Ruffed lemurs (
Varecia
spp.) exhibit a unique suite of behavioral traits compared to other lemur species, which includes their fluid fission–fusion social dynamics, communal rearing of parked ...litters, and pronounced frugivory in their humid rainforest habitats. Given these traits, and the dense rainforests they inhabit, vocal communication may be key to maintaining social cohesion, coordinating infant care, and/or defending their high-quality food resources. Indeed, they are known for their raucous ‘roar-shriek’ calls. However, there has been surprisingly little research on vocal communication in
Varecia
species and only two previously published repertoires, both of which were qualitative descriptions of their calls. In this study, we quantitatively examined the vocal repertoire of wild black-and-white ruffed lemurs (
Varecia variegata
) at Mangevo, Ranomafana National Park, Madagascar. We characterized 11 call types using 33 bioacoustic parameters related to frequency, duration, tonality, and composition. We also used discriminant function analysis and hierarchical clustering to quantitatively and objectively classify call types within the black-and-white ruffed lemur vocal repertoire. The repertoire consists of both monosyllabic and multisyllabic calls that are individually given or emitted in contagious choruses. Eight of the 11 calls were also used in combination or in larger multi-call sequences. The discriminant function analysis correctly assigned call types with 87% success, though this varied greatly by call type (1–65%). Hierarchical clustering identified 3–4 robust clusters, indicating low clustering structure in the data and suggesting that
V. variegata
exhibits a graded vocal repertoire. Future work should consider the environmental and behavioral contexts in which calls are used to better understand the function of these call types and combinations.
Vocal communication is an important modality for group-living primates inhabiting dense forest habitats that can hinder visual and olfactory signals. Nevertheless, research on primate vocalizations ...has historically focused on a narrow subset of haplorhine taxa; comparatively few studies have been focused on strepsirrhines, despite facing similar ecological and social challenges. Ruffed lemurs (
Varecia
)—a taxon known for their raucous calls—are rainforest specialists that exhibit strong fission–fusion dynamics and communally rear large litters of young. However, surprisingly few studies have examined
Varecia
vocalizations in the wild
,
meaning virtually nothing is known about the call types or how they facilitate their unique social and reproductive strategies. Our goal for this study was to examine how various contextual factors such as weather, behavioral state, and subgroup size and composition affected vocal activity across call types in wild black-and-white ruffed lemurs
.
We conducted focal follows on 31 individuals (two communities) in Mangevo (Ranomafana National Park) from May–August 2019 to record behavioral and vocal activity. We distinguished 11 call types, although three (hum, roar-shriek, chatter) constituted the majority of vocal activity. Calling rates were consistent throughout the day, but decreased with high rainfall. We found sex- and subgroup-specific differences in call usage, likely related to female dominance and subgroup composition, respectively. We identified behavioral contexts that some call types were consistently given in; this can be used to help infer call function. This study provides some of the first quantitative analyses of ruffed lemur vocal communication and lays the groundwork for more systematic hypothesis testing in future studies.
Those promoting the corporate social responsibility agenda to small and medium-sized enterprises (SMEs) are interested in the potential of supply chain drivers as an incentive. This paper presents ...results from an empirical study into the attitudes and behaviours of 103 UK SME owner/managers in response to buyer pressure to demonstrate CSR activities. Most said that the inclusion of social and environmental requirements as preconditions to supply would increase their motivation to engage in CSR (82% for environmental criteria and 55% for social criteria). However, a quarter would be put off tendering and 12% thought that such criteria would be counter productive.
Mammals chew more rhythmically than lepidosaurs. The research presented here evaluated possible reasons for this difference in relation to differences between lepidosaurs and mammals in sensorimotor ...systems. Variance in the absolute and relative durations of the phases of the gape cycle was calculated from kinematic data from four species of primates and eight species of lepidosaurs. The primates exhibit less variance in the duration of the gape cycle than in the durations of the four phases making up the gape cycle. This suggests that increases in the durations of some gape cycle phases are accompanied by decreases in others. Similar effects are much less pronounced in the lepidosaurs. In addition, the primates show isometric changes in gape cycle phase durations, i.e. the relative durations of the phases of the gape cycle change little with increasing cycle time. In contrast, in the lepidosaurs variance in total gape cycle duration is associated with increases in the proportion of the cycle made up by the slow open phase. We hypothesize that in mammals the central nervous system includes a representation of the optimal chew cycle duration maintained using afferent feedback about the ongoing state of the chew cycle. The differences between lepidosaurs and primates do not lie in the nature of the sensory information collected and its feedback to the feeding system, but rather the processing of that information by the CNS and its use feed-forward for modulating jaw movements and gape cycle phase durations during chewing.
Allomaternal care is a rare, though phylogenetically widespread, mammalian infant care strategy. Among primates, the effects of allomaternal care are marked; its presence correlates with faster ...infant growth, younger age at weaning, and shorter interbirth intervals. Recent comparative research has found that such fertility benefits are absent in other mammals and are thus unique to primates. In large part because data describing lemur allomaternal care were lacking, the reproductive advantages of allomaternal care have never been demonstrated in Malagasy strepsirrhines. Using newly available data and rigorous phylogenetic methods, we extend this hypothesis to strepsirrhines and test whether allomaternal care in lemurs confers similar maternal reproductive benefits. Contrary to expectations, the presence of allomaternal care did not significantly impact lemur reproductive output; we did not find relationships between allomaternal care and either fetal or postnatal growth rates or interbirth intervals. Rather, infant parking and nesting, strategies employed primarily by litter-bearing species, were positively associated with faster fetal and postnatal infant growth, while nesting was negatively associated with interbirth interval. Thus, although each form of haplorrhine allomaternal care is also observed in Malagasy primates, the effects that these behaviors have on female reproductive output more closely resemble nonprimate mammals. We suggest that Malagasy strepsirrhines may not equally benefit from allomaternal care compared to haplorrhines because reproductive rates are less flexible and allomaternal care may instead increase infant survival in Madagascar's harsh and unpredictable environment. Our study has significant implications for understanding the evolution of infant care and developmental trajectories in mammals.
This article examines how pacing strategies during exercise are controlled by information processing between the brain and peripheral physiological systems. It is suggested that, although several ...different pacing strategies can be used by athletes for events of different distance or duration, the underlying principle of how these different overall pacing strategies are controlled is similar. Perhaps the most important factor allowing the establishment of a pacing strategy is knowledge of the endpoint of a particular event. The brain centre controlling pace incorporates knowledge of the endpoint into an algorithm, together with memory of prior events of similar distance or duration, and knowledge of external (environmental) and internal (metabolic) conditions to set a particular optimal pacing strategy for a particular exercise bout. It is proposed that an internal clock, which appears to use scalar rather than absolute time scales, is used by the brain to generate knowledge of the duration or distance still to be covered, so that power output and metabolic rate can be altered appropriately throughout an event of a particular duration or distance. Although the initial pace is set at the beginning of an event in a feedforward manner, no event or internal physiological state will be identical to what has occurred previously. Therefore, continuous adjustments to the power output in the context of the overall pacing strategy occur throughout the exercise bout using feedback information from internal and external receptors. These continuous adjustments in power output require a specific length of time for afferent information to be assessed by the brain's pace control algorithm, and for efferent neural commands to be generated, and we suggest that it is this time lag that crates the fluctuations in power output that occur during an exercise bout. These non-monotonic changes in power output during exercise, associated with information processing between the brain and peripheral physiological systems, are crucial to maintain the overall pacing strategy chosen by the brain algorithm of each athlete at the start of the exercise bout.
Providing care for someone with a disease or chronic condition can have a negative psychological, physical, social, and economic impact upon informal caregivers. Despite the socio-economic relevance ...and more than three decades of caregiver intervention research only very few translational efforts of successful interventions are reported. Still less of these interventions have been implemented into routine services. The aim of the ReDiCare study (German acronym BerTA) is to evaluate the effectiveness of a stepped counselling approach for burdened caregivers delivered by care counsellors of two long-term care insurances and registered psychotherapists.
A pragmatic randomised controlled trial with 572 caregivers of older adults (≥ 60 years) receiving benefits of one of the two participating long-term care insurances. Participants are assigned (t
) to either the ReDiCare intervention or a control group receiving routine care and counselling. Data are collected at baseline (-t
), 3-month (t
), 9-month (t
) and 15-month (t
). The 9-month post-intervention assessment (t
) is the primary endpoint to evaluate the results on the primary and secondary outcomes, measured by self-reported questionnaires. Depressive symptoms measured with the CES-D are the primary outcome. The main secondary outcomes are physical complaints, utilization of psychosocial resources, caregiver self-efficacy and burden, positive aspects of caregiving and perceived care quality. A process evaluation, including audio tapes, self-report questionnaires and documentation will be conducted to examine internal and external validity of the intervention. Data on direct and indirect costs are collected for the (health) economic evaluation, using a health care perspective and a societal perspective.
While comparable previous caregiver interventions have been developed and evaluated for specific caregiver groups (e.g. dementia caregivers, stroke caregivers), the ReDiCare study will indicate whether a stepped approach will be effective also in a broader group of caregivers. The intervention is one of the very few translational studies in caregiver intervention research and will provide valuable insights into relevant factors for training, intervention protocol adherence, effectiveness, and costs for future implementation steps.
Deutsches Register Klinischer Studien (German Clinical Trials Register), DRKS00014593 ( www.drks.de, registered 14 May 2018) and International Clinical Trials Registry Platform, DRKS00014593 ( https://apps.who.int/trialsearch/ ).
It is common practice to withhold IV thrombolysis (IVT) for acute ischemic stroke in patients with preexisting disabilities. To test the hypothesis of an association of IVT and good clinical outcome ...also in patients with preexisting disabilities without an increase in mortality, we analyzed data from 52,741 patients (15,317 treated with IVT) depending on prestroke Rankin Scale (pRS) score.
We performed an observational study based on a consecutive stroke registry covering 10.8 million inhabitants. The outcome at discharge of patients with stroke admitted in the time window of potential eligibility for IVT (<4.5 hours after stroke onset) was compared between patients treated and those not treated with thrombolysis, stratified by pRS score. Logistic regression analysis was used to estimate adjusted odds ratios (ORs) along with 95% confidence intervals (CIs) for favorable clinical outcome, defined as returning to the baseline pRS score or a score of 0 or 1 and mortality. Sensitivity analyses for subgroups of mildly and severely affected patients with stroke were performed, and the influence of treatment duration was assessed.
Among included patients, IVT rates were 32% for patients with pRS scores of 0 to 1 and 20% for patients with pRS scores of 2 to 5. IVT in patients with pRS scores of 0 to 4 was associated with a higher chance of returning to the baseline pRS score (or a modified Rankin Scale score of 0/1), with ORs ranging between 1.42 (pRS score 2; 95% CI 1.16-1.73) and 1.73 (pRS score 0; 95% CI 1.61-1). The OR observed in patients with a pRS score of 5 was 0.65 (95% CI 0.25-1.70). Observed associations remained consistent in sensitivity analyses. Subgroup analyses revealed no evidence of bias due to potential floor and ceiling effects. No evidence of elevated in-hospital mortality of patients treated with thrombolysis was observed.
Our study suggests that IVT can be effective even in patients with severe preexisting disabilities, provided that they were not bedridden before stroke onset. Withholding IVT on the sole ground of prestroke disabilities may not be justified.
Two-stage concrete (TSC) is a sustainable concrete which is produced by forcing a flowable cement grout mixture through the voids of a skeletal mass made of compacted preplaced aggregates. From the ...technical and economic aspects, TSC is particularly useful for construction and repair of concrete structures especially foundations, underwater construction, nuclear reactors, concrete dams, heritage structures and in constructions with closely spaced reinforcement. TSC differs from ordinary concrete in that it contains a higher proportion of stone aggregate and the aggregate stays in point-to-point contact as placed. Thus, the mechanical characteristics of the TSC in failure conditions are distinctly different from ordinary concrete. This paper presents the results of experimental investigations conducted to evaluate the compressive, tensile strength and modulus of elasticity of TSC using grouts with different water-to-cement ratios and admixture contents. It was found that the modulus of elasticity and splitting tensile strength of TSC are equivalent or higher than that of conventional concrete at the same compressive strength. In this method of construction, the splitting tensile strength can be conservatively estimated using the American concrete institute (ACI) equation for conventional concrete.
PDF
