Artificial Termite-Fishing Tasks as Enrichment for Sanctuary-Housed Chimpanzees: Behavioral Effects and Impact on Welfare

Artificial termite-fishing tasks are a common enrichment for captive great apes, promoting species-typical behaviors. Nonetheless, whether these activities are linked to changes in other behaviors and whether these changes persist over time has seldom been investigated. We assessed whether the use of an artificial termite-fishing task was linked to changes in the solitary behavior and social dynamics in two groups of sanctuary-housed chimpanzees (Pan troglodytes). Specifically, we compared chimpanzee behavior during eight enrichment sessions distributed over a two-month period, with similar periods before and after the introduction of the enrichment. Data were collected from combined interval and continuous sampling methods and were analyzed using generalized linear mixed models. We found that participation increased across sessions and that both enrichment and participation predicted an increase in tool use and feeding and a decrease in inactivity, which were all maintained throughout the sessions. Furthermore, participation was positively associated with social proximity, revealing a gathering effect of the task. However, neither enrichment nor participation were linked to changes in abnormal, self-directed, affiliation-related or aggression-related behaviors. Overall, our results support the hypothesis that artificial termite-fishing is a suitable enrichment for captive chimpanzees, maintaining the subjects’ interest and promoting species-typical behaviors, with no negative effects on social activities.

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l2-Penalized temporal logit-mixed models for the estimation of regional obesity prevalence over time

Statistical Methods in Medical Research ◽

10.1177/09622802211017583 ◽

2021 ◽

pp. 096228022110175

Author(s):

Jan P Burgard ◽

Joscha Krause ◽

Ralf Münnich ◽

Domingo Morales

Keyword(s):

Parameter Estimation ◽

Medical Treatment ◽

Mixed Models ◽

Generalized Linear Mixed Models ◽

Linear Mixed Models ◽

Obesity Prevalence ◽

Model Parameter ◽

Model Parameter Estimation ◽

Public Health Reporting ◽

Over Time

Obesity is considered to be one of the primary health risks in modern industrialized societies. Estimating the evolution of its prevalence over time is an essential element of public health reporting. This requires the application of suitable statistical methods on epidemiologic data with substantial local detail. Generalized linear-mixed models with medical treatment records as covariates mark a powerful combination for this purpose. However, the task is methodologically challenging. Disease frequencies are subject to both regional and temporal heterogeneity. Medical treatment records often show strong internal correlation due to diagnosis-related grouping. This frequently causes excessive variance in model parameter estimation due to rank-deficiency problems. Further, generalized linear-mixed models are often estimated via approximate inference methods as their likelihood functions do not have closed forms. These problems combined lead to unacceptable uncertainty in prevalence estimates over time. We propose an l2-penalized temporal logit-mixed model to solve these issues. We derive empirical best predictors and present a parametric bootstrap to estimate their mean-squared errors. A novel penalized maximum approximate likelihood algorithm for model parameter estimation is stated. With this new methodology, the regional obesity prevalence in Germany from 2009 to 2012 is estimated. We find that the national prevalence ranges between 15 and 16%, with significant regional clustering in eastern Germany.

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Impact of COVID-19 Lockdown on Serie A Soccer Players’ Physical Qualities

International Journal of Sports Medicine ◽

10.1055/a-1345-9262 ◽

2021 ◽

Author(s):

Ermanno Rampinini ◽

Federico Donghi ◽

Marco Martin ◽

Andrea Bosio ◽

Marco Riggio ◽

...

Keyword(s):

Aerobic Fitness ◽

Mixed Models ◽

Peak Power ◽

Vertical Jump ◽

Soccer Players ◽

Limited Evidence ◽

Professional Soccer ◽

Home Based ◽

Before And After ◽

Different Seasons

AbstractIn March 2020, the COVID-19 pandemic forced most activities in Italy, including soccer, to cease. During lockdown, players could only train at home, with limited evidence regarding the effect of this period. Therefore, this study aimed to investigate the effect of COVID-19 lockdown on professional soccer players’ physical performance. Aerobic fitness and vertical jump were assessed before and after four periods in two different seasons: COVID-19 lockdown, competitive period before lockdown, competitive period and summer break of the 2016–2017 season. Linear mixed models were used to examine within-period changes and between-period differences in changes observed during COVID-19 lockdown and the three other periods. Within-period changes in aerobic fitness showed a significant improvement following COVID-19 lockdown (p<0.001) and a significant decline during summer break (p<0.001). Between-period differences were significant in the comparison of COVID-19 lockdown with both the competitive 2019–2020 season (p<0.01) and summer break (p<0.001). For the vertical jump, only the between-period comparison revealed significant differences as the changes associated with COVID-19 lockdown were worse than those of the two competitive periods, for both absolute (p<0.05; p<0.001) and relative peak power (p<0.01; p<0.001). Home-based training during lockdown was effective to improve aerobic fitness, although it did not allow players to maintain their competitive period’s power levels.

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A coefficient of determination (R2) for generalized linear mixed models

Biometrical Journal ◽

10.1002/bimj.201800270 ◽

2019 ◽

Cited By ~ 3

Author(s):

Hans‐Peter Piepho

Keyword(s):

Mixed Models ◽

Generalized Linear Mixed Models ◽

Linear Mixed Models ◽

Coefficient Of Determination

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Spatial generalized linear mixed models with multivariate CAR models for areal data

Spatial Statistics ◽

10.1016/j.spasta.2014.05.001 ◽

2014 ◽

Vol 10 ◽

pp. 12-26 ◽

Cited By ~ 7

Author(s):

Mahmoud Torabi

Keyword(s):

Mixed Models ◽

Generalized Linear Mixed Models ◽

Linear Mixed Models ◽

Areal Data

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Node-Splitting Generalized Linear Mixed Models for Evaluation of Inconsistency in Network Meta-Analysis

Value in Health ◽

10.1016/j.jval.2016.07.005 ◽

2016 ◽

Vol 19 (8) ◽

pp. 957-963 ◽

Cited By ~ 21

Author(s):

Tu Yu-Kang

Keyword(s):

Mixed Models ◽

Generalized Linear Mixed Models ◽

Meta Analysis ◽

Linear Mixed Models ◽

Node Splitting

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Reconsidering Taíno Social Dynamics after Spanish Conquest: Gender and Class in Culture Contact Studies

American Antiquity ◽

10.2307/4128440 ◽

2004 ◽

Vol 69 (4) ◽

pp. 597-626 ◽

Cited By ~ 49

Author(s):

Kathleen Deagan

Keyword(s):

Native Americans ◽

Social Practice ◽

Social Dynamics ◽

Analytical Framework ◽

Cultural Practice ◽

Culture Contact ◽

Contact Period ◽

Cultural Elements ◽

Mitigating Factors ◽

Before And After

Despite the fact that the Taíno people of the Caribbean were the first Native Americans to encounter and coexist with Europeans after 1492, there has been almost no archaeology of Taíno response to that encounter. This study explores the reasons for (and consequences of) this neglect, and their larger implications for American contact-period archaeology. It also challenges prevailing historical models of Taíno social disintegration, drawing upon six years of archaeological work at the En Bas Saline site in Haiti, the only extensively excavated Taíno townsite occupied both before and after contact. Our results, organized by a household-scale analytical framework emphasizing Taíno constructions of gender and class, suggest that there were few major alterations to traditional Taíno social practice during the post-contact period, and most of these were related to activities thought to have been the domain of non-elite Taíno men. It is suggested that the relatively nonspecialized gender roles among the Taíno, as well as the clearly differentiated nature of their social classes, may have served as mitigating factors in the disruption of Taíno cultural practice under Spanish domination. This work also reveals a marked Taíno resistance to the incorporation of European cultural elements, which provides a striking contrast to the Spanish patterns documented in contact-era European towns, and underscores the critical importance of incorporating gender relations into studies of culture contact.

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