250 research outputs found
Socio-ecological determinants of movement behaviour in red-tailed monkeys (Cercopithecus ascanius schmidti)
In group-living primates, costs and benefits of sociality are reflected in movement behaviour: where groups move in their environment, and how individuals maintain cohesive groups while moving. Establishing environmental and social determinants of movement behaviour reveals adaptive responses that characterise primate sociality. For primates in different habitats, intra-specific behavioural variation provides insight into ecological pressures that drive habitat-specific adaptive responses. I investigated how group ranging and two individual behaviours that mediate intra-group cohesion – spatial positioning and contact calling – relate to food availability, weather, and social contexts in red-tailed monkeys (Cercopithecus ascanius), a forest guenon that also lives in forest scarce savanna-woodland environments. I predicted food availability and weather would have stronger effects on ranging in more seasonal savanna mosaics than forests, and individuals would 1) adjust inter-individual distances in response to increased feeding competition, and 2) adjust contact call acoustic structure to maximise propagation when neighbours were further away. I collected behavioural and ecological data at Ngogo, Uganda, a predominantly forested habitat with small patches of secondary forest, and Issa, Tanzania, a woodland-dominated mosaic with thin strips of riparian forest. Larger home ranges sizes and longer travel distances at Issa reflected lower food availability and hotter temperatures than at Ngogo. Behavioural responses to thermal conditions in secondary forest and woodland suggested comparable environmental heterogeneity across sites at fine spatial scales. Ngogo monkeys increased inter-individual distances where food availability was low and when travelling slower. Individual cohesion indicates trade-offs between reducing feeding competition and social foraging. Ngogo monkeys also adjusted call structures to match expected propagation to conspecifics depending if neighbours produced preceding grunts (i.e. antiphony). Environmental and social drivers of intra-specific movement behaviour reveal adaptive behavioural responses through which primates maintain sociality. Habitat-specific behaviour in red-tailed monkeys also improves our understanding of adaptations in hominins distributed across similar vegetation gradients
Central Hemodynamics Measured During 5 Repetition Maximum Free Weight Resistance Exercise
International Journal of Exercise Science 11(2): 342-354, 2018. The PhysioFlowâ„¢ is a piece of equipment that uses bioimpedance cardiography to measure central hemodynamics. The purpose of this research was to explore the novel approach of monitoring central hemodynamics during free weight resistance exercise using bioimpedance cardiography throughout a 5 repetition maximum (5RM). Thirty participants ranging from beginner to advanced lifters (16 males and 14 females) completed a 5RM for back squat, seated push press, and bicep curl while connected to the PhysioFlowâ„¢ to assess the response of heart rate (HR), stroke volume (SV), cardiac output (Q), and ejection fraction (EF). Participants were cued for form and to breathe normally throughout the lifts. The PhysioFlowâ„¢ detected an increase in HR and Q for all lifts between rest and each repetition (p \u3c 0.05). There was also an increase in HR and Q from repetition 1 to repetition 5 for all lifts (p \u3c 0.05). No changes in EF or SV were detected between resting measurements and each repetition for all lifts (p \u3e 0.05) and no changes in EF or SV were detected when all repetitions were compared to each other for all lifts (p \u3e 0.05). In conclusion, the PhysioFlowâ„¢ was able to detect changes in HR and Q during dynamic free weight resistance exercise. This novel approach may provide a mechanism for monitoring central hemodynamics during free weight resistance training. However, more research needs to be conducted as the exercise protocol for this investigation did not allow for a comparison to a reference method
Evaluation of Fat-free Mass Characteristics at Different Adiposity Levels: Impact of Weight Status Stratification Method
The method used to stratify weight status when evaluating fat-free mass (FFM) characteristics has primarily been based upon body mass index (BMI) and not body fat percent (BF%). As a result, it is unknown whether deviations in FFM characteristics are similar when stratifying weight status based upon BMI or BF%. Purpose: The purpose of this study was to evaluate FFM characteristics at different adiposity levels when stratifying weight status via BMI and BF%. Methods: 150 adults (50% males) participated in this study. 3-compartment (3C) model body composition was based upon body density (Db) via air displacement plethysmography (ADP) and total body water via bioimpedance analysis. FFM density (DFFM), residual (RFFM), and hydration (HFFM)were evaluated in all subjects. The Db obtained from a stand-alone assessment of ADP (2C-Db) and 3C model (3C-Db)were also compared between groups. Subjects were stratified based upon weight status (BMI and BF%). First, subjects were divided into a normal weight (NW-BMI), overweight (OW-BMI) or obese (OB-BMI) group, which were based upon BMI values of 18.5-24.99 kg/m2 (n=50), 25.0-29.99 kg/m2 (n=50), and ³ 30.0 kg/m2 (n=50), respectively. Next, subjects were divided into groups based upon BF% where normal weight BF% values (NW-BF%) for males and females were \u3c 25 and 35% (n=81), respectively, and obese BF% values (OB-BF%) were ³25 and 35% (n=69), respectively. Results: The DFFM ranged from 1.096 – 1.097 g/cm3 for all groups in both weight status stratification methods (all p \u3e 0.05). HFFM and RFFM were similar for all comparisons and ranged from 73.99 – 74.33% and 25.67 – 26.01%, respectively, for BMI groups and 74.02 – 74.26% and 25.74 – 25.98%, respectively, for BF% groups (all p \u3e 0.05). In contrast, the 3C-Db (1.050, 1.036, and 1.013 g/cm3) and 2C-Db (1.051, 1.036, and 1.014 g/cm3) were statistically significant for all comparisons between NW-BMI, OW-BMI, and OB-BMI respectively (all p \u3c 0.05). Furthermore, 3C-Db (1.051 and 1.011 g/cm3) and 2C-Db (1.052 and 1.012 g/cm3) were significantly different when comparing NW-BF% and OB-BF% (both p \u3c 0.05). CONCLUSIONS: Previous research has reported the FFM characteristics when stratifying weight status via BMI classification. As a result, it was unknown whether deviations in FFM characteristics existed when stratifying by BF%. Uniquely, the current study findings revealed that FFM characteristics are similar between groups regardless of the weight status stratification method (BMI or BF%)
An Experiential Learning Model: Collaborative Student Creations of Multidisciplinary Community Classroom Experience
A community classroom experience, grounded in the philosophy of experiential learning, was the gauntlet we threw down for our Education students and ourselves as instructors. We situated this experience in the pillars of community classroom and experiential learning. Goals for our students became twofold: goals as a current post-secondary student and goals as a future educator. To activate this experience, groups of students engaged both collaboratively and individually with exploratory learning at a local community classroom site. Student reflections showed deep value and learning through this experience and of this experience. There were challenges including navigating collaborative group work and the necessity of becoming vulnerable alongside the successes of connecting exploratory learning to the real world and witnessing authentic interdisciplinary work. Further questions arising from this research centre on authentic assessment practices and the idea of giving back to the community through these real world experiences
Teaching Lower Laryngeal Position with EMG Biofeedback
The authors explore new and innovative ways to teach singers how to maintain the lower laryngeal position while singing - a component of classical singing technique that many consider essential to achieving a vibrant, focused, and resonant tone
The Influence of Citrus urantium and Caffeine Complex versus Placebo on the Cardiac Autonomic Response: A Double Blind Crossover Design
Background: The purpose of this study was to examine the resting cardiac autonomic nervous system’s response to the ingestion of a complex containing Citrus aurantium + Caffeine (CA + C) and its influence on recovery following a high-intensity anaerobic exercise bout in habitual caffeine users. Methods: Ten physically active males (25.1 ± 3.9 years; weight 78.71 ± 9.53 kg; height 177.2 ± 4.6 cm; body fat 15.5 ± 3.13%) participated in this study, which consisted of two exhaustive exercise protocols in a randomized crossover design. On each visit the participants consumed either a CA + C (100 mg of CA and 100 mg of C) or placebo (dextrose) capsule. After consumption, participants were monitored throughout a 45-min ingestion period, then completed a repeated Wingate protocol, and were then monitored throughout a 45-min recovery period. Cardiac autonomic function (Heart Rate (HR) and Heart Rate Variability (HRV)) and plasma epinephrine (E) and norepinephrine(NE) were taken at four different time points; Ingestion period: baseline (I1), post-ingestion period (I2); Recovery period: immediately post-exercise (R1), post-recovery period (R2). Heart rate variability was assessed in 5-min increments. Results: A repeated measures ANOVA revealed significant time-dependent increases in HR, sympathetic relatedmarkers of HRV, and plasma E and NE at I2 only in the CA + C trial (p\u3c 0.05); however, no meaningful changes in parasympathetic markers of HRV were observed. Participants recovered in a similar time-dependent manner in all markers of HRV and catecholamines following the PLA and CA + C trials. Conclusion: The consumption of CA + C results in an increase of sympathetic activity during resting conditions without influencing parasympathetic activity. CA + C provides no influence over cardiac autonomic recovery
A Comparison of Anaerobic Power Tests using Cycle Ergometry and Non-motorized Treadmill Ergometry at Optimized Loads
International Journal of Exercise Science 16(4): 1293-1305, 2023. The purpose of this study was to compare performance markers derived from a 30-second maximal bout on a cycle ergometer (CE) and non-motorized treadmill (NMT) under optimized loads. Recreationally active participants (n = 40) volunteered for the study. Force-velocity tests on the CE and NMT were used to determine optimal resistance for peak power (PP) production. The remaining visits were randomized and counterbalanced, with a single 30-second maximal test on CE or NMT to assess PP, mean power (MP), fatigue index (FI), over the course of the 30-second test, and maximum heart rate (HRmax) and blood lactate (BLa-) taken 1-minute post. Results were that PP and MP were higher (P\u3c0.05) on CE compared to NMT for both sexes. FI did not differ among males (P=0.201) whereas females showed higher FI (P=0.002) on the CE. HRmax and BLa- were higher (P\u3c0.05) after NMT for both sexes. There was no difference for optimal braking force on NMT between males (16.65±4.49%BW) and females (14.30±3.10%BW) (P=0.061). CE optimal torque factor was higher for males (0.78±0.16 Nm/kg) compared to females (0.62±0.14 Nm/kg) (P=0.001). Overall, CE produced higher power output using optimized loads in recreationally active males and females, while NMT test resulted in a higher HRmax andBLa- concentration. These tests for anaerobic power, when performed with optimized loads, produced different results for several variables, therefore these modalities should not be considered interchangeable. Practitioners should consider which modality best mimics the activities of the person being tested when selecting a protocol
Observation of an Encounter between African Wild Dogs (Lycaon pictus) and a Chimpanzee (Pan troglodytes schweinfurthii) in the Issa Valley, Tanzania
There has been considerable discussion of chimpanzees (Pan troglodytes) as predators, most commonly of red colobus monkeys (Procolobus spp.). Far more infrequent are published descriptions of chimpanzees as prey. The paucity of direct observations of chimpanzee-predator encounters is an obstacle in situating chimpanzees in both predator and prey roles. For the first time, we describe an observation of an encounter between African wild dogs (Lycaon pictus) and a chimpanzee in the Issa Valley, Tanzania, one of the driest and most open chimpanzee habitats. Whilst the initiation of the encounter was missed, here we nonetheless interpret the data that we did record. Our observations of behavior in both parties suggest the possibility of an investigatory rather than predatory encounter on the part of the wild dogs
Cercopithecine and Colobine Abundance Across Protected and Unprotected Land in the Greater Mahale Ecosystem, Western Tanzania
Most primates live in unprotected land where abundances and threats may differ from those in protected areas. We therefore need to establish population densities in both unprotected and protected areas to effectively inform conservation planning. The Greater Mahale Ecosystem in western Tanzania is a region of mixed protected status with seven cercopithecine and colobine species: blue (Cercopithecus mitis doggetti), red-tailed (C. ascanius schmidi), and vervet (Chlorocebus pygerythrus) monkeys; ashy red colobus (Piliocolobus tephrosceles); black-and-white colobus (Colobus angolensis); and olive (Papio anubis) and yellow (P. cynocephalus) baboons. These species may be threatened by increasing human activity; however, except for ashy red colobus, no data on local abundances are available. We walked over 350 km of line transects in legally protected (Village Forest Reserves) and unprotected general land between August 2011 and October 2012 to estimate densities of primates and human activity. Primate densities were consistently low across the Greater Mahale Ecosystem. Blue and red-tailed monkey and ashy red colobus densities were especially low compared to populations in predominantly forested landscapes. Primate and human activity densities did not differ significantly inside and outside of reserves. Low primate densities could be natural responses to the lower proportions and quality of riparian forest habitat in the region. High levels of human activity and the absence of significantly higher primate densities in reserves suggest unprotected land could provide important refuges for primates in the Greater Mahale Ecosystem. This result further reinforces a broad need to include unprotected areas in primate conservation strategies. © 2019, The Author(s)
- …