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Since 1978 we have conducted extensive gravity surveys in Central Honshu, Japan, to establish 5,345 new gravity stations. The results are synthesized into a Bouguer anomaly map with the data from other sources. The map shows a distinctive belt of gravity gradient on the Pacific side of Central Honshu. This belt is about 300 km long and 30-50 km wide, across which Bouguer anomaly changes by about 30-50 mGals. Broad Bouguer high prevailing further oceanward of Central Honshu is sharply bounded by this anomaly belt. There seems to be no apparent correlation between this anomaly belt and the surface geology.

We carried out gravity surveys along four routes across the Peruvian Andes, one in northern Peru, one in central Peru, and two in southern Peru. Two of the routes extend from the coast to the flat lands of the Amazon Basin across the high Andes, while the other two routes extend only from the coast to the central high plateau or the Altiplano. One route through Nazca contains 250 data points over a length of 800 km and thus offers one of the best gravity profiles across the Andes. This profile shows quite asymmetric gravity anomalies associated with the Western Cordillera and the Eastern Cordillera, in marked contrast with the symmetric pattern of topographic profile. Using these profiles, we constructed crustal models varying layer thicknesses rather than layer densities. The crustal thickness has a maximum beneath the Western Cordillera, although the maximum thickness varies from 45 km in northern Peru to 55 km in central Peru and 65 km in southern Peru in contrast to the assumed thickness of 35 km beneath the stable Brazilian shield. Possible effects of lateral variations of crustal and mantle densities tend to reduce the above estimates of maximum thickness. The very shallow Moho beneath the Peruvian coast steeply deepens eastward in correspondence to the steep western slope of the Andes. The crust is thicker in the Western Cordillera than in the Eastern Cordillera. The Moho beneath the Eastern Cordillera tends to be relatively flat and shallows abruptly eastward across the sub-Andes. The Wadati-Benioff zone lies, in general, well below the model South American continental crust, leaving a mantle wedge in between. A notable exception is the Nazca profile, where the base of the model South American continental crust is in direct contact with the top of the Wadati-Benioff zone. This provides a direct evidence for uplifting of the buoyant slab with an aseismic ridge (the Nazca ridge) at its top, which tends to attach itself to the bottom of the continental crust. We examined whether or not the load due to mountain topography is balanced with the buoyancy load due to excess mass of the crust in the Andes. The Western Cordillera is found to be approximately in isostatic equilibrium, but the Eastern Cordillera is not. This contrast in mechanical state and the difference in recent geology suggest that the Western Cordillera and the Eastern Cordillera have not uplifted through entirely the same tectonic process.

Anionic polymerizations of 2-(4-vinylphenyl)ethoxy(trialkyl)silanes and 2-(4-vinylphenyl)ethoxy(t-butoxydimethyl)silane were investigated with oligo(α-methylstyryl)dilithium or -dipotassium as initiator in tetrahydrofuran at −78°C. These monomers readily polymerized to form ‘living polymers’. Subsequent deprotection of the silyl groups from the resulting polymers gave poly[2-(4-vinylphenyl)ethanol]s of the desired molecular weights with narrow molecular weight distributions ( M w M n = 1.05–1.21 ). The living polymers of the silyl ethers of 2-(4-vinylphenyl)ethanol can initiate further polymerization of either styrene or α-methylstyrene, yielding new block copolymers containing 2-(vinylphenyl)ethanol blocks.

A maximum entropy method (MEM) spectral analysis is made of the number of historically recorded meteorite falls in China from AD 619 to 1943 and the number of witnessed falls in the world during the period from 1800 to 1974. The presence of a 60 year period as suggested by previous workers, CHANG and YU (Mem. Natl Inst. Polar Res., Spec. Issue, 20,276,1981), is confirmed as a common feature of meteorite fall rate. In this paper the period is determined to be between 60 and 63 years. A periodicity of 240 years, also previously noted, is unstable in spectral analysis, suggesting that this periodicity may not exist. The presence of two more periodic components : ∿10.6 years and ∿17.7 years in meteorite flux is indicated from the power spectrum.

An extensive gravity survey was carried out from 1978 through 1980 in the area of the Central Ranges (Japan Alps), Honshu, which consist of the three largest mountain ranges in Japan (Hida, Akaishi, and Kiso). The Central Ranges area of 40, 000km2 has provided about 3, 700 gravity data including 2, 214 newly measured data, from which a Bouguer anomaly map was drawn. Bouguer and terrain corrections were made with a topographic data file of 230×280m2 grid at a distance of up to 80km from any measuring point, taking the earth's sphericity into account. A value of 2.64g/cm3 was used for the average density of surface features, and this was derived from the observed gravity data using a newly proposed least-squares method. The possible errors involved in the analysis were critically evaluated. The newly drawn anomaly map has an overall accuracy of 5mgal (=5×10-5m·sec-2). The Central Ranges area is known as a broad zone of strong negative anomaly, which has now been resolved into two parts, one along the axis of the Hida mountain range and the other along the northern Fossa Magna. Bouguer anomaly and topography are correlated negatively in the Hida range, marginally in the Akaishi range and positively in the Kiso range, suggesting that the correlation becomes progressively negative with increasing massiveness of mountain structure. The Central Ranges are bounded by the Itoigawa-Shizuoka Tectonic Line to the east and by the Atera fault to the southwest across which the regional Bouguer anomaly pattern changes sharply. The Atera fault is a firstclass active fault along which a narrow but very clear Bouguer low is observed that may be attributable to fault gouge material.

The extracts having diverse immunostimulating activities were obtained as a water-phase fraction from four bacterial species representing the 4 genera (Mycobacterium, Nocardia, Gordona, and Rhodococcus) of Mycobacteriaceae by the phenol-water method, which is commonly used for extraction of endotoxic lipopolysaccharides (LPS) from gram-negative bacteria and amphipathic substances from gram-positives. These fractions, especially those of G. aurantiaca and R. terrae, showed strong stimulatory effects on murine splenocytes, macrophages of mice and guinea pigs, the immunoadjuvant activities in guinea pigs and mice, and the distinct activities inducing a tumor necrosis factor and interferons alpha/beta and gamma in primed mice. The fractions from G. aurantiaca and R. terrae exhibited potent pyrogenicity and the ability to activate the clotting enzyme cascade of the horseshoe crab (Tachypleus tridentatus). Some of these biological activities were not very different from the potency of the reference endotoxic LPS derived from Escherichia coli or Fusobacterium nucleatum. But the test fractions neither showed the activity to prepare rabbit skin to the local Shwartzman reaction, nor reacted with anti-lipid A conventional and monoclonal antibodies. Furthermore, unlike LPS, these fractions stimulated the splenocytes of C3H/HeJ mice (LPS-Nonresponder). Although the fractions showing the above biological activities have not yet been adequately purified, they contained polysaccharides, whose main constituent sugar is mannose with a smaller amount of arabinose, fatty acids consisting primarily of palmitic, stearic, and tuberculostearic acids, and small amounts of peptides and amino sugars. Since components characteristic of known immunomodulators of bacterial origin, namely endotoxins (lipid A's), cell wall peptidoglycans, lipoteichoic acids, cord factors (trehalose dimycolates), or deoxyribonucleic acids, were practically not detected in these fractions, the agent responsible for the above bioactivities is considered to be a novel substance different from the known, bacterial immunomodulators.

Further comments on the analysis of dilute solution data are provided. Light-scattering and intrinsic-viscosity data used for this purpose are those obtained for monodisperse polystyrenes, prepared anionically in tetrahydrofuran, in benzene, toluene, and dichloroethane at 30°C and in cyclohexane at temperatures ranging from 32.2 to 60.1°C. The value of [η]θ/M1/2 is somewhat greater than the corresponding value for Berry’s polystyrenes prepared anionically in benzene, where [η]θ is the intrinsic viscosity at the theta temperature and M is the polymer molecular weight. This suggests that the two types of samples differ in microstructure, though the precise difference is unknown. However, it is shown that the two-parameter relationships established experimentally in the previous papers are well reproduced in the present data. The relationships are different from those determined by Kato, et al., for monodisperse poly(α-methylstyrene) prepared anionically. Since there is shown to be no essential difference between our and their methods of determining mean-square radii, it seems unlikely that the difference is related to measurements and subsequent treatments. It is suggested rather that the problem is related to Kato’s samples.

Snake bites are life-threatening injuries that can require intensive care. The diagnosis and treatment of venomous snake bites is sometimes difficult for clinicians because sufficient information has not been provided in clinical practice. Here we review the literature to present the proper management of bites by mamushi, habu, and yamakagashi snakes, which widely inhabit Japan and other Asian countries. No definite diagnostic markers or kits are available for clinical practice; therefore, definitive diagnosis of snake-venom poisoning requires positive identification of the snake and observation of the clinical manifestations of envenomation. Mamushi (Gloydius blomhoffii) bites cause swelling and pain that spreads gradually from the bite site. The platelet count gradually decreases due to the platelet aggregation activity of the venom and can decrease to100,000/mm(3). If the venom gets directly injected into the blood vessel, the platelet count rapidly decreases to10,000/mm(3) within 1 h after the bite. Habu (Protobothrops flavoviridis) bites result in swelling within 30 min. Severe cases manifest not only local signs but also general symptoms such as vomiting, cyanosis, loss of consciousness, and hypotension. Yamakagashi (Rhabdophis tigrinus) bites induce life-threatening hemorrhagic symptoms and severe disseminated intravascular coagulation with a fibrinolytic phenotype, resulting in hypofibrinogenemia and increased levels of fibrinogen degradation products. Previously recommended first-aid measures such as tourniquets, incision, and suction are strongly discouraged. Once airway, breathing, and circulation have been established, a rapid, detailed history should be obtained. If a snake bite is suspected, hospital admission should be considered for further follow-up. All venomous snake bites can be effectively treated with antivenom. Side effects of antivenom should be prevented by sufficient preparation. Approved antivenoms for mamushi and habu are available. Yamakagashi antivenom is used as an off-label drug in Japan, requiring clinicians to join a clinical research group for its use in clinical practice.

As a response to the recent article by Hifumi et al. published in the Journal of Intensive Care, the present correspondence clarifies the family-level taxonomy of the yamakagashi (Rhabdophis tigrinus). Further, the relevance of the term ‘venom-induced consumptive coagulopathy,’ instead of disseminated intravascular coagulation, in describing the procoagulant coagulopathy of R. tigrinus is highlighted.

Background Corynebacterium ulcerans is a pathogen causing diphtheria-like illness to humans. In contrast to diphtheria by Corynebacterium diphtheriae circulating mostly among humans, C. ulcerans infection is zoonotic. The present study aimed to clarify how a zoonotic pathogen C. ulcerans circulates among wild birds and animals. Results By screening 380 birds, a single strain of toxigenic C. ulcerans was isolated from a carnivorous bird, ural owl (Strix uralensis). The bacterium was also isolated from two individuals of Japanese shrew-mole (Urotrichus talpoides), a food preference of the owl. Analysis by ribotyping showed that the owl and mole isolates were classified in a group, suggesting that C. ulcerans can be transmissible among wild birds and their prey animals. Moreover, our isolates were found to belong to a group of previously reported C. ulcerans isolates from dogs and a cat, which are known to serve as sources for human infection. Conclusion The findings suggest that the shrew-mole may be a potential reservoir of a zoonotic pathogen C. ulcerans.

A new and powerful method of spectral analysis, which is named the “Sompi” method after a Japanese word, is introduced and applied to low-frequency seismograms. The Sompi method is based on an autoregressive (AR) process model, which is different from an ordinary prediction type AR model. In the ordinary AR model the AR coefficients predict the present observation from the past observations so that they are determined by minimizing the prediction error. The model implicitly assumes that the past observations are noise-free and that only the present observation consists of signal and noise. The method thus gives an unbiased estimate of the linear relationship among the past data and the present signal. In our AR model the AR coefficients extract signals from the time series so that they are determined by minimizing the extraction residual. The model assumes that each observation, either past or present, consists of signal and noise. The method thus gives an unbiased estimate of the linear relationship among the successive signals. Those who wish to make an unbiased spectral estimation for the signal must therefore minimize the extraction residual, rather than the prediction error. Minimization of the extraction residual leads to an eigenvalue problem of a non-Toeplitz matrix of autocovariance. The minimum eigenvalue yields the extraction residual which is an estimate of the noise power. The corresponding eigenvector constitutes the AR coefficients whose characteristic equation gives the complex frequencies (frequencies and decay or growth rates) of the signals extracted. The complex amplitudes (amplitudes and phases) are then determined through a least squares procedure. The Sompi method thus first retrieves medium-sensitive parameters, frequencies, and Q and then excitation-sensitive parameters, amplitudes, and phases. From the practical point of view it is not feasible to apply the Sompi method directly to such data as the Earth's free oscillations in which spectral peaks are densely and nonuniformly distributed over the entire frequency domain. We propose an algorithm of aliased sampling which enables us to apply the Sompi method to such data. In this algorithm the time series is first narrowly and sharply band-pass filtered. The resultant time series is then decimated at a rate corresponding to the bandwidth of the filter. The contributions of all the decimated time series, which may mutually lag in time, are stacked into the matrix elements of autocovariance for the eigenvalue problem. The Sompi method with this algorithm is tested against a synthetic seismogram to see the resolvability of the two modes closely spaced in frequency. The Sompi method is next applied to the seismograms of the 1977 Sumbawa Island earthquake recorded in the International Deployment of Accelerometers network. First, the two radial modes 0S0 and 1S0 are analyzed to examine the uniformity of their spectral parameters among different stations. Second, the fundamental multiplets 0Sl (l = 5–43) are analyzed to see how their initial amplitudes and phases oscillate with respect to l at one station. Third, the gravest mode 0S2 is analyzed in an attempt to resolve the five singlets with their Q values. Fourth, the analysis is made for the coupled multiplets 0Sl-0Tl+1 (l = 10–12) to observe their mutual repulsion in frequency and their mutual attraction in decay rate. Fifth, the core mode 7S3, a mode with most of its energy confined to the inner core, is detected. All five experiments demonstrate remarkable accuracy and resolvability of the Sompi method.

The locomotor behavior of Drosophila melanogaster was quantified in a large population of inbred lines derived from a single natural population, showing that many pleiotropic genes show correlated transcriptional responses to multiple behaviors., Background Locomotion is an integral component of most animal behaviors, and many human health problems are associated with locomotor deficits. Locomotor behavior is a complex trait, with population variation attributable to many interacting loci with small effects that are sensitive to environmental conditions. However, the genetic basis of this complex behavior is largely uncharacterized. Results We quantified locomotor behavior of Drosophila melanogaster in a large population of inbred lines derived from a single natural population, and derived replicated selection lines with different levels of locomotion. Estimates of broad-sense and narrow-sense heritabilities were 0.52 and 0.16, respectively, indicating substantial non-additive genetic variance for locomotor behavior. We used whole genome expression analysis to identify 1,790 probe sets with different expression levels between the selection lines when pooled across replicates, at a false discovery rate of 0.001. The transcriptional responses to selection for locomotor, aggressive and mating behavior from the same base population were highly overlapping, but the magnitude of the expression differences between selection lines for increased and decreased levels of behavior was uncorrelated. We assessed the locomotor behavior of ten mutations in candidate genes with altered transcript abundance between selection lines, and identified seven novel genes affecting this trait. Conclusion Expression profiling of genetically divergent lines is an effective strategy for identifying genes affecting complex behaviors, and reveals that a large number of pleiotropic genes exhibit correlated transcriptional responses to multiple behaviors.