scholarly journals Fear of predation shapes social network structure and the acquisition of foraging information in guppy shoals

2017 ◽  
Vol 284 (1867) ◽  
pp. 20172020 ◽  
Author(s):  
Matthew J. Hasenjager ◽  
Lee A. Dugatkin
Keyword(s):  
Social Networks ◽  
High Risk ◽  
Predation Risk ◽  
Poecilia Reticulata ◽  
Risk Groups ◽  
High Background ◽  
Social Network Structure ◽  
Diffusion Analysis ◽  
Spatio Temporal ◽  
Foraging Task

Spatio-temporal variation in predation risk is predicted to select for plastic anti-predator responses, which may in turn impact the fine-scale social structure of prey groups and processes mediated by that structure. To test these predictions, we manipulated the ambient predation risk experienced by Trinidadian guppy ( Poecilia reticulata ) groups before quantifying their social networks and recording individual latencies to approach and solve a novel foraging task. High-risk conditions drove the formation of social networks that were more strongly assorted by body size than those exposed to low ambient risk and promoted longer durations of contact between preferred partners. Additionally, high background predation risk reduced the probability individuals would approach and solve a novel foraging task. Network-based diffusion analysis revealed that while social transmission of the task solution from knowledgeable to naive individuals occurred at a higher rate within low-risk groups, individuals in high-risk groups were particularly likely to investigate the task while shoaling with preferred social partners. Taken together, our results suggest that the structure and functional importance of prey social networks may partly depend on local predation pressure. Furthermore, by influencing individuals' access to information, fear of predation may impact decision-making in a potentially wide array of behavioural contexts.

scholarly journals Sender and receiver experience alters the response of fish to disturbance cues

2019 ◽  
Vol 66 (3) ◽  
pp. 255-261
Author(s):  
Jack A Goldman ◽  
Laurence E A Feyten ◽  
Indar W Ramnarine ◽  
Grant E Brown
Keyword(s):  
Predation Risk ◽  
Poecilia Reticulata ◽  
Laboratory Strain ◽  
Background Risk ◽  
Low Risk ◽  
Response Patterns ◽  
High Background ◽  
Pressure Shaping ◽  
High Predation ◽  
Disturbance Cues

Abstract Predation is a pervasive selection pressure, shaping morphological, physiological, and behavioral phenotypes of prey species. Recent studies have begun to examine how the effects of individual experience with predation risk shapes the use of publicly available risk assessment cues. Here, we investigated the effects of prior predation risk experience on disturbance cue production and use by Trinidadian guppies Poecilia reticulata under laboratory conditions. In our first experiment, we demonstrate that the response of guppies from a high predation population (Lopinot River) was dependent upon the source of disturbance cue senders (high vs. low predation populations). However, guppies collected from a low predation site (Upper Aripo River) exhibited similar responses to disturbance cues, regardless of the sender population. In our second experiment, we used laboratory strain guppies exposed to high versus low background risk conditions. Our results show an analogous response patterns as shown for our first experiment. Guppies exposed to high background risk conditions exhibited stronger responses to the disturbance cues collected from senders exposed to high (vs. low) risk conditions and guppies exposed to low risk conditions were not influenced by sender experience. Combined, our results suggest that experience with background predation risk significantly impacts both the production of and response to disturbance cues in guppies.

Suicide in Nógrád County, Hungary, 1970-1994

Crisis ◽  
1999 ◽  
Vol 20 (2) ◽  
pp. 64-70 ◽  
Author(s):  
Tamás Zonda
Keyword(s):  
High Risk ◽  
Psychiatric Disorders ◽  
Suicide Rate ◽  
Risk Groups ◽  
The Elderly ◽  
Female Ratio ◽  
Suicide Notes ◽  
Suicidal Intention ◽  
Male Female Ratio

The author examined completed suicides occurring over a period of 25 years in a county of Hungary with a traditionally low (relatively speaking) suicide rate of 25.8. The rates are clearly higher in villages than in the towns. The male/female ratio was close to 4:1, among elderly though only 1.5:1. The high risk groups are the elderly, divorced, and widowed. Violent methods are chosen in 66.4% of the cases. The rates are particularly high in the period April-July. Prior communication of suicidal intention was revealed in 16.3% of all cases. Previous attempts had been undertaken by 17%, which in turn means that 83% of suicides were first attempts. In our material 10% the victims left suicide notes. Psychiatric disorders were present in 60.1% of the cases, and severe, multiple somatic illnesses (including malignomas) were present in 8.8%. The majority of the data resemble those found in the literature.

A(H1N1)v cases of the 2009/2010 and 2010/2011 influenza seasons in the Medical and Health Sciences Centre of Debrecen University

2012 ◽  
Vol 153 (17) ◽  
pp. 649-654
Author(s):  
Piroska Orosi ◽  
Judit Szidor ◽  
Tünde Tóthné Tóth ◽  
József Kónya
Keyword(s):  
High Risk ◽  
Influenza Season ◽  
National Level ◽  
Organ Transplant ◽  
High Risk Patient ◽  
Risk Groups ◽  
Health Sciences ◽  
World Health ◽  
Transplant Patients ◽  
Health Organization

The swine-origin new influenza variant A(H1N1) emerged in 2009 and changed the epidemiology of the 2009/2010 influenza season globally and at national level. Aims: The aim of the authors was to analyse the cases of two influenza seasons. Methods: The Medical and Health Sciences Centre of Debrecen University has 1690 beds with 85 000 patients admitted per year. The diagnosis of influenza was conducted using real-time polymerase chain reaction in the microbiological laboratories of the University and the National Epidemiological Centre, according to the recommendation of the World Health Organization. Results: The incidence of influenza was not higher than that observed in the previous season, but two high-risk patient groups were identified: pregnant women and patients with immunodeficiency (oncohematological and organ transplant patients). The influenza vaccine, which is free for high-risk groups and health care workers in Hungary, appeared to be effective for prevention, because in the 2010/2011 influenza season none of the 58 patients who were administered the vaccination developed influenza. Conclusion: It is an important task to protect oncohematological and organ transplant patients. Orv. Hetil., 2012, 153, 649–654.

ON THE ROLE OF BIOMONITORING IN THE ASSESSMENT OF THE HEALTH OF THE POPULATION EXPOSED TO MERCURY

2017 ◽  
pp. 2-7
Author(s):  
L. V. Lukovnikova ◽  
G. I. Sidorin ◽  
L. A. Alikbaeva ◽  
A. V. Galochina
Keyword(s):  
High Risk ◽  
Biological Monitoring ◽  
Clinical Examination ◽  
Inorganic Compounds ◽  
Risk Groups ◽  
Comprehensive Approach ◽  
Chemical Monitoring ◽  
Environmental Objects

When examining the population exposed to organic and inorganic compounds of mercury, a comprehensive approach is proposed, including chemical monitoring of environmental objects, biological monitoring, clinical examination of persons exposed to mercury, identification of high-risk groups.

scholarly journals A Peri-Implant Disease Risk Score for Patients with Dental Implants: Validation and the Influence of the Interval between Maintenance Appointments

2019 ◽  
Vol 8 (2) ◽  
pp. 252 ◽  
Author(s):  
Miguel de Araújo Nobre ◽  
Francisco Salvado ◽  
Paulo Nogueira ◽  
Evangelista Rocha ◽  
Peter Ilg ◽  
...  
Keyword(s):  
High Risk ◽  
Risk Score ◽  
Disease Risk ◽  
Disease Incidence ◽  
Risk Groups ◽  
Risk Profile ◽  
Moderate Risk ◽  
C Statistic ◽  
Disease Risk Score ◽  
Very High

Background: There is a need for tools that provide prediction of peri-implant disease. The purpose of this study was to validate a risk score for peri-implant disease and to assess the influence of the recall regimen in disease incidence based on a five-year retrospective cohort. Methods: Three hundred and fifty-three patients with 1238 implants were observed. A risk score was calculated from eight predictors and risk groups were established. Relative risk (RR) was estimated using logistic regression, and the c-statistic was calculated. The effect/impact of the recall regimen (≤ six months; > six months) on the incidence of peri-implant disease was evaluated for a subset of cases and matched controls. The RR and the proportional attributable risk (PAR) were estimated. Results: At baseline, patients fell into the following risk profiles: low-risk (n = 102, 28.9%), moderate-risk (n = 68, 19.3%), high-risk (n = 77, 21.8%), and very high-risk (n = 106, 30%). The incidence of peri-implant disease over five years was 24.1% (n = 85 patients). The RR for the risk groups was 5.52 (c-statistic = 0.858). The RR for a longer recall regimen was 1.06, corresponding to a PAR of 5.87%. Conclusions: The risk score for estimating peri-implant disease was validated and showed very good performance. Maintenance appointments of < six months or > six months did not influence the incidence of peri-implant disease when considering the matching of cases and controls by risk profile.

scholarly journals SEROPREVALENCE OF LEPTOSPIROSIS IN HIGH RISK GROUPS IN CALICUT, NORTH KERALA, INDIA

2006 ◽  
Vol 24 (4) ◽  
pp. 349-352
Author(s):  
RN Swapna ◽  
U Tuteja ◽  
L Nair ◽  
J Sudarsana
Keyword(s):  
High Risk ◽  
Risk Groups
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