diagnostic platform for point‐of‐care testing. [ABSTRACT FROM AUTHOR]

Correct photoluminescence quantum yield (PLQY) determination in the solid state is vital for numerous application fields, such as photovoltaics, solid lighting or the development of phosphors. In order to increase the limited number of suitable standards for such determinations, two new Ln3+‐based complexes with 4′‐phenyl‐2,2′ : 6′,2"‐terpyridine γ‐[Ln4(OAc)12(ptpy)2] (1‐Eu with europium and 1‐Tb with terbium) are presented. The corresponding complexes show solid‐state QYs of 58(4) % and 46(3) %, respectively, exhibiting broadband absorption in the UV range from 380–200 nm. As Ln3+ ions in general exhibit narrow f‐f transitions, spectral regions with a broadness of 20–35 nm can be checked. Both complexes have suitable thermal stability, up to 270 °C, and are stable with respect to air and humidity, for 1‐Eu up to 75 % and for 1‐Tb up to 53 % relative humidity. These complexes are altogether suitable as standards to increase the reliability of PLQY determination and proposed to be used for a relative PLQY determination in the solid state. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Difluoroboron β‐diketonate (BF2bdk) compounds represent an important class of luminescent materials, whereas their synthesis requires multiple steps, which restrict their application in diverse fields. Here we report a cascade reaction to prepare BF2bdk from aromatic ketones, carboxylic acids, trifluoroacetic anhydride and boron trifluoride diethyl etherate. The cascade reaction is very simple and straightforward to produce BF2bdk with desired functional groups in reasonable isolation yields. Further, when some specific BF2bdk compounds are used as luminescent dopants, organic room‐temperature phosphorescence with lifetimes >1.0 s and intense afterglow under ambient conditions can be achieved with the assistance by suitable organic matrices. The dopant‐matrix materials exhibit excellent processability into desired patterns and large‐area panels, and function as efficient donors of excited state energy transfer for the fabrication of red afterglow materials. The materials can be processed into aqueous afterglow dispersion that displays unique property of escaping the interference from strong fluorescence background. [ABSTRACT FROM AUTHOR]

With the popularization of modern computer technology, human society has stepped into the information age. Modern computer technology will have an all-round and deep impact on fine art education in China. In fine art education, various information devices play an important role in broadening the resources of fine art education and effectively improving the quality of fine art education. This study analyzes fine art education in the digital era and studies how the quality of fine art education can be improved through computer-aided technology. [ABSTRACT FROM AUTHOR]

Dual emission light‐emitting dendrimers composed of phosphorescent fac‐tris[2‐phenylpyridyl]iridium(III) [Ir(ppy)3] cores and thermally activated delayed fluorescence‐based (TADF‐based) dendrons have been prepared. The TADF‐based dendrons are designed to have green or blue emission. The dendrimers show solvatochromism, with the emission switching between phosphorescence and TADF depending on the medium in which the measurement is undertaken. Time‐dependent photoluminescence (PL) spectra measurements show that the TADF dendrons can act as an energy pool for emission from the phosphorescent core. The PL quantum yields (PLQYs) are found to be strongly dependent on the dielectric constant of the solvent, ranging from as high as 76% to as low as 0.3%. Neat films of the dendrimers are found to have relatively balanced hole and electron mobilities of order 10–6 cm2 V–1 s–1, with bilayer organic light‐emitting diodes (OLEDs) containing neat emissive layers having a maximum external quantum efficiency (EQE) of 4.7% for a film having a PLQY of 12%. Finally, the solution processed OLEDs fabricated using 0.4 mol% of the dendrimers blended with 9‐[3‐(9H‐carbazol‐9‐yl)phenyl]‐9H‐carbazole‐3‐carbonitrile result in green emission with maximum EQEs of 9.8% and 15.1% for the dendrimers with green and blue emissive TADF dendrons, respectively. [ABSTRACT FROM AUTHOR]

Fluorescence lifetime imaging (FLIM) allows the quantification of sub‐cellular processes in situ, in living cells. A number of approaches have been developed to extract the lifetime from time‐domain FLIM data, but they are often limited in terms of speed, photon efficiency, precision or the dynamic range of lifetimes they can measure. Here, we focus on one of the best performing methods in the field, the centre‐of‐mass method (CMM), that conveys advantages in terms of speed and photon efficiency over others. In this paper, however, we identify a loss of photon efficiency of CMM for short lifetimes when background noise is present. We subsequently present a new development and generalization of CMM that provides for the rapid and accurate extraction of fluorescence lifetime over a large lifetime dynamic range. We provide software tools to simulate, validate and analyse FLIM data sets and compare the performance of our approach against the standard CMM and the commonly employed least‐square minimization (LSM) methods. Our method features a better photon efficiency than standard CMM and LSM and is robust in the presence of background noise. The algorithm is applicable to any time‐domain FLIM data set. [ABSTRACT FROM AUTHOR]

We report the structure analysis, optical property, and catalytic implications of homoleptic alkynyl‐protected Au(I)‐Ag(I) nanocluster, namely Au9Ag9(C≡CArF)18 (abbreviated as Au9 Ag9 hereafter). Single crystal X‐ray diffraction analysis disclosed that, the core of Au9Ag9 cluster features intriguing ichthyomorphic assembled structure driven by metallophilic interactions and Au‐acetylide linkages. The Au9Ag9 nanocluster is fluorescent in both solution and solid state, and it has much higher quantum yield in solid state. In the electrochemical hydrogen evolution reaction (HER) test, Au9Ag9 nanocluster exhibits a favorable overpotential of 274 mV at 10 mA cm−2 with a Tafel slope of 99 mV dec−1, which markedly surpass than the [Au(C≡C‐ArF)]f and [Ag(C≡C‐ArF)]f control samples. Furthermore, Au9Ag9 nanocluster shows much higher activity than the other two to catalyze the reduction of 4‐nitrophenol. [ABSTRACT FROM AUTHOR]

Expanded graphite (EG) particles were introduced into the polyimide (PI) and polyethersulfone (PES) blend to enhance the dynamic thermomechanical and tribological performances of this polymer composite at evaluated temperatures ranging from room temperature to 250°C. The influences of EG dosage, evaluated temperature and vertical loads on the high‐temperature tribological behaviors, worn surface morphologies and wear mechanisms of EG/PES/PI composites were analyzed. Experimental results suggest that tensile strength, dynamic storage modulus, glass transition temperature as well as thermal stability of EG/PES/PI composites are superior to those of the PES/PI blend and they are raised as the EG additions increase. Whether at room temperature or at the high temperature of 250°C, the EG/PES/PI composites display the better friction‐reducing and abrasion resistant performances than the PES/PI blend. Among all these composites, the 7.0 wt% EG/PES/PI composite demonstrates the best friction and wear properties (0.23, 5.68 × 10−16 m3/[N·m]) at evaluated temperatures. The noticeable improvement in abrasive property of EG/PES/PI composites at high‐evaluated temperatures stems from extraordinary porous microstructures and outstanding lubrication characteristics of EG particles as well as the formation of uniform self‐lubricating polymer tribofilms. This composite as antifriction and wear‐resistant materials possesses potential applications in high‐temperature engineering tribology, such as rolling bearing retainer, and so forth. [ABSTRACT FROM AUTHOR]

Two challenges remain for organic thermoresponsive materials; one is to develop high‐performance red‐emissive thermoresponsive materials, while another is to simultaneously achieve high contrast ratio (CR), fast and reversible thermoresponse in a single element. Herein, we not only develop a new deep‐red emissive squaraine‐based AIEgen (TPE‐SQ12) based on a pyrylium end group, which is suitable for fabricating high‐performance thermoresponsive materials, but also show an effective approach to improve both CR (∼ten times increase) and response time (less than 3 seconds), that is, molecularly dispersing AIEgen into an elastomer, attributed to the significantly expanded free volume of elastomer upon increasing the temperature that can activate the AIEgen intramolecular movements more pronouncedly. Double encryption and temperature mapping systems have been separately established by using our designed elastomer/TPE‐SQ12 film, showing the great potential for anti‐counterfeiting and temperature sensing. Finally, white emission is further achieved by co‐doping TPE‐SQ12 with cyan dye into elastomer, which enables fluorescent thermochromism for improving the temperature mapping ability. [ABSTRACT FROM AUTHOR]

The high natural abundance of aluminium makes the respective fluorophores attractive for various optical applications, but photoluminescence quantum yields above 0.7 have yet not been reported for solutions of aluminium complexes. In this contribution, a dinuclear aluminium(III) complex featuring enhanced photoluminescence properties is described. Its facile one‐pot synthesis originates from a readily available precursor and trimethyl aluminium. In solution, the complex exhibits an unprecedented photoluminescence quantum yield near unity (Φabsolute 1.0±0.1) and an excited‐state lifetime of 2.3 ns. In the solid state, J‐aggregation and aggregation‐caused quenching are noted, but still quantum yields of 0.6 are observed. Embedding the complex in electrospun non‐woven fabrics yields a highly fluorescent fleece possessing a quantum yield of 0.9±0.04. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Myelination allows for the regulation of conduction velocity, affecting the precise timing of neuronal inputs important for the development and function of brain circuits. In turn, myelination may be altered by changes in experience, neuronal activity, and vesicular release, but the links between sensory experience, corresponding neuronal activity, and resulting alterations in myelination require further investigation. We thus studied the development of myelination in the Xenopus laevis tadpole, a classic model for studies of visual system development and function because it is translucent and visually responsive throughout the formation of its retinotectal system. We begin with a systematic characterization of the timecourse of early myelin ensheathment in the Xenopus retinotectal system using immunohistochemistry of myelin basic protein (MBP) along with third harmonic generation (THG) microscopy, a label‐free structural imaging technique. Based on the mid‐larval developmental progression of MBP expression in Xenopus, we identified an appropriate developmental window in which to assess the effects of early temporally patterned visual experience on myelin ensheathment. We used calcium imaging of axon terminals in vivo to characterize the responses of retinal ganglion cells over a range of stroboscopic stimulation frequencies. Strobe frequencies that reliably elicited robust versus dampened calcium responses were then presented to animals for 7 d, and differences in the amount of early myelin ensheathment at the optic chiasm were subsequently quantified. This study provides evidence that it is not just the presence but also to the specific temporal properties of sensory stimuli that are important for myelin plasticity. [ABSTRACT FROM AUTHOR]

Since 2014, we have introduced in literature the use of phenylglyoxylic acid (PhCOCOOH), a small and commercially available organic molecule, as a potent promoter in a variety of photochemical processes. Although PhCOCOOH has a broad scope of photochemical reactions that can promote, the understanding of its mode of action in our early contributions was moderate. Herein, we are restudying and revisiting the mechanism of action of PhCOCOOH in most of these early contributions, providing a unified mechanism of action. Furthermore, the understanding of its action as a photoinitiator opened a new comparison study with known and commercially available photoinitiators. [ABSTRACT FROM AUTHOR]

Germinal centers (GCs) are the site of antibody affinity maturation, a fundamental immunological process that increases the potency of antibodies and thereby their ability to protect against infection. GC biology is highly dynamic in both time and space, making it ideally suited for intravital imaging. Using multiphoton laser scanning microscopy (MPLSM), the field has gained insight into the molecular, cellular, and structural changes and movements that coordinate affinity maturation in real time in their native environment. On the other hand, several limitations of MPLSM have had to be overcome to allow full appreciation of GC events taking place across different timescales. Here, we review the technical advances afforded by intravital imaging and their contributions to our understanding of GC biology. [ABSTRACT FROM AUTHOR]

Light at night in adults suppresses melatonin in a nonlinear intensity‐dependent manner. In children, bright light of a single intensity before bedtime has a robust melatonin suppressing effect. To our knowledge, whether evening light of different intensities is related to melatonin suppression in young children is unknown. Healthy, good‐sleeping children (n = 36; 3.0–4.9 years; 39% male) maintained a stable sleep schedule for 7 days followed by a 29.5‐h in‐home dim‐light circadian assessment (~1.5 lux). On the final night of the protocol, children received a 1‐h light exposure (randomized to one of 15 light levels, ranging 5–5000 lux, with ≥2 participants assigned to each light level) in the hour before habitual bedtime. Salivary melatonin was measured to calculate the magnitude of melatonin suppression during light exposure compared with baseline levels from the previous evening, as well as the degree of melatonin recovery 50 min after the end of light exposure. Melatonin levels were suppressed between 69.4% and 98.7% (M = 85.4 ± 7.2%) during light exposure across the full range of intensities examined. Overall, we did not observe a light intensity‐dependent melatonin suppression response; however, children exposed to the lowest quartile of light intensities (5–40 lux) had an average melatonin suppression (77.5 ± 7.0%) which was significantly lower than that observed at each of the three higher quartiles of light intensities (86.4 ± 5.6%, 89.2 ± 6.3%, and 87.1 ± 5.0%, respectively). We further found that melatonin levels remained below 50% baseline for at least 50 min after the end of light exposure for the majority (62%) of participants, and recovery was not influenced by light intensity. These findings indicate that preschool‐aged children are highly sensitive to light exposure in the hour before bedtime and suggest the lighting environment may play a crucial role in the development and the maintenance of behavioral sleep problems through impacts on the circadian timing system. [ABSTRACT FROM AUTHOR]

Neurons can change their classical neurotransmitters during ontogeny, sometimes going through stages of dual release. Here, we explored the development of the neurotransmitter identity of neurons of the avian nucleus isthmi parvocellularis (Ipc), whose axon terminals are retinotopically arranged in the optic tectum (TeO) and exert a focal gating effect upon the ascending transmission of retinal inputs. Although cholinergic and glutamatergic markers are both found in Ipc neurons and terminals of adult pigeons and chicks, the mRNA expression of the vesicular acetylcholine transporter, VAChT, is weak or absent. To explore how the Ipc neurotransmitter identity is established during ontogeny, we analyzed the expression of mRNAs coding for cholinergic (ChAT, VAChT, and CHT) and glutamatergic (VGluT2 and VGluT3) markers in chick embryos at different developmental stages. We found that between E12 and E18, Ipc neurons expressed all cholinergic mRNAs and also VGluT2 mRNA; however, from E16 through posthatch stages, VAChT mRNA expression was specifically diminished. Our ex vivo deposits of tracer crystals and intracellular filling experiments revealed that Ipc axons exhibit a mature paintbrush morphology late in development, experiencing marked morphological transformations during the period of presumptive dual vesicular transmitter release. Additionally, although ChAT protein immunoassays increasingly label the growing Ipc axon, this labeling was consistently restricted to sparse portions of the terminal branches. Combined, these results suggest that the synthesis of glutamate and acetylcholine, and their vesicular release, is complexly linked to the developmental processes of branching, growing and remodeling of these unique axons. [ABSTRACT FROM AUTHOR]

A simple, selective and sensitive "signal-on" electrogenerated chemiluminescence (ECL) biosensing method was developed for matrix metalloproteinase 2 (MMP-2). Ru(bpy)32+, gold nanoparticles (AuNPs) and Nafion were modified onto glassy carbon electrode (GCE) to form Ru(bpy)32+/AuNPs/Nafion/GCE as sensitive ECL platform and then ferrocene (Fc) labeled peptide was assembled onto the modified electrode to form ECL biosensing platform. The ECL intensity increased when the ECL biosensing electrode reacted with MMP-2 because of MMP-2-induced cleavage of Fc labeled peptide. The ECL method was applied to determine MMP-2 with detection limit of 0.3 ng/mL and one-step recognition, which is promising for point-of-care test of protease. [ABSTRACT FROM AUTHOR]

Key points: M1 intrinsically photosensitive retinal ganglion cells (ipRGCs) are known to encode absolute light intensity (irradiance) for non‐image‐forming visual functions (subconscious vision), such as circadian photoentrainment and the pupillary light reflex.It remains unclear how M1 cells respond to relative light intensity (contrast) and patterned visual signals.The present study identified a special form of contrast sensitivity (suppressed‐by‐contrast) in M1 cells, suggesting a role of patterned visual signals in regulating non‐image‐forming vision and a potential role of M1 ipRGCs in encoding image‐forming visual cues.The study also uncovered a synaptic mechanism and a retinal circuit mediated by vesicular glutamate transporter 3 (vGluT3) amacrine cells that underlie the suppressed‐by‐contrast response of M1 cells.M1 ipRGC subtypes (M1a and M1b) were revealed that are distinguishable based on synaptic connectivity with vGluT3 amacrine cells, receptive field properties, intrinsic photo sensitivity and membrane excitability, and morphological features, suggesting a division of visual tasks among discrete M1 subpopulations. The M1 type ipRGC (intrinsically photosensitive retinal ganglion cell) is known to encode ambient light signals for non‐image‐forming visual functions such as circadian photo‐entrainment and the pupillary light reflex. Here, we report that a subpopulation of M1 cells (M1a) in the mouse retina possess the suppressed‐by‐contrast (sbc) trigger feature that is a receptive field property previously found only in ganglion cells mediating image‐forming vision. Using optogenetics and the dual patch clamp technique, we found that vesicular glutamate transporter 3 (vGluT3) (vGluT3) amacrine cells make glycinergic, but not glutamatergic, synapses specifically onto M1a cells. The spatiotemporal and pharmacological properties of visually evoked responses of M1a cells closely matched the receptive field characteristics of vGluT3 cells, suggesting a major role of the vGluT3 amacrine cell input in shaping the sbc trigger feature of M1a cells. We found that the other subpopulation of M1 cells (M1b), which did not receive a direct vGluT3 cell input, lacked the sbc trigger feature, being distinctively different from M1a cells in intrinsic photo responses, membrane excitability, receptive‐field characteristics and morphological features. Together, the results reveal a retinal circuit that uses the sbc trigger feature to regulate irradiance coding and potentially send image‐forming cues to non‐image‐forming visual centres in the brain. [ABSTRACT FROM AUTHOR]

A new platinum(II) porphyrin complex has been synthesized and characterized via various spectroscopic techniques. Single‐crystal XRD analysis reveals that the geometry around the Pt(II) center is near the perfect square planar geometry. The Pt(II)−N bond distances are in the ranges of 2.005 Å–2.020 Å. The platinum(II) porphyrin derivative exhibited one reversible oxidative couple at +1.10 V and a reversible reductive couple at −1.47 V versus Ag/AgCl. In deaerated dichloromethane solution at 298 K, a strong phosphorescence is observed at 660 nm, with emission quantum yield of 35 % and lifetime of 75 μs. Upon excitation of the acenaphthene chromophores at 300 nm, sensitised phosphorescence of the Pt(II) porphyrin is observed with a unitary efficient energy transfer, demonstrating that this system behaves as a light harvesting antenna. The red phosphorescence is strongly quenched by oxygen, resulting in singlet oxygen production with a very high quantum yield of 88 %. This result indicates that this Pt(II) porphyrin is an excellent photosensitizer for the production of singlet oxygen and will have potential applications in the field of photodynamic therapy as well as oxygen sensors. [ABSTRACT FROM AUTHOR]

The salts {[Ln2Ln*(Hhmq)3(OAc)3(hfac)2]+ [Ln*(hfac)3(OAc)(MeOH)]−} (Hhmq=2‐methanolquinolin‐8‐oxide, hfac=hexafluoroacetylacetonate; Ln, Ln*=Er, Gd, Yb) feature a discrete heteronuclear cation consisting of two types of lanthanide atoms. The quinolinoxy O‐atom serves as a μ2‐bridge to two Ln atoms and as a μ3‐bridge to all three atoms, with metal⋅⋅⋅metal distances being around 3.7 Å. For 1 ([Yb2Er]+), near‐infrared downshifted luminescence is switched to competitive upconversion luminescence upon irradiation by a 980 nm laser under an extremely low excitation power (0.288 W cm−2) through introduction of fluoride ions. The stability of 1 after addition of fluoride was confirmed by powder X‐ray diffraction and multistage mass spectrometry, associated with the 1H NMR of 6 ([La2Eu]+). More importantly, the at least 20‐fold enhancement of the quantum yield in non‐deuterated solvents at room temperature under low power densities (2 W cm−2) is the highest among the few molecular examples reported. [ABSTRACT FROM AUTHOR]

Evaluating the efficiency of newly designed photoreactors is crucial for systematic development and optimization of photochemical processes. A suitable tool is actinometry, prominently represented by the most widely studied and applied ferrioxalate system. However, such measurements show reproducibility problems in the data consistency. This study scrutinizes these issues and approaches an experimental elucidation. An application limit for the ferrioxalate actinometer under intense irradiation was identified and experimentally validated. A drop of the quantum yield at high incident photon fluxes, generating high local concentrations of carboxyl radicals, leads to systematically wrong measurements. For reliable measurements with the ferrioxalate actinometry, a continuous operation mode or extensive mixing should be ensured. [ABSTRACT FROM AUTHOR]

The brain possesses structural and functional hierarchical architectures organized over multiple scales. Considering that functional recordings commonly focused on a single spatial level, and because multiple scales interact with one another, we explored the behaviour of in silico neuronal networks across different scales. We established ad hoc relations of several topological descriptors (average clustering coefficient, average path length, small‐world propensity, modularity, network degree, synchronizability and fraction of long‐term connections) between different scales upon application and empirical validation of a Euclidian renormalization approach. We tested a simple network (distance‐dependent model) as well as an artificial cortical network (Vertex; undirected and directed networks) finding the same qualitative power law relations of the parameters across levels: their quantitative nature is model dependent. Those findings were then organized in a workflow that can be used to predict, with approximation, microscale topologies from mesoscale recordings. The present manuscript not only presents a theoretical framework for the renormalization of biological neuronal network and their study across scales in light of the spatial features of the recording method but also proposes an applicable workflow to compare real functional networks across scales. [ABSTRACT FROM AUTHOR]

Actinometers are physical or chemical systems that can be employed to determine photon fluxes. Chemical actinometers are photochemical systems with known quantum yields that can be employed to determine accurate photon fluxes for specific photochemical reactions. This review explores in detail several practical chemical actinometers (ferrioxalate, iodide–iodate, uranyl oxalate, nitrate, uridine, hydrogen peroxide and several actinometers for the vacuum ultraviolet). Each actinometer is described with recommended conditions for its use. [ABSTRACT FROM AUTHOR]

The sensory cortex underlies our ability to perceive and interact with the external world. Sensory perceptions are controlled by specialized neuronal circuits established through fine‐tuning, which relies largely on neuronal activity during the development. Spontaneous neuronal activity is an essential driving force of neuronal circuit refinement. At early developmental stages, sensory cortices display spontaneous activities originating from the periphery and characterized by correlated firing arranged spatially according to the modality. The firing patterns are reorganized over time and become sparse, which is typical for the mature brain. This review focuses mainly on rodent sensory cortices. First, the features of the spontaneous activities during early postnatal stages are described. Then, the developmental changes in the spatial organization of the spontaneous activities and the transition mechanisms involved are discussed. The identification of the principles controlling the spatial organization of spontaneous activities in the developing sensory cortex is essential to understand the self‐organization process of neuronal circuits. This review aims to provide an integrated overview of the spatial organization of the neuronal spontaneous activity in sensory cortices with a focus on recent studies. [ABSTRACT FROM AUTHOR]

Three new aza‐BODIPY dyes incorporating fused fluorene or carbazole moieties have been prepared. The dyes show significant enhancement of photophysical properties compared to the parent 1,3,5,7‐tetraphenyl aza‐BODIPY (TPAB): a bathochromic shift of the absorption maximum (up to 2700 cm−1) and emission maximum (up to 2270 cm−1); an almost threefold increase in molar absorption coefficients (to ca. 230 000 M−1 cm−1) and a significant increase in the fluorescence quantum yield to 49–66 %. Owing to the combination of these properties, the new aza‐BODIPY dyes belong to the brightest NIR dyes reported. The dyes also show excellent photostability. Due to their outstanding properties, the new dyes represent a promising platform for further exploration in biomedical research. A pH indicator containing only one fused carbazole unit was also prepared and shows absorption and emission spectra that are bathochromically shifted by about 110 and 100 nm, respectively, compared to the indicator dye based on the TPAB chromophore. [ABSTRACT FROM AUTHOR]