Determination of the safety level of an advanced lithium ion battery having a nanostructured Sn-C anode, a high voltage LiNi0.5Mn1.5O4 cathode, and a polyvinylidene fluoride-based gel electrolyte

In this work we evaluate the safety characteristics of an advanced Sn-C/EC:PC 1:1, LiPF₆ PVdF gel electrolyte (GPE)/LiNi_0.5Mn_1.5O₄ lithium ion polymer battery. The tests are performed by using a complex analysis that combines Differential Scanning Calorimetry (DSC) Thermal Gravimetric Analysis (TGA), and Mass Spectrometry (MS). This is a very convenient tool since it detects eventual thermal decomposition processes and provides information on the nature of their products. The results of the DSC-TGA-MS analysis are here reported and discussed. They demonstrate that both the anode and the cathode sides of the battery may stand temperatures up to ca. 200 °C without undergoing thermal decomposition. This is a convincing evidence that the Sn-C/LiNi_0.5Mn_1.5O₄ lithium ion polymer battery is safe.     

An RCE-based Associative Memory with Application to Human Face Recognition

Many models of neural network-based associative memory have been proposed and studied. However, most of these models do not have a rejection mechanism and hence are not practical for many real-world associative memory problems. For example, in human face recognition, we are given a database of face images and the identity of each image. Given an input image, the task is to associate when appropriate the image with the corresponding name of the person in the database. However, the input image may be that of a stranger. In this case, the system should reject the input. In this paper, we propose a practical associative memory model that has a rejection mechanism. The structure of the model is based on the restricted Coulomb energy (RCE) network. The capacity of the proposed memory is desibed by two measures: the ability of the system to correctly identify known individuals, and the ability of the system to reject individuals who are not in the database. Experimental results are given which show how the performance of the system varies as the size of the database increases up to 1000 individuals.     

A SnSb-C nanocomposite as high performance electrode for lithium ion batteries

A tin antimony based electrode has been synthesized in the form of nanometric particles housed into the pores of a protective, amorphous carbon matrix. Electrochemical results, obtained using this material as the working electrode in a lithium cell, suggested that the electrochemical process involves both SnSb intermetallic and Sn metal, present in the carbon matrix. Moreover, the results demonstrated that the optimized nanostructure prevents the mechanical drawbacks, associated with the volume changes during the alloying processes, which normally affect this class of materials. Finally, a lithium ion battery based on the SnSb-C electrode as the anode and lithium iron phosphate, LiFePO₄, as the cathode_, showed very promising performance.     

Insulin-like growth factor system abnormalities in hepatitis C-associated osteosclerosis. Potential insights into increasing bone mass in adults

Hepatitis C-associated osteosclerosis (HCAO) is a rare disorder characterized by a marked increase in bone mass during adult life. Despite the rarity of HCAO, understanding the mediator(s) of the skeletal disease is of great interest. The IGFs-I and -II have potent anabolic effects on bone, and alterations in the IGFs and/or IGF-binding proteins (IGFBPs) could be responsible for the increase in bone formation in this disorder. Thus, we assayed sera from seven cases of HCAO for IGF-I, IGF-II, IGF-IIE (an IGF-II precursor), and IGFBPs. The distribution of the serum IGFs and IGFBPs between their ternary ( approximately 150 kD) and binary (approximately 50 kD) complexes was also determined to assess IGF bioavailability. HCAO patients had normal serum levels of IGF-I and -II, but had markedly elevated levels of IGF-IIE. Of the IGFBPs, an increase in IGFBP-2 was unique to these patients and was not found in control hepatitis C or hepatitis B patients. IGF-I and -II in sera from patients with HCAO were carried, as in the case of sera from control subjects, bound to IGFBP-3 in the approximately 150-kD complex, which is retained in the circulation. However, IGF-IIE was predominantly in the approximately 50-kD complex in association with IGFBP-2; this complex can cross the capillary barrier and access target tissues. In vitro, we found that IGF-II enhanced by over threefold IGFBP-2 binding to extracellular matrix produced by human osteoblasts and that in an extracellular matrix-rich environment, the IGF-II/IGFBP-2 complex was as effective as IGF-II alone in stimulating human osteoblast proliferation. Thus, IGFBP-2 may facilitate the targeting of IGFs, and in particular IGF-IIE, to skeletal tissue in HCAO patients, with a subsequent stimulation by IGFs of osteoblast function. Our findings in HCAO suggest a possible means to increase bone mass in patients with osteoporosis.     

Upregulation of xanthine oxidase by lipopolysaccharide, interleukin-1, and hypoxia. Role in acute lung injury

LPS and selected cytokines upregulate xanthine dehydrogenase/xanthine oxidase (XDH/XO) in cellular systems. However, the effect of these factors on in vivo XDH/XO expression, and their contribution to lung injury, are poorly understood. Rats were exposed to normoxia or hypoxia for 24 h after treatment with LPS (1 mg/kg) and IL-1beta (100 microg/kg) or sterile saline. Lungs were then harvested for measurement of XDH/XO enzymatic activity and gene expression, and pulmonary edema was assessed by measurement of the wet/dry lung weight ratio (W/D). Although treatment with LPS + IL-1beta or hypoxia independently produced a 2-fold elevation (p < 0. 05 versus exposure to normoxia and treatment with saline) in lung XDH/XO activity and mRNA, the combination of LPS + IL-1beta and hypoxia caused a 4- and 3.5-fold increase in these values, respectively. XDH/XO protein expression was increased 2-fold by hypoxia alone and 1.3-fold by treatment with LPS + IL-1beta alone or combination treatment. Compared with normoxic lungs, W/D was significantly increased by exposure to hypoxia, LPS + IL-1beta, or combination treatment. This increase was prevented by treatment of the animals with tungsten, which abrogated lung XDH/XO activity. In conclusion, LPS, IL-1beta, and hypoxia significantly upregulate lung XDH/XO expression in vivo. The present data support a role for this enzyme in the pathogenesis of acute lung injury.