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Abstract Ecofriendly ionic liquids (ILs) were synthesized through amidation of ricinoleic acid, the main fatty acid in castor oil, followed by a quaternization reaction to solubilize ethanol in IL/diesel blends at different ratios. As a result, stable and highly renewable, low viscous microemulsion biofuels with high oxygen content were prepared. The prepared fuel samples combine the advantages of green ionic liquids and microemulsion properties. The chemical structures of ILs were confirmed with the aid of NMR and FTIR spectroscopy. DLS analysis revealed that the ethanol particles ranged in size from 8 to 18.1 nm in all samples. As ILs ratios decrease in microemulsion from 37 to 69%, the ethanol particle sizes increase from 10 to 25%. Ethanol shows good solubilization in diesel and IL-1 is more effective than IL-2 in ethanol solubilization at low percentages of ethanol due to more oxygen atoms besides three hydroxyl groups. The ternary phase diagram indicated that the microemulsion area in the case of using IL-1 is larger than that of IL-2. The fuel properties of the prepared microemulsions are nearly close to those of neat diesel and fall within the permitted range of ASTM D975. The viscosity and density values at low ratios of ILs are found to be very close to the values of the neat diesel at different temperatures. The prepared samples show a slight decrease in cetane number and heating value compared to diesel. However, they have improved flash points, cloud points, sulfur content, and acid value. The particle sizes were checked every week and the prepared samples showed high stability with the aid of the synthesized ILs. Moreover, the prepared microemulsions stayed in a transparent appearance for more than a year and no phase separation was observed.

Abstract Compared to the other English medium instruction (EMI) issues, assessment has received very scant research attention. A complex issue in EMI assessment relates to the role of English in measuring learning outcomes, and whether or not language should be assessed along with technical content. Combining questionnaire and semi-structured interviewed data, this study explored the English-related assessment practices and beliefs of native-Arabic and non-native-Arabic faculty members teaching EMI scientific majors at eight Saudi universities. Two hundred and forty-nine faculty members completed the questionnaire, whereas 20 faculty members were interviewed. The results showed that the content teachers do not give much weight to language quality when evaluating students’ written or oral performance. Compared to native-Arabic peers, the non-native-Arabic teachers, who intuitively have little or no translanguaging in their instruction, were found to pay slightly more attention to evaluating students’ English and to considering it in assessing students’ academic performance. Meanwhile, the interviews revealed that the teachers’ negative language-related assessment attitude has been shaped by the view that they are non-responsible for correcting students’ English, and by the too many language errors noted in students’ performance. Finally, the teachers’ highly-rated language assessment self-efficacy beliefs did not match their actual assessment practices.

Abstract Background Nutrient stress (NS), one of the hallmarks of the tumour microenvironment, can render cancer cells tolerant to cytotoxicity. Fibroblasts, on the other hand, have cancer cell-like traits, such as plasticity and resiliency. Hence, this study aimed to evaluate the cytotoxicity of the drug on reseeded human U87 glioblastoma (GBM) cells as well as on mouse L929 fibroblasts in the form of monolayer and colonies that grew after NS induction. Results No treatment for 48 h showed a statistically significant difference in U87 cell viability when compared to the 50% hypothetical value. However, temozolomide (TMZ) (151.0 µg/ml) and azithromycin (AZI) (92.0 µg/ml) significantly diminished the number of U87 cell colonies compared to the untreated control, and AZI also outperformed doxycycline (DOXY) (147.0 µg/ml). L929 fibroblasts survived NS, but the cytotoxicity of AZI, DOXY, and AZI + DOXY (92.0 + 147.0 µg/ml) substantially increased than in L929 fibroblasts without NS induction. Conclusions The present findings suggest that NS does not inevitably contribute to cytotoxic drug tolerance in GBM cells. In addition, although fibroblasts can withstand NS, they can also become susceptible to cytotoxic drug-induced death; nevertheless, the type of drug may play a role. Graphical Abstract

Abstract Ecofriendly and stable Fuel Microemulsions based on renewable components were prepared through solubilizing ethanol in diesel and waste cooking oil blend (4:1). New diquaternary ammonium ionic liquids (3a & 3b) were synthesized through a quaternization reaction of the synthesized dihaloester with diethyl ethanolamine tridecantrioate and triethyl amine tridecantrioate, respectively. The chemical structures were elucidated by NMR spectroscopy. It was observed from DLS analyses that the ethanol particles in all samples have sizes between 4.77 to 11.22 nm. The distribution becomes narrower with the decrease in the ionic liquid concentrations. The fuel properties fall within the ASTM D975 acceptable specifications and are close to the neat diesel properties. The Cetane index were 53 and 53.5, heating values were 38.5 and 38.5 MJ/kg, viscosities were 2.91 and 2.98 mm2/s, densities were 8.26 and 8.29 g/mL and flash points were 49 °C and 48 °C for 3a1 and 3b1 microemulsions, respectively. The particle sizes of samples were examined by DLS for 160 days and they were significantly stable. The amount of ethanol solubilized increases with the increase in the amount of the synthesized ionic liquids and cosurfactant. The combustion calculations pointed out that the microemulsions 3a1 and 3b1 need 13.07 kg air/kg fuel and 12.79 kg air/kg fuel, respectively, which are less than the air required to combust the pure diesel. According to theoretical combustion, using ionic liquids saves the air consumption required for combustion and reduces the quantities of combustion products. The prepared microemulsions were successfully used as a diesel substitute due to their improved combustion properties than pure diesel and low pollution levels.

Background: Investigating the role of mitochondrial DNA (mtDNA) alterations and their impact on brain tumor progression remains a significant focus in cancer research. The research aimed to explore the specific contributions of mtDNA copy number changes and their correlations with patient survival, large mtDNA deletions, and TFAM mutations in brain tumor patients. Methods: A total of 41 patients with confirmed brain tumors underwent DNA extraction from both tumor tissues and blood samples. The relative mtDNA copy number in comparison to the nuclear genome was quantified using quantitative real-time polymerase chain reaction (qRT-PCR). Long-range PCR assessed largescale mtDNA deletions, and Sanger sequencing was applied to detect exon 4 TFAM mutations. Results: Analysis revealed significantly increased mtDNA copy numbers in brain tumor tissues (80.5%) compared to matched blood samples (P < .001). Median delta Ct (∆Ct) values were 7.35 in cancerous tissues and 11.81 in blood (P < .001), with median relative mtDNA content of 0.0123 and 0.0006, respectively (P < .001). Patients with higher mtDNA copy numbers experienced longer overall survival periods (P=.045) and notably favorable outcomes, particularly in high-grade tumor cases (P=.016). Furthermore, a singlenucleotide deletion was identified in exon 4 of TFAM in a patient with glioblastoma IV, while no large-scale mtDNA deletions were found in brain tumor patients. Conclusion: Our study strongly supports the role of increased mtDNA copy numbers as a reliable predictor for improved survival and positive outcomes in high-grade brain tumor patients.