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Sodium ion batteries are favored in stationary and large scale power storage due to their low cost and nontoxicity. As the lithium is replaced with sodium due to the cost motive, a cheap processing method is needed to maintain the cell price as low as possible. We report an ultra-fast synthesis method that utilizes the high microwave absorbance of silicon carbide content in rice straw ash. Amorphous/maricite mixtures of sodium iron phosphates-carbon composites (NaFePO4-C) are synthesized, crystallized, and carbon coated using one-step microwave heating. The sodium ion electroactive composites are prepared using different microwave heating durations ranging from 30 to 100 s. High purity inert gases are not needed during synthesis, processing, and even at cell assembly. The materials are characterized by elemental analysis techniques, X-ray diffraction (XRD), scanning/transmission electron microscope (SEM/TEM), and Raman spectroscopy. The electrochemical performance of the synthesized nanocomposites is examined as sodium ion battery cathode and as symmetric supercapacitors. The optimum synthesis time is 60 s for the application as sodium ion batteries and as a supercapacitor. The maximum specific capacity is 108.4 mA h g−1 at 0.2 C in the case of using it as a battery cathode. While the capacitance is 86 F g−1 at 0.5 A g−1 as a supercapacitor. The capacity retention is 92.85% after 40 cycles at 0.2 C as sodium ion battery electrode. For supercapacitor, the capacity retention is 81.7% after 1000 cycles. [ABSTRACT FROM AUTHOR]

Microbial contamination is one of the major dreadful problems that raises hospitalization, morbidity and mortality rates globally, which subsequently obstructs socio-economic progress. The continuous misuse and overutilization of antibiotics participate mainly in the emergence of microbial resistance. To circumvent such a multidrug-resistance phenomenon, well-defined nanocomposite structures have recently been employed. In the current study, a facile, novel and cost-effective approach was applied to synthesize Ag@Ag2O core–shell nanocomposites (NCs) via chemical method. Several techniques were used to determine the structural, morphological, and optical characteristics of the as-prepared NCs. XRD, Raman, FTIR, XPS and SAED analysis revealed a crystalline hybrid structure of Ag core and Ag2O shell. Besides, SEM and HRTEM micrographs depicted spherical nanoparticles with size range of 19–60 nm. Additionally, zeta potential and fluorescence spectra illustrated aggregated nature of Ag@Ag2O NCs by − 5.34 mV with fluorescence emission peak at 498 nm. Ag@Ag2O NCs exhibited higher antimicrobial, antibiofilm, and algicidal activity in dose-dependent behavior. Interestingly, a remarkable mycocidal potency by 50 μg of Ag@Ag2O NCs against Candida albican; implying promising activity against COVID-19 white fungal post-infections. Through assessing cytotoxicity, Ag@Ag2O NCs exhibited higher safety against Vero cells than bulk silver nitrate by more than 100-fold. [ABSTRACT FROM AUTHOR]

Over the past two decades, a number of researchers studied different aspects of the unconnected piled raft foundation (UPRF) system. In this system, a structural fill cushion is inserted between the raft and the concrete piles (PC) where the cushion transfers the loads from the superstructure to the piles. They showed that UPRF could increase the load-bearing share of the raft relative to that of the concrete piles, which leads to a favourable economic impact. Stone columns (SC) and deep-mixed columns (DMC) have also gained substantial popularity in the last few decades, and have shown pronounced success in substituting concrete pile foundations in numerous projects. This paper is an attempt to explore the viability of using SC and DMC in the UPRF system. Different column parameters such as material, stiffness, spacing, embedment length, configuration and raft thickness may affect the design considerations of UPRF systems. The current study investigates the effect of such parameters on the performance of the UPRF. In addition, two cushion alternatives were also studied: structural fill and EPS Geofoam. 3D finite element models of a 16-storey building on soft clay were used to compare the behaviour of different types of UPRF foundations embedded in different types of soft clays. A coupled hydraulic and mechanical model using the Modified Cam Clay soil model was used to model the soft soil. [ABSTRACT FROM AUTHOR]

The bio-imaging technology is one of the most significant modern applications used in several fields, including early diagnosis of many illnesses that are most important diseases facing humanity and other vital uses. The primary advancement in nanotechnology is the creation of innovative fluorescence probes called quantum dots (QDs). The use of molecular tagging in research, in vivo, and in vitro studies is revolutionized by quantum dots. The application of QD indicates conversion in natural imaging and photography has demonstrated extraordinary appropriateness in bio-imaging, the discovery of novel drugs, and delivery of targeted genes, biosensing, photodynamic therapy, and diagnosis. New potential methods of early cancer detection and treatment management are being researched as a result of the special physical and chemical characteristics of QD probes. The bio-imaging technique depends on the fluorescent emission of the used materials, which is paired with living cells that are easy to see it in 3D without any surgical intervention. Therefore, the use of QDs many types that have unique and appropriate properties for use in that application; In terms of fluorescent emission strength, duration and luminosity.This review article displays some methods of preparation for QDs nanomaterials and the devices used in this. In addition, it presentssome of challenges that must be avoided for the possibility of using them in the bio-imaging field; as toxicity, bio-compatibility, and hydrophilization. It’s reviewed some of the devices that use QDs in bio-imaging technique, the QDs application in cell analysis-imaging, and QDs application in vivo imaging. [ABSTRACT FROM AUTHOR]

Objective To evaluate the accuracy of CESM technique in predicting the final pathological response and residual tumor size post NAC in LABC. Patients and methods This study was prospectively carried on 21 female patients diagnosed with stage II and III breast cancer. CESM was done at the end of last cycle of chemotherapy and before definitive surgery. Results The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), false negative and false positive of the CESM were assessed by comparing the enhancement of the residual lesions and their size post neoadjuvant chemotherapy (NAC) with the final pathological response and residual tumor size in the MD Anderson system. The specificity of the CESM in predicting the tumor response to NAC in this initial study is 91%, sensitivity was 40% and the NPV and PPV were 80% and 62.5% respectively. The sensitivity of this technique for complete response detection was 100% with a specificity 83% and lowered sensitivity in detecting chemoresistant tumors (33.3%). Conclusion CESM is an emerging easy technique that can predict the final pathologic tumor response after NAC especially complete response acting as a good negative technique. [ABSTRACT FROM AUTHOR]