Enhanced Electrochemical Performance and Safety of LiNi0.88Co0.1Al0.02O2 by a Negative Thermal Expansion Material of Orthorhombic Al2(WO4)3.

LiNi0.88Co0.1Al0.02O2 (NCA) is attractive for high-energy batteries, but phase transition and side reactions leave large volume change and thermal runaway. In order to address the drawbacks, orthorhombic Al2(WO4)3, a cheap anisotropic negative thermal expansion material, was synthesized and adopted to modify NCA, and its effects on the electrochemical performance and safety of NCA were investigated using multifarious techniques. Al2(WO4)3 can greatly improve the rate performance, cyclability at different temperatures, thermal stability, and interface behavior and intensify charge transfer as well as decline the deformation and side reactions of NCA. The discharge capacity of the NCA modified with 5 wt % Al2(WO4)3 reaches 170.0 mA h/g at 5.0 C and 25 °C. After 100 cycles, the values of this electrode at 1.0 C and 25 °C and at 3.0 C and 60 °C are 164.2 and 148.7 mA h/g, respectively, much higher than those of the pure NCA under the same conditions. Moreover, Al2(WO4)3 declines the byproducts and cation mixing and decreases the released heat, strain, and charge-transfer resistance after cycles of NCA about 37.1, 33.0, and 32.8%, respectively. The improvement mechanism is discussed. It opens an effective avenue for the applications of energy materials by simultaneously adjusting heat, structure, interface, and deformation.

Negative Thermal Expansion Material: Promising for Improving Electrochemical Performance and Safety of Lithium-Ion Batteries.

Heat and deformation are responsible for poor performance and safety of batteries, but they cannot always be avoided. To address these two issues, ZrW2O8, a negative thermal expansion (NTE) material, was adopted to modify LiNi0.8Co0.1Mn0.1O2 (NCM811) to decline deformation via in situ absorption of the generated heat. The reversible capacity of NCM811 modified with 5 wt % of ZrW2O8 can remain at 180.6 mAh/g after 100 cycles at 60 °C and 1.0 C current rate, which increases the retention ratio of NCM811 by 14.8%, while the voltage difference between main redox peaks, Rct, strain after cycles, and heat from DSC of NCM811 are reduced about 47.8%, 81.0%, 28.2%, and 76.0%, respectively. According to various analysis results, the side reactions are also suppressed, and the enhancing mechanisms of ZrW2O8 for NCM811 were discussed. A general strategy is developed for the management of deformation using heat to improve performance and safety of batteries.

Association between intrarenal arterial resistance and diastolic dysfunction in type 2 diabetes.

BACKGROUND: In comparison to the well established changes in compliance that occur at the large vessel level in diabetes, much less is known about the changes in compliance of the cardiovascular system at the end-organ level. The aim of this study was therefore to examine whether there was a correlation between resistance of the intrarenal arteries of the kidney and compliance of the left ventricle, as estimated by measurements of diastolic function, in subjects with type 2 diabetes. METHODS: We studied 167 unselected clinic patients with type 2 diabetes with a kidney duplex scan to estimate intrarenal vascular resistance, i.e. the resistance index (RI = peak systolic velocity-minimum diastolic velocity/peak systolic velocity) and a transthoracic echocardiogram (TTE) employing tissue doppler studies to document diastolic and systolic ventricular function. RESULTS: Renal RI was significantly higher in subjects with diastolic dysfunction (0.72 +/- 0.05) when compared with those who had a normal TTE examination (0.66 +/- 0.06, p < 0.01). Renal RI values were correlated with markers of diastolic dysfunction including the E/Vp ratio (r = 0.41, p < 0.001), left atrial area (r = 0.36, p < 0.001), the E/A ratio (r = 0.36, p < 0.001) and the E/E' ratio (r = 0.31, p < 0.001). These associations were independent of systolic function, hypertension, the presence and severity of chronic kidney disease, the use of renin-angiotensin inhibitors and other potentially confounding variables. CONCLUSION: Increasing vascular resistance of the intrarenal arteries was associated with markers of diastolic dysfunction in subjects with type 2 diabetes. These findings are consistent with the hypothesis that vascular and cardiac stiffening in diabetes are manifestations of common pathophysiological mechanisms.

Vein diameter is a predictive factor for recanalization in treatment with ultrasound-guided foam sclerotherapy.

OBJECTIVE: Ultrasound-guided foam sclerotherapy (UGFS) is a low-cost and minimally invasive treatment option for varicose veins. There is a relative paucity of outcome reports. METHODS: UGFS procedures at a tertiary public hospital between 2010 and 2017 were studied. Either the great saphenous vein (GSV) or small saphenous vein (SSV) was treated. Pretreatment, in-treatment, 6-week, and 1-year post-treatment ultrasound reports were analyzed. The primary outcome was to determine whether vein diameter predicts obliteration failure. RESULTS: There were 457 treatments completed in 290 patients. The GSV was targeted in 372 (81%). Mean vein diameters of the GSV were not different from those of the SSV (GSV, 5.7 mm; SSV, 6.2 mm; P = .18); 109 (24%) had a Clinical, Etiology, Anatomy, and Pathophysiology score of at least 4. Of the 457 UGFS procedures, 360 (78.8%) were for primary veins. Baseline information, including vein diameter, was not different between primary and recurrent veins. At 6 weeks, complete obliteration, partial recanalization, and complete recanalization rates were 54.9%, 29.1%, and 16%, respectively. Of those with complete obliteration at 6 weeks, the recanalization rate at 1 year was 25%. Increasing vein diameter was associated with recanalization at 1 year (obliteration, 4.9 mm; recanalization, 5.7 mm; P = .03), especially for primary veins (4.8 vs 5.8 mm; P = .009). Multivariate analysis showed similar outcome. Vein diameter of >6 mm had good specificity (88%) but poor sensitivity (43%) for predicting obliteration failure. There were 15 (3%) new-onset deep venous thromboses reported on follow-up, all of which were from treatment of primary veins (P = .049). CONCLUSIONS: Only 44% of UGFS procedures were observed to have complete obliteration at 1 year after a single intervention. Significant recanalization developed at 1 year. Increased vein diameter was associated with recanalization. The impact on clinical recurrence is unknown.

Is nonalbuminuric renal insufficiency in type 2 diabetes related to an increase in intrarenal vascular disease?

OBJECTIVE: To investigate the role of intrarenal vascular disease in the pathogenesis of nonalbuminuric renal insufficiency in type 2 diabetes. RESEARCH DESIGN AND METHODS: We studied 325 unselected clinic patients who had sufficient clinical and biochemical information to calculate an estimated glomerular filtration rate (eGFR) using the Modified Diet in Renal Disease six-variable formula, at least two estimations of urinary albumin excretion rates (AER), and a renal duplex scan to estimate the resistance index of the interlobar renal arteries. The resistance index, measured as part of a complications surveillance program, was compared in patients with an eGFR < or >or=60 ml/min per 1.73 m(2) who were further stratified into normo- (AER <20), micro- (20-200), or macroalbuminuria (> 200 microg/min) categories. RESULTS: Patients with an eGFR <60 ml/min per 1.73 m(2) had a higher resistance index of the renal interlobar arteries compared with patients with an eGFR >or=60 ml/min per 1.73 m(2). However, the resistance index was elevated to a similar extent in patients with an eGFR <60 ml/min per 1.73 m(2) regardless of albuminuric status (normo- 0.74 +/- 0.01, micro- 0.73 +/- 0.01, and macroalbuminuria resistance index 0.75 +/- 0.11). Multiple regression analysis revealed that increased age (P < 0.0001), elevated BMI (P = 0.0001), decreased eGFR (P < 0.01), and decreased diastolic blood pressure (P < 0.01), but not an increased AER, were independently associated with an elevated resistance index in patients with impaired renal function. CONCLUSIONS: Subjects with type 2 diabetes and reduced glomerular filtration rate had similar degrees of intrarenal vascular disease, as measured by the intrarenal arterial resistance index, regardless of their AER status. The pathological mechanisms that determine the relationship between impaired renal function and AER status in subjects with type 2 diabetes remain to be elucidated.

Upper extremity non-contrast magnetic resonance venography (MRV) compared to contrast enhanced MRV and ultrasound.

PURPOSE: To assess feasibility, image quality and measured venous caliber of non-contrast MRV (NC-MRV) of central and upper extremity veins, compared to contrast-enhanced MRV (CE-MRV) and ultrasound (US) in healthy volunteers. MATERIALS AND METHODS: 10 subjects underwent NC-MRV and CE-MRV at 1.5 T, with comparison to US. Two radiologists evaluated MRI for image quality (IQ) and venous caliber. RESULTS AND CONCLUSIONS: NC-MRV is feasible, with inferior IQ but comparable venous caliber measurements CE-MRV (mean 7.9±4.58 mm vs. 7.83±4.62, p=0.13). Slightly larger upper limb caliber measurements were derived for NC-MRV and CE-MRV compared to US (NC-MRV 5.2±1.8 mm, CE-MRV 4.9±1.6 mm, US 4.5±1.8 mm, both p<0.001).