Publications by authors named "Sathishkumar M"

A novel biosynthesis approach was used to develop zinc selenite (ZnSeO) catalysts from the plant extracts of Nephrolepis cordifolia (ZnSeO:NC) and Ziziphus jujube (ZnSeO:ZJ) using hydrothermal method. This study investigates the structural, morphological, and optical properties of pure and biosynthesized ZnSeO catalysts. X-ray diffraction (XRD) analysis confirms the presence of an orthorhombic phase in both catalyst types.

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The main aim of this work is to enhance the wear performance of the direct metal laser sintered (DMLS) alloy 718 by solution treatment aging (STA) method at room temperature (RT) (28°C) and 400°C in dry sliding conditions. The effect of microstructure, phase analysis, and microhardness on the wear behavior and the influence of STA on the specimen at elevated temperatures were studied. The microstructure revealed the presence of melt pool boundary (MPB) in untreated DMLS alloy while recrystallized grains were observed in the STA-treated alloy.

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Basalt-based natural fiber hybrid composites with fillers are always the most anticipated composite material candidates for lightweight structural applications. Current work focusses on the preparation, characterization and testing of Basalt (B)/Hibiscus vitifolius (HV) based epoxy biocomposites with and without cashew nutshell fillers. Individual fiber reinforced composites (with 40 vol% of fibers) and hybrid composites (with 40 vol% of fibers in the ratio 1:1) filled with 10-30 vol% of fillers were manufactured using compression moulding techniques.

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The creation of new alloys with improved qualities has become essential in modern industries for high-performance materials. This work's main objective is to use vacuum arc melting (VAM) to synthesize two different high-entropy alloys (HEAs): AlCrFeNiCu and AlCrFeNiCo. The mechanical properties, phase composition, grain boundaries, and alloy composition of the HEAs were studied.

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This study focuses on the event-triggered control approach for the mathematical model describing the interaction between the sugarcane borer (Diatraea saccharalis) and its egg parasitoid Trichogramma galloi, as well as the combined interaction of Trichogramma galloi and Cotesia flavipes. By employing digital control design, an effective strategy can be devised to minimize the population of natural enemies. Therefore, proposing an event-triggered control mechanism for the sugarcane borer is essential.

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Adults with Down syndrome are less likely to have hypertension than neurotypical adults. However, whether blood pressure measures are associated with brain health and clinical outcomes in this population has not been studied in detail. Here, we assessed whether pulse pressure is associated with markers of cerebrovascular disease and is linked to a diagnosis of dementia in adults with Down syndrome via structural imaging markers of cerebrovascular disease and atrophy.

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UK Biobank is a large-scale epidemiological resource for investigating prospective correlations between various lifestyle, environmental, and genetic factors with health and disease progression. In addition to individual subject information obtained through surveys and physical examinations, a comprehensive neuroimaging battery consisting of multiple modalities provides imaging-derived phenotypes (IDPs) that can serve as biomarkers in neuroscience research. In this study, we augment the existing set of UK Biobank neuroimaging structural IDPs, obtained from well-established software libraries such as FSL and FreeSurfer, with related measurements acquired through the Advanced Normalization Tools Ecosystem.

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Introduction: Virtually all people with Down syndrome (DS) develop neuropathology associated with Alzheimer's disease (AD). Atrophy of the hippocampus and entorhinal cortex (EC), as well as elevated plasma concentrations of neurofilament light chain (NfL) protein, are markers of neurodegeneration associated with late-onset AD. We hypothesized that hippocampus and EC gray matter loss and increased plasma NfL concentrations are associated with memory in adults with DS.

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Individuals with Down syndrome (DS) are less likely to have hypertension than neurotypical adults. However, whether blood pressure measures are associated with brain health and clinical outcomes in this population has not been studied in detail. Here, we assessed whether pulse pressure is associated with markers of cerebrovascular disease, entorhinal cortical atrophy, and diagnosis of dementia in adults with DS.

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UK Biobank is a large-scale epidemiological resource for investigating prospective correlations between various lifestyle, environmental, and genetic factors with health and disease progression. In addition to individual subject information obtained through surveys and physical examinations, a comprehensive neuroimaging battery consisting of multiple modalities provides imaging-derived phenotypes (IDPs) that can serve as biomarkers in neuroscience research. In this study, we augment the existing set of UK Biobank neuroimaging structural IDPs, obtained from well-established software libraries such as FSL and FreeSurfer, with related measurements acquired through the Advanced Normalization Tools Ecosystem.

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Objective: Cognitive loss in older adults is a growing issue in our society, and there is a need to develop inexpensive, simple, effective in-home treatments. This study was conducted to explore the use of olfactory enrichment at night to improve cognitive ability in healthy older adults.

Methods: Male and female older adults ( = 43), age 60-85, were enrolled in the study and randomly assigned to an Olfactory Enriched or Control group.

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White matter hyperintensities are a marker of small vessel cerebrovascular disease that are strongly related to cognition in older adults. Similarly, medial temporal lobe atrophy is well-documented in aging and Alzheimer's disease and is associated with memory decline. Here, we assessed the relationship between lobar white matter hyperintensities, medial temporal lobe subregional volumes, and hippocampal memory in older adults.

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The perforant path, the white matter bundle connecting the entorhinal cortex (ERC) with the hippocampal formation deteriorates with age-related cognitive decline. Previous investigations using diffusion-weighted MRI to quantify perforant path integrity in-vivo have been limited due to image resolution or have quantified the perforant path using methods susceptible to partial volume effects such as the tensor model and without consideration of its 3-dimensional morphology. In this investigation, we use quantitative-anisotropy informed tractography derived from ultra-high resolution diffusion imaging (ZOOMit) to investigate structural connectivity of the perforant path and other medial temporal lobe (MTL) pathways in older adults (63 to 98 years old, n = 51).

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Mnemonic discrimination, a cognitive process that relies on hippocampal pattern separation, is one of the first memory domains to decline in aging and preclinical Alzheimer's disease. We tested whether functional connectivity (FC) within the entorhinal-hippocampal circuit, measured with high-resolution resting state fMRI, is associated with mnemonic discrimination and amyloid-β (Aβ) pathology in a sample of 64 cognitively normal human older adults (mean age, 71.3 ± 6.

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A child's death is a profound loss for mothers and affects hundreds of thousands of women. Mothers report inconsolable and progressive grief that is distinct from depression and impacts daily emotions and functions. The brain mechanisms responsible for this relatively common and profound mental health problem are unclear, hampering its clinical recognition and care.

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Medial temporal lobe (MTL) atrophy is a core feature of age-related cognitive decline and Alzheimer's disease (AD). While regional volumes and thickness are often used as a proxy for neurodegeneration, they lack the sensitivity to serve as an accurate diagnostic test and indicate advanced neurodegeneration. Here, we used a submillimeter resolution diffusion weighted MRI sequence (ZOOMit) to quantify microstructural properties of hippocampal subfields in older adults (63-98 years old) using tensor derived measures: fractional anisotropy (FA) and mean diffusivity (MD).

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We determined the extent to which obstructive sleep apnea (OSA) is associated with increased cerebrovascular disease and amyloid burden, and the relation of the two processes across clinical Alzheimer's disease (AD) diagnostic groups in adults with Down syndrome (DS). Adults with DS from the Biomarkers of Alzheimer's Disease in Down Syndrome (ADDS) study were included given available research MRI ( = 116; 50 ± 8 years; 42% women) and amyloid PET scans ( = 71; 50 ± 7 years; 39% women) at the time of analysis. Participants were characterized as cognitively stable (CS; 64%), with mild cognitive impairment-DS (MCI-DS; 23%), with possible AD dementia (5%), or with definite AD dementia (8%).

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Cerebrovascular disease is associated with symptoms and pathogenesis of Alzheimer's disease (AD) among adults with Down syndrome (DS). The cause of increased dementia-related cerebrovascular disease in DS is unknown. We explored whether protein markers of neuroinflammation are associated with markers of cerebrovascular disease among adults with DS.

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Background: Major Depressive Disorder, characterized by cognitive affective biases, is a considerable public health challenge. Past work has shown that higher depressive symptoms are associated with augmented memory of negative stimuli. In contrast, anxiety symptoms have been associated with overgeneralization of emotional memories.

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Aim: To identify the profiles and factors associated with progression/regression of ultrasound-derived hepatic steatosis with type 2 diabetes mellitus seen at a tertiary diabetes center in southern India.

Methods: Participants were individuals with type 2 diabetes mellitus with at least two consecutive ultrasound measurements available. Hepatic steatosis was assessed using high-resolution B-mode ultrasonography.

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Article Synopsis
  • Most individuals with Down syndrome typically show signs of Alzheimer's disease by age 40 and develop dementia by age 60.
  • The study investigated how the connectivity within the default mode network (DMN) is affected in cognitively stable adults with Down syndrome, using functional MRI scans.
  • Findings indicated altered connectivity patterns within the DMN, suggesting a potential link to accelerated aging and possible early signs of Alzheimer's in individuals with Down syndrome.
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Background: Oral submucous fibrosis (OSMF) is one of the common potentially malignant disorders prevailing in India. The primary etiological factors include tobacco and arecanut, which contain numerous reactive oxygen species (ROS). ROS attack guanine bases in DNA and form 8-hydroxydeoxyguanosine (8-OHdG), which can be detected in patients who have diseases associated with oxidative stress.

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Objective: Adults with Down syndrome (DS) develop Alzheimer disease (AD) pathology by their 5th decade. Compared with the general population, traditional vascular risks in adults with DS are rare, allowing examination of cerebrovascular disease in this population and insight into its role in AD without the confound of vascular risk factors. We examined in vivo magnetic resonance imaging (MRI)-based biomarkers of cerebrovascular pathology in adults with DS, and determined their cross-sectional relationship with age, beta-amyloid pathology, and mild cognitive impairment or clinical AD diagnostic status.

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The non-fluent/agrammatic variant of primary progressive aphasia (nfvPPA) presents with a gradual decline in grammar and motor speech resulting from selective degeneration of speech-language regions in the brain. There has been considerable progress in identifying treatment approaches to remediate language deficits in other primary progressive aphasia variants; however, interventions for the core deficits in nfvPPA have yet to be systematically investigated. Further, the neural mechanisms that support behavioural restitution in the context of neurodegeneration are not well understood.

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A family of 12 members of Naphthalene-2-ol-indolin-2-one-thiocarbamides (5a-l) with pharmacological potentials of cardiovascular modulator were efficiently synthesized and evaluated. These compounds show inhibitory activity on angiotensin-converting enzyme (ACE), which is a principal constituent of the renin-angiotensin system and causative source for hypertension (HTN) (elevated blood pressure) and congestive heart failure (CHF), a parameter that was tested in this report. Prior to this, to get more insight into the binding mode and inhibition of human ACE C-domain (PDB ID: 2XY9) and N-domain (PDB ID: 3NXQ) compounds 5a-l was docked into the active site of them.

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