scholarly journals Taxonomic patterns in the zoonotic potential of mammalian viruses

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5979 ◽  
Author(s):  
Alex D. Washburne ◽  
Daniel E. Crowley ◽  
Daniel J. Becker ◽  
Kevin J. Olival ◽  
Matthew Taylor ◽  
...  
Keyword(s):  
Infectious Disease ◽  
At Risk ◽  
Life Histories ◽  
Coarse Graining ◽  
International Committee ◽  
Zoonotic Potential ◽  
Human Host ◽  
Disease Biology ◽  
Taxonomic Patterns

Predicting and simplifying which pathogens may spill over from animals to humans is a major priority in infectious disease biology. Many efforts to determine which viruses are at risk of spillover use a subset of viral traits to find trait-based associations with spillover. We adapt a new method—phylofactorization—to identify not traits but lineages of viruses at risk of spilling over. Phylofactorization is used to partition the International Committee on Taxonomy of Viruses viral taxonomy based on non-human host range of viruses and whether there exists evidence the viruses have infected humans. We identify clades on a range of taxonomic levels with high or low propensities to spillover, thereby simplifying the classification of zoonotic potential of mammalian viruses. Phylofactorization by whether a virus is zoonotic yields many disjoint clades of viruses containing few to no representatives that have spilled over to humans. Phylofactorization by non-human host breadth yields several clades with significantly higher host breadth. We connect the phylogenetic factors above with life-histories of clades, revisit trait-based analyses, and illustrate how cladistic coarse-graining of zoonotic potential can refine trait-based analyses by illuminating clade-specific determinants of spillover risk.

Discriminating arboviral species

2021 ◽  
Vol 102 (4) ◽  
Author(s):  
Yiyuan Li ◽  
Angela C. O’Donnell ◽  
Howard Ochman
Keyword(s):  
Evolutionary History ◽  
Viral Vectors ◽  
Species Concept ◽  
International Committee ◽  
Biological Species ◽  
Biological Species Concept ◽  
Substantial Variation ◽  
Artificial Boundaries ◽  
Human Infections

Mosquito-borne arboviruses, including a diverse array of alphaviruses and flaviviruses, lead to hundreds of millions of human infections each year. Current methods for species-level classification of arboviruses adhere to guidelines prescribed by the International Committee on Taxonomy of Viruses (ICTV), and generally apply a polyphasic approach that might include information about viral vectors, hosts, geographical distribution, antigenicity, levels of DNA similarity, disease association and/or ecological characteristics. However, there is substantial variation in the criteria used to define viral species, which can lead to the establishment of artificial boundaries between species and inconsistencies when inferring their relatedness, variation and evolutionary history. In this study, we apply a single, uniform principle – that underlying the Biological Species Concept (BSC) – to define biological species of arboviruses based on recombination between genomes. Given that few recombination events have been documented in arboviruses, we investigate the incidence of recombination within and among major arboviral groups using an approach based on the ratio of homoplastic sites (recombinant alleles) to non-homoplastic sites (vertically transmitted alleles). This approach supports many ICTV-designations but also recognizes several cases in which a named species comprises multiple biological species. These findings demonstrate that this metric may be applied to all lifeforms, including viruses, and lead to more consistent and accurate delineation of viral species.

Evolution and environment in the late Silurian-early Devonian: the rise of the pteridophytes

1985 ◽  
Vol 309 (1138) ◽  
pp. 147-165 ◽  
Keyword(s):  
Vascular Plants ◽  
Preliminary Report ◽  
Life Histories ◽  
Early History ◽  
Flora Of Australia ◽  
Early Devonian ◽  
The World ◽  
History Of

A brief review of the major advances since 1979 in Silurian and Devonian palaeobotany is followed by a preliminary report on a Gedinnian assemblage from the Welsh Borderland. This is dominated by rhyniopsids and includes several species of Cooksonia and Salopella . Spores have been isolated from a number of taxa. The assemblage is used to illustrate the problems of recognition and classification of early vascular plants. Parallel sedimentological and palaeogeographical studies permit speculation on the ecology and life histories of the plants that colonized the Old Red Continent. It is concluded that the lack of well preserved and independently dated assemblages from elsewhere in the world (an exception being the Baragwanathia flora of Australia) prevents the detection of any provincialism in the late Silurian and early Devonian and makes generalizations on the early history of vascular plants premature.

scholarly journals Fungal diseases of tree stands under urbanized conditions of Moscow

2013 ◽  
pp. 241-247
Author(s):  
Oksana Smirnova ◽  
Aleksej Smirnov
Keyword(s):  
At Risk ◽  
Support System ◽  
Dynamic Equilibrium ◽  
Fungal Diseases ◽  
Ecological Situation ◽  
Fomitopsis Pinicola ◽  
Phellinus Igniarius ◽  
Fomes Fomentarius ◽  
Experimental Station

Phytosanitary and ecological estimation of tree-stands has been con?ducted at the Forest Experimental Station of Moscow Agricultural Academy and parks of Northeast of Moscow in 2007-2011. Fomes fomentarius was proved to be a very serious pathogen of trees under conditions of Moscow, Piptoporus betulinus, Phellinus igniarius, and Fomitopsis pinicola also occurred and caused damage to trees. This rather bad phytosanitary situation depends on alarming ecological situation in Moscow. At the Forest Experimental Station of Moscow Agricultural Academy a number and cover of lichens decreased. In general, all trees in Moscow are in dynamic equilibrium with the urbanized environment. In connection with this, the following classification of tree-stands was proposed for the urbanized environment: 1 - healthy trees, 2 - affected trees which can be managed, 3 - dry woods, 3a - very diseased. Many tree-stands in investigated regions of Moscow are found to belong to the groups 2 and 3c. All tree-stands must be carefully monitored and managed in order to provide a well-timed decision on the support system for preservation of trees as ?lungs of city? and avoid unpredictable tree falling which put people and traffic at risk.

Self-Concept Correlates between At-Risk and Not-At-Risk Ninth-Grade Students

1995 ◽  
Vol 76 (2) ◽  
pp. 683-687 ◽  
Author(s):  
Mary H. Jackson ◽  
Kimberly B. Reddick ◽  
Richard G. Dubes
Keyword(s):  
At Risk ◽  
Ninth Grade ◽  
Self Concept ◽  
Dropping Out ◽  
Satisfaction Scale ◽  
Ninth Grade Students ◽  
Not At Risk ◽  
Multivariate Discriminant ◽  
Item Scale

This study examined whether the Tennessee Self-concept Scales could be used to discriminate among 43 ninth-grade students who were designated as being at risk of dropping out of high school and 47 students who were thought to show probability of persisting. Scores on the scales were submitted to stepwise multivariate discriminant analysis. Scores on the Self-satisfaction Scale constituted a linear function that correctly classified 72.22% of the subjects. Further investigation confirmed a 13-item scale selected from the Tennessee Self-concept Scales correctly identified the classification of 76.67% of the students.

scholarly journals Linking sex differences to the evolution of infectious disease life-histories

2018 ◽  
Vol 373 (1757) ◽  
pp. 20170431 ◽  
Author(s):  
Matthew D. Hall ◽  
Nicole Mideo
Keyword(s):  
Infectious Disease ◽  
Sex Differences ◽  
Life Histories ◽  
Test Case ◽  
Theme Issue ◽  
Genetic Covariance ◽  
Covariance Functions ◽  
Genetic Constraint ◽  
Males And Females ◽  
Evolutionary Consequences

Sex differences in the prevalence, course and severity of infection are widespread, yet the evolutionary consequences of these differences remain unclear. Understanding how male–female differences affect the trajectory of infectious disease requires connecting the contrasting dynamics that pathogens might experience within each sex to the number of susceptible and infected individuals that are circulating in a population. In this study, we build on theory using genetic covariance functions to link the growth of a pathogen within a host to the evolution and spread of disease between individuals. Using the Daphnia–Pasteuria system as a test case, we show that on the basis of within-host dynamics alone, females seem to be more evolutionarily liable for the pathogen, with higher spore loads and greater divergence among pathogen genotypes as infection progresses. Between-host transmission, however, appears to offset the lower performance of a pathogen within a male host, making even subtle differences between the sexes evolutionarily relevant, as long as the selection generated by the between-host dynamics is sufficiently strong. Our model suggests that relatively simple differences in within-host processes occurring in males and females can lead to complex patterns of genetic constraint on pathogen evolution, particularly during an expanding epidemic. This article is part of the theme issue ‘Linking local adaptation with the evolution of sex differences’.

Tracking self-reported symptoms and medical conditions on social media during the COVID-19 pandemic (Preprint)

2021 ◽  
Author(s):  
Qinglan Ding ◽  
Daisy Massey ◽  
Chenxi Huang ◽  
Connor Grady ◽  
Yuan Lu ◽  
...  
Keyword(s):  
Mental Health ◽  
Infectious Disease ◽  
Social Media ◽  
Positive Predictive Value ◽  
Medical Condition ◽  
Medical Conditions ◽  
Health Related ◽  
The U.S ◽  
Over Time

BACKGROUND Harnessing health-related data posted on social media in real-time has the potential to offer insights into how the pandemic impacts the mental health and general well-being of individuals and populations over time. OBJECTIVE The aim of this study was to obtain information on symptoms and medical conditions self-reported by non-Twitter social media users during the coronavirus disease 2019 (COVID-19) pandemic, and to determine how discussion of these symptoms and medical conditions on social media changed over time. METHODS We used natural language processing (NLP) algorithms to identify symptom and medical condition topics being discussed on social media between June 14 and December 13, 2020. The sample social media posts were geotagged by NetBase, a third-party data provider. We calculated the positive predictive value and sensitivity to validate the classification of the posts. We also assessed the frequency of different health-related discussions on social media over time during the study period, and compared the changes in the frequency of each symptom/medical condition discussion to the fluctuation of U.S. daily new COVID-19 cases during the study period. Additionally, we compared the trends of the 5 most commonly mentioned symptoms and medical conditions from June 14 to August 31 (when the U.S. passed 6 million COVID-19 cases) to the trends observed from September 1 to December 13, 2020. RESULTS Within a total of 9,807,813 posts (nearly 70% were sourced from the U.S.), we identified discussion of 120 symptom topics and 1,542 medical condition topics. Our classification of the health-related posts had a positive predictive value of over 80% and an average classification rate of 92% sensitivity. The 5 most commonly mentioned symptoms on social media during the study period were: anxiety (in 201,303 posts or 12.2% of the total posts mentioning symptoms), generalized pain (189,673, 11.5%), weight loss (95,793, 5.8%), fatigue (91,252, 5.5%), and coughing (86,235, 5.2%). The 5 most discussed medical conditions were: COVID-19 (in 5,420,276 posts or 66.4% of the total posts mentioning medical conditions), unspecified infectious disease (469,356, 5.8%), influenza (270,166, 3.3%), unspecified disorders of the central nervous system (253,407, 3.1%), and depression (151,752, 1.9%). The changes in the frequency of 2 medical conditions, COVID-19 and unspecified infectious disease, were similar to the fluctuation of daily new confirmed cases of COVID-19 in the U.S. CONCLUSIONS COVID-19 and symptoms of anxiety were the two most commonly discussed health-related topics on social media from June 14 to December 13, 2020. Real-time monitoring of social media posts on symptoms and medical conditions may help assess the population's mental health status and enhance public health surveillance for infectious disease.

Corneal Dystrophy in Dutch Belted Rabbits as a Possible Model of Thiel-Behnke Subtype of Epithelial-Stromal TGFβ-Induced Corneal Dystrophy

2020 ◽  
pp. 019262332096809
Author(s):  
JoAnn C. L. Schuh ◽  
Dana L. Holve ◽  
Karen E. Mundwiler
Keyword(s):  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Corneal Opacity ◽  
Corneal Dystrophy ◽  
International Committee ◽  
Corneal Dystrophies ◽  
Transmission Electron ◽  
Oct Imaging ◽  
Small Clusters

The International Committee for Classification of Corneal Dystrophies (IC3D) categorized corneal dystrophies in humans using anatomic, genotypic, and clinicopathologic phenotypic features. Relative to the IC3D classification, a review of the veterinary literature confirmed that corneal dystrophy is imprecisely applied to any corneal opacity and to multiple poorly characterized histologic abnormalities of the cornea in animals. True corneal dystrophy occurs in mice with targeted mutations and spontaneously in pet dogs and cats and in Dutch belted (DB) rabbits, but these instances lack complete phenotyping or genotyping. Corneal dystrophy in DB rabbits can be an important confounding finding in ocular toxicology studies but has only been described once. Therefore, the ophthalmology and pathology of corneal dystrophy in 13 DB rabbits were characterized to determine whether the findings were consistent with or a possible model of any corneal dystrophy subtypes in humans. Slit lamp and optical coherence tomography (OCT) imaging were used to characterize corneal dystrophy over 4 months in young DB rabbits. The hyperechoic OCT changes correlated with light microscopic findings in the anterior stroma, consisting of highly disordered collagen fibers and enlarged keratocytes. Histochemical stains did not reveal abnormal deposits. Small clusters of 8 to 16 nm diameter curly fibers identified by transmission electron microscopy were consistent with Thiel-Behnke (TBCD) subtype of epithelial-stromal transforming growth factor β-induced dystrophies. Sporadic corneal dystrophy in DB rabbits appears to be a potential animal model of TBCD, but genotypic characterization will be required to confirm this categorization.

Chronic Depression

1988 ◽  
Vol 153 (3) ◽  
pp. 287-297 ◽  
Author(s):  
Jan Scott
Keyword(s):  
At Risk ◽  
Major Depression ◽  
Personality Traits ◽  
Chronic Depression ◽  
Dysthymic Disorder ◽  
Minor Depression ◽  
Illness Episode ◽  
Persistent Symptoms ◽  
Double Depression

Defining chronic depression as persistent symptoms for 2 or more years, a prevalence of chronic depression of 12–15% is found in the literature. A four-part classification of chronic depression is proposed: Chronic Primary Major Depression; Chronic Secondary Major Depression; Characterological or Chronic Minor Depression (Dysthymic Disorder); and ‘Double Depression’. The literature indicates several factors predicting chronicity in primary major depression: more at risk are female patients, particularly those with premorbid neurotic personality traits, individuals with unipolar disorders, and those with higher familial loading for such disorders. Other factors are the adequacy and appropriateness of the treatment given, and the length of illness episode prior to treatment being received. Larger studies with well-matched controls are needed.

Summary of recommendations of nomenclature committees relevant to clay mineralogy: report of the Association Internationale pour l'Etude des Argiles (AIPEA) Nomenclature Committee for 2006

Clay Minerals ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 863-877 ◽  
Author(s):  
S. Guggenheim ◽  
J. M. Adams ◽  
D. C. Bain ◽  
F. Bergaya ◽  
M. F. Brigatti ◽  
...  
Keyword(s):  
Clay Minerals ◽  
International Collaboration ◽  
International Association ◽  
Clay Mineralogy ◽  
International Committee ◽  
Nomenclature Committee ◽  
Group Meetings

Brindley et al. (1951) reported the earliest efforts to obtain international collaboration on nomenclature and classification of clay minerals, initiated at the International Soil Congress in Amsterdam in 1950. Since then, national clay groups were formed, and they proposed various changes in nomenclature at group meetings of the International Clay Conferences. Most of the national clay groups have representation on the Nomenclature Committee of the Association Internationale pour l'Etude des Argiles (AIPEA, International Association for the Study of Clays), which was established in 1966. The precursor committee to the AIPEA Nomenclature Committee was the Nomenclature Subcommittee of the Comité International pour l'Etude des Argiles (OPEA, International Committee for the Study of Clays).

scholarly journals Intelligent Analysis of Premature Ventricular Contraction Based on Features and Random Forest

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Tiantian Xie ◽  
Runchuan Li ◽  
Shengya Shen ◽  
Xingjin Zhang ◽  
Bing Zhou ◽  
...  
Keyword(s):  
At Risk ◽  
Random Forest ◽  
Premature Ventricular Contraction ◽  
Ventricular Contraction ◽  
Rr Intervals ◽  
Intelligent Analysis

Premature ventricular contraction (PVC) is one of the most common arrhythmias in the clinic. Due to its variability and susceptibility, patients may be at risk at any time. The rapid and accurate classification of PVC is of great significance for the treatment of diseases. Aiming at this problem, this paper proposes a method based on the combination of features and random forest to identify PVC. The RR intervals (pre_RR and post_RR), R amplitude, and QRS area are chosen as the features because they are able to identify PVC better. The experiment was validated on the MIT-BIH arrhythmia database and achieved good results. Compared with other methods, the accuracy of this method has been significantly improved.

Sign in / Sign up

Export Citation Format

Share Document