6 research outputs found

    Synthesis, Mesomorphic and Molar Conductivity Studies of some Macrocyclic Phthalocyanine Palladium (II)

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    Two series of Macrocyclic Phthalocyanine Palladium(II) namely 4,4,4,4-RnPcPd and 3,3,3,3-RnPcPd were prepared and characterized. The mesomorphic investigation by hot stage polarizing microscope for these series was carried out. This investigation revealed that the 4,4,4,4-RnPcPd series exhibited columner mesophases while the second series 3,3,3,3-RnPcPd did not show any liquid crystalline properties.The molar conductivity measurments carried out in dimethyl sulfoxide and N,N-dimethyl formamide solvents for all prepared compounds at room temperature indicate that these compounds behave as weak electrolytes . Keywords: Macrocyclic compounds, Macrocyclic complexes, Liquid Crystals, Conductivity

    Synthesis and Thermal Characterization of Copolymers Containing Amino Acids

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    Thee copolymers of amino acid were synthesized in two steps. First, the amino acids react with resorcinol to formation of azo monomers step. They led in a second condensation polymerization step to copolymeric materials. The structures of the copolymers were characterized by means of FT-IR and 1H-NMR spectroscopy. The thermal properties were investigated by TGA and DTG. Keywords: copolymers, amino acid, thermal properties, azo compoun

    Asymmetrical liquid crystals synthesis for effective sensing: Fluorescence investigations

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    Currently, a new set of asymmetrical dimeric molecules with a Schiff-base at one end and a chalcone alkali substitution by di-ether are made and their liquid crystal and fluorescence properties are investigated. The proposed chemical structure was confirmed by routine analytical methods using FT-IR and NMR spectroscopy. Additionally, polarized optical microscopy (POM); was used to assess the pointed compounds' liquid crystalline characteristics, while differential scanning calorimetry (DSC); was employed to confirm the compounds' transitions. The results report the length of the alkali chain at one end of the molecule is critical to the creation of the mesophase type. Compounds with medium-length chains exhibit nematic mesophases with moderate transition temperatures. The fluorescence of compounds was analyzed, with blue-emitting results indicating the presence of blue-light-emitting features. The 10a had higher ɛ; as well as red-shifted λmax; and Fmax; compared to the others and has blue light emission properties. Eventually; the expanding range of possible uses to include OLED material and fluorescent probes for sensing applications

    Impact of the COVID-19 pandemic on patients with paediatric cancer in low-income, middle-income and high-income countries: a multicentre, international, observational cohort study

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    OBJECTIVES: Paediatric cancer is a leading cause of death for children. Children in low-income and middle-income countries (LMICs) were four times more likely to die than children in high-income countries (HICs). This study aimed to test the hypothesis that the COVID-19 pandemic had affected the delivery of healthcare services worldwide, and exacerbated the disparity in paediatric cancer outcomes between LMICs and HICs. DESIGN: A multicentre, international, collaborative cohort study. SETTING: 91 hospitals and cancer centres in 39 countries providing cancer treatment to paediatric patients between March and December 2020. PARTICIPANTS: Patients were included if they were under the age of 18 years, and newly diagnosed with or undergoing active cancer treatment for Acute lymphoblastic leukaemia, non-Hodgkin's lymphoma, Hodgkin lymphoma, Wilms' tumour, sarcoma, retinoblastoma, gliomas, medulloblastomas or neuroblastomas, in keeping with the WHO Global Initiative for Childhood Cancer. MAIN OUTCOME MEASURE: All-cause mortality at 30 days and 90 days. RESULTS: 1660 patients were recruited. 219 children had changes to their treatment due to the pandemic. Patients in LMICs were primarily affected (n=182/219, 83.1%). Relative to patients with paediatric cancer in HICs, patients with paediatric cancer in LMICs had 12.1 (95% CI 2.93 to 50.3) and 7.9 (95% CI 3.2 to 19.7) times the odds of death at 30 days and 90 days, respectively, after presentation during the COVID-19 pandemic (p<0.001). After adjusting for confounders, patients with paediatric cancer in LMICs had 15.6 (95% CI 3.7 to 65.8) times the odds of death at 30 days (p<0.001). CONCLUSIONS: The COVID-19 pandemic has affected paediatric oncology service provision. It has disproportionately affected patients in LMICs, highlighting and compounding existing disparities in healthcare systems globally that need addressing urgently. However, many patients with paediatric cancer continued to receive their normal standard of care. This speaks to the adaptability and resilience of healthcare systems and healthcare workers globally

    Twelve-month observational study of children with cancer in 41 countries during the COVID-19 pandemic

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    Childhood cancer is a leading cause of death. It is unclear whether the COVID-19 pandemic has impacted childhood cancer mortality. In this study, we aimed to establish all-cause mortality rates for childhood cancers during the COVID-19 pandemic and determine the factors associated with mortality
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