Lubricating oils are employed in machinery to minimise friction, remove heat and wear particles, protect against corrosion etc. Mineral base oils are derived from natural crude oil through a distillation process and are divided into five main groups depending on volume of sulphur, saturate and viscosity index, according to the American Petroleum Institute (API). As lubricating base oil oxidises, acidic by-products are formed and oil viscosity increases due to progressive polycondensation of higher molecular weight products. In this work, thick film (TF) potentiometric sensors based on ion-selective electrodes (ISE) have been developed for oil acidity measurement to enable online oil condition monitoring. A TF ruthenium oxide (RuO 2 ) working electrode and three types of TF reference electrodes were fabricated and tested in oxidised base oil samples prepared at the Shell Houston laboratories. The TF sensors were evaluated by comparison with acid number (AN) measurement and also compared with oil conductivity measurements using impedance spectroscopy. The results show that the conductivity, viscosity and AN of the oil samples increase with the level of oil oxidisation. The output of the TF sensors detected the acidity increase of the oxidised oil samples at both 50 and 80 °C and displayed a linear relationship with oil AN.

Lubricating oil of moving parts is a critical factor for the performance and longevity of cars and industrial engines. The lubricant degradation occurring during application can be detrimental to the proper operation of lubricated machines if the oil is not changed in a timely manner. However, the oil degradation process is often influenced by a number of parameters, such as the operating temperature and contamination. This offers a challenge to oil monitoring technologies. This study investigates the feasibility of detecting changes in oil acidity using Ion Selective Electrodes (ISE) fabricated using thick-film (TF) screen printing technology. The working electrode is a TF Ruthenium Oxide (RuO 2 ) ISE; the reference electrodes are three different types of TF reference electrodes and commercial glass pH reference electrode. Artificially degraded oil samples from oxidation tests and model oils produced by adding acid have been used for the evaluation of the sensors. Acid Number (AN) of all oil samples was obtained using conventional titration method. The results show that the TF electrodes responded linearly to the change in oil acidity under different temperatures. Their sensitivity in detecting oil acidity in the model oils is found to be much higher than that of the commercial electrode. Initial analysis also shows that the sensor responses decrease as the temperature increases.

Introduction Lophomoniasis is caused by Lophomonas spp., a new emerging protozoan, which commonly affects the human lower respiratory tract. The Lophomonas parasite mostly lives commensally in the hindgut of cockroaches. Case Presentation We present the case of a 33-year-old woman, 30 weeks pregnant, who had severe COVID-19. She was intubated upon admission and began the routine COVID-19 treatment. To rule out possible super infection dual with COVID-19, microscopic examination of the patient's mini-bronchoalveolar lavage (mini-BAL) specimen, revealed L. blattarum, which was identified by the SSU rRNA-PCR and sequencing approaches (accession number: MZ093069). According to that, the patient was treated successfully with metronidazole. Conclusion To prevent serious complications, lophomoniasis should be listed in co-morbidity cases of COVID-19 infection during the COVID-19 pandemic worldwide. To the best of our knowledge, this is the first co-infection of Lophomonas blattarum and COVID-19 in the world which has been confirmed using a molecular approach.

Background Dirofilaria immitis is a mosquito-borne filarial nematode, which infects primarily wild and domestic canids, causing cardiopulmonary dirofilariasis. The aim of the present study was to determine the prevalence and characterize molecular features of D. immitis in road killed canids, northern Iran. Methods The carcasses of 53 road killed canids including 18 dogs (Canis familiaris), and 35 golden jackals (C. aureus) were necropsied in both Mazanderan and Guilan provinces, northern Iran. The molecular analyses were conducted based on the cytochrome oxidase (Cox) 1 and 18S ribosomal RNA (rRNA) genes. Results The heartworm infection was found in 55.6% of dogs and 22.9% of jackals. Our study revealed significantly higher prevalence of D. immitis in dogs compared to jackals (P = 0.031). The prevalence of D. immitis was no statistically significant between males and females in both dogs and jackal (P > 0.05). Comparison of the Cox1 gene sequences with available data in the GenBank illustrated 100% similarity with D. immitis isolates from different hosts in European, Asian, and South American continents. Moreover, the 18S rRNA gene sequences showed 100% identity with dog isolates from Japan and French Guiana. Conclusions This study confirms the high prevalence of D. immitis in dogs and jackals of northern Iran. Developing control programs to prevent transmission of the disease is necessary for dogs and humans in the study areas.