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Extra‐cerebral manifestations of Alzheimer's disease (AD) develop in the retina, which is, therefore, considered a “window to the brain”. Recent studies demonstrated the dysregulation of the endocannabinoid (eCB) system (ECS) in AD brain. Here, we explored the possible alterations of ECS and the onset of gliosis in the retina of AD‐like mice. Tg2576 (TG) mice overexpressing the amyloid precursor protein (APP) were used at the age of 12 months, when hippocampal β‐amyloid plaques had not been developed yet. Analysis of retinal gliosis showed a significant increase in the number of IBA1 (+) microglia cells in TG versus wild type (WT). Gliosis was not associated with retinal β‐amyloid plaques, evident retinal degenerative signatures, or excitotoxicity; instead, oxidative stress burden was observed as increased acrolein levels. Analysis of the ECS (receptors/metabolic enzymes) through western blotting (WB) revealed the up‐regulation of cannabinoid receptor 2 (CB2) and monoacylglycerol lipase (MAGL), the enzyme responsible for the degradation of 2‐arachidonoylglycerol (2‐AG), in TG retinas. Fluorescence intensity analysis of anti‐CB2 and anti‐MAGL immuno‐stained cryosections was consistent with WB, showing their up‐regulation throughout the retinal layers. No statistically significant differences were found for the other enzymes/receptors of the ECS under study. However, linear regression analysis for individual animals showed a significant correlation between CB2 and fatty acid amide hydrolase (FAAH), diacylglycerol lipase α/β (DAGLα/β), and APP; instead, a significant negative correlation was found between MAGL and APP. Finally, ultra‐performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) demonstrated a significant reduction of 2‐AG in TG retinas (~0.34 ng/mg) compared to WT (~1.70 ng/mg), while a trend toward increase was found for the other eCB anandamide (AEA). Overall, our data indicate that gliosis and ECS dysregulation—in particular of CB2, MAGL and 2‐AG—occur in the retina of AD‐like mice before retinal degeneration and development of hippocampal β‐amyloid plaques. [ABSTRACT FROM AUTHOR]

Light chain amyloidosis (AL), is classified as a plasma cell dyscrasia, whereby a mutant plasma cell multiplies uncontrollably and secretes enormous amounts of immunoglobulin‐free light chain (FLC) fragments. These FLCs undergo a process of misfolding and aggregation into amyloid fibrils, that can cause irreversible system‐wide damage. Current treatments that focus on depleting the underlying plasma cell clone are often poorly tolerated, particularly in patients with severe cardiac involvement, meaning patient prognosis is poor. An alternative treatment approach currently being explored is the inhibition of FLC aggregation by stabilisation of the native conformer. Here, we aimed to identify and characterise antibody fragments that target FLC domains and promote their stabilisation. Using phage‐display screening methods, we identified a variable heavy (VH) domain, termed VH1, targeted towards the FLC. Using differential scanning fluorimetry and surface plasmon resonance, VH1 was characterised to bind and kinetically stabilise an amyloidogenic FLC, whereby a > 5.5 °C increase in thermal stability was noted. This improved stability corresponded to the inhibition of fibril formation, where 10 : 1 LC : VH1 concentration reduced aggregation to baseline levels. X‐ray crystallographic structures of the LC : VH1 complex at atomic resolution revealed binding in a 1 : 1 ratio, mimicking the dimeric antigen binding sites of the native immunoglobulin molecule and the native LC homodimer. [ABSTRACT FROM AUTHOR]

SUMMARY As a result of extensive selection, two polyploid grass weeds, Hordeum glaucum (northern barley grass; 2n = 4x = 28) and Bromus diandrus (ripgut brome; 2n = 8x = 56), have evolved resistance to glyphosate, in Australia. Previous research suggested amplification of 5‐enolpyruvylshikimate‐3‐Phosphate synthase (EPSPS) gene confers resistance in these two weed species. The objective of this research was to investigate the genomic organization of the EPSPS gene in these two species through molecular cytogenetic analyses of fluorescence in situ hybridization (FISH) to understand possible mechanism of amplification of this gene. EPSPS copy number of H. glaucum and B. diandrus plants was estimated via quantitative polymerase chain reaction. The susceptible plants of both species had one copy of EPSPS, whereas the resistant plants of H. glaucum and B. diandrus had 14–17 and 16–32 copies, respectively. FISH analysis of glyphosate‐susceptible (Hg‐RWS) H. glaucum, revealed four faint signals of the EPSPS gene in two pairs of homologous chromosomes, at the telomeric region. The glyphosate‐resistant H. glaucum (Hg‐YP1) also showed amplification of EPSPS gene at telomeric regions in two pairs of homologous chromosomes, but the signals were brighter and appeared as cluster of EPSPS genes. Similarly, the glyphosate‐susceptible B. diandrus (Bd‐S) plants showed faint signals of EPSPS gene on two homologous chromosomes, at the telomeric position. However, samples of two glyphosate‐resistant, B. diandrus, Bd‐SA988 and Bd‐Vic showed much brighter hybridization signals of EPSPS gene, located at the telomere on two homologous chromosomes, suggesting an increase in EPSPS gene copies at this position. Overall, unequal crossover during meiosis may have triggered the initial EPSPS gene duplication sparking the evolution of glyphosate resistance. [ABSTRACT FROM AUTHOR]

The Chemical Communications journal, published by The Royal Society of Chemistry, features a variety of research articles on topics such as luminescent lanthanide metallopeptides, CO2 electrolysis, and supramolecular palladium complexes for cancer therapy. The journal covers a range of scientific discoveries in the field of chemistry, including studies on high-entropy alloy nanomaterials, asymmetric radical reactions, and novel nitrogen-doped porous carbon nanospheres for supercapacitors. The articles provide valuable insights into cutting-edge research in the chemical sciences, showcasing innovative approaches and applications in the field. [Extracted from the article]

A fluorescence method has been successfully constructed to accurately measure the D / L -Arb configuration content in optical isomers, and its application in ion detection has been expanded, which has greater sensitivity and universality than the circular dichroism (CD) method. It also promotes the study of the emission mechanism of nonconventional luminogens. [ABSTRACT FROM AUTHOR]

Background: New daily persistent headache (NDPH) is a rare primary headache disorder characterized by daily and persistent sudden onset headaches. Specific abnormalities in gray matter and white matter structure are associated with pain, but have not been well studied in NDPH. The objective of this work is to explore the fiber tracts and structural connectivity, which can help reveal unique gray and white matter structural abnormalities in NDPH. Methods: The regional radiomics similarity networks were calculated from T1 weighted (T1w) MRI to depict the gray matter structure. The fiber connectivity matrices weighted by diffusion metrics like fractional anisotropy (FA), mean diffusivity (MD) and radial diffusivity (RD) were built, meanwhile the fiber tracts were segmented by anatomically-guided superficial fiber segmentation (Anat-SFSeg) method to explore the white matter structure from diffusion MRI. The considerable different neuroimaging features between NDPH and healthy controls (HC) were extracted from the connectivity and tract-based analyses. Finally, decision tree regression was used to predict the clinical scores (i.e. pain intensity) from the above neuroimaging features. Results: T1w and diffusion MRI data were available in 51 participants after quality control: 22 patients with NDPH and 29 HCs. Significantly decreased morphological similarity was found between the right superior frontal gyrus and right hippocampus. The superficial white matter (SWM) showed significantly decreased FA in fiber tracts including the right superficial-frontal, left superficial-occipital, bilateral superficial-occipital-temporal (Sup-OT) and right superficial-temporal, meanwhile significant increased RD was found in the left Sup-OT. For the fiber connectivity, NDPH showed significantly decreased FA in the bilateral basal ganglion and temporal lobe, increased MD in the right frontal lobe, and increased RD in the right frontal lobe and left temporal-occipital lobe. Clinical scores could be predicted dominantly by the above significantly different neuroimaging features through decision tree regression. Conclusions: Our research indicates the structural abnormalities of SWM and the neural pathways projected between regions like right hippocampus and left caudate nucleus, along with morphological similarity changes between the right superior frontal gyrus and right hippocampus, constitute the pathological features of NDPH. The decision tree regression demonstrates correlations between these structural changes and clinical scores. [ABSTRACT FROM AUTHOR]

Stress in sea urchins leads to high mortality and economic losses in both the environment and aquaculture. The green sea urchin Strongylocentrotus droebachiensis has been documented emitting complex biofluorescence, yet how this responds to external stressors is unknown. Adult sea urchins (n = 210) were divided between control (n = 30) and experimental groups (n = 180), using three transport variables: out of water, in water at elevated temperatures, (warm-water) and in water at seawater temperature (cold-water). Hyperspectral imaging of external fluorescence and fluorospectrometric analysis on coelomic fluid was measured at five intervals (hour 0,3,6,9,12). External green emissions (∼580 nm) responded to all treatments, peaking at h9. External red emissions (∼680–730 nm) in the cold-water remained low until an h9 peak. The warm water increased emissions at each interval, peaking at h9. The out of water gradually increased, with the highest at h12. The coelomic fluid fluorescence (∼680 nm) was low to nonexistent except in warm-water, whose elevated levels suggest that fluorescent emissions are a measurable byproduct of internal adaptation(s) to stress. Early detection of fluorescent emissions (broken spines, lesions) may prevent economic losses. The observed link between fluorescence and the applied stressors provides a baseline for developing non-invasive technology for improving echinoderm welfare. [ABSTRACT FROM AUTHOR]

Background and Aims Thallium (Tl) is extremely toxic to all life forms and is an emerging pollutant. Plants in the Brassicaceae family, including edible crops, have an enhanced capacity for Tl accumulation, even from soils with low thallium concentration. The most extreme Tl hyperaccumulator is Biscutella laevigata , capable of attaining >32 000 μg Tl g−1 dry weight (DW) in its leaves. Methods Biscutella laevigata from a non-metallicolous accession (Feltre, Italy) and a metallicolous accession (Les Malines, France) were subjected to a dosing experiment in hydroponics (0, 5 and 30 μ m Tl), followed by synchrotron-based micro-X-ray fluorescence analysis to elucidate tissue- and cellular-level Tl distribution. Key Results Flow cytometric data on the two accessions showed that the Feltre accession has a genome size twice of that of the Les Malines accession (256 and 125 pg per 2 C , respectively), suggesting that they are phylogenetically distant populations. The Feltre accession did not accumulate Tl (125 μg Tl g−1 DW on average in leaves) at the 5 µ m Tl dose level, whereas the Les Malines accession had a mean of 1750 μg Tl g−1 DW, with peaks of 24 130 μg Tl g−1 DW, at the 30 µ m Tl dose level. At 30 µ m Tl, the non-metallicolous accession did not grow, and at 5 µ m Tl it showed reduced biomass compared with the metallicolous one. In the Les Malines accession, the synchrotron-based micro-X-ray fluorescence analysis revealed that Tl was localized in the vacuoles of epidermal cells, especially underneath trichomes and in trichome basal cells. Thallium also occurred in solid crystalline deposits (3–5 µm in size, ~40 wt% Tl) that were found mainly in foliar margins and under trichome bases. Conclusions Biscutella laevigata is an attractive model for studying Tl hypertolerance and hyperaccumulation on account of the extreme expression of this trait and its marked intraspecific variability. [ABSTRACT FROM AUTHOR]

Mercury is a pollutant that poses a considerable health risk. The concentration of mercury in scalp hair can be used to estimate past mercury exposure. Methods such as atomic absorption spectrophotometry and inductively coupled plasma‐based techniques have been used to determine the concentrations of trace elements in scalp hairs; however, these analytical methods have several limitations, including the need for expensive equipment, complex sample preparation, and large samples of more than 100 hairs. Therefore, simpler and more cost‐effective methods are required. X‐ray fluorescence (XRF) spectroscopy is a simple and fast analytical method. To improve the sensitivity, we applied a secondary target method to enhance the XRF excitation and reduce the background. In conventional secondary target methods, the primary x‐rays irradiate a secondary target of a pure substance, and the sample is then irradiated with the fluorescent x‐rays from the secondary target. We placed high‐purity Y₂O₃ powder, which served as the secondary target, behind the hair samples. The XRF intensities of trace elements such as mercury and zinc in the hair were enhanced by applying the secondary target behind the hair. [ABSTRACT FROM AUTHOR]

Near-infrared phosphor converted light-emitting diodes (NIR pc-LEDs), as a state-of-the-art type of NIR sources, are finding multifaceted applications, where phosphor is a crucial component. In hope to provide new choices for NIR lighting, we synthesized in this work the two series of Ruddlesden -Popper type layered perovskite phosphors of SrLa 2 Al 2- x O 7 : x Cr3+ (x = 0–0.02) and SrLa 2- y Gd y Al 1.984 O 7 :0.016Cr3+ (y = 0–2), followed by detailed structure and luminescence investigation. SrLa 2 Al 2- x O 7 : x Cr3+ was found to emit ∼700–800 nm NIR light under UV excitation and be able to maintain ∼54.3 % of its room temperature intensity at 423 K, which is remarkably higher than those (∼25–30 %@423 K) of the Mn4+ activated perovskite NIR phosphors. Luminescence regulation was achieved by substituting La3+ with Gd3+, and it was revealed that Gd3+ may act as a sensitizer to significantly enhance Cr3+ luminescence (∼346 % at 77 K) through Gd3+ → Cr3+ energy transfer, which was confirmed by spectral and fluorescence lifetime analysis. The observed spectral features and the influence of Gd3+ were rationalized by considering crystal structure, local coordination, and crystal field. Finally, an NIR pc-LED device showing strong ∼700–900 nm luminescence was fabricated to show potential application of the phosphor in night vision and plant lighting. [ABSTRACT FROM AUTHOR]

Benzonitrile derivatives (BDs) are very promising for applications in materials science, photonics, and optoelectronics due to their intriguing electronic and optical properties. This study comprehensively investigates BDs, aiming to uncover their fundamental characteristics and potential applications. Using advanced theoretical techniques like Gaussian software, it is gained unprecedented insights into the photoinduced isomerization phenomenon for all‐optical switching in these compounds. The theoretical framework clarifies molecular transition states and explores a range of properties, providing a comprehensive understanding of BDs. Empirical data on the emission properties of BDs, from fluorescence analyses in liquid solutions to light amplification in solid‐state PMMA thin films, complement the theoretical examinations. Notably, white light emission from a single benzonitrile compound is achieved, showcasing its potential for data transmission through Li‐Fi technology. Finally, the all‐optical switching phenomenon in BDs using 3rd order nonlinear optical effects is experimentally validated. This complementary and comprehensive study advances understanding of BDs and demonstrates their potential for practical applications in emerging photonic and optoelectronic technologies. [ABSTRACT FROM AUTHOR]

The use of proteins as targeting agents often requires their chemical modification for their efficient attachment to a given surface. However, no control over the protein integrity and functionality has been demonstrated to date. Chemical over‐modification causes the loss of the native structure of the protein and thus limits its targeting efficiency. To preserve structural integrity, a minimal modification strategy of proteins is developed while maintaining their functionality. Apolipoprotein A1 (ApoA1) and liposomes are utilized as a nanocarrier platform. Monitoring NHS ester chemistry by time‐of‐flight mass spectrometry experiments, the proposed functionalization route allows the effective chemical coupling of the minimally modified ApoA1 to the surface of the liposomes via a click chemistry reaction. The stability of the modified ApoA1 is ensured by analyzing the secondary structure by circular dichroism spectroscopy and the corresponding melting point by nano differential scanning fluorimetry. Furthermore, ApoA1 attachment to the liposomes is confirmed by flow cytometry experiments. The procedure presented in this study has the potential to be easily transferred to other proteins while introducing only minimally necessary chemical modifications to be covalently attached to different drug delivery platforms. This can help to improve their targeting efficiency for future biomedical applications. [ABSTRACT FROM AUTHOR]

Motorship wrecks on the seabed pose a serious threat to the marine environment due to oil leaking from their fuel tanks. Such substances can penetrate the sediments and enter the water. There is a need to analyse bottom water and seabed sediment samples for the content of toxic petroleum substances. Tests were undertaken on samples collected near ​​the site of the World War II shipwreck of the s/s "Stuttgart". The wreck is located in the Baltic Sea, in the Gulf of Gdańsk. To answer whether toxic hydrocarbons from wrecks enter the sea environment, a fluorometric analysis was carried out based on measurements of excitation-emission ultraviolet spectra for sediments and near-seabed water. The results of these analyses indicate the presence of oil substances in the sediments and the bottom water at some sampling points close to the wreck site. Studies have shown that the applied method of the so-called fluorometric indicator allows for determining the sites of water pollution with oil substances hidden in sediments. [ABSTRACT FROM AUTHOR]

Salinity stress is one of the most detrimental factors affecting crop production worldwide. Genetic engineering offers a promising approach for improving agronomic traits and enhancing stress tolerance. In a previous work, several potential candidate genes were identified in potato using large-scale functional yeast screening. In this work, we characterized one of the identified genes, an auxin-repressed protein 1 (ARP1), in transgenic Arabidopsis plants. ARP1 transgenic lines were subjected to salinity stress and compared with wild-type (WT) plants. Compared to WT plants, transgenic ARP1 lines showed significant improvements in morphological parameters, such as plant height, leaves per plant, root length, and fresh weight. Additionally, biochemical and physiological analyses revealed that the transgenic ARP1 lines exhibited improved stomatal conductance, reduced electrolyte leakage, increased proline and chlorophyll accumulation, significantly enhanced malondialdehyde accumulation, and antioxidant enzyme activity. Additionally, spectral analysis revealed that transgenic ARP1 lines had increased photosynthetic capacity compared to WT plants, as indicated by various biochemical parameters and pigment indicators. Transgenic ARP1 lines also showed improved photosystem (PSII) efficiency compared to WT plants, as demonstrated by detailed chlorophyll fluorescence analyses. Moreover, both ARP1 lines showed significantly higher expression levels of SOD, CAT, and APX than the WT plants under salt stress. The highest increase in relative expression was observed with SOD (3-fold increase) as compared to their respective WT in both ARP1 lines. We conclude that potato ARP1 is a promising candidate gene for the future development of salt-tolerant crops. [ABSTRACT FROM AUTHOR]

The myofibrillar protein (MP) of duck meat is prone to excessive oxidation during thermal processing, resulting in a decline in its overall quality. In this paper, the effect of shikimic acid on the oxidative structure of duck muscle fibrin was studied. The findings showed that, at a mass ratio of 1:50,000 (g/g) between shikimic acid and MP, the carbonyl content of MP was reduced by 74.20%, while the sulfhydryl content was increased by 73.56%. MP demonstrated the highest denaturation temperature, whereas its thermal absorption was the lowest. The percentage of α-helixes and β-sheets increased by 16.72% and 24.74%, respectively, while the percentage of irregular structures decreased by 56.23%. In addition, the surface hydrophobicity index of MP exhibited a significant decrease (p < 0.05), while there was a significant increase in its free radical-scavenging ability (p < 0.05). Molecular fluorescence spectrum analysis showed that shikimic acid could bind to MP, altering the internal environment of MP and enhancing its thermal stability. FTIR analysis showed that shikimic acid could enhance the distribution of protein particle sizes by reducing irregular structures, the proportion of β-rotation, and the degree of protein aggregation. It is hoped that this research can offer scientific support for improving meat processing technology. [ABSTRACT FROM AUTHOR]

Background and Aims: Avicennia marina, a pioneer recretohalophyte mangrove species living in intertidal wetlands, has high salinity tolerance. To understand the mechanism of salt adaptability, the seedlings of A. marina were treated with different salinities. We hypothesized that A. marina would demonstrate adaptive mechanisms at both physiological and molecular levels to tolerate tidal salinity through ion selectivity and chloride homeostasis. Methods: In this study, the combination of growth, chlorophyll fluorescence analysis, electron microscopy, electrophysiological and molecular approaches were employed to investigate the mechanism of salt adaptability of A. marina seedlings. Results: 400 mM NaCl promoted chloroplast development, and chlorophyll fluorescence Fv/Fm, Fv/Fo, and qP decreased with increasing NaCl concentration, while ETR remained stable. NaCl contributed to increased Na+ and Cl− content in roots, leaves and exudates of salt glands, while relative high Cl− was stored in the roots and more Na+ in the leaves. Flux measurements of Na+, Cl−, K+, H+, and NO3− in the leaf salt glands and the root tips treated with 0 and 400 mM NaCl indicated the presence of an ion selectivity that was suppressed by specific Na+/H+ antiporter inhibitor amiloride, PM H+-ATPase inhibitor vanadate, and Na+:K+:2Cl− cotransporter inhibitor bumetanide. Further analysis showed that the expressions of chloride transport-related homolog genes CLCc, CLCf, and CCC1 were significantly up-regulated, whereas CLCd was down-regulated under salt treatment. Conclusions: In conclusion, the chloride homeostasis regulated by salt ion secretion selectivity and transport-associated genes in leaf and root serves a crucial role in the salt tolerance of A. marina. [ABSTRACT FROM AUTHOR]

The Pinghu slope belt in the Xihu sag of the East China Sea Shelf Basin (ECSSB) is a crucial hydrocarbon production area in eastern China. However, due to the complex geological conditions, publications have lacked comprehensive research on the spatial-temporal coupling relationships of primary factors that impact hydrocarbon accumulation in the Pinghu slope belt. Furthermore, the hydrocarbon distribution patterns and the controlling factors across different study areas within the same slope belt are not yet fully understood. This study extensively utilized three-dimensional seismic data, well logging data, geochemical analysis, fluorescence analysis, and oil testing and production data to address these issues. Following a "stratification and differentiation" approach, the study identified seven distinct hydrocarbon migration and accumulation units (HMAU) in the Pinghu slope area based on the structural morphology characteristics, hydrocarbon source-reservoir-cap rock patterns, hydrocarbon migration pathways, and hydrocarbon supply range. Detailed analysis was conducted to examine the hydrocarbon distribution patterns and controlling factors within each migration and accumulation unit across different structural units, including high, medium, and low structural components. All data sources support a "southern-northern sub-area division, eastern-western sub-belt division, and variations in hydrocarbon accumulation" pattern in the Pinghu slope belt. The degree of hydrocarbon accumulation is controlled by the factors of structural morphology, hydrocarbon generation potential of source rocks, the spatial position of source slopes, fault sealing capacity, and sand body distribution. Furthermore, different coupling patterns of faults and sand bodies play a pivotal role in governing hydrocarbon enrichment systems across various migration and accumulation units. These observations indicate that three hydrocarbon accumulation patterns have been established within the slope belt, including near-source to far-source gentle slope with multiple hydrocarbon kitchens in the XP1-XP4 zones, near-source to middle-source gentle slope with dual-hydrocarbon kitchens in the XP5 zone, and near-source steep slope with a single hydrocarbon kitchen in the XP6-XP7 zones. These findings contribute to enhancing the theoretical system of hydrocarbon accumulation in the slope belt. [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]

A new nanodevice based on gold nanoparticles (AuNPs) capped with poly(diethylvinylphosphonate) (PDEVP) has been synthesized, showing interesting photophysical and thermoresponsive properties. The synthesis involves a properly designed Yttriocene catalyst coordinating the vinyl-lutidine (VL) initiator active in diethyl vinyl phosphonate polymerization. The unsaturated PDEVP chain ending was thioacetylated, deacetylated, and reacted with tetrachloroauric acid and sodium borohydride to form PDEVP-VL-capped AuNPs. The NMR, UV–Vis, and ESI-MS characterization of the metal nanoparticles confirmed the formation of the synthetic intermediates and the expected colloidal systems. AuNPs of subnanometric size were determined by WAXD and UV–Vis analysis. UV–Vis and fluorescence analysis confirmed the effective anchoring of the thiolated PDEVP to AuNPs. The formation of 50–200 nm globular structures was assessed by SEM and AFM microscopy in solid state and confirmed by DLS in aqueous dispersion. Hydrodynamic radius studies showed colloidal contraction with temperature, demonstrating thermoresponsive behavior. These properties suggest potential biomedical applications for the photoablation of malignant cells or controlled drug delivery induced by light or heat for the novel PDEVP-capped AuNP systems. [ABSTRACT FROM AUTHOR]

PDIA3 is a pleiotropic protein primarily located in the endoplasmic reticulum where it is involved in protein folding, catalyzing the formation, breakage, and rearrangement of disulfide bonds. PDIA3 is implicated in numerous pathologies such as cancer, inflammation, and neurodegeneration. Although punicalagin has been proven to be a highly promising PDIA3 inhibitor and can be used as target protein in glioblastoma, it does not have sufficient selectivity for PDIA3 and is a quite-large molecule. With the aim of finding punicalagin derivatives with a simplified structure, we selected punicalin, which lacks the hexahydroxy-diphenic acid moiety. Previous docking studies suggest that this part of the molecule is not involved in the binding with PDIA3. In this study we compared the ability of punicalin to bind and inhibit PDIA3 and PDIA1. Tryptophan fluorescence quenching and disulfide reductase activity (using both glutathione and insulin as substrates) were evaluated, demonstrating the ability of punicalin to bind and inhibit PDIA3 even to a lesser extent compared to punicalagin. On the other hand, punicalin showed a very low inhibition activity towards PDIA1, demonstrating a higher selectivity for PDIA3. Protein thermal shift assay evidenced that both proteins can be destabilized by punicalin as well as punicalagin, with PDIA3 much more sensitive. Additionally, punicalin showed a higher change in the thermal stability of PDIA3, with a shift up to 8 °C. This result could explain the presence of PDIA3 aggregates, evidenced by immunofluorescence analysis, that accumulate within treated cells and that are more evident in the presence of punicalin. The results here obtained show punicalin is able to bind both proteins but with a higher selectivity for PDIA3, suggesting the possibility of developing new molecules with a simplified structure that are still able to selectively bind and inhibit PDIA3. [ABSTRACT FROM AUTHOR]

Objective: Midpalatal expansion (MPE) is routinely employed to treat transverse maxillary arch deficiency. Neutrophils are indispensable for recruiting bone marrow stromal cells (BMSCs) at the initial stage of bone regeneration. This study aimed to explore whether neutrophils participate in MPE and how they function during bone formation under mechanical stretching. Materials and Methods: The presence and phenotype of neutrophils in the midpalatal suture during expansion were detected by flow cytometry and immunofluorescence staining. The possible mechanism of neutrophil recruitment and polarization was explored in vitro by exposing vascular endothelial cells (VECs) to cyclic tensile strain. Results: The number of neutrophils in the distracted suture peaked on Day 3, and N2‐type neutrophils significantly increased on Day 5 after force application. The depletion of circulatory neutrophils reduced bone volume by 43.6% after 7‐day expansion. The stretched VECs recruited neutrophils via a CXCR2 mechanism in vitro, which then promoted BMSC osteogenic differentiation through the VEGFA/VEGFR2 axis. Consistently, these neutrophils showed higher expression of canonical N2 phenotype genes, including CD206 and Arg1. Conclusions: These results suggested that neutrophils participated in early bone formation during MPE. Based on these findings, we propose that stretched VECs recruited and polarized neutrophils, which, in turn, induced BMSC osteogenic differentiation. [ABSTRACT FROM AUTHOR]

Promastigote Leishmania mexicana have a complex cell division cycle characterised by the ordered replication of several single-copy organelles, a prolonged S phase and rapid G2 and cytokinesis phases, accompanied by cell cycle stage-associated morphological changes. Here we exploit these morphological changes to develop a high-throughput and semi-automated imaging flow cytometry (IFC) pipeline to analyse the cell cycle in live L. mexicana. Firstly, we demonstrate that, unlike several other DNA stains, Vybrant™ DyeCycle™ Orange (DCO) is non-toxic and enables quantitative DNA imaging in live promastigotes. Secondly, by tagging the orphan spindle kinesin, KINF, with mNeonGreen, we describe KINF's cell cycle-dependent expression and localisation. Then, by combining manual gating of DCO DNA intensity profiles with automated masking and morphological measurements of parasite images, visual determination of the number of flagella per cell, and automated masking and analysis of mNG:KINF fluorescence, we provide a newly detailed description of L. mexicana promastigote cell cycle events that, for the first time, includes the durations of individual G2, mitosis and post-mitosis phases, and identifies G1 cells within the first 12 minutes of the new cell cycle. Our custom-developed masking and gating scheme allowed us to identify elusive G2 cells and to demonstrate that the CDK-inhibitor, flavopiridol, arrests cells in G2 phase, rather than mitosis, providing proof-of-principle of the utility of IFC for drug mechanism-of-action studies. Further, the high-throughput nature of IFC allowed the close examination of promastigote cytokinesis, revealing considerable flexibility in both the timing of cytokinesis initiation and the direction of furrowing, in contrast to the related kinetoplastid parasite, Trypanosoma brucei and many other cell types. Our new pipeline offers many advantages over traditional methods of cell cycle analysis such as fluorescence microscopy and flow cytometry and paves the way for novel high-throughput analysis of Leishmania cell division. [ABSTRACT FROM AUTHOR]

Purpose: Transfusion-dependent thalassemia (TDT) is associated with iron accumulation in the body and an increased tendency for thrombosis. With the increased life expectancy in these patients, the detection of neurocognitive complications has gained importance. This study investigates the microstructural changes in TDT patients using advanced diffusion MRI techniques and their relationship with laboratory parameters. Methods: The study included 14 TDT patients and 14 control subjects. Tract-based spatial statistics (TBSS) were used to examine differences in DTI parameters such as fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) in thalassemia patients using multi-shell DWI images. The mean kurtosis (MK) difference was investigated using diffusion kurtosis imaging. Fiber density (FD), fiber cross-section (FC), and fiber density and cross-section (FDC) differences were examined using fixel-based analysis. In the patient group, correlative tractography was used to investigate the relationship between DTI parameters and platelet (PLT) and ferritin levels. Results: Increase in RD and MD was observed, particularly in the white matter tracts of the corona radiata in patient group. Additionally, an increase in AD was detected in a limited area. Correlative tractography in thalasemia patients showed a positive correlation between increases in RD, MD, and AD with PLT and ferritin. Fixel-based analysis demonstrated a dispersed distribution in white matter fibers, with a more pronounced decrease in FD, FC, and FDC in the internal capsule. Conclusion: There is widespread involvement in the white matter and fiber tracts in thalassemia patients, which is highly correlated with thrombotic parameters. [ABSTRACT FROM AUTHOR]

The chlorophyll content of wheat was assessed using multispectral fluorescence imaging (MSFI). Ultraviolet (UV) light (365 nm)-induced fluorescence images at 440, 520, 690, and 740 nm, and visible light (460, and 610 nm)-induced fluorescence images at 690 and 740 nm were acquired while leaf chlorophyll content was measured using SPAD 520. The fluorescence images were processed after segmentation and channel extraction to calculate the parameters of each leaf based on fluorescence images (F u 440 , F u 520 , F u 690 , and F u 740) obtained by UV excitation, and fluorescence images (F u 440 , F u 520 , F u 690 , F u 740 , F b 690 , F b 740 , and F r 740) obtained by three excitations of 365 nm, 460 nm, and 610 nm light. 12 fluorescence ratio parameters under UV excitation and 26 fluorescence ratio parameters under three excitations were calculated. The correlation analysis revealed that the fluorescence parameters (F r 740 , F u 440 , F u 520 , F u 690 , F u 740 , F b 690 , F b 740 , F u 440 / F u 520 , F u 520 / F u 690 , and F u 740 / F r 740) showed a strong correlation with the chlorophyll content. These parameters have the potential to measure the chlorophyll content. Subsequently, stepwise regression analysis (SRA) was employed to screen 16 fluorescence parameters under UV excitation and 33 fluorescence parameters under three excitations, with the objective of identifying and eliminating redundant variables. Finally, four variables (F u 520 , F u 690 , F u 740 , and F u 690 / F u 520) under UV excitation and five variables (F r 740 , F u 520 , F b 740 , F u 740 / F u 690 , and F b 740 / F b 690) under three excitations were selected. The partial least squares regression (PLSR) model, constructed using three excitations, demonstrated enhanced performance with an R c 2 of 0.901, R v 2 of 0.904, root mean square error (RMSE) of calibration of 4.398, and RMSE of validation of 4.267. Multiexcitation fluorescence based on three excitations techniques has better performance for evaluating chlorophyll content. • Development of a portable three excitations multispectral fluorescence device. • Assessing the impact of single and three excitations on the detection of chlorophyll. • Establishment of a model for optimal detection of chlorophyll content in wheat. [ABSTRACT FROM AUTHOR]

The present study was conducted to optimize the preparation conditions of whey protein isolate-basil seed gum (WPI-BSG) conjugates resulting from the Maillard reaction in different weight ratios and reaction times. In addition, the stability of the emulsions stabilized by WPI-BSG conjugate was investigated. The covalent attachment of BSG to WPI was effectively confirmed by OPA method, FTIR and fluorescence spectrometry analysis. Results indicated that the maximum zeta potential (-79.83 ± 1.62 mV), emulsifying activity (29.33 ± 2.71 m2/g) and emulsifying stability (45.16 ± 5.14 min) of conjugates were obtained in the weight ratio of 1:2 (WPI to BSG) and reaction time of 2 h. It was also found that a longer heating time may lead to an increase in the browning intensity and a significant decrease in the emulsifying properties of the conjugates. Moreover, according to the results of particle size, zeta potential and creaming index, the emulsions stabilized by WPI-BSG conjugates were more stable than those stabilized by unheated WPI and WPI-BSG mixture. This study indicates that the Maillard reaction can successfully improve the emulsifying properties of WPI. Besides, WPI-BSG conjugates are able to increase physical stability of oil-in-water emulsions. [ABSTRACT FROM AUTHOR]

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SERK is a marker gene for early somatic embryogenesis. We screened and functionally verified a SERK-interacting protein to gain insights into tree-peony somatic embryogenesis. Using PoSERK as bait, we identified PorbcL (i.e., the large subunit of Rubisco) as a SERK-interacting protein from a yeast two-hybrid (Y2H) library of cDNA from developing tree-peony somatic embryos. The interaction between PorbcL and PoSERK was verified by Y2H and bimolecular fluorescence complementation analyses. PorbcL encodes a 586-amino-acid acidic non-secreted hydrophobic non-transmembrane protein that is mainly localized in the chloroplast and plasma membrane. PorbcL was highly expressed in tree-peony roots and flowers and was up-regulated during zygotic embryo development. PorbcL overexpression caused the up-regulation of PoSERK (encoding somatic embryogenesis receptor-like kinase), PoAGL15 (encoding agamous-like 15), and PoGPT1 (encoding glucose-6-phosphate translocator), while it caused the down-regulation of PoLEC1 (encoding leafy cotyledon 1) in tree-peony callus. PorbcL overexpression led to increased indole-3-acetic acid (IAA) content but decreasing contents of abscisic acid (ABA) and 6-benzyladenosine (BAPR). The changes in gene expression, high IAA levels, and increased ratio of IAA to ABA, BAPR, 1-Aminocyclopropanecarboxylic acid (ACC), 5-Deoxystrigol (5DS), and brassinolide (BL) promoted embryogenesis. These results provide a foundation for establishing a tree-peony embryogenic callus system. [ABSTRACT FROM AUTHOR]

Oily sludge (OS) has long been regarded as a hazardous waste, and improper disposal may lead to serious environmental concerns and human health risks. Despite various methods having been proposed and applied to the treatment of OS, the oil occurrence states and properties in sludge are rarely characterized, which may directly link to the selection and effectiveness of treatment methods. Here, confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD), gas chromatography (GC), and four components (SARA) analysis were utilized to characterize the changes in the oil occurrence states and compositions in OS samples before and after high-speed stirring (HSS) treatment. Our results show a substantial reduction in the oil concentration of OS after HSS treatment (from 32.98% to 1.65%), while SARA analysis reveals a similar oil composition before and after treatment, suggesting the broad applicability of HSS in removing oil and its insignificant selectivity towards various hydrocarbon components. This is further supported by the total petroleum hydrocarbon (TPH) analysis results, which show that the separated oil phase has a hydrocarbon composition similar to that of the original OS sample. The CLSM and fluorescence analysis suggest a homogeneous distribution of oil in the sludge, with relatively light components more concentrated in the pore systems between coarse mineral particles, whereas relatively heavy components tend to coexist with clay minerals. After HSS cleaning, both light and heavy components are removed to varying degrees, but light components are preferentially removed while heavy components tend to be retained in the sludge due to adsorption by clay minerals. This is consistent with TPH analysis, where a significant decrease in n-alkanes with lower carbon numbers (n-C14 to n-C20) was observed in the residual sample. Our findings demonstrate the dynamic response of oil occurrence states and compositions to the OS treatment process and highlight the importance of characterizing these fundamental properties prior to the selection of OS treatment methods. [ABSTRACT FROM AUTHOR]

Digitization in pathology and cytology labs is now widespread, a significant shift from a decade ago when few doctors used image processing tools. Despite unchanged scanning times due to excitation in fluorescent imaging, advancements in computing power and software have enabled more complex algorithms, yielding better-quality results. This study evaluates three nucleus segmentation algorithms for ploidy analysis using propidium iodide-stained digital WSI slides. Our goal was to improve segmentation accuracy to more closely match DNA histograms obtained via flow cytometry, with the ultimate aim of enhancing the calibration method we proposed in a previous study, which seeks to align image cytometry results with those from flow cytometry. We assessed these algorithms based on raw segmentation performance and DNA histogram similarity, using confusion-matrix-based metrics. Results indicate that modern algorithms perform better, with F1 scores exceeding 0.845, compared to our earlier solution's 0.807, and produce DNA histograms that more closely resemble those from the reference FCM method. [ABSTRACT FROM AUTHOR]

This article proposes a new method for determining the pathological state of a plant, based on a combination of the method for measuring the dynamics of photosystem II pigment fluorescence in the leaves of L. sativa plants and analyzing the resulting time series using bispectral analysis based on the wavelet transform. The article theoretically shows a possible mechanism for the appearance of a peak on the map of bispectrum indexes during nonlinear analog conversion of a physiological signal in a biological object. The phenomenon of increasing the degree of nonlinearity in the transmission of an external periodic signal in plant signaling systems has been experimentally demonstrated. [ABSTRACT FROM AUTHOR]

The effective binding of Rhodamine B (RhB), a xanthene dye, in solutions of amphiphilic sulfobetaine tetrapentylcalix[4]resorcinarene (C5-SB) at millimolar concentrations has been found. Using the FT-PGSE NMR technique, it was determined that the binding fraction (Pb) of RhB in the solution with a С(RhB)/С(С5-SB) ratio of 3.75 mM/5 mM was 0.57, whereas in a solution with an order of magnitude lower concentration, the Pb was only 0.12. This significant difference in interaction is also supported by 2D NOESY and 1H NMR spectra. Based on fluorimetry data, it appears that the influence of C5-SB on the spectral properties of RhB increases as the C5-SB/RhB molar ratio increases, but decreases as the concentration of C5-SB and RhB decreases. By comparing the spectral properties of RhB in the presence of C5-SB and tetrapentylcalix[4]resorcinarene with carboxylic (C5-COO−) and trimethylammonium (C5-N+Me3) peripheral groups, an assumption about the driving forces behind RhB, which led to an enhancement of the emission properties of the dye, was made. The study demonstrates the possibility of controlling the emissive properties of a xanthene dye by binding it to a supramolecular associate with amphiphilic calix [4] resorcinarene. [ABSTRACT FROM AUTHOR]

Simple Summary: Pigeon Newcastle disease is a severe infectious disease in pigeons, characterized by a high infection rate and mortality rate. Quick and accurate detection of this disease is crucial for preventing outbreaks. In our research, we developed a quick and accurate method to diagnose this disease using a combination of two advanced techniques: recombinase-aided amplification (RAA) and CRISPR/Cas12a. This method first amplifies parts of the virus's genetic material and then detects it, allowing for simple visualization using a lateral flow dipstick (LFD). Our tests showed that this method is very specific, meaning it does not react with other viruses, and it can detect very low amounts of the virus. When tested on real clinical samples, our new approach was performed, as well as the current gold standard test, quantitative real-time PCR. This new approach provides an important technical means for the rapid diagnosis of pigeon Newcastle disease onsite, enabling the timely prevention and control of Newcastle disease outbreaks. Pigeon Newcastle disease, caused by pigeon paramyxovirus type 1 (PPMV-1), is a significant infectious disease in pigeons that can result in substantial mortality and poses a severe threat to the pigeon industry. The rapid and accurate onsite diagnosis of pigeon disease is crucial for timely diagnosis and the implementation of effective prevention and control measures. In this study, we established a rapid detection method for PPMV-1 based on recombinase-aided amplification (RAA) and CRISPR/Cas12a. The RAA primers target the conserved regions of the L gene for preamplification in clinical nucleic acid samples, followed by CRISPR/Cas12a detection of the target gene. Visualization could be achieved by combination with a lateral flow dipstick (LFD). This method demonstrated high specificity, showing no cross-reactivity with non-PPMV-1 samples. The sensitivity of the method assessed by fluorescence analysis reached 100 copies/µL, and when it was combined with an LFD, the sensitivity was 103 copies/µL. The constructed RAA-CRISPR/Cas12a-LFD visual detection method was applied to clinical sample testing and was found to enable the rapid and accurate detection of swab samples and tissue specimens. Its sensitivity was consistent with the current gold standard, quantitative real-time PCR results. The RAA-CRISPR/Cas12a-LFD detection method we developed provides a novel approach for the rapid, simple, precise, and specific onsite diagnosis of pigeon Newcastle disease. [ABSTRACT FROM AUTHOR]

Singe‐turnover active chlorophyll a fluorometry (STAF) can be used to assess phytoplankton photosynthetic rates in terms of the photosystem II photochemical flux (JVPII, μmol e− m−3 s−1) instantaneously, autonomously, and at high resolution. While JVPII provides an upper limit to rates of phytoplankton primary productivity in units of carbon fixation, the conversion between these two rates is variable, limiting our ability to utilize high‐resolution JVPII data to monitor phytoplankton primary productivity. Simultaneous measurements of JVPII and 14C‐fixation help in understanding the factors controlling the variable ratio between the two rates. However, to date, methodological inconsistencies, including differences in incubation lengths and light quality, have greatly inhibited practical assessment of such electron to carbon ratios (Φe,C, mol e− mol C−1). We here present data from a range of dual‐incubation experiments in northeast Atlantic waters during which JVPII and 14C‐fixation were measured simultaneously on the same sample. Time‐course experiments show how Φe,C increases with incubation length, likely reflecting the transition from gross to net 14C‐fixation. Dual‐incubation experiments conducted under different light levels show a tendency for increased Φe,C under (super‐)saturating light. Finally, data from a diurnal experiment demonstrate how Φe,C increases over the course of a day, due to downregulation of 14C‐fixation. We provide a detailed description of our methodological approach, including a critical discussion of improvements to the calculation of JVPII implemented in the LabSTAF instrument used for active fluorescence measurements and the limitations of the well‐established 14C‐fixation approach. [ABSTRACT FROM AUTHOR]

Oil pollutants pose significant threats to marine and terrestrial ecosystems, necessitating the effective methods of oil species identification for the emergence responses of oil spill incidents. This study employs the excitation-emission matrix (EEM) fluorescence spectroscopy to capture and analyse the spectral characteristics of various oil species at different thicknesses. Some data augmentation techniques, including data smoothing and denoising, are introduced in this study to expand the dataset and enhance data quality. The methodology of transfer learning, which significantly reduces training time and improves model accuracy by sharing parameters, is adopted in this study. The enhancement of transfer learning method is examined using several typical deep learning networks. It is found that the implementation of transfer learning not only reduces the number of trainable parameters, but also improves identification accuracies by leveraging shared parameters, which makes it more efficient and accurate than building models from scratch. The proposed methodology enhances the capability of identifying petroleum pollutants using deep learning method and provides a new perspective on the advancement of oil spill monitoring technology. [ABSTRACT FROM AUTHOR]

The autofluorescence of erythrocyte porphyrins has emerged as a potential method for multi-cancer early detection (MCED). With this method's dependence on research-grade spectrofluorometers, significant improvements in instrumentation are necessary to translate its potential into clinical practice, as with any promising medical technology. To fill this gap, in this paper, we present an automated ratio porphyrin analyzer for cancer screening (ARPA-CS), a low-cost, portable, and automated instrument for MCED via the ratio fluorometry of porphyrins. The ARPA-CS aims to facilitate cancer screening in an inexpensive, rapid, non-invasive, and reasonably accurate manner for use in primary clinics or at point of care. To accomplish this, the ARPA-CS uses an ultraviolet-excited optical apparatus for ratio fluorometry that features two photodetectors for detection at 590 and 630 nm. Additionally, it incorporates a synchronous detector for the precision measurement of signals based on the Walsh-ordered Walsh–Hadamard transform (WHT)w and circular shift. To estimate its single-photodetector capability, we established a linear calibration curve for the ARBA-CS exceeding four orders of magnitude with a linearity of up to 0.992 and a low detection limit of 0.296 µg/mL for riboflavin. The ARPA-CS also exhibited excellent repeatability (0.21%) and stability (0.60%). Moreover, the ratio fluorometry of three serially diluted standard solutions of riboflavin yielded a ratio of 0.4, which agrees with that expected based on the known emission spectra of riboflavin. Additionally, the ratio fluorometry of the porphyrin solution yielded a ratio of 49.82, which was ascribed to the predominant concentration of protoporphyrin IX in the brown eggshells, as confirmed in several studies. This study validates this instrument for the ratio fluorometry of porphyrins as a biomarker for MCED. Nevertheless, large and well-designed clinical trials are necessary to further elaborate more on this matter. [ABSTRACT FROM AUTHOR]

Introduction: Plants in the environment are affected by various stresses, depending on the duration, intensity and growth stage of the plant, these stresses can reduce the process of photosynthesis and affect their growth and performance. However, traditional methods, even technically advanced ones such as the measurements of photosynthetic rates through the gas exchange (CO2, H2O, and O2), are timeconsuming and provide incomplete information on overall photosynthetic function. The development of knowledge in the field of chlorophyll fluorescence shows that this indicator has a high ability to study the photochemical efficiency of plant photosynthesis. Methods: For measuring the chlorophyll fluorescence in plants, leaves were dark-adapted for 30 minutes using leaf clips provided by the producer of handy-PEA. Measurements were performed on the middle of plant leaves following the standard protocol with illumination with continuous red light (peak in 650 nm wavelength; the spectral line half-width of 22 nm) provided by an array of three light-emitting diodes. The light pulse intensity used was 3500 μmol(photon).m-2s-1 and the duration of the light pulse was 1 s. The measured data were used for the calculation of the photosynthetic parameters using Biolyzer v. 3.06 HP software (a software provided with handy-PEA). Some of the parameters we discussed in this article due to their significance are FO = minimum fluorescence, FM = maximum fluorescence, FO/FM = The maximum quantum yield of basal non-photochemical energy losses, FV/FM = the maximum quantum efficiency of PSII, VJ = the relative variable fluorescence in step J after 2 ms, VI = the relative variable fluorescence in step I after 30 ms, N = the number of QA redox turnovers until FM, SM = the pool size of the electron acceptors on the reducing side of PSII, PIABS = performance index. Main Findings: The study of chlorophyll fluorescence can analyze with high detail the function and state of PSII reaction centres, and light-harvesting complexes. This index has a high correlation with other physiological parameters under different environmental stresses. In this article, an overview of the results of chlorophyll fluorescence analysis of crops underenvironmental stressesis given, and the key steps to stresses are presented. Under drought stress the ratio of active reaction centers in chlorophyll, primary photochemical reactions, and electron transfer are affected. By salinity stress in crops, the values of variable and, maximum fluorescence, the energy required to close the reaction centers, and the photosynthetic efficiency index decrease, while the time required to reach the maximum fluorescence increases. Under cold stress conditions, electron transfer flow per reactive centers, the quantum performance of photosystem II, and the efficiency of the water splitting complex in photosystem II decrease. Potassium affects light-dependent steps such as the size of receiving antennae and the electron connection of photosystem II reaction centers. The electron acceptor part of photosystem II is the main site of inhibition of photosynthetic electron transfer under the application of herbicides. Conclusion and Implications: This article has provided an overview of the information about the wide opportunities of using the chlorophyll fluorescence technique in plant science, agriculture and ecological research. The measured parameters of chlorophyll fluorescence are called the JIP-test and its analysis can be used to evaluate the effects of environmental stresses on plants. This technique requires more practical studies in biotic and even non-biotic stress conditions to provide reliable information to investigate the growth and development of plants, and this leads to an increase in our knowledge of the physiological basis of crop photosynthesis under stress conditions. [ABSTRACT FROM AUTHOR]

Hydroxamic acids represent a group of weak organic acids, both naturally occurring and synthetically derived, characterized by the general formula RC(= O)N(R'OH). In this study, we investigated the binding behavior of N-m-tolyl-4-chlorophenoxyaceto hydroxamic acid with calf thymus DNA (ct-DNA) and torula yeast RNA (t-RNA) through a combination of techniques including UV–visible spectroscopy, fluorescence emission analysis, viscometry, and computational simulations using AutoDock4 software. Our findings reveal that the mode of binding between the compound and the nucleic acids is consistent with intercalation. Competitive binding experiments demonstrated that the complex competes effectively with ethidium bromide (EB) for binding to ct-DNA/t-RNA, displacing EB from its binding sites. Additionally, the introduction of the compound into the DNA-EB system resulted in a quenching of fluorescence emission peaks. Analysis of absorption spectra indicated a red shift and hypochromic shift when the compound interacted with DNA, further supporting the intercalative binding mode. The calculated binding constant (Kb) value for the compound is 6.62 × 104 M−1 and 5.40 × 103 M−1 indicating a strong interaction with ct-DNA and t-RNA respectively. We determined the Stern–Volmer constants for ct-DNA and t-RNA as 9.96 × 104 M−1 and 8.13 × 105 M−1, respectively. The binding free energy values for ct-DNA/t-RNA were calculated to be − 3.741 × 107 and − 5.425 × 108 kcal/mol, respectively. Viscometric studies corroborated the UV results, showing a continuous increase in relative viscosity of ct-DNA/t-RNA solutions with the addition of the optimal hydroxamic acid concentration. Furthermore, we assessed the antioxidant activity of the compound using DPPH-radical scavenging and β-carotene linoleic acid assays. Gel electrophoresis results demonstrated the compound's remarkable efficacy in preventing DNA damage. Collectively, all experimental evidence supports the conclusion that N-m-tolyl-4-chlorophenoxyaceto hydroxamic acid binds to ct-DNA/t-RNA through an intercalative mechanism, which is consistent with our molecular docking simulations. [ABSTRACT FROM AUTHOR]

A new pyrenylbenzylidene–malononitrile (P2) was successfully synthesized via the Suzuki coupling reaction and Knoevenagel condensation using nano Cu as a catalyst. The compound P2 could detect hydrazine in 10% THF–PBS, pH 7.4, with a limit of detection (LOD) of 19.46 nM. Moreover, the P2–CA nanofibrous sheets were fabricated by combining compound P2 and cellulose acetate. The LOD of P2–CA nanofibrous sheets was found to be 0.02% w/v for hydrazine detection. The quantity of hydrazine vapor was recognized and quantified by analyzing fluorescence images acquired with a smartphone camera and a portable blacklight lamp that generates light with a wavelength of 365 nm using the ImageJ application. The concentration range of 0.025–1% w/v was accurately determined by employing ImageJ for fluorescence image analysis. Both compound P2 and P2–CA nanofibrous sheets are selective for hydrazine. Also, the mechanism of compound P2 and hydrazine was studied via1H NMR titration, FT-IR experiments and DFT calculations. In addition, the P2–CA nanofibrous sheet has the ability to detect hydrazine vapor in actual samples collected from the environment. Hence, the compound P2 and P2–CA nanofibrous sheets have significant promise as highly effective sensors for detecting hydrazine in water across many environments and industries. [ABSTRACT FROM AUTHOR]

Nanoporous carbon materials have attracted significant attention in the fields of sensing and catalysis owing to their unique reticular structure, designable composition and pore size. In this study, a multifunctional nanoporous carbon platform with the integration of thermal transformation, thermal activation and sonochemical exfoliation is proposed, which can be applied in electrochemical analysis, enzyme-like catalysis and fluorescence analysis. Using zeolitic imidazolate frameworks (ZIFs) as self-templates, N-doped nanoporous carbon was prepared via pyrolysis. Next, the as-prepared intermediate carbon material was transformed into four- to eight-layer carbon nanosheets via sonochemical exfoliation. The carbon nanosheets exhibited high electrical conductivity, electrochemical activity and dual enzyme-like catalytic properties owing to their high graphitization, large surface area, doped N and pore size. The resulting nanosheets can be used as precursors for the synthesis of quantum dots with green photoluminescence for fluorescence analysis. The multifunctional nanoporous carbon platform shows great potential for sensing. Furthermore, the fabrication procedure provides a new opportunity for devising carbon materials with special functions. [ABSTRACT FROM AUTHOR]

Objective: White matter hyperintensities (WMH) are the most common neuroimaging manifestation of cerebral small vessel disease, and is frequently observed in Alzheimer's disease (AD). This study aimed to investigate the relationship between WMH and cognition and to verify the mediation of grey matter atrophy in this relationship. Methods: The diffusion tensor imaging (DTI) technique analyses white matter fiber tract to assess white matter integrity. Voxel-based morphometry was applied to measure the grey matter volume (GMV). A linear regression model was applied to examine the associations between WMH and GMV, and mediation analyses was performed to determine the mediating role of regional GMV in the effect of WMH on cognitive function. Results: Compared to the HC group, AD group have 8 fiber tract fractional anisotropy (FA) decreased and 16 fiber tract mean diffusivity (MD) increased. Compared to AD without WMH, AD with high WMH had 9 fiber tracts FA decreased and 13 fiber tracts MD increased. High WMH volume was negatively correlated with GMV in the frontal--parietal region. Low WMH volume was also negatively correlated with GMV except for the three regions (right angular gyrus, right superior frontal gyrus and right middle/inferior parietal gyrus), where GMV was positively correlated. Mediation analysis showed that the association between WMH and executive function or episodic memory were mediated by GMV in the frontal--parietal region. Conclusion: Damage to white matter integrity was more severe in AD with WMH. Differential changes in DTI metrics may be caused by progressive myelin and axonal damage. There was a negative correlation between WMH and grey matter atrophy in frontal--parietal regions in a volume-dependent manner. This study indicates the correspondence between WMH volume and GMV in cognition, and GMV being a key modulator between WMH and cognition in AD. This result will contribute to understanding the progression of the disease process and applying targeted therapeutic intervention in the earlier stage to delay neurodegenerative changes in frontal--parietal regions to achieve better treatment outcomes and affordability. [ABSTRACT FROM AUTHOR]

Liquid-like protein condensates have recently attracted much attention due to their critical roles in biological phenomena. They typically show high fluidity and reversibility for exhibiting biological functions, while occasionally serving as sites for the formation of amyloid fibrils. To comprehend the properties of protein condensates that underlie biological function and pathogenesis, it is crucial to study them at the single-condensate level; however, this is currently challenging due to a lack of applicable methods. Here, we demonstrate that optical trapping is capable of inducing the formation of a single liquid-like condensate of α-synuclein in a spatiotemporally controlled manner. The irradiation of tightly focused near-infrared laser at an air/solution interface formed a condensate under conditions coexisting with polyethylene glycol. The fluorescent dye-labeled imaging showed that the optically induced condensate has a gradient of protein concentration from the center to the edge, suggesting that it is fabricated through optical pumping-up of the a-synuclein clusters and the expansion along the interface. Furthermore, Raman spectroscopy and thioflavin T fluorescence analysis revealed that continuous laser irradiation induces structural transition of protein molecules inside the condensate to β-sheet rich structure, ultimately leading to the condensate deformation and furthermore, the formation of amyloid fibrils. These observations indicate that optical trapping is a powerful technique for examining the microscopic mechanisms of condensate appearance and growth, and furthermore, subsequent aging leading to amyloid fibril formation. [ABSTRACT FROM AUTHOR]

This study describes the formation of single‐chain polymer dots (Pdots) via ultrasonic emulsification of nonionic donor‐acceptor‐donor type (D–A–D) alkoxy thiophene–benzobisthiadiazole‐based conjugated polymers (Poly BT) with amphiphilic cetyltrimethylammonium bromide (CTAB). The methodology yields Pdots with a high cationic surface charge (+56.5 mV ± 9.5) and average hydrodynamic radius of 12 nm. Optical characterization reveals that these Pdots emit near‐infrared (NIR) light at a maximum wavelength of 860 nm owing to their conjugated polymer backbone consisting of D–A–D monomers. Both colloidal and optical properties of these Pdots make them promising fluorescence emissive probes for bioimaging applications. The significant advantage of positively charged Pdots is demonstrated in diffusion‐limited mediums such as tissues, utilizing human epithelial breast adenocarcinoma, ATCC HTB‐22 (MCF‐7), human bone marrow neuroblastoma, ATCC CRL‐2266 (SH‐SY5Y), and rat adrenal gland pheochromocytoma, CRL‐1721 (PC‐12) tumor spheroid models. Fluorescence microscopy analysis of tumor spheroids from MCF‐7, SH‐SY5Y, and PC‐12 cell lines reveals the intensity profile of Pdots, confirming extensive penetration into the central regions of the models. Moreover, a comparison with mitochondria staining dye reveals an overlap between the regions stained by Pdots and the dye in all three tumor spheroid models. These results suggest that single‐chain D–A–D type Pdots, cationized via CTAB, exhibit long‐range mean free path of penetration (≈1 µm) in dense mediums and tumors. [ABSTRACT FROM AUTHOR]

A novel series of 2-cyano-3-(pyrazol-4-yl)-N-(thiazol-2-yl)acrylamide derivatives (3a–f) were synthesized using Knoevenagel condensation and characterized using various spectral tools. The weak nuclease activity of compounds (3a–f) against pBR322 plasmid DNA was greatly enhanced by irradiation at 365 nm. Compounds 3b and 3c, incorporating thienyl and pyridyl moieties, respectively, exhibited the utmost nuclease activity in degrading pBR322 plasmid DNA through singlet oxygen and superoxide free radicals' species. Furthermore, compounds 3b and 3c affinities towards calf thymus DNA (CT-DNA) and bovine serum albumin (BSA) were investigated using UV–Vis and fluorescence spectroscopic analysis. They revealed good binding characteristics towards CT-DNA with Kb values of 6.68 × 104 M−1 and 1.19 × 104 M−1 for 3b and 3c, respectively. In addition, compounds 3b and 3c ability to release free radicals on radiation were targeted to be used as cytotoxic compounds in vitro for colon (HCT116) and breast cancer (MDA-MB-231) cells. A significant reduction in the cell viability on illumination at 365 nm was observed, with IC50 values of 23 and 25 µM against HCT116 cells, and 30 and 9 µM against MDA-MB-231 cells for compounds 3b and 3c, respectively. In conclusion, compounds 3b and 3c exhibited remarkable DNA cleavage and cytotoxic activity on illumination at 365 nm which might be associated with free radicals' production in addition to having a good affinity for interacting with CT-DNA and BSA. [ABSTRACT FROM AUTHOR]

Manganese Mercury Thiocyanate Glycol MonoMethyl Ether (MMTCGMME) crystal is grown at room temperature by slow evaporation technique. The sample grown is confirmed by single crystal XRD and CHNSO analysis for elements. The single crystalline XRD of MMTCGMME crystal are 16.2052 Å, 7.2981 Å, and 13.5099 Å for a, b, c. The crystalline system is orthorhombic with space group as Pca21 which is the non-centrosymmetric type. The cut-off wavelength of MMTCGMME crystal is 206 nm is confirmed by absorbance spectrum. The bandgap value as 6 eV is confirmed by Tauc's plot for photonic use. The SEM morphological representation shows that there is no flaws and no defects in MMTCGMME. Phase matching provisioning of the MMTCGMME crystal material for particle size is observed that compared to KDP 1.845 times having higher second-order NLO coefficients than KDP. The MMTCGMME crystal has very low value of dielectric constant at higher frequencies and it is having higher dielectric constant value at lower frequency range is important for material and device fabrication The fluorescence analysis is reported with the emission at 489 nm for the excitation value of 250 nm of bluish green fluorescence emission. The piezoelectric coefficient is 5.2 pC/N for MMTCGMME. The red LED-based sensitivity is 8% at the room temperature of 28.9 °C. [ABSTRACT FROM AUTHOR]

The Li3LaMgTiO6 phosphor doped with Mn4+ was synthesized using the solid phase gradient temperature technique. The micro-structure and spectral properties were characterized through XRD and fluorescence spectrum analysis. The experimental results demonstrate that it exhibits a typical layered structure, and the gradient temperature technique can effectively modify and distort the crystal cell structure from tetrahedral to cubic system. This transformation alters the required octahedral structure for Mn4+, resulting in the splitting of 2A levels into 2Eg and 2T1, thereby enlarging the energy level spacing. Consequently, due to reduced non-radiative transition probability of 2T1 → 2Eg, a blue shift phenomenon will be formed in the fluorescence peak. By utilizing a 358 nm LED as a pump source, we observed this phenomenon in fluorescence peaks from 711 to 680 nm. Furthermore, by adjusting the gradient temperature zone, it is possible to obtain a full-width half-maximum (FWHM) rectangular fluorescence spectrum up to 100 nm with excellent homogeneity of light intensity, which holds great promise for applications in opto-electronics and crop fields. [ABSTRACT FROM AUTHOR]

Exploring the intrinsic mechanisms of rare-earth ions entering the crystal phase has great significance for finely tuning the luminescent properties of glass–ceramics. Using Er3+ ions as a probe, X-ray diffraction was employed to precisely measure the crystallinity of SiO2-PbF2-Er2O3 glass–ceramics synthesized under various heat treatment conditions, confirming the occurrence of a rapid crystallization process. Additionally, by combining Judd–Ofelt theory with comprehensive analyses of absorption and fluorescence spectra, we calculated the relative proportions of Er3+ ions present in the crystal phase. We found that the crystallization process in the glass–ceramics and the incorporation of Er3+ ions into the crystal phase did not occur synchronously. This discovery provides new theoretical foundations and practical guidance for understanding the mechanism of rare-earth ion incorporation into crystal phases, which is significant for the development of functional materials with specific luminescent properties. [ABSTRACT FROM AUTHOR]

The capability of amyloid‐like peptide fibers to emit intrinsic‐fluorescence enables the study of their formation, stability and hardening through time‐resolved fluorescence analysis, without the need for additional intercalating dyes. This approach allows the monitoring of amyloid‐like peptides aggregation kinetics using minimal sample volumes, and the simultaneous testing of numerous experimental conditions and analytes, offering rapid and reproducible results. The analytical procedure applied to the aromatic hexapeptide F6, alone or derivatized with PEG (polyethylene glycol) moiety of different lengths, suggests that aggregation into large anisotropic structures negatively correlates with initial monomer concentration and relies on the presence of charged N‐ and C‐termini. PEGylation reduces the extent of aggregates hardening, possibly by retaining water, and overall impacts the final structural properties of the aggregates. [ABSTRACT FROM AUTHOR]

Background: The axillary vein is preferred over the subclavian vein, and the cephalic vein for cardiac implantable electronic device (CIED) lead insertion. However, studies on ultrasound-guided axillary vein access (US-AVA) in Asia are scarce. This study aims to evaluate the feasibility of US-AVA for CIED lead implantation in Korean patients. Methods: From September 2021 to September 2023, we employed US-AVA for CIED lead implantation procedures. Patients' demographic and procedural data were collected and analyzed retrospectively. Results: US-AVA was successful in 301 patients (97.7%). There were no occurrences of pneumothorax or severe hematoma due to inadvertent arterial puncture, nor were there any other significant vascular access-related acute complications. During the median 1.7 years of follow-up, no CIED infection or lead-related problems have occurred. Compared to a historical cohort of patients who underwent fluoroscopy-guided axillary vein access (FL-AVA), US-AVA significantly reduced procedure and fluoroscopy time and showed a trend toward reduced radiation doses. Conclusion: US-AVA is a safe and effective technique for CIED lead implantation in Korean patients, with advantages over FL-AVA in terms of procedural efficiency and patient safety. [ABSTRACT FROM AUTHOR]

How G proteins inhibit N-type, voltage-gated, calcium-selective channels (CaV2.2) during presynaptic inhibition is a decades-old question. G proteins Gβγ bind to intracellular CaV2.2 regions, but the inhibition is voltage dependent. Using the hybrid electrophysiological and optical approach voltage-clamp fluorometry, we show that Gβγ acts by selectively inhibiting a subset of the four different CaV2.2 voltage-sensor domains (VSDs I to IV). During regular "willing" gating, VSD-I and -IV activations resemble pore opening, VSD III activation is hyperpolarized, and VSD II appears unresponsive to depolarization. In the presence of Gβγ, CaV2.2 gating is "reluctant": pore opening and VSD I activation are strongly and proportionally inhibited, VSD IV is modestly inhibited, while VSD III is not. We propose that Gβγ inhibition of VSDs I and IV underlies reluctant CaV2.2 gating and subsequent presynaptic inhibition. [ABSTRACT FROM AUTHOR]

Reasonable design and preparation of effective interface engineering to accelerate charge transfer is the key to achieve the improvement of heterojunction photocatalysts. In this study, a Ti 3 C 2 -MoS 2 -ZnIn 2 S 4 (TMZ) heterojunction was designed and successfully synthesized by sequentially growing MoS 2 and ZnIn 2 S 4 layered structures on highly conductive Ti 3 C 2 using a two-step hydrothermal method. This configuration effectively separated photogenerated carrier, thereby improving the efficiency of photocatalytic hydrogen production. The effects of the amount of Ti 3 C 2 -MoS 2 on the microstructure, morphology, optical properties and photocatalytic H 2 production of TMZ heterojunctions were investigated. Results demonstrated that Ti 3 C 2 , MoS 2 , and ZnIn 2 S 4 intricately interpenetrated to form a tightly bound TMZ heterojunction with a well-defined heterojunctions interface. This interface is beneficial for the separation of photogenerated carriers, thereby boosting the photocatalytic performance. The dynamic process of carrier separation was investigated in detail using photocurrent measurements, EIS Nyquist plots, photoluminescence, and fluorescence lifetime analysis. Additionally, compared to pristine ZnIn 2 S 4 , the absorption edge of TMZ sample exhibited a redshift, indicating an expanded absorption range in the visible spectrum. Finally, the mechanism by which TMZ enhances the efficiency of photocatalytic H 2 production is thoroughly analyzed. • Ti 3 C 2 -MoS 2 -ZnIn 2 S 4 consist of three-layered materials, effectively separating carriers. • Ti 3 C 2 -MoS 2 -ZnIn 2 S 4 enhances visible light absorption and augments active sites availability. • The optimized photocatalytic H 2 efficiency is enhanced to 4398 μmol g-1 h-1. [ABSTRACT FROM AUTHOR]