Real-time changepoint detection in a nonlinear expectile model.

An online changepoint detection procedure based on conditional expectiles is introduced. The key contribution is threefold: nonlinearity of the underlying model improves the overall flexibility while a parametric form of the unknown regression function preserves a simple and straightforward interpretation; The conditional expectiles, well-known in econometrics for being the only coherent and elicitable risk measure, introduce additional robustness-especially with respect to asymmetric error distributions common in various types of data; The proposed statistical test is proved to be consistent and the distribution under the null hypothesis does not depend on the functional form of the underlying model nor the unknown parameters. Empirical properties of the proposed real-time changepoint detection test are investigated in a simulation study and a practical applicability is illustrated using the Covid-19 prevalence data from Prague.

Advanced Reconstruction of Vesicourethral Support (ARVUS) during robot-assisted radical prostatectomy: first independent evaluation and review of other factors influencing 1 year continence outcomes.

PURPOSE: Anterior and posterior reconstructions of pelvic structures are used during a robot-assisted radical prostatectomy to obtain better continence outcomes. This study was conducted to evaluate the Advanced Reconstruction of Vesicourethral Support (ARVUS), a novel postprostatectomy reconstruction technique. METHODS: The study was designed as a prospective, controlled, partially randomized and blinded experiment. The statistical analysis was based on the generalized linear modeling (GLM) framework with random effects: the logit link was used to model the probability of achieving continence and the logarithmic link was used to evaluate the overall score of the International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF). The significance of the fixed effects and all possible two-way interactions was tested using the critical level of 0.05. RESULTS: The probability of achieving the continence significantly depends on the neurovascular bundle sparing (p < 0.001) and the time after the surgery (p < 0.001). Analogously, the expected ICIQ-SF score significantly depends on the nerve-sparing status (p = 0.035) and the time after the surgery (p < 0.001). No statistically significant difference between the unilateral or bilateral nerve sparing was found. The ARVUS technique seems to perform slightly worse with respect to the expected continence, but this difference is within the margins of random fluctuations (p = 0.715). CONCLUSIONS: The study demonstrates a significant positive association between the nerve-sparing approach and the patient's continence, however, regardless of the unilateral or bilateral approach. In terms of the continence rate, no statistically significant benefits of ARVUS were observed.

Diel movement of brown trout, Salmo trutta, is reduced in dense populations with high site fidelity.

The movement of individuals within preferred areas is reduced by a high availability of food and information about its distribution, while high number of competitors promotes increased movement. Experienced animals use information about social and physical environment to improve resources exploitation, tended to maintain positions within the preferred areas and reuse the environment that is often referred to as site fidelity. In this study, radio-telemetry was used to observe the movements of 98 adult brown trout, Salmo trutta, in oligotrophic streams with different population densities; to determine subpopulation site fidelity, 5,195 conspecifics from 14 subpopulations were individually tagged during spring and autumn. During a 7-year-long field study, we tested the hypothesis that brown trout individuals from subpopulations with high site fidelity would display lower movement. The hypothesis was supported, and reduced movement was further related to high subpopulation density in association with high slope indicating the physical environment-influenced movement. The probability of contact between individuals increased with subpopulation site fidelity and subpopulation density. No influence of food abundance on brown trout movement was found. Furthermore, increased body size predicted higher movement (and vice versa). The least movement occurred during the day and during the full moons. Our study tended to show that individuals reused preferred areas and needed less movement to exploit available resources.

Ostracism of an albino individual by a group of pigmented catfish.

Physiological and behavioural constraints hinder albino individuals. Albino animals are rare in the wild; this trait is associated with easy detection by predators, non-native or damaged environments, and exclusively aphotic environments in total darkness. The social aspect of albinism is reported only for human beings, and the effect is distinguishable in time and space when social benefits, are used to a limited the extent. Thus far, the social consequences of albinism for animals remain unknown. We used socially established groups of the pigmented catfish, (Silurus glanis), to observe space and temporal distance detachment of albino specimens in laboratory conditions. The albino fish were separated at larger distances from the group than pigmented individuals with the same social status determined by familiarity, and this asymmetry also varied in time. Albinism-related ostracism results in a solitary existence, usually followed by enhanced predation risk. The motivation for an individual's exclusion from a group appears to be the avoidance of the predation risk that increases not only for an odd individual but also for conspecifics within a group. Our findings indicate a role for albinism in behavioural processes related to sociality in a group of conspecifics.