Effective Measures of Thickness Evolution of the Solid Electrolyte Interphase of Graphite Anodes for Li-Ion Batteries.

Upon forming, the intensity or thickness of the solid electrolyte interphase (SEI) in a Li-ion battery (LIB) evolves to various states depending on the cell materials and operation conditions. Despite a crucial role in comprehending the behaviors of an LIB, its quantitative measure is far from satisfactory mainly because of the undue complexity of the concentration profiles of the comprising chemical species. Here, we calculate the depth profiles of atomic mole fractions of C and F and their ratio as RC/F = C/F of graphite anodes for LIBs in comparison to an X-ray photoelectron spectroscopy (XPS) experiment. To this end, we take a differential equation approach to dC/dt*, where t* is the reduced XPS etching time for depth. As a result, the respective analytical expression derived for C, F, and RC/F(t*) is verified to accurately account for the experiment. Moreover, we show that RC/F(t*) in the j state can be practically expressed in Rj(t*)≃αj(t*)1/γ+ßj, where γ is a constant for a given anode. Based on this, we suggest ξj* = (αi + ßi - ßj)/αj as a measure of the SEI thickness evolution from the i to j state in terms of the cycle number. As an intriguing finding, the SEI thickness evolves up to about 3 times that of its initial state, beyond which it does not appear to grow any more.

Older Adults With Hip Arthroplasty: An Individualized Transitional Care Program.

BACKGROUND: Most older adults with hip fracture surgery experience functional decline (FD), causing devastating outcomes. However, few studies have examined the effects of nursing interventions to reduce FD for them. PURPOSE: The aim of the study was to evaluate an individualized transitional care program (ITCP) to reduce FD for older adults with hip arthroplasty. METHODS: The study was quasiexperimental, with a nonequivalent control group design. A total of 37 participants scheduled for hip arthroplasty were recruited-21 in the experimental and 16 in the control group. FINDINGS: Two weeks following surgery (i.e., just prior to discharge), the ITCP group displayed less fear of falling than the usual care group. Moreover, the experimental group displayed objectively less FD with increased activities of daily living and Timed Up and Go scores, 6 weeks after hip arthroplasty. CONCLUSIONS: This study provides evidence of the effectiveness of nurse-led rehabilitative practices to reduce FD in older adults with hip arthroplasty. CLINICAL RELEVANCE: The ITCP promoted individual physical functioning for older adults with hip arthroplasty. This study results can aid healthy transitions of elderly patients with other various diseases.

Favorable effects of skeletal muscle on bone are distinguished according to gender and skeletal sites.

OBJECTIVES: The aim of this study was to investigate associations between skeletal muscle mass and bone mineral density according to gender and skeletal sites. METHODS: Using the data from Korean National Health and Nutrition Examination Survey (KNHANES IV) 2009, a total of 711 males and 847 females over 65 years of age were evaluated. Bone mineral density (BMD) and body composition were assessed using dual-energy X-ray absorptiometry. RESULTS: Relative appendicular skeletal muscle (RASM) was positively related with the femur BMD with a stronger relationship in males (r = 0.207, p < 0.001) than in females (r = 0.095, p < 0.05). However, lumbar spine BMDs in both males and females did not show any significant associations with the RASM value. In the logistic regression for osteoporosis expressed as a decrease of risk per increase of RASM by 1 standard deviation (SD) of the same sex healthy reference group, the age- and BMI-adjusted odds ratio (OR) for osteoporosis was 0.42 (95% CI 0.12-0.76) in the femur neck and 0.24 (95% CI 0.07-0.76) in the total hip for males. Among females, the age- and BMI-adjusted OR for osteoporosis was 0.65 (95% CI 0.33-1.00), which showed importance only in the total hip. CONCLUSIONS: Higher RASM was significantly associated with lower risk for osteoporosis and the areas at the femur neck and total hip appeared to more likely be affected positively by muscle. Moreover, because males showed faster muscle loss with aging than females, the bones of males may be more prone to favorable effects of muscle.