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The development of holographic data storage is expected as a next-generation large-capacity memory. The recording scheme of spatial quadrature amplitude modulated (SQAM) signal, whose amplitude and phase are individually modulated with multi-levels, is a promising technique to improve the recording density of the memory. In this paper, we propose a method to simultaneously record multiple SQAM signals with different angles in the holographic memory. We also propose a method to detect the amplitude and phase value of the SQAM signal from the interference intensity distribution formed by the two SQAM signals selectively reproduced from the memory. We evaluate the decoding accuracy when the multiple SQAM signals generated by the interleaved phase method are recorded and the two signals are extracted and readout numerically. We also give experimental result as proof of principle of the decoding process. In the end, we analyze the accuracy against multiple number of SQAM signals on a recording page. [ABSTRACT FROM AUTHOR]

Taste buds endure extreme changes in temperature, pH, osmolarity, so on. Even though taste bud cells are replaced in a short span, they contribute to consistent taste reception. Each taste bud consists of about 50 cells whose networks are assumed to process taste information, at least preliminarily. In this article, we describe a neural network model inspired by the taste bud cells of mice. It consists of two layers. In the first layer, the chemical stimulus is transduced into an irregular spike train. The synchronization of the output impulses is induced by the irregular spike train at the second layer. These results show that the intensity of the chemical stimulus is encoded as the degree of the synchronization of output impulses. The present algorithms for signal processing result in a robust chemical-sensing system. [ABSTRACT FROM AUTHOR]

Spike-timing-dependent synaptic plasticity (STDP) is a simple and effective learning rule for sequence learning. However, synapses being subject to STDP rules are readily influenced in noisy circumstances because synaptic conductances are modified by pre- and postsynaptic spikes elicited within a few tens of milliseconds, regardless of whether those spikes convey information or not. Noisy firing existing everywhere in the brain may induce irrelevant enhancement of synaptic connections through STDP rules and would result in uncertain memory encoding and obscure memory patterns. We will here show that the LTD windows of the STDP rules enable robust sequence learning amid background noise in cooperation with a large signal transmission delay between neurons and a theta rhythm, using a network model of the entorhinal cortex layer II with entorhinal-hippocampal loop connections. The important element of the present model for robust sequence learning amid background noise is the symmetric STDP rule having LTD windows on both sides of the LTP window, in addition to the loop connections having a large signal transmission delay and the theta rhythm pacing activities of stellate cells. Above all, the LTD window in the range of positive spike-timing is important to prevent influences of noise with the progress of sequence learning. [ABSTRACT FROM AUTHOR]

We investigated successive firing of the stellate cells within a theta cycle, which replicates the phase coding of place information, using a network model of the entorhinal cortex layer II with loop connections. Layer II of the entorhinal cortex (ECII) sends signals to the hippocampus, and the hippocampus sends signals back to layer V of the entorhinal cortex (ECV). In addition to this major pathway, projection from ECV to ECII also exists. It is, therefore, inferred that reverberation activity readily appears if projections from ECV to ECII are potentiated. The frequency of the reverberation would be in a gamma range because it takes signals 20–30 ms to go around the entorhinal-hippocampal loop circuits. On the other hand, it has been suggested that ECII is a theta rhythm generator. If the reverberation activity appears in the entorhinal-hippocampal loop circuits, gamma oscillation would be superimposed on a theta rhythm in ECII like a gamma-theta oscillation. This is a reminiscence of the theta phase coding of place information. In this paper, first, a network model of ECII will be developed in order to reproduce a theta rhythm. Secondly, we will show that loop connections from one stellate cell to the other one are selectively potentiated by afferent signals to ECII. Frequencies of those afferent signals are different, and transmission delay of the loop connections is 20 ms. As a result, stellate cells fire successively within one cycle of the theta rhythm. This resembles gamma-theta oscillation underlying the phase coding. Our model also replicates the phase precession of stellate cell firing within a cycle of subthreshold oscillation (theta rhythm). [ABSTRACT FROM AUTHOR]

Background: Few studies have specifically examined the effects of n-3 polyunsaturated fatty acids (PUFAs) on intestinal water and ion secretion in ulcerative colitis (UC). The aim of this study was to examine the contribution of prostaglandins (PGs) and leukotrienes (LTs) to mucosal secretion in intestines with UC and to evaluate the effect of dietary n-3 PUFAs on diarrhea in UC.Methods: We measured the short-circuit current (Isc), using the Ussing chamber method, and fatty acid composition in the colonic mucosa of rats with dextran sulfate sodium (DSS)-induced experimental colitis. The DSS-treated rats were fed either a perilla oil-enriched diet (perilla group) or a soybean oil-enriched diet (soybean group); a control group did not undergo DSS administration.Results: The bradykinin-stimulated DeltaIsc in the soybean and perilla groups was significantly higher than that in the control group. The mucosal level of arachidonic acid in the perilla group was significantly lower than that in the soybean group. The mucosal levels of alpha-linolenic acid and EPA in the perilla group were significantly higher than those in the soybean group. The bradykinin-stimulated DeltaIsc was significantly suppressed after pretreatment with indomethacin in both the soybean and perilla groups, and was also significantly reduced in both groups after pretreatment with AA861. The suppression of bradykinin-stimulated DeltaIsc by the addition of AA861 was significantly higher in the perilla group than in the soybean group.Conclusions: Our results suggest that supplementation with alpha-linolenic acid, in combination with a lipoxygenase inhibitor, could suppress the increase in Cl- secretion in patients with UC. [ABSTRACT FROM AUTHOR]

Few studies have specifically examined the effects of n-3 polyunsaturated fatty acids (PUFAs) on intestinal water and ion secretion in ulcerative colitis (UC). The aim of this study was to examine the contribution of prostaglandins (PGs) and leukotrienes (LTs) to mucosal secretion in intestines with UC and to evaluate the effect of dietary n-3 PUFAs on diarrhea in UC. We measured the short-circuit current (Isc), using the Ussing chamber method, and fatty acid composition in the colonic mucosa of rats with dextran sulfate sodium (DSS)-induced experimental colitis. The DSS-treated rats were fed either a perilla oil-enriched diet (perilla group) or a soybean oil-enriched diet (soybean group); a control group did not undergo DSS administration. The bradykinin-stimulated ΔIsc in the soybean and perilla groups was significantly higher than that in the control group. The mucosal level of arachidonic acid in the perilla group was significantly lower than that in the soybean group. The mucosal levels of α-linolenic acid and EPA in the perilla group were significantly higher than those in the soybean group. The bradykinin-stimulated ΔIsc was significantly suppressed after pretreatment with indomethacin in both the soybean and perilla groups, and was also significantly reduced in both groups after pretreatment with AA861. The suppression of bradykinin-stimulated ΔIsc by the addition of AA861 was significantly higher in the perilla group than in the soybean group. Our results suggest that supplementation with α-linolenic acid, in combination with a lipoxygenase inhibitor, could suppress the increase in Cl- secretion in patients with UC. [ABSTRACT FROM AUTHOR]

Substantial genomic and functional evidence from primary tumors and cell lines indicates that a consistent region of distal chromosome 1p is deleted in a sizable proportion of human neuroblastomas, suggesting that this region contains one or more tumor suppressor genes. To determine systematically and precisely the location and extent of 1p deletion in neuroblastomas, we performed allelic loss studies of 737 primary neuroblastomas and genotype analysis of 46 neuroblastoma cell lines. Together, the results defined a single region within 1p36.3 that was consistently deleted in 25%of tumors and 87%of cell lines. Two neuroblastoma patients had constitutional deletions of distal 1p36 that overlapped the tumor-defined region. The tumor- and constitutionally-derived deletions together defined a smallest region of consistent deletion (SRD) between D1S2795 and D1S253. The 1p36.3 SRD was deleted in all but one of the 184 tumors with 1p deletion. Physical mapping and DNA sequencing determined that the SRD minimally spans an estimated 729?kb. Genomic content and sequence analysis of the SRD identified 15 characterized, nine uncharacterized, and six predicted genes in the region. The RNA expression profiles of 21 of the genes were investigated in a variety of normal tissues. The SHREW1 and KCNAB2 genes both had tissue-restricted expression patterns, including expression in the nervous system. In addition, a novel gene (CHD5) with strong homology to proteins involved in chromatin remodeling was expressed mainly in neural tissues. Together, these results suggest that one or more genes involved in neuroblastoma tumorigenesis or tumor progression are likely contained within this region.Oncogene (2005) 24, 2684-2694. doi:10.1038/sj.onc.1208306 Published online 27 December 2004 [ABSTRACT FROM AUTHOR]

Deals with a study which proposed an all-fiber optical add-drop multiplexer (ADM) using a pair of fiber grating couplers (FGC). All-fiber optical ADM using a pair of FGC; Numerical and experimental results; Conclusions.

Proposes an amplified spontaneous emission reduction filter using cascaded optical fiber grating couplers for the repeater in wavelength division multiplexing transmission systems. Experimental results; Theoretical prediction of required optical fiber grating coupler characteristics; Conclusions.

A case of co-occurrence of a mucoepidermoid carcinoma (MEC) and a squamous cell carcinoma (SCC) in the esophagus is described. The present patient was a 61-year-old man who underwent a curative esophagectomy with a regional lymph node dissection for a MEC in the lower esophagus and a SCC near the esophagogastric junction. The two lesions were endoscopically and histologically divided by a normal esophageal mucosa. The MEC of the esophagus consisted of SCC cells and signet-ring cells, and a mucin product and carcinoembryonic antigen, which were found at high levels in the blood serum before surgery, were detected histochemically in the signet-ring cells. The follow-up survey of the patients with esophageal MEC previously reported in Japan showed that most of the patients died of either local recurrence or widespread metastasis after treatment; the overall 5-year survival rate was 24.4% in the total 25 cases, and 27.7% in the 22 resected cases. However, 6 patients who died of therapeutic complications were included among these patients; furthermore, the 5-year survival rate after surgery was 29.2% in the patients treated over the last decade (1989–1998). We expect that the clinical outcome of patients treated for esophageal MEC will therefore improve in the future. [ABSTRACT FROM AUTHOR]

OBJECTIVE: α-Fetoprotein (AFP)-producing gastric cancer has been associated with a poor prognosis. In the present study, the cell proliferation, apoptosis, and angiogenesis of this cancer were studied histochemically to determine its malignant potential. METHODS: Tissue samples were taken from four patients with AFP-producing gastric cancer and 26 patients with AFP-negative gastric cancer. Cell proliferation was evaluated by Ki-67 immunostaining, and the Ki-67 labeling index (LI) was determined. Apoptosis was studied by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling method, and the apoptotic index was determined. Angiogenesis was evaluated by measuring the microvessel density using factor VIII immunostaining, and immunostainings for vascular endothelial growth factor and thymidine phosphorylase were performed. RESULTS: The Ki-67 LI of the AFP-producing gastric cancers was significantly higher than that of the AFP-negative gastric cancers (p < 0.01). The apoptotic index of the AFP-producing gastric cancers was significantly lower than that of the AFP-negative gastric cancers (p < 0.01), The microvessel density of the AFP-producing gastric cancers was significantly higher than that of the AFP-negative gastric cancers (p < 0.01). Vascular endothelial growth factor expression was observed in all four of the AFP-producing gastric cancers, whereas thymidine phosphorylase was not expressed in any of the AFP-producing gastric cancers. CONCLUSIONS: These results suggest that AFP-producing gastric cancers have high malignant potential (high proliferative activity, weak apoptosis, and rich neovascularization) compared with that of AFP-negative gastric cancers. These biological characteristics of AFP-producing gastric cancer reflect the aggressive behavior and the poor prognosis of patients with this type of cancer. [ABSTRACT FROM AUTHOR]

We present some results of a magnetic flux-tube soliton propagating along a current loop surrounded by a weakly ionized plasma, by using a 3-D Neutral-MHD simulation code. When the velocity of mass flows outside the current loop exceeds about 0.6υA, the magnetic pulse behaves as an isolated string wave which is called a curved soliton, propagating with a velocity less than that one of exterior mass flow. The propagation speed of the magnetic flux-tube soliton is studied by changing the intensity of the electric current along the flux tube, which usually cannot be observed directly. It is found that the soliton speed decreases proportionally to the increment of the electric current, and the speed is independent of the direction of the electric current. We can estimate the current intensity inside a magnetic flux-tube soliton by observations of the soliton speed and the external plasma flow velocity. These results should be compared with recent high-resolution observations of moving magnetic features (MMFs) observed near sunspots. [ABSTRACT FROM AUTHOR]

Retroperitoneal venous hemangioma is a very rare condition. Only two cases have been reported in the English literature. We report the case of a 28-yr-old man with a retroperitoneal venous hemangioma who underwent surgical resection. Preoperative magnetic resonance imaging revealed a retroperitoneal tumor with low signal intensity on the T1-weighted image and high signal intensity on the T2-weighted image, typical of hemangiomas. In addition, it showed a partial interruption of the muscle layer surrounding the tumor. Intraoperative findings showed a large, reddish brown retroperitoneal mass with an ill defined capsule firmly attached to the muscular tissue surrounding the tumor. Retroperitoneal hemangioma is rare and is almost always of the cavernous type. Although accurate pre- and intraoperative diagnosis of retroperitoneal venous hemangiomas is difficult, magnetic resonance imaging and the presence of a firm attachment to the muscles may be helpful for the important diagnostic findings of this disease. [ABSTRACT FROM AUTHOR]