Publications by authors named "John Neena"

The formation of NiOOH on the catalyst surface is widely considered to be the active species in electrochemical urea oxidation reactions (UOR). Though in situ-formed NiOOH species are reported to be more active than the synthesized ones, the mechanistic study of the actual active species remains a daunting task due to the possibility of different phases and instability of surface-formed NiOOH. Herein, mechanistic UOR aspects of electrochemically activated metallic NiNb Nanoglass showing stability toward the γ-NiOOH phase are reported, probed via in situ Raman spectroscopy, supported by electron microscopy analysis and X-ray photoelectron spectroscopy in contrast with the β-NiOOH formation favored on Ni foil.

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In early years, SERS-active substrates were generally noble metals. However, their practical applications were limited due to their poor biocompatibility, low uniformity and high cost. Recently, the utilization of semiconductor SERS-active substrates has greatly expanded the applications of SERS in many fields.

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Idiopathic intussusception is the most common form of intussusception in infants and young children. In older children and adults, intussusception being rare, the lead point is usually an underlying bowel pathology (Meckel's diverticulum, hemangioma, carcinoids, polyps, submucous lipomas, etc.) and these are called pathological lead points (PLP's).

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Liquid exfoliation can be considered as a viable approach for the scalable production of 2D materials due to its various benefits, although the polydispersity in the obtained nanosheet size hinders their straightforward incorporation. Size-separation can help alleviate these concerns, however a correlation between nanosheet size and property needs to be established to bring about size-specific applicability. Herein, size-selected aqueous nanosheet dispersions have been obtained via centrifugation-based protocols, and their chemical activity in the spontaneous reduction of chloroplatinic acid is investigated.

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A substrate for surface-enhanced Raman spectroscopy (SERS) in a sandwich configuration, noble metal/analyte/defect-rich metal oxide, is demonstrated for the detection of methylene blue(MB). The sandwich structure (Ag/MB/SUMoO) is fabricated by physical vapour deposition of Ag nanoparticles over the MB analytes that are adsorbed on sea urchin MoO(SUMoO). SUMoOare grown on a glass substrate by chemical bath deposition.

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The Bethesda system for reporting thyroid cytopathology (TBSRTC) has attempted to standardize thyroid fine needle aspiration cytology (FNAC) reporting internationally into six diagnostic categories and help in clinical decision making. But there exists a significant variation in the reporting percentage and rates of malignancies in each category across the centres which complicates clinical decision making. To study the usefulness of TBSRTC in surgical planning of thyroid nodules and to correlate TBSRTC with final histopathology.

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Bariatric surgery is a sustainable weight loss approach, including vertical sleeve gastrectomy (VSG). Obesity exacerbates tumor growth, while diet-induced weight loss impairs progression. It remains unknown how bariatric surgery-induced weight loss impacts cancer progression or alters response to therapy.

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Carbon dots (CDs) have become one of the most emerging materials as an alternative solar light-induced photocatalyst in contrast to traditional metal-based systems. However, one of the major challenges is the lack of visible light absorption. Herein, we have fabricated unique N, P-co-doped CDs with a self-assembled onion-like layered structure by using a bottom-up facile synthesis technique from chitosan gel and phosphoric acid as molecular precursors.

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The influence of single-layer graphene on top of a SiO/Si surface on the orientation of nonplanar lead phthalocyanine (PbPc) molecules is studied using two-dimensional grazing incidence X-ray diffraction. The studies indicate the formation of a mixture of polymorphs, i.e.

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A low cost reduced graphene oxide-copper hybrid nano thin-film modified Pencil Graphite Electrode has been employed to detect the l-tyrosine enantiomer. The free-standing rGO-Cu hybrid nano-thin film was prepared by a simple one-step liquid-liquid interface method. Electrochemical Cyclic Voltammetry, Differential Pulse Voltammetry, pH-dependent and scan rate dependent studies on bare PGE, Cu, rGO, and rGO-Cu for l-tyrosine have been explained in detail.

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The rapid, ultralow detection, degradation, and complete removal of pesticides demand the design of potential substrates. Herein, we discussed gold nanorods (Au NRs) as the potential substrate for the naked eye detection and degradation of two common and broad-spectrum pesticides, chlorpyrifos (CPF) and malathion (MLT), up to 0.15 ppt concentration within 2 min.

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The structural organization and its effect on conducting pathways in lead phthalocyanine (PbPc) thin films, a nonplanar phthalocyanine, deposited on Si and highly oriented pyrolytic graphite (HOPG) substrates in the presence of iodine and ammonia vapors are presented. Two-dimensional grazing incidence X-ray diffraction studies reveal that the crystalline ordering in pristine PbPc films on Si and HOPG substrates undergoes a drastic molecular rearrangement and surface reconstruction upon iodine doping. The structural rearrangement leads to morphological changes and higher surface roughness in iodine doped PbPc (I-PbPc) films.

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Tribological studies of the 2D nanoadditives such as MoS and graphene are mostly performed in base oils such as SN500, SN150, or paraffin. We have focused on their effect in lubrication properties of industrial oils (e.g.

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Polymers reinforced with nanofillers, especially graphene in recent times, have continued to attract attention to realize novel materials that are cheap and also have better properties. At a different level, encapsulating liquid crystals (LCs) in polymer networks not only adds mechanical strength, but could also result in device-based refractive index mismatch. Here, we describe a novel strategy combining the best of both these concepts to create graphene-incorporated polymer-stabilized LC (PSLC) devices.

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Enhancing the surface-enhanced Raman scattering (SERS) activity of semiconductor metal oxide nanostructures by controlling the morphology and oxygen vacancies towards trace detection of organics is of significant interest. In this study, MoO with a novel sea urchin morphology is synthesized employing chemical bath deposition and consists of hundreds of ∼15 μm long spikes originating from the core forming 20-40 micron globular structures. The spikes taper to form 20 nm sharp tips.

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In situ growth of metallic MoO films on fluorine-doped tin oxide (FTO) and MoO powder in solution was achieved simultaneously by a simple hydrothermal process employing citric acid as the surfactant. The growth mechanism of MoO nanostructures (NSs) at the heterogeneous interface and in homogeneous medium proceeds in a different manner in which seeds grow in a preferred orientation on FTO, whereas they propagate in all directions in solution. The high lattice matching of FTO and MoO favours the film growth which could not be obtained on other conventional substrates.

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Free standing, thin films of reduced graphene oxide (rGO) with ZnO, CuO and SnO(2) nanostructures are prepared at a water/toluene interface utilizing simple interfacial reaction and self-assembly. rGO-ZnO, rGO-CuO and rGO-SnO(2) films exhibit unique morphologies such as hexagonal cylinders, elongated splinters, and balls, respectively, wrapped by rGO layers. The hybrid films exhibit surface enhanced Raman scattering (SERS) of rhodamine 6G dye with enhancement factors one order higher than bare metal oxide caused by a synergic effect of charge transfer between the dye, metal oxide and rGO.

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Background: There is a lack of evidence on barriers faced by persons with disability in accessing employment opportunities in India.

Aim: This study was undertaken to ascertain both employee and employer perceptions on barriers existing among Information Technology (IT) and IT-enabled sectors to employ persons with disabilities.

Materials And Methods: Two hundred participants from six IT/IT-enabled sector organizations were included in the study; study was conducted at Hyderabad, India.

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Article Synopsis
  • Reduced graphene oxide-osmium (rGO-Os) hybrid nano dendrites were created using a straightforward liquid/liquid interface method, resulting in networks of Os nanoparticles on rGO layers.
  • The hybrid film demonstrated improved catalytic activity for reducing -nitroaniline, showing 4.4 s g activity, which is competitive with noble metals like Au and Ag, but less than Pd.
  • Surface-enhanced Raman spectroscopy (SERS) tests indicated that the rGO-Os hybrid film had a significant enhancement factor for detecting dyes, highlighting its potential in electrocatalysis and biomolecule detection.
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No treatments exist to slow or halt Parkinson's disease (PD) progression; however, inhibition of leucine-rich repeat kinase 2 (LRRK2) activity represents one of the most promising therapeutic strategies. Genetic ablation and pharmacological LRRK2 inhibition have demonstrated promise in blocking α-synuclein (α-syn) pathology. However, LRRK2 kinase inhibitors may reduce LRRK2 activity in several tissues and induce systemic phenotypes in the kidney and lung that are undesirable.

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Background: Low folate and vitamin B12 levels have negative effect on pregnancy outcomes but there is paucity of data on their levels among Indian women. Ferritin and haemoglobin are associated with maternal mortality and low birth-weight. Our aim was to estimate the prevalence of deficiency of serum folate and vitamin B12, and low levels of serum ferritin and blood haemoglobin among women of childbearing age from a rural population of South India.

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Aims: Women suffer disproportionately more from cataract blindness compared to males in low- and middle-income countries. Two large population-based surveys have been undertaken in India at an interval of 7 years and data from these surveys provided an opportunity to assess the trends in gender differentials in cataract blindness.

Materials And Methods: Data were extracted from the surveys to discern sex differences in cataract blindness.

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Background: Hyperuricemia is implicated in cardiovascular and cerebrovascular diseases. This study evaluated associations between uric acid (UA), cardiovascular health, and neurocognitive function in adolescent and adult survivors of childhood acute lymphoblastic leukemia treated with chemotherapy only.

Methods: 126 adolescent [mean (SD) age 14.

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