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PDF file, 1193K, Figure S1. Snail+ tumor cells frequently metastasize into bone marrow. Figure S2. Differentiation activity of the specific subpopulations isolated from the Snail+ tumor-stimulated BMCs. Figure S3. The Snail+ tumor-induced MSCs promote tumor metastatic seeding into bone. Figure S4. Increase of fstl1 and its receptor dip2a mRNA expressions in Snail+ tumor cells. Figure S5. FSTL1-knockdown suppresses metastatic seeding of human tumor cells into bone. Figure S6. FSTL1-induced cancer bone metastasis mechanism.

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Kouichi Murakami,1 Emi Inayama,1 Yukiko Itoh,1 Shoji Tuchiya,1 Masashi Iwasaki,2 Nobuko Tamura,1 Toshihiko Suzuki,3 Noriko Iwai,1 Junji Utino,4 Motoyuki Masai,4 Daiji Nagayama,5,6 Kohji Shirai4,6 1Seijinaki Mihama Narita Clinic, Narita City, Chiba, 286-0041, Japan; 2Seijinkai Mihama Katori Clinic, Katori City, Chiba, 287-0041, Japan; 3Seijinkai Mihama Sakura Clinic, Sakura City, Chiba, 285-0841, Japan; 4Seijinkai Mihama Hospital, Chiba City, Chiba, 261-0013, Japan; 5Nagayama Clinic, Oyama City, Tochigi, 323-0032, Japan; 6Sakura Hospital, School of Medicine Toho University, Sakura City, Chiba, 285-8741, JapanCorrespondence: Daiji NagayamaNagayama Clinic, 2-12-22, Tenjin-Cho, Oyama City, Tochigi, 323-0032, JapanTel/Fax +81-285-22-0219Email deverlast96071@gmail.comAim: Mortality rate of maintenance hemodialysis patients is known to be high. Cardio-ankle vascular index (CAVI) is an index reflecting the proper stiffness of the arterial tree from the origin of the aorta to the ankle. We aimed to clarify the utility of CAVI as a predictor of mortality in hemodialysis patients. The roles of age and nutritional conditions on survival were also examined.Methods: We followed 242 patients undergoing hemodialysis for 6 consecutive years. Data from 209 patients (mean age was 60 ± 11 years) excluding those with ankle-brachial index < 0.90 were then analyzed. CAVI and heart to ankle pulse wave velocity (haPWV) were measured using Vasera 1500.Results: Thirty-eight hemodialysis patients who died during the 6-year period had higher age, cardiothoracic ratio (CTR), CAVI, and haPWV, and lower diastolic blood pressure, albumin, phosphate, and calcium phosphate product. The Kaplan–Meier curves for cumulative survival among the tertile groups showed that the mortality rate was higher in the highest tertile (T3) compared to T1/T2 for both CAVI and haPWV. Receiver operating characteristic (ROC) analysis revealed that CAVI had better discriminatory power for all-cause mortality compared to haPWV. In the Cox-proportional hazards analyses, 1 SD increase in both parameters contributed independently to all-cause mortality [CAVI: HR 1.595 (95% CI 1.108– 2.297), haPWV: HR 1.695 (95% CI 1.185– 2.425)], as well as age and CTR. Both parameters above the cut-offs estimated in the ROC analysis (CAVI ≥ 9.2, haPWV ≥ 8.9) also had independent contributions to mortality.Conclusion: Through the 6 consecutive years of follow-up in 209 HD patients, increased CAVI might represent a major modifiable risk factor for all-cause mortality. Further research is needed to examine whether CAVI-lowering interventions contribute to improved prognosis.Keywords: hemodialysis patient, mortality, cardio-ankle vascular index, phosphorus

The number of limit cycles for three dimensional Lotka–Volterra competitive systems is an open problem. Recently, we have presented a concrete example with three limit cycles in Zeeman’s class 27 [6]. In this paper, we present a concrete example with three limit cycles which belongs to Zeeman’s class 29. We explicitly give the critical parameter values such that the interior equilibrium is an exact unstable weak focus of order two. Also we verify that the system is permanent. This implies that there can exist three limit cycles around the interior equilibrium under suitable perturbations. We actually generate multiple limit cycles, and confirm them by numerical simulation. In addition, we present some other examples with three limit cycles in Zeeman’s class 27.

The number of limit cycles for three dimensional Lotka–Volterra systems is an open problem. Recently, Yu et al. (2016) constructed some examples with the possibility of the existence of four limit cycles. Unfortunately, multiple limit cycles are not visible by numerical simulations, because all of them are very close to the interior equilibrium and extremely small. We present a concrete example with multiple limit cycles for three dimensional Lotka–Volterra systems which we can confirm them by numerical simulations. First we prepare the modified formula to compute coefficients of the normal form for the generalized Hopf bifurcation. Applying this formula to three dimensional Lotka–Volterra competitive systems with the aid of the computer algebra system, we derive the critical parameter values explicitly such that the interior equilibrium is exactly an unstable weak focus. Also we show that the heteroclinic cycle on the boundary of R + 3 is repelling. This implies that there exists a stable limit cycle by the Poincare–Bendixson theorem. Then, adding some suitable perturbations to parameters, we generate additional two limit cycles near the interior equilibrium by the generalized Hopf bifurcation. Finally we confirm that there exist three limit cycles by numerical simulations.

Thymine DNA glycosylase (TDG) is a base excision repair (BER) enzyme, which is implicated in correction of deamination-induced DNA mismatches, the DNA demethylation process and regulation of gene expression. Because of these pivotal roles associated, it is crucial to elucidate how the TDG functions are appropriately regulated in vivo. Here, we present evidence that the TDG protein undergoes degradation upon various types of DNA damage, including ultraviolet light (UV). The UV-induced degradation of TDG was dependent on proficiency in nucleotide excision repair and on CRL4CDT2 -mediated ubiquitination that requires a physical interaction between TDG and DNA polymerase clamp PCNA. Using the Tdg-deficient mouse embryonic fibroblasts, we found that ectopic expression of TDG compromised cellular survival after UV irradiation and repair of UV-induced DNA lesions. These negative effects on cellular UV responses were alleviated by introducing mutations in TDG that impaired its BER function. The expression of TDG induced a large-scale alteration in the gene expression profile independently of its DNA glycosylase activity, whereas a subset of genes was affected by the catalytic activity of TDG. Our results indicate the presence of BER-dependent and BER-independent functions of TDG, which are involved in regulation of cellular DNA damage responses and gene expression patterns.

FSCE focused on resist materials and coordinate correction technology for FPD mask and carried out research on underlying technology. The results we obtained are reported.

To improve the light-scattering capacity of transparent conductive oxide (TCO) films without increasing in surface roughness, we formed a stacked nanoparticle layers of ZnO (NP-ZnO) and TiO2 (NP-TiO2), which serve as light-scattering and surface-modifying layers, respectively, between the glass substrate and low-resistive TCO layers. The stacked TCO/NP/glass (NP-TCO) substrate indicated strong light-scattering capacity, with a relatively low surface root mean roughness of approximately 10nm. In addition, the haze value of NP-TCO substrates increased with an increase in the component particle diameter of the underlying NP-ZnO layers from about 20% (33nm) to 40% (96nm) at a wavelength of 550nm. [doi:10.2320/matertrans.M2014208]

Bone metastasis greatly deteriorates the quality of life in patients with cancer. Although mechanisms have been widely investigated, the relationship between cancer bone metastasis and antitumor immunity in the host has been much less studied. Here, we report a novel mechanism of bone metastasis mediated by FSTL1, a follistatin-like glycoprotein secreted by Snail+ tumor cells, which metastasize frequently to bone. We found that FSTL1 plays a dual role in bone metastasis—in one way by mediating tumor cell invasion and bone tropism but also in a second way by expanding a population of pluripotent mesenchymal stem-like CD45−ALCAM+ cells derived from bone marrow. CD45−ALCAM+ cells induced bone metastasis de novo, but they also generated CD8low T cells with weak CTL activity in the periphery, which also promoted bone metastasis in an indirect manner. RNA interference-mediated attenuation of FSTL1 in tumor cells prevented bone metastasis along with the parallel increase in ALCAM+ cells and CD8low T cells. These effects were accompanied by heightened antitumor immune responses in vitro and in vivo. In clinical specimens of advanced breast cancer, ALCAM+ cells increased with FSTL1 positivity in tumor tissues, but not in adjacent normal tissues, consistent with a causal connection between these molecules. Our findings define FSTL1 as an attractive candidate therapeutic target to prevent or treat bone metastasis, which remains a major challenge in patients with cancer. Cancer Res; 73(20); 6185–93. ©2013 AACR.

In doped Si nanowires (SiNWs) boron (B) atoms segregate to the surface oxide layers during thermal oxidation, while phosphorus (P) atoms preferentially pile up in Si crystalline regions close to the Si/SiO2 interface. Here we report on micro-Raman scattering and electron spin resonance (ESR) measurements showing that B atoms can be stabilized at the crystalline Si core region in codped SiNWs with average diameters of 20–30 nm because of the strong interaction between B and P atoms during thermal oxidation below 800 °C. Theoretical calculation clearly demonstrated the effect of B–P pairing, which can stabilize the B atoms in the Si side. In the B–P pairing configuration, dopant passivation—beyond simple compensation—occurs, making the impurities electrically inactive.

We investigated the prevalence of occult hepatitis B virus (HBV) infection in Japanese chronic hemodialysis patients. Hemodialysis patients (n = 1041) were screened for occult HBV. The presence of hepatitis B surface antigen (HBsAg), hepatitis B surface antibody, and hepatitis B core antibody (anti-HBc) was determined by various chemiluminescent immunoassays. HBV-DNA was quantified in patients positive for anti-HBc using quantitative real-time polymerase chain reaction. Among the 1041 patients, six (0.6%) were HBsAg-positive and 218 (20.9%) were anti-HBc-positive. All HBsAg-positive patients also tested positive for the presence of HBV DNA. Of 212 HBsAg-negative and anti-HBc-positive patients, three were positive for HBV DNA. Our study showed that the prevalence of occult HBV infection in chronic hemodialysis patients from eastern Japan was 0.3%.

Recrystallization of silicon nanowires (SiNWs) after ion implantation strongly depends on the ion doses and species. Full amorphization by high-dose implantation induces polycrystal structures in SiNWs even after high-temperature annealing, with this tendency more pronounced for heavy ions. Hot-implantation techniques dramatically suppress polycrystallization in SiNWs, resulting in reversion to the original single-crystal structures and consequently high reactivation rate of dopant atoms. In this study, the chemical bonding states and electrical activities of implanted boron and phosphorus atoms were evaluated by Raman scattering and electron spin resonance, demonstrating the formation of p- and n-type SiNWs.

本研究では，pH刺激応答性ポリマーの1つとして，pH 6.5付近で相変化を示す性質を持つPoly{4-[2-(vinyloxy)-ethoxy]-benzoic acid} : Poly(VEBA)sを用いて，各種金属イオンに対する分離挙動を検討した．その結果，いくつかの特異的な金属捕集特性が確認された．その中で特に希土類元素（レアアース）について特徴的な結果が得られ，pH変化とろ過操作を用いて，レアアースを分離・回収できるシステムを開発した．回収率は検討した16種類のレアアースについてすべて90～100％ であった．また，水酸化ナトリウム水溶液を用いてPoly(VEBA)sを再溶解させることで，フィルター上で回収したPoly(VEBA)sと金属の分離が可能であった．Poly(VEBA)sを再び回収することでPoly(VEBA)sのリサイクルも可能である．本システムは，有機溶媒を使用しない全水系システムであるため環境や生体に対する安全性も高いと言える．

*1 Institute of Applied Physics, University of Tsukuba, 1-1-1 Ten'nodai, Tsukuba, Ibaraki 305-8573, bk200820379@s.bk.tsukuba.ac.jp *2 Graduate School of Information Sciences and Electrical Engineering, Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395,Japan *3 Department of Health Sciences, School of Medicine, Kyushu University, 3-1-1 Maidashi, Fukuoka 812-8582, Japan *4 Electronics and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki305-8565, Japan

Silica glass can be ablated using focused laser plasma soft X-rays. The ablation technique enables us to fabricate trenches with a width as narrow as 50 nm. In the present paper, we have investigated the nano-ablation process. The soft X-ray irradiation causes a silica surface broken into almost atomic species. Ionic species have kinetic energies higher than that gained by heating to the boiling point. We measured the ablation depth as a function of the soft X-ray fluence. The depth analysis revealed that soft X-rays are absorbed in a silica surface with an effective absorption depth of 10 nm. The result indicates that the energy density of the soft X-rays per unit volume at the threshold fluence is comparable to that required for breaking silica glass into atomic species. Further, the results suggest that ablation occurs before diffusion of absorbed energy into the surrounding region. In addition to energy absorption, repulsive forces between ionic species may cause ablation of the silica surface by soft X-ray irradiation. These properties of soft X-ray ablation may make possible the nano-ablation of silica glass. © 2011 Wiley Periodicals, Inc. Electron Comm Jpn, 94(9): 30–35, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.10354

We are investigating the micromachining of silica glass using extreme ultraviolet (EUV) light from laser-produced plasma (LPP). The present investigation deals with the ablation using EUV light of around 13.5 nm and 11 nm generated in laser-produced Sn plasma and Xe plasma, respectively. CO2 laser and Nd:YAG lasers were used as pump lasers. The EUV radiation was focused on the surface of silica glass through the meshed mask using an ellipsoidal mirror coated with gold film. The results showed that the silica glass was successfully ablated by EUV light from the Nd:YAG-LPP. The maximum ablation rate was 42 nm per shot for 11-nm light, and 25 nm per shot for 13.5-nm light. On the other hand, EUV radiation from the CO2-LPP did not ablate the silica glass. This is presumably caused by the lower EUV irradiation intensity due to the long pulse duration of the CO2 laser.

We review recent works on 1) an isotope effect of penetration of Hydrogen(H) and Deuterium(D) into Silicon through Si/SiO2 interface and 2) H effects for Si nanostructures, as well as summary of hydrogen states in crystal Si. In particular, a new filtering effect of H and D isotope atoms was found for penetration process into crystal silicon (Si) through the interface between a Si and SiO2 native oxide layer. More H atoms are introduced into Si than D for mixing gases. This phenomenon can be tentatively explained in terms of an isotope filtering model of H and D via an intermediate cluster state formed at the interface between the native SiO2 layer and crystal Si. Hydrogen passivation of interface defects is shown to be needed for knowing proper impurity doping effects, and electronic, optical, and magnetic properties in Si nanostructures.

Silica glass can be ablated using focused laser plasma soft X-rays. The ablation technique enables us to fabricate trenches with a width as narrow as 50 nm. In the present paper, we have investigated the nano-ablation process. The soft X-ray irradiation cause silica surface broken into almost atomic species. Ionic species have kinetic energies higher than that gained by heating up to the boiling point. We measured ablation depth as a function of soft X-ray fluence. The analysis of the depth revealed that soft X-rays are absorbed in silica surface with a effective aborption depth of 10 nm. The result leads to that the energy densty of the soft X-rays per unit volume at the threshold fluence is comparable to that required for breaking silica glass into atomic species. Futher, the results suggests that ablation occurs before diffusion of absorbed energy into the surroudning region. In addition to the energy absorption, repulssive force between ionic species may cause ablation of silica surface by soft X-ray irradiation. These properties of soft X-ray ablation may achieve nano-ablation of silica glass.

Boron (B) or phosphorus (P) doped silicon nanowires (SiNWs) were synthesized by laser ablation. Local vibrational modes of B were observed in B-doped SiNWs by micro-Raman scattering measurements at room temperature. Fano broadening due to a coupling between the discrete optical phonon and a continuum of interband hole excitations was also observed in the Si optical phonon peak for B-doped SiNWs. An electron spin resonance signal due to conduction electrons was observed only for P-doped SiNWs. These results prove that B and P atoms were doped in substitutional sites of the crystalline Si core of SiNWs during laser ablation and electrically activated in the sites.

We have investigated nanomachining of inorganic materials using laser plasma soft X-rays. The soft X-rays were generated by irradiating Ta targets with pulsed Nd:YAG laser light. The laser plasma soft X-rays were focused using an ellipsoidal mirror, which is designed so as to focus soft X-rays at around 10 nm efficiently. The focused soft X-rays were incident to the surfaces of inorganic materials such as silica glass, LiF, CaF2, and LiNbO3. It is found that these materials are ablated by soft X-ray irradiation. In particular, silica glass can be ablated at rates of 0.2 to 150 nm/shot, which can be controlled by the intensity of soft X-rays. It is remarkable that silica can be ablated smoothly with a roughness of 1 nm after 10 shots of soft X-ray irradiation at a rate of 50 nm/shot. In order to demonstrate nanomachining of silica glass, we used contact masks on top of silica glass plates fabricated by electron beam lithography technique. The silica glass plates were irradiated with laser plasma soft X-rays through the windows of the contact masks. We found that nanofabrication of trenches with a width of 70 nm was performed clearly. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(4): 45– 51, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10080

The formation and annihilation of hydrogen (H)-related complexes were investigated in boron (B)- or phosphorus (P)-doped Si treated with high concentration of atomic H. The passivation and reactivation process of dopant carriers were significantly different between the p-type and n-type specimens. The differences are explained by the stable sites of the H atoms in the p-type and n-type specimens and, in turn, by the formation of H-related defects: i.e., H multiple trapping centers are formed by bond-breaking due to H atoms only in p-type B-doped Si. The formation of such defects retards the reactivation of B dopants by annealing.

Hydrogen passivation of phosphorus (P) donors and defects in P-doped silicon nanowires (SiNWs) were investigated by electron spin resonance (ESR) at 4.2 K. P doping was performed during the synthesis of SiNWs by laser ablation. Phosphorus doping into substitutional sites of crystalline Si in SiNWs was demonstrated by detection of an ESR signal with a g-value of 1.998, which corresponds to conduction electrons in crystalline Si. ESR signals related to defects in surface oxide layer and at interface between surface oxide and crystalline Si core were observed. These P donors and the defects were partially passivated by hydrogen and oxygen atoms as seen in bulk Si.

We compute the direction of the Neimark–Sacker bifurcation for a discrete-time predator–prey model. This problem is presented in Y. Kuznetsov's book. Moreover, we give the asymptotic approximation of the invariant curve.

The effect of phonon confinement and impurity doping in silicon nanowires (SiNWs) synthesized by laser ablation were investigated. The diameter of SiNWs was controlled by the synthesis parameters during laser ablation and the subsequent thermal oxidation. Thermal oxidation increases the thickness of the SiNWs’ surface oxide layer, resulting in a decrease in their crystalline Si core diameter. This effect causes a downshift and asymmetric broadening of the Si optical phonon peak due to phonon confinement. Boron doping was also performed during the growth of SiNWs. Local vibrational modes of boron (B) in silicon nanowires (SiNWs) synthesized by laser ablation were observed at about 618 and 640 cm–1 by Raman scattering measurements. Fano broadening due to coupling between discrete optical phonons and the continuum of interband hole excitations was also observed in the Si optical phonon peak. These results prove that B atoms were doped in the SiNWs.

We have investigated the fabrication of two types of Er-doped silicon oxide films. The films were prepared by ablating a Si target covered with a thin Er metal layer, by Nd:YAG laser light at 50 mJ/pulse in 40 Torr O2 gas. After depositing the Er-dispersed SiOx (x ~ 1.4) films, the films were annealed in Ar gas. We found that Er-doped films deposited at (a) 4 J/cm2 and (b) 100 J/cm2 have the optimum annealing temperatures of 600°C and 900°C, respectively. Furthermore, we found that Er-doped films deposited at 4 J/cm2 exhibit much more intense light emission at 1.5 µm than those deposited at 100 J/cm2. For the Er-doped films deposited at 100 J/cm2, it is evident that electron-hole pairs are generated in Si nanocrystallites precipitated in a SiO2 film and that recombination energy is transfered to Er3+ ions that emit 1.5 µm light, via the lowest luminescent state in Si nanocrystallites.

We have investigated micromachining of a variety of materials by irradiation with laser plasma soft X-rays (LPSXs) at around 10 nm. The pulsed LPSXs were generated by irradiation of a Ta target in a vacuum chamber with Nd:YAG laser light at 532 nm, with a pulse duration of 7 ns, at a fluence of ~104 J/cm2. The LPSXs were focused on the surfaces of samples using an ellipsoidal mirror that is designed so that LPSXs at around 10 nm are focused efficiently. We found that quartz glass plates are ablated by LPSX irradiation at a typical rate of 48 nm/shot. Furthermore, the ablated regions have smooth surfaces with a roughness less than 10 nm after 10 shots of LPSX irradiation. It is demonstrated that quartz glass is machined with a lateral resolution higher than 100 nm. In addition to quartz glass, the LPSX processing can be applied to micromachining of a variety of materials such as Pyrex, CaF2, LiF, LiNbO3, Si and silicone.

We have investigated nanomachining of inorganic materials using laser plasma soft X-rays. The soft X-ray was generated by irradiating Ta targets with pulsed Nd:YAG laser light. The laser plasma soft X-rays were focused using an ellipsoidal mirror, which is designed so as to focus soft X-rays at around 10 nm efficiently. The focused soft X-rays were incident to the surfaces of inorganic materials such as silica glass, LiF, CaF2 and LiNbO3. It is found that these materials are ablated by soft X-ray irradiation. In particular, silica glass can be ablated at rates of 0.2-150 nm/shot, which can be controlled by the intensity of soft X-rays. It is remarkable that silica can be ablated smoothly with a roughness of 1 nm after 10 shots of soft X-ray irradiation at a rate of 50 nm/shot. In order to demonstrate nanomachining of silica glass, we used contact masks on top of silica glass plates fabricated by electron beam lithography technique. The silica glass plates were irradiated with laser plasma soft X-rays through the windows of the contact masks. We found that nanofabrication of trenches with a width of 70 nm are performed clearly.

The formation of hydrogen (H)-related complexes was investigated in boron (B)-doped Si treated with high concentration of H. The isotope shifts of H-related Raman peaks by replacement of H to deuterium and 10B to 11B clearly showed the formation of the B–H complexes in which H directly bonds to B in Si. The results of the resistivity measurements suggested that the B acceptors are passivated via the formation of the B–H complexes, as well as the well-known passivation center in B-doped Si, namely, H–B passivation center.

The phonon confinement effect was investigated by Raman measurements for Si nanowires (SiNWs) synthesized by laser ablation of a Si target with nickel (Ni) catalyst and for SiNWs thermally oxidized at 700–1000 °C. The Si optical phonon peak for SiNWs, unlike that for bulk Si, showed a downshift and an asymmetric broadening. Thermal oxidation caused a further downshift and broadening. These phenomena can be explained by the phonon confinement effect due to the decrease in the diameter of the Si core of the SiNWs. It was additionally found that excess oxidation caused an upshift of the optical phonon peak due to compressive stress.

Recent experiments have shown that Si nanostructures can be formed in a matrix Of SiO2 by laser-pulse irradiation, with appealing applications in nanotechnology. We hereby present first principles simulations that provide a microscopic insight into the underlying mechanism, showing how electron excitations weaken Si-O bonds in SiO2, dislodging O atoms and allowing the formation of stable Si-Si structures below the melting temperature. (c) 2006 Elsevier B.V. All rights reserved.

We have investigated ablation of silica glass using pulsed laser plasma soft X-rays. For generating a plasma that emits pulsed soft X-rays, a Ta target was irradiated with focused 532 nm Nd:YAG laser light with a pulse duration of 7 ns at a fluence of 10 4 J/cm 2 . The soft X-rays were focused on the surfaces of silica glass using a Au-coated ellipsoidal mirror. The energy density of the soft X-rays can be roughly estimated to be 0.1 J/cm 2 , which is sufficiently enough for heating silica glass beyond the boiling point. We found that silica glass is smoothly ablated at 40 nm/shot. The processes induced by X-ray irradiation have been discussed based on transient-absorption measurements after X-ray irradiation.

Effects of amorphous carbon (a-C) thin film coating over carbon nanotubes (CNTs) on the field emission characteristics have been studied. Large-area surface-wave plasma (SWP) device was used both for growth of multi-wall CNTs on Ni-evaporated Si substrate and for deposition of a-C thin layer over CNTs. Field emission characteristics of the a-C film-coated CNTs prepared with different CVD durations were investigated. Experimental results show that the emission performance was significantly improved by coating a-C film typically with a thickness of 0.6–1 μm, that is, the ignition voltage for electron emission was reduced from 240 V for the sample of CNTs only to 110 V for that of CNTs deposited with a-C film during 60 min. The surface morphology has been also studied using the field emission type scanning electron microscopy (FE-SEM). It was deduced that the reduction of ignition voltage was due to the field enhancement originated from grain shape structures of the surface after a-C film deposition.

Deep lamellar diffraction gratings fabricated by etching a transparent quartz plate are studied using spectroscopic ellipsometry. The rigorous coupled-wave analysis is used to calculate the optical response of the gratings. Three parameters of the rectangular profile are determined by utilizing the least-square method. Detailed investigation of the spectral dependences demonstrates the uniqueness of the solution. Observing the spectral dependences of Wood anomalies suggests that even complicated profiles can be fitted with high authenticity.

Expression of 17beta-hydroxysteroid dehydrogenases (17beta-HSDs) was compared between leiomyoma and myometrium. Cytosolic fractions from leiomyoma homogenate displayed 5-fold higher activity (estrone to estradiol), compared with surrounding myometrium (n = 6, P0.05), whereas microsomal fractions showed no difference. Oxidative activity (estradiol to estrone) did not differ between leiomyoma and myometrium. Levels of mRNA for 17beta-HSDs were then measured using real-time PCR techniques. Among the eight different types of 17beta-HSDs (types 1-5, 7, 8, and 10), type 1 was the only enzyme displaying differential expression between leiomyoma and myometrium. Mean concentration of type 1 17beta-HSD mRNA was 4-fold higher in leiomyoma than in surrounding myometrium (n = 20, P0.05). Type 1 transcript levels correlated significantly with reductive activity in individual samples (n = 6, P0.05). Northern blot analysis of leiomyoma and myometrium tissues detected 2.3- and 1.0-kb transcripts of type 1 enzyme, whereas the major 1.3-kb transcript for 17beta-HSD in placenta-derived JEG-3 cells was not detected. None of the factors increasing mRNA levels for type 1 enzyme in placenta increased mRNA levels in leiomyoma. These results indicate that leiomyoma tissues overexpress type 1 17beta-HSD, resulting in high conversion of estrone to estradiol. In situ expression of type 1 17beta-HSD may play a role in self-supported growth of leiomyoma cells.

We measured real-time spectra of light transmitted through SiO2 specimens during irradiation of amplified ultrashort laser. The real-time spectra exhibit a peak at around 400 nm. The observation and identification of defects were performed by measurements of electron spin resonance (ESR). Both dependences of the peak at around 400 nm on irradiation time and laser power are in good agreement with those of the ESR signal intensity of positively charged oxygen vacancies (E′ center: O3≡Si·). This strong correlation shows that self-trapped excitons are created followed by the formation of the E′ center and finally that of ESR inactive centers, namely, oxygen-deficiency centers (ODCs: O3≡Si-Si≡O3 or O3≡Si:).

The formation mechanism of interstitial H2 in crystalline silicon was investigated by varying the dopant concentration and hydrogenation temperature. At low temperatures such as 125°C, the Raman peak of the interstitial H2 is observed only in heavily doped n-type silicon, suggesting that the formation of H2 includes a metastable donor-hydrogen complex as the precursor and that H2 formation out of two isolated hydrogen atoms is hindered by the Coulombic repulsion between two equally charged atoms at this temperature. At moderate temperatures such as 235°C, the interstitial H2 is formed also for intrinsic and p-type silicon. The absence of the dopant-concentration dependence in p-type silicon indicates that the H2 is created from two hydrogen atoms, at least one of which is neutralized by capturing a thermally excited electron. The formation of the interstitial H2 competes with that of extended planar defects (platelets) at high temperatures such as 305°C.

Er-doped SiO2 thin films including Si nanocrystallites were fabricated by laser ablation of Si targets covered with Er thin films in O2 gas and subsequent thermal annealing. Photoluminescence measurements were performed at temperatures from 10 K to 295 K. The optimum condition was found to be an O2 gas pressure range of 40–50 mTorr. We found that the temperature dependence of Er photoluminescence intensity is governed by power density of excitation laser light. Furthermore, Er photoluminescence is more intense at 295 K than that at 10 K at power densities higher than 480 mW/cm2. These results confirm that Er atoms are excited by energy transfer from photo-excited Si nanocrystallites. On the other hand, photoluminescence intensity of Er-doped Si nanoparticles grown in gas phase gradually decreases with increasing temperature.

Laser ablation using nanosecond pulsed laser light includes some important transient processes during and after laser irradiation. In this paper, the optical absorption of semiconductors and the energy relaxation of excited electrons and holes are briefly described, followed by rapid phase transformation such as transient melting and vaporization which lead to laser ablation of materials. Initial processes of vaporization of solids due to laser ablation have been investigated by several time-resolved measurements. Here we describe a method of time-resolved soft X-ray absorption spectroscopy measurement to show an example of the initial plume produced by laser ablation of Si. This technique gives us information of the time dependence of ejection of Si atoms and Si ions (Si+˜Si4+), and their time-dependent spatial profiles. In addition to nanosecond pulsed laser ablation, characteristics of femtosecond pulsed laser ablation is also discussed, which has been very important to applications.

Several methods for detection of fetal components in maternal blood have been reported. However, few have proven clinically useful for determining the treatment in cases of placental injuries. Here, we report a case of extensive intervillous hematoma diagnosed at 25 weeks of gestation with severe intrauterine growth restriction and oligohydramnios. Marked elevation of fetal DNA levels was observed in maternal blood. Fetal DNA levels decreased after 27 weeks of gestation, concurrent with recovery of fetal growth. We conservatively managed this case until 30 weeks of gestation, when a male infant was delivered. He weighed 508 g and displayed Apgar scores of 7 at 1 minute and 9 at 5 minutes. Histological examination of the placenta revealed intervillous thrombosis without infarction or inflammatory changes. In this case, decreasing fetal DNA levels in maternal plasma correlated with recovery of fetal growth and provided useful information for fetal management as well as insight into the pathogenesis of placental injuries.

We have investigated the chemical reaction of Si nanoparticles with H2 and O2 gases in gas phase after laser ablation of Si targets in Ar and Ne gases. First, we observed time-resolved photoluminescence (PL) from Si nanoparticles in pure Ar gas. The formation of Si nanoparticles begins after the thermalization of Si plasma on a time scale of 1 ms. The energy dissipation of electronic system govern the formation of Si nanoparticles. It was clearly observed that Si nanoparticles grow up to 1.8 ms. Based on the formation dynamics, we observed chemically modified Si nanoparticles using the time-resolved PL method. We found that Si nanoparticles react with hydrogen and oxygen atoms dissociated in the laser plasma. The hydrogenation results in PL at 550 nm and vibronic lines in the wavelength range of 650–800 nm disappear. Oxidation results in PL quenching when O2 partial pressure is higher than 1 Pa. Thus, we have demonstrated chemical modification of Si nanoparticles.

Droplet-free deposition of Si nanoparticle films has been studied applying time-resolved imaging of Si nanoparticles formed by laser ablation of Si targets in Ar gas. We found that Si nanoparticles can be deposited not only on substrates facing to the targets but also on substrates placed beside the target. We further confirmed using a scanning tunneling microscope (STM), Si nanoparticles with sizes of 5–8 nm are deposited on substrates placed beside the target and using a scanning electron microscope (SEM) on the substrates, no droplets are observed.