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Inherent nature of a heterogeneous catalytic reaction system represented by a correlation between kinetics and thermodynamics is revealed as harmonious coordination of the correlation parameter and the binding state of a key adsorbate when the system is at the optimum condition with maximum reaction rate. This interpretation comes from the newly obtained common results in different reaction settings and conveys the essence of the catalytic reaction. Pioneering work by Michel Boudart in 1968 based on Polanyi and Bronsted relations was a key guidance to an extended development by the present author in 1988. And now further advancement has been made and it leads us to conclude that if the reaction system follows such a correlation, there is a systematic framework acting to orchestrate the best reaction performance. This framework is an intrinsic part of catalysis. In consequence, a new definition is suggested for the extended Sabatier’s principle. The efficacy and profundity of analytical mathematics approach appear in the key equations as they disclose the fundamental nature of catalytic reactions. The optimum in catalysis is a delicately controlled state made possible by an essential balance between kinetics and thermodynamics.

We report the first ionization potentials (IP1) of the heavy actinides, fermium (Fm, atomic number Z = 100), mendelevium (Md, Z = 101), nobelium (No, Z = 102), and lawrencium (Lr, Z = 103), determined using a method based on a surface ionization process coupled to an online mass separation technique in an atom-at-a-time regime. The measured IP1 values agree well with those predicted by state-of-the-art relativistic calculations performed alongside the present measurements. Similar to the well-established behavior for the lanthanides, the IP1 values of the heavy actinides up to No increase with filling up the 5f orbital, while that of Lr is the lowest among the actinides. These results clearly demonstrate that the 5f orbital is fully filled at No with the [Rn]5f(14)7s(2) configuration and that Lr has a weakly bound electron outside the No core. In analogy to the lanthanide series, the present results unequivocally verify that the actinide series ends with Lr.

WP1066 is a well-known inhibitor of the JAK/STAT3 signaling pathway. By a screen of known small molecule inhibitors of various enzymes and protein factors, we identified WP1066 as a ceramide glucosyltransferase inhibitor. Ceramide glucosyltransferase catalyzes the first glycosylation step during glycosphingolipid synthesis. We found that WP1066 inhibited the activity of ceramide glucosyltransferase with an IC50 of 7.2 μM, and that its action was independent of JAK/STAT3 pathway blockade. Moreover, the modes of inhibition of ceramide glucosyltransferase were uncompetitive with respect to both C6-NBD-cermide and UDP-glucose.

Calculation problems such as "12x7÷3" can be solved rapidly and easily by using certain techniques; we call these problems "efficient calculation problems." However, it has been pointed out that many students do not always solve them efficiently. In the present study, we examined the effects of an intervention on 35 seventh grade students (23 males, 12 females). The students were instructed to use an overview strategy that stated, "Think carefully about the whole expression", and were then taught three sub-strategies. The results showed that students solved similar problems efficiently after the intervention and the effects were preserved for five months.

Self-regulated learning is a key competence for our knowledge-based society. The learning strategy use enhancement program developed earlier was called 'gakusyuhou-kouza' in Japanese. The program was provided by researchers and included lecture and practice about a learning strategy. The lecture was provided to give participants opportunities to experience cognitive psychology experiments and theoretical explanations with regard to the strategy. To facilitate the students' perception of the effectiveness of the strategy, firstly students solved a problem prior to receiving information about the strategy, then the researcher instructed them on the strategy. In order to examine the combined effect of researcher-provided instruction and school teacher-provided training, students' spontaneous use of lesson induction (LI) in their math class was analyzed. In this study, the researcher delivered the aptly-named researcher-provided instruction. It should be possible for the schoolteacher to provide that instruction, if the teacher has sufficient understanding of the relevant psychological mechanisms and some training in the conduct of cognitive experiments.

The tilted-foil method for producing spin-polarized radioactive isotope beams has been studied using the re-accelerated radioactive 8 Li and 123 In beams produced at Tokai Radioactive Ion Accelerator Complex (TRIAC) facility. We successfully produced polarization in a 8 Li beam of 7.3(5)% using thin polystyrene foils (4.2 μg/cm 2 ). The systematic study of the nuclear polarization as a function of the number of foils and beam energy has been performed, confirming the features of the tilted-foil technique experimentally. After the study, a spin-polarized radioactive 123 In beam, which is the heaviest ever polarized in its ground state by this method, has been successfully generated by the tilted-foil method, for the nuclear spectroscopy around the doubly magic nucleus 132 Sn.

HA14-1 is a Bcl-2 inhibitor that is widely used for studies of apoptosis. In the course of searching for a ceramide glucosyltransferase inhibitor that catalyzes the first glycosylation step of glycosphingolipid synthesis, we unexpectedly found that HA-14-1 also has the ability to inhibit ceramide glucosyltransferase. The IC50 value of HA14-1 against ceramide glucosyltransferase is 4.5μM, which is lower than that reported for Bcl-2 in vitro. Kinetic analyses revealed that HA14-1 is a competitive and mixed-type inhibitor with respect to C6-NBD-ceramide and UDP-glucose, respectively.

This Letter studies theoretically the effects of electrochemical reactions having short time constants on the electrochemical impedance spectroscopy (EIS). We have shown that fast reactions are not detected by EIS no matter how high observation frequencies we use when the relaxation of electrode potential is slow, or when the electrochemical contribution of fast reactions is weak at the stationary state where the impedance is measured. Then only the kinetic parameters of slow reactions are measurable, and they are the effective ones modified by fast reactions. The form of the modification and the analytical representation of the impedance are given explicitly.

The phorbol ester tetradecanoylphorbol acetate (TPA) induces promyelocytic leukaemia cells to differentiate to macrophage-like cells in vitro. During the course of this differentiation, the cells adhere to the bottom of the culture dish, a process that requires an increase in cell surface glycosphingolipids (GSLs). We examined the cellular content of glucosylceramide (GlcCer), the simplest of the GSLs, in a TPA-treated leukaemia cell line, U937. Following TPA treatment, we observed a 3.5-fold increase in GlcCer levels that was caused by enhanced activity of ceramide glucosyltransferase (GlcT-1), which catalyses ceramide glycosylation. Furthermore, in TPA-treated cell GlcT-1 amounts were increased at both the mRNA and protein levels. We also found decreased activity of lactosylceramide synthase in TPA-treated cells, which could also contribute to the increase in cellular GlcCer content.

The diffusion coefficients of Li in the NaTl-type Li intermetallic compound of β-LiGa have been measured by using a short-lived radioactive diffusion tracer. As the tracer, the α-emitting radioisotope of 8Li delivered as the energetic and pulsed beam from Tokai Radioactive Ion Accelerator Complex (TRIAC) was implanted into the β-LiGa compounds with the composition in the range of about 43 to 54 at.% Li. By analyzing the time-dependent yields of the α-particles measured according to the repetition cycle of the beam, the tracer diffusion coefficients were extracted over the wide range of Li composition. Abnormal composition-dependence of Li diffusion coefficients in β-LiGa was observed; the stoichiometric β-LiGa showed the highest diffusivity of Li. By referring to the composition-dependent diffusivity of Li in the iso-structural β-LiAl and β-LiIn, we could identify the abnormal diffusion of Li in very Li-poor composition of β-LiGa. The anomaly has been discussed qualitatively in terms of the formation of defect complex and the interaction between the constitutional defects.

The KEKCB is an electron cyclotron resonance ion source (ECRIS) operating at the microwave frequency of 18 GHz and has successfully operated as the charge breeder at Tokai Radioactive Ion Accelerator Complex (TRIAC). Following an overview of the TRIAC, the recent operating results of the KEKCB have been demonstrated. Special attention was paid on the element-dependent charge breeding efficiency and the beam impurity originating from the ECR plasma of the KEKCB.

For the ISOL-based radioactive ion beam facility, TRIAC, separation efficiencies and release times of neutron-rich isotopes produced in proton-induced fission of 238U have been measured using the JAEA-ISOL target/ion source systems. With a FEBIAD-B2 type integrated target–ion source, for example, we obtained separation yields, the values were normalized to a uranium target thickness of 1 g/cm2 and 1 μA primary proton beam current, 1.4 × 106 pps for 91Kr, 7 × 105 pps for 126In, 2.6 × 106 pps for 138Xe, respectively. Using a surface ionization type ion source, under the same normalization, the separation yields of 1.8 × 107 pps for 93Rb, 6 × 107 pps for 94Sr, 2.5 × 106 pps for 143Cs and 5 × 106 pps for 142Ba were observed. The release times of radioactive Rb, Cs, Ba, In, Kr and Xe atoms were measured using present target/ion source systems. Comparison of the measured yields of Ba, In and Xe isotopes with the calculated ones suggests that the long release time gave low separation efficiency for short-lived isotopes.

Non-destructive and on-line Li diffusion experiments in Li ionic conductors are conducted using the short-lived !-emitting radiotracer of 8Li. The radiotracers produced as an energetic and pulsed ion beam from TRIAC (Tokai Radioactive Ion Accelerator Complex) are implanted into a structural defect mediated Li ionic conductor of NaTl-type intermetallic compounds ("-LiGa and "-LiIn). The experimental time spectra of the yields of !-particles are compared with simulated results and Li diffusion coefficients in the intermetallic compounds are extracted with an accuracy of ±10%. The diffusion coefficients obtained for "-LiGa with Li content of 43-54 at.% are discussed in terms of the interaction between Li-ion and the structural defects in the specimen, compared with the cases of "-LiAl and "-LiIn. The nonlinear Li-content dependency of Li diffusion coefficients for "-LiGa suggests that the Li diffusion with the Li-deficient region is obstructed by the defect complex composed of vacancies at the Li sites.

Fatty liver disease is a condition in which abnormally large numbers of lipid droplets accumulate in liver cells. Fatty liver disease induces inflammation under conditions of oxidative stress and may result in cancer. To identify plants that protect against fatty liver disease, we examined the inhibitory effects of plant extracts on lipid droplet formation in mouse hepatoma cells. A screen of 98 water extracts of plants revealed 4 extracts with inhibitory effects. One of these extracts,Rubus suavissimusS. Lee (Tien-cha or Chinese sweet tea) leaf extract, which showed strong inhibitory effects, was tested in a mouse fatty liver model. In these mouse experiments, intake of the plant extract significantly protected mice against fatty liver disease without affecting body weight gain. Our results suggest that RSE directly affects liver cells and protects them from fatty liver disease.

Q β values of the neutron-rich isotopes of 160-165Eu and 163Gd were measured for the first time using a total absorption bismuth germanate (BGO) detector, and previously obtained data on 158, 159Pm , 159, 161Sm and 166Tb were re-analyzed. These radioactive sources were prepared by an on-line mass separator (Tokai-ISOL) following the 238U (p,f reaction. The deduced Q β values are the following: 6085(80)keV for 158Pm , 3805(65)keV for 159Sm , 5460(140)keV for 159Pm , 4705(60)keV for 160Eu , 5065(130)keV for 161Sm , 3705(60)keV for 161Eu , 5575(60)keV for 162Eu , 4690(70)keV for 163Eu , 3170(70)keV for 163Gd , 6430(70)keV for 164Eu , 5800(120)keV for 165Eu , and 4695(70)keV for 166Tb . Moreover, the deduced mass excesses and two-neutron separation energies ( S 2n values) were compared with those of the atomic mass evaluations and theoretical predictions.

An ISOL-based radioactive nuclear beam (RNB) facility, Tokai Radioactive Ion Accelerator Complex (TRIAC), has been jointly developed by High Energy Accelerator Research Organization (KEK) and Japan Atomic Energy Agency (JAEA). The facility started to supply RNBs for experiments in 2005 and RNBs including fission fragments with energies up to 1.1MeV/A are available in the present. Several experimental studies were performed successfully using 8Li beams with various energies.

We have cloned and characterized a novel splice variant of mouse GMx33alpha/Golgi-associated protein of 34 kDa (GPP34), hereby designated GMx33alphaV/GPP34V. This splice variant skips the second and third exons, and the resulting frame shift generates a stop codon in the fourth exon. GMx33alphaV/GPP34V is comprised of 81 amino acid residues derived from the N-terminal end of the full length protein and corresponds to approximately one-third of the full length GMx33alpha/GPP34 sequence with a calculated molecular mass of 8900. In contrast to GMx33alpha/GPP34 mRNA which is expressed at similar levels in various tissues, GMx33alphaV/GPP34V mRNA was differentially expressed when examined by RT-PCR. Compared to other tissues, skeletal muscle showed relatively strong expression of GMx33alphaV/GPP34V mRNA. This splice variant cDNA was also detected in a human cell line.

We have measured deexcitation γ rays in the neutron-rich nuclei of 240U, 246Pu, and 250Cm produced by the (18O, 16O) two-neutron transfer reactions, in coincidence with the 16O particles using Si ΔE−E detectors. The γ rays in these nuclei were identified by selecting the kinetic energies of 16O particles, which correspond to the excitation energies in the residual nuclei below the neutron separation energies. The ground-state bands of 240U, 246Pu, and 250Cm were established up to 12+ states and the K π = 0− octupole band of 240U was established up to 9− states. The systematics of the moments of inertia of the ground-state bands for actinide nuclei shows that the deformed subshell closure at N = 152 is sustained for 96Cm isotopes and that it disappears for 94Pu isotopes.

This study investigated factors promoting the use of self-constructed diagrams by examining students’ perceptions and daily class activities, and comparing Japanese (n ¼ 291) and New Zealand (n ¼ 323) students. Algebra word problems and a questionnaire were administered. The results revealed that the New Zealand students used diagrams more often and scored higher than their Japanese counterparts. Lack of confidence and perceptions of difficulty in diagram use, and viewing diagrams more as a strategy that teachers use, were found to link with lower use. Possible ways of promoting diagram use in math word problem solving are discussed.

The extraction behavior of rutherfordium (Rf) into tributylphosphate (TBP) from hydrochloric acid (HCl) has been studied together with those of the lighter group-4 elements Zr and Hf. The extractability of261Rf,169Hf, and85Zr into TBP was investigated under identical conditions in 7.2–8.0 M HCl by on-line reversed-phase extraction chromatography. The percent extractions of Rf, Hf, and Zr into the TBP resin increase steeply with increasing HCl concentration, and the order of extraction is Zr > Hf ≈ Rf. By considering the order of chloride complexation among these elements, it is suggested that the stability of the TBP complex of Rf tetrachloride is lower than those of Zr and Hf.

The excitation function of the 8 Li(d, t) 7 Li reaction was directly measured using 8 Li beam irradiating a deuterated polyethylene target at center-of-mass system beam energies ( E cm ) between 0.3 and 1.2 MeV. This is the first cross section measurement of the above reaction below E cm = 1.5 MeV , covering Gamow peaks for 1 – 3 × 10 9 K of astrophysical interest. A broad resonance-like structure was observed at around E cm = 0.8 MeV . The astrophysical reaction rate deduced from the present result is far larger than the previously reported values estimated from extrapolation of data observed at higher energies, roughly by one order of magnitude at about 1 × 10 9 K .

An overview of the current status of the 8.2 m Subaru Telescope constructed and operated at Mauna Kea, Hawaii, by the National Astronomical Observatory of Japan is presented. The basic design concept and the verified performance of the telescope system are described. Also given are the status of the instrument package offered to the astronomical community, the status of operation, and some of the future plans. The status of the telescope reported in a number of SPIE papers as of the summer of 2002 are incorporated with some updates included as of 2004 February. However, readers are encouraged to check the most updated status of the telescope through the home page, http://subarutelescope.org/index.html, and/or the direct contact with the observatory staff., Comment: 18 pages (17 pages in published version), 29 figures (GIF format), This is the version before the galley proof

Fluoride complexation of element 104, rutherfordium (Rf), produced in the 248Cm(18O,5n)261Rf reaction has been studied by anion-exchange chromatography on an atom-at-a-time scale. The anion-exchange chromatographic behavior of Rf was investigated in 1.9-13.9 M hydrofluoric acid together with those of the group-4 elements Zr and Hf produced in the 18O-induced reactions on Ge and Gd targets, respectively. It was found that the adsorption behavior of Rf on anion-exchange resin is quite different from those of Zr and Hf, suggesting the influence of relativistic effects on the fluoride complexation of Rf.

Lawrencium, with atomic number 103, has an isotope with a half-life of 27 seconds; even so, its first ionization potential has now been measured on an atom-at-a-time scale and agrees well with state-of-the-art theoretical calculations that include relativistic effects. The most dramatic modern revision of Mendeleev's periodic table of elements came in 1944 when Glenn T. Seaborg placed a new series of elements, the actinides (atomic numbers 89–103), below the lanthanides. In this issue of Nature, Yuichiro Nagame and colleagues report the first measurement of one of the basic atomic properties of element 103 (lawrencium), namely its first ionization potential. Lawrencium is only accessible via atom-at-a-time synthesis in heavy-ion accelerators, so experimental investigations of its properties are rare. Nagame and colleagues were able to reduce the number of atoms required to measure the ionization potential from billions to thousands, and these results — in agreement with the latest theoretical calculations — show that the last valence electron in lawrencium is the most weakly bound one in all actinides and any other element beyond group 1 of the periodic table. This signature — in a region of the periodic table where the sheer size of the atoms means that relativistic effects play a crucial role — confirms the end of the actinide series at element 103. The chemical properties of an element are primarily governed by the configuration of electrons in the valence shell. Relativistic effects influence the electronic structure of heavy elements in the sixth row of the periodic table, and these effects increase dramatically in the seventh row—including the actinides—even affecting ground-state configurations1,2. Atomic s and p1/2 orbitals are stabilized by relativistic effects, whereas p3/2, d and f orbitals are destabilized, so that ground-state configurations of heavy elements may differ from those of lighter elements in the same group. The first ionization potential (IP1) is a measure of the energy required to remove one valence electron from a neutral atom, and is an atomic property that reflects the outermost electronic configuration. Precise and accurate experimental determination of IP1 gives information on the binding energy of valence electrons, and also, therefore, on the degree of relativistic stabilization. However, such measurements are hampered by the difficulty in obtaining the heaviest elements on scales of more than one atom at a time3,4,5. Here we report that the experimentally obtained IP1 of the heaviest actinide, lawrencium (Lr, atomic number 103), is electronvolts. The IP1 of Lr was measured with 256Lr (half-life 27 seconds) using an efficient surface ion-source and a radioisotope detection system coupled to a mass separator. The measured IP1 is in excellent agreement with the value of 4.963(15) electronvolts predicted here by state-of-the-art relativistic calculations. The present work provides a reliable benchmark for theoretical calculations and also opens the way for IP1 measurements of superheavy elements (that is, transactinides) on an atom-at-a-time scale.

Nuclear decay properties of the neutron-deficient actinide isotopes 233,234,235,236Am and 237,238Cm have been investigated using a gas-jet coupled on-line isotope separator at the JAERI tandem accelerator facility. Alpha-decays of 233,235,236Am and 237,238Cm produced in the 6Li-induced reactions on 233,235U and 237Np targets have been observed with unambiguous mass identification, and the new isotopes 233Am and 237Cm have been identified for the first time. Alpha-particle energies, Qα values, half-lives and α-branching intensities were determined and the observed α decays of 233Am and 235Am are regarded as the favored transition.

Ceramides (Cers), critical for epidermal barrier function, also can inhibit keratinocyte proliferation, while glucosylceramides (GlcCers) exert pro-mitogenic effects. Since alterations in Cer-to-GlcCer ratios appear to modulate cellular growth versus apoptosis, we assessed whether keratinocytes up-regulate GlcCer synthesis as a protective mechanism against Cer-induced stress. Exogenous sphingomyelinase (SMase) treatment of cultured human keratinocytes (CHK) initially decreased proliferation and cellular sphingomyelin (50-60% decrease; P < 0.001), and increased Cer levels (6.1- to 6.8-fold; P < 0.001). Proliferation recovered to normal rates by 24 h, in parallel with increased cellular GlcCer. Both GlcCer synthesis and GlcCer synthase activity increased significantly by 8 h following SMase (8.2- and 2.4-fold, respectively; P < 0.01 each vs. control), attributed to antecedent increases in GlcCer synthase mRNA and protein expression. Further evidence that GlcCer production is responsible for normalized CHK proliferation includes: a) attenuation of SMase-induced inhibition of proliferation by exogenous GlcCer; and b) enhancement of the SMase effect in cells cotreated with the GlcCer synthase inhibitor, PDMP (D-threo-1-phenyl-2(decanoylamino)-3-morpholino-1-propanol). Finally, although proliferation in immortalized, nontransformed keratinocytes (HaCaT) also was inhibited by SMase, HaCaT cells that overexpress GlcCer synthase were resistant to this effect. Thus, SMase-induced stress initiates a response in keratinocytes that includes upregulation of GlcCer synthesis which may protect against the deleterious effects of excess Cer.

The transactinide nuclides261Rf and262Db have been successfully produced in the248Cm(18O,5n) reaction at 99 MeV and in the248Cm(19F,5n) reaction at 100, 103, and 106 MeV, respectively, at the JAERI tandem accelerator. The on-line ion exchange experiments with an automated fast and repetitive liquid chromatography separation system were performed in the HNO3/HF system using Rf homologues89mZr and167,165Hf produced in the89Y(p,n) and152Gd(18O,xn) reactions, respectively. The radiotracers88Zr,175Hf, and234Th were also prepared and the distribution coefficients on ion exchange resins were measured systematically in 1-11 M HCl and 1-14 M HNO3with the batch method. It was found that anion exchange experiments of Rf in 8 M HNO3and 9 M HCl provided information useful to extract the ionic radius of Rf and to verify the influence of relativistic effects.

Rat acetyl-CoA transporter gene (Acatn) encodes a hydrophobic multi-transmembrane protein involved in the O-acetylation of gangliosides. O-acetylated gangliosides have been found to play important roles in the embryonic development of the nervous system. We have isolated rat Acatn cDNA by PCR cloning. The amino acid sequence of rat Acatn exhibited 92% and 96% homology with human and mouse sequences, respectively. The mRNA was expressed in brain at all developmental stages. Acatn expression was higher in embryonic and postnatal rats than in adult rats. Cellular localization of Acatn mRNA in adult rat brain was also analyzed by in situ hybridization. Acatn mRNA expression was detected in the neuronal cells of cerebellum, hippocampus, hypothalamus, cortex, olfactory bulb, and dorsal and ventral anterior olfactory nucleus in adult rat brain.

$\ensuremath{\beta}$-decay half-lives of new neutron-rich isotopes ${}^{167}\mathrm{Tb}$ and ${}^{168}\mathrm{Tb}$ produced in the 20 MeV proton-induced fission of ${}^{238}\mathrm{U}$ have been determined to be 19.4(27) s and 8.2(13) s, respectively, using a gas-jet coupled on-line isotope separator. The present half-lives and those of the recently identified nuclei ${}^{159}\mathrm{Pm},$ ${}^{161}\mathrm{Sm},$ ${}^{165}\mathrm{Gd},$ ${}^{166}\mathrm{Tb}$ were compared with theoretical predictions. The recent calculation by the gross theory with the new one-particle strength functions shows quite good agreement with the experimental half-lives. Excited states of the daughter nuclides ${}^{167}\mathrm{Dy}$ and ${}^{168}\mathrm{Dy}$ have been established for the first time. Level energies of the first ${2}^{+}$ states in even-even Dy isotopes were found to show an irregular behavior at ${}^{164}\mathrm{Dy}$ and increasing deformation toward the neutron midshell around $N\ensuremath{\approx}104$.

We previously reported that ceramide released from glycosphingolipids (GSLs) by endoglycoceramidase was directly metabolized to GSLs, and thus the content of GSLs was constantly maintained in B16 melanoma cells (Ito, M., and Komori, H. (1996) J. Biol. Chem. 271, 12655-12660). In this study, the metabolism of ceramide released from sphingomyelin (SM) by bacterial sphingomyelinase (SMase) was examined using B16 cells and their GSL-deficient mutant counterpart GM95 cells. Treatment of B16 melanoma cells with bacterial SMase effectively hydrolyzed SM on the plasma membrane. Under these conditions, NeuAcalpha2,3Galbeta1, 4Glcbeta1,1ceramide was significantly increased. Interestingly, UDP-glucose:ceramide glucosyltransferase-1 (GlcT-1) activity and GSL synthesis, but not SM synthesis or sphingosine generation, were found to be up-regulated by SMase treatment. The up-regulation of GSL synthesis seemed to occur at both the transcriptional and post-translational steps of GlcT-1 synthesis. Accumulation of ceramide by bacterial SMase was much higher in GM95 cells than in the parental cells. When the enzyme was removed from the culture medium, the intracellular ceramide level in B16 cells, but not that in the mutant cells, normalized. No rapid restoration of SM in either of the cell lines was observed after removal of the enzyme. SMase treatment strongly inhibited DNA synthesis in GM95 cells but not that in B16 cells. In the presence of D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol, an inhibitor of GlcT-1, SMase treatment markedly increased the ceramide content and thus inhibited DNA synthesis in B16 cells. Our study provides the first evidence that GlcT-1 functions to regulate the level of intracellular ceramide by glycosylation of the ceramide when it is present in excess.

A non-destructive and on-line diffusion tracing in Li ionic conductors has been demonstrated. As the tracer, the pulsed beam of the short-lived α-emitting radioisotope of 8Li was implanted into a typical Li ionic conductor LiGa. By analyzing the time-dependent yields of the α-particles measured in coincident with the repetition cycle of the beam, the tracer diffusion coefficients were extracted with a good accuracy. The ordering of the Li vacancies in the Li-deficient β phase of LiGa was observed for the first time in terms of the Li diffusion by the present method.

Ceramide glucosyltransferase (glucosylceramide synthase, GlcT-1, EC 2.4.1.80) catalyzes the first step in glycosphingolipid synthesis, the transfer of glucose from UDP-glucose to ceramide. The product, glucosylceramide, serves as a core structure for over 300 species of glycosphingolipids. The enzyme is a key regulatory factor controlling intracellular levels of ceramide and glycosphingolipids. We have cloned the gene for mouse ceramide glucosyltransferase,Ugcg.The gene spans approximately 32 kb and is composed of 9 exons and 8 introns. The promoter region was found to lack TATA and CAAT boxes but contains Sp1 binding sites, which are indicators of typical house-keeping genes. In addition to these general transcription factor binding sites, the motifs for AhR, NF-κB, AP-2 and GATA-1 binding sites were found.

Ceramide glucosyltransferase (EC 2.4.1.80) catalyzes the first glycosylation step of glycosphingolipid (GSL) synthesis, the transfer of glucose from UDP-Glucose to hydrophobic ceramide and generate glucosylceramide (GlcCer). We have cloned mouse ceramide glucosyltransferase cDNA from a brain cDNA library by PCR based homology cloning. The nucleotide sequence determination revealed that mouse ceramide glucosyltransferase cDNA encodes 394 amino acids with a calculated molecular mass of 45 kDa. The amino acid sequence of mouse ceramide glucosyltransferase showed 98% identity with the human sequence. Homology searches against currently available databases identified three homologous proteins in Caenorhabditis elegans and one homologous protein in Cyanobacteria. Highly conserved sequences of ceramide glucosyltransferases and the homologs among a wide variety of organisms suggest biological significance of the lipid glucosylation system.

It is shown, for the first time, that hydrogen can be produced photoelectrocatalytically from natural seawater under sunlight at ambient temperature without the assistance of externally applied bias potential by the use of a materially optimized thin film transparent titania photocatalyst. A SUPEC (single unit photoelectrocatalysis) cell, combining the thin film photocatalyst and an electrocatalyst into one sheet, is constructed to produce hydrogen at a rate of 0.4 liter h −1 given a 1 m 2 cross-sectional area of sunlight irradiation on the photocatalyst. The photocatalyst remains stable and active in natural seawater. Also, quantum efficiency for photon-to-current conversion, measured in natural seawater under a constant photon irradiation and without bias potential, reached 54% as the wavelength was varied systematically. Both the hydrogen production rate and the quantum efficiency are at the same level as in the case with a typical electrolyte such as potassium bicarbonate solution. Seawater is a natural electrolyte solution which can be used without modification for photocatalytic water decomposition.