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The slow resonant extraction of a beam in a storage ring is a very well-established technique. Several high-energy physics accelerator facilities around the world are currently using this technique for high-intensity beam operations. As the demand for beam power is constantly growing, extraction efficiency in many cases is becoming a limiting factor. In this report, we discuss a new effective approach to improving the slow extraction efficiency by using configurations of higher multipoles. We will describe this approach, determine optimal multipole configurations, and present the results of simulations to support the proposed recipe. We found that, with the use of higher multipole field content, the extraction efficiency can be improved, and, therefore, the level of prompt and residual radioactivity in the accelerator components and surrounding buildings can be reduced by as much as 40% or more. We also explored manipulating the higher-order effects produced in the pure sextupole configurations for the same purpose and demonstrated that similar results can be achieved by only rearranging the sextupole magnets in the lattice.

Network traffic demands are forecast to increase for the foreseeable future, with the challenge being to meet the demand while maintaining or lowering network costs. Simply increasing capacity will not be sufficient; overall bandwidth utilization also needs to improve. A combination of improved transport capacity through increased spectral efficiency and bit rate along with better network utilization by integrating subchannel electrical grooming into the transmission system will be required. Smarter ways to utilize optical capacity are key since transmission costs have been decreasing slower than grooming and switching costs. Integrated transport and switching can improve the efficiency of the client network using techniques such as port virtualization and transit traffic reduction. The baseline for transport networks will be 100 Gb/s PM-QPSK using 50 GHz channel spacing. Moving from a fixed DWDM channel arrangement to support flexible grid and super channels will allow tighter channel (carrier) spacing and should increase capacity by 30 to 50 percent. For shorter distances higher-order modulation such as 16-QAM can double network capacity. To better optimize network efficiency, an architecture that flexibly combines lower rate (sub-100 Gb/s) clients to form channels (carriers) and then superchannels will be required.

This article overviews requirements, standardization activities, as well as enabling technologies regarding the evolution of the optical transport network with 100 Gigabit Ethernet. Joint requirements raised by the R&D activities of two international carriers are described. Technical assessment for a realistic roadmap is also described.

X-linked dystonia-parkinsonism (XDP) is a movement disorder endemic to the Philippines. The disease locus, DYT3, has been mapped to Xq13.1. In a search for the causative gene, we performed genomic sequencing analysis, followed by expression analysis of XDP brain tissues. We found a disease-specific SVA (short interspersed nuclear element, variable number of tandem repeats, and Alu composite) retrotransposon insertion in an intron of the TATA-binding protein-associated factor 1 gene (TAF1), which encodes the largest component of the TFIID complex, and significantly decreased expression levels of TAF1 and the dopamine receptor D2 gene (DRD2) in the caudate nucleus. We also identified an abnormal pattern of DNA methylation in the retrotransposon in the genome from the patient’s caudate, which could account for decreased expression of TAF1. Our findings suggest that the reduced neuron-specific expression of the TAF1 gene is associated with XDP.

Background: While tumour necrosis factor α (TNF-α) appears to be associated with the development of non-alcoholic steatohepatitis (NASH), its precise role in the pathogenesis of NASH is not well understood. Methods: Male mice deficient in both TNF receptors 1 (TNFR1) and 2 (TNFR2) (TNFRDKO mice) and wild-type mice were fed a methionine and choline deficient (MCD) diet or a control diet for eight weeks, maintaining isoenergetic intake. Results: MCD dietary feeding of TNFRDKO mice for eight weeks resulted in attenuated liver steatosis and fibrosis compared with control wild-type mice. In the liver, the number of activated hepatic Kupffer cells recruited was significantly decreased in TNFRDKO mice after MCD dietary feeding. In addition, hepatic induction of TNF-α, vascular cell adhesion molecule 1, and intracellular adhesion molecule 1 was significantly suppressed in TNFRDKO mice. While in control animals MCD dietary feeding dramatically increased mRNA expression of tissue inhibitor of metalloproteinase 1 (TIMP-1) in both whole liver and hepatic stellate cells, concomitant with enhanced activation of hepatic stellate cells, both factors were significantly lower in TNFRDKO mice. In primary cultures, TNF-α administration enhanced TIMP-1 mRNA expression in activated hepatic stellate cells and suppressed apoptotic induction in activated hepatic stellate cells. Inhibition of TNF induced TIMP-1 upregulation by TIMP-1 specific siRNA reversed the apoptotic suppression seen in hepatic stellate cells. Conclusions: Enhancement of the TNF-α/TNFR mediated signalling pathway via activation of Kupffer cells in an autocrine or paracrine manner may be critically involved in the pathogenesis of liver fibrosis in this NASH animal model.

Nucleotide polymorphisms of the C4 genes were investigated by direct sequencing of seven different homozygous typing cells from the 10IHW panels. Two novel sequences were identified within the C4d region of the C4 genes. Our sequencing analyses extend previous findings suggesting that a recombination hot spot is likely to have occurred between codon positions 1157 and 1186 within the C4d region. The classification of electrophoretically defined C4A and C4B alleles can be further subtyped by sequencing. Because the central major histocompatibility complex region that carries various copies of the C4 gene has been associated with a range of disorders; further analysis at the sequence level within the C4 locus may provide informative genetic markers for the investigation of disease-associated polymorphisms.

Psoriasis vulgaris, a common inflammatory skin disorder, is known to be associated with the HLA-Cw*06 allele. It has been recently suggested by microsatellite mapping that a real susceptible gene for psoriasis resides in the approximately 100-kb genomic region telomeric of the HLA-C gene. In this respect, the corneodesmosin (CDSN) gene 160-kb telomeric of HLA-C is a strong candidate because of its location and its functional role in corneocyte cohesion and desquamation. In fact, a significant association between CDSN polymorphism and psoriasis was recently recognized in Caucasian populations. However, this association has not been replicated in other studies, being still controversial. In this study, we investigated the genetic polymorphism of the CDSN gene in 139 psoriasis patients and 144 healthy controls in the North-eastern Thai population. By direct sequencing technique, a total of 28 polymorphic sites were found, consisting of 26 single nucleotide polymorphisms (SNPs) and two indels (insertion/deletion). Among them, six SNPs have not been previously reported. Through this analysis, as many as 28 different SNP/indel haplotypes within the CDSN gene were identified. Seven SNPs and one indel, namely 9C, 614 A, 722T, 971T, 1215G, 1243C, 1331G and 1606AAG (deletion), revealed significant deviation in the allelic frequencies of the patients from those of the healthy controls. However, none of them are likely to be responsible for controlling the susceptibility of psoriasis, but these associations can be explained by a linkage disequilibrium to a real pathogenic allele of a nearby gene. Further, the large variations between the CDSN SNP/indel haplotypes and the psoriatic major histocompatibility complex (MHC) haplotypes also make it unlikely that CDSN is a major psoriasis-susceptible gene.

A new ISOL-based radioactive nuclear beam (RNB) facility has been constructed as a joint project of the High Energy Accelerator Research Organization (KEK) and the Japan Atomic Energy Research Institute (JAERI) at the Tandem accelerator of the Tokai site of JAERI. It uses heavy-ion linacs and related equipment of the presently closed KEK-RNB facility. Fission fragments with energy from 0.1 to 8 MeV/u will be available at this facility.

Sophistication of the transmission format for 40-Gb/s/ch WDM networks is indispensable. In long-haul transmission applications, the selection of transmission format should be a principal issue. Recently, we have proposed several transmission formats including carrier-suppressed return-to-zero (CS-RZ) and duo-binary-carrier-suppressed (DCS-RZ), in so doing addressing the issue of superior performance versus fiber nonlinearity and spectral efficiency. The special spectrum structure of these formats enables a novel mode-splitting detection scheme. The scheme realizes a variety of applications in 40-Gb/s/ch transmission; including expansion of dispersion tolerance, automatic dispersion compensation, and BER improvement. We achieved 1.6 times. expansion of dispersion tolerance of 43-Gb/s DCS-RZ signals by introducing mode-splitting in the receiver. By applying the mode-splitting scheme for CS-RZ signals, we also demonstrated precise chromatic dispersion measurement with its sign detection without the need for any dithering operation and its application to automatic dispersion compensation at 43-Gb/s CS-RZ transmission.

In order to examine the relationship between corneodesmosin (CDSN) and psoriasis we have determined the presence of CDSN polymorphisms by DNA sequencing in (a) nine B-LCL cell lines of major histocompatibility complex ancestral haplotypes known to be associated with psoriasis vulgaris including 13.1AH, 46.1AH, 46.2 and 57.1AH, and in (b) a group of 267 unrelated individuals comprising Japanese psoriasis patients (n = 101) and Japanese subjects without the disease (n = 166). Three novel CDSN gene sequences were identified. In addition, we have classified the 18 alleles into seven main groups based on phylogeny of non-synonymous substitutions. However, we have found no statistically significant differences between the patients and the unaffected individuals in any of these groups. These findings indicate that CDSN is not a major psoriasis susceptibility gene.

Novel polymorphic microsatellite markers in the human MHC class II region and methods for disease mapping and genotyping with said microsatellite markers are provided. Said microsatellite markers are useful in HLA-related research, such as genetic mapping of HLA class II associated diseases, transplantation matching, population genetics, and identification of recombination hot spots as well as linkage disequilibrium studies.

The intensely studied MHC has become the paradigm for understanding the architectural evolution of vertebrate multigene families. The 4-Mb human MHC (also known as the HLA complex) encodes genes critically involved in the immune response, graft rejection, and disease susceptibility. Here we report the continuous 1,796,938-bp genomic sequence of the HLA class I region, linking genes betweenMICBandHLA-F. A total of 127 genes or potentially coding sequences were recognized within the analyzed sequence, establishing a high gene density of one per every 14.1 kb. The identification of 758 microsatellite provides tools for high-resolution mapping of HLA class I-associated disease genes. Most importantly, we establish that the repeated duplication and subsequent diversification of a minimal building block,MIC-HCGIX-3.8–1-P5-HCGIV-HLA class I-HCGII, engendered the present-day MHC. That the currently nonessentialHLA-FandMICEgenes have acted as progenitors to today’s immune-competentHLA-ABCandMICA/Bgenes provides experimental evidence for evolution by “birth and death,” which has general relevance to our understanding of the evolutionary forces driving vertebrate multigene families.

The HLA-Cw6 antigen has been associated with psoriasis vulgaris despite racial and ethnic differences. However, it remains unclear whether it is the HLA-Cw6 antigen itself or a closely linked, hitherto unidentified, locus that predisposes to the disease. Here, in order to map the susceptibility locus for psoriasis vulgaris precisely within the HLA class I region, 11 polymorphic microsatellite markers distributed throughout a 1060 kb segment surrounding the HLA-C locus were subjected to association analysis in Japanese psoriasis vulgaris patients. Statistical analyses of the distribution and deviation from Hardy-Weinberg equilibrium of the allelic frequency at each micro-satellite locus revealed that the pathogenic gene for psoriasis vulgaris is located within a reduced interval of 111 kb spanning 89-200 kb telomeric of the HLA-C gene. In addition to three known genes, POU5F1, TCF19 and S, this 111 kb fragment contains four new, expressed genes identified in the course of our genomic sequencing of the entire HLA class I region. Therefore, these seven genes are the potential candidates for susceptibility to psoriasis vulgaris.

Mechanisms determining short-channel effects (SCE) in fully-depleted (FD) SOI MOSFETs are clarified based on experimental results of threshold voltage (V/sub T/) dependence upon gate length, and analysis using a two-dimensional (2-D) device simulator. Drain-induced barrier lowering (DIBL) effect is a well known mechanism which determines the SCE in conventional bulk MOSFETs. In FDMOSFETs, two more peculiar and important mechanisms are found out, i.e., the accumulation of majority carriers in the body region generated by impact ionization, and the DIBL effect on the barrier height for majority carriers at the edge of the source near the bottom of the body. Due to these peculiar mechanisms, V/sub T/ dependence upon gate length in the short-channel region is weakened. It is also shown that floating body effects, the scatter of V/sub T/, and transient phenomena are suppressed due to the SCE peculiar to FD MOSFETs.

An ISOL-based radioactive nuclear beam facility is just about to come into operation at INS. The present status of the INS radioactive nuclear beam project is reported. The capability of the facility and possible experiments are also discussed, including research programs of nuclear physics and nuclear astrophysics.

This paper proposes a method for measuring the local zero-dispersion wavelength at the input-side of dispersion-managed optical fibers. The method utilizes the interaction between nonlinear effects and the phase-modulation to amplitude-modulation (PM-AM) conversion due to group velocity dispersion (GVD). The interaction shifts the wavelength yielding the minimum amplitude-modulation, which is described analytically by using the adiabatic model of modulation instability (MI). An experiment in the laboratory agrees well with the theoretical values, and confirms the feasibility of this method. The local zero-dispersion wavelength of the effective lengths of actually installed cables is successfully measured by the proposed method.

This paper proposes forward error correcting (FEC) code for synchronous digital hierarchy (SDH) fiber optical transmission systems. They are (18880, 18865) and (2370, 2358) shortened Hamming codes and are encoded at the multiplex-section layer; the check bits are embedded in auxiliary multiplex-section overhead (MSOH) bytes. The codes realize general circuit configurations regardless of the transmission speed or path-size, perfect compatibility with SDH format, suppressed processing delay accumulation, and decrease the chance of line-switching in the case of signal degradation. To ensure that the various requirements of each network-provider such as customized usage of SOH bytes and affordable circuit scale could be satisfied, a trial circuit board was constructed on the programmable hardware called PROTEUS, which enables flexible operation in terms of code-selection and check bit area. We actually confirm error-correcting capability through the first STM-64 FEC-coded-optical transmission experiment. The statistics of error occurrence in the optical transmission line are also studied. The result indicates that the proposed codes are effective in optical transmission systems if the BER is limited by optical noise and dispersion.

At the cooler-synchrotron TARN II, light- and heavy-ion beams are stored, electron-cooled and accelerated for the research of atomic physics and accelerator studies. In these experiments, the closed orbit distortion (COD) correction system plays an important role for improving the beam currents and lifetimes. In order to measure the position of a circulating faint beam in the ring, we developed beam diagnostic devices of high sensitivity and low noise. The beam positions can be measured with an accuracy of 0.3 mm at a circulating beam current of 1 μA. It is the purpose of the present paper to describe details concerning the beam position monitor (BPM) system, an investigation of the sensitivities of the BPM from the point of view the S N ratio, the experimental results of a COD correction and measurements of the accelerator parameters, such as the chromaticity and dispersion using this system.

A beam extraction method using a transverse rf electric field with amplitude and frequency modulation has been studied in order to develop an irradiation method which is synchronized with the breathing of a patient for high-quality charged particle therapy. The dependence of the extracted beam intensity on the voltage, the frequency band width and the center frequency of the transverse rf electric field has been investigated. The extracted beam intensity was slightly increased from that of the ordinary slow extraction method with a third order resonance. The response of the extracted beam intensity to the applied transverse rf electric field was as prompt as within 1 ms. The horizontal emittance of beams extracted by the present method was reduced by about 70% compared with that by the ordinary one due to utilizing a constant separatrix. Amplitude modulation can control the global beam spill structure. The frequency modulation reduced the effect of the current ripple of the main quadrupole magnets.

Buried wires with lateral potential barriers provided by AlGaAs/GaAs heterointerfaces have been fabricated by wet etching and metalorganic chemical vapor deposition regrowth. Burying the wire was proven to enhance the electrical transport properties; for example, it decreased the critical width and increased the subband energy separation. Two‐dimensional simulation using the Poisson equation was performed to obtain the potential profile of both as‐etched and buried wires. The quantum energy levels corresponding to the lateral confinement were calculated for the obtained potential profiles. The calculated energy separations agreed well with the experimental ones and the subband energy separation of the buried wire was larger than that of the as‐etched wire for the same effective width. These results show that burying wire is effective for creating strong lateral confinement.

We investigated the effect of addition of sugars to a vitrification solution on the survival rate of bovine blastocysts produced in vitro. In vitro-matured (IVM) and in vitro-fertilized (IVF) bovine Day-6 to Day-8 bovine blastocysts were classified into 3 developmental stages: early blastocysts, blastocysts and expanded blastocysts. The blastocysts were cryopreserved in 1 of 3 vitrification solutions: 1) 25% glycerol25% ethylene glycol (GE); 2) 20% glycerol20% ethylene glycol3/4 M sucrose (GES); and 3) 20% glycerol20% ethylene glycol3/8 M sucrose3/8 M dextrose (GESD). The basic solution was Dulbecco's PBS supplemented with 20% of fetal calf serum. Embryos were exposed to each vitrification solution in 3 steps, and after loading into 0.25-ml straws, were plunged into liquid nitrogen. After warming in water bath at 20 degrees C, cryoprotectants were diluted in 1/2 M and 1/4 M sucrose each for 5 min. Equilibration and dilution procedure except warming were conducted at room temperature (23 to 27 degrees C). After dilution, the embryos were cultured in Ham's F10 medium0.1 mM beta-mercaptoethanol20% fetal calf serum. Survival rates of embryos at 48 h of incubation of each of the 3 developmental stages (early blastocysts, blastocysts and expanded blastocysts) exposed to the 3 types of the vitrification solutions (GE, GES and GESD) were 23.5, 33.3, 65.8% (early blastocysts, blastocysts and expanded blastocysts respectively) in GE, 55.6, 71.9, 90.5% in GES and 84.6, 83.3, 95.8% in GESD respectively. These results indicate that a mixture of 25% glycerol25% ethylene glycol is not suitable for vitrification of early bovine blastocysts; however, addition of sugars to the solution significantly (P

The heavy ion cooler synchrotron, TARN-II, has been operated for studies of accelerator technology and atomic physics since 1989 at the Institute for Nuclear Study, University of Tokyo. The ring has a circumference of 78 m and the vacuum pipe is made of SUS 316L stainless steel. The vacuum system consists of ion pumps, titanium sublimation pumps and turbo-molecular pumps. Beam experiments like acceleration, electron cooling, and extraction have been carried out at a mean pressure of the order of 10 −10 torr. In 1991, the upgrading of TARN-II vacuum system had been performed by adding ion pumps and titanium sublimation pumps in order to promote the experiments using heavy ion beams. Ion beams such as p, D, H 2 + , H 3 + , 3 He + , 4 He 2+ , HD 2 + , 4 HeH + , 14 N 5+ and 14 N 7+ have been injected and circulated in the ring so far.

A slow beam extraction system using the third order resonance has been constructed at TARN II and beam extraction tests have been performed. By the ordinary scheme where the tune is shifted to the resonance with ramping the excitation strength of the lattice quadrupole magnets, an extraction efficiency of 90% is attained. A new scheme increasing the horizontal emittance of the circulating beam is applied to extract the beam. A very long beam spill of 800 s is obtained by this scheme. A method using a transverse rf field is also studied experimentally, resulting in an extracted beam with smaller emittance.

AlGaAs/GaAs ballistic collection transistors (BCTs) are investigated by self-consistent Monte Carlo simulation, focusing on the space-charge effect in the collector region. In addition to the conventional BCT collector structure (i-p/sup +/-n/sup +/), modified collector structures which have n/sup -/-p/sup +/-n/sup +/ and p/sup -/-p/sup +/-n/sup +/ doping profiles are examined. By taking account of the fact that the collector delay time is composed of transit time and capacitance charging time, it is shown that the n/sup -/-p/sup +/-n/sup +/ collector structure is effective for the suppression of the base-widening effect (Kirk effect) compared to the i-p/sup +/-n/sup +/ or p/sup -/-p/sup +/-n/sup + /structure. Donors in the n/sup -/ layer compensate for the negative space charges produced by near-ballistic electrons. For a simulated BCT with an n/sup -/-p/sup +/-n/sup +/ collector, the smaller collector capacitance charging time leads to improvement in current-gain cutoff frequency under high current injection. >

Minority-electron transport properties in p-GaAs have been investigated using time-of-flight (TOF) and time-integrated/time-resolved photoluminescence (PL) measurements. It was found that with an increase in hole concentration the drift velocity decreases, a thermal nonequilibrium energy state exists between electrons and holes, and the energy relaxation time decreases. By combining these experimental data with a Monte Carlo calculation the scattering mechanisms in highly doped semiconductors were clarified. It was also found that energy and momentum transfers during the electron-hole interaction play an important role in the minority-electron transport for p-GaAs. This investigation revealed that the combination of an experimental approach using optical techniques, such at TOF or PL, with a theoretical approach such as a Monte Carlo calculation is indispensable in clarifying hot-carrier transport.

This experiment was conducted to determine if bovine embryos derived from in vitro maturation, fertilization and culture could develop in serum-free medium. Oocytes were matured and cultured in TCM199 supplemented with or without fetal calf serum (FCS), and in TCM199 supplemented with growth factors (GF-TCM199), namely epidermal growth factor, insulin and transferrin. The proliferation of cumulus cells co-cultured with embryos was also examined. The highest rate of embryo cleavage (48%; 2-cell/total) and blastocyst formation (30%; blastocyst/2-cell) was obtained in serum-supplemented medium, and the extensive cumulus cells proliferation formed a monolayer within 3 d of culture. In TCM199 alone, no cleaved embryos developed to the blastocyst stage, and very limited cell proliferation was observed. In GF-TCM199, 3% of cleaved embryos developed to the blastocyst stage. The collagen-coated dish improved cumulus cell growth, and the rate of blastocyst formation was 8%. The viability of these embryos was judged by transfer, with one of the three recipients becoming pregnant and delivering one calf. In conclusion, the results indicated that collagen-coating and growth factors-supplementation can support embryonic development in serum-free TCM199; however, development in vitro was significantly less extensiver than that in serum-supplemented TCM199.

Fully ion-implanted n/sup +/ self-aligned GaAs MESFETs with Au/WSiN refractory metal gates have been fabricated by adopting neutral buried p-layers formed by 50-keV Be-implantation. S-parameter measurements and equivalent circuit fittings are discussed. When the Be dose is increased from 2*10/sup 12/ cm/sup -2/ to 4*10/sup 12/ cm/sup -2/, the maximum value of the cutoff frequency with a 0.2- mu m gate falls off from 108 to 78 GHz. This is because a neutral buried player makes the intrinsic gate-source capacitance increase markedly, while its influence on gate-drain capacitance and gate-source fringing capacitance is negligible. The maximum oscillation frequency recovers, however, due primarily to the drain conductance suppression by the higher-concentration buried p-layer. An equivalent value of over 130 GHz has been obtained for both 0.2- mu m-gate GaAs MESFETs. >

Optical virtual concatenation (OVC) is a promising technique for data-intensive, latency-sensitive and large-scale applications. In this paper, we present an OVC-based network architecture and key technologies for achieving virtual bulk-data transmission with a group of wavelengths. To offset the relative delay-difference among the grouped optical channels (wavelengths), a dynamic detection and compensation mechanism based on 40-Gb/s/ch OTN physical-layer multiframe architecture is proposed and discussed in detail. Using recently developed OVC hardware, 40-Gb/s/ch parallel transmission is demonstrated for the first time, and system performance is evaluated.

Angular distributions of the differential cross section σ (θ), analyzing power Ay (θ), spin-flip probability S(θ) and spin-flip asymmetry e (θ) in the excitation of the first 2+ states in 48Ti and 50Ti were measured at incident energies of 11 and 18 MeV using (p, p' γ) coincidence technique with polarized proton beam. The results were analyzed in terms of a macroscopic coupled channels method based on the vibrational model and of the microscopic distorted wave Born approximation (DWBA) based on shell-model wave functions and effective nucleon-nucleon interactions.

Angular distributions of the differential cross section, analyzing power, spin-flip probability, and spin-flip asymmetry in the excitation of the first 2{sup +} states in {sup 48}Ti and {sup 50}Ti were measured at incident energies of 11 and 18 MeV using the ({ital p},{ital p}{prime}{gamma}) coincidence technique with a polarized proton beam. The angular distributions show strong incident energy and target dependence. The results were analyzed in terms of a macroscopic coupled-channels method based on the vibrational model and of the microscopic distorted wave Born approximation based on shell-model wave functions and effective nucleon-nucleon interactions. The spin-flip asymmetry is quite sensitive to the spin-dependent part in the interaction that causes inelastic scattering.

OTN functions-integrated LSI offers several functions to support 40G-DWDM systems: 2 kinds of 40G FECs, OTN/SDH/10GE-LAN processing, and coding for advanced modulation formats. 4 times 10GE-LAN transparently multiplexed DQPSK transmission is successfully conducted.

An ISOL‐based radioactive nuclear beam facility, Tokai Radioactive Ion Accelerator Complex (TRIAC), has been jointly constructed by High Energy Accelerator Research Organization (KEK) and Japan Atomic Energy Agency (JAEA). The facility started to provide RNBs for experiments in 2005. RNBs, including fission fragments with energies up to 1.1 MeV/nucleon, are available. The experiments were performed with accelerated 8Li beams of various energies. Current status of the equipments and preliminary results on these experimental studies are presented.

We describe the navigation system of our experimental vehicle. In this system the path planning strategy is organized hierarchically. Each level has its own map and carries out planning based on the situation the vehicle confronted using its map and sensory data. Furthermore, to improve real time operation, various modules (path planing, position estimation, obstacle detection and avoidance, etc.) of the navigation system are executed independently. Incorporation several kinds of planning strategies and maps enables the vehicle to perform suitable planning and movement for various environments in real time.

A scientific parallel processor called the R256 has been developed. The R256 is composed of 16x16 processing elements, and has the outstanding features of a “distributed parallel network” as well as on IEEE 80-bit extended floating point computation ability. The computation accuracy, required by an exhaustive number of iterations in scientific computations, is resolved by the dedicated 80-bit VLSI processor, which was developed here for the R256. The innovative distributed parallel network was designed so as to effectively resolve heavy communication problems, which are found in applications based on the Monte Carlo simulation technique. The R256 network was very economical at a hardware cost of √ N -folds (16 folds in this case) to that of an ideal full-crossbar switch, at the same time keeping the rates comparable to that of an ideal switch. The R256 demonstrates high performance of 2-GB/s data transfer rates and 500-MFLOPS computation rates on a semiconductor device simulation application.

We examined the expression of the midkine (MK) and alpha-fetoprotein (AFP) genes in 15 paired human specimens obtained from hepatocellular carcinoma (HCC) and the corresponding noncancerous regions of the same patients. A total of 14 HCC but none of the noncancerous specimens were positive for the MK mRNA. In contrast, three HCC specimens and one corresponding noncancerous sample out of the three AFP-positive HCC cases expressed the AFP gene. A 2.3-kb genomic fragment in the regulatory region of the MK gene could activate a fused reporter gene in both AFP-producing and -nonproducing HCC lines, and the MK fragment-mediated transcriptional activity was comparable to the AFP enhancer-linked AFP promoter in AFP-producing cell lines. The AFP-producing but not AFP-nonproducing HCC cell lines that were transfected with the MK promoter-linked herpes simplex virus-thymidine kinase (HSV-TK) gene became susceptible to a prodrug ganciclovir to a similar degree of the HCC transfected with the enhancer-linked AFP promoter-fused HSV-TK gene. These data suggest that the MK promoter can activate a therapeutic gene preferentially in HCC and is as useful as the AFP promoter in clinical settings.

Psoriasis vulgaris, a common inflammatory skin disorder, is known to be associated with the HLA-Cw*06 allele. It has been recently suggested by microsatellite mapping that a real susceptible gene for psoriasis resides in the approximately 100-kb genomic region telomeric of the HLA-C gene. In this respect, the corneodesmosin (CDSN) gene 160-kb telomeric of HLA-C is a strong candidate because of its location and its functional role in corneocyte cohesion and desquamation. In fact, a significant association between CDSN polymorphism and psoriasis was recently recognized in Caucasian populations. However, this association has not been replicated in other studies, being still controversial. In this study, we investigated the genetic polymorphism of the CDSN gene in 139 psoriasis patients and 144 healthy controls in the North-eastern Thai population. By direct sequencing technique, a total of 28 polymorphic sites were found, consisting of 26 single nucleotide polymorphisms (SNPs) and two indels (insertion/deletion). Among them, six SNPs have not been previously reported. Through this analysis, as many as 28 different SNP/indel haplotypes within the CDSN gene were identified. Seven SNPs and one indel, namely 9C, 614 A, 722T, 971T, 1215G, 1243C, 1331G and 1606AAG (deletion), revealed significant deviation in the allelic frequencies of the patients from those of the healthy controls. However, none of them are likely to be responsible for controlling the susceptibility of psoriasis, but these associations can be explained by a linkage disequilibrium to a real pathogenic allele of a nearby gene. Further, the large variations between the CDSN SNP/indel haplotypes and the psoriatic major histocompatibility complex (MHC) haplotypes also make it unlikely that CDSN is a major psoriasis-susceptible gene.

This paper describes the jitter requirement for high-speed optical transmission systems. It shows that the phase margin and the static phase offset are important parameters in determining the jitter requirement. Jitter requirements for high-speed (>40Gbps) optical transmission systems are discussed, including system design considerations, optical nonlinear effects and FEC related issues.

The major histocompatibility complex (MHC) is known to have a role in the development of non-melanoma skin cancer (NMSC), although the genes and mechanisms involved have yet to be determined. To identify the susceptibility locus for NMSC within the MHC, we used a collection of well-defined polymorphic microsatellite markers from the Human leucocyte antigen (HLA) region for an association analysis of 150 cases with NMSC and 200 healthy controls selected from the Busselton population in Western Australia. High-resolution mapping was undertaken using a total of 40 highly polymorphic markers located at regular intervals across the HLA region (3.6Mb). Polymerase chain reaction (PCR) analysis was initially performed on pooled DNA markers to detect those markers that showed different allele profiles. Statistically significant differences in allelic frequencies (differentiating alleles) were found between cases and controls at three polymorphic microsatellite loci within a 470-kb genomic susceptibility region ranging between 6 kb centromeric of the HLA-B gene and intron 5 of the DDR gene. Interestingly, this genome region corresponded completely with the psoriasis-susceptibility locus. The three differentiating alleles and another four markers outside the susceptibility region were then PCR tested by individual genotyping of cases and controls. The newly identified susceptibility locus for NMSC within the MHC was found to be significantly different between the cases and controls by comparisons of allele frequencies at the three differentiating loci estimated from DNA pools and then confirmed by individual genotyping. This is the first study using high density microsatellite markers to localize a NMSC susceptibility region within the human genome.

A two-dimensional device simulator for laser diodes is introduced, and its capability for quantitative device design of InGaAsP lasers is shown. This static and dynamic device simulator is based on the self-consistent analysis of five basic equations (Poisson's equation, current continuity equations for electrons and holes, the wave equation, and the rate equation for photons). The simulator has been applied to the optimum design of simplified buried-heterostructure (BH) lasers. The simulator has made it possible to optimize device structure with respect to several requirements, such as low threshold current, low leakage current, fundamental transverse lasing mode, and high-frequency modulation capability. >

Two-dimensionally-quantized electron transport in modulation-doped double-heterojunction structures is investigated using a Monte Carlo simulation. Enhanced low-field mobility in the quantum well is observed. This results from the reduction of optical phonon scattering rates, which can be attributed to the spread of the two-dimensional electron gas. It is demonstrated that the carrier transport related to this enhancement and carrier confinement effectively contribute to device operation in a double-heterojunction FET. >