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Objectives Sleep disorders (SDs), particularly problems with falling asleep or daytime sleepiness, have negative impact on health and longevity. Sleep deprivation is also associated with a decline in physical functioning (PF) that mediates the ability to perform activities of daily living. But it remains unknown if deterioration in PF can predict the risk of having a SD. Therefore, the purpose of the present study is to assess the risk of SD associated with PF status in the US adult population. Study design Cross-sectional study design with data from the National Health and Nutrition Examination Survey from year 2005 to year 2014. Methods PF limitation is assessed by reported difficulty in performing 10 tasks selected from PF questionnaire. SD is identified by subjective description of presence of doctor diagnosed SD. Also, five categories of comorbidities that caused difficulty in carrying out these tasks were created. Results The adults with self-reported PF limitation have 41% higher odds of having a SD (odds ratio [OR] = 1.41, 95% confidence interval [CI] = 1.22–1.59). Moreover, participants having cognitive problems and cardiovascular and pulmonary disorders as secondary conditions that cause difficulty in PF have 145% and 28% higher odds (OR = 2.45 and 1.28; 95% CI = 2.01–3.01 and 1.08–1.53, respectively) of having a SD. Also, females have a 27% lower odds of having a SD than males (OR = 0.73, 95% CI = 0.63–0.83). Conclusion Risk for SD is associated with increasing level of functional disability. We advocate the importance of engagement in physical activities to prevent or delay the onset of SD. [ABSTRACT FROM AUTHOR]

Presents a letter responding to comments on the articles "Simultaneous Measurement of Soil Penetration Resistance and Water Content with a Combined Penetrometer-TDR Moisture Probe" and "A Dynamic Cone Penetrometer for Measuring Soil Penetration Resistance."

The relative abundance of ant species was measured by pit-fall trapping at 44 sites in southern New Mexico and southeastern Arizona, U.S.A.. Sites were selected for study based on documentation of a historyof disturbance or protection from disturbance, exposure to varying intensities of livestock grazing, dominance by an exotic species of plant and vegetation change resulting from disturbance or restoration efforts. Ant community composition, relative abundances of species, and species richness were the same on disturbed and undisturbed sites. None of the metrics based on hypothesized responses of ants to disturbance clearly distinguished between disturbed and undisturbed sites. Ant communities on sites where restoration efforts have resulted in distinct differences in vegetative cover and composition were similar to the ant communities on degraded unrehabilitated sites on the same soil type. Ant communities in riparian cottonwood gallery forests in Arizona and New Mexico were similar but differed from the assemblagesin exotic salt cedar and native ash riparian woodlands. Ant species exhibited remarkable resistance to human-induced disturbances in these rangeland areas. In grasslands dominated by the South African grass, Eragrostis lehmanniana Nees, large seed harvesting ants, Pogonomyrmex spp., were greatly reduced in abundance compared to native grasslands. Other ant metrics were not different in E. lehmanniana grasslands and native grasslands. We conclude that ants cannot be used as indicators of exposure to stress, ecosystem health or of rehabilitation success on rangeland ecosystems. Ants are also not useful indicators of faunal biodiversity in rangeland ecosystems. [ABSTRACT FROM AUTHOR]

We studied indicators of rangeland health on benchmark sites with long, well documented records of protection from stress by domestic livestock or histories of environmental stress and vegetation change. Wemeasured ecosystem properties (metrics) that were clearly linked to ecosystem processes We focused on conservation of soil and water as key processes in healthy ecosystems, and on maintenance of biodiversity and productivity as important functions of healthy ecosystems. Measurements from which indicators of rangeland health were derived included: sizes of unvegetated patches, cover and species composition of perennial grasses, cover and species composition of shrubs and herbaceous perennials, soil slaking, and abundance and species composition of the bird fauna. Indicators that provided an interpretable range of values over the gradient from irreversibly degraded sites to healthy sites included: bare patch index, cover of long-lived grasses, palatability index, and weighted soil surface stability index. Indicators for which values above a threshold may serve as an indicator of rangeland health include: cover of plant species toxic to livestock, cover of exotic species, and cover of increaser species. Several other indicator metrics were judged not sensitive nor interpretable. Examples of application of rangeland health indicators to evaluate the success of various restoration efforts supported the contention that a suite of indicators are required to assess rangeland health. Bird species diversity and ant species diversity were not related to the status of the sample site and were judged inadequate as indicators of maintenance of biodiversity. [ABSTRACT FROM AUTHOR]

Presents a study which determined the applicability of combined use-dependent information and use-invariant soil survey database to evaluate soil quality in the United States. Limitations of soil survey databases; Methodology; Results and discussion.

To measure and manage for C sequestration in heterogeneous rangeland systems, we need to more fully understand spatial patterns of soil resources. Spatial distributions of aggregate stability and soil carbon were investigated in a semiarid rangeland in New Mexico, USA. Soil was analyzed from plant interspaces, black grama (Bouteloua eriopoda (Torr.) Torr.), and mesquite (Prosopis glandulosa Torr.) in a landscape-replicated study. Aggregate stability at the 250 microm scale, carbonate C, organic C and N, C:N ratio, and glomalin, were all highest under mesquite. Soil C:N ratio was the best predictor of aggregate stability. Estimates of metric tons of C per hectare in the top 10 cm were highly variable at patch and landscape scales, varying from 4.2 to 10.5 under mesquite and from 3.0 to 7.0 in interspaces. High variability of aggregate stability and soil C has important implications for C sequestration. We argue that this multi-scale soil heterogeneity must be considered when measuring and managing for C sequestration.

The USA has about 336 Mha of grazing lands of which rangelands account for 48%. Changes in rangeland soil C can occur in response to a wide range of management and environmental factors. Grazing, fire, and fertilization have been shown to affect soil C storage in rangelands, as has converting marginal croplands into grasslands. Carbon losses due to soil erosion can influence soil C storage on rangelands both by reducing soil productivity in source areas and potentially increasing it in depositional areas, and by redistributing the C to areas where soil organic matter mineralization rates are different. Proper grazing management has been estimated to increase soil C storage on US rangelands from 0.1 to 0.3 Mg C ha(-1)year(-1) and new grasslands have been shown to store as much as 0.6 Mg C ha(-1)year(-1). Grazing lands are estimated to contain 10-30% of the world's soil organic carbon. Given the size of the C pool in grazing lands we need to better understand the current and potential effects of management on soil C storage.