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An 8-GeV electron/3.5-GeV positron injector for KEKB was completed in 1998 by upgrading the existing 2.5-GeV electron/positron linac. The main goals were to upgrade its accelerating energy from 2.5 to 8 GeV and to increase the positron intensity by about 20 times. This article describes not only the composition and features of the upgraded linac, but also how these goals were achieved, by focusing on an optics design and commissioning issues concerning especially high-intensity single-bunch acceleration to produce positron beams.

KEKB has been operated since December, 1998, to deliver BB pairs for a physics detector. In this paper,we describe the commissioning procedure of KEKB.

The susceptibility and specific heat of pure single-crystal EuSe were carefully measured as functions of temperature in various magnetic fields. It is found that, below 1.5 kOe, a first-order transition occurs at Neel temperature T N and rather complicated spin structures exist in EuSe below T N , which cannot be described by the simple Heisenberg model. In the range 1.5 kOe H ⩽ 5 kOe, a second-order transition was observed at T N , and the susceptibility and specific heat exhibit the usual antiferromagnetic behaviour. Above 5 kOe, a large bump in the specific heat appears which can be understood with the ferromagnetic molecular field approximation.

過去10年間の直腸癌手術例のうち十分な郭清の行われた149例についてリンパ節転移個数別の分析を行い現行の進行度(stage)分類等と比較検討した.転移個数は予後と密接にかかわりあっていた.われわれは転移個数を転移なし群,1～2個の転移群,3～5個の群および5個を越える群の4郡に仮に区分し遠隔成績を求めたが,4群間に全て明瞭な予後の差を認めた.規約の転移範囲と対比すると少数(1～2個)の転移例の予後は転移範囲や転移方向によらず比較的良好だが,多数(3個～)の転移例は予後不良であった.転移個数は直腸癌の大きな予後定因子で,癌の悪性度を反映する簡便な指標と見なされる.その分析から従莱区別し得なかった病期分類上の予後の差が明瞭となり術後高リスク群の予測にも有用であろう.さらに郭浩範囲を適正化し縮小手術の適応決定に貢献すると思われた.今後本因子の臨床的意義を明らかにするため多施設問の情報交換が望まれる.

A series of acetylenic analogues of 3,6-bis(dimethylamino)fluorenylium dye, which absorb near-IR light (up to 1096 nm in CH2Cl2), have been systematically prepared and their characteristic lightabsorption spectroscopic properties, as well as their pKR+-values, are discussed with the aid of PPP-SCF-MO calculations, and compared with data for the corresponding unbridged triphenylmethane dye ethynologues.

A series of acetylenic analogues of 3,6-bis(dimethylamino)fluorenylium dye, which absorb near-IR light (up to 1096 nm in CH2Cl2), have been systematically prepared and their characteristic lightabsorption spectroscopic properties, as well as their pKR+-values, are discussed with the aid of PPP-SCF-MO calculations, and compared with data for the corresponding unbridged triphenylmethane dye ethynologues.

Crab cavities have been installed in the KEKB B-factory rings to compensate the crossing angle at the collision point and thus increase luminosity. The beam operation with crab crossing has been done since February 2007. This is the first experience with such cavities in colliders or storage rings. The crab cavities have been working without serious issues. While higher specific luminosity than the geometrical gain has been achieved, further study is necessary and under way to reach the prediction of simulation.

KEKB has been operating with crab cavities for the first time in the world. This paper represents beam operation with the crab crossing.

At KEKB, a dedicated machine experiment on crab crossing has been carried out for about 4.5 months. Some of the beam-beam effects observed with crab crossing, which include a beam lifetime issue, are discussed in comparison with those with a finite crossing angle of plusmn11 mrad.

Recently, we have observed vertical betatron sidebands in the transverse beam spectra of positron bunches at the KEKB LER which are associated with the presence of electron clouds.[1] When the LER is operating in single-beam mode (no colliding bunches in the HER), these sidebands are sharply peaked. When the bunches are in collision for physics running, the sidebands are still present but are found to be smeared out. The bunch-by-bunch specific luminosity is lower for bunches with sidebands than for those without sidebands. In this paper, the behavior of the sidebands in collision and the effects on luminosity are discussed.

A simulation of a build-up of an electron cloud in SuperKEKB was done by a program CLOUDLAND. Average electron density and electron density at the center of a vacuum chamber were calculated in a drift space and in various magnetic fields. The result shows that a solenoid field is very effective in reducing the electron density and the simulated electron density is below the threshold electron density of the strong head-tail instability by the electron cloud if solenoids are installed in the drift space.

We report on the recent experimental results on the fast-ion instability at the 2.5 GeV Pohang Light Source (PLS). In order to enhance the fast-ion instability in the PLS, we inserted helium gas to the storage ring in order to increase the vacuum pressure. With the gaps in the bunch train which is large enough to avoid multiturn ion trapping, we observed increase of a factor of 3-4 in the vertical beam sizes for the increased vacuum pressure up to 40 nTorr. The instability growth rate is obtained as a function of vacuum pressure and is also compared with the simulation results.

Synchro-beta side band signal caused by electron cloud instability has been observed at KEK-B factory. The side-band appears above the threshold of beam size blow-up and disappears by exciting solenoid magnets which covers whole ring. The side-band is an evidence of strong head-tail instability caused by electron cloud. The side-band appears in tune spectrum with positive shift ν β + aν s (1 β − aν s (a > 0). We study the synchro-beta spectrum using a code, PEHTS, which simulates single bunch electron cloud instability.

Movements of Beam Position Monitors due to thermal stress in high beam current operation were observed in KEKB. For high luminosity operation of KEKB, the beam current as high as 1.7 A is accumulated in the positron ring and a precise control of the beam orbit based on the BPM system is required. Though every BPM chamber is fixed firmly on a support of each quadrupole magnet, the BPM chamber moves several hundred microns from the setting position depending on the beam current due to heating of beam pipe by strong synchrotron light irradiation. Such movement introduces an unavoidable offset error in the BPM measurement, and is a serious problem not only for KEKB but also for the next generation of B-factory operated with extremely high beam current. We report the measurement of the movement by gap detectors and an attempt to correct the BPM offset error in real-time operation.

Coupled bunch instability caused by electron cloud has been observed in the KEKB-LER. Time evolution of the instabilities just after the turning-off the transverse bunch feedback have been recorded with several solenoid-field conditions to suppress the blowup due to electron cloud. The mode spectra of the coupled-bunch instabilities have been compaired with the simulations of electrons moving in drift space, weak solenoid field and strong bending field.

Transverse beam-size enlargement due to dynamic beta and emittance effects has been observed in the KEKB Low Energy Ring (LER) and High Energy Ring (HER). In order to observe these effects, a retrofocus optics system has been developed and installed in the horizontal SR interferometers at the HER and LER. This system allows us to vary the apparent beam size to match the dynamic range of the interferometer. We report on the retrofocus optics system and measurement results, and compare the measured effects with those expected from dynamic beta simulations.

Beam behaviour of KEKB was studied by measurement of the beam size using a streak camera. The effects of electron-clouds and beam-beam interactions on the vertical beam size were examined in beam collision. We injected a test bunch of positrons 2 RF buckets after a bunch to enhance the electron cloud effect and changed electron beam conditions to see the beam-beam effect. The beam size was also measured in a single positron beam condition and compared with that during collision. The result of the measurement is reported in this paper.

The upgrade project of the pulse X-ray source PF-AR was successfully completed by the end of 2001. The initial beam current and the lifetime were largely improved. The injection energy was raised from 2.5 GeV to 3.0 GeV, the maximum beam current of 65 mA was achieved. With a new global orbit feedback system, orbit drifts were largely improved.

We simulate the interaction of a bunch train with either an external wake field, (semi-)trapped ions in a field-free region or in a dipole field, or an electron cloud, on successive turns, using a simplified algorithm with only a small number of macro-particles. We present simulated mode spectra and rise times for the ensuing coupled-bunch instabilities, and show that observations at the KEKB HER are consistent with a horizontal instability driven by carbon-monoxide ions in a region without magnetic field.

We provide a multi-electrode method for measuring the bulk impedance of botanical tissues and electrode impedance used in the measurement, simultaneously. By stabbing many electrodes in the object along the circumference of the columnar body, the bulk impedance and impedance of electrodes can be measured. The impedance of the botanical body can be estimated when the number of electrodes is infinite. The experimental results applied to Japanese radish showed the usefulness of the proposed method.

This paper describes a method for measuring the grounding impedance of a tree. Electrode impedance of an electrode using for connection between the measurement circuit and the tree, brings serious error in the measurement. To avoid the effect of the electrode impedance, the four-electrode method known in the impedance measurement methodology, is newly introduced. The hybrid method of the four-electrode method and usual grounding impedance measurement method makes it possible to measure grounding impedance of the tree directly. The experiments of the measurement were conveyed for three materials, zelkova tree, cherry tree, and silk-tree with the girth of 1.7-2.0 meters. Obtained values of impedance were 60-100 O in absolute one, and they showed slight capacitive reactance. It is concluded that the presented method is available for the measurement of grounding impedance of the tree.

Electron-cloud build up, incoherent tune spread and electron-induced beam instability are likely to be responsible for the vertical beam-size increase observed at the KEKB Low Energy Ring (LER). We report on recent simulations and analytical estimates, addressing the electron-cloud evolution for various magnet configurations, comparing the beam size blow up predicted by three different simulation models (micro-bunches, multi-particle tracking with soft Gaussian approximation, particle-in-cell), and finally discussing analytical expressions for the instability threshold.

A 3-dimensional particle simulation code is developed to study the photoelectron cloud in positron rings. The effects of the various magnetic fields in the KEKB LER are presented. The distribution and evolution of the electron-cloud are simulated.

An experiment investigating the photoelectron instability has been performed in BEPC at IHEP, China. The betatron oscillation of each bunch was observed and recorded by a single pass beam position monitor system which has a capability to measure the transverse position of every bunch over 16000 turns. The effect of an octupole magnet on the instability was also studied. This paper describes results of those observations and analyses.

The first beam collision study was done in the KEKB double ring collider. Beam collision conditions were found by searching beam-beam deflection curves in a trial-and-error method. From these curves, beam sizes at IP and a luminosity was estimated.

The commissioning of the KEKB B-Factory storage rings started on Dec. 1, 1998. The two rings both achieved a stored current of over 0.5 A after operating for four months. The two beams were successfully collided several times. The commissioning stopped on Apr. 19, taking a 5-week break to install the Belle detector.

TNM classification of bone and soft tissue sarcomas was published by UICC in 1987. Histological grading (G) is an important factor in this classification, but the criteria of G categories are not so clear. In addition, lymph node metastasis is very rare in bone and soft tissue sarcoma. Therefore, prognostic factors are limited to T, M and G categories. Since correlation between the stage (UICC) and the survival rate was not found in patients with osteosarcoma, TNM classification (UICC) has not been used widely in the field of orthopedic oncology. The Musculoskeletal Tumor Committee of the Japanese Orthopaedic Association proposed another TNM classification of osteosarcoma based on multivariate analysis. T1 is less than 15 cm and T2 is 15 cm or larger in maximal diameter. N and M are same with the UICC criteria. Serum alkaline phosphatase level (A) is included in this classification in which A0 is less than the normal value x2.5, and A1 is the normal value x2.5 or more. G categories are separated into two groups according to the mitotic rate in a high power field (x200); G1 is assigned to the tumor with 0-9/1 HPF and G2 is assigned to those with 10 or more/1 HPF. Reclassification of osteosar-coma by this modified TNM system indicated that there was a correlation between the survival rate and the stage.

In radiotherapeutic management for pediatric tumors, we have to pay more attention to confinement of higher dose to the target volume than for adult tumors, in order that the risk of untoward normal tissue complications dose not increase, such as growth retardation. Two current approaches performing in our department to match this purpose are presented, namely, perioperative brachytherapy and fractionated stereotactic radiotherapy (F-SRT). In perioperative brachytherapy for bone and soft tissue sarcoma, plastic guide tubes for introducing radioactive sources are placed in the residual tumor bed or at the margins during the surgery, and patients are treated by high-dose-rate brachytherapy after surgery. Patients are not restricted in radioprotective area, and the overall treatment period is short enough. F-SRT is used either as the boost of conventional brain radiotherapy in primary brain neoplasms, or as hypofractionated F-SRT for control of metastatic brain tumors, with nearly perfect local control and maintenance of good quality of life. F-SRT is planned in 3-dimensional fashion from computed tomography images. Easily detachable, relocatable cast made for F-SRT is useful in pediatric patients.

KEKB has been operated since December, 1998, to deliver B ¯ B pairs for a physics detector. In this paper,we describe the commissioning procedure of KEKB.

Imaging results in patients with high-grade osteosarcoma of the extremities were reviewed to determine whether scintigraphic appearance correlated with histologic response to preoperative chemotherapy.Histologically, the percent tumor necrosis in specimens from 30 patients were classified into three grades: grade 1 = necrosis less than 60%, grade 2 = 60%-89% necrosis and grade 3 = diffuse necrosis greater than 90% based upon whole transverse sections. Scintigraphically, we analyzed 201TI uptake before and after preoperative chemotherapy. The changes in the tumor-to-background ratio were defined by an alteration ratio.Of the 11 patients with a grade 1 response, the ratio showed -67.1% +/- 45.4% (mean +/- s.d.). Of the 9 patients with a grade 2 response, the ratio showed 37.9% +/- 29.9% of the 10 patients with a grade 3 response the ratio showed 105.5% +/- 12.4%. The ratios correlated well with the histologic grades (p0.0001; analysis of variance).Thallium-201 scintigraphy accurately assesses the effect of chemotherapy on osteosarcoma.

After medical sphincter dilation using sud-lingual nitroglycerin, endoscopic removal of common bile duct stones in 15 patients was carried out. Complete stone removal was obtained in 14 of 15 patients. Only 0.3 mg to 0.6 mg nitroglycerin was needed to give an enough dilation of the orifice for cannulating the basket catheter into the bile duct. Mechanical lithotriptor was smoothly cannulated in one patient because of possible impaction. Blood pressure was dropped transiently in one patient by nitroglycerin, however, the general condition of the patient was stable. This procedure is safe, easy and effective in preserving sphincter function. Acute cholecystitis, a common complication of persistent gallbladder stone after endoscopic sphincterotomy, may be avoided by employing this method. More clinical studies, on long term and in a large scale of patients, are necessary to reduce complications that usually occur after sphincterotomy.

An 18-year-old woman presented with coughing, fever, progressive dyspnea, and diffuse infiltrates on the chest X-ray film. Analysis of bronchoalveolar lavage fluid showed 73% eosinophils. Acute eosinophilic pneumonia was diagnosed. Methylprenisolone, 1 g per day was given for three days and her condition improved dramatically. No relapse was observed. Analysis of bronchoalveolar lavage fluid also showed lymphocytosis, abnormally high concentrations of ECP, GM-CSF, IL-5 and sICAM-1, and hypersegmentation of eosinophil nuclei. After steroid treatment almost all these findings returned to normal; only lymphocytosis remained. Precipitating antibodies against four kinds of fungi, including Trichoderma viridae, were noted in the serum, but the environmental provocation test was negative and those fungi were not detected in the environmental culture growth. Comparison of bronchoalveolar lavage findings obtained before and after steroid treatment can provide information on the mechanism of eosinophil accumulation in the lung. This case also draws attention to the relationship between acute and chronic eosinophilic pneumonia.

The criteria for the evaluation of the treatment on primary bone sarcoma proposed by the Musculoskeletal Tumor Committee of the Japanese Orthopaedic Association (JOA) were accepted in 1993 by the Joint Committee for Cancer Therapy of the Japan Society for Cancer Therapy. The responses to treatment are classified as a complete response (CR), a partial response (PR), no change (NC), or as progressive disease (PD). It is a requirement that the condition of CR, PR, or NC continues for at least 4 weeks. The radiographical criteria are as follows: CR, the disappearance of the intramedullary lesions and the bone trabeculae recovering a normal appearance; PR, the circumscription of the extraosseous tumor and an appearance of sclerotic foci within the intramedullary lesion; NC, no changes noted in the extraosseous and intramedullary lesions; PD, an increase in the extraosseous or intramedullary lesion and/or the appearance of new lesions. Histopathological criteria are as follows: CR, no tumor cells appearing viable in any of the histologic sections; PR, greater than 90% tumor necrosis attributable to treatment; NC, 50 to 90% tumor necrosis and other secondary changes attributable to treatment; PD, less than 50% tumor necrosis. Responses in the clinical signs and symptoms including tumor size (or circumference of the extremities at the site of the tumor), pain and local heat are also graded as follows: PR, subsiding symptoms and/or decrease in the tumor size; NC, neither exacerbation nor decrease in the symptoms and no change in size; PD, the exacerbation of symptoms or an increase in size. Additionally, the serum alkaline phosphatase level can be used for evaluating the effect of the treatment on the osteosarcoma. The extent of the response to preoperative chemotherapy is a powerful predictor of patient survival.