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Molecules with curved architecture can exhibit unique optoelectronic properties due to the concave‐convex π‐surface. However, synthesizing negatively curved saddle‐shaped aromatic systems has been challenging due to the internal structural strain. Herein, we report the facile synthesis of two polyhexagonal molecular systems, 1 and 2, with saddle shape geometry by judiciously varying the aromatic moiety, avoiding the harsh synthetic methods as that of heptagonal aromatic saddle systems. The unique geometry preferences of B, N, and S furnish suitable curvature to the molecules, featuring saddle shape. The saddle geometry also enables them to interact with fullerene C60, and the supramolecular interactions of fullerene C60 with 1 and 2 modify their optoelectronic properties. Crystal structure analysis reveals that 1, with a small π‐surface, forms a double columnar array of fullerenes in the solid state. In contrast, 2 with a large π‐surface produces a supramolecular capsule entrapping two discrete fullerenes. The intermolecular interactions between B, N, S, and the aryl‐π surface of the host and C60 guest are the stabilizing factors for creating these supramolecular structures. Comprehensive computational, optical, and Raman spectroscopic studies establish the charge transfer interactions between B−N doped heterocycle host and fullerene C60 guest. [ABSTRACT FROM AUTHOR]

Background: Patients who suffer from systemic hypertension frequently have peripheral arterial disease (PAD). Ankle brachial index is a simple approach for detecting asymptomatic PAD. PAD is indicated by an ABI of 0.9. PAD predicts a significant cardiovascular risk and is a sign of atherosclerosis. Aim: To study the effect of systemic hypertension on ankle brachial index and to assess the effect duration of hypertension and blood pressure on ankle brachial index. Materials and Method:Present study was a prospective cross-sectional study conducted in Department of general medicine, SreeMookambika Institute of Medical Sciences, Kulasekharam for a period of 8 months. A total of 75 patients with hypertension attending general medicine out-patient department were included in the study. Patient details were recorded which included age, sex, BMI, duration of hypertension, blood pressure and ankle brachial index. Results were analysed using SPSS 20.0 version and the association was tested using Chi square test. Results: Prevalence of asymptomatic PAD was 52%. Of the 39 patients with ABI was =0.9, 28(71.8%) were males and 11(28.2%) were females. Statistically significant association was found between ABI and age, gender, duration of hypertension and BMI. As the systolic and diastolic BP increases the ABI decreased. Conclusion: In patients with high blood pressure, low ABI is a reliable indicator of mortality. The assessment of the overall cardiovascular risk in the hypertensive population may be aided by the diagnosis of PAD in hypertensives. [ABSTRACT FROM AUTHOR]

This paper proposes an Indirect Field Oriented Controlled Dual Stator Multiphase Induction Motor (IFOC-DSMIM) as a traction unit in an Electric Vehicle (EV) for the enhancement of its fuel economy and average loading capacity. The performance of the drive is studied by loading it under standard drive cycles that include free running, acceleration, and braking conditions using the MATLAB/Simulink environment. Its performance analysis is carried out to obtain efficiency curves under the three modes of excitation using a steady-state equivalent circuit approach. Studies on load sharing between the two stators, speed tracking and torque-producing capability of the drive are executed on its dynamic model and the simulation results are depicted. The average energy efficiency of the vehicle with the proposed DSMIM drive system is at least 10% higher than a Single Stator Multiphase Induction Motor (SSMIM) drive under different load percentages. Furthermore, under 75% of rated load conditions the energy efficiency is 20% higher. Thus, the proposed DSMIM configuration promises to provide a sizeable energy saving in the EV system, reducing the energy cost and increasing the driving range. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper rapid development of various voltage sag compensation techniques in DC bus using ultra-capacitors (UCs) provides satisfactory results when compared with required peak power demand for shorter duration. Later, UCs have been used as floating capacitors [1] [2]. Various UCs are available based on internal resistances which also rely on its manufacturing materials, similar to double layer capacitors. Design/methodology/approach: This paper demonstrates UCs based voltage sag compensation at load side under different working modes of hydraulic pack (HP) in an armored fighting vehicle (AFV). The main sources to supply the HP are 24 V, 400 Ahr battery bank and 20 kW main generator. HP is considered to be the highest power load of a system. 2,500 A inrush current was drawn by HP during initial conditions, and also, this system works in both elevation and azimuth mode. Voltage sag has been varied from 15 to 24 V for different modes. But as per the military standard, electrical systems should operate between 18 and 32 V DC. Because of insufficient terminal voltage, required energy cannot be attained and supplied to the loads. The proposed topology compensated the voltage sag and maintains nominal voltage on a DC bus. The devised circuit has been verified under all possible operating loads such as continuous, intermittent and momentary. The same has been simulated using MATLAB/Simulink and was experimentally verified. The minimum voltage maintained in a DC bus is 22.2 V in simulation, while experimentally, it was 24.2 V. Findings: For getting higher percentage of efficiency, secondary energy system configuration, mainly designed for electrical vehicles, is needed. It was implemented and same was tested with the fighting vehicle system[1]. The proposed configuration comprises of bank of an UC and a battery bank. The system was finally implemented in AFVs. Originality/value: The goods vehicles made of UCs can hold very minimum energy because of minimum density of energy. The modified AFV can have minimum charging as well as discharging of rate of energy and, thus, power[3][4]. Thus, the proposed idea of modified vehicle system has influence over significant change in the state of charge. [ABSTRACT FROM AUTHOR]

This work brings in an eco-friendly, smart integrated miniaturized sensor system to determine the temperature of aqueous solution and soil in a more affordable way to yield quality farming, small-scale agricultural farming, greenhouse farming, domestic gardening, and hydroponics. Carbon-Graphite hybrid electrode-based planar disposable sensor strip is used for sensing the temperature over a range of 27 to 50°C. The temperature sensor element is compared to four distinct structures, and the meander geometrical structure is deduced as a result. The temperature sensing element is fabricated utilizing a prudent, efficacious, and inexpensive microfabrication methodology of screen printing. The temperature and resistance characteristics are plotted for the carbon-graphite electrode on PET and paper. The temperature coefficient of resistance is determined to be 1%/°C for PET and 0.8%/°C paper substrate in soil. Test experiment was carried out in water, oven and on field to find out the characteristic equation of study. The temperature sensor strip is integrated with a Wi-Fi SoC-assisted nodeMCU processor that is used in IoT platforms. An app is created using MIT app inventor user interface and is launched on an android smartphone. The app gives the suitable temperature range for sowing seed and germination of the plant growth information. The instantaneous temperature of soil or water is measured, and status information for plant cultivation is also provided by the app. [ABSTRACT FROM AUTHOR]

Simple Summary: In spite of substantial investigation, the biological link between periodontitis and rheumatoid arthritis remains unexplained. This study intended to correlate periodontitis and rheumatoid arthritis gene expression patterns to find shared targets for both the disease. We identified the differentially expressed genes (DEGs) in periodontitis and rheumatoid arthritis. The network was built by integrating DEGs and ranking the genes using GeneMANIA. FINDSITEcomb2.0 was used to find a possible inhibitor for the top-ranked gene. Further, the binding effectiveness and protein-ligand complex stability were then determined by molecular docking and molecular dynamics. The network analysis showed IFI44L as a highly ranking gene implicated in most immunological pathways. A virtual screening of 6507 compounds revealed vemurafenib as the best candidate for the IFI44L target. Molecular docking and molecular dynamics modelling revealed the stability of the IFI44L-vemurafenib complex, which suggest IFI44L is potential target and vemurafenib could be the better candidate to treat both diseases. Objective: Despite extensive research on periodontitis and rheumatoid arthritis, the underlying molecular connectivity between these condition remains largely unknown. This research aimed to integrate periodontitis and rheumatoid arthritis gene expression profiles to identify interconnecting genes and focus to develop a common lead molecule against these inflammatory conditions. Materials and Methods: Differentially expressed genes (DEGs) of periodontitis and rheumatoid arthritis were identified from the datasets retrieved from the Gene Expression Omnibus database. The network was constructed by merging DEGs, and the interconnecting genes were identified and ranked using GeneMANIA. For the selected top ranked gene, the potential inhibitor was searched using FINDSITEcomb2.0. Subsequently, the molecular docking and molecular dynamics were performed to determine the binding efficiency and protein-ligand complex stability, respectively. Results: From the network analysis, IFN-induced protein 44-like (IFI44L) was identified as a top ranked gene involved in most of the immunological pathway. With further virtual screening of 6507 molecules, vemurafenib was identified to be the best fit against the IFI44L target. The binding energy and stability of IFI44L with vemurafenib were investigated using molecular docking and molecular dynamics simulation. Docking results show binding energy of −7.7 Kcal/mol, and the simulation results show stability till 100 ns. Conclusions: The identified IFI44L may represent a common drug target for periodontitis and rheumatoid arthritis. Vemurafenib could be a potent anti-inflammatory drug for both diseases. [ABSTRACT FROM AUTHOR]

This investigation is to find a prolonged or delayed drug release system, exclusively for the treatment of hepatitis‐B to reduce the side effects, which arise when conventional solid dose forms are administered. To pursue this goal, lamivudine‐loaded Eudragit‐coated pectin microspheres have been formulated employing water/oil (W/O) emulsion evaporation strategy. The formulation was optimised using a 34 factorial design. A drug to polymer ratio of 1:2, the surfactant of 1 ml, the volume of 50 ml of processing medium with a stirring speed of 2500 rpm were found to be the optimal parameters to obtain the lamivudine‐loaded Eudragit‐coated pectin microspheres formulation with a high drug entrapment efficiency of 89.44% ± 1.44%. The in vitro release kinetics of lamivudine was a suitable fit to the Higuchi model, indicating a diffusion‐controlled release with anomalous transport. The obtained microspheres were then subjected to different characterisation studies, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X‐ray diffraction (XRD). The results of this study clearly indicate that Eudragit‐coated pectin microspheres could be the promising controlled release carriers for colon‐specific delivery of lamivudine in the presence of rat cecal content. [ABSTRACT FROM AUTHOR]

Liposomes are unique biomolecular, capable of loading both hydrophilic and hydrophobic molecules and delivered into the biological system. Liposomes (L) coated with hyaluronic acid (HA) and chitosan (CS) carrier system was fabricated. Berberine (BER) and doxorubicin (DOX) were encapsulated to enhance drug proliferation and therapeutic effect in lung cancer cells. The FTIR, XRD, SEM, and TEM techniques were carried out for functional group identification, crystallinity, and surface morphology analysis, respectively. In-vitro drug release confirms the sustained release of BER and DOX in various physiological environments. HA-CS@BER&DOX-L has good penetration ability and higher cytotoxicity effect in the A549 cells, and the IC 50 value of HA-CS@BER&DOX-L is 89.19 μg/300 μL. The pure liposome showed a negligible cytotoxicity effect, and the HA-CS@BER&DOX-L could efficiently induce the apoptosis of A549 cells. The cellular uptake analysis of the HA-CS@BER&DOX-L effectively targeted and entered the A549 cells and clearly observed C. elegans images. Hence, the proposed system will be a potential treatment methodology to enhance the cytotoxicity of the A549 cancer cells and be useful to future drug administration methodology development. [ABSTRACT FROM AUTHOR]

Liposomes are unique biomolecular, capable of loading both hydrophilic and hydrophobic molecules and delivered into the biological system. Liposomes (L) coated with hyaluronic acid (HA) and chitosan (CS) carrier system was fabricated. Berberine (BER) and doxorubicin (DOX) were encapsulated to enhance drug proliferation and therapeutic effect in lung cancer cells. The FTIR, XRD, SEM, and TEM techniques were carried out for functional group identification, crystallinity, and surface morphology analysis, respectively. In-vitro drug release confirms the sustained release of BER and DOX in various physiological environments. HA-CS@BER&DOX-L has good penetration ability and higher cytotoxicity effect in the A549 cells, and the IC 50 value of HA-CS@BER&DOX-L is 89.19 μg/300 μL. The pure liposome showed a negligible cytotoxicity effect, and the HA-CS@BER&DOX-L could efficiently induce the apoptosis of A549 cells. The cellular uptake analysis of the HA-CS@BER&DOX-L effectively targeted and entered the A549 cells and clearly observed C. elegans images. Hence, the proposed system will be a potential treatment methodology to enhance the cytotoxicity of the A549 cancer cells and be useful to future drug administration methodology development. [ABSTRACT FROM AUTHOR]

External stimuli‐responsive luminogens have attracted a lot of attention in the recent years owing to their potential applications in various fields such as sensing, bio‐probes, and optical devices. In this work, the design and synthesis of a new class of external stimuli‐responsive anthracene based fluorescent bis‐(anthryl)boryl anilines 1 and 2 are disclosed. The electronic and optical properties of these compounds are fine‐tuned by varying the amine donor strength. Using steady‐state and time‐resolved photoluminescnece studies in both solution and condensed state together with computational studies (both ground and excited state), it is established that both 1 and 2 exhibit molecular motion dependent emission characteristics. Owing to their molecular conformational flexibility and inherent charge transfer characteristics, 1 and 2 show intriguing optical features such as aggregation induced emission enhancement, viscochromism, temperature sensing, and mechanoluminescence as compared to structurally rigid tris(9‐anthryl)boron without amine donor moieties. These unique properties of 1 and 2 are utilized for detecting local viscosity and temperature sensing over a wide range from 190–300 K. Compound 2 emits pure white light ((Commission internationale de l'éclairage) CIE 0.33, 0.33) at 250 K. [ABSTRACT FROM AUTHOR]

Solid‐state luminescence of organic dyes is an elusive frontier, and understanding and designing solid‐state stimuli‐responsive materials is not trivial. "Mechanoluminescence" (ML) or "triboluminescence" (TL), which is associated with fracture or force‐initiated luminescence from a material, is currently attracting new interest. Fracturing the surfaces of organic crystals ordered in noncentrosymmetric space groups can electronically excite the surface and neighboring molecules through piezo‐ or pyroelectric effects, and this can result in luminescence when the molecules relax back to their ground states. The combined duration of these two consecutive phenomena leads to force‐generated luminescence or TL. Although TL has been known for a very long time, examples of TL‐active materials are scarce, but are increasing as synthetic and characterization procedures develop. The question is now whether the relatively rare phenomenon of TL needs to be reevaluated to obtain a broader understanding of the subject. [ABSTRACT FROM AUTHOR]

Solid‐state luminescence of organic dyes is an elusive frontier, and understanding and designing solid‐state stimuli‐responsive materials is not trivial. "Mechanoluminescence" (ML) or "triboluminescence" (TL), which is associated with fracture or force‐initiated luminescence from a material, is currently attracting new interest. Fracturing the surfaces of organic crystals ordered in noncentrosymmetric space groups can electronically excite the surface and neighboring molecules through piezo‐ or pyroelectric effects, and this can result in luminescence when the molecules relax back to their ground states. The combined duration of these two consecutive phenomena leads to force‐generated luminescence or TL. Although TL has been known for a very long time, examples of TL‐active materials are scarce, but are increasing as synthetic and characterization procedures develop. The question is now whether the relatively rare phenomenon of TL needs to be reevaluated to obtain a broader understanding of the subject. [ABSTRACT FROM AUTHOR]

Reported herein are the synthesis, structure, and intriguing optical characteristics of four new polyaromatic aminoboranes (1–4) bearing dimesitylboron (Mes2B) as electron-accepting unit(s) and diphenylamine (Ph2N) as electron-donating unit(s). These compounds are strongly fluorescent in the solid state. Crystalline samples of 1 and triarylborane-decorated aminoboranes 3 and 4 were found to be blue emitters in the solid state. Compounds 1 and 2 showed aggregation-induced emission (AIE) and aggregation-induced emission color switching, respectively, while 3 and 4 exhibited aggregation-induced emission enhancement. Compounds 1 and 2 showed fascinating mechanofluorochromism upon grinding, and such fluorescence changes are due to a crystalline–amorphous phase transition, as confirmed by powder X-ray diffraction studies (PXRD). Interestingly, a ground sample of 2 was found to be stable and did not revert back upon removal of external stress even after the sample was kept over a long period of time under ambient conditions (more than 6 months). “IPC” was written on a substrate of 2, and the part that was touched showed fluorescence different from the rest of the substrate, which could be erased by heating, demonstrating its capability for rewritable data storage devices. The effect of steric and electronic factors on the optical properties of molecules was corroborated by DFT computational studies. [ABSTRACT FROM AUTHOR]

The design, synthesis, and characterization of a series of thiazole-appended boron-dipyrromethene (BODIPY) derivatives 1- 4 is reported. The fluorescence emission colors of 1- 4 were fine-tuned by modulating the dihedral angle between BODIPY and thiazole by judiciously varying the number of methyl substituents on both the BODIPY and thiazole moieties. Compounds 1 and 2 with fewer methyl substituents on the BODIPY core showed a large Stokes shift (≈110 nm) relative to derivatives 3 and 4 with more methyl substituents. In addition, the optical properties of 1 and 2 are sensitive to the pH of the medium. The experimentally observed results were corroborated with theoretical calculations. [ABSTRACT FROM AUTHOR]

Triarylborane-A2H2 (1) and triarylborane-Zn-A2H2 porphyrins (2) have been synthesized by acid catalyzed condensation of 4-dimesitylboryl-benzaldehyde and dipyrromethane under ambient conditions. Compounds 1 and 2 showed multiple emission bands upon excitation at the triarylborane dominated absorption region (350 nm). Detailed experimental and computational studies show that the multiple emission features of 1 and 2 arise as a result of a partial energy transfer from the donor (triarylborane) to the acceptor (porphyrin) moieties. Compounds 1 and 2 showed very high selectivities towards fluoride ions compared to other competing anions. [ABSTRACT FROM AUTHOR]

The goal of this study was to assess the possibility of reducing chemical fertilizer application through introduction of microbial inoculants for the cultivation of chilly. The microbial inoculants used were Funneliformis mosseae and Bacillus sonorensis as they revealed strong synergistic relationships and significant improvement of growth, yield and nutrition content of chilly under pot culture studies. Microplot experiment was conducted with selected microbial consortia with varying levels of chemical fertilizers in order to reduce the recommended level of chemical fertilizers for chilly cultivation. The results obtained from the microplot experiment suggested that inoculation with microbial consortia increased plant growth, dry weight of shoot, fruit yield and nutrient concentration. The results also brought out that 50% of recommended NPK fertilizer can be reduced through inoculation with microbial consortia with no adverse effect on growth, nutrition and yield of chilly. The large scale field trial conducted at farmer’s field validated the results obtained in the microplot experiment. The soil enzyme activities and soil organic carbon were also more in microbial consortia +50% NPK treatment. Thus the results conclusively brought out that the application of chemical fertilizer to chilly crop can be reduced by 50% which in turn will improve soil health and reduce environmental pollution. [ABSTRACT FROM AUTHOR]

In recent times, luminescent materials with tunable emission properties have found applications in almost all aspects of modern material sciences. Any discussion on the recent developments in luminescent materials would be incomplete if one does not account for the versatile photophysical features of boron containing compounds. Apart from triarylboranes and tetra-coordinate borate dyes, luminescent materials consisting of boron clusters have also found immense interest in recent times. Recent studies have unveiled the opportunities hidden within boranes, carboranes and metalloboranes, etc. as active constituents of luminescent materials. From simple illustrations of luminescence, to advanced applications in LASERs, OLEDs and bioimaging, etc., the unique features of such compounds and their promising versatility have already been established. In this review, recent revelations about the excellent photophysical properties of such materials are discussed. [ABSTRACT FROM AUTHOR]

Luminescent organic materials have attracted significant attention in recent times owing to their opportunities in various functional applications. Interestingly, unlike fluorescence, opportunities hidden within the phosphorescence properties of organic compounds have received considerably less attention even until last few years. It is only in the second decade of the 21st century, within a time span of less than last 5 years, that the concepts and prospects of organic compounds as phosphorescent materials have evolved rapidly. The previously perceived limitations of organic compounds as phosphorescent materials have been overcome and several molecules have been designed using old and new concepts, such as heavy atom effects, matrix assisted isolation, hydrogen bonding and halogen bonding, thereby gaining access to a significant number of materials with efficient phosphorescent features. In addition, significant improvements have been made in the development of RTP (room temperature phosphorescent) materials, which can be used under ambient conditions. In this review, we bring together the vastly different approaches developed by various researchers to understand and appreciate this recent revolution in organic luminescent materials. [ABSTRACT FROM AUTHOR]

Synthesis and crystal structures of three porphyrin-based polyfunctional Lewis acids 1- 3 are reported. Intermolecular HgCl ⋅⋅⋅HgCl (linear and μ-type) interactions in the solid state of the peripherally ArHgCl-decorated compound 3 lead to a fascinating 3D supramolecular architecture. Compound 3 shows a selective fluorescence quenching response to picric acid and discriminates other nitroaromatic-based explosives. For the first time, an electron-deficient polyfunctional Lewis acid is shown to be useful for the selective detection and discrimination of nitroaromatic explosives. The Stern-Volmer quenching constant and detection limits of compound 3 for picric acid are the best among the reported small-molecular receptors for nitroaromatic explosives. The electronic structure, Lewis acidity, and selective sensing characteristics of 3 are well corroborated by DFT calculations. [ABSTRACT FROM AUTHOR]

The interaction of a Lewis acid with a Lewis base results in the formation of a Lewis acid-base adduct. Understanding Lewis acids and bases is central to conceptualizing chemical interactions and constitutes a major portion of metal-ligand chemistry. Sterically encumbered/constrained Lewis pairs cannot form acid-base adducts, but such 'Frustrated Lewis Pairs' (FLPs), with their unquenched electronic demands can be elegantly used to simultaneously react with a third species, resulting in unusual reactivity of small molecules. Such unusual reactions, explored only in the last few years, have found several applications, e.g., heterolytic splitting of H, activation of small molecules (CO, NO, etc.). FLPs have opened new opportunities in synthetic chemistry, covering organic, main group as well as transition metal chemistry. The design strategies adopted for FLP systems and their unique reactivity are discussed here. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Full-color emissive organic materials have attracted significant attention in recent years as key components in display and lighting devices based on OLEDs. An ideal white-light emitter demands simultaneous emission of red, green and blue with nearly similar distribution of intensities covering the entire region of visible spectra. However, the design of such white-light emitters is not straightforward. Mixing several emitters is seldom successful owing to the negative effects of intermolecular interactions and energy transfer processes. Nonetheless, these fundamental questions have been addressed in recent times by several research groups of vastly different expertise leading to a considerable progress in the field of organic white-light emitters. The designs cover a large area of the chemistry ranging from frustrated energy transfer to simple protonation or from designed self-assembly to simple mixing of materials. In this review, the concepts and rational approaches underlying the design of white-light emissive organic materials are described. [ABSTRACT FROM AUTHOR]

Glucocorticoids are associated with immunosuppression and neuropsychiatric complications. We describe the case of a carcinoid patient with Cushing's syndrome (CS) and neurocognitive impairment due to ectopic ACTH production who developed sepsis and died because of his family's decision to withdraw antibiotic treatment. This report is presented to illustrate the importance of advanced-care planning in patients with CS. [ABSTRACT FROM AUTHOR]

The article focuses on developments in boron and its applications. Topics include emergence of Frustrated Lewis acids containing electron-deficient boron centres and their applications in catalysis; application of boron in medicine such as boron-neutron-capture-therapy; and significance of vacancies and the bending of the overall boron structure for stability of boron cluster.

Three new NPI-BODIPY dyads 1- 3 (NPI=1,8-naphthalimide, BODIPY=boron-dipyrromethene) were synthesized, characterized, and studied. The NPI and BODIPY moieties in these dyads are electronically separated by oxoaryl bridges, and the compounds only differ structurally with respect to methyl substituents on the BODIPY fluorophore. The NPI and BODIPY moieties retain their optical features in molecular dyads 1- 3. Dyads 1-3 show dual emission in solution originating from the two separate fluorescent units. The variations of the dual emission in these compounds are controlled by the structural flexibilities of the systems. Dyads 1- 3, depending on their molecular flexibilities, show considerably different spectral shapes and dissimilar intensity ratios of the two emission bands. The dyads also show significant aggregation-induced emission switching (AIES) on formation of nano-aggregates in THF/H2O with changes in emission color from green to red. Whereas the flexible and aggregation-prone compound 1 shows AIES, rigid systems with less favorable intermolecular interactions (i.e., 2 and 3) show aggregation-induced quenching of emission. Correlations of the emission intensity and structural flexibility were found to be reversed in solution and aggregated states. Photophysical and structural investigations suggested that intermolecular interactions (e.g., π-π stacking) play a major role in controlling the emission of these compounds in the aggregated state. [ABSTRACT FROM AUTHOR]

Systematic structural perturbation has been used to fine-tune and understand the luminescence properties of three new 1,8-naphthalimides (NPIs) in solution and aggregates. The NPIs show blue emission in the solution state and their fluorescence quantum yields are dependent upon their molecular rigidity. In concentrated solutions of the NPIs, intermolecular interactions were found to quench the fluorescence due to the formation of excimers. In contrast, upon aggregation (in THF /H2O mixtures), the NPIs show aggregation-induced emission enhancement (AIEE). The NPIs also show moderately high solid-state emission quantum yields (ca. 10-12.7 %). The AIEE behaviour of the NPIs depends on their molecular rigidity and the nature of their intermolecular interactions. The NPIs 1- 3 show different extents of intermolecular (π-π and CH⋅⋅⋅O) interactions in their solid-state crystal structures depending on their substituents. Detailed photophysical, computational and structural investigations suggest that an optimal balance of structural flexibility and intermolecular communication is necessary for achieving AIEE characteristics in these NPIs. [ABSTRACT FROM AUTHOR]

Two new dicyanovinyl (DCV) functionalized triarylboranes (Mes2B-π-spacer-DCV, for 1: π-spacer = C6H4, for 2: π-spacer = 2,3,5,6-tetramethyl-phenyl) are reported. The molecular structures of 1 and 2 are similar except for the spacer which connects the boryl and DCV units. This small structural perturbation induces drastic changes in the optical properties of 1 and 2. Compound 2 shows weak dual fluorescence emission in nonpolar solvents and a stronger emission in polar solvents. Compound 1 is weakly fluorescent in polar environments but shows an intense single luminescence peak in less polar environments. Compound 1 exhibits a turn-off fluorescence response for both fluoride and cyanide: in contrast, 2 shows a turn on fluorescence response for both anions with different fluorescence signatures. The NMR titration studies reveal that for compound 2, fluoride binds to the boron centre and cyanide binds to the DCV unit. For compound 1, the fluoride ion binds to the boron center, whereas the CN- binds to both the Ar3B and DCV units. [ABSTRACT FROM AUTHOR]

Facile synthesis of triad 3 and tetrad 4 incorporating -B(Mes)2 (Mes = mesityl (2,4,6-trimethylphenyl)), boron dipyrromethene (BODIPY), and triphenylamine is reported. Introduction of two dissimilar acceptors (triarylborane and BODIPY) on a single donor resulted in two distinct intramolecular charge transfer processes (amine-to-borane and amine-to-BODIPY). The absorption and emission properties of the new triad and tetrad are highly dependent on individual building units. The nature of electronic communication among the individual fluorophore units has been comprehensively investigated and compared with building units. Compounds 3 and 4 showed chromogenic and fluorogenic responses for small anions such as fluoride and cyanide. [ABSTRACT FROM AUTHOR]

A facile synthetic route for a new class of organoborane compounds (Mes)2B-arene-acacH and (Mes)2Barene- acacBF2 (Mes = mesityl and arene = C6H4 or C6Me4) is reported. The new dyads exhibit intriguing photophysical properties. A small structural change in spacer connecting the two chromophores leads to fine tuning of photophysical properties. The dyad containing 2,3,5,6-tetramethyl phenyl spacer acts as a selective "turn-on" chemodosimetric sensor for cyanide ion. Steric crowding around the boron centre significantly alters anion binding events. From NMR titration studies it is established that fluoride and cyanide follow different binding mechanisms which lead to intriguing optical properties in the reported probes. [ABSTRACT FROM AUTHOR]

Highlights: [•] New constitutional isoelectronic BODIPY isomers were synthesized and studied. [•] The effect of conformational changes was evident from their optical profiles and change in 19F NMR spectra. [•] Solution state behaviors were straightforward, compound 3 showed more fluorescence quantum yield followed by 2 and then 1. [•] The most flexible isomer does not show π–π stacking interactions in the solid state. [ABSTRACT FROM AUTHOR]

Epilepsy prevails to be a neurological disorder in anticipation of safer drugs with enhanced anticonvulsant efficacy as presently available drugs fails to offer adequate control of epileptic seizures in about one-third of patients. The objective of this study was to evaluate the effect of Trichosanthes tricuspidata methanolic extract (TTME) against epilepsy mediated oxidative stress in pilocarpine induced mice. Intraperitonial administration of pilocarpine (85 mg/kg) induced seizure in mice was assessed by behavior observations, which is significantly ( p < 0.05) reduced by TTME (100 and 200 mg/kg; i.p) in a dose dependant manner, similar to diazepam. Seizure was accompanied by significant increase in lipid peroxidation and the hippocampal nitrite content in pilocarpine group when compared with control. Moreover, the antioxidant enzymes superoxide dismutase, catalase and glutathione levels were decreased in pilocarpine administered groups. TTME administration attenuated oxidative damage as evident by decreased lipid oxidative damage and nitrite-nitrate content and restored the level of enzymatic antioxidant defenses in hippocampus. Involvement of free radicals during epilepsy is further confirmed by histopathological analysis which showed the loss of neuronal cells in hippocampus CA1 and CA3 pyramidal region. Our findings strongly support the hypothesis that TTME has anticonvulsant activity accompanied with the strong antioxidant potential plays a crucial role in reducing the oxidative stress produced by seizure. [ABSTRACT FROM AUTHOR]

Objective: To evaluate chemical constituents, in vitro antioxidant and antimicrobial potential of Caryota urens L. Methods: Qualitative analysis of crude extract of C. urens was carried out by gas chromatography mass spectrometry (GC-MS) method and their in vitro antioxidant activity was evaluated using DPPH, ABTS, reducing power and nitric oxide scavenging assays. Antimicrobial activity was determined by disc diffusion method. Results: GCeMS analysis showed the presence of fatty acids, aliphatic, aromatic and phenolic acids. The antioxidant activity of immature fruit and leaf extracts yielded high activity when compared to the fruit skin. The fruit skin and immature fruit of C. urens exhibited strong antibacterial activity against the tested pathogens (Escherichia coli, Vibrio cholerae, Salmonella typhii, Staphylococcus aureus and Shigella flexneri) when compared to leaf. Conclusion: In our results, we suggest that C. urens extracts have strong antioxidant and antimicrobial potential. The identified bioactive compounds of C. urens could be attributed to antioxidant and antimicrobial property. [ABSTRACT FROM AUTHOR]

The article reports on a study about the possible formation of a boron-boron triple bond with only three valence electrons. It says that boron normally resists the development of multiple bonding due to its highly electron-deficient nature. It explores the reactivation of a boron-boron triple bond and how it redefines the fundamental understanding of chemical bonding.

A hybrid electro thermal microactuator is designed and its analytical model is developed. An existing hot and cold beam actuator is added with a gold layer of 0.5 μm thickness, so that the performance of the hybrid electro thermal actuator is improved. The analytical model is validated by comparing the results with 3D finite element model. Further the device is fabricated using SOIMUMPs process and characterized to validate the proposed analytical model. The shape of cold beam is also modified such that it improves the displacement. The results obtained from analytical and experimental models are in good agreement. [ABSTRACT FROM AUTHOR]

Optically active Lewis acids and Lewis pairs were synthesized and characterized by multinuclear NMR, UV/Vis spectroscopy and elemental analysis. Optical rotation measurements were carried out and the absolute configuration of the new chiral molecules confirmed by single crystal X-ray diffraction. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Objectives: The present work was carried out to investigate the free radical scavenging activity of the ethanol extract of C. halicacabum leaves (EECH), to study its antioxidant properties and anti-rheumatic effects in Wistar rats with CFA-induced arthritis, and to profile the phenolic components thereof by LC-MS/MS. Methods: The free radical scavenging activities of the extract was evaluated by NO and superoxide anion scavenging assays. Arthritis was induced to the albino Wistar rats by CFA. Fifteen days after CFA induction, arthritic rats received EECH orally at the doses of 250 and 500 mg/kg daily for 20 days. Diclofenac sodium was used as reference standard. EECH is subjected to LC-MS/MS analysis for the identification of phenolic compounds. Results: The IC value of the EECH to scavenge the NO and superoxide radicals are 83 and 60 μg/ml respectively. Ultrasonography and histology images of hind limb in EECH treated groups confirmed the complete cartilage regeneration. The LC/MS/MS analysis indicated the presence of anti-inflammatory compounds luteolin-7- O-glucuronide, apigenin-7- O-glucuronide and chrysoeriol. Conclusion: These findings lend pharmacological support to the reported folkloric use of C. halicacabum in the treatment and management of painful, arthritic inflammatory conditions. [ABSTRACT FROM AUTHOR]

New 18-membered cyclotriphosphazene-containing macrocycles 7-10 were obtained by 1 + 1 condensation reaction of [dispiro-N3P3(C12H8O2)2((N(Me)N=CH)2 N4C20H26)] (2) with N,N′-dimethyl-ethylenediamine-1,4-diyldimethylenebis(4-methyl-2-formylphenol) (3), N,N′-dimethyl-ethylenediamine-1,4-diyldimethylenebis(4,5-dimethyl-2-formylphenol) (4), N,N′-dimethyl-ethylenediamine-1,4-diyldimethylenebis(5-chloro-2-formylphenol) (5) and N,N′-dimethyl-ethylenediamine-1,4-diyldimethylenebis(5-bromo-2-formylphenol) (6), respectively. [ABSTRACT FROM AUTHOR]

The reaction of [n-BuSn(O)OH]nand 9-hydroxy-9-fluorenecarboxylic acid in the presence of p-X-C6H4-OH (X = F, Br) afforded hydroxyl-rich hexameric organostannoxane prismanes. The crystal structures of these prismanes reveal guest-assisted supramolecular structures. Self-assembly of these compounds on a mica surface affords organooxotin nanotubules. [ABSTRACT FROM AUTHOR]

Disease-related stress associated with infection was investigated in 16 male, yearling Murrah buffaloes. The animals were randomly assigned to one of four groups. Animals in groups 1 and 2 were vaccinated subcutaneously with 4.8 mg of excretory-secretory antigen (group 1) or 1300 μg infection-specific antigen (group 2), in three doses. Subsequently, all the animals in groups 1, 2 and 3 were infected orally with 800 viable metacercariae (bubaline origin) on week 6 of the experiment. The animals in group 4 served as healthy controls. The clinical progress of the disease with respect to the adrenocortical response to infection was assessed periodically. The infected animals in group 3 developed characteristic signs of the disease and had the highest in situ fluke population (mean [se] 331.8 [19.5] ). One of the four animals in group 3 died on day 110 postinfection (PI). Animals that had been immunised before infection (groups 1 and 2) acquired adequate levels of immunity, were comparatively healthier and had significantly lower (P<0.05) fluke populations (mean [se] 194.3 [11.8] in group 1 and 164.5 [9.2] in group 2). Throughout the course of the disease, the group 3 animals had significantly higher cortisol levels than those in groups 1 and 2 (P<0.01) from week 4 PI onward. Although animals in the immunised groups (groups 1 and 2) had increased hormone levels, they were not significantly different from those in the control animals in group 4. Cortisol levels were higher during the early prepatency phase (weeks 1 to 6 PI) than during the late prepatency and/or patency phases of the disease. Cortisol levels in the healthy control animals in group 4 remained within the normal range. [ABSTRACT FROM PUBLISHER]

The article discusses the recovery of coordinated borinium cation. Topics discussed include the discoveries on the developments of the chemistry of boron, the structures of born and their compounds and its Lewis acidic nature. Also emphasized is the absence of any solvent coordination on boron atom even in its solution state.

A series of diboradiferrocenes with different aryl substituents was prepared through reaction of B,B-dichlorodiboradiferrocene 2 with arylcopper and Grignard reagents. The mesityl and pentafluorophenyl derivatives, 3–Mes and 3–Pf, were fully characterized by multinuclear NMR, MALDI-TOF mass spectrometry and X-ray crystallography, and their electronic structure was examined by UV-visible spectroscopy and cyclic voltammetry. A comparison of the data for 3–Mes and 3–Pf with those of the parent compound 3–Ph revealed the importance of electronic and steric effects of the substituents on the electronic structure of the compounds and ultimately the degree of electronic interaction between the two ferrocene moieties. An unusually large redox splitting of ΔE = 703 mV was determined from the cyclic voltammogram of 3–Pf. [ABSTRACT FROM AUTHOR]

The binding behavior of the bifunctional Lewis acid (η 5-C 5H 5Fe) 2[μ-(C 5H 3(BPh)) 2] ( 3) toward different pyridine derivatives as the Lewis base has been investigated. The 1:1 and 1:2 adducts, 3·D and 3·D 2(donor, D = 4- tert-butylpyridine ( tBupy) and 4-dimethylaminopyridine (DMAP)), were obtained by low-temperature crystallization or slow solvent evaporation techniques. The complexes were fully characterized by multinuclear NMR, IR, and elemental analysis. Single-crystal X-ray diffraction data were collected for the 1:1 adduct with DMAP and for both 1:2 adducts, and the marked structural changes upon pyridine binding are discussed in detail. In solution, the 1:2 adducts were found to readily undergo dissociation with formation of the 1:1 adducts as the dominant species at room temperature. Variable-temperature NMR and UV−visible titration studies demonstrate that the first binding process is more than 5 orders of magnitude more favorable than the second binding process. [ABSTRACT FROM AUTHOR]

Abstract: This review deals with the recent developments in the design, assembly and utility of cyclophosphazene-based ligands. The reactive periphery of the chlorocyclophosphazenes allows their ready elaboration into a variety of multi-site coordination ligands such as pyrazolylcyclophosphazenes, cyclophosphazene hydrazides, pyridyloxycyclophosphazenes, pyridylaminocyclophosphazenes, phosphine-containing cyclophosphazenes, etc. The versatile coordination behavior of these diverse ligand systems is described. The extension of the small-molecule chemistry to the more complex polymer systems, which has been done in a few systems, is described. The utility of aminocyclophosphazenes for preparing multi-metallic architectures is also discussed. [Copyright &y& Elsevier]

The cyclophosphazene hydrazides N3P3(N(Me)NH2)6(1), spiro-N3P3(C12H8O2)(N(Me)NH2)4(2), and dispiro-N3P3(C12H8O2)2(N(Me)NH2)2(3) have been readily elaborated by a click synthesis involving condensation with pentafluorobenzaldehyde to afford the fluorine-rich cyclophosphazene hydrazones N3P3(N(Me)NCHC6F5)6(4), spiro-N3P3(C12H8O2)(N(Me)NCHC6F5)4(5), and dispiro-N3P3(C12H8O2)2(N(Me)NCHC6F5)2(6) in excellent yields. The molecular and crystal structures of 4−6are reported. The crystal structures of 4−6reveal a rich interplay of various intermolecular secondary interactions generating novel supramolecular architectures. The dependence of the molecular symmetry on the eventual supramolecular structures is also revealed. The crystal structure of 6shows the selective entrapment of guest dioxane molecules. [ABSTRACT FROM AUTHOR]

Abstract: The reactions of bis(pyrazol-1-yl) acetic acid LCOOH (1) (L=(Pz)2CH–) and bis(3,5-dimethylpyrazol-1-yl)acetic acid L′COOH (2) (L=(3,5-Me2Pz)2CH–) with organotin oxide (hydroxide) precursors, n-BuSn(O)(OH), n-Bu2SnO, (n-Bu3Sn)2O and (Ph3Sn)2O has led to the isolation of several organotin compounds containing bispyrazolyl unit(s) on the periphery of the stannoxane structure [n-BuSn(O)O2CL]6 (3), [n-BuSn(O)O2CL′]6 (4), [n-Bu3SnO2CL] n (5), [n-Bu3SnO2CL′] n (6), [Ph3SnO2CL] n (7), [Ph3SnO2CL′] n (8), [{n-Bu2SnO2CL}2O]2 (9) and [{n-Bu2SnO2CL′}2O]2 (10). Compounds 5, 7, 9 and 10 have been structurally characterized by X-ray crystallography. In the solid state, these compounds possess interesting 3-D and 2-D supramolecular networks as a result of intermolecular C–H⋯O, C–H⋯N, C–H⋯Cl and C–H⋯π interactions. [Copyright &y& Elsevier]

Abstract: 1,4-Dioxane, a widely used industrial chemical and rodent hepatocarcinogen, has produced mixed, largely negative results in the mouse erythrocyte micronucleus assay. In contrast, a recent report has indicated that 1,4-dioxane induces micronuclei in mouse hepatocytes following in vivo treatment. The objective of this study was to confirm these earlier results and identify the origin of the induced micronuclei. Following an initial range-finding study, mice were administered 1,4-dioxane by gavage at doses ranging from 1500 to 3500mg/kg. The test animals were also implanted with BrdU-releasing osmotic pumps to allow cell proliferation to be measured in the liver and to increase the sensitivity of the hepatocyte assay. Upon sacrifice, the frequency of micronuclei in the bone marrow erythrocytes and in the proliferating BrdU-labeled hepatocytes was determined. Significant dose-related increases in micronuclei were seen in both the liver and the bone-marrow with significant increases being detected at all the tested doses in the bone marrow and at the 2500 and 3500mg/kg doses in the liver. Using CREST staining or pancentromeric FISH to determine the origin of the induced micronuclei, it was determined that 80–90% of the micronuclei in both tissues originated from chromosomal breakage. Small increases in centromere-containing micronuclei were also seen in the hepatocytes. Decreases in hepatocyte proliferation as well as in the ratio of bone marrow PCE:NCE were also observed. Based on these results, we conclude that at high doses: (i) dioxane exerts genotoxic effects in both the mouse bone marrow and liver; (ii) the induced micronuclei are formed primarily from chromosomal breakage; and (iii) dioxane can interfere with cell proliferation in both the liver and bone marrow. [Copyright &y& Elsevier]

The paper presents an in situ parameter estimation method to determine the equivalent circuit parameters of the three-winding transformer (TWT). The suggested method also estimates geometrically a complex parameter that is mutual leakage between secondary and tertiary windings, which would be useful in transient studies. Beside the saturation effect of the transformer is taken into account by estimating a highly nonlinear parameter that is magnetizing circuit reactance. Different search based optimization tools are applied for parameter estimation among which the results obtained using genetic algorithm is found to be encouraging. Load test data at one particular operating point namely supply voltage, load currents, input power, and load impedance is sufficient to estimate the parameters. The results are experimentally validated against the directly measured performance of TWT. The method is applicable for performance determination, power system load flow studies and design of protection circuits of the TWT. [Copyright &y& Elsevier]