Rural children are more likely to live in cohabiting-couple households

As cohabiting increases nationwide, new data show that the growing rate of children in these households is most pronounced in rural areas. This brief analyzes recent U.S. Census Bureau data to explore these trends and patterns

MOTION ANALYSIS: ONE VERSUS TWO STRIDE ANALYSES

The purpose of this study was to analyze two consecutive strides and compare results of gait and posture between the first stride, second stride and mean of the two strides. Two strides were filmed and digitized for 36 children at both 100m and 900m on three separate occasions. Head and trunk f1exion, stride length, stride rate and double support time were recorded. No significant differences were found between the first, second and mean of the two strides for trunk! head flexion and stride length. Differences were recorded between the first and second stride in stride rate and double support time, although neither stride was significantly different from the mean of the two strides. It was concluded that only one stride need to be digitized for an accurate representation of posture and gait

EFFECTS OF BACKPACK DESIGN AND FATIGUE ON POSTURE IN CHILDREN

The purpose of this study was to determine which hip bell/frame sheet combination reduced postural changes associated with load carriage in children. Thirty-six 10·12 year olds walked 1000m around a track in 3 randomly assigned hip belt and frame sheet conditions. Two strides were digitized at 100 and 900m with mean head and trunk angles, as well as posture across the gait cycle recorded. Hip belt and frame sheet design did not alter head flexion separately, but interaction between the design features indicated less compromise in posture with the Back Balancer. The solid and padded frame sheet reduced counterbalance of the weight in the trunk

ARM SWING IN CHILDREN CARRYING BACKPACKS

Arm swing during walking helps maintain balance and reduce twisting of the trunk. By limiting horizontal excursions of the body, arm swing aids in maintaining horizontal velocity (Hinrichs, Cavanagh, & Williams, 1987). When arm swing is restricted, it is predicted that there will be a greater degree of torque placed on the vertebra, increasing pressure on the intervertebral discs (Jackson, 1983; Li et aI., 2001). This may be exaggerated when adding weight, specifically to the trunk, such as when carrying a backpack. Arm swing not only aHects torsion on the spine, it also influences the lower limbs. Reciprocal swinging of the arms has been directly tied to stride rate. As arm swing is restricted, stride rate tends 10 increase (Eke-Okoro, Gregoric, & Larsson, 1997). Increased vertical ground reaction forces have also been tied to fixed-arm walking (Li et aI., 2001). Li et al. (1996) found differences between adults and children 9 years of age as they corresponded to centre of pressure under the foot. These differences were attributed to torques induced by the lower limbs because arm swing was restricted in children's walking patterns. The purpose of this study was to determine the amount of arm swing in children during load carriage

Results of the REFLEX (Return Flux Experiment) Flight Mission

The numerous problems occurring in this first flight of the REFLEX experiment, both in the spacecraft and with the instrument package, seriously constrained the acquisition and analysis of data and severely limited the interpretation of the data that were obtained. Of these, the ambient helium measurements appear to be the most promising. They are summarized and discussed in Appendix A. Further analyses could be attempted to establish the correct values for the energy centers as they varied during the mission. In addition, an extensive laboratory recalibration on a high-speed beam system could in principle provide corrections to be used in analyzing and interpreting the returned data set. The unknown malfunction which generated the energy drift needs to be understood and corrected before the REFLEX experiment is reflown; some hardware modification, or at least retuning, is likely to be required

A compact time-of-flight mass spectrometer for high-flux cosmic dust analysis

Time‐of‐flight mass spectrometers on spacecraft are the most direct method for determining chemical composition of cosmic dust grains. Miniaturization of these instruments presents many challenges. Larger space‐charge effects, greater deviations from the paraxial approximation, and various ion‐optical aberrations negatively affect mass resolution in small time‐of‐flight instruments. We report on the building and testing of an instrument design that may reduce these effects. In addition to a linear reflectron, ions pass through a ring aperture that transmits only those ions with transverse velocity components that fall within a specific range. This novel design focuses ions onto a detector with greatly reduced spherical aberration. Space‐charge effects and the effects of impact plate cratering and grid scatter are also reduced using this design. Controlled impacts of iron microparticles at several km/s demonstrate instrument performance. This instrument is suited for characterization of cosmic dust in regions of very high dust flux, such as a comet flyby, and it may also have practical laboratory or field applications

Geology of the Maketu Area, Bay of Plenty, North Island, New Zealand. Sheet V14 1:50 000

The area covered in this report on the geology of Sheet V14 Maketu 1 :50 000 includes Motiti Island and a small triangular section of the Bay of Plenty coastal lowlands from the Kaituna River mouth to Pukehina Beach within the Maketu Basin, eastern North Island. Motiti Island is situated 12 km offshore from the Bay of Plenty coast and is an eroded remnant of a Pliocene (4.3-3.4 Ma) andesitic composite cone. It is a flat-lying island surrounded by cliffs up to 30 m high, and the highest point is 57 m above sea level. The island is constructed on a base of andesitic rocks that have been divided into two new formations, the Motiti Formation consisting of thick massive or platy jointed lava flows and volcanic breccias, and the Orongatea Formation comprising thin lava flows, volcanic breccias, lapilli tuffs, tuffs, and dikes that are considered to be proximal strombolian and phreatomagmatic deposits. The andesitic formations are unconformably overlain by a 20-m thick sequence of middle to late Quaternary volcanogenic sediments (fluviatile sands, silts, and gravels), which in turn are covered by a 6-m thick blanket of late Quaternary tephras including Rotoiti Tephra Formation at the base. Originally the island would have been manifested as an andesitic composite cone and tuff ring complex, but it is now characterised by the strong angular unconformity that truncates the older andesitic rocks, which have been planed flat, presumably by marine erosion. The andesites and basaltic andesites of Motiti Island have ages and geochemical compositions similar to those of the Waihi district and southern Coromandel Volcanic Zone. The Maketu peninsula (Town Point) forms a 67-m high headland on the Bay of Plenty coast. and is considered to be a horst, bounded by NE (035°)-striking normal faults and downfaulted blocks on both sides. The oldest rocks in the Maketu area are exposed in cliffs around the peninsula and consist of fluvial sands, silts, and gravels, aeolian sediments, and a 25-m thick lahar or lake-breakout flood deposit (Newdicks Formation, new) with a stratigraphic age of c. 0.25 Ma. The source of the lahar/flood deposit is unknown, but it contains clasts up to 7 m across of a densely welded ignimbrite that form a litter of boulders around the Maketu peninsula. The fluvial sediments are similar in rock type and stratigraphic position to those on Motiti Island, and both sequences have been included here in the Matua Subgroup. Intercalated with the sediments of the Matua Subgroup are thin Mid-Pleistocene pumiceous tephra fallout beds of the Huntress Creek and Kukumoa subgroups, and a c. 5-m thick non-welded ignimbrite identified as Mamaku lgnimbrite (c. 0.22 Ma). The uppermost part of the Matua Subgroup is marked by a well-developed, dark paleosol formed in clayey loess, and is Last Interglacial in age (c. 125 ka). The Maketu peninsula is capped by a 15-m thick sequence of late Quaternary pumiceous and unweathered to weakly weathered tephra beds that include Rotoiti Tephra Formation, four tephras of the Mangaone Subgroup, and numerous younger tephras derived from the volcanic centres of Okataina (ten tephras), Taupo (six tephras), and Tuhua (Mayor Island) (one or more tephras), and minor loess deposits. The youngest of these tephras include the white, pumiceous rhyolitic Kaharoa Tephra erupted from Mt Tarawera in c. 1314 AD, Rotomahana Mud from the 1886 AD eruption of Mt Tarawera, and thin dustings of andesitic ash from the 1995-1996 AD eruptions of Mt Ruapehu. In the Kaituna and Pongakawa lowlands and around the Maketu and Wai hi estuaries there is a late Pleistocene to Holocene sequence of fluvial terraces, alluvial plains, dune sands, minor loess, estuarine sands and muds, peats, and intercalated tephra layers

News from Academy Bay

Sea Cucumber Fishing Boat Captured. Park Warden Wounded by Bullet in Confrontation Between Illegal Sea Cucumber Fishermen and Patrol Personnel of the Galápagos National Park. Peaceful Demonstration to Reject Violence in Galápagos. Conflict in the Galápagos Biological Reserve for Marine Resources, a Statement by the President of the Charles Darwin Foundation. Rediscovery of an "Extinct" Endemic Plant, the Floreana Flax Linum cratericola. The Arrival of Marek's Disease to Galápagos. Mortality of Giant Tortoises at El Chato, Isla Santa Cruz. The Darwin Station Begins a Monthly Program on Local Television. Account of a Historical Crossing of Isthmus Perry

Abundance and Isotopic Composition of Gases in the Martian Atmosphere: First Results from the Mars Curiosity Rover

Repeated measurements of the composition of the Mars atmosphere from Curiosity Rover yield a (40)Ar/N2 ratio 1.7 times greater and the (40)Ar/(36)Ar ratio 1.6 times smaller than the Viking Lander values in 1976. The unexpected change in (40)Ar/N2 ratio probably results from different instrument characteristics although we cannot yet rule out some unknown atmospheric process. The new (40)Ar/(36)Ar ratio is more aligned with Martian meteoritic values. Besides Ar and N2 the Sample Analysis at Mars instrument suite on the Curiosity Rover has measured the other principal components of the atmosphere and the isotopes. The resulting volume mixing ratios are: CO2 0.960(+/- 0.007); (40)Ar 0.0193(+/- 0.0001); N2 0.0189(+/- 0.0003); O2 1.45(+/- 0.09) x 10(exp -3); and CO 5.45(+/- 3.62) x 10(exp 4); and the isotopes (40)Ar/(36)Ar 1.9(+/- 0.3) x 10(exp 3), and delta (13)C and delta (18)O from CO2 that are both several tens of per mil more positive than the terrestrial averages. Heavy isotope enrichments support the hypothesis of large atmospheric loss. Moreover, the data are consistent with values measured in Martian meteorites, providing additional strong support for a Martian origin for these rocks