Graphene quantum dots (GQDs) from organic acids

An environmentally eco-friendly method of synthesis of graphene quantum dots (GQDs) was reported using pyrolysis of organic acids, viz., tartaric acid and ascorbic acid at 150-160 °C, which produce (GQDs) in the presence of NaOH. The heating time and effect of different pH on the formation of GQDs have been studied in detail to optimize the reaction conditions. The UV-visible absorption and normalized fluorescence spectra have been applied to analyze the optical and luminescent properties of GQDs. The particles size distribution of the GQDs obtained from different organic acids at different pH has been also determined. The microstructures and surface morphology have been studied by atomic force microscope (AFM)

N- Graphene Derivatives from Papaya Seeds: Synthesis and Chemistry

246-249A two-step synthesis of nitrogen containing graphene (N-graphene) from papaya seeds is reported here. The preparation of N-graphene from a non-graphitic nitrogen containing precursor, without doping is really a challenging task. However, when papaya seeds were pyrolyzed at 250 oC temperature for 2 hrs, it led to the formation of N-GO without any additional oxidizing agent. Further, N-GO was converted to Nr-GO in presence of thiourea as a reducing agent. The synthesized N-GO was found to remove 82 % of iron from ground water

Non-toxic fabrication of fluorescent carbon nanoparticles from medicinal plants/sources with their antioxidant assay

This research work showcases a non-toxic approach to synthesize carbon nanoparticles (CNPs) from various medicinal plants namely Syzygium cumini, Holy basil, Azadirachta indica A, Psidium guajava, Mangifera indica, and Bergera koenigii using microwave approach. The optical, morphological, structural, and functional properties of obtained CNPs from all mentioned sources were investigated using UV-Vis, Scanning electron microscopy (SEM), Fourier transform infrared spectrophotometry (FTIR), dynamic light scattering (DLS), zeta potential tests and X-ray diffraction (XRD). With great water dispersibility, and photostability all the medicinal sources chosen yielded in bright red fluorescent nanoparticles under exposure to UV light, thereby giving a significant peak around 650 nm recorded in absorption spectrum. Antoxidant assay was performed on all these six different plant-derived nanoparticles with two different concentrations and all have exhibited excellent free radical (DPPH) scavenging activity, proving their role as antioxidants. This further opens up doors for various other plant and biomedical applications to be targeted using these CNPs.Comment: 13 pages, 7 figure

N- Graphene Derivatives from Papaya Seeds: Synthesis and Chemistry

A two-step synthesis of nitrogen containing graphene (N-graphene) from papaya seeds is reported here. The preparation of N-graphene from a non-graphitic nitrogen containing precursor, without doping is really a challenging task. However, when papaya seeds were pyrolyzed at 250 oC temperature for 2 hrs, it led to the formation of N-GO without any additional oxidizing agent. Further, N-GO was converted to Nr-GO in presence of thiourea as a reducing agent. The synthesized N-GO was found to remove 82 % of iron from ground water

Lysosomal drug sequestration as a mechanism of drug resistance in vascular sarcoma cells marked by high CSF-1R expression

Human angiosarcoma and canine hemangiosarcoma are thought to arise from vascular tissue or vascular forming cells based upon their histological appearance. However, recent evidence indicates a hematopoietic or angioblastic cell of origin for these tumors. In support of this idea, we previously identified an endothelial-myeloid progenitor cell population with high expression of endothelial cell markers and the myeloid cell marker, colony stimulating factor 1 receptor (CSF-1R). Here, we further characterized these cells to better understand how their cellular characteristics may impact current therapeutic applications. We performed cell enrichment studies from canine hemangiosarcoma and human angiosarcoma cell lines to generate cell populations with high or low CSF-1R expression. We then utilized flow cytometry, side population and cell viability assays, and fluorescence based approaches to elucidate drug resistance mechanisms and to determine the expression of hematopoietic and endothelial progenitor cell markers. We demonstrated that cells with high CSF-1R expression enriched from hemangiosarcoma and angiosarcoma cell lines are more drug resistant than cells with little or no CSF-1R expression. We determined that the increased drug resistance may be due to increased ABC transporter expression in hemangiosarcoma and increased drug sequestration within cellular lysosomes in both hemangiosarcoma and angiosarcoma. We identified drug sequestration within cellular lysosomes as a shared drug resistance mechanism in human and canine vascular sarcomas marked by high CSF-1R expression. Taken together, our results demonstrate that studies in highly prevalent canine hemangiosarcoma may be especially relevant to understanding and addressing drug resistance mechanisms in both the canine and human forms of this disease

Propranolol Sensitizes Vascular Sarcoma Cells to Doxorubicin by Altering Lysosomal Drug Sequestration and Drug Efflux

Angiosarcoma is a rare cancer of blood vessel–forming cells with a high patient mortality and few treatment options. Although chemotherapy often produces initial clinical responses, outcomes remain poor, largely due to the development of drug resistance. We previously identified a subset of doxorubicin-resistant cells in human angiosarcoma and canine hemangiosarcoma cell lines that exhibit high lysosomal accumulation of doxorubicin. Hydrophobic, weak base chemotherapeutics, like doxorubicin, are known to sequester within lysosomes, promoting resistance by limiting drug accessibility to cellular targets. Drug synergy between the beta adrenergic receptor (β-AR) antagonist, propranolol, and multiple chemotherapeutics has been documented in vitro, and clinical data have corroborated the increased therapeutic potential of propranolol with chemotherapy in angiosarcoma patients. Because propranolol is also a weak base and accumulates in lysosomes, we sought to determine whether propranolol enhanced doxorubicin cytotoxicity via antagonism of β-ARs or by preventing the lysosomal accumulation of doxorubicin. β-AR-like immunoreactivities were confirmed in primary tumor tissues and cell lines; receptor function was verified by monitoring downstream signaling pathways of β-ARs in response to receptor agonists and antagonists. Mechanistically, propranolol increased cytoplasmic doxorubicin concentrations in sarcoma cells by decreasing the lysosomal accumulation and cellular efflux of this chemotherapeutic agent. Equivalent concentrations of the receptor-active S-(−) and -inactive R-(+) enantiomers of propranolol produced similar effects, supporting a β-AR-independent mechanism. Long-term exposure of hemangiosarcoma cells to propranolol expanded both lysosomal size and number, yet cells remained sensitive to doxorubicin in the presence of propranolol. In contrast, removal of propranolol increased cellular resistance to doxorubicin, underscoring lysosomal doxorubicin sequestration as a key mechanism of resistance. Our results support the repurposing of the R-(+) enantiomer of propranolol with weak base chemotherapeutics to increase cytotoxicity and reduce the development of drug-resistant cell populations without the cardiovascular and other side effects associated with antagonism of β-ARs

Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe

COMPARATIVE STUDY OF TRAINING EFFECTIVENESS MEASUREMENT MODELS

In the global, competitive digital environment it is crucial that an organization should set its objectives for the continual improvement. Organizations focused toward growth and development adopts a strategic and planned approach for the maintenance of human resource. Training is an indispensable way to keep organization competitive. Initiative taken and positive efforts produce improvement in the quality of manpower, which in turn is one of the most contributors to national economic growth. To improve organization’s effectiveness training is the focal point. In order to implement right training methods, organization should be aware of the training methods and their effectiveness. Study explores the measurement methods of training evaluation which is very crucial for the training effectiveness. This study tries to give general overview of training effectiveness measurement models with critical appreciation

Graphene quantum dots (GQDs) from organic acids

128-134An environmentally eco-friendly method of synthesis of graphene quantum dots (GQDs) was reported using pyrolysis of organic acids, viz., tartaric acid and ascorbic acid at 150-160 °C, which produce (GQDs) in the presence of NaOH. The heating time and effect of different pH on the formation of GQDs have been studied in detail to optimize the reaction conditions. The UV-visible absorption and normalized fluorescence spectra have been applied to analyze the optical and luminescent properties of GQDs. The particles size distribution of the GQDs obtained from different organic acids at different pH has been also determined. The microstructures and surface morphology have been studied by atomic force microscope (AFM)