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The design and synthesis of chiral covalent organic frameworks (COFs) with controlled defect sites are highly desirable but still remain largely unexplored. Herein, we report the synthesis of a defective chiral HD‐TAPB‐DMTP COF by modifying the chiral monomer helicid (HD) into the framework of an achiral imine‐linked TAPB‐DMTP COF using a chiral monomer exchange strategy. Upon the introduction of the chiral HD unit, the obtained defective chiral HD‐TAPB‐DMTP COF not only displays excellent crystallinity, large specific surface area (up to 2338 m2/g) and rich accessible chiral functional sites but also exhibits fluorescence emission, rendering it a good candidate for discrimination of amino acids. Notably, the resultant defective chiral HD‐TAPB‐DMTP COF can be used as a fluorescent sensor for enantioselective recognition of both tyrosine and phenylalanine enantiomers in water, showing enhanced fluorescent responses for the L conformations over those of the D conformations with the enantioselectivity factors being 1.84 and 2.02, respectively. Moreover, molecular docking simulations uncover that stronger binding affinities between chiral HD‐TAPB‐DMTP COF and L‐tyrosine/L‐phenylalanine in comparison to those with D‐tyrosine/D‐phenylalanine play important roles in enantioselective determination. This work provides new insights into the design and construction of highly porous defective chiral COFs for enantioselective fluorescence recognition of amino acids. [ABSTRACT FROM AUTHOR]

Fluorescence-based chemical sensors have garnered significant attention due to their rapid response, high sensitivity, cost-effectiveness and ease of operation. Recently, metal–organic frameworks (MOFs) have been extensively utilized as platforms for constructing fluorescence sensors, owing to their ultra-high porosity, flexible tunability, and excellent luminescent properties. This feature article summarizes the progress made mainly by our research group in recent years in the construction strategies, principles, and types of MOF sensors, as well as their applications in quantitative sensing, qualitative identification analysis, and multimodal/multifunctional analysis. In addition, the challenges and an outlook on the future progression of MOF-based sensors are discussed, highlighting how these studies can contribute to addressing these issues. Hopefully, this feature article can provide some valuable guidance for the construction and application of MOFs in fluorescence sensing, thereby broadening their practical applications. [ABSTRACT FROM AUTHOR]

The convergence of advanced nanotechnology with disease diagnosis has ushered in a transformative era in healthcare, empowering early and accurate detection of diseases and paving the way for timely interventions, improved treatment outcomes, and enhanced patient well‐being. The development of novel materials is frequently the impetus behind significant advancements in sensor technology. Among them, single‐walled carbon nanotubes (SWCNTSs) have emerged as promising nanomaterials for developing biosensors. Their unique optical, electrical, and biocompatibility properties make them promising candidates for enhancing the sensitivity and real‐time monitoring capabilities of biosensors, as well as for enabling various bioimaging techniques. Recent studies have demonstrated the utility of SWCNTS‐based biosensors in the real‐time monitoring of biological analytes, such as nitric oxide and hydrogen peroxide (H2O2), with potential implications for disease understanding and therapeutic response assessment. Moreover, SWCNTSs have shown promise in bioimaging applications, including fluorescence, Raman spectroscopy, and photoluminescence imaging of biological samples. This article delves into the core principles, design strategies, and operational mechanisms that underpin SWCNTS‐bioimaging techniques‐based biosensors. It emphasizes on their unique properties and versatile functionalization of carbon nanotubes, laying the foundation for their integration into biosensor platforms and applications aimed at diagnosing a wide spectrum of diseases including infectious diseases, cancer, neurological disorders, and metabolic conditions. [ABSTRACT FROM AUTHOR]

Fluorogens with aggregation‐induced emission (AIEgens) are promising agents for two‐photon fluorescence (TPF) imaging. However, AIEgens' photophysical properties are fixed and unoptimizable once synthesized. Therefore, it is urgent and meaningful to explore an efficient post‐regulation strategy to optimize AIEgens' photophysical properties. Herein, a general and efficient post‐regulation strategy is reported. By simply tuning the ratio of inert AIEgens within binary nanoparticles (BNPs), the fluorescence quantum yield and two‐photon absorption cross‐section of functional AIEgens are enhanced by 8.7 and 5.4 times respectively, which are not achievable by conventional strategies, and the notorious phototoxicity is almost eliminated. The experimental results, theoretical simulation, and mechanism analysis demonstrated its feasibility and generality. The BNPs enabled deep cerebrovascular network imaging with ≈1.10 mm depth and metastatic cancer cell detection with single‐cell resolution. Furthermore, the TPF imaging quality is improved by the self‐supervised denoising algorithm. The proposed binary molecular post‐regulation strategy opened a new avenue to efficiently boost the AIEgens' photophysical properties and consequently TPF imaging quality. [ABSTRACT FROM AUTHOR]

Bis(8‐hydroxyquinolates) Zinc (Znq2) can be used as a light‐emitting layer material in OLED devices to achieve its efficient electroluminescence effect. In this paper, Znq2 powder has been successfully synthesized and modified by the physical vapor deposition (PVD) method. Precursors and nano‐materials are characterized by XRD, SEM, PL, and so on. The performance of the modified material has been significantly improved. The emission intensity and absorption intensity in the deposited products increased with the increase in PVD temperature. At 453 K, luminous properties such as luminous intensity reach the optimal value including its fluorescence lifetime. Fluorescence lifetime values vary from 13 to 17 ns with the increase in temperature. The luminescence mechanism is also discussed. The energy gap and absorption spectrum of HOM‐LUMO are calculated by the DFT/UB3LYP method. The experimental values agree well with the theoretical values. The nanomaterial crystals modified by PVD technology are more orderly, impurities are reduced, and the luminous stability of the material is improved, which may be one of the reasons for the relatively slow decline in product life. The research combined with theoretical simulation is expected to be helpful to the research and promotion of such materials. [ABSTRACT FROM AUTHOR]

The issue of counterfeiting has always been a major challenge in today's society, putting forward high requirements for anti‐counterfeiting technology. Here, a promising 2D/3D anti‐counterfeiting security system is developed based on anthracene‐functionalized poly(styrene‐butadiene‐styrene) (SBS‐CAN), which possessed the physical unclonable self‐wrinkling patterns, fluorescence, and shape memory behavior. By controlling the dimerization of anthracene groups with ultraviolet light and external pre‐stretched operation, 2D information with surface wrinkle and fluorescence is achieved, allowing for the design of security systems based on actual needs. Furthermore, 3D structures constructed based on the shape memory behavior can further be utilized to encrypt these 2D information, enhancing the security level and weakening the cloneable risk of surface wrinkle and fluorescence for further. This programmable 2D/3D anti‐counterfeiting system has multiple advantages over the commonly used fluorescent wrinkled tag or fluorescent shape memory label, providing an intelligent choice for high‐security information carriers. [ABSTRACT FROM AUTHOR]

The porous Ti/perovskite composites were prepared successfully by ultrasound-assisted infiltration method. The Cs–Pb–Br perovskite materials were prepared on a larger scale by the mechanical ball-milling using the CsBr and PbBr 2 as the precursors. The Cs–Pb–Br perovskites had high PL intensity and excellent stability, meanwhile, the complex phase transformation between CsPbBr 3 and Cs 4 PbBr 6 occurred during the ball-milling process. The green fluorescence emission of composites might be attributed to CsPbBr 3 embedded within Cs 4 PbBr 6 perovskite. By the space occupying method, the porous Ti materials were prepared by using the acicular urea as the pore forming. The optimal young's modulus (1.0851 GPa) and porosity (38.27 %) were obtained. Finally, the prepared Ti/perovskite composites had outstanding fluorescence property and high stability, showing the wide application prospect in the fields of the bioflourescence imaging and nondestructive testing fields. [ABSTRACT FROM AUTHOR]

Fluorescence intensity ratio (FIR) thermometers have obtained great attention in industrial production, medical diagnosis and scientific research. However, the sensitivity has a large decline at high temperatures, which seriously limits the practical applications. Here, the Yb,Er,Tm:Sc 2 O 3 single crystal fibers were grown by laser-heated pedestal growth (LHPG) technique and its multi-mode FIR thermometry based on thermal coupled energy levels (TCLs) and non-thermal coupled energy levels (NTCLs) has been well demonstrated. The temperature measuring range of Yb,Er,Tm:Sc 2 O 3 single crystal fibers covers 298–973 K, with an increase of 2 orders of magnitude in absolute sensitivity. The relative sensitivity is higher than 0.02 % K−1 in the whole T-range of 298∼973 K, with a maximum value of 1.02 % K−1. Especially at the high temperatures of 973 K, it can still maintain 0.31 % K−1. This work proposes an innovative fluorescence intensity ratio detection strategy to achieve complementary disadvantages between TCLs and NTCLs and provides an effective method for improving detection sensitivity. [ABSTRACT FROM AUTHOR]

Marine aggregates, composed of various particles, play a crucial role in ocean carbon storage. The overall size distribution of the aggregates (number size spectra) is controlled by the balance between aggregation and disaggregation processes. Turbulence has been proposed to facilitate both aggregation and disaggregation by increasing the collision rate of aggregates or sometimes directly tearing them apart. Predominant processes driven by turbulence typically depend on the level of turbulence—relatively weak turbulence is associated with aggregation while stronger turbulence promotes disaggregation. Aggregate strength also plays a key role, as strongly bonded aggregates can withstand turbulence better, leading to lower disaggregation rates. While the relationship between turbulence and aggregate strength has been studied numerically and experimentally, field measurements remain limited. Here, we compare our number size spectra to turbulence intensity from the field measurements across different environmental settings around Japan to determine the effect of turbulence on aggregate strength. We combined measurements from 10 sites with different environmental settings and observed the flatter slopes (higher net aggregation rate) and shifts in the intersection lengths with an increase of turbulence, while strong turbulence is typically linked with disaggregation. Our findings suggested that stronger aggregates are formed under stronger turbulence and the overall population of strong aggregates also increases with an increase of turbulence intensity. We also compared our number size spectra with three other confounding factors (fluorescence, salinity, and aggregate compositions) to confirm the effects of turbulence are dominant in our aggregate dynamics. [ABSTRACT FROM AUTHOR]

Synthesis of a series of indolo[1,2‐a]quinoxaline derivatives substituted with phthalazinones/isoindolinones/carbonyl benzoylesters at C‐4 position have been accomplished under open air rt/heating conditions following ANRORC (Addition of Nucleophile, Ring Opening and Ring Closure) mechanism. Initially condensation of 2‐(1‐indolyl)‐aniline and ninhydrin generates a spirocyclic intermediate 5′H‐spiro[indene‐2,6′‐indolo[1,2‐a]quinoxaline]‐1,3‐dione, which upon reaction with various nucleophiles like hydrazine/phenylhydrazine, amines and alcohols affords C‐4 substituted indolo[1,2‐a]quinoxalines in high yield (up to ~88 %) via ANRORC. The photophysical investigation shows that the quinoxaline derivatives possess significant fluorescence property with high quantum yield (QY~11.0–17.0). The N‐phenylphthalazinone substituted indolo[1,2‐a]quinoxaline, a molecule structurally similar to 2,2′‐bipyridine system, can efficiently and selectively detect Fe2+ through fluorescence turn off sensing. [ABSTRACT FROM AUTHOR]

Supramolecular have promising application prospects owing to their catalytic, self‐healing, and stimulus‐responsive functions. Pyridylethynylimidazole‐based supramolecular synthons with fluorescent properties have been developed. 4‐(2‐Pyridylethynyl)‐5‐arylethynyl‐1H‐imidazole derivatives 1 with different substituents at the 4‐ and 5‐positions of the imidazole skeleton were prepared using a step‐by‐step Sonogashira coupling reaction. The fluorescence maxima of phenyl‐ and methoxyphenyl‐substituted derivatives 1a and 1c were independent of solvent polarity. On the other hand, ester‐ and cyano‐substituted 1b and 1d showed bathochromically shifted fluorescence maxima in highly polar solvents. In crystals, the 4‐(2‐pyridylethynyl)‐5‐arylethynyl‐1H‐imidazole derivatives formed a supramolecular cyclic tetramer structure via two hydrogen bonds: one was between N─H in imidazole and N in pyridine, and the other was between C─H in imidazole and N in imidazole. Introducing the pyridine ring as a hydrogen bond acceptor, in addition to the imidazole ring, promoted the unique cyclic tetramer structure formation. [ABSTRACT FROM AUTHOR]

Osteoarthritis is a prevalent chronic health condition that is mostly associated with the degeneration of joint cartilage due to aging or abnormal mechanical stress in the joint. Intraarticularly injected nanoparticle‐based lubricants decrease the friction between damaged cartilage surfaces, thus preventing their further degradation; however, the effectiveness of currently used nanoparticle‐based lubricants is limited by their short retention time in the joint space. To address this challenge, cationically modified biosourced phytoglycogen nanolubricants are utilized, which electrostatically bind to the cartilage components. The conjugation of the nanoparticles with red‐emissive fluorescent carbon dots enables in vivo studies of their retention in the joint. The hytoglycogen nanoconjugates exhibit high colloidal stability in physiological conditions, provide a friction coefficient of 10−3–10−2 between the sliding surfaces under physiologically relevant pressures, strongly bind to the major cartilage surface components, and show significantly prolonged retention time in the joint in vivo, with a fourfold increase in half‐life in comparison with conventionally used hyaluronic acid injectant. These properties make these functionalized phytoglycogen nanoparticles a highly promising candidate for joint lubrication. [ABSTRACT FROM AUTHOR]

A non‐destructive method for determining the color value of pelletized red peppers is crucial for pepper processing factories. This study aimed to investigate the potentiality of visible and fluorescence images for the determination of color value of pelletized red pepper. The imaging problem, caused by the cylindrical shape and irregular cross‐sectional features of the pelletized red peppers, was reduced through the extraction of an approximate plane region. To integrate the information in the visible and fluorescence images, a baseline convolutional neural network (CNN) architecture was designed and low level, middle level, and high level fusion models (denoted as LL‐CNN, ML‐CNN, and HL‐CNN, respectively) were developed upon the baseline CNN. The effects of input image size and color space were examined. According to the training result, CNN fusion models were developed using visible image in L*a*b* color space and fluorescence image in RGB color space using 56 × 56 input image size. Among the three types of CNN fusion models, the HL‐CNN obtained the best performance, resulting in Rv2 of 0.828 and RMSEV of 0.351. This study suggests that the fusion of visible and fluorescence image through CNN is a practical approach to save testing time and replace traditional destructive method. The low cost and compact structure of the imaging systems can maintain the commercial appeal of pepper industry. [ABSTRACT FROM AUTHOR]

Unlocking the afterglow properties of the fluorescence molecules at room temperature is an urgent challenge. Herein, inks prepared with dimethyl terephthalate (DTT) and carbazole (Cz) analogs with heteroatom (C, S, and O) substituents on the N as host and guest molecules can be directly sprayed onto different substrates to unlock the excitation‐wavelength dependent (Ex‐De) afterglow characteristics of the guest compound. Additionally, with the increase in the number of lone pair electrons, spin‐orbit coupling (SOC) increases, resulting in a longer afterglow duration lasting up to 4.5 s with Φp>27%. Theory calculations and experiments indicate that the afterglow originated from the interactions between the host and guest molecules restricting the non‐radiative transition of the triplet excitons. Different Ex (with watershed at 310 nm) lead to the variation in the conformation of the S0DTT and S1DTT, which in turn affects the strength of host‐guest interactions and contributes to the Ex‐De characteristics. Benefiting from facile preparation, substrate‐independent applicability, and Ex‐De characteristics, the afterglow samples are demonstrated for applications in multilevel information security fields. This work proposes a general strategy for unlocking the afterglow emission of traditional molecules, which is valuable for the discovery of high‐performance afterglow materials in the future. [ABSTRACT FROM AUTHOR]

Background: Innovative attempt to explore the feasibility and accuracy of using indocyanine green fluorescence (ICGF) to identify the intersegmental plane by the target segmental veins preferential ligation during thoracoscopic segmentectomy. Methods: A retrospective analysis was conducted on clinical data of 32 consecutive patients who underwent thoracoscopic segmentectomy with intersegmental plane identification using both ICGF and inflation-deflation method after target segmental veins prioritized blocking at Nanjing Chest Hospital from December 2022 to June 2023. Preoperative three-dimensional reconstruction was used to identify the target segment and the anatomical structure of the arteries, veins, and bronchi. After ligating the target segmental veins during surgery, the first intersegmental plane was immediately identified and marked with an electrocoagulation device using an inflation-deflation method. Subsequently, the second intersegmental plane was determined using the ICGF method. Finally, the consistency of the two intersegmental planes was evaluated. Results: All the 32 patients successfully completed thoracoscopic segmentectomy without ICG-related complications and perioperative death. The average operation time was (98.59 ± 20.72) min, the average intraoperative blood loss was (45.31 ± 35.65) ml, and the average postoperative chest tube removal time was (3.5 ± 1.16) days. The average postoperative hospital stay was (4.66 ± 1.29) days, and the average tumor margin width was (26.96 ± 5.86) mm. The intersegmental plane determined by ICGF method was basically consistent with inflation-deflation method in all patients. Conclusion: The ICGF can safely and accurately identify the intersegmental plane by target segmental veins preferential ligation during thoracoscopic segmentectomy, which is a beneficial exploration and important supplement to the simplified thoracoscopic anatomical segmentectomy. [ABSTRACT FROM AUTHOR]

The synthesis of substituted 3‐oxo‐pyrimido[1,2‐b]indazoles from 3‐aminoindazoles and ketones has been established. It involves one molecule of 3‐aminoindazoles and two molecules of ketones via a [3+2+1] three‐component annulation process. 3‐Oxo‐pyrimido[1,2‐b]indazoles exhibit strong yellow fluorescence in various solvents. A wide range of products have anti‐oxidant activities. Cytotoxicity studies indicate that compounds 3 a, 3 aa and 3 ab have obvious effects on both HCT116 and A549 cancer cell lines. [ABSTRACT FROM AUTHOR]

Many organic dyes are fluorescent in solution. In the solid state, however, quenching processes often dominate, hampering material science applications such as light filters, light‐emitting devices, or coding tags. We show that the dimethylene‐cyclopropanide scaffold can be used to form two structurally different types of chromophores, which feature fluorescence quantum yields up to 0.66 in dimethyl sulfoxide and 0.53 in solids. The increased fluorescence in the solid state for compounds bearing malonate substituents instead of dicyanomethide ones is rationalized by the induced twist between the planes of the cyclopropanide core and a pyridine ligand. [ABSTRACT FROM AUTHOR]

2-Hydroxypropyl-β-cyclodextrin (2-Hp-β-CD)-functionalized CdTe quantum dots (QDs) were used for coumarin-sensing with high sensitivity and selectivity. This fluorescence resonance energy transfer (FRET)-based sensor was established by attaching rhodamine 6G (Rh6G) to the QDs via a 2-Hp-β-CD linker. Rh6G could get into the cavity of 2-Hp-β-CD, and then trigger the FRET between the QDs and Rh6G, providing an "off" state of the QDs. However, the effect of FRET was weakened by the coumarin, because of its larger hydrophobic association constant with 2-Hp-β-CD, resulting in the dissociation of Rh6G. In the presence of additive coumarin, the fluorescence intensity of QDs@2-Hp-β-CD@Rh6G increases (an "on" state). The FRET-based off–on nanoprobe shows a good linear relationship in the range of 0–25 μM with a good correlation coefficient (R2 = 0.9986). We also obtained an excellent result using this spectrophotometric method for coumarin sensing in cosmetics, which has potential for application in the biomedical area. We expect this sensing platform could be useful in other analogous nanoprobes in relevant fields. [ABSTRACT FROM AUTHOR]

A new colorimetric and fluorescence turn‐on chemodosimeter for selective detection of GSH over Cys and Hcy with 34‐fold enhancement in emission intensity is reported. Probe 1 exhibited ultra‐sensitivity toward GSH with 0.125 nM detection limit and successfully displayed GSH detection in MCF‐7 live cells. The mechanism of sensing is established by density functional theoretical calculations. [ABSTRACT FROM AUTHOR]

Hemin is an important iron‐containing porphyrin that has important therapeutic properties to control the symptoms of porphyria attacks that include pain, high blood pressure, rapid heartbeat, mental changes, and so forth. Lysozyme has many applications, which include from therapeutic to preservation of foods. The interaction of hemin with an important model protein, hen egg white lysozyme (HEWL), has been observed in this study through hybrid in silico with biophysical studies. There was a strong 1:1 cooperative binding between hemin and HEWL, which was revealed from the strong quenching of the latter by the former. The binding was favored by the decrease in temperature, which is due to the involvement of static type of quenching mechanism in the interaction. Experimental analyses suggested that the major forces involved in the binding were polar ones, and there was an efficient energy transfer from the fluorophore to the ligand. The combination of far‐UV CD spectroscopy and Rayleigh light scattering experiments established that hemin has the strong tendency to unfold HEWL. An extensive molecular docking investigation involving 2000 docking runs recognized the preferred binding site of hemin within HEWL, and also suggested that apart from the polar forces, hydrophobic interactions have also played an important role in the binding. [ABSTRACT FROM AUTHOR]

Surgical resection remains the primary treatment modality for glioblastoma (GBM); however, the infiltrative nature of GBM margins complicates achieving complete tumor removal. Additionally, the blood-brain barrier (BBB) poses a formidable challenge to effective probe delivery, thereby hindering precise imaging-guided surgery. Here, we introduce hybrid cell membrane-coated indocyanine green (ICG) liposomes (HM-Lipo-ICG) as biomimetic near-infrared (NIR) fluorescent probes for targeted BBB penetration and accurate delineation of infiltrative GBM margins. HM-Lipo-ICG encapsulates clinically approved ICG within its core and utilizes a hybrid cell membrane exterior, enabling specific targeting and enhanced BBB permeation. Quantitative assessments demonstrate that HM-Lipo-ICG achieves BBB penetration efficiency 2.8 times higher than conventional ICG liposomes. Mechanistically, CD44 receptor-mediated endocytosis facilitates BBB translocation of HM-Lipo-ICG. Furthermore, HM-Lipo-ICG enables high-contrast NIR imaging, achieving a signal-to-background ratio of 6.5 in GBM regions of an orthotopic glioma mouse model, thereby improving tumor margin detection accuracy fourfold (84.4% vs. 22.7%) compared to conventional ICG liposomes. Application of HM-Lipo-ICG facilitates fluorescence-guided precision surgery, resulting in complete resection of GBM cells. This study underscores the potential of hybrid cell membrane-coated liposomal probes in precisely visualizing and treating infiltrative GBM margins. [ABSTRACT FROM AUTHOR]

The crucial point of solar thermal utilization makes solar heat collector gathering much attention. In this study, imitating polar bears' fur structure, fluorescent materials are modified into a solar heat collector, and the photothermal conversion is evaluated to examine the influence of polyvinyl alcohol concentration, fluorescent luminescence type and fluorescence concentration. The test results indicate that fluorescent materials that has a greater Stokes shift show the greater photothermal effect. Moreover, when composed of a PVA concentration being 5.0% and a fluorescent concentration being 0.50%, the composites exhibit the maximal photothermal conversion temperature (99.4°C) that is 17.9% higher than that of the solar heat collectors without fluorescent materials. This study proposes creating solar heat collector with modified fluorescent materials, and the new perspective of which demonstrates that the composites have a great potential and application prospect in the solar photothermal field. [ABSTRACT FROM AUTHOR]

The flesh oil content (OC) is a crucial commercial indicator of avocado maturity and directly correlates with its nutritional quality. To meet export standards and optimize edible characteristics, avocados must be harvested at the appropriate stage of physiological maturity. The significant variability in OC during maturation, without any external morphological indicators, poses a longstanding challenge. Currently, harvesting maturity is optimized through time-consuming, destructive laboratory methods like freeze-drying and chemical extraction, which use representative samples to estimate the maturity of entire orchards. In this study, for the first time, we employed fluorescence imaging of avocado skin using 365-nm UV polarized light excitation to estimate the OC in the 'Bacon' avocado cultivar. We developed a surface fluorescence index that strongly correlates with OC, achieving correlation coefficients up to − 0.91. Our non-destructive and rapid approach achieved a cross-validation accuracy with an R2 value of 0.81, enabling the classification of avocados with low and high OC. This pioneering method shows considerable potential for further improvement and refinement. This study lays the groundwork for developing a portable, cost-effective, and real-time method for non-destructive in situ monitoring of avocado OC in the field and its integration into large-scale post-harvest grading systems. [ABSTRACT FROM AUTHOR]

Background: Small molecules play a crucial role in the exploration of physiological pathways and in drug development by targeting deoxyribonucleic acid (DNA). DNA is a central focus for both endogenous and exogenous ligands, which interact directly or indirectly to regulate transcription and replication processes, thus controlling genetic expression in specific cells. Among these molecules, indole derivatives like tryptophan, serotonin, and melatonin are notable for their widespread presence in nature and significant biological effects. Tryptophan, an essential amino acid, serves as a vital structural element in proteins and a precursor for bioactive compounds like serotonin and melatonin, which impact various physiological functions. Methods: Experimental studies have been conducted to reveal the interaction mechanisms of these endogenous indole derivatives with calf thymus DNA (ct-DNA). These investigations involve viscosity measurements and analysis of double-stranded DNA behavior in the presence of indole molecules, using spectrophotometric UV absorption techniques to assess their impact on DNA stability. Additionally, the influence of calcium and magnesium ions on the resulting complexes of these indole derivatives with ct-DNA has been evaluated. Molecular docking validated our findings, offering additional insights into potential DNA–ligand interactions. Utilizing a crystallographic oligomer with an intercalation gap improved docking accuracy, distinguishing intercalation from groove recognition and enhancing assessment precision. Results: Our study offers detailed insights into the interaction patterns of the indole derivatives with DNA and is highly supported by molecular docking analyses: the indole derivatives were predominantly localized between C and G, interacting via π-π interactions and hydrogen bonds and aligning with known data on conventional intercalators. These findings underscore the importance of small compounds' planar structure and appropriate size, facilitating tight insertion between adjacent base pairs and disrupting regular DNA stacking. Conclusions: Indoles' physiological roles and potential as drug candidates targeting specific pathways are highlighted, emphasizing their significance as ubiquitous molecules with the ability to modulate biological effects on DNA structure. [ABSTRACT FROM AUTHOR]

The mechanical properties of sclera play an important role in ocular functions, protection, and disease. Modulating the sclera's properties by exogenous crosslinking offers a way to expand the tissue's range of properties for study of the possible influences on the eye's behavior and diseases such as glaucoma and myopia. The focus of this work was to evaluate the effects of genipin crosslinking targeting the porcine perilimbal sclera (PLS) since the stiffness of this tissue was previously found in a number of studies to influence the eye's intraocular pressure (IOP). The work includes experiments on tensile test specimens and whole globes. The specimen tests showed decreased strain-rate dependence and increased relaxation stress due to the cross-linker. Whole globe perfusion experiments demonstrated that eyes treated with genipin in the perilimbal region had increased IOPs compared to the control globes. Migration of the cross-linker from the target tissue to other tissues is a confounding factor in whole globe, biomechanical measurements, with crosslinking. A novel quantitative genipin assay of the trabecular meshwork (TM) was developed to exclude globes where the TM was inadvertently crosslinked. The perfusion study, therefore, suggests that elevated stiffness of the PLS can significantly increase IOP apart from effects of the TM in the porcine eye. These results demonstrate the importance of PLS biomechanics in aqueous outflow regulation and support additional investigations into the distal outflow pathways as a key source of outflow resistance. [ABSTRACT FROM AUTHOR]

This work aims to amplify the fluorescence of (Z)-4-hetarylidene-5(4H)-oxazolones 1 by suppression of the hula-twist non-radiative deactivation pathway by C^N-orthopalladation of the 4-hetarylidene ring. Different (Z)-4-hetarylidene-2-phenyl-5(4H)-oxazolones, 1a–1c, prepared by the Erlenmeyer–Plöchl method, have been studied. The orthopalladation of (Z)-2-phenyl-4-(5-thiazolylmethylene)-5(4H)-oxazolone (1a) takes place by C-H bond activation of the H4 of the heterocycle and C^N-chelation, giving the dinuclear trifluoroacetate derivative 2a. By further metathesis of bridging ligands in 2a, complexes containing the orthometalated oxazolone and a variety of ligands 3a–5a, were prepared. The study of the photophysical properties of 1a–5a shows that the bonding of the Pd metal to the 4-hetaryliden-5(4H)-oxazolone does not promote, in these cases, an increase in fluorescence. Interestingly, the orthopalladation of (Z)-2-phenyl-4-(4-thiazolylmethylene)-5(4H)-oxazolone (1b) gives orthopalladated 2b, where the incorporation of the Pd to the oxazolone takes place by C-H bond activation of the ortho-H2 of the 2-phenyl group, ring opening of the oxazolone heterocycle and simultaneous N,N-bonding of the N atoms of the thiazole ring and the generated benzamide fragment. This N^N^C-tridentate dianionic bonding mode is obtained for the first time in oxazolones. Despite a similar lock of the hula-twist deactivation, 2b does not show fluorescence. [ABSTRACT FROM AUTHOR]

Objective: To explore the potent effects of denatonium benzoate (DB) on Mas-related G protein-coupled receptor-B2(MrgprB2)-mediated rat mast cell degranulation. Methods: RBL-2H3 cells were treated with DB overnight, before challenged with MrgprB2 ligands substance P (SP). The release of β-hex from MrgprB2-activated RBL-2H3 was detected by substrate method. Detection of LTC4, IL-6, TNF-α and cPLA2 activity were performed by ELISA. The Ca2+ influx and the expression of RBL-2H3 MrgprB2 receptors were measured by fluorescence assay. Results: The results showed 10 µmol/L, 50 µmol/L, 80 µmol/L, 100 µmol/L DB treatments promoted β-hex and LTC4 releases from activated RBL-2H3, accompanied by increased Ca2+ mobilization and cPLA2 activation. DB treatments did not affect IL-6 and TNF-α LTC4 releases in MrgprB2-activated RBL-2H3, as well as the levels of MrgprB2 expression in mast cells. Conclusion: Taken together, DB enhanced the MrgprB2-mediated RBL-2H3 degranulation in vitro, probably by up-regulating Ca2+ mobilization in activated cells. [ABSTRACT FROM AUTHOR]

In this account, we will highlight recent progress in the development of multichannel lanthanide‐doped (MC−Ln) nanoprobes for highly efficient serodiagnosis and therapy, with a particular focus on our own work. First, we first provide a classification of the types of MC−Ln nanoprobes based on the contained type and number of signals. The merits of different types of nanoprobes and the reason using lanthanides are elucidated. Then, we provide an overview of the current uses of MC−Ln nanoprobes in serodiagnosis and therapy, focusing on the strategic exploration to improve the diagnostic and therapeutic performance from different perspectives. Finally, we present a prospective outlook on the future development and potential issues of next‐generation MC−Ln nanoprobes. We hope that this timely account will update our understanding of MC−Ln and similar nanoprobes for bioapplications and provide helpful references for the state‐of‐the‐art tools for serodiagnosis and therapy. [ABSTRACT FROM AUTHOR]

We characterize the subsurface thermal degradation of an inert analog of high-explosive molecular crystals (Eu:Y(acac)3(DPEPO)) (EYAD) embedded inside of a plastic bonded explosive simulant using feedback-assisted wavefront shaping-based fluorescence and Raman spectroscopies. This technique utilizes wavefront shaping to focus pump light inside a heterogeneous material onto a target particle, which significantly improves its spectroscopic signature. We find that embedding the EYAD crystals in the heterogeneous polymer results in improved thermal stability, relative to bare crystal measurements, with the crystal remaining fluorescent to >612 K inside of the heterogeneous material, while the bare crystal's fluorescence is fully quenched by 500 K. We hypothesize that this improvement is due to the polymer restricting the effects of EYAD melting, which occurs at 400 K and is the primary mechanism for spectroscopic changes in the temperature range explored. [ABSTRACT FROM AUTHOR]

Super‐resolution structured‐illumination microscopy (SIM) is a powerful technique that allows one to surpass the diffraction limit by up to a factor two. Yet, its practical use is hampered by its sensitivity to imaging conditions which makes it prone to reconstruction artefacts. In this work, we present FlexSIM, a flexible SIM reconstruction method capable to handle highly challenging data. Specifically, we demonstrate the ability of FlexSIM to deal with the distortion of patterns, the high level of noise encountered in live imaging, as well as out‐of‐focus fluorescence. Moreover, we show that FlexSIM achieves state‐of‐the‐art performance over a variety of open SIM datasets. [ABSTRACT FROM AUTHOR]

Gold-platinum (Au@Pt) nanozymes with high catalytic activity and stability were designed to improve the stability of the enzyme-linked immunosorbent assay (ELISA), and a two-mode signal output was used to enhance the sensitivity and confidence of the assay. This study reports the two-mode signal output based on Au@Pt nanozyme to catalyzed 3,3′,5,5′-tetramethylbenzidine (TMB) reaction. Oxidized 3,3′,5,5′-tetramethylbenzidine (ox-TMB) has wide absorption spectrum, providing excellent optical density capabilities and fluorescence quenching. The detection limits of imidacloprid were 0.88 μg/L and 1.14 μg/L in colorimetric and fluorescence modes, respectively. Multiple-mode strategy improves detection accuracy, increases the confidence of experimental results, and broadens detection modes. Two modes can meet the requirements of accurate and flexible multi-mode sensing in different application situations. [ABSTRACT FROM AUTHOR]

A bilayer MOF reporter (ZIF-67@FAM-mRNA@ZIF-8) was synthesized, and the ZIF-67 was used as a carrier and fluorescent quencher to connect the FAM reporter through electrostatic adsorption and coordination effect. The ZIF-8 covering the outer layer can improve the stability of the probe and cell permeability, which helps the FAM reporter effectively release. After entering the cancer cells, the acidic environment in the cells induced the decomposition of ZIF-8. The excess ATP in the tumor cells competitively binds ZIF-67, causing the FAM reporter to shed and restore fluorescence. The shed FAM reporter was specifically bound to the overexpressed miRNA-21 in breast cancer cells to achieve fluorescence imaging and therapy of breast cancer. The results of specific imaging and apoptosis experiments of breast cancer cells indicate that bilayer MOF nanomachine provides an effective nanotherapy platform for accurate fluorescence imaging. [ABSTRACT FROM AUTHOR]

A fluorescent and photoelectrochemical (PEC) dual-mode biosensor based on target biorecognition-triggered cyclic amplification was constructed for Kana detection. With the assistance of the catalyzed reaction of exonuclease III, a Kana-aptamer DNA duplex was designed for conducting the cyclic release of G-rich DNA sequence as well as output DNA S2. The released G-rich sequence triggers the fluorescence (FL) of thioflavin T (ThT), the intensity of which is positively correlated with the Kana concentration. The linear range is 0.2 to 30 nM, and the detection limit reaches 0.07 nM. Simultaneously, the released output DNA S2 was captured by Fe3O4@CdTe-probe ssDNA and then combined with methylene blue to realize the transduction of polarity-reversed PEC signal, leading to the sensitive detection of Kana with a linear range of 0.2 to 40 nM and a calculated detection limit of 0.2 nM. The outstanding performance endows the dual-mode biosensor a promising prospect for practical application. [ABSTRACT FROM AUTHOR]

A ratiometric fluorescence sensor (Fe-MIL-88-NH2/curcumin) based on luminescent metal–organic frameworks (LMOFs) for the determination of curcumin was constructed. Upon the addition of curcumin, the 535-nm emission of curcumin was enhanced, while the fluorescence emission at 438 nm was quenched, under 367-nm excitation. This sensor demonstrated a broad linear range from 1.5 to 40 μM, a low detection limit of 35 nM, and a fast response time of at most 30 s. We verified the Förster resonance energy transfer (FRET) mechanism between donor (Fe-MIL-88-NH2) and acceptor (curcumin), which further proved the selectivity of the approach. The sensing system enabled the detection of curcumin in the traditional Chinese medicine (TCM) Turmeric. A smartphone-assisted sensing platform was prepared to visually detect curcumin in a portable manner. This study represents the first attempt to fabricate LMOFs for ratiometric fluorescence detection of curcumin, which has promising potential for application in TCM. [ABSTRACT FROM AUTHOR]

Highly stable copper nanocluster (CuNCs) with aggregation-induced emission (AIE) properties was synthesized. α-, β-, and γ- MnO2 were utilized as quenchers, with CuNCs fluorescence quenching of 48.9%, 91.5%, and 96.6%, respectively. L-ascorbate-2-phosphate (AAP) was hydrolyzed by acid phosphatase (ACP), and ascorbic acid (AA) was formed. Then, MnO2 could be restored by AA, and the fluorescence of the CuNCs could be restored. An on–off–on detection platform with a high signal/noise ratio was constructed for the sensing of ACP. The fluorescence recovery rate of the CuNCs was related to the crystal forms of MnO2. Then, the equilibrium constants (K) for the reaction between AA and MnO2 were calculated to evaluate the reaction process. Compared with the K values of CuNCs/α-MnO2 and CuNCs/γ-MnO2, the K values for AA and β-MnO2 were maximum. The CuNCs/β-MnO2 system exhibited optimal fluorescence recovery for the sensitive detection of ACP. In the concentration range 0.005–0.06 U/mL, the detection limit was 0.0028 U/mL. The determination of serum ACP levels also revealed satisfactory results. This study provides novel insights into enhancing the sensitivity of the determination of quenchers in different crystal form. [ABSTRACT FROM AUTHOR]

The design and development of fluorescent materials for detecting cancer-related enzymes are crucial for cancer diagnosis and treatment. Herein, we present a substituted rhodamine derivative for the chromogenic and fluorogenic detection of the cancer-relevant enzyme γ-glutamyltranspeptidase (GGT). Initially, the probe is non-chromic and non-emissive due to its spirolactam form, which hinders extensive electronic delocalization over broader pathway. However, selective enzymatic cleavage of the side-coupled group triggers spirolactam ring opening, resulting in electronic flow across the rhodamine skeleton, and reduces the band gap for low-energy electronic transitions. This transformation turns the reaction mixture from colorless to intense pink, with prominent UV and fluorescence bands. The sensor's selectivity was tested against various human enzymes, including urease, alkaline phosphatase, acetylcholinesterase, tyrosinase, and cyclooxygenase, and showed no response. Absorption and fluorescence titration analyses of the probe upon incremental addition of GGT into the probe solution revealed a consistent increase in both absorption and emission spectra, along with intensified pink coloration. The cellular toxicity of the receptor was evaluated using the MTT assay, and bioimaging analysis was performed on BHK-21 cells, which produced bright red fluorescence, demonstrating the probe's excellent cell penetration and digestion capabilities for intracellular analytical detection. Molecular docking results supported the fact that probe-4 made stable interactions with the GGT active site residues. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) are membrane-enclosed particles that have attracted much attention for their potential in disease diagnosis and therapy. However, the clinical translation is limited by the dosing consistency due to their heterogeneity. Among various characterization techniques, nanoparticle tracking analysis (NTA) offers distinct benefits for EV characterization. In this review, we will discuss the NTA technique with a focus on factors affecting the results; then, we will review the two modes of the NTA techniques along with suitable applications in specific areas of EV studies. EVs are typically characterized by their size, size distribution, concentration, protein markers, and RNA cargos. The light-scattering mode of NTA offers accurate size, size distribution, and concentration information in solution, which is useful for comparing EV isolation methods, storage conditions, and EV secretion conditions. In contrast, fluorescent mode of NTA allows differentiating EV subgroups based on specific markers. The success of fluorescence NTA heavily relies on fluorescent tags (e.g., types of dyes and labeling methods). When EVs are labeled with disease-specific markers, fluorescence NTA offers an effective tool for disease detection in biological fluids, such as saliva, blood, and serum. Finally, we will discuss the limitations and future directions of the NTA technique in EV characterization. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) offer tremendous advantages in the fields such as bioimaging, sensing, biomedicine, catalysis, information encryption, and optoelectronics. However, the inherent challenge is synthesizing CDs with a full-spectrum emission, as most CDs typically produce only blue or green emissions, which severely hinder further investigation into their fluorescence mechanism and restrict their broader applications in light-emitting diodes (LEDs). In this work, we reported a solvent-controlled strategy for the preparation of multicolor CDs with blue, yellow, and red emissions, using o-phenylenediamine (oPD) and ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (BmimPF6) as precursors. The detailed characterizations proved that a solvent with a lower boiling point and lower solubility of precursors resulted in a higher degree of dehydration and carbonization process, thereby increasing carbon cores with sp2-conjugated domains and nitrogen doping and further reducing the bandgap energies, causing a significant redshift emission from blue to red. The underlying fluorescence mechanism of the prepared multicolor CDs was contributed to the surface state. Eventually, blue-, yellow-, and red-emitting CDs based on poly(vinyl alcohol) (PVA) films and colorful LEDs devices were fabricated by dispersing the as-synthesized CDs into a PVA solution. The proposed solvent-controlled strategy for multicolor CDs preparation will be helpful for fully utilizing the advantages of CDs and expanding their applications. [ABSTRACT FROM AUTHOR]

Immunoassays have been widely used for the determination of various analytes in the fields of disease diagnosis, food safety, and environmental monitoring. Dual-signal immunoassays are now advanced and integrated detection technologies with excellent self-correction and self-validation capabilities. In this work, we summarize the recent advances in the development of optical and electrochemical dual-signal immunoassays, including colorimetric, fluorescence, surface-enhanced Raman spectroscopy (SERS), electrochemical, electrochemiluminescence, and photoelectrochemical methods. This review particularly emphasizes the working principle of diverse dual-signal immunoassays and the utilization of dual-functional molecules and nanomaterials. It also outlines the challenges and prospects of future research on dual-signal immunoassays. [ABSTRACT FROM AUTHOR]

An organic fluorescent probe (OFP‐TAR) with a propeller‐like structure was designed and synthesized. The photoluminescence of OFP‐TAR in solution exhibited a significant red shift with the increase of solvent polarity, enabling a transition of fluorescence emission from blue (445 nm) to yellow (540 nm). The organic thin‐film materials based on OFP‐TAR/PMMA exhibit significant color changes upon exposure to CH2Cl2, CHCl3, and CCl4, with their maximum fluorescence wavelengths measured at 445, 471, and 494 nm respectively. The device facilitates the visual detection of chloromethanes and is capable of enduring more than 7 cycles of testing. These materials can also be prepared as binary‐coded microarray data storage devices or applied in the field of anti‐counterfeiting. The quantum yields of guest‐loaded crystals CH2Cl2@OFP‐TAR, CHCl3@OFP‐TAR and CCl4@OFP‐TAR are observed as 19.13 %, 8.79 %, and 0.83 % respectively, which are consistent with the tendency of OFP‐TAR in CH2Cl2 (47.30 %), CHCl3 (34.27 %) and CCl4 (3.10 %). The fluorescence properties of OFP‐TAR, OFP‐TAR/PMMA, guest‐loaded and guest‐free crystals provided insights into the special response mechanism of OFP‐TAR towards different chloromethanes. [ABSTRACT FROM AUTHOR]

Objectives Traditional histopathology is a time-intensive and labor-intensive process involving tissue formalin fixation, paraffin embedding, and microtoming into thin sections for H&E staining. Frozen section analysis is a modality used during surgery to quickly evaluate tissue, but it has limitations, such as the size and number of the specimens that can be analyzed as well as difficulties with fatty and bony tissues. Our objective was to investigate the performance of nonlinear microscopy, a fluorescence microscopy technique, for the rapid examination of resected lung tumors. Methods In this proof-of-principle study, nonlinear microscopy imaging of resected lung tissue was performed on a total of 73 tissue specimens collected from 13 patients who underwent lobectomy, segmentectomy, or wedge resection for pulmonary nodules. Results Two pathologists reviewed the digital nonlinear microscopy images in comparison to the corresponding histopathologic H&E slides from a variety of pulmonary pathologies. Conclusions This study demonstrated that nonlinear microscopy readily replicates traditional H&E staining for both lung tumors and nonneoplastic pulmonary structures. Nonlinear microscopy provides many advantages over frozen section analysis and is an optical imaging platform that has the potential to augment rapid pathologic evaluation of resected tissues in the age of digital pathology. [ABSTRACT FROM AUTHOR]

In this paper, two aggregation-induced emission (AIE) chiral fluorescent materials, S-1 and S-2, were synthesized. The two materials are based on BINOL and H8-BINOL backbones, respectively, and large electron-absorbing groups are attached to the chiral backbones through the Knoevenagel reaction. At the same time, the CD signals of these two chiral fluorescent materials are gradually weakened (fw gradually increases) as they continue to aggregate. However, S-2 underwent a flip-flop from a negative to positive chiral CD signal at fw ≥ 90. And both materials also showed significant enantioselective recognition of lysine, demonstrating their potential as novel chiral fluorescent probes. Among them, the enantioselective fluorescence enhancement ratios (ef) of S-1 and S-2 for lysine were 10.0 and 10.3, respectively, while different degrees of blue shifts were produced by the ICT mechanism during the recognition process. In addition, the self-assembled morphology of the two nanomaterials is different; S-1 comprises hollow-core vesicles that are more likely to aggregate to form larger self-assembled vesicles, whereas S-2 is a solid block structure. When L/D-lysine was added alone, the morphology of S-1 was more distinctly different compared to S-2. With the addition of L-lysine, S-1 was dispersed and regularly spherical, whereas with the addition of D-lysine, S-1 itself remained in the form of aggregated large vesicles. This suggests that both S-1 and S-2 are important in the fields of chiral optics, chiral recognition, and nanoscale self-assembly. [ABSTRACT FROM AUTHOR]

Studying influenza A viruses (IAVs) requires secondary experimental procedures to detect the presence of the virus in infected cells or animals. The ability to generate recombinant (r)IAV using reverse genetics techniques has allowed investigators to generate viruses expressing foreign genes, including fluorescent and luciferase proteins. These rIAVs expressing reporter genes have allowed for easily tracking viral infections in cultured cells and animal models of infection without the need for secondary approaches, representing an excellent option to study different aspects in the biology of IAV where expression of reporter genes can be used as a readout of viral replication and spread. Likewise, these reporter-expressing rIAVs provide an excellent opportunity for the rapid identification and characterization of prophylactic and/or therapeutic approaches. To date, rIAV expressing reporter genes from different viral segments have been described in the literature. Among those, rIAV expressing reporter genes from the viral NS segment have been shown to represent an excellent option to track IAV infection in vitro and in vivo, eliminating the need for secondary approaches to identify the presence of the virus. Here, we summarize the status on rIAV expressing traceable reporter genes from the viral NS segment and their applications for in vitro and in vivo influenza research. [ABSTRACT FROM AUTHOR]

Fluorescent markers play important roles in spectroscopic and microscopic research techniques and are broadly used in basic and applied sciences. We have obtained markers with fluorescent properties, two etheno derivatives of 2-aminopurine, as follows: 1,N2-etheno-2-aminopurine (1,N2-ε2APu, I) and N2,3-etheno-2-aminopurine (N2,3-ε2APu, II). In the present paper, we investigate their interaction with two key enzymes of purine metabolism, purine nucleoside phosphorylase (PNP), and xanthine oxidase (XO), using diffraction of X-rays on protein crystals, isothermal titration calorimetry, and fluorescence spectroscopy. Crystals were obtained and structures were solved for WT PNP and D204N-PNP mutant in a complex with N2,3-ε2APu (II). In the case of WT PNP—1,N2-ε2APu (I) complex, the electron density corresponding to the ligand could not be identified in the active site. Small electron density bobbles may indicate that the ligand binds to the active site of a small number of molecules. On the basis of spectroscopic studies in solution, we found that, in contrast to PNP, 1,N2-ε2APu (I) is the ligand with better affinity to XO. Enzymatic oxidation of (I) leads to a marked increase in fluorescence near 400 nm. Hence, we have developed a new method to determine XO activity in biological material, particularly suitable for milk analysis. [ABSTRACT FROM AUTHOR]

Pro-inflammatory cytokines play a role in the failure of β cells in type 1 and type 2 diabetes. While existing data from 'omics' experiments allow for some understanding of the molecular mechanisms behind cytokine-induced dysfunction in β cells, no report thus far has provided information on the direct imaging of the β cell landscape with nanoscale resolution following cytokine exposure. In this study, we use Airyscan-based optical super-resolution microscopy of Insulinoma 1E (INS-1E) cells to investigate the structural properties of two subcellular membranous compartments involved in the production, maturation and secretion of insulin-containing granules, the endoplasmic reticulum (ER) and the Golgi apparatus (GA). Our findings reveal that exposure of INS-1E cells to IL-1β and IFN-γ for 24 h leads to significant structural alterations of both compartments. In more detail, both the ER and the GA fragment and give rise to vesicle-like structures with markedly reduced characteristic area and perimeter and increased circularity with respect to the original structures. These findings complement the molecular data collected thus far on these compartments and their role in β cell dysfunction and lay the groundwork for future optical microscopy-based ex vivo and in vivo investigations. [ABSTRACT FROM AUTHOR]

Rind thickness (RT) is an important agronomic trait in watermelon [Citrullus lanatus (Thunb.) Mansf.] and affects watermelon storability. However, genetic studies on this trait, as well as gene regulation studies, are scarce and of limited production significance. We constructed a temporary F2 generation using the highly differentiated thick-rind watermelon 'XiaoXiGua-4' and the thin-rind watermelon 'DuanMan' as parents and localized the Cla97C02G044120 gene, which controls the thickness of watermelon rind, to the intervals of chromosome 2, CL2-32303995 and CL2-32316840, through 2 years of genetic analysis. No exonic mutations were found in this gene, but two promoter mutations resulted in changes in the promoter progenitor. Fluorescence quantitative PCR analysis revealed highly significant differences in expression at 1 d and 28 d, and the expression was significantly lower in thick-skinned watermelon varieties. Marker-assisted selection (MAS) for this trait was performed using the Caps marker CL2-32303995 and the InDel marker CL2-32316840, which not only verified the stability of the localization interval but also distinguished thick rind from thin rind. These results can be used for germplasm resource screening and have strong breeding significance. [ABSTRACT FROM AUTHOR]

The memory‐effect‐based speckle auto‐correlation method has gained significant attention for its ability to perform single‐shot noninvasive imaging through scattering media. Despite its advantages, however, not only its imaging field‐of‐view (FOV) is limited by the memory effect (ME), but also the relative positions and orientations of the reconstructed objects beyond ME are lost. Therefore, an approach that enables the reconstruction of multiple objects or a whole object behind scattering media beyond the ME region while accurately preserving the relative positions and orientations of its sub‐objects is proposed. The method achieves this by directly leveraging the correlation of the collected speckle patterns. Experimental results validate the effectiveness of the proposed method. It not only can reconstruct the image of multiple objects or a whole object beyond the ME region simulated by a digital micromirror device but also can reconstruct the image of a fluorescent object beyond the ME region noninvasively, which is well consistent with the theoretical predictions. The method provides a promising pathway for noninvasively visualizing fluorescent objects behind scattering media without being constrained by ME, thereby expanding the imaging FOV. [ABSTRACT FROM AUTHOR]

Identifying the boundary between the tooth and the resin-based composite (RBC) is difficult when replacing restorations. Ultraviolet (UV) light has been reported to assist the viewer by causing the RBC to fluoresce. Using a laboratory-grade fiberoptic spectrometer, 46 RBCs were exposed to UV light from the Woodpecker O-Star curing light. The opalescence and fluorescence were measured relative to a human tooth that contained just dentin and a tooth that contained both enamel and dentin. After these quantitative measurements, 10 RBCs with large differences in light emittance were compared qualitatively to assess their brightness when exposed to UV light compared to the dentin specimen and the specimen containing both enamel and dentin. It was found that, when exposed to UV light, some of the RBCs were less bright compared to the two samples of teeth used for comparison, but most were brighter; some were up to six times brighter. The filler appears to affect the opalescence peaks, while the resin appears to affect the fluorescence peaks. It was concluded that because RBCs emit very different levels of opalescence and fluorescence, UV light from the Woodpecker O-Star cannot be relied upon to detect all brands of RBC on the tooth. The opalescence and fluorescence can also be used to detect changes in the formulation of the RBC. [ABSTRACT FROM AUTHOR]

The degradation of albumin and its constituent amino acids tryptophan, tyrosine, and phenylalanine under the influence of corona discharge cold plasma, pulsed radiation of hot plasma, and 253.7-nm UV light from a mercury lamp has been studied. The concentration of products before and after treatment was determined by measuring the fluorescence yield. The reaction mechanisms leading to protein degradation are oxidation, nitration, and reduction of disulfide bonds. The degree of protein and amino acid degradation is compared with the effect of hydrogen peroxide. The possibility of assessing the bactericidal effectiveness based on fluorescence yield is discussed. [ABSTRACT FROM AUTHOR]

Introduction: Robotic‐assisted surgery has become increasingly popular because of its potential benefits. Anatomical liver resection (ALR) is a valuable strategy in hepatocellular carcinoma (HCC) management. ALR with indocyanine green (ICG) fluorescence navigation was reported as an effective solution for segment identification. We reported a simple and convenient "preoperative positive staining technique" for laparoscopic ALR to overcome some limitations. To our knowledge, this is the first report of robotic‐assisted surgery in which ALR was performed using this technique. Materials and Surgical Technique: A 69‐year‐old man presented with a 12‐mm HCC in segment 8. Preoperative three‐dimensional simulation images showed that the fourth‐order branch of the portal vein was a tumor‐bearing portal pedicle. After anesthesia induction, 1 mL of 0.025 mg/mL ICG was injected percutaneously into this branch under B‐mode ultrasound guidance before pneumoperitoneum. A robotic laparoscope was inserted. The preoperative positive staining area was clearly stained on the liver surface with the Firefly mode on the da Vinci Xi system. Based on the demarcation line, the liver parenchymal resection was started. The ICG fluorescence staining area was checked frequently on the resected side of the liver transection plane. Subsequently, the fourth‐order portal branch was identified with the ICG fluorescence technique and ligated. Finally, the specimen was resected. The operation took 352 min, with 10 mL of blood loss, and was completed without any operative problems. Discussion: Although many cases are required, the proposed preoperative positive staining technique appears useful for accurate and precise surgery given the increasing application of robotic‐assisted hepatectomy. [ABSTRACT FROM AUTHOR]