scholarly journals Spatiotemporal droplet dispersion measurements demonstrate face masks reduce risks from singing: results from the COvid aNd FacEmaSkS Study (CONFESS)

2021 ◽  
Author(s):  
Kai Man Alexander Ho ◽  
Hywel Davies ◽  
Ruth Epstein ◽  
Paul Bassett ◽  
Aine Hogan ◽  
...  
Keyword(s):  
Regression Models ◽  
Sound Intensity ◽  
Face Mask ◽  
Multilevel Regression ◽  
Planar Imaging ◽  
Mean Velocity ◽  
Velocity Magnitude ◽  
Droplet Production ◽  
The Impact ◽  
Droplet Transmission

Background: COVID-19 has restricted singing in communal worship. We sought to understand variations in droplet transmission and the impact of wearing face masks. Methods: Using rapid laser planar imaging, we measured droplets while participants exhaled, said "hello" or "snake", sang a note or "Happy Birthday", with and without surgical face masks. We measured mean velocity magnitude (MVM), time averaged droplet number (TADN) and maximum droplet number (MDN). Multilevel regression models were used. Results: In 20 participants, sound intensity was 71 Decibels (dB) for speaking and 85 dB for singing (p<0.001). MVM was similar for all tasks with no clear hierarchy between vocal tasks or people and >85% reduction wearing face masks. Droplet transmission varied widely, particularly for singing. Masks decreased TADN by 99% (p<0.001) and MDN by 98% (p<0.001) for singing and 86-97% for other tasks. Masks reduced variance by up to 48%. When wearing a mask, neither singing task transmitted more droplets than exhaling. Conclusions: Wide variation exists for droplet production. This significantly reduced when wearing face masks. Singing during religious worship wearing a face mask appears as safe as exhaling or talking. This has implications for UK public health guidance during the COVID-19 pandemic.

scholarly journals Spatiotemporal droplet dispersion measurements demonstrate face masks reduce risks from singing

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kai Man Alexander Ho ◽  
Hywel Davies ◽  
Ruth Epstein ◽  
Paul Bassett ◽  
Áine Hogan ◽  
...  
Keyword(s):  
Regression Models ◽  
Sound Intensity ◽  
Face Mask ◽  
Multilevel Regression ◽  
Planar Imaging ◽  
Mean Velocity ◽  
Velocity Magnitude ◽  
Droplet Production ◽  
The Impact ◽  
Droplet Transmission

AbstractCOVID-19 has restricted singing in communal worship. We sought to understand variations in droplet transmission and the impact of wearing face masks. Using rapid laser planar imaging, we measured droplets while participants exhaled, said ‘hello’ or ‘snake’, sang a note or ‘Happy Birthday’, with and without surgical face masks. We measured mean velocity magnitude (MVM), time averaged droplet number (TADN) and maximum droplet number (MDN). Multilevel regression models were used. In 20 participants, sound intensity was 71 dB for speaking and 85 dB for singing (p < 0.001). MVM was similar for all tasks with no clear hierarchy between vocal tasks or people and > 85% reduction wearing face masks. Droplet transmission varied widely, particularly for singing. Masks decreased TADN by 99% (p < 0.001) and MDN by 98% (p < 0.001) for singing and 86–97% for other tasks. Masks reduced variance by up to 48%. When wearing a mask, neither singing task transmitted more droplets than exhaling. In conclusion, wide variation exists for droplet production. This significantly reduced when wearing face masks. Singing during religious worship wearing a face mask appears as safe as exhaling or talking. This has implications for UK public health guidance during the COVID-19 pandemic.

scholarly journals Impact of roof geometry on cross-ventilation in vaulted buildings: a CFD study

2021 ◽  
Vol 2042 (1) ◽  
pp. 012106
Author(s):  
Milad Sadeghfar ◽  
Sadra Sahebzadeh
Keyword(s):  
Natural Ventilation ◽  
Volume Flow Rate ◽  
Large Set ◽  
Low Velocity ◽  
Mean Velocity ◽  
Flow Angle ◽  
High Rise ◽  
Velocity Magnitude ◽  
Flat Roof ◽  
The Impact

Abstract The roof geometry is an important parameter in determining the natural cross-ventilation in buildings. Although many studies have been performed on natural ventilation, the impact of the large set of vaulted roofs on the building cross-ventilation remains to be addressed. In this paper, high-fidelity computational fluid dynamics (CFD) simulations, validated with experimental data, are performed on five naturally ventilated buildings with two opposing windows, each with a specific type of vaulted roof and otherwise identical, in 0° incident flow angle, to assess the impact of vaulted roof geometry on the building cross-ventilation performance. The following vault geometries are investigated and compared against a flat-roof building with the same specifications: (i) segmental, (ii) low-rise pointed, (iii) mid-rise catenary (iv) high-rise pointed and (v) high-rise catenary. The results show that compared to the flat-roof building, the vaulted roofs cause a <5% decrease in volume flow rate and 16-29% increase in the average mean velocity magnitude at the occupants’ level. In vaulted buildings, the low-velocity regions of the flow are moved further away from the occupied zone towards the ceiling, thus providing a fresher air to the occupants. The results clarify the high potential of vaulted roofs for natural ventilation and sustainable design.

scholarly journals Course participation and the recognition and reporting of occupational ill-health

2019 ◽  
Vol 69 (7) ◽  
pp. 487-493
Author(s):  
J Beach ◽  
N Cherry
Keyword(s):  
Regression Models ◽  
Behavioural Change ◽  
Course Completion ◽  
Good Evidence ◽  
Annual Number ◽  
Multilevel Regression ◽  
Community Based ◽  
Weak Evidence ◽  
The Mean ◽  
The Impact

Abstract Background The Foundation Course in Occupational Medicine for community-based physicians was started in Alberta in 2012 and has since been implemented across Canada. As part of the evaluation of the first 4 years, two studies were initiated to assess the impact of the course on assessment of work-relatedness and case-reporting. Aims To determine whether assessment of work-relatedness, intention to report cases and number of cases reported to the Workers’ Compensation Board (WCB) changed during/after the course. Methods In study 1, course participants were asked to rate scenarios describing ill-health potentially resulting from work. They rated work-relatedness on a visual analogue scale and recorded whether they would report to the WCB. Assessments were made before the course started, after course completion or both. In study 2, numbers of reports to the WCB were documented for physicians giving consent, both for Foundation Course participants and a comparison group of community-based physicians. Multilevel regression models were fitted to allow for potential confounders and clustering within respondent. Results Among 102 physicians completing at least one set of scenario assessments, ratings of work-relatedness (β = 6.5; 95% CI 2.6–10.4) and likelihood of reporting to the WCB (OR = 1.9; 95% CI 1.2–3.1) increased significantly post-course. The mean annual number of cases reported to the WCB increased from 91.8 to 125.7 among the 35 Alberta physicians included in study 2. This change was only significant (P &lt; 0.05) on a one-sided test. Conclusion The two evaluative studies showed good evidence of changes in perceptions and intentions but only weak evidence of behavioural change.

FAKTOR DETERMINAN PENYALURAN KREDIT BANK PERSERO

2018 ◽  
Vol 23 (1) ◽  
pp. 60-71
Author(s):  
Wigiyanti Masodah
Keyword(s):  
Interest Rate ◽  
Linear Regression ◽  
Interest Rates ◽  
Regression Models ◽  
Linear Regression Models ◽  
Negative Impacts ◽  
Main Activity ◽  
The Impact ◽  
The Given ◽  
Multiple Linear Regression Models

Offering credit is the main activity of a Bank. There are some considerations when a bank offers credit, that includes Interest Rates, Inflation, and NPL. This study aims to find out the impact of Variable Interest Rates, Inflation variables and NPL variables on credit disbursed. The object in this study is state-owned banks. The method of analysis in this study uses multiple linear regression models. The results of the study have shown that Interest Rates and NPL gave some negative impacts on the given credit. Meanwhile, Inflation variable does not have a significant effect on credit given. Keywords: Interest Rate, Inflation, NPL, offered Credit.

The impact of SPY angiography on intraoperative decision making and outcomes for post-mastectomy reconstruction

2019 ◽  
pp. 1-5
Keyword(s):  
Decision Making ◽  
Logistic Regression ◽  
Skin Necrosis ◽  
Regression Models ◽  
Multivariable Analysis ◽  
P Value ◽  
Flap Necrosis ◽  
Single Institution ◽  
Logistic Regression Models ◽  
The Impact

Objective: While the use of intraoperative laser angiography (SPY) is increasing in mastectomy patients, its impact in the operating room to change the type of reconstruction performed has not been well described. The purpose of this study is to investigate whether SPY angiography influences post-mastectomy reconstruction decisions and outcomes. Methods and materials: A retrospective analysis of mastectomy patients with reconstruction at a single institution was performed from 2015-2017.All patients underwent intraoperative SPY after mastectomy but prior to reconstruction. SPY results were defined as ‘good’, ‘questionable’, ‘bad’, or ‘had skin excised’. Complications within 60 days of surgery were compared between those whose SPY results did not change the type of reconstruction done versus those who did. Preoperative and intraoperative variables were entered into multivariable logistic regression models if significant at the univariate level. A p-value <0.05 was considered significant. Results: 267 mastectomies were identified, 42 underwent a change in the type of planned reconstruction due to intraoperative SPY results. Of the 42 breasts that underwent a change in reconstruction, 6 had a ‘good’ SPY result, 10 ‘questionable’, 25 ‘bad’, and 2 ‘had areas excised’ (p<0.01). After multivariable analysis, predictors of skin necrosis included patients with ‘questionable’ SPY results (p<0.01, OR: 8.1, 95%CI: 2.06 – 32.2) and smokers (p<0.01, OR:5.7, 95%CI: 1.5 – 21.2). Predictors of any complication included a change in reconstruction (p<0.05, OR:4.5, 95%CI: 1.4-14.9) and ‘questionable’ SPY result (p<0.01, OR: 4.4, 95%CI: 1.6-14.9). Conclusion: SPY angiography results strongly influence intraoperative surgical decisions regarding the type of reconstruction performed. Patients most at risk for flap necrosis and complication post-mastectomy are those with questionable SPY results.

The effect of the implementation of a good medical practice booklet on nursing home residents’ drug prescriptions: a difference-in-differences analysis based on data from electronic pill dispensers (Preprint)

2019 ◽  
Author(s):  
Stéphane Sanchez ◽  
Cécile Payet ◽  
Marie Herr ◽  
Anne Dazinieras ◽  
Caroline Blochet ◽  
...  
Keyword(s):  
Nursing Homes ◽  
Medical Practice ◽  
Intervention Group ◽  
Medication Use ◽  
Nursing Home Residents ◽  
Control Group ◽  
Multilevel Regression ◽  
Difference In Differences ◽  
Good Medical Practice ◽  
The Impact

BACKGROUND The elderly are particularly exposed to adverse events from medication. Among the various strategies to reduce polypharmacy, educational approaches have shown promising results. OBJECTIVE We aimed to evaluate the impact of the implementation of a good medical practice booklet on polypharmacy in nursing homes. METHODS We identified nursing homes belonging to a geriatric care provider that had launched a policy of proper medication use using a good medical practice booklet delivered to prescribers and pharmacists. Data were derived from electronic pill dispensers. The effect of the intervention on polypharmacy was assessed with multilevel regression models, with a control group to account for natural trends over time. The main outcomes were the average daily number of times when medication was administered and the number of drugs with different presentation identifier codes per resident per month. RESULTS 96,216 residents from 519 nursing homes were included between 1 January 2011 and 31 December 2014. The intervention group and the control group both decreased their average daily use of medication (-0.05 and -0.06). The good medical practice booklet did not have a statistically significant effect (exponentiated difference-in-differences coefficient 1.00, 95% confidence interval 0.99-1.02, P=.45). CONCLUSIONS Although the good medical practice booklet itself did not seem effective in decreasing medication use, our data show the effectiveness of a higher-level policy to decrease polypharmacy.

scholarly journals COVID-19 Preventive Behaviours in Cameroon: A Six-Month Online National Survey

2021 ◽  
Vol 18 (5) ◽  
pp. 2554
Author(s):  
Joseph Nelson Siewe Fodjo ◽  
Leonard Ngarka ◽  
Wepnyu Y. Njamnshi ◽  
Leonard N. Nfor ◽  
Michel K. Mengnjo ◽  
...  
Keyword(s):  
Regression Models ◽  
Health Personnel ◽  
Online Survey ◽  
Preventive Measures ◽  
Face Mask ◽  
Logistic Regression Models ◽  
Adherence Score ◽  
Preventive Behaviour ◽  
Predictors Of Adherence

Since March 2020, the Cameroonian government implemented nationwide measures to stall COVID-19 transmission. However, little is known about how well these unprecedented measures are being observed as the pandemic evolves. We conducted a six-month online survey to assess the preventive behaviour of Cameroonian adults during the COVID-19 outbreak. A five-point adherence score was constructed based on self-reported observance of the following preventive measures: physical distancing, face mask use, hand hygiene, not touching one’s face, and covering the mouth when coughing or sneezing. Predictors of adherence were investigated using ordinal logistic regression models. Of the 7381 responses received from all ten regions, 73.3% were from male respondents and overall mean age was 32.8 ± 10.8 years. Overall mean adherence score was 3.96 ± 1.11 on a scale of 0–5. Mean weekly adherence scores were initially high, but gradually decreased over time accompanied by increasing incidence of COVID-19 during the last study weeks. Predictors for higher adherence included higher age, receiving COVID-19 information from health personnel, and agreeing with the necessity of lockdown measures. Meanwhile, experiencing flu-like symptoms was associated with poor adherence. Continuous observance of preventive measures should be encouraged among Cameroonians in the medium- to long-term to avoid a resurgence in COVID-19 infections.

scholarly journals Impact of Preharvest and Postharvest on Color Changes during Convective Drying of Mangoes

Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 490
Author(s):  
Alioune Diop ◽  
Jean–Michel Méot ◽  
Mathieu Léchaudel ◽  
Frédéric Chiroleu ◽  
Nafissatou Diop Ndiaye ◽  
...  
Keyword(s):  
Regression Models ◽  
Convective Drying ◽  
Color Changes ◽  
Ripening Time ◽  
Physico Chemical ◽  
C 30 ◽  
The Impact

The purpose of this study was to evaluate the impact of the harvest stage, ripening conditions and maturity on color changes of cv. ‘Cogshall’ and cv. ‘Kent’ variety mangoes during drying. A total of four harvests were undertaken, and the fruits were ripened at 20 and 35 °C for five different ripening times at each temperature. At each ripening time, mangoes were dried at 60 °C/30% RH/1.5 m/s for 5 h. A wide physico-chemical and color variability of fresh and dry pulp was created. The relationships according to the L*, H* and C* coordinates were established using mixed covariance regression models in relation to the above pre- and postharvest (preprocess) parameters. According to the L* coordinate results, browning during drying was not affected by the preprocess parameters. However, dried slices from mangoes ripened at 35 °C exhibited better retention of the initial chroma, and had a greater decrease in hue than dried slices from mangoes ripened at 20 °C. However, fresh mango color, successfully managed by the pre- and postharvest conditions, had more impact on dried mango color than the studied parameters. The preprocess parameters were effective levers for improving fresh mango color, and consequently dried mango color.

scholarly journals Impact of Face Masks on 6-Minute Walk Test in Healthy Volunteers

2021 ◽  
Vol 11 (1) ◽  
pp. 204589402098843
Author(s):  
Kevin M. Swiatek ◽  
Charnetta Lester ◽  
Nicole Ng ◽  
Saahil Golia ◽  
Janet Pinson ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Face Mask ◽  
Walk Test ◽  
Six Minute Walk Test ◽  
Significant Difference ◽  
6 Minute Walk Test ◽  
The Impact ◽  
Minute Walk

Our objective was to establish the impact of wearing a face mask on the outcome of six-minute walk test in healthy volunteers. In a study of 20 healthy volunteers who each completed two 6MWTs, one with a mask and one without, there was no difference in distance walked. However, there was a significant difference in perception of dyspnea between the two groups.

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