Stability for non-hyperbolic fixed points of scalar difference equations

AbstractWe give some new criteria to determine the stability of a non-hyperbolic fixed point of the scalar difference equation xn+1=f(xn)(n=0,1,2,…), where xn∈R and f is a sufficient smooth function. Our results are based on higher order derivative f(k)(x¯) at a fixed point of x¯

Free energy molecular dynamics simulations of pulsed-laser-irradiated SiO2: Si–Si bond formation in a matrix of SiO2

Recent experiments have shown that pure Si structures in a matrix of SiO2 can be formed by electron excitation techniques, with appealing applications in nanotechnology. Our ab initio simulations provide an insight into the underlying mechanism, showing that electron excitations weaken Si–O bonds in SiO2, dislodge O atoms and allow Si dangling bonds to reconstruct in stable Si–Si structures below the melting temperature. Differences in diffusivity of O (fast) and Si (slow) are shown to play a decisive role in the process

雌ラットにおける血中dehydroepiandrosteroneの動態に関する研究

取得学位 : 博士（医学）, 学位授与番号 : 医博乙第1264号,学位授与年月日：平成6年1月19日,学位授与年：199

Explosive crystallization starting from an amorphous-silicon surface region during long pulsed-laser irradiation

A newly developed method of backside time-resolved reflectivity measurement is useful for probing the interface between solid and transient liquid Si. Measurements indicate that explosive crystallization starts very near the Si surface from a highly undercooled liquid Si layer thinner than 3 nm for laser irradiation with long pulses ranging from 65 to 200 ns. During the laser irradiation, surface melt-in continues into fine-grained polycrystalline Si produced by explosive crystallization, followed by solidification of the surface-liquid layer

Solid phase epitaxy of molecular beam deposited amorphous GaAs on Si

Solid phase epitaxial (SPE) crystallization of amorphous GaAs on (100) Si tilted by 4° toward formed by molecular beam deposition (MBD) was first achieved by cw Kr laser irradiation for short durations. The ratio of As to Ga (y/x) in deposited amorphous GaxAsy films was varied from 0.4 to 1.2. During the laser irradiation, movement of the amorphous/crystalline interface was measured using time-resolved optical reflectivity (TROR). It was found from TROR and micro-Raman scattering measurements that hetero-SPE is attained in samples with As/Ga ratios ranging from 0.8 to 1.1 and that the interface roughness is larger than that observed in homo-SPE (e.g., MBD GaAs on GaAs and P+ ion-implanted GaAs)

Hyperfine Structure of the Electron Spin Resonance of Phosphorus-Doped Si Nanocrystals

Electronic states of P donors in Si nanocrystals (nc-Si) embedded in insulating glass matrices have been studied by electron spin resonance. Doping of P donors into nc-Si was demonstrated by the observation of optical absorption in the infrared region due to intraconduction band transitions. P hyperfine structure (hfs) was successfully observed at low temperatures. The observed splitting of the hfs was found to be much larger than that of the bulk Si:P and depended strongly on the size of nc-Si. The observed strong size dependence indicates that the enhancement of the hyperfine splitting is caused by the quantum confinement of P donors in nc-Si

Suppression of Interferon-induced Oligo-2\u27, 5\u27-adenylate Synthetase Induction in Human Hepatoma Cell Line, Li-7

Induction of oligo-2\u27, 5\u27-adenylate synthetase (2-5AS) activity by interferon (IFN) was investigated in a human hepatoma cell line, Li-7 cells. Little induction of 2-5AS activity by IFN was demonstrated in Li-7 cells in comparison with other types of cell lines including Ramos, NC-37, FL, Co-3. Furthermore, failure to induce 2-5AS was much clearer in old-cultured cells. Cell growth inhibition by IFN was demonstrated in only high titers of IFN (>10? IU/ml), in which the enzyme had one hundred fold higher activity than that of untreated cells. Poor induction of 2-5AS was in part the result of some inhibitor presented in cellular extracts of Li-7 cells and the decreased level of 2-5AS mRNA transcription

Feasibility of Endoscopy-Assisted Laparoscopic Full-Thickness Resection for Superficial Duodenal Neoplasms

Background. Superficial duodenal neoplasms (SDNs) are a challenging target in the digestive tract. Surgical resection is invasive, and it is difficult to determine the site and extent of the lesion from outside the intestine and resect it locally. Endoscopic submucosal dissection (ESD) has scarcely been utilized in the treatment of duodenal tumors because of technical difficulties and possible delayed perforation due to the action of digestive juices. Thus, no standard treatments for SDNs have been established. To challenge this issue, we elaborated endoscopy-assisted laparoscopic full-thickness resection (EALFTR) and analyzed its feasibility and safety. Methods. Twenty-four SDNs in 22 consecutive patients treated by EALFTR between January 2011 and July 2012 were analyzed retrospectively. Results. All lesions were removed en bloc. The lateral and vertical margins of the specimens were negative for tumor cells in all cases. The mean sizes of the resected specimens and lesions were 28.9 mm (SD ± 10.5) and 13.3 mm (SD ± 11.6), respectively. The mean operation time and intraoperative estimated blood loss were 133 min (SD ± 45.2) and 16 ml (SD ± 21.1), respectively. Anastomotic leakage occurred in three patients (13.6%) postoperatively, but all were minor leakage and recovered conservatively. Anastomotic stenosis or bleeding did not occur. Conclusions. EALFTR can be a safe and minimally invasive treatment option for SDNs. However, the number of cases in this study was small, and further accumulations of cases and investigation are necessary

Distribution and abundance of squids caught in surface gillnets in the subartic Pacific, 1977-1981

Memoirs of the Faculty of Fisheries. Vol. 30 No. 1/2 (1983