Detection of Methane Eructation Peaks in Dairy Cows at a Robotic Milking Station Using Signal Processing

The aim of this study was to investigate the use of signal processing to detect eructation peaks in CH4 released by cows during robotic milking, and to compare recordings from three gas analysers (Guardian SP and NG, and IRMAX) differing in volume of air sampled and response time. To allow comparison of gas analysers using the signal processing approach, CH4 in air (parts per million) was measured by each analyser at the same time and continuously every second from the feed bin of a robotic milking station. Peak analysis software was used to extract maximum CH4 amplitude (ppm) from the concentration signal during each milking. A total of 5512 CH4 spot measurements were recorded from 65 cows during three consecutive sampling periods. Data were analysed with a linear mixed model including analyser × period, parity, and days in milk as fixed effects, and cow ID as a random effect. In period one, air sampling volume and recorded CH4 concentration were the same for all analysers. In periods two and three, air sampling volume was increased for IRMAX, resulting in higher CH4 concentrations recorded by IRMAX and lower concentrations recorded by Guardian SP (p < 0.001), particularly in period three, but no change in average concentrations measured by Guardian NG across periods. Measurements by Guardian SP and IRMAX had the highest correlation; Guardian SP and NG produced similar repeatability and detected more variation among cows compared with IRMAX. The findings show that signal processing can provide a reliable and accurate means to detect CH4 eructations from animals when using different gas analysers.

Detection of SARS-CoV-2 in Exhaled Breath from Non-Hospitalized COVID-19-Infected Individuals: A Proof-of-Concept Study

Background: The diagnosis of COVID-19 is based on detection of SARS-CoV-2 in oro-/nasopharyngel swabs, but because of uncomfortness and minor risk for the tested individual during the swab procedure, detection of SARS-CoV-2 has been investigated in other biological matrixes.Methods: In this proof-of-concept study, confirmed SARS-CoV-2-infected individuals performed a daily air sample through five days. Air samples were obtained through a non-invasive electrostatic air sampler. Detection of SARS-CoV-2 RNA were determined with qRT-PCR. The association of positive samples with clinical characteristics was evaluated through mixed-effect models.Results: We obtained 665 air samples from 111 included patients with confirmed SARS-CoV-2 infection. Overall, 52 individuals (46.8%) had at least one positive air sample, and 129 (19.4%) air samples were positive for SARS-CoV-2. Patients with symptoms or a symptom duration ≤ four days had significantly higher odds of having a positive air sample. Cycle threshold values were significantly lower in samples obtained ≤ 4 days from symptom onset. Neither variant of SARS-CoV-2 nor method of air sampling were associated with a positive air sample.Conclusion: We demonstrate that SARS-CoV-2 is detectable in human breath, and suggest further evaluation of air sampling considering the non-invasive, point-of-care method.

Experimnetal Investigation on Outdoor and Indoor PM2.5 and PM10 in Supermarkets in Bandung During Covid-19 Pandemic

During the Covid-19 pandemic, the number of visitor at the trade center in Bandung was much reduced as compared to before pandemic, which was only about 30% of normal conditions. The present study is to investigate particulate concentrations of PM2.5 and PM10 in three supermarkets in Bandung, namely Kosambi, Batununggal Modern and Cinunuk supermarkets during the pandemic of Covid-19. Air sampling was measured using a particulate counter CEM DT96 for 11 hours, from 06:00 AM to 5:00 PM, local time. The results showed that the average of outdoor and indoor concentrations of PM10 in two supermarkets (Batununggal Modern and Griya Cinunuk) was lower than standard during that 11 hours. As for the outdoor concentrations of PM2.5, both markets exceeded the standard for several hours in the morning. In general, it can be concluded that the outdoor and indoor concentrations of PM2.5 and PM.10 during pandemic were below the standard, except in the morning before 10:00 AM