Interiors of completely positive cones

A symmetric matrix $A$ is completely positive (CP) if there exists an entrywise nonnegative matrix $B$ such that $A = BB^T$. We characterize the interior of the CP cone. A semidefinite algorithm is proposed for checking interiors of the CP cone, and its properties are studied. A CP-decomposition of a matrix in Dickinson's form can be obtained if it is an interior of the CP cone. Some computational experiments are also presented

Cerebral microbleeds in the hippocampus indicative of cognitive impairment in Sprague Dawley rats

Both aging and hypertension are significant risk factors for the development of vascular pathology, the underlying cause of vascular cognitive impairment (VCI), which is the second most common cause of dementia. Cerebral microbleeds (CMBs) are small blood degradation products found in brain tissues accompanying aging, dementia, and cerebrovascular diseases (Lee et al., 2018), and are associated with a decrease in cognitive performance. Evidence has shown that in rodent brains CMBs can develop with aging and inflammation exacerbates the development. However, few studies have investigated the interactions among aging, hypertension, and cerebrovascular pathology. Previous studies conducted in our laboratory have shown a sex-dependent increase in blood pressure in male Sprague Dawley (SD) rats. Based on these findings, the goals of the current study are to define the relationship between age and the presence of 1) sub-acute cerebral microhemorrhage and/or 2) acute cerebral microhemorrhage, in spontaneously hypertensive male SD rats, in an effort to better understand the links between hypertension and VCI. SD rats at ages of 3 months, 8 months, and 16 months were acquired and their blood pressure levels were recorded. Brains were extracted, sectioned and stained to reveal any microbleeds in the hippocampus. The results support the hypothesis that there is an age-dependent increase in sub-acute CMBs in the hippocampus, but no relationship with acute CMBs could be drawn since there was no acute CMBs observed. This study demonstrates the positive relationship between sub- acute CMBs and age in an age-dependent hypertension animal model, and such understanding will further elucidate the pathological mechanisms involved in hypertension and VCI, and contribute to the discovery of future therapeutics in treating hypertension, vascular cognitive impairment and relate pathologies

Treatment of Nonalcoholic Fatty Liver Disease with Total Alkaloids in Rubus aleaefolius Poir

Total alkaloids in Rubus aleaefolius Poir (TARAP) is a folk medicinal herb that has been used clinically in China to treat nonalcoholic fatty liver disease (NAFLD) for many years. However, the mechanism of its anti-NAFLD effect is largely unknown. In this study, we developed a NAFLD rat model by supplying a modified high-fat diet (mHFD) ad libitum for 8 weeks and evaluated the therapeutic effect of TARAP in NAFLD rats as well as the underlying molecular mechanism. We found that TARAP could reduce the serum triglycerides (TG), total cholesterol (TC), and low-density lipoprotein (LDL-C) levels and increase the serum high-density lipoprotein (HDL-C) level in NAFLD rats. In addition, TARAP treatment reduced expression of fatty acid synthetase (FAS), and acetyl-CoA carboxylase (ACC) and upregulated the expression of carnitine palmitoyltransferase (CPT). Our results suggest that regulation of lipid metabolism may be a mechanism by which TARAP treats NAFLD

3D dendritic-Fe2O3@C nanoparticles as an anode material for lithium ion batteries

3D dendritic Fe2O3 nanoparticles wrapped with carbon (denoted as 3DD-Fe2O3@C hereafter) were synthesized.</p

Correlation between porosity, amorphous phase and CMAS corrosion behaviour of LaMgAl11O19 thermal barrier coatings

Calcium-magnesium-alumino-silicate (CMAS) attack is one of the significant failure mechanisms of thermal barrier coatings (TBCs), which can facilitate TBC’s degradation at elevated temperatures. To clarify the correlation between the porosity, CMAS corrosion behaviour, lanthanum magnesium hexaluminate (LaMgAl11O19, LMA) TBCs were prepared by atmospheric plasma spraying (APS) and then heat-treated at 1173K and 1523K, respectively. For comparison, LMA tablets were prepared by mechanical and cold isostatic pressing. CMAS attack at 1523K was carried out both for LMA tablets and LMA coatings. Their microstructure, phase composition, and crystallization behavior after CMAS attack were investigated using scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS), X-ray diffraction as well as differential scanning calorimetry (DSC). The results indicated that CMAS attack was arrested for LMA tablets due to the formation of a dense crystalline layer induced by the chemical interactions between LMA and CMAS glass, while the as-sprayed LMA coatings were completely penetrated by molten CMAS due to the presence of amorphous phase and connected pores. Although the isothermal heat-treatment promoted a crystallization of LMA coatings, much vertical cracks formed during heat-treatment. The heat-treated LMA coatings suffered a severer CMAS attack than the as-sprayed one, since the vertical cracks inevitably provided efficient infiltration paths for molten CMAS