Nonlinear Compensation of Two-Dimensional Contouring Servomechanism

This paper gives a method of nonlinear compensation for a two-dimensional contouring servomechanism, by which the cornering error, or the transient error at the corner of a figure being traced, is held within given tolerance. The effect of compensation is analyzed by graphical means, using the result of model experiment and the parameters are determined so as to obtain the desirable performance. Stability analysis of the system is also given utilizing the describing function method. The result is applied to an actual automatic flame cutting machine and the practicability is proved

Analysis of the High-Speed Servo-System with an SCR Servo-Amplifier

In this paper we will analyze the high-speed servo-system with an SCR servo-amplifier. The improvement of the system performance is made by stabilizing the system and obtaining a fast response. For these purposes, two nonlinear compensation networks, a nonlinear lowpass filter and a nonlinear compensation with a Zenor diode, are inserted into the feedback loop. The effects of such compensations are investigated by the model experiments and are discussed, considering them as a nonlinear gain adjustment

Analysis of gastrin receptor gene expression in proliferating cells in the neck zone of gastric fundic glands using laser capture microdissection

AbstractGastrin stimulates proliferation of progenitor cells in the neck zone of gastric fundic mucosa. However, whether it directly enhances this proliferation through its receptors remains unclear. We investigated the expression of gastrin receptors in neck zone proliferating cells in rat gastric fundic glands using a reverse transcription polymerase chain reaction (RT-PCR) coupled with laser capture microdissection and in situ RT-PCR. Gastrin receptor expression was identified in c-fos-expressing cells located in the neck zone, and results of the RT-PCR analysis argued against contamination by other cells, such as enterochromaffin-like, parietal or D cells. Supporting this finding, gastrin receptor gene expression was identified in the neck zone as well as base glands by in situ RT-PCR. Therefore, it is suggested that proliferating cells in the neck zone are stimulated directly by gastrin via their gastrin receptors

Analysis of the regional anatomy of the retroesophageal right subclavian artery and surrounding structures

The retroesophageal right subclavian artery (RRSA) is a congenital anomalous branching of the arch of the aorta. Because its incidence is very low, it has not been fully understood how the RRSA develops during embryogenesis, and thus accumulation of observed findings in newly found cases is important to elucidate the etiology of the RRSA. We encountered a case of the RRSA during the course of gross anatomy dissection for medical students. The main findings in the present observations are that (a) the RRSA arose from the right side wall of the arch of the aorta as its last branch; (b) the detected RRSA was directed to the right and upward between the esophagus and vertebral column; (c) the right vertebral artery branched from the RRSA and entered the sixth cervical foramen transversarium; (d) the suprema intercostal artery branched from the costocervical trunk on both sides and its distal branches were distributed to the first and second intercostal spaces; and (e) both sides of bronchial arteries originated from the thoracic aorta. The present study gives further information about the morphological details of the RRSA leading to better understanding of its developmental process.

Nuclear translocation of the cytoplasmic domain of HB-EGF induces gastric cancer invasion

BACKGROUND: Membrane-anchored heparin-binding epidermal growth factor-like growth factor (proHB-EGF) yields soluble HB-EGF, which is an epidermal growth factor receptor (EGFR) ligand, and a carboxy-terminal fragment of HB-EGF (HB-EGF-CTF) after ectodomain shedding. We previously reported that HB-EGF-CTF and unshed proHB-EGF which has the cytoplasmic domain of proHB-EGF (HB-EGF-C), translocate from the plasma membrane to the nucleus and regulate cell cycle after shedding stimuli. However, the significance of nuclear exported HB-EGF-C in human gastric cancer is unclear. METHODS: We investigated the relationship between intracellular localization of HB-EGF-C and clinical outcome in 96 gastric cancer patients treated with gastrectomy. Moreover, we established stable gastric cancer cell lines overexpressing wild-type HB-EGF (wt-HB-EGF) and mutated HB-EGF (HB-EGF-mC), which prevented HB-EGF-C nuclear translocation after shedding. Cell motility between these 2 gastric cancer cell lines was investigated using a transwell invasion assay and a wound healing assay. RESULTS: Of the 96 gastric cancer cases, HB-EGF-C immunoreactivity was detected in both the nucleus and cytoplasm in 19 cases (19.8 %) and in the cytoplasm only in 25 cases (26.0 %). The nuclear immunoreactivity of HB-EGF-C was significantly increased in stage pT3/4 tumors compared with pT1/2 tumors (T1/2 vs. T3/4: 11.1 % vs. 36.4 %, P < 0.01). The growth of wt-HB-EGF- and HB-EGF-mC-expressing cells significantly increased compared with control cells, but the growth of HB-EGF-mC-expressing cells was significantly decreased compared with wt-HB-EGF-expressing cells. Gastric cancer cell invasion obviously increased in wt-HB-EGF-expressing cells, but invasion in HB-EGF-mC-expressing cells showed a slight increase compared with control cells. Moreover, wt-HB-EGF overexpression increased the effectiveness of wound healing, but had no significant effect in HB-EGF-mC-expressing cells. CONCLUSIONS: Both the function of HB-EGF as an EGFR ligand and a novel signal for HB-EGF-C nuclear translocation induce gastric cancer growth, whereas HB-EGF-C nuclear translocation independently plays a critical role in gastric cancer invasion. The present study demonstrated that HB-EGF-C nuclear translocation might be crucial in gastric cancer invasion. HB-EGF-C nuclear translocation may offer a prognostic marker and a new molecular target for gastric cancer therapy

Retinol Supplements Antiviral Action of Interferon in Patients with Chronic Hepatitis C: A Prospective Pilot Study

Sustained virologic response with peg-interferon and ribavirin combination therapy for 48 weeks is still inadequate. Our study examined whether short-term administration of retinol clinically influences the anti-viral activity of interferon early during interferon and ribavirin combination therapy. The control group received 6 MIU of interferon α-2b every day for two weeks and then 3 times a week for 22 weeks intramuscularly plus 600 mg or 800 mg per day of ribavirin orally for 24 weeks. The retinol group, in addition to above treatment, received retinol 30,000 units per day orally for 3 weeks from one week before the start of interferon α-2b plus ribavirin combination therapy. The hepatitis C virus (HCV) RNA negativity rate at 1 week after the end of interferon α-2b and ribavirin combination therapy was 46.7% (28/60) for the retinol group and 31.7% (19/60) for the control group, which was significantly higher for the retinol group. The level of serum HCV RNA in the retinol group was significantly lower at 1 week after beginning treatment as compared to the control group (p<0.01). Furthermore, serum 2,5'AS protein at 1 week after beginning treatment was significantly higher in the retinol group (p = 0.0002). The results suggest that retinol supplement increases the antiviral effect of interferon α-2b plus ribavirin only during the administration of IFN α-2b, ribavirin and retinol in patients with chronic hepatitis C

Feasibility of sliding base isolation for rubble stone masonry buildings in the Himalayan Mountain range

This paper studied the feasibility of a sliding base isolation layer to be used in rubble stone masonry buildings in rural areas in the Himalayan Mountain range to provide robust protection to important building like schools against strong earthquakes. In this paper, we carried out on-site investigations, quasi-static tests, and shaking table tests focusing on constructability as well as isolation performance. From the results of the feasibility study, the combination of styrofoam, concrete slab, and grease was found to be the most feasible to be used as the upper element, the lower element, and the lubricant, respectively, in the sliding isolation layer. The key features of the present sliding base isolation layer are: 1) the use of the materials that exist in rural mountain areas or those that can be easily transported from the neighboring towns and cities and 2) ease of construction and minimal change from the current construction practice. From the shaking table tests, we identified the conditions, e.g., grease amount, grease type, normal stress at the interface, and roughness of concrete slab surface, to achieve dynamic friction coefficients ranging from 0.08 to 0.16, suitable for sliding base isolation