scholarly journals Speech can produce jet-like transport relevant to asymptomatic spreading of virus

2020 ◽  
Vol 117 (41) ◽  
pp. 25237-25245 ◽  
Author(s):  
Manouk Abkarian ◽  
Simon Mendez ◽  
Nan Xue ◽  
Fan Yang ◽  
Howard A. Stone
Keyword(s):  
Social Interactions ◽  
Disease Transmission ◽  
Laboratory Experiments ◽  
Scaling Laws ◽  
Mitigation Strategies ◽  
Directed Transport ◽  
Transport Distance ◽  
Long Time ◽  
Phonetic Features

Many scientific reports document that asymptomatic and presymptomatic individuals contribute to the spread of COVID-19, probably during conversations in social interactions. Droplet emission occurs during speech, yet few studies document the flow to provide the transport mechanism. This lack of understanding prevents informed public health guidance for risk reduction and mitigation strategies, e.g., the “6-foot rule.” Here we analyze flows during breathing and speaking, including phonetic features, using orders-of-magnitude estimates, numerical simulations, and laboratory experiments. We document the spatiotemporal structure of the expelled airflow. Phonetic characteristics of plosive sounds like “P” lead to enhanced directed transport, including jet-like flows that entrain the surrounding air. We highlight three distinct temporal scaling laws for the transport distance of exhaled material including 1) transport over a short distance (<0.5 m) in a fraction of a second, with large angular variations due to the complexity of speech; 2) a longer distance, ∼1 m, where directed transport is driven by individual vortical puffs corresponding to plosive sounds; and 3) a distance out to about 2 m, or even farther, where sequential plosives in a sentence, corresponding effectively to a train of puffs, create conical, jet-like flows. The latter dictates the long-time transport in a conversation. We believe that this work will inform thinking about the role of ventilation, aerosol transport in disease transmission for humans and other animals, and yield a better understanding of linguistic aerodynamics, i.e., aerophonetics.

scholarly journals Fluid fragmentation shapes rain-induced foliar disease transmission

2015 ◽  
Vol 12 (104) ◽  
pp. 20141092 ◽  
Author(s):  
T. Gilet ◽  
L. Bourouiba
Keyword(s):  
Disease Transmission ◽  
Scaling Laws ◽  
Sessile Drop ◽  
Early Stage ◽  
Leaf Size ◽  
Pathogen Transmission ◽  
Mitigation Strategies ◽  
Plant Diseases ◽  
Foliar Disease ◽  
The Impact

Plant diseases represent a growing threat to the global food supply. The factors contributing to pathogen transmission from plant to plant remain poorly understood. Statistical correlations between rainfalls and plant disease outbreaks were reported; however, the detailed mechanisms linking the two were relegated to a black box. In this combined experimental and theoretical study, we focus on the impact dynamics of raindrops on infected leaves, one drop at a time. We find that the deposition range of most of the pathogen-bearing droplets is constrained by a hydrodynamical condition and we quantify the effect of leaf size and compliance on such constraint. Moreover, we identify and characterize two dominant fluid fragmentation scenarios as responsible for the dispersal of most pathogen-bearing droplets emitted from infected leaves: (i) the crescent-moon ejection is driven by the direct interaction between the impacting raindrop and the contaminated sessile drop and (ii) the inertial detachment is driven by the motion imparted to the leaf by the raindrop, leading to catapult-like droplet ejections. We find that at first, decreasing leaf size or increasing compliance reduces the range of pathogen-bearing droplets and the subsequent epidemic onset efficiency. However, this conclusion only applies for the crescent moon ejection. Above a certain compliance threshold a more effective mechanism of contaminated fluid ejection, the inertial detachment, emerges. This compliance threshold is determined by the ratio between the leaf velocity and the characteristic velocity of fluid fragmentation. The inertial detachment mechanism enhances the range of deposition of the larger contaminated droplets and suggests a change in epidemic onset pattern and a more efficient potential of infection of neighbouring plants. Dimensionless parameters and scaling laws are provided to rationalize our observations. Our results link for the first time the mechanical properties of foliage with the onset dynamics of foliar epidemics through the lens of fluid fragmentation. We discuss how the reported findings can inform the design of mitigation strategies acting at the early stage of a foliar disease outbreak.

scholarly journals Recommendations, Practices and Infrastructural Model for the Dental Radiology Set-up in Clinical and Academic Institutions in the COVID-19 Era

Biology ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 334
Author(s):  
Anu Sushanth. A ◽  
Kumar Chandan Srivastava ◽  
Deepti Shrivastava ◽  
Hala A. Hosni ◽  
Zafar Ali Khan ◽  
...  
Keyword(s):  
Disease Transmission ◽  
Dental Treatment ◽  
Dental Radiology ◽  
Dental Imaging ◽  
Work Routine ◽  
Long Time ◽  
Prevention Protocol ◽  
Global Catastrophe ◽  
Set Up

The pandemic of Coronavirus disease (COVID-19) has emerged as a global catastrophe that is plaguing mankind. In the past eight months since the world discovered about COVID-19, we learned a lot about server acute respiratory syndrome coronavirus 2 (SARS CoV-2) and perhaps there is much more to discover and understand about the virus. With the current understanding of the disease, we assume it will remain in an active state of transmission and progression among the community for a long time. Thus, it is advisable to adopt the disease’s prevention protocol in our daily and work routine. During this pandemic patient requiring dental treatment cannot be neglected and the role of dental imaging is crucial in delivering treatment. Hence, this article attempts to provide an evidence-based compilation about the mode of transmission and clinical features of COVID-19. It also throws light on the potential source of disease transmission in the dental radiology setting. In addition, it suggests preventive measures to curb the infection and infrastructural model of the clinical setting that will assist in achieving control over the disease transmission. This article intends to project a strategy about protocols, infrastructure, and daily activities in a dental radiology office that institutions can adopt with modifications according to their local scenario.

The Problem of Identifying and Modeling the Relationship between Monetary Factor and Inflation in the Russian Economy

2008 ◽  
pp. 61-76
Author(s):  
A. Porshakov ◽  
A. Ponomarenko
Keyword(s):  
Money Supply ◽  
Money Demand ◽  
Russian Economy ◽  
Long Run ◽  
Complex Approach ◽  
Wide Range ◽  
Long Time ◽  
The Relationship ◽  
Supply Side Factors

The role of monetary factor in generating inflationary processes in Russia has stimulated various debates in social and scientific circles for a relatively long time. The authors show that identification of the specificity of relationship between money and inflation requires a complex approach based on statistical modeling and involving a wide range of indicators relevant for the price changes in the economy. As a result a model of inflation for Russia implying the decomposition of inflation dynamics into demand-side and supply-side factors is suggested. The main conclusion drawn is that during the recent years the volume of inflationary pressures in the Russian economy has been determined by the deviation of money supply from money demand, rather than by money supply alone. At the same time, monetary factor has a long-run spread over time impact on inflation.

Value-driven issues throughout the development of sociological theory

2020 ◽  
pp. 147-160
Author(s):  
Gulbarshyn Chepurko ◽  
Valerii Pylypenko
Keyword(s):  
Social Interactions ◽  
Social System ◽  
Sociological Theory ◽  
Social Scientists ◽  
Social Sphere ◽  
Technological Advances ◽  
The Social ◽  
The Individual ◽  
Different Levels

The paper examines and compares how the major sociological theories treat axiological issues. Value-driven topics are analysed in view of their relevance to society in times of crisis, when both societal life and the very structure of society undergo dramatic change. Nowadays, social scientists around the world are also witnessing such a change due to the emergence of alternative schools of sociological thought (non-classical, interpretive, postmodern, etc.) and, subsequently, the necessity to revise the paradigms that have been existed in sociology so far. Since the above-mentioned approaches are often used to address value-related issues, building a solid theoretical framework for these studies takes on considerable significance. Furthermore, the paradigm revision has been prompted by technological advances changing all areas of people’s lives, especially social interactions. The global human community, integral in nature, is being formed, and production of human values now matters more than production of things; hence the “expansion” of value-focused perspectives in contemporary sociology. The authors give special attention to collectivities which are higher-order units of the social system. These units are described as well-organised action systems where each individual performs his/her specific role. Just as the role of an individual is distinct from that of the collectivity (because the individual and the collectivity are different as units), so too a distinction is drawn between the value and the norm — because they represent different levels of social relationships. Values are the main connecting element between the society’s cultural system and the social sphere while norms, for the most part, belong to the social system. Values serve primarily to maintain the pattern according to which the society is functioning at a given time; norms are essential to social integration. Apart from being the means of regulating social processes and relationships, norms embody the “principles” that can be applied beyond a particular social system. The authors underline that it is important for Ukrainian sociology to keep abreast of the latest developments in the field of axiology and make good use of those ideas because this is a prerequisite for its successful integration into the global sociological community.

SUSTAINABLE LIVELIHOOD THROUGH SKILL DEVELOPMENT AMONG RURAL YOUTH: ROLE OF MICRO-FINANCE IN THE DEVELOPMENTAL PARADIGM

2017 ◽  
Vol 14 (1) ◽  
pp. 156-173
Author(s):  
Vikram Singh
Keyword(s):  
Social Interactions ◽  
Skill Development ◽  
Well Being ◽  
Rural Youth ◽  
Inclusive Development ◽  
Sustainable Livelihood ◽  
Theoretical Understanding ◽  
Societal Structure ◽  
Policy Shifts

This  article  attempts to  analyse  the  process  of  sustainable  livelihood  through skill development and its conceptual and theoretical understanding in India with reference to rural youth. In India skill development is demanded for economic growth and inclusive development; hence the rural population cannot be overlooked. Employable skills alone have not been able to generate sufficient employment among rural youth or address/promote well-being and sustainable livelihood. Various frameworks associated with skill development leave scope for reforms to strengthen the implementation of various policy shifts in respect of rural development and government/non-government organisations. The process of skill development for rural youth through the establishment of institutions, launch of policy/programmes and their linkages with micro-finance are considered, as the distinctive nature and features of micro-finance in relation to the forces of societal structure, social relationships, and social interactions leading towards collective interests and norms that shape the lives of rural youth. Lastly, analysis is done and conclusions drawn on the basis of discussion.

ПОЕТИЧНА МОВОТВОРЧІСТЬ ЯК ВІДОБРАЖЕННЯ КОНЦЕПТУАЛЬНОЇ КАРТИНИ СВІТУ

2018 ◽  
pp. 166-174
Author(s):  
М. В. Дзисюк
Keyword(s):  
Semantic Space ◽  
Spiritual Values ◽  
Spatial Features ◽  
Filling Ability ◽  
Material Reality ◽  
Space Saving ◽  
Long Time ◽  
Literary Techniques ◽  
Linguistic Process

Definitions of concept and sphere of the concept are widely used in different aspects of modern linguistics. There is no single understanding of these notions and universal methodology of research has not been invented by linguists yet. This predetermines topicality of the article. The aim of our research is analysis, generalization, and systematization of different approaches to the interpretation of the notion ‘concept’ that exist in modern linguistics. It results in the following tasks: analysis of existing definitions of concept and its division into certain ranges and defining classification features. Modern linguists raise the questions of the conceptual and linguistic image of the world, the role of a human factor in its formation and interaction as in a linguistic process more frequently and it is defined as a fact in today’s linguistic scientific literature. The problem of individual language formation, poetic one in particular gains important meaning in this context. Ukrainian linguists use the notion of ‘concept’ for a long time now although they adhere to different views on its definition. Researches of the question define two major approaches in the analysis of the notion ‘concept’ that is linguistic-cognitive and linguistic-cultural. We can claim that words-concepts are agents between material reality and the ideal world that is synthesized in poetry, carriers of sense since with their help the versatility of the real world correlates with eternal spiritual values. Therefore, main features of the notion ‘concept’ in which objectively-cognitive and subjectively-creative features are combines are as follow sensual authenticity, time-spatial features, mediation between material and spiritual, semantic filling, ability to polysemy. A word with a generally symbolic meaning that is implemented in a language process through literary techniques typical for poet’s idiotype is the main core of the concept. The concept in poetic language formation by modern Uman poets is semantically integral, fulfilled, able to penetrate into other concepts and absorb semantically narrower images saving unity and semantic independence, varying numerous interpretations that project it in a certain semantic space, saving potential of real reflection.

„Arvīd, uz kurieni Tu aizgāji?”: Arvīda Griguļa personības loma Rakstnieku savienības vēsturē

2020 ◽  
pp. 74-84
Author(s):  
Madara Eversone
Keyword(s):  
20Th Century ◽  
Communist Party ◽  
Central Committee ◽  
State Archive ◽  
National Archives ◽  
Literary Heritage ◽  
Literary Process ◽  
Long Time ◽  
The Impact

The article aims to highlight the role of Arvīds Grigulis’ (1906–1989) personality in the Latvian Soviet literary process in the context of the Latvian Soviet Writers’ Union, attempting to discover the contradictions and significance of Arvīds Grigulis’ personality. Arvīds Grigulis was a long-time member of the Writers’ Union, a member of the Soviet nomenklatura, and an authority of the soviet literary process. His evaluations of pre-soviet literary heritage and writings of his contemporaries were often harsh and ruthless, and also influenced the development of the further literary process. The article is based on the documents of the Central Committee of the Latvian Communist Party, the Latvian Soviet Writers’ Union and the Communist Party local organization of the Latvian Soviet Writers’ Union that are available at the Latvian State Archive of the National Archives of Latvia, as well as memories of Grigulis’ contemporaries. It is concluded that the personality of the writer Arvīds Grigulis, although unfolding less in the context of the Writers’ Union, is essential for the exploration of the soviet literary process and events behind the scenes. The article mainly describes events and episodes taking place until 1965, when Arvīds Grigulis’ influence in the Writers’ Union was more remarkable. Individual and further studies should analyse changes and the impact of his decisions in the cultural process of the 70s and 80s of the 20th century.

Observation and Experimentation

2018 ◽  
Author(s):  
Massimiliano Di Ventra
Keyword(s):  
Laboratory Experiments ◽  
The Difference

This chapter expands on the previous one on the role of experiments in Science. It explains the difference between observations of phenomena and controlled laboratory experiments.

A Phenomenology of Rhythm

2018 ◽  
Author(s):  
Lexi Eikelboom
Keyword(s):  
Social Sciences ◽  
Social Interactions ◽  
Henri Lefebvre ◽  
Theoretical Perspectives ◽  
The Social ◽  
Analytical Importance ◽  
Jazz Performance

This chapter proposes a framework for approaching the theological significance of rhythm through phenomenology, prosody, and the social sciences. In accordance with the general categories of phenomenology established by Merleau-Ponty and the “rhythmanalysis” of Henri Lefebvre, the chapter investigates two experiences of rhythm: approaches to analysing the human encounter with rhythm in the reading of poetry and the role of rhythm in social interactions introduced through commonalities between rhythm in conversation and in jazz performance. These explorations establish two features of rhythm that are of analytical importance for the chapters that follow: (1) the synchronic and the diachronic as two necessary but distinct theoretical perspectives on rhythm, each of which emphasizes different features of rhythm and (2) the importance of interruption for understanding rhythm’s significance.

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