scholarly journals Modelling the Hepatitis C with Different Types of Virus Genome

2006 ◽  
Vol 7 (1) ◽  
pp. 3-13 ◽  
Author(s):  
I. A. Moneim ◽  
G. A. Mosa
Keyword(s):  
Hepatitis C ◽  
Rna Virus ◽  
Virus Genome ◽  
Variable Number ◽  
Sequence Heterogeneity ◽  
Transmission Rates ◽  
Reproduction Numbers ◽  
Threshold Conditions ◽  
The World ◽  
Different Types

Hepatitis C virus (HCV) is one of the leading known causes of liver disease in the world. The HCV is a single-stranded RNA virus. The genomes of HCV display significant sequence heterogeneity and have been classified into types and subtypes. Types from 1 to 11 have so far been recognized, each type having a variable number of subtypes. It has been confirmed that 90% approximately of the isolates HCV infections in Egypt belong to a single subtype (4a) [10]. In this paper, we construct a mathematical model to study the spread of HCV-subtype 4a amongst the Egyptian population. The relation between HCV-subtype 4a and the other subtypes has also been studied. The values of reproduction numbersR01,R02have been derived [5]. Also, threshold conditions for the value of the transmission ratesk1andk02, in terms ofR01,R02and the mutation factor μ have been determined to insure that the disease will die out. If the conditions fail to happen the disease takes off and becomes endemic.

scholarly journals A hepatitis C patológiája

2015 ◽  
Vol 156 (21) ◽  
pp. 836-839 ◽  
Author(s):  
Zsuzsa Schaff ◽  
Alíz Gógl ◽  
Réka Dóra ◽  
Tünde Halász
Keyword(s):  
Chronic Hepatitis ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Activity Index ◽  
Rna Virus ◽  
Lymphocytic Infiltration ◽  
Virus Genome ◽  
Histological Characteristics ◽  
Histology Activity Index ◽  
Direct Acting

The hepatitis C virus is an RNA virus, which belongs to the genus Hepaciviruses of the family Flaviviridae. Chronic hepatitis, cirrhosis, and ultimately even liver cancer may develop in over 80% of infected cases. The histological features of hepatitis C and hepatitis caused by other hepatotropic viruses show many similarities, however, certain specific histological characteristics are observable. Accordingly, intense lymphocytic infiltration around the periportal areas, steatosis and biliary alterations are frequent findings. Further characteristics of hepatitis C include liver cell destruction (apoptosis, necrosis), periportal inflammation and fibrosis, the degrees of which can be determined by means of the histology activity index. Our knowledge on the hepatitis C virus genome and the mechanism of replication of the virus have established the use of modern, direct-acting antivirals in the treatment of chronic hepatitis C. Orv. Hetil., 2015, 156(21), 836–839.

Knowledge and Awareness of Dengue Fever

2018 ◽  
pp. 219-222
Author(s):  
Y. Arockia Suganthi ◽  
Chitra K. ◽  
J. Magelin Mary
Keyword(s):  
Dengue Fever ◽  
Prevention And Control ◽  
Control Measures ◽  
Infection Transmission ◽  
Standard Guideline ◽  
The World ◽  
Different Types ◽  
Prevention And Control Measures ◽  
Dengue Prevention ◽  
And Control

Dengue fever is a painful mosquito-borne infection caused by different types of virus in various localities of the world. There is no particular medicine or vaccine to treat person suffering from dengue fever. Dengue viruses are transmitted by the bite of female Aedes (Ae) mosquitoes. Dengue fever viruses are mainly transmitted by Aedes which can be active in tropical or subtropical climates. Aedes Aegypti is the key step to avoid infection transmission to save millions of people in all over the world. This paper provides a standard guideline in the planning of dengue prevention and control measures. At the same time gives the priorities including clinical management and hospitalized dengue patients have to address essentially.

Platón, Einstein y el triunfo de la imaginatividad cosmológica

1998 ◽  
pp. 87-98
Author(s):  
T. M. Robinson
Keyword(s):  
Dynamic Model ◽  
Striking Similarity ◽  
Empirical World ◽  
The World ◽  
Modern Cosmology ◽  
Different Types ◽  
Physical Objects ◽  
Changing World

This article argues the following five claims: 1. Plato’s description of the origins of cosmos in the Timaeus is not a myth, nor something unlikely: when he called it an eikos mythos or eikos logos, he meant a likely or trustworthy account on this very subject. 2. Among the details in this account, the following are prominent and surprising: a) the world was fashioned in time, in that precise point that was the beginning of time; b) several kinds of duration can be distinguished in cosmology (mainly eternity, sempiternity, perpetuity and time); and c) space is an entity characterized by movement and tension. 3. In the Statesman, Plato repeats much the same thing, adding this time the strange notion that the universe’s circular movement is periodically reversed. 4. In spite of the important differences in detail, there is a striking similarity between Plato’s account of the origins of the world and the explanation adopted by much of modern cosmology. 5. What Plato shares with so many instances of recent thought is here termed “cosmological imaginativity”. A first section of the paper deals exclusively with the Timaeus. Claims 1 and 2a are supported by a revision of the meanings of mythos and logos, followed by brief reference and discussion of the argument at Timaeus 27d, leading to the conclusion that Plato affirms that the ever-changing world has indeed had a beginning in time. Claim 2b describes five different types of duration, corresponding to Forms, the Demiurge, Space, the [empirical] world and its contents, physical objects. The second section is concerned with the myth in the Statesman, discussing it as a parallel and describing its peculiar turn to the Timaeus’ cosmology and cosmogony, a complex spheric and dynamic model. After digressing into some important ideas in modern cosmology, touching especially on affinities of some of Einstein’s ideas with of Plato’s own, the paper closes with a discussion of cosmological imaginativity, oriented to recover and recognize fully Plato’s greatness as a cosmologist.

Effective Altruism

2019 ◽  
Keyword(s):  
Animal Welfare ◽  
Poverty Alleviation ◽  
Future Generations ◽  
Global Poverty ◽  
Global Community ◽  
Helping Others ◽  
The World ◽  
Different Types ◽  
Effective Altruism

The effective altruism movement consists of a growing global community of people who organize significant parts of their lives around two key ideas, represented in its name. Altruism: If we use a significant portion of the resources in our possession—whether money, time, or talents—with a view to helping others, we can improve the world considerably. Effectiveness: When we do put such resources to altruistic use, it is crucial to focus on how much good this or that intervention is reasonably expected to do per unit of resource expended (for example, per dollar donated). While global poverty is a widely used case study in introducing and motivating effective altruism, if the ultimate aim is to do the most good one can with the resources expended, it is far from obvious that global poverty alleviation is highest priority cause area. In addition to ranking possible poverty-alleviation interventions against one another, we can also try to rank interventions aimed at very different types of outcome against one another. This includes, for example, interventions focusing on animal welfare or future generations. The scale and organization of the effective altruism movement encourage careful dialogue on questions that have perhaps long been there, throwing them into new and sharper relief, and giving rise to previously unnoticed questions. In the present volume, the first of its kind, a group of internationally recognized philosophers, economists, and political theorists contribute in-depth explorations of issues that arise once one takes seriously the twin ideas of altruistic commitment and effectiveness.

scholarly journals Ever-increasing viral diversity associated with the red imported fire ant Solenopsis invicta (Formicidae: Hymenoptera)

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
César Augusto Diniz Xavier ◽  
Margaret Louise Allen ◽  
Anna Elizabeth Whitfield
Keyword(s):  
Solenopsis Invicta ◽  
De Novo ◽  
Rna Virus ◽  
Housekeeping Genes ◽  
Virus Genome ◽  
Single Strand ◽  
Viral Diversity ◽  
Red Imported Fire Ant ◽  
Sequence Comparisons ◽  
Data Set

Abstract Background Advances in sequencing and analysis tools have facilitated discovery of many new viruses from invertebrates, including ants. Solenopsis invicta is an invasive ant that has quickly spread worldwide causing significant ecological and economic impacts. Its virome has begun to be characterized pertaining to potential use of viruses as natural enemies. Although the S. invicta virome is the best characterized among ants, most studies have been performed in its native range, with less information from invaded areas. Methods Using a metatranscriptome approach, we further identified and molecularly characterized virus sequences associated with S. invicta, in two introduced areas, U.S and Taiwan. The data set used here was obtained from different stages (larvae, pupa, and adults) of S. invicta life cycle. Publicly available RNA sequences from GenBank’s Sequence Read Archive were downloaded and de novo assembled using CLC Genomics Workbench 20.0.1. Contigs were compared against the non-redundant protein sequences and those showing similarity to viral sequences were further analyzed. Results We characterized five putative new viruses associated with S. invicta transcriptomes. Sequence comparisons revealed extensive divergence across ORFs and genomic regions with most of them sharing less than 40% amino acid identity with those closest homologous sequences previously characterized. The first negative-sense single-stranded RNA virus genomic sequences included in the orders Bunyavirales and Mononegavirales are reported. In addition, two positive single-strand virus genome sequences and one single strand DNA virus genome sequence were also identified. While the presence of a putative tenuivirus associated with S. invicta was previously suggested to be a contamination, here we characterized and present strong evidence that Solenopsis invicta virus 14 (SINV-14) is a tenui-like virus that has a long-term association with the ant. Furthermore, based on virus sequence abundance compared to housekeeping genes, phylogenetic relationships, and completeness of viral coding sequences, our results suggest that four of five virus sequences reported, those being SINV-14, SINV-15, SINV-16 and SINV-17, may be associated to viruses actively replicating in the ant S. invicta. Conclusions The present study expands our knowledge about viral diversity associated with S. invicta in introduced areas with potential to be used as biological control agents, which will require further biological characterization.

Comprehensive Effects of Short-Term Rental Platforms Across Hotel Types in U.S. and International Destinations

2021 ◽  
pp. 193896552110335
Author(s):  
John W. O’Neill ◽  
Jihwan Yeon
Keyword(s):  
Service Providers ◽  
Comprehensive Analysis ◽  
Competitive Market ◽  
Substitution Effects ◽  
Short Term ◽  
Hotel Performance ◽  
The World ◽  
Different Types ◽  
Location Type ◽  
The Impact

In recent years, short-term rental platforms in the lodging sector, including Airbnb, VRBO, and HomeAway, have received extensive attention and emerged as potentially alternative suppliers of services traditionally provided by established commercial accommodation providers, that is, hotels. Short-term rentals have dramatically increased the available supply of rooms for visitors to multiple international destinations, potentially siphoning demand away from hotels to short-term rental businesses. In a competitive market, an increase in supply with constant demand would negatively influence incumbent service providers. In this article, we examine the substitution effects of short-term rental supply on hotel performance in different cities around the world. Specifically, we comprehensively investigate the substitution effects of short-term rental supply on hotel performance based on hotel class, location type, and region. Furthermore, we segment the short-term rental supply based on its types of accommodations, that is, shared rooms, private rooms, and entire homes, and both examine and quantify the differential effects of these types of short-term rentals on different types of hotels. This study offers a comprehensive analysis regarding the impact of multiple short-term rental platforms on hotel performance and offers both conceptual and practical insights regarding the nature and extent of the effects that were identified.

Present and Future Prospects for Using Alternatives to Chimpanzees in Research

1995 ◽  
Vol 23 (5) ◽  
pp. 634-641
Author(s):  
Gill Langley
Keyword(s):  
Hepatitis C ◽  
Human Studies ◽  
Future Prospects ◽  
Hepatitis C Infection ◽  
Ethical Concerns ◽  
Human Volunteers ◽  
Different Types

Three chimpanzee studies of hepatitis C infection were found to be duplicative of each other and of research with human volunteers. Research into taste neurophysiology also used chimpanzees, although data which are highly relevant (but less specific) can be obtained from human studies. The use of chimps to study benzene metabolism was found to be poorly planned and unjustifiable. Scientifically, chimps are not always the best “models” for humans, and their use raises insurmountable ethical concerns. Many alternatives are already available, but researchers will need to adjust their perspectives on the usefulness of different types of data.

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