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AbstractTight focusing with very small f-numbers is necessary to achieve the highest at-focus irradiances. However, tight focusing imposes strong demands on precise target positioning in-focus to achieve the highest on-target irradiance. We describe several near-infrared, visible, ultraviolet and soft and hard X-ray diagnostics employed in a ∼1022W/cm2laser–plasma experiment. We used nearly 10 J total energy femtosecond laser pulses focused into an approximately 1.3-μm focal spot on 5–20 μm thick stainless-steel targets. We discuss the applicability of these diagnostics to determine the best in-focus target position with approximately 5 μm accuracy (i.e., around half of the short Rayleigh length) and show that several diagnostics (in particular, 3 $\omega$ reflection and on-axis hard X-rays) can ensure this accuracy. We demonstrated target positioning within several micrometers from the focus, ensuring over 80% of the ideal peak laser intensity on-target. Our approach is relatively fast (it requires 10–20 laser shots) and does not rely on the coincidence of low-power and high-power focal planes.

Surface reconstruction from point clouds generated by laser scanning technology has become a fundamental task in many fields of geosciences, such as robotics, computer vision, digital photogrammetry, computational geometry, digital building modelling, forest planning and operational activities. Point clouds produced by laser scanning, however, are limited due to the occurrence of occlusions, multiple reflectance and noise, and off-surface points (outliers), thus necessitating the need for robust fitting techniques. In this contribution, a fast, non-iterativeand data invariantalgebraic algorithm with constant O(1) complexity that fits planes to point clouds in the total least squares sense using Gaussian-type error distribution is proposed. The maximum likelihood estimator method is used, resulting in a multivariate polynomial system that is solved in an algebraic way. It is shown that for plane fitting when datasets are affected heavily by outliers, the proposed algebraic method can be embedded intothe framework of robust methods like the Danish or the RANdom SAmple Consensus methods and computed in parallelto provide rigorous algebraic fitting with significantly reduced running times. Compared to the embedded traditional singular value decomposition and principal component analysis approaches, the performance of the proposed algebraic algorithm demonstrated its efficiency on both synthetic data and real laser-scanned measurements. The evaluation of a symbolic algebraic formula is practically independent of the values of its coefficients; however, the computation of the coefficients depends on the complexity of the data. Since the main advantage of the symbolic solution is its non-requirement of numerical iteration, the data complexity will have weak influence on the speed-up. The novelty of the proposed method is the use of algebraic technique in a robust plane fitting algorithm that could be applied to remote sensing data analysis/delineation/classification. In general, the method could be applied to most plane fitting problems in the geoscience field.

It is shown that the production of X-ray emission spectra in the interaction of high-intensity laser radiation with cluster targets may be affected by the bichromatic oscillating electric field arising from the generation of the second harmonic of laser radiation. A technique is proposed for diagnosing harmonic generation in laser - cluster interactions using the spectral line profiles of multiply charged helium ions. The efficiency of second harmonic generation at a laser intensity of 3 x 1018 W cm-2 is shown to amount to about 2%.

The V-notch Charpy testing for laser beam welds (LBWs) sometimes presents fracture path deviation(FPD) into a base metal with lower strength at service temperature. The main effort of this work is to propose a damage model to simulate ductile fracture path depending on the feature of LBWs such as strength mismatch and a width of a weld metal. Static loading tests for a Charpy V-notch specimen reveals details of the FPD process; the ductile crack directly starts to deviate from the notch root into a softer base metal in purely shear-slip mode over full thickness of the specimen. The subsequent ductile crack extends toward the base metal in shear-slip mode along with shallow dimples. The proposed damage model can predict the occurrence of fracture path deviation in shear-slip mode for the Charpy specimen with a notch in narrow bead used for experiment.

The characteristics of a sol-gel derived Pb(Zr,TiO)3capacitor with polycrystalline SrRuO3electrodes deposited by reactive sputtering were evaluated. A single perovskite phase Pb(Zr,Ti)O3film with columnar grain structure was formed on SrRuO3substrates since nucleation of Pb(Zr,Ti)O3took place at the interface with SrRuO3. A Pb(Zr,Ti)O3capacitor with top and bottom SrRuO3electrodes exhibited good polarization reversibility. Remanent polarization at 5.0 V was 20.8 µ c/cm2. No degradation of remanent polarization was observed up to switching cycles of 1x1010. Polycrystalline SrRuO3thin film is expected to be a good candidate for the electrode material of Pb(Zr,Ti)O3capacitors.

Fasciolaspp. were collected from naturally infected cattle at a local abattoir of Khanh Hoa province, Vietnam, for morphological and genetic investigations. Microscopic examination detected no sperm cells in the seminal vesicles, suggesting a parthenogenetic reproduction of the flukes. Analyses of sequences from the first and second internal transcribed spacers (ITS1 and ITS2) of the ribosomal RNA revealed that 13 out of 16 isolates were of Fasciola giganticatype, whereas three isolates presented a hybrid sequence from F. giganticaand Fasciola hepatica. Interestingly, all the mitochondrial sequences (partial COI and NDI) were of F. giganticatype, suggesting that the maternal lineage of the hybrid form is from F. gigantica. No intra-sequence variation was detected.

An experimental and theoretical study has been carried out of the ablation of a solid insulator with a wide band gap (LiF) under the action of ultrashort laser pulses of the UV range, obtained in a free-electron laser (pulse width τ_L=0.3ps, photon energy ħω_L=20.2eV), and the soft X-ray region, obtained in a silver-plasma laser (τ_L=7ps, ħω_L=89.3eV). A comparison is made of the results obtained on the two laser systems. It is shown that the ablation threshold is about the same for both lasers. A theory is presented that explains the weak growth of the ablation mass with increasing surface energy density of the laser radiation (the fluence) in the case of X-ray lasers as a result of the transition from spallation close to the ablation threshold to evaporative ablation at high fluence values.

This paper presents the experimental investigation of laser-driven proton acceleration using a table top Ti:Sapphire laser system interacting with the thin-foil targets during the course of medical application of the laser-driven proton beam. The proton beam with maximum energy of upto 14~MeV is generated in 60 TW mode. The number of protons at ~10 MeV is estimated to be over 105proton/sr/MeV/shot with beam having half divergence angle of 5~degree. If 10 Hz operation is assumed 2 Gy dose is possible to irradiate during 10 min onto a ~1 mm tumor just under the skin. In contrast to the previous condition of our apparatus with which we demonstrated the DNA double-strand breaking by irradiating the laser-driven proton beam onto the human cancer cells in-vitrotest, the result reported here has significant meaning in the sense that pre-clinical in-vivotest can be started by irradiating the laser-driven proton beam onto the skin of the mouse, which is unavoidable step before the real radiation therapy.

Surface electronic structures of n-GaP(001) and p-InP(001) with and without sulfur treatment have been studied by X-ray photoelectron spectroscopy (XPS), synchrotron radiation photoemission spectroscopy (SRPES), and inverse photoemission spectroscopy (IPES). The Fermi level (EF) of a clean n-GaP(001)-(2x4) surface is found to be pinned at 0.2 eV above the valence band maximum (VBM), suggesting that the surface electronic bands are bent upward. XPS spectra reveal that the EF is moved to 2.3 eV above the VBM by the sulfur treatment, implying that the sulfur-treated surface has flat bands. The IPES result shows that empty dangling bond states on Ga atoms at the surface are located at the conduction band minimum (CBM) and they disappeared with the treatment. SRPES spectra of a clean p-InP(001)-(2x4) surface indicate that the EF is located at 0.3 eV above the VBM and surface states due to phosphorus atoms are at –0.9 eV below the EF. The result implies that the surface has almost flat bands. Empty dangling bond states on In atoms at the clean surface are found to be located at the conduction band edge. Surface states due to the In-S bonds are found at –3.5 eV below the EF for the sulfur-treated surface. The sulfur treatment of the clean surface leads to a little shift (0.1 –0.2 eV) of the EF and to considerable reduction of the empty states in the band gap. A type conversion of p- to n- is not observed in the present work. This is discussed in terms of the thickness of a sulfide layer.

The paper is devoted to experimental and theoretical studies of ablation of condensed matter by optical (OL), extreme ultraviolet (EUV) and X-ray lasers (XRL). Results obtained at two different XRL are compared. The first XRL is collision Ag-plasma laser with pulse duration L= 7 ps and energy of quanta hv=89.3 eV, while the second one is EUV free electron laser (EUV-FEL) and has parameters L= 0.3 ps and energy of quanta 20.2 eV. It is shown that ablation thresholds for these XRL at LiF dielectric are approximately the same. A theory is presented which explains slow growth of ablated mass with fluence in case of XRL as a result of transition from spallative ablation near threshold to evaporative ablation at high fluencies. It is found that the metal irradiated by short pulse of OL remains in elastic state even in high shear stresses. Material strength of aluminum at very high deformation rates V/V ~ 109s-1is defined.

An old surface analytical method, appearance potential spectroscopy (APS), which can probe empty electronic states, is briefly reviewed, since it has an ability to be applied to studying nanostructures. Although the theoretical calculation of the APS spectra including a two-electron process is not much simpler than that of x-ray absorption spectroscopy (XAS) spectra with a one-electron process, measurements of the APS spectra are simpler than those of the XAS ones. A careful interpretation of the spectra would lead to a characteristic and simple surface chemical analysis.

We report that it seems to be necessary to select Bologna University mobility model for accurate transient phenomenon analysis of SiC-SBD under the condition of forward surge current because the maximum of the temperature inside SiC-SBD arises up to above 425 K. Other mobility models seem to be mostly inadequate because they are corresponding to the experimental condition under the temperature below 425 K.

The effectiveness of a visual birdscarer, the Peaceful Pyramid®, relative to a much-cheaper eye-spot balloon was investigated experimentally in two vineyards in Canterbury, New Zealand. Monitoring of bird damage to natural bunches of Riesling grapes within vineyard blocks showed that the rate of starling (Sturnus vulgaris) damage to the crop was reduced significantly by the balloon relative to pyramid and control plots. Nevertheless, after 24 days of monitoring, birds in the balloon plot had damaged 75% of the grapes, respectively (cf. 84% in the pyramid plot). In a second trial, clusters of table grapes were attached to vineyard wire at a Lincoln vineyard. The balloon and pyramid both reduced bird damage to clusters within 15 m of the device, but had no measurable effect on clusters further away. We conclude that neither device would provide growers with any economically significant reduction in grape damage. This study highlights the importance of undertaking quantitative assessments of the numerous bird-scaring technologies presently available to growers.

The deployment of wireless LAN and other communication media, such as 3G cellular, is proceeding rapidly. In the near future, multiple WLAN carriers, together with 3G cellular and other communication carriers, will provide their services in a complementary fashion. Furthermore, next-generation mobile phones, which may use voice and data services simultaneously, will connect these networks. In the present article we design and evaluate a new network architecture that ensures appropriate QoS for next-generation mobile phones. Through performance evaluations, we show that our architecture improves QoS for voice communication.

Free-radical polymerization of dibenzofulvene (DBF) was carried out under various conditions. The radical polymerization proceeded exclusively in vinyl fashion without isomerization of the growing radical or aromatic substitution by the initiator fragment. The polymerization was highly conformation-specific (stereospecific), giving a polymer with a π-stacked conformation in which the main-chain C−C bonds are nearly all trans and the side-chain fluorene moieties are stacked on top of each other. The conformation specificity (stereospecificity) of the DBF radical polymerization was almost similar to that in the anionic polymerization although the radical polymerization products appeared to have a small amount of irregular, defective conformation incorporated into the mostly π-stacked chain. The conformation specificity was affected by the initial monomer concentration and reaction temperature. This observation was explained by a proposed mechanism where two types of the growing radicals having different conformations mediate the polymerization. The poly(DBF) obtained by the radical polymerization showed lower fluorescent intensity and higher solubility possibly due to a small amount of conformational defects.

Abstract Algebra, in particular commutative algebra, is applied here to provide a general unified solution to nonlinear systems of equations encountered in geodesy. Starting with the “Abelian group”, the “polynomial ring” is defined and used to form generators of ideals. By applying Buchberger or polynomial resultant algorithms, these generators are reduced to simple structures often comprising a univariate polynomial in one of the unknowns. The advantage of the proposed unified approach is that it provides exact solutions to geodetic nonlinear systems of equations without the traditional requirements of linearization, iterations or approximate starting values. The commutative algebraic approach therefore alleviates the need for isolated exact solutions to various geodetic nonlinear systems of equations. The procedure is applied to GPS meteorology to compute refraction angles, and Helmert’s one-to-one mapping of topographical points onto the reference ellipsoid.

Abstract. The scale factor of a superconducting gravimeter (SG) at the Esashi Earth Tides Station, Japan, was revised by repeating co-located absolute gravity measurements with an FG5 gravimeter. Although the calibration results from the absolute gravimeter (AG) show an apparent secular change in the scale factor of the SG (0.4% for the period 1993–2002), the relative scale factors, which are determined by tidal analysis with the response method, indicate that it has changed by no more than 0.01% during the above period. If the mean scale factor over the 10 years is adopted, a value of -56.082±0.029 µGal/V (1 µGal =10-8 m s-2) is obtained, which is about 0.4% smaller than that used in the global geodynamics project (GGP) database. Based on this newly determined scale factor, the tidal gravity factors at Esashi have been re-estimated. The observed tidal factors, corrected for the ocean tide effects with recent models, indicate that the theoretical gravity factors for an inelastic Earth model are more consistent with the observations than are those for an elastic model.

High-resolution K-shell spectra of a plasma created by superintense laser irradiation of micron-sized Ar clusters have been measured with an intensity above 1019 W/cm2 and a pulse duration of 30 fs. The total photon flux of 2 × 108 photons/pulse was achieved for Heα1 resonant line of Ar (λ = 3.9491 Å, 3.14 keV). In parallel with X-ray measurements, energy distributions of emitted ions have been measured. The multiply charged ions with kinetic energies up to 800 keV were observed. It is found that hot electrons produced by high contrast laser pulses allow the isochoric heating of clusters and shift the ion balance toward the higher charge states, which enhances both the X-ray line yield of the He-like argon ion and the ion kinetic energy.

Two new oleanane-type triterpenoids (1 and 2), together with two known compounds, 6β-hydroxy-3-oxo-lup-20(29)-en-28-oic acid (3) and 3,11-dioxoolean-12-en-28-oic acid (4), were isolated from the stem bark of Liquidamber styraciflua. The structures of 1 and 2 were determined to be 25-acetoxy-3α-hydroxyolean-12-en-28-oic acid (1) and 3α,25-dihydroxyolean-12-en-28-oic acid (2) on the basis of spectroscopic methods and chemical conversion. Compound 1 showed strong cytotoxicity against a disease-oriented panel of 39 human cancer cell lines, although compounds 2, 3, and 4 showed weaker activity compared to 1.

Background & Aims: Interleukin-6 (IL-6) regulates immune response and inflammation. We carried out a pilot placebo-controlled study to investigate the efficacy, pharmacokinetics, and safety of MRA, a humanized monoclonal antibody to IL-6 receptor, in patients with active Crohn's disease. Methods: Thirty-six patients with active Crohn's disease (Crohn's Disease Activity Index [CDAI] >=150) were randomly assigned to receive biweekly intravenous infusion of either placebo, MRA, or MRA/placebo alternately for 12 weeks at a dose of 8 mg/kg. The study's primary end point was a clinical response rate that was defined as a reduction of CDAI >=70. Results: At the final evaluation, 80% of the patients (8 of 10) given biweekly MRA had a clinical response as compared with 31% of the placebo-treated patients (4 of 13; P = 0.019). Twenty percent of the patients (2 of 10) on this regimen went into remission (CDAI <150), as compared with 0% of the placebo-treated patients (0 of 13). The clinical response rate of the every-4-week regimen was 42% (5 of 12). The serum concentrations of MRA were detected at 2 weeks after every infusion, at which time acute phase responses were completely suppressed; however, they were not suppressed at 4 weeks. Endoscopic and histologic examination showed no difference between MRA and placebo groups. The incidence of adverse events was similar in all the groups. Conclusions: This is the first clinical trial of humanized anti-IL-6 receptor monoclonal antibody in Crohn's disease. A biweekly 8 mg/kg infusion of MRA was well tolerated, normalized the acute-phase responses, and suggests a clinical effect in active Crohn's disease.

The study aimed to determine the association between cytotoxin-associated gene product (CagA), serum gastrin and pepsinogen levels in Japanese children infected with Helicobacter pylori.Three hundred children were enrolled in the study. H. pyloriinfection was assessed using an enzyme-linked immunosorbent assay, and CagA status was assessed using immunoblotting. Serum gastrin and pepsinogen concentrations were measured by radioimmunoassay. H. pyloriseroprevalence was 12.3% (37/300) and CagA status was identified in 28/37 H. pylori-seropositive children (75.7%). Serum pepsinogen I and II levels were significantly higher in CagA-seropositive than CagA-seronegative children with H. pyloriinfection. There was no significant relationship between CagA seropositivity and serum gastrin levels. In conclusion, CagA status has a significant impact on serum pepsinogen levels, possibly through enhanced gastric mucosal inflammation.

An inhibitor of factor Xa (fXa), the m-substituted benzamidine AXC1578 (1a), was structurally modified with the aim of increasing its potency. In particular, pyruvic acid and propionic acid substituents were incorporated into the P1 benzamidine moiety to introduce a favorable interaction with the oxy-anion hole in the catalytic triad region of fXa. This strategy was based on computational docking studies using the extracted active site of fXa. The validity of the computational model was supported by the acquisition of X-ray crystal structures of the 1a−trypsin and 3b−trypsin complexes (the homology around the active sites of fXa and trypsin is high). The above modifications significantly increased the inhibitory activity toward fXa, whereas the high selectivity for fXa versus thrombin was maintained or enhanced. Compounds 3b, 3c, 3e, and 4b are considered to be potential lead compounds for the development of orally active anticoagulant drugs because they demonstrated potent activity when administered orally to cynomolgus monkeys.

Abstract.:  The latest gravimetric geoid model for Japan, JGEOID2000, was successfully combined with the nationwide net of GPS at benchmarks, yielding a new hybrid geoid model for Japan, GSIGEO2000. The least-squares collocation (LSC) method was applied as an interpolation for fitting JGEOID2000 to the GPS/leveling geoid undulations. The GPS/leveling geoid undulation data were reanalyzed in advance, in terms of three-dimensional positions from GPS and orthometric heights from leveling. The new hybrid geoid model is, therefore, compatible with the new Japanese geodetic reference frame. GSIGEO2000 was evaluated internally and independently and the precision was estimated at 4 cm throughout nearly the whole region.

Abstract: It is known that metallurgical phenomena such as recovery, recrystallization, grain growth, and aging are due to the diffusion of constituent atoms in materials. The heat treatments that cause these phenomena are conducted defining both time and temperature. In the diffusion process, it is the diffusion distance that is defined by both time and temperature. Therefore, the authors surmise that there must be a relationship between the change of material properties as a result of heat treatment and the diffusion distances of constituent atoms. Under this assumption, diffusion distances of constituent atoms at recovery, recrystallization, grain growth, and aging in aluminum and copper alloys were examined. As a result, it was found that these phenomena take place at the fixed diffusion distances peculiar to the materials and phenomena. Therefore, the relationship between time and temperature was decided in terms of the fixed diffusion distances. In this respect, empirically used “normalized annealing time” turns out to mean the diffusion distance.

ABSTRACTT-705 (6-fluoro-3-hydroxy-2-pyrazinecarboxamide) has been found to have potent and selective inhibitory activity against influenza virus. In an in vitro plaque reduction assay, T-705 showed potent inhibitory activity against influenza A, B, and C viruses, with 50% inhibitory concentrations (IC50s) of 0.013 to 0.48 μg/ml, while it showed no cytotoxicity at concentrations up to 1,000 μg/ml in Madin-Darby canine kidney cells. The selectivity index for influenza virus was more than 2,000. It was also active against a neuraminidase inhibitor-resistant virus and some amantadine-resistant viruses. T-705 showed weak activity against non-influenza virus RNA viruses, with the IC50s being higher for non-influenza virus RNA viruses than for influenza virus, and it had no activity against DNA viruses. Orally administered T-705 at 100 mg/kg of body weight/day (four times a day) for 5 days significantly reduced the mean pulmonary virus yields and the rate of mortality in mice infected with influenza virus A/PR/8/34 (3 × 102PFU). These results suggest that T-705 may be a compound that is useful and highly selective against influenza virus infections and that has a mode of action different from those of commercially available drugs, such as amantadine, rimantadine, and neuraminidase inhibitors.

Abstract: Background. The problem of whether surgical or conservative treatment is indicated for ruptured hepatocellular carcinoma (HCC) has not been analyzed from the viewpoint of long-term development of hepatitis viral infection from liver fibrosis to liver cirrhosis. Although transcatheter arterial embolization (TAE) for hemostasis followed by two-stage hepatectomy has been established as the best treatment for ruptured HCC, there still remain difficulties in the treatment of some patients. Methods. Twelve patients with ruptured HCC who were surgically or conservatively treated were retrospectively analyzed in terms of modality of treatment, liver function, extension of HCC, complications, survival rate, and cause of death. Results. Tumor rupture can occur either in the early phase or in the terminal phase during the development from liver fibrosis to liver cirrhosis, while tumor rupture occurs at the advanced stage in terms of HCC extension. TAE for emergent hemostasis or prevention of re-bleeding was performed in ten patients, while TAE was contraindicated in one patient and emergent laparotomy for hemostasis was performed in one patient. In four patients, elective extended surgical resection was performed, because liver function was evaluated as clinical stage 1 according to the General rules for the clinical and pathological study of primary liver cancer of the Liver Cancer Study Group of Japan. In seven patients, conservative or medical treat-ment was selected, because liver function was evaluated as poor. The surgically treated group, who could tolerate extensive operation, survived longer than the conservatively treated group. Conclusions. While TAE remains the best method to employ for hemostasis, it still has limitations. Hence, we should be mindful of other possible modalities for hemostasis and their outcomes. Rupture of HCC at an early phase in the development of liver fibrosis is a good indication for elective surgical treatment and should be distinguished from rupture in the terminal phase of liver cirrhosis, which should be treated conservatively. Although elective surgical treatment can be performed in selected patients, tumor size and location of HCC, in addition to liver function, should be taken into consideration.

A photoelectron spectrum of an acrylonitrile (AN:CH2&dbd;CHCN) trimer anion, (AN)3^-, produced by electron impact on an acrylonitrile cluster was measured, and was compared with that of a molecular anion of 1,3,5-cyclohexanetricarbonitrile (c-HTCN) in the triequatorial form, which was first synthesized in the present experiment. A comparison of the vertical detachment energies of (AN)3^- and the molecular anion lead us to conclude that (AN)3^- is assigned as one of the stereoisomers (diaxial form) of c-HTCN (−) on the basis of our previous studies refs 13, 14, and 20−22 [Tsukuda, T.; Kondow, T. J. Chem. Phys. 1991, 95, 6989. Tsukuda, T.; Kondow, T. J. Am. Chem. Soc. 1994, 116, 9555. Ichihashi, M.; Tsukuda, T.; Nonose, S.; Kondow, T. J. Phys. Chem. 1995, 99, 17354. Fukuda, Y.; Tsukuda, T.; Terasaki, A.; Kondow, T. Chem. Phys. Lett. 1995, 242, 121. Fukuda, Y.; Tsukuda, T.; Terasaki, A.; Kondow, T. Chem. Phys. Lett. 1996, 260, 423.].

Deficiency of micronutrients, especially selenium, is common in critically ill patients. We investigated the micronutrient status (selenium, zinc, copper and manganese) and glutathione peroxidase (GSH-Px) activity in 30 tube-fed patients and 21 hospitalized non-tube-fed control patients. Serum levels of selenium, copper and manganese in tube-fed patients were significantly lower than in control patients (selenium: 4.85 ± 1.38 μg/dl versus 8.67 ± 1.45 μg/dl; copper: 44.7 ± 36.9 μg/dl versus 92.1 ± 21.2 μg/dl; manganese 0.59 ± 0.41 μg/dl versus 1.52 ± 0.59 μg/dl). However, zinc and log GSH-Px in the serum were similar in the two groups. Serum selenium concentration correlated with the daily intake of selenium in tube-fed patients, but zinc, copper and manganese concentrations did not correlate with the daily intake of the respective trace elements in tube-fed patients. Blood GSH-Px activity correlated positively with serum selenium concentrations in the control patients, but not in tube-fed patients. These results demonstrate that selenium content of enteral feed appears to be insufficient to maintain normal serum levels in elderly bedridden patients. Our findings emphasize the importance of monitoring micronutrient status in patients on enteral feeding to avoid trace element deficiencies

The paper focuses on the interaction mechanism caused by anionic polymer dispersants in dense silicon nitride and silicon carbide suspensions. An atomic force microscope (AFM) was used to determine the relationship between the macroscopic suspension viscosity and the microscopic structure adsorbing of a polymer dispersant at the solid/liquid interface. The surface interactions within the suspensions were analyzed under various dispersant pH values and additive conditions. The addition of an anionic polymer dispersant decreased the viscosity of silicon nitride and silicon carbide suspension and increased the electrosteric repulsive force on the non-oxide surface in solution at pH > 6, which was the isoelectric point of the materials. Based on the above results, we estimated the adsorption mechanism of anionic polymer dispersants on each solid surface in solution under relatively high pH conditions.

Adsorption and decomposition of t-butylphosphine (TBP: (CH3)3CPH2) on a GaP(001)-(2×1) surface have been studied by low-energy electron diffraction (LEED), high-resolution electron energy loss spectroscopy (HREELS), and temperature programmed desorption (TPD). It is found that most of TBP is partially dissociated into H and (CH3)3CPH at 350K. The t-butyl radical and isobutylene are evolved from the surface at about 350–450 and 450–550K, respectively. The activation energy for the radical was estimated to be about 101kJ/mol. The result obtained, here, is different from that on a GaP(001)-(2×4) surface. The decomposition mechanism for TBP on the surface is discussed.

We synthesized the novel seco cyclopropa[c]pyrrolo[3,2-e]indole (CPI) bisalkylators and evaluated their antitumor activity. Among these derivatives, 11a (AT-760), in which the two seco 3-methoxycarbonyl-2-trifluoromethyl CPI (MCTFCPI) moieties are connected with a 3,3‘-(1,4-phenylene)bisacryloyl group, was found to exhibit more potent cytotoxicity and antitumor activity against HeLaS3 human uterine cervix carcinoma cells and Colon 26 adenocarcinoma cells, respectively, than 8 (bizelesin, U-77,779). It also appeared that compound 11a exhibits improved in vivo efficacy in the human colon CX-1 model when compared to either compound 8 or mitomycin C (MMC). Efficacious doses for 11a were found to be 2-fold lower than those for 8.

Objectives: Outbreaks of hepatitis A virus (HAV) infection in haemophiliacs have been reported from many countries. The aim of this study was to determine the prevalence of hepatitis A virus antibody (HAVAb) in Japanese haemophiliacs. Methods: Sixty-seven male haemophiliacs were recruited for this study of HAV infection. We also compared the rate of HAV infection with that of human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis G virus (HGV). Results: Fifteen of 67 haemophiliacs (22.4%) were positive for HAVAb. Prevalence of HAVAb was significantly higher in haemophiliacs than in Japanese normal subjects previously reported (P= 0.0001). Age, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin and prevalence of HIV, HCV, and HGV were not statisticallydifferent between HAVAb positive and HAVAb negative haemophiliacs. We suggest that the use of clotting factorconcentrates is closely associated with HAV infection, but HAV infection does not have an effect on clinical course. Conclusions: Administration of clotting factor concentrates may increase risk of HAV infection in haemophiliacs. Copyright 2001 The British Infection Society