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• The present work focuses on the amendment of the preparation of novel keto-enol mechanized chalcone material for optical and anti-biofilm application. • The material prepared application by simple one-step synthesis and deeply analyzed on the molecular optical property and the anti-bacterial property. • The chalcone materials shows AIE (Aggregation Induced Emission) property in nature. • The reals ample analysis of the materials obtained against the pig skin, and the material gives outstanding efficiency in antibacterial application. A solid-state photoluminescent 4-(Dimethylamino)-2ʹ-hydroxychalcone (Chalcone) compound was designed and synthesized using the Claisen–Schmidt condensation reaction. The optical and antibacterial of the prepared chalcone material were examined. The chemical structure of the synthesized material was confirmed by attenuated total reflectance–Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The prepared compound was grown as a single crystal in ethanol. The surface morphologies of chalcone material determined by field emission scanning electron microscopy revealed rectangular microcrystal formation in the solid. The thermal stability of the materials was studied using differential scanning calorimetry. A very sharp peak at 176.5 °C revealed its melting temperature to be in a higher range, suggesting that the crystal is highly stable towards temperature. The absorption and emission property of the material was determined by UV–visible and fluorescence spectrophotometry. The hardness test revealed the crystal to be strong and stable. The antibacterial and antibiofilm properties were evaluated against the Staphylococcus aureus (MSSA 6538) strain. The chalcone material was an ideal candidate for improving the antibiofilm and bactericidal agent against S. aureus. The results suggest that the material is suitable for optical and antibacterial applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Chronic Kidney Disease (CKD) and Cardiovascular Disease (CVD) have been inextricably linked since the earliest days of hemodialysis. Several statistics accrued since that time attests to the impact of cardiovascular disease in renal patients. Approximately one-half of all deaths in end-stage renal disease patients are attributable to cardiovascular disease, a proportion that is remarkably similar throughout the world. The aim of the study: To Evaluate latent systolic dysfunction and its relation with diastolic dysfunction in hemodialysis patients with normal ejection fraction, using Doppler-derived systolic time intervals. Materials and methods: This retrospective study was conducted in the Department of General Medicine, Government Mohan Kumaramangalam Medical College, Salem in 2017. Patients with systolicand diastolic blood pressures above 140 and 90 mmHg were grouped as hypertensive. According to this classification, 44% of patients were hypertensive. The control group comprised of healthy normotensive persons with no cardiovascular complaints, normal electrocardiogram (ECG) and normal blood chemistries. Results: In our study, 90% of patients with systolic dysfunction had normal IVRT and 84.4% of patients with diastolic dysfunction had normal STI index. However, as in the previous study, the impaired STI index, and prolonged IVRT are independent of the presence of hypertension or left ventricular hypertrophy and IVRT was more sensitive than E/A ratio to diagnose diastolic dysfunction. Conclusion: The most common features of uremic cardiomyopathy namely left ventricular hypertrophy, diastolic dysfunction and systolic dysfunction were present in 40%, 24%, and 40% of our hemodialysis patients respectively. The diastolic dysfunction and latent systolic dysfunction (STI>0.4) were randomly distributed. Impaired STI index and prolonged Isovolumetric relaxation time are independent of the presence of hypertension or left ventricular hypertrophy. [ABSTRACT FROM AUTHOR]

Graphical abstract Two new bis- and mono-tridentate chelated iron complexes, [FeII(LH) 2 ](ClO 4) 2 ·C 2 H 5 OH (1) and [FeIII(LH)Cl 3 ]·0.5CH 2 Cl 2 (2), with facially capping N-tridentate ligand, 2-(5,7-dihydro-6H-dibenzo[c,e]azepin-6-yl)-N-(pyridin-2-ylmethyl)ethan-1-amine, incorporating biphenyl-append (LH), have been synthesized and characterized by X-ray crystal structure, spectroscopic (FTIR, UV–Vis and ESI-MS) and magnetic susceptibility measurements. Crystal structures of 1 and 2 reveal pseudo-octahedral geometry with two ligand (LH) molecules arranged in trans-facial manner and similar geometry with one facially capping ligand, LH and three Cl−, respectively. Their characterizations in solution by spectroscopic (FTIR, UV–Vis and ESI-MS) methods and a qualitative variable temperature (20–300 K) magnetic susceptibility (VSM) of solids complement solid state structures. Abstract Two new bis- and mono-tridentate chelated iron complexes, [FeII(LH) 2 ](ClO 4) 2 ·C 2 H 5 OH (1) and [FeIII(LH)Cl 3 ]·0.5CH 2 Cl 2 (2) , with facially capping N-tridentate ligand, 2-(5,7-dihydro-6H-dibenzo[c,e]azepin-6-yl)-N-(pyridin-2-ylmethyl)ethan-1-amine, incorporating biphenyl-append (LH), have been synthesized and characterized by X-ray crystal structure, spectroscopic (FTIR, UV–Vis and ESI-MS) and magnetic susceptibility measurements. Structure of 1 reveals pseudo-octahedral geometry around Fe(II) with two ligands (LH) arranged in trans-facial manner, in two crystallographic independent molecules, Mol. A and Mol. B, differing in biphenyl twist angles, ϕ = 43.7° and 45.1°. Complex 2 has similar geometry with Fe(III) having one facially capping ligand, LH and three chlorides (Cl−), also in two crystallographic independent molecules, Mol. A and Mol. B, differing by biphenyl twist angles, ϕ = 40.9° and −42.7°. The UV–Vis absorption spectrum of 2 in CH 3 CN suggests competitive coordination between the two weakly-coordinating tertiary amine nitrogen atoms having biphenyl-append, and the solvent, CH 3 CN. The qualitative magnetic susceptibility measurements for 1 and 2 at 296 K provide moments of 4.2 μ B and 2.7 μ B , respectively, suggesting nearly high-spin, Fe(II) (S = 2) and a rare intermediate-spin, Fe(III) (S = 3/2). [ABSTRACT FROM AUTHOR]

The development of composite cements using supplementary cementitious materials is considered to be state of art in cement production. This paper presents the results of an experimental impact test conducted using drop weight hammer on fibre reinforced concrete (FRC) with 0.32 and 0.40 water/binder ratio made with binary and quaternary composite lime sludge cements. For this purpose, 34 concrete mixes containing hooked end steel fibres with aspect ratios of 50 at dosage of 0.5%, 1.0% and 1.5% were prepared with binary and quaternary cementitious systems. The binary systems were designed with various proportions of lime sludge ranging from 5%, 10% and 15%, while the quaternary systems were designed with various proportions of lime sludge combined with 15% of flyash and 10% of silica fume as partial substitute of cement. Further, a six regression models were constructed and validated for the assessment of effectiveness in determining the impact energy at first crack and failure. The results depict that replacement of 10% lime sludge in quaternary cementitious systems with this proportion is very effective in increasing the compressive strength and impact strength in concrete. [ABSTRACT FROM AUTHOR]

Treatment of the novel biphenyl-appended N,N′-bidentate ligand, 6-(2-pyridylmethyl)-6,7-dihydro-5H-dibenzo[ c , e ]azepine with FeX 2 (X = Cl - , Br − ) affords two stable four-coordinate, pseudo-tetrahedral [Fe(NN′)X 2 ] (where X = Cl − , 1 ; Br − , 2 ) complexes. In contrast, the same reaction in the presence of pseudo-halides, KNCS/Se, gives two six-coordinate distorted-octahedral, [ trans -Fe(NN′) 2 (NCE) 2 ] (where E = S, 3 ; Se, 4 ) complexes. All the four complexes were characterized by X-ray crystallography, spectroscopic (FTIR, Uv–Vis, paramagnetic 1 H NMR, Mossbauer of 1 ) methods, ESI-MS and variable-temperature magnetic susceptibility measurements (VSM, 20–300 K). The molecules in the crystal lattice are held together by several strong intermolecular hydrogen-bonding, π⋯π stacking (py-py or py-ph) and C–H⋯π (CH 2 -ph) interactions. The strong absorption spectral features of 3 and 4 in solution and the paramagnetic 1 H NMR spectra of 1 – 4 are interpreted. Variable-temperature magnetic susceptibility measurements of solids 1 – 4 show magnetic moment values near 4.9 B.M., characteristic of temperature-independent high-spin (S = 2) state for Fe(II). Mossbauer spectrum of 1 complements this property. The monomeric nature of 1 and 2 is an attractive feature, which may serve as invaluable precursor to model the active-site structure and function of mononuclear non-heme iron oxidase (MNO) enzymes, involved in O 2 activation and oxidation catalysis of aromatic organic substrates. [ABSTRACT FROM AUTHOR]

In the recent years, synthesis of nanomaterials using seaweeds and their diverse applications is escalating research in modern era. Among the noble metals, platinum nanoparticles (PtNPs) are of great importance owing to their catalytic property and less toxicity. The significance of this work is a simple one-step synthesis of PtNPs using aqueous extract of Indian brown seaweed Padina gymnospora and their catalytic activity with a polymer Polyvinylpyrrolidone (PVP) as PVP/PtNPs nanocomposite towards antimicrobial, haemolytic, cytotoxic ( Artemia salina) and antioxidant properties. Fourier Transform Infrared (FT-IR) spectrum results showed diversified functional groups (biomoeities such as carbohydrates and proteins) present in the seaweed extract is responsible for the reduction of platinum ions (Pt + ) to PtNPs. The seaweed mediated PtNPs was characterized by UV–vis spectrophotometer, X-ray diffraction (XRD) pattern, Field Emission Scanning Electron Microscopy (FESEM) equipped with Energy Dispersive X-ray (EDX) spectroscopy and High Resolution Transmission Electron Microscopy (HRTEM) analysis. The synthesized PtNPs was found to be truncated octahedral in shape with the range of 5–50 nm. Crystalline nature of the nanoparticles was evidenced by Selected Area Electron Diffraction (SAED) pattern with bright circular spots corresponding to (111), (200), (220) and (311) Bragg’s reflection planes. The size of the PtNPs was further evidenced by Dynamic Light Scattering (DLS) analysis and it is originate to be stable at −22.5 mV through Zeta Potential (ZP) analysis. The present study shows that the catalytic behavior of PtNPs as polymer/metal nanocomposite (PVP/PtNPs) preparation for an antibacterial activity against seven disease causing pathogenic bacterial strains with the maximum activity against Escherichia coli (15.6 mm) followed by Lactococcus lactis (14.8 mm) and Klebsiella pneumoniae (14.4 mm). But no haemolytic activity was seen at their effective bactericidal concentration, whereas increase in the haeomyltic activity was seen only in higher concentrations (600, 900 and 1200 μg mL −1 ). On the other hand, PVP/PtNPs nanocomposite has shown cytotoxic activity at 100 ± 4 μg mL −1 (LC 50 ) against Artemia salina nauplii. Furthermore, PVP/PtNPs nanocomposite showed an enhanced scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide, nitric oxide and hydroxyl radicals. [ABSTRACT FROM AUTHOR]

Novel bent-core materials containing a central core of 2, 5-disubstituted thiophene with chalcone as the side arm were synthesized and characterized to determine the structure–property relationship. The structural difference between two materials is the linking group in the thiophene and chalcone side arm. Chalcone is linked with thiophene by ester group in material I, while ester group is replaced with imine group in material II. The change in linking group exhibited a drastic difference in their physicochemical and intramolecular behaviors. Material I exhibits a hexagonal columnar mesophase at below room temperature, whereas material II exhibits a crystalline phase. Both liquid crystalline and crystalline properties were examined from polarized optical microscopy (POM), differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD) analyses. The highlight of this work is material I revealed a hexagonal columnar phase in the temperature ranges 22–38°C and undergoes photocrosslinking in UV light; contrarily, material II exhibits neither LC phase nor photocrosslinking property. [ABSTRACT FROM AUTHOR]

A simple eco-friendly approach for the hasty synthesis of stable, potent and benign silver nanoparticles (AgNPs) using seagrass, Syringodium isoetifolium was proposed and described here. The UV–Vis, DLS, XRD, AFM, FESEM, EDX and HRTEM analysis highly characterized and confirmed the presence of polydispersed (2–50 nm) spherical and stable AgNPs. FT-IR and phytochemical analysis suggested that the proteins act as reducing and also as capping agent. A hypothetical approach using bioinformatics tools revealed that the Phytochrome B protein of S. isoetifolium might be responsible for the biosynthesis of NPs. Furthermore, biosynthesized AgNPs showed magnificent antibacterial activity against thirteen clinical bacterial pathogens with maximum zone of inhibition of 14.3 ± 0.12 mm due to their smaller size and longer stability even at minimal nanomolar (nM) concentration. In addition, the MIC and MBC values also suggested the same. Moreover, the percentage of haemolysis (8.49 ± 3.10 to 73.34 ± 1.79%) and haemolytic index revealed the satisfactory biocompatibility of AgNPs that showed less/no haemolysis up to 3 nM concentration. Further, the toxicity effect of biosynthesized AgNPs against the brine shrimp, Artemia salina exhibited significantly increasing mortality (13 ± 4.7 to 100%) with LC 50 value at 4 nM concentration. Thus, the optical property, crystal structure, size, shape, stability, bactericidal activity, cytotoxicity, and biocompatibility apparently proved that the biologically synthesized AgNPs have typical properties of nanomaterials. [ABSTRACT FROM AUTHOR]

The present work focuses on the synthesis and characterization of poly(arylchalcone)’s (PCH I-IV) by reacting acetone with various dialdehydes for the first time at below ambient temperature followed by cyclization with phenylhydrazinehydrochloride to yield luminescent poly(arylpyrazoline)’s (PPY I-IV). The synthesized polymers were characterized by standard techniques such as, GPC, SEM, TGA, FT-IR, 1 H NMR, UV–Vis absorption and fluorescence spectroscopy, and electrochemical studies by cyclic voltammetry analyses. The Pyrazoline group hooked with different aryl donors such as benzene, thiophene, carbazole, triphenylamine, thus results a series of blue and green emitting materials. The obtained optical bandgap energy of the polymers (PPY I-IV) were 2.53, 3.41, 3.07, 3.10 eV respectively, suggest that all the polymers belongs to semiconducting category. The solvent effect of polymers was thoroughly studied and explained by Lippert-Mataga equation. The polymers I & IV display large degree of intra-molecular charge transfer in excited state evidenced from solvatochromic shift on the emission spectra. The obtained results demonstrate that they are promising materials for organic electronics applications. [ABSTRACT FROM AUTHOR]

Need: A systematic needs and planning assessment is considered critical prior to large scale program implementation of new interventions (Ekeland et al, 2010; Kidholm et al, 2012) to avoid costly implementation errors (AlDossary et al, 2017) A comprehensive tele-practice model of screening, identification and rehabilitation of children below 6 years with hearing and speech-language disorders is proposed in Tamil Nadu Towards this, a situational analysis was undertaken to understand the perceived needs and readiness for telepractice integration. Aim: To understand the existing needs and assess telepractice readiness among various public-sector stakeholders involved in identification and rehabilitation of children with disability using mixed methods approach Method: Cross-sectional design using mixed methods including Focus Group Discussion (FGD) and Semi-structured interviews (SSI) of various stakeholders and geospatial mapping. Study site: Two representative rural districts in South India, Tamil Nadu, having nearly equal population, area and socio-economic conditions were selected to conduct the study. Material: Purposive homogeneous sampling was used for FGDs and Maximum variation sampling was used for SSIs Fathers and mothers of children with disability under 6 years of age, and various service providers working in public-sector services participated in the study. Procedure: Guide development -- The Bowen's feasibility framework was used as the primary framework (Bowen D.J., et al., 2010) and relevant attributes from various telemedicine frameworks (Addotey- Delove M.N., et al., 2020; Kiberu, et al., 2019; AlDossary et al., 2017; Mauco, et al., 2018) were mapped to these constructs. The interview guides were developed based on this framework. Data collection: The FGDs were conducted inperson in the rural community, and the SSI was conducted in-person or through a secure video-conferencing platform depending on the participant's convenience The FGD and SSI were audio recorded with prior written consent of all participants. For the geospatial analysis, the address of all enumerated children with disability below 6 years of age and service providers (centre and staffing) were obtained for the study sites All public-sector service centres and providers were included Analysis: All recordings were verbatim transcribed and uploaded in NVIVO software v. 12. Each transcript was coded and themes were identified using a deductive approach. For geo-spatial analysis, the geo-locations of providers and patients were obtained using Google Maps platform with latitude and longitude information. Data was imported to a web-based GIS analysis software -- TNG is to obtain buffer maps, distances and spread maps. Results: FGDs were conducted on four groups of mothers, two groups of fathers, two groups of anganwadi teachers and two groups of primary and secondary government teachers SSIs were conducted with 3 ASLPs, 2 welfare officers and 5 special educators. Parental perceptions on availability and accessibility of diagnostic and rehabilitation facilities, barriers and challenges faced in seeking care, as well as satisfaction with quality of care were obtained Caregiver's comfort and agreeability for telepractice, their intention to try and perceived fit of telepractice was identified. The service providers perceived the currently available services for hearing and speech-language disorders to be inadequate and were ready to explore telepractice Yet, they perceived a need for training, capacity building and more community engagement before implementing such services. The visual map of geographic distribution of persons with disability and all service centres in the selected districts revealed regional disparities in availability of services, non-availability of ASLP staffing and the average distance travelled by patient to avail diagnostic and rehabilitation services in these districts. Conclusions: The situational analysis informed us about the key grass root level personnel who can be engaged for telepractice, parental and service provider apprehensions towards telepratice and suitable locations for integrating telepractice in the community. [ABSTRACT FROM AUTHOR]

Purpose: To report the prevalence of amblyopia risk factors in children with congenital nasolacrimal duct obstruction.Methods: A retrospective review of records of children with the diagnosis of congenital nasolacrimal duct obstruction (NLDO), who underwent probing from January 2009 to October 2011, was done. All of them underwent a complete ophthalmic evaluation including cycloplegic refraction and strabismus evaluation before probing.Results: A total of 142 children were included in this study. The mean age at presentation was 22.38 months (sample standard deviation (SSD) - 15.88). Amblyopia risk factors were defined according to two sets of guidelines: The American Association for Pediatric Ophthalmology and Strabismus (AAPOS) referral criteria guidelines and the new AAPOS Vision Screening Committee guidelines. Twenty-eight (20%) children were found to have some form of amblyopia risk factor based on the referral criteria prescribed by AAPOS. However, on applying modified guidelines described by Donahue et al., to analyze the same cohort, 21 children were found to have amblyogenic risk factors. Of these 28 children, 13 had significant astigmatism (>1.50 D), 8 children had hypermetropia (>3.50 D), and six children had anisometropia (>1.50 D). One child had significant cataract (media opacity >1 mm). None of the children in this series had either myopia or strabismus.Conclusion: Prevalence of amblyopia risk factor was found to be 20% in our study based on the older guidelines; however, it reduces to 14.78% by applying the modified guidelines. Despite this reduction, importance of a comprehensive ophthalmic examination including cycloplegic refraction in all children presenting with NLDO cannot be overstated. A close follow-up of these children is also essential to prevent the development of amblyopia. [ABSTRACT FROM AUTHOR]

Two pyrazoline core fluorescent materials were designed, synthesized and characterized by various approaches. The synthesized materials were confirmed by standard 1 H NMR and FT-IR techniques. Porous like morphologies were found from SEM analysis and the thermal stability of the materials analyzed with TGA–DSC analysis. Emission properties, quantum yield, lifetime and bandgap energy of the materials have also been studied. Solvent effect of absorption and emission spectral results indicated that the wavelength was red-shifted to increase the solvent polarity. The semiconducting nature was studied by UV–visible spectra, cyclic voltammetry analysis and theoretical calculation. I–V characteristic analysis was used to determine turn-on voltage of the materials for optoelectronics. [ABSTRACT FROM AUTHOR]

An investigation has been made to synthesize small organic materials possessing longer wavelength emission in a simple manner. Three novel pyrazoline compounds were synthesized and characterized by appropriate approaches. The effect of thiophene, furan and pyridine substitution on pyrazoline skeleton was studied and explained systematically. Green, blue and violet emission was obtained with respect to different substituent groups. The fluorescence decay time and quantum yield of the synthesized materials I , II and III are found to be 3.42, 2.65, 2.83 ns and 0.83, 0.76, 0.78 respectively. The theoretical quantum calculation was used to optimize the spatial distribution of ground state geometry (HOMO) and excited state geometry (LUMO) levels of the molecules. The materials performance and bandgap energies ( E g ) of all the three compounds revealed that they belong to a semiconductor materials category. [ABSTRACT FROM AUTHOR]

Two different novel heterocyclic compounds namely 2,5-bis(1,3-diphenyl-4,5-dihydro-1H-pyrazol-5-yl)thiophene (Material I ) and 2,5-bis(3-(naphthalen-1-yl)-1-phenyl-4,5-dihydro-1H-pyrazol-5-yl)thiophene (Material II ) were designed, synthesized and characterized by spectral methods. The synthesized materials were confirmed by standard techniques such as FT-IR, 1 H NMR and elemental analysis. Physical properties include thermal, surface morphology of the materials were explained from TGA, DSC and SEM analysis. Optical properties such as absorption, emission, solvent effect have been investigated by UV–Visible and fluorescence spectrophotometers. The blue and green emission of the materials was confirmed by using UV light as well as fluorescence spectrophotometers. Bandgap energies of these materials were obtained by both experimental and theoretical calculation from of cyclic voltammetry, UV–Visible spectrophotometer and DFT calculation. I–V characteristic analysis used to determine the threshold voltage ( V on ) of the two materials. The obtained results of the materials have promising to be applicable for opto-electronic applications. [ABSTRACT FROM AUTHOR]

Self-assembled molecular triangles [Pd(phen)(imidazolate)](NO), 1a and [Pd(phen) (imidazolate)](PF), 1b are prepared by the combination of imidazole with Pd(phen)(NO) and Pd(phen) (PF), respectively. Imidazole was deprotonated during the complexation reactions and the imidazolate so formed acted as a bis-monodentate bridging ligand to form the bowl-shaped trinuclear architectures of 1a/b. Relative orientation of the imidazolate moieties can be best described as syn,anti,antias observed in the crystal structure of 1b. However, in solution state, slow conformational changes are assumed on the basis of HNMR spectral data. The molecular triangles are crafted with three peripheral phen units capable of π− π stacking interactions. Well-fashioned intermolecular π− π interactions are observed in the solid-state, wherein further self-assembly of already self-assembled triangle is observed. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A rare variety of self-assembled molecular triangle [Pd(bpy)(imidazolate)](NO), 1 is prepared by the combination of Pd(bpy)(NO) with imidazole, at 1:1 ratio, in acetonitrile-water. Deprotonation of imidazole happened during the course of the complexation reaction where upon the metallomacrocycle is formed. The bowl-shaped trinuclear architecture of 1 is crafted with three peripheral bpy units capable of π− π stacking interactions. While the solution state structure of 1can be best described as a trinuclear complex, in the solid-state well-fashioned intermolecular π− π and CH- π interactions are observed. Thus, in the solid-state further self-assembly of already self-assembled molecular triangle is witnessed. The triangular panels are arranged in a linear manner utilizing intermolecular π− π interactions where upon two out of three bpy units of each molecule participated in the chain formation. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Introduction: The increase in mHealth based hearing applications provide improved access to hearing services in low- and middle-income countries (LMICs). Use of mobile/tablet based hearing screening in primary health care initiatives is likely to improve access to early identification of disabling hearing loss, especially among children in underserved regions. Objective: To beta- validate the prototype tablet-based subjective- behavioural hearing screening measures among children below six years for its accuracy in identifying children at risk for 40% or more hearing loss. Material and methods: Tablethearing screening device prototype was developed with hearing screening software coded using Python language. Suitable wireless headphones and speakers were finalised as transducers after checking calibration output. The screening tests incorporated behavioral observation and visual reinforcement audiometry and speech recognition threshold (SRT) screening. Stimuli for each test procedure were also developed as a part of this study. For beta validation of the prototype, 25 children were assessed for their thresholds using the standard audiometer and then through the prototype. Results: Agreement statistics was used to compare the screening results from the standard audiometer and the prototype for each frequency. Perfect agreement was obtained for all frequencies. Friedman test and descriptive analysis was used to compare the thresholds obtained using newly developed non tonal stimuli and the standard warble tone thresholds. On comparison, threshold obtained using non-tonal stimuli was appropriate and can be used as alternative stimuli for pediatric behavioral hearing screening. Results of speech recognition threshold screening revealed that presentation level of 5 dBSL of warble tone would be sufficient to obtain 50% recognition. Conclusions: The prototype was found to be satisfactory in identifying children who are at risk for 40% or more hearing loss. However, scope for improvement in device interface was also identified. [ABSTRACT FROM AUTHOR]

A highly selective and sensitive Al3+ and Cu2+ ion receptor (4-(dimethylamino)-2′-hydroxychalcone) was designed, synthesized, and characterized via standard techniques such as FT-IR and 1H NMR spectroscopy and GC-MS. The solvatochromism and keto–enol tautomerism of the material were studied in various solvents. The selectivity of the receptor was investigated using UV–visible and fluorescence spectrophotometry. The receptor was found to behave as a highly selective colorimetric turn-on sensor for the Al3+ ion by changing color from yellow to red with an association constant of 1.62 × 104 M−1 and a low detection limit of 1.02 × 10−7, and as a turn-off sensor for Cu2+ with an association constant of 4.98 × 104 M−1 and detection limit of 9.62 × 10−7. The present investigation confirms that the receptor acts as a selective fluorescence probe for the detection of Cu2+ ions. The highlight of this work is that the receptor is effective as a naked-eye sensor for Al3+ and Cu2+ ions. [Display omitted] • Simple organic receptor material prepared by Claisen-Schmidt Condensation reaction. • The Physico-chemical properties such as solvatochromism and metal ion sensing properties explained thoroughly. • Among the all metals, the receptor detects Cu2+ and Al3+ ions selectively. • The Cu2+ decolorizes and Al3+ induces the red color of the receptor that can observed by naked eye. [ABSTRACT FROM AUTHOR]

Photolysis of [{(μ3-BH)(Cp*Ru)Fe(CO)3}2(μ-CO)] (1; Cp* = η5-C5Me5) in the presence of various alkynessuch as 1,2-diphenylethyne, 1-phenyl-1-propyne, 2-butyne, and 1-(diphenylphosphino)-2-phenylacetyleneled to the formation of four types of novel heterometallic metallacarboranes,[1,1,1-(CO)3-μ-2,3-(CO)-2,3-(Cp*)2-4,6-Ph2-closo-1,2,3,4,6-FeRu2C2BH] (2), [1,8-(Cp*)2-2,2,7,7-(CO)4-μ-2,8-(CO)-μ-7,8-(CO)-4-Me-5-Ph-pileo-1,2,7,4,5-RuFe2C2(BH)2] (3), [1,8-(Cp*)2-2,2,7,7-(CO)4-μ-2,8-(CO)-μ-7,8-(CO)-4,5-Me2-pileo-1,2,7,4,5-RuFe2C2(BH)2] (4), and [1,2-(Cp*)2-6,6,7,7-(CO)4-μ-2,7-(CO)-exo-μ-5,6-(PPh2)-μ3-1,2,6-(BH)-4-Ph-pileo-1,2,6,7,4,5-Ru2Fe2C2BH] (5). Cluster compound 2exhibits an octahedralstructure with adjacent carbon atoms consistent with its skeletalelectron pair (sep) count of 7. The cage geometry of 3and 4is based on a pentagonal bipyramid with one additional{Cp*Ru} vertex capping one of its faces. The solid-state X-ray diffractionresults of 5suggest that the core geometry is a cappedpentagonal bipyramid, with an Fe–C bridging PPh2group. All the cluster compounds 2–5have been characterized by IR and 1H, 11B,and 13C NMR spectroscopy, and the geometries of the structureswere unequivocally established by crystallographic analysis. [ABSTRACT FROM AUTHOR]

Abstract: Chalcogen-stabilized dimolybdaboranes 3–5 (3: [(Cp∗Mo)2B4H5Se(Ph)], 4: [(Cp∗Mo)2B4H3Se2(SeCH2Ph)] and 5: [(Cp∗Mo)2B3H6(BSR)(μ-η1-SR)] (R=2,6-( t Bu)2-C6H2OH)) have been isolated from the mild pyrolysis of dichalcogenide ligands, RE-E‘R (R=Ph: E=S, E‘=Se; R=CH2Ph, [2,6-( t Bu)2-C6H2OH]: E=E‘=Se, S) and [(Cp∗Mo)2B4H8], 2, an intermediate generated from the reaction of [Cp∗MoCl4] (1) (Cp∗ =η5-C5Me5), with [LiBH4.thf]. The geometry of [(Cp∗Mo)2B4H5Se(Ph)] is similar to that of [(Cp∗Mo)2B5H9], in which one BH3 unit on the open face is replaced by a triple bridged selenium atom. All the compounds have been characterized in solution by 1H, 11B, 13C NMR and IR spectroscopy and elemental analysis. The structural types were unequivocally established by X-ray crystallographic analysis of compounds 3–5. [Copyright &y& Elsevier]

Abstract: A different approach developed for the preparation of palladium(II) based complexes [(Pd(bpy)) x (L) y ](NO3)2 x is modelled by using 4-phenylpyridine as ligand (L = 1). Various solvent systems are inspected to optimize the reaction condition for the preparation of the model complex [Pd(bpy)(4-phenylpyridine)2](NO3)2. The model complex is obtained quantitatively as a single product from a 1:1:2 mixture of Pd(NO3)2, 2,2′-bipyridine and 4-phenylpyridine when stirred at room temperature in CH3CN:H2O (1:1). The same reaction is performed in CD3CN:D2O (1:1) to monitor the progress of the reaction by recording 1H NMR. The kinetic products that formed initially got self-healed to give the desired product with in 6h. However, in DMSO-d 6 spontaneous arrangement leading to the targeted complex was observed and no kinetic product could be detected. When a similar reaction is performed with ethylenediamine instead of 2,2′-bipyridine a mixture of compounds are observed. Theoretical calculation throws some light on the principle behind the success of this method for the bpy based systems. The assembly, [Pd(bpy)(4-phenylpyridine)2](NO3)2 has been characterised by NMR, ESI-MS and single-crystal X-ray diffraction methods. [Copyright &y& Elsevier]

Abstract: e-Commerce is becoming an increasingly popular trend nowadays, where a consumer can buy a product through the internet. After buying a product, consumers can post their reviews and comments about the product in web sites and blogs. These comments can be a powerful source of finding out the consumer preferences and making recommendations of products to a new consumer who desires to buy a product. Even though there are existing systems which try to utilize these reviews and try to find the inherent quality of a product, a complete and comprehensive system is absent which provides a mechanism to rate products without any bias. Hence, an attempt is made to propose a complete system which starts from reviews collection to the analysis of reviews and the final score calculation of a product. The novel methods used in this system are the calculation of spam level of each review and the calculation of scores for each feature of a product. Fuzzy logic is used to calculate the spam level scores and the product ratings. [Copyright &y& Elsevier]

In the crystal structure of the title compound, C34H25NO3, the dihydropyrone ring is in a half-chair conformation and the five-membered heterocyclic ring is in an envelope conformation. [ABSTRACT FROM AUTHOR]

This paper reviews intriguing recent findings on the mechanisms of drug induced hearing loss caused by two major classes of therapeutic agents: the aminoglycoside antibiotics and cisplatin. Both drug categories are nephrotoxic as well as ototoxic. Aminoglycosides and cisplatin target the outer hair cells in the basal turn of the cochlea to cause high frequency sensorineural hearing loss in a substantial percentage of patients treated with these drugs. Each group of agents appears to generate reactive oxygen species within the cochlea that trigger downstream mechanisms leading to cell death. Various protective agents including antioxidants show promise in protecting the inner ear from damage in experimental animals. The only successful double-blind, placebo controlled clinical trial using a protective agent to prevent ototoxicity was carried out in China. Aspirin or placebo was given in combination with gentamicin. A significant decrease in hearing loss was observed. Successful clinical implementation of protective agents will require a cautious approach, so that the therapeutic effect of the anti-infective agent or anti-neoplastic drug is not attenuated. This may require novel methods of administration of protective agents, such as injection within the middle ear. This would provide a maximal dose of protective agent without systemic interference with the desired effect of the ototoxic agent.Kidney International (2007) 72, 931–935; doi:10.1038/sj.ki.5002434; published online 25 July 2007 [ABSTRACT FROM AUTHOR]

Two-stage fibre-reinforced concrete (TSFRC) is a novel fibrous concrete that differs from the conventional fibre-reinforced concrete (FRC) in several aspects including its placement technique, implementation, fabrication methodology, and high coarse aggregate content. Consequently, the available data from the open literature on the behaviour of the conventional FRC exposed to falling weight collision may not be applicable to TSFRC. For instance, the impact strength performance of the conventional FRC is well documented; however, for TSFRC this has not been duly examined. For the first time, this study pioneers the concept of impact strength of TSFRC under falling weight collision. For this purpose, short crimped fibres and long hooked end steel fibres at 1.5, 3.0, and 5.0% dosage were used in two-stage concrete (TSC). To this end, seven different mixes were prepared and tested under falling weight collision as per ACI committee 544. In addition, a statistical analysis has been performed to analyse the scattered test results by Weibull distribution. For determining Weibull parameters, 20 probability estimators have been used, and the best estimators are taken for the reliability analysis. Based on the obtained Weibull parameters, the impact strength of TSFRC has been reported in terms of reliability. The results revealed that the ability of using higher fibre dosages allows achieving greater impact resistance properties for novel manufacturing TSFRC. Indeed, the TSC with steel fibre dosages exceeding 5%, can be produced easily thus making this innovative, yet simple to produce concrete, a strong contender in many construction applications. The two-parameter Weibull theory has been found to be adequately suitable for analysing the variations in the number of impacts that induces first crack and failure of all group of TSFRC specimens. [ABSTRACT FROM AUTHOR]

Aims: Cangrelor has a potentially favorable pharmacodynamic profile in cardiogenic shock (CS). We aimed to evaluate the clinical course of CS patients undergoing percutaneous coronary intervention (PCI) treated with cangrelor.Methods and Results: We retrospectively identified 136 CS patients treated with cangrelor. Patients were 1:1 matched to CS patients from the IABP-SHOCK II trial not receiving cangrelor by age, sex, cardiac arrest, type of myocardial infarction, culprit lesion, glycoprotein IIb/IIIa inhibitor, and oral P2Y12-receptor inhibitor and followed-up for 12 months. The study cohort consisted of 88 matched pairs. Thirty-day and 12-month mortality was 29.5% and 34.1% in cangrelor-treated patients and 36.4% and 47.1% in control group (P = 0.34 and P = 0.08, respectively). The rate of definite acute stent thrombosis was 2.3% in both groups. Moderate and severe bleeding events occurred in 21.6% in the cangrelor and 19.3% in the control group (P = 0.71). Patients treated with cangrelor more frequently experienced ≥1 TIMI flow grade improvement during PCI (92.9% vs. 81.2%, P = 0.02).Conclusion: Cangrelor treatment was associated with similar bleeding risk and significantly better TIMI flow improvement compared with oral P2Y12 inhibitors in CS patients undergoing PCI. The use of cangrelor in CS offers a potentially safe and effective antiplatelet option and should be evaluated in randomized trials. [ABSTRACT FROM AUTHOR]

The solvation behavior of ionic liquids containing a common, 1,1,3,3-tetramethylguanidinium cation and different anions, phenylacetate and cinnamate, in water is examined through apparent molar properties. These ionic liquids were chosen because of their versatile applications as environment-friendly solvent, catalyst, and for dissolution and stability of biomolecules. In order to understand the ion-ion and ion-solvent interactions and effect of anion in dilute aqueous solutions of studied ionic liquids, the experimental measurements of density and speed of sound have been carried out as a function of molality (0.01 to 0.2 mol·kg − 1 ) and temperature from 293.15 to 318.15 K. Experimental data have been used to calculate the apparent molar and other derived thermodynamic properties. Further, Redlich-Meyer equation has been employed to obtain the apparent molar volume and isentropic compressibility at infinite dilution and the empirical parameters which are crucial in understating the hydrophilic and hydrophobic nature of studied ionic liquids. [ABSTRACT FROM AUTHOR]

A novel biomimetic f-HAp/PVP/Ag nanocomposite was synthesized under the ionic liquid medium, which was composed of inorganic and organic nanofillers like fluor-hydroxyapatite, silver nanoparticles and polyvinyl pyrrolidone. In composite synthesis, the first time we were used fluorine based ionic liquid for the fluorine contents on the fluor-hydroxyapatite nanoparticles which were resulting in very good crosslinking and interfacial bonding with the PVP and Ag nanoparticles. Ionic liquid has assisted good morphological structure of both inorganic materials. The chemical interaction and crystallinity changes of the nanocomposite were evaluated by FTIR and XRD studies. The surface morphology and composition of the samples were observed by FE-SEM, HR-TEM and EDS analyses. This report reveals that the greener approach for synthesis of fluor-hydroxyapatite nanocomposite and sustained delivery of silver and fluorine ions from the fluor-hydroxyapatite surface to the bacterial surface have been reducing the bacterial growth rate which was evaluated by different pathogenic bacterial strains via different methods and it also favourable cytotoxicity effect with human osteosarcoma (MG-63) cells. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, C31H25NO4, the five-membered heterocyclic ring is in an envelope conformation and the dihydropyrone ring is in a half-chair conformation. [ABSTRACT FROM AUTHOR]

From gem-difluoromethyl group of 1,1,2,2-tetrafluoroethyl ether and 2,2-difluoroalkylamide, proton can be removed by potassium bis(trimethylsilyl)amide in DMF, THF or toluene. The generated nucleophiles are then condensed with benzophenones, benzaldehydes or Schiff's bases to provide new fluorinated alcohols and amines. Some interesting solvent effects are also observed. [ABSTRACT FROM AUTHOR]

A one-pot procedure for the preparation of functionalized 1,4-dihydropyridines by three-component reaction using substituted heterocyclic aldehydes, ammonium acetate, and substituted β-ketoesters catalyzed by L-proline was described. Present protocol offers excellent yield up to 92%, flexibility with different substitution, convenient operation, and eco-friendliness. The synthesized products were confirmed by 1H-NMR, 13C-APT, and IR spectroscopy. Herein, final confirmation of the targeted motif was made by X-ray single-crystal analysis of representative compounds (4f, 4j, 4k, 4l, and 4o). The chemically synthesized compounds were evaluated for the antiproliferative activity by cell viability (MTT) assay and dual AO/EB (acridine orange/ethidium bromide)-staining method against human A549 lung cancer cell lines. The viability of the treated cell was evaluated adopting MTT assay. According to associated changes in cell membranes during the process of apoptosis, a clear difference was observed between normal cells, early and late apoptotic cells, and necrotic cells. All compounds were found effective against Saccharomyces cerevisiae which was confirmed by increased reactive oxygen species production and DNA damage as compared to untreated yeast cell culture. Altogether, these compounds showed promising hope for application in pharmaceutical aid against yeast infections. [ABSTRACT FROM AUTHOR]

Thermolysis of an in situ generated intermediate, produced from the reaction of [Cp*MoCl4] (Cp* = η5-C5Me5) and [LiBH4.THF], with excess Te powder yielded isomeric [(Cp*Mo)2B4TeH5Cl] (2 and 3), [(Cp*Mo)2B4(μ3-OEt)TeH3Cl] (4), and [(Cp*Mo)4B4H4(μ4-BH)3] (5). Cluster 4 is a notable example of a dimolybdaoxatelluraborane cluster where both oxygen and tellurium are contiguously bound to molybdenum and boron. Cluster 5 represents an unprecedented metal-rich metallaborane cluster with a cubane core. The dimolybdaheteroborane 2 was found to be very reactive toward metal carbonyl compounds, and as a result, mild pyrolysis of 2 with [Fe2(CO)9] yielded distorted cubane cluster [(Cp*Mo)2(BH)4(μ3-Te){Fe(CO)3}] (6) and with [Co2(CO)8] produced the bicapped pentagonal bipyramid [(Cp*MoCo)2B3H2(μ3-Te)(μ-CO){Co3(CO)6}] (7) and pentacapped trigonal prism [(Cp*MoCo)2B3H2(μ3-Te)(μ-CO)4{Co6(CO)8}] (8). The geometry of 8 is an example of a heterometallic boride cluster in which five Co and one Mo atom define a trigonal prismatic framework. The resultant trigonal prism core is in turn capped by two boron, one Te, and one Co atom. In the pentacapped trigonal prism unit of 8, one of the boron atoms is completely encapsulated and bonded to one molybdenum, one boron, and five cobalt atoms. All the new compounds have been characterized in solution by IR, 1H, 11B, and 13C NMR spectroscopy, and the structural types were unambiguously established by crystallographic analysis of 2 and 4-8. [ABSTRACT FROM AUTHOR]

Reaction of tetraethoxysilane (TEOS) with substituted catechols (I-X), 7,8-dihydroxyflavone (XI), 3,3′,4′-trihydroxyflavone (XII), 3′,4′,5,7-tetrahydroxyflavone (XIII), and 9-phenyl-2,3,7-trihydroxy-6-fluorone (XIV) in the presence of an amine (molar ratio 1:3:2) in acetonitrile affords the corresponding dianionic hexacoordinate silicon(IV) complexes 1-15 having a “SiO6” structural fragment. The dianionic silicates were isolated as di-n-propylammonium/triethylammonium/di-n-butylammonium salts and were characterized by elemental analysis and various spectroscopic data (IR, 1H, 13C, and 29Si NMR). The solid state structures of compounds [(n-C3H7)2NH2]2[{Cl4C6O2}3Si] (1) and [(n-C3H7)2NH2]2[{Br4C6O2}3Si] (2) were determined by single crystal X-ray diffraction. Both 1 and 2 crystallize in the monoclinic space group C2/c and reveal (i) bidentate mode of ligation, (ii) octahedral coordination around silicon, and (iii) hydrogen bonding features. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. GRAPHICAL ABSTRACT [ABSTRACT FROM AUTHOR]

Vanadaborane, [(CpV)2(B2H6)2] (Cp = η5-C5H5), 1 reacts with elemental sulfur to afford the hexasulfide cluster [(CpV)2S4(μ-η1-S2)], 2 in high yield. Compound 2 is a notable example of an organovanadium sulfide cluster in which the [V2S4] atoms define a bicapped tetrahedron framework, with one μ-η1-S2 ligand bridged the two (CpV) moieties. The sulfur atom in [V2S4] core in 2 is a four-skeletal-electron donor isoelectronic with the BH3 unit; therefore, the replacement of boron hydride in 1 by four sulfur atoms necessitates the formation of a bicapped tetrahedron [V2S4] framework. Furthermore, this is the only reported example of a bimetallic hexasulfide cluster containing vanadium. Pyrolysis of 1 with bis-chalcogenide ligands such as Ph2S2 and Bz2Se2 (Bz = PhCH2), results in the formation of substituted vanadahexaboranes [(CpV)2B4H12-xLx], 3-5 (3: L = SPh: x = 3; 4: L = SPh, x = 2; 5: L = SeBz: x = 1) in modest yield. All these new compounds have been characterized by mass, 1H, 11B, 13C NMR spectroscopy, and elemental analysis, and the structural types were unequivocally established by crystallographic analysis of compounds 2-5. [ABSTRACT FROM AUTHOR]

Abstract: Reaction of (η5-C5Me5)MoCl4 with 6-fold excess of LiBH4·thf followed by pyrolysis with BHCl2·SMe2 in toluene at 90°C yielded known (η5-C5Me5Mo)2B5H9 (1) and B-Cl inserted (η5-C5Me5Mo)2B5H8Cl (2), (η5-C5Me5Mo)2B5H7Cl2 (3–5, three isomers) and (η5-C5Me5Mo)2B5H5Cl4 (6). In addition, reaction of (η5-C5Me5Mo)2B5H9 with 5-fold excess of n-BuLi followed by excess of MeI in THF yielded B-Me inserted metallaboranes (η5-C5Me5Mo)2B5H7(CH3)2 (7, 8 two isomers) and (η5-C5Me5Mo)2B5H6(CH3)3 (9, 10 two isomers). Isolated yields of 2–6 are poor but 7–10 are modest to good. Compounds 2–10 can be viewed as bicapped closo trigonal bipyramidal geometry. All the new compounds have been characterized in solution by IR, 1H, 11B, 13C NMR and mass spectroscopy as simple substitution derivatives of (η5-C5Me5Mo)2B5H9 and the structural types were unequivocally established by crystallographic analysis of compounds 2, 3, 5 and 6. [Copyright &y& Elsevier]

Present study focuses on the development of sustainable green-sourced carbon nano-sphere (CNSp) from Betel Leaf by thermal decomposition method for high-performance Polyurethane coating. The obtained carbon black was then functionalized with acid solution. FTIR analysis confirms the presence of carboxyl group. The graphitic domain present in the nano-sphere were found using XRD and Raman spectroscopy. TEM analysis clearly shows the mono-dispersed sized nano-spheres of about ~ 40 nm. The nano-sphere was further incorporated into castor oil based Polyurethane coatings. The nanoscale incorporation of the CNSp (0.2 and 0.5%) into the PU shows good increment in the resultant mechanical and thermo-mechanical properties of the polyurethane/carbon nano-sphere hybrid in comparison to the virgin PU film. The DMTA result shows an increase in the storage modulus from 3730 to 4454 MPa. Moreover, an accretion in the tensile strength was observed from 5.55 to 9.77 MPa Overall increments of 76.03% and good surface roughness observed by SEM analysis. [ABSTRACT FROM AUTHOR]

The influence of lattice strain on metal and metal oxide catalysts has been widely investigated by DFT calculations. However, it is still hard to prove by experimental methods. In the present investigation, we have explained how the experimentally obtained strain values are reflected in the catalytic decomposition of hydrogen peroxide by using MnO2 decorated on TiO2 and ZnO catalysts. The lattice strain parameter values have been derived from X-ray diffraction patterns using the modified Williamson–Hall (W–H) method. Uniquely, we observed that compressive strain could significantly affect the TOF of the reaction, especially on the MnO2/TiO2 catalyst. Furthermore, the equilibrium constant calculated from the Langmuir–Hinshelwood (L–H) kinetic model shows that the MnO2/TiO2 catalyst has a stronger adsorption capacity than the MnO2/ZnO material. These results directly reflect the strength of the oxophilic sites and the lattice strain of the materials. A quantitative relationship has been established between lattice strain and catalytic activity. [ABSTRACT FROM AUTHOR]

Abstract: New multinuclear discrete heteroleptic complexes have been synthesized by mixing Pd(II), 2,2′-bipyridine and N,N′-(1,2-phenylene)diisonicotinamide in a single pot as a new approach. A dimeric molecular rhombus and a trimer in equilibrium are obtained where the dimer is the major product. Similar equilibrium is also observed when classical method is employed for the synthesis. The equilibrium is shifted exclusively in favour of the dimer upon addition of benzene. The complexes are characterized by NMR and ESI-MS methods. Crystal structure of the benzene encapsulated rhombus is presented. [Copyright &y& Elsevier]

Polybenzoxazine (PBz)/BMI/reduced graphene oxide (rGO) nanocomposites were prepared by varying the weight percentage of rGO from 1 to 5 wt%. The exfoliated sheet morphology of rGO makes it well-dispersed in the PBz/BMI matrix. The curing process monitored by DSC analysis showed two exothermic curves. Of which one is due to the reaction between BMI and furan ring and the other due to ring-opening polymerization. The nanocomposites did not show any agglomeration even at higher loadings (5 wt%) of rGO nanofillers. The degree of dispersion of rGO nanofillers resulted in enhancement of mechanical and thermal properties of PBz/BMI/rGO nanocomposites. A very low percentage of the nanofillers of about 5 wt% could tremendously increase the thermal stability, storage modulus and dielectric properties of the nanocomposites. [ABSTRACT FROM AUTHOR]

Abstract In the present work we have investigated the fluorescence and nonlinear optical property of a new naphthalene family crystal, Decyl 6-(decyloxy)naphthalene-2-carboxylate (D6DN2C). This crystal was grown for the first time by slow evaporation solution technique (SEST). Single crystal X-ray diffraction analysis reveals that D6DN2C belongs to triclinic crystal system with centrosymmetric space group of Pī. The determined lattice parameters are a = 8.669 (3) Å, b = 9.495 (3) Å, c = 19.757 (6) Å, α = 82.697 (1)°, β = 77.726 (1)°, γ = 65.465 (1)°and volume = 1444.17 (8)Å3. Functional groups present in D6DN2C were identified by FT-IR studies. Transparency of the title crystal in UV–Visible region was analyzed and the optical band gap energy was found to be 3.51eV.Fluorescence spectra were recorded for the excitation wavelength of 300 nm. The negative third order nonlinear optical parameters like refractive index (n 2), absorption coefficient (β) and susceptibility (χ(3)) were estimated by Z-scan studies. Graphical abstract Image 1 Highlights • A good quality organic crystal Decyl 6-(decyloxy)naphthalene-2-carboxylate in triclinic system was grown. • The optical band gap was found to be 3.51 eV. • Exhibits violet fluorescent emission. • Third order nonlinear parameters were estimated by Z-scan studies. [ABSTRACT FROM AUTHOR]

Polytriazoleimide/reduced graphene oxide (PTAI/RGO) nanocomposites were prepared by typical solution casting and thermal imidization method. Initially, the GO was synthesized by Hummers method, then reduced with hydrazine hydrate to obtain RGO and the diamine containing 1,2,3‐triazole ring and alkyl chain were synthesized by the 1,3‐dipolar cycloaddition reaction in the presence of Cu(I) catalyst by click reaction. The monomers and polymers were characterized by FTIR and NMR spectroscopy. The mechanical, thermal, and morphological properties of PTAI/RGO (0, 1, 2 and 3 wt%) are reported. The glass transition temperature of the nanocomposites is in the range of 164–182°C. The tensile strength of the PTAI/RGO nanocomposites film was dramatically increased from 72 to 114 MPa from 0 to 3 wt% of RGO, which is ∼53% of improvement compared to that of pure PTAI films and the corresponding tensile modulus increased from 1.4 to 2.65 GPa. The thermogravimetric analysis (TGA) of the nanocomposites improved the thermal stability by the addition of RGO. The temperature corresponding 5% (T5%) weight loss are in the range of 280–331°C. The dispersion of RGO in the surface of the nanocomposites was analyzed by scanning electron microscopy and transmission electron microscopy. This effective approach shows a potential application in polyimides‐based nanocomposites. POLYM. COMPOS., 39:4425–4433, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Background: While open access publishing among cardiovascular journals has increased in scope over the last decade, the relationship between open access and article citation volume remains unclear.Methods: We evaluated the association between open access publishing and citation number in 2017 among 4 major cardiovascular journals. Articles indexed to PubMed with ≥5 citations were identified among the following journals: Circulation, European Heart Journal, Journal of the American College of Cardiology, and JAMA Cardiology. Multivariable Poisson regression models were adjusted for journal and article type.Results: Of the 916 articles published in 2017, original investigations accounted for most articles (66.7%), followed by reviews (14.5%), guideline/scientific statements (8.4%), research letters (3.7%), viewpoints (3.7%), and editorials (2.9%). Among all articles, 43% (n = 391) were open access. Citation number was higher among open access articles compared with those with subscription access (14 [25th-75th percentile: 9-23] vs 11 [25th-75th percentile: 7-17]; P < .001). Open access status was significantly associated with higher number of citations after multivariable adjustment (β coefficient: +0.42; 95% confidence interval, 0.38-0.45, P < .001). Open access articles had consistently higher citations compared with subscription access articles across the 3 most frequent article types.Conclusion: Among contemporary articles published in major cardiovascular journals, open access publishing accounted for over 40% of articles and was significantly associated with increased short-term citations. Further research is required to assess the variation in long-term citation rates based on open access publishing status. [ABSTRACT FROM AUTHOR]

Trinuclear complexes of group 6, 8, and 9 transition metals with a (μ3-BH) ligand [(μ3-BH)(Cp*Rh)2(μ-CO)M′(CO)5], 3 and 4 ( 3: M′=Mo; 4: M′=W) and 5- 8, [(Cp*Ru)3(μ3-CO)2(μ3-BH)(μ3-E)(μ-H){M′(CO)3}] ( 5: M′=Cr, E=CO; 6: M′=Mo, E=CO; 7: M′=Mo, E=BH; 8: M′=W, E=CO), have been synthesized from the reaction between nido-[(Cp*M)2B3H7] ( nido- 1: M=Rh; nido- 2: M=RuH, Cp*=η5-C5Me5) and [M′(CO)5 ⋅thf] (M′=Mo and W). Compounds 3 and 4 are isoelectronic and isostructural with [(μ3-BH)(Cp*Co)2(μ-CO)M′(CO)5], (M′=Cr, Mo and W) and [(μ3-BH)(Cp*Co)2(μ-CO)(μ-H)2M′′H(CO)3], (M′′=Mn and Re). All compounds are composed of a bridging borylene ligand (B−H) that is effectively stabilized by a trinuclear framework. In contrast, the reaction of nido- 1 with [Cr(CO)5 ⋅thf] gave [(Cp*Rh)2Cr(CO)3(μ-CO)(μ3-BH)(B2H4)] ( 9). The geometry of 9 can be viewed as a condensed polyhedron composed of [Rh2Cr(μ3-BH)] and [Rh2CrB2], a tetrahedral and a square pyramidal geometry, respectively. The bonding of 9 can be considered by using the polyhedral fusion formalism of Mingos. All compounds have been characterized by using different spectroscopic studies and the molecular structures were determined by using single-crystal X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]