Face-masks save us from SARS-CoV-2 transmission

We present results on the infection risk from SARS-CoV-2 under different scenarios based on measured particle size-dependent mask penetration, measured total inward leakage, measured human aerosol emission for sizes from 10nm to 1mm, and re-hydration on inhalation. Well-mixed room models significantly underestimate the risk of infection for short and direct exposure. To this end, we estimate the upper bound for infection risk with the susceptible in the infectious exhalation cloud or wearing masks by having the masked susceptible inhale the entire exhalation of a masked infectious. Social distances without a mask, even at 3m between speaking individuals results in an upper bound of 90\% for risk of infection after a few minutes. If both wear a surgical mask, the risk of infection for the person speaking remains below 26\% even after 60 minutes. When both the infectious and susceptible wear a well-fitting FFP2 mask, the upper bound for risk is reduced by a factor of 60 compared to surgical masks. In both cases, face leakage is very important. For FFP2 masks, leakage is low in the nasal region and directed upward, which can be further reduced significantly by applying double-sided medical tape there. Considering that the calculated upper bound greatly overestimates the risk of infection, and the fact that with a poorly worn mask even the upper bound we calculated is very low, we conclude that wearing a mask, even with some leakage, provides excellent third party and self-protection

Sprottenborn: ein online mediiertes Rollenspiel

"In Politik und Wirtschaft werden die neuen Kommunikationsmedien zunehmend zur Gestaltung diskursiver Auseinandersetzungen genutzt. Internetbasierte Programmsysteme stehen zur Verfügung, die den Austausch von Argumenten und das Finden von Entscheidungen in moderierten/ mediierten Gruppen erleichtern sollen. Eines dieser Programme (ZENO) haben wir in einem dreimonatigen Rollenspiel (Sprottenborn) erprobt. Mit der Verwendung eines Rollenspiels zu Forschungszwecken betreten wir methodisch wenig sondiertes Terrain. Die im Internet niedergelegten schriftlichen Interaktionen und Kommunikationserfahrungen der Beteiligten Versuchspartner wurden systematisch erfasst und ausgewertet. Das Ziel der Untersuchung bestand darin, einen Beitrag zur Weiterentwicklung der Software und zum besseren Verständnis onlinetypischer psychosozialer Prozesse zu liefern. Hierbei konnte an gut bekannte Befunde der sozialpsychologischen Diskursforschung vergleichend angeknüpft werden. Das Projekt wurde in Kooperation mit dem Institut für Autonome intelligente Systeme (AiS, St. Augustin) und der AG-Online-Mediation (Berlin, WZB) durchgeführt." (Autorenreferat)"In politics and business, the new communications media are being used increasingly for the purpose of staging discursive conflicts. Program systems have been developed, which are designed to facilitate decision making in moderated or mediated groups. One of these programs, 'ZENO', was tested in a three-month online roll-playing encounter called 'Sprottenborn'. The use of role playing in a research context is methodologically new. The communication experiences and the written interactions among participating subjects were analyzed. The main purpose of our investigations was to make a contribution to further development of the software and to gain a more insightful view of typical online psychosocial processes. We compared them with well known results of sociopsychological discourse research. This project was carried out jointly by the Institute for Autonomous Intelligence Systems (AiS) in St. Augustin, Germany and the Working Group on Online Mediation at the Social Science Research Center Berlin (WZB) in Berlin, Germany." (author's abstract

Neither MRI, CT nor US is superior to diagnose tumors in the salivary glands – an extended case study

OBJECTIVES: Ultrasonography (US), computed tomography (CT) and magnetic resonance imaging (MRI) are the most common radiological procedures for the diagnosis of tumor-like lesions of the salivary glands. The aim of the present study was to determine whether MRI or CT provide additional information besides that delivered by US. STUDY DESIGN/METHODS: 109 patients with a tumor-like lesion of the salivary glands underwent surgery. MRI and CT were arranged in 73 and in 40 patients respectively, whereas all 109 patients were prospectively diagnosed by US. The results of CT, MRI and US were compared with the histological outcome. Furthermore, the recent rise in the number of CT and MRI studies was investigated. RESULTS: On CT and MRI, there was no rise in the percentage of malignant tumors or advanced surgical procedures. In respect of the radiological assessment of the lesion (benign/malignant) and the correct diagnosis, CT, MRI and US were comparable in terms of sensitivity, specificity and accuracy. No significant difference was found in the Chi-square test (p > 0.05). CONCLUSION: The evaluation of the preoperative results of CT, MRI and US revealed no advantage for CT or MRI; these procedures are only required in specific cases. An update or revision of the current preoperative diagnostic management is deemed necessary

Barriers to prompt and effective malaria treatment among the poorest population in Kenya

<p>Abstract</p> <p>Background</p> <p>Prompt access to effective malaria treatment is central to the success of malaria control worldwide, but few fevers are treated with effective anti-malarials within 24 hours of symptoms onset. The last two decades saw an upsurge of initiatives to improve access to effective malaria treatment in many parts of sub-Saharan Africa. Evidence suggests that the poorest populations remain least likely to seek prompt and effective treatment, but the factors that prevent them from accessing interventions are not well understood. With plans under way to subsidize ACT heavily in Kenya and other parts of Africa, there is urgent need to identify policy actions to promote access among the poor. This paper explores access barriers to effective malaria treatment among the poorest population in four malaria endemic districts in Kenya.</p> <p>Methods</p> <p>The study was conducted in the poorest areas of four malaria endemic districts in Kenya. Multiple data collection methods were applied including: a cross-sectional survey (n = 708 households); 24 focus group discussions; semi-structured interviews with health workers (n = 34); and patient exit interviews (n = 359).</p> <p>Results</p> <p>Multiple factors related to affordability, acceptability and availability interact to influence access to prompt and effective treatment. Regarding affordability, about 40 percent of individuals who self-treated using shop-bought drugs and 42 percent who visited a formal health facility reported not having enough money to pay for treatment, and having to adopt coping strategies including borrowing money and getting treatment on credit in order to access care. Other factors influencing affordability were seasonality of illness and income sources, transport costs, and unofficial payments. Regarding acceptability, the major interrelated factors identified were provider patient relationship, patient expectations, beliefs on illness causation, perceived effectiveness of treatment, distrust in the quality of care and poor adherence to treatment regimes. Availability barriers identified were related to facility opening hours, organization of health care services, drug and staff shortages.</p> <p><b>Conclusions</b></p> <p>Ensuring that all individuals suffering from malaria have prompt access to effective treatment remains a challenge for resource constrained health systems. Policy actions to address the multiple barriers of access should be designed around access dimensions, and should include broad interventions to revitalize the public health care system. Unless additional efforts are directed towards addressing access barriers among the poor and vulnerable, malaria will remain a major cause of morbidity and mortality in sub-Saharan Africa.</p

Cyber Physical Production Systems and Their Role for Decarbonization of Industry

Industry is the economic sector with the highest contribution to global Greenhouse Gas Emissions (GHG) and therewith plays a major for future decarbonization. The question arises whether cyber physical production systems (CPPS) as one core element of the digital transformation of industry can contribute here. To derive the most promising fields of action and investigate the role of CPPS a holistic perspective on the industry sector is necessary. Besides energy efficiency also fostering energy transition towards renewable sources as well as material efficiency turn out to be important leverages. Major CPPS based contributions can be expected through innovative, advanced control approaches—especially for complex production situations with changing products and diverse influencing factors. But also in other areas at least indirect contributions through CPPS can be expected, e.g. for identification of best practice technologies, to align energy demand and renewable energy supply or to support material efficiency-related improvements. Altogether, CPPS based potential for industry is estimated in a range of 15–25%

Experimental measurement of respiratory particles dispersed by wind instruments and analysis of the associated risk of infection transmission

Activities such as singing or playing a wind instrument release respiratory particles into the air that may contain pathogens and thus pose a risk for infection transmission. Here we report measurements of the size distribution, number, and volume concentration of exhaled particles from 31 healthy musicians playing 20 types of wind instruments using aerosol spectrometry and in-line holography in a strictly controlled cleanroom environment. We find that playing wind instruments carries a lower risk of airborne disease transmission than speaking or singing. We attribute this to the fact that the resonators of wind instruments act as filters for particles >10 $\mu$m in diameter. We have also measured the size-dependent filtering properties of different types of filters that can be used as instrument masks. Based on these measurements, we calculated the risk of airborne transmission of SARS-CoV-2 in different near- and far-field scenarios with and without masking and/or distancing. We conclude that in all cases where there is a possibility that the musician is infectious, the only safe measure to prevent airborne transmission of the disease is the use of well-fitting and well-filtering masks for the instrument and the susceptible person.Comment: 46 pages, 13 figures, 1 PDF with Supplementary Informatio

Size, concentration, and origin of human exhaled particles and their dependence on human factors with implications on infection transmission

Understanding infection transmission between individuals, as well as evaluating the efficacy of protective measures, are key issues in pandemics driven by human respiratory particles. The key is a quantitative understanding of the size and concentration of particles exhaled and their variability across the size range for a representative population of all ages, genders, and different activities. Here we present data from 132 healthy volunteers aged 5 to 80 years, measured over the entire particle size range for each individual. Conventional particle spectrometry was combined with in-line holography under well-controlled conditions for common activities such as breathing, speaking, singing, and shouting. We find age to be the most important parameter for the concentration of small exhale particles 15 µm from the oral cavity. PM5 concentration can vary by one order of magnitude within a person, while inter-person variability can span two orders of magnitude, largely explained by difference in age. We found no discernible inter-person variability for particles larger than 5 µm. Our results show that cumulative volume of PM5 is 2–8 times higher in adults than in children. In contrast, number and volume concentration of larger particles, which are produced predominantly in the upper respiratory tract, is largely independent of age. Finally, we examined different types of airborne-transmissible respiratory diseases and provided insights into possible modes of infection transmission with and without several types/fits of face masks