Publications by authors named "Ramasamy E"

Article Synopsis
  • * Researchers analyzed field and laboratory populations of Z. cucurbitae from Bangalore, India, identifying ten types of RNA viruses, with different infection profiles in the two populations indicating the potential for covert infections.
  • * The study further contributed to understanding the RNA virus diversity in Indian Z. cucurbitae populations and revealed persistent infections in lab settings, with additional discoveries of virus genomes in populations from Eastern Asia and Hawaii.
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The study focuses on the occurrence, abundance and characteristics of microplastics (MPs) in the subsurface and bottom waters of Vembanad Lake, a Ramsar site in the state of Kerala. Even though several studies elucidate the prevalence of microplastic pollution in the surface waters of aquatic ecosystems, a little is known about the vertical distribution of MPs in the water column. Vembanad Lake water is greatly affected by microplastic pollution compared to other Indian lakes as it receive discharges from six rivers; a number of sewage canals and run-off.

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Earthworms encompass significant soil faunal biomass and have tremendous potential to provide vital ecosystem services. Earthworms are considered bioindicators of chemical contaminants and can provide early warnings of ecosystem deterioration. Studies pertaining to the accumulation of pesticide residues in earthworm in biomass in agrarian ecosystems are scarce.

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  • Excited-state chemistry emphasizes the importance of molecular communication, especially when assessing how confinement affects this interaction.
  • The study focused on the behavior of the molecule 4'-diethylaminoflavonol (DEA3HF) in both confined mediums (octa acid) and ethanolic solutions in the presence of Rhodamine 6G (R6G).
  • Despite the expected interactions indicated by spectral overlap and fluorescence quenching, results showed a constant fluorescence lifetime, suggesting a static quenching mechanism rather than FRET, and an emissive complex formation between DEA3HF and R6G was confirmed.
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  • Recent research has focused on octahedral complexes of Ru(II) and Os(II) with bidentate polypyridyl ligands, highlighting their potential in cancer treatment and their existence as enantiomers.
  • The study successfully adapted Cyclofructan-6 (CF6) with (R)-naphthyl ethyl (RN) groups for SFC, achieving the first chiral separation of 23 different ionic complexes, revealing unique interactions and enantioselectivity influenced by the
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A family of complexes of the type [Ru(tpbn)(IP-R)(4-pic)]Cl (tbpn=2,2'-(4-(-butyl)pyridine-2,6-diyl)bis(1,8-napthyridine); 4-pic=4-picoline; IP-R=imidazo[4,5-][1,10]phenanthroline attached to an aromatic group R for - and H for ) were prepared as near-infrared (NIR) absorbing coordination complexes to test whether triplet intraligand excited states (IL) of higher energy than the lowest-lying triplet metal-to-ligand charge transfer excited states (MLCT) could effectively generate cytotoxic singlet oxygen (O) and elicit in vitro photodynamic therapy (PDT) effects. Aromatic groups ranged from benzene to anthracene, with corresponding triplet state energies that were all significantly higher (approximately 3.7-1.

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Tumor hypoxia renders treatments ineffective that are directly (e.g., radiotherapy and photodynamic therapy) or indirectly (e.

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  • The degradation of larger plastic debris into microplastics (MPs), which are less than 5 mm in size, has been driven by natural factors like wind, waves, UV exposure, and biological action, leading to their wide presence in marine environments, including the Arctic Ocean.
  • Research on MPs has focused more on water columns and marine life rather than sediment, making studies on sedimentary MPs in Arctic regions, particularly Kongsfjorden, less common.
  • In Kongsfjorden, sediment analysis showed MPs present at three sampling sites, with a maximum of 24 MPs/kg, predominantly consisting of high-density polyethylene (HDPE), indicating a need for further study to determine their sources and environmental impacts.
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  • * Research has historically focused on optimizing the design of photosensitizers (PSs) to improve their efficiency in generating singlet oxygen, with advancements made by considering their structure and energy states.
  • * This review discusses the innovative supramolecular approach that enhances the effectiveness of less active PSs by utilizing non-bonding interactions, aiming to guide future research and harness the untapped potential of singlet oxygen generation.
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Estimating the fractional distribution of sediment-bound heavy metals is highly significant for its ecological risk assessment in contaminated aquatic systems, since environmental factors enhance the mobility of heavy metals and its accumulation in different ecological matrices. In this study, the fractional distribution of Zn, Cd, Pb and Cu in the sediments of the Cochin estuary, along the south-west coast of India, was estimated along with its accumulation in four edible crustaceans. The high mobility of heavy metals in the Cochin estuary was evident from the distribution in fractions other than residual fraction.

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In an earlier study of π-expansive ruthenium complexes for photodynamic and photochemo-therapies, it was shown that a pair of structural isomers differing only in the connection point of a naphthalene residue exhibited vastly different biological activity. These isomers are further explored in this paper through the activity of their functionalized derivatives. In normoxia, the inactive 2-NIP isomer (5) can be made as photocytotoxic as the active 1-NIP isomer (1) by functionalizing with methyl or methoxy groups, while methoxy variants of the 1-NIP isomer became inactive.

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Article Synopsis
  • - The study explores a catalytic pathway for turning water into oxygen using dinuclear transition metal complexes, particularly with two Ru centers at different separations.
  • - Two new symmetrical bis-tridentate polypyridine ligands were designed, resulting in one catalyst with closely spaced Ru centers being more effective in water oxidation when reacting with Ce at pH 1.
  • - The research highlights a bridging ligand that breaks down under Ce's influence to create catalyst fragments, while also noting a second less reactive catalyst due to its structural stability and warnings about using Ce due to possible catalyst decay.
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Ticks are important vectors that transmit several pathogens including human anaplasmosis agent, Anaplasma phagocytophilum. This bacterium is an obligate intracellular rickettsial pathogen. An infected reservoir animal host is often required for maintenance of this bacterial colony and as a source for blood to perform needle inoculations in naïve animals for tick feeding studies.

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Single crystalline perovskite solar cells (PSC) are promising for their inherent stability due to the absence of grain boundaries. While the development of single crystals of perovskite with enhanced optoelectronic properties is known, studies on the growth, device performance and understanding of the intrinsic stability of single crystalline perovskite thin film solar cell devices fabricated on electron selective contacts are scarcely explored. In this work, we examine the impact of mesoporous TiO (m-TiO) and planar TiO (p-TiO) on the growth of single crystalline-methyl ammonium lead iodide (SC-MAPbI) film, PSC device performance and film stability under harsh weather conditions (T ∼ 85 °C and RH ∼ 85%).

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The microRNAs (miRNAs) are important regulators of gene expression. In this study, we provide evidence for the first time to show that rickettsial pathogen Anaplasma phagocytophilum infection results in the down-regulation of tick microRNA-133 (miR-133), to induce Ixodes scapularis organic anion transporting polypeptide (isoatp4056) gene expression critical for this bacterial survival in the vector and for its transmission to the vertebrate host. Transfection studies with recombinant constructs containing transcriptional fusions confirmed binding of miR-133 to isoatp4056 mRNA.

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Trace metal contamination in aquatic ecosystems is of significant concern in countries like India having a recent industrial history. The present study mainly focuses on the spatial and temporal distribution, occurrence and toxicity of five trace metals (Hg, Cd, Zn, Cu and Pb) in water and sediment matrix of Vembanad Lake system (VLS), India. Mercury analysis was done by using Cold Vapor Atomic Fluorescence Spectrometer, and the other metals were analysed using Volta metric-Trace metal analyser.

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Beetles of the subfamily Scolytinae are the most damaging insects in the world. Among which the black twig borer, (Eichhoff) (Coleoptera: Curculionidae: Scolytinae), is one of the serious pests in coffee plantations. Their cryptic life cycle inside the host plant makes these insects difficult to control.

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The lack of an efficient modelling-simulation-analysis workflow for creating and utilising detailed subject-specific computational models is one of the key reasons why simulation-based approaches for analysing socket-stump interaction have not yet been successfully established. Herein, we propose a novel and efficient modelling-simulation-analysis workflow that uses commercial software for generating a detailed subject-specific, three-dimensional finite element model of an entire residual limb from Diffusion Tensor MRI images in <20 min. Moreover, to complete the modelling-simulation-analysis workflow, the generated subject-specific residual limb model is used within an implicit dynamic FE simulation of bipedal stance to predict the potential sites of deep tissue injury.

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The existence of Organochlorine pesticides (OCP's) and trace metals in tropical aquatic environments may cause a severe threat on account of their ubiquitous nature and long persistence. Monitoring of such contaminants has assumed immense significance in recent times. The present study assessed the OCP's and trace metal contamination in the surface sediments of the Vembanad wetland system in India.

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Article Synopsis
  • Silica particles hosting cavitands and organic guest molecules mix and migrate when shaken with water, creating unique capsular complexes.
  • These complexes do not form in either water alone or organic solvents, highlighting the significance of cavitand movement on the silica surface.
  • The guests enclosed in these complexes displayed selective photochemical reactions similar to those observed in traditional organic capsules in solution.
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The role of earthworms in soil carbon dynamics is a recent avenue of research which is less studied in India. Three plots of 1 m size were laid in Jeevaka live laboratory (JLL)- a biodiversity rich area within the University campus. A control plot (CP) of same dimension was maintained outside JLL.

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Contamination of estuarine system due to heavy metals is a severe issue in tropical countries, especially in India. For the evaluation of the risk due to heavy metals, the current study assessed spatial and temporal variation of acid-volatile sulfide (AVS), simultaneously extracted metal (SEM), and total metal concentration as toxicity indicator of aquatic sediments in Vembanad Lake System (VLS), India. Surface sediment samples collected from 12 locations from the northern portion of VLS for 4 years during different seasons.

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Phytoremediation is a promising option for the treatment of municipal solid waste leachate. Combining the leachate pollution index with the phytotoxicity data will be useful in predicting the suitable concentration of leachate for the phytoremediation applications. Understanding the tolerant mechanisms of plants to leachate stress will further help to select the appropriate dose.

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  • The paper discusses the phenomenon of photoinduced electron transfer through an organic molecular wall using octa acid encapsulated ESIPT (Excited State Intramolecular Proton Transfer) dyes as electron donors.
  • The study highlights the effects of encapsulation on the efficiency and dynamics of the electron transfer process, which is significant for potential applications in organic electronics and solar energy conversion.
  • The authors present experimental findings and theoretical analyses that demonstrate how the molecular environment influences electron transfer, contributing to a deeper understanding of energy transfer mechanisms in organic materials.
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  • Researchers found that certain dyes can transfer electrons efficiently when they're enclosed in a water-soluble structure called octa acid in water.
  • The study showed that 4,4′-Dimethylviologen dichloride is the most effective electron acceptor compared to another compound, N-methylpyridinium iodide.
  • This effectiveness is likely due to 4,4′-Dimethylviologen's stronger binding to the outer walls of the host octa acid.
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