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We have measured the thermal conductivity in the $ab$ plane of ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ $(x=0.10,0.115,0.13)$ in magnetic fields up to $14\phantom{\rule{0.3em}{0ex}}\mathrm{T}$ parallel to the $c$ axis and also parallel to the $ab$ plane. By the application of magnetic fields parallel to the $c$ axis, the thermal conductivity has been found to be suppressed at low temperatures below the temperature ${T}_{\ensuremath{\kappa}}$ which is located above the superconducting transition temperature and is almost independent of the magnitude of the magnetic field. The suppression is marked in $x=0.10$ and 0.13, while it is small in $x=0.115$. Furthermore, no suppression is observed in the $1%$ $\mathrm{Zn}$-substituted ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{Cu}}_{0.99}{\mathrm{Zn}}_{0.01}{\mathrm{O}}_{4}$ with $x=0.115$. Taking into account the experimental results that the temperature dependence of the relative reduction of the thermal conductivity is quite similar to the temperature dependence of the intensity of the incommensurate magnetic Bragg peak corresponding to the static stripe order and that the $\mathrm{Zn}$ substitution tends to stabilize the static order, it is concluded that the suppression of the thermal conductivity in magnetic fields is attributed to the development of the static stripe order. The present results suggest that the field-induced magnetic order in ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ originates from the pinning of the dynamical stripes of spins and holes by vortex cores.

The PF‐AR is a full‐time single‐bunch light source for SR experiments in the X‐ray region. Electrons are injected at 3.0 GeV and ramped up to the final energy of 6.5 GeV for normal user operation or 5.0 GeV for medical application. The typical initial beam current is 55 mA at 6.5 GeV and the beam lifetime is 15 h at 50 mA. The initial single‐bunch impurity better than 10−8 was achieved, however, degradation of the impurity during the users’ run has to be solved. Since the present emittance of 290nm⋅rad is not satisfactory, we are making an effort to realize the minimum attainable emittance of 160nm⋅rad. The high quality of pulse X‐ray has brought us abundant occasions to do time‐domain and/or time‐resolved measurements.

Photodisintegration cross sections were measured for deuterium with Laser Compton scattering γ beams at Eγ = 2.3 – 4.6 MeV. The experimental evaluation of R(E) = Naσv for the p(n,γ)D reaction was performed in the energy region relevant to big bang nucleosynthesis (BBN) by using the present data combined with the preceding data. The result confirms the past theoretical evdaluation with 6% uncertainty. The reaction rate for the p(n,γ)D reaction is presented for the BBN in the precision era.

The authors have developed a new kind of tunable distributed Bragg reflector (DBR) laser that has a tunable stair guide. This allows continuous wavelength tuning when using single current injection. The laser was fabricated by two-step selective area metal organic vapour phase epitaxy. A continuous wavelength tuning range of 3.8 nm at a wavelength of 1.55 µm was achieved.

Selective MOVPE has many unique characteristics such as in-plane layer-thickness control and bandgap-energy control, which are achieved simply by changing the mask pattern. Narrow-stripe selective MOVPE (NS-MOVPE) offers further advantages because of its direct waveguide formation capability because no semiconductor mesa etching is needed to form DFB laser diode active layers and optical waveguides. Consequently, this technique has been extensively used to build various kinds of photonic devices and has achieved highly uniform device characteristics. NS-MOVPE can be used potentially to fabricate various advanced photonic devices for future WDM networks.

Disruption of the thoracic aorta due to blunt chest trauma is often fatal and should generally be treated surgically as soon as possible. However, cases of disruption of the thoracic aorta due to blunt chest trauma are often complicated by damage to vital organs, making treatment difficult. Our policy is to treat other organs before treating the thoracic aorta in 1) cases in which fracture of the pelvic bone or bleeding from abdominal cavity organs is causing shock and 2) cases of severe cerebral contusion or intracranial hemorrhage that require emergency surgical treatment. The use of a stent for treatment of acute-stage cases should be considered prudently.

In this work, the thermal neutron field at the Heavy Water Neutron Irradiation Facility of the Kyoto University Reactor, which had been used for boron neutron capture therapies for several years, was characterized. The spatial distributions of the thermal neutrons were measured with a small thermal neutron probe that was put on a tip of an optical fiber with a diameter of 1 mm. The probe consisted of ZnS(Ag) and LiF as a neutron converter. The probe was very small so that the detector could measure the spatial distribution with an excellent spatial resolution and without disturbing the thermal neutron field. The results were compared with that obtained with a conventional gold wire activation method and Monte Carlo calculations.

We developed EA-modulator integrated DFB-LDs covering 1.56-/spl mu/m to 1.61-/spl mu/m wavelengths on a single wafer, and tested them in long-distance transmission experiments for the first time to our knowledge. Transmissions at 2.5 Gbit/s over 600 km and 10 Gbit/s over 500-ps/nm dispersion were successfully demonstrated.

The partial discharge and breakdown characteristics of polymer-film/silicone-oil composite dielectrics were studied using a needle-plane electrode system. In most of the experiments, DC voltage was applied at 0.5 kV/s until breakdown. Some tests were performed at rates of voltage increase of 1.5 and 3.0 kV/s. It is shown that with the needle positive, breakdown initiates in the oil from the needle tip and the polymer barrier increases the system's breakdown voltage. With the needle negative, the breakdown of the composite system occurs just after the partial discharge is initiated, indicating that partial-discharge inception is closely related to the breakdown of the composite system. The breakdown voltage is dependent on the negative accumulated charges on the film. These create a high stress across the film and cause breakdown of the composite system. >

A long-pulse modulator for the 1-GeV proton linac planned at KEK (Japan National Laboratory for High Energy Physics) was designed and constructed as a prototype and a component for testing developed klystrons and other power devices. The modulator is a standard line-type. The output pulse has a 15-MW peak power, 200- mu s pulse width, and 150-kW average power (600 mu s and 450 kW are the final phase objectives). Design parameters and operating characteristics are discussed. >

In the summer of 1988, sixteen superconducting RF cavities were installed to increase the beam energy of TRISTAN and they began effective operation in November. Special equipment was introduced to solve problems connected with oxygen deficiency and air pollution by synchrotron radiation. An air pollution monitoring system that detects oxygen deficiency and contaminated air in the tunnel was introduced into the previous distributed safety and interlock system (DSIS). The system includes detectors for oxygen deficiency, for ozone and nitrogen dioxide, and for a small amount of smoke. It monitors the environmental pollution in the tunnel and acquires the information necessary for safe operation of TRISTAN. DSIS and the new system are functionally separate, but the latter is hierarchically connected to the former to provide interlock signals for other accelerator devices. >

The effects of polarizing field, polarizing temperature, filler concentration, and surface treatment of filler on the TSC (thermally stimulated current) of filled EPR (ethylene-propylene rubber) are described. The TSC results show that the samples with different fillers yield considerably different TSCs in spite of containing the same EPR polymer. The results suggest that the main peak of the measured TSC of the homemade samples is due to the trapped charge carriers in the regions between the EPR polymer and filler. The fact that the silica-filled sample showed a considerably larger TSC than the zeolite-filled sample can be explained by the difference in the structure of the inorganic filler. The abrupt decrease of the TSC of the silica-filled sample above 17 wt% silica is attributed to the clustering and association of filler. >

In this study, an acoustic thermometry in a glasshouse using a sound probe is described. The real time measurement of air temperature is important for the appropriate control of ventilation windows of the uniform cultivation environment in the large scale greenhouse. The sound probe, which consisted of a pair of a loud speaker and a microphone, was used for the temperature measurement. The propagation velocity of the sound is dependent on the air temperature. The velocity is acquired from the time of flight (TOF) of the sound. Mean temperature along the sound probe is measured by the TOF of the sound. This technique was tested using a quarter part of a twin-span glasshouse (60.6 m x 14.8 m) with no crops. The mean temperature along with the distance of 21.0 m was measured by the sound probe for 30 hours. The result showed that the technique was appropriate compared with the simultaneous measurement of eight thermocouples. The result also showed that the effect by solar radiation was negligible. The proposed technique realized the temperature measurement of the large greenhouse.

A high duty UHF (432-MHz) RF source for the intense proton linac of the Japanese Hadron Project (JHP) has been constructed at KEK. A test-linac consisting of a RFQ and a drift-tube (DTL) structures is under construction. The UHF RF power generated by 2-MW peak power klystron will be fed into these structures with 650 /spl mu/sec pulse-duration and 50 Hz repetition-rate through an waveguide system with a Y-junction circulator. A dc high voltage (max. 95 kV) is applied to a cathode of the klystron and a beam current is modulated up to 40 A by a pulsed high voltage (max. 80 kV) applied to a modulating anode. The klystron power supply can operate two such klystrons simultaneously with two individual anode modulators. The first operation of this RF power source and the preliminary test of an RF signal processing such as PLL and ALC are reported. >

Using the narrow-stripe selective MOVPE technique, high quality InGaAsP-InGaAsP MQW was obtained. Fine selectivity and large bandgap energy shift were also obtained for InGaAs-InAlAs MQW. These results confirm extensive capability of this technique to various photonic integrated circuits (PICs) for advanced optical transmission systems.

In this study, we investigated methods of reconstructing higher-resolution three-dimensional (3D) patterns of real electrical tree patterns. We studied two kinds of reconstruction methods, and both methods were applied to the same specimen. One method is a mechanical preparation of serial cross sections and the other is a computerized tomography method using projections. Furthermore, to examine the fractal properties of reconstructed 3D tree patterns, the fractal dimension of their patterns was estimated by means of a box counting method. The results showed that both methods can reconstruct 3D electrical tree pattern accurately and the obtained patterns have fractal properties. >

The variations of pulse height and energy resolution at a full energy peak depending on the direction of charged particles produced by thermal neutrons in cylindrical /sup 3/He proportional counters have been measured using a pulse shape analysis. The difference of peak positions affected by charged particles having mainly "parallel direction" and "any other direction" to the anode wire was found to be 1%, and this difference became larger with increasing bias voltage. The difference of energy resolution was about 1% under normal bias operation. The optimum bias voltage to get the better energy resolution was different in each group. It is concluded that, as a result of space charge effects, the direction of charged particles to the anode wire affects the variations of pulse height, energy resolution and the optimum bias voltage in the proportional counter. The experimental results also suggest the improvement of the energy resolution by selecting the "parallel direction" component of charged particles to the anode wire. >

The authors describe the fractal properties of the branches of actual electrical trees under AC or impulse voltage. In addition to the observation of the actual electrical trees, the preparation of the simulated trees by using a personal computer is performed in a 2-dimensional space and a 3-dimensional space in order to simulate the actual electrical trees. To examine the fractal properties of both actual electrical trees and simulated trees, the fractal dimension is calculated by using the scale covering method. The electrical tree patterns obtained have fractal properties and their patterns can be classified and quantified by means of fractal dimension. Furthermore, the 2-dimensional and 3-dimensional simulated trees produced by a personal computer are similar to the actual electrical trees and also have fractal properties. >

Multiple-stripe planar buried heterostructure (MS-PBH) was newly developed to improve the high-temperature characteristics of spot-size converter integrated all-selective MOVPE-grown planar buried heterostructure laser diodes (SSC-ASM-PBH LDs). Recombination-layer stripes were simultaneously grown with the active layer and thickness-tapered waveguide by narrow-stripe selective MOVPE, and inserted in the current-blocking layers. The recombination-layer stripes effectively suppressed the leakage current in a high-temperature and high-power range. A maximum output power of 37 mW and a small dope-efficiency degradation of 1.25 dB were obtained even at 85/spl deg/C while maintaining a small coupling loss to a flat-ended single-mode fiber of less than 2.5 dB. These excellent high-temperature characteristics and good coupling characteristics are very attractive for achieving low-cost light-source modules for use in optical access networks.

We report that the characteristics of luminous intensity and current pulse of partial discharges during tree propagation in PMMA specimens can be analyzed simultaneously using the idea of chaos.

This paper examines a synchronous rectification of a forward converter that uses a constant-current circuit for the transformer reset. To reduce loss in the constant-current circuit, the converter is connected to supply some of the power to the load. The question of optimizing the reset power is considered and the power distribution is shown. The reset power was set to its optimum value, and experimental values were used to examine this. We also investigated operations under no-load and show that the converter operates normally and that the reset is being performed.

We have proposed and demonstrated novel planar-buried-heterostructure InGaAsP semiconductor MQW lasers that include oxidized AlAs current-blocking layers. These layers provide strong current confinement, thus enabling excellent lasing performance such as a threshold current of 6 mA, a slope efficiency of 0.51 W/A under CW condition and a maximum output power of up to 150 mW under pulsed condition, achieved at 25°C.

Thirty-two 20-Gb/s channels spaced by 100-GHz were transmitted over 400-km of DSF with 80-km repeater spacing. Nonlinear effects in low local dispersion were successfully suppressed by using the 1.58-/spl mu/m band and optimizing the dispersion map and the initial chirp.

A peak pile-up correction of the output pulses measured by a Ge detector is necessary for a quantitative measurement of a pulsed beam of high energy photons which are produced by Compton backscattering of pulsed laser light with relativistic electrons in a synchrotron storage ring. The peak pile-up causes not only a distortion of pulse height distribution measured by a Ge detector but also affects quantitative measurements based on integrating the area under the pulse height spectrum. In order to correct the peak pile-up, a Monte Carlo simulation has been applied to calculate the pile-up spectrum by superposing double pulse or triple pulse coincidences with different pulse heights and different time delays. It is assumed that the output pulses are randomly generated in time within one burst of the pulsed laser light. An undistorted pulse height spectrum necessary for the simulation has been obtained from a low counting rate experiment which has a negligible pile-up. A good agreement between the simulated spectrum and the experimental spectrum using different pile-up rates has been obtained. After fitting the experimental data by use of the simulated spectrum, the measured spectrum call be resolved into single, double and triple pile-up components. This results in a quantitatively corrected peak pile-up at different counting rates.

Wavelength division multiplexed (WDM) lightwave systems are expected to use many wavelength-controlled light sources. The simultaneous fabrication of different wavelength laser diodes (LDs) on a wafer is therefore an important technology which would allow WDM light sources to be prepared at low cost. The lasing wavelengths of these LDs must be precisely controlled to coincide with pre-assigned wavelength grids for WDM systems. Each LD with different wavelength should have uniform lasing characteristics. We developed a new type of wavelength controlled distributed feedback (DFB) LD. Uniform lasing characteristics were demonstrated for 40-channel different wavelength DFB LDs fabricated on one wafer, over a 75 nm-wide wavelength range.

This compact, single chip MPEG-2 audio/video decoder performs all necessary signal processing required for digital satellite TV and cable television (CATV) receivers based on the main profile at main level (MPEG-2 MP@ML) standard. This decoder uses 135,000 gates (2-input NAND equivalents) and occupies 8.6/spl times/9.3 mm/sup 2/ in a triple-layer-metal, 0.5 /spl mu/m CMOS standard-cell process and is much smaller than any MPEG-1/MPEG-2 decoder previously reported.

This paper describes the chaotic behavior of luminous characteristics in time series during AC electrical tree propagation in EVA and PMMA specimens. The authors consider the fractal dimension of the attractor, maximum Lyapunov exponents and self correlation functions, based on light intensity measurements.

In this paper, we studied voltage-dependent characteristics of the tree shapes in cross-linked polyethylene (XLPE). We also studied the effect of voids on the tree shapes. In the case of the voidless samples, the tree length shows nonmonotonic behavior. In the case of samples with recessed voids, the tree length increases with increasing applied voltage. The tree shape is considered to consist of multiple groups of branches.

The pulse height distribution in /sup 3/He proportional counters has been investigated to accurately quantify the response function to be used in fast neutron spectroscopy. The measurements were performed as a function of the operating voltage, the counting gas mixture, and the incident neutron energy. The special emphasis of this study has been put on the nonlinearity of the pulse height of a recoil helium induced by the /sup 3/He(n,n)/sup 3/He reaction. A distinct deviation of 14% at maximum to lower energies was found in the position of the recoil edge with the energy axis calibrated by the full energy peaks of the /sup 3/He(n,p)T reaction produced with neutrons of thermal energy and 2.413 MeV. It was confirmed that the nonlinear effects, such as an initial recombination and a space-charge effect, take place more significantly in the energy loss process of a recoil helium because of its higher linear energy transfer (LET) in the filling gas compared to that of a proton and triton pair emitted from the /sup 3/He(n,p)T reaction. The deviation becomes larger with an increase of the average LET in the gas mixture. The experimental results suggested that the nonlinear effect caused by a higher LET recoil helium is inevitable for the filling gas, even if the operating voltage is changed to an acceptable range.

We have developed a wavelength-selectable light source (WSL) based on microarray DFB-LD configuration that enables high fiber-coupled power operation. The WSL was grown in only two steps without any complicated semiconductor etching. Using the WSL, fiber-coupled power of more than 20 mW and stable single-mode oscillations with an SMSR of more than 50 dB were obtained for all 23 addressable ITU-T channels on a 50-GHz grid.

We report on recent progress in the development of wavelength-selectable light sources based on DFB-LD array configurations.

We studied the mask interference effect in selective metal-organic vapor-phase epitaxy (MOVPE) of a microarray optical waveguide. We investigated the characteristics of waveguides having mask interference effects. Based on the experimental results, we developed a method of simulating the characteristics of a microarray waveguide that uses the mask interference constant, which depends on growth pressure. The simulation can account for the experimental results under different growth pressures and should be very useful for designing the microarray waveguides. In particular, we can use it to control the PL-wavelength profile of the microarray waveguide grown under atmospheric pressure, which is important for fabricating densely integrated photonic devices.

Carried out a 3-dimensional tree simulation with a barrier between a point electrode and a plane electrode, based on a DBM model considering the growth probability. It was found that the results obtained from the 3-dimensional tree simulation considering the growth probability are similar to those of actual tree growth in composite insulating materials with a barrier. It was suggested that the 3-dimensional tree simulation considering the growth probability is valid for simulating the growth in composite insulating systems with barriers.

A DFB-LD array-based wavelength selectable light source is described (WSL). The WSL is very promising for DWDM applications because of its fine wavelength tunability and stability and its simple tuning scheme. Also, the advanced simple fabrication process used to produce this device is an effective one. Further optimizations of device structure make this type of device a practical light source for DWDM transmission systems.

We developed multi-range wavelength-selectable light sources (WSLs) with an all-selective MOVPE (ASM) grown microarray planar-buried-hetero (MPBH) structure. We simultaneously fabricated five WSLs, each with a unique 8-nm tuning range, to cover forty 100-GHz-spaced channels (the entire C-band). Uniform characteristics, such as an I/sub th/ of 8.3 /spl plusmn/ 1.2 mA, an SMSR of over 45 dB, and a fiber-coupled power up to 15 mW, were obtained.

Deals with the relation between the physiological diel vertical-migration strategy of the Japanese eel (Anguilla japonica) and its transportation strategy which is related to the transfer from North Equatorial Current to the Kuroshio Current. The author investigates the diel vertical migration (DVM) of leptocephalus larvae through the transportation simulation with the genetic algorithm for understanding the various DVM strategies.

This paper proposes a new robust feedforward tracking control system for optical disk recording system, which is based on both "zero phase error tracking" (ZPET) control and a robust feedback control using disturbance observer and coprime factorization. Optical disk recording systems must have a quick and precise tracking control whose error is less than 0.1 /spl mu/m for a position reference with amplitude of 100 /spl mu/m. For this purpose, optical disk recording systems should be regulated by feedforward control and robust control. However, the detection signal is only a tracking error and the position reference cannot be obtained. Therefore, this paper proposes a new estimation method of the position reference by using only tracking error, and realizes a quick and precise tracking control based on feedforward control and robust control.

We developed compact (1.136 mm/sup 2/) eight-channel wavelength selectable microarray DFB-LDs with monolithically integrated 8/spl times/1 MMI combiner, S0A, and EA-modulator. The wavelength tuning range of 15.3 nm with uniform device characteristics and 2.5 Gbit/s modulation performance were successfully demonstrated.

Cisplatin has played a key-role in the management of ovarian cancer patients. Since the mechanisms of cisplatin-resistance have been reported to be multifactorial, it is quite difficult to predict effectiveness of cisplatin-based chemotherapy. In the present study, we have screened abnormal chromosomal regions in cisplatin-resistant and paclitaxel-resistant human ovarian cancer cell lines using comparative genomic hybridization (CGH). Increased copy number at 6q21-25 and decreased copy number at 7q21-36 and 10q12-15 were observed in the cisplatin-resistant cell line. Increased copy number at 7q11.2-21 was observed in paclitaxel-resistant cell lines. Messenger RNA of MDR1 located on chromosomal region of 7q11.2-21 was overexpressed in the paclitaxel-resistant cell lines and recognized as a potential mechanism of acquired paclitaxel-resistance. In CGH analyses of 28 primary epithelial ovarian cancer patients, gains of 1q21-22 (p = 0.0183) and 13q12-14 (p = 0.0407) were observed in significantly high abundance in the cisplatin-resistant tumor group, compared with the cisplatin-sensitive tumor group. These genetic alterations were suggested to be potential indicators for drug resistance.

The aim of this retrospective study was to elucidate the characteristics of five guidelines of community-acquired pneumonia: ATS (1993), ATS (2001), IDSA (1998), IDSA (2000) and the guidelines of the Japan Respiratory Society (2000). One hundred community-acquired pneumonia patients admitted to the International Medical Center of Japan were investigated in accordance with each set of guidelines based on the physical, laboratory, and chest radiography findings on the first day of treatment. According to the ATS (1993) guidelines, 33% of the cases were classified as "severe" pneumonia. On the other hand, according to the ATS (2001) guidelines, only 8% of the cases were classified as "severe" pneumonia. According to the IDSA guidelines, 35% of the patients were classified as "outpatients". Fluoroquinolone appears to be a very important antibiotic drug in the new guidelines of both ATS and IDSA. The scoring system of IDSA suggested a correlation between the patient's score and the pathogenic bacteria. According to the guidelines of the Japan Respiratory Society, 42% of the cases were classified as "severe" pneumonia. There are evident differences between these guidelines, and clinicians need to have a full understanding of their respective characteristics.

The modifying effects of pure curcumin on glandular stomach carcinogenesis were investigated during the post-initiation phase in male Wistar rats treated with N-methyl-N'-nitro-N-nitrosoguanisine (MNNG) and sodium chloride. A total of 110 male 6-week-old rats were divided into four groups. Groups 1-3 (consisting of 30 rats/group) were given MNNG in their drinking water at a concentration of 100 ppm and simultaneously fed a diet supplemented with 5% NaCl for 8 weeks. They were then fed a diet containing either 0.2% (group 1) or 0.05% (group 2) pure curcumin or kept on a basal diet alone (group 3) for 55 weeks. The rats of the curcumin-treated groups (groups 1 and 2) were then switched to the basal diet for the following 4 weeks before sacrifice. Group 4 (20 rats) served as a non-treatment control. The total incidence of combined atypical hyperplasias and adenocarcinomas in the glandular stomachs was rather lower in groups 1 (93%) and 2 (90%) than in group 3 (100%), albeit without statistical significance. However, the mean number of atypical hyperplasias or adenocarcinomas of the glandular stomachs in group 1 (4.70) was significantly less than the value of group 3 (7.17) (p0.05). Thus, the development of cancerous and precancerous lesions in the glandular stomach was decreased by exposure to pure curcumin. The present results indicate that the compound exerts chemopreventive effects, when given during the post-initiation phase of glandular stomach carcinogenesis in rats.

The linewidth of a 1.5- mu m wavelength single-mode phase-locked laser array was measured. A relatively narrow linewidth of 203 kHz was obtained at an output power of 25 mW for a five-element phase-locked laser array that consists of a five-pair Ga/sub 0.3/In/sub 0.7/As/GaInAsP/InP compressively strained quantum-well active region and a mode controlling grating filter. This result indicates the reduced spontaneous emission factor due to a larger cavity size in the lateral direction. >

DNA sequence from Aspergillus oryzae genome which, confers on pOK-1 the ability to replicate autonomously in Saccharomyces cerevisiae is described. A hybrid plasmid pOK-1 was constructed from pBR325 and YEp13 fragment containing Leu2+ gene. Asp. oryzae DNA and pOK-1 were cleaved with BamHI, ligated and introduced into Escherichia coli. About 600 recombinant plasmids were obtained. One of them transforms S. cerevisiae SHY3 to Leu2+ with middle efficiency. The plasmid designated as pSB1–2 contained two BamHI fragments (4.3 kb and 4.1 kb) of Asp. oryzae DNA. Klonung einer selbstandigen Replikations-Reihenfolge von Aspergillus oryzae. Die DNA-Sequenz aus dem Aspergillus oryzae-Chromosomensatz, die pOK-1 die Fahigkeit vermittelt, sich selbst in Saccharomyces cerevisiae zuruckzuverwandeln, wird beschrieben. Ein Hybriden-Plasmid pOK-1 wurde aus einem pBR325 und einem YEp13-Fragment aufgebaut, welches das Leu2+-Gen enthalt. Aspergillus oryzae-DNA und pOK-1 wurden mit BamHI gespalten und in Escherichia coli eingefuhrt. Etwa 600 rekombinante Plasmiden wurden erhalten. Eines von ihnen transformiert S. cerevisiae SHY3 in Leu2+ mit mittlerer Wirksamkeit. Das als pSB1–2 designierte Plasmid enthielt zwei BamHI-Fragmente (4.3 kb und 4.1 kb) von Aspergillus oryzae-DNA.