Publications by authors named "Vishnu S"

A multifunctional rhodamine derivative containing azo-salicylaldehyde (BBS) was designed and synthesized as a colorimetric and fluorescence turn-on probe for the selective detection of copper cations (Cu) and hypochlorite anions (OCl) in aqueous media. In the presence of Cu, the probe BBS exhibited turn-on absorption and fluorescence change at 554 nm and 585 nm, respectively. The binding mechanism of BBS with Cu induces the opening of a spirolactam ring in the rhodamine moiety by the formation of a metal-ligand complex, achieving 10-fold enhancement in fluorescence and quantum yield, along with a binding constant of 1 × 10 M and a detection limit of 2.

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Article Synopsis
  • Species distribution modeling (SDM) is crucial for predicting where species can be found based on their presence/absence and environmental factors, focusing on current and future climate change impacts through 2050 and 2070.
  • Data was collected from diverse sources for species occurrence, resulting in 105 locations, and 19 bioclimatic variables along with elevation data were used for modeling the distribution in the Western Ghats of India and Sri Lanka.
  • Both models effectively highlighted significant habitat loss under future climate scenarios, emphasizing the urgent need for conservation efforts for critically endangered species in the region.
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A fluorescent molecule, pyridine-coupled bis-anthracene (PBA), has been developed for the selective fluorescence turn-on detection of Cu. Interestingly, the ligand PBA also exhibited a red-shifted ratiometric fluorescence response in the presence of water. Thus, a ratiometric water sensor has been utilized as a selective fluorescence turn-on sensor for Cu, achieving a 10-fold enhancement in the fluorescence and quantum yield at 446 nm, with a lower detection limit of 0.

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Quercetin is an important antioxidant with high bioactivity and it has been used as SARS-CoV-2 inhibitor significantly. Quercetin, one of the most abundant flavonoids in nature, has been in the spot of numerous experimental and theoretical studies in the past decade due to its great biological and medicinal importance. But there have been limited instances of employing quercetin and its derivatives as a fluorescent framework for specific detection of various cations and anions in the chemosensing field.

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This article reports the development of a microscopy imaging system that gives feasibility for studying spatio-temporal dynamics of physiological activities of alive biological specimens (over entire volume not only for a particular section, i.e., in 4D).

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Fluorescent and colorimetric chemosensors for selective detection of various biologically important analytes have been widely applied in different areas such as biology, physiology, pharmacology, and environmental sciences. The research area based on fluorescent chemosensors has been in existence for about 150 years with the development of large number of fluorescent chemosensors for selective detection of cations as metal ions, anions, reactive species, neutral molecules and different gases etc. Despite the progress made in this field, several problems and challenges still exist.

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A novel dual-mode viscosity-sensitive and AIE-active fluorescent chemosensor based on the naphthalene coupled pyrene (NCP) moiety was designed and synthesized for the selective detection of OCl and Cu. In non-viscous media, NCP exhibited weak fluorescence; however, with an increase in viscosity using various proportions of glycerol, the fluorescence intensity was enhanced to 461 nm with a 6-fold increase in fluorescence quantum yields, which could be utilized for the quantitative determination of viscosity. Interestingly, NCP exhibited novel AIE characteristics in terms of size and growth in HO-CHCN mixtures with high water contents and different volume percentage of water, which was investigated using fluorescence, DLS study and SEM analysis.

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The solar receiver is a vital component of concentrated solar collectors that absorbs solar radiation and converts it into heat. One of the challenges the research community faces is minimizing heat loss from the receiver at higher temperatures to maximize the thermal performance of parabolic dish collectors and achieve the system's cost-effectiveness. Cavity receivers have a complex design that makes them more challenging to manufacture and entails higher costs for improved thermal performance.

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We present the case of a 75-year-old female in which a pulmonary tumor embolism was detected incidentally on a prostate-specific membrane antigen positron emission tomography-computed tomography restaging scan. This occurred on the background of renal cell carcinoma in remission with pazopanib systemic therapy and a right nephrectomy 4 years prior. An avidity to prostate-specific membrane antigen in the superior lingula of the left upper lobe of the lung coupled with contrast-enhanced computed tomography findings found the lesion to be a tumor thrombus.

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Background: Early diagnosis of atherosclerosis is exigent in patients with known cardiovascular disease (CVD) risk factors. During the initial phases of atherosclerosis, appearance of plaques can be detected by the ultrasonic phased tracking method which measures the arterial wall elasticity. However, reliable and easily available biochemical markers are not evaluated in the diagnosis of early-stage atherosclerosis.

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Parabolic dish collectors (PDC) efficiently produce hot fluids for medium-temperature applications. Thermal energy storage employs phase change material (PCM) due to its high energy storage density. This experimental research proposes a solar receiver for the PDC with a circular flow path surrounded by PCM-filled metallic tubes.

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Owing to the biological significance of various amino acids, developing accurate and cost-effective sensing techniques for the selective detection of amino acids has recently attracted growing interest. This review discusses the recent advancements of chemosensors in the selective detection of only essential amino acids out of a total of twenty amino acids, which have been applied in chemosensing research, and the mechanism of their action. The focus is directed towards the detection of the most important essential amino acids, like leucine, threonine, lysine, histidine, tryptophan and methionine, since isoleucine and valine are yet to be explored in regard to chemosensing.

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Gastric cancer is one of the leading cancers in Southern India. Data regarding the gastric cancers among the Indian population is sparse. Most patients in our country have locally advanced gastric cancers due to delayed presentation.

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With the rapid miniaturization of integrated chips in recent decades, aggressive geometric scaling of transistor dimensions to nanometric scales has become imperative. Recent works have reported the usefulness of 2D transition metal dichalcogenides (TMDs) like MoS in MOSFET fabrication due to their enhanced active surface area, thin body, and non-zero bandgap. However, a systematic study on the effects of geometric scaling down to sub-10-nm nodes on the performance of MoS MOSFETs is lacking.

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Introduction: Ganglioneuroma (GN) is a rare benign tumor of neural crest origin mostly found in the abdomen, but may occasionally present at sites including the cervical, lumbar, or sacral spine. GN of lumbar spine is a rare occurrence.

Case Report: A 52-year-old man presented with GN in the L1 nerve root, who underwent successful resection of the tumor and stabilization of spine using a single posterior approach.

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Delaminating cells undergo complex, precisely regulated changes in cell-cell adhesion, motility, polarity, invasiveness, and other cellular properties. Delamination occurs during development and in pathogenic conditions such as cancer metastasis. We analyzed the requirements for epithelial delamination in Drosophila ovary border cells, which detach from the structured epithelial layer and begin to migrate collectively.

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The spread of COVID-19 caused wide scale disruptions in the educational sector across the globe. Digital education, which involves the use of digital tools, virtual platforms and online learning, is seen as one of the viable alternatives to continue academic activities in such an environment. Higher education institutions have largely switched to this new mode of learning and continue to rely on digital mode in many parts of the world, due to the ongoing pandemic threat.

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As a consequence of swiftly growing populations in the urban areas, larger quantities of solid waste also form rapidly. Since urban local bodies are found to be unable to manage this perilous situation effectively, there is a high probability of risks relative to the environment and public health. A sudden change is indispensable in the existing systems that are developed for the collection, transportation, and disposal of solid waste, which are entangled in turmoil.

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Context: Emergence of coagulase-negative staphylococci as pathogens in ophthalmia neonatorum.

Aims: To analyze the bacteriological spectrum of ophthalmia neonatorum and its associated risk factors.

Settings And Design: Retrospective analysis in a tertiary care hospital in India.

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Pyrexia of unknown origin (PUO) is a common problem in day-to-day practice. FDG PET CT is an established investigation that aids in identifying the cause of PUO. Due to its high sensitivity PET detects an occult hypermetabolic focus in the body where CT helps in anatomical localization, vascularity, enhancement characteristics of the lesion detected on PET.

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Insulin, a highly conserved peptide hormone, links nutrient availability to metabolism and growth in animals. In fed states insulin levels remain high and in animals that are food deprived insulin signalling drops. Here, we report that in Drosophila, feeding elicited by short periods of starvation is dependent on insulin signalling.

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is one of the leading causes of catheter-associated UTIs (CAUTI) in individuals with prolonged urinary catheterization. Since, biofilm assisted antibiotic resistance is reported to complicate the treatment strategies of infections, the present study was aimed to attenuate biofilm and virulence factor production in Linalool is a naturally occurring monoterpene alcohol found in a wide range of flowers and spice plants and has many biological applications. In this study, linalool exhibited concentration dependent anti-biofilm activity against crystalline biofilm of through reduced production of the virulence enzyme urease that raises the urinary pH and drives the formation of crystals (struvite) in the biofilm.

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Article Synopsis
  • The study investigates the environmental impact of increasing use of ZnO particles, focusing on their transfer from algae (Scenedesmus obliquus) to daphnia (Ceriodaphnia dubia).
  • It finds that the toxicity and absorption of ZnO particles depend on their size and concentration, with smaller particles (50 nm) causing greater harm.
  • Daphnia that fed on ZnO-exposed algae showed significant decreases in survival (15-20%) and accumulated Zn, indicating potential biomagnification in the food chain.
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