scholarly journals A logistic model for age-specific COVID-19 case-fatality rates

JAMIA Open ◽  
2020 ◽  
Vol 3 (2) ◽  
pp. 151-153
Author(s):  
Xiang Gao ◽  
Qunfeng Dong
Keyword(s):  
Mathematical Model ◽  
General Population ◽  
Logistic Model ◽  
Large Scale ◽  
Case Fatality ◽  
Rate Of Growth ◽  
Upper Limit

Abstract To develop a mathematical model to characterize age-specific case-fatality rates (CFR) of COVID-19. Based on 2 large-scale Chinese and Italian CFR data, a logistic model was derived to provide quantitative insight on the dynamics between CFR and age. We inferred that CFR increased faster in Italy than in China, as well as in females over males. In addition, while CFR increased with age, the rate of growth eventually slowed down, with a predicted theoretical upper limit for males (32%), females (21%), and the general population (23%). Our logistic model provided quantitative insight on the dynamics of CFR.

scholarly journals A Logistic Model for Age-Specific COVID-19 Case-Fatality Rates

2020 ◽  
Author(s):  
Xiang Gao ◽  
Qunfeng Dong
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
General Population ◽  
Logistic Model ◽  
Large Scale ◽  
Case Fatality ◽  
Published Data ◽  
Rate Of Growth ◽  
Upper Limit ◽  
Elder People

ABSTRACTObjectivesTo develop a mathematical model to characterize age-specific case-fatality rates (CFR) of COVID-19.Materials and MethodBased on two large-scale Chinese and Italian CFR data, a logistic model was derived to provide quantitative insight on the dynamics between CFR and age.Results and DiscussionWe inferred that CFR increased faster in Italy than in China, as well as in females over males. In addition, while CFR increased with age, the rate of growth eventually slowed down, with a predicted theoretical upper limit for males (32%), females (21%), and the general population (23%).ConclusionOur logistic model provided quantitative insight on the dynamics of CFR.Lay SummaryRecently published studies have qualitatively shown that the COVID-19 case-fatality rates increased with age, with elder people at higher risk of fatality than younger ones. In our study, we presented a quantitative mathematical modeling approach to re-analyze those published data. Specifically, we were able to derive a logistic model to characterize age-specific CFRs. The derived mathematical model uncovered novel quantitative insights on the dynamics between CFR and age. Specifically, we inferred from the model that while CFR increased with age, the rate of growth eventually slowed down, with a predicted theoretical upper limit of 23% for the general population.

scholarly journals Mental health and caregiving experiences of family carers supporting people with psychosis

2021 ◽  
Vol 30 ◽  
Author(s):  
J. Sin ◽  
J. Elkes ◽  
R. Batchelor ◽  
C. Henderson ◽  
S. Gillard ◽  
...  
Keyword(s):  
Mental Health ◽  
Risk Factors ◽  
General Population ◽  
Large Scale ◽  
Controlled Trial ◽  
Population Sample ◽  
Poor Mental Health ◽  
Mental Wellbeing ◽  
Family Carers ◽  
Negative Experience

Abstract Aims Family carers supporting an individual with psychosis often experience poorer mental health, however, little is known about specific risk factors among these carers. We investigated the associations between demographic, caregiving characteristics and mental health outcomes in family carers supporting an individual with psychosis and compared carers' outcomes with general population norms. Methods We analysed baseline data from the COPe-support randomised controlled trial of online psychoeducation and peer support for adult carers supporting an individual with psychosis between 2018 and 2020. We collected carers' demographic and health outcome data, including wellbeing using Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS as primary outcome), quality of life using EQ-5D-5L and caregiving experience assessed with Experience of Caregiving Inventory. We tested associations between carers' demographic and caregiving characteristics for each outcome in turn and meta-analysed carers' WEMWBS and EQ-5D-5L with Health Survey England (HSE) general population data from 2016 and 2017, respectively. Results The 407 carers of people with psychosis had a mean WEMWBS score of 42.2 (s.d. 9.21) and their overall weighted pooled WEMWBS score was 7.3 (95% confidence interval (CI) −8.6 to −6.0, p < 0.01) lower than the HSE general population sample, indicating carers have poorer mental wellbeing by more than double the minimum clinically important difference of 3 points on WEMWBS. Among all caring relationships, partners had poorer wellbeing compared to parents with lower WEMWBS score (−6.8, −16.9 to 3.3, p = 0.03). Single carers had significantly poorer wellbeing (−3.6, −5.6 to −1.5, p < 0.01) and a more negative caregiving experience than those who were cohabiting. Spending more than 35 h per week caregiving increased carers' negative experience significantly (p = 0.01). Conclusion Carers of people with psychosis have poorer mental health than non-carers. Partners, lone carers and those spending more than 35 h per week on caring were found to be most at risk of poor mental health. Based on the results, we advocate that the details of carers for individuals with psychosis should be added to the existing carers or severe mental illness registers at all general practitioner surgeries and for their wellbeing screened routinely. Future large-scale prospective studies are needed to develop a predictive model to determine risk factors, hence to aid early identification of carers' support needs. Such understandings are also useful to inform tailored intervention development.

Grey Logistic Model to Predict the Effective Irrigation Area in Liaoning Province

2014 ◽  
Vol 641-642 ◽  
pp. 179-182 ◽  
Author(s):  
Jin Liang Chen
Keyword(s):  
Logistic Model ◽  
Structural Adjustment ◽  
Logistic Equation ◽  
Liaoning Province ◽  
Forecasting Model ◽  
Irrigation Area ◽  
Agricultural Resources ◽  
Upper Limit ◽  
Simulation Results ◽  
Good Agreement

Through grey estimation of the parameters of logistic equation, a grey logistic forecasting model is established. The effective irrigation area in Liaoning Province was simulated by the model. The simulation results had good agreement with the available data, with a correlation of 0.95. The effective irrigation area was predicted to be 1.583 million hectares in 2018, very close to the predicted upper limit of 1.588 million hectares. Thus, there is little potential for the development of the effective irrigation area, rendering the structural adjustment of agricultural resources very necessary.

scholarly journals Immune defects and cardiovascular risk in X chromosome monosomy mosaicism mediated by loss of chromosome Y. A risk factor for SARS-CoV-2 vulnerability in elderly men?

2020 ◽  
Author(s):  
Luis A. Pérez-Jurado ◽  
Alejandro Cáceres ◽  
Tonu Esko ◽  
Juan R. González
Keyword(s):  
Cardiovascular Risk ◽  
X Chromosome ◽  
Large Scale ◽  
Case Fatality ◽  
Peripheral Blood Cell ◽  
Coagulation Activity ◽  
Chromosome Y ◽  
Immune System Dysfunction ◽  
Cell Counts ◽  
Multiple Biomarkers

AbstractThe ongoing pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) has an estimated overall case fatality ratio of 1.38% in China, being 53% higher in males and increasing exponentially with age. Mosaicism for X chromosome monosomy (XCM) shows a similar increase in aging population mostly driven by loss of chromosome Y in males (LOY), and is associated with a raise in all-cause mortality. Using comparative transcriptomic data, we have defined that XCM/LOY is associated with abnormal peripheral blood cell counts with decreased progenitor cells and multiple biomarkers of immune system dysfunction, pro-coagulation activity and increased cardiovascular risk. Several differentially down-regulated genes in XCM/LOY individuals are involved in the initial immune response to SARS-CoV-2 (OR of enrichment=7.23, p=1.5×10−7), mainly interferon-induced genes that code for inhibitors of viral processes. Thus, our data suggest that XCM mosaicism underlies at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential relevance for modulating prognosis and therapeutic response, we propose that evaluation of LOY and XCM by currently established methods should be implemented as biomarkers in infected patients, including currently ongoing clinical trials with different medications and vaccines for COVID-19. Testing for LOY/XCM at large scale among elderly people may also be helpful to identify still unexposed people who may be especially vulnerable to severe Covid-19 disease.

scholarly journals The seasonality of cholera in sub-Saharan Africa

2021 ◽  
Author(s):  
Javier Perez-Saez ◽  
Justin Lessler ◽  
Elizabeth C. Lee ◽  
Francisco J. Luquero ◽  
Espoir B. Malembaka ◽  
...  
Keyword(s):  
Large Scale ◽  
Task Force ◽  
Case Fatality ◽  
Sub Saharan Africa ◽  
Health Concern ◽  
National Differences ◽  
Sub Saharan ◽  
Eastern And Southern Africa ◽  
Positive Correlations ◽  
Gates Foundation

Background Cholera remains a major threat in Sub-Saharan Africa (SSA) where some of the highest case fatality risks are reported. Knowing in what months and where cholera tends to occur across the continent can aid in improving efforts to eliminate cholera as a public health concern; though largely due to lack of unified large-scale datasets, no continent-wide estimates exist. In this study we aim to estimate cholera seasonality across SSA. Methods We leverage the Global Task Force on Cholera Control (GTFCC) global cholera database with statistical models to synthesize data across spatial and temporal scale in order to infer the seasonality of excess suspected cholera occurrence in SSA. We developed a Bayesian statistical model to infer the monthly risk of excess cholera at the first and/or second administrative levels. Seasonality patterns were then grouped into spatial clusters. Finally, we studied the association between seasonality estimates and hydro-climatic variables. Findings The majority of studied countries (24/34) have seasonal patterns in excess cholera, corresponding to approximately 85% of the SSA population. Most countries (19/24) also had sub-national differences in seasonality patterns, with strong differences in seasonality strength between regions. Seasonality patterns clustered into two macro-regions (West Africa and the Sahel vs. Eastern and Southern Africa), which were composed of sub-regional clusters with varying degrees of seasonality. Exploratory association analysis found most consistent and positive correlations between cholera seasonality and precipitation, and to a lesser extent with temperature and flooding. Interpretation Widespread cholera seasonality in SSA offers opportunities for intervention planning. Further studies are needed to study the association between cholera and climate. Funding The NASA Applied Sciences Program and the Bill and Melinda Gates Foundation.

scholarly journals Contrasting SARS-CoV-2 epidemics in Singapore: Cohort studies in migrant workers and the general population

2021 ◽  
Author(s):  
Hannah E Clapham ◽  
Wan Ni Chia ◽  
Linda Wei Lin Tan ◽  
Vishakha Kumar ◽  
Jane M Lim ◽  
...  
Keyword(s):  
General Population ◽  
Cohort Studies ◽  
Migrant Workers ◽  
Large Scale ◽  
Migrant Worker ◽  
Community Dwelling ◽  
Control Measures ◽  
Preparedness Planning ◽  
Community Transmission

Abstract From January 2020, Singapore implemented comprehensive measures to suppress SARS-CoV-2. Community transmission has been limited, although explosive outbreaks have occurred in migrant worker dormitories. We conducted longitudinal SARS-CoV-2 serology studies among 478 residents of a SARS-CoV-2 affected migrant worker dormitory between May and July 2020, and 937 community-dwelling adult Singapore residents with sera collected before September 2019 and in November/December 2020. By end 2020, <2 per 1000 (0.16%, 95% CrI: 0.008% - 0.72%) adult residents in the community were infected with SARS-CoV-2, approximately 4 times higher than the national notified case incidence. In contrast, in the migrant worker cohort, nearly two-thirds 63.8% (95% CrI: 57.9% - 70.3%) had been infected by July 2020; no symptoms were reported in >90% of these infections. SARS-CoV-2 suppression is feasible with rapid implementation of comprehensive control measures. However, the risk of large-scale epidemics in densely-populated environments requires specific consideration in preparedness planning.

Traffic Fuzzy Controller's Improvement Based on Self-Adaptive Optimal Algorithm

2012 ◽  
Vol 562-564 ◽  
pp. 1414-1417
Author(s):  
Zhi Yi Xu ◽  
Da Lu Guan ◽  
Ai Long Fan
Keyword(s):  
Mathematical Model ◽  
Large Scale ◽  
Fuzzy Controller ◽  
Optimal Algorithm ◽  
Signal Control ◽  
Traffic Signal Control ◽  
Time Varying ◽  
Large Scale Systems ◽  
Simulation Results ◽  
Self Adaptive

The transport system is a nonlinear, time-varying, lagging large-scale systems. Fuzzy control does not need to build a precise mathematical model, can be easily integrated people's thinking and experience, and is suitable for applications in the traffic signal control system. Here,a self-adaptive optimal algorithm was used to improve the traditional fuzzy controller. Simulation results show that the improved system has higher availability.

Tsunamis

2017 ◽  
Author(s):  
John A. Adam
Keyword(s):  
Mathematical Model ◽  
Large Scale ◽  
Volcanic Eruptions ◽  
Ocean Waves ◽  
The Other ◽  
Tsunami Generation ◽  
Sea Waves ◽  
Tsunami Propagation ◽  
Tidal Waves ◽  
Special Cases

This chapter describes a mathematical model of tsunami propagation (transient waves). A tsunami is a series of ocean waves triggered by large-scale disturbances of the ocean, including earthquakes, as well as landslides, volcanic eruptions, and meteorites. Tsunamis have very long wavelengths (typically hundreds of kilometers). They have also been called “tidal waves” or “seismic sea waves,” but both terms are misleading. The chapter first considers the boundary-value problem before modeling two special cases of tsunami generation, one due to an initial displacement on the free surface and the other due to tilting of the seafloor. It also discusses surface waves on deep water and how fast the wave energy propagates and concludes with an analysis of leading waves due to a transient disturbance.

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