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The General Antiparticle Spectrometer (GAPS) experiment is a balloon payload designed to measure low-energy cosmic antinuclei during at least three $\sim$35-day Antarctic flights, with the first flight planned for December, 2022. With its large geometric acceptance and novel exotic atom-based particle identification method, GAPS will detect $\sim$1000 antiprotons per flight, producing a precision cosmic antiproton spectrum in the kinetic energy range of $0.03 - 0.23$ GeV/$n$ at float altitude (corresponding to $0.085- 0.30$ GeV/$n$ at the top of the atmosphere). With these high statistics in a measurement extending to lower energy than any previous experiment, and with orthogonal sources of systematic uncertainty compared to measurements made using traditional magnetic spectrometer techniques, the GAPS antiproton measurement will be sensitive to physics including dark matter annihilation, primordial black hole evaporation, and cosmic ray propagation. The antiproton measurement will also validate the GAPS exotic atom technique for the antideuteron and antihelium rare-event searches and provide insight into models of cosmic particle attenuation and production in the atmosphere. This contribution demonstrates the GAPS sensitivity to antiprotons using a full instrument simulation, event reconstruction, and solar and atmospheric effects.

Through advanced experimental techniques on CrI$_{3}$ single crystals, we derive a previously not discussed pressure-temperature phase diagram. We find that $T_{c}$ increases to $\sim$ 66\,K with pressure up to $\sim$ 3\,GPa followed by a decrease to $\sim$ 10\,K at 21.2\,GPa. The experimental results are reproduced by theoretical calculations based on density functional theory where electron-electron interactions are treated by a static on-site Hubbard U on Cr 3$d$ orbitals. The origin of the pressure induced reduction of the ordering temperature is associated with a decrease of the calculated bond angle, from 95$^{\circ}$ at ambient pressure to $\sim$ 85$^{\circ}$ at 25\,GPa. Above 22\,GPa, the magnetically ordered state is essentially quenched, possibly driving the system to a Kitaev spin-liquid state at low temperature, thereby opening up the possibility of further exploration of long-range quantum entanglement between spins. The pressure-induced semiconductor-to-metal phase transition was revealed by high-pressure resistivity that is accompanied by a transition from a robust ferromagnetic state to gradually more dominating anti-ferromagnetic interactions and was consistent with theoretical modeling.

Low-energy cosmic ray antideuterons ($

The General Antiparticle Spectrometer (GAPS) is an upcoming balloon mission to measure low-energy cosmic-ray antinuclei during at least three ~35-day Antarctic flights. With its large geometric acceptance and novel exotic atom-based particle identification, GAPS will detect ~500 cosmic antiprotons per flight and produce a precision cosmic antiproton spectrum in the kinetic energy range of ~0.07-0.21 GeV/n at the top of the atmosphere. With these high statistics extending to lower energies than any previous experiment, and with complementary sources of experimental uncertainty compared to traditional magnetic spectrometers, the GAPS antiproton measurement will be sensitive to dark matter, primordial black holes, and cosmic ray propagation. The antiproton measurement will also validate the GAPS antinucleus identification technique for the antideuteron and antihelium rare-event searches. This analysis demonstrates the GAPS sensitivity to cosmic-ray antiprotons using a full instrument simulation and event reconstruction, and including solar and atmospheric effects., Comment: 11 pages, 9 figures, revision updated with addition of Figure 5 and slight changes in the text to match the version accepted by Astroparticle Physics

The length of tumour-vein contact between the portal-superior mesenteric vein (PV/SMV) and pancreatic head cancer, and its relationship to prognosis in patients undergoing pancreatic surgery, remains controversial.Patients diagnosed with pancreatic head cancer who were eligible for pancreatoduodenectomy between October 2002 and December 2016 were analysed. The PV/SMV contact was assessed retrospectively on CT. Using the minimum P value approach based on overall survival after surgery, the optimal cut-off value for tumour-vein contact length was identified.Among 491 patients included, 462 underwent pancreatoduodenectomy for pancreatic head cancer. PV/SMV contact with the tumour was detected on preoperative CT in 248 patients (53·7 per cent). Overall survival of patients with PV/SMV contact exceeding 20 mm was significantly worse than that of patients with a contact length of 20 mm or less (median survival time (MST) 23·3 versus 39·3 months; P = 0·012). Multivariable analysis identified PV/SMV contact longer than 20 mm as an independent predictor of poor survival, whereas PV/SMV contact greater than 180° was not a predictive factor. Among patients with a PV/SMV contact length exceeding 20 mm on pretreatment CT, those receiving neoadjuvant therapy had significantly better overall survival than patients who had upfront surgery (MST not reached versus 21·6 months; P = 0·002).The length of PV/SMV contact predicts survival, and may be used to suggest a role for neoadjuvant therapy to improve prognosis.El valor pronóstico de la longitud del contacto del tumor de la cabeza pancreática con las venas porta y mesentérica superior (portal-superior mesenteric vein, PV/SMV) en los pacientes sometidos a cirugía pancreática sigue siendo un tema controvertido. MÉTODOS: Se analizaron los pacientes diagnosticados de un cáncer de la cabeza pancreática a los que se realizó una duodenopancreatectomía cefálica entre octubre de 2002 y diciembre de 2016. El contacto tumoral con la PV/SMV se evaluó de forma retrospectiva mediante tomografía computarizada (TC). Se identificó el valor de corte óptimo para la longitud del contacto tumoral con la PV/SMV, utilizando el valor mínimo de la P basado en la supervivencia global (overall survival, OS) después de la cirugía.De 491 pacientes incluidos, en 462 pacientes se realizó una duodenopancreatectomía cefálica por cáncer de la cabeza de páncreas. En la TC preoperatoria, se detectó contacto tumoral con la PV/SMV en 248 (53,7%) pacientes. La OS de los pacientes en los que el contacto del tumor con la PV/SMV fue 20 mm fue significativamente peor que en aquellos cuyo contacto fue ≤ 20 mm (mediana de supervivencia (median survival time, MST) 23,3 versus 39,3 meses; P = 0,012). En un análisis multivariado se identificó el contacto tumoral-PV/SMV 20 mm como un factor independiente predictor de mala supervivencia, pero el contacto tumor-PV/SMV 180° no fue un factor pronóstico. En los pacientes en los que el contacto tumor-PV/SMV fue 20 mm en el TC preoperatorio, la OS en aquellos que recibieron tratamiento neoadyuvante fue significativamente mejor en comparación con los pacientes tratados directamente con cirugía (MST, no alcanzada versus 21,6 meses, P = 0,002). Conclusión La longitud del contacto tumoral con la PV/SMV predice la supervivencia, por lo cual dicha longitud podría jugar un papel en la indicación de tratamiento neoadyuvante para mejorar el pronóstico.

The differential cross sections of the Σ^{-}p→Λn reaction were measured accurately for the Σ^{-} momentum (p_{Σ}) ranging from 470 to 650 MeV/c at the J-PARC Hadron Experimental Facility. Precise angular information about the Σ^{-}p→Λn reaction was obtained for the first time by detecting approximately 100 reaction events at each angular step of Δcosθ=0.1. The obtained differential cross sections show a slightly forward-peaking structure in the measured momentum regions. The cross sections integrated for -0.7≤cosθ≤1.0 were obtained as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst) mb for 470p_{Σ}(MeV/c)550 and 550p_{Σ}(MeV/c)650, respectively. These results show a drastic improvement compared with past measurements of the hyperon-proton scattering experiments. They will play essential roles in updating the theoretical models of the baryon-baryon interactions.

We have investigated a prototype triggerless data acquisition (DAQ) system for charmed-baryon spectroscopy at J-PARC. A special time-to-digital converter (TDC) dedicated to continuous timing measurement without any external trigger was developed. A high dynamic range of the order of 1010 for the timing measurement was realized by introducing the heartbeat method, which periodically generates a delimiter datum. DAQ software receiving and filtering the data stream from the TDCs was also developed based on a message-queue application programming interface (API), FairMQ. We tested the prototype DAQ system with detectors using electrons and positrons converted from a bremsstrahlung photon beam with a rate condition of up to 1.9 MHz/1-mm detector segment. The DAQ received a 5.4 Gbps data stream from six TDCs and merged them to a complete data set. After sorting a certain portion of the data, the software searched for a set of corresponding data fragments in response to the penetration of a positron or electron using time separation between detector hits in the time axis and removed unnecessary hits. Around 25 GB RAM and 25 CPU threads were required for the online computing power under the test conditions. No silent data drop in the DAQ software was observed.

The General Antiparticle Spectrometer (GAPS) is the first experiment optimized to identify low energy (

Background Hepatectomy with vascular resection (VR) for perihilar cholangiocarcinoma (PHCC) is a challenging procedure. However, only a few reports on this procedure have been published and its clinical significance has not been fully evaluated. Methods Patients undergoing surgical resection for PHCC from 2002–2017 were studied. The surgical outcomes of VR and non-VR groups were compared. Results Some 238 patients were included. VR was performed in 85 patients. The resected vessels were hepatic artery alone (31 patients), portal vein alone (37 patients) or both (17 patients). The morbidity rates were almost the same in the VR (49.4 per cent) and non-VR (43.8 per cent) groups (P = 0.404). The mortality rates of VR (3.5 per cent) and non-VR (3.3 per cent) were also comparable (P > 0.999). The median survival time (MST) was 45 months in the non-VR group and 36 months in VR group (P = 0.124). Among patients in whom tumour involvement was suspected on preoperative imaging and whose carbohydrate antigen 19-9 (CA19-9) value was 37 U/ml or less, MST in the VR group was significantly longer than that in the non-VR group (50 versus 34 months, P = 0.017). In contrast, when the CA19-9 value was greater than 37 U/ml, MST of the VR and non-VR groups was comparable (28 versus 29 months, P = 0.520). Conclusion Hepatectomy with VR for PHCC can be performed in a highly specialized hepatobiliary centre with equivalent short- and long-term outcomes to hepatectomy without VR., Major hepatectomy with vascular (hepatic artery and/or portal vein) resection and reconstruction was performed in 85 consecutive patients with advanced perihilar cholangiocarcinoma. This surgery is technically demanding but can be performed with equivalent short- and long-term outcomes in a highly specialized hepatobiliary centre.

A new hyperon-proton scattering experiment, dubbed J-PARC E40, was performed to measure differential cross sections of the Σ+p, Σ−p elastic scatterings and the Σ−p → Λn scattering by identifying a lot of Σ particles in the momentum ranging from 0.4 to 0.8 GeV/c produced by the π±p → K+Σ± reactions. We successfully measured the differential cross sections of these three channels with a drastically improved accuracy with a fine angular step. These new data will become important experimental constraints to improve the theories of the two-body baryon-baryon interactions. Following this success, we proposed a new experiment to measure the differential cross sections and spin observables by using a highly polarized Λ beam for providing quantitative information on the ΛN interaction. The results of three Σp channels and future prospects of the Λp scattering experiment are described.

Background Non-anatomical liver resection (NAR) and radiofrequency ablation (RFA) are treatment options for early-stage hepatocellular carcinoma (HCC). The aim was to compare the outcomes of NAR and RFA for HCC in patients with three or fewer tumour nodules, each measuring not more than 3 cm in maximum diameter. Methods Eligible patients undergoing NAR or RFA with curative intent between September 2002 and December 2014 were identified. A propensity score-matching analysis was performed to reduce bias, and outcomes in these patients were analysed. Results From a total of 199 patients, 1:1 propensity score matching identified 70 matched pairs. Patients having NAR had a longer hospital stay (median 10 days versus 4 days for those who had RFA; P < 0·001) and a higher morbidity rate (24 versus 10 per cent respectively; P = 0·042). Patients who had NAR had slightly better recurrence-free survival but this failed to reach statistical significance in univariable analysis (P = 0·064). There was no significant difference in overall survival between the two groups (P = 0·475). RFA was identified as an independent risk factor for recurrence-free survival (hazard ratio (HR) 1·57; P = 0·041) in multivariable analysis. Local recurrence was significantly more common in patients receiving RFA (23 versus 1 per cent; P < 0·001). Conclusion RFA was an independent risk factor for shorter recurrence-free survival, with a significantly higher local recurrence rate than NAR. Despite these differences, overall survival was not affected.

International audience; A part of the experiment was performed in 2018 and 2019 in J-PARC. As a result of analyzing the collected data, the \(\Sigma ^{ - }\) production and the \(\Sigma ^{ - }p\) scattering reaction have been identified. It means that our new measurement and analysis method are successfully working well. Analysis for deriving the differential cross section of the \(\Sigma p\) scattering is on going.

International audience; The \(\pi ^{ - }p \to K^{0}\Lambda \) reaction is an important elementary process to produce \(\Lambda \) from a proton target and is a key for a \(\Lambda p\) scattering experiment where the momentum of \(\Lambda \) should be tagged from the missing momentum of the \((\pi ^{ - },K^{0})\) reaction. However, the \((\pi ^{ - },K^{0})\) spectroscopy method has not been established yet due to the difficulty of the K^0 detection. Therefore, we have proposed a new K^0 detection method where \(\pi ^{ + }\) and \(i^{ - }\) from the K^0 decay are measured by a forward magnetic spectrometer and a detector cluster surrounding the target, respectively. The feasibility of the K^0 detection method was confirmed by analyzing the J-PARC E40 data taken with such a detector system. In the analysis, \(\Lambda \)’s were successfully identified in the missing mass spectrum of the \(\pi ^{ - }p \to K^{0}X\) reaction.

International audience; Although more detailed analysis for deriving the cross section of \(\Sigma p\) scattering is necessary to derive the cross section of \(\Sigma p\) scattering, we have confirmed that CFT has enough angular resolution of tracking and energy resolution in order for the identification of the scattering events and particles.

International audience; J-PARC E40 aims to measure the differential cross sections of the Σ^±p elastic scatterings and the Σ^−p → Λn conversion. A clear peak of Σ^− was observed in a missing mass spectrum of the π^−p → K^+X reaction and recoil protons from the πp elastic scattering were successfully observed in the data taken in the summer 2018. The rest of data taking is coming in the spring 2019.

A high statistics ∑p scattering experiment has been performed at the K1.8 beamline in the J-PARC Hadron Experimental Facility. Data for momentum-tagged ∑− beam running in a liquid hydrogen target were accumulated by detecting the π − p → K + ∑ − reaction with a high intensity π− beam of 20 M/spill. The number of the Σ− beam was about 1.7 × 107 in total. The ∑−ρ elastic scattering and the ∑−p → Λn inelastic scattering events were successfully observed with about 100 times larger statistics than that in past experiments.

We examined the spatial distributions of

Fast excitatory transmission in the mammalian central nervous system is mediated by AMPA-type glutamate receptors. The tetrameric AMPA receptor complexes are composed of four subunits, GluR1-4. The GluR4 subunit is highly expressed in the cerebellum and the early postnatal hippocampus and is thought to be involved in synaptic plasticity and the development of functional neural circuitry through the recruitment of other AMPA receptor subunits. Previously, we reported an association of the human GluR4 gene (GRIA4) with schizophrenia. To examine the role of the GluR4 subunit in the higher brain function, we generated GluR4 knockout mice and conducted electrophysiological and behavioural analyses. The mutant mice showed normal long-term potentiation (LTP) in the CA1 region of the hippocampus. The GluR4 knockout mice showed mildly improved spatial working memory in the T-maze test. Although the retention of spatial reference memory was intact in the mutant mice, the acquisition of spatial reference memory was impaired in the Barnes circular maze test. The GluR4 knockout mice showed impaired prepulse inhibition. These results suggest the involvement of the GluR4 subunit in cognitive function.

We report two patients with mediastinal abscess developing after surgery for oesophageal cancer who were treated by percutaneous drainage using a unified CT and angiography system, which allows both CT and fluoroscopy to be conducted with the patient on the same bed. Fine needle puncture is performed under CT guidance and this needle is used as a tandem for insertion of the drainage needle under fluoroscopic guidance, making safe puncture possible whilst confirming the position of the needle tip. Moreover, contrast medium can be injected from the drainage tube, allowing the extent of the abscess cavity to be determined by fluoroscopy and CT, thereby making accurate drainage possible.

We report two cases in which hepatic arterial occlusion developed soon after percutaneous catheter placement for hepatic arterial infusion chemotherapy in malignant hepatic neoplasms. A replaced hepatic artery and a proper hepatic artery, respectively, became occluded in these cases. In both, because the tip of a side-holed catheter for arterial infusion was fixed in place, we performed recanalization without removing the indwelling catheter. Despite the presence of the catheter, a stent could be inserted into the occluded portion of the hepatic artery. Recanalization of the hepatic artery was achieved with stent placement, and continuation of hepatic arterial infusion became possible.

Effect of reaction temperature on hydrotreatment of a recycle solvent in the NEDOL coal liquefaction process was studied from the data obtained by the operation of a 150 t/d pilot plant. Hydrotreatment of the recycle solvent was carried out under a hydrogen pressure of 100 kg/cm 2 G over Ni–Mo/Al 2 O 3 catalyst in a fixed bed reactor. As the reaction temperature increased from 290 to 330°C, the hydrogen gas consumption increased from 0.4 to 1.0 wt%. About 50% of consumed hydrogen was utilized for the hydrogenation of aromatic rings in the recycle solvent, and the rest for the removal of nitrogen and oxygen from the recycle solvent, and for cracking of the recycle solvent. Among aromatic compounds contained in the recycle solvent, two-ring aromatics and hydroaromatics and their derivatives (aromatics of naphthalene type) shared the largest fraction. The aromatics of the naphthalene type underwent hydrogenation faster than those of the phenanthrene type, the anthracene type, and the pyrene type. Under the reaction conditions examined, excess hydrogenation of the aromatics of the naphthalene type to form perhydrogenated compounds (naphthenes) did not take place so extensively; i.e. tetrahydronaphthalenes formed much more than decahydronaphthalenes.

Background: Preoperative portal vein embolization (PVE) is performed to enhance the future remnant liver function (FRLF) and volume (FRLV). However, the volume of the nonembolized liver does not increase enough in some patients, which results in an insufficient FRLF. The aim of this study was to evaluate the predictors of insufficient FRLF after PVE for extended hepatectomy. Methods: This retrospective study included 172 patients (107 patients with cholangiocarcinoma, 40 patients with metastatic liver cancer and 25 patients with hepatocellular carcinoma) who underwent PVE before extended hepatectomy. The total liver function was evaluated by measuring the indocyanine green plasma clearance rate (KICG). Computed tomography volumetry was conducted to evaluate the total liver volume and FRLV. The KICG of the future remnant liver (remK) was calculated using the following formula: KICG × FRLV/total liver volume. The safety margin for hepatectomy was set at remK after PVE (post-PVE remK) ≥0.05. Results: One hundred and twenty-three patients with a post-PVE remK level of >0.05 underwent hepatectomy without postoperative liver failure [sufficient liver regeneration (SLR) group], and 9 patients with a post-PVE remK level of Conclusions: The patients in the ILR group did not achieve SLR after PVE due to a significant decrease in the KICG and an insufficient increase in %FRLV. A pre-PVE remK value of

This paper describes a high speed and area effective multiplier-accumulator for an embedded RISC processor. The point of architecture is to utilize a full adder array and the Booth's encoder twice in a cycle. The multiplier-accumulator executes one multiply-add operation (32 b multiplication followed by 64 b addition) per cycle at 56.5 MHz. The area is 2.35 mm/sup 2/ with 0.4 /spl mu/m CMOS technology.

Surimi was prepared with channel catfish mince recovered from fillet frames. The deboned meat was washed once, twice, or three times with water for surimi processing. Unwashed mince was also blended with cryoprotectants for surimi processing. Heat-induced gels were prepared using washed or unwashed catfish surimi with or without starch. Results indicated no differences (P>0.05) in textural properties and Hunter color values due to number of washes in those gels prepared with washed surimi. Differences (P

During attempted oesophageal stent placement in a patient with cervical oesophageal cancer in whom swallowing of even saliva was impossible, transoral access to the cervical oesophagus was unsuccessful. Under ultrasound and fluoroscopy guidance, percutaneous gastric puncture was performed, and using an angiographic catheter and guidewire, access to the oesophagus by a retrograde transgastric route was successfully achieved. The obstructed segment of the oesophagus was traversed. It was then possible to pull the guidewire through the mouth and place an oesophageal stent via an antegrade approach.

Lubricant characteristics of dual lubricant layers, which consist of a first-lubricant bonded layer and second-lubricant mobile layer, were studied. The interface durability is evaluated by a pin-on-disk test. The spin-migration characteristic is evaluated based on the change in thickness of layers after disk spinning. The mobility is estimated from spreading profiles from the lubricant step. Dual lubricant layers , which consists of Z-dol as a mobile layer and Z-tetraol or AM as a bonded layer, shows high mobility, high interface durability, and low spin-migration performance. It is considered that these characteristics can be attributed to higher interaction between the bonded lubricant and the mobile lubricant due to strong polar end groups of the bonded lubricant.

The effect of blood volume contraction induced by a 4-week regimen of spironolactone (100 mg/day) or furosemide (40 mg/day) on the hepatic venous pressure gradient (HVPG), an indicator of portal hypertension, was evaluated in patients with cirrhosis and no ascites. In the spironolactone group (n = 15), HVPG decreased significantly from 16.5 +/- 0.9 mmHg (mean +/- S.E.M.) to 12.9 +/- 1.0 mmHg (P0.005) and total blood volume contracted significantly from 4338 +/- 231 ml to 4006 +/- 203 ml (n = 14, P0.01). Although the HVPG changes did not correlate significantly with changes in measured total blood volume or in simultaneously determined systemic haemodynamics, a significant inverse correlation (r = -0.74, P0.01, n = 12) was found between the HVPG change and posttreatment plasma aldosterone levels, attesting to the effectiveness of spironolactone therapy in lowering HVPG. In the furosemide group (n = 10), neither HVPG (13.7 +/- 0.3 mmHg vs. 13.6 +/- 0.9 mmHg) nor total blood volume (4961 +/- 153 ml vs. 4964 +/- 162 ml) declined significantly. These results show that long-term administration of spironolactone to patients with cirrhosis and no ascites produced a significant reduction in HVPG that may have been due to gradual, sustained volume contraction. Thus, spironolactone may prove to be an effective treatment for portal hypertension in cirrhosis without ascites.

The effect of (D-Ala, D-Leu) enkephalin (DADLE) on the binding of GTP in hippocampal preparations was studied. It was observed that treatment of hippocampal slices with 10 −5 −5×10 −5 M DADLE followed by the preparation of membrane fractions reduced the binding of 35 S-GTP-γ-S. There was no change in the affinity of the binding. This decrease of 35 S-GTP-γ-S binding was reversed when 5×10 −5 M naltrindole was included. The effect was not observed when the membrane fractions were incubated with DADLE. Photoaffinity labeling with the use of 32 P P3-(4-azidoanilido) -P1 5' -GTP followed by sodium dodecyl sulfate-polycrylamide gel electrophoresis and autoradiography revealed the incorporation of radioactivity into molecular mass of the 43 kDa and 33–34 kDa proteins. 32 P Photolabeling of both the 43 kDa and 33–34 kDa bands decreased following treatment of hippocampal slices with 10 −4 M DADLE. These results suggested that DADLE reduces the GDP-GTP exchange in hippocampal membranes.

We report on recent work on the General Antiparticle Spectrometer Experiment (GAPS). GAPS is a balloon‐based search for antideuterons generated in the annihilation of weakly interacting massive particles. Antideuterons provide an extremely clean signature of dark matter. It is difficult to produce backgrounds that mimic the annihilation antideuterons. GAPS consists of a time‐of‐flight system combined with a multi‐layer particle tracker composed of pixellated Si(Li) detectors. When an antideuteron enters the telescope it slows down and is captured in a silicon atom. The resultant exotic atom deexcites with the emission of multiple atomic X‐rays, and a shower of subatomic particles when the antideuteron enters the nucleus from the atomic ground state. The atomic X‐rays, TOF, depth sensing and charged particle multiplicity provide an extremely stringent particle identification capability. GAPS can improve the current BESS experiment antideuteron limits by more than three orders of magnitude and access a large part of beyond standard model physics parameter spaces.

Two-dimensional radiation by a relativistic sheet electron beam propagating parallel to a reflection grating composed of a sinusoidally corrugated conducting surface is studied rigorously using the mode-matching method. Accurate dispersion curves for the eigenmodes that govern the Smith-Purcell radiation and the instability of the electromagnetic surface wave are presented. The imaginary parts of the eigenwavenumber and eigenfrequency give the leakage coefficient of space-charge waves and the growth rate of electromagnetic surface waves. Their dependences on the dimensions of the radiating structure are discussed. Optimum parameters for achieving the maximum leakage coefficient and the growth rate are determined. The method is general and can be applied to any two-dimensional system of electron beam coupled to an open periodic structure of arbitrary profile. >

The Geographical Survey Institute of Japan has installed a network of about 1000 dual-frequency GPS receivers in Japan with their mutual distance of about 25 km. Phases and pseudo ranges of dual-frequency GPS signals are recorded every 30 s. The dense distribution of the GPS receivers allows us to reveal two-dimensional structures of the ionospheric plasma density irregularities with scale sizes of the order of several kilometers. We analyzed TEC data obtained from the GPS network of Japan in 2000. It was found that the irregularity characteristics over Japan depended on latitude. The results are as follows: (1) at the northern part, the irregularities appeared only during geomagnetic storms. (2) At the middle part, they had the most frequent occurrence in summer nighttime and were usually accompanied by Medium-Scale Traveling Ionospheric Disturbances (MSTID). (3) At the southern part, they were associated with the equatorial plasma bubbles and their occurrences were highest in the equinoctial nighttime.

Background: The role of positron emission tomography with the glucose analogue [18F] fluoro-2-deoxy-D-glucose (FDG-PET) in the initial staging of disease in patients with primary colorectal cancer (CRC) has not been adequately assessed. Aims: To evaluate the additional value of FDG-PET as a staging modality, complementary to routine multidetector row computed tomography (MDCT) in patients with CRC. Methods: Forty four patients with CRC underwent preoperative MDCT and FDG-PET. The accuracy of intraoperative macroscopic staging was also investigated compared with histopathological diagnosis. All FDG-PET images were evaluated with respect to detectability of the primary tumour, lymph node involvement, and distant metastases. Both MDCT and FDG-PET diagnoses and treatment plan were compared with surgical and histopathological results. Results: Thirty seven patients underwent surgery. Tumour detection rate was 95% (42/44) for MDCT, 100% (44/44) for FDG-PET, and 100% (37/37) for intraoperative macroscopic diagnosis. Pathological diagnosis of T factor was T1 in five, T2 in four, T3 in 24, and T4 in four cases. Concordance rate with pathological findings of T factor was 57% (21/37) for MDCT and 62% (23/37) for macroscopic diagnosis. Lymph node involvement was pathologically positive in 19 cases. Regarding N factor, overall accuracy was 62% (23/37) for MDCT, 59% (22/37) for FDG-PET, and 70% (26/37) for macroscopic diagnosis. For all 44 patients, FDG-PET findings resulted in treatment changes in only one (2%) patient. Conclusion: FDG-PET is not superior to routine MDCT in the initial staging of primary CRC.

The Shawan River will be the focal point in the development of the Panyu District, the southern-most district of Guangzhou City in the Guangdong Province of South China. In this research, through the use of two scenarios, the future water quality of the Shawan River was predicted with relation to changes in the water quantity utilized to fuel industrial and domestic development. The worst-case scenario used, simulated the situation if no wastewater treatment was employed, and the best-case scenario simulated the situation if 90% of the pollution load was removed. The period of simulation was for the years 2020 and 2050. Three flowrates were used in the evaluation, those of: the 90% probability of the month of lowest flow (37.2 m3/s); and the range of flowrates within the low flow period, that is, the dry season from November to February (307 and 432 m3/s). Subsequently, two countermeasures (industrial and domestic water savings)--sustainable initiatives--were nested within the two scenarios to ascertain improvements in water quality as a direct result of reduction in water quantity used. The industrial water saving countermeasure showed the greatest improvement in water quality. For the 90% probability of lowest flow for the worst-case scenario, this countermeasure equated to a 63% decrease in BOD. For the low flow period flowrates the background concentration of pollutants was more influential than improvements imparted by the countermeasures to the future predicted water quality. It was recommended that industrial countermeasures be used that take into account water saving, water recycling, the use of brackish water for cooling, and the implementation of economic pricing initiatives. Also that inter-district governmental policy initiatives be introduced to prevent upstream pollution from influencing downstream proposals, further enhancing sustainable water management of the Shawan River.

The rapid growth of the Internet impacts ATM networks to be furnished with IP handling capability. This paper discusses networking issues for IP and ATM integration. First, it considers function allocation at the boundary of an ATM backbone network and the Internet. As a result, the paper explains the necessity of built-in IP handling capability in an ATM switching system, and summarizes functional requirements for the system architecture. According to the discussion, the authors propose a system architecture for IP/ATM integration in the ATM switching system. The implementation of the proposed architecture is evaluated, and the wire-speed IP handling capability in the ATM switch is confirmed.

The authors investigate Smith-Purcell radiation due to a relativistic sheet-electron beam propagating parallel to a reflection grating composed of sinusoidally corrugated conducting surface. A self-consistent analysis of the method and instability is developed using the mode-matching method. The precise numerical results for the dispersion relation of eigenmodes supported by the two-dimensional system are presented over the frequency range from the spontaneous emission regime to the stimulated emission regime. >

The authors propose a parallel ATOM (asynchronous transfer mode output modular) switch architecture, capable of handling multi-gigabit per second lines. It is composed of distributors, a number of switch planes, and resequencers. A simple resequencing method is also proposed to keep sequence integrity for cells sent out from different switch planes. It is shown that the memory access speed requirement can be reduced dramatically, as the number of switch planes increases. With this architecture, for example, a 9.6 Gb/s per line 32 by 32 ATM switch can be achieved using 70 Mb/s BiCMOS technologies. Performance evaluations by computer simulation show that additional delay and buffer memories for resequencing are much smaller than for conventional methods, and that they pose no practical problem. >

In this paper, an access network controller for ADSL (asymmetric digital subscriber line) is described. It consists of a VR4120 MPU core, a system controller, an Ethernet controller, an ATM (asynchronous transfer mode) cell processor, a USB (universal serial bus interface) controller, and other blocks. This controller, along with ADSL PHY devices, can provide a total solution for ADSL modem and ADSL router.

Bare stents are commonly used for the treatment of malignant vena cava stenoses. However, the therapeutic effect of treatment using bare stents for cases with intraluminal tumor invasion is not satisfactory. We report a case with severe obstruction of the superior vena cava caused by tumor invasion of mediastinal lymph node metastases from colon cancer, which was successfully treated by the recanalization of superior vena cava using a polytetrafluoroethylene-covered Z stent. The covered stent could not be fully expanded at first, and re-obstruction developed at the stented site due to thrombus formation soon after stenting. So, the additional balloon dilatation made the stent expend fully on another day of stenting. After the balloon dilatation blood flow improved immediately and the clinical symptoms associated with the superior vena cava obstruction resolved. Thereafter no symptomatic recurrence has been observed in 12 months of follow-up period.

Portopulmonary hypertension is a condition with a poor prognosis, which is defined as precapillary pulmonary hypertension complicating portal hypertension mainly due to cirrhosis of various etiologies. A mean pulmonary arterial pressure greater than 25 mmHg at rest with a pulmonary capillary wedge pressure less than 15 mmHg and a pulmonary vascular resistance greater than 120 dynes.sec.cm-5, in the setting of the presence of portosystemic shunting has been proposed as hemodynamic criteria for portopulmonary hypertension. Prevalence of pulmonary hypertension ascertained by right cardiac catheterization was 2% among patients with cirrhosis, and reached to 4% particularly among candidates for liver transplantation. Hyperdynamic systemic circulation seen commonly in patients with cirrhosis appeared to be normalized by complication of pulmonary hypertension with a contraction of circulating plasma volume. Long term treatment by epoprostenol administration or nitric oxide inhalation could induce a gradual decline in pulmonary arterial pressure in patients with poor response to acute vasodilator administration.

We report two cases in which hepatic arterial occlusion developed soon after percutaneous catheter placement for hepatic arterial infusion chemotherapy in malignant hepatic neoplasms. A replaced hepatic artery and a proper hepatic artery, respectively, became occluded in these cases. In both, because the tip of a side-holed catheter for arterial infusion was fixed in place, we performed recanalization without removing the indwelling catheter. Despite the presence of the catheter, a stent could be inserted into the occluded portion of the hepatic artery. Recanalization of the hepatic artery was achieved with stent placement, and continuation of hepatic arterial infusion became possible.