Zebrafish Neighbor Distance Changes Relative to Conspecific Size, Position in the Water Column, and the Horizon: A Video-Playback Experiment

Many fish form schools and maintain visual contact with their neighbors in a three-dimensional environment. In this study, we assessed whether zebrafish modified their spacing and interaction time in an additive or multiplicative way relative to multiple sources of social information using computer animations. We simultaneously manipulated: (a) the size of the virtual conspecific (as a proxy of social cue magnitude), (b) the position of the virtual conspecific in the water column (as a proxy of the level of perceived risk), and (c) the absence/presence of the visual horizon (as a proxy of depth perception). We found that the size of the virtual conspecific independently affected spacing behavior (zebrafish increased their separation distance as conspecific size increased). However, some of these factors interacted significantly, such that their effects on social behavior depended on each other. For instance, zebrafish increased their separation distance under high risk conditions when the virtual conspecific was larger, but this risk effect disappeared when the conspecific was the same size or smaller, likely to avoid aggression. Also, zebrafish increased their separation distance when depth perception was enhanced under low risk conditions, but the effect of depth perception disappeared under high risk conditions. Overall, we found that certain dimensions of the visual social environment affected zebrafish spacing behavior in different ways, but they did not affect social interaction time. We discuss the implications of these findings for the spatial organization of fish schools.

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The visual social environment affects non-additively neighbor spacing and interaction time in zebrafish

10.1101/511972 ◽

2019 ◽

Author(s):

Diana Pita ◽

Esteban Fernández-Juricic

Keyword(s):

Spatial Organization ◽

Separation Distance ◽

Social Cues ◽

Low Risk ◽

Interaction Time ◽

Social Risk ◽

Depth Effect ◽

3D Environment ◽

Spacing Behavior ◽

The Social

AbstractMany fish form schools and visually track the position of their neighbors in a 3D environment. In this study, we assessed whether zebrafish modified their spacing behavior and interaction time in an additive or multiplicative way relative to multiple sources of visual social information using video playbacks. We simultaneously manipulated: (a) the magnitude of the social cues (by varying the size of the virtual fish), (b) the level of social risk (low, high based on the position of the virtual fish in the water column), and (c) the perceived depth of the social cues (visual horizon absent or present). Each of these factors independently affected spacing behavior (zebrafish increased the separation distance with larger virtual fish, under lower visual social risk, and when depth perception was enhanced), but they did not affect interaction time. However, some of these factors interacted significantly, such that their effects on social behavior depended on each other. For instance, zebrafish decreased their separation distance under high vs. low risk conditions when the virtual fish was the same or smaller size, but this risk effect disappeared with larger virtual fish likely to avoid aggression. Also, zebrafish increased their separation distance when perceived depth was enhanced under low risk, but the perceived depth effect became less pronounced under high risk probably due to dilution effects. Overall, the effects of certain visual social parameters depend on the intensity of other visual social parameters, ultimately tuning up or down different social behavioral responses. We discuss the implications for the spatial organization of fish schools.Significance StatementMany fish form schools and visually track the position of their neighbors in a 3D environment. We found that zebrafish consider multiple visual social sources of information simultaneously to modify their neighbor distance. Thus, their spacing behavior appears to follow multiplicative rules, whereby the spacing response to a visual social parameter depend on the intensity of a different visual social parameter.

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Cross-cultural adaptation of the Perceived Risk of HIV Scale in Brazilian Portuguese

Health and Quality of Life Outcomes ◽

10.1186/s12955-021-01760-6 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Thiago S. Torres ◽

Paula M. Luz ◽

Luana M. S. Marins ◽

Daniel R. B. Bezerra ◽

Celline C. Almeida-Brasil ◽

...

Keyword(s):

High Risk ◽

Risk Behaviors ◽

Cultural Adaptation ◽

Perceived Risk ◽

Brazilian Portuguese ◽

Cross Cultural ◽

Key Populations ◽

Cross Sectional ◽

High Risk Behaviors ◽

Cross Cultural Adaptation

Abstract Background Valid and reliable instruments are needed to measure the multiple dimensions of perceived risk. The Perceived Risk of HIV Scale is an 8-item measure that assesses how people think and feel about their risk of infection. We set out to perform a cross-cultural adaptation of the scale to Brazilian Portuguese among key populations (gay, bisexual and other men who have sex with men and transgender/non-binary) and other populations (cisgender heterosexual men and cisgender women). Methods Methodological study with cross-sectional design conducted online during October/2019 (key populations [sample 1] and other populations) and February–March/2020 (key populations not on pre-exposure prophylaxis [sample 2]). Cross-cultural adaptation of the Perceived Risk of HIV Scale followed Beaton et al. 2000 guidelines and included confirmatory factor analysis, differential item functioning (DIF) using the Multiple-Indicator Multiple-Cause model, and concurrent validity to verify if younger individuals, those ever testing for HIV, and engaging in high-risk behaviors had higher scores on the scale. Results 4342 participants from key populations (sample 1 = 235; sample 2 = 4107) and 155 participants from other populations completed the measure. We confirmed the single-factor structure of the original measure (fit indices for sample 1 plus other populations: CFI = 0.98, TLI = 0.98, RMSEA = 0.07; sample 2 plus other populations: CFI = 0.97, TLI = 0.95, RMSEA = 0.09). For the comparisons between key populations and other populations, three items (item 2: “I worry about getting infected with HIV”, item 4: “I am sure I will not get infected with HIV”, and item 8: “Getting HIV is something I have”) exhibited statistically significant DIF. Items 2 and 8 were endorsed at higher levels by key populations and item 4 by other populations. However, the effect of DIF on overall scores was negligible (0.10 and 0.02 standard deviations for the models with other populations plus sample 1 and 2, respectively). Those ever testing for HIV scored higher than those who never tested (p < .001); among key populations, those engaging in high-risk behaviors scored higher than those reporting low-risk. Conclusion The Perceived Risk of HIV Scale can be used among key populations and other populations from Brazil.

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Predicting reattendance at a high-risk breast cancer clinic

Palliative & Supportive Care ◽

10.1017/s1478951515000164 ◽

2015 ◽

Vol 13 (5) ◽

pp. 1441-1448 ◽

Cited By ~ 3

Author(s):

Sarah R. Ormseth ◽

David K. Wellisch ◽

Adam E. Aréchiga ◽

Taylor L. Draper

Keyword(s):

Breast Cancer ◽

High Risk ◽

Perceived Risk ◽

Depressive Symptomatology ◽

High Risk Breast Cancer ◽

High Risk Breast ◽

Risk Breast Cancer ◽

Cancer Clinic ◽

High Risk Clinic

AbstractObjective:The research about follow-up patterns of women attending high-risk breast-cancer clinics is sparse. This study sought to profile daughters of breast-cancer patients who are likely to return versus those unlikely to return for follow-up care in a high-risk clinic.Method:Our investigation included 131 patients attending the UCLA Revlon Breast Center High Risk Clinic. Predictor variables included age, computed breast-cancer risk, participants' perceived personal risk, clinically significant depressive symptomatology (CES–D score ≥ 16), current level of anxiety (State–Trait Anxiety Inventory), and survival status of participants' mothers (survived or passed away from breast cancer).Results:A greater likelihood of reattendance was associated with older age (adjusted odds ratio [AOR] = 1.07, p = 0.004), computed breast-cancer risk (AOR = 1.10, p = 0.017), absence of depressive symptomatology (AOR = 0.25, p = 0.009), past psychiatric diagnosis (AOR = 3.14, p = 0.029), and maternal loss to breast cancer (AOR = 2.59, p = 0.034). Also, an interaction was found between mother's survival and perceived risk (p = 0.019), such that reattendance was associated with higher perceived risk among participants whose mothers survived (AOR = 1.04, p = 0.002), but not those whose mothers died (AOR = 0.99, p = 0.685). Furthermore, a nonlinear inverted “U” relationship was observed between state anxiety and reattendance (p = 0.037); participants with moderate anxiety were more likely to reattend than those with low or high anxiety levels.Significance of Results:Demographic, medical, and psychosocial factors were found to be independently associated with reattendance to a high-risk breast-cancer clinic. Explication of the profiles of women who may or may not reattend may serve to inform the development and implementation of interventions to increase the likelihood of follow-up care.

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An Exploration of Perceived Risk and Willingness to Try New Products

Journal of Marketing Research ◽

10.1177/002224376700400405 ◽

1967 ◽

Vol 4 (4) ◽

pp. 368-372 ◽

Cited By ~ 21

Author(s):

Donald T. Popielarz

Keyword(s):

High Risk ◽

Cognitive Style ◽

Perceived Risk ◽

New Products ◽

Willingness To Accept ◽

Consumer Decisions ◽

The Relationship

Consumer decisions about new products are generally recognized as potentially high risk situations. This article explores as a dimension of cognitive style the relationship between willingness to try new products and willingness to accept different forms of risk. Data suggest that cognitive style relates to trying new products.

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Comparison of Cardiovascular Disease Risks of Actual and Perceptions of Men’s that 40-65 Years Old

European Journal of Public Health ◽

10.1093/eurpub/ckz187.066 ◽

2019 ◽

Vol 29 (Supplement_4) ◽

Author(s):

İbrahim Topuz ◽

Sebahat Gozum

Keyword(s):

Blood Pressure ◽

Cardiovascular Disease ◽

High Risk ◽

Perceived Risk ◽

Risk Perceptions ◽

Smoking Status ◽

Cvd Risk ◽

Related Factors ◽

Risk Reducing ◽

Very High

Abstract Background Turkey is among the top countries in Europe in coronary mortality in the 45-74 age range. The highest death due to disorders of the circulatory system (50.8%) that is Amasya province. Objective Determine related factors and to compare with actual and perceived cardiovascular disease (CVD) risks of men aged 40-65 living in Amasya. Methods The sample size of cross-sectional and analytical study consisted of 400 people who met the inclusion criteria. Actual CVD risks of men were calculated using HeartScore. Age, systolic blood pressure, total cholesterol measured by blood taken from the capillary and smoking status were used to calculate CVD risk. Actual CVD risk in next decade has been calculated as low, medium, high or very high. Perceived CVD risk in next decade were identified by participants as low, medium, high and very high responses. They also questioned why evaluation of perceived risk. Results It was determined whereas 8.3% of the males had high, 52.5% had a very high level of CVD risk. The main variables affecting actual CVD risk; diastolic blood pressure, BMI and physical activity. 13.3% of males perceived CVD risks at high and 8% at very high. The main variables affecting perceived CVD risk; age and DM. It was found that 48% and 23.8% of males perceived CVD risks lower and higher than actual CVD risk while 28.2% were accurate. Those who perceived CVD risk at a moderate, high and very high think that this is caused by diseases that increase the risk of CVD and smoking. Conclusions Approximately 1/2 men has very high risk of CVD. It was determined that 1/2 men perceived risks are lower with false optimism and couldn’t accurately identify risks of people older and with diabetes. Key messages It can be ensured that develop risk reducing behaviors and individuals with high risk of CVD can raise their awareness. The risk perceptions of males in the very high-risk group from the past to the present are important because they affect their actual risks and risk-reducing behaviors.

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Accident History and Perceived Risk of Injury as Factors Influencing Fatalism about Occupational Accidents

Perceptual and Motor Skills ◽

10.1177/003151259508100260 ◽

1995 ◽

Vol 81 (2) ◽

pp. 665-666 ◽

Cited By ~ 2

Author(s):

W. Andrew Harrell

Keyword(s):

High Risk ◽

Perceived Risk ◽

Occupational Accidents ◽

Personal Injury ◽

Men And Women ◽

Factors Influencing ◽

Risk Of Injury ◽

Workplace Accidents

In a survey of 263 employed men and women fatalism about workplace accidents was rated highest by respondents who perceived that their current jobs were dangerous and posed a high risk of personal injury. An individual's prior accident history was not associated with ratings on Accident Fatalism.

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Some Environmental Considerations of Electrical Power Generation From Ocean Currents in the Straits of Florida

Solar Energy ◽

10.1115/isec2005-76252 ◽

2005 ◽

Cited By ~ 1

Author(s):

Charles W. Finkl ◽

Roger Charlier ◽

Erin Hague

Keyword(s):

Water Column ◽

Transmission Lines ◽

Electrical Power ◽

Separation Distance ◽

Ocean Currents ◽

Ocean Current ◽

Benthic Habitat ◽

Florida Current ◽

Large Area ◽

Straits Of Florida

Ocean currents contain a remarkable amount of kinetic energy and have potential worldwide capability. Initial tests to harness current power focus on the Straits of Florida where the Florida Current has a total flow capacity of about 30 × 106 m3 s−1. Generation of clean electricity from ocean currents off southeast Florida is based on a power extractor comprised by open-center turbine technology. This innovative turbine provides safe passage for fish and other aquatic species. The water-column array of energy production units (EPUs) will have a 350 km2 footprint, based on a 600 m (10 rotor diameters) downstream separation distance between EPUs with a lateral separation of 400 m. Water depths for the EPU field are in the range of 100 to 500 m. With such a large area of water column and benthic habitat utilized, environmental concerns must be overcome, including routing of transmission lines to shore. Risks and vulnerabilities of the proposed ocean current generated electricity include failure of individual EPUs and damage to sensitive coastal marine environments during installation.

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1630. Voluntary HIV Testing and Self-Realization of Risk of HIV Infection Among Young Men-Who-Have-Sex-with-Men in the Miami-Dade Area

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz360.1494 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S595-S595

Author(s):

Hampton Ocon ◽

Samir Sabbag

Keyword(s):

Public Health ◽

High Risk ◽

Hiv Infection ◽

Hiv Testing ◽

Hiv Risk ◽

Perceived Risk ◽

Health Initiatives ◽

History Of ◽

Sex With Men ◽

Public Health Initiatives

Abstract Background According to the Centers for Disease Control and Prevention, Miami-Dade County has the highest rate of new HIV diagnoses in the Nation. So far, a large focus of public health initiatives has been spreading awareness of HIV testing locations, but this form of voluntary testing relies on individuals realizing that they are at risk of HIV infection in the first place. Consequently, a major obstacle to encouraging young men-who-have-sex-with-men (YMSM) to test themselves for HIV is their own self-perceived risk of having an undetected infection. Methods In an effort to better understand the discordance between high-risk sexual behavior and HIV testing among this high-risk population, YMSM (18–24) were surveyed through smartphone applications that facilitate sexual encounters in the Miami-Dade area (eg Grindr, Scruff). Users were asked about their history of condomless anal intercourse (CAI), their HIV testing habits, and whether or not they believe it possible that they are currently infected with HIV. An analysis of the relationship between CAI and self-perception of possible HIV infection was performed using Cochran-Mantel–Haenszel testing. Results Of the 843 eligible responses, 667 reported a history of voluntary HIV testing while 176 had never voluntarily tested. 726 respondents reported a history of CAI and 131 of these have never voluntarily tested. Of the 843 total participants, 1.6% were in the highest HIV risk group, which is those who have engaged in CAI with an exchange/casual partner, have never voluntarily tested for HIV, and have no self-perceived risk of being currently infected. According to data analysis, YMSM who have engaged in CAI but have never been tested for HIV were not more likely to have a self-perceived possibility of infection when compared with those who have voluntarily tested (P < 0.595). Conclusion This suggests that many high-risk YMSM are not voluntarily testing themselves for HIV not because they do not have access to testing, but rather because they do not perceive themselves as being possibly infected in the first place. Therefore, in addition to increasing access to HIV testing, new public health initiatives must be designed to facilitate YMSM understanding their own personal HIV risk. Disclosures All authors: No reported disclosures.

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