scholarly journals Experimental Methods of Investigating Airborne Indoor Virus-Transmissions Adapted to Several Ventilation Measures

Author(s):  
Lukas Siebler ◽  
Maurizio Calandri ◽  
Torben Rathje ◽  
Konstantinos Stergiaropoulos

This study introduces a principle, which unifies two experimental methods for airborne indoor virus-transmissions adapted to several ventilation measures. A first-time comparison of mechanical/natural ventilation and air purifiers with regard to infection risks is achieved. Effortful computational fluid dynamics demand detailed boundary conditions for accurate calculations of indoor airflows, which are often unknown. Hence a suitable, simple and generalized experimental set up for identifying the spatial and temporal infection risk for different ventilation measures is required. A trace gas method is suitable for mechanical and natural ventilation with outdoor air exchange. For an accurate assessment of air purifiers based on filtration a surrogate particle method is appropriate. The release of a controlled rate of either trace gas or particles simulates an infectious person releasing virus material. Surrounding substance concentration measurements identify the neighborhood exposure. One key aspect of the study is to prove that the requirement of concordant results of both methods is fulfilled. This is the only way to ensure that the comparison of different ventilation measures described above is reliable. Two examples (a two person office, several classrooms) show how practical both methods are and how the principle is applicable for different types and sizes of rooms.

Author(s):  
Lucía CASADO CASADO ◽  
Josep Ramon FUENTES I GASO

LABURPENA: Lan honetan, Europako Parlamentuaren eta Kontseiluaren 2010/75/EB Zuzentarauaren eragina aztertzen da. Horretarako, lehenik eta behin, Zuzentarauaren inguruabarrak eta alderdi azpimarragarrienak adierazten dira, eta, ondoren, ingurumen-ikuskaritzaren araubidean murgiltzen da. Oso gai berria da, ingurumen-ikuskaritzari buruzko gutxieneko araudi bat sortu den lehenengo aldia baita; orain arte, arau-baliorik gabeko Europako gomendio bat besterik ez zegoen. Hain zuzen ere, Estatu kideei gai horretan ezarritako betebeharrak aztertzen dira lanean; instalazioen gaineko ingurumen-ikuskaritzako sistema bat ezartzekoa, eta aurrezarritako ingurumen ikuskaritzako programen oinarrian egongo diren ikuskaritza planak osatzekoa, instalazioak bisitatzeko maiztasuna instalazioaren beraren motaren arabera finkatuta. Era berean, Zuzentaraua Espainiara egokitzeari buruzko oharrak egiten dira, aintzat hartuta orain dela gutxi ekainaren 11ko 5/2013 Legea onartu dela, kutsaduraren prebentzio eta kontrol integratuari buruzko uztailaren 1eko 16/2002 Legea eta hondakinen eta lurzoru kutsatuen gaineko uztailaren 28ko 22/2011 Legea aldatzen dituena. Lege berri horren eta egun izapidetzen ari diren garapen-erregelamenduen bidez, bermatuta geldituko da Zuzentarauaren egokitzea. RESUMEN: Este trabajo analiza el impacto de la Directiva 2010/75/UE del Parlamento Europeo y del Consejo, de 24 de noviembre de 2010, sobre las emisiones industriales en el régimen jurídico de la inspección ambiental. Con este fin, tras realizar una aproximación general a esta Directiva y señalar sus aspectos más destacables, se centra en el examen de la regulación de la inspección ambiental en ella contenida, aspecto muy novedoso por ser la primera vez que se incluye una regulación mínima de la inspección ambiental, que hasta ahora únicamente había sido objeto —a nivel comunitario— de una recomendación sin valor normativo, en una Directiva. Concretamente, se analizan las obligaciones establecidas para los Estados miembros en esta materia, que se traducen principalmente en la obligación de establecer un sistema de inspección medioambiental de las instalaciones y de formular planes de inspección a partir de los cuales se elaborarán programas de inspección medioambiental prefijada, que incluyan la frecuencia de las visitas a los emplazamientos para los distintos tipos de instalaciones. También se realizan algunos apuntes sobre la transposición de esta Directiva en España, teniendo en cuenta que recientemente se ha aprobado la Ley 5/2013, de 11 de junio, por la que se modifican la Ley 16/2002, de 1 de julio, de prevención y control integrados de la contaminación y la Ley 22/2011, de 28 de julio, de residuos y suelos contaminados, que, junto con su reglamento de desarrollo —actualmente en trámite—, garantizará la transposición de la Directiva. ABSTRACT: This study analyses the impact of Directive 2010/75/EU of the European Parliament and the Council, of 24 November 2010, on industrial emissions on the legislation governing environmental inspection. To this end, after providing a general discussion of the Directive and pointing out its most outstanding features, we focus on the regulation of environmental inspection that it contains. This is its most novel feature because it is the first time that a minimal regulation of environmental inspection has been included in a directive (to date, within the community, it had only been the object of a recommendation of no normative value). In particular, our study focuses on the obligations of the member states in this area, which are largely to set up a system by which installations can be environmentally inspected and inspection plans drafted on the basis of which programmes for routine environmental inspection will be drawn up that include the frequency of site visits for different types of installations. Also discussed is the transposition of the Directive in Spain, bearing in mind that Law 5/2013, of 11 June, has recently been passed to modify Law 16/2002, of 1 July, on the integrated prevention and control of pollution, and Law 22/2011, of 28 July on waste and polluted soil which, in conjunction with their regulation for implementation, guarantee the transposition of the Directive.


2020 ◽  
Author(s):  
Chang-Sheng Wang ◽  
Sabrina Monaco ◽  
Anh Ngoc Thai ◽  
Md. Shafiqur Rahman ◽  
Chen Wang ◽  
...  

A catalytic system comprised of a cobalt-diphosphine complex and a Lewis acid (LA) such as AlMe3 has been found to promote hydrocarbofunctionalization reactions of alkynes with Lewis basic and electron-deficient substrates such as formamides, pyridones, pyridines, and azole derivatives through site-selective C-H activation. Compared with known Ni/LA catalytic system for analogous transformations, the present catalytic system not only feature convenient set up using inexpensive and bench-stable precatalyst and ligand such as Co(acac)3 and 1,3-bis(diphenylphosphino)propane (dppp), but also display distinct site-selectivity toward C-H activation of pyridone and pyridine derivatives. In particular, a completely C4-selective alkenylation of pyridine has been achieved for the first time. Mechanistic stidies including DFT calculations on the Co/Al-catalyzed addition of formamide to alkyne have suggested that the reaction involves cleavage of the carbamoyl C-H bond as the rate-limiting step, which proceeds through a ligand-to-ligand hydrogen transfer (LLHT) mechanism leading to an alkyl(carbamoyl)cobalt intermediate.


Author(s):  
Vladimir A. Lapin ◽  
Erken S. Aldakhov ◽  
S. D. Aldakhov ◽  
A. B. Ali

For the first time in Almaty full passport of apartment stock of multiapartment building was carried out. The structure of the housing stock was revealed with the allocation of groups of buildings according to structural solutions and assessment of their seismic resistance. Based on the results of certification, quantitative estimates of failure probability values for different types of buildings were obtained. Formulas for estimation of quantitative value of seismic risk are obtained. The number of deaths in the estimated zem-shakes was estimated. The results of the assessments will be used for practical recommendations to reduce risk and expected losses in possible earthquakes.


Author(s):  
Jack Corbett ◽  
Wouter Veenendaal

Chapter 1 introduces the main arguments of the book; outlines the approach, method, and data; defines key terms; and provides a chapter outline. Global theories of democratization have systematically excluded small states, which make up roughly 20 per cent of countries. These cases debunk mainstream theories of why democratization succeeds or fails. This book brings small states into the comparative politics fold for the first time. It is organized thematically, with each chapter tackling one of the main theories from the democratization literature. Different types of data are examined—case studies and other documentary evidence, interviews and observation. Following an abductive approach, in addition to examining the veracity of existing theory, each chapter is also used to build an explanation of how democracy is practiced in small states. Specifically, we highlight how small state politics is shaped by personalization and informal politics, rather than formal institutional design.


2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
S Westley ◽  
H Creasy ◽  
R Mistry

Abstract Introduction The Queen Victoria Hospital (QVH) was designated a cancer and trauma hub during the COVID-19 pandemic. With this, a new virtual hand trauma clinic was set up. We assess accuracy of assessment within this virtual set-up with comparison to pre COVID-19 face-to-face assessment. Method Two weeks of clinic sessions during and pre lockdown were analysed. Initial assessment was compared with the patient's operation note. Results In the pre COVID-19 two-week period 129 face-to-face appointments were analysed. Of 99 patients that required surgery 77 (78%) had an accurate assessment. 6 were overestimated, 12 were underestimated. 189 patients were seen over two weeks during lockdown via telephone or video call. Accuracy of assessment increased with seniority of the clinician. Of 126 patients that required an operation 109 (87%) had an accurate assessment; all structures injured were correctly predicted. 12 were overestimated, 5 had their injury underestimated. Conclusions The new virtual clinic allowed patients to be remotely assessed during lockdown, reducing footfall and unnecessary journeys. We found that virtual clinic assessments are accurate, and no patient underwent an unnecessary procedure. Using a telephone call plus photo gave similar accuracy as a video call. Virtual assessment was more accurate than face-to-face assessment.


2021 ◽  
Vol 7 (3) ◽  
pp. 38
Author(s):  
Alexandra Korotaeva ◽  
Danzan Mansorunov ◽  
Natalya Apanovich ◽  
Anna Kuzevanova ◽  
Alexander Karpukhin

Neuroendocrine neoplasms (NEN) are infrequent malignant tumors of a neuroendocrine nature that arise in various organs. They occur most frequently in the lungs, intestines, stomach and pancreas. Molecular diagnostics and prognosis of NEN development are highly relevant. The role of clinical biomarkers can be played by microRNAs (miRNAs). This work is devoted to the analysis of data on miRNA expression in NENs. For the first time, a search for specificity or a community of their functional characteristics in different types of NEN was carried out. Their properties as biomarkers were also analyzed. To date, more than 100 miRNAs have been characterized as differentially expressed and significant for the development of NEN tumors. Only about 10% of the studied miRNAs are expressed in several types of NEN; differential expression of the remaining 90% was found only in tumors of specific localizations. A significant number of miRNAs have been identified as potential biomarkers. However, only a few miRNAs have values that characterized their quality as markers. The analysis demonstrates the predominant specific expression of miRNA in each studied type of NEN. This indicates that miRNA’s functional features are predominantly influenced by the tissue in which they are formed.


2021 ◽  
Vol 10 (8) ◽  
pp. 1613
Author(s):  
Alessandro Crosio ◽  
Giulia Ronchi ◽  
Benedetta Elena Fornasari ◽  
Simonetta Odella ◽  
Stefania Raimondo ◽  
...  

As a consequence of trauma or surgical interventions on peripheral nerves, scar tissue can form, interfering with the capacity of the nerve to regenerate properly. Scar tissue may also lead to traction neuropathies, with functional dysfunction and pain for the patient. The search for effective antiadhesion products to prevent scar tissue formation has, therefore, become an important clinical challenge. In this review, we perform extensive research on the PubMed database, retrieving experimental papers on the prevention of peripheral nerve scarring. Different parameters have been considered and discussed, including the animal and nerve models used and the experimental methods employed to simulate and evaluate scar formation. An overview of the different types of antiadhesion devices and strategies investigated in experimental models is also provided. To successfully evaluate the efficacy of new antiscarring agents, it is necessary to have reliable animal models mimicking the complications of peripheral nerve scarring and also standard and quantitative parameters to evaluate perineural scars. So far, there are no standardized methods used in experimental research, and it is, therefore, difficult to compare the results of the different antiadhesion devices.


2021 ◽  
Vol 13 (12) ◽  
pp. 6875
Author(s):  
Irene Poza-Casado ◽  
Raquel Gil-Valverde ◽  
Alberto Meiss ◽  
Miguel Ángel Padilla-Marcos

Indoor air quality (IAQ) in educational buildings is a key element of the students’ well-being and academic performance. Window-opening behavior and air infiltration, generally used as the sole ventilation sources in existing educational buildings, often lead to unhealthy levels of indoor pollutants and energy waste. This paper evaluates the conditions of natural ventilation in classrooms in order to study how climate conditions affect energy waste. For that purpose, the impact of the air infiltration both on the IAQ and on the efficiency of the ventilation was evaluated in two university classrooms with natural ventilation in the Continental area of Spain. The research methodology was based on site sensors to analyze IAQ parameters such as CO2, Total Volatile Organic Compounds (TVOC), Particulate Matter (PM), and other climate parameters for a week during the cold season. Airtightness was then assessed within the classrooms and the close built environment by means of pressurization tests, and infiltration rates were estimated. The obtained results were used to set up a Computational Fluid Dynamics (CFD) model to evaluate the age of the local air and the ventilation efficiency value. The results revealed that ventilation cannot rely only on air infiltration, and, therefore, specific controlled ventilation strategies should be implemented to improve IAQ and to avoid excessive energy loss.


Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2197
Author(s):  
Nayara Rodrigues Marques Sakiyama ◽  
Jurgen Frick ◽  
Timea Bejat ◽  
Harald Garrecht

Predicting building air change rates is a challenge for designers seeking to deal with natural ventilation, a more and more popular passive strategy. Among the methods available for this task, computational fluid dynamics (CFD) appears the most compelling, in ascending use. However, CFD simulations require a range of settings and skills that inhibit its wide application. With the primary goal of providing a pragmatic CFD application to promote wind-driven ventilation assessments at the design phase, this paper presents a study that investigates natural ventilation integrating 3D parametric modeling and CFD. From pre- to post-processing, the workflow addresses all simulation steps: geometry and weather definition, including incident wind directions, a model set up, control, results’ edition, and visualization. Both indoor air velocities and air change rates (ACH) were calculated within the procedure, which used a test house and air measurements as a reference. The study explores alternatives in the 3D design platform’s frame to display and compute ACH and parametrically generate surfaces where air velocities are computed. The paper also discusses the effectiveness of the reference building’s natural ventilation by analyzing the CFD outputs. The proposed approach assists the practical use of CFD by designers, providing detailed information about the numerical model, as well as enabling the means to generate the cases, visualize, and post-process the results.


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