32 research outputs found

    Unusual high-redshift radio broad absorption-line quasar 1624+3758

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    We present observations of the most radio-luminous broad absorption-line (BAL) quasar known, 1624+3758, at redshift z= 3.377. The quasar has several unusual properties. (1) The Fe II UV191 1787-Å emission line is very prominent. (2) The BAL trough (BALnicity index 2990 km s−1) is detached by 21 000 km s−1 and extends to velocity v=−29 000 km s−1. There are additional intrinsic absorbers at −1900 and −2800 km s−1. (3) The radio rotation measure of the quasar, 18 350 rad m−2, is the second highest known. The radio luminosity is P1.4 GHz= 4.3 × 1027 W Hz−1 (H0= 50 km s−1 Mpc−1, q0= 0.5) and the radio loudness is R*= 260. The radio source is compact and the radio spectrum is GHz-peaked, consistent with it being relatively young. The width of the C IV emission line, in conjunction with the total optical luminosity, implies a black hole mass MBH∼ 109 M⊙, L/LEddington≈ 2. The high Eddington ratio and the radio-loudness place this quasar in one corner of Boroson's two-component scheme for the classification of active galactic nuclei, implying a very high accretion rate, and this may account for some of the unusual observed properties. The v=−1900 km s−1 absorber is a possible Lyman-limit system, with N(H I) = 4 × 1018 cm−2, and a covering factor of 0.7. A complex mini-BAL absorber at v=−2200 to −3400 km s−1 is detected in each of C IV, N V and O VI. The blue and red components of the C IV doublet happen to be unblended, allowing both the covering factor and optical depth to be determined as a function of velocity. Variation of the covering factor with velocity dominates the form of the mini-BAL, with the absorption being saturated (e−τ≈ 0) over most of the velocity range. The velocity dependence of the covering factor and the large velocity width imply that the mini-BAL is intrinsic to the quasar. There is some evidence of line-locking between velocity components in the C IV mini-BAL, suggesting that radiation pressure plays a role in accelerating the outflow

    Perceived Benefits of Using Nonpharmacological Interventions in Older Adults With Alzheimer\u27s Disease or Dementia With Lewy Bodies

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    The current qualitative research explored perceived effects of three nonpharmacological interventions (chair yoga [CY], participatory music intervention [MI], and chair-based exercise [CBE]) in managing symptoms in older adults with Alzheimer\u27s disease or dementia with Lewy bodies from family caregivers\u27 perspectives. Three focus groups were conducted following completion of the 12-week interventions. Constant comparative analysis determined whether each intervention had perceived effects on symptoms, based on caregivers\u27 perspectives. Three major themes emerged: (a) Changes in Cognitive Symptoms, (b) Changes in Physical Function, and (c) Changes in Mood, Behavioral Symptoms, and Sleep Disturbance. Results can be integrated into treatment plans for older adults with dementia. Future research should focus on CY or CBE with support from caregivers to manage dementia symptoms and compare CY or CBE practiced with caregivers against CBE or CY practiced solely by participants with dementia. [Journal of Gerontological Nursing, 46(1), 37-46.]

    Sex-specific differences in gait patterns of healthy older adults: Results from the Baltimore Longitudinal Study of Aging

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    The effects of normal aging and orthopedic conditions on gait patterns during customary walking have been extensively investigated. Empirical evidence supports the notion that sex differences exist in the gait patterns of young adults but it is unclear as to whether sex differences exist in older adults. The aim of this study was to investigate sex-specific differences in gait among older adults. Study participants were 336 adults (50-96 years; 162 women) enrolled in the Baltimore Longitudinal Study of Aging (BLSA) who completed walking tasks at self-selected speed without assistance. After adjusting for significant covariates, women walked with higher cadence (p=0.01) and shorter stride length (p=0.006) compared to men, while gait speed was not significantly related to sex. Women also had less hip range of motion (ROM: p=0.004) and greater ankle ROM (p<0.001) in the sagittal-plane, and greater hip ROM (p=0.004) in the frontal-plane. Hip absorptive mechanical work expenditure (MWE) of the women was greater in the sagittal-plane (p<0.001) and lower in the frontal-plane (p<0.001), compared to men. In summary, women's gait is characterized by greater ankle ROM than men while men tend to have greater hip ROM than women. Characterizing unique gait patterns of women and men with aging may be beneficial for detecting the early stages of gait abnormalities that may lead to pathology. (C) 2011 Elsevier Ltd. All rights reserved

    Intention to Screen for Alzheimer’s Disease by Residential Locale

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    A random digit dialing sample from Missouri (USA) was used to compare associations between psychosocial factors and Alzheimer&rsquo;s disease (AD) screening intention based on residential locale. Linear regression associations between demographics and five psychosocial constructs (dementia knowledge, perceived screening benefits, preventive health behaviors, perceived susceptibility, and self-efficacy) and screening intention were compared by residential locale. Participants (n = 932) had a mean age of 62 years (urban: n = 375; suburban: n = 319, rural: n = 238). African Americans more often lived in urban than suburban/rural neighborhoods, and more urban than suburban/rural residents reported insufficient income. Preventative health behaviors (e.g., dentist visits) were higher in urban and suburban versus rural participants. AD screening intention did not differ by residential locale. Among urban participants, self-efficacy to get screened was associated with screening intention. Among rural participants, dementia knowledge was associated with screening intention. Perceived screening benefits and perceived susceptibility to AD were associated with screening intention regardless of locale. Unlike urban participants, rural participants demonstrated greater screening intention with greater dementia knowledge. Our findings suggest that psychosocial factors associated with AD screening intention differ depending on residential locale. Strategies to increase dementia screening may need to account for regional variations to be maximally effective

    Sex-specific differences in gait patterns of healthy older adults: Results from the Baltimore Longitudinal Study of Aging

    No full text
    The effects of normal aging and orthopedic conditions on gait patterns during customary walking have been extensively investigated. Empirical evidence supports the notion that sex differences exist in the gait patterns of young adults but it is unclear as to whether sex differences exist in older adults. The aim of this study was to investigate sex-specific differences in gait among older adults. Study participants were 336 adults (50 – 96 years; 162 women) enrolled in the Baltimore Longitudinal Study of Aging (BLSA) who completed walking tasks at self-selected speed without assistance. After adjusting for significant covariates, women walked with higher cadence (p = 0.01) and shorter stride length (p = 0.006) compared to men, while gait speed was not significantly related to sex. Women also had less hip range of motion (ROM; p = 0.004) and greater ankle ROM (p < 0.001) in the sagittal-plane, and greater hip ROM (p = 0.004) in the frontal-plane. Hip absorptive mechanical work expenditure (MWE) of the women was greater in the sagittal-plane (p < 0.001) and lower in the frontal-plane (p < 0.001), compared to men. In summary, women’s gait is characterized by greater ankle ROM than men while men tend to have greater hip ROM than women. Characterizing unique gait patterns of women and men with aging may be beneficial for detecting the early stages of gait abnormalities that may lead to pathology
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