In this report we have developed different fabrication parameters to tailor the optical bandgap of graphene oxide (GO) nanosheets to make it operational candidate in electronic industry. Here we performed two ways to reduce the bandgap of GO nanosheets. First, we have optimized the oxidation level of GO by reducing amount of oxidizing agent (i.e. KMnO4) to control the sp2/sp3 hybridization ratio for a series of GO nanosheets samples. We noticed the reduction in primary band edge 3.93–3.2 eV while secondary band edge 2.98–2.2 eV of GO nanosheets as the amount of KMnO4 is decreased from 100 to 30%. Second, we have fabricated a series of 2-dimensional nanocomposites sample containing GO/Iron-oxide by using a novel synthesis process wet impregnation method. XRD analysis of synthesized nanocomposites confirmed the presence of both phases,$$\alpha$$ α -Fe2O3 and Fe3O4 of iron-oxide with prominent plane (001) of GO. Morphological investigation rules out all the possibilities of agglomerations of iron oxide nanoparticles and coagulation of GO nanosheets. Elemental mapping endorsed the homogeneous distribution of iron oxide nanoparticles throughout the GO nanosheets. Raman spectroscopy confirmed the fairly constant ID/IG ratio and FWHM of D and G peaks, thus proving the fact that the synthesis process of nanocomposites has no effect on the degree of oxidation of GO flakes. Red shift in G peak position of all the nanocomposites samples showed the electronic interaction among the constituents of the nanocomposite. Linear decrease in the intensity of PL (Photoluminescence) spectra with the increasing of Iron oxide nanoparticles points towards the increased interaction among the iron oxide nanoparticles and GO flakes. Optical absorption spectroscopy reveals the linear decrease in primary edge of bandgap from 2.8 to 0.99 eV while secondary edge decrease 3.93–2.2 eV as the loading of $$\alpha$$ α -Fe2O3 nanoparticles is increased from 0 to 5% in GO nanosheets. Among these nanocomposites samples 5%-iron-oxide/95%-GO nanosheet sample may be a good contestant for electronic devices.

Objectives: To determine serum levels of antistreptolysin O titre (ASOT) and C-reactive protein (CRP) and their association with clinical manifestations of Acute rheumatic fever (ARF). Study Design: Descriptive study. Setting: Department of Diagnostic Immunology and Serology, Children’s Hospital and Institute of Child Health, Lahore. Period: Jan 2015 to Jan 2016. Material & Methods: Fifty clinically confirmed patients of ARF were included in this descriptive study. The samples were taken from Children hospital and Institute of child health Lahore after written informed consent. The sampling technique was convenient sampling. Results: Out of 50 enrolled patients, males were 32(64%) and women 18(36%). Only 5(10%) patients had normal ASOT levels, 20(40%) patients were with borderline ASOT, and 25(50%) patients had titres above 200 IU/ml. There was no significant association of ASOT with gender, age and arthralgia with p-value = 0.060, 0.875 and 0.473, respectively. However, a significant association was found in ASOT with carditis and C-reactive protein (p-value = 0.028 and 0.014, respectively). Only 3 (6%) patients had CRP levels below 6mg/l, whereas 43 (86%) patients were with CRP levels above 6. Only 4(8%) patients had borderline value of CRP titer. There was no significant association between C-reactive protein with gender, age and arthralgia (p-value = 0.148, 0.184 and 0.574, respectively). Moreover, there was a significant association between C-reactive protein with carditis and AOST (p-value = 0.020 and 0.014, respectively). Conclusion: ASOT and CRP are important laboratory parameters reflecting undergoing infection (mainly caused by Streptococcus pyogenes A) and inflammation in patients of ARF. Rising levels of ASOT and CRP in ARF patients might be used as an indicator of involvement of heart tissues and therefore can be used to monitor transition of rheumatic carditis into Rheumatic heart disease.

The field of supercapacitors consistently focuses on research and challenges to improve energy efficiency, capacitance, flexibility, and stability. Low-cost laser-induced graphene (LIG) offers a promising alternative to commercially available graphene for next-generation wearable and portable devices, thanks to its remarkable specific surface area, excellent mechanical flexibility, and exceptional electrical properties. We report on the development of LIG-based flexible supercapacitors with optimized geometries, which demonstrate high capacitance and energy density while maintaining flexibility and stability. Three-dimensional porous graphene films were synthesized, and devices with optimized parameters were fabricated and tested. One type of device utilized LIG, while two other types were fabricated on LIG by coating multi-walled carbon nanotubes (MWCNT) at varying concentrations. Characterization techniques, including scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), Raman spectroscopy, and voltammetry, were employed to analyze the fabricated devices. AFM analysis revealed a surface roughness of 2.03 µm for LIG due to laser treatment. SEM images displayed compact, dense, and porous surface morphology. XRD analysis confirmed the presence of graphene and graphene oxide, which was further supported by energy-dispersive X-ray spectroscopy (EDX) data. Raman spectroscopy indicated that the fabricated samples exhibited distinct D and G bands at 1362 cm–1 and 1579 cm–1, respectively. Cyclic voltammetry (CV) results showed that LIG's capacitance, power density, and energy density were 6.09 mF cm–2, 0.199 mW cm–2, and 3.38 µWh cm–2, respectively, at a current density of 0.2 mA cm–2. The LIG-MWCNT coated electrode exhibited a higher energy density of 6.05 µWh cm–2 and an areal-specific capacitance of 51.975 mF cm–2 compared to the LIG-based devices. The fabricated device has potential applications in smart electronics, nanorobotics, microelectromechanical systems (MEMS), and wearable and portable electronics.

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