Physiological Cost Research Articles

Physiological cost of antibiotic resistance: Insights from a ribosome variant in bacteria.

Antibiotic-resistant ribosome variants arise spontaneously in bacterial populations; however, their impact on the overall bacterial physiology remains unclear. We studied the naturally arising antibiotic-resistant L22* ribosome variant of Bacillus subtilis and identified a Mg2+-dependent physiological cost. Coculture competition experiments show that Mg2+ limitation hinders the growth of the L22* variant more than the wild type (WT), even under antibiotic pressure. This growth disadvantage of L22* cells is not due to lower ribosome abundance but rather due to reduced intracellular Mg2+ levels. Coarse-grained elastic-network modeling of ribosome conformational dynamics suggests that L22* ribosomes associate more tightly with Mg2+ when compared to WT. We combined the structural modeling and experimental measurements in a steady-state model to predict cellular adenosine 5'-triphosphate (ATP) levels, which also depend on Mg2+. Experiments confirmed a predicted ATP drop in L22* cells under Mg2+ limitation, while WT cells were less affected. Intracellular competition for a finite Mg2+ pool can thus suppress the establishment of an antibiotic-resistant ribosome variant.

To Compare the Effects of 4 Weeks Low Intensity Intermittent Training (LIIT) and Low Intensity Continuous Training (LICT) on Heart Rate Reserve, Heart Rate Recovery and Physiological Cost Index on College Going Girls

Background and Aim: Exercise strengthens heart muscle, improves blood flow, and lowers blood pressure. This translates to a healthier heart that pumps blood more effectively, recovers faster after exertion, uses oxygen better; reducing risk of heart disease. Exercise intensity is important aspect of enhancing health-related fitness. Aim of the study is to make appropriate prescription of the fitness, obesity, diseased person according to their needs and also see the impact of both type of training. Methods and Materials: Interventional study was conducted on girls of a physiotherapy college, Ahmedabad. Ethical approval was taken. 14 girls were randomly divided into 2 groups (LIIT and LICT), Protocol of 42 min was completed on treadmill for 4 weeks (5 days/week). Training was done at 50–70% maximal heart rate, 11-13 RPE with Talk test. In both group 5 min of warm-up and cool-down period was given. In LIIT, 4 sets with 4 minute of interval (32min), in LICT continuous walking/jogging (32 min) was done. Unpaired t test was applied between outcomes. Statistical analysis was done using SPSS. Result: 7 girls with mean age of (20.5714+1.718) years were included in intermittent training, 7 girls with mean age of (22=2.160) years were included in continuous training, there was significant difference between HRr but no significant difference between HRR and PCI of both the groups. Conclusion: Present study concluded that intermittent training is better than continuous training on heart rate reserve, heart rate recovery and physiological cost index on college going girls. Keywords: Low intensity intermittent training (LIIT), Low intensity continuous training (LICT), Heart rate reserve, Heart rate recovery, Physiological cost index, College going girls.

Does High Self-Control Accelerate Epigenetic Aging in Low-Income Adolescents?

PurposePersistent self-control in the context of upward mobility in low-income adolescents, especially those of color, may have physiological costs, such as greater risks of developing cardiometabolic diseases in young adulthood. One potential mechanism linking self-control to cardiometabolic health is epigenetic age acceleration (EAA). However, little is known regarding the association between high self-control and EAA, as well as what factors may play protective roles. Therefore, we evaluated (1) the association between self-control and EAA and if this association varies by race and ethnicity, and (2) whether neighborhood collective efficacy (NCE) and school connectedness moderate the association in low-income adolescents. MethodsThis study used data from the Future of Families and Child Wellbeing Study. Participants included 772 adolescents with a household income <300% of poverty level (mean age: 15.6 years). Self-control, NCE, and school connectedness were all self-reported. EAA was assessed in saliva and estimated using Horvath, Skin and Blood, and Pediatric-Buccal-Epigenetic clocks. Multiple linear regression and PROCESS analyses were employed. ResultsHigher self-control was positively associated with EAA estimated by the skin and blood clock in low-income adolescents of color. Further, the association of higher self-control with EAA was not significant among low-income adolescents of color with higher NCE. No significant association was found among low-income White adolescents. DiscussionThe results suggest that supportive resources like neighborhood collective efficacy could mitigate adverse associations of high self-control with health in low-income adolescents of color.

The foraging behavior of gerbils reveals the ecological significance of crude oil pollution.

Despite extensive ecotoxicological evidence on the adverse effects of oil pollution on rodents, little is known about how rodents make decisions in oil-polluted environments (i.e., outside of lab settings). We investigated the foraging behavior of Allenby gerbils, Gerbillus andersoni allenbyi (GA), that were presented with feeding trays in a semi-natural environment. The trays contained seeds mixed into one of three types of soils - clean soil, and two different soil samples collected from two well-documented terrestrial oil spill sites in Israel. The oil spill disasters occurred in 1975 and 2014 and the spill sites are located within a few hundred meters of each other, in the 'Avrona Nature Reserve in the Arava hyper-arid region in Israel. Gerbils of both sexes avoided foraging in 2014-polluted soil, but surprisingly, they foraged more in 1975-polluted soil. Our results indicate that for the GA, the 1975-polluted soil is an advantageous substrate to forage on, probably because its texture facilitates more efficient foraging, leading to greater energetic gain, and creating a trade-off between energetic gain and perceived foraging cost due to its pollution. We also proceeded to investigate some physiological consequences of chronic exposure to the 2014-polluted soil in the laboratory. Chronic oil exposure did not lead to mortality or weight loss, but female gerbils exhibited heightened cortisol. We conclude that terrestrial oil pollution may have significant sublethal impacts on animal behavior, even when there is no obvious short-term physiological cost to the exposure.

Dynamics of Respiratory Rate and Heart Rate Variability when Performing a Cognitive Task of Two Levels of Complexity

The study examined heart rate variability (HRV) and respiratory rate during a cognitive task (reading) at two difficulty levels. Time, frequency and nonlinear analysis of HRV was used. It has been shown that both some indicators of HRV (HR, SDNN, RMSSD, SD2, SD2/SD1) and respiratory rate change with increasing mental load, however, they do not separately demonstrate significant differences at all three stages of the study. Therefore, for the first time for cognitive studies, an integral indicator was used that links the parameters of the heart with respiration – the physiological cost of activity (PhysCost), which was previously used in work with athletes when they performed physical exercises to failure. Changes in the PhysCost showed that differences between a simple and a complex task are observed at all stages of the study. Thus, it has been established that the difference in the functional state of a person in the process of performing a continuous task of two levels of complexity is most reliably revealed when using an integrative indicator connecting the activity of the respiratory system and the circulatory system.

Behavioural thermoregulation prevents thermal stress in lizard sperm fertility

Global warming is threatening ectotherms, with strong repercussions on their population dynamics. Body temperature in ectotherm reptiles is crucial to perform all their biological functions, which are maximized within a narrow interval. When faced with new or adverse thermal conditions, reptiles will respond with distributional changes, behavioural adjustments to maintain their internal temperature, or by adapting to the new environment, otherwise, extinctions will occur. Higher temperatures may have negative repercussions, for example, shortening periods of activity, affecting embryo development during gestation or decreasing viability of sperm cells in males. Through behavioural thermoregulation, reptiles can compensate for environmental variations (Bogert effect). Furthermore, according to Janzen’s hypothesis, the physiological cost of responding to adverse thermal conditions will be low in species exposed to higher thermal overlap. Here, we analysed the effect of a change in the thermal regime on sperm cell viability in Sceloporus megalepidurus, a small viviparous lizard from central Mexico. We hypothesized that an active thermoregulator inhabiting temperate mountains is able to prevent the effects of thermal change on sperm cell viability. We found that the change in thermal regime did not modify sperm cell viability, nor does it affect the maturation of sperm cells in the epididymis. Our results support the Bogert effect and suggest that, despite the high temperatures and low thermal quality, S. megalepidurus can maintain its body temperature within an optimal range for sperm cell viability.

Oxidative state is associated with migration distance, but not traits linked to flight energetics

Flight can be highly energy demanding, but its efficiency depends largely on flight style, wing shape and wing loading, and a range of morphological and lifestyle adaptations that can modify the cost of sustained flight. Such behavioural and morphological adaptations can also influence the physiological costs associated with migration. For instance, during intense flight and catabolism of reserves, lipid damage induced by pro‐oxidants increases, and to keep oxidative physiological homeostasis under control, the antioxidant machinery can be upregulated. Studies on the oxidative physiology of endurance flight have produced contradictory results, making generalization difficult, especially because multispecies studies are missing. Therefore, to explore the oxidative cost of flight and migration, we used samples collected during the breeding season from 113 European bird species and explored the associations of measures of antioxidant capacity (total antioxidant status, uric acid and glutathione concentration) and oxidative damage of lipids (malondialdehyde) with variables reflecting flight energetics (year‐round or specifically during migration) using a phylogenetic framework. We found that none of the traits predicting year‐round flight energy expenditure (flight style, wing morphology and flight muscle morphology) explained any measures of oxidative state. Our results suggest that birds endure their everyday flight exercise without or with low oxidative cost. However, oxidative damage to lipids and one component of the endogenous antioxidant system (uric acid), measured after the end of spring migration on breeding adult birds, increased with migration distance. Our results suggest that migration could have oxidative consequences that might be carried over to subsequent life‐history stages (breeding).

Physiological costs of warning: Defensive hissing increases metabolic rate and evaporative water loss in a venomous snake

To minimize predation risk and the cost of confronting predators, prey have developed a range of defensive strategies and warning signals. Although advantageous, defensive warnings may also induce physiological and energy costs to the emitter. Ventilatory sounds (hissing) are the most distributed warning sound in vertebrates. Because they involve the respiratory apparatus, defensive hissing may substantially increase evaporative water loss. Herein, we examined the determinants of hissing as well as its physiological costs in a medium-sized venomous snake, the long-nosed viper (Vipera ammodytes). We first used a neutral arena and applied standardized stimulation to measure the occurrence and acoustic characteristics of warning hissing. Then, we used open-flow respirometry to quantify changes in respiratory gas exchanges (oxygen consumption and evaporative water loss) during defensive responses. We demonstrated that males are more likely to engage in sound warnings when stimulated. Expirations generated the strongest signals compared to inspiration but did not differ between sexes. We found that defensive hissing dramatically increased average metabolic rate and evaporative water loss during the 10-minute stimulation period, and this effect was more pronounced in males. Metabolic rates and evaporative water loss were closely related to the duration of hissing. Overall, our results indicate that respiratory-based warning sounds induce significant physiological costs and may alter water balance. The higher responsiveness in males than females likely reflects sexually selective pressure (higher mobility for mate acquisition) and enhanced risk exposure.

Costs of induced defenses dissipate by maturity for diploid and triploid oysters

Oyster reef restoration efforts and on-bottom aquaculture are frequently plagued with high predation rates. Oysters are phenotypically plastic, and rearing juvenile oysters, Crassostrea virginica, with predator cues causes them to grow stronger shells that increases survivorship in the field. However, induced defenses (e.g., shell hardening in oysters) are often associated with cost-benefit trade-offs, and the extent the increased shell strength persists into adulthood and alters the growth of somatic and reproductive tissues remains unknown. We raised diploid oysters (used in reef restoration) and triploid oysters (used in aquaculture) with and without predator cues for one month before placing individuals on an oyster farm to grow to market size. Oyster shell characteristics, soft tissue mass, and reproductive investment were measured periodically over one year of culture and compared across treatments. Both diploid and triploid oysters had significantly stronger and smaller shells than controls at the end of their nursery period. However, while diploid shells became 15 % stronger and 17 % smaller than controls, triploid shells became 28 % stronger and 23 % smaller. Additionally, triploid oysters exposed to predator cues returned to the size of controls faster and maintained their shell strength differences longer than diploids. Differences in soft tissue mass between treatments mirrored the patterns exhibited in shell size and weight with greater initial physiological costs and faster recovery for triploid individuals. There was no significant difference in somatic or reproductive tissue mass between induced and control oysters of the same ploidy after seven months in the field. Triploid oysters were 15–110 % larger than diploids depending on the characteristic measured at maturity. Additionally, there was a significant interaction between treatment and ploidy because induced triploids had marginally greater growth than their control counterparts while induced diploids had marginally less growth than controls. These findings demonstrate that physiological costs of oysters reacting to predators in early life stages are minimal by the time individuals reach maturity. Early exposure to predator cues is a promising tool for improving oyster survivorship in restoration and aquaculture operations, especially in regions with high predation pressure.

Reproduction results in parallel changes of oxidative stress and immunocompetence in a wild long-living mammal-edible dormouse Glis glis.

Oxidative stress (OS) and impaired immune function (IF) have been proposed as key physiological costs of reproduction. The relationship between OS and IF remains unresolved, particularly in long-living iteroparous species. We studied physiological markers of maintenance (OS, IF markers) in lactating, post-lactating and non-lactating females of edible dormice-a long-living rodent. We predicted the OS balance and IF to be compromised by lactation, especially in older females expected to face stronger trade-offs between life functions. We found that the age predictor (body size) correlated negatively with white blood cell level (WBC), positively with neutrophils to lymphocytes ratio and had no effect on OS markers. Oxidative damage markers (reactive oxygen metabolites (ROMs); but not antioxidant capacity) and body size-adjusted WBC were the lowest in lactating, higher in post-lactating and the highest in non-lactating females. Body size/age did not affect this correlation suggesting a similar age-independent allocation strategy during reproduction in this species. The path analysis testing the causal relationship between ROMs and WBC revealed that IF is more likely to affect OS than vice versa. Our study indicates the trade-off between crucial life functions during reproduction and suggests that immunosuppression reduces the risk of OS; therefore, mitigating oxidative costs of reproduction.

The Influence of Elite Race Walkers’ Year-Long Training on Changes in Total Energy and Energy Cost While Walking at Different Speeds

The aim of the study was to assess the influence of year-long training of race walkers on physiological cost and total energy center of mass (CoM). The assessment performed was based on indicating the differences between the resulting energy cost in a group of elite race walkers walking at technical, threshold, and racing speeds calculated by physiological and biomechanical methods before beginning and after finishing a year-long training cycle. The study involved 12 competitive race walkers who had achieved champion or international champion level. Their aerobic endurance was determined by means of a direct method, applying an incremental exercise test on the treadmill. The gait of the participants was recorded using the 3D Vicon analysis system. Changes in mechanical energy amounted to the value of the total external work of the muscles needed to accelerate and lift the center of mass during a normalized gait cycle. The highest influence on the total external work increase for increasing speeds of gait in both examinations was attributed to the changes in the kinetic energy resulting from the center of mass movement. A statistically significant decrease of the mean value of total external work for racing speed was observed in the second examination (p &lt; 0.001). An approx. 8% decrease (NS) of EE energy cost, standardized by body mass and distance covered, was found between the first and second examinations. The energy cost and total external work were significantly differentiated by the walkers’ gait speeds (p &lt; 0.05–0.001). The energy cost significantly differed from the total external work at p &lt; 0.001.

Hot males: thermal biology of males and females during coercive mating in water striders Gerris lacustris

Sexual conflict theory predicts that males that adopt coercive mating strategies impose costs to females during copulation. Nevertheless, conflicting mating strategies may also affect males, although such effects on males are often neglected in the literature. Here, we seek to understand whether male water striders (Gerris lacustris) experience higher body temperatures than females during coercive mating behavior. We we explored whether the water temperature affected male and female body temperature differently, considering that water contact by females might serve as a thermal regulator. We built generalized linear mixed models considering the male and female temperature as the dependent variables. Air temperature (as a proxy for solar radiation), water temperature, and sex were used as predictor variables. Our results suggest that males are warmer than females, and despite females coming into contact with water during skimming, this contact does not significantly contribute to lowering their body temperature or improving thermoregulation under the observed conditions. These findings provide novel insights into the thermal biology of water striders. Future studies should focus on addressing whether warmer temperatures confer some advantages to males, such as increased mobility and better ability to hold onto females or impose physiological constraints and fitness costs.

Advancements in breeding for high oil content in maize (Zea mays. L)

Maize is one of the world’s most important food crops, supplying&gt;5% deity energy. Due to its wider adaptability, high yield potential, maize is widely utilized as food and animals world worldwide. It enriched with caloric starch and the high energy in its oil. The kernel oil content in commercial high-oil maize hybrids averages ∼8%, far lower than that in developed high-oil maize lines (as high as 20%). The maize seed/kernel consisted of endosperm (82%) and the germ (embryo and scutellum) (12%). The germ region makes up 80–84% of kernel oil, with the aleurone and endosperm making up 12% and 5%, respectively. High-oil maize may serve as a valuable forage maize germplasm for breeding. Maize oil is also considered as high-quality oil for human health due to the high proportion of polyun-saturated fatty acids. Selection for high oil increases the proportion of germ and further content of germ oil. The problems that over-shadow the successful production of high-oil corn are low grain yield potential, physiological cost of oil synthesis, low seed vigor, low kernel weight, shorter seed longevity, and poor germination of high-oil corn lines. It is necessary to make efforts to generate nested populations or use marker-assisted recurrent selection (MARS) to accumulate the advantageous quantitative trait loci (QTLs) in the pa-rental lines. The oil content of maize inbreeds and hybrids could be further improved with the use of transgenes, genomics, and metabolic engineering technologies in new insight for the development of high oil maize breeding and strategies.

Parties and the power of capital intensive under open-list proportional representation system: The case of Indonesia

Since the Indonesian election adopted the Open-List Proportional Representation (OLPR) system in 2009 until the present, most political parties have altered their campaign strategies in the parliamentary election. The ownership of capital intensive is seemingly a certainty for political parties if they wish to succeed in the electoral match. Therefore, this article is aimed to demonstrate that capital intensive has a powerful impact in regard to the party triumph in the electoral arena under an OLPR system. It can be seen with the successful experience of four political parties in Indonesia, namely the Gerindra Party (Great Indonesia Movement), PKB (National Awakening Party), the Nasdem Party (National Democrat), and PKS (Prosperous Justice Party) in two elections, 2014 and 2019. Methodologically, it is qualitative research by utilizing in-depth interviews and online news gathering as the data collection technique. With the usage of four marketing-mix indicators (product, price, place, promotion), the article findings revealed that most political parties generally had uniformity in those four indicators despite different ideologies, programs, and strategies. Each party respectively required financial costs, an ideological platform, past achievements, popular candidate profile, physiological costs, local networks, direct campaign strategies to voters, elite approaches, and tactical promotions through mass media. Thus, this study concludes that these costs, which are referred to as “capital intensive,” determine the party’s victory in achieving electoral success.

Investigating the Effects of Exergame Training on Functional Activities Among Newly-Fitted Patients with Unilateral Transtibial Amputation: A Preliminary Study

Introduction: This preliminary study investigates the effects of adding exergame (EG) training to conventional exercises on the functional activities of newly fitted patients with unilateral transtibial amputation. Materials and Methods: A total of 22 newly fitted patients with unilateral transtibial amputation were equally and randomly divided into two groups as follows: the EG group who performed exercises and EG training and the control group who performed exercise only. The 2-min walk test, timed up and go test, amputee mobility predictor with prosthesis test, and physiological cost index were assessed at baseline and after 2 and 4 weeks of the intervention. Results: Both interventions effectively improved the 2-min walk test distance, timed up-and- go test, and the amputee mobility predictor with prosthesis test scores in patients with newly fitted transtibial amputation (P&lt;0.001). Additionally, a significant improvement was observed in the timed up-and-go test time in the EG group versus the control group after the 4-week intervention (P=0.04, effect size=0.53). Conclusion: The findings of this preliminary study further support that adding EG to exercises significantly increases movement speed among amputee patients.

Experimental evolution for improved postinfection survival selects for increased disease resistance in Drosophila melanogaster.

Disease resistance (defined as the host capacity to limit systemic infection intensity) and disease tolerance (defined as the host capacity to limit infection-induced damage) are 2 complementary defense strategies that help the hosts maximize their survival and fitness when infected with pathogens and parasites. In addition to the underlying physiological mechanisms, the existing theory postulates that these 2 strategies differ in terms of the conditions under which each strategy evolves in the host populations, their evolutionary dynamics, and the ecological and epidemiological consequences of their evolution. Here, we explored if one or both of these strategies evolve when host populations are subjected to selection for increased postinfection survival. We experimentally evolved Drosophila melanogaster populations, selecting for the flies that survived an infection with the entomopathogen Enterococcus faecalis. We found that the host populations evolved increased disease resistance in response to selection for increased survival. This was despite the physiological costs associated with increased resistance, the expression of which varied with the phase of infection. We did not find evidence of any change in disease tolerance in the evolved host populations.

Are companies ethically justified in offering nonmedical egg freezing as an employee benefit?

All over the world, many companies are including oocyte cryopreservation for nonmedical reasons, also popularly known as nonmedical egg freezing (NMEF), within their employee benefits packages. However, it is important to ask whether companies are ethically justified in offering NMEF as a benefit for their employees. The inclusion of NMEF within companies' employee benefits packages could be ethically justified in two ways. On the one hand, company-sponsored NMEF can serve as a strategy to mitigate or eliminate gender inequalities in the workplace, such as female underrepresentation in positions of authority and leadership and the so-called work/motherhood conflict. On the other hand, company-sponsored NMEF can be a means to expand women's reproductive autonomy by making egg freezing accessible to those women who are not able to afford it otherwise. This article calls into question these ethical justifications. We argue that by offering NMEF as an employee benefit, companies maintain current workplace inequalities and impose an option for women with multiple risks and externalities. Therefore, companies' offering of NMEF benefits cannot be ethically justified. Furthermore, we argue that companies that offer NMEF benefits incur fiduciary responsibilities related to the physiological, emotional, psychological, and financial costs of the use of company-sponsored NMEF.

Wounded but unstressed: Moose tolerate injurious flies in the boreal forest.

Moose (Alces alces) in boreal habitats feed and rest where they are exposed to Dipteran flies and the parasites they carry. We collected 31,905 flies during the summer from 12 habituated moose on the Kenai Peninsula, Alaska. Moose flies, Haematobosca alcis (Snow), Diptera: Muscidae-a species that completes its entire life cycle on or around moose-accounted for 91% of flies collected; the reminder of the flies collected included mosquitoes (Culicidae), black flies (Simuliidae), and deer flies (Tabanidae). Flies impose physiological costs for moose, e.g., vectors for parasites such as Legworm (Onchocerca spp.) which causes sores on the hind legs of moose. We found that the number of sores present on the hind legs of moose is positively correlated with body fat, which suggests a correlation between gains of energy and damage from flies. We also found that the number of sores is negatively correlated with serum albumin, which is indicative of an inflammatory response and body protein being used to repair injuries from flies and parasites. The number or type of flies present on a Moose were not correlated with the concentration of corticosteroids in saliva or feces. Flies do not elicit a stress response in moose even though the costs of repairing wounds and resisting infections of those wounds likely reduce gains of protein from summer foraging. Moose can tolerate the injuries from biting flies with regular gains from summer foraging but exposure to insect-borne parasites poses a risk to reproduction and survival.

A usability study on the inGAIT-VSO: effects of a variable-stiffness ankle-foot orthosis on the walking performance of children with cerebral palsy

BackgroundAnkle-foot orthoses (AFOs) are commonly used by children with cerebral palsy (CP), but traditional solutions are unable to address the heterogeneity and evolving needs amongst children with CP. One key limitation lies in the inability of current passive devices to customize the torque–angle relationship, which is essential to adapt the support to the specific individual needs. Powered alternatives can provide customized behavior, but often face challenges with reliability, weight, and cost. Overall, clinicians find certain barriers that hinder their prescription. In recent work, the Variable Stiffness Orthosis (VSO) was developed, enabling stiffness customization without the need for motors or sophisticated control.MethodsThis work evaluates a pediatric version of the VSO (inGAIT-VSO) by investigating its impact on the walking performance of children with CP and its potential to be used as a tool for assessing the effect of variable stiffness on pathological gait. Data was collected for three typical developing (TD) children and six pediatric participants with CP over two sessions involving walking/balance tasks and questionnaires.ResultsThe sensors of the inGAIT-VSO provided useful information to assess the impact of the device. Increasing the stiffness of the inGAIT-VSO significantly reduced participants’ dorsiflexion and plantarflexion. Despite reduced range of motion, the peak restoring torque increased with stiffness. Overall the participants’ gait pattern was altered by reducing crouch gait, preventing drop-foot and supporting body weight. Participants with CP exhibited significantly lower (p < 0.05) physiological cost when walking with the inGAIT-VSO compared to normal condition (own AFO or shoes only). Generally, the device did not impair walking and balance of the participants compared to normal conditions. According to the questionnaire results, the inGAIT-VSO was easy to use and participants reported positive experiences.ConclusionThe inGAIT-VSO stiffnesses significantly affected participants’ plantarflexion and dorsiflexion and yielded objective data regarding walking performance in pathological gait (e.g. ankle angle, exerted torque and restored assistive energy). These effects were captured by the sensors integrated in the device without using external equipment. The inGAIT-VSO shows promise for customizing AFO stiffness and aiding clinicians in selecting a personalized stiffness based on objective metrics.

More allogrooming is followed by higher physiological stress in wild female baboons.

Social bonds increase fitness in a range of mammals. One pathway by which social bonds may increase fitness is by reducing the exposure to physiological stress, i.e. glucocorticoid (GC) hormones, that can be detrimental to health and survival. This is achieved through downregulating hypothalamic-pituitary-adrenal (HPA)-axis activity. Indeed, long-term measures of social (grooming) bonds are often negatively correlated with HPA-axis activity. However, the proximate role of physical touch through allogrooming remains an open question in the sociality-health-fitness debate. Demonstrating the potential anxiolytic benefits of grooming in the wild is hindered by methodological limitations. Here, we match accelerometer-identified grooming in wild female chacma baboons (Papio ursinus) to non-invasive faecal GC metabolite concentrations (fGCs). Consistent with previous work, we found a negative (but statistically non-significant) overall relationship between individual averaged fGCs and grooming rates. However, when time-matching grooming to fGCs, we found that both more giving and receiving grooming were followed by higher fGCs. This upregulation of HPA-axis activity suggests that maintaining social bonds (and its ultimate fitness benefits) may come at a shorter-term physiological cost. This finding sheds new light on a ubiquitous social behaviour typically considered 'relaxing' and suggests that sociopositive contact can trigger physiological stress.