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Chemical-based carotenoids have large implications to health as they may cause adverse side effects. Naturally occurring carotenoids mainly from microalgal sources are emerging as excellent substitute to combat cancer diseases. Astaxanthin is the most powerful antioxidant that derived from selected established microalgae with limited yield. Microalgal bioprospecting may provide the high-yielding sources for astaxanthin production. Hence, in the present research, freshwater microalgae Monoraphidium sp. (NCM no. 5585) and Scenedesmus obliquus (NCM no. 5586) were chosen to explore the unique potential of producing astaxanthin. Identification of bioactive metabolites in extracted carotenoid was analyzed through HPLC. Astaxanthin is identified as a major bioactive metabolite in both carotenoid fraction and β carotene only in Scenedesmus obliquus. Antioxidant potential of microalgal carotenoids was obtained by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric-reducing antioxidant power (FRAP) assay. The anti-proliferation activity of the extracted carotenoid from Monoraphidium sp. and Scenedesmus obliquus was evaluated against hepatocellular liver carcinoma cell line HUH7 by 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) colorimetric assay. Higher astaxanthin in Monoraphidium sp. leads to boosted antioxidant and anti-proliferation activity contrary to Scenedesmus obliquus that possess both astaxanthin and β carotene. Though freshwater microalgae have a huge potential to create beneficial metabolites like carotenoids, they are rarely studied in the pharmaceutical industry. This work was the first to investigate the anti-proliferative activity of Monoraphidium sp. and Scenedesmus obliquus carotenoid fraction on the HUH7 hepatocarcinoma cell line. [ABSTRACT FROM AUTHOR]

In recent decades, due to abundance (second most abundant natural polymer after cellulose) and sustainability, lignin has attracted much interest from different researchers to use as a raw material for producing various value-added materials such as polymer and fuel. In addition to that, the aromatic structure of lignin makes it a suitable candidate for producing platform chemicals with aromatic rings. As a result, lignin depolymerization has become an interesting process to derive different phenolic monomers like vanillin, acetosyringone, and guaiacol. Among them, due to the bioactive characteristics and efficiency of acetosyringone in plant regulatory systems, the production of acetosyringone from lignin has been presented in this work. A green and cost-effective method was developed for the selective formation of acetosyringone via depolymerization of isolated rice straw lignin (RSL) by using metal catalyst-free conditions in the biphasic medium and described. The RSL was characterized with various spectroscopic techniques such as FT-IR, solid-state 13C NMR, XPS, and TGA. The selectivity of synthesized acetosyringone during depolymerization of RSL was checked from GC-MS analysis. The molecular structure and purity of acetosyringone isolated from preparative thin layer chromatography (TLC) were confirmed with the help of 1H NMR and HRMS, respectively. [ABSTRACT FROM AUTHOR]

The pace of water contamination is increasing daily due to expanding industrialisation. Finding a feasible solution for effectively remediating various organic and inorganic pollutants from large water bodies remains challenging. However, a nano-engineered advanced hybrid material could provide a practical solution for the efficient removal of such pollutants. This work has reported the development of a highly efficient and reusable absorbent comprising a porous polyurethane (PU) and reduced graphene oxide (rGO) nanosheets (rGOPU) for the removal of different organic oils (industrial oil, engine oil and mustard oil), dyes (MB, MO, RB, EY and MV) and heavy metals (Pb(II), Cr(VI), Cd(II), Co(II) and As(V)). The structure, morphology and properties of the rGOPU hybrid absorbents were analysed by using Raman spectroscopy, field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and Brunner-Emitte-Teller (BET) analysis. The rGOPU possessed both superhydrophobicity and superoleophilicity with water and oil contact angles of about 164° and 0°, respectively. The prepared rGOPU has demonstrated an excellent oil-water separation ability (up to 99%), heavy metals removal efficiency (more than 75%), toxic dye adsorption (more than 55%), excellent recyclability (> 500 times for oils), extraordinary mechanical stability (90% compressible for > 1000 cycles) and high recoverability. This work presents the first demonstration of rGOPU's multifunctional absorbent capacity in large-scale wastewater treatment for effectively removing a wide variety of organic and inorganic contaminants. [ABSTRACT FROM AUTHOR]

Polyaniline-graphite (PANI-Graphite) composite deposited on cellulose paper substrate has been studied for the development of a glucose biosensor kit. Thin graphite layers were deposited by pencil graphite on one side of the commercially available cellulose paper substrate, and upon that the layer of PANI was deposited through a physical vapor deposition technique. The physical characterizations of the prepared samples were carried out using X-ray diffraction analysis, ultraviolet (UV)-visible absorption spectroscopy, scanning electron microscopy, and electrical transport measurements. The sensing responses of glucose with different concentrations were studied by observing the resistive changes due to glucose interaction. The analysis of sensor studies shows a nearly linear response with a sensitivity of 18.78 μA(mg/dL)−1 cm−2 for the variation of glucose concentration. The limit of detection has been obtained as 1.6 mg/dL. The results indicate that PANI-Graphite on cellulose would be a potential candidate for using it as an active material for glucose concentration detection and it would find a profound interest because of its very lightweight, low cost, the flexibility of a paper-based kit, and is a biodegradable one. [ABSTRACT FROM AUTHOR]

A simple, rapid, and sensitive electrochemical biosensor based on a screen-printed carbon electrode (SPCE) was developed for onsite detection of E. coli in real time. This work analyzed the effect of aptamer conjugation and PBS buffer solution on the colloidal stability of the silver nanoparticles (AgNPs). Aggregations of the AgNPs after aptamer conjugation in PBS buffer were observed from the particle size distribution analysis. The AgNP-aptamer conjugation and its affinity towards E. coli (DH5α) were confirmed by UV–visible spectrophotometry, which showed a linear increment in the absorption with increasing E.coli concentration. The screen-printed carbon electrodes were modified by drop-casting of AgNPs, which were used as an effective immobilization platform for E. coli-specific aptamers. The modified electrode's surface modification and redox behavior were characterized using cyclic voltammetry. Finally, E. coli was detected using differential pulse voltammetry with an optimized incubation time of 15 min. The developed biosensors showed a linear decrease in current intensity with an increase in the concentration of E. coli. The biosensor had a relative standard deviation (RSD) of 6.91% (n = 3), which showed good reproducibility. The developed biosensors are highly sensitive and have a limit of detection (LOD) as low as 150 CFU/ml. The biosensor showed good selectivity for E.coli coli when comparing the signal response obtained for bacteria other than E.coli. Also, the biosensor was found stable for four weeks at room temperature and showed high recoveries from 95.27% to 107% during the tap water sensitivity validation. [ABSTRACT FROM AUTHOR]

Ugi-four component reaction (Ugi-4CR) is extremely attractive for diversity-oriented and step economical synthesis as evident from past applications. Here we report the synthesis of fused polycyclic β-carboline derivatives by sequential Pictet-Spengler's and Ugi-4CR multi-component reaction followed by cascade cyclization. The post cyclisation of Ugi product provides conformationally stable heterocyclic molecule that is expected to be suitable for interaction with different biological targets. The methodology provides a simple and facile access to heterocycles embedded in polycyclic framework which otherwise seems difficult to synthesize by conventional methods. Synthesis of fused Polycyclic β-Carboline Derivatives Using Ugi-4CR Followed by Cascade Cyclization [ABSTRACT FROM AUTHOR]

This study proposed a two-step method involving hydrothermal and electrostatic self-assembly processes for synthesising an amine-functionalised magnetic ligand graphene oxide–based nanocomposite (EDTA@Fe3O4@GO). The amine groups were successfully attached to the surface of iron (II, III) oxide (Fe3O4), which were embedded on the surface of graphene oxide (GO) (Fe3O4@GO). This EDTA@ Fe3O4@GO nanocomposite was used as a chelating agent to bind the toxic heavy metal ions. EDTA@Fe3O4@GO demonstrated the synergistic effect between the large surface area and magnetic behaviour of Fe3O4@GO and the chelating effect of EDTA, and it showed higher efficiency than the individual GO and Fe3O4. The possible structural and compositional characteristics were proposed based on Fourier transform infrared spectra (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer–Emmett–Teller (BET) and Raman spectroscopy analysis. The outcomes revealed the mechanism behind the excellent As(V) adsorption onto EDTA@Fe3O4@GO. The adsorption process was studied by fitting the experimental data obtained into various kinetic and isotherm models. The pseudo-second-order (PSO) kinetic model and the Freundlich isotherm model (FIM) were found to be the best fit models for the removal of As(V) by EDTA@Fe3O4@GO. EDTA@Fe3O4@GO has the utmost adsorption capacity of 178.4 mg/g. Furthermore, the EDTA@Fe3O4@GO nanocomposite is reusable, and it showed excellent adsorption capacity up to 5 cycles. This study has provided insight into the potential of EDTA@Fe3O4@GO and its applications in large-scale wastewater treatment. [ABSTRACT FROM AUTHOR]

A Composite of PANI with CuBO2 has been prepared by a solid-state synthesis method and its thermoelectric performance has been studied. The PANI/CuBO2 composite mixture shows p-type conduction with exceptionally improved Seebeck coefficient (S) and electrical conductivity (σ) as well as thermoelectric power factor (P = S2σ). The outstanding enhancement in TE properties of the composite mixture is attributed to the reduction of π-π conjugated defects in the polymer chain matrix. The highest values of electrical conductivity and Seebeck coefficient for the prepared composite mixture reach 0.34 S/cm and 0.43 mV/°C, respectively, and the maximum TE power factor as recorded is 6.28 μW/mK2, which is about 107-fold larger in magnitude than that of pure PANI. The power factor as achieved at a comparatively lower temperature difference below 100 °C indicates that these powder mixtures of PANI/CuBO2 can be an effective material for better performance in thermoelectric energy harvesting from waste heat. [ABSTRACT FROM AUTHOR]

This era of industrial upgradation has wreaked havoc on the aquatic environment as well as human health by accumulating various toxic water pollutants such as synthetic dyes and heavy metals. Thus, in this study, in order to explore the effectiveness of adsorptive sequestration processes of metanil yellow (MY) dye and Cr (VI) ions from aqueous media, CaFe2O4/ZrO2 magnetic nanocomposite (CaFe2O4/ZrO2-MNC) was prepared. The improvement in adsorption capacity was significantly evident as CaFe2O4/ZrO2-MNC had shown much higher adsorption capacities for both MY dye and Cr (VI) than both parent metal oxide nanoparticles (CaFe2O4 and ZrO2). The treatment cost analysis depicted that the laboratory scale fabrication cost (INR 2635/kg) of CaFe2O4/ZrO2-MNC can be significantly reduced during industrial scale fabrication process of CaFe2O4/ZrO2-MNC (INR 573/kg). As a consequence, the reduction in overall treatment cost of per kg MY dye as well as per kg Cr (VI) was found to be quite significant and is expected to be reduced more as regeneration study performed in case of MY dye had highlighted that CaFe2O4/ZrO2-MNC can be successfully used for even five adsorption–desorption cycles. Finally, the scale up design performed in this study also indicates towards the possibility of scalability of both treatment processes as only 22.26 g and 50.46 g of CaFe2O4/ZrO2-MNC may be used to remove 95% of MY dye and Cr (VI), respectively. Hence, this study confirms the potential economical application of CaFe2O4/ZrO2-MNC in both dye and heavy metal adsorption processes since the adsorbent poses satisfactory structural stability and reusability.Article Highlights: This study reported the fabrication of novel CaFe2O4/ZrO2 magnetic nanocomposite. Enhancement of adsorptive performance of mixed phase nanocomposite due to the coexistence of CaFe2O4 and ZrO2 nanoparticles. The composite has shown maximum adsorption capacity of 454.55 mg/g for MY dye and 178.57 mg/g for Cr (VI). The cost analysis study has revealed laboratory scale and industrial scale monetary investments of INR 2635 and INR 573, respectively for the fabrication of 1.0 kg of CaFe2O4/ZrO2-MNC. The industrial scale treatment cost analysis has shown significant reduction in cost involved in 1.0 kg of MY dye and Cr (VI) abatement from aqua matrix with a monetary requirement of INR 1262 and INR 3212, respectively. The scalability of MY and Cr (VI) adsorption processes may be proposed as only 22.26 g and 50.46 g of CaFe2O4/ZrO2-MNC are required to remove 95% of MY dye and Cr (VI), respectively from aqua media. [ABSTRACT FROM AUTHOR]

Adsorption mechanism and inhibitive performances of alkaloids on mild steel are studied using density functional theory (DFT). Global reactivity parameters such as global hardness (ɳ), fraction of electron transfer from molecule to metal (∆N), and dipole moment (μ) are calculated to determine corrosion protection efficiency. Periodic DFT calculations show bonding interactions between heteroatoms of alkaloid and Fe atom of Fe(110) surface. Fe–-H non-classical bond formations are also observed. The order of adsorption energy (Eads) is quinine (86.6 kcal/mol) > cytisine (67.6 kcal/mol) ≈ mescaline > ephedrine > morphine ≈ atropine > nicotine > caffeine > tryptamine > codeine (50.2 kcal/mol). Highest Eads value of quinine is interpreted with its very favourable orbital energies that help to form chemical bonds via electron donation and back donation. These high Eads values confirmed chemisorption process and interpreted strong inhibition efficiencies of morphine and caffeine on mild steel as reported in experimental studies. [ABSTRACT FROM AUTHOR]

Purpose: Endocomia macrocoma subsp. prainii W.J. de Wilde is distributed in subtropical mixed evergreen forest as tall tree and bears single seeded fruits as nontimber forest products and biowaste. The study aimed at physicochemical characterization and comparison of crude seed kernel wax of Endocomia macrocoma subsp. prainii (EW) collected from Assam and Tripura with bee wax (BW) for valorization potential. Methods: Endocomia macrocoma kernel was extracted in Petroleum ether to yield crude wax (EW). Morphological and physicochemical characterization of EW and BW was carried out by Scanning Electron Microscopy (SEM), Thermogravimetric analysis, UV–Visible spectroscopy, FTIR, XRD and GC–MS. Results: Yield of EW was approximately 71.05% (w/w). SEM at 350X – 25000X showed elongated rectangular thin flakes, globose crystalline florets (66–70 × 60-63 µm) in EW and heterogenous colloidal mass with grooves and ridges, globose crystalloid mass with folded lamellae (7.8–8 × 7.3–7.5 µm) in BW. Thermal stability of both waxes was up to 550 °C at N2 atmosphere, 2nd and 3rd weight loss at 378 °C and 451 °C in EW vis-à-vis at 370 °C and 472 °C in BW. UV–Vis in hexane showed peaks near 224 and 256 nm reflecting conjugated dienes and trienes. FTIR showed peaks of C–H bond stretches at wave no. 2900 cm−1, C–O double bond around 1730 cm−1, O–H bending in 1410–1470 cm−1, C–H for long hydrocarbon chains in 710–730 cm−1. XRD of EW showed diffraction peaks at 2θ = 19.5° and 24.2°. GC–MS detected myristic acid methyl ester, ethyl myristate, methyl palmitate in hydrolyzed and esterified EW. Conclusion: EW is found as novel natural wax similar to BW with industrial potential. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) is one of the main causes of death and disability in both civilian and military population. TBI may occur via a variety of etiologies, all of which involve trauma to the head. However, the neuroprotective drugs which were found to be very effective in animal TBI models failed in phase II or phase III clinical trials, emphasizing a compelling need to review the current status of animal TBI models and therapeutic strategies. No single animal model can adequately mimic all aspects of human TBI owing to the heterogeneity of clinical TBI. However, due to the ethical limitations, it is difficult to precisely emulate the TBI mechanisms that occur in humans. Therefore, many animal models with varying severity and mechanisms of brain injury have been developed, and each model has its own pros and cons in its implementation for TBI research. These challenges pose a need for study of continued TBI mechanisms, brain injury severity, duration, treatment strategies, and optimization of animal models across the neurotrauma research community. The aim of this review is to discuss (1) causes of TBI, (2) its prevalence in military and civilian population, (3) classification and pathophysiology of TBI, (4) biomarkers and detection methods, (5) animal models of TBI, and (6) the advantages and disadvantages of each model and the species used, as well as possible treatments. [ABSTRACT FROM AUTHOR]

A novel sulfated hierarchically porous geopolymer catalyst for the oxidation of dibenzothiophene was prepared through sequential treatment with desilication, ion-exchange and sulfation techniques. Desilication and ion-exchange treatments were aimed at the creation of hierarchical porosity and controlling the surface area of the geopolymer, while sulfation treatment was primarily done to enhance the acidity of the hierarchically porous geopolymer. The properties of the catalyst obtained after the modifications was studied by BET, NH3-TPD, SEM, TEM, XRD, FTIR and XRF analyses. As a result of the proposed sequential treatment, the activity of the geopolymer towards the oxidation of dibenzothiophene was profoundly increased and reflected in the enhanced conversion from 14 to 85%. A plausible electronic mechanism proposed for the reaction accentuated that the reaction might take place in two stages: the formation of sulfated geopolymer peroxo complex as the active catalyst and nucleophilic attack by dibenzothiophene over the peroxo complex to form the product, both were elaborated with suitable kinetic model. The interaction between dibenzothiophene and peroxo complex was considered to be of primary concern, based on which, Langmuir–Hinshelwood kinetic model was developed. Effective regeneration upto three cycles emphasized its potential to be exploited as an efficient catalyst for oxidative desulfurization. [ABSTRACT FROM AUTHOR]

With the rapid development in nanotechnology, the preparation of novel self-assembled nanoscale composite materials and their numerous environmental applications have become a promising area of research among the environmental scientists. In view of above, the present study aims at fabrication of a mesoporous nanoscale material of calcium ferrite-zirconium oxide-magnetic nanocomposite (CF-ZrO-MNC) to explore its application in adsorption-driven remediation process of tetracycline (TC). The characterisation study of the so-prepared CF-ZrO-MNC has revealed the presence of 0.1213 cc/g of mesoporous volume with a specific surface area of 95.32 m2/g. A comparative study performed between CF-ZrO-MNC, CaFe2O4 and ZrO2 nanoparticles has proven the superior adsorption capability of CF-ZrO-MNC for TC over the pure phases of parent CaFe2O4 and ZrO2 nanoparticles. The optimisation of TC adsorption process was performed by response surface methodology, which has revealed that 98.14% of TC removal can be obtained within 60 min of contact time using 4.0 g/L of CF-ZrO-MNC dose with 40.0 mg/L of TC concentration at solution pH 6.0. The kinetic and isotherm studies have presented pseudo-second-order kinetic and Freundlich isotherm model as the best-fitted models, respectively. The results of Langmuir isotherm model fitting indicated that CF-ZrO-MNC poses 92.59 mg/g of maximum TC adsorption capacity which has been proven to be highly effective as compared to previously reported adsorbents for the remediation of TC from aqueous media. [ABSTRACT FROM AUTHOR]

Enhanced thermoelectric performances have been achieved in hybrid nanocomposites of TiO2 incorporated into electrically conductive polyaniline (PANI) through a chemical polymerization process, for next-generation energy sources. Different weight percentages of TiO2 were used in hybrid nanocomposites and their charge transport properties were studied to understand the consequence of TiO2 incorporation in the PANI matrix. Aniline was used as reactant, and ammonium peroxydisulfate as polymerizing agent during synthesis process. The hybrid composites of TiO2 incorporated PANI were studied by using X-ray diffraction pattern, Fourier transform-infrared spectra and scanning electron microscopic images. The thermoelectric characteristics of this PANI-based composite were much improved as compared to pure PANI. The ordered chain structures of PANI, and the decrease of carrier hopping barrier with incorporation of TiO2 nanoparticles in the PANI chain matrix improved the charge carrier conduction and lead towards enhanced thermoelectric properties of these materials. The maximum Seebeck coefficient (S) as recorded 1.767 mV/°C, was fivefold larger as compared with pure PANI. The analysis of results reveal that these hybrid composites are potential candidates for next-generation thermoelectric generators with their light weight, environmentally friendly nature and cost-effectiveness for energy harvesting applications. [ABSTRACT FROM AUTHOR]

A new air and moisture stable PEPPSI (PEPPSI: pyridine-enhanced pre-catalyst preparation, stabilisation, and initiation) themed palladium N-heterocyclic carbene (NHC) complex [Pd(L)Br2(Py)] (1) [L: 2-flurobenzyl)-1-(4-methoxyphenyl)-1H-imidazolline-2-ylidene] was synthesized and characterized. The structure of complex 1 was determined by X-ray single-crystal analysis. The palladium center in 1 adopted a square planar geometry with carbene and pyridine ligands occupying the mutual trans position. The complex 1 was employed to catalyze the Mizoroki-Heck cross-coupling reactions of aryl bromides/iodides with styrene in water. To the best of our knowledge, this is the first report where a Pd-PEPPSI catalyst was successfully employed in aqueous-phase Mizoroki-Heck reaction. Good to excellent yields of cross-coupling products were obtained with a range of representative aryl bromides/iodides under relatively mild conditions (100 °C, 1 mol% of 1). A new palladium PEPPSI complex was synthesized, characterized and evaluated as catalyst for the Mizoroki-Heck reaction in aqueous medium. Both electron-donating and electron-withdrawing aryl halides (bromides and iodides) reacted with styrene to give corresponding coupling products in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

The effectiveness of the flux estimation techniques has been investigated over Umiam (25°40′32′′N, 91°54′06′′E, and altitude 1040 m above mean sea level), Shillong, in the Khasi hills located in north-east India. Primary dataset consists of sonic anemometer data recorded during January–February 2014 at 18 m and 30 m levels. Often, general planar fit (GPF) technique is used for long-term flux measurements using eddy covariance (EC). The three flux computation methods, namely double rotation (DR), GPF, and sector-wise planar fit (SPF) techniques have been compared in this investigation. SPF showed a reduction in the vertical wind (w) offset (b0, combination of instrument error and planar fit error) value compared to GPF. SPF minimized the planar-fit error in b0, while the instrument error was constant. The reduction of planar fit error has been seen in the computed sensible heat flux and momentum flux. Variations of 12–13% and 16–18% have been observed in the sensible heat flux and momentum flux in SPF compared to GPF. The effectiveness of SPF has been significant in the w-component estimation. An angle of attack (AA) which acts as a pivotal variable in the estimation of surface flux concentration varied between ± 6° in all atmospheric conditions. The standard deviations of horizontal and vertical velocity normalized by friction velocity (σu/u∗ and σw/u∗) as functions of atmospheric stability parameter (z/L) and obeyed a power-law relation during stable and unstable conditions. The variation in coefficients was in agreement with those estimated over flat and mountainous sites in the literature. [ABSTRACT FROM AUTHOR]

We present the temporal variation of surface-layer parameters and the turbulence kinetic energy budget over complex terrain during daytime. Data from three-dimensional fast response sonic anemometers at heights 6 m, 18 m, and 30 m above the ground are used for the analysis. Mountainous topography induces wind-direction variability over the measurement site throughout the day, which significantly influences the diurnal evolution of sensible heat flux, momentum flux, and turbulence kinetic energy. The increase and decrease of turbulence kinetic energy rely on the various production and consumption terms. Buoyancy dominates in the morning whereas in the afternoon both buoyancy and shear production contribute equally for the turbulence kinetic energy. The turbulence kinetic energy budget is also influenced by horizontal advection at the station. The correlation between turbulent decay and buoyancy (shear production) is negative (positive) in free convective conditions in the morning, whereas no correlation is observed for mixed convective conditions in the afternoon. [ABSTRACT FROM AUTHOR]

An excellent control over the charged transport process and optical properties in polyaniline has been attained through successful localization of polarons formed in the polyaniline chain. The localization of polaron in polyaniline has been achieved through its interaction with methylene blue (MB) dye. Polyaniline has been synthesized on paper substrate from aniline using FeCl3 as polymerizing agent. On optical measurement of prepared sample, a remarkable red shift in the optical band gap has been observed varying from 2.63 to 2.47 eV. The charge transport behavior as reflected from its I-V measurement shows a nice tuning in the logarithmic scale. The chemical interaction between the MB dye and the polaronic charged defect states brings this brilliant tuning in the optical and electrical properties of polyaniline. Predominantly, the intra-chain charge transport of the polyaniline backbone is affected by the MB dye interaction.ᅟ [ABSTRACT FROM AUTHOR]

A series of carboxylic acids including amino acids were protected as their corresponding fluorescent ester conjugates by coupling with an environment sensitive fluorophore 9-methylacridine. Photophysical properties of all the ester conjugates along with the protecting group have been investigated. Interestingly, the emission properties of the ester conjugates and 9-methylacridine were found to be highly sensitive to polarity, H-bonding and pH of the environment. Photolysis of all the ester conjugates was carried out using UV light above 360 nm and it was found that in every case the corresponding carboxylic acids were released in high chemical yield. Further, intercalation and the preferred binding mode of acridine-9-methanol and its ester conjugates with DNA were studied. In vitro biological studies revealed that acridine-9-methanol has good biocompatibility, cellular uptake property and cell imaging ability. [ABSTRACT FROM AUTHOR]

1-(Hydroxyacetyl)pyrene has been introduced as a new fluorescent phototrigger for alcohols and phenols. Alcohols and phenols were protected as their corresponding carbonate esters by coupling with fluorescent phototrigger, 1-(hydroxyacetyl)pyrene. Photophysical studies of caged carbonates showed that they all exhibited strong fluorescence properties. Irradiation of the caged carbonates by visible light (≥410 nm) in aqueous acetonitrile released the corresponding alcohols or phenols in high chemical (95–97%) and quantum (0.17–0.21) yields. The mechanism for the photorelease was proposed based on Stern–Volmer quenching experiments and solvent effect studies. Importantly, 1-(hydroxyacetyl)pyrene showed as a phototrigger for rapid photorelease of the biologically active molecule adenosine. In vitro biological studies revealed that 1-(hydroxyacetyl)pyrene has good biocompatibility, cellular uptake property and cell imaging ability. [ABSTRACT FROM AUTHOR]

SiGe alloy, owing to its high electron and hole mobility, has potential applications in high-speed microelectronic device technology. The optimization of such technology requires the precise determination of Ge concentration in the full range of composition and the understanding and control of the Ge-Si interdiffusion phenomenon. The most appropriate analytical technique with highest detection sensitivity (∼subparts per billion) for measuring elemental concentration is secondary ion mass spectrometry (SIMS). However, strong compositional dependence of secondary ion yield, i.e. 'matrix effect,' has always made SIMS quantification extremely difficult. A procedure for the accurate quantification of Ge concentration in molecular beam epitaxy (MBE)-grown SiGe (0< x<0.72) alloys based on MCs-SIMS approach has been proposed. The 'matrix effect' is shown to be completely suppressed for all Ge concentrations irrespective of impact Cs ion energies. The novel methodology has successfully been applied for direct quantitative composition analysis of Si/Ge multilayer structure. [ABSTRACT FROM AUTHOR]

Thin films of NiO (bunsenite) with (200) preferential orientation were synthesized on glass substrates by direct current sputtering technique in Ar+O2 atmosphere. Nanostructural properties of the NiO films were investigated by X-ray diffraction and also by atomic force microscopic (AFM) studies. Electrical and optical properties of the deposited films were investigated as a function of different partial pressure of oxygen in the sputtering gas mixture during deposition. The films showed p-type electrical conduction and the conductivity depends on the partial pressure of oxygen. The electrical conductivity (σRT) was found to be .0615 S cm−1 for films deposited with 100% O2 and its value sharply decreased with the decrease the partial pressure of O2; for example σRT for 50% O2 was 6.139 × 10−5 S cm-1. The mechanism of the origin of p-type electrical conductivity in the NiO film is discussed from the viewpoint of nickel or oxygen vacancies, which generate holes and electrons respectively. X-ray photoelectron spectroscopic studies supported the above argument. Corresponding optical properties showed that the transparency decreases with increasing oxygen partial pressure and the bandgap also decreases. [ABSTRACT FROM AUTHOR]

During routine screening, some otherwise healthy individuals who showed remarkably lower post prandial (at 2 hour) plasma glucose without any symptom were subjected to extended glucose tolerance test and a few of them to extended post meal tolerance test as well. It was observed that post prandial (at 2 hour) plasma glucose after glucose administration was significantly lower than the fasting level (p<0.05−p<0.001). However, post prandial plasma glucose at 2 hour after their usual meal exhibited a significantly higher level than the fasting and post glucose level (p<0.05−p<0.001). Glucose appears to be a stronger agent than the more natural mixed meal in these individuals in causing post prandial lowering of plasma glucose. Hence, these individuals are to be evaluated with their usual meals before considering further investigations. Like upper limit, there is the need to have a consensus lower limit of reference interval of blood glucose level. [ABSTRACT FROM AUTHOR]