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The titanium Greenfield filter (TGF) is widely accepted for its efficacy, high patency, and low complication rate. Between November 1998 and April 2000, six patients underwent placement of titanium Greenfield filters at Tokoro Memorial Hospital. Three patients were at high risk for pulmonary embolism (PE), two were at risk for anticoagulation therapy, and, one had a proven PE. One patient died 9 months after filter insertion from a cerebral hemorrhage. Inability to pass the pelvic vein via the left femoral vein was encountered in one case at the time of placement. Plain abdominal films revealed that filter angulation (off-axis position) was confirmed in four cases. Two cases of filters were well centered in the inferior vena cava (IVC). The mean angulation was 6 ± 2.3 degrees. The plain radiographic appearance of the filter suggested asymmetric distribution of the filter struts in four cases. Four cases were examined by plain abdominal computed tomography (CT), and IVC penetration was recognized in all cases. Clinically relevant recurrent PE, cephalad or caudal migration, changes of filter span, and mechanical fracture of the strut were not recognized after TGF placement. Problems of angulation, penetration of the IVC wall, and asymmetric distribution of the filter struts were observed, but all patients were asymptomatic after filter insertion. In the future, more cases need to be studied for a better evaluation of late complications.

The Belousov-Zhabotinsky (BZ) reactions were used as typical examples of a nonlinear system far from equilibrium in connection with biological evolution. The virtual absence of gravity in the present work was given from the free-fall facility of Japan Microgravity Center (JAMIC) in Hokkaido. The reaction solution of BZ reaction was composed of bromate in sulfuric acid, 1,4-cyclohexanedione and ferroin to visualize the time development of patterns of chemical oscillations in the reaction-diffusion system. It is a bubble-free constitution in the aging of the reaction. Therefore, the setup constructed to collect image data via CCD cameras was simplified. The operation sequences of necessary devices were comprised of simple solid state relays which were started by a command from the operation room of JAMIC. The propagation profile of chemical patterns under microgravity of 10(-5) g was collected as image data for 9.8 s, and processed by a software of STM-STS2. In the aqueous solutions, propagation velocity of chemical patterns under microgravity was decreased to 80.9 % of that under normal gravity, owing to suppression of convection. On the other hand, in gel matrix, gravity did not influence the propagation velocity.

The quench current of a superconducting coil wound with a multifilamentary superconducting wire for 50-60 Hz use was measured for various frequencies by using a variable-voltage variable-frequency power supply composed of a cycloconverter or an inverter circuit to investigate characteristics of the superconducting AC coil and solve the current degradation problem. The test coil was wound by using wire containing no copper. Because of the instability of the wire, the effect of wire motion was observed, and quench current of the coil varied significantly. Generally, superconducting wires for AC use are unstable because the copper content of the wire is lower than for wires for DC or pulse use. From experimental results, it has become clear that a fixing method for wires to a bobbin keeping a good cooling condition is the key to solving the current degradation problem. >

This paper discusses a verification method for communication services on a network in which new service functions are added to only some of the network nodes. Communication networks are becoming larger, and new functions are constantly required for communication services. In a large-scale network, however it as very difficult to update all node functions simultaneously. In this case, in a single network there will be nodes that have both new and existing functions and other nodes having only existing functions. This situation might result in illegal actions in communications between functionally updated nodes and non-updated nodes. We clarify the fundamental properties of illegal actions, present an algorithm for detecting them and show that the algorithm is practical enough from the viewpoint of the order of complexity. >

Endoscopic transthoracic sympathectomy (ETS) is an efficient, safe, minimally invasive procedure, and requires only a short period of hospitalization. We performed bilateral ETS using a thoracoscope 2 mm in diameter. We performed 120 ETS for the treatment of palmar hyperhidrosis from August 1997 to April 2000. The patient was placed in the semi-sitting position under general anesthesia, one-lung ventilation being used; the operation was performed with 2-mm two-puncture method. The sympathetic chain could be observed through parietal pleura riding on the costovertebral junctions. A 2-mm Kirschner wire was employed as an electrode, and the second and third thoracic sympathetic chains were electro cauterized. A thoracic drain was not used. The needling sites were only 2 mm in size and could be fixed without suture. For the patient, a small scar of this size means virtually no scar. The operative times were from 11 min to 81 min in bilateral ETS. Immediately and dramatic decrease in the sweat excretion in the palms was noted in all patients. The 95% patients were highly satisfied with the results. The commonest side effects were compensatory sweating. This procedure is recommended as the method of choice for the surgical treatments of palmar hyperhidrosis.

Nine hundred and seventy-three consecutive patients were referred to our hospital for thoracotomy to treat chest diseases between January 1, 1981, and December 31, 1995. Of these patients, 20 males were readmitted within a mean of 20 months with a diagnosis of contralateral pneumothorax. Sixteen of the patients with a mean age of 28.5 years (range 16-76 years of age) had been operated on for bullous lung disease. The remaining four, with a mean age of 60.8 years (range 54-71), had been operated on for lung cancer. All of the 20 patients had received unilateral thoracotomy for lung resection. One patient had undergone pneumonectomy for lung cancer; three had undergone lobectomy; and 16 had been treated by partial lung resection. The patient who had undergone pneumonectomy was found to have contralateral pulmonary metastasis of lung cancer. In the other 19 patients, emphysematous bulla was the origin of the contralateral pneumothorax. The mean value of body mass index (BMI) of the group was 18.4 as compared to 21.7 in the patients who did not go on to develop contralateral pneumothorax, a significant difference (p0.05). In conclusion, postoperative contralateral pneumothorax was correlated to the existence of emphysematous changes of the lung and a significantly lower BMI. We conclude that patients with BMIs less than 20 may be at increased risk of developing postoperative contralateral pneumothorax.

To evaluate the influence of coronary artery disease (CAD), we reviewed 102 patients who underwent elective repair of abdominal aortic aneurysm (AAA) between 1982 and 1992. Prior to surgery, all patients underwent clinical evaluation for the presence of CAD including dipyridamole thallium scintigraphy. They were classified into the following groups: Group I (n = 66), no clinical evidence of CAD; Group II (n = 26), clinical evidence of stable CAD; Group III (n = 10), unstable CAD. Coronary angiography (CAG) was performed in group II and group III patients only. All patients in group I and group II underwent elective repair of their AAA without coronary revascularization. Eight patients in group III underwent CABG followed by elective AAA repair within two months. One of two patients who had impending ruptured AAA underwent combined CABG and AAA repair as a single operation and the other underwent AAA repair followed by CABG. One case of perioperative myocardial infarction occurred in group II, but there was no early postoperative death related to cardiac disease in group I and II. In group III, however one patient who underwent combined surgery died of low-output syndrome in the early postoperative period, no death or myocardial infarction occurred following staged operation in the other nine patients. This present results support the contention that CAG is not necessary in all AAA patients, and that they can be managed according to appropriate risk by a selective approach based upon clinical assessment of their CAD. It is also apparent that a staged operation can be performed very safely in patients with unstable CAD.

To achieve successful lung transplantation, it is essential to minimize reperfusion injury occurring as a result of metabolite accumulation during the preservation period or at the time of initial interaction of blood with constricted pulmonary vasculature. Initial reperfusion with warm crystalloid solution may be advantageous in preventing this injury.This study was designed to evaluate the effect of low-potassium (4 mmol/L) dextran (1%) solution as the initial warming solution after 6 hours of hypothermic storage. In 23 New Zealand White rabbits the lungs were flushed with low-potassium dextran solution (10 degrees C, 40 ml/kg, 600 cm H2O), excised, inflated with room air, and stored in a low-potassium dextran solution (10 degrees C) for 6 hours. After storage, the lungs were divided into two groups. Group 1 (n = 8) was reperfused with warm low potassium dextran for 4 minutes, at 37 degrees C followed by blood reperfusion for 30 minutes at 37 degrees C. Group II (n = 15) was reperfused only with blood for 30 minutes at 37 C. The mean pulmonary vascular resistance measured during cold flush and prior to storage was similar in both groups (group I = 20.0 +/- 5.9 mm Hg.sec/ml, group II = 19.3 +/- 1.9 mm Hg.sec/ml).During reperfusion, only 4 of the 15 lungs in group II maintained an acceptable (80 mm Hg) mean pulmonary artery pressure; six failed immediately. All eight lungs in group I completed the 30-minute reperfusion (p0.005). The mean pulmonary artery pressure was significantly less, and effluent oxygen tension was significantly greater in group I during reperfusion.In this experimental model, initial warm reperfusion with low-potassium dextran ameliorated the deleterious effects of reperfusion, thus providing an environment to improve lung preservation.

A rapid and significant vasodepressor effect was obtained during acute stage before and after surgery on aortic aneurysm with continuous antihypertensive therapy using nicardipine hydrochloride. Twenty patients were treated; 6 patients had an acute dissecting aneurysm of the aorta, 8 were postoperative cases following resection of the thoracic aortic aneurysm, and 6 were postoperative cases of the abdominal aortic aneurysm. Nicardipine hydrochloride is easy to administer, has few side effects, and was found to be effective as antihypertensive therapy before and after surgery. The use of nicardipine hydrochloride has therefore been adopted by this unit as part of the treatment protocol for these patients.

The goal of organ preservation is maintenance of physiologic functions during extended extracorporeal storage.This study was designed to evaluate the efficacy of using low-potassium (4 mmol/L) dextran (1%) solution on lung function after 30 hours hypothermic (10 degrees C) storage and to compare this with lung function after no storage. With low-potassium dextran solution rabbit lungs were flushed (10 degrees C, 40 ml/kg, 60 cm H2O), excised, inflated (with room air), and either not stored (control; no preservation; n = 9) or stored in low-potassium dextran solution (10 degrees C) 30 hours (experimental group; n = 9).During the flush the infusion pressure and pulmonary vascular resistance for the two groups did not differ (17.56 +/- 1.3 versus 16.74 +/- 1.5 mm Hg/ml/sec). After either no preservation or after 30 hours of storage, the lungs were first reperfused with low-potassium dextran solution (37 degrees C) for 4 minutes and then with blood (37 degrees C) for 30 minutes at 100 ml/min. During the reperfusion period the mean pulmonary artery pressure and end-inspiratory airway pressure for the control and experimental groups did not differ. After reperfusion the wet and dry weights of the left lung were determined. The wet/dry ratio for the two groups did not differ (5.32 +/- 2.20 versus 4.70 +/- 2.70, respectively).These data suggest that cold flush, cold storage, and initial warm perfusion with low-potassium dextran solution crystalloid preserve lung function after 30 hours of storage.

A case of mediastinal cavernous hemangioma was reported. An asymptomatic 6-year-old girl was discovered to have a mass in the left anterior superior mediastinum on a routine chest x-ray film. Computed tomograms demonstrated a mediastinal mass with calcification. Under a median sternotomy, a 10 x 9 x 5 cm mass was resected after dissecting the connections to the pericardium. As the mass surrounded the left phrenic nerve, the nerve was resected with the tumor. The histopathology was cavernous hemangioma. The calcification was not found in the vessels as the phleboliths but was showed in the interstitial tissues.

Esophageal duplication cyst associated with pericardial defect in a 57-year-old man is reported. Differential diagnosis was very difficult in the preoperative examination. The tumor was a cyst and its wall was a perfect replica of normal esophagus e.g. esophageal duplication, and total left pericardial defect also was found at the operation. There was no malignant or inflammation findings in the excised specimens. The association of esophageal duplication cyst associated with pericardial defect is very rare.

We report new results on charge multiplicities fromπ+ Ne andπ- Ne interactions at 30 and 64 GeV/c. The average number of fast protons is extracted and found to be essentially independent of the number of identified slow protons.

We present a simple introduction to the basic physical ideas involved in the flux quantization number carried by systems such as magnetic monopoles and vortices. By using simple geometrical arguments, we see that the flux number is associated with a hidden symmetry in gauge theory that is topological in origin.

A PEPR vertex guidance system requiring no operator intervention has been operating at the University of Washington's Visual Techniques Laboratory since 1972. The measurement of 140 000 events consisting of 3, 4, 5, and 6-prong interactions of a 15 GeV/ c π − beam with deuterium was recently completed. The system employs global transformations that reduce circular tracks to a point in a two-dimensional angle-curvature space. Noise reduction techniques are used to improve position and angle accuracy and thereby the system resolution and efficiency. Monitoring criteria were developed to ensure continous peak performance over long production periods.

In an exposure of the Fermilab 15-foot neon-hydrogen bubble chamber to a quadrupole triplet neutrino beam, 49 ..mu../sup -/e/sup +/ and 14 ..mu../sup +/e/sup -/ events with e/sup + -/ momenta greater than 0.3 GeV/c have been observed, yielding ..mu..e rates per charged-current event of (0.73 +- 0.11)% and (1.1 +- 0.3)%, respectively. The ..mu../sup -/e/sup +/ rate shows no strong energy dependence in the range from 30 to 300 GeV. The 18 neutral strange particles observed in the 63 events contain 14 K/sup 0//sub S/, 2 ..lambda.., and 2 ..lambda../K/sup 0//sub S/ ambiguities, suggesting that the events are predominantly D-meson production and decay and that the ..lambda../sup +//sub c/..--> lambda..eX branching ratio is very small. The corrected numbers of neutral strange particles per ..mu../sup -/e/sup +/ and ..mu../sup +/e/sup -/ event are 1.2 +- 0.3 and 0.6/sup +0.6//sub -0.3/, respectively. Properties of the events, including strange-particle production, are compared to ..mu../sup - +/..mu../sup + -/ events in the same experiment and to a charm production and decay model, and good agreement is found, apart from a possible enhancement at approx.5--6 GeV/c/sup 2/ in the mass of the system recoiling against the ..mu../sup +/ in ..mu../sup +/e/sup -/ (and ..mu../supmore » +/..mu../sup -/) events. As reported previously, four events show short-lived-particle decays, and D-meson lifetime estimates are reevaluated using the final event sample. One ..mu../sup +/e/sup +/ and three ..mu../sup -/e/sup -/ events were observed. The ..mu../sup -/e/sup -/ events are consistent with background and lead to a ..mu../sup -/e/sup -//..mu../sup -/e/sup +/ ratio of less than 0.07 (90% confidence level) for e/sup + -/ momenta above 0.8 GeV/c. Five candidates for dilepton production by electron neutrinos and antineutrinos in the beam are consistent with approximately 1% rates. No good three-lepton candidates were found, and one, previously reported, four-lepton candidate was found.« less

Partial cross sections for double scattering are extracted from πd andpd interactions between 15 and 400 GeV. Various moments of the experimental distributions are compared with predictions of two theoretical models. Good agreement is found between the experimental results and the models.

Diffractive dissociation of neutrons and N ∗ production are studied in the reaction π − n → π − π − p at 15 GeV/ c . The reaction is dominated by a broad, low-mass diffractive enhancement in the pπ − mass. Evidence is presented for the production of at least one N ∗ resonance in the mass region 1.4–1.8 GeV. Comparison with ISR data suggest that this N ∗ resonance is produced by pomeron exchange. The N ∗ production occurs predominantly at t ′ > 0.1 GeV 2 which suggests a different coupling from the usual diffractive reactions. The non-resonant diffractive background is compared with a double-Regge model and the statistical dissociation model.

In a neutrino bubble-chamber experiment with a mean event energy of 90 GeV, clear evidence is observed for muon inner bremsstrahlung. The corrected rate, for gamma rays with E/sub ..gamma../>1 GeV and within 32 mrad of the muon direction, is 0.027 +- 0.005 per charged current event. Comparison with QED calculations is discussed.

Coherent rho/sup +/ production on neon nuclei has been observed in charged-current events in a neutrino bubble-chamber experiment. The incident neutrino energy was 10--320 GeV, with a median event energy of 80 GeV. The rate per charged-current event was (0.28 +- 0.10)%. Comparison was made to vector-meson-dominance predictions; agreement with the overall rate, but disagreement at high neutrino energies and at high Q/sup 2/, was found.

We report observation of a neutrino (antineutrino)-induced event with two electrons, one positron, one positively charged muon, a neutral K meson, and seven gammas in an experiment performed in the FNAL 15-ft. bubble chamber with a 47% atomic mixture of neon in hydrogen. Estimated experimental electron backgrounds are ∼10 −4 per track. At present we have no plausible interpretation of this event.

A basic primer for QCD is presented using a semiclassical approach to the colour Maxwell equations. The non-Abelian nature of colour symmetry and the violation of superposition by colour fields is compared with QED. A simple discussion of asymptotic freedom is also presented.

A broad threshold dπ+π− enhancement has been observed in π−d → dπ+π−π− at 15 GeV/c. It can be described by a model which assumes terms involving intermediate N12∗ production, plus a Deck type enhancement. A simple calculation based on π±p data is successful in reproducing the main features of the data.

In charged-current neutrino-neon events (mean energy 100 GeV), fast charged hadrons show an up-down asymmetry with respect to the lepton plane. The asymmetry may be associated with reinteractions in the neon nuclei. For z>0.3 hadrons the asymmetry is -0.054 +- 0.017; for those events showing evidence for reinteractions the asymmetry is -0.111 +- 0.028. For all hadrons the asymmetry is 0.0010 +- 0.0048.

In an experiment (E546) to study interactions of {l angle}{ital E}{r angle}=100 GeV and {l angle}{ital Q}{sup 2}{r angle}=17 GeV{sup 2} neutrinos in the Fermilab 15-foot bubble chamber, we have looked for a left-right asymmetry in the azimuthal angle {phi} of individual hadrons about the direction of the lepton momentum transfer ({ital q} vector). Significant asymmetry is found for forward positive hadrons; for {ital x}{sub {ital F}}{gt}0.10, we find {l angle}cos{phi}{r angle}={minus}0.029{plus minus}0.008, where {ital x}{sub {ital F}} is the Feynman {ital x} variable. Negative hadrons with {ital x}{sub {ital F}}{gt}0.10 show no asymmetry, {l angle}cos{phi}{r angle}=0.004{plus minus}0.011. A model which includes parton intrinsic transverse momentum {ital k}{sub {ital t}} reproduces the asymmetry of combined positive and negative hadrons with {ital x}{sub {ital F}}{gt}0.10, {l angle}cos{phi}{r angle}={minus}0.018{plus minus}0.0065, if {l angle}{ital k}{sub {ital t}}{sup 2}{r angle}=0.065{plus minus}0.024 GeV{sup 2}/c{sup 2}. But the model predicts almost equal asymmetries for positive and negative hadrons. The model also agrees poorly with the observed dependence on the kinematic variables {ital x} and {ital Q}{sup 2} if the {ital k}{sub {ital t}} distribution is assumed to be independent of kinematic variables.

Kinematic selection criteria are developed for separating tau-neutrino charged-current interactions from a large background of muon- and electron-neutrino interactions. The criteria are designed to detect the three-prong decay mode of the $\ensuremath{\tau}$ lepton and rely on the three-particle combination's transverse momentum being anticorrelated with the tr\'ansverse momentum of the other visible particles and being correlated with the missing transverse momentum. The criteria are applied to a sample of events from an exposure of the Fermilab 15-ft bubble chamber to the quadrupole triplet neutrino beam. The average event energies for this beam are 90 GeV for neutrino and 60 GeV for antineutrino events. The $14 \ensuremath{\tau}$ candidates selected agree with the calculated background of 14.3\ifmmode\pm\else\textpm\fi{}1.2. An upper limit on the probability of muon neutrinos oscillating into tau neutrinos of 0.053 is obtained.

The diffractive dissociation of pions into 3π and 5π final states has been studied using π−d interactions at 15 GeV/c. Peripherally produced low-mass enhancements are observed in both channels. the 3π enhancements consist predominantly of two-body final states, ϱπ, andfπ; evidence for agπ enhancement is inconclusive. The 5π channel shows no strong two-body structure. A multiperipheral Deck model and the statistical dissociation model are studied as possible mechanisms for these enhandements. The multiperipheral model describes the 3π channel well, whereas the less structured statistical model gives a better description of the 5π data.

We present the ..pi../sup -/d charged multiplicity distributions at 15 GeV/c and examine the probability that the products of a ..pi../sup -/n collision in a deuterium nucleus rescatter on the proton. Averaged over all topologies, this probability is 0.13 +- 0.02. The rescatter probability as a function of the number of charged particles produced in the ..pi../sup -/n interaction exhibits an increase at high multiplicity.

Results on inclusive particle production in π−n interactions at 21, 205 and 360 GeV/c are presented. The invariant cross sections in both neutron fragmentation and central regions are found to be equal within errors to the corresponding cross sections for π−p collisions and exhibit the same energy dependence. A strong energy dependence of the invariant cross section ratios of negative and positive pions is observed. There is also an indication of transverse momentum dependence of these ratios. The η− correlations in the neutron fragmentation region show little variation with energy and are in agreement with the predictions of the naive quark recombination scheme.

A pedagogical approach to gauge invariance is presented which is based on the analogy between gauge transformations and relativity. By using the concept of an internal space, purely geometrical arguments are used to teach the physical ideas behind gauge invariance. Many of the results are applicable to general gauge theories.

Diffractively produced five-pion final states are studied in the reaction π−d → 3π−2π+d at 15 GeV/c and compared with predictions of the statistical dissociation model and multiperipheral models.

Examination of a sample of 89 high-energy, neutrino-induced dilepton events produced in the Fermilab 15 ft bubble chamber has resulted in the direct observation of the production and visible semi-leptonic decay of short-lived particles. One charged decay, two neutral decays, and one decay candidate of undetermined charge are found. Assuming these events and the remaining dilepton signal result from D meson decays, we obtain τ D + = 2.5 −1.5 +3.5 × 10 −13 s and τ D 0 = 3.5 −1.7 +3.5 × 10 −13 s, using a maximum likelihood analysis.

Evidence for a bound ${\ensuremath{\Delta}}_{33}(1236)\ensuremath{-}{\ensuremath{\Delta}}_{33}(1236)$ component of the deuteron is sought by using ${\ensuremath{\pi}}^{+}$, ${\ensuremath{\pi}}^{\ensuremath{-}}$, and ${K}^{+}$ mesons as probes of nuclear structure. Events are observed which might contain $\ensuremath{\Delta}(1236)$ "spectators" in the breakup of a deuteron in a $\ensuremath{\Delta}\ensuremath{\Delta}$ state. However, other mechanisms may contribute to the signal, and we cannot unambiguously ascribe our events to a $\ensuremath{\Delta}\ensuremath{\Delta}$ contribution in the deuteron. With certain assumptions we obtain an upper limit of \ensuremath{\sim}0.7% for the $\ensuremath{\Delta}\ensuremath{\Delta}$ component of the deuteron.

Double-scattering effects are studied in π − d interactions at 360 GeV/ c . The partial cross sections σ N (π − d ), σ N (“π − p ”) and σ N (“π − n ”) are presented. The double-scattering probability per π d collision is found to be ƒ = 0.15 ± 0.02 . We have extracted the partial cross section X N of the double-scattering plus interference contributions, and find that X N obeys KNO scaling. The data are compared with various theoretical predictions.

The inclusive production of neutral particles are studied in π−d interactions at 205 GeV. Topological distributions for the inclusive reactions π−d → γ + d, π−d → Ks0+x, π−d → Γ + x and the cross section for π−d → Γ + x are presented and compared with π−p and pp interactions at 100 and 205 GeV. The effects of double scattering are studied and π−n inclusive distributions are obtained and compared to results from π−p interactions (in hydrogen) at 205 GeV.

We present a simple introduction to the basic physical ideas involved in the breaking of local gauge symmetry. By utilizing the geometrical approach to gauge invariance, we see that symmetry breaking corresponds to a phase adjustment in the interaction between a gauge field and a special class of ’’self‐coherent’’ systems. As examples, we discuss superconductivity and spontaneous symmetry breaking in elementary particle physics.

The inclusive distributions of hadrons produced in ν μ ( ν μ ) Ne interactions are found to be similar to inclusive distributions in π±Ne interactions.

Gauge theory is a classic example of a good idea proposed before its time. We present a brief historical review of gauge theory to see why it required over 50 years for gauge invariance to be rediscovered as the basic principle governing the fundamental forces of Nature.

We have measured the inclusive cross section for the reaction π − n→pX −− at 21, 205 and 360 GeV/ c in the kinematic region | t np | c ) 2 . The differential cross sections can be described qualitatively by the reggeized one-pion-exchange amplitude at all momenta studied; however, there is evidence for the contribution of other amplitudes. The extracted π − π − total cross section for 4⪅ s ππ ⪅340 GeV 2 is of the order of 10–12 mb. The average number of charged particles and dispersion of the charged particle multiplicity distributions for various s ππ intervals are compatible with results observed in hadron-proton interactions.