scholarly journals Evaluation of the Combined Effect of Mobility and Seasonality on the COVID-19 Pandemic: A Lombardy-Based Study

2021 ◽  
Author(s):  
Yuri Falzone ◽  
Luca Bosco ◽  
Giacomo Sferruzza ◽  
Tommaso Russo ◽  
Marco Vabanesi ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Significant Role ◽  
Linear Models ◽  
Human Mobility ◽  
Additive Model ◽  
Environmental Variable ◽  
Environmental Data ◽  
Combined Effect ◽  
Uv Index ◽  
Non Linear

Abstract Restrictions to human mobility had a significant role in limiting SARS-CoV-2 spread. It has been suggested that seasonality might affect viral transmissibility. Our study retrospectively investigates the combined effect that seasonal environmental factors and human mobility played on transmissibility of SARS-CoV-2 in Lombardy, Italy, in 2020.Environmental data were collected from accredited open-source web services. Aggregated mobility data for different points of interests were collected from Google Community Reports. The Reproduction number (Rt), based on the weekly counts of confirmed symptomatic COVID-19, non-imported cases, was used as a proxy for SARS-CoV-2 transmissibility. Assuming a non-linear correlation between selected variables, we used a Generalized Additive Model (GAM) to investigate with univariate and multivariate analyses the association between seasonal environmental factors (UV-index, temperature, humidity, and atmospheric pressure), location-specific mobility indices, and Rt. UV-index was the most effective environmental variable in predicting Rt. An optimal two-week lag-effect between changes in explanatory variables and Rt was selected. The association between Rt variations and individually taken mobility indices differed: Grocery & Pharmacy, Transit Station and Workplaces displayed the best performances in predicting Rt when individually added to the multivariate model together with UV-index, accounting for 85.0%, 85.5% and 82.6% of Rt variance, respectively. According to our results, both seasonality and social interaction policies played a significant role in curbing the pandemic. Non-linear models including UV-index and location-specific mobility indices can predict a considerable amount of SARS-CoV-2 transmissibility in Lombardy during 2020, emphasizing the importance of social distancing policies to keep viral transmissibility under control, especially during colder months.

scholarly journals Associations between environmental covariates and malaria incidence in high transmission settings of Uganda: A distributed non-linear lagged ecological analysis

2021 ◽  
Author(s):  
Jaffer Okiring ◽  
Isobel Routledge ◽  
Adrienne Esptein ◽  
Jane F. Namuganga ◽  
Emmanuel V. Kamya ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Malaria Transmission ◽  
Malaria Incidence ◽  
Environmental Data ◽  
Environmental Covariates ◽  
High Transmission ◽  
Monthly Temperature ◽  
Rate Of Increase ◽  
Catchment Areas ◽  
Non Linear

Abstract Background Environmental factors such as temperature, rainfall, and vegetation cover play a critical role in malaria transmission. However, quantifying the relationships between environmental factors and measures of disease burden relevant for public health can be complex as effects are often non-linear and subject to temporal lags between when changes in environmental factors lead to changes in the incidence of symptomatic malaria. The study aim was to investigate the associations between environmental covariates and malaria incidence in high transmission settings of Uganda.Methods This study leveraged data from seven malaria reference centres (MRCs) located in high transmission settings of Uganda over a 24-month period (January 2019 - December 2020). Estimates of monthly malaria incidence (MI) were derived from MRCs’ catchment areas. Environmental data including monthy average measures of temperature, rainfall, and normalized difference vegetation index (NDVI) were obtained from remote sensing sources. A distributed non-linear lagged model was used to investigate the quantitative relationship between environmental covariates and malaria incidence. Results Overall, the median (range) monthly temperature was 30oC (26-47), rainfall 133.0 mm (3.0-247), NDVI 0.66 (0.24-0.80) and MI was 790 per 1000 person-years (73-3973). A non-linear relationship between environmental covariates and malaria incidence was observed. An average monthly temperature of 35oC was associated with significant increases in malaria incidence compared to the median observed temperature (30oC) at month lag 2 (IRR: 2.00, 95% CI: 1.42-2.83) and the cumulative increases in MI significantly at month lags 1-4, with the highest cumulative IRR of 8.16 (95% CI: 3.41-20.26) at lag month 4. An average monthly rainfall of 200mm was associated with significant increases in malaria incidence compared to the median observed rainfall (133mm) at lag month 0 (IRR: 1.24, 95% CI: 1.01-1.52) and the cumulative IRR increases of malaria at month lags 1-4, with the highest cumulative IRR of 1.99(95% CI: 1.22-2.27) at lag month 4. An average NVDI of 0.72 was associated with significant cumulative increases in IRR of malaria as compared to the median observed NDVI (0.66) at month lag 2-4, with the highest cumulative IRR of 1.57(95% CI: 1.09-2.25) at lag month 4. The rate of increase in cumulative IRR of malaria was highest within lag months 1-2 as compared to lag months 3-4 for all the environmental covariates.Conclusions In high-malaria transmission settings, high values of environmental covariates were associated with cumulative increases in the incidence of malaria, with peak associations occurring after variable lag times. The complex associations identified are valuable for designing strategies for early warning, prevention, and control of seasonal malaria surges and epidemics.

G Optimal Design in Non linear Models to Increase Silicon Oxide Purity Levels and Electrical Conductivity

2018 ◽  
pp. 150-155
Author(s):  
Muklas Rivai
Keyword(s):  
Electrical Conductivity ◽  
Optimal Design ◽  
Linear Models ◽  
Silicon Oxide ◽  
Information Matrix ◽  
Relevant Information ◽  
Non Linear

Optimal design is a design which required in determining the points of variable factors that would be attempted to optimize the relevant information so that fulfilled the desired criteria. The optimal fulfillment criteria based on the information matrix of the selected model.

scholarly journals 31.B. Workshop: Public health and urban design: an interdisciplinary approach to promote autism friendly environments

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
◽  
Keyword(s):  
Public Health ◽  
Risk Factors ◽  
Environmental Factors ◽  
Built Environment ◽  
Urban Design ◽  
Significant Role ◽  
Prevalence Rates ◽  
Environmental Characteristics ◽  
The Relationship

Abstract Autism is a set of heterogeneous neurodevelopmental conditions, characterised by early-onset difficulties in social communication and restricted, repetitive behaviour and interests. The worldwide population prevalence is about 1% with an increasing incidence and prevalence rates. Autism affects more male than female individuals, and comorbidity is common (>70% have concurrent conditions). Determinants of these changes in incidence and prevalence rates may also be related to exposure to environmental factors and to modifications in diagnostic concepts and criteria. In spite of the uncertainty in determinants of incidence of autisms, there is evidence that environmental characteristics play a significant role both as autism risk factors and as potential obstacles that influence the capabilities of autonomously and fully “using” everyday spaces. The workshop aims to provide a framework on risk factors of autism and explore the relationship with the built environment, focusing on the quality of the everyday spaces and projecting the effects that it could have in the long term on achieving a desirable level of quality of life. The 11th Sustainable Development Goals of United Nations “Make cities inclusive, safe, resilient and sustainable” underlines the necessity of designing policies and projects acting to enhance and promote healthy cities and communities by addressing the needs of the most vulnerable groups of inhabitants. Herewith we bring together the discipline of Public Health and Urban Design to promote an interdisciplinary debate on a little explored topic investigating how the approaches adopted during childhood to promote the wellbeing of people with ASD can be related or strengthen by focusing also on built environment design intervention to pursue and reach the same objectives even during adulthood. The workshop will consist of four presentations. The first focuses on giving an overview on current knowledge of intervention for people with autism, presenting also criteria for evidence-based interventions. The second explores the relationship between autism and built environment by providing an exhaustive framework of the available research literature in order to identify a first set of spatial requirements for autism friendly cities. The third examines the impact of built environment on ASD users with the aim of developing a specific evaluation tool for healthcare spaces and best practices formulation according to the specific sensorial hypo- or hyper-activation of people with autism. Finally, the fourth reports the results of a two years Research & Development project called “GAP REDUCE” finalized at developing an Assistive Technology tool to support people with ASD, adult and high-functioning, to plan urban itineraries towards daily destinations. Key messages World's incidence of autism is about 1% with an increasing incidence whose determining rates may also be related to environmental factors and to modifications in diagnostic concepts and criteria. Environmental characteristics play a significant role also as potential obstacles that influence the capabilities of people with autism of autonomously and fully “using” everyday spaces.

Modelling development ofCallosobruchus maculatusandAnisopteromalus calandraeat various constant temperatures using linear and non-linear models

2014 ◽  
Vol 24 (11) ◽  
pp. 1308-1320 ◽  
Author(s):  
M. Mobarakian ◽  
A.A. Zamani ◽  
J. Karmizadeh ◽  
N. Moeeny Naghadeh ◽  
M.S. Emami
Keyword(s):  
Linear Models ◽  
Non Linear

scholarly journals Early Detection of Defects through the Identification of Distortion Characteristics in Ultrasonic Responses

Mathematics ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 850
Author(s):  
Pietro Burrascano ◽  
Matteo Ciuffetti
Keyword(s):  
Early Detection ◽  
Additive Noise ◽  
Linear Models ◽  
High Stress ◽  
Damage Index ◽  
Hammerstein Model ◽  
Linear Behavior ◽  
Non Linear ◽  
Ultrasonic Techniques ◽  
Detection Of Defects

Ultrasonic techniques are widely used for the detection of defects in solid structures. They are mainly based on estimating the impulse response of the system and most often refer to linear models. High-stress conditions of the structures may reveal non-linear aspects of their behavior caused by even small defects due to ageing or previous severe loading: consequently, models suitable to identify the existence of a non-linear input-output characteristic of the system allow to improve the sensitivity of the detection procedure, making it possible to observe the onset of fatigue-induced cracks and/or defects by highlighting the early stages of their formation. This paper starts from an analysis of the characteristics of a damage index that has proved effective for the early detection of defects based on their non-linear behavior: it is based on the Hammerstein model of the non-linear physical system. The availability of this mathematical model makes it possible to derive from it a number of different global parameters, all of which are suitable for highlighting the onset of defects in the structure under examination, but whose characteristics can be very different from each other. In this work, an original damage index based on the same Hammerstein model is proposed. We report the results of several experiments showing that our proposed damage index has a much higher sensitivity even for small defects. Moreover, extensive tests conducted in the presence of different levels of additive noise show that the new proposed estimator adds to this sensitivity feature a better estimation stability in the presence of additive noise.

scholarly journals The impact of environmental variables on the spread of COVID-19 in the Republic of Korea

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yong Kwan Lim ◽  
Oh Joo Kweon ◽  
Hye Ryoun Kim ◽  
Tae-Hyoung Kim ◽  
Mi-Kyung Lee
Keyword(s):  
Environmental Factors ◽  
Virus Disease ◽  
Environmental Parameters ◽  
Environmental Data ◽  
Republic Of Korea ◽  
Metropolitan Region ◽  
Health Concern ◽  
Ozone Level ◽  
The Republic ◽  
The Impact

AbstractCorona virus disease 2019 (COVID-19) has been declared a global pandemic and is a major public health concern worldwide. In this study, we aimed to determine the role of environmental factors, such as climate and air pollutants, in the transmission of COVID-19 in the Republic of Korea. We collected epidemiological and environmental data from two regions of the Republic of Korea, namely Seoul metropolitan region (SMR) and Daegu-Gyeongbuk region (DGR) from February 2020 to July 2020. The data was then analyzed to identify correlations between each environmental factor with confirmed daily COVID-19 cases. Among the various environmental parameters, the duration of sunshine and ozone level were found to positively correlate with COVID-19 cases in both regions. However, the association of temperature variables with COVID-19 transmission revealed contradictory results when comparing the data from SMR and DGR. Moreover, statistical bias may have arisen due to an extensive epidemiological investigation and altered socio-behaviors that occurred in response to a COVID-19 outbreak. Nevertheless, our results suggest that various environmental factors may play a role in COVID-19 transmission.

Testing linear restrictions on non-linear models

1984 ◽  
Vol 15 (1-2) ◽  
pp. 91-96
Author(s):  
K.R. Sawyer ◽  
M.C. Rosalsky
Keyword(s):  
Linear Models ◽  
Non Linear ◽  
Linear Restrictions ◽  
Testing Linear
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