Nighttime Sleep Awakening Frequency and Its Consistency Predict Future Academic Performance in College Students

Although the relations between sleep and academic performance have been extensively examined, how sleep predicts future academic performance (e.g., 2 -3 years) remains to be further investigated. Using wearable smartwatches and a self-report questionnaire, we tracked sleep activities of 45 college students over a period of approximate half a month to see whether their sleep activities predicted their academic performance, which was estimated by grade point average (GPA). Results showed that both nighttime sleep awakening frequency and its consistency in the tracking period were not significantly correlated with the GPA for the courses taken in the semester during sleep tracking (current GPA). However, both nighttime sleep awakening frequency and its consistency inversely predicted the GPA for the rest of the courses taken after that semester (future GPA). Moreover, students with more difficulty staying awake throughout the day obtained lower current and future GPAs, and students with lower inconsistency of sleep quality obtained lower future GPA. Together, these findings highlight the importance of nighttime sleep awakening frequency and consistency in predicting future academic performance and emphasize the necessity of assessing the consistency of sleep measures in future studies.

A Satellite-linked Tag for the Long-term Monitoring of Diving Behavior in Large Whales

Despite spending much of their time on activities underwater, the technology in use to track whales over large geographic ranges via satellite has been largely limited to locational data, with most applications focusing on characterizing their horizontal movements. We describe the development of the RDW tag, a new Argos-based satellite telemetry device that incorporates sensors for monitoring the movements and dive behavior of large whales over several months without requiring recovery. Based on an implantable design, the tag features a saltwater conductivity switch, a tri-axial accelerometer, and an optional pressure transducer, along with onboard software for data processing and detection of behavioral events or activities of interest for transmission. We configured the software to detect dives and create per-dive summaries describing behavioral events associated with feeding activities in rorqual whales. We conducted a validation by proxy of the dive summary and event detection algorithms using data from a medium-duration archival tag. The dive summary algorithm accurately reported dive depth and duration, while the accuracy of the lunge-feeding event detection algorithm was dependent on the precision of the accelerometer data that was used, with a predicted accuracy of 0.74 for correctly classifying feeding dives from 1/64-G precision data and 0.95 from 1-mG precision data. We also present data from field deployments of the tag on seven humpback whales ( Megaptera novaeangliae ) and one blue whale ( Balaenoptera musculus ). The eight tags transmitted over a median tracking period of 17.5 d (range: 3.9-76.4 d) across both species. The median proportion of the tracking period summarized by received dives for the eight tags was 50.4% (range: 11.1-88.7%). The median number of received dives per day was 76.5 (range: 1-191). The results documented diel and longer-term variability in diving and feeding behavior, showing marked differences within and among individuals tracked contemporaneously. By monitoring the per-dive behavior of large whales over multi-month timescales of movement, the RDW tags provided some of the first assessments of previously unobservable behaviors across entire geographic ranges, linking local-scale behavior to broader, ecosystem-scale processes. The RDW tag extends the applications of whale satellite telemetry to new areas of physiology, ecology, and conservation.

A pilot study on the home range and movement patterns of the Andean Fox Lycalopex culpaeus (Molina, 1782) in Cotopaxi National Park, Ecuador

This study reports movement patterns and home range estimates of an Andean fox (Lycalopex culpaeus) in Cotopaxi National Park in Ecuador, representing the first GPS-tagging of the species. The GPS functioned well during the 197-day tracking period. Home range sizes ranged between 4.9 and 8.1 km2, depending on the estimation method. Movement speeds averaged 0.17 km/h at day versus 0.87 km/h at night, and distance traveled averaged 0.23 km at day versus 0.89 km at night. These preliminary results highlight the importance of collecting unbiased, high-quality data which enables an enhanced understanding on mammal behavior and human/animal interaction.

Home range and movement patterns of the Andean Fox Lycalopex culpaeus (Molina 1782) in Cotopaxi National Park, Ecuador

Here we report movement patterns and home range estimates of an Andean fox (Lycalopex culpaeus) in Cotopaxi National Park, representing the first GPS-tagging of the species. The GPS functioned well during the 197-day tracking period. Home range sizes ranged between 4.9 - 8.1 km2, depending on the estimation method. Movement speeds averaged 0.17 km/hr. at day vs. 0.87 km/hr. at night, and distance traveled averaged 0.23 km at day vs. 0.89 km at night. These results are part of research in Ecuador studying the behavior and interactions of mammals with other species and humans.

Use of Wearable Activity Tracker in Patients With Cancer Undergoing Chemotherapy: Toward Evaluating Risk of Unplanned Health Care Encounters

PURPOSE Unplanned health care encounters (UHEs) such as emergency room visits can occur commonly during cancer chemotherapy treatments. Patients at an increased risk of UHEs are typically identified by clinicians using performance status (PS) assessments based on a descriptive scale, such as the Eastern Cooperative Oncology Group (ECOG) scale. Such assessments can be bias prone, resulting in PS score disagreements between assessors. We therefore propose to evaluate PS using physical activity measurements (eg, energy expenditure) from wearable activity trackers. Specifically, we examined the feasibility of using a wristband (band) and a smartphone app for PS assessments. METHODS We conducted an observational study on a cohort of patients with solid tumor receiving highly emetogenic chemotherapy. Patients were instructed to wear the band for a 60-day activity-tracking period. During clinic visits, we obtained ECOG scores assessed by physicians, coordinators, and patients themselves. UHEs occurring during the activity-tracking period plus a 90-day follow-up period were later compiled. We defined our primary outcome as the percentage of patients adherent to band-wear ≥ 80% of 10 am to 8 pm for ≥ 80% of the activity-tracking period. In an exploratory analysis, we computed hourly metabolic equivalent of task (MET) and counted 10 am to 8 pm hours with > 1.5 METs as nonsedentary physical activity hours. RESULTS Forty-one patients completed the study (56.1% female; 61.0% age 40-60 years); 68% were adherent to band-wear. ECOG score disagreement between assessors ranged from 35.3% to 50.0%. In our exploratory analysis, lower average METs and nonsedentary hours, but not higher ECOG scores, were associated with higher 150-day UHEs. CONCLUSION The use of a wearable activity tracker is generally feasible in a similar population of patients with cancer. A larger randomized controlled trial should be conducted to confirm the association between lower nonsedentary hours and higher UHEs.

Wearable Hearing Assist System to Provide Hearing-Dog Functionality

This study developed a wearable hearing-assist system that can identify the direction of a sound source while using short-term interaural time differences (ITDs) of sound pressure and convey the sound source direction to a hearing-impaired person via vibrators that are attached to his or her shoulders. This system, which is equipped with two microphones, could dynamically detect and convey the direction of front, side, and even rear sound sources. A male subject was able to turn his head toward continuous or intermittent sound sources within approximately 2.8 s when wearing the developed system. The sound source direction is probably overestimated when the interval between the two ears is smaller. When the subject can utilize vision, this may help in tracking the location of the target sound source, especially if the target comes into view, and it may shorten the tracking period.

Proceedings of the First International Snakehead Symposium

<em>Abstract.</em>—Understanding the diel activity of a species can shed light on potential interactions with other species and inform management practices. To understand the diel activity of Northern Snakehead <em>Channa argus</em>, feeding habits and movement patterns were observed. Two hundred seventy-three Northern Snakehead were captured by boat electrofishing during May and June of 2007 and 2008. Their gut contents were extracted and preserved. The level of digestion of each prey item was estimated from fresh (1) to >50% digested (4) or empty (5). Random forest models were used to predict feeding activity based on time of day, tide level, date, water temperature, fish total length, and sex. Diel movement patterns were assessed by implanting Northern Snakehead with radio transmitters and monitoring them every 1.5 h for 24 h in both March and July 2007. Movement rates were compared between March and July and among four daily time periods. Independent variables accounted for only 6% of the variation in feeding activity; however, temporal feeding patterns were apparent. No fresh items were observed in guts between 12:30 and 7:30 am, and the proportion of empty stomachs increased at the end of May coinciding with the onset of spawning. Overall, fish moved greater distances during the July tracking period compared to March. Fish showed a greater propensity to move during daylight hours than at night during the March tracking period. A similar but nonsignificant (<EM>P </EM>> 0.05) pattern was observed in July. Movement and feeding data both indicated greater activity during daylight hours than at night, suggesting that Northern Snakehead is a diurnal species. Based on our preliminary findings, we hypothesize that a) diurnal species are more susceptible than nocturnal species to predation by Northern Snakehead and b) Northern Snakehead are more likely to compete for food with diurnal than nocturnal predators.

Compensation for Input Nonlinearities in Repetitive Control Systems Based on Improved Equivalent-Input-Disturbance Approach

The equivalent-input-disturbance (EID) approach is used to deal with the problem of tracking period signals for a plant with input actuator nonlinearities in a repetitive control system. First, an EID estimator is constructed by taking the full advantage of an extended state observer (ESO), the design of the ESO is explained. Next, an EID estimate, which represents the synthetic effect of the nonlinearities, is incorporated into a repetitive control law to compensate for the effect caused by the nonlinearities. This method does not require any prior information about the nonlinearities. It guarantees perfect tracking for periodic reference input and satisfactory compensation for input nonlinearities at the same time. Finally, simulation and experimental results show the effectiveness of the method.

Effect of terrain heterogeneity on feeding site selection and livestock movement patterns

Feeding site selection is a critical part of livestock foraging that can constrain and/or increase the choices available during diet selection. When livestock choose new feeding sites, vegetation and nutrient profiles can differ from other areas, especially in heterogeneous environments with rugged terrain. Correspondingly, livestock should remain longer in feeding sites in rugged heterogeneous pastures than in homogeneous pastures where animals may alternate among feeding sites to facilitate diet mixing and to prevent satiation. The objective of this study was evaluate how terrain and corresponding heterogeneity may affect the sequence and pattern of feeding site selection of free-roaming livestock. Grazing patterns of mature cows were evaluated on six ranches located in Arizona, Montana and New Mexico. In total, 11–19 cows were tracked for 1–3-month periods at each ranch by using global positioning system (GPS) collars. Positions were recorded at 10- or 15-min intervals and used to identify where cows grazed during the early morning (0500 hours to 1000 hours). Pastures (336–9740 ha) at each ranch were divided into seven to nine sections (48–1082 ha) as an indicator of feeding sites. Classification was based on cattle density and topographical and vegetation types. Sequences of daily section selection were evaluated using transition matrixes. For all ranches, the sequence of section selection differed from what would be expected by chance, indicating that the section selected on the following day depended on the section selected on the previous day. For ranches with relatively gentle terrain, cattle selected different feeding sites ~70% of the tracking period. In contrast, cows at the ranch with the largest pasture and enclosing both mountainous and gentle terrain stayed in the same feeding site for over 10 successive days for 42% of the tracking period. Smaller pastures with only mountainous terrain were intermediate. Cows grazing gentle topography and relatively homogeneous vegetation alternated among feeding sites (sections in the present study) more frequently than cows grazing pastures with more rugged topography and more heterogeneous vegetation. This pattern could help livestock mix forages and select a more diverse diet.

Vývoj hráčské struktury v družstvech ženské basketbalové Excelsior ligy se zaměřením na věk a státní příslušnost

This article looks at the evolution of structure teams in the top Czech women‘s basketball competition - Excelsior league. Tracking period is since seasons 1998/99 to 2010/11. The cardinal method of this research is based on content analysis of game match statistics – these include the number of female players (their age), minutes played, points scored and coefficient of usefulness. The sample of players is classified into three groups (Czech players younger than twenty years, Czech players twenty years old and older, foreign players). The results confirm the expected increase of number of foreign players as well as continuously growing impact on the game, in our study presented a coefficient of utility players. The trend of integration into Czech female players younger than 20 years is inversely dependent on the number of Czech female players older than 20 years. Our assumptions were confirmed. The article refers to the change of the team constitution.