Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
3,926
result(s) for
"Herrmann, F"
Sort by:
Age-associated declines in muscle mass, strength, power, and physical performance: impact on fear of falling and quality of life
Summary
This 3-year longitudinal study among older adults showed that declining muscle mass, strength, power, and physical performance are independent contributing factors to increased fear of falling, while declines of muscle mass and physical performance contribute to deterioration of quality of life. Our findings reinforce the importance of preserving muscle health with advancing age.
Introduction
The age-associated loss of skeletal muscle quantity and function are critical determinants of independent physical functioning in later life. Longitudinal studies investigating how decrements in muscle components of sarcopenia impact fear of falling (FoF) and quality of life (QoL) in older adults are lacking.
Methods
Twenty-six healthy older subjects (age, 74.1 ± 3.7; Short Physical Performance Battery (SPPB) score ≥10) and 22 mobility-limited older subjects (age, 77.2 ± 4.4; SPPB score ≤9) underwent evaluations of lower extremity muscle size and composition by computed tomography, strength and power, and physical performance at baseline and after 3-year follow-up. The Falls Efficacy Scale (FES) and Short Form-36 questionnaire (SF-36) were also administered at both timepoints to assess FoF and QoL, respectively.
Results
At 3-year follow-up, muscle cross-sectional area (CSA) (
p
< 0.013) and power decreased (
p
< 0.001), while intermuscular fat infiltration increased (
p
< 0.001). These decrements were accompanied with a longer time to complete 400 m by 22 ± 46 s (
p
< 0.002). Using linear mixed-effects regression models, declines of muscle CSA, strength and power, and SPPB score were associated with increased FES score (
p
< 0.05 for each model). Reduced physical component summary score of SF-36 over follow-up was independently associated with decreased SPPB score (
p
< 0.020), muscle CSA (
p
< 0.046), and increased 400 m walk time (
p
< 0.003).
Conclusions
In older adults with and without mobility limitations, declining muscle mass, strength, power, and physical performance contribute independently to increase FoF, while declines of muscle mass and physical performance contribute to deterioration of QoL. These findings provide further rationale for developing interventions to improve aging muscle health.
Journal Article
Sea star : Sean Scully at the National Gallery
Sean Scully (b.1945) is an Irish-born, American-based painter and printmaker, best known for his monumental oil paintings which draw on the traditions of Abstract Expressionism. This beautiful catalogue showcases a new body of work inspired by the National Gallery's own collection and in particular by British artist J. M. W. Turner's The Evening Star (c. 1830). For Scully, this elegiac picture constitutes one of Turner's most profound paintings, leading to new departures in his own work; using the motif of stripes or checkerboards, the artist evokes landscapes and architecture, horizons, fields, and coastlines, in which his contemplative forms become reminders of personal experiences and distinctive moments. Vast, bold panel paintings with richly textured surfaces are illustrated together with delicate works on paper: aquatints, luminous pastels, and watercolors. The accompanying text includes newly commissioned essays and an interview with the artist, while a photo essay highlights the thick impasto, strong brushstrokes, and vivid colors that distinguish Scully's painting.00Exhibition: National Gallery, London, UK (13.04-11.08.2019).
Book
Ultra-low-power second-order nonlinear optics on a chip
Second-order nonlinear optical processes convert light from one wavelength to another and generate quantum entanglement. Creating chip-scale devices to efficiently control these interactions greatly increases the reach of photonics. Existing silicon-based photonic circuits utilize the third-order optical nonlinearity, but an analogous integrated platform for second-order nonlinear optics remains an outstanding challenge. Here we demonstrate efficient frequency doubling and parametric oscillation with a threshold of tens of micro-watts in an integrated thin-film lithium niobate photonic circuit. We achieve degenerate and non-degenerate operation of the parametric oscillator at room temperature and tune its emission over one terahertz by varying the pump frequency by hundreds of megahertz. Finally, we observe cascaded second-order processes that result in parametric oscillation. These resonant second-order nonlinear circuits will form a crucial part of the emerging nonlinear and quantum photonics platforms.
Here, the authors demonstrate a chip-scale device that realizes a comprehensive set of resonant second order nonlinear processes including optical parametric oscillation with a threshold power of 70 microwatts.
Journal Article
Mirror symmetric on-chip frequency circulation of light
Integrated circulators and isolators are important for developing on-chip optical technologies such as laser cavities, communication systems and quantum information processors. These devices seem to inherently require mirror symmetry breaking to separate backwards from forwards propagation, and thus existing implementations rely on magnetic materials or interactions driven by propagating waves. By contrast to past works, we exhibit a mirror-symmetric non-reciprocal device that comprises three coupled photonic resonators implemented in thin-film lithium niobate. Applying radiofrequency modulation, we drive conversion between the frequency eigenmodes of this system. We measure nearly 40 dB of isolation for approximately 75 mW of radiofrequency power near 1,550 nm. We simultaneously generate non-reciprocal conversion between all of the eigenmodes to demonstrate circulation. Mirror-symmetric circulation simplifies the fabrication and operation of non-reciprocal integrated devices. Finally, we consider applications of such on-chip isolators and circulators, such as full-duplex isolation within a single waveguide.Researchers demonstrate an integrated mirror-symmetric non-reciprocal device enabled by three coupled photonic resonators. Nearly 40 dB of isolation is achieved at telecommunications wavelengths using 75 mW of radiofrequency power.
Journal Article
Low back pain and health-related quality of life in community-dwelling older adults
Purpose
Investigation of self-reported of low back pain (LBP) over the last month and associated health-related quality of life (HRQoL) in a sample of a community-dwelling population aged ≥65.
Methods
Cross-sectional study including older adults selected randomly from population records. Data were collected within a sample stratified by age and sex. Physical and psychological healths were investigated using a standardized definition of LBP and the EuroQoL-5D for HRQoL. Analyses were first conducted on the entire sample (
N
= 3042) and subsequently considering the subsample who reported LBP and a paired sample drawn from the pool of LBP-free respondents.
Results
889 (29 %) respondents reported LBP within the past month, present ‘most days’ or ‘every day’ in 52 % and limiting activities in the same proportion. Average pain score was 4.6 (SD 2.2; 0–10 scale). Age was associated with pain frequency and duration, with younger groups more often reporting pain ‘some days’ and ‘dating back <3 months’. Results of regression analyses showed that individuals suffering from LBP had significantly more problems than LBP non-sufferers on all EQ-5D subscales, except self-care: pain/discomfort (OR 5.33; 95 % CI [4.19–6.79]), mobility (OR 2.66; 95 % CI [2.04–3.46]), usual activities (OR 1.92; 95 % CI [1.42–2.60]), anxiety/depression (OR 1.59; 95 % CI [1.23–2.04]) and self-care (OR 1.29; 95 % CI [0.84–1.98]).
Conclusion
LBP appears to be a more permanent condition in the older groups. LBP may be a part of the definition of a subgroup of elderly at risk of becoming frail in relation with higher levels of functional limitations, psychological difficulties and social restrictions, hence globally impaired HRQoL.
Journal Article
Gait variability at fast-pace walking speed: A biomarker of mild cognitive impairment?
The interpretation of the increase in stride-to-stride variability of stride time (STV) regarding the evolution of cognitive deficits across the dementia spectrum is matter of debate.
The aim of this study was to compare STV at usual and fast-pace walking speeds of MCI patients with that of cognitively healthy individuals (CHI) and Alzheimer's disease (AD) patients with mild dementia, while considering the effects of potential confounders.
STV while walking at usual and fast-pace walking speeds was recorded with the GAITRite® system from 116 older adults (mean age 75.6±6.5 years; 55.2% female) divided into 3 groups according to their cognitive status (44 CHI, 39 MCI patients and 33 AD patients with mild dementia).
The full adjusted multiple linear regression models showed that high STV was associated with slow gait speed at usual-pace walking speed (P=0.002) and with the MCI status at fast-pace walking speed (P=0.015).
High STV at fast-pace walking speed was a specific gait disturbance of MCI patients in the sample of studied participants, and thus could be used in the future as a specific biomarker of MCI patients.
Journal Article
Integrated millimeter-wave cavity electro-optic transduction
Emerging communications and computing technologies will rely ever-more on expanding the useful radio frequency spectrum into the millimeter-wave and terahertz frequency range. Both classical and quantum applications would benefit from advancing integration and incorporation of millimeter-wave and electro-optic technologies into common devices, such as modulators. Here we demonstrate an integrated triply-resonant, superconducting electro-optic transducer. Our design incorporates an on-chip 107 GHz niobium titanium nitride superconducting resonator, modulating a thin-film lithium niobate optical racetrack resonator operating at telecom wavelengths. We observe a maximum photon transduction efficiency of
η
OE
≈ 0.82 × 10
−6
and an average single-photon electro-optic interaction rate of
g
0
/2
π
≈ 0.7 kHz. We also present a study and analysis of the challenges associated with the design of integrated millimeter-wave resonators and propose possible solutions to these challenges. Our work paves the way for further advancements in resonant electro-optic technologies operating at millimeter-wave frequencies.
The authors report an integrated triply-resonant superconducting electro-optic transducer combining a 107 GHz NbTiN resonator with a thin-film lithium niobate optical racetrack at telecom wavelengths. Achieving
η
OE
≈ 0.82 × 10
−6
and
g
0
/2
π
≈ 0.7 kHz, this work analyzes mm-wave resonator design challenges and proposes strategies for improved quantum transduction.
Journal Article
The impact of low back pain on health-related quality of life in old age: results from a survey of a large sample of Swiss elders living in the community
PurposeThe present study aims at investigating the effects of low back pain (LBP), i.e., type of symptoms, activity limitations, frequency, duration, and severity on health-related quality of life (HRQoL) in a sample of 707 community-dwelling men and women aged ≥ 65 years living in Switzerland.MethodsThe study is part of a larger survey conducted in Switzerland on a sample of older adults selected randomly from population records, stratified by age and sex. The Standardized Back Pain Definition was used to investigate LBP, and HRQoL was assessed by means of the EQ-5D, including Health Utility Index (HUI) measures.ResultsFor more than half of the sufferers, pain was chronic, occurred most days or every day and induced activity limitations. One-third of the sufferers reported sciatica symptoms. Individuals reporting every day pain, severe pain and more than 3 years since the last episode without pain lost nearly 10 points of HRQoL. Amongst the dimension of HRQoL, Mobility was the most affected by LBP.ConclusionsThese results provide further insight into the impact of qualitative aspects of LBP and in particular the importance of radiating leg pain and pain frequency and duration. While LBP-related activity limitations had little impact on both self-rated overall health and HUI, radiating leg pain and pain frequency and duration were associated with significantly decreased scores on both dimensions.
Journal Article