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When an electrodeposited CuSCN thin film was inserted into the interface of ITO/P3HT:PCBM blended solid film (P3HT: regioregular poly(3-hexylthiophene), PCBM: soluble [6,6]phenyl C61 buttyric acid methyl ester) in ITO/P3HT:PCBM/ Al sandwich-type solar cells, the cell performance was remarkably improved, resulting in 2.5% of energy conversion yield under the irradiation of AM 1.5-100 mW/cm(2) simulated sunlight.

A series of pi-extended bowl-shaped pi-conjugated compounds were synthesized from sumanene and characterized, and among them the terthiophene derivative showed a remarkable red-shifted absorption and small band gap, which wa rationalized by molecular orbital calculation.

The science of non-planar p-conjugated carbon molecules, represented by C60 and the carbon nanotube, has been attracting great interest due to their potential utility over interdisciplinary fields, such as electrical materials science, catalysis, and pharmaceutics. In this context, bucky-bowls are now considered to be another group of key materials in the science of curved p-conjugated carbon systems. Most of the investigation in bucky-bowl chemistry has focused on C5v symmetric corannulene and its derivatives. However, the methods to prepare functionalized corannulenes are still limited because the rim of corannulene consists of aromatic double bonds. On the other hand, sumanene (1), a partial C3v symmetric structure of fullerenes, is characterized by three benzylic positions, which may allow facile functionalization. In 2003, a synthesis of 1 under nonpyrolytic conditions was developed by our group. Stereoselective trisilylation at the benzylic positions via the corresponding trianion was achieved to afford a single diastereoisomer. X-ray analysis showed columnar p-stacking in a concave–convex fashion, suggesting that 1 may be of potential utility as electrically active materials in the solid state. In order to develop sumanene-based bucky-bowl chemistry, the method for carbon–carbon bond formation at its benzylic positions is considered to be an urgent issue. In the present research, 1,2-addition of benzylic anions to various aldehydes was investigated to extend p-conjugation, which is also of interest in view of non-planar p-conjugated carbon chemistry. Herein, we describe the facile synthesis, characterization and DFT calculation of extended p-conjugation systems derived from sumanene. The condensation of the benzylic anions of 1 with aldehydes was investigated to extend p-conjugation of 1 (Table 1). Various bases were examined for the condensation with benzaldehyde. The use of aqueous 30% NaOH solution as a base in the presence of tetrabutylammonium bromide and a minimum amount of THF gave 2a quantitatively as both C3 symmetric and unsymmetric diastereomers. Several substituted benzaldehydes (for 2b–f) were employed for the condensation reaction to control the electronic state of the p-conjugated systems. Seven derivatives 2a–g with extended p-conjugation were successfully synthesized in 68% to quantitative yield (Table 1).§ Condensation with [2,29;59,20]terthiophene-5-carbaldehyde gave 2h. The structures of these derivatives were supported by H-NMR, C-NMR and FAB-TOF mass spectrometry (HRMS). The color of 2a–f was yellow in CH2Cl2 solution, whereas that of 2g and 2h was orange and red, respectively. The diastereomer ratio (C3 symmetric and unsymmetric ones) of 2b and 2c was approximately 1 : 3, which was determined by the peak area of the methyl and methoxy groups of 2b and 2c, respectively, in the H-NMR spectra. UV–vis and emission spectra of 2a–h were measured in several solvents. Table 2 summarizes the absorption maxima, emission maxima and HOMO–LUMO band gaps. UV–vis and emission spectra of 1, 2a, 2g and 2h in CH2Cl2 solution are shown in Fig. 1a and Fig. 1b. The absorption maxima lmax of 2a were observed at 345 and 457 nm assignable to p–p*, which are 67 and ca. 150 nm red-shifted, respectively, as compared with those of 1. On the other

In the blended solid of poly(3-hexylthiophene-2,5-diyl) (P3HT) and porphyrin (TPP)/TiO2 p–n hetero-junction solar cells, a photo-induced charge transfer between P3HT and TPP accelerated the charge separation in the depletion layer formed at the P3HT+TPP/TiO2 interface, enhancing the photovoltaic properties. For the blended cell containing zinc porphyrin as TPP, the energy conversion yield of 0.26% was obtained under the illumination of solar simulated light AM1.5–100mW/cm2.

The effect of carrier mobility on the cell performance was examined in the bulk heterojunction solar cells consisting of soluble polythiophene (PHTh) and fullerene derivatives (PCBM). The hole mobility decreased from 6.3×10−3cm2V−1s−1 in the pure PHTh by blending PCBM, while the electron mobility decreased from 2.4×10−2cm2V−1s−1 in the pure PCBM by blending the PHTh. When blending ratio R=PHTh∕(PHTh+PCBM) by weight was 0.5–0.85, ambipolar carrier conduction was possible, showing the best-balanced ambipolar carrier mobility of ca. 10−4cm2V−1s−1 at R=0.7. The power conversion efficiency (η) of the PHTh:PCBM bulk heterojunction solar cells under AM1.5, 85mWcm−2 illumination significantly depended on the blending ratio R and the maximum η of 2.6% was observed at R=0.7, where both electrons and holes are conducting well. Thus, it was concluded that the ambipolar carrier conduction limits the performance of PHTh:PCBM bulk heterojunction solar cells.

Vectorcardiographic changes indicating old myocardial infarction were observed in eight of 288 patients who at autopsy did not show extensive myocardial disease. Of these eight patients four had been given a misdiagnosis of anteroseptal infarction, while four had been suspected of having anterolateral or anterior infarction on the basis of an abnormal configuration of the initial portion of the QRS loop. The possibility of overdiagnosis of myocardial infarction should be borne in mind in reading vectorcardiograms, especially in the absence of clear-cut history of the condition. A prominent Q wave simulating anteroseptal or anterior infarction was observed in lead V2 or V3, or in both in 12-lead electrocardiograms in all these eight cases. A high incidence of coronary sclerosis, scattered myocardial fibrosis and pulmonary em-

When the photosensitizing 3-ethyl-5-[3-ethyl-5-[2-(3-ethyl-2(3H)-benzothiazolylidene)ethylidene]-4-oxo-2-thiazolidinylidene]-2-thioxo-4-thiazolidinone (NK2097) was blended into the regioregular poly(3-hexylthiophene-2,5-diyl) (P3HT), the performance of the TiO2/P3HT + NK2097 sandwich-type solar cell was remarkably improved, resulting in 0.85% of energy conversion yield under the illumination of simulated sunlight with 100 mW/cm(2) intensity.

When an electrodeposited ZnO was inserted into the ITO/PV (PV: bisbenzimidazo[2,1-a:2',1'-a']antra[2,1,9-def:6,5, 10-d'e'f'] diisoquinoline-6,11-dione) interface in ITO/PV/MEH-PPV/Au sandwich-type solar cells (MEH-PPV: poly[2-methoxy-5-(2'-ethylenehexyloxy)-1,4-phenylenvinylene], the cell performance was remarkably improved, resulting in 1.24% of energy conversion yield under the irradiation of AM 1.5-100 mW/cm(2).

Erythropoietin receptor (EpoR) is expressed in the central nervous system (CNS), however, no clear consensus has been obtained whether Epo acts as a prosurvival factor in neurons. Because retinal ganglion cell (RGC) death is a common cause of reduced visual function in several ocular diseases, we explored whether Epo might potentially be beneficial in protecting RGCs from glutamate and nitric oxide (NO)-induced cytotoxicity, using isolated RGCs by a two-step panning method. Brain-derived neurotrophic factor (BDNF) was used as a positive control. EpoR mRNA was expressed in isolated RGCs, and EpoR protein was expressed on the RGCs in the normal and ischemic retinas. Epo had less potential to improve the survival of primary RGCs in serum-free medium than BDNF. In these cells, BDNF, but not Epo, downregulated the expression of Bim, a proapoptotic Bcl-2 family member that plays a key role in cytokine-mediated cell survival, suggesting a possible mechanism for this difference. When RGCs were cultured with glutamate or an NO-generating reagent, the survival of RGCs was compromised, and Bcl-2 expression was decreased in these cells. Both Epo and BDNF significantly reduced RGC death induced by glutamate and NO. In agreement with this, these factors reversed the Bcl-2 expression. These findings suggest that Epo may be a potent neuroprotective therapeutic agent for the treatment of ocular diseases that are characterized by RGC death.

The energy conversion efficiency of a two-layer organic solar cell consisting of a perylene pigment (PV) and regioregular polythiophene polymer (P3DT) was 0.99% under illumination with Simulated solar light (AM 1.5-100 mW cm(-2)). The photovoltaic mechanism is discussed on the basis of the ionization potential of the component materials. The photoinduced hole-transfer from PV to P3DT quickly occurred at the PV/P3DT interface because of the large free energy change of 1.2 eV, then the subsequent charge separation efficiently proceeded, resulting in a large short-circuit photocurrent of 6.5 mA cm(-2). On the other hand, the open-circuit photovoltage was only 0.42 V because the LUMO level of PV is close to the HOMO level of P3DT. The difference between the LUMO and the HOMO can be attributed to the open-circuit photovoltage.

We report here efficient air-stable p-n heterojunction organic solar cells with a structure consisting of an n-type insoluble perylene pigment penetrated by a p-type-conjugated polymer, where the interfacial area for photocurrent generation increases. The solar cells are easily produced by infiltrating a soluble-conjugated polymer intentionally into an opening among insoluble microcrystalline perylene layer under a saturated chloroform vapor. This approach can be regarded as an alternative convenient way to achieve bulk heterojunction solar cells. The cell performance is further enhanced by inserting an additional layer between the electrode and the photoactive layer to confine exciton in the photoactive layer. The overall attempt to improve the cell performance, so far, results in maximum quantum efficiency up to 45% under illumination of 485-nm monochromatic light and power conversion efficiency up to 1.9% under a simulated solar light (AM1.5) with a 100mWcm−2 intensity. The approach is promising to achieve practical efficiency because tuning the opening size can further widen the photoactive area.

When an electron acceptor, [2-[2-[4-(dimethylamino)phenyl]ethenyl]-6-methyl-4H-pyran-4-ylidene]propanedinitrile (DCM) was blended into poly[2-methoxy-5-(2'-ethylenehexyloxy)-1,4-phenylenevinylene] (MEH-PPV) in a TiO2/MEH-PPV/Au sandwich-type solar cell, the cell performance was remarkably enhanced, resulting in 0.47% of energy conversion yield under the irradiation of AM 1.5-100mW/cm(2).

We present a model composed of nonmonotonic neurons that recalls various target patterns from the same cue pattern depending on a given context pattern, which was essentially difficult for conventional neural network models. In this model, the state of the network is projected onto a subspace by desensitizing a part of neurons depending on the context, and shifts along a trajectory attractor in the subspace to reach the target state. The model can simulate an arbitrary finite state automaton without limitations of size, keeping the merits of distributed representation.

In the blended solid of merocyanine (MC) and polythiophene (PTh)/TiO2 p-n hetero-junction solar cells, a hole transfer from the excited state of MC to the ground-state of PTh accelerated the charge separation in the depletion layer formed at the TiO2/MC+PTh interface, enhancing the photovoltaic properties. That is, the blended solar cell is not a so-called Gratzel cell being sensitized by mono-layer dyes chemically adsorbed on the TiO2 electrode, but rather the enhanced photovoltaic properties are attributable to the dye- sensitization of the conjugated polymer.

An enhanced photocurrent was obtained in an Al/porphyrin-sensitized regioregular polythiophene (PTh) Schottky-barrier cell when the top energy level of the valence band of PTh solid was more negative than the HOMO energy level of porphyrin. However, when ortho-Substituted meso-phenylporphyrins were employed, the photocurrent enhancement decreased to about half compared to the case when nonsubstituted meso-phenylporphyrins were used. We conclude from these results that both a larger thermodynamic driving force for a photoinduced hole transfer from porphyrin to PTh and a closer distance between the two conjugating planes of porphyrin and PTh are necessary to obtain a larger photocurrent.

Here, we reported that a new carbon electrode prepared with an activated carbon was superior to a Pt sputtered electrode as the counter electrode of dye-sensitized solar cells. The photovoltaic performance was largely influenced by the roughness factor of carbon electrode. The open-circuit voltage increased by about 60mV using the carbon counter electrode compared to the Pt counter electrode because of positive shift of the formal potential for I3−/I− couple.

When an activated carbon electrode containing carbon black CB or poly(3,4-ethylene dioxythiophene polystylenesulfonate) PEDOT was employed as the counter electrode of dye-sensitized solar cells, the energy conversion efficiency was improved compared to that of the solar cells with a sputtered Pt counter electrode.

An enhanced photocurrent was observed for a two-layer cell consisting of a regioregular polythiophene (PTh) blended with metal-free porphyrin (H2tpp) and a perylene tetracarboxylic derivative (PV), compared to a PTh (without H2tpp)/PV two-layer cell. This is because photoexcited H2tpp molecules efficiently transfer holes to PTh molecules and then produced electrons in H2tpp molecules rapidly transfer to PV molecules at the mixed solid/PV interface. In the two-layer photocell with the mixed solid, H2tpp behaves as a sensitizer, PTh and PV solids as carrier transport layers, and the mixed solid/PV interface as a charge separation site. Power conversion efficiency attained to η=2.9% for the PTh (with H2tpp)/PV two-layer cell under monochromatic light with 6μWcm−2 intensity.