BACKGROUND: SARS-CoV-2 (COVID-19) is transmitted via infectious respiratory particles. Infectious respiratory particles are released when an infected person breathes, coughs, or speaks. Several studies have measured respiratory particle concentrations through focusing on activities such as breathing, coughing, and short speech. However, few studies have investigated the effect of speech duration. METHODS: This study aimed to clarify the effects of speech duration and volume on the respiratory particle concentration. Study participants were requested to speak at three voice volumes across five speech durations, generating 15 speech patterns. Participants spoke inside a clean booth where particle concentrations and voice volumes were measured and analyzed during speech. RESULTS: Our findings suggest that as speech duration increased, the aerosol number concentration also increased. Through focusing on individual differences, we considered there might be super-emitters who emit more aerosol particles than the average human. Two participants were identified as statistical outliers (aerosol number concentration, n = 1; mass concentration, n = 1). CONCLUSIONS Considering speech duration may improve our understanding of respiratory particle concentration dynamics. Two participants were identified as potential super-emitters.
Humans ; Male ; Speech/physiology* ; Adult ; Female ; COVID-19/transmission* ; Respiratory Aerosols and Droplets ; Voice ; SARS-CoV-2 ; Time Factors ; Young Adult ; Aerosols/analysis*

Background/Aims: The precise incidence of symptomatic uncomplicated diverticular disease (SUDD) and its effects on the quality of life (QOL) remain unclear, particularly in Asian patients with right-sided SUDD. We assess the prevalence of SUDD and its impact on QOL in a real-world population. Methods: Five institutional cohorts of patients who received outpatient treatment for unexplained abdominal symptoms from January 15, 2020 to March 31, 2022, were included. All patients underwent colonoscopy. SUDD was defined as the presence of recurrent abdominal symptoms, particularly pain in the lower right or left quadrant lasting > 24 hours in patients with diverticulosis at the site of pain. The 36-item short-form health survey was used to assess QOL. Results: Diverticula were identified in 108 of 361 patients. Among these 108 patients, 31% had SUDD, which was right-sided in 39% of cases.Of the 50 patients with right-sided diverticula, 36% had SUDD, as did 15 of 35 patients with left-sided diverticula (43%). Among the 33 patients with SUDD, diverticula were right-sided, left-sided, and bilateral in 39%, 45%, and 15% of patients, respectively. Diarrhea was more frequent in the SUDD group than in the non-SUDD group. Patients with SUDD had significantly lower physical, mental, and role/social component scores than those without SUDD. Conclusions It is important to recognize that patients with SUDD account for as high as 31% of outpatients with unexplained abdominal symptoms; these patients have diarrhea and a low QOL. The presence of right-sided SUDD was characteristic of Asian patients.