Intra- and Inter-Day Variability in Recess Physical Activity Over One Week in Young Children

Researchers interested in outdoor free play (i.e., recess) may collect data on total (light-to-vigorous) physical activity (TPA) during a single recess period or over several days, yet little is known about intra- and inter-day variability or whether individual recess periods or days are representative of “typical” recess TPA. PURPOSE: The purpose of the current study was to explore variability in TPA across a week of recess periods with the overarching goal of identifying how many recess periods may be needed to represent weekly recess TPA. METHODS: Children (n=29; age=2-6 y) from two on-campus early childhood education programs which shared a schoolyard wore a triaxial GENEActiv accelerometer at the right hip during school hours for a week. Euclidean norm minus one per 5-sec was calculated and used to estimate percent of recess time spent in TPA. A mixed effects model compared TPA by day and recess time of day (fixed effects) with child as a random effect. We averaged TPA for each of the 13 individual recesses, scheduled recess time (morning, afternoon, end of day), and day (Monday-Friday). T-tests were used to compare TPA during individual recess periods, scheduled recess times, and days to overall average weekly recess TPA. P-values were adjusted for multiple comparisons using the Bonferroni correction.RESULTS: Overall weekly recess TPA was 62.3±9.7%. TPA ranged from 47.3-82.5% across the 13 individual recess periods, 56.0-63.1% across scheduled recess times, and 54.0-69.2% across days. In the mixed effects model, there was a significant effect of day, but not scheduled recess time. Post-hoc comparisons indicated Friday TPA was different from Monday (p=0.006), Tuesday (pCONCLUSIONS: Although an individual recess period is insufficient, capturing recess PA over a single day or a single time of day (e.g., morning recess for a week) is representative of weekly recess TPA at the group level, although TPA may vary by day for individuals. This could be a less burdensome and more efficient method of characterizing recess TPA when informing and assessing interventions

Movement of Smallmouth Bass within the Beaver Island Archipelago, Northern Lake Michigan.

Fish movement may vary across a wide array of aquatic ecosystems and may be related to the overall size of the system inhabited. We investigated movement of smallmouth bass in Lake Michigan because this information is lacking for larger systems. A total of 16 smallmouth bass were surgically implanted with ultrasonic transmitters within the Beaver Archipelago, northern Lake Michigan. During 2007–2008, a maximum of one location per individual was recorded daily during three specific tracking periods – pre-spawn, spawning, and post-spawn – to determine diurnal movement patterns. Movement was evaluated as site fidelity, minimum displacement rate,maximumexcursion rate, and distance from shore. Smallmouth bass exhibited greatermaximum excursion rates during the spawn period compared to pre-spawn. Movement rates did not differ between tracking periods; however, movement rates were greater during the spawn period in 2007 than 2008. Both sexes moved further offshore to deeper water during post-spawn, but females were located further offshore than males during this period. Annual site fidelity was more evident during post-spawn than during spawning for both sexes. Two smallmouth bass emigrated outside of the Archipelago, suggesting this population may be more “open” in terms of individuals moving throughout northern Lake Michigan than previously thought. These results indicate smallmouth bass may move greater distances in larger aquatic systems and therefore larger management units (in terms of total area) should be established in Lake Michigan to account for these greater excursion distances

Movement of Smallmouth Bass within the Beaver Island Archipelago, Northern Lake Michigan.

Fish movement may vary across a wide array of aquatic ecosystems and may be related to the overall size of the system inhabited. We investigated movement of smallmouth bass in Lake Michigan because this information is lacking for larger systems. A total of 16 smallmouth bass were surgically implanted with ultrasonic transmitters within the Beaver Archipelago, northern Lake Michigan. During 2007–2008, a maximum of one location per individual was recorded daily during three specific tracking periods – pre-spawn, spawning, and post-spawn – to determine diurnal movement patterns. Movement was evaluated as site fidelity, minimum displacement rate,maximumexcursion rate, and distance from shore. Smallmouth bass exhibited greatermaximum excursion rates during the spawn period compared to pre-spawn. Movement rates did not differ between tracking periods; however, movement rates were greater during the spawn period in 2007 than 2008. Both sexes moved further offshore to deeper water during post-spawn, but females were located further offshore than males during this period. Annual site fidelity was more evident during post-spawn than during spawning for both sexes. Two smallmouth bass emigrated outside of the Archipelago, suggesting this population may be more “open” in terms of individuals moving throughout northern Lake Michigan than previously thought. These results indicate smallmouth bass may move greater distances in larger aquatic systems and therefore larger management units (in terms of total area) should be established in Lake Michigan to account for these greater excursion distances

Fish Assemblage Shifts and Population Dynamics of Smallmouth Bass (Micropterus dolomieu) in the Beaver Archipelago, Northern Lake Michigan: A Comparison Between Historical and Recent Time Periods Amidst Ecosystem Changes.

The ecological and economic importance of Great Lakes nearshore areas and the paucity of information on nearshore Lake Michigan fish assemblages prompted us to document changes that occurred from a historical time period (1969–1972, 1975, 1977, and 1984) to a recent period (2005–2008) in a nearshore northern Lake Michigan (Beaver Archipelago) fish assemblage, with an emphasis on smallmouth bass Micropterus dolomieu. From historical to recent periods, the Beaver Archipelago fish assemblage shifted from predominantly brown bullheads Ameiurus nebulosus to predominantly smallmouth bass. Relative abundance of brown bullheads and white suckers Catostomus commersonii declined from historical to recent time periods, as did overall species richness. The relative abundance, recruitment variability, and mortality rates of smallmouth bass have not significantly changed since the historical time period, whereas both condition (ages 5–7) and growth (ages 2–7) of this species have significantly increased. Our results suggest that the smallmouth bass population in the Beaver Archipelago area has not been negatively affected by recent ecological changes (i.e., declining primary productivity, increasing benthic invertebrate densities, increasing numbers of double-crested cormorants Phalacrocorax auritus, and increasing introductions of nonnative species). The smallmouth bass is currently the dominant nearshore species and remains a critical component of the nearshore fish assemblage in northern Lake Michigan

Monitoring wolf populations using howling points combined with sign survey transects

Wolves respond to simulated howling, especially during the mating and breeding seasons. Simulated howling points are, therefore, commonly used by many wolf researchers around the world to estimate pack numbers in a given area. A large amount of information is available on various pack breeding areas in Asturias, the only region in north-western Spain where the Iberian wolf (Canis lupus signatus, Cabrera 1907) is not classed as a game species. Wolf research began there in the early 1980s. We present the results of the latest study on population status, conducted between July and November, 2001. Using sampling transects to detect wolf scat and scratch marks and designated howling and observation points, twenty one (21) wolf packs were definitely located, with two others considered “likely”. Nineteen (19) packs were detected using howling points (n=314). The results of this study show that simulated howling points and sampling transects are reliable and inexpensive way of detecting wolf packs

Nitrogen and Sulfur Concentrations and Flow Rates of Corn Wet‐Milling Streams

Nitrogen (N) and sulfur (S) concentrations can affect the market value of coproducts from corn wet‐milling. The composition of parent streams would be expected to affect composition of the resulting coproducts but there are few published data available to examine this relationship. Concentration and flow data are needed to determine which streams are important in modifying N and S coproduct concentrations. The objective was to measure concentrations and flows of N and S in corn wet‐milling streams. Samples were taken from 21 process streams from 3 wet‐milling plants during two periods of three weeks each; N and S concentrations of each sample were determined. There were large differences in N and S concentrations among processing streams; within most streams, N and S concentrations were similar among plants. Concentrations of N and S were related inversely to flow rates. Steepwater and gluten streams contained most of the N and S flow and provide an opportunity for modification. The process water stream carried large quantities of N and S and represents another opportunity for improving process efficiency and coproduct value.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141537/1/cche0260.pd

Psychological Abuse, Mental Health, and Acceptance of Dating Violence Among Adolescents

Purpose Existing literature indicates that acceptance of dating violence is a significant and robust risk factor for psychological dating abuse perpetration. Past work also indicates a significant relationship between psychological dating abuse perpetration and poor mental health. However, no known research has examined the relationship between acceptance of dating violence, perpetration of dating abuse, and mental health. In addition to exploring this complex relationship, the present study examines whether psychological abuse perpetration mediates the relationship between acceptance of dating violence and mental health (i.e., internalizing symptoms of depression, anxiety, and hostility). Methods Three waves of longitudinal data were obtained from 1,042 ethnically diverse high school students in Texas. Participants completed assessments of psychological dating abuse perpetration, acceptance of dating violence, and internalizing symptoms (hostility and symptoms of anxiety and depression). Results As predicted, results indicated that perpetration of psychological abuse was significantly associated with acceptance of dating violence and all internalizing symptoms. Furthermore, psychological abuse mediated the relationship between acceptance of dating violence and internalizing symptoms. Conclusions Findings from the present study suggest that acceptance of dating violence is an important target for the prevention of dating violence and related emotional distress

The Distribution Of Chlorine And Iodine In Soil In The Vicinity Of Lead Mining And Smelting Operations, Bixby Area, S.E. Missouri, U.S.A.

Iodine and Cl are enriched in soils in the vicinity of the Magmont and Buick lead mines near Bixby, southeastern Missouri. The enrichments, up to 5.6 ppm I and 305 ppm Cl, are against regional background of 1.26 ppm I and 41 ppm Cl. The area of highest I and Cl is thought to reflect a zone of base metal sulphide mineralization occurring about 400 m below the surface. Iodine and Cl are also enriched in soils immediately adjacent to a tailings pond, hence these elements would appear to be leached from this source. A zone of enhanced I values (up to 2.65 ppm I) to the north of a lead smelter is superimposed on a much larger zone of lead enrichment (up to 12,000 ppm Pb) and is thought to represent I released from sulphide ores on smelting. © 1988

Nuclear localization and function of polypeptide ligands and their receptors: a new paradigm for hormone specificity within the mammary gland?

The specific effects triggered by polypeptide hormone/growth factor stimulation of mammary cells were considered mediated solely by receptor-associated signaling networks. A compelling body of new data, however, clearly indicates that polypeptide ligands and/or their receptors are transported into the nucleus, where they function directly to regulate the expression of specific transcription factors and gene loci. The intranuclear function of these complexes may contribute to the explicit functions associated with a given ligand, and may serve as new targets for pharmacologic intervention

Optical properties of thin semiconductor device structures with reflective back-surface layers

Ultrathin semiconductor device structures incorporating reflective internal or back surface layers have been investigated recently as a means of improving photon recuperation, eliminating losses associated with free carrier absorption in conductive substrates and increasing the above bandgap optical thickness of thermophotovoltaic device structures. However, optical losses in the form of resonance absorptions in these ultrathin devices have been observed. This behavior in cells incorporating epitaxially grown FeAl layers and in devices that lack a substrate but have a back-surface reflector (BSR) at the rear of the active layers has been studied experimentally and modeled effectively. For thermophotovoltaic devices, these resonances represent a significant loss mechanism since the wavelengths at which they occur are defined by the active TPV cell thickness of {approximately} 2--5 microns and are in a spectral range of significant energy content for thermal radiators. This study demonstrates that ultrathin semiconductor structures that are clad by such highly reflective layers or by films with largely different indices of refraction display resonance absorptions that can only be overcome through the implementation of some external spectral control strategy. Effective broadband, below-bandgap spectral control using a back-surface reflector is only achievable using a large separation between the TPV active layers and the back-surface reflector