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In this work, the absorption spectra of metastable Dy2+, Nd2+, and Sm2+  are identified in SrAl2O4:Eu,Ln persistent phosphors after excitation with blue light, thereby confirming that the persistent luminescence is indeed due to a charge transfer between the two lanthanide dopants. In contrast to previous studies relying on X‐ray absorption spectroscopy to observe charge transfers between dopants, here low‐energy light is exclusively employed to probe for changes in the absorption spectrum of the phosphor, thereby only minimally affecting the state of the phosphor. Optical bleaching in combination with thermoluminescence measurements allowed to assign which optically active trapping centers contribute to the afterglow of the persistent phosphors. [ABSTRACT FROM AUTHOR]

In the present study, we focused on the development and characterization of formulations that function as biological inks. These inks were doped with coumarin derivatives to act as molecular luminescent sensors that allow the monitoring of the kinetics of in situ photopolymerization in 3D (DLP) printing and bioprinting using pneumatic extrusion techniques, making it possible to study the changes in the system in real time. The efficiency of the systems was tested on compositions containing monomers: poly(ethylene glycol) diacrylates and photoinitiators: 2,4,6-trimethylbenzoyldi-phenylphosphinate and lithium phenyl-2,4,6-trimethylbenzoylphosphinate. The selected formulations were spectroscopically characterized and examined for their photopolymerization kinetics and rheological properties. This is important because of the fact that spectroscopic characterization, examination of photopolymerization kinetics, and rheological properties provide valuable insights into the behaviour of photocurable resin dedicated for 3D printing processes. The next step involved printing tests on commercially available 3D printers. In turn, printing carried out as part of the work on commercially available 3D printers further verified the effectiveness of the formulations. Moreover the formulation components and the resulting 3D objects were tested for their antiproliferative effects on the selected Chinese hamster ovary cell line, CHO-K1. [Display omitted] • Bioinks doped with luminescent sensors for in situ photopolymerization monitoring. • Applications of bioinks at DLP and pneumatic extrusion 3D printing technique. • Cytotoxicity of the sensors in the tested range has not been indicated. • Intense Vis-LED radiation (405 nm) does not have a damaging effect on cells. [ABSTRACT FROM AUTHOR]

In contrast to lead-based materials, lead-free ceramics Ba 0.85 Ca 0.15 Zr 0.10 Ti 0.90 O 3 (BCZT) offer outstanding dielectric, ferroelectric, and piezoelectric properties. A novel sonochemical method is employed to synthesize BCZT at low temperatures. The impact of high-energy acoustic waves reduces the calcination temperature to 600 °C, which is 300–400 °C lower than the already reported values. The samples are further sintered at different temperatures. The BCZT shows good dielectric properties (ε r ∼3000 and tanδ ∼0.075 at 1 kHz) at room temperature. X-ray diffraction analysis shows the co-existence of tetragonal and orthorhombic phases. Further, the scaling behavior is studied for domain dynamics in the sample. A three-stage polarization reversal mechanism is observed in BCZT ceramics. From the systematic study of the domain reversal mechanism, BCZT appears to be a promising candidate for sensors and actuator applications. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusions The aim of this work was to investigate the solubility and co‐solubilization of fragrance raw materials (FRMs) in sodium dodecyl sulfate (SDS) and polysorbate 20 (P20) surfactant micellar systems, which can advance our knowledge of multi‐solute micellar solubilization and fragrance olfactory performance from product matrices containing the surfactants.The transfer of individual FRMs and binary FRM mixtures into micellar phases was quantified by UV–VIS differential spectroscopy and evaluated in terms of the standard Gibbs free energy change and micelle‐water partition coefficient. Co‐solubilization effects were further evaluated by the deviation ratio.Anionic SDS was found overall to be a more efficient solubilizer than nonionic P20. On an individual basis, micellar solubilization generally increased with solute lipophilicity but was additionally impacted by solute rigidity and steric effects. Micellar solubilization was favoured for more rigid structures and less favoured for FRMs that exhibited larger molecular rotation and steric hindrance. For multi‐solute systems, three co‐solubilization effects were observed: (i) inhibitive effect in which micellar partitioning of both solutes decreased, (ii) an inverse effect where partitioning of one solute increased while the other decreased and (iii) synergistic effect in which partitioning of both solutes increased. During co‐solubilization in P20 micelles, many FRMs competed for solubilization between the polyoxyethylene chains in the outer layer of the micelle, thereby resulting in an inhibitory effect for both solutes. Co‐solubilization of FRM binary mixtures in SDS micelles often resulted in a synergistic increase in micellar solubility, possibly due to micellar swelling, thereby facilitating partitioning of additional solutes into the micelle. An inverse effect in which the micellar solubility of one solute increased, while the other decreased was observed in both surfactant systems with varying degrees of partitioning depending on the composition of the FRM mixture.The results of this study provide valuable insights into the impact of FRM composition on multi‐solute partitioning behaviour and the impact of surfactant type on co‐solubilization in micellar solutions. [ABSTRACT FROM AUTHOR]

ZrO is a well-studied metal monoxide because of its astrophysical importance in characterizing S stars. The bands of the d 3Φ–a3Δ system (γ system) with v ′ ≤ 4 and v ″ ≤ 5 are rotationally analyzed using the PGOPHER program to provide spectroscopic constants. The high-resolution ZrO emission spectrum was recorded with a Fourier transform spectrometer using a high-temperature carbon furnace source. New ab initio calculations of the transition dipole moment were carried out in order to determine the vibronic band strengths. The spectroscopic constants, along with the band strengths, are used to calculate a line list for the γ system. This line list can be used to determine Zr abundances in S stars. We also correct the line strengths for the B 1Π– A 1Δ transition calculated in our previous work. [ABSTRACT FROM AUTHOR]

By means of vibrational spectroscopy, the study examines the structure of matrix materials synthesized through the quenching of sodium-rubidium aluminoborosilicate melts with the addition of zirconium. Zirconium was found to have a significant effect on the ratio of the main structural units and the distribution of modifier cations among them in the glass structure. The obtained results were used to explain changes in the glass-melt transition temperature and synthesized material density; they can be useful in adjusting the composition and synthesis parameters of matrix materials for the immobilization of high-level radioactive waste containing significant amounts of zirconium. [ABSTRACT FROM AUTHOR]

Phthalides represent a notable category of secondary metabolites that are prevalent in various plant species, certain fungi, and liverworts. The significant pharmacological properties of these compounds have led to the synthesis of a novel phthalide derivative. The current study focuses on investigating the binding interactions of a newly synthesized 3-substituted phthalide derivative, specifically 3-((4-chloro-6-methyl pyrimidine-2-yl)amino) isobenzofuran-1(3H)-one (Z11), with double-stranded deoxyribonucleic acid (dsDNA). Research in the pharmaceutical and biological fields aimed at developing more potent DNA-binding agents must take into account the mechanisms by which these newly synthesized compounds interact with DNA. This investigation seeks to explore the binding dynamics between dsDNA and our compound through a variety of analytical techniques, such as electrochemistry, UV spectroscopy, fluorescence spectroscopy, and thermal denaturation. The binding constant (Kb) of Z11 with DNA was determined using both spectroscopic and voltammetric approaches. The research revealed that Z11 employs a groove binding mechanism to associate with dsDNA. To further explore the interactions between Z11 and dsDNA, the study utilized density functional theory (DFT) calculations, molecular docking, and molecular dynamics simulations. These analyses aimed to ascertain the potential for a stable complex formation between Z11 and dsDNA. The results indicate that Z11 is situated within the minor groove of the dsDNA, demonstrating the ability to establish a stable complex. Furthermore, the findings imply that both π-alkyl interactions and hydrogen bonding play significant roles in the stabilization of this complex. [ABSTRACT FROM AUTHOR]

Functional near‐infrared spectroscopy (fNIRS) stands poised to revolutionize our understanding of auditory detection, speech perception, and language development in infants. In this study, we conducted a meticulous integrative review across Medline, Scopus, and LILACS databases, targeting investigations utilizing fNIRS to explore language‐related features and cortical activation during auditory stimuli in typical infants. We included studies that used the NIRS technique to study language and cortical activation in response to auditory stimuli in typical infants between 0 and 3 years old. We used the ROBINS‐I tool to assess the quality and the risk of bias in the studies. Our analysis, encompassing 66 manuscripts, is presented in standardized tables for streamlined data extraction. We meticulously correlated findings with children's developmental stages, delineating crucial insights into brain development and its intricate interplay with language outcomes. Although most studies have a high risk for overall bias, especially due to the high loss of data in NIRS studies, the low risk in the other domains is predominant and homogeneous among the studies. Highlighted are the unique advantages of fNIRS for pediatric studies, underscored by its innate suitability for use in children. This review accentuates fNIRS' capacity to elucidate the neural correlates of language processing and the sequential steps of language acquisition. From birth, infants exhibit abilities that lay the foundation for language development. The progression from diffuse to specific neural activation patterns is extremely influenced by exposure to languages, social interaction, and prosodic features and, reflects the maturation of brain networks involved in language processing. In conclusion, fNIRS emerges as an indispensable functional imaging modality, providing insights into the temporal dynamics of language acquisition and associated developmental milestones. This synthesis presents the pivotal role of fNIRS in advancing our comprehension of early language development and paves the way for future research endeavors in this domain. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to identify the neural pattern activation during mirror therapy (MT) and explore any cortical reorganization and reducing asymmetry of hemispheric activity for upper limb rehabilitation in post-stroke patients. Methods: A box containing a mirror was placed between the arms of the patients to create the illusion of normal motion in the affected limb by reflecting the image of the unaffected limb in motion. We measured the cerebral hemodynamic response using near-infrared spectroscopy (NIRS). We enrolled ten right-handed stroke patients. They observed healthy hand movements in the mirror (MT condition) while performing various tasks (MT condition), and then repeated the same tasks with the mirror covered (N-MT condition). Results: Significant activation of some brain areas was observed in the right and left hemiparesis groups for the MT condition, while lower levels of activation were observed for the N-MT condition. The results showed significant differences in hemodynamic response based on oxygenated (HbO) concentrations between MT and N-MT conditions across all tasks in sensorimotor areas. These neural circuits were activated despite the motor areas being affected by the brain injury, indicating that the reflection of movement in the mirror helped to activate them. Conclusions: These results suggest that MT promotes cortical activations of sensory motor areas in affected and non-affected brain sides in subacute post-stroke patients, and it encourages the use of these tools in clinical practice. [ABSTRACT FROM AUTHOR]

Broadband spectral measurements of the ballistic transmission of scattering samples are challenging. The presented work shows an approach that includes a broadband system and an automated adjustment unit for compensation of angular distortions caused by non-plane-parallel samples. The limits of the system in terms of optimal transmission and detected forward scattering influenced by the scattering phase function are investigated. We built and validated a setup that measures the collimated transmission signal in a spectral range from 300 nm to 2150 nm. The system was validated using polystyrene spheres and Mie calculations. The limits of the system in terms of optimal transmission and detected forward scattering were researched. The optimal working parameters of the system, analyzed by simulations using the Monte Carlo method, show that the transmission should be larger than 10% and less than 90% to allow for a reliable measurement with acceptable errors caused by noise and systematic errors of the system. The optimal transmission range is between 25% and 50%. We show that the phase function is important when considering the accuracy of the measurement. For strongly forward-scattering samples, errors of up to 80% can be observed, even for a very small numerical aperture of 6.6 · 10 − 4 , as used in our experimental system. We also show that errors increase with optical thickness as the ballistic transmission decreases and the multiscattered fraction increases. In addition, errors caused by multiple reflections in the sample layer were analyzed and also classified as relevant for classical absorption spectroscopy. [ABSTRACT FROM AUTHOR]

Background: Patients with circulatory failure have high mortality rates and require prompt assessment of microcirculation. Despite the improvement in hemodynamic parameters, microcirculatory dysfunction persists. We measured subcutaneous regional tissue oxygen saturation (rSO2) with near-infrared spectroscopy (NIRS), which can assess microcirculation in patients with circulatory failure. Methods: A finger-worn oximeter with NIRS measured rSO2 in the forehead, thenar eminence, thumb, and knees. First, the rSO2 was measured in healthy adult volunteers (n = 10). Circulatory failure was defined as a systolic blood pressure ≤ 90 mmHg and lactate ≥ 2 mmol/L. The study included 35 patients without circulatory failure and SOFA score of 0 at ICU admission and 38 patients with circulatory failure at ICU admission. Both groups included a single-center prospective study of patients who were transported to the ICU of the Nihon University Hospital. The rSO2 was measured only on ICU admission in the non-circulatory failure group and later in the circulatory failure group. Results: In the volunteer group, rSO2 at each site was approximately 58%. The rSO2 was significantly lower in the circulatory failure group than in the non-circulatory failure group (knee, p < 0.01). In the circulatory failure group, knee rSO2 showed a significant negative correlation with SOFA score (Day 0, ρ = −0.37, p = 0.02; Day 1, ρ = −0.53, p < 0.01; Day 2, ρ = −0.60, p < 0.01). Conclusions: Subcutaneous knee rSO2 was associated with SOFA score and was considered an indicator of microcirculatory dysfunction and organ damage. [ABSTRACT FROM AUTHOR]

Introduction The U.S. Military members experiencing combat-related injuries have a higher chance of developing infections by multidrug-resistant (MDR) bacteria at admission to military hospitals. MDR wound infections result in higher amputation rates and greater risks for subsequent or chronic infections that require readmission or extended stay in the hospital. Currently, there is no FDA-clear, deployable early diagnostic system for suitable field use. We are reporting our efforts to improve a previously developed Rapid Label-free Pathogen Identification (RAPID) system to detect viable MDR bacteria in wound infections and perform antibiotic susceptibility testing (AST). Specifically, we added multiplex and automation capability and significantly simplified the sample preparation process. A functional prototype of the improved system was built, and its performance was validated using a variety of lab-prepared spiked samples and real-world samples. Materials and Methods To access the baseline performance of the improved RAPID system in detecting bacteria presence, we selected 17 isolates, most of them from blood or wound infections, and prepared mono-strain spiked samples at 104 to 106 cfu/mL concentration. These samples were processed and analyzed by the RAPID system. To demonstrate the AST capability of the system, we selected 6 strains against 6 different antibiotics and compared the results from the system with the ones from the gold standard method. To validate the system's performance with real-world samples, we first investigated its performance on 3 swab samples from epicutaneous methicillin-resistant Staphylococcus aureus –exposed mouse model. The AST results from our system were compared with the ones from the gold standard method. All animal experiments were approved by the Johns Hopkins University Animal Care and Use Committee (Protocol No. MO21M378). Then, we obtained swab samples from 7 atopic dermatitis (AD) patients and compared our AST results with the ones from the gold standard method. The human subject protocol was approved by the Johns Hopkins Medicines Institutional Review Boards (Study No. CR00043438/IRB00307926) and by USAMRDC (Proposal Log Number/Study Number 20000251). Results High-quality data were obtained from the spiked samples of all 17 strains. A quantitative analysis model built using these data achieved 94% accuracy in predicting the species ID in 8 unknown samples. The AST results on the spiked samples had shown 100% matching with the gold standard method. Our system successfully detects the presence/absence of viable bacteria in all 3 mouse and 7 AD patient swab samples. Our system shows 100% and 85.7% (6 out of 7) accuracy when compared to the oxacillin susceptibility testing results for the mouse and the AD patient swabs, respectively. Conclusions Our system has achieved excellent performance in detecting viable bacteria presence and in performing AST in a multiplex, automated, and easy-to-operate manner, on both lab-prepared and real samples. Our results have shown a path forward to a rapid (sample-to-answer time ≤3 hours), accurate, sensitive, species-specific, and portable system to detect the presence of MDR combat-related wound infections in the field environment. Our future efforts involve ruggedizing the RAPID system and evaluating performance under relevant environmental conditions. [ABSTRACT FROM AUTHOR]

This paper explores the microfabrication process of plasma reactors, from the production of micro-reactors to the addition of through silicon vias (TSV) using proprietary etching techniques and on site cleanroom facilities. The investigation focuses on both newly fabricated closed and open-cavity micro-hollow cathode discharge (MHCD) reactors, with particular emphasis on electrical and optical diagnostics to characterize their plasma properties. All experiments, including those on closed-cavity reactors, were specifically conducted for this study under identical conditions to ensure a rigorous comparison between reactor types. When electrical diagnostics were carried out in helium at various pressures, interesting phenomena such as the evolution of voltage breakdown were observed. These diagnostics also provided new insights into the impact of surface electrode and overall geometry properties and pressure on reactor performance. Additional investigation into instability mechanisms revealed self-pulsing oscillations, with different reactor types having different oscillation amplitudes for similar operating conditions. Optical emission spectroscopy (OES) emerged as a strong tool for spatial plasma analysis, revealing consistent gas temperature distributions across reactor diameters. The Inglis-Teller series provided an estimate of the upper limit of electron density, while the Stark broadening analysis of H α offered valuable insights into electron density variations, particularly in the self-pulsing regime. [ABSTRACT FROM AUTHOR]

Accurate classification of transients obtained from spectroscopic data are important to understand their nature and discover new classes of astronomical objects. For supernovae (SNe), SNID, NGSF (a Python version of SUPERFIT), and DASH are widely used in the community. Each tool provides its own metric to help determine classification, such as rlap of SNID, chi2/dof of NGSF, and Probability of DASH. However, we do not know how accurate these tools are, and they have not been tested with a large homogeneous data set. Thus, in this work, we study the accuracy of these spectral classification tools using 4646 SEDMachine spectra, which have accurate classifications obtained from the Zwicky Transient Facility Bright Transient Survey (BTS). Comparing our classifications with those from BTS, we have tested the classification accuracy in various ways. We find that NGSF has the best performance (overall Accuracy 87.6% when samples are split into SNe Ia and Non-Ia types), while SNID and DASH have similar performance with overall Accuracy of 79.3% and 76.2%, respectively. Specifically for SNe Ia, SNID can accurately classify them when rlap > 15 without contamination from other types, such as Ibc, II, SLSN, and other objects that are not SNe (Purity > 98%). For other types, determining their classification is often uncertain. We conclude that it is difficult to obtain an accurate classification from these tools alone. This results in additional human visual inspection effort being required in order to confirm the classification. To reduce this human visual inspection and to support the classification process for future large-scale surveys, this work provides supporting information, such as the accuracy of each tool as a function of its metric. [ABSTRACT FROM AUTHOR]

The formation of bacterial biofilms in the human body and on medical devices is a serious human health concern. Infections related to bacterial biofilms are often chronic and difficult to treat. Detailed information on biofilm formation and composition over time is essential for a fundamental understanding of the underlying mechanisms of biofilm formation and its response to anti-biofilm therapy. However, information on the chemical composition, structural components of biofilms, and molecular interactions regarding metabolism- and communication pathways within the biofilm, such as uptake of administered drugs or inter-bacteria communication, remains elusive. Imaging these molecules and their distribution in the biofilm increases insight into biofilm development, growth, and response to environmental factors or drugs. This systematic review provides an overview of molecular imaging techniques used for bacterial biofilm imaging. The techniques included mass spectrometry-based techniques, fluorescence-labelling techniques, spectroscopic techniques, nuclear magnetic resonance spectroscopy (NMR), micro-computed tomography (µCT), and several multimodal approaches. Many molecules were imaged, such as proteins, lipids, metabolites, and quorum-sensing (QS) molecules, which are crucial in intercellular communication pathways. Advantages and disadvantages of each technique, including multimodal approaches, to study molecular processes in bacterial biofilms are discussed, and recommendations on which technique best suits specific research aims are provided. [ABSTRACT FROM AUTHOR]

Four isomeric nitrosyl ruthenium complexes [RuCl(2mqn)(Val)(NO)] (1 – 4) were prepared (2mqn, 2-methyl-8-hydroxyquinoline; Val, l -valine) and characterized by 1H NMR, 13C NMR, absorption spectrum, electrospray ionization mass spectrometry, and X-ray crystal diffraction. Time-resolved FT-IR and fluorescence spectroscopy were used to monitor photo-induced NO release in solution, while NO released in living cells was imaged using a selective fluorescent probe. The isomeric complexes showed different levels of cytotoxicity against HeLa cells, and slightly photo-enhanced anti-proliferative activity was observed. The isomeric complexes 1 – 4 inhibited the growth of HeLa cells by inducing apoptosis and promoted cell cycle arrest in the S phase. Furthermore, they showed relatively lower cytotoxicity against the human liver cell line HL-7702. The different spatial configurations of the complexes is close related with the selective binding of the isomeric complexes with serum albumin, which provide insight into the potential applications of the nitrosyl ruthenium complexes. [Display omitted] • Nitrosyl ruthenium isomeric complexes were synthesized. • Photo-induced NO release was observed. • The cytotoxicity of the isomeric complexes was evaluated. • The interaction model with human serum albumin was determined. [ABSTRACT FROM AUTHOR]

Summary: This study aimed to get mechanistic insights on the evolution of major quality attributes of meat‐analogue (MA) based batter‐coated fried products. Wheat and rice flour‐based batter systems were used to coat a MA. The products were deep‐fried at 180°C for 4 min in canola oil and their post‐fry quality changes at room environment (RE, 25°C) and under IR‐heating (65 °C) were investigated. Results showed that in addition to moisture‐fat profile, batter coating substantially (P < 0.05) influenced the development of thermal, textural, colour and microstructural traits of MA. Post‐fry colour changes (ΔE value: 3.1 to 10.4) in MA‐based coated product continued under IR‐heating (65 °C). Evolution of the thermal, textural and colour attributes of MA‐based coated products were significantly (P < 0.05) influenced by the formulation of outer batter coatings. Moisture migration occurred from high moisture (ranged from 1.07 to 1.25 g g−1 dry matter) containing core to dry (moisture ranged from 0.15 to 0.59 g g−1 dry matter) crust region of MA‐based coated fried product, where the moisture migration was interlaced with batter formulations. Holding environment and duration substantially (P < 0.05) impacted the textural properties (hardness, brittleness and crispiness) of MA‐based coated fried product. Glass transition temperature (Tg) of coated fried products were ranged between −20.4 to −23.0 °C, that explains quality changes at RE and under IR‐heating. Scanning electron microscopic image analysis (surface openings: 5.7 to 27.31%; fractal dimension: 2.555 to 2.702) revealed the impact of surface microstructure and mass‐transfer modulated textural development in MA‐based coated products. FTIR spectroscopy revealed surface chemical profile in relation to colour evolution of MA‐based fried products. Principal component analysis outcome (PC1: 52.9.% and PC2: 25.8%) revealed varying extent of correlation between studied thermomechanical and physicochemical attributes. [ABSTRACT FROM AUTHOR]

This study aims to address critical challenges such as global warming and energy sustainability by targeting the reduction of high NOx emissions in diesel engines. The effects of acetone (AC) and magnesium oxide (MgO) nanoparticles (NPs) as additives in improving the physicochemical properties of biodiesel derived from renewable, nonedible Pistacia terebinthus oil, which is abundant in Turkey and has a high free fatty acid (FFA) content of 5.8%, were investigated. Due to the high FFA content, a two‐step (esterification followed by transesterification [TR]) method was used for biodiesel production. Additionally, a quantitative analysis of biodiesel obtained by both single (TR) and two‐step methods was performed to address a gap in the literature. The addition of AC and MgO NPs to B20 (80% diesel fuel and 20% biodiesel) fuel resulted in reductions in the rate of pressure rise, instantaneous energy release, cylinder pressure, mean gas temperature, and cumulative heat release rate. However, brake‐specific fuel consumption increased, and brake thermal efficiency decreased. Emissions analyses showed a reduction in CO emissions by 6.65% with AC and 2.10% with AC + MgO, and a reduction in NOx emissions by 41.64% with AC and 46.03% with AC + MgO. However, hydrocarbon emissions increased by 26.48%. The study highlights the synergistic benefits of AC and MgO additives in biodiesel, presenting a viable strategy for improving the environmental and performance metrics of biodiesel blends. It provides new insights into alternative fuel formulations. [ABSTRACT FROM AUTHOR]

In this study, terahertz time‐domain spectroscopy (THz‐TDS) is employed for the first time to explore the characteristics of mono‐, bi‐, and tri‐layer graphene coated on guided‐mode resonance filters (GMRFs). Owing to high quality‐factor (Q‐factor) resonances of GMRF, the proposed method significantly enhances the resonance depth variation by up to 9.3, 5.1, and 4.2 times at 0.58 THz in TE mode for mono‐, bi‐, and tri‐layer graphene, respectively, in contrast to conventional THz‐TDS methods relying on amplitude variation at 0.50 THz in TE mode. Excellent agreement is observed between experimental results and theoretical simulations using the Kubo formula and Drude model, even accounting for variations in sidelobes at an incident angle of 0.6 degrees. Through meticulous fitting process between measurements and simulations for the resonances formed by the GMRF and graphene, the study accurately determines the electrical and optical properties of mono‐, bi‐, and tri‐layer graphene, including frequency‐dependent sheet conductivity (σs(ω)), mobility (μ), carrier density (N), and Fermi velocity (vF). Furthermore, in the THz high‐frequency region, the observation reveals that as the number of graphene layers increases, the decrease in σs(ω) occurs more rapidly than in single‐layer graphene, attributed to the screening effect arising from electronic interactions between each graphene layer. [ABSTRACT FROM AUTHOR]

Background Purpose Methods Results Conclusion In 4D dynamic contrast‐enhanced dedicated breast computed tomography (4D DCE‐bCT), the functional properties of the breast will be characterized by monitoring the uptake and washout of iodine‐based contrast agents over time. This information could be valuable in breast cancer treatment. However, prior to clinical implementation, it is crucial to validate the quantitative estimates of iodine concentrations at each time point during acquisition.To develop an in‐line spectroscopy system capable of measuring iodine concentrations in a dynamic x‐ray breast phantom in real‐time.Potassium iodide served as the contrast agent. The system was set‐up at both the entrance and exit of the phantom. It comprises a fiber‐coupled green LED and collimator, which together ensure that a parallel beam passes through the sample holder. Transmitted light is captured by a collimator on the opposite side and directed through a fiber optic cable to a photodetector for intensity measurement. The relationship between 13 iodine concentrations (0–6 mg I/mL) and light transmission was tested, and the system's repeatability and accuracy were determined.The system exhibited a strong correlation between iodine concentration and transmission values, achieving a root‐mean‐square error of 0.007. The repeated measurements had relative standard deviations of 0.04% and 0.1% for repeated water measurements at the phantom's entrance and exit, respectively. Furthermore, the accuracy measurements gave a mean error of fitting of 0.008 (± 0.07) mg I/mL.The in‐line spectroscopy system can effectively monitor iodine concentrations in a dynamic breast phantom, providing a reliable method for quantitative validation of 4D DCE‐bCT. [ABSTRACT FROM AUTHOR]

In recent years, nitrogen‐based ruthenium complexes have become an important material for dye‐sensitized solar cells and photo‐catalytic H2O and CO2 reduction research and applications, thanks to their charge transfer feature from the metal to the ligand. The electronic and spectral properties of such materials can be easily modified by changing the substituents and ligands. In this study, a new ruthenium (II) complex with N‐functionalized pyrrole derivative ([Ru(bpy)2(bpyCONHArPy)]+2 complex) was successfully synthesized and characterized. Its optical and electrochemical properties were studied by means of fluorescence, UV‐vis spectrometry, FTIR spectroscopy and cyclic voltammetry. These results were compared with that of its components (4‐(1H‐pyrrol‐1‐yl) aniline, N4,N4′‐bis(4‐(1H‐pyrrol‐1‐yl)phenyl)‐[2,2′‐bipyridine]‐4,4′‐dicarboxamide and ligand [Ru(bpy)3]+2). Related theoretical studies were also studied to find energy levels of complex. The present work is carried out to understand what chemical changes bring when combination of all the pieces of the puzzle into a chemical structure step by step. [ABSTRACT FROM AUTHOR]

The ultrafast dynamics of photoexcited charge carriers are studied in micron‐scale crystals composed of the inorganic perovskite CsPbBr3 with time‐resolved terahertz spectroscopy. Exciting with photon energy close to the band edge, it is found that a fast (<10 ps) decay emerges in the terahertz photoconductivity with increasing pump fluence and decreasing temperature, dominating the dynamics at 4 K. The fluence‐dependent dynamics can be globally fit by a nonlinear recombination model, which reveals that the influence of different nonlinear recombination mechanisms in the studied pump fluence range depends on temperature. Whereas the Auger scattering rate decreases with decreasing temperature from 77 to 4 K, the radiative recombination rate increases by three orders of magnitude. Spectroscopically, the terahertz photoconductivity resembles a Drude response at all delays, yet an additional Lorentz component due to an above‐bandwidth resonance is needed to fully reproduce the data. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have emerged as a versatile class of materials. Understanding the structural and chemical properties of MOFs is essential for tailoring their performance to suit specific applications. In recent years, Raman spectroscopy, a non‐destructive vibrational spectroscopic technique, has evolved into a powerful tool for characterizing MOFs. Beyond spontaneous Raman scattering, numerous advanced Raman techniques have been developed to amplify the inherently weak Raman signal. These innovations have significantly enhanced the spatial resolution, frame rate, and sensitivity of Raman imaging, thereby opening up new possibilities for applications, such as label‐free sensing. This tutorial work is designed to demystify the fundamental theory and instrumentation of Raman spectroscopy, elucidating the differences between commonly used Raman techniques. Particular emphasis is placed on their advantages and limitations when applied to MOF materials. Furthermore, this work showcases how Raman techniques are employed in studying MOF systems to address societal needs and explore future directions. Ultimately, this review emphasizes the crucial role of Raman spectroscopy and the development of novel Raman‐based in situ techniques to conquer the field of MOFs. [ABSTRACT FROM AUTHOR]

In this semi‐quantitative study, laser crystal microparticles which are potentially capable of generating mid‐infrared (MIR) light are incorporated into MIR transmitting optical fibers using a volumetric interface doping technique that combines interface doping with volumetric doping. Using confocal microscopy with a refractive index matching fluid, the Er:YAP microcrystals (MCs) inside the tellurite glass fiber are observed based on the detection of the green upconversion fluorescence emission of Er3+ ions, produced under excitation at 976 nm and localized at the central region within the fiber. The key outcome from this proof‐of‐concept study is that MC particles that are fused with the glass during the fiber drawing process survived heat treatment because the MC particles are exposed for a short time to a glass fluid with high viscosity of ≈105 Pa.s, which prevented the glass from exerting a dissolution effect. The survival of the MCs demonstrated the viability of the doping technique for fabricating fibers with exotic crystal‐glass combinations for applications including good refractive index matching across the pump and lasing bands of rare earth ions. This latter parameter provides significant particle size flexibility whilst minimizing additional loss from scattering especially at MIR wavelengths where the MC diameter‐to‐wavelength ratio becomes smaller. [ABSTRACT FROM AUTHOR]

We explore the influence of radio-mode feedback on the properties of the cool circumgalactic medium (CGM). To this end, we assemble a statistical sample of approximately 30,000 radio galaxies with background quasars by combining optical spectroscopic measurements of luminous red galaxies and quasars from the year 1 data set of the Dark Energy Spectroscopic Instrument and radio sources from the LOw-Frequency ARray Two-metre Sky Survey (LoTSS) DR2 catalog and the Very Large Array Sky Survey (VLASS) quick-look catalog. Galaxies with similar optical properties but with no radio counterparts in LoTSS and VLASS are selected as the control group. We measure the cool CGM properties of radio galaxies and their control samples traced by Mg ii absorption lines, including covering fraction, rest equivalent width, and gas kinematics. Our results show no significant difference in the properties of gas around radio galaxies and their control sample, indicating that the operating radio-mode feedback of massive galaxies does not produce detectable effects on the properties of the cool CGM. Finally, we show that the CGM of radio galaxies contains a nonnegligible amount of cool gas with approximately 1010 M ⊙. This abundance can place a stringent constraint on the radio-mode feedback models. [ABSTRACT FROM AUTHOR]

We have performed wide-field, ultra-low-surface-brightness H α emission-line mapping around NGC 1068 with the newly commissioned Circumgalactic H α Spectrograph. NGC 1068 is notable for its active galactic nucleus, which globally ionizes gas in the disk and halo. Line-emitting diffuse ionized gas is distributed throughout the galactic disk and large-scale ionized filaments are found well beyond the disk, aligned with the cone angle of the central jet. We report the discovery of a new ribbon of ionized gas around NGC 1068 beyond even the known outer filamentary structure, located 20 kpc from the galaxy. The H α surface brightness of this ribbon is on the order of the bright telluric lines, ranging from 4 to 16 R, with fainter regions on the order of the sky background continuum. Unlike previous extended emission, the ribbon is not as well aligned with the current axis of the central jet. It is not associated with any galactic structure or known tidal features in the halo of NGC 1068, though it may originate from a larger distribution of unmapped neutral atomic or molecular gas in the halo. The morphology of the ribbon emission in H α is correlated with extended UV emission around NGC 1068. H α -to-UV flux ratios in the ribbon are comparable to extended emission-line ratios in the halos of NGC 5128, NGC 253, and M82. The H α excess in the ribbon gas suggests ionization by slow shocks or a mixture of in situ star formation and photoionization and collisional ionization processes. [ABSTRACT FROM AUTHOR]

Understanding the molecular mechanisms of differentiation is important for regenerative medicine and developmental biology. This study aims to characterise the role of the glycolysis/oxidative phosphorylation balance as a driver of mesenchymal stem cell (MSC) differentiation. Cells were maintained in normal conditions or stimulated towards the MSC trilineage cell types over 21 days. Multispectral imaging of cell autofluorescence was applied as a non-invasive methodology to continuously image cultures in situ. Spectral signals for collagen, NAD(P)H, and flavins were unmixed. MSCs cultured under chondrogenic conditions exhibited increased collagen levels relative to controls. Following osteogenic induction, MSCs showed increased collagen levels relative to controls during the earlier stages of culture; however, control cells increased their collagen levels as they became confluent. MSCs cultured under adipogenic conditions exhibited lower levels of collagen than controls. The redox ratio (RR; NAD(P)H/flavins) immediately decreased during chondrogenesis, with this early effect persisting throughout the culture compared to control cells, which appeared to increase their RR, similar to osteogenesis. Adipogenesis resulted in a small increase in RR on day 2 relative to control cells, followed by a persistent decrease. Chondrogenic and adipogenic differentiation favoured oxidative phosphorylation, whereas osteogenesis and MSC overgrowth resulted in a glycolytic metabolism. Following consideration of these findings, as well as the diverse reports in the literature, it is concluded that neither enhanced oxidative phosphorylation nor glycolysis are fundamental to the canonical modes of differentiation, and researchers should avoid interpreting shifts as indicating differentiation. [ABSTRACT FROM AUTHOR]

Background: This study highlighted the differences between the biochemical compositions of urinary stones from patients with type 1 diabetes versus those with type 2 diabetes. Materials and Methods: This study included patients diagnosed with kidney stones and diabetes who were referred to the Urological Clinic of the Dr. C. I. Parhon Hospital in Iasi from April 2017 to April 2024. We analyzed the spectroscopic stone composition from 128 lithiasis patients treated in our Clinic. In the current study, the distribution of the biochemical composition of stones varied significantly between diabetic patients with type 2 diabetes, who formed primarily mixed uric acid stones, and diabetic patients with type 1 diabetes, who mainly developed pure uric acid stones (p < 0.001). Patients with uric acid stones had significantly higher mean creatinine values than the other stone types (p < 0.001). Urinary pH levels were abnormal for all biochemical subtypes of stones, indicating acidic urine. However, patients with uric acid stones had lower pH values than the group average. From the Kaplan–Mayer analysis, patients with pure uric acid stones had a shorter time to stone recurrence compared to patients with other biochemical types identified. Conclusions: These findings, which highlight the prevalence of pure uric acid stones in patients with type 1 diabetes and the impact of this on the strategy for dissolving pure stones, represent a significant advancement in understanding urinary lithiasis in diabetic patients. [ABSTRACT FROM AUTHOR]

Vertical stratification in marine sediment profiles indicates physical and chemical sedimentary processes and, thus, is the first step in sedimentary research and in studying their relationship with global climate change. Traditional technologies for studying vertical stratification have low efficiency; thus, new technologies are highly needed. Recently, visible and near-infrared spectroscopy (VNIR) has been explored to rapidly determine sediment parameters, such as clay content, particle size, total carbon (TC), total nitrogen (TN), and so on. Here, we explored vertical stratification in a sediment column in the South China Sea using VNIR. The sediment column was 160 cm and divided into 160 samples by 1 cm intervals. All samples were classified into three layers by depth, that is, 0–50 cm (the upper layer), 50–100 cm (the middle layer), and 100–160 cm (the bottom layer). Concentrations of TC and TN in each sample were measured by Elementa Vario EL III. Visible and near-infrared reflectance spectra of each sample were collected by Agilent Cary 5000. A global model and several classification models for vertical stratification in sediments were established by a Support Vector Machine (SVM) after the characteristic spectra were identified using Competitive Adaptive Reweighted Sampling. In the classification models, K-means clustering and Density Peak Clustering (DPC) were employed as the unsupervised clustering algorithms. The results showed that the stratification was successful by VNIR, especially when using the combination of unsupervised clustering and machine learning algorithms. The correct classification rate (CCR) was much higher in the classification models than in the global model. And the classification models had a higher CCR using K-means combined with SVM (94.8%) and using DPC combined with SVM (96.0%). The higher CCR might be derived from the chemical classification. Indeed, similar results were also found in the chemical stratification. This study provided a theoretical basis for the rapid and synchronous measurement of chemical and physical parameters in sediment profiles by VNIR. [ABSTRACT FROM AUTHOR]

Butterfly wing scales feature complex nanostructures that influence wing coloration and various mechanical and optical properties. This configuration plays a key role in ecological interactions, flight conditions, and thermoregulation, facilitated by interactions with environmental electromagnetic energy. In tropical forests, butterflies occupy distinct vertical habitats, experiencing significant light and temperature variations. While wing nanostructures have been widely studied, their variation across different vertical flight preferences remains underexplored. This study investigates the wing nanostructures of 12 tropical butterfly species from the Nymphalidae family, focusing on their optical, morphological, and thermal properties across different forest strata. We analyzed the optical response through diffuse reflectance in the UV, Vis, and NIR ranges, correlating these findings with nanostructural configuration and thermal stability using thermogravimetric analysis (TGA). Our results reveal a significant correlation between flight stratification and wing optical responses, alongside distinct nanostructural features within each stratum. This study demonstrates the variability in butterfly wing nanostructures along the vertical stratification of the forest to cope with environmental conditions, raising new questions for future research on eco-evolutionary flight and thermal adaptations. Additionally, this underscores the importance of understanding how these structural adaptations influence butterfly interactions with their environment and their evolutionary success across different forest strata. [ABSTRACT FROM AUTHOR]

AbstractA critical limitation in developing portable Fourier transform-infrared (FTIR) stand-off chemical detectors is the library optimization which reduces the number of false alarms and maintains the performance. Ideally, a library should be established through high-resolution (0.5 cm−1) FTIR spectroscopy in the laboratory. However, due to the weight requirements of a portable FTIR stand-off detector, its optical system and mirror-moving range have limitations. Consequently, most portable FTIR stand-off detectors have been developed with a low resolution of approximately 4 to 16 cm−1. In this study, we developed a portable FTIR stand-off detector with a dual library of SF6. Moreover, we investigated its detection efficiency depending on the single library condition through realistic long-range (3 km) SF6 spectra in a field test. [ABSTRACT FROM AUTHOR]

ABSTRACT Lavender, widely cultivated in the Mediterranean region, produces essential oil known for its significant biological activities and is a key component of the perfume industry due to its high levels of Linalool and Linalyl acetate, along with low Camphor content, which contributes to its high cost. However, the market is plagued by adulterated lavender oil, often mixed with cheaper alternatives such as eucalyptus and rosemary. Current detection methods, primarily gas chromatography, are expensive, time‐consuming and often fail to detect low levels of adulteration. To address these limitations, this study examines the use of mid‐infrared spectroscopy for the detection and prediction of adulteration levels. A set of 105 samples, comprising pure lavender oil and adulterated lavender oil, was prepared in the laboratory. Principal component analysis (PCA), hierarchical clustering ascending (HCA) and K‐means clustering were applied to the FT‐MIR results for qualitative analysis to effectively discriminate between authentic and adulterated essential oils. For quantitative analysis, partial least squares regression (PLSR) was used to develop accurate calibration models for predicting the percentage of adulteration. The results from PCA, HCA and K‐means demonstrated the efficacy of these techniques in detecting adulteration, even at low levels (2%). Calibration models were developed using the PLSR method with different spectral preprocessing techniques to predict the percentage of adulteration, with results indicating that models generated on the raw data and those using MSC (multiplicative signal correction) pre‐processing are optimal. In addition, the use of interval‐partial least squares (IPLS) variable selection techniques (Forward, Backward) improved the predictive accuracy of the models developed by reducing the number of wavelengths used. [ABSTRACT FROM AUTHOR]

ABSTRACT The focus of this research is to use the thermal ablation properties of a Nd:YAG infrared laser to highlight the thermal damage caused by the extinction of the plasma, which leads to the disappearance of the spectra of certain polymers as the laser energy increases. The study involved testing five commonly used polymers: polytetrafluoroethylene (PTFE) also known as Teflon, polyoxymethylene (POM), polyvinyl chloride (PVC), Bakelite, and polyamide. Laser induced breakdown spectroscopy (LIBS) analysis was used to qualitatively analyze the plasma generated from the polymer samples, identifying the excited species present in each of the five polymers. Wavelength dispersive X‐ray fluorescence (WDXRF) analysis of the polymer samples further confirmed the identification of these excited species. The results obtained from the spectra recorded at different laser energies in an air environment showed that the saturation observed in the plasma, induced by increasing laser energy, is not consistently observed for all polymers. This plasma extinction phenomenon in certain polymers is attributed to thermal effects when using an infrared (IR) laser as a heating source. [ABSTRACT FROM AUTHOR]

ABSTRACT Interaction of iron chalcogenides (μ‐Ex)[CpFe(CO)2]2 (E = S; x = 2–4, E = Se, x = 1) with propargyl chloroformate (ClCO2CH2C≡CH) in diethyl ether yielded iron(II) chalcogenopropargylcarbonato complexes CpFe(CO)2ECO2CH2C≡CH (E = S (1), Se (2)). These complexes have been characterized by elemental analysis, UV–Vis, IR, and 1H‐ and 13C{1H}‐NMR spectroscopy and single‐crystal x‐ray diffraction techniques. Further, the suitability of complexes 1 and 2 as CO‐releasing molecules (CORMs) for the administration of carbon monoxide has been studied. CO gas is released upon irradiation of THF solution of these complexes in the presence of hemoglobin. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the dose-dependent brain temperature effects of transcranial photobiomodulation (t-PBM). Thirty adult subjects with major depressive disorder were randomized to three t-PBM sessions with different doses (low: 50 mW/cm2, medium: 300 mW/cm2, high: 850 mW/cm2) and a sham treatment. The low and medium doses were administered in continuous wave mode, while the high dose was administered in pulsed wave mode. A 3T MRI scanner was used to perform proton magnetic resonance spectroscopy (1H-MRS). A voxel with a volume of 30 × 30 × 15 mm3 was placed on the left prefrontal region. Brain temperature (°C) was derived by analyzing 1H-MRS spectrum chemical shift differences between the water (~ 4.7 ppm) and N-acetyl aspartate (NAA) (~ 2.01 ppm) peaks. After quality control of the data, the following group numbers were available for both pre- and post-temperature estimations: sham (n = 10), low (n = 11), medium (n = 10), and high (n = 8). We did not detect significant temperature differences for any t-PBM-active or sham groups post-irradiation (p-value range = 0.105 and 0.781). We also tested for potential differences in the pre-post variability of brain temperature in each group. As for t-PBM active groups, the lowest fluctuation (variance) was observed for the medium dose (σ2 = 0.29), followed by the low dose (σ2 = 0.47), and the highest fluctuation was for the high dose (σ2 = 0.67). t-PBM sham condition showed the overall lowest fluctuation (σ2 = 0.11). Our 1H-MRS thermometry results showed no significant brain temperature elevations during t-PBM administration. [ABSTRACT FROM AUTHOR]

Present investigation deals with the structural and pharmacokinetic properties of hydantoin‐based drug molecules such as phenytoin, mephenytoin, and ethotoin. Hydantoin‐based drugs are widely used as anticonvulsants in the treatment of epilepsy. In this study, optimized structures, and theoretical vibrational wavenumbers of phenytoin, mephenytoin, and ethotoin molecules were determined using Gaussian 09 program with density functional theory (DFT) and B3LYP/6‐311++G(d,p) basis set, vibration mode assignments were performed with the GAR2PED program, and the theoretical results were supported by FTIR and Raman spectroscopy. In addition, thermodynamic parameters, Mulliken charge values, HOMO‐LUMO, natural bond orbital, MEP, hyperpolarizability analyzes of hydantoin‐based molecules were performed. Docking analysis of all molecules with the GABA‐AT receptor, which has an important place in epilepsy studies, were also carried out. Then, the molecular dynamic (MD) simulations of the hydantoin‐based drugs‐GABA‐AT complexes were realized for 50 ns. ADMET profiles of all molecules were determined and presented by parameters of toxicity and drug‐likeness. Additionally, to determine the effects of hydantoin‐based drugs on glioblastoma cells, cytotoxic effects of phenytoin, mephenytoin, and ethotoin were evaluated on U‐87 Human glioblastoma cell line. [ABSTRACT FROM AUTHOR]

The article considers different methods of divertor plasma diagnostics planned for using in the T‑15MD tokamak. Technical problems arising during operation of optical systems in the divertor zone are discussed, including degradation of in-vessel optical elements. The main attention is paid to the conceptual design of the "Passive Spectroscopy in Divertor" diagnostic system. The optical system, including in-vessel mirrors, and methods for protecting its components from the negative effects of plasma are described in detail. Using synthetic diagnostics and numerical simulation methods, the possibility of solving the problem of tomographic reconstruction of the two-dimensional profile of plasma radiation in the T-15MD divertor is demonstrated. Based on the results presented, it was concluded that passive spectroscopy can be used for obtaining data on plasma parameters in the divertor with good spatial resolution, which will make it possible to study the physics of processes and monitor the operation of the T-15MD divertor, including the operation in detachment regime. [ABSTRACT FROM AUTHOR]

In this paper we address two problems associated with data‐limited dynamic spacecraft exploration: data‐prioritization for transmission, and data‐reduction for interpretation, in the context of ESA ExoMars rover multispectral imaging. We present and explore a strategy for selecting and combining subsets of spectral channels captured from the ExoMars Panoramic Camera, and attempt to seek hematite against a background of phyllosilicates and basalts as a test case scenario, anticipated from orbital studies of the rover landing site. We compute all available dimension reductions on the material reflectance spectra afforded by 4 spectral parameter types, and consider all possible paired combinations of these. We then find the optimal linear combination of each pair whilst evaluating the resultant target‐vs.‐background separation in terms of the Fisher Ratio and classification accuracy, using Linear Discriminant Analysis. We find ∼50,000 spectral parameter combinations with a classification accuracy >95% that use 6‐or‐less filters, and that the highest accuracy score is 99.6% using 6 filters, but that an accuracy of >99% can still be achieved with 2 filters. We find that when the more computationally efficient Fisher Ratio is used to rank the combinations, the highest accuracy is 99.1% using 4 filters, and 95.1% when limited to 2 filters. These findings are applicable to the task of time‐constrained planning of multispectral observations, and to the evaluation and cross‐comparison of multispectral imaging systems at specific material discrimination tasks. Plain Language Summary: Specially designed cameras used by Mars rovers can see not just with the red, green and blue colors of trichromatic vision, but through a dozen or so distinct color channels, some of which extend into the near‐infrared. This super‐human color vision allows for the distinction of a greater diversity of materials, such as types of rocks and soils, than 3‐color vision. This extra color information requires extra data, but there is a limit to the data than can be transmitted from Mars back to Earth each day. If only some of these colors can be transmitted, then which should be chosen? And once transmitted, how should these channels be combined and contrast‐stretched to best convey the content of the scene? That is the problem we address in this paper. We have used mathematical methods from linear algebra to efficiently trial >200,000 possible combinations and contrast stretches of the 12 available color channels of the ExoMars rover Panoramic Camera to find the best combination that uses the smallest number of channels, for finding the water‐related mineral hematite at the landing site of the ExoMars rover. We've found that only 2–6 channels are needed for an accuracy of >99%. Key Points: Method for ranking the ability of multispectral channel combinations to separate target from background material reflectance spectraUsed to seek minimal number of spectral channels needed by the ExoMars Rover PanCam multispectral imager to find hematite at Oxia PlanumFind ∼50,000 combinations with >95% accuracy using six‐or‐less channels, and find that >99% accuracy can be achieved with 2 channels [ABSTRACT FROM AUTHOR]

In this review article, the main techniques for spectroscopic studies of gases in field conditions are considered. The issues related to the study of gas emissions from soils and the determination of their concentrations are analysed. The main types of spectroscopy used in portable devices for soil gas analysis, along with their design features and sampling approaches, are provided. Various studies aimed at optimising the operation of devices for analysing gases emitted from the soil, taking into account agronomic, agrochemical, and ecological specifics, are also presented. The effect of using different types of lasers and reflecting elements on the accuracy of optical measurements and the sensitivity to various substances in the gases is analysed. [ABSTRACT FROM AUTHOR]

Introduction The use of functional near-infrared light spectroscopy (fNIRS) may be applied to study cortical responses in children and could offer insight into auditory and speech perception during the early stages of life. Some literature suggests that babies are already able to identify familiar voices at birth, and fNIRS is a non-invasive technique that can be used to study this population. Objective To characterize the cortical responses of infants during their first trimester of life to infant-directed speech using near-infrared light spectroscopy and to verify whether there is a difference in responses when infant-directed speech is performed by their mother compared with an unknown person. Methods Twenty-three children between 0 and 3 months, healthy, without risk indicators for hearing loss, and with results considered normal in the audiological evaluation were tested with near-infrared spectroscopy using infant-directed speech as an auditory stimulus produced by their own mother and by an unknown source. Results Bilateral cortical activation was observed. The responses were present in the temporal, frontal, and parietal regions. Regarding the familiarity aspect, no significant difference was observed for the mother's voice compared with an unknown voice. Conclusion Infant-directed speech has prosodic characteristics capable of activating several cortical regions in the infant's first trimester of life, especially the temporal region. The familiarity effect needs to be better defined for this type of stimulus during this period. [ABSTRACT FROM AUTHOR]

The quantification of pharmaceutical compounds in biological matrices is a critical component of drug development, therapeutic drug monitoring, and pharmacokinetic studies. Over the past decade, significant advances have been made in analytical techniques that enhance the sensitivity, accuracy, and efficiency of these measurements. This comprehensive review explores the recent developments in various analytical methods, including chromatography, mass spectrometry, spectroscopy, and electrochemical techniques, focusing on their application in pharmaceutical analysis. Additionally, emerging trends such as high-throughput screening, miniaturization, and the integration of artificial intelligence (AI) are discussed, highlighting their potential to revolutionize the field. The review also addresses the challenges associated with current methodologies, including matrix effects, the need for extensive sample preparation, and the push towards greener and more sustainable analytical practices. Finally, future directions in the field are proposed, emphasizing the importance of continued innovation to meet the evolving needs of pharmaceutical analysis. [ABSTRACT FROM AUTHOR]

Preparation conditions play a key role in tailoring the properties of ceramic materials, including ferrite, to suit efficient industrial and technological applications. This manuscript is concerned with correlating the structural, spectroscopic, optical, transport, and dielectric properties of nickel zinc ferrite nanoparticles (NZNs) to the sintering temperature as an effective preparation condition controlled through the coprecipitation technique. Techniques for studying the various features of the synthesized compounds include x-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, Fourier-transform infrared spectroscopy, ultraviolet-visible spectroscopy, and the LCR bridge. XRD data showed the as-prepared samples' single-phase inverse spinel structure and an increase in crystallinity with increasing sintering temperature. SEM images show the nanosized range with semi-spherical particles for all the NZN fabricated samples. Moreover, Raman spectroscopy results showed that the four distinct active modes (Eg, F2g(2), A1g(2), and A1g(1)) for the NZN compounds have the same lattice strain tendency. The direct and indirect optical energy gap values (2-3.82) eV of the synthesized compounds span a wide range in the visible and ultraviolet spectrum, making them candidates for optoelectronic applications. In general, sintering temperature plays an outstanding role in increasing the values of some features such as crystallite size, optical energy gap, and electrical conductivity, and correspondingly decreasing other features such as unit cell volume dissociation density, absorption bands, and dielectric parameters. [ABSTRACT FROM AUTHOR]

Microplastics (MPLs) and nanoplastics (NPLs) are smaller particles derived from larger plastic material, polymerization, or refuse. In context to environmental health, they are separated into the industrially-created "primary" category or the degradation derivative "secondary" category where the particles exhibit different physiochemical characteristics that attenuate their toxicities. However, some particle types are more well documented in terms of their fate in the environment and potential toxicological effects (secondary) versus their industrial fabrication and chemical characterization (primary). Fourier Transform Infrared Spectroscopy (FTIR/µ-FTIR), Raman/µ-Raman, Proton Nuclear Magnetic Resonance (H-NMR), Curie Point-Gas Chromatography-Mass Spectrometry (CP-gc-MS), Induced Coupled Plasma-Mass Spectrometry (ICP-MS), Nanoparticle Tracking Analysis (NTA), Field Flow Fractionation-Multiple Angle Light Scattering (FFF-MALS), Differential Scanning Calorimetry (DSC), Thermogravimetry (TGA), Differential Mobility Particle [Sizing] (DMPS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Scanning Transmission X-ray Microspectroscopy (STXM) are reviewed as part of a suite of characterization methods for physiochemical ascertainment and distinguishment. In addition, Optical-Photothermal Infrared Microspectroscopy (O-PTIR), Z-Stack Confocal Microscopy, Mueller Matrix Polarimetry, and Digital Holography (DH) are touched upon as a suite of cutting-edge modes of characterization. Organizations, like the water treatment or waste management industry, and those in groups that bring awareness to this issue, which are in direct contact with the hydrosphere, can utilize these techniques in order to sense and remediate this plastic polymer pollution. The primary goal of this review paper is to highlight the extent of plastic pollution in the environment as well as introduce its effect on the biodiversity of the planet while underscoring current characterization techniques in this field of research. The secondary goal involves illustrating current and theoretical avenues in which future research needs to address and optimize MPL/NPL remediation, utilizing nanotechnology, before this sleeping giant of a problem awakens. [ABSTRACT FROM AUTHOR]

This study describes the physicochemical characterisation of interpenetrating hydrogel networks (IHNs) composed of either poly(hydroxyethylmethacrylate, p(HEMA)) or poly(methacrylic acid, p(MAA)), and Pluronic block copolymers (grades F127, P123 and L121). IHNs were prepared by mixing the acrylate monomer with Pluronic block copolymers followed by free radical polymerisation. p(HEMA)–Pluronic blends were immiscible, evident from a lack of interaction between the two components (Raman spectroscopy) and the presence of the glass transitions (differential scanning calorimetry, DSC) of the two components. Conversely, IHNs of p(MAA) and each Pluronic were miscible, displaying a single glass transition and secondary bonding between the carbonyl group of p(MAA) and the ether groups in the Pluronic block copolymers (Raman and ATR-FTIR spectroscopy). The effect of storage of the IHNs in Tris buffer on the physical state of each Pluronic and on the loss of Pluronic from the IHNs were studied using DSC and gravimetric analysis, respectively. Pluronic loss from the IHNs was dependent on the grade of Pluronic, time of immersion in Tris buffer, and the nature of the IHN (p(HEMA) or p(MAA)). At equilibrium, the loss was greater from p(HEMA) than from p(MAA) IHNs, whereas increasing ratio of poly(propylene oxide) to poly(ethylene oxide) decreased Pluronic loss. The retention of each Pluronic grade was shown to be primarily due to its micellization; however, hydrogen bonding between Pluronic and p(MAA) (but not p(HEMA)) IHNs contributed to their retention. [ABSTRACT FROM AUTHOR]

Luminescent polymer composites based on polystyrene and polycarbonate doped with boron difluoride curcuminoids containing various substituents in the phenyl ring have been synthesized. The effect of substituents, polymer matrix, and luminophore concentration on the spectral properties of the polymer composites has been studied. It has been found that the effect of the electron-donating force of luminophore substituents on the emission characteristics of the films is similar to the effect of solutions. The films doped with luminophores containing alkyl substituents (1a–5a) do not change their emission characteristics upon switching to another polymer matrix, while the 6a-doped composites are characterized by positive solvatochromism. A bathofluoric shift of luminescence with an increase in the luminophore concentration to 0.5% is observed for all the films. It has been found that the 6a-doped films exhibit delayed fluorescence. [ABSTRACT FROM AUTHOR]

Accurate real-time estimation of nutrient concentrations in potato (Solanum tuberosum L.) canopies is crucial for advanced decision support systems in site-specific nutrient management. This study investigated the effectiveness of unmanned aerial vehicle (UAV) based hyperspectral imaging in predicting nitrogen (N), phosphorus (P), potassium (K), and sulfur (S) concentrations in potato plants comparing two sampling types such as petiole/leaves and above-ground biomass (AGB) sampling. Furthermore, this study also investigates the prediction of AGB, total, and marketable yield of two potato cultivars, 'Atlantic' (chipping) and 'Red La Soda' (tablestock). Four UAV flights over experimental sites were made, and hyperspectral imaging sensors (393–995 nm, 273 bands) were conducted, which coincided with the in-field sample collection as ground truth. Data were analyzed using the partial least square regression model after preprocessing and extracting spectra from images. The model showed high accuracy in estimating plant N concentration from petiole/leaf samples (external validation R2 = 0.58; [external validation RMSE = 0.31 × 104 mg kg−1]), as well as for P (0.75 [0.05 × 104 mg kg−1]) and S (0.58 [0.03 × 104 mg kg−1]). Potassium estimation accuracy improved with biomass sampling (0.47 [1.19 × 104 mg kg−1]). Above-ground biomass estimation had higher accuracy for 'Atlantic' (0.75 [1.29 Mg ha−1]) than for 'Red La Soda' (0.57 [1.38 Mg ha−1]). The model accurately estimated total and marketable tuber yields for both cultivars, with variations noted based on flight timing related to the crop stage. Cultivar 'Red La Soda' achieved the highest total yield accuracy on the first (0.76 [3.31 Mg ha−1]) and fourth flights (0.76 [3.31]), while the 'Atlantic' had the highest accuracy on the third flight (0.50 [4.11]). Model outputs, including standardized coefficients and variable importance in prediction, visualizing band contributions to measured parameter predictions are presented. This study concludes that hyperspectral imaging successfully estimates the potato nutrient concentration and predicts the in-season potato yield, which can contribute significantly to the potato management decision support system. However, it underscores the importance of multiyear high temporal data acquisition with variable potato varieties to establish a reliable AGB and yield estimation model to improve performance. [ABSTRACT FROM AUTHOR]

This study presents a case of processing X‐ray computed tomography (CT) data for pork scans using chemometric latent space modeling. The distribution of voxel intensities is shown to exemplify a multivariate, multi‐collinear signal mixture. While this concept is not novel, it is revisited here from a chemometric perspective. To extract meaningful information from such multivariate signals, latent space modeling based on partial least squares (PLS) is an ideal solution. Furthermore, a robust PLS approach is even more effective for latent space modeling, as it can extract latent spaces unaffected by outliers, thereby enhancing predictive modeling. As an example, lean meat percentage is predicted using X‐ray CT data and robust PLS regression. This method is applicable to X‐ray CT quantification analysis, particularly in cases where unclear, erroneous, and outlying observations are suspected in the data. [ABSTRACT FROM AUTHOR]

Attempting to compute the excess Raman spectra, the authors found that the method of spectral normalization greatly influences not only the intensity but also the shape of the excess spectra. We here present a method for the computation of normalized excess Raman spectra that is regarded as thermodynamically consistent. In the presented method, the normalized excess Raman spectra are computed from molar Raman spectra, which cannot be measured directly. It is therefore described how they can be obtained from intensity‐normalized Raman spectra and a regression of mixture Raman spectra. [ABSTRACT FROM AUTHOR]

New nitrobenzyl-pyridyl ether ligands were synthesized by reacting nitrobenzyl bromide (2-, 3- and 4-nitro) and halogen-substituted hydroxy pyridine (2-chloro-3-hydroxy-pyridine, 2-bromo-3-hydroxy-pyridine) compounds in DMF. By interacting the obtained ligands (L1, L3, L4 and L6) with silver (I) nitrate, transition metal complexes were prepared (AgL1, AgL3, AgL4 and AgL6). The structures of the synthesized ligands and complexes were characterized using FTIR, HRMS, 1H-NMR and 13C-NMR spectroscopic techniques. In addition, fluorescence spectra of the ligands (L1-L6) were detected in the presence of different metal cations (Li+, Na+, Mg2+, Al3+, K+, Ca2+, Cr3+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+ and Ag+). In addition, the thermal behavior of all compounds were examined by TGA-DTA methods and the data of silver complexes and ligands were compared. Within the scope of the study, the antibacterial activities of all compounds were investigated against 4 pathogens, 2 of which were plant-borne (Xanthomonas vesicotoria, Clavibacter michiganensis subsp. Michiganensis) and 2 were food-borne (Escherichia coli, Listeria monocytogenes). [ABSTRACT FROM AUTHOR]

This article reviews the spectroscopic principles related to three established satellite-based systems for global greenhouse gas monitoring, namely Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY), Greenhouse Gases Observing Satellite (GOSAT) and Orbiting Carbon Observatory (OCO) series. It reveals that the worldwide endeavor of atmospheric carbon dioxide (CO2) and other greenhouse gas measurements have not only alerted mankind about the climate hazards but also have enriched basic physical science, especially spectroscopy that need more elucidation. This review points out that the technology of remote sensing of trace gases has achieved several radically new dimensions in science research, such as the shift from in situ chemical analysis to distant spectroscopic measurements and development of space-borne hyperspectral observation systems. It has implemented fundamentally new spectroscopic techniques, namely double-pendulum interferometer and imaging spectroscopy, and executed novel statistical procedures for assessing atmospheric radiative absorption. New avenues are opened, such as implementing differential optical absorption spectroscopy from space and assessing solar-induced chlorophyll fluorescence at global level. In brief, this review highlights several new spectroscopic applications of the known physical principles that were conceptualized in course of developing the remote sensing systems for atmospheric CO2 and other greenhouse gases. [ABSTRACT FROM AUTHOR]