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We report on the operation of co-located ${}^{129}$Xe and ${}^{131}$Xe nuclear spin masers with an external feedback scheme, and discuss the use of ${}^{131}$Xe as a comagnetometer in measurements of the ${}^{129}$Xe spin precession frequency. By applying a correction based on the observed change in the ${}^{131}$Xe frequency, the frequency instability due to magnetic field and cell temperature drifts are eliminated by two orders of magnitude. The frequency precision of 6.2 $\mu$Hz is obtained for a 10$^4$ s averaging time, suggesting the possibility of future improvement to $\approx$ 1 nHz by improving the signal-to-noise ratio of the observation., Comment: 8 pages, 5 figures

In this chapter, we discuss the mechanism of self-propulsion using simple theoretical models. Particular focus is placed on the roles of hydrodynamic flow on self-propelled particles and drops. We also theoretically investigate self-propelled motion of chemically driven drops. The motion is driven by hydrodynamic flow resulting from the Marangoni effect and occurs for drops under an isotropic chemical reaction rather than under an anisotropic temperature and/or concentration gradient. This occurs even under the low Reynolds number in which fluid flow is described by the linear equations. We propose the mechanism of spontaneous symmetry breaking where hydrodynamics plays a significant role when coupled with nonlinear effects. We summarize the basic theoretical aspects of this phenomena including the reaction-diffusion equations and the hydrodynamic equation. We also discuss the collective behaviours of the drops by analysing the interaction between the self-propelled drops.

This paper describes a turnout without movable parts for magnetically levitated vehicles with hybrid magnets, which have been studied by the authors in place of street cars. Their low construction cost and low maintenance are key to their practical use. Magnetic levitation systems using forces of attraction can generate guidance force automatically, but the damping force against lateral motion is negligible. However, the lateral damping characteristic was improved by using divided iron type magnets and rails. Using this turnout without movable parts will facilitate smooth direction switching.

Generator coordinate method (GCM) combined with particle number and triaxial angular momentum (spin) projections is applied to single j-shell model with the monopole-pairing interaction (MPI) and the quadrupole-quadrupole interaction (QQI). The GCM calculation yields excellent results, e.g. the GCM with the QQI reproduces exact energy spectra of all the excited states for 4-hole (also particle) systems in the j = 112 152 and 192 shells; and the GCM with the MPI plus QQI, which requires simultaneously the particle number projection, reproduces exact energy spectra for the 6-hole (also particle) systems except for the spin I = 1 state in the j = 132 shell. it turns out that components of triaxial deformation contribute much to reproduce correct physical states, so that the triaxial spin projection is essential in the present GCM.

The quon algebra, which interpolates between the Bose and Fermi algebras and depends on a free paramenter q, is used to generate a deformed Dyson boson expansion of the quadrupole operator. Then we obtain a quadrupole-quadrupole hamiltonian, for a single j-shell, in terms of this deformed bosonic operator. The hamiltonian is diagonalized and its eigenvalues are compared with the ones obtained from the fermionic quadrupole-quadrupole hamiltonian. The deformation parameter helps in achieving the correct excitation energy levels, what cannot be encountered in practice with the usual non-deformed Dyson expansion.

The formation of the cold-rolling and annealing texture has been investigated in electrolytically deposited pure iron having a sharply developed //ND fiber texture without any anisotropy along γ-fiber nor any orientation density along other fibers. In no respect of cold reduction, {111} texture is formed after cold-rolling. The same texture still remains after the recrystallization in the 65% cold-rolled sheet, whereas the position of the peak is shifted from {111} towards {111} through recrystallization in the 80% cold-rolled sheet. The nucleation texture seems to be responsible for the difference of recrystallization texture between the 65 and 80% cold-rolled sheets. Additionally, it is thought that the growth of the recrystallized grains also plays an important role. It is considered that the recrystallized nuclei with {111} orientation can hardly grow into the deformed matrix of the 80% cold-rolled sheet because they frequently encounter the deformed grains with nearly the same orientation and thus suffer from a reduced mobility. On the other hand, nuclei with a {111} orientation can easily grow into the deformed {111} grains because of the favorable growth orientation relationship between those. Conversely, in 65% cold-rolled sheet, the nuclei with {111} are considered to grow more easily since the frequency of pinning due to limited mobility of a low angle grain boundary is rather small, as compared to that of the 80% cold-rolled sheet. The same mobility argument as applied to the growth of nuclei seems to hold also for the growth of subgrains, namely, nucleation texture formation.

Accurate prediction of contact behaviour between machine tools and metals is required for the mechanical design of machinery. In this article, the numerical analysis of the contact behaviour is described by incorporating the subloading-overstress model [6] which is capable of describing the contact behaviour for a wide range of sliding velocity including the increase of coefficient of friction with the increase of sliding velocity. And its validity is verified by the comparison with some test results. First, in order to examine the influence of sliding velocities on the friction properties, the flat-surface friction tests for lubricated interfaces between galvannealed steel sheet and SKD-11 tool steel were performed. As a result, It is observed that the friction smoothly translate to kinetic friction, after exhibiting the peak at the static friction. In addition, it is observed that the higher the sliding velocity, the larger the friction resistance, meaning the positive rate sensitivity. Then the subloading-overstress model is implemented in the finite element analysis program ABAQUS/Standard, and it is used to simulate the flat-surface friction tests. The predictions from the finite element analysis are shown to be in very good agreement with experimental results.

Maize seedlings emit sesquiterpenes during the day in response to insect herbivory. Parasitoids and predators use induced volatile blends to find their hosts or prey. To investigate the diurnal regulation of biosynthesis and emission of induced sesquiterpenes, we applied linolenoyl-L-glutamine (LG) to maize seedlings in the morning or evening using a cut-stem assay and tracked farnesene emission, in planta accumulation, as well as transcript levels of farnesyl pyrophosphate synthase 3 (ZmFPPS3) and terpene synthase10 (ZmTPS10) throughout the following day. Independent of time of day of LG treatment, maximum transcript levels of ZmFPPS3 and ZmTPS10 occurred within 3-4 h after elicitor application. The similarity between the patterns of farnesene emission and in planta accumulation in light-exposed seedlings in both time courses suggested unobstructed emission in the light. After evening induction, farnesene biosynthesis increased dramatically during early morning hours. Contrary to light-exposed seedlings dark-kept seedlings retained the majority of the synthesized farnesene. Two treatments to reduce stomatal aperture, dark exposure at midday, and abscisic acid treatment before daybreak, resulted in significantly reduced amounts of emitted and significantly increased amounts of in planta accumulating farnesene. Our results suggest that stomata not only play an important role in gas exchange for primary metabolism but also for indirect plant defences.

This paper reports the experimental results of the load variation characteristics of a magnetically levitated vehicle with hybrid magnets, which we studied in place of street cars and conveyor systems. Magnetically levitated systems have the following advantages: no bearings, no wheels, no noise, no air pollution and low maintenance. We propose new constructive electromagnets and magnetic rails. The magnetically levitated part must be cordless and the power source has involve Ni-MH AA size rechargeable batteries. As a experimental result, the number of dry cell batteries is increased with increasing load.

The structure of doublet bands associated with neutron 0h11/2 and proton 0g9/2 orbital in the doubly‐odd nuclei, 98–104Tc and 100–106Rh is studied theoretically using the quadrupole coupling model. The calculated energy levels and electromagnetic transitions are in excellent agreement with experimental data. The internal structure of the yrast states is discussed in terms of the QCM wave functions.

Nuclear structure of the neutron‐rich Se, and Ge isotopes is theoretically studied in terms of the spherical full shell model with the monopole and quadrupole pairing plus quadrupole‐quadrupole interaction. The experimental energy levels of low‐lying states as well as high‐spin states are well reproduced. The shell model results are examined in details in a pair‐truncated shell model. The analysis shows the alignment of two g9/2 neutrons at high spins.

The pair subspaces, the SD and SDG subspaces, are constructed for non-degenerate orbits. Eigenstates for the effective interactions in these subspaces are calculated and compared to the shell-model results in vibrational and deformed regions. The fermion interactions are mapped onto the corresponding boson ones using the mapping procedure by Otsuka, Arima and Iachello (OAI).

Electro-deposited pure Fe has a characteristic of having very sharp isotropic ND// fiber texture with a needle-like shaped fine grain elongated to ND. This Fe exhibits a surprisingly high r-value of over 7; however, such a high r-value might not be rationalized only from texture. Careful slip analyses reveal that restricted slips take place in the specific {110} slip planes, which are perpendicular to the sheet surface. Since grain boundaries with columnar structure are also perpendicular to the sheet surface, the slip plane in a certain grain may easily connect to the slip plane in adjacent grains having within ±30 degree rotation relationship around the common axis of ND// . The operation of such a slip system is considered to cause the width strain much larger than the thickness strain. Furthermore, the texture evolution during cold-rolling and subsequent annealing was investigated using electro-deposited pure Fe as a starting material. Regardless of the amount of cold-rolling reduction, 65% to 90%, {111} cold-rolling texture developed. After recrystallization, {111} texture remained when material is cold-rolled by 65%, while {111} texture developed when materials are cold-rolled by 80% and 90%. From the investigation into the mechanism on the development of recrystallization texture, the oriented nucleation and selective growth theories are concluded to contribute to the evolution of annealing texture.

We propose a new formula to evaluate the ground state energy of the two‐body random Hamiltonian in terms of the average energy and the width of eigen‐energies. For fermions in a single orbital, we obtain an excellent agreement between the spin I ground state probabilities predicted by using our formula and those obtained by diagonalizing the random Hamiltonian.

Nuclei around mass 130 have many interesting features such as high-spin isomers, backbending phenomena, even-odd energy staggering of quasi-γ band caused by a soft triaxial deformation, and features recently referred to as “chiral bands”. Moreover, the beta-decays and electron-captures in this region provide us with necessary information for predicting the abundance of nuclei in the environment of super-nova explosions. The nuclei in this region are neither vibrational nor rotational. Thus it is very difficult to treat themin terms of conventional mean field theories. To overcome this difficulty, we construct many-body states in terms of collective nucleon pairs which have angular momenta zero (S) and two (D). The purpose of this paper is to understand many seemingly different features in this region in a self-consistent and unified way. In order to understand systematics, we introduce effective interactions which depend smoothly on the neutron and proton numbers. It is found that energy spectra of the yrast and quasi-⋎-bands of Xe, Ba and Ce isotopes are nicely reproduced along with inter- and intra-band E2 transitions, which simulate the typical features of the O(6) limit of the interacting boson model.

A multinucleon transfer reaction between a thin self-supporting Pt-198(78) target and an 850 MeV Xe-136(54) beam has been used to populate and study the structure of the N=80 isotone Ba-136(56). Making use of time-correlated gamma-ray spectroscopy, evidence for an I-pi=(10(+)) isomeric state has been found with a measured half-life of 91+/-2 ns. Prompt-delayed correlations have also enabled the tentative, measurement of the near-yrast states which lie above the isomer. Shell-model calculations suggest that the isomer has a structure which can be assigned predominantly as (nuh(11/2))(10+)(-2). The results are discussed in terms of standard and pair-truncated shell-model calculations, and compared to the even-Z N=80 isotones ranging from Sn-130(50) to Er-148(68). A qualitative explanation of the observed dramatic decrease in the B(E2:10(+)-->8(+)) value for the N=80 isotones at Ba-136 is given in terms of the increasing single-hole energy of the h(11/2) neutron configuration as the proton subshell is filled. The angular momentum transfer to the binary fragments in the reaction has also been investigated in terms of the average total gamma-ray fold versus the scattering angle of the recoils.

In this paper, we report our systematic calculations of angular momentum I ground state probabilities $P(I)$ of boson systems with spin l in the presence of random two-body interactions. It is found that the $P(0)$ dominance is usually not true for a system with an odd number of bosons, while it is valid for an even number of bosons, which indicates that the $P(0)$ dominance is partly connected to the even number of identical particles. It is also noticed that the ${P(I}_{\mathrm{max}})$'s of bosons with spin l do not follow the $1/N$ $(N=l+1,$ referring to the number of independent two-body matrix elements) relation. The properties of the $P(I)$'s obtained in boson systems with spin l are discussed.

The ground states of all even-even nuclei have angular momentum, $I$, equal to zero, I=0, and positive parity, $\pi=+$. This feature was believed to be a consequence of the attractive short-range interaction between nucleons. However, in the presence of two-body random interactions, the predominance of $I^{\pi}=0^+$ ground states (0 g.s.) was found to be robust both for bosons and for an even number of fermions. For simple systems, such as $d$ bosons, $sp$ bosons, $sd$ bosons, and a few fermions in single-$j$ shells for small $j$, there are a few approaches to predict and/or explain spin $I$ ground state ($I$ g.s.) probabilities. An empirical approach to predict $I$ g.s. probabilities is available for general cases, such as fermions in a single-$j$ ($j>7/2$) or many-$j$ shells and various boson systems, but a more fundamental understanding of the robustness of 0 g.s. dominance is still out of reach. Further interesting results are also reviewed concerning other robust phenomena of many-body systems in the presence of random two-body interactions, such as the odd-even staggering of binding energies, generic collectivity, the behavior of average energies, correlations, and regularities of many-body systems interacting by a displaced two-body random ensemble., Comment: finalized version, review article (103 pages, 23 figures). accepted by Physics Reports

The validity of the quantum-number-projected generator coordinate method (PGCM) is investigated within the proton-neutron single-j shell model. The results of the PGCM are compared with exact solutions in the shell model. It is concluded that the PGCM provides a good approximation of the shell model for low-lying collective states. In order to describe the proton-neutron relative motion such as a scissors mode, we also propose a truncation scheme in terms of the PGCM. Various classes of PGCM truncations are examined by changing sets of generator coordinates. Flexibility with respect to the choice of generator coordinates is advantageous to illuminate the underlying physics. As an application of the PGCM truncation, the $M1/E2$ transition probabilities concerning the ${I=1}^{+}$ scissors state are analyzed for nuclei exhibiting stable triaxiality. The electromagnetic properties are identified. Those are characteristic of the $O(6)$ dynamical symmetry limit of the proton-neutron interacting boson model.

Xe isotopes near mass $A\ensuremath{\sim}130$ region, which exhibit features of O(6) symmetry at low energy and the backbending at high spins, are studied in the shell model framework. The monopole and quadrupole pairing plus quadrupole-quadrupole interaction is employed as an effective interaction. As for single-particle levels, the ${1d}_{3/2},$ ${0h}_{11/2},$ ${2s}_{1/2}$ orbitals are taken into account for neutrons and the ${1d}_{5/2},$ ${0g}_{7/2}$ orbitals for protons under the assumption of $N=Z=64$ subshell closure. The calculation reproduces the experimental energy levels of high-spin states as well as low-lying states well. This is the first successful microscopic description of the backbending in this mass region. The shell model states are examined in pair-truncated models. The analysis shows the alignment of two ${0h}_{11/2}$ neutrons at high spins.

Rapid response to IFN-α in a patient with relapsed follicular lymphoma after cord blood transplantation

A 44-year-old man with CML in chronic phase was admitted for BMT from an HLA-identical sibling. Ph positive cells were undetectable at 3 and 7 months after BMT but became detectable by cytogenetic analysis of bone marrow aspirates at 12 months after BMT. He was treated with IFN-alpha (6 million units/day, 3 times a week) without apparent effect. Donor leukocyte transfusion (DLT) was performed four times between 20 months and 23 months after BMT, transfusing 3.4 x 10(8) mononuclear cells/kg. However, leukocytosis appeared and the NAP score declined at 25 months after BMT. FISH analysis revealed an increase in bcr-abl positive cells. IFN-alpha was restarted using the same schedule at 26 months after BMT. Three months after restarting IFN-alpha, the leukocyte count fell to the normal range, NAP score increased to a normal level, and bcr-abl positive cells decreased markedly. He has remained in hematological and cytogenetic remission for 20 months, and bcr-abl chimeric mRNA remained undetectable by PCR. These results suggest that CML which does not respond to DLT may be cured by subsequent IFN-alpha therapy, possibly by inducing anti-leukemia immune responses.

We retrospectively reviewed clinical and hematologic features of nine patients with acquired idiopathic sideroblastic anemia (AISA). Seven of them had ringed sideroblasts (RS) more than 15% of marrow nucleated cells. RS persisted in the marrow even in the remaining two patients who had a relatively low marrow erythroblasts despite RS ranging from 1/4 to half of the marrow erythroid series. However, RS declined in proportion in another two patients of the nine whose disease progressed to refractory anemia with excess of blasts (RAEB), although a high proportion of RS reappeared in one patient at the time of relapse following allogeneic marrow transplantation. A similar decline of RS concomitant with disease progression was also seen in seven additional patients with RAEB or RAEB in transformation (RAEB-t) with sideroblastic erythropoiesis. Cytogenetic abnormalities, although rare initially, became detectable either at the time of disease progression or at the worsening of anemia in AISA. These observations suggest that the majority of AISA fall in the category of myelodysplasia, and that a progressive decline in RS is part of the natural history of myelodysplasia. Closer follow-up of the proportion of RS in patients with AISA is warranted to better understand its biologic significance.

Nuclear structure of the doublet bands in the doubly-odd nuclei with mass A ~ 130 is studied in terms of a pair-truncated shell model. The model reproduces quite well the energy levels of the doublet bands and the electromagnetic transitions. The doublet bands turn out to be realized by the chopsticks-like motion of two angular momenta of the unpaired neutron and the unpaired proton, weakly coupled with the quadrupole collective excitations of the even-even part of the nucleus.

The negative-parity states in 132Ba are studied in terms of the pair-truncated shell model. The model reproduces experimental energy levels of the ΔI = 1 band with the ν(h211/2)⊗π(h11/2g7/2) configuration. From analysis of its structure, it is found that two angular momentum vectors representing valence neutrons and protons gradually close as total spin increases.

A microscopic interacting boson model calculation is performed for Ba isotopes. The boson interactions are constructed by applying the Otsuka–Arima–Iachello mapping procedure to the phenomenological interactions given in previous systematic studies for A ~ 130 nuclei. The theoretical energy levels in the IBM are found to be in good agreement with those of the pair-truncated shell model.

Alpha interferon is an immune modulator used in the treatment of hematologic malignancies and immunosuppressive diseases. While many of the clinical indications for interferon have been well described and are FDA-approved, a large number of clinical uses of interferon are being developed. This study evaluated the appropriateness, efficacy, and safety of interferon therapy at our institution from 1987 to 1991. Data were collected by chart review. Response rates of patients in this hospital were compared to those published in the literature. Twenty-six patients were prescribed alpha interferon. Ten patients (38%) demonstrated a partial response, the highest responses seen in Hairy cell leukemia (67%) and chronic myelogenous leukemia (57%). Response rates for each disease compared favorably to those predicted from the literature. Twelve patients (46%) demonstrated intolerance. Overall five patients (19%) remain on therapy. While interferon appears to be moderately effective in certain diseases, intolerance to interferon seems to be the major limiting factor to its clinical application.

A 57-year-old man was admitted because of fever and night sweat. The bone marrow was hypercellular with 86.4% blast cells. The diagnosis of AML (M0) was made, because the blast cells were negative for peroxidase stain and had CD13 and no lymphoid antigens in marker analysis. The patient was treated with BH-AC.TMP, BH-AC.MVP and low dose Ara-C without any hematological improvement, and even additional treatment with medium dose Ara-C resulted in 66.4% blast cells in the bone marrow. Subsequent administration of rhG-CSF (150 micrograms/day) by continuous intravenous infusion resulted in the decrease of the blast cells in the bone marrow to a level that was evaluated as complete remission. He remains in complete hematological remission at present. As shown in this case, rhG-CSF might be an effective agent for the treatment of AML, even if the mechanism of its effectiveness is unclear at present. Further clinical studies should will supply useful information to analyze the pathophysiology of AML.

We analyze the quantum level statistics of the zero-obstacle-size limit of the pseudointegrable billiard While the nearest-neighbor-spacing distribution approaches to the Poissonian shape in the semiclassical limit, it is shown to become the Wigner distribution in low-energy region. This fact is interpreted as a signature of the chaotic motion generated by the quantum uncertainty.

The sdg interacting boson hamiltonian is derived in the seniority scheme. We use the method of Otsuka, Arima and Iachello in order to derive the boson hamiltonian from the fermion hamiltonian. To examine how good is the boson approximation in the zeroth-order, we carry out the exact shell model calculations in a single j -shell. It is found that almost all low-lying levels are reproduced quite well by diagonalizing the sdg interacting boson hamiltonian in the vibrational case. In the deformed case the introduction of g-bosons improves the reproduction of the spectra and of the binding energies which are obtained by diagonalizing the exact shell model hamiltonian. In particular the sdg interacting boson model reproduces well-developed rotational bands.

The pair subspaces — the SD- and SDG-subspaces — are constructed. Eigenstates for a quadrupole force and transition rates for a quadrupole operator are calculated in the single j -shell-model. The SDG-pair approximation is found to be excellent in describing the low-spin states of the ground bands compared to exact shell-model calculations. The fermion interactions are mapped onto the corresponding boson ones using the mapping procedure by Otsuka, Arima and Iachello (OAI). The OAI approximation in zeroth-order fails in reproducing the ground-state energies in the deformed limit.

The sdg interacting-boson model is presented in the SU(3) tensor formalism. The interactions are decomposed according to their SU(3) tensor character. The existence of the SU(3)-seniority preserving operator is found to be important. The model is applied to $^{168}\mathrm{Er}$. Energy levels and electromagnetic transitions are calculated. This model is shown to solve the problem of anharmonicity regarding the excitation energy of the first ${K}^{\ensuremath{\pi}}$${=4}^{+}$ band relative to that of the first ${K}^{\ensuremath{\pi}}$${=2}^{+}$ one. E4 transitions are calculated to give different predictions from those by the quasiparticle-phonon nuclear model.

We give the intrinsic states explicitly in the boson representation in the framework of the sdg interacting boson model. Although they are only valid in the large-N limit, they are useful to estimate various physical quantities in well deformed nuclei. One can compare these results with those predicted in the IBM1 or in the IBM2.

Fibrous particles 20—50A wide and several μm long have been found in the clay fractions from a number of Japanese and Scottish soils. The particles dissolved in buffered dithionite and hot acid oxalate (0.15 M ) but were resistant to hot alkali (2% Na 2 CO 3 , 0.5 M NaOH) and acid (0.1 M HCl) treatments, suggesting a ferruginous and crystalline nature. The ferruginous nature was further indicated by energy-dispersive X-ray spectroscopy, which, at the same time, showed the presence of large quantities of Al and some Si. Electron diffraction analysis indicated goethite of low crystallinity as the most likely mineral. Incorporation of numbers of Al ions in the crystal lattice was inferred from the results of elemental analysis after chemical dissolution treatments.