Publications by authors named "Amrita Pal"

Understanding how per- and polyfluoroalkyl substances (PFASs) enter aquatic ecosystems is challenging due to the complex interplay of physical, chemical, and biological processes, as well as the influence of hydraulic and hydrological factors and pollution sources at the catchment scale. The spatiotemporal dynamics of PFASs across various media remain largely unknown. Here we show the fate and transport mechanisms of PFASs by integrating monitoring data from an estuarine reservoir in Singapore into a detailed 3D model.

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Removal of organic dyes like methylene blue (MB) from industrial effluents serves as potential source of potable water. Photocatalytic degradation using sustainable catalyst is deemed to be an affordable solution. In this work, NdO/MgO nanocomposite with different compositions (1, 3, and 5wt% NdO with MgO) have been achieved using hydrothermal synthesis and characterized extensively.

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Endovascular embolization (EE) has been used for the treatment of blood vessel abnormalities, including aneurysms, AVMs, tumors, etc. The aim of this process is to occlude the affected vessel using biocompatible embolic agents. Two types of embolic agents, solid and liquid, are used for endovascular embolization.

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Women who experienced childhood sexual abuse have higher rates of obesity, a risk factor for obstructive sleep apnea (OSA). We assessed if prior childhood sexual abuse was more common in women with OSA vs. control, with possible mediation by obesity.

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Introduction: Obstructive sleep apnea (OSA) increases sympathetic vasoconstrictor drive and reduces baroreflex sensitivity (BRS), the degree to which blood pressure changes modify cardiac output. Whether nighttime continuous positive airway pressure (CPAP) corrects BRS in the awake state in OSA remains unclear. We assessed spontaneous BRS using non-invasive continuous BP and ECG recordings at rest and during handgrip and Valsalva challenges, maneuvers that increase vasoconstrictor drive with progressively higher BP, in untreated OSA (unOSA), CPAP-treated OSA (cpOSA) and healthy (CON) participants.

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Endovascular embolization of cerebral aneurysms is a common approach for reducing the risk of often-fatal hemorrhage. However, currently available materials used to occlude these aneurysms provide incomplete filling (coils) or require a complicated, time-consuming delivery procedure (solvent-exchange precipitating polymers). The objective of this work was to develop an easily deliverable in situ forming hydrogel that can occlude the entire volume of an aneurysm.

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The current study was focused to evaluate the antioxidant and the anti-cancerous properties of was chosen due to its existing medicinal values. Antioxidant assays like Superoxide radical scavenging assay, Nitrous Oxide radical scavenging assay, were performed, on the methanolic and ethyl acetate extracts of the plant, that depicts the pro-oxidant nature of the extract. Further, they were tested to check cell viability on B cell Acute Lymphoblastic Leukemia (ALL) Cell line (NALM 6), human lung cancer cell line (A549), T cell Acute Lymphoblastic Leukemia cell line (MOLT4), and PBMC isolated from normal donors utilizing MTT assay.

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Study Objectives: Obstructive sleep apnea (OSA) is defined by pauses in breathing during sleep, but daytime breathing dysregulation may also be present. Sleep may unmask breathing instability in OSA that is usually masked by behavioral influences during wakefulness. A breath-hold (BH) challenge has been used to demonstrate breathing instability.

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People with obstructive sleep apnea (OSA) often have psychological symptoms including depression and anxiety, which are commonly treated with anti-depression or anti-anxiety interventions. Psychological stress is a related symptom with different intervention targets that may also improve mental state, but this symptom is not well characterized in OSA. We therefore aimed to describe stress in relation to other psychological symptoms.

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Study Objectives: Brain regulation of autonomic function in obstructive sleep apnea (OSA) is disrupted in a sex-specific manner, including in the insula, which may contribute to several comorbidities. The insular gyri have anatomically distinct functions with respect to autonomic nervous system regulation; yet, OSA exerts little effect on the organization of insular gyral responses to sympathetic components of an autonomic challenge, the Valsalva. We further assessed neural responses of insular gyri in people with OSA to a static handgrip task, which principally involves parasympathetic withdrawal.

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In perinatally HIV-infected (PHIV) children, neurodevelopment occurs in the presence of HIV-infection, and even with combination antiretroviral therapy (cART) the brain can be a reservoir for latent HIV. Consequently, patients often demonstrate long-term cognitive deficits and developmental delay, which may be reflected in altered functional brain activity. Our objective was to examine brain function in PHIV on cART by quantifying the amplitude of low frequency fluctuations (ALFF) and regional homogeneity (ReHo).

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Study Objectives: Cardiovascular comorbidities in obstructive sleep apnea (OSA) are difficult to treat, perhaps due to autonomic dysfunction. We assessed beat-to-beat blood pressure (BP) variability (BPV) in OSA while considering other markers derived from electrocardiogram and continuous BP signals.

Methods: We studied 66 participants (33 participants with OSA: respiratory event index [mean ± SEM]: 21.

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Study Objectives: Obstructive sleep apnea (OSA) patients show impaired autonomic regulation, perhaps related to functional reorganization of the insula, which in healthy individuals shows sex-specific anterior and right dominance during sympathetic activation. We examined insular organization of responses to a Valsalva maneuver in OSA with functional magnetic resonance imaging (fMRI).

Methods: We studied 43 newly diagnosed OSA (age mean ± SD: 46.

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Injectable hydrogels provide a powerful and non-invasive approach for numerous applications in cell transplantation, growth factor delivery, tissue regeneration and so forth. The properties of injectable hydrogels should be well-tuned for specific applications, where their overall design should ensure biocompatibility, non-toxicity, robust mechanical properties, and most importantly the ability to promote vascularization and integration with the host tissue/organ. Among these criteria, vascularization remains a key design element in the development of functional therapeutic hydrogels for successful translation into clinical settings.

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High efficiency perovskite solar cells have underpinned the rapid growth of the field. However, their low device stability limits further advancement. Hygroscopic lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and metal electrode are the main causes of the device instability.

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Development of an ex vivo culture system to expand satellite cells, the resident muscle stem cell population, will be necessary for the development of their use as therapeutics. The loss of the niche environment is often cited as the reason that culture results in both the loss of myogenic potential and low re-engraftment rates of these cells. Studies have shown that culture of satellite cells on more elastic substrates maintained their quiescence and potential and increased re-engraftment, but there was limited proliferation.

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Blood based biomaterials are widely researched and used in different biomedical applications including cell therapy, drug delivery, sealants etc. due to their biocompatibility and biodegradability. Blood derived gels are successfully used in clinical studies due to the presence of fibrinogen and several platelet growth factors.

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We study the effect of organic cation-centered states in mixed organic-inorganic halide perovskites on the bandstructure and optical properties. Clusters of methylammonium lead iodide (MAPbI) and bromide (MAPbBr) and of MAPbI (MAPbBr) in which an organic cation was substituted with formamidinium (FA) and guanidinium (GA) are studied with density functional theory and time-dependent density functional theory. This model permitted comparing bandstructure and optical properties with different organic cations computed with GGA and hybrid functionals.

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Fullerenes have attracted considerable interest as an electron-transporting layer in perovskite solar cells. Fullerene-based perovskite solar cells produce no hysteresis and do not require high-temperature annealing. However, high power conversion efficiency has been only achieved when the fullerene layer is thermally evaporated, which is an expensive process.

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We compare the performance of an approach using real frequency dependent polarizability to compute optical absorption spectra to linear-response time-dependent density functional theory (TD-DFT) for small organic dyes, oligomers of different lengths (oligothiophenes), and molecular clusters representing a molecular crystal (pentacene). For pentacene, the spectra computed with the two methods are also compared to the spectrum computed for clusters and the periodic solid using the dipole approximation. The approach based on real polarizability produces spectra in good agreement with TD-DFT for small molecules.

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The aim of therapeutic neovascularization is to repair ischemic tissues via formation of new blood vessels by delivery of angiogenic growth factors, stem cells or expansion of pre-existing cells. For efficient neovascularization, controlled release of growth factors is particularly necessary since bolus injection of molecules generally lead to a poor outcome due to inadequate retention within the injured site. In this regard, injectable hydrogels, made of natural, synthetic or hybrid biomaterials, have become a promising solution for efficient delivery of angiogenic factors or stem and progenitor cells for tissue repair, regeneration and neovascularization.

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C60 and C60 based molecules are efficient acceptors and electron transport layers for planar perovskite solar cells. While properties of these molecules are well studied by ab initio methods, those of solid C60, specifically its optical absorption properties, are not. We present a combined density functional theory-Density Functional Tight Binding (DFTB) study of the effect of solid state packing on the band structure and optical absorption of C60.

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Animal tissue has an extended history of clinical use in applications like heart valve bioprosthesis devices, cardiovascular surgical applications etc. but often does not last long after implantation in the body due to rapid unwanted degradation. The goal of this work is to develop novel composite biomaterials by grafting biological tissue with synthetic, biodegradable polymers.

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We present a systematic comparative density functional theory-density functional tight binding study of multiple derivatives of C60 and C70 with different addends, in molecular as well as solid state. In particular, effects due to fullerene size, type and number of addends, and of crystallinity on band structure, charge transport, and optical properties are investigated. These are important, in particular, for rational selection of fullerene derivatives as acceptor and electron transport layers in organic as well as planar inverted perovskite solar cells.

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Aim: The purpose of this study was to examine the prevalence of dental caries in primary dentition of 5-6-year-old children in urban and rural areas of Jabalpur city.

Materials And Methods: The present cross-sectional study was conducted in the rural and urban areas of Jabalpur city, India. A power analysis was carried out to select a representative sample of 5-6-year-old children ( = 408), 204 from government schools and 204 from private schools.

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