scholarly journals Prediction of COVID-19 pandemic dynamics in Russia based on simple mathematical models of epidemics

2021 ◽  
pp. 31-41
Author(s):  
Dmitry Tomchin ◽  
Maria Sitchikhina ◽  
Mikhail Ananyevskiy ◽  
Tatyana Sventsitskaya ◽  
Alexander Fradkov
Keyword(s):  
Least Squares Method ◽  
Published Data ◽  
Individual Country ◽  
Incidence Data ◽  
Urgent Task ◽  
Fast Processing ◽  
Morbidity Data ◽  
Official Data ◽  
Scenario Approach ◽  
Simple Models

Introduction: The COVID-19 pandemic which began in 2020 and has taken more than five million lives has become a threat to the very existence of mankind. Therefore, predicting the spread of COVID-19 in each individual country is a very urgent task. The complexity of its solution is due to the requirement for fast processing of large amounts of data and the fact that the data are mostly inaccurate and do not have the statistical properties necessary for the successful application of statistical methods. Therefore, it seems important to develop simple forecasting methods based on classical simple models of epidemiology which are only weakly sensitive to data inaccuracies. It is also important to demonstrate the feasibility of the approach in relation to the incidence data in Russia. Purpose: Obtaining forecast data based on classical simple models of epidemics, namely SIR and SEIR. Methods: For discrete versions of SIR and SEIR models, it is proposed to estimate the parameters of the models using a reduced version of the least squares method, and apply a scenario approach to the forecasting. The simplicity and a small number of parameters are the advantages of SIR and SEIR models, which is very important in the context of a lack of numerical input data and structural incompleteness of the models. Results: A forecast of the spread of COVID-19 in Russia has been built based on published data on the incidence from March 10 to April 20, 2020, and then, selectively, according to October 2020 data and October 2021 data. The results of the comparison between SIR and SEIR forecasts are presented. The same method was used to construct and present forecasts based on morbidity data in the fall of 2020 and in the fall of 2021 for Russia and for St. Petersburg. To set the parameters of the models which are difficult to determine from the official data, a scenario approach is used: the dynamics of the epidemic is analyzed for several possible values of the parameters. Practical relevance: The results obtained show that the proposed method predicts well the time of the onset of the peak incidence, despite the inaccuracy of the initial data.

Averaging and Simple Models

1996 ◽  
Author(s):  
Ilya Polyak
Keyword(s):  
Least Squares ◽  
Least Squares Method ◽  
Correlation Structure ◽  
Correlated Observations ◽  
Dependent Observations ◽  
Basic Assumptions ◽  
Temporal Averaging ◽  
Meteorological Observations ◽  
Simple Models

Simple linear procedures for processing correlated observations are considered and interpreted in this chapter. Primarily, they present different schemes for averaging data. These procedures are important because climatology has historically dealt with spatial and temporal averaging of statistically dependent meteorological observations. The accuracy of such averaging is determined by the volume of data arid by its correlation structure. The examples presented in this chapter illustrate the level of accuracy that can be achieved within the framework of some assumptions about such correlation structure. Let us consider the principal relationships of the least squares method for the statistically dependent observations (see Rao, 1973). The basic assumptions are as follows.

scholarly journals A Synoptic Analysis of the Temporal and Spatial Aspects of Grapevine Leafroll Disease in a Historic Napa Vineyard and Experimental Vine Blocks

2017 ◽  
Vol 107 (4) ◽  
pp. 418-426 ◽  
Author(s):  
K. Arnold ◽  
D. A. Golino ◽  
N. McRoberts
Keyword(s):  
Disease Incidence ◽  
Published Data ◽  
Effective Sample Size ◽  
Data Sets ◽  
Distribution Fitting ◽  
Incidence Data ◽  
Napa Valley ◽  
Temporal And Spatial ◽  
Low Incidence ◽  
High Degree

Five Grapevine leafroll-associated virus 3 (GLRaV-3) epidemics were analyzed utilizing a standardized approach to robustly characterize the temporal and spatial parameters. Published data included in the analysis are from Spain, New Zealand, and Napa Valley, CA together with new data from a historic vineyard in Napa Valley, CA. Linear regression analyses of logit-transformed incidence data indicated a maximum average increase of 11% per year in disease incidence, with considerable variation among locations. Spatial analyses, including distribution fitting, examination of the effective sample size, and evaluation of the parameters of the binary power law fitted to variance data for disease incidence, indicated a high degree of consistency among the data sets. In all cases, except at very low disease incidence, a high degree of spatial aggregation was noted, with evidence that the degree of aggregation varied as a function of mean disease incidence. The polyetic dynamics of disease follow a logistic-like pattern over multiple seasons, consistent with limitation by inoculum availability (infected vines) at low incidence and limitation by disease-free vines at high incidence.

Health care costs of comorbidities in patients with HIV infection in Italy. An estimate using a Delphi panel

2006 ◽  
Vol 7 (1) ◽  
pp. 37-43
Author(s):  
Carlo Lucioni ◽  
Silvio Mazzi ◽  
Giuliano Bensi
Keyword(s):  
Hospital Admissions ◽  
Opportunistic Infections ◽  
Delphi Panel ◽  
Published Data ◽  
Co Morbidity ◽  
Morbidity Data ◽  
One Year ◽  
Care Costs ◽  
Immunologic Status

In HIV affected patients, co-morbidities (also termed opportunistic infections or AIDS-defining events) characterise the disease progression, resulting from deteriorating immunologic status. They are the commonest cause of morbidity and mortality among such patients and may account for a major share of the overall health cost of HIV. Given the paucity of published data about co-morbidities costs in Italy, an estimation was targeted and then reached using a Delphi panel. A questionnaire, the same for each of the 22 co-morbidities considered, was designed where type and quantity of resources used (which and how many lab tests, hospital admissions, drugs) were to be reported concerning three steps (diagnosis, acute treatment, follow-up within one year) in each comorbidity. Six experts, belonging to as many infectious diseases centres located all over Italy, were involved to independently complete the questionnaires. Information about resources in physical terms, collected from the first round of the panel, was converted into monetary terms, aggregated (a cost for each co-morbidity was estimated averaging the corresponding six costs deriving from the centres), and sent back to the experts. Each expert received also the costs per co-morbidity data as resulting from the others’ answers (though in anonymous form) and was invited to confirm or revise the answers he had previously given. The same processing was then performed when information was available from the second round. A substantial convergence among the final data from the different experts came into evidence. According to this Delphi panel results, the overall average cost for a HIV co-morbidity in Italy is 8,967 euros; the most expensive co-morbidity is CMV retinitis (27,946 euros) and the cheapest is herpes simplex (2,057 euros).

Incidence of nasopharyngeal carcinoma in Chinese immigrants, compared with Chinese in China and South East Asia: review

2009 ◽  
Vol 123 (10) ◽  
pp. 1067-1074 ◽  
Author(s):  
W M Yu ◽  
S S M Hussain
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Medical Profession ◽  
Incidence Rates ◽  
Background Information ◽  
Published Data ◽  
Chinese People ◽  
Raw Data ◽  
Hand Search ◽  
Chinese Populations ◽  
Incidence Data

AbstractObjectives:To evaluate the literature and to compare published data on age-standardised incidence rates of nasopharyngeal carcinoma in Chinese people living in and outside China.Design:Systematic review of incidence rate studies and statistical incidence data concerning nasopharyngeal carcinoma in Chinese populations from 1960 to 2008.Data sources:Sixteen papers were identified from the PubMed, Embase and Scopus electronic databases and from a hand search of the reference lists of the retrieved papers. Further searches for raw data on age-specific and age-standardised incidence rates of nasopharyngeal carcinoma were conducted. Textbooks on relevant subjects were referred to for background information. A total of 19 papers met the inclusion criteria.Results:Seven studies included raw data on age-specific and age-standardised incidence rates of nasopharyngeal carcinoma in Chinese people. Twelve other studies reported on changes in the incidence of nasopharyngeal carcinoma in Chinese populations in selected countries or regions. Studies on age-specific and age-standardised rates obtained data from individual registries. Studies on incidence rates obtained data from hospital records, cancer notifications (from all sections of the medical profession), pathology records and death certificates. The results showed a decline in age-standardised incidence rates of nasopharyngeal carcinoma in Chinese immigrant populations, compared with Chinese people in China. There was also a trend towards decreasing incidence the further the population had immigrated. Thus, the incidence of nasopharyngeal carcinoma in Singaporean Chinese was higher than that in Hawaiian Chinese, and that in Hawaiian Chinese was higher than that in Californian Chinese.Conclusion:This review found a decreasing trend in the incidence of nasopharyngeal carcinoma in Chinese migrants living in countries with a low risk of the disease.

scholarly journals Analysis and Forecasting Electricity Production of Kyrgyzstan by the Method of Least Squares

2021 ◽  
Vol 7 (5) ◽  
pp. 322-326
Keyword(s):  
Least Squares ◽  
Energy Supply ◽  
Least Squares Method ◽  
Energy Resource ◽  
Electric Power Industry ◽  
Electricity Production ◽  
Method Of Least Squares ◽  
Natural Energy ◽  
Urgent Task ◽  
The Republic

The object of research in this article is the electric power industry of Kyrgyzstan. Each country strives to have its own energy at the lowest price in comparison with other regions or countries, making the most of its regional natural energy resource. In the republic, the main energy resource is hydropower resources. Forecasting energy supply in Kyrgyzstan is an urgent task. The article examines the analysis of electricity production in Kyrgyzstan by the least squares method and shows that the provision of electricity production is highly dependent on electricity production rather than the price and demand for it.

scholarly journals Consumption of Anti-Epileptic Drugs in Primary Health Care in Albania, 2004-2016

2019 ◽  
Vol 7 (15) ◽  
pp. 2545-2550
Author(s):  
Laerta Kakariqi ◽  
Gentian Vyshka
Keyword(s):  
International Comparisons ◽  
Defined Daily Dose ◽  
Primary Health ◽  
Parallel Increase ◽  
Consumption Data ◽  
Daily Dose ◽  
Morbidity Data ◽  
New Generation ◽  
Utilisation Data ◽  
Official Data

BACKGROUND: Epilepsy is a serious neurological condition requiring sometimes lifelong pharmacological treatment, and continuous specialist monitoring. AIM: To investigate the use of Anti-Epileptic Drugs (AEDs) in epilepsy, with focus on the exposure of AEDs, differences and changes in prescription patterns over time; to evaluate the relation between the consumption data of AED and the level of epileptic morbidity for the period 2004-2016. STUDY DESIGN: Official data regarding the consumption of AEDs within Albania were collected retrospectively. Every year of the period, 2004-2016 has been considered separately. METHODS: The data were assembled from Health Insurance Institute (HII) in Tirana, Albania and analysed for the period 2004-2016. The consumption of drugs was expressed as several Defined Daily Dose (DDDs)/1000 inhabitants/day. Also, for all the period under study 2004-2016, we analysed the data of import and domestic production of drugs, which represent the real consumption of drugs in the country. These data were subsequently involved in a comparative analysis with the utilisation data according to the HII, as well as through performing international comparisons of the consumption of AEDs drugs. RESULTS: Epilepsy morbidity data indicate that there exists a correlation statistically significant between this disease and the trend of consumption of AEDs. CONCLUSION: The present study suggests that the level of consumption for AEDs in Albania is very low when compared globally; with a decrease in the consumption of classic antiepileptic drugs and a parallel increase in the consumption of new generation drugs.

scholarly journals Successive waves of COVID 19: confinement effects on virus-prevalence with a mathematical model

2021 ◽  
Vol 26 (1) ◽  
Author(s):  
S. Abdalla ◽  
Duaa Bakhshwin ◽  
W. Shirbeeny ◽  
Ahmed Bakhshwin ◽  
F. Bahabri ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Decision Maker ◽  
Total Population ◽  
Published Data ◽  
Maximum Point ◽  
Worst Case ◽  
Incidence Data ◽  
Reproduction Numbers ◽  
The Social ◽  
The Usa

Abstract Background A pandemic outbreak of severe acute respiratory syndrome coronavirus 2 (COVID 19) incidence data are largely available online. Until August 17, COVID 19 has hit more than 22 million individuals all over the globe. So, it is urged to get clear information about the prevalence of the virus. Therefore, one can manipulate easily a suitable mathematical model to fit these published data. Methods We propose a mathematical model that considers the total population, in 25 countries, either infected by COVID 19 or confined (safe) during the period from November 17, 2019, to August 17, 2020. The model considers the total population as a complex number; the imaginary part is the number of infected individuals and the real part is the number of confined individuals. This classification combined with mathematical treatments leads to a transmission dynamics of the virus to be as wave-like motion. The virus can hit any country either by one wave or by successive waves (up to 11 waves). Findings We find net discrimination between the 25 countries investigated in this report. The immediate response to the first attack is a substantial parameter to determine whether the epidemic attack will be in one wave or it can be in successive waves. For example, the best case was such as individuals in China hit by one wave while the individuals in the USA were attacked by nine waves; it is the worst case all over the globe. In addition, the model differentiates between the daily reproduction numbers (Rd0) and the median reproduction number (R0). We have found that Rd0 decreases exponentially with time from high values down to zero at the wave maximum point; and R0 varies from a country to another. For example, the virus hit individuals in Germany in R0 = 1.39 (96% CI 1.01–3.87) and in the USA R0 = 3.81 (91% CI 1.71–5.15). We have found that twice the virus has hit both the USA and Iran. The great protestation of black matter lives in the USA and the great assemblage of the new Iranian year, on March 21, 2020, have been the cause of the second epidemic attack in both countries. Interpretation Our results show that COVID 19 transmission depends on the prompt reaction against the first viral-wave. The reaction depends on both the social behaviour of individuals and on the swift system-decision by the governmental decision-maker(s). The Chinese strictly follow the decision-maker and therefore the virus hit by only one wave; while in the USA, the system-decision was different and the American-responses were different, therefore ten waves followed the first wave.

scholarly journals Assessment of significant for breeding morphological traits in the double haploid population of Brassica rapa L. in controlled conditions of a regulated agroecosystem

2020 ◽  
pp. 28-31
Author(s):  
K. V. Egorova ◽  
N. G. Sinyavina ◽  
A. A. Kochetov ◽  
Yu. V. Chesnokov
Keyword(s):  
Genetic Selection ◽  
Morphological Characteristics ◽  
Environmental Parameters ◽  
Published Data ◽  
Forage Crops ◽  
Controlled Conditions ◽  
Environmental Light ◽  
Urgent Task ◽  
Economically Valuable Traits ◽  
Mapping Populations

Relevance. The genus Brassica includes the most important vegetable, oilseed, spice and forage crops. Many representatives of cabbage are widely used as model objects for studying economically valuable traits. Limited publications devoted to the study of genetic aspects of the implementation of morphological quantitative features of B. rapaand the lack of data on the influence of environmental parameters on their implementation make it a very urgent task to study these features in the RAES. Material and methods.The purpose of this work is to study the influence of environmental light factors on the manifestation of economically valuable features in the mapping populations of B. rapain the RAES. The peculiarity of our research is the study of lines of mapping populations of B. rapa in strictly controlled conditions of the RAES. The studied populations were grown under optimal conditions with a 12-hour photoperiod. 21 DH 30 lines and 31 DH 38 lines were used. Several types of economically valuable traits were studied: the timing of transition to flowering, the growth rate of the plant, the habit and morphological characteristics of the leaf and leaf rosette. Results. A high degree of variation in the expression of the studied traits between lines within the population was revealed, which is consistent with previously published data [1, 2]. Highly productive genotypes, which can be used in further genetic selection work, including for obtaining genotypes, lines, and varieties adapted for growing in light culture, have been selected. The obtained data can also be used for further study of the influence of physical environmental factors on the manifestation of selectively significant quantitative traits in cabbage plants. 

scholarly journals Research on the segments performance of the innovative startups ecosystem in the Russian Federation

Upravlenie ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 127-139
Author(s):  
B. E. Tokarev
Keyword(s):  
Telephone Survey ◽  
The Internet ◽  
Published Data ◽  
Secondary Sources ◽  
The World ◽  
Quantitative Characteristics ◽  
The Russian Federation ◽  
Term Performance ◽  
Official Data

With the determination of the number of new innovative startups businesses, the situation is even more complicated, not only in our country, but also in most countries of the world. In the proposed work, the author made an attempt to implement one of the possible approaches to introducing transparency – an assessment of each of the segments of the startup-launches ecosystem separately. The paper gives the results of study on the evaluation the launch indicators of new startups in the Russian venture market. The article identifies the segments of the venture ecosystem that are directly involved in the launch of new startups. The study obtained an estimate of the number of startups, small and medium-sized companies as well as entrepreneurial startups. To characterize the number of new startups, the author introduces the term performance of segments of the ecosystem of innovative startups. This indicator allows you to use the quantitative characteristics of individual segments and compare them with each other. To obtain quantitative values of newly launched startups, the author conducted a selective telephone survey of representatives of these segments of the ecosystem and collected official data published on the Internet. The author carried out the processing of some data on the basis of the statistics of median values of the estimate of the number of new startups that started sales during 2019. The author collected data for 2020 from secondary sources. The study showed that 4,817 new startups with signs of innovation were launched in Russia in 2020, and an increase of 26 % compared to the previous year. The estimates obtained do not contradict with the published data on the state of the venture industry during the pandemic.

scholarly journals Taxonomic Catalog of the Brazilian Fauna: order Trichoptera (Insecta), diversity and distribution

2020 ◽  
Vol 37 ◽  
pp. 1-13
Author(s):  
Allan P.M. Santos ◽  
Leandro L. Dumas ◽  
Ana L. Henriques-Oliveira ◽  
W. Rafael M. Souza ◽  
Lucas M. Camargos ◽  
...  
Keyword(s):  
Atlantic Forest ◽  
Federal District ◽  
Neotropical Region ◽  
Bootstrap Support ◽  
Published Data ◽  
Amazon Forest ◽  
South American ◽  
Incidence Data ◽  
On Line ◽  
Hydrographic Regions

Caddisflies are a highly diverse group of aquatic insects, particularly in the Neotropical region where there is a high number of endemic taxa. Based on taxonomic contributions published until August 2019, a total of 796 caddisfly species have been recorded from Brazil. Taxonomic data about Brazilian caddisflies are currently open access at the “Catálogo Taxonômico da Fauna do Brasil” website (CTFB), an on-line database with taxonomic information on the animal species occurring in Brazil. The order Trichoptera at CTFB includes a catalog of species recorded for the country, with synonymic lists, distribution throughout six biomes, 12 hydrographic regions, and 27 political states (including Federal District) from Brazil. The database is constantly updated to include newly published data. In this study, we reviewed the taxonomic effort on Brazilian caddisflies based on data currently in CTFB database. The accumulation curve of species described or recorded from the country, by year, shows a strong upward trend in last 25 years, indicating that it is possible that there are many more species to be described. Based on presence/absence of caddisfly species at three geographic levels (biomes, hydrographic regions, and states), second order Jackknife estimated at least 1,586 species occurring in Brazil (with hydrographic regions as unities), indicating we currently know about 50% of the Brazilian caddisfly fauna. Species distribution by Brazilian biomes reveals that the Atlantic Forest is the most diverse, with 490 species (298 endemic), followed by the Amazon Forest, with 255 species (101 endemic). Even though these numbers may be biased because there has been more intense collecting in these two biomes, the percentage of endemic caddisfly species in the Atlantic Forest is remarkable. Considering the distribution throughout hydrographic regions, clustering analyses (UPGMA) based on incidence data reveals two groups: northwestern basins and southeastern. Although these groups have weak bootstrap support and low similarity in species composition, this division of Brazilian caddisfly fauna could be related to Amazon-Atlantic Forest disjunction, with the South American dry diagonal acting as a potential barrier throughout evolutionary time.

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