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Isolation of the endohedral metallofullerenes is currently carried out via a multistage high-performance liquid chromatography (HPLC) method. However, this method is tedious and time-consuming work, making it difficult to obtain macroscopic quantities of pure endohedral metallofullerenes. We report herein a selective electrochemical reduction of the endohedral metallofullerenes from extracts of carbon soot and a convenient separation method of endohedral metallofullerenes and empty fullerenes. A chemical oxidation of the endohedral metallofullerene anions is also discussed.

Modeling studies of a furo[2,3-d]pyrimidine GSK-3 hit compound 1 superimposed onto the X-ray crystal structure of a legacy pyrazolo[3,4-c]pyridazine GSK-3 inhibitor 2 led to the identification of 4-acylamino-6-arylfuro[2,3-d]pyrimidine template 3. Synthesis of analogues based on template 3 has resulted in a number of potent and selective GSK-3beta inhibitors. The most potent and selective compound was the m-pyridyl analogue 24.

Probability measures are well-defined ones that satisfy additivity. However, it is slightly tight, because of its condition of additivity. Fuzzy measures that do not satisfy additivity have been proposed as substitute measures. The only belief function involves a density function in finite spaces among them. In this paper, we propose two probability functions by extending values of probability functions to interval values, which do not satisfy additivity. According to the definition of interval probability functions, lower and upper probabilities are defined, respectively, as known in Dempster--Shafer Theory. A combination rule and a conditional probability can be defined well. The properties of the proposed measure are clarified. Last, a numerical example with respect to Bayes' decision problems is shown.

Raw single-walled carbon nanotubes produced by arc discharge were first treated with K2S2O8 in dilute H2SO4 solution to generate oxygenated functional groups such as carboxyl, hydroxyl, and carbonyl on varying carbon components. Further functionalization with octadecylamine was carried out via a condensation reaction between an amine group and a carboxyl group with the assistance of dicyclohexylcarbodiimide. The attachment of long alkyl chains leads the sample to be soluble in tetrahydrofuran and other organic solvents. The thus obtained stable dispersion was subjected to dispersion-centrifugation recycles, and then the metal catalysts and varying carbon impurities were separated with carbon nanotubes. The advantage of this procedure lies in high-yield and nondestructive recovery of the target material. Optical absorption spectroscopic and thermogravimetric analyses show that about 60% of the nanotubes in the starting material is extracted with a purity more than 90 wt %.

Ce@C(82) is isolated by high-performance liquid chromatography (HPLC) and the cage symmetry is determined as C(2)(v)() by measuring the (13)C NMR spectra of its anion. The (13)C NMR peaks of [Ce@C(82)](-) show temperature-dependent shifts ascribed to the f electron remaining on the Ce atom. Both Ce@C(82) and [Ce@C(82)](-) are silent in electron spin resonance spectroscopy (ESR) because of the highly anisotropic g matrix as well as of the fast relaxation process originating from the orbital angular momentum of the f electron. This is the complementary relationship to the observation of the paramagnetic shift in (13)C NMR. [Ce@C(82)](-) has lower stability in air than [La@C(82)](-).

The simultaneous perturbation stochastic approximation (SPSA) is an extension of the Kiefer–Wolfowitz stochastic approximation algorithm. In SPSA, since all parameters are perturbed simultaneously, it is possible to modify parameters with only two measurements of an evaluation function regardless of the dimension of the parameter. We propose a parameter estimation algorithm using the SPSA. A convergence theorem for the proposed algorithm is shown. A simulation result also reveals the feasibility of the identification scheme proposed here. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(2): 30–39, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20239

Present cancer gene therapy using proapoptotic genes has had limited success because the therapy is prone to cause side effects as a result of the lack of tissue and cancer specificity. To target cancer cells without damaging normal cells, we have designed a novel dual promoter system in which a tissue-specific transcription system under the control of a cancer-specific promoter drives expression of a therapeutic gene. The applicability of this system was demonstrated by adapting it to target lung cancer. We termed this lung cancer system TTS (TTF1 gene under the control of human telomerase reverse transcriptase promoter and human surfactant protein A1 promoter). The TTS system showed much higher promoter activity in lung cancer cells compared with other kinds of cancer and normal lung cells, including stem cells. Moreover, insertion of negative glucocorticoid responsive elements in the system allows it to be drug controllable. The approaches that we have used could be adapted to target other types of cancer. We report a novel cancer-targeted tissue-specific dual promoter system designed for gene therapy.

To investigate the possible association of recurrent spontaneous abortions (RSA) of immune aetiologies with neonatal sex differences, karyotyping of abortuses from allo-immune RSA and epidemiological studies on the sex differences of neonates from sporadic aborters was carried out. Allo-immune disorders, as diagnosed by an increased number of shared HLA class II loci and reduced blocking activity of the woman's serum in mixed lymphocyte reaction, were found almost twice (54.9%) as often as auto-immune disorders (29.9%) among a total of 244 women with RSA. Of 33 abortuses karyotyped from women with RSA, 69.7% showed normal female karyotypes, while only 6.1% had normal male karyotypes, indicating that female fetuses are more prone to abort than males. Epidemiological studies revealed that boys were born at a significantly greater incidence of 58.1% in 221 women with a history of sporadic abortion than 47.6% in 893 women with no history of abortion. Moreover, the proportion of women giving birth to boys only was consistently and significantly higher, regardless of repeated deliveries, in sporadic aborters (36.7%) than in women with no history of abortion (19.6%), showing that more boys were born than girls to women with sporadic abortion. It is concluded that male fetuses are more likely to survive than females in allo-immune RSA due to allo-immune reproductive wastage of chromosomally normal female concept in early human pregnancy, and that allo-immune RSA makes up the highest proportion of unexplained RSA.

Organosilicon compounds represent a unique feature of materials such as disilane and polysilane. Meanwhile, since the isolation of C60 and C70 in preparatively useful quantities, much attention has been devoted to chemical functionalization of these new allotropic forms of carbon, which continuously yields fascinating results. It can be expected that a combination of organosilicon compounds and fullerene forms a new class of organic compounds and at the same time opens a new field in material science. In this context, we have carried out the reaction of fullerenes with active species generated in photolysis of disilane and polysilane, by which we can obtain an attractive material and also clarify the chemical and electronic properties of fullerenes. We here summarize the recent advances in the chemistry of mono- and bis-silylation of fullerenes with silylene and silyl radical to afford the corresponding new fullerene-based organosilicon materials.

A photochemical reaction of C(60) with disilane in a 2:3 ratio affords the isomer mixture of the tetrakis-adduct of C(60)((t)BuPh(2)Si)(4) as the major product. The use of a three-stage HPLC separation system isolated three of their isomers. Their structural assignments were based on FAB mass, UV-vis, NMR, and cyclic voltammetry (CV) measurements. The CV analysis showed that the terakis-adduct has lower oxidation and higher reduction potentials than the bis-adduct C(60)((t)BuPh(2)Si)(2) and the parent C(60).

Density functional calculations are carried out for the La2@C80 derivatives to investigate whether the motion of metals encapsulated inside fullerenes is controlled by exohedral addition. It is shown that the three-dimensional random motion of two La atoms in La2@C80 can be restricted to the circular motion in a plane by attaching electron-donating molecules on the outer surface of the C80 cage. It is expected that the two-dimensional circular motion will help to induce a unique electronic or magnetic field.

CBP/p300 recruitment to enhancer-bound complexes is a key determinant in promoter activation by many transcription factors. We present a novel mechanism of activating such complexes and show that pre-assembled Elk-1–p300 complexes become activated following Elk-1 phosphorylation by changes in Elk-1–p300 interactions rather than recruitment. It is known that Elk-1 binds to promoter in the absence of stimuli. However, it is unclear how activation of Elk-1 by mitogen-acivated protein kinase (MAPK)-mediated phosphorylation leads to targeted gene transactivation. We show that Elk-1 can interact with p300 in vitro and in vivo in the absence of a stimulus through the Elk-1 C-terminus and the p300 N-terminus. Phosphorylation on Ser383 and Ser389 of Elk-1 by MAPK enhances this basal binding but, most importantly, Elk-1 exhibits new interactions with p300. These interaction changes render a strong histone acetyltransferase activity in the Elk-1-associated complex that could play a critical role in chromatin remodeling and gene activation. The pre-assembly mechanism may greatly accelerate transcription activation, which is important in regulation of expression of immediate-early response genes, in particular those involved in stress responses.

Neural networks are widely used for many fields including control problems. When we use a neural network as a controller, the direct inverse control scheme is the simplest approach. However, the scheme using the back-propagation method requires information, e.g. Jacobian, of an objective. If the objective is nonlinear, it will be difficult to know the information. Using the simultaneous perturbation learning rule, we can construct a neuro-controller, which is an inverse system of the objective or a proper controller, under the direct inverse control scheme without any information on the objective.In this paper, we report a tracking control for a two link robot arm using a neuro-controller with the simultaneous perturbation learning rule. Details of the proposed control scheme are described. Some simulation results and a result for a real two link robot arm show that the control scheme is feasible and useful.

The purpose of this research is to make a calibration-free robot arm system which has a vision based controller. The system operation is carried out based on the simultaneous perturbation method.Generally speaking, many robot systems involve a kind of vision-based controller which is able to control positions of a manipulator with explicit calibration of camera and robot parameters. However, these systems require much information about geometry of camera parameters and kinematics of the system. At the same time, calibration itself will be a time-consuming process as well. As a result, these systems become relatively complex. Moreover, if circumstances or camera parameters change, we have to recalibrate the system.In this paper, we would like to propose a calibration-free robot control system using the simultaneous perturbation method. By using the simultaneous perturbation method, the system does not require any information on the robot or the camera. Actually, we can move the tip of the robot arm to goal point without any information on the system. Actual experiments show feasibility and usefulness of the proposed system.

C(60) acts as a mechanistic probe for the formation of carbene, diazo compound, and for the rearranged product via the excited state in the photolysis of 3-chloro-3-isopropyldiazirine and 3-chloro-3-chloromethyldiazirine. The carbene adds to C(60) to form methanofullerene, whereas the diazo compound adds to C(60) to form fulleroid. The olefin product arises as a result of the rearrangement in the excited state.

A stable diamagnetic mono-anion of the major isomer of Pr@C 82 (Pr@C 82 –A) was electrochemically prepared and isolated to determine the symmetry of its carbon cage. By measurement of the 13 C NMR spectrum of the anion, Pr@C 82 –A is found to have C 2v symmetry.

Nuclear receptors (NR) activate transcription by interacting with several different coactivator complexes, primarily via LXXLL motifs (NR boxes) of the coactivator that bind a common region in the ligand binding domain of nuclear receptors (activation function-2, AF–2) in a ligand-dependent fashion. However, how nuclear receptors distinguish between different sets of coactivators remains a mystery, as does the mechanism by which orphan receptors such as hepatocyte nuclear factor 4α (HNF4α) activate transcription. In this study, we show that HNF4α interacts with a complex containing vitamin D receptor (VDR)-interacting proteins (DRIPs) in the absence of exogenously added ligand. However, whereas a full-length DRIP205 construct enhanced the activation by HNF4α in vivo, it did not interact well with the HNF4α ligand binding domain in vitro. In investigating this discrepancy, we found that the polyamine spermine significantly enhanced the interaction between HNF4α and full-length DRIP205 in an AF-2, NR-box-dependent manner. Spermine also enhanced the interaction of DRIP205 with the VDR even in the presence of its ligand, but decreased the interaction of both HNF4α and VDR with the p160 coactivator glucocorticoid receptor interacting protein 1 (GR1P1). We also found that GR1P1 and DRIP205 synergistically activated HNF4α-mediated transcription and that a specific inhibitor of polyamine biosynthesis, α-difluoromethylornithine (DFMO), decreased the ability of HNF4α to activate transcription in vivo. These results lead us to propose a model in which polyamines may facilitate the switch between different coactivator complexes binding to NRs.

Photochemical silylations of higher fullerenes (C70, C76(D2), C84(D2)) are reported. During the photochemical cycloaddition of these higher fullerenes with disilirane, the formation of mono-adducts was observed. Since the highly selective disilirane addition to C70 was observed, the reaction of C76(D2) and C84(D2) with disilirane gave at least eight and seven isomers of the mono-adduct, respectively. These adducts were isolated in their pure form by multistage HPLC. The electronic properties of these adducts were also investigated using differential pulse voltammetry. The results indicate that silylation is very effective for producing the electronegative higher fullerene derivatives.

The purpose of this paper is to develop a new DEA with an interval efficiency. An original DEA model is to evaluate each DMU optimistically. There is another model called “Inverted DEA” to evaluate each DMU pessimistically. But, there are no relations essentially between DEA and inverted DEA. Thus, we formulate a DEA model with an interval efficiency which consists of efficiencies obtained from the optimistic and pessimistic viewpoints. Thus, two end points can construct an interval efficiency. With the same idea, we deal with the interval inefficiency model which is inverse to interval efficiency. Finally, we extend the proposed DEA model to interval data and fuzzy data.

Although an exogenous EGF is dispensable for EGFRL858R-mediated NIH3T3 cell transformation in vitro (Greulich et al., PLoS Med 2005), an exogenous EGF promotes growth of H1650 and H1975 lung adenocarcinoma cells that carry EGFR mutations in vitro (Sordella et al., Science 2004). However, it is unknown whether an exogenous EGFR ligand plays a role in growth of EGFR-mutant lung tumors in vivo. Here, using conditional transgenic mice expressing EGFRL858R or KRASG12D along with an exogenous TGFalpha (an EGFR ligand) in lung epithelium, we sought to determine the role of an EGFR ligand in EGFRL858R-lung tumors or wild type EGFR-lung tumors (KRASG12D-lung tumors) in vivo. As previously reported, conditional expression of TGFalpha (an EGFR ligand) in lung epithelium caused pulmonary fibrosis but not lung tumors (Korfhagen et al., J Clin Invest 1994; Hardie et al., AJP-LCMP 2004), indicating that the expression of an exogenous EGFR ligand is not sufficient to induce lung tumors. Conditional expression of EGFRL858R or KRASG12D in lung epithelium caused lung tumors as previously reported (Fisher et al., Genes Dev 2001; Politi et al., Gene Dev 2006). In our study using a new rtTA driver, Scgb1a1-rtTA line 2 (Perl et al., AJRCMB 2006), the majority of EGFRL858R-lung tumors occurred in alveolar regions while KRASG12D-lung tumors occurred in both alveolar and airway regions. Importantly, co-expression of EGFRL858R along with TGFalpha in lung epithelium induced the growth of lung tumors in airway regions but not in alveolar regions while the expression of EGFRL858R alone did not induce lung tumors in airway regions. Co-expression of EGFRL858R along with TGFalpha also shortened survival of the mice compared to the expression of either EGFRL858R or TGFalpha alone (median 32 days for EGFRL858R/TGFalpha vs 118 days for EGFRL858R alone or 248 days for TGFalpha alone). Co-expression of KRASG12D with TGFalpha did not influence tumor location or survival of the mice compared to the expression of either KRASG12D or TGFalpha alone. Consistent with the mouse study, TGFalpha expression in human EGFR-mutant lung cancer but not wild-type EGFR lung cancer was associated with worse overall survival (median 44 months for TGFalpha high vs 75 months for TGFalpha low; p Citation Format: Koichi Tomoshige, Yutaka Maeda. TGFalpha (an EGFR ligand) promotes growth of EGFR-mutant lung tumors in airway regions but not in alveolar regions in a transgenic mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1838. doi:10.1158/1538-7445.AM2017-1838

Photoreaction of C60 and C70 with adamantylideneadamantane or sulfide under oxygen flow gives fullerene epoxide together with adamantylideneadamantane epoxide or sulfoxide via peroxide intermediates.

We report on a superoutburst of the AM CVn-type object SDSS J090221.35+381941.9 [J0902; orbital period 0.03355(6) d] in 2014 March-April. The entire outburst consisted of a precursor outburst and the main superoutburst, followed by a short rebrightening. During the rising branch of the main superoutburst, we detected growing superhumps (stage A superhumps) with a period of 0.03409(1) d. During the plateau phase of the superoutburst, superhumps with a shorter period (stage B superhumps) were observed. Using the orbital period and the period of the stage A superhumps, we were able to measure the dynamical precession rate of the accretion disk at the 3:1 resonance, and obtained a mass ratio (q) of 0.041(7). This is the first successful measurement of the mass ratio in an AM CVn-type object using the recently developed stage A superhump method. The value is generally in good agreement with the theoretical evolutionary model. The orbital period of J0902 is the longest among the outbursting AM CVn-type objects, and the borderline between the outbursting systems and systems with stable cool disks appears to be longer than had been supposed., Comment: 6 pages, 4 figures, accepted for publication in PASJ

Reactions of Sc3N@I(h)-C80 with aziridine derivatives were conducted to afford the corresponding mono-adducts. A pair of diastereomers of the mono-adduct [5,6]-pyrrolidino-Sc3N@I(h)-C80 was isolated and characterized by means of mass spectrometry, vis-NIR absorption spectroscopy, and electrochemical measurements. Structural analysis of the mono-adducts was conducted by NMR and single-crystal X-ray structure determinations.

In this paper, we propose a position control scheme for actual robot system using high dimensional neural networks. Complex-valued neural network and quaternion neural network learn inverse kinematics of the robot systems. Control objectives are two dimensional SCARA robot and three dimensional robot. Tip of these robots are controlled by the high dimensional neural networks. Some results by an actual robot system are shown to confirm feasibility of these high dimensional neural networks as robot controllers.

The geometries of fullerenes are governed by the isolated pentagon rule (IPR), which states that stable fullerenes have each of their 12 pentagons surrounded by five hexagons. At the dawn of fullerene science, it was widely believed that the IPR would also be applicable for endohedral fullerenes. In 2000, that idea was altered by the discovery of the first non-IPR fullerenes, Sc2@C66 and Sc3N@C68. The structural data for Sc2@C66 were interpreted to indicate the presence of a pair of doubly fused pentagons. However, that structure has remained a long-standing mystery, since it is thermodynamically unfavorable. Here, we demonstrate definitively that Sc2@C66 does not have the structure that was long believed to be but a brand new type. 2D NMR spectroscopic and single-crystal X-ray analyses disclose that Sc2@C66 has a C2v(4059)-C66 cage containing two sets of unsaturated linear triquinanes (ULTs), in which three pentagons abut one another and two scandium ions are located within the folds of each of the ULT units.

Rationale: Goblet cell metaplasia accompanies common pulmonary disorders that are prone to recurrent viral infections. Mechanisms regulating both goblet cell metaplasia and susceptibility to viral infection associated with chronic lung diseases are incompletely understood. Objectives: We sought to identify the role of the transcription factor FOXA3 in regulation of goblet cell metaplasia and pulmonary innate immunity. Methods: FOXA3 was identified in airways from patients with asthma and chronic obstructive pulmonary disease. We produced transgenic mice conditionally expressing Foxa3 in airway epithelial cells and developed human bronchial epithelial cells expressing Foxa3. Foxa3-regulated genes were identified by immunostaining, Western blotting, and RNA analysis. Direct binding of FOXA3 to target genes was identified by chromatin immunoprecipitation sequencing correlated with RNA sequencing. Measurements and Main Results: FOXA3 was highly expressed in airway goblet cells from patients with asthma and chronic obstructive pulmonary disease. FOXA3 was induced by either IL-13 or rhinovirus. Foxa3 induced goblet cell metaplasia and enhanced expression of a network of genes mediating mucus production. Paradoxically, FOXA3 inhibited rhinovirus-induced IFN production, IRF-3 phosphorylation, and IKKe expression and inhibited viral clearance and expression of genes required for antiviral defenses, including MDA5, RIG-I, TLR3, IRF7/9, and nuclear factor-κB. Conclusions: FOXA3 induces goblet cell metaplasia in response to infection or Th2 stimulation. Suppression of IFN signaling by FOXA3 provides a plausible mechanism that may serve to limit ongoing Th1 inflammation during the resolution of acute viral infection; however, inhibition of innate immunity by FOXA3 may contribute to susceptibility to viral infections associated with chronic lung disorders accompanied by chronic goblet cell metaplasia.

Continuing the project described by Kato et al. (2009, PASJ, 61, S395, arXiv:0905.1757), we collected times of superhump maxima for 56 SU UMa-type dwarf novae mainly observed during the 2013-2014 season and characterized these objects. We detected negative superhumps in VW Hyi and indicated that the low number of normal outbursts in some supercycle can be interpreted as a result of the disk tilt. This finding, combined with the Kepler observation of V1504 Cyg and V344 Lyr, suggests that the disk tilt is responsible for modulating the outburst pattern in SU UMa-type dwarf novae. We also studied the deeply eclipsing WZ Sge-type dwarf nova MASTER OT J005740.99+443101.5 and found evidence of a sharp eclipse during the phase of early superhumps. The profile can be reproduced by a combination of the eclipse of the axisymmetric disk and the uneclipsed light source of early superhumps. This finding confirms the lack of evince of a greatly enhanced hot spot during the early stage of WZ Sge-type outburst. We detected growing (stage A) superhumps in MN Dra and give a suggestion that some of SU UMa-type dwarf novae situated near the critical condition of tidal instability may show long-lasting stage A superhumps. The large negative period derivatives reported in such systems can be understood a result of the combination of stage A and B superhumps. The WZ Sge-type dwarf novae AL Com and ASASSN-13ck showed a long-lasting (plateau-type) rebrightening. In the early phase of the rebrightening, both objects showed a precursor-like outburst, suggesting that the long-lasting rebrightening is triggered by a precursor outburst., Comment: 73 pages, 88 figures, accepted for publication in PASJ

A stable diamagnetic monoanion of the La@C82 isomer was electrochemically prepared and isolated in order to disclose its cage symmetry. By measuring the 13C NMR spectrum of the anion, it was determined for the first time that the isomer has Cs symmetry, as was also confirmed by density functional calculations.

The effect of the diffusive motion in a short time range on the nuclear resonant quasielastic scattering spectrum is presented. The solution of the Langevin equation, which describes the motion of ...

Nuclear resonant quasielastic scattering from ferrous cations in ion-exchange Nafion membranes was measured at room temperature, and the intrinsic dynamics of the cations inside the spherical regions surrounded by the sulfonic groups of Nafion was studied. For the analysis, the formula of nuclear resonant absorption for a particle diffusing in a sphere with an impermeable surface was derived. The formula indicates that the effect of the surface upon the diffusive motion is small if the radius of the sphere is larger than a critical value; in the case of 57 Fe ions, the value is about 2 A. As the radius of the spherical regions in our Nafion samples is estimated to be about 5 A, the existence of the surface can be ignored and the intrinsic dynamics of Fe cations can be extracted. The diffusion coefficient estimated from the least squares fit was (1.12±0.13)×10 -5 cm 2 /s for 15 wt% water content. This value is in good agreement with that of Fe cations in an HCl solution. As a result, Fe cations in Nafion d...

We have investigated the crystal structure and the Au valence states in [Au I X(DBS)][Au III X 3 (DBS)] (X=Cl, Br. I). From the analysis of 197 Au Mossbauer spectra in AuCl x (DBS) (X=1,2,3), it is proved that AuCl 2 (DBS) has a mixed-valence state of Au I and Au III Comparing with the isomer shifts of Au I and Au III in Cs 2 [Au I Cl 2 ][Au III Cl 4 ]. it is considered that the charge transfer interaction between Au I and Au III in AuCl 2 (DBS) is smaller than that in Cs 2 [Au I Cl 2 ][Au III Cl 4 ], The isomer shifts of Au I and Au III in AuCl 2 (DBS) are much larger than those in Cs 2 [Au I Cl 2 ][Au III Cl 4 ], which should be attributed to the highly covalent bond between Au and S. From the ESR spectra, it is shown that the Au II states exist as the mismatch of the valence alternation in AuCl 2 (DBS). The half-field ESR signal for ΔM=±2 at low temperature indicates the dimerization of the Au II state with ferromagnetic exchange interaction. Also, the X-ray powder patterns of AuX 2 (DBS) (X=Cl, Br) shows these two complexes to be isomorphous.

Electron transfer from cyclic silicon compounds to photo-excited C60 in polar solvents has been investigated by laser photolysis with observation of the transient absorption bands in the near-IR region. For three-, four- and five-membered cyclic silicon compounds in benzonitrile, the rise of the radical anion of C60 [C60−] was observed with the rapid decay of the triplet state of C60 [3C60*], indicating that electron transfer takes place via 3C60*. The rate constant (ket) and quantum yield (Φet) of electron transfer decrease with an increase in the number of silicon units. The ket and Φet values of the cyclic silicon compounds are smaller than those of the corresponding cyclic germanium compounds; an especially prominent difference was observed for four-membered cyclic compounds.

Activated carbon fibers (ACFs) composed of a nano-graphite disordered network have huge specific surface areas ranging 1000–3000m2g−1. The electronic states of iodine adsorbed in ACFs were investigated by 129 I Mossbauer spectroscopy with a focus on charge transfer from nano-graphite to iodine. The observed spectra consisting of five different quadrupole octets demonstrate the coexistence of I3 − ion and I2 molecule in micropores. This fact implies that l3 − ions are produced as a result of charge transfer from nano-graphite to iodine. The estimated charge transfer rate on the basis of the ratio of generated I3 − is in good agreement with the previous results obtained by magnetic susceptibility.

The second isomer of Pr@C82 (Pr@C82-II) has been isolated by a two-step HPLC method, separately from the known major isomer (Pr@C82-I). Visible and near-IR absorption spectra, as well as cyclic and differential pulse voltammograms show that the characteristic features of Pr@C82-II are significantly different from those of Pr@C82-I. The absorption peaks of Pr@C82-II have blue-shifts and the redox potentials have negative shifts, relative to those of Pr@C82-I. Chemical derivatization of both isomers with disilirane have also been achieved.

The choice of the learning scheme is very important in the implementation of neural networks to take advantage of their learning ability. Usually, the back-propagation method is widely used as a learning rule in neural networks. Since back-propagation requires so-called error back propagation to update weights, it is relatively difficult to realize hardware neural networks using the back-propagation method. In this paper, we present a pulse density neural network system with learning ability. As a learning rule, the simultaneous perturbation method is used. The learning rule requires only forward operations of networks to update weights instead of the error back-propaga- tion. Thus, we can construct the network system with learning ability without the need for a complicated circuit that calculates gradients of an error function. Pulse density is used to represent the basic quantities in this system. The pulse system has some attractive properties which includes robustness against a noisy environment. A combina- tion of the simultaneous perturbation learning rule and the pulse density system results in an interesting architec- ture of hardware neural systems. Results for the exclusive OR problem and a simple identity problem are shown.

Photophysical and photochemical properties of bis-silylated C60 derivatives have been examined using steady-state and time-resolved spectroscopies. Absorption band edges of 1,2- and 1,4-bis-silylated C60 derivatives ranged to about 800 nm. Fluorescence quantum yields of 1,2- and 1,16-adducts were slightly larger than that of C60, while 1,4-adducts did not show fluorescence. By laser irradiation to the bis-silylated C60 derivatives, transient absorption bands due to their triplet excited states were confirmed in the visible and near-IR regions. Photoinduced electron transfer from electron donor to excited triplet states of bis-silylated C60 derivatives was also confirmed in transient absorption spectra. The acceptor-abilities of the excited triplet states changed with the position of the C60-silicon bonds, which can be explained mainly on the basis of reduction potentials and triplet energies of the bis-silylated C60 derivatives.

Electric properties of chemically modificated carbon nanotubes (CNTs) using Si-containing organic molecules were investigated by means of the field effect transistors (FETs) technique, and presented the comparison of the FET properties between separated-individual and spread-sheet samples. From the results of FET measurement for both samples, it was shown that p-type CNTs–FETs can be converted to n-type ones by exohedral silylation. This results show that the characteristics of the CNTs–FET can be controlled by chemically modifications of outer surface of CNTs.

The photochemical reaction of C60 with disilane 1 affords the adduct 2 as a bissilylated product. The unique redox properties of 2 are reported by means of differential pulse voltammetry. The compound 2 was characterized by NMR, IR, and UV−vis spectroscopies. Spectroscopic and theoretical investigation strongly support the 1,16-addition structure having C2 symmetry which results from addition at the 1,16 positions in C60. The results are reasonably accounted for by the generation of a silyl radical which is responsible for the formation of 2.