Postural Sway during Local Vibratory Stimulation for Proprioception in Elderly Individuals with Pre-Sarcopenia

Objective: Many studies have demonstrated that the loss of muscle mass (LMM) poses a risk of postural instability in the elderly; however, few studies have shown how LMM decreases proprioception. In this study, we investigated the changes in postural sway among older individuals with LMM induced by application of a local vibratory stimulus. Method: We enrolled 64 older adults (mean age). Postural sway was measured while applying vibration stimuli of 30, 60, and 240 Hz to both the gastrocnemius and lumbar multifidus muscles. We also measured the relative proprioceptive weighting ratio (RPW) of postural sway. The patients were divided into LMM and non-LMM (NLMM) groups. The study subjects were compared in terms of their age, height, weight, body mass index (BMI), lower leg skeletal muscle mass index (LSMI), L4/5 lumbar multifidus cross-sectional area ratio, and RPW at 30, 60, and 240 Hz. Results: Subjects in the LMM group showed a significantly lower RPW at 60 Hz, LSMI, and BMI than did those in the NLMM group. Conclusions: Decrease in RPW with 60-Hz stimulation concerning the lower leg proprioception is a risk factor for LMM-associated postural instability in the elderly. Consequently, with respect to the gastrocnemius muscles proprioception in LMM, it is necessary to perform assessments using muscle spindle stimuli.     

Preferred Growth Direction of Ni Single Crystals by the Floating-Zone Method

In Ni single crystals grown by the floating-zone method, it was found that their growth directions tended to concentrate towards the 〈111〉 or the 〈100〉 direction. An interpretation was put forward for the preferred direction of these crystals in terms of thermal stability of the crystallographic planes in the solid-liquid interface.     

The synthesis of benzofuroquinolines. I. Some benzofuro[2,3-b]quinoline and benzofuro[3,2-c]quinoline derivatives

Benzofuro[2,3-b]quinoline ( Ia ) and its 11-methyl derivative ( Ib ) were synthesized by demethylcyclization of 3-(o-methoxyphenyl)-1,2-dihydroquinolin-2-ones (VIa,b). Benzofuro[2,3-b]quinoline-11-carboxylic acid (Id) was synthesized by chlorination followed by the action of potassium hydroxide of a lactone (IX) prepared by demethyl-cyclization of 3-(o-methoxyphenyl)-2-oxo-1,2-dihydroquinoline-4-carboxylic acid (VIII). Isomeric benzofuro[3,2-c]quinoline (Ha) and its 6-methyl derivative (IIb) were synthesized by demethyl-cyclization of 3-(o-methoxyphenyl)-1,4-dihydroquinolin-4-ones (XIa,b). Both the methyl derivatives (Ib and IIb) were converted to the carboxylic acids (Id and IId) through condensation with benzaldehyde followed by oxidation. The benzofuroquinolines (Ia,b,d and IIa,b) thus obtained were oxidized to the corresponding N-oxides (IIIa,b,d and IVa,b).     

Extraction protocol and mass spectrometry method for quantification of doxorubicin released locally from prodrugs in tumor tissue

The localized conversion of inactive doxorubicin prodrug chemotherapeutics to pharmacalogically active forms is difficult to quantify in mouse tumor models because it occurs only in small regions of tissue. The tumor tissue extraction protocol and LC–MS/MS analysis method described here were optimized to obtain a detection limit of 7.8 pg for the activated doxorubicin and 0.36 ng for the doxorubicin prodrug. This method can be useful for determining the biodistribution and activation efficiency for many different doxorubicin prodrugs. It can also be used for quantification of doxorubicin from tumor models that have poor vascularization resulting in low tissue accumulation. Copyright © 2013 John Wiley & Sons, Ltd.     

Detection of the frustrated rotation mode of CO on Cu(0 0 1) by very low energy photoelectron spectroscopy

We have measured the very low energy photoelectron spectra of the clean and CO covered Cu(0 0 1) surfaces at low temperature (15 K). A step at 34.5 meV below the Fermi level appeared in the CO/Cu(0 0 1) spectra, while no structure was found at the same position in the clean Cu(0 0 1) spectrum. Furthermore, we have succeeded in measuring the spectral shift of the step to 33.2 meV below the Fermi level by isotopic substitution of the CO molecule. We have concluded that this step originates from the inelastic scattering of photoelectrons through excitation of the frustrated rotation mode of the CO molecule.     

Normal theory likelihood ratio statistic for mean and covariance structure analysis under alternative hypotheses

The normal distribution based likelihood ratio (LR) statistic is widely used in structural equation modeling. Under a sequence of local alternative hypotheses, this statistic has been shown to asymptotically follow a noncentral chi-square distribution. In practice, the population mean vector and covariance matrix as well as the model and sample size are always fixed. It is hard to justify the validity of the noncentral chi-square distribution for the resulting LR statistic even when data are normally distributed and sample size is large. By extending results in the literature, this paper develops normal distributions to describe the behavior of the LR statistic for mean and covariance structure analysis. A sequence of local alternative hypotheses is not necessary for the proposed distributions to be asymptotically valid. When the effect size is medium and above or when the model is not trivially misspecified, empirical results indicate that a refined normal distribution describes the behavior of the LR statistic better than the commonly used noncentral chi-square distribution, as measured by the Kolmogorov-Smirnov distance. Quantile-quantile plots are also provided to better understand the different distributions.     

Water‐proton relaxivity of hyperbranched polymers carrying TEMPO radicals

High water‐soluble hyperbranched poly(styrene) (HPS) polymers carrying stable 2, 2, 6, 6‐tetramethylpiperidine‐1‐oxyl (TEMPO) radicals, HPS‐N‐TEMPO, HPS‐Im‐TEMPO, and HPS‐Im‐(TEMPO)₂, were prepared in ca. 60% introducing yield. HPS‐N‐TEMPO and HPS‐Im‐TEMPO were determined to be nearly spherical shapes of the diameter of 2.4 ± 0.6 and 2.2 ± 0.6 nm, respectively, by transmission electron microscope (TEM) images. The values of water‐proton relaxivity, r₁, at 25 MHz, 0.59 T, and 25 °C were 6.0, 5.2, and 14 mM^?1 sec^?1 for HPS‐N‐TEMPO, HPS‐Im‐TEMPO, and HPS‐Im‐(TEMPO)₂, respectively. The spin‐lattice relaxation time (T₁)‐weighted images in phantom were also observed. Copyright © 2009 John Wiley & Sons, Ltd.     

Response of circular plates to thermal impact

The thermally induced vibrations of simply supported circular plates are investigated analytically. The solution is composed of two parts; the first is obtained by neglecting the inertia term and the second represents the vibrating component which oscillates about the first, due to the effect of the inertia. One of the reasons for separating the solution in two parts is to obtain the complete solution expediently. But when this is represented in non-dimensional form, the quasi-static part has the particular desirable feature that it is independent of the strength of the thermal shock and thus will give an index for the displacement due to the temperature moment if (and only if) the inertia force has a small effect. The basic equation is governed by only one non-dimensional parameter B which contains the density, the thermal diffusivity of the material and the radius of the plate in its numerator, and the flexural rigidity and thickness of the plate in its denominator, all to various powers. B represents the strength of the thermal shock. As B increases the non-dimensional amplitude of the vibration becomes large and the natural frequency decreases.