scholarly journals The epidemiology of louping ill in Ayrshire: the first year of studies in sheep

1964 ◽  
Vol 62 (1) ◽  
pp. 53-68 ◽  
Author(s):  
C. E. Gordon Smith ◽  
Dolores A McMahon ◽  
K. J O'Reilly ◽  
A. L Wilson ◽  
J. M Robertson
Keyword(s):  
Neutralizing Antibody ◽  
Early Summer ◽  
Control Measures ◽  
Clinical Disease ◽  
First Year ◽  
Infection Rates ◽  
Long Term Study ◽  
Louping Ill ◽  
The Difference ◽  
Almost All

1. Following an epizootic of louping ill on certain farms in south-west Ayrshire in 1960, a long-term study of several farms was initiated.2. The flocks on two hirsels of one farm were studied during spring and early summer of 1961. Although only one lamb death was confirmed as due to louping ill, the infection rates in sentinel hoggs on the two hirsels were 50–60. and 11% respectively. The difference between the hirsels is probably attributable to the difference in the amount of tick habitat on them.3. The ewes were bled in March and June and their lambs in June. Haemagglutinin inhibition (HI) and neutralization tests revealed that the HI antibody is much shorter lasting than neutralizing antibody. Many ewes, therefore, had neutralizing but not HI antibody. Otherwise agreement between the tests was good. In March almost all the ewes aged 3 years or more had antibody. Of the gimmers (2-year-olds) about two-thirds on one hirsel and one-third on the other had antibody in March: by June almost all the former and about half of the latter had antibody.4. About two-thirds of the lambs had the same antibody status as their mothers in June and almost all the rest had less antibody than their mothers. Serological evidence suggestive of louping ill without recognizable clinical disease was found in six lambs and a further lamb recovered from clinical disease.5. Revaccination of two-thirds of the flock failed to cause any detectable change in antibody status.6. The epidemiology and pathogenesis are discussed in relation to immunity and infection rates, and to the design of control measures.We are greatly indebted to the late Mr James Murdoch at Dalmellington, Mr John Murdoch at Dalcairnie Farm, and Mr David Murdoch at Knockgray Farm for permission to work on their farms and for all the help they gave us during the study.

scholarly journals The role of lambs in louping-ill virus amplification

Parasitology ◽  
2000 ◽  
Vol 120 (2) ◽  
pp. 97-104 ◽  
Author(s):  
M. K. LAURENSON ◽  
R. NORMAN ◽  
H. W. REID ◽  
I. POW ◽  
D. NEWBORN ◽  
...  
Keyword(s):  
Farming Systems ◽  
Early Summer ◽  
Infection Rates ◽  
Force Of Infection ◽  
High Infection ◽  
Louping Ill ◽  
Hill Farming ◽  
The Relationship ◽  
Colostral Antibody

In some areas of Scotland, the prevalence of louping-ill virus has not decreased despite the vaccination of replacement ewes for over 30 years. The role of unvaccinated lambs in viral persistence was examined through a combination of an empirical study of infection rates of lambs and mathematical modelling. Serological sampling revealed that most lambs were protected by colostral immunity at turnout in May/June but were fully susceptible by the end of September. Between 8 and 83% of lambs were infected over the first season, with seroconversion rates greater in late rather than early summer. The proportion of lambs that could have amplified the louping-ill virus was low, however, because high initial titres of colostral antibody on farms with a high force of infection gave protection for several months. A simple mathematical model suggested that the relationship between the force of infection and the percentage of lambs that became viraemic was not linear and that the maximum percentage of viraemic lambs occurred at moderately high infection rates. Examination of the conditions required for louping-ill persistence suggested that the virus could theoretically persist in a sheep flock with over 370 lambs, if the grazing season was longer than 130 days. In practice, however, lamb viraemia is not a general explanation for louping-ill virus persistence as these conditions are not met in most management systems and because the widespread use of acaracides in most tick-affected hill farming systems reduces the number of ticks feeding successfully.

A model of hyperparasite regulation of the gall rust–lodgepole pine pathosystem

1996 ◽  
Vol 26 (7) ◽  
pp. 1256-1265 ◽  
Author(s):  
Bart J. Van Der Kamp ◽  
Peter V. Blenis
Keyword(s):  
Simulation Model ◽  
Environmental Conditions ◽  
Stable Equilibrium ◽  
Mortality Rates ◽  
Control Measures ◽  
First Year ◽  
Infection Rates ◽  
Breeding For Resistance ◽  
Simple Simulation ◽  
Equilibrium Level

Endocronartiumharknessii (J.P. Moore) Hirat. populations never approach the level where all susceptible Pinuscontorta Dougl. ex Loud. var. latifolia Engelm. tissue is infected, even in years when environmental conditions are favourable for infection. A simple simulation model was developed to determine whether a hyperparasite could regulate the rust population and maintain it at an equilibrium level far below host saturation. The model assumed that galls begin sporulating and first become susceptible to parasitism 2 years after formation and requires specification of infection rates for the rust and the hyperparasite, mortality rates for normal and parasitized galls, and the degree to which aeciospore production is reduced following hyperparasite infection. Analysis of the model showed that the hyperparasite could regulate the rust population, producing a stable equilibrium, but only if the various rates were such that healthy galls, in their lifetime, produced enough aeciospores to give rise to more than one new gall, while galls that were parasitized during the first year of aeciospore production produced, in their lifetime, fewer than one new gall. The model of hyperparasite regulation provides one possible explanation of the dynamics of the gall rust pathosystem. It shows that control measures such as sanitation and breeding for resistance may reduce the effectiveness of the hyperparasite in regulating the system and, thus, may fail to achieve the anticipated goals.

scholarly journals Antibody titres in women six to eight years after the administration of RA27/3 and Cendehill rubella vaccines

1978 ◽  
Vol 80 (3) ◽  
pp. 337-347 ◽  
Author(s):  
Helen Macdonald ◽  
J. O'H. Tobin ◽  
J. E. Cradock-Watson ◽  
Joyce Lomax ◽  
M. S. Bourne
Keyword(s):  
Antibody Titre ◽  
Young Women ◽  
Natural Infection ◽  
Neutralizing Antibody ◽  
High Titre ◽  
First Year ◽  
Igm Antibody ◽  
Antibody Titres ◽  
The Difference ◽  
To Come

SummaryTitres of haemagglutination-inhibiting antibody have been measured repeatedly in young women during a period of 6–8 years after the administration of RA27/3 and Cendehill attenuated rubella vaccines. Mean antibody titres were initially 217 after RA27/3 and 159 after Cendehill, but the difference diminished after the first year. Antibody titres were subsequently well maintained in both groups and did not reveal any need for regular revaccination. Mean titres in the Cendehill group were partly maintained by symptomless reinfection which was commoner after Cendehill than after RA27/3. Significant falls in titre were equally common after both vaccines, but low titres of 30 or less were more frequent in subjects who had received Cendehill.Mean neutralizing antibody titres were initially 15·4 after RA27/3 vaccine and 9 after Cendehill. Titres remained higher after RA27/3 for 3 years, but the difference then diminished and became insignificant during the fifth year.Revaccination of women with low antibody titres produced significant increases in 69% of subjects when standard RA27/3 vaccine was used; a special preparation of RA27/3 of higher potency produced a similar number of rises (70%) but elicited higher titres and might occasionally be useful for revaccinating women who are likely to come into contact with rubella. Challenge with RA27/3 vaccine produced weaker responses in women who had experienced natural infection than in those whose antibody was vaccine-induced.Rises in antibody titre after revaccination consisted mainly of IgG, but traces of IgM antibody were detected in one vaccinee who had recently experienced natural reinfection and in 1 woman with naturally acquired antibody who had been challenged with high titre RA27/3 vaccine.

TBE in United Kingdom

2020 ◽  
Keyword(s):  
United Kingdom ◽  
Clinical Disease ◽  
England And Wales ◽  
Probable Case ◽  
The United Kingdom ◽  
South West ◽  
Louping Ill ◽  
The Uk ◽  
North And South ◽  
South West England

Until 2019, TBE was considered only to be an imported disease to the United Kingdom. In that year, evidence became available that the TBEV is likely circulating in the country1,2 and a first “probable case” of TBE originating in the UK was reported.3 In addition to TBEV, louping ill virus (LIV), a member of the TBEV-serocomplex, is also endemic in parts of the UK. Reports of clinical disease caused by LIV in livestock are mainly from Scotland, parts of North and South West England and Wales.4

Transformative Learning in Mastery-Oriented CS0 Course

2021 ◽  
pp. 234763112110072
Author(s):  
Srinivasan Lakshminarayanan ◽  
N. J. Rao ◽  
G. K. Meghana
Keyword(s):  
Transformative Learning ◽  
First Year ◽  
Guided Discovery ◽  
Engineering Programs ◽  
Transformative Experiences ◽  
Significant Difference ◽  
Cognitive Levels ◽  
Almost All ◽  
Core Course

The introductory programming course, commonly known as CS1 and offered as a core course in the first year in all engineering programs in India, is unique because it can address higher cognitive levels, metacognition and some aspects of the affective domain. It can provide much needed transformative experiences to students coming from a system of school education that is dominantly performance-driven. Unfortunately, the CS1 course, as practiced in almost all engineering programs, is also performance-driven because of a variety of compulsions. This paper suggests that the inclusion of a course CS0 can bring about transformative learning that can potentially make a significant difference in the quality of learning in all subsequent engineering courses. The suggested instruction design of this course takes the advantage of the unique features of a course in programming. The proposed CS0 course uses “extreme apprenticeship” and “guided discovery” methods of instruction. The effectiveness of these instruction methods was established through the use of the thematic analysis, a well-known qualitative research method, and the associated coding of transformative learning experiences and instruction components.

39 Managing Burn Wounds with Silvadene

2021 ◽  
Vol 42 (Supplement_1) ◽  
pp. S29-S30
Author(s):  
Tomer Lagziel ◽  
Louis J Born ◽  
Luis H Quiroga ◽  
Eliana Duraes ◽  
Pragna N Shetty ◽  
...  
Keyword(s):  
Length Of Stay ◽  
Wound Infection ◽  
Standard Of Care ◽  
Infection Rates ◽  
Average Amount ◽  
Once Daily ◽  
Preliminary Results ◽  
The Difference ◽  
Dressing Change ◽  
Hospital Acquired

Abstract Introduction Topical delivery of antibacterial agents is typically incorporated and is an essential component of burn wound therapy. The goal is to prevent infection and promote the healing process. Poorly treated wounds can result in scarring or severely in sepsis and multi-organ dysfunction. Topical SSD cream has been the gold-standard for initial local care in partial thickness or full thickness burns. Due to immediate burst release of the drug into the exposed areas, application is relatively frequent (usually twice daily). However, it remains unknown whether twice-daily SSD dressings are superior to once-daily. Methods We maintained a twice-daily dressing change standard of care until 01/01/2019. Patients admitted after that date had their dressing changed once-daily. Our goal is to review outcomes for 75 patients before the change-of-practice and 75 patients after. The main outcomes recorded are wound infection rates, hospital-acquire complications (non-wound related), pain scores, daily narcotic requirements, average amount of SSD used, and length-of-stay. Results Preliminary results of the 75 pre-change-of-practice and 75 post-change-of-practice patients showed slightly better outcomes in the post-change group. Wound-infection rates were the same for both groups (pre=5.33%, post=5.33%), average daily pain-levels for the pre-change group were slightly higher but the difference was negligible and not statistically significant (pre=5.76, post=5.69). The pre-change group had a higher average daily narcotic dosage (pre=6.81mg, post=6.38mg), hospital-acquired complication rates were higher pre-change (pre=10.67%, post=6.67%), and length-of-stay was longer in the pre-change group (pre=10.81, post=9.25). The average amount of SSD jars used per patient was higher as well (pre=6.30, post=2.85). Statistical analysis of the distribution of burn type, age, and burn depth showed no discrepancy and a generalized decreased length-of-stay with once-daily SSD dressing change. Conclusions Preliminary results show that once-daily dressing changes of SSD in burn wounds have no negative impact on wound outcomes. However, it is associated with a decreased length-of-stay, decreased pain levels, and less hospital-acquired complications. A decreased length-of-stay means reduced medical expenses for the patient and the hospital. In addition, less hospital-acquired complications result in better patient recovery. Since the difference in wound outcomes is negligible and statistically insignificant, changing the standard-of-care to once-daily could prove beneficial.

scholarly journals Field Efficacy of Steinernema sp. (Rhabditida: Steinernematidae) on the Colorado Potato Beetle Overwintering Generation

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1464
Author(s):  
Maja Čačija ◽  
Renata Bažok ◽  
Majda Kolenc ◽  
Tena Bujas ◽  
Zrinka Drmić ◽  
...  
Keyword(s):  
Colorado Potato Beetle ◽  
First Generation ◽  
Control Measures ◽  
Recommended Dose ◽  
Steinernema Feltiae ◽  
First Year ◽  
Potato Beetle ◽  
Field Efficacy ◽  
Second Year ◽  
Economic Pest

Colorado potato beetle (CPB) is an economic pest of potato that has developed resistance to all classes of chemical insecticides, thus requiring alternative control measures. As a potential solution, entomopathogenic nematodes (EPNs) have proven effective in suppressing this pest, but their efficacy against overwintering generations of CPB in Croatia has not been sufficiently researched. The aim of this two-year (2018–2019) field study was to determine the efficacy of Steinernema feltiae and Steinernema carpocapsae applied to overwintering CPB adults. EPNs were applied at three doses (7.5 mil./10 m2, 5.0 mil./10 m2 (the recommended dose) and 2.5 mil./10 m2) by watering the soil where the adults were overwintering. The first-year results were satisfactory for both EPNs: the efficacy of S. feltiae ranged from 79.03% to 100.00%, while the efficacy of S. carpocapsae ranged from 77.32% to 96.22%. In the second year, the highest efficacy (69.57%) was obtained using the recommended dose of S. feltiae. Although the results are not consistent across the two years of our study and suggest further research, they indicate that EPNs have great potential in controlling overwintering CPB generations to reduce first generation abundance and damage, and also to prevent the spread of new generations to surrounding potato growing areas.

scholarly journals The Effect of Vaccination Rates on the Infection of COVID-19 under the Vaccination Rate below the Herd Immunity Threshold

2021 ◽  
Vol 18 (14) ◽  
pp. 7491
Author(s):  
Yi-Tui Chen
Keyword(s):  
Infection Rate ◽  
Herd Immunity ◽  
The United States ◽  
Vaccination Rate ◽  
Infection Rates ◽  
Vaccination Rates ◽  
The United Kingdom ◽  
The World ◽  
Almost All ◽  
The Impact

Although vaccination is carried out worldwide, the vaccination rate varies greatly. As of 24 May 2021, in some countries, the proportion of the population fully vaccinated against COVID-19 has exceeded 50%, but in many countries, this proportion is still very low, less than 1%. This article aims to explore the impact of vaccination on the spread of the COVID-19 pandemic. As the herd immunity of almost all countries in the world has not been reached, several countries were selected as sample cases by employing the following criteria: more than 60 vaccine doses per 100 people and a population of more than one million people. In the end, a total of eight countries/regions were selected, including Israel, the UAE, Chile, the United Kingdom, the United States, Hungary, and Qatar. The results find that vaccination has a major impact on reducing infection rates in all countries. However, the infection rate after vaccination showed two trends. One is an inverted U-shaped trend, and the other is an L-shaped trend. For those countries with an inverted U-shaped trend, the infection rate begins to decline when the vaccination rate reaches 1.46–50.91 doses per 100 people.

A Long-Term Study of What Best Predicts Graduating From University Versus Leaving Prior to Graduation

2021 ◽  
pp. 152102512098799
Author(s):  
Teena Willoughby ◽  
Victoria W. Dykstra ◽  
Taylor Heffer ◽  
Joelle Braccio ◽  
Hamnah Shahid
Keyword(s):  
Mental Health ◽  
Social Engagement ◽  
Retention Rates ◽  
First Year ◽  
Long Term Study ◽  
Enrollment Status ◽  
Mental Health Difficulties ◽  
University Degree ◽  
The University

Despite the importance of obtaining a university degree, retention rates remain a concern for many universities. This longitudinal study provides a multi-domain examination of first-year student characteristics and behaviors that best predict which students graduate. Graduation status was assessed seven years after students entered university. Participants (N = 1017; 71% female; mean age in Year 1 was 19 years) enrolled in a Canadian mid-sized university completed a survey, provided their enrollment status over the next 6 years (regardless of whether they left university), and consented to have their grades and status provided by the Registrar. Overall, 79% of students graduated by Year 7 (44% in 4 years). The strongest predictor of graduation was first-year grades. Social engagement in the university also predicted graduation. Surprisingly, mental health was not a significant predictor of graduation. Only a minority of students may experience mental health difficulties to such an extent that it affects their ability to succeed at university.

scholarly journals High COVID-19 transmission potential associated with re-opening universities can be mitigated with layered interventions

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ellen Brooks-Pollock ◽  
Hannah Christensen ◽  
Adam Trickey ◽  
Gibran Hemani ◽  
Emily Nixon ◽  
...  
Keyword(s):  
Prediction Interval ◽  
Mitigation Strategies ◽  
Control Measures ◽  
Transmission Model ◽  
Model Parameters ◽  
Infection Rates ◽  
First Year Students ◽  
Transmission Potential ◽  
Plausible Model ◽  
Effective Option

AbstractControlling COVID-19 transmission in universities poses challenges due to the complex social networks and potential for asymptomatic spread. We developed a stochastic transmission model based on realistic mixing patterns and evaluated alternative mitigation strategies. We predict, for plausible model parameters, that if asymptomatic cases are half as infectious as symptomatic cases, then 15% (98% Prediction Interval: 6–35%) of students could be infected during the first term without additional control measures. First year students are the main drivers of transmission with the highest infection rates, largely due to communal residences. In isolation, reducing face-to-face teaching is the most effective intervention considered, however layering multiple interventions could reduce infection rates by 75%. Fortnightly or more frequent mass testing is required to impact transmission and was not the most effective option considered. Our findings suggest that additional outbreak control measures should be considered for university settings.

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