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This study focuses on finding the soliton solutions for the time-fractional Kundu–Eckhaus equation and the time-fractional massive Thirring system using the Shehu Adomian decomposition method (SADM). The obtained solitons exhibit periodic shapes in some particular cases. In order to enhance the understanding of the physical characteristics, the presentation of 3D and contour plots involves the selection of specific parameter values for the solutions. To examine the influence of the fractional parameter θ on the solutions, two-dimensional graphs are additionally provided. In order to see how the fractional parameter θ impacts the solutions, 2D graphs are also presented. In order to validate and show the SADM's proficiency, we examine the proposed method with regard to fractional order via Atangana–Baleanu in Caputo sense, Caputo, and Caputo–Fabrizio. The uniqueness and convergence of the SADM are presented. The numerical simulations are discussed both numerically and graphically. The results of this research provide perspectives into the intricate dynamics of quantum field theory and help us understand the behaviour of fractional complicated nonlinear equations and their soliton solutions. [ABSTRACT FROM AUTHOR]

The development of an efficient and stable non-noble metal catalyst to replace noble metal catalyst for hydrogen evolution reaction (HER) is still a challenge. Herein, we report one-step hydrothermal method to synthesis binary hybrid material composed of MoS 2 /CoS 2 heterostructure (HS) supported on reduced graphene oxide (rGO). The coexistence of HS and rGO exhibit lower overpotential towards the HER activity with superior structural stability comparing to MoS 2 , CoS 2 and MoS 2 /CoS 2 under acidic condition. The MoS 2 /CoS 2 @rGO yielded a low overpotential of −152 mV at cathodic current density −10 mAcm−2 compared to MoS 2 , CoS 2 and MoS 2 /CoS 2 with values of −322 mV, −537 mV and −238 mV. Also, a low Tafel slope value of MoS 2 /CoS 2 @rGO (65 mVdec−1) reflects its superior performance compared to other as-synthesized catalysts. The superior activity of MoS 2 /CoS 2 @rGO attributed by conductive support of rGO and strong interaction between HS and water molecule. The avenues of active sites were triggered due to the formation of HS and electrical conductivity enhancement occurred due to the presence of carbon nanostructure, which proves that further engineering of the catalyst can reduce the overpotential drastically. [Display omitted] • MoS 2 /CoS 2 @rGO as hydrogen evolving electrocatalysts in acidic medium. • Heterostructure consist of CoS 2 nanoparticle bonded with MoS 2 nanosheet with even distribution over rGO. • MoS 2 /CoS 2 @rGO exhibited higher HER compared to standalone MoS 2 , CoS 2. • The strong interface between MoS 2 and CoS 2 along rGO made the material potential towards HER. [ABSTRACT FROM AUTHOR]

Container technology is highly significant in Information and Communication Technology (ICT) systems. To maximize container effectiveness, scaling plays a significant part. Therefore, in the fog computing framework, containers are an ideal solution for hosting and scaling services. Fog networks help to increase the number of connected devices by connecting to external gateways through the Fog of Things (FoT). It is a new approach to designing and implementing fog computing systems for the IoT. The research article aims on a novel Container with a Fog-based Scalable Self-organizing Network (CFSSN) framework and use a Self-Organizing Network based Light Weight Container (SON-LWC) algorithm for moving container services for scaling expansion. This work focuses on how to transfer service or data from container to fog and self-group network. It goes over the most recent container migration methodologies, covering both live and cold migration services. Using intelligent container improves high bandwidth efficiency and provides a solution for a scalable network. [ABSTRACT FROM AUTHOR]

Quick and efficient detection of protein fibrils has enormous impact on the diagnosis and treatment of amyloid related neurological diseases. Among several methods, fluorescence based techniques have garnered most importance in the detection of amyloid fibrils due to its high sensitivity and extreme simplicity. Among other classes of molecular probes, BODIPY derivatives have been employed extensively for the detection of amyloid fibrils. However, there are very few studies on the relationship between the molecular structure of BODIPY dyes and their amyloid sensing activity. Here in a BODIPY based salicylaldimine Schiff base and its corresponding boron complex have been evaluated for their ability to sense amyloid fibrils from hen-egg white lysozyme using steady state and time-resolved spectroscopic techniques. Both dyes show fluorescence enhancement as well as increase in their excited state lifetime upon their binding with lysozyme fibrils. However, the BODIPY derivative which shows more emission enhancement in fibrillar solution has much lower affinity towards amyloid fibrils as compared to other derivative. This contrasting behaviour in the emission enhancement and binding affinity has been explained on the basis of differences in their photophysical properties in water and amyloid fibril originating from the difference in their molecular structure. Such correlation between the amyloid sensitivity and the molecular structure of the probe can open up a new strategy for designing new efficient amyloid probes. [ABSTRACT FROM AUTHOR]

Rainfall is a key input in management of agriculture and irrigation projects and any change in this variable can influence on sustainable management of water resources, agriculture and ecosystems. Rainfall extremes motive big socioeconomic effects in Indonesia, as they're frequently followed with the aid of using disastrous events, including floods and landslides. Of precise hobby is Java Island, the most populated vicinity in Indonesia, that's susceptible to destructive flooding due to heavy rainfall. This study sought to determine the spatial and temporal variability of rainfall under past and future climate scenarios. The changes of water movement and distribution are influenced by extreme rainfall and land cover conversions. The rainfall becomes more extreme than before. The trends and patterns of extreme rainfall on Java Island, Indonesia, we were studied from 2009 to 2021 the rainy season from November to May, with January and February being the wettest months. The dry season begins from June and ends in October and also find the earthquakes and eruption days, month rainfalls. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) is a bottleneck in overall water splitting due to the involvement of the four-electron process and requires a high overpotential. This hinders the stability and durability of electrocatalysts over a longer period. Herein, we report flower-like NiCo 2 O 4 decorated on carbon nanostructures synthesized using a one-pot wet chemical method as an OER electrocatalyst in an alkaline medium. The catalytic activities were characterized by various electrochemical measurements including linear sweep voltammetry (LSV), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and turnover frequency (TOF). 90 % NiCo 2 O 4 @rGO/ f -MWCNT demonstrated a higher OER activity compared to stand-alone NiCo 2 O 4 , 90 % NiCo 2 O 4 @rGO, 90 % NiCo 2 O 4 @ f -MWCNT and 80 % NiCo 2 O 4 @rGO/ f -MWCNT. [Display omitted] • NiCo 2 O 4 @NCHy (NCO@NCHy) as oxygen-evolving electrocatalysts in an alkaline medium. • Flower-like pattern distributed onto the surface of nanocarbon hybrid. • The overpotential of the NiCo 2 O 4 @NCHy was 287 mV at a current density of 10 mA/cm2. • NiCo 2 O 4 @NCHy exhibited higher OER compared to NCO and NCO@other carbon nanostructures. • The strong interface between NCO along NCHy made the material potential towards OER. [ABSTRACT FROM AUTHOR]

The unique structure of a natural nucleic acid, calf thymus DNA, which can provide an appropriate scaffold for an efficient cascaded energy transfer among organic chromophores, has been used for the generation of bright and pure white light on UV light excitation. Two most commonly used DNA stains, 4′,6-diamidino-2-phenylindole (DAPI) and ethidium bromide (EB) have been used as a part of the donor-acceptor pairs. We have judiciously selected 10-anthracene-10-yl-3-methylbenzothiazol-3-ium chloride (AnMBTZ), an ultrafast molecular rotor, to act as a bridge between DNA bound DAPI and EB for the cascaded flow of energy. The unique molecular rotor properties of AnMBTZ and its exceptional binding ability with natural DNA help to form a distinct tri-chromophoric system in DNA template which can produce bright and pure white light on UV excitation. Detailed flow of energy from photoexcited DAPI to EB via AnMBTZ has been explored using steady state and time-resolved emission spectroscopy. Further, unique binding nature of AnMBTZ with DNA molecules has been used to modulate the colour of the emission from the present tri-chromophoric system by external stimuli, like salt and temperature. Such unique stimuli responsive multi-chromophoric system in a bio-template has great potential for different lightening applications. [ABSTRACT FROM AUTHOR]

This article focuses on the investigation of the time-fractional Sharma–Tasso–Olver equation, a crucial equation with significant relevance in various scientific domains, including nonlinear optics, quantum field theory, and the physical sciences. The natural transform decomposition approach, an efficient and innovative methodology, is used in this study. The two nonsingular kernel derivatives, such as Caputo–Fabrizio and Atangana–Baleanu in the Caputo sense, are used in the suggested technique. We considered two nonlinear cases with suitable initial conditions to show that the proposed method is accurate and works well with the existing methods. Banach's fixed point theorem is used to demonstrate the uniqueness and convergence of the solution that has been achieved. The proposed solution accurately captures the behaviour of the reported findings for various fractional orders. The obtained outcomes of the suggested approach are contrasted with those of the precise solution and other numerical techniques, including the natural transform decomposition method with Caputo derivative, the natural transform iterative method, the q-homotopy analysis Elzaki transform method, and the fractional reduced differential transform method. The outcomes of the proposed method are presented in tables and figures. The findings of this study demonstrate that the investigated technique is highly effective and precise in solving nonlinear time fractional differential equations. [ABSTRACT FROM AUTHOR]

Diseases are the major constraints in realizing the yield potential of maize. Late wilt disease (LWD) caused by Harpophora maydisis one of the recently reported and widely spreading diseases across the world. Identification of LWD resistant source is an economical and eco-friendly approach. An experiment was conducted to identify LWD resistant inbred lines by subjecting 290 inbred lines to artificial screening. The same set of lines were evaluated for yield and yield attributing traits separately. Inbred lines were subjected to screening by inoculating Harpophora maydis spore suspension to stalks. Disease severity and intensity were recorded in split opened stalks using a 1 - 9 scale. Estimates of yield and yield attributing traits were also recorded and 14 inbred lines with the disease score ≤4 were identified as resistant/tolerant. Two inbred lines namely, 78 and 32589 are both tolerant to LWD and best yielding lines which can serve as potential parents for developing hybrids. [ABSTRACT FROM AUTHOR]

Protein oligomers, which are formed due to the aggregation of protein molecules under physiological stress, are neurotoxic and responsible for several neurological diseases. Early detection of protein oligomers is essential for the timely intervention in the associated diseases. Although several probes have been developed for the detection of insoluble matured protein fibrils, fluorescent probes with emission in the near infrared (NIR) region for probing protein oligomers are very rare. In the present study we have designed and synthesized a glucose-conjugated BODIPY dye with emission in the NIR spectral range. Our detailed studies show that the new probe is not only capable of detecting matured fibrils but can also probe the formation of oligomers from the native protein. The new probe shows a large increase in its emission intensity upon association with oligomers and matured fibrils. Hence, the present probe has a great potential for the in vivo imaging of protein oligomers and matured fibrils. Detailed spectroscopic properties of the new probes in molecular solvents have been performed to understand its oligomers- and fibril- sensing mechanism. Unlabelled Image [ABSTRACT FROM AUTHOR]

DAPI is used extensively to identify and quantify DNA in cellular systems assuming its exclusive staining of nucleic acids. However, the present results show that DAPI has much higher affinity towards protein aggregates than DNA. Thus, the use of DAPI for the nucleic acid assay of cellular systems with protein aggregates may not be very reliable. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Photophysical properties of a ratiometric amyloid probe have been investigated. • Role of solvent polarity and solute‐solvent H‐bonding on the amyloid sensing behavior of the sensor has been understood. • H-bonding with solvent leads to molecular twisting resulting large decrease in emission yield in polar protic solvents. Abstract Detailed photophysical properties of 2-[2′-Me,4′-(dimethylamino)-phenyl]benzothiazole (2Me-DABT), a potential ratiometric amyloid fibril sensor, have been investigated in different solvents and solvent mixtures using steady state and time-resolved spectroscopic techniques. Our studies show that emission properties of 2Me-DABT are significantly modulated by polarity of solvent media. Extent of solvatochromism (3585 cm−1) shown by 2Me-DABT is quite large and can be used to monitor micropolarity of different complex media. Further, Stokes' shift (>10,000 cm−1) shown by 2Me-DABT in all studied solvents is also much larger than most common molecular probes. It has also been shown that hydrogen bonding with solvent molecules results in large modulation in photophysical properties of 2Me-DABT. The H-bonding with water molecules induces a large change (39°) in the dihedral angle between benzothiazole and aniline moieties resulting large changes in photophysical properties of 2Me-DABT in polar protic solvents. Photophysical properties reported herein are used to explain observed amyloid sensing behaviour of 2Me-DABT. Detailed quantum chemical calculations are performed to support the experimental results. [ABSTRACT FROM AUTHOR]

[Display omitted] • Understanding the effects of intra- and intermolecular interactions in zwitterionic complexes with cyclodextrins. • The fluorescence enhancement of the weakly bound SYPRO Orange (SO)/β-cyclodextrin complex is higher than the strongly bound SO/Captisol. • Incorporating both segmental mobility and charge transfer properties improves molecule binding affinity over having only one of these properties. • Stimuli-dependent emissions can be useful for drug delivery applications. The differential complexation studies with cyclodextrins and their charged derivatives have been well studied using cationic, anionic, as well as neutral guest molecules. However, supramolecular complexation with zwitterionic guest molecules is quite limited. Zwitterions are overall neutral molecules with localized charges that can offer additional site-specific electrostatic interaction with cyclodextrins as compared to neutral guest molecules. There is no information on how the different intra- and intermolecular interactions can modulate the binding of a zwitterion with a macrocyclic host. Herein, the supramolecular interactions of biologically important zwitterionic amyloid probe, SYPRO Orange (SO) with β-cyclodextrin (β-CD) and sulfobutylether β-cyclodextrin (SBE-β-CD, Captisol®) have been evaluated and compared using different spectroscopic methods. SO forms inclusion complexes with both β-CD and SBE-β-CD which led to the enhanced fluorescence along with a hypsochromic shift in its emission spectra. It has been shown that the presence of segmental rotation in a guest molecule with charge transfer property favours its association with the macromolecules. The fluorescence enhancement and the binding affinities show contrasting behavior in these two types of host–guest complexes. Time-resolved emission measurements could disentangle the contribution from different inclusion complexes. Ionic strength and temperature variation in the photophysical properties helped to understand the molecular interactions involved in such contrasting behavior. [ABSTRACT FROM AUTHOR]

We report a facile, one pot solvothermal route to prepare ultrathin molybdenum disulfide supported on nanocarbon hybrid (MoS 2 @NCHy) network with varied mass loading of MoS 2 (20 wt%, 40 wt% and 60 wt%) for catalyzing hydrogen evolution reaction (HER). A large current density of −451 mAcm −2 at an overpotential of −480 mV vs. RHE, proves 40 wt% MoS 2 @NCHy/GCE nanocomposite as a highly HER active catalytic material. This value was found to be 50 times, 6 times and 2.5 times higher compared to MoS 2 /GCE (−8 mAcm −2 ), 20 wt% MoS 2 @NCHy/GCE (−75 mAcm −2 ) and 60 wt% MoS 2 @NCHy/GCE (−180 mAcm −2 ) respectively. Meanwhile, η 10 (overpotential required to attain a current density of −10 mAcm −2 ) is −186 mV for 40 wt% MoS 2 @NCHy/GCE, which is much lower to MoS 2 /GCE (−498 mV), NCHy/GCE (−334 mV), 20 wt% MoS 2 @NCHy/GCE (−264 mV) and 60 wt% MoS 2 @NCHy/GCE (−204 mV). The overall activity of the catalyst was manifested by the least overpotential, η 10  = −186 mV vs. RHE, Tafel slope of 53 mVdec −1 and exchange current density ( j 0 ) of 6.3 × 10 −2  mAcm −2 . The superior performance of 40 wt% MoS 2 @NCHy should be attributed to the highly conductive and porous support of three dimensional NCHy architecture as well as the enlarged interlayer spacing of MoS 2 . This study paves a new paradigm to exploit the synergistic effect of MoS 2 and NCHy resulting in strong electronic coupling for enhancement in the HER activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • One added proton introduces barrierless torsional motion in the excited state of julolidine based molecule. • Added proton makes the molecule a superior viscosity sensor. • Photoisomerization process in the excited state gets suppressed upon protonation. Molecular rotors are widely used in real time determination of microviscosity of different biological systems and materials. An excited state non-radiative barrierless bond twisting process is primarily responsible for their response towards the surrounding viscosity. Any control over such bond twisting process is useful in developing molecular rotor based sensors. Present work shows that the simple addition of a proton results in the suppression of the isomerization process and emergence of a barrierless ultrafast bond twisting process in the excited state of a julolidine based molecule. The appearance of such a new and efficient non-radiative process makes the protonated molecule highly sensitive to its surrounding viscosity. Such proton driven change in the excited state dynamics is a manifestation of the large modulation in the excited state potential energy surface by the added proton. [ABSTRACT FROM AUTHOR]

The fluoren-9-one (FL) molecule, with a single hydrogen bond-accepting site (CO group), has been used as a probe for investigation of the dynamics of a hydrogen bond in its lowest excited singlet (S1) state using the subpicosecond time-resolved visible pump-IR probe spectroscopic technique. In 1,1,1,3,3,3-hexafluoroisopropanol (HFIP), a strong hydrogen bond-donating solvent, the formation of an FL-alcohol hydrogen-bonded complex in the ground electronic (S0) state is nearly complete, with a negligible concentration of the FL molecule remaining free in solution. In addition to the presence of a band due to the hydrogen-bonded complex in the transient IR spectrum recorded immediately after photoexcitation of FL in HFIP solution, appearance of the absorption band due to a free CO stretch provides confirmatory evidence of ultrafast photodissociation of hydrogen bonds in some of the complexes formed in the S0 state. The peak-shift dynamics of the CO stretch bands reveal two major relaxation pathways, namely, vibrational relaxation in the S1 state of the free FL molecules and the solvent reorganization process in the hydrogen-bonded complex. The latter process follows bimodal exponential dynamics involving hydrogen bond-making and hydrogen bond-reorganization processes. The similar lifetimes of the S1 states of the FL molecules, both free and hydrogen-bonded, suggest establishment of a dynamic equilibrium between these two species in the excited state. However, investigations in two other weaker hydrogen bond-donating solvents, namely, trifluoroethanol (TFE) and perdeuterated methanol (CD3OD), reveal different features of peak-shift dynamics because of the prominence of the vibrational relaxation process over the hydrogen bond-reorganization process during the early time. [ABSTRACT FROM AUTHOR]

Early detection of amyloid fibrils is very important for the timely diagnosis of several neurological diseases. Thioflavin-T (ThT) is a gold standard fluorescent probe for amyloid fibrils and has been used for the last few decades. However, due to its positive charge, ThT is incapable of crossing the blood-brain barrier and cannot be used for in vivo imaging of fibrils. In the present work, we synthesized a neutral ThT derivative, 2-[2'-Me,4'-(dimethylamino)phenyl]benzothiazole (2Me-DABT), which showed a strong affinity towards the amyloid fibrils. On association with the amyloid fibrils, 2Me-DABT not only showed a large increase in its emission intensity, but also, unlike ThT, a large blueshift in its emission spectrum was observed. Thus, unlike ThT, 2Me-DABT is a potential candidate for the ratiometric sensor of the amyloid fibrils. Detailed photophysical properties of 2Me-DABT in amyloid fibrils and different solvent media were studied to understand its sensory activity. Fluorescence resonance energy transfer (FRET) studies suggested that the sites of localization for ThT and 2Me-DABT in amyloid fibrils are not same and their average distance of separation in amyloid fibrils was determined. The experimental data was nicely supported by molecular docking studies, which confirmed the binding of 2Me-DABT in the inner core of the amyloid fibrils. [ABSTRACT FROM AUTHOR]

PicoGreen, a cyanine based ultrafast molecular rotor, shows high affinity towards amyloid fibrils and scores a much better sensitivity than Thioflavin-T, a gold standard probe for amyloid fibrils. Detailed spectroscopic and molecular docking studies have been performed to understand the mode of interaction between PicoGreen and amyloid fibrils. [ABSTRACT FROM AUTHOR]

Ultrafast molecular rotors (UMRs) are reported to be one of the best fluorescent sensors to study different microenvironments, including biomolecules. In the present work, we have explored the possibility of application of a julolidine-based neutral UMR, 9-(2,2-dicyano vinyl) julolidine (DCVJ), as a DNA sensor and studied its mode of binding with DNA in detail using spectroscopic and molecular docking techniques. Our spectroscopic studies indicate that association of DCVJ with DNA leads to a very large enhancement in its emission intensity. Detailed investigation reveals that, despite being a neutral molecule, binding of DCVJ with DNA is largely modulated in the presence of salt. Such an unusual salt effect has been explained by invoking the ion-dipole interaction between DCVJ and the phosphate backbone of DNA. The ion-dipole interaction has also been established by studying the interaction of DCVJ with nucleosides. Detailed time-resolved studies show that the twisting motion around the vinyl bond in DCVJ gets retarded to a great extent because of its association with DNA molecules. Through competitive binding studies, it has also been established that DCVJ also binds to DNA through intercalation. Finally, quantum chemical calculations and molecular docking studies have been performed to confirm the mode of binding of DCVJ with DNA. [ABSTRACT FROM AUTHOR]

[Display omitted] • Surfactant induced deaggregation leads to high solubility of PM597 dye in water. • Emission yield and lifetime of PM597 in surfactant solution is significantly higher than ethanol. • Excited state non-radiative ring puckering process in photoexcited PM597 is suppressed by surfactant. • The lasing performance of PM597 is demonstrated in aqueous solution and its efficiency is comparable to ethanol. • Present result shows a great promise towards water-based dye lasers, especially for dyes that are completely non-emissive in water. Water is being considered as an economical, safe and environmental friendly alternative solvent for dye lasers. However, the use of water in dye laser is restricted due to the formation of non-emissive aggregates of dye molecules. In the present study we have explored the possibility of the use of commercially available surfactant molecules for the water based laser of Pyrromethene 597 (PM597) dye, which has emerged as an alternative for more commonly used Rhodamine dyes in dye laser systems. Our studies show that in water, PM597 forms non-emissive aggregates which can be dissociated into monomeric dye molecules by adding common surfactants. Further, the high microviscosity in the micellar media retarded energy wasting ring puckering process in the excited state of the dye leading to the increase in its emission yield and excited state lifetime to a significant extent. It has been demonstrated that the emission yield and excited state lifetime in surfactant solution is relatively higher than in ethanol, the most commonly used organic solvent for dye lasers. Lasing action has been demonstrated in the aqueous solution of dye and lasing efficiency is found to be comparable to ethanol. [ABSTRACT FROM AUTHOR]

In this article, optical soliton solutions of the time fractional Biswas–Milovic equation obtained by employing Shehu Adomian Decomposition Method (SADM). We study the projected model in terms of fractional order employing Caputo (C), Caputo–Fabrizio (CF), and Atangana–Baleanu in Caputo sense (ABC) derivatives to validate and demonstrate the competency of proposed techniques. Convergence and uniqueness of the proposed techniques are analysed. The numerical simulations are carried out and compared with the existing methods. Moreover, We depicted the 2-D,3-D and contour graphs to illustrate the behaviour of obtained solutions. • Optical soliton solutions of nonlinear time fractional Biswas–Milovic equation studied. • The fractional derivative considered with singular and non-singular kernels. • Convergence and uniqueness presented. • Proposed technique compared with those existing methods. • Solution phenomena presented graphically. [ABSTRACT FROM AUTHOR]

Triblock copolymer and surfactant based supramolecular assemblies have been used for the controlled sequestration of the DNA intercalator. The triblock copolymer micelles do not affect the molecules that are intercalated in the DNA. However, on addition of charged surfactant to the triblock copolymer micellar solution, sequestration of the intercalated molecules from DNA to the polymer-surfactant supramolecular assemblies takes place. Such sequestration of the intercalated molecules in the polymer-surfactant supramolecular assemblies has been explained on the basis of the charged surface formed in the polymer micelles due to the addition of surfactants. Sequestration of the intercalated molecules from the DNA to the polymer-surfactant supramolecular assemblies has been monitored through the ground state absorption, steady state, and time-resolved emission measurements. It is shown that the extent of sequestration of the intercalated molecules can be finely tuned by tuning the concentration of the surfactant in the triblock copolymer solution. Quantitative sequestration of the intercalated molecules by the supramolecular assemblies has been achieved. Such controlled sequestration of the DNA intercalated molecules by polymer-surfactant supramolecular assemblies can be used to study the binding of drug with DNA and may be useful in applications like detoxification in the case of drug overdose. [ABSTRACT FROM AUTHOR]

Background & objectives: Endothelial cells of the donor cornea are known to be affected quantitatively and qualitatively in different pathological conditions after penetrating keratoplasty (PK) and this has direct effect on the clarity of vision obtained after PK. This study was undertaken to analyze the qualitative and quantitative changes in donor endothelial cells before and after PK in different pathological conditions. Methods: A prospective investigational analysis of 100 consecutive donor corneas used for penetrating keratoplasty between June 2006 and June 2008, was conducted. The patients were evaluated on the first day, at the end of first week, first month, third and six months and one year. Results: A decrease was observed in endothelial cell count in all pathological conditions. After one year of follow up the loss was 33.1 per cent in corneal opacity, 45.9 per cent in acute infective keratitis (AIK), 58.5 per cent in regrafts, 28.5 per cent in pseudophakic bullous keratopathy (PBK), 37 per cent in descemetocele, 27 per cent in keratoconus and 35.5 per cent in aphakic bullous keratopathy (ABK) cases. Interpretation & conclusions: The endothelial cell loss was highest in regraft cases which was significant (P<0.05), while the least endothelial cell loss was seen in keratoconus cases. The cell loss was associated with increase in coefficient of variation (CV), i.e. polymegathism and pleomorphism. Inspite of this polymegathism and pleomorphism, the clarity of the graft was maintained. [ABSTRACT FROM AUTHOR]

The short wave direct Aerosol Radiative Forcing (ARF) at a semi urban coastal location near Chennai (12.81 °N, 80.03 °E, ∼45 m amsl), a mega city on the east coast of India has been estimated for all the four seasons in the year 2013 using the SBDART (Santa Barbara Discrete ordinate Atmospheric Radiative Transfer) model. As inputs to this model, measured aerosol parameters together with modeled aerosol and atmospheric parameters are used. The ARF in the atmosphere is found to be higher in the pre-monsoon and winter seasons compared to the other seasons whereas at the surface, it is found to be higher in the south-west (SW) monsoon and winter seasons. The estimated ARF values are compared with those reported over other locations in India. The effect of Relative Humidity on ARF has been investigated for the first time in the present study. It is found that the ARF increases with increasing RH in the SW monsoon and winter seasons. An unique feature of the present study is the comparison of the net surface short wave fluxes estimated from the model (SBDART) and measured fluxes using CNR 4 net radiometer. This comparison between the estimated and measured fluxes showed good agreement, providing a ‘closure’ for the estimates. [ABSTRACT FROM AUTHOR]

The emission properties of Thioflavin-T (ThT), a cationic molecular rotor, have been investigated in two fluoroalkylphosphate ([FAP]) anion based ionic liquids, namely, 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate and 1-(2-hydroxyethyl)-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate, over a wide temperature range. The micro-viscosities of ionic liquids around ThT, measured from the emission quantum yield, are found to be quite different from their bulk viscosities. The temperature dependence of the viscosity and the emission quantum yield reveals that, despite the very low shear viscosity of these ILs, the non-radiative torsional relaxation has a strong dependence on the free volume of these [FAP] anion based ILs. [ABSTRACT FROM AUTHOR]

In this communication, using sub-picosecond resolved fluorescence upconversion spectroscopy, we discover that despite a large fluorescence enhancement observed for thioflavin-T in insulin fibrils, the majority of fibril bound thioflavin-T undergoes efficient ultrafast conformational relaxation, and thus does not contribute to the characteristic fluorescence enhancement. [ABSTRACT FROM AUTHOR]

• The vibrational dynamics of tungsten hexacarbonyl, W(CO) 6 , has been studied in two FAP based superhydrophobic ILs. • The vibrational lifetime and anisotropy remains indistinguishable for difference in ionic liquids. • Ultrafast 2D-IR spectroscopy demonstrates the variation in FFCF of ILs assigned to ion-rattling and ion-cage motions. • The neutral and hydrophobic probe, W(CO) 6 provides an opportunity to understand the local structural dynamics of FAP ILs. Ultrafast two-dimensional infrared spectroscopy (2D-IR) measurements for tungsten hexacarbonyl, W(CO) 6 , has been performed in two fluoroalkylphosphate ([FAP])-based ultrahigh hydrophobic, ionic liquids, namely, 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)-trifluorophosphate ([EMIM][FAP]) and 1-(hexyl)-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate ([HMIM][FAP]) to probe their local structure and dynamics. To understand the effect of FAP anion on the dynamics, a relatively less hydrophobic [PF 6 -] anion has been introduced in the form of [HMIM][PF 6 ]. While the linear IR spectra records some influence of anion in terms of spectral shifts, the alkyl chain length of the cation seems to have no significant influence on the spectral peak position; and even the spectral broadening is found to be in the similar range. Further, vibrational population relaxation dynamics and vibrational anisotropy decay also does not show any significant variation due to difference in constituent of these ionic liquids as well as its solvent properties, such as, viscosity. Finally, 2D-IR spectra show large variation in the spectral shapes with waiting times, which qualitatively remains similar in all the tested ionic liquids. The frequency-fluctuation correlation function measured from 2D-IR spectra displays a bi-exponential decay with the shorter time-constant dependent on the identity of the anion, and has been attributed to the ion-rattling motion, whereas, the longer component has been found to be invariant with the identity of ionic liquid, and has been attributed to ion-cage motions which is in line with previous MD simulations as well as previous experimental measurements, using ionic vibrational probe. Overall, 2D-IR spectroscopy, in combination with this neutral and hydrophobic probe, W(CO) 6 provides a unique opportunity to understand the local structural dynamics of this ultrahigh hydrophobic ionic liquid which are otherwise not accessible by hitherto explored ionic vibrational probes. [ABSTRACT FROM AUTHOR]

The possibility of intermolecular photoinduced ET (PET) is investigated in a novel donor–acceptor (D–A) system consisting of zinc tetraphenylporphyrin (ZnTPP) as donor and 2-nitrofluorene (2NF) as acceptor upon photoexcitation of the former moieties in polar solvent acetonitrile (ACN). The observed values (7.23 × 10 9 L/(mol s) and 7.04 × 10 9 L/(mol s)) of the fluorescence quenching rate constant from steady state and time-resolved data, respectively, are in good agreement with that (5.65 × 10 9 L/(mol s)) obtained from Marcus theory. Excited state absorption (ESA) from the S 2 state of Soret excited ZnTPP to higher electronic states gives rise to broad transient absorption spectra in 560–700 nm region. Presence of 2NF leads to a faster decay (up to 100 ps time delay) of the ESA signal of ZnTPP at a probe wavelength of 620 nm. This indicates ultrafast ET from the S 2 state (zero vibrational level) as well as the higher vibrational levels of the S 1 state of ZnTPP to 2NF. Moreover, transient absorption kinetics at longer time delays (up to 7 ns) at a probe wavelength of 620 nm show the formation of a charge separated state due to ET from the S 1 state (zero vibrational level) of the Soret excited ZnTPP to 2NF. [ABSTRACT FROM AUTHOR]

The aggregation of proteins into the amyloid fibrils is mainly responsible for several neurological diseases. Knowledge of dynamics in amyloid fibril is very essential to understand its biological activity. Although, the effects of environment like pH, ionic strength, temperature, etc. on the fibril have been studied extensively, studies on the dynamics of amyloid fibril and the role of water in fibril are scarce. In this article, we have reported the results on the excited state dynamics of amyloid fibrils formed by a well-known blood plasma protein, human serum albumin (HSA), at neutral pH. The sole tryptophan residue, W214, has been used as the intrinsic fluorescent probe to monitor its excited state dynamics. Steady-state and time-resolved fluorescence data suggests that the W214 becomes more closer to the quencher amino acid residues in the fibrillar phase than in the native protein. From detailed time-resolved emission measurements, it is shown that despite having a more ordered structure, the water molecules around W214 in amyloid fibril is more labile than that in the native protein. Fluorescence depolarization studies also indicate that the W214 residue is located in a relatively more flexible region of the ordered amyloid fibril than that in the native protein. [ABSTRACT FROM AUTHOR]

Benzothiazole based ultrafast molecular rotor, Thioflavin T (ThT), is a well known fluorescence sensor for nucleic acids. Thus, the knowledge of mode of interaction between ThT and DNA is very important for efficient utilization of such fluorescence sensors. In the present article, we have reported detail studies on the mode of interaction between ThT and a natural DNA using steady-state and femtosecond time-resolved transient emission techniques. Detail steady-state studies show that ThT binds strongly with natural DNA and causes a large change in its spectroscopic properties. Femtosecond transient emission studies show a substantial decrease in the torsional motion in the excited state of ThT bound to DNA molecules, indicating a strong interaction between them. It is observed that ThT binds to DNA through two modes of interaction. Studies with salt indicate that large fraction of ThT binds to DNA by electrostatic interaction, whereas, viscosity and resonance energy transfer studies indicate the intercalation of ThT with DNA molecules. [ABSTRACT FROM AUTHOR]

The scattering and absorption components of Aerosol Optical Depth (AOD) over a semi-urban coastal location (12.81°N, 80.03°E) near the mega city Chennai in peninsular India are separated using the collocated measurements of Black Carbon concentration and Atmospheric Boundary Layer Height (ABLH) from ERA Interim Reanalysis data assuming that most of the BC is contained and homogeneously mixed in the ABL. It is found that the absorption component to scattering component ratio has a strong seasonal variation with a pronounced maximum in the South West (SW) monsoon season. This is indicative of more effective wet removal of scattering aerosols than absorbing (BC) aerosols. There could also be an effect due to preferential removal of large particles which would have a lower content of BC. The Angstrom wavelength exponent shows a minimum in the SW monsoon season, the minimum being more pronounced for the scattering aerosols implying relative dominance of coarse mode particles. Investigation of the effect of Relative Humidity on scattering and absorption components of AOD revealed that the BC (absorbing) aerosols are non-hydrophilic/not coated with hydrophilic substance. [ABSTRACT FROM AUTHOR]

The possible role of photoinduced electron transfer is investigated in the fluorescence quenching of the donors metallo-octaethylporphyrins (zinc octaethylporphyrin and magnesium octaethylporphyrin) in presence of the acceptor 2-nitrofluorene in polar acetonitrile liquid medium by using steady state and time-resolved techniques at the ambient temperature (300 K). The donors are selectively excited at the Q band (S1 state), where 2-nitrofluorene has negligible absorbance. The observed bimolecular fluorescence quenching rate constants for the present donor--acceptor systems from steady state as well as time-resolved fluorescence quenching data are of the order of 1010 L/(mol s) (less than the diffusion-controlled limit of 1.9 x 1010 L/(mol s)). The moderately negative values of Gibbs free energy change (ΔG°) indicate that photoinduced electron transfer from the metallo-porphyrins to 2-nitrofluorene in acetonitrile solvent is possible upon photoexcitation of the former molecules. Moreover, the fluorescence quenching rates for both the donor--acceptor systems obtained from Marcus theory agree quite well with the observed values from fluorescence quenching measurements (especially time-resolved measurements). [ABSTRACT FROM AUTHOR]

Highlights: [•] Spectral characteristics of porphyrins are affected by solvent polarizability. [•] Ground state dipole moments of porphyrins are found to be very low. [•] Solvatochromic Stokes’ shift method is used to find excited state dipole moment. [•] The first excited singlet state of porphyrins possesses moderate dipole moments. [•] Other properties of porphyrins are nearly insensitive to solvent polarity. [ABSTRACT FROM AUTHOR]

Regular measurements of Black Carbon (BC) aerosol mass concentration have been carried out since March 2011 at a tropical location (12.81°N, 80.03°E) adjoining the mega city, Chennai, on the east coast of India for the first time. As this region is influenced by both the South West and North East monsoons, the BC observations at this site assume importance in understanding the overall BC distribution over India. The data collected until August 2012 has been examined for the general and regionally distinctive features. Spectral absorption characteristics reveal that the BC is mainly from fossil fuel based emissions. The BC concentration shows significant diurnal variation only in the North East monsoon and winter seasons with night time concentration considerably higher than the day time concentration. In the other seasons the day–night contrast in BC is not significant. Seasonal variation is rather subdued with a broad maximum during the Northeast monsoon and winter months and a minimum during the southwest monsoon months. The observed diurnal and seasonal variations are examined in the light of local Atmospheric Boundary Layer dynamics and long range transport. For the first time, an inverse relationship has been established between BC and ABL height on a quantitative basis. A distinctive feature of the region is that in all the seasons transport pathways have long continental overpasses which could lead to the suppressed seasonal variation. It is found that the BC over this region shows distinct diurnal and seasonal features compared to those reported for other coastal and inland regions in India. [ABSTRACT FROM AUTHOR]

Highlights: [•] Femtosecond excited state dynamics of 1-nitropyrene, an environmental pollutant, has been studied. [•] Experimentally for the first time it has been shown that rotation of the nitro group in nitropyrene takes place in its photoexcited state. [•] In protic solvent, due to solute–solvent H-bonding interaction, rotation of the nitro group is absent. [ABSTRACT FROM AUTHOR]

This paper applies differential transform - Pade technique for treating non-linear singular boundary value problems arising in various physical problems of science and engineering. Comparisons are made between the results of the proposed method, and the exact solutions. The results show that the proposed method is an attractive method for solving non-linear singular boundary value problems. [ABSTRACT FROM AUTHOR]

Thisarticle reports the synthesis and characterization of severalnew fluorinated sulfonated poly(arylene ether sulfone) (6FBPAQSH-XX). The structures of the prepared copolymers were confirmedby FTIR and NMR spectroscopy. The copolymers showed high molecularweight, good solubility, and film-forming capabilities. The copolymersexhibited high thermal and oxidative stability and good mechanicalproperties depending upon their chemical compositions. Transmissionelectron microscopy (TEM) showed cluster like microstructures forthe copolymer membranes suggesting good phase separated morphology.The cluster size increased with increasing mole percentage of sulfonatecomonomer and was in the range of 5–65 nm. The copolymers showedgood dimensional stability with very low water uptake and swellingratios. Ion exchange capacity (IECW) of the copolymer filmswas determined by titration methods and was also calculated from themonomer composition obtained by 1H NMR spectroscopy. Theproton conductivities of acid form membrane increased with IECWvalue and temperature, with maximum to 108 mS/cm at 90 °Cfor 6FBPAQSH-60 copolymer. [ABSTRACT FROM AUTHOR]

Background: Microscopy detection of acid fast bacilli (AFB) by Ziehl-Neelsen (ZN) method has many advantages when it comes to speed and feasibility though it has a low sensitivity. If the sensitivity could be improved, it has the potential to become an even more valuable tool for detection of AFB. Objectives: To evaluate the efficacy of bleach concentration method in the cytodiagnosis of tuberculous lymphadenitis in comparison with routine Ziehl-Neelsen method and to compare the positivity in various cytomorphological categories. Materials and Methods: A total of 112 cases of tuberculous lymphadenitis diagnosed by fine needle aspiration cytology (FNAC) were categorized into six cytomorphological patterns. The acid-fast bacilli positivity by routine staining was correlated with modified bleach methods of ZN staining. Sensitivity of routine ZN and modified bleach concentration was compared. Results: The classic cytomorphological pattern of tuberculosis of epithelioid granulomas, langhans giant cells and caseous necrosis was seen in 37.5% of cases. Routine ZN staining detected AFB in 12.5% of cases and the modified bleach method in 60.7%. Modified bleach method showed AFB positivity in additional 54 cases where routine AFB staining was negative. The modified bleach method showed AFB positivity in all cases where routine ZN staining was positive. Conclusion: The modified bleach method was more sensitive and safer than routine ZN staining. As the background was clear, the bacilli were easily visible and the screening time was shorter. [ABSTRACT FROM AUTHOR]

Time-resolved emission measurements in subpicosecond time domain have been carried out for 1-nitropyrene in different solvents to understand the mechanism for the observed ultrafast decay of its first excited singlet state. Excited-state dynamics of 1-nitropyrene is found to be independent of the solvent viscosity. This result contradicts the proposition in the literature (J. Phys. Chem. A 2007, 111, 552) that the ultrafast decay in 1-nitropyrene is due to the large amplitude torsional motion of the nitro group around the pyrene moiety. Excited-state dynamics of 1-nitropyrene in solvents with different dielectric constants shows that excited-state lifetime suddenly increases after a certain value of the dielectric constant. Detailed quantum chemical calculations have been carried out to understand the process that is responsible for the observed effect of the dielectric constant on the excited-state dynamics of 1-nitropyrene. It is seen that the excited-state lifetime and the singlet--triplet energy gap follow similar variation with the dielectric constant of the medium. Such a correlation between the excited-state lifetime and the singlet--triplet energy gap supports the fact that the observed ultrafast decay for 1-nitropyrene is due to an efficient intersystem crossing rather than to the torsional motion of the nitro group as proposed in the literature. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to prepare and characterize nanometer-sized prodrug (nanoprodrug) of camptothecin. The camptothecin prodrug was synthesized using tetraethylene glycol spacer linked via carbonate bond to camptothecin and via ester bond to α-lipoic acid. The nanoprodrug was prepared through the spontaneous emulsification mechanism using the mixture of camptothecin prodrug and α-tocopherol which served as a structural matrix. The nanoprodrug was activated readily by porcine liver esterase and, with a much slower rate, by hydrolytic degradation. Upon longterm storage, the α-lipoic acid moiety of the camptothecin prodrug gradually oxidized without loss of structural integrity and therapeutic efficacy. Interestingly, the hydrolytic activation was negligible before the oxidation, but was significantly accelerated after the oxidation of the α-lipoic acid moiety, suggesting an oxidative stimuli-responsive activation of the prodrug. The camptothecin nanoprodrug was found to possess significant inhibitory effect on the proliferation of U87-MG glioma cells with an IC50 of 20nM. [ABSTRACT FROM AUTHOR]

Abstract: This paper applies He’s variational iteration method for solving nonlinear singular boundary value problems. The solution process is illustrated and various physically relevant results are obtained. Comparison of the obtained results with exact solutions shows that the method used is an effective and highly promising method for treating various classes of both linear and nonlinear singular boundary value problems. [Copyright &y& Elsevier]

Background: Monophasic fibrous synovial sarcoma (SS) is the most common variant of SS. Only a few cytological studies are available on this entity. Bcl-2 protein expression has been described as a characteristic marker of SS and is useful for its differentiation from other sarcomas. Cytokeratin and CD99 are also used in detecting SS. Aims: To evaluate synovial sarcoma and its variants cytomorphologically. Materials and Methods: During a period of 10 years 7 months, i.e. from January 1998 to July 2008, 12 cytologic specimens diagnosed as synovial sarcoma were reviewed. Ten cases were diagnosed as SS on aspiration alone but two cases required ancillary technique i.e., immunocytochemistry staining with bcl-2 and cytokeratin. The smears were stained with Papanicolaou and May-Grünwald-Giemsa stains. Results: All cytologic specimens in our study had similar appearance. Most smears were highly cellular and were made up of densely packed tri-dimensional groups and singly scattered round to oval cells. Cellular monomorphism and vascular channels within the cell groups were the remarkable findings. Only one case showed cytologic evidence of epithelial differentiation. Bcl-2, cytokeratin, CD99 positivity was seen on immunohistochemistry staining. Results were categorized according to age, sex and morphologic variants. Conclusions: Although cytomorphologic features of synovial sarcomas are characteristic enough to permit its recognition, clinical correlation is necessary for accurate diagnosis. Monophasic variant is the most common entity observed in the present study. [ABSTRACT FROM AUTHOR]

We report a case of QuantiFERON TB-Gold conversion associated to Mycobacterium gordonae in an elderly male from an assisted living facility without known risk factors for tuberculosis. This knowledge of environmental mycobacteria causing positive quantiferon assays is important to avoid unnecessary treatment of false-positive latent tuberculosis, especially in the absence of well-established positive predictive value of quantiferon conversion. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, He’s variational iteration method is applied to solve twelfth-order boundary-value problems. The numerical results obtained with minimum amount of computation are compared with the exact solutions to show the efficiency of the method. The results show that the variational iteration method is of high accuracy, more convenient and efficient for solving high-order boundary-value problems. [Copyright &y& Elsevier]

Amyloid fibrils, an aggregated form of proteins, are responsible for different types of neurological diseases. A constant effort is there for the search of a sensitive and selective probe for amyloid fibrils. Recently, it has been shown that a zwitterionic merocyanine dye, SYPRO Orange, can detect the amyloid fibrils with much higher sensitivity and with much preferred spectroscopic properties than present gold standard amyloid probe, Thioflavin T. In the present work, we have investigated the detailed photophysical properties of SYPRO Orange in different molecular solvents and solvent mixtures with wide range of properties to disentangle the fundamental processes that are responsible for its amyloid sensing activity. It has been shown that SYPRO Orange forms aggregates in water and results in extremely low emission quantum yield. The amyloid induced de-aggregation of SYPRO Orange is primarily responsible for enormous increase in its emission intensity upon binding with amyloid fibrils. Photophysical studies using steady state and time-resolved emission spectroscopy further enlighten us on the role of solvent polarity, solute-solvent H-bonding and solvent viscosity on its sensitivity towards amyloid fibrils. Thus, present results will be quite useful for the use of SYPRO Orange in different other spectroscopic applications. • Detailed photophysics of SYPRO Orange has been investigated to understand its amyloid sensing mechanism. • Steady state and time-resolved emission studies show that SYPRO Orange mainly exist in the aggregated form in water. • The role of amyloid induced de-aggregation is the first step in its amyloid sensing process. • H-bonding, low polarity and high viscosity at amyloid groove is responsible for its high emission yield in fibrils. [ABSTRACT FROM AUTHOR]