THE SIX-SPOTTED LEAFHOPPER, MACROSTELES FASCIFRONS (STÅL.) AND ASTER YELLOWS IN MANITOBA

1961 ◽  
Vol 41 (2) ◽  
pp. 320-331 ◽  
Author(s):  
P. H. Westdal ◽  
C. F. Barrett ◽  
H. P. Richardson
Keyword(s):  
Local Population ◽  
Virus Transmission ◽  
Migrant Population ◽  
Yellow Virus ◽  
Aster Yellow ◽  
Aster Yellows ◽  
Percentage Transmission ◽  
Early Maturing ◽  
General Field ◽  
New Generation

The six-spotted leafhopper overwintered in the egg stage only. Adults migrated into Manitoba in substantial numbers on strong south winds in mid-May. The migrant population reached a peak of about 80 leafhoppers per 100 sweeps in mid-June on cereals. There was a high mortality of migrants in late June and early July. The non-migrant population originated partly from overwintered eggs but mostly from eggs laid by migrants. New generation adults appeared in late June. Distinct broods were not apparent in the field because generations overlapped. The peak of population, about 400 leafhoppers per 100 sweeps, was reached about mid-August. Four generations were reared in a year. In general field collections the percentage of leafhoppers transmitting the aster yellow virus did not exceed 1 per cent. The percentage transmission was highest in the migrant population but dropped in July and August with the increase in local population. The rate of virus transmission was low in June and July but reached a peak in August in conjunction with the peak in population. Some weeds are a source of aster yellows virus. In Manitoba, early maturing crops generally escape severe aster yellows infection but it is often a problem on late crops.

scholarly journals Simulating Acculturation Dynamics Between Migrants and Locals in Relation to Network Formation

2019 ◽  
Vol 38 (4) ◽  
pp. 365-386
Author(s):  
Rocco Paolillo ◽  
Wander Jager
Keyword(s):  
Network Formation ◽  
Local Population ◽  
Cultural Integration ◽  
Refugee Crisis ◽  
Migrant Population ◽  
Cultural Groups ◽  
Acculturation Strategies ◽  
Agent Based ◽  
Polarization Effects ◽  
Mutual Adaptation

International migration implies the coexistence of different ethnic and cultural groups in the receiving country. The refugee crisis of 2015 has resulted in critical levels of opinion polarization on the question of whether to welcome migrants causing clashes in receiving countries. This scenario emphasizes the need to better understand the dynamics of mutual adaptation between locals and migrants and the conditions that favor successful integration. Agent-based simulations can help achieve this goal. In this work, we introduce our model MigrAgent and our preliminary results. The model synthesizes the dynamics of migration intake and postmigration adaptation. It explores the different acculturation outcomes that can emerge from the mutual adaptation of a migrant population and a local population depending on their degree of tolerance. With parameter sweeping, we detect how different acculturation strategies can coexist in a society and in different degrees among various subgroups. The results show higher polarization effects between a local population and a migrant population for fast intake conditions. When migrant intake is slow, transitory conditions between acculturation outcomes emerge for subgroups, for example, from assimilation to integration for liberal migrants and from marginalization to separation for conservative migrants. Relative group sizes due to speed of intake cause counterintuitive scenarios such as the separation of liberal locals. We qualitatively compare the processes of our model with the German portion sample of the survey “Causes and Consequences of Socio-Cultural Integration Processes Among New Immigrants in Europe,” finding preliminary confirmation of our assumptions and results.

scholarly journals Epidemiological study on hand, foot and mouth disease in Tongzhou District, Beijing, 2013–2017

2019 ◽  
Vol 47 (6) ◽  
pp. 2615-2625 ◽  
Author(s):  
Xiao-Feng Liu ◽  
Xiu-Mei Sun ◽  
Xiao-Wei Sun ◽  
Yu-Qing Yang ◽  
Cong-Hui Huang ◽  
...  
Keyword(s):  
Incidence Rate ◽  
Local Population ◽  
Foot And Mouth Disease ◽  
Mouth Disease ◽  
Migrant Population ◽  
Enterovirus A71 ◽  
Tongzhou District ◽  
Foot And Mouth ◽  
Polymerase Chain ◽  
Epidemiological Characteristics

Objective To study the epidemiological characteristics of hand, foot and mouth disease (HFMD) in Tongzhou District, Beijing between 2013 and 2017. Methods Data on HFMD infections from 1 January 2013 to 31 December 2017 were collected from the Notifiable Infectious Diseases Reporting Information System and analysed. Serotyping of enteroviruses from samples from patients with HFMD was undertaken using reverse transcription–polymerase chain reaction. Results A total of 15 341 patients with HFMD were reported and 32 patients (0.2%) were classified as having severe HFMD. The annual mean incidence rate of HFMD was 219.3/100 000 of the general population. The incidence and case-severity rates of HFMD generally decreased between 2013 and 2017. In the floating migrant population, the incidence and cases-severity rates of HFMD were significantly higher than in the local population. The peak incidence and severity-case rates were at 2 years of age and > 90% of patients were ≤5 years. Enterovirus A71 and Coxsackievirus A16 were the predominant pathogens in 2013–2017. Conclusions During the 5-year period 2013–2017, the incidence rate and case-severity rate of HFMD generally decreased in Tongzhou District, Beijing. The floating migrant population and children ≤5 years of age were at the highest risk of HFMD.

Changing Trend of Population Migration in China and Its Spatial Pattern

2016 ◽  
Vol 04 (04) ◽  
pp. 1650032
Author(s):  
Ning WANG
Keyword(s):  
Spatial Pattern ◽  
Migrant Workers ◽  
Active Role ◽  
Small Towns ◽  
Migrant Population ◽  
Balanced Development ◽  
Changing Trend ◽  
New Generation ◽  
The Impact

Based on the data from the sixth national census of the population at the county level, this paper comprehensively analyzes the changing trend of the migration of the population in China and its spatial pattern at national, large regional and urban levels. The results show that: (1) the overall scale of the migration of the population in China presents a constantly increasing trend, and the pattern that the Eastern regions are still the primary destination does not change; however, migration to the Central and Western regions shows a rapid growth; (2) the generational change of the migrant population has obvious characteristics, and a great number of the new generation of migrant workers call for higher demands regarding the quality of future urbanization; (3) the aggregates of the migrant population in cities at the prefecture level and above, especially in metropolises and megacities, are obvious, and small towns play an active role in absorbing the migrant population nearby; (4) the activity of the migration of the population in cities is closely related to their economic development, administrative level, etc. In the future, we should attach importance to the new requirements of urban development proposed by the structural change in the migration of the population, weaken the impact of the urban administrative level on migration, and promote a balanced development of the urban scale system.

scholarly journals Identificação molecular de SARS-CoV-2 em superfícies ambientais em estabelecimentos de saúde de uma universidade pública no Brasil

2021 ◽  
Vol 2 (4) ◽  
pp. 431-441
Author(s):  
Caio Ricardo Eich ◽  
Barbara Scariot Colombelli ◽  
Kattlyn Larissa Candido ◽  
Luciana Oliveira De Fariña
Keyword(s):  
Internal Control ◽  
Local Population ◽  
Genetic Material ◽  
Virus Transmission ◽  
Health Surveillance ◽  
World Health ◽  
Rt Pcr ◽  
Surveillance Studies ◽  
Risk Zones ◽  
Health Organization

Em 11 de março de 2020, a Organização Mundial de Saúde (OMS) decretou a pandemia do COVID-19, causado pelo vírus SARS-CoV-2, responsável por mais de 4,5 milhões de mortes até o momento. Esta nova realidade exigiu respostas por parte das autoridades e da população, a fim de mitigar a propagação do vírus e evitar o colapso do sistema de saúde, assim como estudos de vigilância em saúde, que possibilitaram um melhor entendimento dos mecanismos de transmissão do vírus e possibilitaram identificar zonas de risco dentro de cidades ou ambientes públicos. Este estudo tem o objetivo de identificar a presença do SARS-CoV-2 dentro da Universidade Estadual do Oeste do Paraná, a qual fornece serviços de saúde para a população local, assim como realizar um controle interno no Laboratório de Bioquímica Molecular (LaBioqMol) da universidade, onde são realizados testes de RT-PCR semanalmente. Foram coletadas 21 amostras de áreas frequentemente tocadas por pessoas, cuja presença do RNA viral e de material genético humano foi identificada por RT-PCR. Em nenhuma das amostras foi detectado a presença do vírus. Entretanto, em 8 (38,1%) das amostras foi verificada a amplificação do gene RNaseP, indicando a presença de células humana. Este estudo auxilia no controle e garantia de qualidade do LaBioqMol e fortalece a visão de que a contaminação do ambiente pelo SARS-CoV-2 é provavelmente menos frequente do que foi anteriormente sugerido no início da pandemia.   On March 11, 2020, the World Health Organization (WHO) decreed the pandemic of COVID-19, caused by the SARS-CoV-2 virus, responsible for more than 4.5 million deaths to date. This new reality demanded responses from the authorities and the population in order to mitigate the spread of the virus and avoid the collapse of the health system, as well as health surveillance studies, which enabled a better understanding of the mechanisms of virus transmission and made it possible to identify risk zones within cities or public environments. This study aims to identify the presence of SARS-CoV-2 within the Universidade Estadual do Oeste do Paraná, which provides health services to the local population, as well as to perform an internal control at the university's Molecular Biochemistry Laboratory (LaBioqMol), where RT-PCR tests are performed weekly. Twenty-one samples were collected from areas frequently touched by people, and the presence of viral RNA and human genetic material was identified by RT-PCR. In none of the samples was the presence of the virus detected. However, in 8 (38.1%) of the samples the RNaseP gene amplification was verified, indicating the presence of human cells. This study assists in quality control and assurance at LaBioqMol and strengthens the view that environmental contamination by SARS-CoV-2 is probably less frequent than was previously suggested at the beginning of the pandemic.

scholarly journals ESTIMATE OF VIRUS ZIKA SPREAD RISK IN THE REPUBLIC OF ABKHAZIA ASSOCIATING THE LOCAL POPULATION OF MOSQUITOES AEDES AEGYPTI AND AEDES ALBOPICTUS

2017 ◽  
pp. 10-15
Author(s):  
O. V. Maletskaya ◽  
V. M. Dubyansky ◽  
A. I. Belyaeva ◽  
L. I. Shaposhnikova ◽  
D. S. Agapitov ◽  
...  
Keyword(s):  
Zika Virus ◽  
Vector Competence ◽  
Local Population ◽  
Virus Transmission ◽  
The Black Sea ◽  
Control Methods ◽  
Black Sea Coast ◽  
The Russian Federation ◽  
The Republic ◽  
Virus Zika

Aim. Chracteristic of number and distribution of mosquitoes Ae. aegypti and Ae. albopictus in the Republic of Abkhazia and a risk assessment of virus Zika spread. Materials and methods. The accounting of mosquitoes number was made by the method «on the observer» in 20 minutes at the 70 nature landscapes points in april-oktober 2016. Results. The Black sea coast of the Republic of Abkhazia has favorable ecological conditions for the mosquitoes ingrowth of Ae. aegypti and Ae. albopictus. At 2016 the mosquitoes Ae. albopictus having vector competence to spread a Zika virus, has been revealed in the open stations in the territory from Ochamchirsky district to border with the Russian Federation. Their number is correlated with the air temperature in the region. The control of efficiency of the insecticidal works showed that in the open stations Ae. albopictus were not found within 3 - 7 days after the disinsection actions. However, their number of recovered as a result of settling from nearby natural biotopes. Conclusion. The risk of local Zika virus transmission has estimated as a low. Considering the gravity of the disease caused by the Zika virus carrying out a wider complex of the control methods of the mosquitoes number in areas of their dwelling, especially on the epidemiologically significant objects is necessary. The most effective of the population protection action is riddance of the reproduction mosquitoes places and sanitation of territory.

HOST REACTIONS TO THREE STRAINS OF ASTER YELLOWS VIRUS FROM MANITOBA

1967 ◽  
Vol 45 (5) ◽  
pp. 657-664 ◽  
Author(s):  
H. P. Richardson
Keyword(s):  
Plant Species ◽  
Virus Strain ◽  
Lactuca Sativa ◽  
Plant Host ◽  
Aster Yellows ◽  
Thlaspi Arvense ◽  
Virus Source ◽  
Percentage Transmission ◽  
China Aster

One non-celery-infecting strain of aster yellows virus (NAYV) and two celery-infecting strains (CAYV-Z and CAYV) were isolated in Manitoba. Percentage transmission of the three strains of AYV to 13 plant species by single, infective male or female six-spotted leafhoppers (Macrosteles fascifrons (Stål)) given a 2-day inoculation feed varied with the host and virus strain. Head lettuce (Lactuca sativa var. capitata L.), and stinkweed (Thlaspi arvense L.) were superior to China aster (Callistephus chinensis Nees) as indicators of the proportion of infective leafhoppers. Acquisition of virus by vectors fed on the 13 plant species, as indicated by transmission to aster, differed according to strain and host. The differences between hosts in the percentages of plants infected with AYV was attributed to plant host – virus rather than the vector–virus relationships.There was no correlation between the susceptibility of a host and its value as a virus source. Head lettuce was the only one of the 13 plant species tested that was highly susceptible and from which all three strains of AYV could be readily acquired.

scholarly journals Blood-borne virus transmission in an urban, culturally diverse neighbourhood: results from a cross-sectional bio-behavioural survey using innovative outreach methods in a hard-to-reach population

Sexual Health ◽  
2018 ◽  
Vol 15 (1) ◽  
pp. 54 ◽  
Author(s):  
Elizabeth Peach ◽  
Shelley Cogger ◽  
Kat Byron ◽  
Penny Francis ◽  
Daniel O'Keefe ◽  
...  
Keyword(s):  
Culturally Diverse ◽  
Mental Health Problems ◽  
Aboriginal People ◽  
Health Workers ◽  
Screening Program ◽  
Local Population ◽  
Virus Transmission ◽  
Linkage To Care ◽  
Related Factors ◽  
Cross Sectional

Background Following a HIV outbreak among Aboriginal people in a culturally diverse inner-city suburb of Melbourne, a blood-borne virus (BBV) screening program was conducted to inform public health interventions to prevent transmission and facilitate timely diagnosis and linkage to care. Methods: In August–September 2014, community health workers recruited people who inject drugs (PWID) from a local needle and syringe program. Participants were tested for hepatitis C virus (HCV), hepatitis B virus (HBV), HIV and syphilis and completed a bio-behavioural questionnaire. Results: In total, 128 PWID participated in the study. Serological evidence of exposure to HCV and HBV was detected among 118 (93%) and 57 participants (45%) respectively. Five participants were HIV positive. Independent risk factors for needle sharing were Aboriginality (AOR = 6.21, P < 0.001), attending health care for mental health problems (AOR = 2.79, P = 0.023) and inability to access drug treatment in the previous 6 months (AOR = 4.34, P = 0.023). Conclusions: BBV prevalence in this sample was much higher than reported in other recent Australian studies. This local population is at high risk of further BBV transmission, particularly Aboriginal PWID. Individual and service-related factors associated with risk in the context of a dynamic urban drug culture and HIV outbreak suggest an urgent need for tailored harm-reduction measures.

scholarly journals SECONDARY EDUCATION OF THE 1920’s IN THE SOVIET PROVINCE

2020 ◽  
pp. 5-9
Author(s):  
M. Asanishvili
Keyword(s):  
Secondary Education ◽  
Soviet Union ◽  
Local Population ◽  
School Life ◽  
The Soviet Union ◽  
New Ideas ◽  
The One ◽  
In The Beginning ◽  
New Generation ◽  
Labor School

During the existence of the USSR, the Bolsheviks wanted to built a new class system in which workers would be the main social group. School in this context should have been included children to the adulthood from a young age. A tool of reeducation and breakdown of a child's life was a work. The reform of secondary education in the 1920s in the USSR meant the beginning of the cultural, social and economic dialogue of the Bolsheviks with their own commonwealth. This dialogue should to determine the further social development of the USSR. Teachers, local jurisdictions and children should become leaders of the dialogue. The population of the USSR in the early 1920s was predominantly rural. That’s why children were in a traditional family. At such environment, the child didn’t have his own desires, dreams, free time, etc. Parents always involved children to the land work and housekeeping. The Bolsheviks' idea of a school, in which a child would acquire a profession and work, was met with strong resistance among the local population. In the villagers` outlook, the school had to give only reading and elementary grammar. Everything else for existence will be given by the land on which the child must look after. This caused a confrontation between Bolsheviks and local population and fit into the “one-to-one” scheme. Bolsheviks used repression, after the resistance to a unified labor school. Repression meant an attempt to subjugate the traditional population and educate a “new person”. The “other-to-other” scheme also works with respect to the main actors in school life and power. Teachers, as the main leaders of the idea of unified labor school, had to bring up a "new person" locally. But in order to bring up a "new person", must understand what it is and have clear methods of education. The only thing that was clear to the teachers of the 1920s in the USSR – to use work as a tool of education at school. This is not surprising, because the person who chose the profession of а teacher, in the beginning of the Soviet Union, was not intended to educate the generation of communists, but to save their own lives, get benefits and wages, escape from the repression because of own past. That is why, a new generation of teachers consisted of "former" people, such as: White Guards, imperial officers, rich villagers and clergy. These people learned the Soviet language and successfully held posts at the school. It was convenient, but they couldn’t become the leaders of new ideas. So, the project of unified labor school in the USSR in the early 1920s was probably a dialogue or a monologue of Soviet power to the population. School, as a tool of education, became a field of confrontation between different social groups.

DISPOSABLE CAGE AND POT FOR VIRUS TRANSMISSION STUDIES WITH LEAFHOPPERS

1967 ◽  
Vol 99 (7) ◽  
pp. 769-770
Author(s):  
H. P. Richardson ◽  
P. H. Westdal
Keyword(s):  
Virus Transmission ◽  
Rubber Band ◽  
Labour Cost ◽  
Aster Yellows ◽  
Testing Unit ◽  
Transmission Studies ◽  
Made In ◽  
Small Holes ◽  
Air Exchange

The cage and pot described here were used successfully in extensive studies on the transmission of aster yellows virus by the six spotted leafhopper, Macrosteles fascifrons (Stål) (Richardson 1966). The use of this composite unit results in a saving of labour, cost, and greenhouse space.The materials for the testing unit consist of a round peat pot, 3 in. in diameter and 3 in. deep, and a 1-lb polyethylene bag approximately 8 in. long, with an opening 3 in. in diameter. The seedling growing in the pot is covered by the inverted bag and the mouth of the bag is then pulled down over the rim of the pot and secured with a rubber band (Fig. 1). Several hundred small holes are made in the bag to permit air exchange.

Chromospheric activity as a function of age in main-sequence stars

1966 ◽  
Vol 24 ◽  
pp. 40-43
Author(s):  
O. C. Wilson ◽  
A. Skumanich
Keyword(s):  
Main Sequence ◽  
The Sun ◽  
Main Sequence Stars ◽  
Tentative Conclusion ◽  
Chromospheric Activity ◽  
General Field ◽  
Large Clusters

Evidence previously presented by one of the authors (1) suggests strongly that chromospheric activity decreases with age in main sequence stars. This tentative conclusion rests principally upon a comparison of the members of large clusters (Hyades, Praesepe, Pleiades) with non-cluster objects in the general field, including the Sun. It is at least conceivable, however, that cluster and non-cluster stars might differ in some fundamental fashion which could influence the degree of chromospheric activity, and that the observed differences in chromospheric activity would then be attributable to the circumstances of stellar origin rather than to age.

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