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Single wall carbon nanotubes (SWCNTs) functionalized with (bio-)polymers such as DNA are soluble in water and sense analytes by analyte-specific changes of their intrinsic fluorescence. Such SWCNT-based (bio-)sensors translate the binding of a molecule (molecular recognition) into a measurable optical signal. This signal transduction is crucial for all types of molecular sensors to achieve high sensitivities. Although there is an increasing number of SWCNT-based sensors, there is yet no molecular understanding of the observed changes in the SWCNT's fluorescence. Here, we report THz experiments that map changes in the local hydration of the solvated SWCNT upon binding of analytes such as the neurotransmitter dopamine or the vitamin riboflavin. The THz amplitude signal serves as a measure of the coupling of charge fluctuations in the SWCNTs to the charge density fluctuations in the hydration layer. We find a linear (inverse) correlation between changes in THz amplitude and the intensity of the change in fluorescence induced by the analytes. Simulations show that the organic corona shapes the local water, which determines the exciton dynamics. Thus, THz signals are a quantitative predictor for signal transduction strength and can be used as a guiding chemical design principle for optimizing fluorescent biosensors. SWCNTs are pivotal optical molecular sensors, but until now, the underlying mechanism how the binding of analytes affects the fluorescence remained elusive. This study has elucidated that coupling between exciton-coupled plasmon modes of SWCNTs and THz water modes is a significant factor. [ABSTRACT FROM AUTHOR]

Analyzing three-dimensional excitation-emission matrix (3D-EEM) spectra through machine learning models has drawn increasing attention, whereas the reliability of these machine learning models remains unclear due to their "black box" nature. In this study, the convolutional neural network (CNN) for classifying numbers of fluorescent components in 3D-EEM spectra was interpreted by gradient-weighted class activation mapping (Grad-CAM), guided Grad-CAM, and structured attention graphs (SAGs). Results showed that the original CNN classifier with high classification accuracy may make a classification based on misleading attention to the non-fluorescence area in 3D-EEM spectra. By removing Rayleigh scatterings in 3D-EEM spectra and integrating convolutional block attention module (CBAM) in CNN classifiers, the correct attention of the trained CNN classifier with CBAM greatly increased from 17.6% to 57.2%. This work formulated strategies for improving CNN classifiers associated with environmental fields and would provide great help for water determination in both natural and artificial environments. [ABSTRACT FROM AUTHOR]

Coumarins still remain one of the most widely explored fluorescent dyes, with a broad spectrum of applications spanning various fields, such as molecular imaging, bioorganic chemistry, materials chemistry, or medical sciences. Their fluorescence is strongly based on a push‐pull mechanism involving an electron‐donating group (EDG), mainly located at the C7 or C8 positions of the dye core. Unfortunately, up to now, these positions have been very limited to hydroxyl or amino groups. In this study, we present in detail the synthesis of the first series of coumarins bearing a vinyl sulfide as the EDG at the C7 position. These derivatives were prepared by thiol‐yne reaction, promoted by ruthenium‐ or porphyrin‐based photoredox catalysis, enabling rapid late‐stage diversification. We also functionalized coumarins with short peptides, and BSA protein as a proof‐of‐concept study, in a single‐step process. This strategy, capable of proceeding under aqueous conditions, overcomes the protection/deprotection steps usually required by traditional methods, which also use strong bases and organic solvents. Moreover, the photophysical properties such as absorption and emission of obtained coumarins (for 3‐CF3, 3‐benzothiazole, 6–8‐difluoro derivatives), predominantly exhibited large Stokes shifts (up to 204 nm) and maintained intramolecular charge transfer (ICT) characteristics. [ABSTRACT FROM AUTHOR]

Phytoplankton are a major source of primary productivity. Their photosynthetic fluorescence are unique measures of their type, physiological state, and response to environmental conditions. Changes in phytoplankton photophysiology are commonly monitored by bulk fluorescence spectroscopy, where gradual changes are reported in response to different perturbations, such as light intensity changes. What is the meaning of such trends in bulk parameters if their values report ensemble averages of multiple unsynchronized cells? To answer this, we developed an experimental scheme that enables tracking fluorescence intensities, brightnesses, and their ratios, as well as mean photon nanotimes equivalent to mean fluorescence lifetimes, one cell at a time. We monitored three different phytoplankton species during diurnal cycles and in response to an abrupt increase in light intensity. Our results show that we can define specific subpopulations of cells by their fluorescence parameters for each of the phytoplankton species, and in response to varying light conditions. Importantly, we identify the cells undergo well‐defined transitions between these subpopulations. The approach shown in this work will be useful in the exact characterization of phytoplankton cell states and parameter signatures in response to different changes these cells experience in marine environments, which will be applicable for monitoring marine‐related environmental effects. [ABSTRACT FROM AUTHOR]

In this work, we report on five novel coordination polymers (CPs) based on the linkage of the [Cd(6apic)2] building block [where 6apic = 6-aminopicolinate] by different bipyridine-type organic spacers, forming different coordination compounds with the following formulae: [Cd(μ-6apic)2]n (1), {[Cd(6apic)2(μ-bipy)]·H2O}n (2), {[Cd(6apic)2(μ-bpe)]·2H2O}n (3), [Cd(6apic)(μ-6apic)(μ-bpa)0.5]n (4) and {[Cd2(6apic)4(μ-tmbp)]·7H2O}n (5) [where bipy = 4,4′-bipyridine, bpe = 1,2-di(4-pyridyl)ethylene, bpa = 1,2-di(4-pyridyl)ethane (bpa) and tmbp = 1,3-di(4-pyridyl)propane]. Most of the synthesized compounds form infinite metal–organic rods through the linkage of the building block by the bipyridine-type linker, except in the case of compound 4 whose assembly forms a densely packed 3D architecture. All compounds were fully characterized and their photoluminescence properties were studied experimentally and computationally through density functional theory (DFT) calculations. All compounds display, upon UV excitation, a similar blue emission of variable intensity depending on the linker employed for the connection of the building units, among which compound 2 deserves to be highlighted for its room temperature phosphorescence (RTP) with an emission lifetime of 32 ms that extends to 79 ms at low temperature. These good photoluminescence properties, in addition to its stability in water over a wide pH range (between 2 and 10), motivated us to study compound 2 as a sensor for the detection of metal ions in water, and it showed high sensitivity to Fe3+ through a fluorescence turn-off mechanism and an unspecific turn-on response to Zn2+. Furthermore, the compound is processed as a paper-based analytical device (PAD) in which the phosphorescence emission is preserved, improving the sensing capacity toward Fe3+ ions. [ABSTRACT FROM AUTHOR]

Fluorescence/luminescence bioimaging, utilizing rare‐earth doped nanocrystals (RENCs) within the NIR‐IIb (1500–1700 nm) sub‐window, has drawn interest for its deep penetration depth and superior resolution. Herein, Er3+/Yb3+ couple is rationally designed in topologically arranged RENCs that facilitate a boosted 1530 nm emission of Er3+ via premeditated Yb3+‐mediated energy transfer processes under 808 nm excitation. To maximize this modulation effect for boosting 1530 nm emission, a regional active ions concentration and spatial regulation strategy is explored in the optimized concentration and core–shell–shell structure (NaErF4:20%Yb@NaYbF4:20%Er@NaYF4 with a quantum yield of 16.46% in NIR‐IIb region). Leveraging the superior emission and multi‐wavelength excitation characteristics of the as‐obtained nanocrystals, a NIR‐IIb‐based ratiometric fluorescence imaging measurement is achieved under 808 and 980 nm excitation, which cannot only show the 2D distribution of probes but also provide spatial depth information (range from 0 to 2.8 mm with a tissue depth resolution of 66 µm). The findings hold significant potential for advancing both vascular science and clinical medicine. [ABSTRACT FROM AUTHOR]

Carbon nanodots (CDs) possess exceptional fluorescence properties, which have been extensively studied in the fields of fluorescence detection and anti‐counterfeiting information. However, the exploration of CDs with simple and fast synthesis paths, secure, and efficient encryption properties, remains a challenge. The rapid synthesis of orange CDs (O‐CDs) is reported with a high photoluminescence quantum yield (PLQY) of 57.6% within 10 min at atmospheric pressure using a one‐step pyrolysis method. The O‐CDs exhibit a dual‐emission property, with a blue emission peak at 425 nm and a strong orange emission peak at 590 nm. The dual‐emission peaks of O‐CDs can allow for fast orange/blue switching of fluorescence color with changes in the acid‐base environment. O‐CDs can serve as effective fluorescent probes for pH detection, depending on their fluorescence wavelength and intensity. Additionally, O‐CDs have potential for fluorescence anti‐counterfeiting. When exposed to NH3 gas, O‐CDs fluorescent ink rapidly (1 s) transitions from orange fluorescence to blue fluorescence, and then quickly (4 s) reverts back to orange fluorescence when the gas environment changes to HCl gas atmosphere. Thus, O‐CDs fluorescent inks offer several advantages, including high fluorescence intensity, fast response, recyclability, and lossless encryption/decryption in "on‐off‐on" double encryption anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

Photoswitchable fluorescent systems based on photochromic derivatives have various applications, including high‐resolution imaging and information processing. In this context, a key objective is to control, manipulate, and improve the fluorescence photoswitching of molecular systems. Herein, the intriguing zero‐order photokinetics properties of a photochromic‐fluorescent dyad made of one perylenediimide fluorophore (PDI) and two diarylethene photochromes (DAE) are reported, in the nanoparticles state, resulting from efficient intra‐ and intermolecular energy transfer processes from the PDI to the DAE, well‐rationalized by modified photokinetics equations for photochromism. It allowed the fine‐tuning of the photokinetics, leading to either classical or unconventional behavior, depending on the irradiation wavelength. Fluorescence photoswitching is investigated under a microscope, demonstrating a sigmoidal profile for fluorescence recovery which can be satisfyingly reproduced by a suitable mathematical model that is developed. These findings represent a significant advance in the development of enhanced photoswitchable fluorescent systems, showing high contrast, driven by few photons with tunable switching rates. [ABSTRACT FROM AUTHOR]

Accurate assessment of food freshness is critical to maintaining human health. However, the complex environment of food usually leads to false‐positive measurements result. Therefore, the development of sensing platforms with self‐calibration for accurate detection of food freshness in complex environments is essential. Here, using the green fluorescence‐emitting FITC‐ene and the red fluorescence‐emitting DBA‐ene‐Eu3+ as fluorescent units, fluorescent polymeric materials P1‐P4 with excitation wavelength‐dependent (254 and 365 nm, matched with standard UV lamp) emission are prepared. P1‐P4 responded rapidly to biogenic amines (BAs). Among them, P3 exhibits the widest linear range, and the most noticeable fluorescence color change (from orange‐red to yellow‐green) under 254 nm excitation and enhanced green fluorescence under 365 nm excitation. The changes of P3‐prepared labels at different excitation wavelengths can be utilized to rapidly evaluate the food's freshness. Furthermore, by using a smartphone to read the Red/Green/Blue values of the labels, the total volatile basic nitrogen (TVBN) values can be output to quantitatively evaluate the food freshness, and the output TVBN values at different excitation wavelengths are utilized for mutual calibration to improve the accuracy of the estimation results. This self‐calibrating sensing platform is fast and nondestructive, which provides an effective method for the accurate evaluation of food freshness. [ABSTRACT FROM AUTHOR]

Fluorescence microscopic imaging is essentially a convolution process distorted by random noise, limiting critical parameters such as imaging speed, duration, and resolution. Though algorithmic compensation has shown great potential to enhance these pivotal aspects, its fidelity remains questioned. Here we develop a physics-rooted computational resolution extension and denoising method with ensured fidelity. Our approach employs a multi-resolution analysis (MRA) framework to extract the two main characteristics of fluorescence images against noise: across-edge contrast, and along-edge continuity. By constraining the two features in a model-solution framework using framelet and curvelet, we develop MRA deconvolution algorithms, which improve the signal-to-noise ratio (SNR) up to 10 dB higher than spatial derivative based penalties, and can provide up to two-fold fidelity-ensured resolution improvement rather than the artifact-prone Richardson-Lucy inference. We demonstrate our methods can improve the performance of various diffraction-limited and super-resolution microscopies with ensured fidelity, enabling accomplishments of more challenging imaging tasks. [ABSTRACT FROM AUTHOR]

The "green synthesis" method is environmentally benign and cost-effective. This research study adopted an environmentally compatible method for creating Zinc oxide nanoparticles (ZnO NPs) using the capping element Solanum nigrum leaf extract. The X-ray diffraction, Fourier transforms infrared spectroscopy, energy dispersive X-ray analysis, UV-visible spectroscopy, fluorescence spectroscopy, field emission scanning electron microscopy, and antibacterial investigations were employed to evaluate the structural, spectroscopic, and antibacterial characterizations of the green synthesized ZnO NPs. It was shown that the generated ZnO NPs had a typical particle size of 27.75 nm and a wurtzite hexagonal form. FTIR spectroscopy has confirmed the presence of the functional groups in the generated sample. By using EDX analysis, the ZnO NPs' fabrication and chemical composition have been determined. The surface texture and aggregation of nanostructure entities were examined using FESEM micrographs. Based on UV-Vis investigations, the bandgap of the ZnO NP was calculated to be 3.82 eV. The fluorescent spectra revealed a significant emission peak at 542 nm (green) for an excitation wavelength of 270 nm. The broad Stokes shift observed in fluorescent spectra is beneficial for practical purposes. The results of the antibacterial test shows that the as-synthesized ZnO NPs can be used in the healthcare and environmental sectors to prevent the growth of harmful bacteria. This work used a leaf extract from Solanum nigrum in a green synthesis process for producing zinc oxide nanoparticles (ZnO NPs). The experiment findings show that the green synthesized ZnO NPs are an excellent choice for applications in the food, pharmaceutical, and environmental industries since they can prevent the growth of potentially dangerous microbes. [ABSTRACT FROM AUTHOR]

Motivated by the scarcity of prior research, in this study we report the synthesis and photophysical characteristics of newly obtained benzanthrone ethynyl derivatives. Fourier-transform infrared spectroscopy, 1H and 13C nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry elucidated the structures of the compounds. To study photophysical characteristics, absorbance and emission spectra were measured in solvents with different polarities. Photofading proved high stability of the synthesized compounds (up to 96% of initial absorption after irradiation for 4 h). The analyzed compounds are fluorescent (quantum yields from 0.01 to 0.74 in ethanol) with a significant solvatochromic effect (from 466 nm in benzene to 720 nm in dimethyl sulfoxide). Based on these findings, there is a correlation between the electronic nature of substituents and photophysical parameters. Hence, these compounds could find applications as probes in fluorescence microscopy and sensors to detect polarity variations. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) in the caudate lobe presents surgical challenges due to the lack of distinct anatomical landmarks. This case report introduces a novel surgical approach combining Takasaki's classification and indocyanine green negative counterstaining for precise anatomical caudate lobectomy. A 78-year-old patient with hepatocellular carcinoma in the caudate lobe underwent surgery following preoperative volumetric assessment. The method involved a glissonian approach for both left and right pedicles, coupled with meticulous dissection of hepatic pedicles of the caudate lobe guided by taping of left and right glissonian pedicles, followed by indocyanine green administration for improved visualization of caudate lobe boundaries. The procedure enabled complete tumor resection with minimal blood loss. At 50 months postsurgery, the patient maintains favorable liver function and performance status. This innovative approach offers a promising solution for precise resection of caudate lobe hepatocellular carcinoma, potentially improving surgical outcomes and long-term prognosis. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is a light-based anticancer therapy that can induce tumor necrosis and/or apoptosis. Two important factors contributing to the efficacy of PDT are the concentration of the photosensitizer in the tumor tissue and its preferential accumulation in the tumor tissue compared to that in normal tissues. In this study, we investigated the use of optical imaging for monitoring whole-body bio-distribution of the fluorescent (660 nm) photosensitizer Bremachlorin in vivo, in a murine pancreatic ductal adenocarcinoma (PDAC) model. Moreover, we non-invasively, examined the induction of tumor necrosis after PDT treatment using near-infrared fluorescent imaging of the necrosis avid cyanine dye IRDye®-800CW Carboxylate. Using whole-body fluorescence imaging, we observed that Bremachlorin preferentially accumulated in pancreatic tumors. Furthermore, in a longitudinal study we showed that 3 hours after Bremachlorin administration, the fluorescent tumor signal reached its maximum. In addition, the tumor-to-background ratio at all-time points was approximately 1.4. Ex vivo, at 6 hours after Bremachlorin administration, the tumor-to-muscle or -normal pancreas ratio exhibited a greater difference than it did at 24 hours, suggesting that, in terms of efficacy, 6 hours after Bremachlorin administration was an effective time point for PDT treatment of PDAC. In vivo administration of the near infrared fluorescence agent IRDye®-800CW Carboxylate showed that PDT, 6 hours after administration of Bremachlorin, selectively induced necrosis in the tumor tissues, which was subsequently confirmed histologically. In conclusion, by using in vivo fluorescence imaging, we could non-invasively and longitudinally monitor, the whole-body distribution of Bremachlorin. Furthermore, we successfully used IRDye®-800CW Carboxylate, a near-infrared fluorescent necrosis avid agent, to image PDT-induced necrotic cell death as a measure of therapeutic efficacy. This study showed how fluorescence can be applied for optimizing, and assessing the efficacy of, PDT. [ABSTRACT FROM AUTHOR]

Purpose: We recently developed an optical instrument to non-invasively detect fluorescently labeled circulating tumor cells (CTCs) in mice called 'Diffuse in vivo Flow Cytometry' (DiFC). OTL38 is a folate receptor (FR) targeted near-infrared (NIR) contrast agent that is FDA approved for use in fluorescence guided surgery of ovarian and lung cancer. In this work, we investigated the use OTL38 for in vivo labeling and detection of FR + CTCs with DiFC. Procedures: We tested OTL38 labeling of FR + cancer cell lines (IGROV-1 and L1210A) as well as FR- MM.1S cells in suspensions of Human Peripheral Blood Mononuclear cells (PBMCs) in vitro. We also tested OTL38 labeling and NIR-DIFC detection of FR + L1210A cells in blood circulation in nude mice in vivo. Results: 62% of IGROV-1 and 83% of L1210A were labeled above non-specific background levels in suspensions of PBMCs in vitro compared to only 2% of FR- MM.1S cells. L1210A cells could be labeled with OTL38 directly in circulation in vivo and externally detected using NIR-DiFC in mice with low false positive detection rates. Conclusions: This work shows the feasibility of labeling CTCs in vivo with OTL38 and detection with DiFC. Although further refinement of the DiFC instrument and signal processing algorithms and testing with other animal models is needed, this work may eventually pave the way for human use of DiFC. [ABSTRACT FROM AUTHOR]

Due to the limitations on the depth of field of high-resolution fluorescence microscope, it is difficult to obtain an image with all objects in focus. The existing image fusion methods suffer from blocking effects or out-of-focus fluorescence. The proposed multi-focus image fusion method based on local maximum luminosity, intensity variance and the information filling method can reconstruct the all-in-focus image. Moreover, the depth of tissue's surface can be estimated to reconstruct the 3D surface model. [ABSTRACT FROM AUTHOR]

Zn-Ag-In-S (ZAIS) quantum dots (QDs) were synthesized with various Ag-to-In ratios and used as novel photosensitizers for photodynamic therapy (PDT) on cancer cell inhibition and bacterial sterilization, and their structural, optical, and photodynamic properties were investigated. The alloyed QDs displayed a photoluminescence quantum yield of 72% with a long fluorescence lifetime of 5.3 μs when the Ag-to-In ratio was 1:3, suggesting a good opportunity as a dual functional platform for fluorescence imaging and PDT. The ZAIS QDs were then coated with amphiphilic brush copolymer poly(maleic anhydride-alt-1-octadecene) (PMAO) before application. The 1O2 quantum yield of the ZAIS/PMAO was measured to be 8%, which was higher than previously reported CdSe QDs and comparable to some organic photosensitizers. Moreover, the ZAIS QDs showed excellent stability in aqueous and biological media, unlike organic photosensitizers that tend to degrade over time. The in vitro PDT against human melanoma cell line (A2058) and Staphylococcus aureus shows about 30% inhibition rate upon 20 min light irradiation. Cell staining images clearly demonstrated that co-treatment with ZAIS QDs and light irradiation effectively killed A2058 cells, demonstrating the potential of ZAIS QDs as novel and versatile photosensitizers for PDT in cancer and bacterial treatment, and provides useful information for future designing of QD-based photosensitizers. [ABSTRACT FROM AUTHOR]

The application of iron oxide quantum dots (IOQDs) in this study led to the development of a straightforward, easy, and selective approach for cytosine sensing. To examine the capability of IOQDs in detecting nucleobases, attempts have been made to gain insight into the characteristics of IOQDs, including UV/Vis spectroscopic analysis, infrared spectroscopy, fluorescence spectroscopy, transmission electron microscopy, and powder‐XRD. We introduced IOQDs with a mean particle size distribution of 5.71 ± 0.08 nm for detecting cytosine by harnessing a turn‐on fluorescence phenomenon. The fostering fluorescence response of IOQDs was triggered in the presence of cytosine. In comparison, the presence of other nucleobases did not further induce the fluorescence signal of IOQDs. It was concluded that the hydrogen bonding bridging the carboxylate and hydroxyl groups on the surface of QDs with the amine groups of cytosine results in the elevation of IOQDs fluorescence. [ABSTRACT FROM AUTHOR]

Biofilms are known to be present in tonsils, but little is known about their spatial location and size distribution throughout the tonsil. Studies of the location and distribution of biofilms in tonsil specimens have thus far been limited to either high‐magnification methods such as electron microscopy, which enables high‐resolution imaging but only from a tiny tissue volume, or lower magnification techniques such as light microscopy, which allow imaging of larger specimens but with poor spatial resolution. To overcome these limitations, we report the use of multimodal optical mesoscopy to visualise and quantify the number and spatial distribution of Gram‐positive biofilms in fresh, excised paediatric tonsils. This methodology supports simultaneous imaging of both the tonsil host and biofilms in whole mounts of tissue up to 5 mm × 5 mm × 3 mm with subcellular resolution throughout. A quantitative assessment of 36 tonsil specimens revealed no statistically significant difference between biofilm presence on the tonsil surface and the interior of the tonsil. This new quantitative mesoscale imaging approach may prove useful in understanding the role of biofilms in tonsillar diseases and other infections. LAY DESCRIPTION: Biofilms, which are communities of bacteria known to be more resistant to antibiotics than normal (planktonic) bacteria, are thought to play a role in diseases of the tonsil. Biofilms are difficult to study in patient tissue due to limits in standard microscopes, which compromise either on the tissue volume that can be studied or the amount of detail in the image. We have used the Mesolens, a novel microscope lens, to visualise bacteria and biofilms in unusually large volumes of freshly excised tonsils from a local children's hospital following tonsillectomy. Using this method, we have shown that biofilms were present in all diseased tonsils on both the surface and the interior of the tonsil. This new way of studying diseases in human tissue may prove useful in understanding the role of biofilms in other diseases and infections. [ABSTRACT FROM AUTHOR]

Introduction: The European Association of Urology (EAU) and the American Society of Clinical Oncology (ASCO) recently issued updated guidelines on penile cancer, emphasising dynamic sentinel node biopsy (DSNB) as the preferred method for surgical staging among patients with invasive penile tumours and no palpable inguinal lymphadenopathy. This paper outlines the rationale behind this new recommendation and describes remaining challenges, as well as strategies for promoting DSNB worldwide. Main text: DSNB offers high diagnostic accuracy with the lowest postoperative complications compared to open or minimally invasive inguinal lymph node dissection (ILND), prompting its preference in the new guidelines. Nevertheless, despite its advantages, there are challenges hampering the widespread adoption of DSNB. This includes the false-negative rate associated with DSNB and the potential negative impact on patient outcome. To address this issue, improvements should be made in several areas, including refining the timing and interpretation of the lymphoscintigraphy and the single photon emission computed tomography/computed tomography images. In addition, the quantity of tracer employed and choice of the injection site for the radiopharmaceutical should be optimised. Finally, limiting the removal of nodes without tracer activity during surgery may help minimise complication rates. Conclusion: Over the years, DSNB has evolved significantly, related to the dedicated efforts and innovations in nuclear medicine and subsequent clinical studies validating its efficacy. It is now strongly recommended for surgical staging among selected penile cancer patients. To optimise DSNB further, multidisciplinary collaborative research is required to improve SN identification for better diagnostic accuracy and fewer complications. [ABSTRACT FROM AUTHOR]

Background: To date, the benefit of image guidance during robot-assisted surgery (IGS) is an object of debate. The current study aims to address the quality of the contemporary body of literature concerning IGS in robotic surgery throughout different surgical specialties. Methods: A systematic review of all English-language articles on IGS, from January 2013 to March 2023, was conducted using PubMed, Cochrane library's Central, EMBASE, MEDLINE, and Scopus databases. Comparative studies that tested performance of IGS vs control were included for the quantitative synthesis, which addressed outcomes analyzed in at least three studies: operative time, length of stay, blood loss, surgical margins, complications, number of nodal retrievals, metastatic nodes, ischemia time, and renal function loss. Bias-corrected ratio of means (ROM) and bias-corrected odds ratio (OR) compared continuous and dichotomous variables, respectively. Subgroup analyses according to guidance type (i.e., 3D virtual reality vs ultrasound vs near-infrared fluoresce) were performed. Results: Twenty-nine studies, based on 11 surgical procedures of three specialties (general surgery, gynecology, urology), were included in the quantitative synthesis. IGS was associated with 12% reduction in length of stay (ROM 0.88; p = 0.03) and 13% reduction in blood loss (ROM 0.87; p = 0.03) but did not affect operative time (ROM 1.00; p = 0.9), or complications (OR 0.93; p = 0.4). IGS was associated with an estimated 44% increase in mean number of removed nodes (ROM 1.44; p < 0.001), and a significantly higher rate of metastatic nodal disease (OR 1.82; p < 0.001), as well as a significantly lower rate of positive surgical margins (OR 0.62; p < 0.001). In nephron sparing surgery, IGS significantly decreased renal function loss (ROM 0.37; p = 0.002). Conclusions: Robot-assisted surgery benefits from image guidance, especially in terms of pathologic outcomes, namely higher detection of metastatic nodes and lower surgical margins. Moreover, IGS enhances renal function preservation and lowers surgical blood loss. [ABSTRACT FROM AUTHOR]

Resection of high-grade glioma with sodium fluorescein can improve the resection rate of the glioma and improve survival. However, it is unclear whether the yellow fluorescence boundary of the high-grade glioma is consistent with the actual boundary of the tumor. This study explores the yellow fluorescence boundary and the actual tumor boundary in high-grade glioma surgery. This is a retrospective analysis of 10 patients with high-grade gliomas who underwent tumor visualization with sodium fluorescein. After staining of the tumor, random selections of both developed and non-developed yellow fluorescent border tissue at the fluorescence chromogenic boundary were made, followed by pathological examination. Claudin-5, an important component of the tight connections between vascular endothelial cells, was assessed by immunohistochemistry and qRT-PCR in the tumor and surrounding tissues in order to determine the tumor cell content of the tissue, blood-brain barrier damage, and vascular proliferation. The yellow fluorescence boundary was compared with the actual tumor boundary and the results analyzed. Tumor cells were still detected outside the yellow fluorescence boundary during high-grade glioma surgery (P < 0.05). Claudin-5 expression was higher in high-grade gliomas than in adjacent normal tissues (P < 0.05), while disconnected Claudin-5 expression was associated with intraoperative yellow fluorescence imaging (r = 0.67). There is a difference between the yellow fluorescence boundary and the actual boundary of the tumor in high-grade glioma, and there are glioma cell infiltrations in the brain tissue of the undeveloped yellow fluorescent border. To ensure patient recovery and function, it is recommended that tumor resection be expanded based on yellow fluorescence visualization. Claudin-5 is overall up-regulated in high-grade gliomas, but some Claudin-5 expression is disconnected. This Claudin-5 expression pattern may be related to the development of yellow fluorescence. [ABSTRACT FROM AUTHOR]

A label-free fluorescence sensor for selective detection of dopamine (DA) was developed by using graphene quantum dots (GQDs) as fluorescence probes. The GQDs were prepared via a top-down acid vapor oxidation strategy, in which a hollow carbon @ mesoporous silica nanosphere (h-C@mesoSiO2) serves as nanoreactor and only 1 mL of HNO3 was used as scissors for quickly cleaving the thin carbon layer in the nanospace of h-C@mesoSiO2. The method not only effectively avoids a tedious separation process but also endows GQDs with uniform size and good dispersion. And the as-prepared GQDs display good linear fluorescence response to DA in the range of 0.24–5.86 mM with a low detection limit of 12.7 nM. The proposed sensor shows high selectivity and satisfying recovery for DA detection in human urine. The good specificity toward DA may be due to a) the carboxyl groups on the surface of GQDs can interact with the amine functional groups in DA through electrostatic interactions and b) this specificity is further enhanced by the π–π interaction between GQDs and DA. Importantly, the work not only provides an avenue for the controllable synthesis of GQDs, but also expands the application of GQDs prepared by top-down method to DA sensor. [ABSTRACT FROM AUTHOR]

Background: Preserving sufficient oxygen supply to the tissue is fundamental for maintaining organ function. However, our ability to identify those at risk and promptly recognize tissue hypoperfusion during abdominal surgery is limited. To address this problem, we aimed to develop a new method of perfusion monitoring that can be used during surgical procedures and aid surgeons' decision-making. Methods: In this experimental porcine study, thirteen subjects were randomly assigned one organ of interest [stomach (n = 3), ascending colon (n = 3), rectum (n = 3), and spleen (n = 3)]. After baseline perfusion recordings, using high-frequency, low-dose bolus injections with weight-adjusted (0.008 mg/kg) ICG, organ-supplying arteries were manually and completely occluded leading to hypoperfusion of the target organ. Continuous organ perfusion monitoring was performed throughout the experimental conditions. Results: After manual occlusion of pre-selected organ-supplying arteries, occlusion of the peripheral arterial supply translated in an immediate decrease in oscillation signal in most organs (3/3 ventricle, 3/3 ascending colon, 3/3 rectum, 2/3 spleen). Occlusion of the central arterial supply resulted in a further decrease or complete disappearance of the oscillation curves in the ventricle (3/3), ascending colon (3/3), rectum (3/3), and spleen (1/3). Conclusion: Continuous organ-perfusion monitoring using a high-frequency, low-dose ICG bolus regimen can detect organ hypoperfusion in real-time. [ABSTRACT FROM AUTHOR]

The advancement of the aviation sector has made the temperature measurement technology for aero-engine turbine blades essential for maintaining the engine's safe and steady performance. The non-contact temperature measurement technology is a trending research focus in turbine blade temperature measurement due to its benefits of not requiring direct touch with the object being measured and its suitability for high-temperature and high-speed conditions. This paper provides a concise overview of various key non-contact temperature measurement methods for aero-engines, such as fluorescence temperature measurement, fiber-optic temperature measurement, and radiation temperature measurement. It discusses the temperature measurement principle, technical characteristics, and the current research status both domestically and internationally. Based on this, this Review further discusses the main challenges faced by the non-contact temperature measurement technology and the development trend of the future. [ABSTRACT FROM AUTHOR]

This review focuses on optical properties of compounds in which at least one phosphonate group is directly attached to a heteroaromatic ring. Additionally, the synthesis and other applications of these compounds are addressed in this work. The influence of the phosphonate substituent on the properties of the described compounds is discussed and compared with other non-phosphorus substituents, with particular attention given to photophysical properties, such as UV-Vis absorption and emission, fluorescence quantum yield and fluorescence lifetime. Considering the presence of heteroatom, the collected material was divided into two parts, and a review of the literature of the last thirty years on heteroaryl phosphonates containing sulfur and nitrogen atoms in the aromatic ring was conducted. [ABSTRACT FROM AUTHOR]

We report on the synthesis of two fluorescent probes which can be activated by β-Galactosidase (β-Gal) enzymes and/or light. The probes contained 2-nitro-4-oxybenzyl and 3-nitro-4-oxybenzyl fragments, with β-Gal residues linked to C-4. We performed the enzymatic and photoactivation of the probes in a cuvette and compared them, prior to the labeling of Vimentin–Halo fusion protein in live cells with overexpressed β-galactosidase. The dye fluorescence afforded the observation of enzyme activity by means of confocal and super-resolution optical microscopy based on stimulated emission depletion (STED). The tracing of enzymatic activity with the retention of activated fluorescent products inside cells was combined with super-resolution imaging as a tool for use in biomedicine and life science. [ABSTRACT FROM AUTHOR]

This study explores the impact of sulfur oxidation on the structural, optical, and electronic properties of [1]benzothieno[3,2-b][1]benzothiophene (BTBT) derivatives, specifically focusing on 2,7-dibromo BTBT (2,7-diBr-BTBT) and its oxidized forms, 5,5-dioxide (2,7-diBr-BTBTDO) and 5,5,10,10–tetraoxide (2,7-diBr-BTBTTO). The bromination of BTBT followed by sequential oxidation with m-chloroperoxybenzoic acid yielded the target compounds in good yields. They were characterized using a wide array of analytical techniques including different spectroscopic methods, X-ray analysis, thermal analysis, and quantum chemical calculations. The results revealed that sulfur oxidation significantly alters the crystal packing, thermal stability, and optoelectronic properties of BTBT derivatives. Notably, the oxidized forms exhibited increased thermal stability and enhanced emission properties, with quantum yields exceeding 99%. These findings provide valuable insights for designing advanced organic semiconductors and fluorescent materials with tunable properties, based on the BTBT core. [ABSTRACT FROM AUTHOR]

Berberine (BBR), as a natural isoquinoline alkaloid, has demonstrated various pharmacological activities, and is widely applied in the treatment of diseases. The quantitative analysis of BBR is important for pharmacological studies and clinical applications. In this work, utilizing the specific interaction between BBR and triplex DNA, a sensitive and selective fluorescent detecting method was established with DNA-templated silver nanoclusters (DNA-AgNCs). After binding with the triplex structure in the template of DNA-AgNCs, BBR quenched the fluorescence of DNA-AgNCs and formed BBR-triplex complex with yellow–green fluorescence. The ratiometric fluorescence signal showed a linear relationship with BBR concentration in a range from 10 nM to 1000 nM, with a detection limit of 10 nM. Our method exhibited excellent sensitivity and selectivity, and was further applied in BBR detection in real samples. [ABSTRACT FROM AUTHOR]

Single-crystalline layered oxide materials for lithium-ion batteries are featured by their excellent capacity retention over their polycrystalline counterparts, making them sought-after cathode candidates. Their capacity degradation, however, becomes more severe under high-voltage cycling, hindering many high-energy applications. It has long been speculated that the interplay among composition heterogeneity, lattice deformation, and redox stratification could be a driving force for the performance decay. The underlying mechanism, however, is not well-understood. In this study, we use X-ray microscopy to systematically examine single-crystalline NMC particles at the mesoscale. This technique allows us to capture detailed signals of diffraction, spectroscopy, and fluorescence, offering spatially resolved multimodal insights. Focusing on early high-voltage charging cycles, we uncover heterogeneities in valence states and lattice structures that are inherent rather than caused by electrochemical abuse. These heterogeneities are closely associated with compositional variations within individual particles. Our findings provide useful insights for refining material synthesis and processing for enhanced battery longevity and efficiency. [ABSTRACT FROM AUTHOR]

The pH‐dependent UV/Vis absorption and fluorescence of several analogs of the marine natural product ageladine A were investigated. Besides ageladine A itself, its BF2 complex and the corresponding debrominated analogs were included, as were the chloro analog of the debromoageladine‐BF2 complex, an imidazolone analog, and a triazole derivative, which lack the free amino group. Importantly, the pH‐dependence of the fluorescence of the chloro analog closely resembles that of the natural product ageladine A, but with about 25‐fold higher fluorescence intensity and a maximum between pH 3 and 6. The imidazolone derivative behaves in a complementary manner and shows fluorescence only above pH 6, but with less intensity than ageladine A. The calculated Stokes shifts agree well with the experiment, which underlines the accuracy of the DFT calculation method (ωB97XD/TApr‐cc‐pVDZ, PCM). The conformational fixation of arylated imidazo[4,5‐c]pyridines by BF2 units seems to be promising with regard to the development of novel, pH‐dependent fluorescent probes. [ABSTRACT FROM AUTHOR]

Heterogeneity in the fluorescence of carbon dots (CDs) has been hard to figure out so far. This could potentially be related to structural factors, size or intermediate fluorophores, especially when employing the bottom‐up synthesis. Herein, we unveil the origin of fluorescence and spectral heterogeneity of CDs using a simple dynamic method. This work reports the room light‐excited green fluorescence and dual‐emissive N‐doped CDs synthesized using a hydrothermal method. Studies were carried out considering the factors of fluorescence phenomena, such as excitation‐independent emission, fluorescent impurities, aggregation and solvation dynamics. The new steady‐state, Excitation‐resolved area‐normalized emission spectroscopy (ERANES) and ensemble measurements, including time‐resolved studies reveal that a heterogeneous environment exists in the ground state. Eventually, the results show the existence of core, edge and surface states in the CDs. Additionally, the fluorescence characteristics depend on the structural functionalization that occurs in both the intrinsic and extrinsic states of the CDs and it is proven that this does not violate the Kasha‐Vavilov rule. Although a highly purified material could still exhibit heterogeneity due to the ensemble emissive states and structural variations. Our results provide insights into the enduring debates about fluorescence and a deeper understanding of the structure‐ property relationship of CDs. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to compare geographic atrophy (GA) area semi-automatic measurement using fundus autofluorescence (FAF) versus optical coherence tomography (OCT) annotation with the cRORA (complete retinal pigment epithelium and outer retinal atrophy) criteria. Methods: GA findings on FAF and OCT were semi-automatically annotated at a single time point in 36 pairs of FAF and OCT scans obtained from 36 eyes in 24 patients with dry age-related macular degeneration (AMD). The GA area, focality, perimeter, circularity, minimum and maximum Feret diameter, and minimum distance from the center were compared between FAF and OCT annotations. Results: The total GA area measured on OCT was 4.74 ± 3.80 mm2. In contrast, the total GA measured on FAF was 13.47 ± 8.64 mm2 (p < 0.0001), with a mean difference of 8.72 ± 6.35 mm2. Multivariate regression analysis revealed a significant correlation between the difference in area between OCT and FAF and the total baseline lesion perimeter and maximal lesion diameter measured on OCT (adjusted r2: 0.52; p < 0.0001) and the total baseline lesion area measured on FAF (adjusted r2: 0.83; p < 0.0001). Conclusions: We report that the GA area measured on FAF differs significantly from the GA area measured on OCT. Further research is warranted in order to determine the clinical relevance of these findings. [ABSTRACT FROM AUTHOR]

Donor‐specific HLA antibody (DSA) has been recognised as an independent risk factor for graft failure in patients undergoing haploidentical haematopoietic stem cell transplantation (HID HSCT). Therapeutic plasma exchange (TPE), as a first‐line strategy for DSA desensitisation, can promptly reduce serum DSA levels. This study aimed to investigate DSA characteristics and identify a biomarker predicting the efficacy of DSA desensitisation in patients proceeding to HID HSCT. We retrospectively enrolled 32 patients with DSA from April 2021 to January 2024, and analysed the mean fluorescence intensity (MFI) value of DSA at the different time points of desensitisation treatment. Compared with baseline DSA level before TPE, the median MFI of HLA class I DSA was reduced from 8178.6 to 795.3 (p < 0.001), and HLA class II DSA decreased from 6210.9 to 808.8 (p < 0.001) after TPE. The DSA level in 1:16 diluted pre‐TPE serum correlated well with DSA value in post‐TPE serum (class I, r = 0.85, p < 0.0001; class II, r = 0.94, p < 0.0001), predicting TPE efficacy in 84.4% of patients. Based on the degree of DSA reduction after TPE, patients were divided into complete responders (decreased by >70%), partial responders (decreased by 30 to 70%) and non‐responders (decreased by <30%) and the percentages were 43.8%, 25% and 31.2%, respectively. Non‐responders receiving aggressive immunotherapy had longer overall survival compared to those receiving standard strategies (p < 0.05). The 1:16 diluted pre‐TPE serum may predict the efficacy of TPE and allow for more rational immunotherapy strategy for patients with DSA proceeding to HID HSCT. [ABSTRACT FROM AUTHOR]

Synthesis and photophysical properties of a fluorescent probe HBD is described. Probe upon interaction with metal ions, anions and nucleoside pyrophosphates (NPPs) showed fluorescence quenching with Cu2+ due to chelation enhanced quenching effect (CHEQ). Moreover, interaction of ensemble HBD.Cu2+ with anions and NPPs showed fluorescence "turn‐On" response with ATP selectively. "On‐Off‐On" responses observed with Cu2+ and ATP is attributed to an interplay between ESIPT and TICT processes. Cyclic voltammogram of probe exhibited quasi‐reversible redox behaviour with three oxidation and two reduction potentials and the change in band gaps of probe suggested the interaction with Cu2+ and ATP. The 2 : 1 and 1 : 1 binding stoichiometry for an interaction between probe and Cu2+ (LOD, 62 nM) and ensemble, HBD.Cu2+ with ATP (LOD, 0.4 μM) respectively are realised by Job's plot and HRMS data. Cell imaging studies carried out to detect Cu2+ and ATP in HeLa cells. Also, the output emission observed with Cu2+ and ATP is utilized to construct an implication (IMP) logic gate. Test paper strips showed naked‐eye visible color responses to detect Cu2+ and ATP. In real water samples probe successfully detected copper (0.03 μM) between 5–6.5 ppb level (ICP‐MS method). [ABSTRACT FROM AUTHOR]

A strained triple nanohoop with a shared central benzene unit is synthesized using a threefold intramolecular ring‐closing approach. Among the five possible constitutional isomers, the isomer with the highest D3h symmetry is isolated, the structure of which contains three nanohoop blades and a central hexaphenylbenzene unit. The structure is elucidated using NMR spectroscopy and mass spectrometry. The optical and electrochemical properties are investigated, revealing a moderate fluorescence quantum yield of 40 %. A water‐soluble nanomaterial is prepared using a nanoparticle encapsulation method, and a fluorescence quantum yield of 10 % is retained, which demonstrates the potential of the nanomaterial in biological systems. [ABSTRACT FROM AUTHOR]

Simple Summary: Indocyanine green (ICG) is a dye that helps surgeons see the blood supply to tissues. In this study, (MIRRORS ICG) researchers wanted to see if this dye could help find cancer in women with advanced ovarian cancer undergoing robotic surgery after chemotherapy. After injecting ICG, a special camera was used to look at the whole abdomen and pelvic area. In this study, 102 tissue samples were taken to see if ICG helped identify cancerous tissue. The results showed that ICG correctly identified cancer in 91.1% of cases but had a low specificity of 13.0%, meaning it often falsely indicated cancer. This technique did not significantly help in detecting cancer in patients with widespread disease, but it showed some potential in those who had responded well to chemotherapy and had few remaining cancer spots. Molecular imaging with targeted dyes could enhance precision surgery in the future. Indocyanine green (ICG) is a fluorescent dye used for sentinel lymph node assessment and the assessment of perfusion in skin flaps and bowel anastomoses. ICG binds serum proteins and behaves as a macromolecule in the circulation. Tumour tissue has increased vascular permeability and reduced drainage, causing macromolecules to accumulate within it. MIRRORS ICG is designed to determine whether indocyanine green (ICG) helped identify metastatic deposits in women undergoing robotic interval cytoreductive surgery for advanced-stage (3c+) ovarian cancer. Peritoneal surfaces of the abdominal and pelvic cavity were inspected under white light and near-infrared light (da Vinci Si and Xi Firefly Fluorescence imaging, Intuitive Surgical Inc.) following intravenous injection of 20 mg ICG in sterile water. Visibly abnormal areas were excised and sent to histopathology, noting IGC positivity. In total, 102 biopsies were assessed using ICG. Intravenous ICG assessment following neoadjuvant chemotherapy had a sensitivity of 91.1% (95% CI [82.6–96.4%]), a specificity of 13.0% (95% CI [2.8–33.6%]), a positive predictive value of 78.3% (95% CI [68.4–86.2%]), and a negative predictive value of 30.0% (95% CI [6.7–65.2%]) False-positive samples were seen in 9/20 patients. Psammoma bodies were noted in the histopathology reports of seven of nine of these patients with false-positive results, indicating that a tumour had been present (chemotherapy-treated disease). This study demonstrates the appearance of metastatic peritoneal deposits during robotic cytoreductive surgery following the intravenous administration of ICG in women who have undergone neoadjuvant chemotherapy for stage 3c+ advanced ovarian cancer. A perfusion assessment using indocyanine green (ICG) peritoneal angiography during robotic interval cytoreductive surgery for advanced ovarian cancer did not clinically improve metastatic disease identification in patients with high-volume disease. The use of ICG in patients with excellent response to chemotherapy where few tumour deposits remained shows some promise. The potential of molecular imaging to enhance precision surgery and improve disease identification using the robotic platform is a novel avenue for future research. [ABSTRACT FROM AUTHOR]

Two L-lysine-derived salicylidene ligands have been synthesized under ultrasound irradiations and characterized by several spectroscopic techniques. Both ligands exhibited a blue fluorescence emission in ethanolic solutions. (S, E)-3-Amino-7-((2-hydroxybenzylidene) amino) heptanoic acid (A) and (S, E)-3-amino-7-((4-chloro-2-hydroxybenzylidene) amino) heptanoic acid (B) showed a turn-off sensing of Cu2+ and Co2+ cations, respectively, over several tested transition metal cations such as Fe2+, Zn2+, Cr3+, Co2+, Ni2+ and Cu2+ in aqueous media. The ability of both tested L-lysine-derived ligands (A) and (B) to distinguish Cu2+ and CO2+, respectively, has been verified by optical studies, showing new absorption bands around 304 and 391 nm for (A)-Cu2+ and a new band around 455 nm for (B)-Co2+ along with the disappearance of the original bands supporting thereby the noticed Turn–Off results. [ABSTRACT FROM AUTHOR]

Accurate tumor localization and resection margin acquisition are essential in gastric cancer surgery. Preoperative placement of marking clips in laparoscopic gastrectomy as well as intraoperative gastroscopy can be used for gastric cancer surgery. However, these procedures are not available at all institutions. We conducted a prospective clinical trial to investigate the diagnostic performance of near-infrared fluorescent clips (ZEOCLIP FS) in laparoscopic gastrectomy. Patients with gastric cancer or neuroendocrine tumor in whom laparoscopic distal, pylorus-preserving, or proximal gastrectomy was planned were enrolled (n = 20) in this study. Fluorescent clips were placed proximal and/or distal to the tumor via gastroscopy on the day before surgery. During surgery, the clips were detected using a fluorescent laparoscope, and suturing was performed where fluorescence was detected. The clip locations were then confirmed via gastroscopy, and the stomach was transected. The primary endpoint was the detection rate of the marking clips using fluorescence, and the secondary endpoints were complications and distance between the clips and stitches. Among the 20 patients enrolled, distal and pylorus-preserving gastrectomies were performed in 18 and 2 patients, respectively. All clips were detected in 15 patients, indicating a detection rate of 75.0% (90% confidence interval: 54.4%-89.6%). Furthermore, no complications related to the clips were observed. The median distance between the clips and stitches was 5 (range, 0–10) mm. We report the feasibility and safety of preoperative placement and intraoperative detection of near-infrared fluorescent marking clips in laparoscopic gastrectomy. • This study analyzed diagnostic performance of fluorescent marking clips in laparoscopic gastrectomy. • The detection rate of the clips under fluorescent observation was 75.0%. • Placement and detection of the fluorescent clips in laparoscopic gastrectomy are feasible and safe. [ABSTRACT FROM AUTHOR]

A new method using fluorescence was developed to detect Hg2+ ions in water. This method relied on the reaction between NH2‐MIL‐53(Al) and 5‐bromo‐2‐hydroxyacetophenone. The method was carefully fine‐tuned for optimal reaction conditions and analytical parameters like pH levels, nanosensor quantity, and detection limits. It showed great linearity in detecting Hg2+ ions in the range of 0.0–3.0 ppm (0.0–1.50 × 10−5 M), with a very low detection limit of 1.65 × 10−2 ppm (8.23 × 10−8 M). We tested how well the method can distinguish between different substances by investigating whether other common substances in water samples would interfere. The results were positive, as the presence of these substances did not significantly affect the accuracy of detecting Hg2+ ions, confirming the method's reliability. In order to confirm its dependability, we conducted a quantitative test to detect Hg2+ ions in water samples. The recovery rates obtained ranged from 97.16% to 103.2%, demonstrating the method's precision and accuracy. A comparison with inductively coupled plasma optical emission spectrometry (ICP‐OES), a well‐known method for analyzing trace metals, produced similar results, further instilling confidence in the 5Br2HA = N‐Al‐MOF nanosensor that was developed. In general, this research emphasizes the exciting potential of the new nanosensor in detecting Hg2+ ions in various water and cosmetic samples. It provides a strong and dependable alternative to traditional detection methods. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Construction of helicenes by inducing heteroatoms has regarded as an effective strategy to enhance the chiroptical properties. We report a facile synthesis of a multiple helicene based on four indoles with two electron‐rich NBN‐coved edges. The structure of the NBN‐coved multiple helicene was confirmed by single‐crystal X‐ray diffraction analysis, revealing a twisted double [5]helicene motif with a saddle‐shaped skeleton. This NBN‐coved helicene showed strong green fluorescence with good photoluminescence quantum yield. Both theoretical calculations and experimental investigation have been exploited to probe the impact of electron‐rich NBN units on aromaticity and photophysical properties of the helicene. [ABSTRACT FROM AUTHOR]

A multi-stimuli responsive fluorophore, named NBDNI, was developed by constructing a 1,8-naphthalimide derivative in which a rotatable electron-donating N,N-dimethylaniline group attached to its 4-position. This molecular structure endowed NBDNI with aggregate-induced emission (AIE) and twisted intramolecular charge transfer (TICT) properties, enabling remarkable fluorescence changes in response to multiple external stimuli: (i) sensitivity to polarity in various solvent systems and polymer matrix; (ii) significant fluorescence response and excellent linearity towards temperature changes in solution; (iii) distinct switch of fluorescence color upon acid and base treatments; (iv) reversible mechanochromism behavior in the solid state. Moreover, the mechanisms underlying the aforementioned stimuli-responsive phenomena have been proposed based on comprehensive systematic measurements. Furthermore, preliminary applications such as fluorescence thermometry and acid/base test paper have been demonstrated. This research will bring about new opportunities for the development of novel stimuli-responsive luminescent materials. [ABSTRACT FROM AUTHOR]

This study examined the effects of low-temperature heat treatment on the characteristics of the rubies from Mong Hsu, Myanmar. Five ruby samples were heated to 400, 600, 900 and 1200 °C for different durations, respectively. Before and after each heating step, a visual examination was conducted with a gem microscope under different illumination conditions. Various spectral analyses such as UV-Vis, FTIR, Raman and PL were also used to examine the effect of heating on the ruby samples. The low-temperature heat treatment enhanced the ruby samples by causing the dark blue core to partially or completely fade away. It then increased the overall light transmittance and enhanced the fluorescence peak around 694 nm but did not improve the red hue of the samples. Two major changes were found in the experiments. One was the dark blue core of the samples that faded as the heating temperature increased. They were verified by the spectra to be the variation in the intervalence charge transfer between Fe2+ and Ti4+. The variation in the intervalence charge transfer of Mong Hsu ruby was not noticeable before heating to 900 °C but changed dramatically when heated to 1200 °C. The other was the shift of the FTIR peak, which is caused by decomposition of minerals due to heating. An FTIR 630 cm−1 peak proved to be sensitive to the low-temperature heating and might be helpful for detecting low-temperature treatment. [ABSTRACT FROM AUTHOR]

Solid‐state lasers based on mode‐locked technology are widely studied for their strong ability of average or peak power scaling and wide wavelength coverage. However, it usually takes a long time and a lot of effort to manually align an ultrafast solid‐state laser to achieve laser emission and stable mode‐locking. Here, an approach based on intelligent human‐like algorithms is proposed for aligning a solid‐state ultrafast laser system. The intelligent system is based on multi‐algorithm fusion and can fully simulate the process of observation, analysis, decision, and action of an experienced experimenter in the adjustment of the laser alignment and mode‐locking. The intelligent adjustment starts from the state of no laser emission, adopts the neural network, the modified augmented random search (ARS) algorithm, random search, and sliding window strategy, and takes the fluorescence and speckle patterns as indications to realize the laser emission and stable mode‐locking automatically. Several validation experiments are conducted using this intelligent system, and the stable mode‐locked pulses can be achieved within 40 s. This technology provides an efficient solution to the ultrafast solid‐state laser that requires full automatic laser emitting and stable mode‐locking for the first time. [ABSTRACT FROM AUTHOR]

Melanin is a crucial pigment in melanomagenesis. Its fluorescence in human tissue is exceedingly weak but can be detected through advanced laser spectroscopy techniques. The spectral profile of melanin fluorescence distinctively varies among melanocytes, nevomelanocytes, and melanoma cells, with melanoma cells exhibiting a notably "red" fluorescence spectrum. This characteristic enables the diagnosis of melanoma both in vivo and in histological samples. Neuromelanin, a brain pigment akin to melanin, shares similar fluorescence properties. Its fluorescence can also be quantified with high spectral resolution using the same laser spectroscopic methods. Documented fluorescence spectra of neuromelanin in histological samples from the substantia nigra substantiate these findings. Our research reveals that the spectral behavior of neuromelanin fluorescence mirrors that of melanin in melanomas. This indicates that the typical red fluorescence is likely influenced by the microenvironment around (neuro)melanin, rather than by direct pigment interactions. Our ongoing studies aim to further explore this distinctive "red" fluorescence. We have observed this red fluorescence spectrum in post-mortem measurements of melanin in benign nevus. The characteristic red spectrum is also evident here (unlike the benign nevus in vivo), suggesting that hypoxia may contribute to this phenomenon. Given the central role of hypoxia in both melanoma development and treatment, as well as in fundamental Parkinson's disease mechanisms, this study discusses strategies aimed at reinforcing the hypothesis that red fluorescence from (neuro)melanin serves as an indicator of hypoxia. [ABSTRACT FROM AUTHOR]

Leveraging the fluorescence enhancement effect of the G-triplex (G3)/thioflavin T (ThT) catalyzed by the adjacent double-stranded DNA positioned at the 5′ terminus of the G3, the G3-specific oligonucleotide (G3MB6) was utilized to facilitate the rapid detection of mercury (Hg(II)) through thymine–Hg(II)–thymine (T-Hg(II)-T) interactions. G3MB6 adopted a hairpin structure in which partially complementary strands could be disrupted with the presence of Hg(II). It prompted the formation of double-stranded DNA by T-Hg(II)-T, inducing the unbound single strand of G3MB6 to spontaneously form a parallel G3 structure, producing a solid fluorescence signal by ThT. Conversely, fluorescence was absent without Hg(II), since no double strand and formation of G3 occurred. The fluorescence intensity of G3MB6 exhibited a positive correlation with Hg(II) concentrations from 17.72 to 300 nM (R2 = 0.9954), boasting a notably low quality of limitation (LOQ) of 17.72 nM. Additionally, it demonstrated remarkable selectivity for detecting Hg(II). Upon application to detect Hg(II) in milk samples, the recovery rates went from 100.3% to 103.2%. [ABSTRACT FROM AUTHOR]

Objectives: The present trial’s aim was to compare the remineralization potential of self-assembling peptide P11-4 combined with fluoride to that of fluoride varnish. Materials and methods: Twenty-eight participants with 58 incipient carious lesions were enrolled in the present trial. Participants were randomly divided into two groups with 14 participants and 29 incipient lesions in each group. Patients were assigned either to self-assembling peptide combined with fluoride (Curodont Repair Fluoride Plus™) or sodium fluoride varnish (NaF, Bifluorid 10) groups. Both agents were applied according to the manufacturer’s instructions on non-cavitated incipient carious lesions. Lesions were assessed by two calibrated and blinded assessors at baseline, and after one-, three- and six-months using a laser fluorescence device (DIAGNOdent). Results: Although laser fluorescence scores significantly improved in both groups over time (p < 0.05), no notable differences were evident between both groups at one-month (p > 0.05). Yet, at three- and six-months statistically lower laser fluorescence readings were evident in the self-assembling peptide combined with fluoride group in comparison to the fluoride alone group (p < 0.05). There was 60% less risk for caries progression for Curodont Repair Fluoride Plus™ when compared to NaF varnish after six months. Self-assembling peptide combined with fluoride was able to change 65.5% of non-cavitated carious lesions from DIAGNOdent score 3 (11–20) to score 1 (0–4). Fluoride varnish was able to change 13.8% of the lesions from score 3 to score 1 after six months. Conclusions: The self-assembling peptide combined with fluoride varnish showed higher remineralization potential than fluoride varnish alone for incipient carious lesions over a six-months follow up. Clinical relevance: The combination of self-assembling peptide P11-4 and fluoride could offer a new tool in managing incipient carious lesions. [ABSTRACT FROM AUTHOR]

A transient fluorescence spectroscopy system based on time-correlated single photon counting (TCSPC) technology was constructed. Time-resolved fluorescence spectra of pure, modified and fresh milk were obtained using this system. A method for differentiating these dairy products was established by principal component analysis (PCA). The measured time-resolved fluorescence spectra of the dairy products were directly substituted into the principal component analysis model without fitting. The results showed that the two largest principal components, PC1 and PC2, had variance contribution values of 48.18% and 32.1%, respectively. The results were plotted as a two-dimensional graph of PC1 × PC2. The results showed that the coordinates of the dairy products were clearly distinguished in the two-dimensional plot, with pure milk in the fourth quadrant, modified milk in the second and third quadrants, and fresh milk in the first quadrant. It is inferred that the time-resolved fluorescence spectra were changed due to the different heat treatment of the dairy products. Compared with fluorescence spectroscopy, time-resolved fluorescence spectroscopy is less susceptible to instrumental variation. Data from different instruments can be compared. The developed method does not require any processing and fitting of fluorescence lifetimes to milk, which has the advantages of easy identification, simple operation, and short identification time. [ABSTRACT FROM AUTHOR]

In this investigation, the far-field scattering of luminescent molecules doped inside a layer of the plasmonic metallic nanoshells with and without the presence of an external point-like electric charge based on the quasistatic approximation is theoretically developed. We study the fluorescence emission from three types of multilayered plasmonic nanoparticles with the spherical shape by evaluating the far-field scattering cross section. In other words, we investigate how the plasmonic nanoshells having a luminescent layer alters the fluorescence emission of active molecules. It is found that a frequency shift in the spectrum is achieved which is strongly sensitive to the geometry and size of the particle and also the tunability increases with the number of layers. This behavior is an important key advantage for the design of plasmonic devices. Also, the calculations show that when an electric charge is positioned near the plasmonic nanoshell, the number of resonance modes increases. The results demonstrate that the fluorescence emission of the luminescent layer is affected when an external point charge is placed next to the multilayer plasmonic nanoshell. [ABSTRACT FROM AUTHOR]

Formaldehyde, one of the simplest reactive carbonyl substances, is involved in many physiological and pathological processes in living organisms. There is a large amount of data showing that abnormal elevation of formaldehyde is associated with a variety of diseases in the body, such as neurodegenerative diseases, Alzheimer's disease, cardiovascular diseases and cancer, and is also a representative carcinogen, so monitoring formaldehyde is of great importance for disease diagnosis and treatment. In this review, In this paper, we summarize and classify the last ten years of probes for the detection of formaldehyde according to different reaction mechanisms and discuss the structures and applications of the probes. Finally, we briefly describe the challenges and possible solutions in this field. We believe that more new probes provide powerful tools to study the function of formaldehyde in living systems. [ABSTRACT FROM AUTHOR]