scholarly journals A class of identifiable birth-death models

2021 ◽  
Author(s):  
Brandon Legried ◽  
Jonathan Terhorst
Keyword(s):  
Large Class ◽  
Death Rate ◽  
Regularity Conditions ◽  
Piecewise Constant ◽  
Striking Result ◽  
Global Pandemic ◽  
Rate Functions ◽  
Infinite Collection ◽  
Phylodynamic Analysis ◽  
Birth Death

In a striking result, Louca and Pennell (2020) recently proved that a large class of birth-death models are statistically unidentifiable from lineage-through-time (LTT) data. Specifically, they showed that any pair of sufficiently smooth birth and death rate functions is "congruent" to an infinite collection of other rate functions, all of which have the same likelihood for any LTT vector of any dimension. This fact has distressing implications for the thousands of studies which have utilized birth-death models to study evolution. In this paper, we qualify their finding by proving that an alternative and widely used class of birth-death models is indeed identifiable. Specifically, we show that piecewise constant birth-death models can, in principle, be consistently estimated and distinguished from one another, given a sufficiently large extant time tree and some knowledge of the present day population. Subject to mild regularity conditions, we further show that any unidentifiable birth-death model class can be arbitrarily closely approximated by a class of identifiable models. The sampling requirements needed for our results to hold are explicit, and are expected to be satisfied in many contexts such as the phylodynamic analysis of a global pandemic.

Analytic-Thinking Predicts Hoax Beliefs and Helping Behaviors in Response to the COVID-19 Pandemic

2020 ◽  
Author(s):  
Matthew Stanley ◽  
Paul Seli ◽  
Nathaniel Barr ◽  
KELLY PETERS
Keyword(s):  
Public Health ◽  
Cognitive Processes ◽  
Death Rate ◽  
The United States ◽  
Public Health Emergency ◽  
Hand Washing ◽  
Analytic Thinking ◽  
Social Distancing ◽  
Change Behavior ◽  
Global Pandemic

The coronavirus (COVID-19) outbreak was labeled a global pandemic by the WHO in March of 2020. During that same month, the number of confirmed cases and the death rate grew exponentially in the United States, creating a serious public-health emergency. Unfortunately, many Americans dismissed the pandemic as a hoax and failed to properly engage in helpful behaviors like social-distancing and increased hand-washing. Here, we examine a disposition—willingness to engage in analytic-thinking—that might predict beliefs that the pandemic is a hoax and failures to change behavior in positive ways. Our results indicate that individuals less willing to engage effortful, deliberative, and reflective cognitive processes were more likely to believe the pandemic was a hoax, and less likely to have recently engaged in social-distancing and hand-washing. We discuss the implications of these results for understanding and addressing the COVID-19 pandemic.

Analytic-Thinking Predicts Hoax Beliefs and Helping Behaviors in Response to the COVID-19 Pandemic

2020 ◽  
Author(s):  
Matthew Stanley ◽  
Nathaniel Barr ◽  
KELLY PETERS ◽  
Paul Seli
Keyword(s):  
Public Health ◽  
Cognitive Processes ◽  
Death Rate ◽  
The United States ◽  
Public Health Emergency ◽  
Hand Washing ◽  
Analytic Thinking ◽  
Social Distancing ◽  
Change Behavior ◽  
Global Pandemic

The coronavirus (COVID-19) outbreak was labeled a global pandemic by the WHO in March of 2020. During that same month, the number of confirmed cases and the death rate grew exponentially in the United States, creating a serious public-health emergency. Unfortunately, many Americans dismissed the pandemic as a hoax and failed to properly engage in helpful behaviors like social-distancing and increased hand-washing. Here, we examine a disposition—willingness to engage in analytic-thinking—that might predict beliefs that the pandemic is a hoax and failures to change behavior in positive ways. Our results indicate that individuals less willing to engage effortful, deliberative, and reflective cognitive processes were more likely to believe the pandemic was a hoax, and less likely to have recently engaged in social-distancing and hand-washing. We discuss the implications of these results for understanding and addressing the COVID-19 pandemic.

scholarly journals Families of birth-death processes with similar time-dependent behaviour

2000 ◽  
Vol 37 (03) ◽  
pp. 835-849 ◽  
Author(s):  
R. B. Lenin ◽  
P. R. Parthasarathy ◽  
W. R. W. Scheinhardt ◽  
E. A. van Doorn
Keyword(s):  
Death Rate ◽  
General Setting ◽  
Time Dependent ◽  
Death Process ◽  
Similar Time ◽  
Death Rates ◽  
Transition Functions ◽  
Time Dependent Behaviour ◽  
Dependent Behaviour ◽  
Birth Death

We consider birth-death processes taking values in but allow the death rate in state 0 to be positive, so that escape from is possible. Two such processes with transition functions are said to be similar if, for all there are constants c ij such that for all t ≥ 0. We determine conditions on the birth and death rates of a birth-death process for the process to be a member of a family of similar processes, and we identify the members of such a family. These issues are also resolved in the more general setting in which the two processes are called similar if there are constants c ij and ν such that for all t ≥ 0.

scholarly journals Unique mutational changes in SARS-CoV-2 genome: A case study for the largest state of India

2020 ◽  
Author(s):  
Priti Prasad ◽  
Shantanu Prakash ◽  
Kishan Sahu ◽  
Babita Singh ◽  
Suruchi Shukla ◽  
...  
Keyword(s):  
Death Rate ◽  
Uttar Pradesh ◽  
Third Generation ◽  
Phylogenetic Clustering ◽  
Third Generation Sequencing ◽  
Global Pandemic ◽  
Sequencing Technique ◽  
Larger Sample ◽  
Generation Sequencing

AbstractCOVID-19 is a global pandemic causing more than 8 million deaths till mid-August, 2020. In India, more than 3 million confirmed cases have been reported although with relatively low death rate of 1.8%. In this study, we sequenced 47 genomes of SARS-CoV-2 from the patients of 13 districts of Uttar Pradesh (UP), the largest state of India using third-generation sequencing technique. The phylogenetic clustering revealed that no UP sample was aligned with the previously defined USA clade, where the mortality was high. We identified 56 distinct SNP variations in the genomes of UP resulting in a unique mutation rate of 1.19% per sequence, which is greater than the value 0.88% obtained for the rest of India. The relatively less death rate in UP indicates that the mutation in the virus is deleterious. Further investigation is required with larger sample size to determine the degree of virulence vis-a-vis SNP variation.

Can Cannabinoids Suppress the Cytokines Cascade in Patients with Coronavirus Disease COVID-19? A mini-review

Coronaviruses ◽  
2020 ◽  
Vol 01 ◽  
Author(s):  
Hanane Zaki ◽  
Mohammed Bouachrine
Keyword(s):  
Clinical Management ◽  
Death Rate ◽  
Potential Role ◽  
Nasal Congestion ◽  
Immune Systems ◽  
Runny Nose ◽  
Important Target ◽  
Global Pandemic

: Coronavirus disease-2019 (COVID-19), caused by SARS-CoV-2, has started in Wuhan China in December 2019 and becomes a global pandemic. According to WHO, more than fourteen million cases are reported and thousands of casualties worldwide (until July 18, 2020) . Most of the COVID-19 patients have symptoms such as fever, feeling tired, dry cough. Some people may also experience aches and pains, nasal congestion, a runny nose, and diarrhea. So far doctors have been using treatment to relieve symptoms and give patients' immune systems time to regain control of this virus. Many studies have highlighted the important role of cytokine cascades in the death rate in COVID-19 patients. Therefore, inhibition of this phenomenon has become a very important target in the clinical management of this disease. With this idea, in this minireview, we will focus on the potential role of cannabinoids in the suppression of cytokines cascades in patients with COVID-19 and their importance in the clinical management of this disease.

scholarly journals Families of birth-death processes with similar time-dependent behaviour

2000 ◽  
Vol 37 (3) ◽  
pp. 835-849 ◽  
Author(s):  
R. B. Lenin ◽  
P. R. Parthasarathy ◽  
W. R. W. Scheinhardt ◽  
E. A. van Doorn
Keyword(s):  
Death Rate ◽  
General Setting ◽  
Time Dependent ◽  
Death Process ◽  
Similar Time ◽  
Death Rates ◽  
Transition Functions ◽  
Time Dependent Behaviour ◽  
Dependent Behaviour ◽  
Birth Death

We consider birth-death processes taking values in but allow the death rate in state 0 to be positive, so that escape from is possible. Two such processes with transition functions are said to be similar if, for all there are constants cij such that for all t ≥ 0. We determine conditions on the birth and death rates of a birth-death process for the process to be a member of a family of similar processes, and we identify the members of such a family. These issues are also resolved in the more general setting in which the two processes are called similar if there are constants cij and ν such that for all t ≥ 0.

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