This study showed that oxidative injuries could be involved in the pathogenesis of AD, as well as indicating that some antioxidant might be associated with the cognitive functions in AD.

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A clone for a rat acidic Ca2+-independent phospholipase A2(aiPLA2) was isolated from a cDNA library prepared from rat granular pneumocytes with a probe based on the human aiPLA2 sequence (T. S. Kim, C. S. Sundaresh, S. I. Feinstein, C. Dodia, W. R. Skach, M. K. Jain, T. Nagase, N. Seki, K. Ishikawa, N. Nomura, and A. B. Fisher. J. Biol. Chem. 272: 2542–2550, 1997). In addition, a consensus sequence for mouse aiPLA2 was constructed from several mouse cDNA clones in the GenBank and dbEST databases. Each sequence codes for a 224-amino acid protein with 88% identity of the amino acids among the three species and conservation of a putative lipase motif (GDSWG). Translation of mRNA produced from the rat clone in a wheat germ system resulted in expression of PLA2 activity with properties similar to those of the human enzyme, i.e., acidic pH optimum and Ca2+ independence. The localization of aiPLA2 in rat tissues was studied with the human cDNA probe, polyclonal and monoclonal antibodies, and aiPLA2activity. aiPLA2 is present in the lung as evidenced by high levels of mRNA and protein expression and by enzymatic activity that is inhibited by anti-PLA2 antibody and by the transition state analog 1-hexadecyl-3-trifluoroethylglycero- sn-2-phosphomethanol (MJ33). Immunocytochemistry showed the presence of aiPLA2 in alveolar type II cells, alveolar macrophages, and bronchiolar epithelium. In the brain, heart, liver, kidney, spleen, and intestine, aiPLA2 mRNA content was <50% of that in the lung, immunoreactive protein was not detectable, and enzymatic activity was not inhibited by MJ33 or aiPLA2 antibody. These results show marked enrichment of aiPLA2in the lung compared with the other organs and suggest translational control of aiPLA2 expression.

An electron transport is studied in the system which consists of scanning tunneling microscopysingle molecule magnet-metal. Due to quantum tunneling of magnetization in single-molecule magnet, linear response conductance exhibits stepwise behavior with increasing longitudinal field and each step is maximized at a certain value of field sweeping speed. The conductance at each step oscillates as a function of the additional transverse magnetic field along the hard axis. Rigorous theory is presented that combines the exchange model with the Landau-Zener model. PACS numbers: 75.45.+j, 75.50.Xx, 75.50.Tt Recently high-spin molecular nanomagnets such as Mn 12 or Fe 8 attracted lots of attention due to observation of quantum tunneling of magnetization and possible applications in information storage and quantum computing [1,2,3,4,5,6]. These single-molecule magnets (SMMs) exhibit steps in the hysteresis loops at low temperature, which is attributed to resonant tunneling between degenerate quantum states or quantum tunneling of magnetization(QTM). These unique features of SMMs are the consequence of long-living metastable spin states due to the large spin and strong anisotropy of SMMs. QTM also made it possible to detect the interference effect of Berry's phase on the magnetization at each step while the transverse field along the hard axis is varied [5,6]. Novel features of quantum tunneling are expected to manifest themselves in, if any, other observables. Especially the effects of QTM on the electronic transport remain to be explored in both experiments [7] and theories.In this paper we study theoretically the effects of QTM on the transport properties of SMMs which are deposited on a metallic surface with monolayer coverage. Placing the scanning tunneling microscopy(STM) tip right above one SMM, we compute the electric current which flows through a SMM when the bias voltage is applied between the STM tip and the metallic substrate (Fig. 1). We find that the linear response conductance increases stepwise like the magnetization of a SMM as a longitudinal magnetic field is increased. The stepwise behavior of conductance results from the QTM in SMM. The conductance at each step oscillates periodically as a function of additional transverse magnetic field along the hard axis. Our theoretical predictions are not known in the literature as far as we know and can be tested experimentally.When a finite bias voltage is applied between the STM tip and the metallic substrate, the electrons will tunnel through a vacuum between the metal surface and the STM tip. Since the STM tip is placed right above the SMM in our model system, the tunneling electrons may well be scattered by the large spin of a SMM. Our model system can be considered as the conventional tunnel junction with a SMM sandwiched between two normal metallic electrodes. The metallic substrate and STM tip are conveniently called the left(p = L) and right(p = R) electrodes, respectively. Two electrodes are described by the featureless conduction bands with the energ...

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We report on the thermopower of an Aharonov-Bohm (AB) interferometer with a quantum dot in the Kondo regime. The thermopower is anomalously enhanced due to the Kondo effect as in heavy fermion systems. In contrast to bulk systems, the sign of the thermopower can be changed by adjusting the energy level scheme or the particle-hole asymmetry of a dot with the gate voltage. Further the magnitude and even the sign of the thermopower in the AB ring can be changed at will with varying either magnetic fields or the gate voltages.

Spirituality, purpose in life, and trait anxiety contribute to different levels of resilience in patients with depression and/or anxiety disorders. Our results would deepen the understanding of resilience and provide potential targets of resilience-focused intervention in these patients.

The Connor-Davidson Resilience Scale (CD-RISC) is a brief self-rating questionnaire for measuring resilience. The aims of the present study were to describe the development of a Korean version of the CD-RISC (K-CD-RISC) and to more firmly establish its psychometric properties in terms of reliability and validity. The participants consisted of a general population sample (n=194) and psychiatric outpatients (n=127) with non-psychotic mood or anxiety disorders. The K-CD-RISC score means (standard deviation) were 65.9 (13.6) in the general population and 50.4 (20.5) in the psychiatric outpatients. The mean score of the general population was significantly higher than that of the psychiatric outpatients. Exploratory factor analysis revealed five factors, and the obtained factor structure was verified through confirmatory factor analysis. In the general population, the Cronbach's α coefficient of the K-CD-RISC was found to be 0.92. Greater resilience was found to be associated with less perceived stress, anxiety and depression and with higher levels of positive affect and purpose in life. Taken together, our findings suggest that the K-CD-RISC has good psychometric properties and is a valid and reliable tool for assessing resilience.