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Associations between physical activity and BMI, body fatness, and visceral adiposity in overweight or obese Latino and non-Latino adults.
Background/objectivesAlthough several studies have reported associations between moderate to vigorous physical activity (MVPA), body fatness and visceral adipose tissue (VAT), the extent to which associations differ among Latinos and non-Latinos remains unclear. This study evaluated the associations between body composition and MVPA in Latino and non-Latino adults.Subjects/methodsAn exploratory, cross-sectional analysis was conducted using baseline data collected from 298 overweight adults enrolled in a 12-month randomized controlled trial that tested the efficacy of text messaging to improve weight loss. MVPA, body fatness and VAT were assessed by waist-worn accelerometry, dual-energy x-ray absorptiometry (DXA), and DXA-derived software (GE CoreScan GE, Madison, WI, USA), respectively. Participants with <5 days of accelerometry data or missing DXA data were excluded; 236 participants had complete data. Multivariable linear regression assessed associations between body composition and MVPA per day, defined as time in MVPA, bouts of MVPA (time per bout ⩾10 min), non-bouts of MVPA (time per bout <10 min) and meeting the 150-min MVPA guideline. The modifying influence of ethnicity was modeled with a multiplicative interaction term.ResultsThe interaction between ethnicity and MVPA in predicting percent body fat was significant (P=0.01, 95% confidence interval (CI) (0.58, 4.43)) such that a given increase in MVPA was associated with a greater decline in total body fat in non-Latinos compared with Latinos (adjusted for age, sex and accelerometer wear time). There was no interaction between ethnicity and MVPA in predicting VAT (g) (P=0.78, 95% CI (-205.74, 273.17)) and body mass index (BMI) (P=0.18, 95% CI (-0.49, 2.26)).ConclusionsAn increase in MVPA was associated with a larger decrease in body fat, but neither BMI nor VAT, in non-Latinos compared with Latinos. This suggests that changes in VAT and BMI in response to MVPA may be less influenced by ethnicity than is total body fatness
Evaluation of management strategies for the operation of high-speed railways in China
High-Speed Train (HST) operations have recently been introduced in rail passenger transportation markets worldwide. Although the technologies for such operations have levelled at speeds of around 300 km/h, the operating parameters to be adopted in each application will differ from country to country. The operating environment will be one of the crucial success factors for the implementation of HST operations in China. This paper compares three different management/ownership models which might be used in China. The paper analyzes the characteristics of each model and proposes an optimal plan of an operational system to develop HST operations in China by using a hierarchy goals achievement matrix approach
Synthesis of a Molecular Charm Bracelet via Click Cyclization and Olefin Metathesis Clipping
We describe the synthesis of a polycatenated cyclic polymer, a structure that resembles a
molecular charm bracelet. Ruthenium-catalyzed ring-opening metathesis polymerization of an aminocontaining
cyclic olefin monomer in the presence of a chain transfer agent generated an α,ω-diazide
functionalized polyamine. Cyclization of the resulting linear polyamine using pseudo-high-dilution coppercatalyzed
click cyclization produced a cyclic polymer in 19% yield. The click reaction was then further
employed to remove linear contaminants from the cyclic polymer using azide- and alkyne-functionalized
scavenging resins, and the purified cyclic polymer product was characterized by gel permeation
chromatography, ^1H NMR spectroscopy, and IR spectroscopy. Polymer hydrogenation and conversion to
the corresponding polyammonium species enabled coordination and interlocking of diolefin polyether
fragments around the cyclic polymer backbone using ruthenium-catalyzed ring-closing olefin metathesis to
afford a molecular charm bracelet structure. This charm bracelet complex was characterized by ^1H NMR
spectroscopy, and the catenated nature of the small rings was confirmed using two-dimensional diffusion-ordered
NMR spectroscopy
Blur resolved OCT: full-range interferometric synthetic aperture microscopy through dispersion encoding
We present a computational method for full-range interferometric synthetic
aperture microscopy (ISAM) under dispersion encoding. With this, one can
effectively double the depth range of optical coherence tomography (OCT),
whilst dramatically enhancing the spatial resolution away from the focal plane.
To this end, we propose a model-based iterative reconstruction (MBIR) method,
where ISAM is directly considered in an optimization approach, and we make the
discovery that sparsity promoting regularization effectively recovers the
full-range signal. Within this work, we adopt an optimal nonuniform discrete
fast Fourier transform (NUFFT) implementation of ISAM, which is both fast and
numerically stable throughout iterations. We validate our method with several
complex samples, scanned with a commercial SD-OCT system with no hardware
modification. With this, we both demonstrate full-range ISAM imaging, and
significantly outperform combinations of existing methods.Comment: 17 pages, 7 figures. The images have been compressed for arxiv -
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Power Dependent Lineshape Corrections for Quantitative Spectroscopy
The Voigt profile - a convolution of a Gaussian and a Lorentzian - accurately
describes the absorption lines of atomic and molecular gases at low probe
powers. Fitting such to experimental spectra yields both the Lorentzian natural
linewidth and the Gaussian Doppler broadening. However, as the probe power
increases saturation effects introduce spurious power dependence into the
fitted Doppler width. Using a simple atomic model, we calculate power-dependent
corrections to the Voigt profile, which are parametrized by the Gaussian
Doppler width, the Lorentzian natural linewidth, and the optical depth. We show
numerically and experimentally that including the correction term substantially
reduces the spurious power dependence in the fitted Gaussian width.Comment: 4 pages, 3 figure
Dry Powder Deposition and Compaction for Functionally Graded Ceramics
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65992/1/j.1551-2916.2006.01272.x.pd
Fabrication and Properties of an Anisotropic TiO 2 Dielectric Composite
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65849/1/j.1551-2916.2006.01134.x.pd
A Systemic Framework for Improving Clients\u27 Understanding of Software Requirements
This research proposes a systemic framework for the understanding of client requirements in Information System development that is particularly relevant for project contexts characterized by diversity of stakeholder values and significant complexity. In spite of the strong research tradition associated with Soft Systems Methodology and the growing interest in the Work System Method, the level of use of those by practitioners is not high as such situations require harnessing the strengths of more than one methodology. The paper explores the selection of techniques from three systems methodologies and mixing them to be applied in the process of requirements understanding by clients. The mixing of methods from various methodologies is justified through the principles of Critical Systems Practice and the process of their use is guided by Action Design Research. The contribution of the paper for the field of Information Systems is in the proposal of a more powerful framework for promoting organizational learning about software requirements understanding by clients
Permittivity of Porous Titanate Dielectrics
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65907/1/j.1551-2916.2006.01323.x.pd
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