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Multiple sclerosis (MS) is a debilitating neurological disease associated with a variety of psychological, cognitive, and motoric symptoms. Walking is among the most important functions compromised by MS. Dual-task walking (DTW), an everyday activity in which people walk and engage in a concurrent, discrete task, has been assessed in MS, but little is known about how it relates to other MS symptoms. Self-awareness theory suggests that DTW may be a function of the interactions among psychological, cognitive, and motor processes.
Method:
Cognitive testing, self-report assessments for depression and falls self-efficacy (FSE), and walk evaluations [DTW and single-task walk (STW)] were assessed in seventy-three people with MS in a clinical care setting. Specifically, we assessed whether psychological factors (depression and FSE) that alter subjective evaluations regarding one’s abilities would moderate the relationships between physical and cognitive abilities and DTW performance.
Results:
DTW speed is related to diverse physical and cognitive predictors. In support of self-awareness theory, FSE moderated the relationship between STW and DTW speeds such that lower FSE attenuated the strength of the relationship between them. DTW costs – the change in speed normalized by STW speed – did not relate to cognitive and motor predictors. DTW costs did relate to depressive symptoms, and depressive symptoms moderated the effect of information processing on DTW costs.
Conclusions:
Findings indicate that an interplay of physical ability and psychological factors – like depression and FSE – may enhance understanding of walking performance under complex, real-world, DTW contexts.
Lake Johnston cirque contains some of the best subalpine rainforest in Tasmania. Pollen from the sediments shows Lagarostrobos franklinii, which presently reaches 1040 m, may be a glacial relict. Nothofagus cunninghamii–Nothofagus gunnii subalpine rainforest developed between 9000 and 6000 14C yr B.P., with a maximum at 8700 14C yr B.P. After 6000 14C yr B.P. Nothofagus gunnii became more important, and from 3600 14C yr B.P. sclerophyll and heath components increased. Partial burning of the catchment occurred periodically. Early Holocene climate was warmer and wetter than late Holocene climate. The vegetation and climate changes are similar to those recorded from western South Island New Zealand and Chile. Radiocarbon dates give a sedimentation rate of 0.43 mm/yr. Cores are correlated by magnetic susceptibility. Magnetic ages are assigned by matching with the 14C-dated secular variation master curve for southeastern Australia. Magnetic ages are consistent with the 14C chronology when the former are adjusted by 350 years.
The ethical principle of autonomy requires physicians to respect patient autonomy when present, and to protect the patient who lacks autonomy. Fulfilling this ethical obligation when a patient has a communication impairment presents considerable challenges. Standard methods for evaluating decision-making capacity require a semistructured interview. Some patients with communication impairments are unable to engage in a semistructured interview and are at risk of the wrongful loss of autonomy. In this article, we present a general strategy for assessing decision-making capacity in patients with communication impairments. We derive this strategy by reflecting on a particular case. The strategy involves three steps: (1) determining the reliability of communication, (2) widening the bandwidth of communication, and (3) using compensatory measures of decision-making capacity. We argue that this strategy may be useful for assessing decision-making capacity and preserving autonomy in some patients with communication impairments.
Beaches and dunes of the open coast form one of the globe’s longest ecological interfaces, linking the oceans with the land. These systems are of great importance to society as prime sites for housing and recreation, buffers against storms, and providers of fisheries and mineral resources. By contrast, their unique ecological attributes and biodiversity are much less recognized. In this chapter, we provide a synthesis of the key ecological features and functions of beaches and dunes, outline the main elements of their faunal biodiversity, examine human threats and their biological consequences, and sketch some salient issues in management to achieve conservation of these unique ecosystems. It is apparent that the range of ecosystem goods and services is broad, but nutrient cycling, water filtration, and the provision of habitat and prey for a diverse range of animals are often the key ecological traits. Contrary to common perceptions, beaches and dunes contain a diverse and unique set of species, many of which are found nowhere else. In addition to the complement of highly adapted invertebrates, many wildlife species (e.g. birds, turtles, fishes) are dependent on beaches and dunes for nesting and feeding, and they use these habitats extensively. Human pressures on sandy shorelines and their biodiversity are numerous. Coastal squeeze is, however, the most pervasive, trapping beaches and their biota between the pressures of development from the terrestrial side and the consequences of climate change from the marine side. Beaches are also naturally malleable habitats whose interlinkages, including the exchange of organisms, with the abutting dunes and surf zones are essential to their functioning. Unfortunately, human actions intended to arrest the dynamics of beach habitats, such as seawalls and dune stabilizations, run counter to these natural dynamics and generally produce negative environmental outcomes. These present a set of formidable management challenges when the primary goal is to conserve intact ecosystems and biodiversity, calling for more systematic approaches in conservation design and implementation for beach and dune ecosystems.
To demonstrate that nosocomial transmission of vancomycin-resistant enterococci (VRE) can be terminated and endemicity prevented despite widespread dissemination of an epidemic strain in a large tertiary-care referral hospital.
Interventions:
Two months after the index case was detected in the intensive care unit, 68 patients became either infected or colonized with an epidemic strain of vanB vancomycin-resistant Enterococcus faecium despite standard infection control procedures. The following additional interventions were then introduced to control the outbreak: (1) formation of a VRE executive group; (2) rapid laboratory identification (30 to 48 hours) using culture and polymerase chain reaction detection of vanA and vanB resistance genes; (3) mass screening of all hospitalized patients with isolation of carriers and cohorting of contacts; (4) environmental screening and increased cleaning; (5) electronic flagging of medical records of contacts; and (6) antibiotic restrictions (third-generation cephalosporins and vancomycin).
Results:
A total of 19,658 patient and 24,396 environmental swabs were processed between July and December 2001. One hundred sixty-nine patients in 23 wards were colonized with a single strain of vanB vancomycin-resistant E. faecium. Introducing additional control measures rapidly brought the outbreak under control. Hospital-wide screening found 39 previously unidentified colonized patients, with only 7 more nonsegregat-ed patients being detected in the next 2 months. The outbreak was terminated within 3 months at a cost of $2.7 million (Australian dollars).
Conclusion:
Despite widespread dissemination of VRE in a large acute care facility, eradication was achievable by a well-resourced, coordinated, multifaceted approach and was in accordance with good clinical governance.
Material and electrical characterization of n-type and p-type Si1-x-yGex Cy epitaxial layers on Si(100) was performed using silicided platinum Schottky contacts. XRD studies show Pt silcidation of SiGeC proceeds from non-reacted Pt to Pt2(SiGeC) and completes with the Pt(SiGeC) phase similar to Pt/Si silicides, but Pt silicide reactions with SiGeC are shown to require higher temperatures than Pt reactions with Si. Electrical characterization of Pt(SiGeC) contacts to n-type Sil1-x-yGexCx/Si shows rectifying behavior with constant barrier heights of 0.67eV independent of composition, indicating Fermi level pinning relative to the SiGeC conduction band is occurring. Pt(SiGeC) contacts to p-type Si1-x-yGexCy/Si are also rectifying with barrier heights that track the variation of the SiGeC energy bandgap.
We present optical photometry of the eclipsing supersoft source, CAL 87. We find the eclipse structure to be stable over ~ 4 y, derive an improved ephemeris of To = HJD 2450111.5144(3)+0.442674(7)E, and see new structure in the light curve morphology.
B – V and R – I color maps (from CCD imagery obtained at Cerro Tololo Inter-American Observatory) of six barred spiral galaxies have been used (Horst 1992) to investigate stellar populations within the bars and nuclei. Two-color diagrams show that the distribution of pixel colors largely parallels the expected locus for normal unreddened stars. If the “reddening” law is assumed to remain fairly constant, and if the slope of the vector associated with this reddening law is additionally assumed to be commensurate with that derived from models which take into account both absorption and scattering (Witt et al. 1992), one concludes that the overall effects of internal extinction are remarkably uniform along the bars and within the nuclei of all six galaxies. It thus appears reasonable as a first approximation to shift the observed data along the assumed reddening vector to estimate the spectral types of stars that are present and to investigate differences between bar and bulge populations. Nevertheless, to correct surface brightness distributions for the effects of internal extinction, and hence to proceed with more detailed attempts to model the various luminosity components (i. e., the bulge, bar, etc.), is a complex problem which must be addressed through numerical models explicitly designed to reproduced barred systems.
Afield study was conducted between 1972 and 1982 to compare the effects of previous crop on row crop yields under rainfed conditions in eastern Nebraska. The objectives were to determine the effects of fallow and three previous crops: corn (Lea. maysLJ, soybeans /Glycine max (L.) Mem], and grain sorghum /Sorghum bicolor (L.) Moench], on the growth and grain yield of the same crops. The study was conducted on a Sharpsburg silty clay loam (fine, montmorillonitic, mesicf Typic Argiudoll). Corn grain yield was most variable (C. V. 23.4percent) compared to soybean (C. V. 13.6percent) or grain sorghum (C. V. 9.5 percent) yields. Corn was also the most sensitive crop to previous crop effects. The range of treatment yields for each crop was 47 percent, 22 percent, and 11 percent of the overall means for corn, soybean, and sorghum, respectively. Previous crop affected yields for all crops, but the effects were not consistent across years. All crops produced highest yield following fallow. Yields of corn, soybean, and grain sorghum following fallow were 74, 25, and 10 percent higher than their respective monoculture yields. In years of average precipitation, a corn-soybean sequence produced the greatest yield. In years having above- or below-normal precipitation, a grain sorghum-soybean sequence produced the highest yield.
The Laws Observatory of the University of Missouri is an example of the small university observatory that under lean financial circumstances succeeded for a number of years (1890-1920) as a successful research institution. Productive research appears to have been due to the temperament of the individual astronomers who had the ability to find projects which could be accomplished with small telescopes, minimal equipment, and few other resources. In these circumstances, a handful of students began careers in astronomy at the University of Missouri.
We have made an analysis of the visual photometric data contained in the Catalogue of Concentric Aperture UBVRI Photoelectric Photometry of Globular Clusters (Peterson 1986). Structural parameters have been obtained by use of the Simplex algorithm of Caceci and Cacheris (1984) to fit the model curves of King (1966) to the run of cluster luminosity with radius. We find that concentric aperture photometry alone can be used to determine globular cluster core radii and central surface brigtnesses reliably. Application of this techique, however, is limited to about two-thirds of the known clusters of the Galaxy because no or inadequate numbers of photometric measurements exist for the remaining clusters. Accurate determination of cluster concentration classes still requires use of other types of data, such as star counts.
Globular clusters are among the most difficult types of objects to observe with standard photoelectric techniques. Among factors which may contribute to measurement error are the centering of apertures in the oftentimes diffuse cores of clusters, the random distribution of bright stars near the cluster centers, and the determination of an adequate sky correction in fields badly crowded by foreground stars. These problems have been well-discussed by a number of authors (see, e.g., Hanes and Brodie 1984, and the references they cite).