Short-term Encounters Research Articles

Non-single dating app use and the cognitive and psychological mechanisms of infidelity: gender differences

The increasing prevalence of dating apps has reshaped the dynamics of romantic relationships, with many users already in committed partnerships. However, the link between encountering a large pool of potential alternatives and predicting current relationship outcomes, particularly infidelity and possible gender differences, has not been fully explored. Drawing on the investment model framework, this study examines the cognitive and psychological mechanisms underlying online and offline infidelity tendencies among dating app users in relationships. Data from non-single dating app users in Taiwan reveal a positive relationship between the quantity and quality of alternatives, suggesting that exposure to many profiles may prompt users to rely on heuristics and focus on distinctive characteristics to quickly assess potential alternatives. Furthermore, having many choices may satisfy the need for short-term encounters. The quality of alternatives is positively linked to partner choice regret, which negatively impacts commitment. Gender differences emerge, with males showing a higher likelihood of infidelity due to partner choice regrets, particularly in offline contexts. Despite maintaining a strong commitment to their primary partner, males exhibit a greater inclination towards offline infidelity, highlighting a scenario where commitment and infidelity may coexist for male dating app users. Theoretical implications of digital matchmaking in contemporary relationships are discussed.

Short-Term Effects of Ambient Air Pollution on Chronic Obstructive Pulmonary Disease Admissions in Jiuquan, China.

Recent findings indicate that air pollution contributes to the onset and advancement of chronic obstructive pulmonary disease (COPD). Nevertheless, there is insufficient research indicating that air pollution is linked to COPD in the region of inland northwest China. Daily hospital admission records for COPD, air pollutant levels, and meteorological factor information were collected in Jiuquan for this study between 1 January 2018 and 31 December 2019. We employed a distributed lag non-linear model (DLNM) integrated with the generalized additive model (GAM) to assess the association between air pollution and hospital admissions for COPD with single lag days from lag0 to lag7 and multiday moving average lag days from lag01 to lag07. For example, the pollutant concentration on the current day was lag0, and on the prior 7th day was lag7. The present and previous 7-day moving average pollutant concentration was lag07. Gender, age, and season-specific stratified analyses were also carried out. It is noteworthy that the delayed days exhibited a different pattern, and the magnitude of associations varied. For NO2 and CO, obvious associations with hospitalizations for COPD were found at lag1, lag01-lag07, and lag03-lag07, with the biggest associations at lag05 and lag06 [RR = 1.015 (95%CI: 1.008, 1.023) for NO2, RR = 2.049 (95%CI: 1.416, 2.966) for CO], while only SO2 at lag02 was appreciably linked to hospitalizations for COPD [1.167 (95%CI: 1.009, 1.348)]. In contrast, short-term encounters with PM2.5, PM10, and O3 were found to have no significant effects on COPD morbidity. The lag effects of NO2 and CO were stronger than those of PM2.5 and PM10. Males and those aged 65 years or older were more vulnerable to air pollution. When it came to the seasons, the impacts appeared to be more pronounced in the cold season. In conclusion, short-term encounters with NO2 and CO were significantly correlated with COPD hospitalization in males and the elderly (≥65).

Multi-maneuver algorithms for multi-risk collision avoidance via nonconvex quadratic optimization

In this article, the problem of modeling and computing the optimal collision avoidance maneuvers for multiple short-term encounters is presented. Several metrics defining the overall collision risk are analyzed. These include imposing lower bounds on the miss-distance or the Mahalanobis distance at each corresponding time of closest approach (TCA) or upper-bounds on the collision probability. The avoidance maneuvers are modeled as impulsive ones in a single direction of the local frame and for a priori fixed dates for operational motivations. Station-keeping constraints are also imposed via linear inequalities on the relative states at each TCA. The specific nature of the imposed constraints is dictated by a practical framework provided by the French Space Agency (CNES). This results in formulating the maneuver design problem as an optimization problem with linear objective and non-convex quadratic constraints. Different algorithms are presented to solve this problem. Finally, the relative efficiency of the proposed approaches is evaluated and analyzed on a realistic conjunction built from data extracted from the CNES database and on academic random examples of higher complexity.

Low-Thrust Collision Avoidance Maneuver Optimization

This work presents robust and numerically efficient algorithms for designing low-thrust collision avoidance maneuvers in short-term encounters. The conjunction dynamics are developed in a tridimensional space and then projected onto the B-plane, centered at the secondary object. Energy- and fuel-optimal maneuvers are computed by constraining the collision probability or the miss distance. A fully analytical approach is derived for energy-optimal collision avoidance maneuvers, providing a good guess for the fuel-optimal problem. The proposed methods are validated in terms of efficiency and robustness in a simulated scenario accounting for environmental perturbations.

Short-Term Collision Probability Algorithm for Parallelepiped-Shaped Satellites

The probability of collision of two solid satellites, one of which is a parallelepiped and the other is a parallelepiped or a small sphere, is computed under the assumptions of short-term encounter. The probability is given by the integral of the relative position probability density over a region of the collision plane. This region is the Minkowski sum of the projections of the objects’ shapes onto the collision plane. The integration is the only step that cannot be done analytically. When the position probability densities are Gaussians, a very fast and accurate algorithm found in the literature can be applied after several transformations have been performed to the integration region. A comparison against several current methods has been included. When a parallelepiped is involved, the presented method is advantageous with respect to the existing ones.

Rapid Field Research: How Short-Term Encounters in the Field Deliver Intense, Rapid Routes to Knowin

Inductive field researchers are all too familiar with the ‘long march’. Slow and steady, researchers dive deep into the field to explore a complex phenomenon in a holistic fashion. In this paper, we call for more rapid, intense routes to knowing. A rapid approach is particularly needed to address disruptions and crises situations such as the Covid-19 pandemic in ‘real time’ or phenomena that may be only fleeting or captured in transient episodes of organizational life. By drawing on an idiographic logic, we offer a rapid field research approach which places an emphasis on a demarcated phenomenon in intense short-term encounters in the field that afford a deeper understanding in ‘real time’. We develop three core principles for rapid field research, namely ‘perceptive researcher’, ‘sensemaking in the field’, and ‘selectivity in telling the story’. We conduct a review of rapid ethnography studies in medical education and health research. Through this synthesis, we characterize the tenets of field research, which have the quality of intensity to support a rapid approach (demarcating the research focus, strategies for data intensity, simultaneous data collection and analysis, rapid writing). Our study considers the implications of valorising a rapid route to knowing for horizontal knowledge accumulation and revisits the requisite skills and professional norms of writing and publishing that may enable this rapid approach.

Collision avoidance maneuver optimization with a multiple-impulse convex formulation

A method to compute optimal collision avoidance maneuvers for short-term encounters is presented. The maneuvers are modeled as multiple-impulses to handle impulsive cases and to approximate finite burn arcs associated either with short alert times or the use of low-thrust propulsion. The maneuver design is formulated as a sequence of convex optimization problems solved in polynomial time by state-of-the-art primal–dual interior-point algorithms. The proposed approach calculates optimal solutions without assumptions about the thrust arc structure and thrust direction. The execution time is fraction of a second for an optimization problem with hundreds of variables and constraints, making it suitable for autonomous calculations.

The Function of Casual Sex Action and Inaction Regret: A Longitudinal Investigation.

In several recent papers the sex difference in regret predicted by sexual strategies theory has been supported: men more than women report regret passing up short-term sexual opportunities (inaction regret), while women regret having had sexual encounters (action regret). However, the adaptive function of regret, to improve future behavioral choices, has not been tested. In this first longitudinal test of behavioral change following regret, we consider whether regret actually results in adaptive shifts of behavior: will men who regret passing up sex engage in more short-term sex following regret? Will women who regret short-term encounters either choose better quality partners, reduce number of one-night stands or shift their strategy to long-term relationships? Across two waves (NT1 = 399, 65.4% women and NT2 = 222, 66.2% women) students responded to questions about casual sex action regret and inaction regret, along with possible outcomes, intrapersonal traits, and concurrent contextual predictors. There was no clear evidence for the proposed functional shifts in sexual behavior. Casual sex regret was associated with respondent sex and stable individual differences, such as sociosexual attitudes, regret processing and metacognitions, but the effect of these predictors were not consistent across the two waves. Among the tested concurrent contextual predictors, sexual disgust was the most consistent across waves. Regret is considered a gauge of the value and quality of the short-term sexual encounter. However, tentatively we conclude that after this first test of function using longitudinal data, we find no evidence of a mating strategy shifting effect following sexual regret.

Exposure to particulate matter and carbon monoxide and cause-specific Cardiovascular-Respiratory disease mortality in Ahvaz

Recently the short term effects of air pollutants on cardiovascular and respiratory morbidity and mortality has attracted the attention of many researchers. This study comprehensively examined the association between short-term exposure to particulate matter (PM) and carbon monoxide (CO), on non-accidental mortality, and mortality due to respiratory, cardiovascular, and cerebrovascular diseases. Daily death and air pollutants data including PM10, PM2.5, and CO from 2008 to 2017 was inquired. A time-series study using modified linear distributed lag models, combined with quasi-Poisson regression was conducted for evaluating the effect of pollutants on mortality up to 7 days lag; adjusted for day of the week, temperature and relative humidity. A significant and direct relation was seen between PM2.5 and non-accidental, and respiratory deaths. For every 10 /m3 increase in PM2.5, the risk of non-accidental deaths increased 0.1% after 2 and 6 days lag, and the risk of respiratory deaths increased 0.4% after 5 days lag. Also, for every 10 /m3 increase in PM10, hypertension related death increased 0.2% after 4 days lag. Ultimately, for every 10 /m3 increase in CO, hypertension related death increased 30.5%, ischemic heart disease deaths increased 21.1%, and cerebrovascular disease related deaths increased 42.6%; after 7, 1, and 4 days lag respectively. Short-term encounter with PM and CO is associated with increased mortality. Urban and rural residents should avoid polluted air especially during dust storms. More serious air pollution control is needed in Ahvaz.

Fast and Accurate Computation of Orbital Collision Probability for Short-Term Encounters

This article provides a new method for computing the probability of collision between two spherical space objects involved in a short-term encounter under Gaussian-distributed uncertainty. In this model of conjunction, classical assumptions reduce the probability of collision to the integral of a two-dimensional Gaussian probability density function over a disk. The computational method presented here is based on an analytic expression for the integral, derived by use of Laplace transform and D-finite functions properties. The formula has the form of a product between an exponential term and a convergent power series with positive coefficients. Analytic bounds on the truncation error are also derived and are used to obtain a very accurate algorithm. Another contribution is the derivation of analytic bounds on the probability of collision itself, allowing for a very fast and, in most cases, very precise evaluation of the risk. The only other analytical method of the literature (based on an approximation) is shown to be a special case of the new formula. A numerical study illustrates the efficiency of the proposed algorithms on a broad variety of examples and favorably compares the approach to the other methods of the literature.

An empirical study of short-term encounter group as a training returnable type

An empirical study of short-term encounter group as a training returnable type

Effects of encounters with fish on activity of sedentary benthic invertebrates

Most experiments on effects of anti-predator behaviours use small enclosures and study behaviour and development of prey in the constant and immediate presence of predators. While useful, such studies are difficult to relate to natural situations where prey and predators are unrestricted. We describe a system designed specifically to estimate the impact of fish on foraging of larval Chironomus tentans under field levels of encounters with fish. The system involves raceways designed to control movement of fish over patches of chironomids so the impact of realistic, short-term encounters between predators and prey could be measured. Fish passes significantly reduced foraging activity, but the reduction was small (median of 1.16 min-fish event−1 · larvae−1, or 6.5% of the time normally spent active) and did not depend on larval hunger nor fish size or species. Other laboratory experiments using large wading pools indicated 15 cm was the best estimate of the distance over which larvae respond to fish. We estimated foraging time lost in the field as frequency of encounter with fish (estimated from video recordings of fish traffic in 2 lakes) multiplied by time lost per encounter (estimated from laboratory studies). The most realistic estimates suggest larvae in the lakes would reduce their foraging time by 4–16% as a result of interactions with fish. Results suggest traditional techniques might overestimate the effects of predators on behaviour of prey.

Theory successfully predicts hiding time: new data for the lizard Sceloporus virgatus and a review

Economic hypotheses predict that prey in refuges after short-term encounters with predators decide how long to hide before emerging (hiding time) based on cost of emerging (predation risk) and cost of not emerging. Here, I report tests of predictions of these hypotheses for several cost of emerging and cost of remaining in refuge factors in the lizard Sceloporus virgatus by approaching lizards to elicit refuge entry, review tests of the predictions to evaluate the success of current models in predicting hiding time, and note parallels between models predicting hiding time and flight initiation distance (distance separating predator from prey when escape begins). Hiding times were longer under greater risk implied by faster, more direct, and repeated approaches and by greater proximity of the predator to the refuge during hiding. Lizards responded to costs of refuge use by emerging sooner when food was visible outside and when the refuge was substantially cooler than the lizard. In addition, lizards were more likely to enter refuges when approached rapidly and when cloudiness precluded effective thermoregulation by basking. Review of findings for lizards and other taxa revealed strong support for the predictions of cost-benefit models that hiding time increases with cost of emerging and decreases with cost of staying in refuge. Examination of parallel predictions by escape theory and refuge use theory emphasizes their fundamental similarity and led to identification of an untested prediction of refuge use theory. Key words: emergence time, escape theory, hiding time, predation risk, refuge use, Squamata, thermal cost. [Behav Ecol]

Fleeing and hiding under simultaneous risks and costs

Prey evaluate risk implied by a predator during its approach, intrinsic prey features, and environmental factors to weigh risk against costs. Most studies of escape and hiding time in refuge focus on a single factor, but prey that ignore other factors may soon be dead. Two hypotheses make different predictions about additivity versus interaction of risk–cost factors. The risksensitivity hypothesis predicts that multiple factors have additive effects, but optimality theory suggests that interaction is more common. In the only previous study, flight initiation distance (FID ¼ predator–prey distance when escape begins) was affected interactively by 2 risk factors (predator approach speed and directness) but additively by a risk and an escape cost (approach speed and food presence). I predicted that effects of approach speed and other risk factors interact because differences in risk are likely to increase more rapidly with increase in approach speed than other factors. FID by lizards that I approached increased interactively with approach speed and directness in the Sceloporus virgatus and speed and predator persistence in Sceloporus jarrovii. During indirect approaches, fewer S. virgatus fled, and they ran shorter distances. A review of effects of multiple risks and costs on FID and hiding time revealed far more frequent interactive than additive effects between 2 risk factors, as predicted by optimality theory. Additive and interactive effects were equally common between a risk and a cost factor. Findings for some factors differ between FID and hiding time and in other ways. I propose hypotheses to explain some differences. Key words: escape behavior, flight initiation distance, hiding time, refuge use, squamata. [Behav Ecol] P rey must cope with predation risk posed by predators that vary in many ways relevant to escape decisions, as well as assess environmental factors and intrinsic prey characteristics affecting risk. Prey that can evaluate multiple risks simultaneously should have higher long-term survival than prey that react to only a single factor. Experiments on escape behavior usually examine effects of single risk factors and control others, but it may be anticipated that many prey can take into account multiple risk factors operating during short-term encounters with predators. Prey able to respond to multiple risks might treat them additively or interactively (Smith and Belk 2001). Studies bearing on this issue for pairs of risk factors or factors affecting risk and cost of escaping or hiding (lost opportunities) are limited to lizards and turtles. Although information is beginning to accumulate about effects of simultaneous risk on escape behavior (Table 1), conditions leading to additivity or interaction between the factors are poorly understood. Escape theory predicts flight initiation distance (FID ¼ distance between predator and prey when escape begins) and sometimes distance fled based on risks and costs (Ydenberg and Dill 1986; Cooper and Frederick 2007a). Predictions are made from expected fitness determined jointly by multiple factors that affect predation risk and escape cost. Without knowledge of the form of functions relating fitness to distance between predator and prey, escape theory does not predict whether effects are additive or interactive.

Hormonal Responses to Aggression Vary in Different Types of Agonistic Encounters in Male Tree Lizards, Urosaurus ornatus

Hormonal responses to male-male interactions have been detected in some studies of vertebrates but not others. One hypothesis that may partially explain these discrepancies is that differences in the duration of male-male interactions cause different hormonal responses. In social systems based on dominance-subordinance hierarchies interactions often last longer than if exclusive territories are maintained. Tests of the hypothesis that encounter duration explains discrepancies in hormonal responses would be facilitated by a species that shows elements of both types of social systems, such as species in which males practice alternative reproductive tactics. We compared plasma levels of corticosterone and testosterone in males of the territorial morph of the tree lizard (Urosaurus ornatus) subjected either to short (15 min) male-male encounters or to long (7 days) dominance interactions. In the long interactions, dominant males had lower levels of corticosterone than did subordinate males over the first day, but this difference subsequently disappeared. In sharp contrast, winners of short-term encounters had elevated plasma corticosterone levels which peaked the day after the encounter. Thus, males isolated after a short encounter experienced an increase in corticosterone that was apparently inhibited in males who continued interacting with other males. The delayed increase in corticosterone after a short encounter may facilitate metabolic recovery from the encounter, mobilize metabolic substrates useful in subsequent encounters, or may alter subsequent behavior. The response does not appear to be simply recovery from exercise because in a second experiment males exercised for 15 min did not show a similar delayed increase in corticosterone the following day. Testosterone levels were also monitored and did not change in any of these treatments. These results demonstrate that the duration and the outcome of male-male interactions may each independently influence hormone levels.

A dual status-signalling system: a matter of redundancy or differing roles?

Abstract. Some populations of tree lizards, Urosaurus ornatus, are polymorphic for throat (gular) coloration. In these populations, males with blue or green throats tend to dominate males with less blue/green (more orange) throats during short-term encounters. In other populations, where males are monomorphic with respect to throat coloration, males may signal 'high' (dominant) status by turning very dark dorsally. Month-long experiments conducted in semi-natural outdoor pens determined that males from a polymorphic population, which are rarely seen to darken in the wild, are capable of dorsal darkening. Also, these males signalled dominant status by dorsal darkening when throat coloration of all males in the group was the same. Consequently, a second set of month-long experiments tested the hypothesis that dorsal darkening is rarely seen in the field because the throat signal takes precedence over the dorsal signal when throat coloration differs among males. The results do not support this hypothesis. Furthermore, there was no correlation between male throat coloration and dominance status in these experiments. Thus, dorsal darkening is not merely a back-up signal when the throat colour of the contestant males is the same. It may serve, instead, as a long-distance dominance signal when population density is high.

Working with People: How to Set Limits When a Patient Demands Too Much

What should you do when you feel angry with a patient or don't like him? Is it OK to let patients know how you feel? Most of us become uncomfortable when we experience strong negative feelings toward patients. We withdraw or try to avoid the person. While this response may work in short-term encounters, the nurse-patient relationship demands that we solve, not ignore, the problem. In working with sick people daily, it becomes easy to take for granted the profound impact illness has on people. Most patients feel very vulnerable and are frightened by their dependence on us. They perceive our distancing or avoidance as abandonment. They will do whatever it takes to counteract our behavior, to keep us involved. Thus, if we do not deal with our dislike of a patient, we set up a situation where a patient must yell to get our attention. Should we try to ignore our angry feelings and force ourselves to be pleasant? Again, this response isn't appropriate. First, difficult patients are, on some level, aware of how they are affecting others and don't trust an unrealistic smiling response. Instead, they may worry that you are

Gender and helping behavior: A meta-analytic review of the social psychological literature.

Contends, on the basis of posited social-role theory of gender and helping, that the male gender role fosters helping that is heroic and chivalrous, whereas the female gender role fosters helping that is nurturant and caring. In social psychological studies, helping behavior has mainly been examined in the context of short-term encounters with strangers. This focus has tended to exclude from the research literature those helping behaviors prescribed by the female gender role, because they are displayed primarily in long-term, close relationships. In contrast, the helping behaviors prescribed by the male gender role have been generously represented in research findings because they are displayed in relationships with strangers as well as in close relationships. Results from a meta-analytic review of sex differences in 172 studies (appended) in helping behavior indicate that in general men helped more than women and women received more help than men. Nevertheless, sex differences in helping were inconsistent across studies and were successfully predicted by various attributes of the studies and the helping behaviors. (96 ref) (PsycInfo Database Record (c) 2022 APA, all rights reserved).