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Quantum dots (QDs) are useful for demonstrating the particle-in-a-box (PIB) model utilized in quantum chemistry, and can readily be applied to a discussion of both thermodynamics and kinetics in an undergraduate laboratory setting. Modifications of existing synthetic procedures were used to create QDs of different sizes and compositions (CdS passivated with polymer, and CdSe passivated with oleic acid/ trioctylphosphine). These were investigated by spectroscopy, to which standard 3D PIB mathematical models were applied to determine their effective size. The data were compared to those from other methods for students to see the validity of the PIB model. For CdSe QDs, an empirical formula was applied to the spectroscopic data. In the case of CdS, the synthesized QDs were studied with X-ray diffraction, from which one can also estimate the size of the QDs. Finally, the QDs were utilized as the light-harvesting layer in photovoltaic cells by attachment to a layer of surface-modified titania (TiO[subscript 2]) nanoparticles on conductive glass, and the surface chemistry tested via water contact-angle measurements. The photoresponse of these cells was measured using basic electrochemistry equipment for a selection of QDs, and these results were considered in relation to the light source used for excitation (CdS QDs absorb UV light, and a voltage was only measurable upon exposure to UV light). Students are able to synthesize, characterize, and apply their materials to a functional purpose. Ultimately, students drafted reports in the form of an ACS-style communication, allowing for a tie-in of typical lab reports to real-world journal publications.

Abstract Chirality plays a critical role in the biochemistry of life and often only one enantiomeric series is observed (homochirality). Only a few natural products have been obtained as racemates, e.g. the signalling molecule valdiazen produced by Burkholderia cenocepacia H111. In this study, we investigated the ham biosynthetic gene cluster and discovered that both the enantiomerically pure (R)-fragin and the racemic valdiazen result from the same pathway. This stereodivergence is based on the unusual heterocyclic intermediate dihydrosydnone N-oxide, as evident from gene knockout, stable isotope feeding experiments, and mass spectrometry experiments. Both non-enzymatic racemisation via keto-enol tautomerisation and enzyme-mediated dynamic kinetic resolution were found to be crucial to this stereodivergent pathway. This novel mechanism underpins the production of configurationally and biologically distinct metabolites from a single gene cluster. Our findings highlight the intricate design of an intertwined biosynthetic pathway and provide a deeper understanding of microbial secondary metabolism related to microbial communication.

In this study, a biochar-metal–organic framework (MOF) nanocomposite was synthesized via ball milling to enable the simultaneous extraction of multiple contaminants from wastewater. The Brunauer-Emmett-Teller (BET) analysis revealed a significant increase in surface area after ball milling. SEM-EDS confirmed the successful synthesis, while X-ray diffraction (XRD) and thermogravimetric analysis (TGA) indicated an amorphous structure with thermal stability up to 300 °C. FTIR and XPS analyses identified functional groups such as C=C, C-H, –COOH, C=O, –OH, C-O, and Fe-BTC. Adsorption capacity and binding properties were evaluated using Langmuir and Freundlich isotherms, with the Freundlich model providing a better fit (R2 = 0.9579–0.9913) compared to the Langmuir model (R2 = 0.9239–0.9862). The nanocomposite exhibited maximum adsorption capacities of 74.18–85.69 mgg−1 for heavy metals and 72.99–86.21 mgg−1 for steroidal hormones. Kinetic analysis showed the adsorption process followed a pseudo-second-order model. A leaching test confirmed the nanocomposite’s high stability, making the BC-Fe-BTC nanocomposite a promising material for wastewater treatment applications.

In about twenty years, starting in 1984, Bangalore has become the fourth best "Global Hub of Technological Innovation", according to Business Week. This article reviews the major milestones in Bangalore's development and the interactive roles of government, universities and private entrepreneurs. The author offers a new model: innovation is not a state but a process, comparable to the chemical process of crystal formation and growth.

Abstract Five dimethylamino-based chalcone derivatives (AC) were synthesized and evaluated for their inhibition degree against monoamine oxidase (MAO) enzymes. All AC compounds showed better inhibitory activity against MAO-B than that against MAO-A. AC4 showed the highest inhibitory ability with an IC50 value of 0.020 µM, similar to that of a reference drug safinamide (IC50 = 0.019 µM) against MAO-B, followed by AC1 (IC50 = 0.068 µM) and AC3 (IC50 = 0.083 µM). Substituent -F in ring A (AC4) increased the MAO-B inhibition, followed by -H (AC1), -Br (AC3), and -Cl (AC2). The selectivity index (SI) value of AC4 was high (SI = 82.00) as well as other compounds (44.41 to 98.15). AC4 was found to be a reversible inhibitor as confirmed through analysis using the dialysis method. Interestingly, AC4 was observed to be a noncompetitive MAO-B inhibitor with a rare case and with Ki values of 0.011 ± 0.0036 µM. These experiments confirmed that AC4 is a reversible and potent selective inhibitor of MAO-B. Molecular docking experiments revealed that AC4 showed the highest inhibitory activity with a docking score (-9.510 kcal/mol). A study using molecular dynamics modeling revealed that the protein–ligand complex was more stable. It was observed that AC4 was non-cytotoxic in the study using L929 cell line. In conclusion, compound AC4 shows promise as a MAO-B inhibitor.

Abstract Ten isatin-based hydrazone derivatives were synthesized using two subseries, IA (isatin + acetophenone) and IB (isatin + benzaldehyde), and evaluated for their monoamine oxidases (MAOs) inhibitory activity. All the compounds showed stronger MAO-A inhibition than MAO-B, and the IB series showed more effective MAO-A inhibitory activity than IA series. Compound IB4 most potently inhibited MAO-A (half maximal inhibitory concentration IC50 = 0.015 µM), followed by IB3 (IC50 = 0.019 µM). On the contrary, compound IB3 showed the highest MAO-B inhibition (IC50 = 0.068 µM), followed by IB4 (IC50 = 1.87 µM). Compound IB3 and IB4 had low selectivity indices of 3.68 and 8.50, respectively. Structurally, the methyl group of IA series decreased the inhibition of both MAO-A and MAO-B. Among them, IB3 and IB4 (4-Cl and 4-Br in B-ring, respectively) showed higher MAO-A and MAO-B inhibition than the other substitutions. Inhibition constant Ki values of IB3 and IB4 for MAO-A were 0.0088 and 0.0063 µM, respectively, and those for MAO-B were 0.048 and 0.060 µM, respectively. IB3 and IB4 were competitive, reversible inhibitors of MAO-A and MAO-B. Molecular docking analysis predicted that IB3 and IB4 formed stable hydrogen bonds between Asn181 and the NH atom of isatin in the ligand-protein complex. Dynamic analysis revealed that IB3 and IB4 are stable with both MAO isoforms. These observations suggest IB3 and IB4 are potent and reversible MAO-A and MAO-B inhibitors and both compounds can be used as therapeutic agents for neurological disorders.

Introduction: Carica papaya is an economically important fruit crop belonging to the family Caricaceae. In this study, we assessed the antioxidant potential and mineral element composition of mature and young fruits, as well as leaves, of the ‘Red Lady’ cultivar of C. papaya. Materials and methods: The DPPH free radical scavenging assay and the FRAP assay were used to evaluate the antioxidant activity of the crude methanolic extract and its butanolic fraction from the mature and young fruit parts and leaf of the C. papaya. The mineral elemental composition was analyzed through ICP-MS analysis. Results: DPPH assay showed that butanolic fraction of young leaves (97±1.155%) and seeds (96.33± 0.8819%) exhibited superior antioxidant potential, followed by mature leaves (81.33 ± 1.856%), mature seeds (72.67± 0.8819%), mature pulp (51±1.155%), young pulp (43.67±2.028%), young peel (34.33±1.202%), and mature peel (30±2.309%). Assessment of metal reducing activity using FRAP assay revealed a similar pattern of antioxidant potential as demonstrated by the DPPH assay. The IC-PMS analysis identified eleven elements in both mature and young fruit parts and leaves of the plant. These elements include potassium (K), sodium (Na), magnesium (Mg), manganese (Mn), zinc (Zn), copper (Cu), iron (Fe), calcium (Ca), nickel (Ni), chromium (Cr), and cobalt (Co). In both mature and young parts of the fruit, as well as in young leaves, potassium (33,874.68 ± 0.0013 mg kg-1 to 8365.31 ± 0.00049 mg kg-1) was the most abundant element. It was followed by magnesium (14,255.82 ± 0.000282 mg kg-1 to 474.92 ± 0.00125 mg kg-1) and then calcium (9857.51 ± 0.00049 mg kg-1 to 366.84 ± 0.00088 mg kg-1). However, in mature leaves, magnesium (14,255.82 ± 0.000282 mg kg-1) was the most prevalent, followed by calcium (9857.51 ± 0.00049 mg kg-1). Conclusion: This research revealed the antioxidant and metal-reducing properties of both mature and young C. papaya fruit and leaves. These findings underscore the nutraceutical potential of C. papaya in combating diseases related to oxidative stress. Furthermore, the presence of essential mineral nutrients in both the young and mature fruit and leaves enhances their health benefits.

Atmospheric hydrogen concentrations have been increasing in recent decades. Hydrogen is radiatively inert, but it is chemically reactive and exerts an indirect radiative forcing through chemistry that perturbs the concentrations of key species within the troposphere, including ozone. Using the atmospheric version of the United Kingdom Earth System Model, we analyse the impact of 10% increased surface concentrations of hydrogen on ozone production and loss. We also analyse the impact of this hydrogen in atmospheres with lower anthropogenic emissions of nitrogen oxides (80% and 30% of present-day anthropogenic surface emissions), as this is a likely outcome of the transition from fossil fuels towards cleaner technologies. In each case, we also assess the changes in hydroxyl radical concentration and hence methane lifetime and calculate the net impact on the hydrogen tropospheric global warming potential (GWP). We find that the hydrogen tropospheric GWP100 will change relatively little with decreases in surface anthropogenic NOx emissions (9.4 and 9.1 for our present day and 30% anthropogenic emissions, respectively). The current estimate for hydrogen GWP100 can therefore be applied to future scenarios of differing NOx, although this conclusion may be impacted by future changes in emissions of other reactive species.

The advancement of both porous materials and nanomaterials has brought about porous nanomaterials. These new materials present advantages both due to their porosity and nano-size: small size apt for micro/nano device integration or in vivo transport, large surface area for guest/target molecule adsorption and interaction, porous channels providing accessibility to active/surface sites, and exposed reactive surface/active sites induced by uncoordinated bonds. These properties prove useful for the development of different porous composition types (metal oxides, silica, zeolites, amorphous oxides, nanoarrays, precious metals, non-precious metals, MOFs, carbon nanostructures, MXenes, and others) through different synthetic procedures—templating, colloidal synthesis, hydrothermal approach, sol-gel route, self-assembly, dealloying, galvanostatic replacement, and so—for different applications, such as catalysis (water-splitting, etc.), biosensing, energy storage (batteries, supercapacitors), actuators, SERS, and bio applications. Here, these are presented according to different material types showing the evolution of the structure design and development towards the formation of hierarchical porous structures, emphasizing that the formation of porous nanostructures came about out of the desire and need to form hierarchical porous nanostructures. Common trends observed across these different composition types include similar (aforementioned) applications and the use of porous nanomaterials as templates/precursors to create novel ones. Towards the end, a discussion on the link between technological advancements and the development of porous nanomaterials paves the way to present future perspectives on these nanomaterials and their hierarchical porous architectures. Together with a summary, these are given in the conclusion.

Abstract In materials science, accurately computing properties like viscosity, melting point, and glass transition temperatures solely through physics-based models is challenging. Data-driven machine learning (ML) also poses challenges in constructing ML models, especially in the material science domain where data is limited. To address this, we integrate physics-informed descriptors from molecular dynamics (MD) simulations to enhance the accuracy and interpretability of ML models. Our current study focuses on accurately predicting viscosity in liquid systems using MD descriptors. In this work, we curated a comprehensive dataset of over 4000 small organic molecules’ viscosities from scientific literature, publications, and online databases. This dataset enabled us to develop quantitative structure–property relationships (QSPR) consisting of descriptor-based and graph neural network models to predict temperature-dependent viscosities for a wide range of viscosities. The QSPR models reveal that including MD descriptors improves the prediction of experimental viscosities, particularly at the small data set scale of fewer than a thousand data points. Furthermore, feature importance tools reveal that intermolecular interactions captured by MD descriptors are most important for viscosity predictions. Finally, the QSPR models can accurately capture the inverse relationship between viscosity and temperature for six battery-relevant solvents, some of which were not included in the original data set. Our research highlights the effectiveness of incorporating MD descriptors into QSPR models, which leads to improved accuracy for properties that are difficult to predict when using physics-based models alone or when limited data is available. Graphical Abstract

Despite extensive experimental focus, there remains a notable gap in comprehending the progressive development of these techniques over time. This comprehensive review is dedicated to cataloging the evolution of extraction and analytical methods spanning several decades. In this article, we meticulously traced the development of analytical and extraction techniques. Additionally, we intricately map the periodic discovery of metabolites within guava fruit, aligning them with the chronological utilization of analytical methods. This article results from extensive research and literature analysis to bridge the knowledge gap. Our efforts highlight the advantageous phytochemicals in guava and the diverse extraction techniques available. By encompassing various facets of analytical methods and delving into metabolomics, this review can offer substantial benefits to cultivating future guava varieties. Subsequent sections within this review will serve as a valuable resource, aiding prospective researchers in identifying the most effective extraction and analytical methods for discovering novel metabolites in guava or similar biological samples. Furthermore, through a comprehensive timeline detailing methodological advancements, this review enhances our understanding of the evolutionary path of guava research. Such insights empower researchers to make informed decisions and actively contribute to the continual advancement of the field of research.

Abstract Nine morpholine-derived halogenated chalcone derivatives (MHC1-MHC9) were synthesized, and their inhibitory activity against monoamine oxidase (MAO) was evaluated. MHC5 showed the highest inhibitory activity against MAO-B with an IC50 value of 0.065 μM, followed by MHC7 (IC50 = 0.078 μM) and MHC6 (IC50 = 0.082 μM). The para-F substituent MHC4 was also potent (IC50 = 0.095 μM). The selectivity index values of all the compounds were high for MAO-B over MAO-A, and the values for MHC5 and MHC4 were 66.15 and 80.11, respectively. MHC5 and MHC4 were competitive MAO-B inhibitors with Ki values of 0.024 ± 0.00062 and 0.041 ± 0.0028 μM, respectively. In reversibility tests, the changes in residual activity before and after the dialysis of MHC5 and MHC4 were similar to those of safinamide, a reversible MAO-B reference inhibitor. Additionally, molecular docking and dynamic simulations predicted that the lead molecules MHC5 and MHC4 could strongly bind to the MAO-B active site with docking scores of –10.92 ± 0.08 and –10.64 ± 0.14 kcal/mol, respectively. Additionally, MHC4 and MHC5 exhibited favorable ADME features, including blood–brain barrier permeability. The experiments confirmed that MHC5 and MHC4 are reversible and potent selective inhibitors of MAO-B and are promising candidates for the treatment of neurodegenerative diseases (human health).

This study investigated the accuracy and precision of a commercially available PNT solution that uses DGNSS-SBAS technology. Time and position data were sampled at a frequency of 20Hz during both a short and long trajectory of a simulated controlled dry-land slalom, as well as during a real-world on-water slalom exercise. The primary objective was to assess the positional accuracy, availability, integrity, and service continuity of the PNT solution while evaluating its ability to differentiate between trajectories. Additionally, the simulated results were compared with an on-water real-world slalom test to validate the findings. The results of the controlled dry-land slalom test indicate that the PNT solution provided accurate measurements with an overall mean ± SD Hrms of 0.20 ± 0.02 m. The integrity measures, HDOD and PDOP, were found to be ideal to excellent, with values of 0.68 ± 0.03 and 1.36 ± 0.07, respectively. The PNT solution utilised an average of 20 ± 1 satellites from the constellation, resulting in an accuracy of

Abstract Water contamination has become a global challenge to human survival. Non-biodegradable heavy metal cations and steroid hormones could accumulate in the human body and could result in serious health problems. In this study, we prepared biochar from waste shells of African star apples and modified biochar using a solvent-free ball milling facile method. The X-ray photoelectron spectrometer (XPS) and Fourier transform infrared spectroscopy (FTIR) analysis revealed biochar functional groups in C=C, C–O, and C=O. Brunauer Emmett Teller (BET) was used to determine the surface area, the surface area of ball-milled biochar obtained at 550 °C (BASA550) increased from 174 m2/g to 304 m2/g after modification. The Langmuir and Freundlich adsorption isotherms best described the experimental adsorption data with RL

Abstract Monoamine oxidases (MAOs) regulate neurotransmitters, and changes in their regulation lead to neurogenerative diseases (NDs). Therefore, MAO inhibitors are used to treat NDs. Ferulic acid, a phenolic compound found in various plant species, has been demonstrated to have a variety of biological functions, including anti-inflammatory, anticancer, and neuroprotective effects. In this study, ten ferulic acid hydrazide derivatives (FA1–FA10) were synthesized, and their ability to inhibit monoamine oxidase (MAO) enzymes was tested. Six candidates demonstrated a more pronounced pattern of inhibitory action against MAO-B than against MAO-A. FA3 had the highest inhibitory efficacy in MAO-B inhibition (IC50 value of 1.88 μM), followed by FA9 (2.08 μM). FA3 has a Ki of 1.92 ± 0.73 μM. A reversibility experiment of MAO-B inhibition by FA3 was conducted using dialysis, and the recovery pattern showed FA3 was a reversible MAO-B inhibitor with a similar recovery to safinamide, a reversible reference inhibitor. These results indicate that FA3 is an effective reversible MAO-B inhibitor. In molecular dynamics and docking, FA3 paired with pi-pi stacking helped stabilize the protein ligand in the active site of MAO-B. According to this study, lead compounds can be used as therapeutic agents to treat neurological conditions, such as Parkinson's disease (PD).

Introduction: In breast cancer, the prognostic role of Ki-67 has been comprehensively studied, and its usefulness has been proven. Ki-67 expression has a prognostic and predictive value in both adjuvant therapy response and neoadjuvant settings. However, the inter and the intraobserver variability in manual counting limits the accuracy of scoring Ki-67 and consequently its application in treatment. Aim: To examine four different methods of Ki-67 estimation to find the most reliable, reproducible and time-efficient scoring methods for Ki-67. Materials and Methods: The present cross-sectional study was conducted in the Department of Pathology, Sree Mookambika Institute of Medical Sciences, Nagercoil, Tamil Nadu, India, from May 2023 to August 2023. Ki-67 immunostained slides of 30 trucut biopsies of invasive breast carcinoma were retrieved and analysed by two observers in a blinded manner. The four different methods of analysis of Ki-67 expression carried out were the global method, the hotspot method, the Eye-10 method and the stepwise counting strategy. The parameters included in the present study were the mean age of the study population, the pre/postmenopausal status, the histopathological type of invasive breast carcinoma, Estrogen Receptor (ER), Progesterone Receptor (PR), and Human Epidermal growth factor Receptor 2 (HER2)/neu status, as well as, the interobserver agreement and the mean time taken by the four methods to analyse the Ki-67 expression. Data entry was performed using Microsoft Office Excel 2013, and statistical analysis was conducted using Statistical Package for the Social Sciences (SPSS) software version 20.0. Descriptive statistics for qualitative variables and mean and Standard Deviation (SD) for quantitative variables were used for data analysis. Chi-square tests were used for bivariate analysis with a determined statistical significance of 5% (p-value

Abstract Ten benzimidazole chalcone derivatives were synthesized, and their monoamine oxidase (MAO) inhibitory activity was evaluated. Most compounds showed higher inhibitory activity against MAO-B than MAO-A. Compound BCH2 exhibited an IC50 value of 0.80 μM, thereby showing the most potent inhibition amongst all. In addition, BCH2 showed the highest MAO-B selectivity index (SI) with an SI value of 44.11 compared to MAO-A. Among the substituents, the halogen group showed the best MAO-B inhibition, and the ortho-position of the B ring showed better inhibitory activity than the para-site. In comparison with ortho-substituents, the inhibitory activity increased in the order, -Cl > -Br > -F > -H. BCH2 was found to be a competitive inhibitor of the enzyme with optimum inhibition kinetics, where Ki was found to be 0.25 ± 0.014 μM. In the reversibility experiment, BCH2 showed a recovery pattern after MAO-B inhibition, similar to that of lazabemide. Thus, BCH2 is a potent, reversible, and selective MAO-B inhibitor and has been suggested as a candidate for the treatment of neurological disorders.

Pododactyl radiography is a non-invasive procedure that enables the detection of foot pathologies, as it provides detailed images of structures such as the metatarsus and phalanges, among others. This examination holds potential for employment in CAD systems. Our proposed methodology employs generative artificial intelligence to analyze pododactyl radiographs and generate automatic medical reports. We used a dataset comprising 16,710 exams, including images and medical reports on pododactylys. We implemented preprocessing of the images and text, as well as data augmentation techniques to improve the representativeness of the dataset. The proposed CAD system integrates pre-trained CNNs for feature extraction from the images and Transformers for report interpretation and generation. Our objective is to provide reports describing pododactyl pathologies, such as plantar fasciitis, bunions, heel spurs, flat feet, and lesions, among others, offering a second opinion to the specialist. The results are promising, with BLEU scores (1 to 4) of 0.612, 0.552, 0.507, and 0.470, respectively, a METEOR score of 0.471, and a ROUGE-L score of 0.633, demonstrating the model’s ability to generate reports with qualities close to those produced by specialists. We demonstrate that generative AI trained with pododactyl radiographs has the potential to assist in diagnoses from these examinations.

Cu-doped ZnO nanoparticles (NPs) were synthesised using Rubia cordifolia root extract and their photocatalytic degradation and antimicrobial properties were evaluated. Among all dopant concentrations, UV-VIS analysis of 5 % Cu–ZnO NPs revealed a clean shift towards the visible range with a reduction in the band gap from 3.2 eV for pristine ZnO to 2.98 eV. Formed NPs were identified as wurtzite crystal structure (size of 16.67 nm) having functional group of ZnO, using XRD and FTIR analysis. Highest photocatalytic degradation efficiencies of both Alizarine Red (AZ) (80 %) and Rhodamine B (RhB) (82 %) dyes were by 5 % Cu–ZnO NPs. Statistical modelling and optimization were conducted using Response Surface Methodology (RSM) and Adaptive Neuro-Fuzzy Inference System (ANFIS), resulting in development of models having >90 % predictive accuracy. Furthermore, the biogenic Cu–ZnO nanoparticles exhibits effective antimicrobial properties against both gram-positive (S. aureus) and gram-negative (E. coli) bacteria. The biogenic synthesis approach demonstrated enhanced photocatalytic efficiency and antimicrobial properties, suggesting its potential for environmentally friendly applications.

Chemotherapy is an indispensable tool in medicine where small molecules act as potential cytotoxic, apoptotic, anti-angiogenic and anti-invasive agents targeting cancer cells. Chemotherapeutic agents possessing these multifaceted properties are highly warranted now as the mortality rate is increasing alarmingly. Tetrazole derivatives are well known for their pharmacological activity against various types of cancer progression. Herein, six derivatives of tetrazoles were synthesised by multicomponent reactions (MCR) and assessed their in vitro anticancer effects. The cytotoxic profiling of these compounds demonstrated that these compounds were active against a panel of breast cancer cells with highest anti-proliferative action against MCF-7. Among the six compounds, DTS 3 with a Chlorine atom demonstrated higher anti-proliferative and cytotoxic effects, which was selected for further investigations. Molecular docking and simulation analysis revealed preferential binding affinity of DTS 3 to CDK6;suggesting its likely role as CDK 6 inhibitor. Interestingly, the entire series of compounds were found to be more potent against cells expressing estrogen receptors, suggesting their dependence on ER signaling cascade. Further analysis revealed their potential to exert anti-invasive effects as well, among which DTS 3 possessed maximal anti-proliferative, anti-apoptotic, and anti-invasive properties suggesting its possible potential as a promising multi-faceted anti-cancer agent.

Furocoumarins, a distinct class of coumarins, hold diverse therapeutic potential such as anti-inflammatory, anticancer, antiviral, antidepressant, and more. Focusing on the past seven years, the review highlights the transition metal-free synthesis of furo[3,2-c]coumarin scaffolds. Metal-free responses have gained popularity because of the growing awareness of the need to preserve natural resources and lessen the negative effects of metal usage on the environment. By categorizing techniques into two-component reactions and MCRs, the review provides a structured understanding of these synthetic methodologies.

Ionic liquid based magnetic nanofuids (ILMFs), an important subclass of ‘IoNanofuids’, have promising prospectus in numerous technological fields. Herein, we have investigated on the dielectric response and ac conductance behaviour of 1 wt% iron oxide-based ILMFs synthesized using pyridinium-based ILs viz., 1-Butyl-4-methylpyridinium tetrafuoroborate (A), 1-Butyl-4-methylpyridinium chloride (B), 1-Butyl-4-methylpyridinium bromide (C) and 1-Butylpyridinium bromide (D), and having variable stability. The dielectric permittivity exhibited a strong correlation with temperature and frequency, especially at low frequency ranges. Havriliak-Negami (H-N) function was plotted for all the four ILMFs which demonstrated a complex dielectric behaviour. The complex dielectric responses (in the range between 10−1–107 Hz) of these ILMFs at various frequencies and temperatures showed two relaxation processes following either Debye or non-Debye nature. The ILMF synthesized in B and D were the stablest. In B, two relaxation processes at 104 Hz and 6 × 102 Hz were observed (at 373.15 K), the temperature dependence being much stronger for the second process. Cole-Cole processes are observable in both relaxations. α parameters varied in the range 0.8 – 1.0 and 0.62 – 0.9 for first and second relaxation process respectively and β parameter equal to 1 at all temperature range for both relaxation processes. In ILMF synthesized using D, Debye relaxation with two relaxation processes were observed closer at 9.1 × 103 Hz and 1.1 × 103 Hz. All the α and β parameters were 1 or 0.99 indicating same relaxation time for all molecules. With D having higher anion-cation interaction energy, Debye process could be observed. The alternating current (AC) conductance of these ILMFs tends to increase with increase in temperature as well as frequency of applied field till 105 Hz after which it decreases.

Abstract Filming atomic motion within molecules is an active pursuit of molecular physics and quantum chemistry. A promising method is laser-induced Coulomb Explosion Imaging (CEI) where a laser pulse rapidly ionizes many electrons from a molecule, causing the remaining ions to undergo Coulomb repulsion. The ion momenta are used to reconstruct the molecular geometry which is tracked over time (i.e., filmed) by ionizing at an adjustable delay with respect to the start of interatomic motion. Results are distorted, however, by ultrafast motion during the ionizing pulse. We studied this effect in water and filmed the rapid “slingshot” motion that enhances ionization and distorts CEI results. Our investigation uncovered both the geometry and mechanism of the enhancement which may inform CEI experiments in many other polyatomic molecules.

Polyetheretherketone (PEEK) is an important super engineering plastic utilized in industries owing to its thermal stability and mechanical strength, however, its robustness hinders chemical recycling. Here, the authors report the depolymerization of insoluble PEEK using sulfur nucleophiles via carbon–oxygen bond cleavage and then treatment with organic halides to form various dithiofunctionalized benzophenones and hydroquinone monomers.

Improving the estimates of CO2 sources and sinks over India through inverse methods calls for a comprehensive atmospheric monitoring system involving atmospheric transport models that make a realistic accounting of atmospheric CO2 variability along with a good coverage of ground-based monitoring stations. This study investigates the importance of representing fine-scale variability in atmospheric CO2 in models for the optimal use of observations through inverse modelling. The unresolved variability in atmospheric CO2 in coarse models is quantified by using WRF-Chem (Weather Research and Forecasting model coupled with Chemistry) simulations at a spatial resolution of 10 km × 10 km. We show that the representation errors due to unresolved variability in the coarse model with a horizontal resolution of 1∘ (∼ 100 km) are considerable (median values of 1.5 and 0.4 ppm, parts per million, for the surface and column CO2, respectively) compared to the measurement errors. The monthly averaged surface representation error reaches up to ∼ 5 ppm, which is even comparable to half of the magnitude of the seasonal variability or concentration enhancement due to hotspot emissions. Representation error shows a strong dependence on multiple factors such as time of the day, season, terrain heterogeneity, and changes in meteorology and surface fluxes. By employing a first-order inverse modelling scheme using pseudo-observations from nine tall-tower sites over India, we show that the net ecosystem exchange (NEE) flux uncertainty solely due to unresolved variability is in the range of 3.1 % to 10.3 % of the total NEE of the region. By estimating the representation error and its impact on flux estimations during different seasons, we emphasize the need to take account of fine-scale CO2 variability in models over the Indian subcontinent to better understand processes regulating CO2 sources and sinks. The efficacy of a simple parameterization scheme is further demonstrated to capture these unresolved variations in coarse models.

Abstract Raising the energy density of lithium‐ion batteries (LIBs) through the operation of high‐voltage cathodes presents a challenge in terms of practical use due to electrolyte degradation. Consequently, it is imperative to explore new materials to circumvent this issue. In this study, a combination of tris(trimethylsilyl) phosphite (TMSPi) and lithium difluoro(oxalato)borate (LiDFOB) is presented as film‐forming additives in a conventional LiPF6‐containing carbonate‐based electrolyte solution in high‐voltage LiNi0.5Mn1.5O4‐graphite full cells. At high voltage, TMSPi oxidizes on the LiNi0.5Mn1.5O4 (LNMO) cathode surface prior to the decomposition of electrolyte solvents, promoting the formation of a stable cathode electrolyte interphase (CEI) layer. In tandem, given that LiDFOB has a lower reduction potential than ethylene carbonate (EC), it has the possibility of forming a solid electrolyte interphase (SEI) on the graphite anode surface. Combining the two additives was found to suppress the degradation of the electrolyte to a large extent. Among the investigated concentration of the additives, the combination of 1 wt. % TMSPi and 2 wt. % LiDFOB added to LP40 electrolyte exhibits improved capacity retention of 80 % after 400 cycles at 0.3 C, compared to the electrolyte with no additive with 67 % capacity retention over the same period. Thereby, the combination of TMSPi with LiDFOB provides an improvement for high voltage LIBs.

Halogenated inhibitors showed robust, reversible, and selective monoamine oxidase-B (MAO-B) inhibitory efficacy in candidates that were derived from them. Our team has previously synthesized and assessed a panel of halogenated chalcones and coumarin for the study on MAO-B inhibition. The aim of this study was to build GA-MLR based QSAR models and predictive 3D Pharmacophore models, as well as to investigate the relationship between halogenated derivatives and MAO-B inhibitory activity. The robust statistical significance in the parameter (R2 = 0.78 and Q2 = 0.69) was demonstrated. Best Hypo1 contains one hydrophobic and two aromatic rings. The lead molecule for quantum mechanics was performed, and it was revealed that it would bind to proteins and provide stability. To determine the stability of the ligand-enzyme complex, a thorough molecular dynamics analysis of the lead compounds was accomplished.

Introduction: Group B Streptococcus (GBS) is the leading cause of neonatal sepsis all over the world. Maternal colonisation of GBS in vaginal and anorectal area poses risk for subsequent invasive disease. The prevalence of maternal colonisation varies with geographical, biological and socio-economical factors. Current recommendations consider maternal screening and antibiotic therapy to prevent GBS neonatal disease with a potential of alteration of infant gut flora. Aim: To find out the prevalence, outcome and antimicrobial susceptibility pattern of the GBS colonisation in antenatal women. Materials and Methods: A hospital-based descriptive crosssectional study was conducted in Government Medical College, Kozhikode, Kerala, India, during December 2017 to May 2019 including 300 antenatal women of 35-37 weeks gestational age. Vaginal and rectal swabs were taken and were subjected to microbiological examination and culture. Data analysis was done by Statistical Package for the Social Sciences (SPSS) version 16.0. The Chi-square test and Fisher’s exact test were used wherever applicable and p-value

The reckless use of non-replenishable fuels by the growing population for energy and the resultant incessant emissions of hazardous gases and waste products into the atmosphere have insisted that scientists fabricate materials capable of managing these global threats at once. In recent studies, photocatalysis has been employed to focus on utilizing renewable solar energy to initiate chemical processes with the aid of semiconductors and highly selective catalysts. A wide range of nanoparticles has showcased promising photocatalytic properties. Metal nanoclusters (MNCs) with sizes below 2 nm, stabilized by ligands, show discrete energy levels and exhibit unique optoelectronic properties, which are vital to photocatalysis. In this review, we intend to compile information on the synthesis, true nature, and stability of the MNCs decorated with ligands and the varying photocatalytic efficiency of metal NCs concerning changes in the aforementioned domains. The review discusses the photocatalytic activity of atomically precise ligand-protected MNCs and their hybrids in the domain of energy conversion processes such as the photodegradation of dyes, the oxygen evolution reaction (ORR), the hydrogen evolution reaction (HER), and the CO2 reduction reaction (CO2RR).

The presence of hazardous metal ions or anions in industrial and domestic water may adversely affect the living systems there. Hence their detection is reducing the risk to human and environmental systems. In this study, we investigate the spectroscopical variations of different analytes and the biological performance of two derivatives of carbohydrazide scaffolds. So, we developed two chemosensors 3TCH and BTTCH to detect Cu2+ and F− in an aqueous medium by using photoluminescence spectroscopy (PL). The BTTCH has also sensitively detected the AcO−. Spectral maxima deviations and colour changes in the concentration in concern can serve as indicators of the interaction that was produced. The limit of detection (LOD) was calculated for all the complexes, which all are in lower limits of quantification and the complex 3TCH + F− showed a much lower value of 8.23 × 10−8 M. The binding constants are calculated using the Benesi-Hildebrand equation, 3TCH + F− showed the highest value (K = 9.39 × 10−7M−1) of the association constant, indicating the highest affinity. Additionally, it was investigated whether the chemosensors could be used with common household items like mouthwash and vinegar.

Microorganism contamination of food storage, water treatment, pharmaceuticals, and especially biomedical equipment is a severe problem. Bacteria frequently contaminate permanent implantations after long-term usage. To successfully treat these infections, it is essential to monitor microbial activity and know how it interacts with antibodies in real-time. In this work, a nanocarbon-polymer nanocomposite (ARPD) is successfully developed, and its antibacterial activity against selected microorganisms is successfully validated. Obtained antibacterial results confirm that the photoluminescent ARPD demonstrated outstanding antibacterial action against the microorganism Escherichia coli from the selected group of bacteria. The fluorescent diagnostics and treatments offer exciting possibilities for the luminescence and biocidal activity of nanocomposite produced from ARH-PVDF nanomaterials.

Bacterial infections and antibiotic resistance remain significant contributors to morbidity and mortality worldwide. Despite recent advances in biomedical research, a substantial number of medical devices and implants continue to be plagued by bacterial colonisation, resulting in severe consequences, including fatalities. The development of nanostructured surfaces with mechano-bactericidal properties has emerged as a promising solution to this problem. These surfaces employ a mechanical rupturing mechanism to lyse bacterial cells, effectively halting subsequent biofilm formation on various materials and, ultimately, thwarting bacterial infections. This review delves into the prevailing research progress within the realm of nanostructured mechano-bactericidal polymeric surfaces. It also investigates the diverse fabrication methods for developing nanostructured polymeric surfaces with mechano-bactericidal properties. We then discuss the significant challenges associated with each approach and identify research gaps that warrant exploration in future studies, emphasizing the potential for polymeric implants to leverage their distinct physical, chemical, and mechanical properties over traditional materials like metals.

The National Household Travel Survey (NHTS), conducted by the Federal Highway Administration, has historically been used for documenting personal mobility trends. Current techniques using surveys to collect this data are labor-intensive and difficult to scale. Emerging connected vehicle (CV) data can provide an alternative data source to potentially provide a more scalable method to measure the temporal and spatial usage of passenger vehicles in near real-time. With an impending shift in the automobile industry towards alternative fuel vehicles (AFV), agile monitoring of trip trends is important to help guide state and national investments in AFV infrastructure. This study presents methodologies and visualizations summarizing observed trip characteristics using a sample of more than 500 billion CV records and nearly 1 billion CV trips for December 2022 in the United States. The analysis found very close agreement between trip lengths for internal combustion engine vehicles (ICEV) for CVs and those reported by the 2017 NHTS. Mean trip lengths and trip durations from CVs and NHTS for ICEVs are within 7.8% and 6.6% of each other. The 85th percentile comparison was similarly close, within 0.7% and 8.3%. A comparison of trip trends among states for ICEVs and AFVs as well as US census places and temporal trends for a selection of states, including Indiana, Texas, Wyoming, and California, is provided. The paper concludes that CV data is an important source to monitor trip characteristics across ICEVs and AFVs in near real-time, which will be particularly important to track during the anticipated change to AFVs.