Bout Duration Research Articles

First Account of the Breeding Biology of Indian Blue Robin (Larvivora brunnea) in Southwest China.

Breeding biology lies at the core of life history research on birds, and it provides important information for avian conservation. We discovered one nest of the Indian Blue Robin (Larvivora brunnea) on 28 May 2021, at the Laojun mountains in Lijiang, northwestern Yunnan, China. Field observation was combined with the use of a GoPro camera for video shooting to quantitatively study the incubation and brooding behavior. We also conducted measurements of the eggs and nestlings on site and inspected the nesting materials used. A bowl-shaped nest with four eggs was located at 2830 m in the evergreen deciduous broad-leaved forest. All eggs were successfully incubated and two nestlings fledged on 22 June 2021, resulting in a total breeding success of 50%. Only the female bird incubated the eggs and brooded the nestlings. The incubation period was at least 13 days and the nestling period was 13 days. As incubation progressed, the incubation bout duration decreased. During the incubation period, the nesting time of the female bird shows a declining trend as incubation progresses. Both parents participated in feeding the nestling, and the frequency of parental supply increased with the maturity of the nestling.

Temporal dynamics of awakenings from slow-wave sleep in non-rapid eye movement parasomnia.

Non-rapid eye movement parasomnia disorders, also called disorders of arousal, are characterized by abnormal nocturnal behaviours, such as confusional arousals or sleep walking. Their pathophysiology is not yet fully understood, and objective diagnostic criteria are lacking. It is known, however, that behavioural episodes occur mostly in the beginning of the night, after an increase in slow-wave activity during slow-wave sleep. A better understanding of the prospect of such episodes may lead to new insights in the underlying mechanisms and eventually facilitate objective diagnosis. We investigated temporal dynamics of transitions from slow-wave sleep of 52 patients and 79 controls. Within the patient group, behavioural and non-behavioural N3 awakenings were distinguished. Patients showed a higher probability to wake up after an N3 bout ended than controls, and this probability increased with N3 bout duration. Bouts longer than 15 min resulted in an awakening in 73% and 34% of the time in patients and controls, respectively. Behavioural episodes reduced over sleep cycles due to a reduction in N3 sleep and a reducing ratio between behavioural and non-behavioural awakenings. In the first two cycles, N3 bouts prior to non-behavioural awakenings were significantly shorter than N3 bouts advancing behavioural awakenings in patients, and N3 awakenings in controls. Our findings provide insights in the timing and prospect of both behavioural and non-behavioural awakenings from N3, which may result in prediction and potentially prevention of behavioural episodes. This work, moreover, leads to a more complete characterization of a prototypical hypnogram of parasomnias, which could facilitate diagnosis.

Maximal daily stepping cadence partially explains functional capacity of individuals with end-stage knee osteoarthritis.

Individuals with end-stage knee osteoarthritis (OA) walk at a lower intensity (ie, slower step cadence) contributing to worse physical function. Previous literature reports daily step counts and sedentary time, with little information regarding stepping bouts or cadence. Determining relationships between daily higher stepping cadence duration and clinical outcomes can move the field toward optimal daily stepping prescription. To quantify daily physical activity patterns of individuals with end-stage knee OA and determine the contribution of high stepping cadence to explain functional capacity variability. Cross-sectional analysis. Veterans Administration medical center. U.S. military veterans (n = 104; age: 67.1 years [7.2]; mean [SD]; male [89.3%]) with end-stage knee OA were enrolled. Not applicable. Functional capacity (6-Minute Walk Test [6MWT]). Physical activity (activPAL wearable sensor; cadence and time sitting, standing, and stepping), pain (Western Ontario and McMaster Universities Osteoarthritis Index-pain subscale) sociodemographic variables, and comorbidities (body mass index and Functional Comorbidity Index) are the main explanatory variables. Participants' wake time was mainly sitting (11.0 h/day) in ≥60-minute bouts (29.7% ± 12.7 of sitting time). Standing (3.4 hours/day) and stepping (1.4 h/day) primarily occurred in 0-5 minute bouts (standing: 87.7% ± 14.4 of standing time, stepping: 98.7% ± 12.7 of stepping time) and stepping cadence was predominantly incidental (1-19 spm; 52.9% ± 9.6 of total stepping time). Backward elimination model results indicated shorter medium-to-brisk cadence bout duration, older age, and higher pain significantly explained shorter 6MWT distance (AdjR2=0.24, p < .01). Individuals with knee OA spend most of their waking hours sitting, while standing and stepping occurs in short bouts at very low stepping cadence. Decreased time in high stepping cadence is associated with lower functional capacity. Future studies should explore if increasing the daily time spent in higher step cadence can improve functional capacity in this population.

Association between Physical Activity and Reduced Mortality in Inoperable Lung Cancer

We examined device-measured physical activity (PA) and sedentary behaviour at the time of diagnosis in people with inoperable lung cancer and investigated their associations with 12-month mortality. The people with inoperable lung cancer wore an accelerometer for seven days prior to the treatment commencement. The analysed PA/sedentary behaviour variables included light-intensity PA, moderate-to-vigorous-intensity PA (MVPA), step count, the total time spent sedentary, and the usual sedentary bout duration. The data on the disease stage, clinical covariates and 12-month mortality were extracted from medical records. Cox regression models were used to estimate the association between the PA measures and 12-month mortality, and the sedentary behaviour measures and 12-month mortality. The models were adjusted for the stage and neutrophil-to-lymphocyte ratio. All the PA and sedentary behaviour variables were dichotomised at their medians for analysis. Eighty-nine participants (70 ± 10 years; 55 [62%] males) contributed valid data. The twelve-month mortality was 30% (n = 27). Compared to the participants who spent ≤4.6 min/day in MVPA (n = 45), those who spent &gt;4.6 min/day (n = 44) had a relative risk of 12-month mortality reduced by 60% (hazard ratio, 0.40; 95% CI, 0.16 to 0.96; 18 versus nine deaths, respectively). The other variables of PA/sedentary behaviour were not associated with 12-month mortality. Higher device-measured MVPA was associated with reduced 12-month mortality in people who were newly diagnosed with inoperable lung cancer.

Sow nest-building behavior in communal farrowing relates to productivity and litter size

Sows have an innate need for prepartal nest-building (NB), which promotes parturition and nursing. However, the interpretation of NB in relation to different environments or sow physiology is unclear. We aimed to observe sow NB and reproductive performance in communal farrowing with 7.9–11.9 m2 total space per sow, individual unconfined farrowing pens and abundant straw. We observed 33 farrowings (Norwegian Landrace and Finnish Landrace x Yorkshire, mean parity 3.6 ± 1.8) with continuous video recording for NB during the last 24 h pre-partum, and followed the subsequent parturition and reproductive performance. Serum samples taken at the start of farrowing were analyzed for progesterone and prolactin, and a colostrum sample was analyzed for Ig-composition. Piglet weight at birth, 24 h later and at 3 weeks of age provided data for colostrum intake and piglet average daily weight gain (ADG). Average NB activity increased from 24 to 12 h to 12–0 h before farrowing (P < 0.001) but NB bout duration remained similar between the two different time phases. The peak of NB activity occurred 8–4 h before farrowing, but in sows with ≥17 piglets, compared to sows with ≤16 piglets, the activity peak was delayed (4–2 h vs. 8–6 h before farrowing), and NB activity 4–2 h and 2–0 h before farrowing was higher (P = 0.02, and P = 0.022, respectively). The average NB bout duration during 12–0 h before farrowing was positively related to serum prolactin concentration (P = 0.012) and negatively correlated with piglet ADG at 3 weeks (P = 0.024). Furthermore, during the same time phase, the frequency of NB bouts was positively correlated with colostrum BRIX and IgG-levels (P < 0.001 and P = 0.029, respectively) and negatively correlated with piglet mortality at lactation days 2–3 (P = 0.037). Earlier start of NB was negatively correlated with colostrum IgA levels (P < 0.001). Sows with higher progesterone levels at the start of farrowing had a higher piglet stillbirth incidence (P = 0.02). Current results from the novel communal farrowing environment suggest that higher intensity of NB 12–0 h before farrowing is related to an improved sow hormonal balance and colostrum quality, in addition to decreased piglet mortality. However, higher litter size delays the peak of nest-building activity, while it remains unclear whether this reflects a negative physiological response or a beneficial compensatory effect. Further research should aim at defining different elements of NB in different environments and reproductive outcomes.

Effects of supplementing colostrum beyond the first day of life on growth and health parameters of preweaning Holstein heifers

The preweaning period for a dairy calf is characterized by high morbidity and mortality rates, leading to financial losses for producers. Identifying strategies to improve the health and welfare of calves while reducing antimicrobial use continues to be crucial to the success of the dairy industry. The objective of this study was to determine the effects of feeding colostrum replacer (CR) to dairy heifer calves beyond d 1 of life on growth, serum IgG, the incidence of diarrhea and bovine respiratory disease (BRD), and the risk of mortality in the preweaning period. At birth, Holstein heifer calves (n = 200; 50/treatment) weighing 40.7 ± 0.35 kg (mean ± SE) were fed 3.2 L of CR (205 g IgG/feeding) at 0 h and 12 h of life. Calves were then randomly assigned to 1 of 4 treatments: 450 g of milk replacer (MR) from d 2 to 14 (control, CON), 380 g of CR + 225 g of MR from d 2 to 3, then 450 g of MR from d 4 to 14 (transition, TRAN), 45 g of CR + 450 g of MR from d 2 to 14 (extended, EXT); or 380 g of CR + 225 g of MR from d 2 to 3, then 45 g of CR + 450 g of MR from d 4 to 14 (transition + extended, TRAN+EXT). Each treatment was reconstituted to 3 L and fed twice daily. All CR treatments were fed using bovine-derived CR containing 27% IgG. From d 15 to 41, all calves were fed 600 g of MR reconstituted to 4 L twice daily. Body weight was recorded at birth and every 7 d until study completion on d 49. Blood samples were taken daily until d 7 to evaluate serum IgG and then every 7 d until d 49. A health assessment was performed daily to evaluate calves for BRD and diarrhea. Data were analyzed using mixed linear regression, mixed logistic regression, and survival analysis models in SAS 9.4. Serum IgG concentrations were not affected by treatment for the study period. The EXT and TRAN+EXT groups had greater average daily gain (ADG) from d 7 to 14 (0.14 kg/d) and the TRAN group had greater ADG from d 14 to 21 (0.11 kg/d), compared with CON. There was no association of treatment with the odds or the duration of a diarrhea bout. However, provision of CR to the TRAN and EXT calves was associated with a reduced hazard of diarrhea compared with CON calves. Furthermore, TRAN and EXT calves have a lower hazard of mortality compared with CON calves, with TRAN and EXT calves had a 2.8- and 3.8-times lower hazard of mortality, respectively. Our findings suggest that the supplementation of CR to dairy calves positively affects ADG, and reduces the hazard of diarrhea and mortality during the preweaning period. Future research should look to further refine the supplementation strategy of CR to calves and explore the mechanism of action.

Accelerometer-Measured Sedentary Behavior Patterns, Brain Structure, and Cognitive Function in Dementia-Free Older Adults: A Population-Based Study.

Sedentary behavior is associated with cognitive impairment, but the neuropathological mechanisms underlying their associations are poorly understood. To investigate the associations of accelerometer-measured sedentary behavior patterns with brain structure and cognition, and further to explore the potential mechanisms. This community-based study included 2,019 older adults (age≥60 years, 59% women) without dementia derived from participants in the baseline examination of MIND-China (2018-2020). We assessed sedentary parameters using an accelerometer and cognitive function using a neuropsychological test battery. Structural brain markers were assessed on the structural brain MRI scans in a subsample (n = 1,009). Data were analyzed using the general linear, isotemporal substitution, and mediation models. In the total sample (n = 2,019), adjusting for multiple covariates and moderate-to-vigorous-intensity physical activity, longer mean sedentary bout duration was linearly related with lower z-scores of global cognition, verbal fluency, and memory (ptrend < 0.05), whereas greater total sedentary time was linearly associated with lower z-scores of global cognition, verbal fluency, and memory only among individuals with long sedentary time (>10 h/day) (ptrend < 0.05); Breaking up sedentary time with same amount of light-intensity physical activity was significantly associated with higher verbal fluency and memory z-scores (p < 0.05). In the MRI subsample (n = 1,009), separately entering structural brain MRI markers into the mediation models substantially attenuated the associations of mean sedentary bout duration with global cognition, verbal fluency, and memory z-scores. Prolonged uninterrupted sedentary time is associated with poor global cognition, memory, and verbal fluency among rural older adults, and structural brain markers could partially mediate the association.

366 Effects of Acidosis Bout Events on Animal Growth and Development, and the Effectiveness of Liver Abscess-Controlling Antibiotic on Diminishing Its Incidence

Abstract Ruminal acidosis is a common metabolic disorder that affects feedlot and dairy cattle and occurs when the supply of organic acids from fermentation exceeds its absorption, accumulating acid content in the rumen. Virginiamycin (VM) has inhibitory effects on primary liver abscess-causing bacteria. In feedlot animals, dietary VM has been shown to reduce rumen acidosis and improve feed conversion actively. This study evaluated ruminal pH over 150 days on feed (DOF) of growing and finishing beef cattle and investigated the relationships between ruminal pH and growth and development outcomes and the effectiveness of the continuous or intermittent provision of VM in 120 Angus-crossbred steers. Steers received VM (240 mg/d) as follows: no VM (T000); VM in the last 50 d (T001); VM for the last 100 d (T011); VM in the first 50 d (T100); VM in the first 100 d (T110); and VM for 150 d (T111). Animals were fed a grower-type diet (metabolizable energy [ME]: 2.45 Mcal/kg; crude protein [CP]: 12.2 % dry matter basis [DM]) for 50 d before the adaptation of a finisher-type diet (ME: 2.60 Mcal/kg; CP: 10.6% DM) over a 17-d period. The finisher-type diet was fed for the remaining 84 days. On d -1 and d 82 each animal received an indwelling pH bolus to record ruminal pH at 10-min intervals. Acidosis bout event was categorized as if the pH stayed below 5.6 for 3 hours. Data were analyzed using a random coefficient statistical model, binary data was analyzed using the logit link function and correlations were analyzed using PROC CORR in SAS (Table 1). Duration under pH 5.8 and 5.6 tended to have a negative correlation with gain to feed (G/F; P ≤ 0.080), and % of the time that pH remained below 5.6 when under 5.8 was negatively correlated with G/F (P = 0.007) and tended to have a negative correlation with average daily gain (ADG; P = 0.081). Similarly, acidosis bouts event and duration of bout event (DURB) tended (P ≤ 0.074) to have a negative correlation with G/F, while ADG was negatively correlated (P = 0.035). The number of acidosis bout events and probability of acidosis bout events to occur increase linearly (R2 = 0.89, P &amp;lt; 0.001, and R2 = 0.77; P &amp;lt; 0.001, respectively) as DOF progressed. The probability of an acidosis bout event decreased by 46% for the T111 treatment compared with T000 (35.43% vs. 18.82%; P = 0.049). Acidosis bout event seems to affect the growth and development of beef steers negatively, and it appears to be more critical as DOF progress. Administration of VM at 240 mg/d throughout the whole feeding period seems to reduce the incidence of acidosis bout events.

Effectiveness of Protective Measures and Rules in Reducing the Incidence of Injuries in Combat Sports: A Scoping Review.

In recent years, much effort has been made to reduce the injury rate in combat sports. However, the question remains to what extent these measures are effective. Analysis of studies could provide evidence of the effectiveness of measures aimed at reducing the incidence of injuries. This scoping review aims (1) to map research articles dealing with the effectiveness of proper use of protective measures in reducing the incidence of injuries in combat sports; (2) to investigate to what extent the proper use of protective measures and compliance with sports rules help to reduce the incidence of injuries in combat sports; and (3) to identify gaps in the existing literature and suggest future research on this topic. The literature search was conducted on articles published between 2010 and 2023. The main inclusion criteria were studies investigating the effect of sports rules and protective equipment used during training or competition in combat sports on reducing the incidence of injuries. After meeting the criteria, only seven articles from boxing, karate, and taekwondo were included in this study. Results showed that mandatory head guards, along with modern thicker gloves, significantly reduced the rate of knockouts (KOs) and head injuries in boxing despite an increase in the number of head blows. However, the number of facial cuts increased significantly due to the removal of head guards as a piece of mandatory equipment. The use of mouth guards has significantly reduced the number of oral injuries. Changes in rules, such as shortening the duration of bouts, along with the introduction of greater competencies of referees in the supervision of bouts (the standing count, outclassed rule, and medical stops) have helped to reduce the rate of injuries in boxing. The application of a computerised scoring system also contributed to the rate of injuries reduction. The increase in the number of weight divisions had the same effect on U21 karate athletes. However, a higher incentive to attack the head area in taekwondo did not increase the incidence of injuries in youth athletes. It can be concluded that the proper use of protective measures (head and mouth guards) in combination with the rules established for health protection (higher competencies of referees and more weight divisions in competitions) effectively reduces the occurrence of injuries in combat sports. In all Olympic combat sports, the injury incidence should be regularly assessed using the Injury Incidence Rate (IIR) per 1000 min exposures (MEs). Nonetheless, further studies are needed to monitor how established rules (e.g., prohibited behaviour) affect the IIRs.

The Effects of Acute Bouts of Aerobic Exercise on Adipokine Concentrations in Individuals with Moderate Stages of Chronic Kidney Disease

This study examined the effects of two different acute bouts of treadmill running (e.g., steady-state moderate-intensity exercise (SSE) and high-intensity interval exercise (HIIE)) on adipokine (e.g., adiponectin, leptin, and omentin) concentrations in individuals with moderate stages of chronic kidney disease (CKD). Fourteen participants (8 females and 6 males) (age 58.7 ± 9.7, height (cm) 168.5 ± 9.7, weight (kg) 83.5 ± 18.2) were classified as having moderate stages of CKD (stages G3a and G3b; estimated glomerular filtration rate (eGFR) between 59 and 30 mL/min/1.73 m2). Participants completed 30 min of either SSE at 65% oxygen consumption reserve (VO2R) or HIIE for 3 min at a 90% VO2R separated by 2 min of slow walking (20% VO2R) in a randomized, crossover design on a treadmill. Venous blood samples were obtained at baseline, 1 h, and 24 h post exercise. Data were analyzed using a two by three repeated measures ANOVA (p &lt; 0.05). There were no significant differences in adiponectin (p &lt; 0.353), leptin (p &lt; 0.084), and omentin (p &lt; 0.235) concentrations between SSE and HIIE. Similarly, no significant differences were seen between the sampled time points for either aerobic exercise condition. In conclusion, this study demonstrated there were no changes in adiponectin, leptin, or omentin concentrations when performing an acute bout of HIIE or SSE for 30 min, at 1 or 24 h post exercise. Future studies should seek to either increase the duration of the exercise bout or identify different adipokines to examine for patients experiencing moderate stages of CKD.

Ready, Set, Move! Tracking Children's Modified Ride-On Car Use With a Custom Data Logger.

To create and implement a next-generation, custom data logger to automatically track modified ride-on car (MROC) use in home and community settings, establish feasibility of long-term remote collection of community MROC use data, describe trends of MROC use, and explore parent perception of the MROC. In this descriptive study, a custom data logger was constructed and integrated into MROCs using an Arduino Pro-Mini microprocessor to capture real-time use data remotely. It is feasible to automatically track MROC use in home and community settings. On average, MROC use trends appear consistent with caregiver reports and show higher initial use with steadily decreasing frequency over time, and varying bout duration and play session length, despite favorable caregiver perceptions of the cars. Remote tracking of MROC use may decrease burden on busy families and provide clinicians with valuable technology use data.

Effects of Different Recovery Duration on External and Internal Load Measures during Bouts of Small-Sided Games.

The aim of this study was to analyse the effects of different recovery times between bouts of small-sided games (SSG) on external and internal load variables in semi-professional soccer players. Sixteen male semi-professional soccer players performed three 4 vs. 4 + goalkeeper SSG training sessions, each with different recovery bout duration: short (1 min) (SSG1), medium (2 min) (SSG2), and long (4 min) (SSG4). Time motion and neuromuscular measures were collected during all SSGs, in addition, the rating of perceived exertion (RPE) was determined at the end of the last bout of each SSG. Results showed a significant increase in the total number of accelerations (p = 0.016, ES = 0.97, large) and decelerations (p = 0.022, ES = 0.81, large) in SSG4 compared to SSG1. In terms of the internal load, SSG2 showed significantly higher RPE values (p = 0.011, ES = 1.00, large) in comparison with SSG1. If the sessions' focus is on neuromuscular training, longer recovery times between SSG bouts should be used. Conversely, if the aim is to reach a higher total and running distance at different intensities, a 2-min recovery period between bouts may be more appropriate.

Distinct competitive impacts of palatability of taste stimuli on sampling dynamics during a preference test.

Food or taste preference tests are analogous to naturalistic decisions in which the animal selects which stimuli to sample and for how long to sample them. The data acquired in such tests, the relative amounts of the alternative stimuli that are sampled and consumed, indicate the preference for each. While such preferences are typically recorded as a single quantity, an analysis of the ongoing sampling dynamics producing the preference can reveal otherwise hidden aspects of the decision-making process that depend on its underlying neural circuit mechanisms. Here, we perform a dynamic analysis of two factors that give rise to preferences in a two-alternative task, namely the distribution of durations of sampling bouts of each stimulus and the likelihood of returning to the same stimulus or switching to the alternative-that is, the transition probability-following each bout. The results of our analysis support a specific computational model of decision making whereby an exponential distribution of bout durations has a mean that is positively correlated with the palatability of that stimulus but also negatively correlated with the palatability of the alternative. This impact of the alternative stimulus on the distribution of bout durations decays over a timescale of tens of seconds, even though the memory of the alternative stimulus lasts far longer-long enough to impact the transition probabilities upon ending bouts. Together, our findings support a state transition model for bout durations and suggest a separate memory mechanism for stimulus selection. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Association of physical activity with endothelial dysfunction among adults with and without chronic kidney disease: The Maastricht Study

Background and aimsPhysical activity (PA) constitutes an established protective factor while sedentary behavior (SB) an emerging independent risk factor for cardiovascular diseases. This study evaluated the association of PA and SB with endothelial dysfunction (ED) depending on kidney function status. MethodsCross-sectional data from the prospective, population-based Maastricht Study were used. PA and SB were measured using the ActivPAL3 accelerometer 24h/day for eight consecutive days. ED was evaluated by plasma levels of soluble vascular cell adhesion protein-1, intercellular adhesion molecule-1, E-selectin and von Willebrand factor, which were combined into an ED score with higher values depicting higher ED. ResultsOverall, 2,668 participants, 323 with chronic kidney disease, were included. In normal kidney function individuals, the ED score presented a significant negative association with total, lower-intensity and moderate-to-vigorous PA duration and a positive association with total sedentary time, sedentary breaks and sedentary bout duration. In participants with chronic kidney disease, a significant negative association of ED score with total [β: -4.42, 95% confidence intervals (95% CI): -7.98; −0.87] and lower-intensity (β: -7.08, 95% CI: -13.41; −0.74) PA duration, as well as a positive association of ED score with sedentary bout duration (β: 43.72, 95% CI: 9.85; 77.59) were noted. The strength of associations did not significantly differ across kidney function subgroups (p > 0.05). ConclusionsThis analysis showed that PA duration is inversely associated with ED both among patients with normal kidney function and chronic kidney disease. In chronic kidney disease, longer sedentary bouts were associated with greater endothelial dysfunction.

Effects of Cymatocarpus solearis (Trematoda: Brachycoeliidae) on its second intermediate host, the Caribbean spiny lobster Panulirus argus.

Many digenean trematodes require three hosts to complete their life cycle. For Cymatocarpus solearis (Brachycoeliidae), the first intermediate host is unknown; the Caribbean spiny lobster Panulirus argus is a second intermediate host, and the loggerhead turtle Caretta caretta, a lobster predator, is the definitive host. Trophically-transmitted parasites may alter the behavior or general condition of intermediate hosts in ways that increase the hosts' rates of consumption by definitive hosts. Here, we examined the effects of infection by C. solearis on P. argus by comparing several physiological and behavioral variables among uninfected lobsters (0 cysts) and lobsters with light (1-10 cysts), moderate (11-30 cysts), and heavy (>30 cysts) infections. Physiological variables were hepatosomatic index, growth rate, hemocyte count, concentration in hemolymph of cholesterol, protein, albumin, glucose, dopamine (DA) and serotonin (5-HT). Behavioral variables included seven components of the escape response (delay to escape, duration of swimming bout, distance traveled in a swimming bout, swim velocity, acceleration, force exerted, and work performed while swimming). There was no relationship between lobster size or sex and number of cysts. Significant differences among the four lobster groups occurred only in concentration of glucose (lower in heavily infected lobsters) and 5-HT (higher in heavily and moderately infected lobsters) in plasma. As changes in 5-HT concentration can modify the host's activity patterns or choice of microhabitat, our results suggest that infection with C. solearis may alter the behavior of spiny lobsters, potentially increasing the likelihood of trophic transmission of the parasite to the definitive host.

Characterizing Walking Behaviors in Aged Residential Care Using Accelerometry, With Comparison Across Care Levels, Cognitive Status, and Physical Function: Cross-Sectional Study.

Walking is important for maintaining physical and mental well-being in aged residential care (ARC). Walking behaviors are not well characterized in ARC due to inconsistencies in assessment methods and metrics as well as limited research regarding the impact of care environment, cognition, or physical function on these behaviors. It is recommended that walking behaviors in ARC are assessed using validated digital methods that can capture low volumes of walking activity. This study aims to characterize and compare accelerometry-derived walking behaviors in ARC residents across different care levels, cognitive abilities, and physical capacities. A total of 306 ARC residents were recruited from the Staying UpRight randomized controlled trial from 3 care levels: rest home (n=164), hospital (n=117), and dementia care (n=25). Participants' cognitive status was classified as mild (n=87), moderate (n=128), or severe impairment (n=61); physical function was classified as high-moderate (n=74) and low-very low (n=222) using the Montreal Cognitive Assessment and the Short Physical Performance Battery cutoff scores, respectively. To assess walking, participants wore an accelerometer (Axivity AX3; dimensions: 23×32.5×7.6 mm; weight: 11 g; sampling rate: 100 Hz; range: ±8 g; and memory: 512 MB) on their lower back for 7 days. Outcomes included volume (ie, daily time spent walking, steps, and bouts), pattern (ie, mean walking bout duration and alpha), and variability (of bout length) of walking. Analysis of covariance was used to assess differences in walking behaviors between groups categorized by level of care, cognition, or physical function while controlling for age and sex. Tukey honest significant difference tests for multiple comparisons were used to determine where significant differences occurred. The effect sizes of group differences were calculated using Hedges g (0.2-0.4: small, 0.5-0.7: medium, and 0.8: large). Dementia care residents showed greater volumes of walking (P<.001; Hedges g=1.0-2.0), with longer (P<.001; Hedges g=0.7-0.8), more variable (P=.008 vs hospital; P<.001 vs rest home; Hedges g=0.6-0.9) bouts compared to other care levels with a lower alpha score (vs hospital: P<.001; Hedges g=0.9, vs rest home: P=.004; Hedges g=0.8). Residents with severe cognitive impairment took longer (P<.001; Hedges g=0.5-0.6), more variable (P<.001; Hedges g=0.4-0.6) bouts, compared to those with mild and moderate cognitive impairment. Residents with low-very low physical function had lower walking volumes (total walk time and bouts per day: P<.001; steps per day: P=.005; Hedges g=0.4-0.5) and higher variability (P=.04; Hedges g=0.2) compared to those with high-moderate capacity. ARC residents across different levels of care, cognition, and physical function demonstrate different walking behaviors. However, ARC residents often present with varying levels of both cognitive and physical abilities, reflecting their complex multimorbid nature, which should be considered in further work. This work has demonstrated the importance of considering a nuanced framework of digital outcomes relating to volume, pattern, and variability of walking behaviors among ARC residents.

Patterns of sedentary behaviour in adults with acute insomnia derived from actigraphy data.

Sleep disorders, such as insomnia, have been associated with extended periods of inactive, sedentary behaviour. Many factors contribute to insomnia, including stress, irregular sleep patterns, mental health issues, inadequate sleeping schedules, diseases, neurological disorders and prescription medications. Identification of the patterns of sedentary time and its duration in adults with acute insomnia and healthy controls to determine the statistically significant sedentary bouts; comparison of the sedentary behaviour patterns in acute insomnia adults with healthy controls. We investigate the daytime actigraphy data and identify temporal patterns of inactivity among adults with acute insomnia and healthy adults. Seven days of actigraphy data were utilised to calculate sedentary time and bouts of variable duration based on a threshold of activity counts (<100 counts per minute). Statistical analysis was applied to investigate sedentary bouts and total sedentary time during weekdays and weekend. A logistic regression model has been used to determine the significance of sedentary bouts. We found that individuals with acute insomnia accumulate a significant amount of their sedentary time in medium (6-30 minutes and 31-60 minutes) and longer (more than 60 minutes) duration bouts in comparison to healthy adults. Furthermore, a low p value for total sedentary time (2.54 ⋅ 10-4) association with acute insomnia supports the finding that acute insomnia individuals are significantly more engaged in sedentary activities compared to healthy controls. Also, as shown by the weekend vs weekday analysis, the physical and sedentary activity patterns of acute insomnia adults demonstrate higher variability during the weekdays in comparison to the weekend. The results of the present study demonstrate that adults with acute insomnia spend more time in low-intensity daily physical activities compared to healthy adults.

Joint modeling the frequency and duration of accelerometer-measured physical activity from a lifestyle intervention trial.

Physical activity (PA) guidelines recommend that PA be accumulated in bouts of 10 minutes or more in duration. Recently, researchers have sought to better understand how participants in PA interventions increase their activity. Participants can increase their daily PA by increasing the number of PA bouts per day while keeping the duration of the bouts constant; they can keep the number of bouts constant but increase the duration of each bout; or participants can increase both the number of bouts and their duration. We propose a novel joint modeling framework for modeling PA bouts and their duration over time. Our joint model is comprised of two sub-models: a mixed-effects Poisson hurdle sub-model for the number of bouts per day and a mixed-effects location scale gamma regression sub-model to characterize the duration of the bouts and their variance. The model allows us to estimate how daily PA bouts and their duration vary together over the course of an intervention and by treatment condition and is specifically designed to capture the unique distributional features of bouted PA as measured by accelerometer: frequent measurements, zero-inflated bouts, and skewed bout durations. We apply our methods to the Make Better Choices study, a longitudinal lifestyle intervention trial to increase PA. We perform a simulation study to evaluate how well our model is able to estimate relationships between outcomes.

White-tailed deer responses to acoustic predator cues are contingent upon past land use and contemporary fire regime

Abstract Prey can assess the immediate risk of predation by detecting cues of predator presence, and it is expected that prey should invest in costly antipredator behaviors when a cue of predator presence is detected. Features of the habitat in which the cue is detected, such as vegetative concealment, serve as indirect cues of risk and can mediate how prey respond to direct cues of predator presence. Past agricultural land use and contemporary fire regimes are common disturbances that may modify prey perceptions of risk and could, therefore, alter prey responses to direct cues of predator presence. We examined whether the overlap of these two disturbances affected white-tailed deer (Odocoileus virginianus) responses to cues of predator presence by measuring deer vigilance and foraging bout duration in response to coyote (Canis latrans) vocalizations across 20 woodlands that varied in past land use and contemporary fire regime. Frequent fire regimes consistently increased deer visibility to predators across both land-use history contexts. Deer exhibited no behavioral response to the predator cue in habitats containing infrequent fire regimes or agricultural legacies. Deer responded to the cue in frequently burned woodlands without agricultural legacies through increased vigilance and time spent at a foraging location. These findings reveal that land-use legacies and contemporary fire regimes can mediate how prey respond to direct cues of risk. They also suggest that prey may balance the uncertainty associated with cues of predation risk with the urgency of responding to a potential attack by being vigilant and remaining in place.

Sedentary Bout Patterns and Metabolic Health in the Hispanic Community Health Study/Study of Latino Youth (SOL Youth).

Background There is limited evidence on the potential negative metabolic health impacts of prolonged and uninterrupted sedentary bouts in structurally disadvantaged youth. This study investigated associations between sedentary bout variables and metabolic health markers in the Hispanic Community Health Study/SOL Youth (Study of Latino Youth). Methods and Results SOL Youth was a population-based cohort of 1466 youth (age range, 8-16 years; 48.5% female); 957 youth were included in the analytic sample based on complete data. Accelerometers measured moderate-to-vigorous physical activity (MVPA), total sedentary time, and sedentary bout patterns (daily time spent in sedentary bouts ≥30 minutes, median sedentary bout duration, and number of daily breaks from sedentary time). Clinical measures included body mass index, waist circumference, fasting glucose, glycated hemoglobin, fasting insulin, and the homeostasis model assessment of insulin resistance. After adjusting for sociodemographics, total sedentary time, and MVPA, longer median bout durations and fewer sedentary breaks were associated with a greater body mass index percentile (bbouts=0.09 and bbreaks=-0.18), waist circumference (bbouts=0.12 and bbreaks=-0.20), and fasting insulin (bbouts=0.09 and bbreaks=-0.21). Fewer breaks were also associated with a greater homeostasis model assessment of insulin resistance (b=-0.21). More time in bouts lasting ≥30 minutes was associated with a greater fasting glucose (b=0.18) and glycated hemoglobin (b=0.19). Conclusions Greater accumulation of sedentary time in prolonged and uninterrupted bouts had adverse associations with adiposity and glycemic control over and above total sedentary time and MVPA. Findings suggest interventions in Hispanic/Latino youth targeting both ends of the activity spectrum (more MVPA and less prolonged/uninterrupted sedentary patterns) may provide greater health benefits than those targeting only MVPA.