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Social learning-learning from others-is the basis for behavioural traditions. Different social learning strategies (SLS), where individuals biasedly learn behaviours based on their content or who demonstrates them, may increase an individual's fitness and generate behavioural traditions. While SLS have been mostly studied in isolation, their interaction and the interplay between individual and social learning is less understood. We performed a field-based open diffusion experiment in a wild primate. We provided two groups of vervet monkeys with a novel food, unshelled peanuts, and documented how three different peanut opening techniques spread within the groups. We analysed data using hierarchical Bayesian dynamic learning models that explore the integration of multiple SLS with individual learning. We (1) report evidence of social learning compared to strictly individual learning, (2) show that vervets preferentially socially learn the technique that yields the highest observed payoff and (3) also bias attention toward individuals of higher rank. This shows that behavioural preferences can arise when individuals integrate social information about the efficiency of a behaviour alongside cues related to the rank of a demonstrator. When these preferences converge to the same behaviour in a group, they may result in stable behavioural traditions. published

Contains fulltext : 286889.pdf (Publisher’s version ) (Open Access) BACKGROUND: Thrombosis is a frequent and severe complication in patients with coronavirus disease 2019 (COVID-19) admitted to the intensive care unit (ICU). Lupus anticoagulant (LA) is a strong acquired risk factor for thrombosis in various diseases and is frequently observed in patients with COVID-19. Whether LA is associated with thrombosis in patients with severe COVID-19 is currently unclear. OBJECTIVE: To investigate if LA is associated with thrombosis in critically ill patients with COVID-19. PATIENTS/METHODS: The presence of LA and other antiphospholipid antibodies was assessed in patients with COVID-19 admitted to the ICU. LA was determined with dilute Russell's viper venom time (dRVVT) and LA-sensitive activated partial thromboplastin time (aPTT) reagents. RESULTS: Of 169 patients with COVID-19, 116 (69%) tested positive for at least one antiphospholipid antibody upon admission to the ICU. Forty (24%) patients tested positive for LA; of whom 29 (17%) tested positive with a dRVVT, 19 (11%) tested positive with an LA-sensitive aPTT, and 8 (5%) tested positive on both tests. Fifty-eight (34%) patients developed thrombosis after ICU admission. The odds ratio (OR) for thrombosis in patients with LA based on a dRVVT was 2.5 (95% confidence interval [CI], 1.1-5.7), which increased to 4.5 (95% CI, 1.4-14.3) in patients at or below the median age in this study (64 years). LA positivity based on a dRVVT or LA-sensitive aPTT was only associated with thrombosis in patients aged less than 65 years (OR, 3.8; 95% CI, 1.3-11.4) and disappeared after adjustment for C-reactive protein. CONCLUSION: Lupus anticoagulant on admission is strongly associated with thrombosis in critically ill patients with COVID-19, especially in patients aged less than 65 years.

By studying the behavior of nonhuman primates, particularly in wild settings, researchers have been able to investigate a range of cognitive abilities, shedding light on the evolution of certain aspects of cognition and revealing potential evolutionary precursors of many capacities considered uniquely human. Vervet monkeys (Chlorocebus pygerythrus) have been widely investigated due to their prevalence and their suitability for experimental testing in the wild with an ecologically valid approach that is not possible with many other primates, especially apes. Here we review advances in the understanding of a number of cognitive and behavioral processes that have been gleaned from studies conducted with wild vervet monkeys over the past half century, primarily focusing on social cognitive abilities. We direct our attention to three major areas of study; communication, cooperation and trade, and social learning. We discuss how findings from this species have contributed (and continue to contribute) to our understanding of the evolution of human cognitive capacities and suggest future avenues of research with this species.

In recent decades, an accelerating research effort has exploited a substantial diversity of methodologies to garner mounting evidence for social learning and culture in many species of primate. As in humans, the evidence suggests that the juvenile phases of non-human primates' lives represent a period of particular intensity in adaptive learning from others, yet the relevant research remains scattered in the literature. Accordingly, we here offer what we believe to be the first substantial collation and review of this body of work and its implications for the lifetime behavioral ecology of primates. We divide our analysis into three main phases: a first phase of learning focused on primary attachment figures, typically the mother; a second phase of selective learning from a widening array of group members, including some with expertise that the primary figures may lack; and a third phase following later dispersal, when a migrant individual encounters new ecological and social circumstances about which the existing residents possess expertise that can be learned from. Collating a diversity of discoveries about this lifetime process leads us to conclude that social learning pervades primate ontogenetic development, importantly shaping locally adaptive knowledge and skills that span multiple aspects of the behavioral repertoire.

PhD (Human Movement Science), North-West University, Potchefstroom Campus Perseptueel-motoriese bevoegdheid is belangrik vir kinders se algehele ontwikkeling. Dit dra veral by tot hulle kognitiewe ontwikkeling en speel gevolglik 'n belangrike rol in hul akademiese prestasie op skoolvlak. Verskeie rolspelers beïnvloed perseptueel-motoriese bevoegdheid, sowel as akademiese prestasie, waar sommiges buite die beheer van die kind is (bv. sosio-ekonomiese status, die skoolomgewing, en onderwysers se kennis), terwyl ander rolspelers weer hoofsaaklik van toepassing is op onderliggende vermoëns waaroor die kind beskik, en motoriese vaardighede, visuele persepsie, uitvoerende funksie, fisieke fiksheid en liggaamsamestelling onder andere insluit. Hierdie proefskrif is op vier doelstellings gebaseer, waarvan die eerste twee doelstellings slegs op ontledings van graad 7-leerders van toepassing is, terwyl doelstelling drie en vier longitudinale ontledings van die volle tydperk van sewe skooljare waaroor die studie gestrek het, ingesluit het. Eerstens was ten doel om die mate waartoe verskillende funksionele visueel-perseptuele konstrukte wat onderverdeel word in basiese, opeenvolgings- en komplekse vaardighede, se invloede op akademiese prestasie van graad 7-leerders in die Noordwes Provinsie van Suid-Afrika, te bepaal. Tweedens het die studie ten doel gehad om die invloed van uitvoerende funksies, soos onderverdeel in werksgeheue, uitvoerende funksie en inhiberingsbeheer, op akademiese prestasie van graad 7-leerders in die Noordwes Provinsie van Suid-Afrika te bepaal. Die derde doel was om die langdurige invloed van lae sosio-ekonomiese status, soos geïdentifiseer by graad 1-leerders, op die verband tussen hul vroeë perseptueel-motoriese bevoegdheid en akademiese prestasie in graad 7 in die Noordwes Provinsie van Suid-Afrika te bepaal. Laastens was die doel om te bepaal wat die langdurige invloed van obesiteit, soos geïdentifiseer by graad 1-leerders, op die verband tussen hulle vroeë perseptueel-motoriese bevoegdheid en hulle akademiese prestasie in graad 7 in die Noordwes Provinsie van Suid-Afrika sal wees. Die studie het gebruik gemaak van verskeie proefgroepsamestellings binne die North-West Child Health, Integrated with Learning and Development (NW-CHILD) longitudinale studie. Dié studie het oor die hele laerskooltydperk van sewe jaar gestrek en het proefpersone afkomstig van Kwintiel 1- tot Kwintiel 5-skole, vanuit 20 verskillende skole in vier skooldistrikte in die Noordwes Provinsie van Suid-Afrika ingesluit. Proefpersone is ewekansig gekies en het longitudinaal deelgeneem aan 'n basislyntoetsing in graad 1 (2010, N=816) en twee opvolgmetings in graad 4 (2013) en graad 7 (2016), onderskeidelik. Verskillende geslagte (seuns en dogters), rasse (wit, swart, Indiër en ander), en sosio-ekonomiese statusgroepe (hoog en laag) is by die gestratifiseerde ewekansige NW-CHILD populasiesamestelling ingesluit. Vir die doeleindes van die betrokke studie is sosio-ekonomiese skoolstatus as 'n proksie vir kategorisering van sosio-ekonomiese status gebruik. Doelstelling een het gebruik gemaak van 'n dwarsdeursnit-studieontwerp binne die longitudinale NW-CHILD studie en het 518 proefpersone met 'n gemiddelde ouderdom van 12.92 jaar (±0.42) ingesluit, waarvan 51.98% seuns was, 48.02% dogters, 74.70% swart, en 25.30% wit. Die ondersoekgroep het ook proefpersone vanaf lae (59.55%) en hoë sosio-ekonomiese status-skole (40.45%) ingesluit. Proefpersone se basiese, opeenvolgings- en komplekse visueel-perseptuele vaardighede is met die Test of Visual Perceptual Skills, derde uitgawe (TVPS-3) vasgestel, terwyl hul akademiese prestasie bepaal is deur 'n provinsiale assessering (Noordwes Provinsiale Assessering [NWPA]) en die Junie-skoolassessering van die betrokke skole. Vir doeleindes van die tweede doelstelling is slegs twee van die vier skooldistrikte wat deel uitmaak van die NW-CHILD studie, as 'n subpopulasie geselekteer waar 272 (12.95 jaar, ±0.40) proefpersone deel van die ondersoekgroep uitgemaak het, waarvan 54.41% seuns was, en 45.58% dogters. Die proefpersoongroep het verder ook uit verskillende rasse (77.21% swart en 22.79% wit) en sosio-ekonomiese status-groepe (58.46% laag en 41.54% hoog) bestaan. Uitvoerende funksie vermoë, verdeel in werksgeheue, uitvoerende funksie en inhiberingsbeheer, is bepaal deur gebruik te maak van die Tower of London, tweede uitgawe (TOLDX-2). Akademiese prestasie is weereens vasgestel deur provinsiale (NWPA) en Junie-skoolassesserings. Doelstellings drie en vier het al die proefpersone betrek wat in 2010, 2013 en 2016 aan die metings deelgeneem het en gevolglik oor volledige datastelle beskik het (N=381). Die geslagsverspreiding binne die groep was redelik gelyk (seuns 47.51%, dogters 52.49%), terwyl rasgroepe 'n aanvaarbare verteenwoordiging van Suid-Afrika se bevolkingsdemografie was (swart 72.70%, wit 27.30%), en proefpersone uit hoë (42.78%) en lae (57.22%) sosio-ekonomiese status-skole, deel van die ondersoekgroep uitgemaak het. Akademiese prestasie in graad 1, 4 en 7 is bepaal deur punte wat tydens die provinsiale (JNA en NWPA) en skoolassesserings behaal is, te analiseer. Perseptueel-motoriese bevoegdheid is vasgestel deur gebruik te maak van die Bruininks Oseretsky Test of Motor Proficiency Short Form, tweede uitgawe (BOT-2 SF), asook drie volledige subkomponente van die BOT-2, naamlik krag, balans en hardloopspoed en ratsheid. Addisioneel tot reedsgenoemde metings vir doelstellings drie en vier, is proefpersone se liggaamsmassa-indeks (LMI) ook vir doelstelling vier bereken en is die proefpersone op grond van gestandaardiseerde norme van ontledingsdoeleindes in vier LMI-kategorieë geplaas. Die vier LMI-kategorieë het nooit-oorgewig-; normaal-na-oorgewig-; altyd-oorgewig-; en oorgewig-na-normaal-groepe ingesluit. Statistiese analises vir doelstellings een en twee was soortgelyk en die Statistica-rekenaarprogram is gebruik om die data te analiseer (Statsoft, 2017). Om die verbande tussen onderskeidelik verskillende funksionele visueel-perseptuele konstrukte en akademiese prestasie, en uitvoerende funksies en akademiese prestasie te bepaal is gebruik gemaak van Spearman Rangorde korrelasiekoëffisiënte (r). Vir uitvoerende funksie is 'n Pearson korrelasie-analise (r) verder uitgevoer om vir die effek van sosio-ekonomiese status op bogenoemde analise te kontroleer. Geslag-, ras- en sosio-ekonomiese statusverskille is in beide doelstellings ontleed deur onafhanklike T-toetsing, waar p≤0.05 as 'n statisties-betekenisvolle maatstaf gebruik is, en hierdie verskille opgevolg is met praktiese betekenisvolheid, waar d-waardes gelyk aan 0.2 (klein), 0.5 (medium), en 0.8 (groot) as prakties-betekenisvolle verskille aanvaar is. Vir doelstellings drie en vier is 'n Spearman Rangordekorrelasie-analise (r) uitgevoer om eerstens te bepaal of daar 'n verband tussen vroeë perseptueel-motoriese bevoegdheid en latere akademiese prestasie bestaan (Statsoft, 2017). Akademiese en perseptueel-motoriese bevoegdheidsverskille en veranderinge tussen die verskillende sosio-ekonomiese groepe (hoog en laag) en verskillende liggaamsmassa- indeks-kategorieë (altyd-oorgewig, oorgewig-na-normaal, nooit-oorgewig, normaal-na-oorgewig) is longitudinaal ondersoek deur gebruik te maak van 'n latente groeikurwe-analise binne 'n strukturele vergelykingsmodel (Structural Equation Modeling/SEM) raamwerk (AMOS, weergawe 25). Die SEM-analise is verder gebruik om die langdurige invloed van onderskeidelik sosio-ekonomiese status en oorgewig/obesiteit op die verband tussen vroeë perseptueel-motoriese bevoegdheid en latere akademiese prestasie te bereken. Die resultate wat behaal is met betrekking tot doelstelling een het getoon dat basiese, opeenvolgings-, sowel as komplekse visueel-perseptuele vaardighede die akademiese prestasie van graad 7-leerders op twaalfjarige ouderdom betekenisvol beïnvloed het. Betekenisvolle korrelasies is tussen basiese visueel-perseptuele prosesse (veral ruimtelike verhoudings) en die eerste addisionele taal (r=0.33; r=0.30), wiskunde (r=0.32), sowel as die graadpuntgemiddeldes (r=0.41; r=0.40), tydens onderskeidelik die skool- en provinsiale assesserings gevind. Visueel-perseptuele opeenvolgingsprosesse het statisties-betekenisvolle korrelasies van slegs klein praktiese betekenisvolheid met tale, wiskunde en die graadpuntgemiddeld getoon (r=0.14 tot r=0.28). Komplekse visueel-perseptuele prosesse het matig gekorreleer met die eerste addisionele taal (r=0.33) en die graadpuntgemiddeld tydens die provinsiale (r=0.39), en die skoolassessering (r=0.40). Die twee komplekse visueel-perseptuele vaardighede, naamlik figuuragtergrond-diskriminasie (r=0.34) en visuele sluiting (r=0.36), het ook betekenisvol met die graadpunt- gemiddeldes tydens die Junie-skoolassessering gekorreleer. Die resultate behaal met betrekking tot doelstelling twee dui daarop dat sekere uitvoerende funksies ook in graad 7, op twaalfjarige ouderdom, akademiese prestasie betekenisvol beïnvloed. Uitvoerende funksie en inhiberingsbeheer het onderskeidelik statisties-betekenisvolle korrelasies van klein praktiese betekenisvolheid met tale (r=0.12; r=0.13), wiskunde (r=0.15; r=0.12) en graadpuntgemiddeldes (r=0.14; r=0.14) tydens beide die assesseringsgeleenthede getoon. Werksgeheue (beplanning- en probleemoplossingsvaardighede) het egter nie met akademiese prestasie van graad 7-leerders gekorreleer nie. Nadat daar vir sosio-ekonomiese status se invloede gekontroleer is, het slegs inhiberingsbeheer (r=0.14) statisties betekenisvol met wiskundeprestasie in graad 7 gekorreleer. Die SEM-modelle wat ontwikkel is met betrekking tot doelstellings drie en vier het beide oor goeie passingsmaatstawwe volgens statistiese vereistes beskik (CFI = 0.873, 0.879 en 0.864, 0.868; CMIN/DF = 3.983, 4.289 en 3811, 4.093; RMSEA = 0.089, 0.093 en 0.086, 0.090). Die resultate het betekenisvolle invloede op die verband tussen perseptueel-motoriese bevoegdheid en akademiese prestasie getoon, met akademiese grondslag (0.380; 0.386) en goeie perseptueel-motoriese vermoëns in graad 1 (0.149; 0.208), wat getoon het om belangrik te wees vir akademiese prestasie in graad 4 (0.653; 0.799) en gevolglik ook in graad 7. Seuns (-0.237; -0.256), en leerders uit lae sosio-ekonomiese omstandighede (-0.463; -0.576) het volgens die ontleding van doelstelling drie ook akademies swakker presteer. Lae sosio-ekonomiese status het akademiese prestasie gedurende graad 1, 4 en 7 negatief beïnvloed, terwyl oorgewig- en obese leerders in die ontleding van doelstelling vier akademiesgewys betekenisvol beter gevaar het as leerders in die ander LMI-kategorieë (nooit-oorgewig, normaal-na-oorgewig en oorgewig-na-normaal). Uit die studie het dit geblyk dat oorgewig en obesiteit die perseptueel-motoriese bevoegdheid van laerskoolleerders benadeel, hoewel oorgewig, soos geïdentifiseer in graad 1, nie op die lange duur hulle akademiese prestasie negatief beïnvloed het nie. Beter akademiese prestasie het veral tydens graad 1 en graad 4 in die oorgewiggroepe voorgekom, alhoewel hierdie verskille teen graad 7 hoofsaaklik nie meer beduidend was nie en ook nie die verband tussen perseptueel-motoriese bevoegdheid en akademiese prestasie op die lang duur beïnvloed het nie. Ander rolspelers soos sosio-ekonomiese status was eerder beduidend vir akademiese prestasie teen graad 7. Op grond van bogenoemde bevindinge word die gevolgtrekking gemaak dat vroeë perseptueel-motoriese bevoegdheid 'n betekenisvolle rol in latere akademiese prestasie speel en dat lae sosio-ekonomiese status tot 'n groot mate beide perseptueel-motoriese bevoegdheid en akademiese prestasie regdeur die laerskoolloopbaan negatief beïnvloed. Hierdie gevolgtrekking lei tot die aanbeveling dat perseptueel-motoriese bevoegdheid reeds vanaf 'n jong ouderdom beklemtoon moet word deurdat dit op 'n ouderdomsgepaste wyse deur kundiges ontwikkel moet word, weens die bevestigde verband met latere akademiese prestasie. Daar word ook aanbeveel dat leerders uit lae sosio-ekonomiese areas spesiale aandag ontvang in terme van addisionele akademiese hulp, blootstelling aan visueel-perseptuele en uitvoerende funksie-ervarings, asook ouderdomsgepaste perseptueel-motoriese ontwikkeling, om die nadelige effek van lae sosio-ekonomiese status op akademiese prestasie te minimaliseer. Sosio-ekonomiese status het deurgaans invloede getoon op akademiese prestasie wat verdere strategieë vanuit verskillende oorde en vanaf belanghebbendes noodsaak om hierdie negatiewe effekte op kinders se akademiese vordering te probeer minimaliseer. Oorgewig het geblyk om wel perseptueel-motoriese bevoegdheid op die lange duur negatief te affekteer, hoewel dit nie akademiese prestasie negatief beïnvloed het nie. Die agteruitgang wat gevind is in oorgewig leerders se perseptueel-motoriese vaardighede vereis wel voorkomende strategieë, aangesien dit later in hul lewens akademiese prestasie negatief kan beïnvloed of tot fisieke onaktiwiteit kan bydra, wat kan lei tot gepaardgaande negatiewe gesondheidsgevolge. Doctoral

Behavioural variation in primates has been well studied at the level of individuals by behavioural ecologists, and more recently at a population level by cultural biologists. Behavioural differences between groups of the same population, however, have rarely been considered. Here, I review intergroup variation in universally occurring behaviours between up to six neighbouring groups of vervet monkeys. Group differences have been found in several domains including foraging, conflicts, grooming and proximity. An exclusively ecological explanation for the observed variation appears implausible, as these monkey groups have overlapping home ranges, and their ecology is therefore very similar. The presence of a genetic bias underlying the observed group differences is also implausible, as males disperse between groups at sexual maturity and multiple times within their lives creating a continuous gene flow between the six groups. This leaves socially learned group-level traditions as the most plausible explanation. I discuss ways in which this working conclusion can be tested. The likely presence of group-level traditions in close proximity, well known in humans, has rarely been considered for non-human primates and adds an important dimension to research on conformity in non-human cultures.

The validity of each new cardiac output (CO) monitor should be established before implementation in clinical practice. For this purpose, method comparison studies investigate the accuracy and precision against a reference technique. With the emergence of continuous CO monitors, the ability to detect changes in CO, in addition to its absolute value, has gained interest. Therefore, method comparison studies increasingly include assessment of trending ability in the data analysis. A number of methodological challenges arise in method comparison research with respect to the application of Bland-Altman and trending analysis. Failure to face these methodological challenges will lead to misinterpretation and erroneous conclusions. We therefore review the basic principles and pitfalls of Bland-Altman analysis in method comparison studies concerning new CO monitors. In addition, the concept of clinical concordance is introduced to evaluate trending ability from a clinical perspective. The primary scope of this review is to provide a complete overview of the pitfalls in CO method comparison research, whereas other publications focused on a single aspect of the study design or data analysis. This leads to a stepwise approach and checklist for a complete data analysis and data representation.

Bearing in mind the previous Gauteng Education MEC’s recent indication that “discipline starts at home”,1 our article focuses on what South African law has contributed during the past 20 years to prompt parents participate accountably with partners in public school education, and how case law has defined parent accountability in this regard. Examples of relevant legislation would be those which assign the ultimate responsibility for learner conduct to parents, and call for a harmonious relationship between parents and educators. In line with the South African Schools Act’s requiring that parents partner with the State, educators and learners in accepting responsibility for their children’s schooling, this article highlights the need for a shared vision of the way forward. The importance of having such a shared vision to bring these disparate stakeholders’ aspirations together around the common goal, namely to develop all learners’ talents and capabilities, is underscored. The authors argue that factors such as reciprocal blame and a lack of cooperation are among the problems that hamper the full realisation in practice of the legislative provisions pertaining to parental accountability. Our article identifies solutions to this challenge, such as parents’ setting upright examples by behaving in an accountable manner, and recommendations, such as empowering parents for their roles as partners in education.Keywords: Education Law, parental responsibility, participation, accountability, learner discipline, partners in education

Social network analysis is a powerful tool that enables us to describe and quantify relationships between individuals. So far most of the studies rely on the analyses of various network snapshots, but do not capture changes over time. Here we use a stochastic actor-oriented model (SAOM) to test both the structure and the dynamics of relationships of three groups of wild vervet monkeys. We found that triadic closure (i.e. the friend of a friend is a friend) was significant in all three groups while degree popularity (i.e. the willingness to associate with individuals with high degree of connections) was significant in only two groups (AK, BD). The structure and dynamics of relationships according to the attributes of sex, matrilineand age differed significantly among groups. With respect to the structure, when analyzing the likelihood of bonds according to the different attributes, we found that individuals associate themselves preferably to individuals of the same sex only in two groups (AK, NH), while significant results for attachment to individuals of the same matriline were found also in two groups (BD, NH). With respect to the dynamics, i.e. how quickly relationships are modified, we found in two groups (AK, BD) that females’ relationships were more prone to variation than males’. In the BD group, relationships within high-ranking matrilines were less stable than low-ranking ones while in the NH group, juveniles’ relationships were also less stable than adults’ ones. The intergroup variation indicates that establishing species-specific or even population specific characteristics of social networks for later between-species comparisons will be challenging. Although, such variation could also indicate some methodological issue, we are quite confident that data was collected similarly within the different groups. Our study therefore provides a potential new method to quantify social complexity according to natural demographic variation.

Bearing in mind the previous Gauteng Education MEC's recent indication that "discipline starts at home",¹ our article focuses on what South African law has contributed during the past 20 years to prompt parents participate accountably with partners in public school education, and how case law has defined parent accountability in this regard. Examples of relevant legislation would be those which assign the ultimate responsibility for learner conduct to parents, and call for a harmonious relationship between parents and educators. In line with the South African Schools Act's requiring that parents partner with the State, educators and learners in accepting responsibility for their children's schooling, this article highlights the need for a shared vision of the way forward. The importance of having such a shared vision to bring these disparate stakeholders' aspirations together around the common goal, namely to develop all learners' talents and capabilities, is underscored. The authors argue that factors such as reciprocal blame and a lack of cooperation are among the problems that hamper the full realisation in practice of the legislative provisions pertaining to parental accountability. Our article identifies solutions to this challenge, such as parents' setting upright examples by behaving in an accountable manner, and recommendations, such as empowering parents for their roles as partners in education.

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