Electrochemical performance of a lead fluoride electrode mixed with carbon in an electrolyte containing triphenylboroxine as an anion acceptor for fluoride shuttle batteries

In fluoride shuttle batteries (FSBs), the addition of an anion acceptor (AA) is required to dissolve the supporting electrolyte salt in an organic solvent. Based on theoretical calculations and practical experiments, the effectiveness of triphenylboroxine (TPhBX) as an AA for FSB was verified. Using an electrolyte with TPhBX as an AA, the specific capacities of the following two types of lead fluoride (PbF₂) electrodes were evaluated: (i) PbF₂ pulverized using a ball mill, (ii) pulverized PbF₂ mixed with carbon using a ball mill. The experimental results indicate that mixing PbF₂ with carbon using a ball mill increases the specific capacity of PbF₂ electrode

Electrochemical properties of lead fluoride electrode in fluoride shuttle battery

Recently, the reversible discharge and charge reaction of BiF₃ electrode for fluoride shuttle battery (FSB) that can be used as a promising candidate for next-generation battery are observed using a liquid-based electrolyte. In this study, we investigate the electrochemical performance of PbF₂ as an active material for the FSB. To increase the electronic conductivity, the PbF₂ was mixed with carbon, and the composite material between PbF₂ and carbon, PbF₂/C, is formed. High discharge and charge capacities are obtained for PbF₂/C during the first cycle. Although the discharge and charge capacities gradually decreased, the discharge and charge reactions occurred in the second and third cycles. To confirm the progress of the discharge and charge reactions, the crystal structure change of the active material during discharging and charging in the first and second cycles is evaluated using X-ray diffraction (XRD). From the XRD results, the formation of Pb and PbF₂ during discharging and charging can be confirmed, indicating that the discharge (PbF₂ + 2e− → Pb + 2F−) and charge (Pb + 2F− → PbF₂ + 2e−) reactions progress in both the first and second cycles

Geometric transitions, Chern-Simons gauge theory and Veneziano type amplitudes

We consider the geometric transition and compute the all-genus topological string amplitudes expressed in terms of Hopf link invariants and topological vertices of Chern-Simons gauge theory. We introduce an operator technique of 2-dimensional CFT which greatly simplifies the computations. We in particular show that in the case of local Calabi-Yau manifolds described by toric geometry basic amplitudes are written as vacuum expectation values of a product vertex operators and thus appear quite similar to the Veneziano amplitudes of the old dual resonance models. Topological string amplitudes can be easily evaluated using vertex operator algebra.Comment: 16 pages, 2 figures, (v2,3) minor changes, to appear in Phys. Lett.

Improved electrochemical performances in a bismuth fluoride electrode prepared using a high energy ball mill with carbon for fluoride shuttle batteries

Bismuth fluoride (BiF₃) is a promising positive electrode material for fluoride shuttle batteries (FSBs) owing to its high theoretical specific capacity (302 mA h g⁻¹). However, it exhibits low practical capacity. The methods for preparing the electrode are known to have significant effects on battery performance. The mixture between BiF₃ and carbon, BiF₃/C, prepared by high energy ball milling method has been already approved in lithium ion batteries. With this method, a significant improvement over the discharge and charge capacities of the BiF₃/C electrode has been achieved. In this work, for the first time, BiF₃/C electrode has been used for FSB. Using BiF₃/C electrode significantly increased the discharge and charge capacities. To confirm the progress of the discharge and charge reactions of BiF3/C electrode, the crystal structure of active materials and oxidation state of Bi for the BiF₃/C electrode during discharging and charging has been investigated by X-ray diffraction and X-ray absorption fine structure. The results reveal that, with higher capacity values, discharge and charge reactions related to BiF₃/C have been realized

Infiltration of T Lymphocytes and Expression of ICAM-1 in the Hippocampus of Patients with Hippocampal Sclerosis

We and others have previously shown that reactive microglia express the major histocompatibility complex (MHC) class I and class II antigens in the hippocampus of patients suffering from epilepsy. Although the MHC glycoproteins serve as restriction elements for T lymphocytes, there is little information available regarding T lymphocytes in hippocampal sclerosis. In the present study, we investigated T lymphocyte infiltration in human hippocampi in four cases of epilepsy with hippocampal sclerosis, as well as in four control cases without neurological disease. No CD8- or CD4-positive T lymphocytes were seen in hippocampi from the control cases. In contrast, CD8- and CD4-positive T lymphocytes had infiltrated into the hippocampi of patients with hippocampal sclerosis. In addition, expression of intercellular adhesion molecule-1 was diffusely upregulated in the hippocampi with hippocampal sclerosis. These results indicate that T lymphocyte infiltration is involved in the pathology of hippocampal sclerosis

Development of stepping measurement device for evaluation of and training in walking

日常生活で杖をついたり,老人車などを押したりなど歩行能力の低下した人に対する簡便･安価で効果的な歩行訓練方法,訓練機器はない｡歩行能力の低下した人が体の移動を伴う歩行訓練をする場合,常に転倒の危険性を伴うために,介護者が必要であったり,転倒の不安のために動作が消極的になり,訓練の効果が半減する｡これに対して,ゆっくりとした足踏みは歩行能力の低下した人に対しては下肢筋力の強化,バランス訓練となり,歩行能力を向上させる｡しかし,足踏みが適切におこなわれているか,訓練の効果の程度についての評価ができなかった｡そこで,歩行能力の評価･訓練のために足踏み状態をモニタすることができる足踏み測定器を開発した｡本装置は,足踏みをするマット2枚およびノートパソコンなどから構成されている｡足踏み中における両脚立脚,左右それぞれの片脚遊脚の状態をマットスイッチのON,OFF状態にて判断する｡測定後,歩数,平均両脚立脚時間,平均片肺立脚時間などの解析･表示を行う｡最後に歩行能力が低下した被験者の足踏みを測定して,杖歩行など日常の歩行状態と足踏みの状態との関係を示し,足踏み測定の有効性についても検討した｡Although gait training equipment such as the bicycle ergometer and treadmill exists for patients whose walking ability is high, there is no appropriate gait training method or training instrument for patients whose walking ability has become impaired, who often use a cane or walker, etc. in the course of daily life. In the case of gait training for persons whose walking ability involves impaired locomotion, there is always the danger of a fall. Consequently, a caregiver is required, and the effect of the training is cut by half because the patient's anxiety about falling is exacerbated. Slow stepping affords strengthening and balance training of the leg muscles for patients whose walking ability has become low, and walking ability is improved. However, whether such training appropriately carries out stepping and the degree of the effect of such training has not been evaluated. Therefore, we have developed a stepping measurement device that monitors stepping for evaluation and training of walking ability. This system consists of two mat switches for stepping, a measuring circuit for stepping detection, and a book-sized personal computer with a PC card-type AD converter. This system can detect a left or right single stance phase and a double stance phase relative to the ON, OFF condition of the mat switch. After measurement, the following items are analyzed and displayed: ・number of steps, ・average time of double stance phase, ・the average time of single stance phase, and so on. Finally, we measured the stepping of subjects whose walking ability is low, and showed the relationship between daily walking conditions and stepping conditions. The effectiveness of this system was considered in light of the results

Activation of Protein Kinase B Induced by H2O2 and Heat Shock through Distinct Mechanisms Dependent and Independent of Phosphatidylinositol 3-Kinase

Protein kinase B (PKB) is a downstream target of phosphatidylinositol (PI) 3-kinase in the signaling pathway of growth factors, and is activated by cellular stress such as H2O2 and heat shock. To study the mechanism of the stress-induced activation of PKB, PI 3-kinase products were measured in stress-stimulated cells. Both PI 3, 4-bisphosphate and PI 3, 4, 5-trisphosphate increased in H2O2 -treated cells, and the elevation of these phospholipids and activation of PKB were concurrently blocked by wortmannin, a potent inhibitor of PI 3-kinase. In heat-shocked cells, the level of PI 3, 4-bisphosphate did not change while that of PI 3, 4, 5-trisphosphate increased slightly, and an association between PKB molecules was observed. Two active PKB fractions, presumably monomeric and oligomeric forms, were resolved from heat-shocked cells by gel filtration column chromatography. Activation of the former was suppressed by pretreatment with wortmannin, whereas the generation and activation of the latter were not blocked by the PI 3-kinase inhibitor. Only the monomeric form, but not the oligomeric form, was recovered from H2O2 -treated cells, and its activation was prevented by wortmannin. These results indicate that PKB is activated by two distinct mechanisms that are dependent and independent of PI 3-kinase in stress-stimulated cell