scholarly journals Modeling the waves of Covid-19

2021 ◽  
Author(s):  
Ivan Cherednik
Keyword(s):  
Transmission Rate ◽  
Herd Immunity ◽  
Two Phase ◽  
Protective Measures ◽  
The Usa ◽  
The Waves ◽  
Phase Solution ◽  
Very High ◽  
Initial Transmission

Classical approaches to modeling the spread of epidemics are based on two assumptions: the exponential growth of the total number of infections and the saturation due to the herd immunity. With Covid-19, the growth is essentially power-type, especially during the middle stages, and the saturation is currently mostly due to the protective measures. Focusing on these features and the role of epidemic management, we obtain differential equations for the total number of detected cases of Covid-19, which describe the actual curves in many countries almost with the accuracy of physics laws. The two-phase solution we propose worked very well almost for the whole periods of the spread practically in all countries we analyzed that reached the saturation during the first waves. Bessel functions play the key role in our approach. Due to a very small number of parameters, namely, the initial transmission rate and the intensity of the hard and soft measures, we obtain a convincing explanation of the surprising uniformity of the curves of the total numbers of detected infections in many different areas. This theory can serve as a tool for forecasting the epidemic spread and evaluating the efficiency of the protective measures, which is very much needed for epidemics. For instance, the accuracy was very high for the early projection for the 3rd wave in the USA; projections for India, South Africa and UK are considered.

scholarly journals Modeling the spread of Covid-19 under active management

2020 ◽  
Author(s):  
Ivan Cherednik
Keyword(s):  
Western Europe ◽  
Transmission Rate ◽  
Herd Immunity ◽  
Active Management ◽  
Two Phase ◽  
Protective Measures ◽  
The Usa ◽  
Phase Solution ◽  
Late Stages

Classical approaches to modeling the spread of epidemics are based on two assumptions: the exponential growth of the total number of infections and the saturation due to the herd immunity. With Covid-19, the growth is essentially power-type, especially during the middle stages, and the saturation is currently mostly due to the protective measures. Focusing on these features and the role of epidemic management, we obtain differential equations for the total number of detected cases of Covid-19, which describe the actual curves in many countries almost with the accuracy of physics laws. The two-phase solution we propose works very well almost for the whole periods of the spread practically in all countries we analyzed that reached the saturation during the first waves. Bessel functions play the key role in our approach. Due to a very small number of parameters, namely, the initial transmission rate and the intensity of the hard and soft measures, we obtain a convincing explanation of the surprising uniformity of the curves of the total numbers of detected infections in many different areas. This theory can serve as a tool for forecasting the epidemic spread and evaluating the efficiency of the protective measures, which is very much needed for epidemics. As its practical application, the computer programs aimed at providing projections for late stages of Covid-19 proved to be remarkably stable in many countries, including Western Europe, the USA and some in Asia. We provide a projection for the saturation of the 3rd wave in the USA: the corresponding number of total, detected or not, cases can presumably reach then the herd immunity levels (G-strains). This can be used to analyze the efficiency of the vaccinations.

scholarly journals A surprising formula for the spread of Covid-19 under aggressive management

2020 ◽  
Author(s):  
Ivan Cherednik
Keyword(s):  
Bessel Functions ◽  
Transmission Rate ◽  
High Accuracy ◽  
Viral Fitness ◽  
Prevention Measures ◽  
Aggressive Management ◽  
Normal Frequency ◽  
The Usa ◽  
Momentum Management ◽  
Initial Transmission

AbstractWe propose an algebraic-type formula that describes with high accuracy the total number of detected infections for the Covid-19 pandemic in many countries. Our 2-phase formula can be used as a powerful forecasting tool. It is based on the author’s new theory of momentum management of epidemics; Bessel functions are employed. Its 3 parameters are the initial transmission rate, reflecting the viral fitness and “normal” frequency of contacts in the infected areas, and the intensity of prevention measures at phases 1, 2. Austria, Brazil, Germany, Japan, India, Israel, Italy, the Netherlands, Sweden, Switzerland, UK, and the USA are considered. For the USA, all states are processed independently and some “interaction” is added; the forecasting software is provided.

scholarly journals Socio-demographic factors associated with self-protecting behavior during the Covid-19 pandemic

2021 ◽  
Vol 34 (2) ◽  
pp. 691-738 ◽  
Author(s):  
Nicholas W. Papageorge ◽  
Matthew V. Zahn ◽  
Michèle Belot ◽  
Eline van den Broek-Altenburg ◽  
Syngjoo Choi ◽  
...  
Keyword(s):  
Housing Quality ◽  
Socioeconomic Differences ◽  
Protective Behaviors ◽  
Protective Measures ◽  
Factors Associated ◽  
Work Arrangements ◽  
Health Related ◽  
The Usa ◽  
Socio Demographic Factors

AbstractGiven the role of human behavior in the spread of disease, it is vital to understand what drives people to engage in or refrain from health-related behaviors during a pandemic. This paper examines factors associated with the adoption of self-protective health behaviors, such as social distancing and mask wearing, at the start of the Covid-19 pandemic in the USA. These behaviors not only reduce an individual’s own risk of infection but also limit the spread of disease to others. Despite these dual benefits, universal adoption of these behaviors is not assured. We focus on the role of socioeconomic differences in explaining behavior, relying on data collected in April 2020 during the early stages of the Covid-19 pandemic. The data include information on income, gender and race along with unique variables relevant to the current pandemic, such as work arrangements and housing quality. We find that higher income is associated with larger changes in self-protective behaviors. These gradients are partially explained by the fact that people with less income are more likely to report circumstances that make adopting self-protective behaviors more difficult, such as an inability to tele-work. Both in the USA and elsewhere, policies that assume universal compliance with self-protective measures—or that otherwise do not account for socioeconomic differences in the costs of doing so—are unlikely to be effective or sustainable.

THE ROLE OF GRASSLAND IN MANAGEMENT

1968 ◽  
pp. 44-49
Author(s):  
B.K. Cameron
Keyword(s):  
Soil Temperature ◽  
Annual Rainfall ◽  
Silt Loam ◽  
Average Annual Rainfall ◽  
Very High ◽  
Wilting Point

THE PROPERTY to be discussed is a mixed sheep and cropping unit, situated ei ht a miles east of Ashburton and midway between the Ra aia and the Ashburton rivers. Average annual rainfall is 27 in., evenly spread, but there is very high summer evaporation and therefore frequent droughts. On average, the soil is below wilting point for 40 to 50 days each summer. Winters are cold with the soil temperature being below 48°F for about four months each year. The soil is a Lismore stony silt loam averaging 9 in. in depth over gravel.

Observations for the Role of Flux rope Eruption in a Geoeffective Solar Flare

2014 ◽  
Vol 4 (2) ◽  
pp. 555-564
Author(s):  
A.M Aslam
Keyword(s):  
Solar Flare ◽  
Flux Rope ◽  
Magnetic Configuration ◽  
Solar Dynamics Observatory ◽  
Multi Wavelength ◽  
Solar Dynamics ◽  
Halo Coronal Mass Ejection ◽  
Mass Ejection ◽  
The Waves

On September 24, 2011 a solar flare of M 7.1 class was released from the Sun. The flare was observed by most of the space and ground based observatories in various wavebands. We have carried out a study of this flare to understand its causes on Sun and impact on earth. The flare was released from NOAA active region AR 11302 at 12:33 UT. Although the region had already produced many M class flares and one X- class flare before this flare, the magnetic configuration was not relaxed and still continued to evolve as seen from HMI observations. From the Solar Dynamics Observatory (SDO) multi-wavelength (131 Ã…, 171 Ã…, 304 Ã… and 1600Ã…) observations we identified that a rapidly rising flux rope triggered the flare although HMI observations revealed that magnetic configuration did not undergo a much pronounced change. The flare was associated with a halo Coronal Mass Ejection (CME) as recorded by LASCO/SOHO Observations. The flare associated CME was effective in causing an intense geomagnetic storm with minimum Dst index -103 nT. A radio burst of type II was also recorded by the WAVES/WIND. In the present study attempt is made to study the nature of coupling between solar transients and geospace.

Role of Vasavaleha in the management of Covid19

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 259-261
Author(s):  
Aamir Khan ◽  
Rajni K. Gurmule
Keyword(s):  
Immune System ◽  
Human Body ◽  
Respiratory Diseases ◽  
Spreading Rate ◽  
Host Immune System ◽  
Shortness Of Breath ◽  
Antitussive Effect ◽  
Corona Viruses ◽  
Very High

Vasavaleha is one of the best medicine given for respiratory diseases. Corona viruses typically affect the respiratory system, causing symptoms such as coughing, fever and shortness of breath. It also affects host immune system of human body. Spreading rate of this disease is very high. Whole world is seeking for the treatment which can uproots this diseases. There in no vaccine available till date against this pandemic disease. Ayurveda mainly focuses on prevention of diseases alongwith its total cure. Rajyakshma Vyadhi is MadhyamMarga Roga as per Ayurveda. It shows many symptoms such as Kasa, Shwasa etc. By overall view of Covid 19, shows its resemblance with Rajyakshma Vyadhi described in Ayurveda. Vasavaleha is a Kalpa which is described in Rogadhikara of Rajyakshma. It shows Kasahara, Shwashara properties. It consists of Vasa, Pipalli, Madhu and Goghrita. These components shows actions like bronchodilation, antitussive effect and many more other actions. Pipalli shows important Rasayana effect. So in present review, we have tried to focus on role of Vasavaleha in the management of Covid 19. This can be used as preventive as well as adjuvant medication in treating Covid 19. There is need of further clinical research to rule of exact action of Vasavaleha against Covid 19.

EPIZOOTOLOGICAL FEATURES OF MODERN CATTLE LEUKEMIA

1970 ◽  
pp. 53-58
Author(s):  
V. V. Makarov ◽  
D. A. Lozovoy
Keyword(s):  
Dairy Cattle ◽  
Western Europe ◽  
Control Programs ◽  
Foreign Countries ◽  
Negative Order ◽  
Dairy Cattle Breeding ◽  
The Usa ◽  
Epizootic Process ◽  
National Programs

  Enzootic bovine leucosis (EBL) has been known for more than a century and a half. Its occurrence and registration may have historically been associated with intensive breeding of dairy cattle in Western Europe to increase target productivity. It is known that any limiting intervention in the nature of the animal organism is always accompanied by an uncontrolled and unpredictable change in the genotype of a wider range than the required, particularly negative order. In particular, a decrease in the resistance to macroorganisms and the possibility of the new diseases emergence, including infectious ones (for example, immunodeficiencies such as BLAD syndrome of black-motley cattle and stress syndrome in pigs, the occurrence of scrapie and other slow sheep infections). In the last two decades of the last century, in many disadvantaged countries, primarily Western European, national programs for the eradication of EBL have been developed and subsequently successfully implemented. First of all the motivation was the economy of dairy cattle breeding (mainly the extension of productive age, as well as the tightening of requirements in international trade in cattle and bull products, breeding, pricing, etc.). In an analytical article are reviewed the elements of epizootology of EBL in the foreign countries with special attention to the situation in the USA, scenarios of various control programs, and promising methods for assessing the role of infected animals in the epizootic process. A critical assessment of the problem of EBL in the Russian Federation is given, the reasons for the ineffectiveness of against leucosis measures are discussed.

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