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An atmosphere-sea ice-ocean interaction study was conducted at the Saroma-ko Lagoon, Hokkaido, Japan from 27 February to 9 March 2021. Air-sea ice CO2 flux measurements were conducted by eddy covariance and chamber methods together with meteorological observations. Sea ice cores were collected to understand the interaction between the atmosphere and under-ice water with respect to fluxes of heat and biogeochemical components. Physical and biogeochemical parameters such as temperature, salinity, ice structure. environmental DNA, and concentrations of gases, nutrients, and trace metals were measured. Under-ice water properties were monitored to quantify heat budgets and interactions with sea ice biogeochemical properties. Incubation experiments with ice algae were conducted. Equipment such as air sea ice CO2/CH4 flux chambers, an eddy covariance system, a trace metal analyzer, and a pump and sampler for environmental DNA were tested and compared to prepare for future Arctic and Antarctic expeditions. In addition. movies and pictures were taken under the auspices of the educational program of Hokkaido University (LASBOS) to enhance educational programs in ocean science. The field campaign activities provided useful information for inter-comparison research and future studies of sea ice in polar oceans.

Titania layer was fabricated on the titanium substrates with chemical treatment with 20ml or 40ml of hydrogen peroxide solution and subsequent heat treatment at 400°C, coded as CHT20 and CHT40, respectively. CHT20 spontaneously deposited apatite on the surface in a simulated body fluid (SBF), while CHT40 did not. TF-XRD patterns showed that the diffraction intensity of anatase of CHT20 was higher than that of CHT40. It was suggested that the thicker titania layer indicated in vitro apatite forming ability. The cell proliferation of CHT20 and CHT40 were lower than NT and HT. Since the surface of titania layers became hydrophobic after autoclaving, we can suppose that the cell proliferation on CHT20 and CHT40 were lower than NT and HT due to their surface hydrophobicity.

Fine particles of calcium oxide doped cerium dioxide, 2–4 nm in diameter, were prepared by the chemical reaction of CeCl3-CaCl2 mixed aqueous solution and NaOH aqueous solution at pH 6–12 and 40°C followed by the oxidation with hydrogen peroxide. Doping of CaO with CeO2 resulted in decreasing the particle size and consequently, increasing UV shielding efficiency and transparency to visible light. The particle shape of ceria changed significantly depending on the reaction condition, i.e., rod-like particles and spherical particles were formed by the H2O2 oxidation of cerium trihydroxide pH above 8 and below 7, respectively.

Background. Auxiliary liver transplantation has several advantages over standard orthotopic liver transplantation. However, functional competition has been reported even in auxiliary partial orthotopic liver transplantation (APOLT). We evaluated herein the interaction in APOLT between the native liver and the graft in terms of portal blood flow and regeneration. The need for diversion of the portal blood flow to the graft was also assessed. Methods. A total of 15 patients received APOLT from living donors. Portal blood flow to the native liver was preserved in 6 patients, and the portal vein to the native liver was preemptively transected at the time of transplantation in 9 patients. Results. Of the patients with preservation of the portal blood flow to the native liver, two showed inadequate graft portal blood flow just after operation, and in the other three patients the graft portal blood flow decreased or the graft atrophied after deterioration of the graft function. In the patients with preemptive transection of the portal vein to the native liver, optimal graft portal blood flow was obtained, and the native liver, supplied only by arterial inflow, supported a small-for-size graft until the graft regenerated. The damage to the native liver was minimal. Conclusions. Functional competition may occur in APOLT with preservation of the portal blood flow to the native liver, whereas preemptive transection of the native liver portal vein is a safe procedure and effectively prevents the portal steal phenomenon.

A Nb/AlO/sub x//Nb Josephson process has been developed to fabricate DC superconducting quantum interference devices (SQUIDs) for biomagnetic measurements on 4-in silicon wafers. The purpose of the process is to fabricate high-quality junctions and to keep the quality uniform over a silicon wafer. All the films were deposited using magnetron sputtering. The components of the SQUID, except the junctions, were formed by taper etching to improve the step coverage. The uniformity of the SQUID characteristics (critical current, modulation depth, and mutual inductance between SQUID and modulation coil) was measured, and an excellent value of less than +or-5% was obtained. Three different configurations of SQUIDs, single washer (SW), double washer series (DWS), double washer parallel (DWP) have been fabricated with the same characteristics. The SW (single washer) had a white noise level of 6.3*10/sup -6/ Phi /sub 0// square root Hz, lower than those of DWS and DWP. 1/f crossover frequencies were below 1 Hz. >

Titania layer was fabricated on the titanium substrates with chemical treatment with 20ml or 40ml of hydrogen peroxide solution and subsequent heat treatment at 400°C, coded as CHT20 and CHT40, respectively. CHT20 spontaneously deposited apatite on the surface in a simulated body fluid (SBF), while CHT40 did not. TF-XRD patterns showed that the diffraction intensity of anatase of CHT20 was higher than that of CHT40. It was suggested that the thicker titania layer indicated in vitro apatite forming ability. The cell proliferation of CHT20 and CHT40 were lower than NT and HT. Since the surface of titania layers became hydrophobic after autoclaving, we can suppose that the cell proliferation on CHT20 and CHT40 were lower than NT and HT due to their surface hydrophobicity.

Flow through the vertical axis cross-flow wind turbine was analyzed using computational fluid dynamics (CFD) to clarify current aerodynamic issues and to propose an improved design configuration for achieving better performance. The computed torque coefficients and power coefficients of a reference cross-flow wind turbine runner were compared with the experimental results. Flow around each blade of the turbine runner was then investigated based on the computed flow results. As a countermeasure to the issues found, a new wind turbine design was devised which has two guide vanes point-symmetrically arranged outside the turbine runner. It was experimentally shown that this improved design with the guide vanes increased turbine efficiency. However, performance predictions by CFD lack sufficient accuracy in the case of the turbine runner with the guide vanes, where complexity and unsteadiness prevail over the entire flow fields.Copyright © 2006 by ASME

In many cases of small scale software development, downstream activities are actually carried out before upstream activities have completely finished in order to reduce the development time and meet the deadline. However, overlapping activities also increase the total work effort because it demands more communications between activities. It is very important to be able to estimate the tradeoff between development time and total work effort since constraints may be placed on them. The paper proposes a simulation model to describe the overlapping development processes and the effects between overlapped activities. Based on this model, a software process simulator was developed. This simulator is applicable for supporting project planning (scheduling and staffing) with constraints on cycle time and total work effort.

Two practical protective tools for occupational exposure for neurointerventional radiologists are presented. The first purpose of this study was to investigate the effectiveness of double focus spectacles for the aged with a highly refracted glass lens (special spectacles for the aged) for radiation protection of the crystalline lens of the eye in comparison with other spectacles on the market, based on the measurement of film density which was obtained by exposure of X-ray through those spectacles. As a result of the film densitometry mentioned above, the effectiveness of special spectacles for the aged in radiation protection was nearly equal to the effectiveness of a goggle type shield which is made with a 0.07 mm lead-equivalent plastic lens. The second purpose of this study was to investigate the effectiveness of the protective barrier, which we remodeled for cerebral angiography or neuroendovascular therapy, for radiation exposure, based on the measurement in a simulated study with a head phantom, and on the measurement of radiation exposure in operaters during procedures of clinical cases. In the experimental study radiation exposure in supposed position of the crystalline lens was reduced to about one third and radiation exposure in supposed position of the gonadal glands was reduced to about one seventh, compared to radiation exposure without employing the barrier. The radiation exposure was monitored at the left breast of three radiologists, in 215 cases of cerebral angiography. Employing the barrier in cerebral angiography, average equivalent dose at the left breast measured 1.49mu Sv during 10 min of fluoroscopy. In three kinds of neuroendovascular therapy in 40 cases, radiation exposure in an operator was monitored in the same fashion and the dose was recorded less than the result reported in previous papers in which any protective barrier have not been employed in the procedure (1,2). As a result, the two above mentioned protective tools are considered practical in clinical usage and very effective to reduce radiation exposure in an operator of interventional neuroradiolgy which may sometimes require many hours to complete the therapy under extended fluoroscopic time. 1) The first topic of this report is double focus spectacles for the aged with a highly refracted glass lens (special spectacles for the aged).

Functional competition has been shown to lead to a detrimental outcome in auxiliary liver transplantation. We evaluated the interaction in auxiliary partial orthotopic liver transplantation between the native liver and the graft in terms of portal flow and regeneration. The need for diversion of the portal flow to the graft was also assessed. Reduced-size liver grafts were transplanted orthotopically after partial hepatectomy in beagles. There were two groups: the preserved group, where portal inflow to the native liver was preserved, and the ligated group, where it was interrupted. Portal flow was measured serially and liver regeneration was evaluated on postoperative day 5. Functional competition was not observed in the preserved group. On the other hand, ligation of the native liver portal vein had no obviously detrimental effects on the remnant native liver. This leads to the conclusion that the portal vein to the native liver can be safely ligated to prevent functional competition.

Auxiliary liver transplantation has several advantages over standard orthotopic liver transplantation. However, functional competition has been reported even in auxiliary partial orthotopic liver transplantation (APOLT). We evaluated herein the interaction in APOLT between the native liver and the graft in terms of portal blood flow and regeneration. The need for diversion of the portal blood flow to the graft was also assessed.A total of 15 patients received APOLT from living donors. Portal blood flow to the native liver was preserved in 6 patients, and the portal vein to the native liver was preemptively transected at the time of transplantation in 9 patients.Of the patients with preservation of the portal blood flow to the native liver, two showed inadequate graft portal blood flow just after operation, and in the other three patients the graft portal blood flow decreased or the graft atrophied after deterioration of the graft function. In the patients with preemptive transection of the portal vein to the native liver, optimal graft portal blood flow was obtained, and the native liver, supplied only by arterial inflow, supported a small-for-size graft until the graft regenerated. The damage to the native liver was minimal.Functional competition may occur in APOLT with preservation of the portal blood flow to the native liver, whereas preemptive transection of the native liver portal vein is a safe procedure and effectively prevents the portal steal phenomenon.

Hepatic artery thrombosis (HAT) after orthotopic liver transplantation remains a significant cause of graft loss in pediatric patients. We previously reported that the microsurgical techniques for arterial anastomosis can reduce the incidence of HAT in living related liver transplantation (LRLT). The purpose of this study is to analyze the risk factors for HAT after LRLT. A total of 245 patients received 250 liver transplants.Eight arteries in eight patients, reconstructed with the use of loupe magnification (HAT; 1/8, 12.5%), were excluded from this study. We observed HAT in 4 patients of the 242 transplants (1.7%, HAT group). Seventeen factors were compared between the HAT and the control group (those without HAT).HAT occurred in 3 of 33 grafts (9%) from ABO-incompatible donors, whereas it occurred in 1 of 209 grafts (0.5%) from identical or compatible donors (P=0.008). The corrected volume of fresh-frozen plasma intraoperatively transfused in the HAT group (46.9+/-30.3 ml/kg) was significantly (P=0.015) different from that in the control group (10.2+/-1.9 ml/mg). In all four patients with HAT, emergent revisions of the anastomosis were performed. Two patients with ABO-incompatible grafts died of hepatic failure and sepsis.Although microsurgical techniques can minimize the surgical risk factors for HAT, overtransfusion of fresh-frozen plasma in high-risk patients (ABO incompatible) may be a critical factor in the development of HAT in LRLT.

Auxiliary partial orthotopic liver transplantation (APOLT) has recently been performed in patients with noncirrhotic metabolic liver diseases. However, long-term outcomes for the preserved native liver and the transplanted liver graft have not been clearly established yet.The recipient was a 36-month-old girl with ornithine transcarbamylase deficiency. She underwent APOLT, using her father's left lateral segment.Liver function was normalized soon after APOLT and the patient was able to ingest a normal diet without medication. Coexistence of the well-functioning native liver and graft was demonstrated in a computed tomography scan, Doppler ultrasonography, scintigraphy, and histological examination, during a relatively long-term follow-up period.APOLT seems to be most useful for the treatment of noncirrhotic metabolic liver diseases.

OBJECTIVE: To investigate the value of a giant negative T wave (> or = 1.0 mV) in precordial leads of 12-lead electrocardiograms in the acute phase of Q wave myocardial infarction as a predictor of myocardial salvage. METHODS: Coronary angiographic and electrocardiographic findings, left ventricular ejection fraction in the chronic stage, and levels of cardiac enzymes were compared in patients with myocardial infarction with (group GNT, n = 31) and without (group N, n = 20) a giant negative T wave. GNT patients were divided into two subgroups according to the presence (GNT:R[+], n = 10) or absence (GNT: R[-], n = 21) of R wave recovery with an amplitude > or = 0.1 mV in at least one lead that had shown Q waves. RESULTS: The maximum level of creatine kinase and the total creatine kinase were lower in group GNT compared with group N (P < 0.05). The left ventricular ejection fraction was higher in group GNT than in group N (P < 0.05). The maximum creatine kinase and total creatine kinase were lower in GNT:R(+) than in GNT:R(-) (P < 0.01). The left ventricular ejection fraction was higher in GNT:R(+) than in GNT:R(-) (P < 0.01). The frequency of R wave recovery was significantly higher when giant negative T waves appeared within 100 h of myocardial infarction or when the maximum potential was > or = 1.4 mV. The appearance of a giant negative T wave > or = 1.4 mV had a sensitivity of 90%, a specificity of 71.4%, a diagnostic accuracy of 77.4%, a positive predictive value of 60%, and a negative predictive value of 93.8% for prediction of R wave recovery. CONCLUSIONS: The appearance of a giant negative T wave, especially within 100 h of the onset of myocardial infarction, with a maximum potential of > or = 1.4 mV, may predict a reappearance of the R wave and a better left ventricular function in patients in the chronic stage of anterior myocardial infarction.

Living related liver transplantation (LRLT) was performed in seven children with hypoxemia related to intrapulmonary shunting. Based on the degree of the shunt ratio calculated by technetium 99m macroaggregated albumin (MAA) scintigraphy, the seven patients were classified in the moderate (shunt ratio under 40%, n = 4) or severe group (shunt ratio over 40%, n = 3). While PaO2 was maintained over 60 mmHg in the moderate group, that in the severe group continued at a low level of under 40 mmHg in the early postoperative period. However, 48 h after surgery the arterial ketone body ratio recovered to a safe level of 1.0 in both groups. Values of aspartate aminotransferase and serum total bilirubin decreased at a constant rate in both groups. Six patients survived, but one died of portal vein thrombosis on the 53rd postoperative day. Five of six surviving patients recovered from hypoxemia. We concluded that the transplanted liver can tolerate the stress of severe hypoxemia after LRLT.

Living related liver transplantation (LRLT) was performed in seven children with hypoxemia related to intrapulmonary shunting. Based on the degree of the shunt ratio calculated by technetium 99m macroaggregated albumin (MAA) scintigraphy, the seven patients were classified in the moderate (shunt ratio under 40%, n = 4) or severe group (shunt ratio over 40%, n = 3). While PaO2 was maintained over 60 mmHg in the moderate group, that in the severe group continued at a low level of under 40 mmHg in the early postoperative period. However, 48 h after surgery the arterial ketone body ratio recovered to a safe level of 1.0 in both groups. Values of aspartate aminotransferase and serum total bilirubin decreased at a constant rate in both groups. Six patients survived, but one died of portal vein thrombosis on the 53rd postoperative day. Five of six surviving patients recovered from hypoxemia. We concluded that the transplanted liver can tolerate the stress of severe hypoxemia after LRLT.

In homogeneous enzyme immunoassay without requirement of separation of free and bound label, the concentration of substances in samples can be detected by measurement of enzyme activity in the mixtures of samples (antigen) and reagents (labeled antigens antibodies, and enzyme substrates). The methods described herein offer the virtues of simplicity and rapidity by use of general-purpose automated clinical analyzer. The concentrations of some drugs, hormones, antibiotics, and very small amount of certain proteins are now detected by the routine examination in these techniques employing commercial diagnostic kits offered by several companies. In this manuscript, we attempted to give an overview of the principle of various methods by use of commercial diagnostic kit applied in routine clinical examinations.

Bottazzo et al. first reported an assay method of antibodies to human pituitary endocrine cells, using an indirect immunofluorescent technique in 1975. In 1986 Sugiura et al. established a sensitive assay method for pituitary cell antibodies by biotin/avidin detection technique using rat pituitary. They also developed a sensitive assay for antibodies to anterior pituitary cell membrane by immunofluorescence methods using AtT-20 cells and GH3 cells. Recently Crock et al. reported a new approach to the detection of pituitary antibodies by immunoblotting. We focused on assay methods reported previously, including our results of pituitary antibodies in patients with autoimmune thyroid disease. The existence of autoimmune disorders of the pituitary is now accepted on both experimental and clinical grounds.

The identification of local activation events in bipolar cardiac electrograms, the first step of isochronal map construction, is a time-consuming and difficult process. Owing to the variability among bipolar activation complexes and the lack of practical knowledge concerning the relationship of the bipolar waveform to action potential characteristics, a set of empirical rules to guide the assignment of local activation times have been adopted. A computer program, called AP, has been designed, which implements these rules in the form of a syntactic analyser. Canine epicardial recordings were used to evaluate AP by comparing local activation times, assigned by AP, with times assigned independently by three investigators. The Hermes-Cox model for detector evaluation and a bootstrap statistical method were used in conjunction with ROC analysis to evaluate the ability of AP to detect events. Analysis of discrepancies among investigator-assigned times showed that the reliabilities of AP event detection and AP-assigned times were comparable to those of the investigators. The methods used in system design and evaluation are applicable to a broad range of problems in the detection and localisation of waveform components.

We previously reported that Tbx6, a T-box transcription factor expressed in nascent nonaxial mesoderm, is required for the differentiation of ventral body wall muscle and for segment formation and somitic muscle differentiation in Xenopus laevis . Here, we show that Tbx6 is also involved, at later stages, in cartilage differentiation from the cranial neural crest and head muscle development. In Tbx6 knockdown embryos, the cranial neural crest was shown to be correctly induced at the border of the neural plate and migrated in a slightly delayed manner, but finally reached positions in the pharyngeal arches nearly identical to those in the normal embryos as revealed by in situ hybridization and the neural crest-transplantation experiments. However, the neural crest cells failed to maintain Sox9 expression. In order to clarify the reasons why Tbx6 knockdown affects the development of head and pharyngeal muscles and cartilages, we noticed on Tbx1, another T-box gene expressed in more anterior paraxial structures, and a gene responsible for human DiGeorge syndrome, as a candidate to mediate Tbx6 function. Tbx6 knockdown reduced the expression of Tbx1. Next, Tbx1 knockdown caused phenotypes milder but similar to those of Tbx6 morphants, including reduced formation of head muscles and cartilages, and attenuated Sox9 expression. Furthermore, the phenotypes caused by Tbx6 knockdown were partially rescued by Tbx1 plasmid injection. Tbx6 expression in Tbx1 knockdown embryos was not reduced at all, but rather expanded in anterior direction, suggesting that Tbx6 is epistatic to Tbx1. This expansion of Tbx6 expression in Tbx1 morphants, when considered together with the fact that there was a gap between the anterior Tbx1-expressing and posterior Tbx6-expressing areas in normal neurula to early tailbud embryos, implys the presence of interaction between the anterior and posterior paraxial mesodermal tissues. These results suggest that Tbx6 is involved in the cranial cartilage and head muscle development by regulating anterior paraxial genes such as Tbx1 and Sox9.

BACKGROUND Potential gradient field determination may be a helpful means of describing the effects of defibrillation shocks; however, potential gradient field requirements for defibrillation with different electrode configurations have not been established. METHODS AND RESULTS To evaluate the field requirements for defibrillation, potential fields during defibrillation shocks and the following ventricular activations were recorded with 74 epicardial electrodes in 12 open-chest dogs with the use of a computerized mapping system. Shock electrodes (2.64 cm2) were attached to the lateral right atrium (R), lateral left ventricular base (L), and left ventricular apex (V). Four electrode configurations were tested: single shocks of 14-msec duration given to two single anode-single cathode configurations, R:V and L:V, and to one dual anode-single cathode configuration, (R+L):V; and sequential 7-msec shocks separated by 1 msec given to R:V and L:V (R:V----L:V). Defibrillation threshold (DFT) current was significantly lower for R:V----L:V than for the other configurations and markedly higher for L:V. Despite these differences, the minimum potential gradients measured at DFT were not significantly different (approximately 6-7 V/cm for each electrode configuration). Potential gradient fields generated by the electrode configurations were markedly uneven, with a 15-27-fold change from lowest to highest gradient, with the greatest decrease in gradient occurring near the shock electrodes. Although gradient fields varied with the electrode configuration, all configurations produced weak fields along the right ventricular base. Early sites of epicardial activation after all unsuccessful shocks occurred in areas in which the field was weak; 87% occurred at sites with gradients less than 15 V/cm. Ventricular tachycardia originating in high gradient areas near shock electrodes followed 11 of 67 successful shocks. CONCLUSIONS These data suggest that 1) defibrillation fields created by small epicardial electrodes are very uneven; 2) achievement of a certain minimum potential gradient over both ventricles is necessary for ventricular defibrillation; 3) the difference in shock strengths required to achieve this minimum gradient over both ventricles may explain the differences in DFTs for various electrode configurations; and 4) high gradient areas in the uneven fields can induce ectopic activation after successful shocks.

During internal defibrillation, potential gradients greater than 100 V/cm occur near defibrillation electrodes. Such strong fields may cause deleterious effects, including arrhythmias. This study determined 1) the effects of such strong fields on the propagation of activation and 2) whether these effects were different for monophasic and biphasic shocks. Voltages and potential gradients during the shock, as well as activation sequences before and after the shock, were mapped from 117 epicardial electrodes placed over a 3 x 3-cm area on the right ventricle in six dogs. Pacing at a cycle length of 350 msec was given from a long narrow electrode on the right side of the mapped area to generate parallel activation isochrones. A monophasic shock, 10 msec in duration, or a biphasic shock with both phases 5 msec in duration was delivered 300 msec after the last paced stimulus via a mesh electrode on the left side of the mapped area as the cathode, with the anode on the right atrium. Shocks of 70-850 V were given, and the potential gradient and current density at each recording electrode were calculated from the measured potentials and fiber orientation by using a finite element method. Pacing was resumed 200 msec after the shock, and activation sequences were mapped for up to 5 minutes. Potential gradients ranged from 1 to 189 V/cm with high fields on the left side and low fields on the right side of the mapped area. Where the potential gradient was weak, the first activation sequence after the shock was similar to that before the shock, but activation blocked without conducting into areas where the gradient was greater than 64 +/- 4 (mean +/- SD) V/cm for monophasic and greater than 71 +/- 6 V/cm for biphasic shocks. These values are significantly different (p less than 0.003). The higher the potential gradient, the longer was the duration of block before conduction returned. Block duration, however, was generally shorter for biphasic than for monophasic waveforms of the same field strength. In conclusion, conduction block can follow either waveform, but biphasic waveforms cause less block than monophasic waveforms. This effect may partially explain the increased defibrillation efficacy of biphasic shocks.

A series of experiments on the role of lizards as overwintering hosts of Japanese encephalitis virus (JEV) was carried out. Two species of lizards, T. tachydromoides and E. latiscutatus, 2 species of mosquitoes, Cx. p. fatigans and Cx. p. pallens, and 2 strains of JEV, JaGAr#01 and JaGAr 19461, were used in this study. Firstly transmission of JEV from infected mosquitoes to uninfected lizards and from infected lizards to normal mice by the bite of mosquitoes was demonstrated successfully. Cx. pipiens group mosquitoes were found to feed readily on lizards as compared to Cx. tritaeniorhynchus, the primary vector of JEV in Japan. Secondly simulated hibernation of JEV in lizards was carried out under indoor and outdoor conditions. In the outdoor hibernation, lizards were injected with JEV on October 14, 1968, entered in hibernation on October 19 and were recovered from hibernation on April 10, 1969. Viremias were demonstrated in the lizards for a few weeks in late April. Thirdly JEV isolation and HI antibody detection were attempted from blood samples of field-caught reptiles, 7 species of snakes and 3 species of lizards and among amphibians, 2 species of frogs. HI antibody against JEV was found at a rate of 14.3% from E. latiscutatus and 4.0% from T. tachydromoides, though JEV was not isolated from all the blood samples of these cold-blooded animals. The roles of lizards as overwintering hosts of JEV were discussed.

The importance of detecting the high fidelity electrical activity of the heart was cited in respect to making diagnosis and providing optimal treatment. Standard 12 lead electrocardiograms (ECG) and vectorcardiograms (VCG) are used in daily practice with well-documented theoretical and experimental bases. However, this system is somewhat inadequate because of its simplicity both in records and basic assumptions. The development of a better lead system is thus mandatory for a high diagnostic sensitivity and specificity and for both qualitative and quantitative assessments of collected data. In recent years, great progress has been promised in "body surface mapping methods" by the medical application of computer technology, providing abundant information including four-dimensional displays; two-dimensional surface spreads of electricity as well as the magnitudes and time references. This method appears to be a powerful diagnostic tool, despite problems inherent in ECG and some unfavorable aspects yet to be settled. The present status, prospects and limitations of this new, powerful strategy are discussed.

Experimental infection of four species of snakes, Rhabdophis tigrinus tigrinus, Elaphe quadrivirgata, Elaphe climacophora and Agkistrodon halys, and five species of lizards, Takydromus tachydromoides, Eumeces latiscutatus, Eumeces barbouri, Eumeces marginatus oshimensis and Gekko japonicus, with Japanese encephalitis virus (JEV) was carried out. Evidence of JEV multiplication in snakes was not obtained at least under the conditions used in the present study. All lizards except G. japonicus were infected with JEV by ip injection of virus suspension. The minimum infectious dose for a lizard was around 10(3) MLD50/0.05 ml, and this dose was considered to be proportional to the virus dose which is injected into a host by a vector mosquito at a single bite. Temperature dependence of JE virus growth in the lizards was demonstrated. JEV multiplied slower at 20 degrees C than at 26 degrees C, though the peak titers of viremia were equivalent in both groups of lizards kept at 20 degrees C and 26 degrees C. E. latiscutatus developed viremia with ip injection of a partially attenuated strain, Nakayama NIH which could not infect adult mice by peripheral inoculation. T. tachydromoides and E. latiscutatus were also infected by oral feeding of JEV infected mosquitoes. E. latiscutatus was infected by oral feeding of only one infected mosquito.

This study related the eigenvectors derived from the QRS complex in body surface isopotential maps of normal subjects to regional myocardial excitation, with special emphasis on the right ventricle. The subjects consisted of 120 normal healthy adults and eight patients with primary pulmonary hypertension and right ventricular hypertrophy (PPH). According to the Karhunen-Loève theory, eigenvectors were derived from the normal group and the eigenvector coefficient of each subject was obtained against time for the first three components. The cumulative proportion of the first three eigenvectors was 90.3% in normals and 80.2% in PPH. The first eigenvector had a peak of eigenvector coefficients early in the QRS and had a bottom late in the QRS. The peak of the second was in the middle of the QRS. The coefficients of the third eigenvector were low compared to the former two eigenvectors, and had no characteristic time pattern. PPH had a similar time pattern of coefficients in the first eigenvector, reduced coefficients in the second, and a definite peak in the mid-QRS in the third. The average eigenvector coefficient of the third eigenvector in PPH was significantly higher than those in normal subjects (p less than 0.01). We conclude that the third eignevector derived from normal subjects strongly reflects right ventricular excitation.

Nine patients of sick sinus syndrome with atrial programmable pacemaker (3 males and 6 females, aged from 53 to 72 years) were studied to assess the effect of heart rate on the body surface potential distribution. Body surface maps (87 lead points) and M-mode echocardiograms were recorded at 20-beat increments of heart rate from 60 to 140 beats/min during atrial pacing. The potential changes of R and S voltages were evaluated quantitatively and were correlated with the changes of echocardiographically measured left ventricular dimension. As the heart rate increased, left ventricular dimension in end-diastole (LVDd) decreased gradually (Table 1), and a significant decrease was observed when the heart rate increased from 80 to 100 beats/min and from 100 to 120 beats/min, respectively, (p less than 0.05). With a decrease in LVDd, the distance between the left ventricular posterior wall and the anterior chest wall decreased and the left ventricular wall increased in its thickness. These changes, however, were not statistically significant. With an increase in the heart rate, R voltages decreased gradually in the left lateral chest and the sum of R voltages (sigma R) of six lead points in the left lateral chest including leads V5-6 decreased significantly when the heart rate increased from 60 to 100 beats/min and from 80 to 120 beats/min, respectively (p less than 0.02) (Table 2). On the other hand, R voltages remained unchanged in the left anterior chest during atrial pacing, then the sum of R voltages of six lead points in the left anterior chest including leads V2-4 and the sum of R voltages of 87 lead points did not show any significant changes (Table 2). An increase in the absolute value of S voltages was observed in the left anterior chest and the sum of S voltages of six lead points in the left anterior chest including leads V2-4 increased when the heart rate increased from 60 to 100 beats/min and from 80 to 120 beats/min, respectively (p less than 0.1) (Table 3) A decrease of R voltages in the left lateral chest was consistent with the reduction in LVDd (p less than 0.005). It is concluded that the changes in body surface QRS amplitudes during atrial pacing are related to those in the left ventricular dimension and that R voltages in the left lateral chest are fairly sensitive to see the changes in LVDd in cases with no abnormal wall motion of the left ventricle.(ABSTRACT TRUNCATED AT 400 WORDS)

Body surface mapping (map) was used to evaluate various cardiac diseases quantitatively. For 30 cases with old anterior myocardial infarction (AMI), map parameters were compared with infarct size assessed by left ventriculography and 201Tl myocardial scintigraphy (LV% asynergy and 201Tl% defect, respectively). Parameters used in the present study were nSubtraction 40 (sigma Subtr. 40), which were obtained by the summation of voltages less than the lower limit of normal range (mean--2SD) at 40 msec from the QRS onset and nSubtraction 10-60 (sigma Subtr. 10-60), which was obtained by the integral of voltages below the normal range, calculated each 10 msec to 60 msec, as well as the number of lead points with Q waves of 30, 40 msec duration (nQ30, nQ40), and the summation of R voltages over the entire body surface (sigma R). In 19 cases with aortic regurgitation (AR), R and S voltages in each lead were compared with left ventricular diastolic dimension (LVDd) obtained by echocardiography. In 43 healthy persons and two patients with RV pacing, the ventricular activation time was measured in each lead (VAT map). In AMI, nSubtr. 40 correlated best with LV% asynergy (r = 0.70, p less than 0.001). EF and 201Tl% defect were related to nSubtr. 10-60 (r = 0.83, p less than 0.001 and r = 0.85, p less than 0.001, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

This study was performed to evaluate the usefulness of the body surface isochrone map (VAT map) for identifying the ventricular activation sequence, and it was correlated with the isopotential map. Subjects consisted of 42 normal healthy adults, 18 patients with artificial ventricular pacemakers, and 100 patients with ventricular premature beats (VPB). The sites of pacemaker implantations were the right ventricular endocardial apex (nine cases), right ventricular epicardial apex (five cases), right ventricular inflow tract (one case), left ventricular epicardial apex (one case), and posterior base of the left ventricle via the coronary sinus (two cases). An isopotential map was recorded by the mapper HPM-6500 (Chunichi-Denshi Co.) on the basis of an 87 unipolar lead ECG, and a VAT isochrone map was drawn by a minicomputer. The normal VAT map was classified by type according to alignment of isochrone lines, and their frequency was 57.1% for type A, 16.7% for type B, and 26.2% for type C. In the VAT map of ventricular pacing, the body surface area of initial isochrone lines represented well the sites of pacemaker stimuli. In the VAT map of VPB, the sites of origin of VPB agreed well with those as determined by the previous study using an isopotential map. The density of the isochrone lines suggested the mode of conduction via the specialized conduction system or ventricular muscle. The VAT map is a very useful diagnostic method to predict the ventricular activation sequence more directly in a single sheet of the map.