Global research trends in benign paroxysmal positional vertigo: a bibliometric analysis.

Background: Benign paroxysmal positional vertigo is the most common disease in which vertigo is the main clinical manifestation, and it has become a global medical problem, affecting a wide range of areas and seriously affecting the quality of human life. Objective: This article presents an analysis of the current characteristics of BPPV-related research and summarizes the current hot topics and trends, with the goal of inspiring future research into the prevention and treatment of BPPV, thereby improving the differential diagnosis and prevention of peripheral vertigo. Methods: A bibliometric approach was used to collect 1,219 eligible studies on BPPV from four databases-PubMed, Embase, Scopus, and Web of Science-published between 1974 and 2022. The characteristics and status of the accumulated scientific output were processed using R and VOSviewer so that we could visualize any trends or hotspots. Results: The results showed a significant increase in the annual number of publications, with an average annual growth rate of 21.58%. A possible reason for the especially pronounced peak in 2021 was an increase in the prevalence of BPPV as a result of COVID-19. The new coronavirus became a focus of research in 2021. A total of 3,876 authors (of whom 1,097 were first authors) published articles in 307 different journals; 15.7% of the articles were published in Acta Oto-Larygologica, Otology and Neurotology, and Frontiers in Neurology. Acta Oto-Laryngologica was well ahead of the other journals in terms of growth rate and number of articles published. American scholars generated the largest number of articles overall, and the USA was involved in the greatest number of international collaborations, followed by Italy and China. The themes of the research centered around three topics, namely the treatment of BPPV, its influencing factors, and diagnosis. Conclusions: There has been a major increase in BPPV-related research over the last 50 years, leading to an increase in related articles and rapid development of the field. Key directions for future research include the improvement of individualized treatment for residual symptoms after initial treatment of BPPV among the elderly; effective control of comorbidities such as osteoporosis; and secondary inner ear disease, such as Ménière's disease.

A viable approach for commercial VFAs production from sludge: Liquid fermentation in anaerobic dynamic membrane reactor.

A novel strategy of liquid fermentation using anaerobic dynamic membrane reactor (AnDMBR) was proposed to enhance volatile fatty acids (VFAs) production from sewage sludge. Results indicated that liquid sludge fermentation in AnDMBR had the potential in commercial VFAs production. VFAs productivity and concentration as well as substrate conversion rate could reach as high as 7.8 kg VFA-COD/m3 d, 60 g/L and 0.38 kg VFA-COD/kg VS, respectively. Moreover, dynamic membrane was stably operated for approximately 70 days. During the operational period, membrane flux was increased from 6.25 to 25 L/m2 d and only once online membrane cleaning was implemented. Results of microbial analyses showed bacterial richness and evenness in AnDMBR were increased by membrane separation and organic loading rate (OLR) increase, but reduced by excessive OLR, which should led the variations in the performances of AnDMBR. Furthermore, the necessity of liquid sludge fermentation for VFAs production was further confirmed by economic assessment and the bioavailability analysis of the residual solids in pretreated sludge. The residual solid was proved to be not conducive to enhance VFAs yield. Conversely, the energy consumption for VFAs production could be reduced from over 100 to below 20 kwh/kg VFAs by avoiding the "useless" residual solids entering into fermenters.

Evaluation of artificial tears on cornea epithelium healing.

AIM: To observe the efficacy of different artificial eye drops on corneal epithelium healing in rabbit. METHODS: Thirty-five rabbits with 6 mm diameter central corneal epithelium removed were randomly assigned to six groups: 0.9% normal saline (NS) group, 0.1% hyaluronate (HA) group, 0.3% HA group, Tears Naturale Free® (TNF) group, 0.4% polyethylene glycol (PEG) group, 0.5% carboxymethyl cellulose (CMC) group and blank control group. Treatments were administered topically four times daily. Corneal epithelium healing was evaluated by the percentage reduction in wound area at 24, 36, 48, 60, and 72h after removal of the corneal epithelium. Cornea re-epithelialization was also assessed by histological analysis and electron microscopy. RESULTS: All corneal wounds completely re-epithelialized in less than 72h. The average re-epithelialization time was 47.61±4.25h in the 0.3% HA group and 49.72±1.05h in the 0.9% NS group, followed by 0.1% HA, TNF, 0.4% PEG, 0.5% CMC, and lastly by the control group. Compared to the control group, there were significant differences among 0.3% HA, 0.9% NS, PEG, and TNF (P<0.05) groups. At the first 24h, re-epithelialization at the 0.3% HA, TNF, and 0.9% NS treatment groups were significantly faster than the other groups. At 48h post-wounding, corneal epithelium is nearly completing re-epithelialization at 0.3% HA and 0.9% NS treatment groups. Electron microscopy revealed that there were a large number of vacuoles in the cells of the 0.9% NS group at 72h. CONCLUSION: Artificial tears promote corneal re-epithelium varied in the efficacy. Obviously, all artificial eye drops better than blank group. In the process of corneal healing, corneal epithelium cells suffered from hypoxia caused by NS.