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Sarcopenic obesity (SO) increases the risk of mortality more than sarcopenia or obesity alone. Sarcopenia weakens the peripheral and respiratory muscles, leading to respiratory complications. It also induces mitochondrial dysfunction in the peripheral muscle; however, whether mitochondrial dysfunction in respiratory muscles differs among individuals with obesity, sarcopenia, and SO remains unknown. We evaluated the deterioration of respiratory muscle strength and mitochondrial function among normal, sarcopenia, obesity, and SO subjects. Twenty-five patients who underwent lung resections were enrolled between April 2017 and January 2021, and their intercostal muscles were harvested. Based on their L3 muscle index and visceral fat area, the patients were divided into four groups (normal, obesity, sarcopenia, and SO). The clinical data, mRNA expression, and protein expressions associated with mitochondrial biogenesis/fusion/fission in the intercostal muscles were compared among the four groups. The respiratory muscle strength was evaluated using peak expiratory flow rate (PEFR). The PEFR values of the four groups were not significantly different. The levels of pAkt/Akt and mTOR (a marker of protein synthesis) were not significantly different among the four groups; however, those in the SO group were substantially lower than those in the sarcopenia or obesity groups. The levels of Atrogen-1 and MuRF1 (a marker of protein degradation) were not significantly different among the four groups; however, those in the SO group were substantially higher than those in the sarcopenia or obesity groups. Expression of PGC1-α (a marker of mitochondrial biogenesis) in the SO group was significantly lower than that in the normal group. MFN1 and MFN2 (marker of mitochondrial fusion) levels were significantly lower in the SO group than those in the normal group. DRP1 (a marker of mitochondrial fission) level in the SO group was substantially lower than that in the normal group. The expression of TNF-α (a pro-inflammatory cytokine) in the SO group was substantially lower than that in the normal group. Our results suggest that the deterioration of protein synthesis and degradation of mitochondrial function in the respiratory muscles was most prominent in the SO before the weakening of the respiratory muscles. The deterioration mechanism may differentially regulate obesity, sarcopenia, and SO. [ABSTRACT FROM AUTHOR]

This study investigates the concentration effect of chitosan on the formation of iron oxide composites and their electrochemical performance as anode materials in Li–ion batteries. The molecular bridging effect of chitosan chains induces the clustered aggregation of citrate–capped Fe 3 O 4 (C–Fe 3 O 4 ) through the electrostatic interactions between carboxylate groups of C–Fe 3 O 4 and amine groups of chitosan. The thermal calcination of chitosan–linked Fe 3 O 4 leads to carbon–coated Fe 2 O 3 (Fe 2 O 3 @carbon) with the mesopore range of porosity (20–30 nm). The mesoporous Fe 2 O 3 @carbon exhibits an improved electrochemical performance as anode materials in Li–ion batteries. The capacity retention of Fe 2 O 3 @carbon is twice that of bare Fe 2 O 3 after the 50th cycle at 0.1 C. During the charge–discharge process, the Fe 2 O 3 @carbon (3 ml of chitosan) exhibits the highest retention capacity among as–prepared samples, whereas Fe 2 O 3 @carbon (1 ml of chitosan) exhibits the lowest retention capacity owing to the weakly cross–linked iron oxides. The improved performance of Fe 2 O 3 @carbon as anode materials is mainly attributed to the optimal cross–linking effect and structural integrity of mesoporous composite which is beneficial for the effective transport of electrolytes and/or Li–ons, suggesting a useful guideline for preparing porous electrode materials using metal oxide particles. [ABSTRACT FROM AUTHOR]

One of the most important factors influencing the performance of wire-guided missiles is the ability to exchange information through a connected cable. Some of the problems that occur during the process of unwinding the cable from the spool package are tangling of the cable because of low tensile force at the guide-eyelet point and cutting of the cable because of high tensile force. Therefore, it is important to analyze the transient motion of the unwinding cable withdrawn from the spool package, while considering the effect of flexural rigidity on the cable. The unwinding system is defined with cylindrical coordinates, and Hamilton׳s principle in an open system is introduced to represent the mass change of the cable in the control volume. Using Hamilton׳s principle, which takes into consideration the Lagrangian, virtual work, and virtual momentum transport, the unwinding equation with high non-linearity can be derived using boundary conditions. Further, by assuming inextensibility, the tensile force can be derived for the spatial variable. To solve the unwinding equation numerically, Newmark implicit integration is utilized with the central finite-difference approximation for spatial variables. The motions of the cable can be ascertained on the basis of various initial tensile forces by considering the constant unwinding velocity at the guide-eyelet point in air and water. It can be concluded from these motions that fluid resistance is the dominant force on the cable when it is unwound in the water, and, in contrast, centrifugal force is dominant in the air. Further, it can be observed that the initial tensile force required when the cable is unwound in water is greater than that required in air, to avoid unwinding problems such as tangling and cutting of the cable. [ABSTRACT FROM AUTHOR]

Abstract: The capacity variation observed with a carbon-coated silicon monoxide (C-SiO) composite electrode has been explained by the microstructural changes evolved during cycling. In an initial few cycles, the Si domain in SiO is lithiated by alloying reaction, during which cracks form in the Si domain due to volume change. An increase in the contact area between Si and electrolyte solution due to the crack formation, and down-sizing of Si particles facilitate the lithiation reaction, such that the Si domain is lithiated to the most lithium-rich Li–Si phase (Li15Si4). Due to an increase in the degree of lithiation, the reversible capacity steadily increases. A severe volume change that is accompanied by the full lithiation, however, leads to a serious particle crack and pulverization, and surface film deposition on the newly exposed Si surface. All these features lead to a breakdown of electrically conductive network within the electrode layer. As a result, some Si particles are electrically isolated to cause a loss in the reversible capacity. [Copyright &y& Elsevier]

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A small-capacity linear cutting machine (LCM) and a new force measurement method with 1-D load cells were introduced to assess the rock-cutting performance of a low-cost pick cutter. Finite element analysis and LCM tests were implemented to verify the structural stability of the small-capacity LCM and the feasibility of the new force-measurement method. The results of the finite element analysis and the LCM test show that the small-capacity LCM is structurally stable while the new force measurement method is capable of acquiring the cutting forces with an average accuracy of 96.74%. In addition, the small-capacity LCM system for a Roadheader pick cutter was established at a cost of less than 10% of that of a conventional LCM system for a TBM disc cutter. [ABSTRACT FROM AUTHOR]

Abstract: Highly crystalline single phase spherical and monodisperse cobalt ferrite (CoFe2O4) nanoparticles (NPs) with uniform shape and size distribution have been synthesized by one pot-rapid sonochemical method. The effect of different solvents, such as aqueous, alcoholic, and a mix of water/ethanol in 1:1 volume ratio on the shape, size, and crystalline structure of CoFe2O4 NPs were studied using X-ray diffraction, transmission electron microscopy, energy dispersive spectroscopy and Fourier transform infrared spectroscopy. The size of CoFe2O4 nanoparticle was controlled in the range from 20 to 110nm based on the solvent medium used in the synthesis process. Furthermore, the evolution from spherical to cubic morphology of cobalt ferrite NPs is achieved by simply changing the solvent medium from aqueous to alcoholic medium. The magnetic properties of all the synthesized CoFe2O4 NPs were studied by vibrating sample magnetometer (VSM) at room temperature. The magnetization value was found to be particle size dependent, and high magnetization (Ms) of 92.5emu/g was obtained for the CoFe2O4 NPs sample synthesized in a mixed solution of water and ethanol. A possible reaction mechanism for the formation of cobalt ferrite NPs by the sonochemical technique was discussed. The facile method adopted in our study appears to be a promising route for synthesis of highly crystalline nanoparticles within short times and without the need for using any calcination process. [Copyright &y& Elsevier]